JP2022061177A - Dry ice-snow cleaning device - Google Patents

Abstract

To spray dry ice-snow widely and strongly.SOLUTION: A mixing part 150 mixes a carbon dioxide gas 10 containing liquefied carbonic acid that has passed a throttle part 120 and an injection gas 20 to generate a mixed gas 30. A nozzle 160 is connected to the mixing part 150, and injects the mixed gas 30. The nozzle 160 includes a large diameter part 170, a diameter reduction part 180 and a slit part 190 in this order. The large diameter part 170 has a first inner peripheral surface 171 which is connected to the mixing part 150, and has a constant inner diameter 171D. The diameter reduction part 180 has a second inner peripheral surface 181 which is connected to the large diameter part 170, and a diameter of which is reduced as separating from the large diameter part 170. The slit part 190 is provided from a tip of the nozzle 160 to a position continuous with the second inner peripheral surface 181 in an axial direction of the nozzle 160 while extending in a direction orthogonal to the axial direction of the nozzle 160 and penetrating the nozzle 160. A space inside the slit part 190 communicates with a space inside the second inner peripheral surface 181.SELECTED DRAWING: Figure 3

Description

The present invention relates to a dry ice snow cleaning device.

As prior documents disclosing the configuration of the dry ice snow cleaning device, there are Japanese Patent Application Laid-Open No. 2016-101625 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2001-179634 (Patent Document 2).

The dry ice snow cleaning device described in Patent Document 1 includes a liquefied carbon dioxide gas supply system, an injection gas supply system, a throttle portion, a mixing portion, and a nozzle. The liquefied carbon dioxide gas supplied from the liquefied carbon dioxide gas supply system becomes carbon dioxide gas containing dry ice snow generated by passing through the throttle portion. In the mixing section, the carbon dioxide gas containing dry ice snow and the injection gas supplied from the injection gas supply system are mixed to form a mixed gas. The mixed gas is injected from the injection port of the nozzle connected to the mixing portion.

The cleaning dry ice snow injection device described in Patent Document 2 includes an inner tube, an outer cylinder, and a dry ice snow injection nozzle. Liquefied carbon dioxide gas flows through the inner pipe. The outer cylinder surrounds the inner pipe. The injected gas flows between the outer cylinder and the inner pipe and is ejected from the injection gas injection port. The dry ice snow injection nozzle has a throttle portion in the vicinity of the connection side with the inner pipe and is connected to the inner pipe, and has a tapered shape extending toward the injection port having a flat tip. The dry ice snow generated by the liquefied carbon dioxide gas passing through the throttle portion is injected from the injection port in a wide angle with a constant injection width.

Japanese Unexamined Patent Publication No. 2016-101625 Japanese Unexamined Patent Publication No. 2001-179634

In Patent Document 1, there is room for spraying dry ice snow at a wide angle.

In Patent Document 2, the injection gas is injected separately from the dry ice snow from the injection gas injection port located on the outer periphery of the dry ice snow injection nozzle, and the injection speed of the dry ice snow is increased by the injection of the injection gas. It is difficult to spray dry ice snow strongly because it hardly rises.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a dry ice snow cleaning device capable of strongly spraying dry ice snow over a wide angle.

The dry ice snow cleaning device based on the present invention includes a liquefied carbon dioxide gas supply system, an injection gas supply system, a throttle portion, a mixing portion, and a nozzle. The liquefied carbon dioxide gas supply system supplies liquefied carbon dioxide gas. The injection gas supply system supplies the injection gas. The throttle portion is provided on the downstream side of the liquefied carbon dioxide gas supply system. The mixing section connects the liquefied carbon dioxide gas supply system and the injection gas supply system, and mixes the carbon dioxide gas containing liquefied carbon dioxide that has passed through the throttle section with the injection gas to generate a mixed gas. The nozzle is connected to the mixing section and injects the mixed gas. The nozzle includes a large diameter portion, a reduced diameter portion, and a slit portion in this order toward the axial tip of the nozzle. The large diameter portion has a first inner peripheral surface that is connected to the mixing portion and has a constant inner diameter. The reduced diameter portion has a second inner peripheral surface which is connected to the large diameter portion and whose diameter is reduced as the distance from the large diameter portion increases in the axial direction. The slit portion extends in a direction orthogonal to the axial direction and penetrates the nozzle, and is provided from the tip of the nozzle in the axial direction to a position continuous with the second inner peripheral surface. The space inside the slit portion communicates with the space inside the second inner peripheral surface.

