JP6482111B2 - Cleaning device - Google Patents

Description

  The present invention relates to a cleaning device that cleans an object by spraying dry ice particles toward the object.

  This type of conventional cleaning apparatus is disclosed in, for example, Patent Document 1. The cleaning device disclosed in Patent Document 1 expands liquefied carbon dioxide in an expansion space in a nozzle body to generate dry ice particles, and introduces the generated dry ice particles into a flow of compressed air from an injection port. Spray toward the item to be cleaned. In this cleaning apparatus, there are an ejection hole provided at the center of the orifice pipe and a gas hole provided at the periphery of the ejection hole as the holes for ejecting liquefied carbon dioxide to the expansion space. The liquefied carbon dioxide ejected from the ejection hole passes through the triple point without being vaporized and becomes dry ice particles, and the liquefied carbon dioxide ejected from the gas hole suppresses the diffusion of the liquefied carbon dioxide ejected from the ejection hole. It is described that it works as a diffusion suppression film part.

JP 2011-167822 A

  However, in the cleaning apparatus disclosed in Patent Document 1, liquefied carbon dioxide ejected from a large number of gas holes provided at the periphery of the central ejection hole does not contribute to the cleaning action of the object to be cleaned. The detergency was not excellent for the consumption of liquefied carbon dioxide.

  Therefore, the inventors of the present application reviewed the structure of the ejection part that ejects liquefied carbon dioxide into the expansion space from the beginning, and as a result, succeeded in developing a cleaning device that has a much higher cleaning power than the conventional one. .

  Thus, an object of this invention is to provide the washing | cleaning apparatus excellent in the detergency.

The cleaning apparatus of the present invention includes a liquefied carbon dioxide supply path for supplying liquefied carbon dioxide, a carrier gas supply path for supplying carrier gas, and an ejection unit for ejecting liquefied carbon dioxide supplied from the liquefied carbon dioxide supply path. An expanded space in which liquefied carbon dioxide ejected from the ejection section expands to generate dry ice particles, a carrier gas supplied from the carrier gas supply path, and dry ice particles generated in the expanded space It is premised on a thing provided with the confluence | merging part to join and the injection path formed from the said confluence | merging part to the injection outlet. The jetting part jets liquefied carbon dioxide radially in a direction forming an acute angle with respect to an axial direction of the shaft part and a shaft part having a liquefied carbon dioxide passage connected to the liquefied carbon dioxide supply path inside. And a plurality of ejection passages (hereinafter referred to as “upstream ejection passages”) formed from the liquefied carbon dioxide passage to the expansion space, and radially in a direction forming an obtuse angle with respect to the axial direction of the shaft portion. And a plurality of ejection paths (hereinafter referred to as “downstream ejection paths”) formed from the liquefied carbon dioxide passage to the expansion space so as to eject liquefied carbon dioxide. The ejection direction of the upstream ejection path and the downstream ejection path so that the liquefied carbon dioxide ejected from the upstream ejection path and the liquefied carbon dioxide ejected from the downstream ejection path collide in the expansion space. And the spout position is set. The tip of the shaft is at a position away from the carrier gas supply path.

  According to the cleaning apparatus having such a configuration, the liquefied carbon dioxide ejected from the ejection portion into the expansion space expands while colliding with each other, and therefore, the cooling operation efficiently extends over a wide range of the expansion space. As a result, the amount of dry ice particles ejected from the ejection port increases, and the ejected dry ice particles become hard and can be expected to exhibit high detergency.

  The upstream jet passage and the downstream so that the liquefied carbon dioxide jetted from the upstream jet passage and the liquefied carbon dioxide jetted from the downstream jet passage collide in the expansion space and diffuse into a film shape. It is desirable that the ejection direction and the ejection position of the side ejection path are set.

  According to the cleaning device having such a configuration, the liquefied carbon dioxide ejected into the expansion space from the ejection portion collides with each other and expands while diffusing into a film shape, so that the expansion space is wider than the above-described cleaning device. It can be expected that the cooling action can be efficiently performed over a range and a higher detergency can be exhibited.

  The cleaning apparatus according to the present invention can be expected to exhibit higher cleaning power than the conventional cleaning apparatus.

