JP4532844B2 - SURFACE IDENTIFICATION DEVICE, HEATING DEVICE USING THE SAME, AND IMAGE FORMING DEVICE - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a surface property identification device for identifying a difference in surface frictional resistance of a measured object, a difference in surface roughness and a surface material as a cause thereof, and a heating device and an electrophotographic printer equipped with this device The present invention relates to an image forming apparatus such as a copying machine, an ink jet printer, a thermal head printer, a dot impact printer, a facsimile, or a composite device thereof.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, various image forming apparatuses are apparatuses for forming an image on a sheet-like recording material such as plain paper, postcard, cardboard, sealed letter, OHP plastic thin plate, etc. In apparatuses such as printers, copiers, and facsimile machines that use this method, a toner image is formed on a recording material by electrostatic image forming means using toner as a developer, and then the recording material is heated and heated by fixing means. The toner image is melted and fixed under pressure to form an image.
[0003]
In addition, other devices such as printers, copiers, and facsimiles using an ink jet system use ink as a developer and use a number of nozzles having minute orifices utilizing mechanical or thermal reactions. An image is formed on the recording material by image forming means for ejecting ink from the configured recording head at a high speed.
[0004]
In addition, other apparatuses such as printers, copiers, and facsimile machines using a thermal transfer method use an ink ribbon as a developer and use a thermal head to transfer ink from the ink ribbon to the recording material by means of image forming means. An image is formed.
[0005]
By the way, these devices have been improved in recent years, and devices for higher image quality and higher processing speed have been realized by various means. At the same time, cost reduction measures have been devised to reduce costs. Advancing and becoming widespread.
[0006]
However, the types of recording materials used in these image forming apparatuses vary widely, from plain paper to high-grade paper with special surface treatment for sealed letters and resin sheets for OHP. Accordingly, since it has been used all over the world, it is necessary to cope with it so that a good image can be formed on any recording material used in various places. The roughness of the recording material surface, which greatly affects the recording material, is a very important factor.
[0007]
For example, in an apparatus employing an electrophotographic system, when the surface of the recording material used is smooth (hereinafter referred to as smooth paper) or rough (hereinafter referred to as rough paper), the paper surface from the heating source in the fixing unit The heating efficiency for transferring heat to the surface differs according to the difference in thermal resistance due to the difference in surface properties, and even if the rough paper is fixed at an appropriate fixing temperature with smooth paper, it causes insufficient fixing. It is necessary to fix at a high temperature. For this reason, the current apparatus uses the temperature at which rough paper can be fixed as the standard fixing temperature, and is always fixed at an excessive temperature for smooth paper, and even for rougher paper. Since a higher fixing temperature is required, a selection mode is provided for allowing the user to change the setting of the fixing temperature when using such paper.
[0008]
FIG. 2 shows the basic configuration of a printer that employs an electrophotographic system as a specific example of these.
[0009]
That is, FIG. 2 is a cross-sectional view of a main part of a conventional printer. In this printer, the surface of the photosensitive drum 2 is uniformly charged to a predetermined polarity by the charging roller 1 and then exposed by an exposure means 3 such as a laser. Only the area where the photosensitive drum 2 is exposed is neutralized to form a latent image on the photosensitive drum 2. The latent image is developed by the toner 5 of the developing device 4 to be visualized as a toner image. That is, the toner 5 of the developing device 4 is frictionally charged with the same polarity as the charging surface of the photosensitive drum 2 between the developing blade 4a and the developing sleeve 4b, and DC and AC are developed in the developing gap portion where the photosensitive drum 2 and the developing sleeve 4b face each other. A bias is applied in a superimposed manner, and the toner 5 is selectively attached to the latent image forming portion of the photosensitive drum 2 while floating and oscillating by the action of an electric field, and then the toner 5 is transferred by the transfer roller 6 and the photosensitive drum 2. The photosensitive drum 2 is conveyed to the nip portion by rotation.
[0010]
On the other hand, a recording material 7 such as paper on which an image is recorded is fed from the recording material storage box 7a ′ to the vertical conveying roller pair 7d by the paper feeding roller pair 7c (the lower roller may be a pad). The pair of vertical transport rollers 7d is transported to either the pre-transfer transport roller 7d 'or the manual feed tray 7b is transported to the pre-transfer transport roller 7d' by the paper feed roller pair 7c. Further, the pre-transfer conveying roller 7d ′ is conveyed to the transfer nip portion at a predetermined approach angle between the upper transfer guide plate 9 and the lower transfer guide plate 9 ′. Until the recording material 7 is conveyed from the pre-transfer conveying roller 7d ′ to the transfer nip portion, the recording material 7 is rubbed with various members that are in contact before the recording material 7 is conveyed to this region. Since there is a possibility that the surface of the material 7 is charged, the back surface of the recording material 7 being transported by the neutralizing brush 8 for removing such unnecessary charging that causes an image disturbance when performing electrostatic recording is provided. It is provided in contact with the side and is grounded.
[0011]
In order to electrostatically attract the toner 5 on the photosensitive drum 2 and move it to the recording material 7 side in the transfer portion, a high voltage having a polarity opposite to that of the toner 5 is applied to the transfer roller 6 on the back surface of the recording material 7. The toner 5 is electrostatically attracted to the back surface of the toner and the toner image is transferred to the recording material 7, and the back surface of the recording material 7 is charged with a polarity opposite to that of the toner 5, so that the transferred toner 5 is continuously held. The transfer charge is applied to the back surface of the recording material 7.
[0012]
Finally, the recording material 7 onto which the toner image has been transferred is conveyed to a fixing device 12 composed of a heating rotator 13 and a pressure roller 14 that forms a nip portion, and a fixing temperature preset in the nip portion is set. The toner image is fixed by being heated and pressurized while being controlled by a heater provided on the heating rotator 13 side so as to be held.
[0013]
In addition, since the deposits such as toners having different polarities remain slightly on the surface of the photosensitive drum 2 after the toner image transfer, the surface of the photosensitive drum 2 after passing through the transfer nip portion is the surface of the photosensitive drum 2 by the cleaning container 10. After the adhering matter is scraped off and cleaned by the cleaning blade 10a that is in contact with the counter, the apparatus waits for the next image formation.
[0014]
The above-described components of the charging roller, the photosensitive drum, the developing container, and the cleaning container have a relatively short replacement cycle. Therefore, a cartridge replacement type apparatus that can be replaced in units of the cartridge 11 in which these components are integrated is widely used. is doing.
[0015]
Among the above processes, a contact heating type fixing device with good thermal efficiency and safety is widely known as an image fixing method. Conventionally, a release layer is mainly formed on the surface of a metal cylindrical metal core. Then, a heat fixing roller containing a halogen heater inside the cylinder and an elastic layer made of heat-resistant rubber formed on the metal core, and a pressure roller formed by forming a pressure-side release layer on the surface are pressed. In recent years, a heat roller fixing device constructed by abutting has been used. However, as a method with higher heating efficiency, a surface of a heat resistant resin film having a low heat capacity is processed into a cylindrical shape instead of the heat fixing roller. A film heating type fixing device is used in which a fixing film on which a release layer is formed is used and a ceramic heater is brought into contact with and heated from the inside of the fixing nip portion of the film.