In one embodiment of the present invention, the length from the mixing portion to the tip of the nozzle in the axial direction is 0.09 times or more 0.8 with respect to the length from the throttle portion to the tip of the nozzle in the axial direction. It is less than double.

In one embodiment of the present invention, the pressure of the injection gas in the injection gas supply system is 0.6 MPa or more and 0.9 MPa or less.

In one embodiment of the present invention, the length from the mixing portion to the tip of the nozzle in the axial direction is 20 mm or more and 141 mm or less.

According to the present invention, dry ice snow can be strongly sprayed over a wide angle.

It is a schematic diagram which shows the structure of the dry ice snow washing apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the structure of the liquefied carbon dioxide gas supply system, the mixing part and the nozzle provided in the dry ice snow cleaning apparatus which concerns on one Embodiment of this invention. FIG. 2 is a cross-sectional view of the liquefied carbon dioxide gas supply system, the mixing portion, and the nozzle of FIG. 2 as viewed from the direction of the arrow along line III-III. FIG. 2 is a cross-sectional view of the liquefied carbon dioxide gas supply system, the mixing portion, and the nozzle of FIG. 2 as viewed from the direction of the arrow along the IV-IV line. It is sectional drawing which shows the state which the dry ice snow is generated by enlarging the V part of FIG. FIG. 3 is a cross-sectional view showing a state in which dry ice snow is generated when viewed from a direction orthogonal to the extending direction of the slit portion in the dry ice snow cleaning device according to the embodiment of the present invention. It is sectional drawing which shows the nozzle of the dry ice snow washing apparatus which concerns on the modification of one Embodiment of this invention.

Hereinafter, the dry ice snow cleaning device according to the embodiment of the present invention will be described with reference to the drawings. In the following description of the embodiment, the same or corresponding parts in the drawings are designated by the same reference numerals, and the description thereof will not be repeated.

FIG. 1 is a schematic diagram showing a configuration of a dry ice snow cleaning device according to an embodiment of the present invention. FIG. 2 is a perspective view showing the configuration of a liquefied carbon dioxide gas supply system, a mixing unit, and a nozzle included in the dry ice snow cleaning device according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of the liquefied carbon dioxide gas supply system, the mixing portion, and the nozzle of FIG. 2 as viewed from the direction of the arrow along line III-III. FIG. 4 is a cross-sectional view of the liquefied carbon dioxide gas supply system, the mixing portion, and the nozzle of FIG. 2 as viewed from the direction of the arrow along the IV-IV line.

In the following description, the axial direction of the nozzle is the X-axis direction, the direction orthogonal to the axial direction of the nozzle and parallel to the extending direction of the slit portion is orthogonal to the Y-axis direction, the axial direction of the nozzle and the extending direction of the slit portion. The direction to be used is the Z-axis direction. In FIG. 4, the nozzle is enlarged and shown.

As shown in FIGS. 1 to 4, the dry ice snow cleaning device 1 according to the present embodiment includes a liquefied carbon dioxide gas supply system for supplying liquefied carbon dioxide gas, an injection gas supply system for supplying injection gas, and an injection gas supply system. A mixing unit 150 and a nozzle 160 are provided.

As shown in FIG. 1, the liquefied carbon dioxide gas supply system includes a liquefied carbon dioxide gas storage container 100, a carbon dioxide gas pipe 101, a first opening / closing portion 110, and a throttle portion 120. The liquefied carbon dioxide gas supply system further includes a pressure gauge for measuring the pressure inside the carbon dioxide gas pipe 101, and a filter provided on the downstream side of the pressure gauge to remove impurities in the liquefied carbon dioxide gas.

