JP2003175589A - Inkjet printer - Google Patents

Abstract

[PROBLEMS] To prevent crosstalk without increasing the size of an apparatus in an ink jet printer that reciprocates a head in a width direction of a recording medium and energizes the head via a flat cable. SOLUTION: An FPC 43 is attached to each tube 31 protruding from both end surfaces in the moving direction of a head 7. For this reason, the FPC 43 is divided into two,
The divided FPCs 43 can be satisfactorily isolated from each other. Crosstalk does not occur between the FPCs 43 thus divided. Also, the occurrence of crosstalk in the FPC 43 attached to each tube 31 can be satisfactorily prevented because the number of patterns is divided into two. Further, since each FPC 43 is attached to the tube 31 via the tube band 41, its behavior is
Can be stabilized in the same manner as described above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer for forming an image on a recording medium by ejecting ink from the head, and more specifically, the head is reciprocated in the width direction of the recording medium and the head is reciprocated. The present invention relates to an inkjet printer that discharges ink by energizing a printer.

[0002]

2. Description of the Related Art Conventionally, in an ink jet printer, a head for ejecting ink is mounted on a head moving means such as a carriage, and an image is formed while reciprocating in a width direction of a recording medium. In addition, since this type of head generally discharges ink in response to energization of a drive signal, the head is energized via a flat cable such as FFC or FPC. FFC
The FPC and the FPC are excellent in flexibility and can cope well with the movement of the head.

[0003]

However, in recent years, in order to meet the demand for higher speed in inkjet printers, the ejection frequency has been increased and the number of head pins has been increased. For this reason, the frequency of the drive signal to be energized is increased due to the higher frequency, and the number of patterns is also increased due to the increase in the number of head pins. Therefore, FFC, FP
When C is bundled into one and energized, so-called crosstalk occurs in which noise is superimposed between patterns due to energization to other patterns. When this crosstalk occurs, ink ejection timing may shift or the waveform may be greatly disturbed and ink ejection may not be stable, even if a malfunction does not occur.

As a measure against crosstalk, conventionally,
The methods of increasing the distance between patterns or increasing the thickness of the pattern have been adopted, but in these methods, FFC and FPC are used.
Has a large cross-sectional area, resulting in reduced flexibility. For this reason,
Today, the number of head pins has increased
There are also situations where there is no choice but to take a heavy placement method. In this way, when FFC and FPC are arranged in double,
Crosstalk is more likely to occur. It is also conceivable to mount a large-capacity capacitor on the head to remove noise, but in this case, the device becomes large.

Therefore, according to the present invention, in an ink jet printer which reciprocates the head in the width direction of the recording medium and energizes the head through a flat cable, it is possible to prevent crosstalk without increasing the size of the apparatus. It was done as a purpose.

[0006]

In order to achieve the above-mentioned object, the invention according to claim 1 is a head for ejecting ink to form an image on a recording medium, and the head is different. An ink jet printer comprising a tube for supplying ink to the head from an ink holding portion provided on the body, and a head moving means for reciprocating the head in the width direction of the recording medium, wherein the tube is
A flat cable for energizing the head is attached to each of the tubes protruding from both end surfaces in the moving direction of the head and protruding from both end surfaces.

In the present invention thus constituted, the tubes for supplying the ink to the head from the ink holding portion provided separately from the head respectively project from both end surfaces in the moving direction of the head. Therefore, it is possible to favorably respond to a case where there is a strong demand for thinning the inkjet printer, such as a case where the mobile printer is made compact. Also, for each tube protruding from the both end surfaces,
A flat cable for energizing the head is attached to each head.

Therefore, in the present invention, the flat cable can be divided into two, and the divided flat cables can be well separated from each other. Crosstalk does not occur between the flat cables divided in this way. In addition, the occurrence of crosstalk in the flat cable attached to each tube can be effectively prevented because the number of patterns is divided into two. Furthermore, since each flat cable is attached to the tube, its behavior can be stabilized.

Therefore, according to the present invention, crosstalk can be prevented without increasing the size of the device. That is, by maintaining the cross-sectional area of each flat cable small, it is possible to ensure its flexibility and prevent crosstalk without using a large capacitor. Further, as the behavior of the flat cable is stabilized as described above, its durability can be improved satisfactorily and the load on the carriage motor can be reduced. Therefore, the inkjet printer of the present invention can form an extremely accurate image.

