JP7706969B2 - Dry ice pellet manufacturing equipment - Google Patents

Description

The present invention relates to a dry ice pellet manufacturing device.

JP 2006-52113 A (Patent Document 1) is a prior document that discloses the configuration of a dry ice pellet manufacturing method and device. The dry ice pellet manufacturing device described in Patent Document 1 comprises a molding chamber, a molding plate, an extrusion means, a shielding means, and a cutting means. The molding plate is provided at one end side of the longitudinal direction of the molding chamber, and has a large number of holes formed therein. The extrusion means is capable of compressing the snow-like dry ice in the molding chamber toward the molding plate. The shielding means prevents the snow-like dry ice from leaking from the molding chamber. The cutting means cuts the rod-shaped dry ice extruded from the holes in the molding plate.

JP 2006-52113 A

In the dry ice pellet manufacturing device described in Patent Document 1, a member for shielding the snow-like dry ice inside the cylinder and a member for cutting the compressed dry ice are provided separately, so the number of components of the device increases and the structure of the device becomes complex.

The present invention has been made to solve the above problems, and aims to provide a dry ice pellet manufacturing device that has a simple structure that combines a shielding structure for snow-like dry ice and a cutting structure for compressed dry ice.

The dry ice pellet manufacturing device according to the present invention includes a cylinder, a nozzle section, a piston, and a cutting plate. The cylinder extends in the axial direction and contains snow-like dry ice. The nozzle section is disposed at one end of the cylinder in the axial direction and has multiple shaping holes. The piston is disposed inside the cylinder so as to be able to reciprocate in the axial direction. The cutting plate is disposed outside the cylinder so as to be able to reciprocate in a direction perpendicular to the axial direction and opens and closes the multiple shaping holes while sliding with the nozzle section. When the multiple shaping holes are closed by the cutting plate, the piston moves toward the nozzle section, compressing the snow-like dry ice. When the cutting plate moves to open the multiple shaping holes, the piston moves further toward the nozzle section, pushing out the compressed snow-like dry ice from the multiple shaping holes. When the cutting plate moves in a direction to close the multiple shaping holes, the pushed-out portion of the compressed snow-like dry ice is cut off.

In one embodiment of the present invention, the piston moves in the direction toward the nozzle and the cutting plate opens and closes multiple forming holes in a continuous alternating manner, cutting the compressed snow-like dry ice every time a certain amount is extruded.

In one embodiment of the present invention, the cutting plate includes a sliding surface portion and an inclined surface portion. The sliding surface portion slides against the nozzle portion. The inclined surface portion intersects with the sliding surface portion at an acute angle. The portion extruded from the compressed snow-like dry ice is cut at the edge where the sliding surface portion intersects with the inclined surface portion.

In one embodiment of the present invention, the cutting plate is made of resin.

In one embodiment of the present invention, the sliding surface is polished.

According to the present invention, it is possible to integrate the shielding structure for snow-like dry ice and the cutting structure for compressed dry ice into a simple structure.

1 is a schematic diagram showing a configuration of a dry ice pellet manufacturing system according to one embodiment of the present invention. FIG. 1 is a cross-sectional view showing a configuration of a dry ice pellet manufacturing apparatus according to an embodiment of the present invention. 2 is a cross-sectional view showing a state in which snow-like dry ice is compressed in a dry ice pellet manufacturing apparatus according to one embodiment of the present invention. FIG. 4 is a cross-sectional view showing a state in which compressed dry ice is pushed out of a molding hole in the dry ice pellet manufacturing apparatus according to one embodiment of the present invention. FIG. 2 is a cross-sectional view showing a state in which compressed dry ice is cut in the dry ice pellet manufacturing apparatus according to one embodiment of the present invention. FIG. 2 is a graph showing the operational relationship between components of the dry ice pellet manufacturing apparatus according to one embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of a dry ice pellet manufacturing apparatus according to a comparative example. 10 is a cross-sectional view showing a state in which compressed dry ice is pushed out of a molding hole in a dry ice pellet manufacturing apparatus according to a comparative example. FIG. 1 is a cross-sectional view showing a state in which compressed dry ice is cut in a dry ice pellet manufacturing apparatus according to a comparative example. FIG. 1 is a graph showing the standard error of the length of dry ice pellets according to an embodiment and a comparative example.

The following describes a dry ice pellet manufacturing device according to one embodiment of the present invention with reference to the drawings. In the following description of the embodiment, the same or corresponding parts in the drawings are given the same reference numerals, and the description thereof will not be repeated.