The liquefied carbon dioxide gas storage container 100 stores liquefied carbon dioxide gas. The carbon dioxide gas pipe 101 is connected to the liquefied carbon dioxide gas storage container 100 to form a flow path for the liquefied carbon dioxide gas or the carbon dioxide gas.

The first opening / closing portion 110 is provided in the middle of the carbon dioxide gas pipe 101. The first opening / closing unit 110 is composed of a valve that can be opened / closed manually. The first opening / closing unit 110 may be configured by a valve that can be automatically opened / closed.

As shown in FIGS. 1 to 3, the throttle portion 120 is provided on the downstream side of the first opening / closing portion 110 in the liquefied carbon dioxide gas supply system. In one embodiment of the present invention, the throttle portion 120 is composed of an orifice plate. The flow rate of the liquefied carbon dioxide gas 10L is adjusted by the throttle unit 120. The throttle portion 120 is not limited to the configuration of the orifice plate, and may be configured by, for example, a needle valve or the like.

As shown in FIG. 3, the inner diameter 120D of the throttle portion 120 in one embodiment of the present invention is, for example, 0.3 mm or more and 0.7 mm or less. The inner diameter 120D can be adjusted by changing the orifice plate. When increasing the particle size of dry ice snow, which will be described later, it is preferable that the inner diameter 120D is large. However, if the inner diameter 120D is made too large, the consumption of 10 L of liquefied carbon dioxide gas increases. It is preferable to set the inner diameter 120D in consideration of both the consumption of 10 L of gas.

As shown in FIG. 1, the injection gas supply system includes an injection gas supply source 130, an injection gas pipe 131, and a second opening / closing portion 140. The injection gas supply system further includes a pressure gauge for measuring the pressure inside the injection gas pipe 131, and a filter provided on the downstream side of the pressure gauge to remove impurities in the injection gas.

The injection gas supply source 130 supplies the injection gas. The injection gas pipe 131 is connected to the injection gas supply source 130 to form a flow path for the injection gas.

The injection gas supply source 130 or the injection gas pipe 131 is heated by a heater such as a heater as needed. By heating the injection gas supply source 130 or the injection gas pipe 131, the temperature of the injection gas can be adjusted so that the cleaning effect is enhanced according to the type and state of dirt on the object to be cleaned, and the object to be cleaned is dewed. Can be suppressed.

The second opening / closing portion 140 is provided in the middle of the injection gas pipe 131, and is composed of a valve that can be manually opened / closed. The second opening / closing unit 140 may be composed of a valve that can be automatically opened / closed. The injection gas is a gas that is inert to the carbon dioxide gas, such as dry air, nitrogen gas, argon gas, or carbon dioxide gas.

As shown in FIGS. 1 to 3, the mixing unit 150 connects the liquefied carbon dioxide gas supply system and the injection gas supply system, and the carbon dioxide gas 10 containing liquefied carbon dioxide and the injection gas 20 that have passed through the throttle unit 120. Is mixed to generate a mixed gas 30. Specifically, the mixing section pipe 151 constituting the mixing section 150 is airtightly connected to each of the tip of the carbon dioxide gas pipe 101, the tip of the injection gas pipe 131, and the rear end of the nozzle 160. The mixed gas 30 is in a gas-liquid mixed phase state in which the carbon dioxide gas 10 containing liquefied carbonic acid and the injection gas 20 are mixed.

As shown in FIGS. 2 and 3, in the mixing section pipe 151, two cylindrical pipes are connected at right angles to each other in a T-shape. The virtual central axes of the two cylindrical tubes of the mixing section pipe 151 are orthogonal to each other at the mixing section reference position 150d. In the mixing unit 150 according to the embodiment of the present invention, the two cylindrical tubes are orthogonal to each other, but the present invention is not limited to this, and the two cylindrical tubes may intersect each other diagonally.