It is the schematic which shows the example of whole structure of the washing | cleaning apparatus which concerns on embodiment of this invention. It is a fragmentary sectional view showing a cleaning gun in an embodiment of the invention. The portion of the two-dot chain line in the circle is shown in an enlarged view. It is an air piping system diagram in a control unit and a cleaning gun. It is a fragmentary sectional view which shows the cleaning apparatus (cleaning gun) of a comparison object. The portion of the two-dot chain line in the circle is shown in an enlarged view. It is a figure which shows the outline | summary of the measurement system for measuring the injection quantity and particle size of dry ice particle.

  Hereinafter, a cleaning apparatus according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the cleaning device 1 includes a cleaning gun 2, a control unit 3, a liquefied carbon dioxide cylinder 4, a water separator 6, a compressor 7, and the like. The compressor 7, the water separator 6, the control unit 3, and the cleaning gun 2 are connected via an air hose H. The liquefied carbon dioxide cylinder 4, the control unit 3, and the cleaning gun 2 are connected by a flexible hose F having a heat insulating function.

  As shown in FIG. 2, the cleaning gun 2 includes a cleaning gun body 8, a nozzle 9, a gripping part 11, an air injection trigger 12, a dry ice particle injection trigger 13, and the like. Further, the cleaning gun 2 is provided with a liquefied carbon dioxide supply path 14, an ejection part 16, an expansion space 17, a compressed air supply path 18 and a merging part 19. Hereinafter, each part will be described in detail.

  The liquefied carbon dioxide supply path 14 supplies liquefied carbon dioxide to the ejection section 16 and reaches the ejection section 16 from the liquefied carbon dioxide gas cylinder 4 via the internal flow path such as the control unit 3 and the flexible hose F. .

  The ejection unit 16 ejects liquefied carbon dioxide supplied from the liquefied carbon dioxide supply path 14 to the expansion space 17. The ejection portion 16 is the same as the joint portion 161 to which the end portion of the flexible hose F is connected, the male screw portion 162 screwed into one end opening of the substantially cylindrical body 21 attached to the cleaning gun body 8, and the male screw portion 162. And a shaft portion 163 that is formed on the core and extends in the longitudinal direction of the expansion space 17 (the direction toward the merge portion 19).

  A liquefied carbon dioxide passage 163 a connected to the liquefied carbon dioxide supply passage 16 is formed inside the shaft portion 163. The intermediate portion of the shaft portion 163 is formed with a small diameter portion 165 having a smaller diameter than the front and rear portions in the axial direction (hereinafter, this portion is also referred to as a “general portion 164”), and the general portion 164 and the small diameter portion 165 are formed. Between the two, truncated cone-shaped inclined portions 166 and 167 are formed.

  A plurality of ejection paths 168 (hereinafter referred to as “upstream ejection paths 168”) are formed from the liquefied carbon dioxide passage 163 a to the expansion space 17 in the inclined portion 166 formed on the proximal end side of the shaft portion 163. Yes. A plurality of ejection paths 169 (hereinafter referred to as “downstream ejection paths 169”) are also formed in the inclined portion 167 formed on the distal end side of the shaft portion 163 from the liquefied carbon dioxide passage 163 a to the expansion space 17. . The plurality of upstream ejection paths 168 are equally formed in the circumferential direction of the shaft portion 163, and have an acute angle (in this embodiment, with respect to the axial direction of the shaft portion 163 (the direction indicated by the arrow P in FIG. 2). 45 °) is formed so that liquefied carbon dioxide is ejected radially. In addition, the plurality of downstream ejection passages 169 are equally formed in the circumferential direction of the shaft portion 163, and are radially formed in a direction that forms an obtuse angle (135 ° in the present embodiment) with respect to the axial direction of the shaft portion 163. It is formed to eject liquefied carbon dioxide.

The liquefied carbon dioxide ejected from each upstream ejection path 168 and the liquefied carbon dioxide ejected from each downstream ejection path 169 collide with each other in the expansion space 17 and diffuse in the form of a film. And the spout position is set. In this embodiment, the number of the upstream ejection paths 168 and the number of the downstream ejection paths 169 are the same (each 8), and the circumferential positions around the shaft portion 163 of each upstream ejection path 168 and each downstream ejection The circumferential position around the shaft portion 163 of the path 169 is matched. Further, the ejection paths 168 and 169 are all formed in a direction perpendicular to the surfaces of the inclined portions 166 and 167.

