GB2130701A

GB2130701A - Device for producing a block of solidified carbon dioxide

Info

Publication number: GB2130701A
Application number: GB08233598A
Authority: GB
Inventors: Yoshihisa Kawaguchi
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-11-25
Filing date: 1982-11-25
Publication date: 1984-06-06
Also published as: AU575029B2; GB2130701B; HK29887A; MY8700461A; AU2158083A; NZ206380A

Abstract

A device for producing a block of solidified carbon dioxide, consists of a high pressure vessel (2) in which liquified carbon dioxide is contained, a thermally insulated high pressure feed tube (3), and a molding box (4) having a molding chamber (10) in which the required solidified carbon dioxide is moulded in the form of a block (24). One end of the high pressure feed tube (3) is connected to the high pressure vessel (2) via a stop valve and pressure reducing valve (3a) while the other end thereof is connected to the molding box (4) via a nozzle (7). The molding box (4) has a square or rectangular configuration, and consists of a top cover (8) having the nozzle (7) secured thereto, a pair of first side walls (13) a pair of second side walls (17), and a base (11), each of these members being formed to define a square or rectangle and being adapted to be connected to or disconnected from any one of the adjacent members. The first and/or second side walls (13, 17) have therein a plurality of openings (14) through which gaseous carbon dioxide flows out, and further have therein a layer of filter material (15) having a predetermined mesh size, which filter material (15) is secured to the respective wall. <IMAGE>

Description

SPECIFICATION Device for producing a block of solidified carbon dioxide The present invention relates to a device for producing a block of carbon dioxide and more particularly relates to a portable device for molding a product of solidified carbon dioxide in a molding box which is constructed in a small size and light weight and is easily assembled or disassembled at any place.

Hitherto apparatus for manufacturing products of solidified carbon dioxide (commercially called as dry ice) are generally classified into two types, that is, large size of apparatus or installation particularly mounted in a specialized factory or plant and relatively small size of equipment or apparatus.It is pointed out as drawbacks with the aforesaid conventional equipment and apparatus, however, that the large sized one has a substantial difficulty of thermal insulation during transportation of products of solidified carbon dioxide from production side such as refrigerating factory or plant to remote locations where they are consumed and moreover requires well experienced operators for operating the same, while the small sized one is very complicated in structure, uneconomical in operation and expensive to be manufactured due to the fact that it is constructed of metallic material which leads to high thermal loss mainly because of thermal conduction.

The present invention is intended to eliminate the above mentioned drawbacks with the conventional equipment or apparatus and construct this kind of apparatus in a remarkably small size and simple structure in accordance with the conventional theory of producing a block of solidified carbon dioxide.A device for producing a block of solidified carbon dioxide in accordance with the present invention essentially comprises a high pressure vessel in which liquidified carbon dioxide is contained, a thermally insulated high pressure feed tube and a molding box in which the required product of solidified carbon dioxide is molded in the form of block, one end of said high pressure feed tube being connected to said high pressure vessel via valve means comprising a stop valve and pressure reducing valve, while the other end thereof being connected to said molding box via a nozzle means, and is operated in such a manner that when opening the stop valve, liquidified carbon dioxide is delivered to the molding box via the high pressure feed tube and nozzle means, in which liquidified carbon dioxide is ejected into the molding chamber in the form of snow falling due to adiabatic expansion, while flowing out through the layer of filter securely arranged over the inner walls of the molding chamber, resulting in snow-shaped solidified carbon dioxide accumulated in the molding chamber. Supply of liquidified carbon dioxide continues until the molding box is filled with solidified carbon dioxide having a predetermined specific density. After completion of supplying liquidified carbon dioxide the molding chamber is disassembled to take a block of solidified carbon dioxide therefrom. Preferably the high pressure feed tube for delivering liquidified carbon dioxide to the molding chamber is made of flexible material which has excellent resistibility against low temperature and high pressure. Special synthetic rubber reinforced with steel wires is preferably employed for this purpose.Further the molding box is preferably made of material having low thermal conductivity and high resistibility against low temperature such as wood and the similar material.