The inner peripheral surface on one side of the mixing portion pipe 151 in the X-axis direction is continuous with the first inner peripheral surface on the rear end side of the nozzle 160. That is, the inner diameter of the mixing portion pipe 151 on the tip end side is substantially the same as the inner diameter of the large diameter portion 170 of the nozzle 160, which will be described later.

As shown in FIGS. 2 to 4, the nozzle 160 has a tapered outer shape on one side in the X-axis direction. The nozzle 160 is connected to the mixing unit 150 and injects a mixed gas 30 of a carbon dioxide gas 10 containing liquefied carbon dioxide and an injection gas 20. The nozzle 160 includes a large diameter portion 170, a reduced diameter portion 180, and a slit portion 190 in this order toward the tip of the nozzle 160 in the axial direction (X-axis direction).

As shown in FIGS. 3 and 4, the large diameter portion 170 has a first inner peripheral surface 171 that is connected to the mixing portion 150 and has a constant inner diameter. The first inner peripheral surface 171 in the present embodiment has a constant inner diameter 171D along the X-axis direction continuous with the inner peripheral surface of the mixing portion pipe 151. The inner diameter 171D of the large diameter portion 170 in one embodiment of the present invention is, for example, 15 mm.

The reduced diameter portion 180 includes a second inner peripheral surface 181 and an opening portion 182. The second inner peripheral surface 181 is connected to the large diameter portion 170, and the diameter is reduced as it is separated from the large diameter portion 170 in the axial direction (X-axis direction) of the nozzle 160. The second inner peripheral surface 181 has a conical surface shape. The second inner peripheral surface 181 in the present embodiment is continuous with the first inner peripheral surface 171 on the other end side in the X-axis direction.

The opening 182 is connected to one end side of the second inner peripheral surface 181 in the X-axis direction. The opening 182 has a vertical width of 182 W in the Z-axis direction and a horizontal width of 182 L in the Y-axis direction. The vertical width of 182 W is, for example, 0.5 mm or more and 0.9 mm or less, and more preferably 0.6 mm or more and 0.8 mm or less. The width 182L is, for example, 2 mm or more and 20 mm or less, and more preferably 10 mm or more and 15 mm or less. The width of 182L is preferably 10 times or more and 40 times or less of the height of 182W.

The slit portion 190 extends in a direction orthogonal to the axial direction of the nozzle 160 (Y-axis direction) and penetrates the nozzle 160, while the diameter-reduced portion from the tip of the nozzle 160 in the axial direction (X-axis direction) of the nozzle 160. It is provided up to a position continuous with the second inner peripheral surface 181 of 180. Specifically, the opening 182 is located at the boundary between the slit 190 and the second inner peripheral surface 181. The slit portion 190 is separated from the large diameter portion 170. That is, the slit portion 190 is not continuous with the first inner peripheral surface 171 of the large diameter portion 170.

The space inside the slit portion 190 communicates with the space inside the second inner peripheral surface 181. That is, the space inside the slit portion 190 communicates with the space inside the second inner peripheral surface 181 through the opening 182. As a result, the mixed gas 30 flows through the large diameter portion 170, the reduced diameter portion 180, and the slit portion 190 in this order.

The slit portion 190 includes a front injection port 191 and a side injection port 192. The front injection port 191 is provided at the tip of the nozzle 160 on one end side in the X-axis direction. The front injection port 191 has a vertical width of 191 W in the Z-axis direction and a horizontal width of 191 L in the Y-axis direction. The vertical width of 191 W is, for example, 0.5 mm or more and 0.9 mm or less, and more preferably 0.6 mm or more and 0.8 mm or less. The width 191L is, for example, 20.0 mm or more and 21.0 mm or less, and more preferably 20.5 mm or more and 20.9 mm or less. The vertical width 191W is preferably the same as the vertical width 182W of the opening 182.

As shown in FIGS. 2 and 4, side injection ports 192 are provided at both ends of the slit portion 190 in the Y-axis direction. The side injection port 192 has a vertical width of 192 W in the Z-axis direction and a horizontal width of 192 L in the Y-axis direction.