[0016]
This type of film heating type fixing device has higher heat transfer efficiency than the conventional heat roller method using a cylindrical metal containing a halogen heater as a fixing roller from the viewpoint of promoting energy saving in recent years, and the apparatus is also started up. Although it has been attracting attention as a fast method and has been applied to higher-speed models, it is necessary to reduce the heat capacity of the heating surface of the fixing unit in order to emphasize the rate of temperature increase. It is difficult to form an elastic layer on the heating surface, and a hard heating surface is used. For this reason, this type of fixing method has a configuration in which a difference in heating efficiency is likely to occur due to unevenness on the surface of the recording material.
[0017]
In various image forming apparatuses such as a printer using such a fixing device, as the processing speed is increased as described above, there is a problem that a difference in fixing property becomes remarkable due to a difference in paper type. The user himself / herself needs to input an appropriate fixing mode to the printer in advance according to the type of paper that the user intends to use.
[0018]
However, forcing the user to select a mode in order to switch the fixing condition each time depending on the type of paper used in this way increases the work burden on the user, and if the selection mode is wrong, fixing the print amount. However, there is a possibility that power is wasted due to excessive heating, power is wasted, image defects occur due to high temperature offset, and toner contamination of the fixing device is caused.
[0019]
Further, in a usage environment in which a single network printer is shared by a plurality of users as in recent years, a special user uses a special paper and switches the mode setting accordingly, and then the special paper is used. May be left on the device, and when used by other users who do not know that, the modes may not match and may not be properly fixed, causing the problem described above. It is high.
[0020]
Also, regarding the number of fixing modes that can be set, there are strictly different levels of actual paper smoothness, and it is impossible to set optimum conditions for each of them. The number of setting modes is limited by batch-fixing papers with smoothness in a range in the same mode. For certain papers, fixing may be performed using more power than necessary. Depending on the combination, inefficient fixing may be performed.
[0021]
On the other hand, in the apparatus employing the ink jet method, the amount of ink required differs between the case where the recording material used is smooth paper and the case of rough paper, and an image on the rough paper with an appropriate amount of ink on smooth paper. Even if it is formed, the ink permeates in the thickness direction of the paper and causes a lack of density, so it is necessary to eject more ink to the rough paper. For this reason, in the current apparatus, it is necessary for the user to perform an operation for causing the printer to recognize the paper type in advance for the paper having different surface properties.
[0022]
Also, in the apparatus adopting the thermal transfer method, the amount of power required differs between the case where the recording material used is smooth paper and the case of rough paper. However, since the thermal resistance is large, the transferability of the ink is lowered and the density is insufficient.
[0023]
As described above, in all current apparatuses, excessive temperature, ink, and power are consumed to prevent image quality deterioration due to the surface roughness of the recording material, and image quality is deteriorated. In order to prevent this, it is necessary to switch these conditions according to the surface roughness of the recording material, but at present, complicated methods used in methods and some devices that force the user to change settings In addition, only optical sensors that require signal processing have been considered, leading to a significant increase in cost.
[0024]
For this reason, several proposals have been made so far for detecting the roughness of the surface of the recording material and changing the image forming conditions according to the detection result. Examples of the detection principle capable of detecting the recording material surface roughness include those disclosed in Japanese Patent Application Laid-Open Nos. 2000-314618 and 2000-356507. In these proposals, the contact means that contacts the surface of the recording material detects physical phenomena such as vibration and rubbing sound caused by rubbing against the surface of the recording material, and detects the difference in the detected amount as the difference in surface roughness. As a specific configuration thereof, a configuration is proposed in which a piezoelectric element is provided in the contact means and vibration is converted into an electrical signal and detected.
[0025]
However, the above proposal does not disclose in detail the specific configuration conditions necessary for a member (hereinafter referred to as a probe) that is actually brought into contact with the surface of the recording material, and a simple linear probe is located upstream in the transport direction. However, only one configuration is shown in which one end is fixed and the downstream end abuts against the oblique transport direction so as not to be opposed to the diagonal conveyance direction. It was difficult.
[0026]
For this reason, in order to dramatically improve the surface property discrimination performance and make it practical with a detection method using a piezoelectric element, the author newly studied the sensor probe shape and mounting configuration, and applied the tip to the probe tip. A structure that allows the contact portion to vibrate on the transport plane in the front and rear directions in the transport direction is provided, and the tip contact portion is set at an angle that bites into the measurement surface against the transport direction, resulting in extremely high discrimination performance. As a configuration that realizes such a structure at the lowest cost without impeding paper conveyance, a probe having an S-shaped side surface formed by bending a strip-shaped sheet metal twice is fixed to a rotating shaft for rotation. The S-shaped surface property detection sensor 15 having the above structure is devised, and as shown in the center of FIG. 2, this sensor can detect whether paper is fed from either a paper cassette or a manual feed tray. The As a result of evaluation by attaching to the optimum transfer upper guide 9 as a position that can be detected from the front side of the paper on the downstream side in the paper conveyance direction of the paper conveyance path of the person, it is very high without hindering the paper conveyance. It was confirmed that discrimination performance was obtained.
[0027]
More specifically, as shown in FIG. 3 (A), this sensor has an S-shaped probe 15a having a piezoelectric element portion 15b formed in a flat portion, and an end on the opposite side to a probe holder 15c with a fixing screw 15d. The probe holder 15c is fixed to a probe rotation shaft 15e having an axial direction perpendicular to the conveyance direction and parallel to the conveyance plane, and the probe tip is conveyed about the probe rotation axis 15e. It is pressed against the flat surface by a pressing means (not shown) with a contact pressure of about 10 to 30 g. Further, the probe rotating shaft 15e is fixed on the sensor holding plate 15g via a bearing 15f, and a transport flat plate 15h is provided on the paper transport path as a transport plane. FIG. 2 (C) shows the arrangement relationship of these members when these components are viewed from above. The tip of the S-shaped surface property detection sensor 15 is placed at the center of the sensor holding plate 15g. A square hole is made to contact the conveyance plane, and a signal line for taking out a detection signal is soldered from the surface of the piezoelectric element portion 15b and the sheet metal surface of the S-shaped probe 15a to the electrical component of the apparatus. The surface of the holding plate 15g is drawn along the longitudinal direction.
[0028]
By using the S-shaped surface property detection sensor 15 configured and attached as described above, it is possible to complete the detection of the surface property of the conveyed paper at least before the fixing step and switch the fixing control. Therefore, the user can use the apparatus without worrying about the type of paper to be used, and without causing image defects or unnecessary power consumption.
[0029]
[Problems to be solved by the invention]
However, although the above configuration showed good discrimination and paper transportability at the basic examination level, there was still an incomplete part to actually use this sensor incorporated in the apparatus. Each figure in FIG. 4 shows such a malfunction that occurs in actual use.
If paper jams downstream of the sensor:
FIG. 4A is a schematic diagram for explaining a failure situation when the paper is jammed in the process after passing through the sensor, and shows the jammed paper jammed in front of the sensor. If you try to pull out the paper in the direction of the arrow in the figure to remove the jammed paper, the leading edge of the deformed jammed paper will be caught on the sensor leading edge, and if you continue to pull it out, the sensor leading edge will be deformed, or the piezoelectric element or fixed Risk of damaging the shaft.