According to a second aspect of the present invention, in addition to the structure of the first aspect, a binding member for bundling and holding the tube and the flat cable is provided.
In the present invention, since the tube and the flat cable are bundled by the binding member, the behavior of each flat cable can be integrated with the tube, and the behavior can be further stabilized. Therefore, according to the present invention, in addition to the effect of the first aspect of the invention, the durability of the flat cable is further improved, and the load on the carriage motor is further reduced, so that a more accurate image can be formed. Occurs.

According to a third aspect of the invention, in addition to the structure of the second aspect, the binding member holds either the tube or the flat cable so as to be movable in the longitudinal direction, and the tube or the flat cable. The bundling position of the bundling member is configured to be displaceable.

In the present invention, since the binding member holds either the tube or the flat cable so as to be movable in the longitudinal direction, the binding position of the tube or the flat cable by the binding member can be displaced. Therefore, even if the tube and the flat cable have different curvatures at the curved portion of the tube, no twist or the like occurs. Therefore, it is possible to further suppress the addition of the movement resistance from the tube to the head. Therefore, in the present invention, in addition to the effect of the second aspect of the invention, there is an effect that the load of the carriage motor can be more favorably reduced and a more accurate image can be formed.

According to a fourth aspect of the present invention, in addition to the structure according to any one of the first to third aspects, it is attached to the tube and is formed into a strip shape with the width direction facing the recording medium. It is characterized by further comprising a protective film for suppressing the bending of the tube toward the recording medium.

In the present invention, a protective film formed in a strip shape with the width direction facing the recording medium is attached to the tube,
The bending of the tube in the direction of the recording medium is suppressed. Therefore, it is possible to favorably prevent the tube and the flat cable from coming into contact with the recording medium, and it is possible to further smoothly bend the tube and the flat cable. Therefore, in the present invention, in addition to the effects of the invention according to any one of claims 1 to 3, contamination of the recording medium can be prevented better, and the load on the carriage motor can be reduced more favorably. The effect that a different image can be formed occurs.

According to a fifth aspect of the invention, in addition to the structure of the fourth aspect, the protective film protects the flat cable by covering it from the side opposite to the tube. In the present invention, the protective film protects the flat cable by covering it from the side opposite to the tube,
In addition to the effect of the invention as set forth in claim 4, there is an effect that the flat cable can be more favorably protected.

According to a sixth aspect of the present invention, in addition to the structure of the fifth aspect, a binding member for holding the protective film in a bundle with the tube and the flat cable is provided, and the binding member is the flat cable and the flat cable. It is characterized in that either the protective film or the tube is movably held in the longitudinal direction, and the flat cable and the protective film or the binding position of the tube by the binding member can be displaced.

In the present invention, since the protective film is bound with the tube and the flat cable by the binding member,
The bending behavior of the tube and the flat cable can be further smoothed. Further, since the binding member of the present invention holds one of the flat cable and the protective film or the tube so as to be movable in the longitudinal direction, the binding position of the flat cable and the protective film or the tube is displaced by the binding member. It will be possible.

Therefore, even if the curvature of the curved portion of the tube is different from that of the flat cable and the protective film, no twisting occurs. Therefore, it is possible to further suppress the addition of the movement resistance to the head. Therefore, in the present invention, in addition to the effect of the fifth aspect of the invention, there is an effect that the load of the carriage motor can be further reduced and a more accurate image can be formed.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of the internal structure of an inkjet printer to which the present invention is applied, as viewed from the paper discharge side, that is, from the downstream side in the recording paper conveyance direction (hereinafter referred to as the front side), and FIG. FIG. 3 is a perspective view seen from the paper side, that is, the upstream side (hereinafter referred to as the rear side) in the recording paper conveyance direction.

As shown in FIG. 2, a paper feed roller 1 is provided at the rear of the ink jet printer, and recording papers (corresponding to recording media) held in a stacked manner in a paper feed tray (not shown) one by one. Separate and transport. The recording paper sent from the paper feed roller 1 is carried onto the platen 5 by the carrying roller 3 shown in FIG. 1, an image is formed by the head 7, and then discharged onto a paper discharge tray (not shown) by the paper discharge roller 9. To be paper.