As shown in FIG. 2, the vertical width 192 W is, for example, 0.5 mm or more and 0.9 mm or less, and more preferably 0.6 mm or more and 0.8 mm or less. The vertical width 192W is preferably the same as the vertical widths 182W and 191W.

As shown in FIG. 4, the width 192L is, for example, 4.00 mm or more and 10.35 mm or less, and more preferably 6.0 mm or more and 6.5 mm or less. The width 182L of the opening 182 varies according to the dimension of the width 192L of the side injection port 192. That is, the width 182L becomes wider as the width 192L becomes wider, and becomes narrower as the width 192L becomes narrower.

The dry ice snow radially ejected from the opening 182 is ejected from the front injection port 191 and the side injection port 192 toward the X-axis direction while spreading in the Y-axis direction.

As shown in FIG. 3, the length from the mixing portion 150 to the tip of the nozzle 160 in the axial direction (X-axis direction) of the nozzle 160 is the length of the nozzle 160 in the axial direction (X-axis direction) of the nozzle 160 from the throttle portion 120. It is 0.09 times or more and 0.8 times or less with respect to the length to the tip. Specifically, the length L1 from the mixing portion reference position 150d in the X-axis direction to the front injection port 191 is 0 with respect to the length L2 from the center of the throttle portion 120 in the X-axis direction to the front injection port 191. .09 times or more and 0.8 times or less.

In one embodiment of the present invention, the length from the mixing unit 150 to the tip of the nozzle 160 in the axial direction (X-axis direction) of the nozzle 160 is 20 mm or more and 141 mm or less. Specifically, the length L1 from the mixing portion reference position 150d to the front injection port 191 in the X-axis direction is 20 mm or more and 141 mm or less.

The dry ice snow cleaning device 1 can increase the cleaning processing capacity by increasing the number of particles of dry ice snow generated. In order to increase the number of particles of dry ice snow, it is necessary to shorten the length of the nozzle 160 to reduce the heat input to the mixed gas 30 from the outside and suppress the vaporization of the liquefied carbon dioxide contained in the mixed gas 30. You will need it. As shown in the present embodiment, the length L1 from the mixing unit reference position 150d to the front injection port 191 in the X-axis direction is used as a ratio to the length L2 from the throttle portion 120 to the front injection port 191 in the X-axis direction. By defining or quantitatively defining the length L1 from the mixing unit reference position 150d to the front injection port 191 in the X-axis direction, the heat input to the mixed gas 30 from the outside is reduced, so that the nozzle 160 Since it is possible to suppress the vaporization of the liquefied carbon dioxide contained in the mixed gas 30 inside, it is possible to facilitate the generation of dry ice snow from the mixed gas 30 introduced up to the slit portion 190.

Hereinafter, the operation of the dry ice snow cleaning device 1 according to the embodiment of the present invention will be described.

First, as shown in FIGS. 1 and 3, in the liquefied carbon dioxide gas supply system, 10 L of liquefied carbon dioxide gas is flowed from the liquefied carbon dioxide gas storage container 100 into the liquefied carbon dioxide gas pipe 101. The liquefied carbon dioxide gas pressure in the liquefied carbon dioxide gas pipe 101 is measured by a pressure gauge provided in the carbon dioxide gas pipe 101. The pressure of 10 L of liquefied carbon dioxide gas is, for example, 6.2 MPa or more and 7.6 MPa or less. The pressure of 10 L of liquefied carbon dioxide gas in one embodiment of the present invention is 7.0 MPa.

Next, the first opening / closing portion 110 is opened, and the liquefied carbon dioxide gas 10L in the liquefied carbon dioxide gas pipe 101 passes through the throttle portion 120. When the liquefied carbon dioxide gas 10L passes through the drawing section 120, the liquefied carbon dioxide gas 10L that has passed through the drawing section 120 is equalized with the pressure inside the mixing section 150 and the nozzle 160. As a result, the temperature of the liquefied carbon dioxide gas 10L drops to about −49 ° C. due to adiabatic expansion, and becomes the carbon dioxide gas 10 containing liquefied carbon dioxide. The carbon dioxide gas 10 containing liquefied carbonic acid flows into the mixing portion 150.