In an alternative embodiment of the invention the device for producing a block of solidified carbon dioxide is constructed in the type of multichamber. Specifically the molding box comprises a plurality of molding chambers of which number corresponds to that of blocks to be molded therein. The respective molding chambers are arranged side by side with partitions located therebetween. In this modified embodiment of the invention liquidified carbon dioxide is delivered to a common distributor located above the top cover of the molding box via the pressure feed tube and then is ejected into the respective molding chambers through lever operated pressure reducing valves and nozzles.

Thus it is an object of the present invention to provide a portable type device for producing a block of solidified carbon dioxide which is designed in a very small size and light weight.

It is other object of the present invention to provide a device for producing a block of solidified carbon dioxide which is easily operated merely by way of opening the valve means and disassembling the molding box.

It is another object of the present invention to provide a device for producing a block of solidified carbon dioxide which is inexpensive to be manufactured.

Other objects and advantageous features of the present invention will be obvious from the following description with reference to the accompanying drawings which forms a part of the invention.

Now the present invention will be described in more details with reference to the accompanying drawings which illustrate preferred embodiments of the invention, in which Fig. 1 is a perspective view of a device for producing a block of solidified carbon dioxide in accordance with an embodiment of the invention wherein the device is shown in a disassembled state for the purpose of being readily understood.

Fig. 2 is a front view of the device in accordance with a modified embodiment of the invention.

Fig. 3 is a vertical sectional view of the device in Fig. 2.

Fig. 4 is a side view of the device in Fig. 2, and Fig. 5 is a partial perspective view of the device in Fig. 2, wherein the essential part of the device is shown in a disassembled state.

As illustrated in Fig. 1 in which the device of the invention is generally designated by the reference numeral 1, it essentially comprises a high pressure vessel 2 in which liquidified carbon dioxide is contained, a thermally insulated high pressure feed tube 3 and a molding box 4 containing a single molding chamber in which a required block of solidified carbon dioxide is molded.

Specifically said high pressure vessel 2 is provided with a valve 5 of which connector portion 6 is connected to one end of said thermally insulated pressure feed tube 3 via a ball type pressure reducing valve 3a. In the meanwhile, the other end of the feed tube 3 is connected to a cover 8 of the molding box 4 via a nozzle means 7.

In the vicinity of the one end of the feed tube 3 is fixedly located a pressure gauge 9.

It is to be noted that the feed tube 3 which forms an essential part of the device of the invention is made of flexible material such as special synthetic rubber which has excellent properties against high pressure and low temperature, while being reinforced by means of wires of metallic material such as steel.

The molding box 4 in which a single molding chamber 10 is provided comprises a base board 11, a pair of first side walls 13, a pair of second side walls 17 and a cover 8. The base board 11 is formed with engagement grooves 12 extending in parallel to the side edges thereof in a spaced relation therefrom, into which the respective first side walls 1 3 are fit at the lower end thereof so as to stand upright. Further the first side walls 1 3 oppositely located on the base board 11 in a face to face relation are formed with a plurality of elongated openings 14 and moreover a layer of filter 1 5 fixedly secured to the inner wall thereof, said filter 1 5 having a predetermined mesh size to ensure the required permeability.The second side walls 1 7 also oppositely located on the base board 11 in a face to face relation are provided with hinges 1 6 (partly seen in Fig. 1) at the lower ends thereof, which serve for pivotally connecting the former to the latter, and moreover are adapted to come in engagement with the first side walls 1 3 by means of two engagement grooves 1 8 on the inner wall of the second side wall 17, into which the side edge portion of the standing first side wall 1 3 is fit. It is to be noted that the second side walls 1 7 are also formed with plural elongated openings 14 and have a layer of filter 15 on the inner wall thereof.Further the second side walls 1 7 are provided with a snap type locking means 1 9 at the upper end thereof, while the cover 8 is provided with engagement pieces 20 on the upper surface, whereby the second side walls 1 7 and cover 8 are connected one another in a locked state.