Figure 1 is a schematic diagram showing the configuration of a dry ice pellet manufacturing system according to one embodiment of the present invention. As shown in Figure 1, the dry ice pellet manufacturing system 1 according to this embodiment includes a liquefied carbon dioxide gas supply system 10 and a dry ice pellet manufacturing device 20.

The liquefied carbon dioxide gas supply system 10 includes a liquefied carbon dioxide gas storage container 100, a carbon dioxide gas pipe 101, a first opening/closing section 102, and a throttle section 103. The liquefied carbon dioxide gas supply system 10 further includes a pressure gauge that measures the pressure inside the carbon dioxide gas pipe 101.

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 carbon dioxide gas.

The first opening/closing unit 102 is provided midway through the carbon dioxide gas pipe 101. The first opening/closing unit 102 is configured as a valve that can be opened and closed manually. The first opening/closing unit 102 may also be configured as a valve that can be opened and closed automatically.

The throttling section 103 is provided downstream of the first opening/closing section 102 in the liquefied carbon dioxide supply system 10. In one embodiment of the present invention, the throttling section 103 is configured by an orifice plate. The flow rate of the liquefied carbon dioxide is adjusted by the throttling section 103. The temperature of the liquefied carbon dioxide decreases due to adiabatic expansion in the throttling section 103. As the temperature of the liquefied carbon dioxide decreases, snow-like dry ice is formed.

The dry ice pellet manufacturing device 20 is located downstream of the constriction section 103. Snow-like dry ice is supplied to the dry ice pellet manufacturing device 20.

Figure 2 is a cross-sectional view showing the configuration of a dry ice pellet manufacturing device according to one embodiment of the present invention. As shown in Figure 2, the dry ice pellet manufacturing device 20 according to this embodiment includes a cylinder 110, a nozzle portion 120, a piston 130, a cutting plate 140, and a stand 150.

The cylinder 110 is a hollow cylindrical member. The cylinder 110 extends in the axial direction and contains the snow-like dry ice 2. The cylinder 110 is made of, for example, iron or aluminum.

The cylinder 110 has a supply section 111 and a discharge section 112 at a portion of the circumference. The supply section 111 supplies the snow-like dry ice 2 supplied from the liquefied carbon dioxide gas supply system 10 to the inside of the cylinder 110. The discharge section 112 discharges the gas present inside the cylinder 110 to the outside when the snow-like dry ice 2 is compressed as described below.

The nozzle portion 120 is a plate-like member disposed at one end of the cylinder 110 in the axial direction. The nozzle portion 120 includes an inner surface portion 122 located on the cylinder 110 side and an outer surface portion 123 located on the opposite side to the cylinder 110. The nozzle portion 120 is made of, for example, iron or aluminum.

The nozzle portion 120 is provided with a plurality of molding holes 121. In this embodiment, the plurality of molding holes 121 are provided in parallel in the axial direction of the cylinder 110. Each of the plurality of molding holes 121 connects and penetrates the inner surface portion 122 and the outer surface portion 123. The diameter of each of the plurality of molding holes 121 is, for example, 10 mm.

The piston 130 is a columnar member disposed inside the cylinder. The piston 130 can move back and forth in the axial direction of the cylinder 110. The piston 130 is made of, for example, iron or aluminum.

The cutting plate 140 is a plate-shaped member disposed on the outside of the cylinder 110. The cutting plate 140 can move back and forth in a direction perpendicular to the axial direction of the cylinder 110. The cutting plate 140 can move back and forth by a drive mechanism (not shown). The cutting plate 140 opens and closes the multiple forming holes 121 while sliding against the nozzle portion 120.

The cutting plate 140 is made of resin. For example, the cutting plate 140 is made of polyacetal. Note that the material of the cutting plate 140 is not limited to resin, and may be a metal such as iron or aluminum.

The cutting plate 140 has a sliding surface portion 141, an inclined surface portion 142, and a ridge portion 143.

The sliding surface portion 141 is located on the nozzle portion 120 side of the cutting plate 140. The sliding surface portion 141 slides against the nozzle portion 120 when the cutting plate 140 opens and closes the multiple forming holes 121. Specifically, the sliding surface portion 141 slides against the outer surface portion 123.

The sliding surface portion 141 is polished. The surface roughness (Ra) of the sliding surface portion is, for example, 0.8 μm or less. The sliding surface portion 141 is, for example, buffed.

The inclined surface portion 142 is located on the opposite side of the cutting plate 140 from the nozzle portion 120. The inclined surface portion 142 intersects with the sliding surface portion 141 at an acute angle.