In the injection gas supply system, the injection gas 20 is made to flow into the injection gas pipe 131 from the injection gas supply source 130. The pressure of the injection gas in the injection gas pipe 131 is measured by the pressure gauge provided in the injection gas pipe 131. Next, the second opening / closing portion 140 is opened, and the injection gas in the injection gas pipe 131 flows into the inside of the mixing portion 150. The pressure of the injection gas 20 in the injection gas supply system is 0.6 MPa or more and 0.9 MPa or less. The pressure of the injection gas 20 is adjusted by the second opening / closing unit 140.

In the mixing unit 150, the carbon dioxide gas 10 and the injection gas 20 are mixed to generate the mixed gas 30. The mixed gas 30 generated in the mixing unit 150 flows into the inside of the large diameter portion 170 of the nozzle 160. The pressure of the mixed gas 30 is dominated by the pressure of the injection gas 20 as compared with the carbon dioxide gas 10, and fluctuates following the pressure of the injection gas 20.

FIG. 5 is a cross-sectional view showing a state in which the V portion of FIG. 3 is enlarged to generate dry ice snow. FIG. 6 is a cross-sectional view showing a state in which dry ice snow is generated when viewed from a direction orthogonal to the extending direction of the slit portion in the dry ice snow cleaning device according to the embodiment of the present invention. In FIG. 6, it is shown in the same cross-sectional view as in FIG.

As shown in FIGS. 5 and 6, the mixed gas 30 that has flowed into the large diameter portion 170 of the nozzle 160 flows into the reduced diameter portion 180. The mixed gas 30 is accelerated when passing through the reduced diameter portion 180, and its flow velocity becomes the speed of sound when passing through the opening 182. Inside the slit portion 190, the pressure of the mixed gas 30 becomes low while the pressure drops from the pressure inside the nozzle 160. As a result, the dry ice snow 31 is generated inside the slit portion 190.

The position where the dry ice snow 31 is generated in the X-axis direction is displaced by the size of the cross-sectional area of the opening 182 in the YZ plane. The pressure of the mixed gas 30 inside the nozzle 160 changes depending on the size of the cross-sectional area of the opening 182. When the cross-sectional area of the opening 182 becomes large, the pressure of the mixed gas 30 inside the nozzle 160 decreases. Therefore, the pressure of the mixed gas 30 may drop to the pressure generated inside the nozzle 160 by the dry ice snow 31. In this case, the dry ice snow 31 may be generated inside the large diameter portion 170 and the reduced diameter portion 180, and the dry ice snow 31 may be clogged at the opening 182.

In order to prevent the dry ice snow 31 from being generated inside the large diameter portion 170 and the reduced diameter portion 180 as described above, the pressure of the injection gas 20 and the size of the cross-sectional area of the opening 182 in the YZ plane are adjusted. Will be done. The cross-sectional area of the opening 182 in the YZ plane is determined by the vertical width 182W and the horizontal width 182L.

The mixed gas 30 including the dry ice snow 31 is further accelerated in the slit portion 190, and the flow velocity becomes supersonic when injected from the front injection port 191. The mixed gas 30 including the dry ice snow 31 flows in the X-axis direction while radially spreading in the Y-axis direction along the inner shape of the slit portion 190.

The mixed gas 30 containing the dry ice snow 31 injected from the slit portion 190 becomes low in temperature while the pressure decreases, and the particles of the dry ice snow 31 grow even larger. The mixed gas 30 containing the greatly grown dry ice snow 31 is injected at a wide angle while spreading radially in the Y-axis direction.