As shown in FIG. 3 which is a sectional view taken along the line AA of FIG. 1 and FIG. 4 which is a sectional view taken along the line BB of FIG. 3, the head 7 is mounted on the carriage 11, and the carriage 11 is mounted on the carriage 11. Are guided by a guide shaft 13 and the like so as to be movable in the width direction (main scanning direction) of the recording paper. The carriage 11 is connected to an endless belt 17 driven by a carriage motor 15 as a head moving means, and moves on the platen 5 in the width direction according to the rotation of the carriage motor 15. Further, an encoder strip 19 is stretched in the width direction behind the guide shaft 13,
A known linear encoder is configured in cooperation with an optical sensor (not shown) provided on the carriage 11.

Further, as shown in FIG. 4, a roller 21 for pressing and sandwiching the recording paper with the conveying roller 3 is disposed below the conveying roller 3, and the roller 21 is formed by a spring (not shown). It is biased upward together with the pressing roller holder 23. Further, a cover 25 made of a thin metal plate is arranged on the outer periphery of the upper portion of the transport roller 3 to prevent the transport roller 3 from coming into contact with the tube 31 described below.

The front end face of the cover 25 and the guide shaft 1
The front end face of 3 is disposed on a vertical plane perpendicular to the platen 5 as shown in FIG. In addition to the above, various members such as a paper presser 27 made of a leaf spring for pressing the recording paper against the platen 5 are arranged on the platen 5.

Next, as shown in FIG. 5 which is an enlarged view of the portion C of FIG. 3, tubes 31 for supplying ink to the head 7 from both end faces in the moving direction of the head 7 are forward from the moving direction. It projects in a direction inclined by about 30 °. The tube 31 is provided with two tubes 31 for supplying magenta and yellow ink to the head 7 in combination on one side, and on the other side, it supplies cyan and black ink to the head 7. Book tube 31
Are arranged in combination at the top and bottom. Then, these tubes 31 are connected to the head 7 via the following manifold 33.

FIG. 6 is a plan view showing the structure of the manifold 33, a side view, and a sectional view taken along the line DD. As shown in FIG. 6, the manifold 33 has a conical shape with a small insertion-side diameter on the insertion side along the protruding direction (mounting direction) of the tube 31, and has a pipe portion 35a rather than the rear end of the conical portion. A valve 35 having a smaller diameter is protruded, and the ink supplied here is supplied from a supply port 37 to a nozzle (not shown) of the head 7 for each color. Further, the manifold 33 is provided with an 8-shaped holding member 39 having two hollow portions into which the tubes 31 are fitted, and is fitted and fixed so that the above-mentioned valve 35 is arranged in the hollow portions. Has been done. The holding member 39 connects the tube 31 to the valve 35.
Since it is necessary to press the tube 31, the tube 31 is made of a material harder than the tube 31, and the holding member 39 is assembled while the tube 31 is inserted into the valve 35. In the manifold 33 thus configured, the outer circumference of the tube 31 is the holding member 39 and the inner circumference is the valve 35.
Therefore, the tube 31 can be surely fixed because they are pressed respectively.

Further, the above-mentioned two tubes 31 are respectively shown in FIG.
The FPC 43 (corresponding to a flat cable: may be FFC) and the FPC protective film (hereinafter simply referred to as a protective film) 45 are bundled at various places by a tube band 41 as a binding member as shown in FIG.

The tube band 41 is made of an elastic material such as rubber or synthetic resin having elasticity, and has a pair of grooves 47 and one groove 49 as shown in FIG. The groove 47 has a cleat formed on the inner surface, and immobilizes the tube 31. On the other hand, the groove 49 loosely fits the FPC 43 and the protective film 45 and has a retaining portion 60 to hold them movably in the longitudinal direction. In addition, FPC
43 is disposed between the pair of tubes 31 and the protective film 45, and is protected by the protective film 45. Further, the protective film 45 is provided with rectangular notches 45a at both ends of the attachment portion to the tube band 41, and the protective film 45 is held movably in the longitudinal direction within the range of the notches 45a.