The ridge portion 143 is the portion where the sliding surface portion 141 and the inclined surface portion 142 of the cutting plate 140 intersect. At the ridge portion 143, the portion extruded from the compressed snow-like dry ice described below is cut. When viewed from the cross-sectional direction of the cutting plate 140, the ridge portion 143 has a curved shape and connects the sliding surface portion 141 and the inclined surface portion 142. Note that the shape of the ridge portion 143 is not limited to a curved shape, and may be a straight line connecting the sliding surface portion 141 and the inclined surface portion 142.

The stand 150 is a member that supports the components of the dry ice pellet manufacturing device 20. The stand 150 is provided at the bottom of the dry ice pellet manufacturing device 20. The stand 150 is fixed to the cylinder 110 by a fixing member (not shown). The stand 150 is located on an extension line of the axial direction of the cylinder 110. The stand 150 is disposed below the cutting plate 140. The stand 150 can slide with the cutting plate 140 so that the formed dry ice pellets do not remain between the cutting plate 140 and the stand 150. Note that the stand 150 may be configured to have a small gap between it and the cutting plate 140.

The stand 150 is provided with a hopper 151. The hopper 151 is a container that holds the formed dry ice pellets.

The operation of the dry ice pellet manufacturing device 20 according to one embodiment of the present invention is described below.

Figure 3 is a cross-sectional view showing the state in which snow-like dry ice is compressed in a dry ice pellet manufacturing apparatus according to one embodiment of the present invention. Figure 4 is a cross-sectional view showing the state in which compressed dry ice is pushed out of a molding hole in a dry ice pellet manufacturing apparatus according to one embodiment of the present invention. Figure 5 is a cross-sectional view showing the state in which compressed dry ice is cut in a dry ice pellet manufacturing apparatus according to one embodiment of the present invention.

First, as shown in FIG. 2, snow-like dry ice 2 is supplied from supply unit 111 into cylinder 110. The snow-like dry ice 2 accumulates inside cylinder 110. When snow-like dry ice 2 is supplied into cylinder 110, cutting plate 140 closes multiple forming holes 121. This prevents snow-like dry ice 2 from leaking out of multiple forming holes 121.

Next, as shown in FIG. 3, with the multiple forming holes 121 closed by the cutting plate 140, snow-like dry ice 2 is supplied into the cylinder 110, and the piston 130 moves toward the nozzle portion 120, compressing the snow-like dry ice 2 while preventing leakage of the snow-like dry ice 2. In this embodiment, the compressed snow-like dry ice 3 is shaped to have the desired density by adjusting the time during which the piston 130 moves at a constant speed to compress the snow-like dry ice 2.

The compressive stress of the piston 130 is, for example, 20 MPa. At the same time as the compressed snow-like dry ice 3 is formed, the gas remaining in the cylinder 110 is discharged to the outside through the discharge section 112.

Next, as shown in FIG. 4, when the cutting plate 140 has moved to open the multiple forming holes 121, the piston 130 moves further toward the nozzle portion 120, pushing out the compressed snow-like dry ice 3 from the multiple forming holes 121. By adjusting the time that the piston 130 pushes out the compressed snow-like dry ice 3, the length of the pushed-out portion 3p of the compressed snow-like dry ice in the axial direction of the cylinder 110 is adjusted. For example, the compressed snow-like dry ice 3 is pushed out 100 mm by setting the pushing time of the piston 130 to 50 msec.

Next, as shown in FIG. 5, the cutting plate 140 moves in a direction that closes the multiple forming holes 121, cutting the portion 3p extruded from the compressed snow-like dry ice 3. The portion 3p extruded from the compressed snow-like dry ice is cut to become dry ice pellets 4. The dry ice pellets 4 are stored in the hopper 151.

In one embodiment of the present invention, the dry ice pellet manufacturing device 20 extrudes the dry ice pellets 4 downward, but is not limited to downward extrusion, and may be configured to extrude the dry ice pellets 4 upward.

Figure 6 is a graph showing the operational relationships of the components of a dry ice pellet manufacturing device according to one embodiment of the present invention.

As shown in Figures 2 to 6, the piston 130 moves in the direction toward the nozzle portion 120 and the cutting plate 140 opens and closes the multiple forming holes 121 in a continuous alternating manner, so that the compressed snow-like dry ice 3 is cut every time a certain amount is extruded.