When the distance from the front injection port 191 to the object to be cleaned is 20 mm, the width in the Y-axis direction in which the object to be cleaned by the dry ice snow cleaning device 1 according to the embodiment of the present invention is 20 mm or more and 45 mm or less. Is. The maximum collision pressure of the mixed gas 30 including the dry ice snow 31 with respect to the object to be cleaned is 30 MPa or more and 40 MPa or less, and it is sufficient that the maximum collision pressure of at least 30 MPa or more is secured. In this way, by strongly spraying the dry ice snow 31 on the object to be cleaned at a wide angle in the Y-axis direction, it is possible to strongly wash a wide range of the object to be cleaned at one time.

In the dry ice snow cleaning device 1 according to the embodiment of the present invention, the slit portion 190 extends in a direction orthogonal to the axial direction of the nozzle 160 and penetrates the nozzle 160 in the axial direction of the nozzle 160. It is provided from the tip of the nozzle 160 until it is continuous with the second inner peripheral surface 181 of the reduced diameter portion 180. As a result, the mixed gas 30 in which the carbon dioxide gas 10 and the injection gas 20 are mixed and flow into the slit portion 190 accelerates inside the reduced diameter portion 180, and the dry ice snow 31 is generated inside the slit portion 190. The dry ice snow 31 is provided because the particles of the dry ice snow 31 can be greatly grown inside the slit portion 190 and in the vicinity of the front injection port 191 while spreading and flowing radially in the direction orthogonal to the axial direction of the nozzle 160. It can be sprayed strongly on a wide angle.

In the dry ice snow cleaning device 1 according to the embodiment of the present invention, the length from the mixing section reference position 150d to the front injection port 191 in the X-axis direction is set to the length from the throttle section 120 to the front injection port 191 in the X-axis direction. By 0.09 times or more and 0.8 times or less with respect to the nozzle length, the heat input from the outside to the mixed gas 30 is reduced and the temperature rise of the mixed gas 30 inside the nozzle 190 is suppressed. Therefore, the dry ice snow 31 can be easily generated from the mixed gas 30 introduced up to the slit portion 190, and the cleaning ability can be improved.

In the dry ice snow cleaning device 1 according to the embodiment of the present invention, the pressure of the mixed gas 30 inside the nozzle 160 is set to 0 by setting the pressure of the injection gas 20 to 0.6 MPa or more and 0.9 MPa or less. Since the position where the dry ice snow 31 is generated in the X-axis direction can be set inside the slit portion 190 while maintaining the pressure at 6.6 MPa or more and 0.9 MPa or less, the dry ice snow 31 is clogged at the opening 182. It is possible to suppress and stably inject the dry ice snow 31.

In the dry ice / snow cleaning device 1 according to the embodiment of the present invention, the length from the mixing unit reference position 150d to the front injection port 191 in the X-axis direction is defined as 20 mm or more and 141 mm or less, whereby the mixed gas is specified. Since the heat input from the outside to the 30 can be reduced and the temperature rise of the mixed gas 30 inside the nozzle 160 can be suppressed, the dry ice snow 31 can be easily generated from the mixed gas 30 introduced up to the slit portion 190 for cleaning. You can improve your ability.

Hereinafter, a dry ice snow cleaning device according to a modified example of the embodiment of the present invention will be described. The nozzle 260 of the dry ice snow cleaning device according to the modification of the embodiment of the present invention has the nozzle 160 of the dry ice snow cleaning device 1 according to the embodiment in which the configuration of the reduced diameter portion, the opening and the slit portion is one. Since they are different, the description of the same configuration as that of the nozzle 160 according to the embodiment of the present invention will not be repeated.

FIG. 7 is a cross-sectional view showing a nozzle of a dry ice snow cleaning device according to a modified example of the embodiment of the present invention. In FIG. 7, it is shown in the same cross-sectional view as in FIG.

As shown in FIG. 7, in the nozzle 260 of the dry ice snow cleaning device according to the modification of the embodiment of the present invention, the slit portion 290 is the tip of the nozzle 260 in the axial direction (X-axis direction) of the nozzle 260. It is provided from the position to the middle of the reduced diameter portion 280.