When paper with a large curled tip is passed:
If the paper with a large paper curl is passed through the detection part of the sensor as it is, the paper front is greatly bounced up by the curled paper front as shown in FIG. After colliding with the lower part, etc., a large movement occurs, again colliding with the transport plane, causing damage due to direct collision of the piezoelectric element surface part, excessive stretching and bending of the signal line, peeling of the soldered part and its surroundings This increases the risk of generating cracks in the piezoelectric element, and also increases the floating time, thereby reducing the time for transporting the paper surface within a certain period of time, thereby reducing the detection accuracy.
If paper jams upstream of the sensor:
Since this sensor is provided with an S-shaped structure and its fixed end is rotatably fixed, even if the height of the leading edge of the paper entering the sensor is conveyed to a certain extent, the height is S-shaped. If the diameter is lower than the diameter of the lower curved portion, it does not hinder the paper conveyance. However, when the paper leading edge enters beyond the lower curved portion of the S-shape due to an abnormally large curled paper or some paper conveyance failure, FIG. As shown in C), the force that presses the sensor tip downward acts and the rotation of the sensor stops functioning, and the paper advances as it is, leading to a jam and pushing the sensor tip forward, Risk of deformation and damage.
If the paper is weaker than the sensor contact pressure:
If the contact pressure of the sensor is set to be relatively high in order to increase the detection accuracy, depending on the setting value, the sensor setting of the paper after passing may pass when some thin paper such as thin paper is passed There is a risk that local dent deformation as shown in FIG.
It is necessary to consider that problems such as these can occur during actual product use.
[0030]
The present invention has been made in view of the above problems, and the intended process is that the user does not need to select and set the paper type, and no matter what surface roughness is used, good heat treatment and fixing, An object of the present invention is to provide a heating device and an image forming apparatus using the surface property identifying apparatus capable of performing image formation efficiently, preventing failure and improving paper conveyance reliability.
[0031]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention provides a sheet material conveying means for conveying a sheet material, and a piezoelectric element.PartA probe having a fixed axis arranged perpendicular to the conveyance direction of the sheet material and parallel to the conveyance plane;WithThe fixed end of the probe isFixed shaftThe probe tip is fixed to the probe tip by a pressurizing means that pressurizes the probe tip in a circumferential direction around the fixed axis and in a direction opposite to the conveying direction of the sheet material.PartThe sheet material is conveyed while contacting the surface of the sheet material.MakeBy virtue of this, the vibration due to the vibrations and impacts according to the unevenness of the surface of the sheet material and the friction coefficient is reduced.In the piezoelectric element sectionIn the surface property identification device that induces an electrical signal to identify the surface property of the surface of the sheet material based on the electrical signal intensity difference, the probe includes a protection means for the surface of the piezoelectric element and the probe tip. And a sheet material guide means for guiding the sheet material to the probe tip, and a stopper case for restricting the amount of displacement of the probe tip.The sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from the transfer plane necessary for identification, and the upstream end of the sensor case holding plate in the transfer direction is connected to the rotating shaft for the holding plate. A holding plate pressurizing means is provided on the holding plate height regulating member so that the downstream end portion of the sensor case holding plate can be opened and closed around the rotating shaft for the holding plate and maintains the reference height. The pressure relationship between the pressure intensity P1 of the holding plate pressure means and the pressure intensity P2 of the pressure means that pressurizes the probe tip is set so that P1 >> P2, When the downstream end of the sensor case holding plate is closed, the sheet material conveying means prohibits movement of the sheet material in the direction opposite to the conveying direction, and the downstream end of the sensor case holding plate is opened. In the direction opposite to the conveying direction of the sheet material Having a sheet moving direction regulating means also movable in either directionIt is characterized by that.
  Further, the present invention comprises a sheet material conveying means for conveying a sheet material, a probe having a piezoelectric element portion, and a fixed shaft that is arranged perpendicular to the conveying direction of the sheet material and parallel to the conveying plane, The probe is fixed by a pressurizing unit that fixes a fixed end of the probe to the fixed shaft so as to be rotatable, and pressurizes the probe tip in a circumferential direction around the fixed shaft and in a direction opposite to the conveying direction of the sheet material. By conveying the sheet material while bringing the tip portion into contact with the surface of the sheet material, the piezoelectric element portion is induced by causing vibration and shock distortion having a strength corresponding to the unevenness and friction coefficient of the surface of the sheet material. In the surface property identification apparatus for generating a signal and identifying the surface property of the sheet material surface based on the difference in electric signal intensity, the probe protects the surface of the piezoelectric element and the tip of the probe. The sensor case is housed in a sensor case having a step, a sheet material guide means for guiding the sheet material to the probe tip, and a stopper means for restricting the amount of displacement of the probe tip. Is fixed to a sensor case holding plate that holds the sensor case at a reference height, and the upstream end of the sensor case holding plate in the transport direction is rotatably fixed to a rotating shaft for the holding plate. The downstream end is capable of being opened and closed about the holding plate rotating shaft and is pressed against the holding plate height regulating member by the holding plate pressurizing means so as to maintain the reference height, and the sensor case The holding plate has a sensor case rotation shaft at the downstream end of the sensor case in the transport direction, and the sensor case is fixed to be rotatable about the sensor case rotation shaft. The upstream end in the transport direction of the case is pressed against the sensor case holding plate by the sensor case pressurizing means, and the pressure strength P3 of the sensor case pressurizing means and the holding plate pressurizing means The magnitude relationship between the pressurizing strength P1 and the pressurizing strength P2 of the pressurizing unit that pressurizes the probe tip is set to satisfy P1 ≧ P3 >> P2, and the sheet material transporting unit holds the sensor case. Even in a state where the downstream end of the plate is closed, the sheet material can be moved in the direction opposite to the conveyance direction, and the sheet material moved in the opposite direction is the downstream end surface in the sheet conveyance direction of the sheet material guide means and the sheet material The sensor case pressurizing means pressurizes the sensor case upstream end so that it can swing up and down around the sensor case rotation shaft in response to the pressure that pushes back the probe tip in the direction opposite to the conveying direction. Strength P3 Is set.
[0042]
By using the surface property identification device having the above characteristics, it is possible to prevent paper conveyance failure and device failure when using a conventional heating device or an image forming device using toner, ink, or ink ribbon, and to be heated. It is possible to improve the detection accuracy of the surface characteristics of the recording material and the recording material, and to improve the reliability when optimizing the control conditions of each apparatus according to each surface property.
[0043]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0044]
<Embodiment 1>
1A to 1D are a cross-sectional view, a front view, a cross-sectional view of a paper conveyance state, and a cross-sectional view of a jam occurrence state, respectively, of the surface property identification apparatus according to Embodiment 1 of the present invention. In FIG. 1A, the same elements as those shown in FIG.