Specifically, as shown in FIG. 6, the piston 130 descends from the raised position and stops at time t1 when the snow-like dry ice 2 is compressed, and the cutting plate 140 starts moving in the direction to open the multiple forming holes 121. At time t2, the movement of the cutting plate 140 in the direction to open the multiple forming holes 121 is completed, and the piston 130 starts descending. As a result, the compressed snow-like dry ice 3 is pushed out from the multiple forming holes 121. At time t3, the piston 130 stops descending and the cutting plate 140 starts moving in the direction to close the multiple forming holes 121. At time t4, the movement of the cutting plate 140 in the direction to close the multiple forming holes 121 is completed. As a result, the portion 3p pushed out from the compressed snow-like dry ice is cut by the cutting plate 140, and the dry ice pellet 4 is formed. This cycle from time t1 to time t4 is repeated until the piston 130 descends to the descended position and the compressed snow-like dry ice 3 in the cylinder 110 is discharged from the cylinder 110.

Here, we will explain a dry ice pellet manufacturing device according to a comparative example of one embodiment of the present invention. The dry ice pellet manufacturing device according to the comparative example of one embodiment of the present invention differs from the dry ice pellet manufacturing device 20 according to one embodiment of the present invention in the configuration of the cutting plate and the operation of the piston and cutting plate, so we will not repeat the description of the configuration that is similar to the dry ice pellet manufacturing device 20 according to one embodiment of the present invention.

Figure 7 is a cross-sectional view showing the configuration of a dry ice pellet manufacturing device according to a comparative example. As shown in Figure 7, the dry ice pellet manufacturing device 90 according to the comparative example includes a cylinder 110, a nozzle portion 120, a piston 130, a cutting plate 940, and a stand 150.

The cutting plate 940 in this comparative example has a sliding surface portion 941, a pressing surface portion 942, and a ridge portion 943.

The sliding surface portion 941 is located on the nozzle portion 120 side of the cutting plate 940. The sliding surface portion 941 slides against the nozzle portion 120 when the cutting plate 940 opens and closes the multiple molding holes 121.

The pressing surface portion 942 is a surface that intersects with the sliding surface portion 941 at a right angle. The ridge portion 943 is the portion of the cutting plate 940 where the sliding surface portion 941 and the pressing surface portion 942 intersect.

Figure 8 is a cross-sectional view showing the state in which compressed dry ice is pushed out of the forming hole in the dry ice pellet manufacturing device of the comparative example. Figure 9 is a cross-sectional view showing the state in which compressed dry ice is cut in the dry ice pellet manufacturing device of the comparative example.

In the comparative example of the dry ice pellet manufacturing device 90, the piston 130 continues to move without stopping until it reaches the nozzle portion 120.

As a result, as shown in FIG. 8, the compressed snow-like dry ice 3 is pushed out and breaks when it comes into contact with the stand 150. The remaining broken portions of the portion 3p pushed out of the compressed snow-like dry ice remain as they were pushed out of the multiple forming holes 121.

As shown in FIG. 9, after the compressed snow-like dry ice 3 inside the cylinder 110 is pushed outward, the cutting plate 940 moves in a direction to close the multiple forming holes 121. Either the ridge portion 943 or the pressing surface portion 942 comes into contact with the portion 3p pushed out from the compressed snow-like dry ice. This causes the remaining broken portion of the portion 3p pushed out from the compressed snow-like dry ice to be cut off.

In the comparative example, the remaining broken portion of the portion 3p extruded from the compressed snow-like dry ice is not necessarily cut off at the ridge 943. The dry ice pellet 4A in the comparative example includes a portion of the portion 3p extruded from the compressed snow-like dry ice that abuts against the stand 150 and is broken off, and a portion that is cut off by the cutting plate 940.

Figure 10 is a graph showing the standard error of the length of dry ice pellets according to one embodiment and a comparative example. Figure 10 shows the standard error of the length of dry ice pellets in the axial direction of the cylinder 110 when 27 dry ice pellets each of one embodiment and a comparative example are measured.

As shown in FIG. 10, the standard error of the length of the dry ice pellets in this embodiment is smaller than that in the comparative example. Specifically, the standard error of the length of the dry ice pellets is about 1.4 mm in the comparative example and about 0.8 mm in this embodiment. The distribution range of the length of the dry ice pellets is 5 mm or more and 30 mm or less in the comparative example and 5 mm or more and 12 mm or less in this embodiment.

In the dry ice pellet manufacturing device 20 according to one embodiment of the present invention, the cutting plate 140 closes the multiple forming holes 121 when compressing the snow-like dry ice 2, and the compressed snow-like dry ice 3 can be cut by changing the multiple forming holes 121 from an open state to a closed state, so that the shielding structure for the snow-like dry ice and the cutting structure for the compressed dry ice can be integrated into a simple structure.

In the dry ice pellet manufacturing device 20 according to one embodiment of the present invention, the movement of the piston 130 toward the nozzle portion 120 and the opening and closing of the multiple forming holes 121 by the cutting plate 140 are alternately and continuously performed, so that the compressed snow-like dry ice 3 is cut every time a certain amount is extruded, thereby suppressing variation in the length of the dry ice pellets 4 that are formed.