An inclined surface 48 is formed on a portion of the tube band 41 facing the retaining portion 60, and a protrusion 61 is formed on the tip of the retaining portion 60. The length of the groove 49 in the longitudinal direction (vertical direction) is the FPC 43 or the cutout portion 45a.
It is longer than the width of the protective film 45 where the cutout is formed, and shorter than the width of the protective film 45 where the cutout portion 45a is not formed. The protective film 45 and the FPC 43 are guided by the slope 48 provided on the tube band 41 and guided to the groove 49 while bending, and when the entire width enters the groove 49, the bending is released. (At this time, it goes without saying that the retaining portion 60 of the tube band 41 may be temporarily retracted against the elasticity of the tube band 41.) The FPC 43 with the bending released, the protective film 45
Since the stopper portion 60 and the protrusion 61 prevent movement toward the slope 48 side, the stopper portion 60 and the protrusion 61 do not slip out of the groove 49.

Further, as shown in FIG. 5, the FPC 43 and the protective film 45 are guided to the rear end surface of the head 7,
43 is folded back at this rear end face and introduced into the head 7 and the above-mentioned optical sensor, and the protective film 45 passes through to the opposite side as it is along the rear end face. It should be noted that FIG. 8 schematically shows the above-described folding method of the FPC 43, so refer to it.

Next, as shown in FIGS. 1 to 3, the platen 5
A pair of columnar support portions 51 are provided in the center front of the
Plate-shaped tube guides 53 for preventing the tubes 31 from protruding forward are continuously provided on the left and right sides thereof.
As described above, the tube 31, the FPC 43, and the protective film 45 protruding from both end surfaces of the carriage 11 in the moving direction are
It is guided to the support portion 51 while being bundled at various places by the tube band 41, folded back at the support portion 51, fixed along the front surface of the tube guide 53, and guided left and right. The tube 31 passes through the left and right guide pieces 55 to an ink cartridge (not shown: corresponding to an ink holding portion) provided below the platen 5, and the FPC 43 passes below the platen 5 through the guide groove 57. To the control circuit (not shown).

In the ink jet printer of this embodiment having the above-described structure, the head 31 moves together with the carriage 11 to bend the tube 31 as shown by the phantom line in FIG. At this time, the forward bending of the tube 31 is restricted by the tube guide 53 as described above. Further, the backward bending of the tube 31 is restricted by the protective film 45 or the tube band 41 coming into contact with the guide shaft 13 and the cover 25.

Further, in the present embodiment, the FPC is attached to each tube 31 protruding from both end surfaces in the moving direction of the head 7.
43 are attached respectively. Therefore, the FPC43
Can be divided into two, and the divided FPCs 43 can be well isolated. The FPC 43 includes a signal line for transmitting a drive signal to the head 7 and a signal line for transmitting a signal from an optical sensor (not shown). In the present embodiment, these are equally divided into two. The total number of the tubes 31 is four, and ink of four colors is supplied. However, the distribution of the tubes 31 and the combination of the signal lines to the portions corresponding to the respective colors of the head 7 are basically free. However, if the distribution of the tubes 31 and the distribution of the signal lines of the FPC 43 are matched according to the ink color to be used, an advantage such as easy identification of the cause when a problem occurs can be considered. Are distributed as follows. Between the FPCs 43 thus divided, the F
Since the PCs 43 do not overlap each other, crosstalk does not occur. In addition, the F attached to each tube 31
Occurrence of crosstalk in the PC 43 can be satisfactorily prevented because the number of patterns is divided into two. Furthermore,
Each FPC 43 is connected to the tube 3 via the tube band 41.
Since it is attached to No. 1, its behavior can be stabilized like the tube 31.

Therefore, in the present embodiment, crosstalk can be prevented without increasing the size of the device.
That is, by maintaining the cross-sectional area of each FPC 43 small, it is possible to secure its flexibility and prevent crosstalk without using a large capacitor. Furthermore, the stable behavior of the FPC 43 as described above can improve its durability satisfactorily,
The load on the carriage motor 15 can also be reduced.
Therefore, this inkjet printer can form an extremely accurate image.

Moreover, in this embodiment, the FPC 43 and the protective film 45 are held so as to be movable in the longitudinal direction with respect to the tube band 41. Therefore, tube 3
Even if the tube 31 and the FPC 43 and the protective film 45 have different curvatures in the first curved portion, no twist occurs. Therefore, it is possible to further suppress the addition of the movement resistance to the head 7. Further, since the movement range of the protective film 45 is restricted by the cutout portion 45a, even if the FPC 43 and the protective film 45 move in the longitudinal direction as described above, they are easily returned to their original positions.