[0045]
In the present embodiment, as shown in FIG. 1A, the upper portion of the S-shaped surface property detection sensor 15 is covered with the upper cover 16, and the lower portion is covered with the front guide rib 16b, the rear guide rib 16c, and the side guide rib 16d. The S-shaped surface property detection sensor 15 is rotatably attached to a bearing portion (not shown) inside the sensor case, and the probe has an opening portion surrounded by the guide ribs. The inside is set to be able to vibrate up and down around this rotation axis. Further, the entire sensor case is fixed as a sensor case holding plate to a transfer case guide and sensor case holding plate 15g 'in which a sensor mounting hole is formed in the transfer upper guide, and the transfer flat plate 15h uses a lower transfer guide plate to reduce the number of members. The internal space of the apparatus is effectively used. In particular, a holding plate rotating shaft 15i is provided at the upstream end of the sheet conveyance upstream of the transfer case guide / sensor case holding plate, and the downstream end of the holding plate is rotated at this end. A height regulating member (not shown) is provided so as to be able to open and close around the shaft and maintain the height necessary for paper conveyance in the closed state at the front end of the holding plate.
[0046]
The main dimensions of each of the above components are: a probe having a width of 4 mm, a dimension of an opening in which the probe moves up and down is 6 mm × 6 mm, a length of the flat part of the probe is 15 mm, and a thickness of 0.2 mm. The element has a size of 3 mm × 6 mm and is bonded to a position 2 mm away from the end of the first bent portion of the flat portion toward the fixed end. The tip of the probe is pressurized with a force of 10g, and the sensor case holding plate is holding down the tip with a force of 2kg, which is two orders of magnitude stronger than this. The higher the tip is lifted, the greater the pressure.
[0047]
In the above configuration, as shown in FIG. 1 (A), the front profile rib 16b, the rear guide rib 16c, and the side guide rib 16d have a rib contour shape as viewed from the side in the conveying direction, which is the minimum required for detection of the front and rear ends of the case. 3 points above the conveyance plane by the exposure length of the probe tip (in this embodiment, the height is set to 0.5 mm, and the maximum thickness of the paper to be passed is 0.3 mm). The shape of the circular arc part of the passing circle is used. However, when the contact resistance between the paper surface and the rib surface increases, the curvature radius of the front guide rib 16b and the rear guide rib 16c may be smaller than the curvature radius of the left and right side guide ribs 16d, and the front guide rib 16b and the rear guide rib 16c. Since the corners of the lowermost point are easily caught by paper, it is preferable to round these corners with a sufficiently large radius of curvature, or a roller member that can follow these corners may be provided. .
[0048]
The probe housed in the sensor case having the above shape is such that when the paper is not present in the detection unit, the probe tip is pressed against the transport plane by a pressing means (not shown) and at the same time, the bottom surface of the probe holder. Is also in contact with the lower stopper inner wall PL provided at the downstream corner of the rear guide rib, and even if an external force is applied to push the probe tip downward, the probe tip will sink below the transport plane. Things are prevented.
[0049]
On the other hand, as shown in FIG. 1C, when the paper is passed and the probe tip is flipped up, even if the paper tip is largely curled as in the conventional example, this configuration is used. Then, the paper tip curled by the action of the rear and side guide ribs is corrected so as to be lowered to the minimum gap height necessary for detection (0.5 mm in this embodiment) and guided to the tip of the probe. At most, it can be pushed only by the leading edge of the paper with this gap height, and it is prevented that the paper is flipped up more than necessary. Even if such a configuration still causes a strong jump, the probe sheet metal plate is positioned at the position of the upper stopper inner wall PH on the inner wall on the downstream side in the transport direction inclined obliquely of the upper cover that also protects the surface of the piezoelectric element. Since the metal surface of one bent part gradually contacts and suppresses the excessive rotation of the probe while suppressing the generation of a large noise signal at the time of contact, it is possible to prevent damage to the surface of the piezoelectric element and suppress unnecessary movement of the probe. Become. At that time, the dimensions of each member are set so that the position of the probe tip that stops instantaneously is always stored inside the front, rear, left, and right guide ribs. It is also possible to prevent the tip portion from being deformed by the action of.
[0050]
Further, in this configuration, as shown in FIG. 1D, when the paper jams on the downstream side of the sensor, the second half of the paper or the next paper collides one after another toward the stopped paper leading end as shown in the figure. In this state, the opening of the sensor case of the present configuration is 10 mm × 10 mm or less. Since there is only a small hole, there is almost no danger that the tip of the probe will be pushed up by paper, and in the unlikely event that the accumulated paper pressure is high enough to cause deformation of the probe or sensor case, As described above, the downstream end portion of the holding plate is opened upward with the axis on the upstream side in the conveying direction as the center so as to release the pressure of the paper, so that deformation and damage on the sensor case side can be completely prevented. Further, the jammed paper accumulated in this portion can be easily removed by opening and closing the front end portion of the sensor holding plate.
[0051]
In this configuration, the opening / closing operation of the front end portion of the sensor case holding plate and the pressure release mechanism of the pre-transfer conveying roller 7d ′ provided upstream thereof are designed to work together. Only when it is opened upward, the pressure of the pre-transfer conveying roller 7d 'is released and the paper can be easily pulled upstream. However, when the sensor case holding plate is kept closed, the pre-transfer conveying roller 7d' The nip part of the roller pair remains pressurized, and at the same time, the roller can no longer rotate in the reverse direction, so it is very difficult to pull out the paper sandwiched between the roller pair as it is. If the paper is forcibly pulled out, the paper itself will be broken at the nip of the roller, so in the normal use method, when such a jam occurs, the user opens the sensor case holding plate upward. To remove unplug catching paper upstream to Tama, never large mechanical stresses on the probe tip is applied by this period of operation.
[0052]
<Embodiment 2>
5A, 5B, and 5C are a sectional view, a sensor holding plate lifted state sectional view, and a sensor holding plate lowered state sectional view, respectively, of the paper surface property identification device showing Embodiment 2 of the present invention. is there. In FIG. 5A, the same elements as those shown in FIG.
[0053]
In the present embodiment, as shown in FIG. 5 (A), while using a sensor having substantially the same shape as in the first embodiment, the lower stopper inner wall PL and the upper stopper inner wall PH in the sensor case of the first embodiment. An elastic downward stopper 18 and an elastic upward stopper 17 made of an elastic member are provided at positions. In this embodiment, a high-hardness rubber having a JisA hardness of 40 ° is used as the elastic member for the elastic downward stopper 18 so that the stopper function is not insufficient when this portion is too soft and the probe tip is pulled back. On the other hand, the elastic member for the elastic upward stopper 17 is made of soft low hardness rubber having a soft JisA hardness of 5 ° that can sufficiently absorb the impact so that the collision with this portion does not cause signal noise or damage to the piezoelectric element. Used. In particular, when the sensor case holding plate is greatly opened upward during jamming as shown in FIG. 5B and then closed again as shown in FIG. 5C, the height of the holding plate is not lowered slowly. If it is dropped, it will be accelerated by the force according to its height and the tip of the probe may collide with the transport plane, and it may be strongly pushed up by the reaction, and the upper stopper is hard There is a risk that the sensor may be damaged or an excessive noise signal may be generated. However, such an inconvenience can be prevented by configuring the upper stopper with a soft elastic body.
[0054]
With the above configuration, in this embodiment, the durability of the sensor and the reliability of the detection signal can be further improved. In this embodiment, rubber is used as the elastic material, but it goes without saying that other buffer materials such as maltoprene and shock absorbing gel may be used.