  In the present embodiment, the expansion space 17 is formed of a substantially cylindrical cavity. In the expansion space 17, the liquefied carbon dioxide ejected from the upstream ejection passage 168 and the liquefied carbon dioxide ejected from the downstream ejection passage 169 collide with each other to form a film (for example, a film as indicated by a two-dot chain line Q in FIG. 2). Swells to form hard dry ice particles. However, although the shape Q of the film in FIG. 2 spreads in a direction perpendicular to the axial direction P of the shaft portion 163, the shape of the film is not limited to this, and the shape of the bowl 21 is substantially curved. Various other film shapes such as an incomplete film shape that does not reach the wall surface may be formed.

  The compressed air supply path 18 includes an internal compressed air supply path 18 a formed inside the cleaning gun 2 and an external compressed air supply path 18 b formed in the control unit 3 and the air hose F from the compressor 7. Yes.

  In the merge part 19, the air supplied from the compressed air supply path 18 and the dry ice particles generated in the expansion space 17 merge. An injection path 26 is formed in the nozzle 9 from the merging portion 19 to the injection port 24 at the tip of the nozzle 9 of the cleaning gun 2, and the dry ice particles that have merged with the air at the merging portion 19 are converted into an air flow. It is accelerated by riding and injected from the injection port 24 toward the object to be cleaned.

  The gripping part 11 supports the cleaning gun body 8, and the user operates the air injection trigger 12 and the dry ice particle injection trigger 13 while gripping the gripping part 11.

  As shown in FIG. 3, the control unit 3 is interposed in the middle of the external compressed air supply path 18 b and the liquefied carbon dioxide supply path 14. Specifically, pilot-type on-off valves 27 and 28 are provided in the middle positions of the external compressed air supply path 18b and the liquefied carbon dioxide supply path 14, respectively. Further, a branch pipe 29 is provided branching from a midway position of the external compressed air supply path 18b, and further branched into two hands after passing through the pressure reducing valve 31, and a compressed air branch pipe 32 and a liquefied carbon dioxide branch pipe. 33. Each branch pipe 32, 33 is connected to a pilot port of a pilot type on-off valve 27, 28. In addition, the compressed air branch pipe 32 is provided with a trigger interlocking valve 34 that opens and closes the flow path in conjunction with the air injection trigger 12, and the liquefied carbon dioxide branch pipe 33 is provided with dry ice. A trigger interlocking valve 36 that opens and closes the flow path in conjunction with the particle injection trigger 13 is provided. Thus, only when the air injection trigger 13 is pulled, the pilot on-off valve 27 provided in the external compressed air supply path 18 b is opened, and compressed air is supplied to the cleaning gun 2. Further, only when the trigger for spraying dry ice particles 13 is pulled, the pilot on-off valve 28 provided in the liquefied carbon dioxide supply path 14 is opened, and liquefied carbon dioxide is in the expansion space 17 in the cleaning gun 2. Supplied.

In the cleaning apparatus 1 having the above configuration, when the triggers 12 and 13 are pulled, the liquefied carbon dioxide is fed from the liquefied carbon dioxide cylinder 4 into the ejection section 16 through the flexible hose F and the like at a predetermined pressure. The liquefied carbon dioxide is ejected into the expansion space 17 from the upstream ejection path 168 and the downstream ejection path 169 of the portion 16. At this time, as described above, the liquefied carbon dioxide ejected from the upstream ejection path 168 and the liquefied carbon dioxide ejected from the downstream ejection path 169 collide with each other and expand while diffusing into a film shape, thereby forming hard dry ice. Form particles. The dry ice particles formed in this way are mixed in the air that flows linearly from the compressed air supply path 18 toward the injection path 26 at the junction 19, and are accelerated in the injection path 26 by riding on the air flow. Thereafter, the fuel is ejected from the ejection port 24 toward the object to be cleaned. The sprayed dry ice particles collide with the surface of the object to be cleaned and clean the surface of the object to be cleaned.