In the dry ice pellet manufacturing device 20 according to one embodiment of the present invention, the compressed snow-like dry ice 3 can be cut at the ridge portion 143 where the sliding surface portion 141 and the inclined surface portion 142 intersect, improving the sharpness of the cutting plate 140 and suppressing variation in the length of the dry ice pellets 4.

In the dry ice pellet manufacturing device 20 according to one embodiment of the present invention, the cutting plate 140 is made of resin, which reduces the thermal conductivity of the cutting plate 140 and suppresses the cooling of the cutting plate 140 by the dry ice pellets 4, thereby suppressing the generation of ice blocks on the surface of the cutting plate 140.

In the dry ice pellet manufacturing device 20 according to one embodiment of the present invention, the sliding surface portion 141 of the cutting plate 140 is polished, which makes it difficult for dry ice that could become lumpy dry ice to adhere to the surface of the sliding surface portion 141, thereby suppressing the generation of ice chunks on the surface of the cutting plate 140.

The dry ice pellet manufacturing device 20 according to one embodiment of the present invention consolidates the snow-like dry ice shielding structure and the compressed dry ice cutting structure into a simple structure, thereby making it possible to miniaturize the device and increase the options for where the device can be installed, thereby contributing to the achievement of, for example, goal 7, "Affordable and clean energy" in the Sustainable Development Goals (SDGs).

In addition, the dry ice pellet manufacturing device 20 according to one embodiment of the present invention can obtain only the dry ice pellets that are needed by suppressing the variation in length of the dry ice pellets that are formed, and can therefore contribute to achieving the goal of, for example, "12. Responsible Consumption and Production" in the SDGs.

The above disclosed embodiments are illustrative in all respects and are not intended to be a basis for restrictive interpretation. Therefore, the technical scope of the present disclosure should not be interpreted solely by the above-described embodiments. Furthermore, all modifications within the meaning and scope equivalent to the claims are included. In the description of the above-described embodiments, configurations that can be combined may be combined with each other.

1 dry ice pellet manufacturing system, 2 snow-like dry ice, 3 compressed snow-like dry ice, 3p part extruded from compressed snow-like dry ice, 4, 4A dry ice pellets, 10 liquefied carbon dioxide gas supply system, 20, 90 dry ice pellet manufacturing device, 100 liquefied carbon dioxide gas storage container, 101 carbon dioxide gas pipe, 102 first opening and closing part, 103 throttle part, 110 cylinder, 111 supply part, 112 discharge part, 120 nozzle part, 121 forming hole, 122 inner part, 123 outer part, 130 piston, 140, 940 cutting plate, 141, 941 sliding surface part, 142 inclined surface part, 143, 943 ridge part, 150 stand, 151 hopper, 942 pressing surface part.

Claims (4)

A cylinder extending in an axial direction and containing snow-like dry ice;
a nozzle portion disposed at one end of the cylinder in the axial direction and having a plurality of molding holes;
a piston disposed inside the cylinder so as to be reciprocally movable in the axial direction;
A stand located on an extension line of the axial direction of the cylinder;
a cutting plate that is arranged outside the cylinder so as to be reciprocable in a direction perpendicular to the axial direction, that opens and closes the plurality of molding holes while sliding against the nozzle portion and the base , and that is made of resin ;
When the plurality of forming holes are closed by the cutting plate, the piston moves toward the nozzle portion, whereby the snow-like dry ice is compressed,
When the cutting plate is moved to open the multiple shaping holes, the piston is further moved toward the nozzle portion to push out the compressed snow-like dry ice from the multiple shaping holes,
A dry ice pellet manufacturing apparatus in which the cutting plate moves in a direction that closes the multiple forming holes, thereby cutting off the extruded portion of the compressed snow-like dry ice. The dry ice pellet manufacturing device according to claim 1, in which the movement of the piston toward the nozzle portion and the opening and closing of the multiple forming holes by the cutting plate are alternately and continuously performed, so that the compressed snow-like dry ice is cut every time a certain amount is extruded. The cutting plate has a sliding surface portion that slides against the nozzle portion,
an inclined surface portion intersecting the sliding surface portion at an acute angle;
3. The dry ice pellet manufacturing device according to claim 1, wherein the extruded portion is cut off from the compressed snow-like dry ice at a ridge where the sliding surface portion and the inclined surface portion intersect. The dry ice pellet manufacturing apparatus according to claim 3 , wherein the sliding surface portion is polished.

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