[0055]
<Embodiment 3>
6 (A), (B), and (C) are a sectional view, a sensor holding plate lifted state sectional view, and a sensor holding plate lowered state sectional view, respectively, of the paper surface property identification device showing Embodiment 3 of the present invention. is there. In FIG. 6A, the same elements as those shown in FIG.
[0056]
In the present embodiment, as shown in FIG. 6 (A), while using a sensor having substantially the same shape as in the first embodiment, instead of the upper stopper inner wall PH of the first embodiment, stoppers are provided above and below the probe holder 15c. Protrusion 15c 'is provided (the lower protrusion is not necessarily required as a downward stopper, and the lower surface of the probe holder may be used as it is in the above embodiment). Since it is provided closer to the rotation axis than the piezoelectric element forming portion, the tip of the probe is caused by the reaction when the tip of the sensor case holding plate is lifted as shown in FIG. 6B and dropped as shown in FIG. Even when the part is flipped upward, the probe can stop rotating by colliding with the inner wall of the sensor case with a smaller movement than stopping at the first bent part of the probe. Unwanted collision signal noise terms of it becomes possible to stop without damage and mechanical stress can be improved durability of the sensor can be suppressed. Further, since the collision is made inside the piezoelectric element forming portion, there is almost no displacement difference due to the warp of the sheet metal at the front end and the rear end of the piezoelectric element portion, and therefore internal strain is less likely to be induced. The signal itself can be reduced. In addition, by forming the protruding portion with an elastic member, collision noise can be further reduced.
[0057]
<Embodiment 4>
7A and 7B are a cross-sectional view and a sensor case lifting state cross-sectional view, respectively, of the paper surface property identification device showing Embodiment 4 of the present invention. In FIG. 7A, the same elements as those shown in FIG.
[0058]
In the present embodiment, as shown in FIG. 7A, a sensor case rotating shaft 15j is newly provided at the downstream end in the transport direction of the sensor case while using a sensor having substantially the same configuration as in the third embodiment. The sensor case is rotatably fixed on the sensor case holding plate via the rotating shaft, and the upstream end in the transport direction is pressed against the surface of the sensor holding plate with a force of 1 kg by a pressing means (not shown). Has been. By using the sensor configured as described above, when the paper jams on the downstream side in the conveyance direction of the sensor and the jammed paper is forcibly pulled out on the upstream side in the conveyance direction as shown in FIG. The pull-out pressure mainly acts on the arcuate surface facing the downstream side of the conveyance direction of the lower guide rib of the sensor case, and a part of this pressure is separated into components in the direction in which the upstream end of the sensor case is lifted upward by the action of the arc shape. When the pressure separated upward becomes higher than the pressure of the pressurizing means of the sensor case, the upstream end of the sensor case transport direction is lifted as shown in this figure, and it rotates around the rotation axis. The tip of the probe works to escape from the jam paper pull-out path, so even if you try to pull out the jammed paper in the opposite direction of the transport direction, Most force does not act on the parts, it is possible to prevent damage or deformation of the probe tip.
[0059]
At this time, the magnitude relationship of the pressure strength of each member is
“Pressure means strength of sensor holding sheet metal> Pressure means strength level of sensor case >> Pressure means strength of probe”
Therefore, at the level of the upward pressure that the probe receives from the paper during normal detection, the sensor case and sensor case holding plate act as an almost fixed rigid body for the probe. The effect is almost negligible.
[0060]
<Embodiment 5>
FIGS. 8A, 8B, and 8C are a cross-sectional view, a front view, and a sensor case lift-up cross-sectional view, respectively, of the paper surface property identification device according to Embodiment 5 of the present invention. In FIG. 8A, the same elements as those shown in FIG.
[0061]
In this embodiment, as shown in FIGS. 8A and 8B, the paper pressing roller 19 is rotated near the left and right side surfaces of the probe while using a sensor having substantially the same configuration as in the first embodiment. A roller arm 19 'fixed coaxially with the shaft and a roller pressing means (not shown) are pressed against the transport plane. As shown in the figure, the diameter of the paper presser roller is in contact with the transport plane at a position that substantially coincides with the contact position of the probe tip with the transport plane. The size is selected so that the portion exposed from the guide rib can be completely included. In this embodiment, a roller having a radius of curvature larger than the radius of curvature of the curved portion of the second bent portion of the probe is used. For this reason, the paper transported to the probe tip always comes into contact with the paper pressing roller before contacting the probe tip, so the impact of the probe on the paper tip is impacted in advance. And it is possible to prevent the occurrence of a local dent phenomenon at the paper tip due to a strong jumping of the probe by the paper tip and a collision with the probe tip as in the conventional example and other embodiments. . In particular, the above-described adverse effects are conspicuous in a high-speed machine having a high paper conveyance speed, and this configuration is an essential structure in a high-speed machine.
[0062]
In the above drawings, the paper pressing roller according to the present embodiment is applied to the configuration in which the rotation shaft is provided only on the sensor case holding plate. However, the paper pressing roller according to the present embodiment is configured according to the fourth embodiment. Needless to say, the present invention may be applied to a configuration in which a rotating shaft is provided at the downstream end of the sensor case. At this time, the paper jammed on the downstream side in the probe transport direction is to be pulled out upstream. However, the roller always comes into contact with the jammed paper to be pulled out first and presses the jammed paper down to facilitate upstream paper movement, so that the force of the jammed paper that is pulled out is less likely to act directly on the probe tip. Thus, deformation of the probe tip and sensor damage can be prevented more safely.
[0063]
In addition, the roller is pressed against the transport plane to sufficiently suppress the paper flutter and tip curl, so the probe tip is purely uneven on the paper surface. It becomes easy to detect and the detection accuracy can be improved.
[0064]
In addition, the roller of this embodiment is always at a position lower than the lowest point of the probe tip by a distance t when the tip of the sensor case holding plate is lifted as shown in FIG. 8C by setting the movable range of the arm. The lowermost point of the roller is positioned so that when the tip of the sensor case holding plate is lowered, it always comes into contact with the transport plane first from the roller. Even if the probe is dropped after being lifted up, the probe will come into contact with the transfer plane after the roller collides and alleviates the impact before the probe tip hits the transfer plane. Deformation of the probe tip and sensor damage can be prevented.
[0065]
<Embodiment 6>
FIGS. 9A, 9B, and 9C are a cross-sectional view, a cross-sectional view of the sensor case in the middle of lifting the sensor case, and a cross-sectional view in the completed state of lifting the sensor case, respectively, illustrating Embodiment 6 of the present invention. . In FIG. 9A, the same elements as those shown in FIG. 1A are denoted by the same reference numerals.
[0066]
In the present embodiment, as shown in FIG. 8A, a probe protection shutter 20 and a shutter joint are provided at the distal end portion on the downstream side in the transport direction of the sensor case while using the sensor and sensor case having substantially the same configuration as in the first embodiment. 20a, a shutter arm 20b, a shutter arm rotating shaft 20c, and a shutter tip roller 20d are provided. The shutter arm is applied with a pressing force similar to the probe contact pressure by a pressing means (not shown) provided on the fixed shaft. A force that can be pushed downward is constantly acting.