  By the way, about the dry ice particle sprayed by the said washing | cleaning apparatus 1, the particle number of the dry ice particle sprayed within the predetermined time and the average particle diameter were measured. This measurement was performed using a measurement system as shown in FIG. This measurement system mainly includes a YAG laser device 61, a PIV camera 62, and an image analysis device (not shown). The irradiation direction of the pulsed laser light from the YAG laser device 61 and the light receiving part of the PIV camera 62 are opposed to each other, and the dry ice particles 63 ejected from the cleaning device 1 between them are perpendicular to the facing direction. Passed through. The pulsed laser beam oscillated by the YAG laser device 61 was set so as to hit against dry ice particles passing through a position 150 mm away from the injection port 24. The pulse width of the pulse laser beam was 8 ns, the repetition period was 20 Hz, and the beam diameter was 4 mm. Further, the shadow of dry ice particles that appeared when the pulsed laser beam was turned on was imaged by the PIV camera 62. For each measurement, imaging with the PIV camera 62 was performed for 10 seconds with a period of 0.1 second, and a total of 100 images were acquired. Based on the size and number of shadows of the dry ice particles in the predetermined range (rectangular range of about 2.4 mm × 3.0 mm) of the image captured by the PIV camera 62, the image analysis apparatus converts the image into 100 images. The number of captured dry ice particles and the average particle size of the dry ice particles are calculated.

  In addition, as a comparative example, the above measurement was performed for a cleaning device 51 (cleaning gun 52) as shown in FIG. The cleaning device 51 to be compared is the same as the cleaning device 1 described above, except that the ejection portion 16 (see FIG. 2) is replaced with the ejection portion 53 as shown in FIG. The same. The ejection unit 53 of the cleaning device 51 to be compared ejects liquefied carbon dioxide supplied from the liquefied carbon dioxide supply path 14 from one ejection hole 53 a in the longitudinal direction of the expansion space 17. The liquefied carbon dioxide ejected on the water expands into dry ice particles. Of course, if this ejection part 53 is used, collision of liquefied carbon dioxide in the expansion space 17 and formation of a film will not be performed.

  Details of each part of the cleaning apparatus 1 applied in this measurement are shown below. The inner diameter D of the expansion space 17 is 22 mm. The inner diameter D2 of the internal compressed air supply path 18a is 30 mm. The merging angle at the merging portion 19 is 30 °. The distance L from the collision position of the liquefied carbon dioxide to the center of the merging portion 19 is about 145 mm. The inner diameter D3 of the injection port 24 is 14 mm. The inner diameters of the ejection channels 168 and 169 are 0.4 mm. The original pressure of the compressed air is 0.65 MPa (measured between the water separator 6 and the control unit 3). The flow rate of the compressed air is 5000 L / min (measured between the water separator 6 and the control unit 3). The original pressure of liquefied carbon dioxide is 2.0 MPa. The injection distance from the tip of the nozzle 9 to the measurement position is 150 mm.

  On the other hand, for details of each part of the cleaning device 51 to be compared, the distance L from the position where the liquefied carbon dioxide is injected into the expansion space 17 to the center of the merging portion 19 is about 145 mm, and the inner diameter of the injection hole 53a is 1. It was set to 4 mm or 1.6 mm. Note that the inner diameter D of the expansion space 17, the inner diameter D2 of the internal compressed air supply path 18a, the merging angle at the merging portion 19, the inner diameter D3 of the injection port 24, the original pressure of the compressed air, the flow rate of the compressed air, the original pressure of the liquefied carbon dioxide The spraying distance from the tip of the nozzle 9 to the measurement position was the same as that of the cleaning device 1.

  The total area of the ejection paths 168 and 169 in the ejection part 16 of the cleaning apparatus 1 and the area of the ejection hole 35a of the ejection part 53 of the cleaning apparatus 51 to be compared (particularly, the inner diameter of the ejection hole 53a is 1.6 mm) The carbon dioxide consumption rate is almost the same.

The result of the measurement carried out under the above conditions is shown below.
First, for the cleaning device 1, the number of dry ice particles sprayed within a predetermined time (the number of dry ice particles reflected in the 100 images; the same applies hereinafter) is 1496. The average particle size of the particles (the average particle size of the dry ice particles shown in the 100 images; the same applies hereinafter) was 139.5 μm.
On the other hand, for the cleaning device 51 to be compared (with the inner diameter of the ejection hole 53a of 1.4 mm), the number of dry ice particles injected within a predetermined time is 369, and the average of these dry ice particles The particle size was 163.7 μm.
For the cleaning device 51 to be compared (with the ejection hole 53a having an inner diameter of 1.6 mm), the number of dry ice particles injected within a predetermined time is 393, and the average particle size of these dry ice particles is 130. .4 μm.