Since the tube band 41 immovably fixes the pair of tubes 31 to the pair of grooves 47, the occurrence of twists and the like can be better prevented by carrying out this fixing as follows. That is, the pair of tubes 31 may be fixed straight in parallel with a jig or the like, and the tube band 41 may be fixed to the fixed tubes 31. By doing so, the pair of tubes 31
It is possible to prevent the occurrence of a twist in the head and to further suppress the addition of the movement resistance to the head 7. Further, since the FPC 43 and the protective film 45 can be inserted into the groove 49 of the tube band 41 from above, they may be inserted at the end of the assembly.

Furthermore, since the protective film 45 has its width direction oriented perpendicular to the platen 5, the tube 31
Can be suppressed from bending in the recording paper direction. Therefore, in the present embodiment, it is possible to prevent the tube 31 from coming into contact with the recording medium and being contaminated, and to prevent the tube 3 from being damaged.
It is possible to make the bending behavior of 1 more smooth and to further suppress the addition of movement resistance from the tube 31 to the head 7. Therefore, the load on the carriage motor 15 can be reduced extremely well, the ink ejection position can be controlled more accurately, and thus a more accurate image can be formed.

The present invention is not limited to the above-described embodiments, and can be implemented in various forms without departing from the scope of the present invention. For example, by configuring the tube band 41 with a slightly hard plastic material having a slight elasticity, the rigidity of the retaining portion 60 can be increased, and the relative positions of the protective film 45, the FPC 43 and the tube 31 can be held more correctly. can do. Further, by making the diameter of the groove 47 of the tube band 41 smaller than the diameter of the tube 31, it is not necessary to form a slip stopper, so that the productivity of the tube band 41 is improved.

[Brief description of drawings]

FIG. 1 is a perspective view of an internal structure of an inkjet printer to which the present invention is applied, as viewed from a paper discharge side.

FIG. 2 is a perspective view of the internal structure viewed from the paper feed side.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a sectional view taken along line BB of FIG.

5 is an enlarged view of part C in FIG.

6A and 6B are a plan view, a side view, and a cross-sectional view taken along line D-D showing the configuration of the manifold of the inkjet printer.

FIG. 7 is an exploded perspective view showing configurations of a tube band, a tube, an FPC, and an FPC protective film of the inkjet printer.

FIG. 8 is a perspective view schematically showing how to fold the FPC.

[Explanation of symbols]

3 ... Conveyor roller 5 ... Platen 7
… Head 11… Carriage 13… Guide shaft 1
5 ... Carriage motor 19 ... Encoder strip 25 ... Cover 3
1 ... Tube 41 ... Tube band 43 ... FPC 4
5 ... FPC protective film 45a ... Notch portion 47, 49 ... Groove 5
1 ... Supporting part

Claims (6)

[Claims] 1. A head for ejecting ink to form an image on a recording medium, a tube for supplying ink to the head from an ink holding portion provided separately from the head, and the head for recording. An ink jet printer comprising: a head moving unit that reciprocates in the width direction of the medium, wherein the tubes project from both side end surfaces of the head in the moving direction, and the tubes project from both side end surfaces of the head to the head. An inkjet printer characterized in that a flat cable for energizing each is attached. 2. The ink jet printer according to claim 1, further comprising a binding member that binds and holds the tube and the flat cable. 3. The binding member holds either the tube or the flat cable movably in the longitudinal direction, and the binding position of the tube or the flat cable by the binding member can be displaced. The inkjet printer according to claim 2, characterized in that: 4. A protective film, which is attached to the tube and is formed in a strip shape with the width direction facing the recording medium, for suppressing the bending of the tube in the recording medium direction. The inkjet printer according to any one of claims 1 to 3, which is characterized in that. 5. The inkjet printer according to claim 4, wherein the protective film covers and protects the flat cable from a side opposite to the tube. 6. A bundling member for bundling and holding the protective film with the tube and the flat cable, wherein the bundling member moves either the flat cable, the protective film or the tube in a longitudinal direction. The ink jet printer according to claim 5, wherein the ink jet printer is held so that it can be held, and the binding position of the flat cable and the protective film or the tube can be displaced by the binding member.