[0067]
In a normal state, the probe shutter 20 is housed in front of the sensor case as shown in FIG. 8A, and presses the paper conveyed by a roller at the tip (the diameter of the roller is also larger than the exposed length of the probe). Therefore, the paper is prevented from entering the upper part of the shutter.
[0068]
As shown in FIG. 9B, this probe protection shutter moves so as to lower the probe protection shutter downward by the action of the pressurizing means when the front end of the sensor case holding plate is lifted during jam processing ( At this time, the shutter arm moves through a groove (not shown) opened in the sensor case), and the shutter arm is set so that the shutter joint portion stops at the downstream end in the transport direction of the probe opening (depending on the groove of the arm). Since either the regulation or regulation by the shutter joint coming into contact with the front guide rib may be used), the probe protection shutter is set so as to face vertically downward by the weight of the roller at the tip. In the state where the tip of the holding plate is lifted above the vertical as shown in FIG. Since probe shutter moves completely to cover the opening of the probe, the user is forcibly unless lift the shutter upward, is no longer possible to touch the probe tip directly.
[0069]
On the other hand, when lowering the front end of the sensor case holding plate after jamming, the applied pressure applied to the front end of the sensor case holding plate is sufficiently larger than the applied pressure acting on the shutter arm, so The contact roller at the front end of the shutter acts to push up the shutter joint, and the shutter arm is not pressurized enough to resist this force, so the probe protection shutter is transported again to the sensor case while it is bent at the shutter joint. It comes to be accommodated in the tip portion on the downstream side in the direction.
[0070]
In this embodiment, since the user cannot carelessly touch the probe in this way, the probe tip can be protected under any conditions by using it in addition to the probe protection configuration of each of the above embodiments. Thus, sufficient performance and durability can be maintained in any actual use situation.
[0071]
<Embodiment 7>
FIG. 10 is a sectional view of an ink jet image forming apparatus showing Embodiment 7 of the present invention.
[0072]
In the present embodiment, a paper surface roughness detection sensor unit 25 in which components including a sensor case for storing the S-shaped surface property detection sensor according to the present invention and a sensor case holding plate are unitized is applied to an ink jet printer. An ink jet printer 21 with a paper type detection function is configured. In this cross-sectional structure, this apparatus is composed of a paper feed tray 22, an ink jet paper feed roller 23, a paper guide 24, a pinch roller pair 26, a recording head 27, a platen 28, a paper discharge roller pair 29, etc. After receiving the signal, the paper on the paper feed tray 22 is transported to the pinch roller pair 26 by the paper feed roller 23, and the paper is transported to the platen 28 by the necessary feed amount by the operation of the pinch roller pair 26. After the recording head 27 forms an image on the paper in the feed area, the paper is sequentially fed by the operation of the pinch roller pair 26 part, and the recorded paper is nipped and conveyed by the paper discharge roller pair 29 part, so that the entire image After the formation is completed, the paper is finally discharged.
[0073]
In this embodiment, the sensor unit 25 is disposed at a position opposite to the paper guide 24 part between the paper feed roller pair 23 part and the pinch roller pair 26 part, and the paper leading end part is moved from the paper feed part in the initial printing operation. By conveying the surface of the paper until it is conveyed to the pinch roller pair 26 part, the surface roughness or frictional resistance of the paper is detected and the paper type is identified. By forming an image with a reduced amount, ink can be saved and bleeding can be prevented from flowing to unnecessary parts.Conversely, for paper with a rough surface, the ink can penetrate into the lower layer of the paper. By switching the control to increase the amount of protrusion of ink, it is possible to prevent the occurrence of problems such as density reduction, and so on, so that the control amount of image forming conditions such as the amount of ink protrusion suitable for each paper type can be switched. And it has a function.
[0074]
In addition, as a sensor for this type of application, a device for identifying a paper type by detecting a difference in glossiness of the paper surface using an optical sensor has already been developed in some models. Requires a large number of components, such as light sources, optical systems such as lenses and filters, and photoelectric conversion elements such as photodiodes and CCDs. Since accuracy is required, the cost is likely to increase, and further, the performance is greatly affected by contamination of the optical system.
[0075]
On the other hand, the sensor of the present invention can be constructed at a low cost with a general-purpose member in which sheet metal, piezoelectric elements, etc. are widely used, and the surface of the sensor detection part is automatically cleaned by the paper surface every time paper is passed. In addition, even if dust or dirt adheres to other parts, there is basically no effect on performance, and even if there is any chance, it will be shaken off by vibrations that occur, so there is no need to worry about performance deterioration due to dirt, Excellent in terms of reliability.
[0076]
<Eighth embodiment>
FIG. 11 is a sectional view of a thermal head type image forming apparatus showing Embodiment 8 of the present invention.
[0077]
In the present embodiment, a paper type detection function is provided using a paper surface roughness detection sensor unit 25 in which components including a sensor case for storing the S-shaped surface property detection sensor according to the present invention and a sensor case holding plate are unitized. A thermal head printer 30 is configured. The thermal head type image forming apparatus in this embodiment is composed of an ink ribbon 33, a pair of ink ribbon transport rollers 31, a thermal head 32, a head facing plate / paper transport guide 34, and the like, and usually receives a print signal. The paper 7 is transported to the nip portion between the head facing plate / paper transport guide 34 and the ink ribbon transport roller 31 on the paper feed side by a paper feed roller and paper transport roller (not shown), and is sandwiched between the ink ribbon 33 and the guide 34. After that, the ink ribbon 33 is conveyed to the head portion while being in close contact with the ink ribbon 33, and necessary power is supplied to the head portion according to the print signal to heat and melt the ink layer 33 ′ on the ink ribbon 33. After the ink image 33 ″ is formed on the paper by thermally transferring it to the paper surface, it is sequentially fed by the operation of the transport roller section. And it is configured to be issued.
[0078]
In the present embodiment, the sensor unit 25 is disposed at a position opposite to at least the guide 34 portion and the guide portion 34 before the nip portion of the ink ribbon transport roller 31 on the paper feeding side, and the paper is fed from the paper feeding portion at the initial stage of the printing operation. By detecting the surface roughness or frictional resistance of the paper by conveying the surface of the paper until the leading edge is conveyed to the nip, the paper type is identified. Since heat transfer can be performed with low power due to better conduction, the control is switched to reduce the power supplied to the ink head. On the contrary, in the case of paper with a rough surface, the thermal conductivity decreases and the rough surface In order to transfer the ink sufficiently, it is necessary to lower the viscosity of the ink. Therefore, it is possible to switch the control so as to sufficiently reduce the viscosity of the ink with higher power, etc. It is possible to switch between the control amount of the electric power.