  Based on the above measurement results, when the cleaning device 1 according to the embodiment of the present invention is compared with the cleaning device 51 to be compared, there is not much difference in the particle size of the dry ice particles. However, with regard to the number of dry ice particles, it can be said that the cleaning apparatus 1 according to the embodiment of the present invention has much more (3.8 times to 4 times). In other words, it can be said that the cleaning apparatus 1 according to the embodiment of the present invention ejects a much larger amount of dry ice particles.

  As described above, the amount of the dry ice particles to be ejected increases because the liquefied carbon dioxide ejected from the ejection section 16 collides with each other and expands while diffusing into a film shape. Cooling action efficiently over the range (a wide range in the expansion space 17 is set to −56 ° C. or less). As a result, the solidification rate of the liquefied carbon dioxide ejected from the ejection portion 16 into the expansion space 17 is high. This is considered to be because. Moreover, it is thought that the dry ice particles produced | generated become harder because a cooling effect reaches | attains efficiently over the wide range in the expansion space 17. FIG. That is, according to the cleaning apparatus 1 according to the embodiment of the present invention, the number of times the dry ice particles collide against the object to be cleaned is remarkably increased, and the hardness of the dry ice particles becomes relatively hard. It can be expected to demonstrate high detergency.

Q membrane 1 cleaning equipment
2 Cleaning gun
8 Cleaning gun body 9 Nozzle
DESCRIPTION OF SYMBOLS 11 Grip part 14 Liquefied carbon dioxide supply path 16 Ejection part 17 Expansion space 18 Compressed air supply path (carrier gas supply path)
19 Junction part 24 Injection port 26 Injection path 163 Shaft part 163a Liquefaction carbon dioxide path 168 Upstream side ejection path 169 Downstream side ejection path

Claims (4)

A liquefied carbon dioxide supply path for supplying liquefied carbon dioxide;
A carrier gas supply path for supplying carrier gas;
An ejection part for ejecting liquefied carbon dioxide supplied from the liquefied carbon dioxide supply path;
Expansion space in which liquefied carbon dioxide ejected from the ejection part expands to generate dry ice particles;
A merging section for merging the carrier gas supplied from the carrier gas supply path and the dry ice particles generated in the expansion space;
An injection path formed from the junction to the injection port;
In a cleaning apparatus comprising:
The ejection part is
A shaft portion having a liquefied carbon dioxide passage connected to the liquefied carbon dioxide supply passage inside,
A plurality of jet passages (hereinafter referred to as “upstream jets”) formed from the liquefied carbon dioxide passage to the expansion space so as to jet liquefied carbon dioxide radially in a direction that forms an acute angle with respect to the axial direction of the shaft portion. Road ”)
A plurality of jet passages (hereinafter referred to as “downstream jets” formed from the liquefied carbon dioxide passage to the expansion space so as to jet liquefied carbon dioxide radially in a direction that forms an obtuse angle with respect to the axial direction of the shaft portion. Road ”)
Have
The ejection direction of the upstream ejection path and the downstream ejection path so that the liquefied carbon dioxide ejected from the upstream ejection path and the liquefied carbon dioxide ejected from the downstream ejection path collide in the expansion space. And the spout position is set ,
The cleaning device according to claim 1, wherein a tip portion of the shaft portion is located away from the carrier gas supply path . The cleaning device according to claim 1,
The upstream jet passage and the downstream so that the liquefied carbon dioxide jetted from the upstream jet passage and the liquefied carbon dioxide jetted from the downstream jet passage collide in the expansion space and diffuse into a film shape. A cleaning apparatus, characterized in that an ejection direction and an ejection position of a side ejection path are set. The cleaning apparatus according to claim 1 or 2,
A cleaning apparatus, wherein a flow path from the carrier gas supply path to the injection port is formed so that the carrier gas is accelerated downstream from the merging portion. A cleaning gun having a cleaning gun body having the carrier gas supply path and the expansion space formed therein, a nozzle having the injection path formed therein, and a gripping portion for supporting the cleaning gun body. The cleaning apparatus according to any one of claims 1 to 3, comprising:
The cleaning apparatus, wherein the expansion space and the grip portion are formed on opposite sides as viewed from the longitudinal direction of the carrier gas supply path.

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