Also in the dry ice snow cleaning device according to the modified example of the embodiment of the present invention, the mixed gas 30 in which the carbon dioxide gas and the injection gas are mixed and flow into the slit portion 290 accelerates inside the reduced diameter portion 280. While dry ice snow is generated inside the slit portion 290, it spreads radially in a direction orthogonal to the axial direction of the nozzle 260 and flows, and at the same time, particles of dry ice snow are generated inside the slit portion 290 and in the vicinity of the front injection port 191. Since it can grow large, dry ice snow can be strongly sprayed over a wide angle.

The above dry ice snow cleaning equipment includes burrs, oils (organic substances), particles (powder), etc. that adhere to resin processed products, rubber products, electronic equipment, glass products, printing equipment, parts or equipment in the field of printed electronics, etc. It has effective cleaning ability for removing scale, rust (oxide film), mold release agent, adhesive, etc., and for polishing processing such as graphite (carbon) products, especially oil that adheres during machining. Has high cleaning processing ability for (organic substances).

It should be noted that the above-described embodiment disclosed this time is an example in all respects and does not serve as a basis for a limited interpretation. Therefore, the technical scope of the present disclosure is not construed solely by the embodiments described above. It also includes all changes within the meaning and scope of the claims. In the description of the above-described embodiment, the configurations that can be combined may be combined with each other.

1 Dry ice snow cleaning device, 10 carbon dioxide gas, 10L liquefied carbon dioxide gas, 20 injection gas, 30 mixed gas, 31 dry ice snow, 100 liquefied carbon dioxide gas storage container, 101 carbon dioxide gas pipe, 110 first opening / closing part, 120 throttle Unit, 120D, 171D inner diameter, 130 injection gas supply source, 131 injection gas pipe, 140 second opening / closing part, 150 mixing part, 150d mixing part reference position, 151 mixing part piping, 160, 260 nozzles, 170 large diameter part , 171 1st inner peripheral surface, 180, 280 reduced diameter part, 181 second inner peripheral surface, 182 opening, 182L, 191L, 192L width, 182W, 191W, 192W vertical width, 190,290 slit part, 191 front injection Mouth, 192 side injection port.

Claims (4)

A liquefied carbon dioxide gas supply system that supplies liquefied carbon dioxide gas,
The injection gas supply system that supplies the injection gas and
A throttle portion provided on the downstream side in the liquefied carbon dioxide gas supply system, and
A mixing unit that connects the liquefied carbon dioxide gas supply system and the injection gas supply system and mixes the carbon dioxide gas containing liquefied carbon dioxide that has passed through the throttle portion with the injection gas to generate a mixed gas.
It is connected to the mixing unit and is provided with a nozzle for injecting the mixed gas.
The nozzle includes a large diameter portion, a reduced diameter portion, and a slit portion in this order toward the axial tip of the nozzle.
The large diameter portion has a first inner peripheral surface that is connected to the mixing portion and has a constant inner diameter.
The reduced diameter portion has a second inner peripheral surface which is connected to the large diameter portion and whose diameter is reduced as the distance from the large diameter portion is increased in the axial direction.
The slit portion extends in a direction orthogonal to the axial direction and penetrates the nozzle, and is provided from the tip of the nozzle in the axial direction to a position continuous with the second inner peripheral surface.
A dry ice snow cleaning device in which the space inside the slit portion communicates with the space inside the second inner peripheral surface. The length from the mixing portion to the tip of the nozzle in the axial direction is 0.09 times or more and 0.8 times or less with respect to the length from the throttle portion to the tip of the nozzle in the axial direction. , The dry ice snow cleaning device according to claim 1. The dry ice snow cleaning device according to claim 1 or 2, wherein the pressure of the injection gas in the injection gas supply system is 0.6 MPa or more and 0.9 MPa or less. The dry ice snow cleaning device according to claim 2, wherein the length from the mixing portion to the tip of the nozzle in the axial direction is 20 mm or more and 141 mm or less.

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