[0079]
【The invention's effect】
  As is apparent from the above description, according to the present invention, the piezoelectric elementPartA fixed end of a probe having a surface of the sheet material is fixed to a fixed shaft that is perpendicular to the transport direction of the sheet material and parallel to the transport plane, and the probe tip is circumferentially centered on the fixed shaft and By using a pressurizing means that pressurizes the sheet material in a direction opposite to the conveying direction, the sheet is conveyed while being brought into contact with the surface of the sheet material. In the surface property identification device that induces distortion due to the electric field to generate an electric signal and identifies the surface property of the sheet material surface based on the electric signal intensity difference, the probe protects the surface of the piezoelectric element and the tip of the probe Sensor having a function and a sheet material guide function for smoothly guiding the sheet material to the probe tip and a stopper function for suppressing excessive displacement of the probe tip unnecessary for identification So as to be accommodated in the over vinegar,The sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from the transfer plane necessary for identification, and the upstream end of the sensor case holding plate in the transfer direction rotates around the holding plate rotation shaft. The downstream end of the sensor case holding plate can be opened and closed about the holding plate rotating shaft, and the holding plate height restricting member is held by a holding plate pressurizing means so as to maintain the reference height. The magnitude relationship between the pressure intensity P1 of the holding plate pressure means and the pressure intensity P2 of the pressure means that pressurizes the probe tip is set so that P1 >> P2 The material conveying means prohibits movement of the sheet material in the direction opposite to the conveying direction when the downstream end of the sensor case holding plate is closed, and when the downstream end of the sensor case holding plate is opened. The sheet material is in a direction opposite to the conveying direction. By having the sheet material moving direction regulating means allowing also moving in the direction of the deviation, the effect is obtained that it becomes possible to maintain a satisfactory performance and durability even in a situation that is actually used.
  In addition, this sensor case itself is fixed so that it can be rotated back and forth, and paper pressing rollers are provided on both sides of the probe tip, and the probe surface is covered with a protective shutter when the user may touch it during jam processing. As a result, the probe tip is protected under any conditions, and it is possible to maintain sufficient performance and durability in any actual use situation. .
[Brief description of the drawings]
FIG. 1A is a cross-sectional view of a surface property identification apparatus according to Embodiment 1 of the present invention;
(B) is a front view,
(C) is a cross-sectional view of the paper transport state,
(D) is a cross-sectional view of a jam occurrence state
It is.
FIG. 2 is a cross-sectional view of a conventional electrophotographic image forming apparatus.
FIG. 3A is a sectional view of a paper conveyance path of a conventional S-shaped surface property detection sensor;
(B) is a top view.
It is.
FIG. 4A is a cross-sectional view when the paper jams on the downstream side of the paper conveyance path of the S-shaped surface property detection sensor;
(B) is a cross-sectional view when the leading curled paper enters the paper conveyance path of the S-shaped surface property detection sensor,
(C) is a cross-sectional view when paper jams on the upstream side of the paper conveyance path of the S-shaped surface property detection sensor,
(D) is a top view when dents are generated at the leading edge of the paper.
It is.
FIG. 5A is a cross-sectional view of a paper surface property identification apparatus according to Embodiment 2 of the present invention;
(B) is a sectional view of the sensor holding plate lifted,
(C) is a sectional view of the sensor holding plate lowered
It is.
FIG. 6A is a cross-sectional view of a paper surface property identification apparatus according to Embodiment 3 of the present invention;
(B) is a sectional view of the sensor holding plate lifted,
(C) is a sectional view of the sensor holding plate lowered
It is.
FIG. 7A is a sectional view of a paper surface property identification apparatus according to Embodiment 4 of the present invention;
(B) is a sectional view of the sensor case lifted up
It is.
FIG. 8A is a sectional view of a paper surface property identification apparatus according to Embodiment 5 of the present invention;
(B) is a top view,
(C) is a sectional view of the sensor holding plate lifted up
It is.
FIG. 9A is a cross-sectional view of a paper surface property identification apparatus according to Embodiment 6 of the present invention;
(B) is a sectional view of the sensor holding plate in the middle of lifting,
(C) is a sectional view of the sensor holding plate lifting completed
It is.
FIG. 10 is a cross-sectional view of an ink jet printer with a paper type detection device according to a seventh embodiment of the present invention.
FIG. 11 is a sectional view of a thermal head printer according to an eighth embodiment of the present invention.
[Explanation of symbols]
1 Charging roller
2 Photosensitive drum
3 Exposure means
4 Developer
5 Toner
7 Recording material
10 Transfer roller
12 Fixing device
15 S-shaped surface detection sensor
15c probe holder
15c 'Stopper projection
15e Probe rotation axis
15g sensor holding plate
15g 'transfer upper guide and sensor case holding plate 15g'
15h Transport plate
15i Holding plate rotation axis
15j Rotating shaft for sensor case
16 Sensor case
16a Sensor case top cover
16b Front guide rib
16c Rear guide rib
16d Side guide rib
17 Elastic upper stopper
18 Elastic downward stopper
19 Paper roller
19 'roller arm
20 Probe protection shutter
20a Shutter joint
20b Shutter arm
20c Shutter arm rotation axis
20d shutter tip roller
21 Inkjet printer
27 Recording head
30 Thermal head printer
33 Ink Ribbon
32 Thermal head

Claims (15)

A sheet conveying means for conveying the sheet material, a probe having a piezoelectric element, and a fixed shaft arranged in parallel at right angles and the transport plane in the conveying direction of the sheet material, the fixed end portion of the probe the rotatably fixed to the fixed shaft, by pressurizing the pressure means in the direction opposite to the conveying direction of the circumferential direction and the sheet material of the probe tip around the fixed shaft, the said probe tip sheet By causing the sheet material to be conveyed while being in contact with the material surface, an electrical signal is generated by inducing distortion in the piezoelectric element portion by vibration and impact having a strength according to the unevenness and friction coefficient of the sheet material surface, In the surface property identification device for identifying the surface property of the sheet material surface based on the electric signal intensity difference,
The probe has a sensor case having protection means for the surface of the piezoelectric element and the probe tip, sheet material guide for guiding the sheet material to the probe tip, and stopper means for restricting the amount of displacement of the probe tip. It is housed in,
The sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from the transfer plane necessary for identification, and the upstream end of the sensor case holding plate in the transfer direction rotates around the holding plate rotation shaft. The downstream end of the sensor case holding plate can be opened and closed about the holding plate rotating shaft, and the holding plate height restricting member is held by a holding plate pressurizing means so as to maintain the reference height. The magnitude relationship between the pressurizing strength P1 of the holding plate pressurizing means and the pressurizing strength P2 of the pressurizing means that pressurizes the probe tip is set to satisfy P1 >> P2.
When the downstream end portion of the sensor case holding plate is closed, the sheet material conveying means prohibits movement of the sheet material in the direction opposite to the conveying direction, and opens the downstream end portion of the sensor case holding plate. The surface property identification apparatus according to claim 1, further comprising a sheet material movement direction restricting unit that enables the sheet material to move in any direction opposite to a conveyance direction .   2. The surface property identification apparatus according to claim 1, wherein an upper cover is provided on the surface of the sensor case as the piezoelectric element surface protection means of the sensor case, the probe tip portion protection means and the probe under the sensor case as the sheet material guide means. Seat guide ribs on the left and right and front and rear of the movable range, and stopper means for restricting the amount of displacement of the probe tip, contact the non-piezoelectric element forming surface of the probe inside the sensor case, and the probe tip is more upward than necessary. An upper stopper inner wall for preventing rotation and a lower stopper inner wall for preventing the probe tip from rotating more than necessary are provided, respectively, and upward displacement is restricted by the upper stopper inner wall. The position of the probe tip in the case of the inner side of the sheet guide rib, the lower stopper The surface property identification device, wherein the position of the probe tip when the downward displacement is regulated by a wall is regulated to a position exposed by a minimum length necessary for identification from the surface of the sheet guide rib. . The apparatus of claim 1, wherein the sheet moving direction regulating means of the sheet conveying means has a roller pair of the conveying rollers in contact with the driven roller pressure圧当to rotate only in the sheet conveying direction, the sheet The material movement direction regulating means includes a release mechanism for releasing the pressure of the roller pair in accordance with an operation of opening the downstream end of the sensor case holding plate. A sheet material conveying means for conveying the sheet material; a probe having a piezoelectric element portion; and a fixed shaft disposed at right angles to the conveying direction of the sheet material and parallel to the conveying plane. The probe tip is fixed to the fixed shaft, and the probe tip is pressed by a pressurizing unit that pressurizes the probe tip in a circumferential direction about the fixed shaft and in a direction opposite to the conveying direction of the sheet material. By causing the sheet material to be conveyed while being in contact with the material surface, an electrical signal is generated by inducing distortion in the piezoelectric element portion by vibration and impact having a strength according to the unevenness and friction coefficient of the sheet material surface, In the surface property identification device for identifying the surface property of the sheet material surface based on the electric signal intensity difference,
The probe has a sensor case having protection means for the surface of the piezoelectric element and the probe tip, sheet material guide for guiding the sheet material to the probe tip, and stopper means for restricting the amount of displacement of the probe tip. Stored in
The sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from the transfer plane necessary for identification, and the upstream end of the sensor case holding plate in the transfer direction rotates around the holding plate rotation shaft. The downstream end of the sensor case holding plate can be opened and closed about the holding plate rotating shaft, and the holding plate height restricting member is held by a holding plate pressurizing means so as to maintain the reference height. While being in pressure contact, the sensor case holding plate has a sensor case rotation shaft at the downstream end of the sensor case in the transport direction, and the sensor case is rotatable about the sensor case rotation shaft. The upstream end of the sensor case in the transport direction is in pressure contact with the sensor case holding plate by the sensor case pressurizing unit, and the pressure intensity P3 of the sensor case pressurizing unit and the holding plate Addition The magnitude relation between the pressurized pressure strength P2 of the pressurizing means for pressurizing the probe tip and the pressing pressure strength P1 means is set to be P1 ≧ P3»P2, and, the sheet material conveying means said sensor Even when the downstream end of the case holding plate is closed, the sheet material can be moved in the direction opposite to the conveyance direction, and the sheet material moved in the opposite direction is the downstream end surface in the sheet conveyance direction of the sheet material guide means. And the sensor case pressurizing means so that the upstream end of the sensor case can be swung up and down around the rotation axis for the sensor case according to the pressure that pushes back the tip of the probe in the direction opposite to the conveying direction. A surface property identification device in which a pressure strength P3 is set. The apparatus of any of claims 1 to 4, wherein the sensor case has a sheet pressing roller for pressing the sheet material to the conveying plane on the left and right sides of the probe, the sheet hold-down diameter of the roller is at least the probe The length of the tip of the sheet material guide means that is longer than the exposed length of the sheet material guide means , and the position of the contact position of the sheet pressing roller with respect to the transport plane relative to the transport direction is the transport of the contact position of the probe tip with the transport plane. The probe tip always fits within the contour viewed from the side of the conveyance direction formed by the sheet pressing roller and the sheet material guide means , and the sensor case holding plate is opened to open the sensor case. When the upstream end of the holding plate is lifted, the lower end of the sheet pressing roller is always held at a position lower than the probe tip. Is, the sensor case holding plate surface property identification apparatus, characterized in that it is configured to contact the conveying plane above the said sheet hold-down roller is in close. The apparatus of any of claims 1 to 5, wherein the stopper inner wall surface of the identification device, characterized by being composed of an elastic member. 7. The apparatus according to claim 1 , wherein the probe is rotatably fixed to the fixed shaft via a probe holder in which the probe can be attached and detached, and the probe holder portion rotates as the stopper means. A surface property identification apparatus using a probe holder with a stopper function provided with a regulating shape, wherein the probe holder with a stopper function is in contact with upper and lower inner walls of a sensor case in the vicinity of the fixed shaft. The apparatus according to any one of claims 1 to 7 , wherein the sensor case is housed on the upstream side of the sheet material guide means with the sensor case holding plate closed, and the sensor case holding plate is opened with the sensor case holding plate opened. A surface property identification apparatus, comprising: a probe protection shutter that functions to move so as to prevent exposure of a probe tip and cover the probe. The apparatus according to any one of claims 1 to 8 , wherein the sheet material guide means is on a vertical line that is lowered from the front and rear ends of the sensor case in the conveyance direction and from the center of the sensor case to the conveyance plane when viewed from the side in the conveyance direction. An abutting position of the probe tip portion with the conveyance plane, having an arc-shaped rib shape that substantially coincides with an arc of a circle passing through three points at a height position from the conveyance plane that is the minimum necessary for conveyance of the sheet material Is not provided on the downstream side in the transport direction from the lowest point of the arc-shaped rib. The probe according to any one of claims 1 to 9 , wherein the probe is formed at two locations, a first bent portion R1 and a second bent portion R2, so that the tip end portion of the metal sheet metal is S-shaped when viewed from the side surface in the transport direction. using S-shaped sheet metal folding, S-shaped probe formed with the piezoelectric element portion on the flat portion surface between the fixed end of the S-shaped metal plate and the first bent part, at least the second bent portion The surface property identification apparatus characterized in that the most upstream point in the transport direction of R2 is housed inside the sheet material guide means . And surface property identification device according to any one of claims 1 to 10, a heat treatment means for contact heating on the material to be heated which has passed through the surface of the identification device, wherein the heat treatment in accordance with the identification signal of the surface property identification device A heating apparatus comprising control means for controlling the heating temperature of the means. A surface property identification device according to any one of claims 1 to 10 , image forming means for forming a toner image on a recording material that has passed through the surface property identification device, and heating the recording material on which the toner image is formed. An image forming apparatus comprising: a fixing unit that pressurizes and fixes the toner image on the recording material; and a control unit that controls a fixing temperature of the fixing unit in accordance with an identification signal of the surface property identification device. . A surface property identification device according to any one of claims 1 to 10 , image forming means for forming a toner image on a recording material that has passed through the surface property identification device, and heating the recording material on which the toner image is formed. A fixing unit that pressurizes and fixes the toner image on the recording material; and a control unit that changes a heating time or a heating processing interval of the recording material in accordance with an identification signal of the surface property identification device. Image forming apparatus. And surface property identification device according to any one of claims 1 to 10, and the ink ejection type image forming means for forming an image by ejecting ink onto a recording material having passed through the surface of the identification device, wherein the surface property identification An image forming apparatus comprising control means for controlling an ink discharge amount of the ink discharge type image forming means in accordance with an identification signal of the apparatus. And surface property identification device according to any one of claims 1 to 10, and the thermal transfer image forming means for thermally transferring the ink on the ink ribbon using a thermal head on a recording material having passed through the surface of the identification device, wherein An image forming apparatus comprising: control means for controlling power supplied to the thermal head of the thermal transfer image forming means in accordance with an identification signal of a surface property identification apparatus.

Images