Thus the molding box 4 is constructed by way of the steps of fitting the first side walls 1 3 into the engagement grooves 12 on the base board 11 turning up the second side walls 17 until the side edges of the first side walls 13 fit into the engagement grooves 1 8 on the inner wall of the second side walls 1 7, placing the cover 8 over the respective upper edges of the both first and second side walls 13 and 17, and then allowing the locking means 1 9 to hang on the engagement piece 20 for ensuring tight locking.

The aforesaid cover 8, first side walls 13, second side walls 1 7 and base board 11 are made of any suitable material having excellent properties in thermal insulation and high resistivity against lower temperature such as wood, plastics or similar material. In the meanwhile, the filter 1-5 is made of any material having high resistivity against lower temperature and excellent permeability and in the illustrated embodiment plastic filters are employed.

Now operation of the device for producing a block of solidified carbon dioxide will be described below.

First, the high pressure vessel 2 having liquidified carbon dioxide contained therein is released by opening the valve 5 and thereby liquidified carbon dioxide is ejected into the molding chamber 10 through the nozzle 7 via the high pressure feed tube 3. During ejection into the molding chamber 10 liquidified carbon dioxide is pressure reduced to adiabatic expansion, resulting in a mixture of snow-shaped solidified carbon dioxide and gaseous carbon dioxide produced in the molding chamber 10.

The gaseous component in the aforesaid mixture in the molding chamber 10 flows out through the layer of the filter 1 5 and the elongated openings 14, whereas the solid component having a certain specific density is gradually accumulated against the layer of the filter 1 5 under pressure of the flowing gaseous component in the molding chamber 10 until a required block 24 of solidified carbon dioxide is molded therein. It is preferable to close the valve 5, when a predetermined period of time elapses since starting of operation.

In order to take the product 24 of solidified carbon dioxide produced in the above described manner from the molding chamber 1 0 the locking means 19 on the second side walls 17 are disconnected from the corresponding engagement pieces 20 on the cover 8. Then the cover 8 is taken aside. Now the second side walls 1 7 are ready to turn out about the hinges 1 6. Then the first side walls 13 are removed from the grooves 12 of the base board 11 in the upward direction.

Since the whole enclosure comprising the cover 8 and first and second side walls 13 and 17 are removed, the product 24 on the base board 11 can be taken out. As a resuit of repeated experiments with the use of the device in accordance with the invention it has been found that the products 24 typically has a specific density of 0.85 g/cc and is produced at a yielding rate in the range of 30 to 40%, wherein a theoretical yielding rate amounts to 47% in case of a system for producing solidified carbon dioxide in accordance with the invention. The aforesaid specific density of the product means that the same has a mechanical strength sufficient to stand practical use.

Next, another device for producing a block of solidified carbon dioxide in accordance with modified embodiment of the invention will be described with reference to Figs. 2 through 5. This modified embodiment of the invention lies in that there are provided three molding chambers 10 for a single device. It is to be noted that parts or components similar to those in Fig. 1 are given the same reference numeral.

When opening the valve 5 in the high pressure vessel 2, liquidified carbon dioxide is delivered to a common distributor 21 via the thermally insulated high pressure feed tube 3, said distributor 21 being preferably made of aluminum alloy or the like. The distributor 21 is provided with three pressure reducing valves 23 which are adapted to be separately operated by means of any of levers 22. As the first lever 22 is operated to open the first pressure reducing valve 23, liquidified carbon dioxide is ejected into the first chamber 10 in the form of snow falling in the same manner as described above. Snow-shaped solidified carbon dioxide is increasingly accumulated in the chamber 10 until the same is fully filled to a block of product 24 which is compressed and molded to the predetermined specific density. When it is found that the required product 24 is molded therein, the first lever 22 is operated in the opposite direction to close the first pressure reducing valve 23. It is obvious that molding operation in the second or third molding chamber 10 is performed by way of the same steps as those in the first molding chamber 10 as described above. Thus it is possible to produce plural blocks of products 24 at the same time or one after another in accordance with the modified embodiment of the invention.

It will be readily understood that the above described embodiments are merely illustrative of the invention and various modification or change could be made without any departure for the scope and spirit of the invention.

Claims

1. A device for producing a block of solidified carbon dioxide, comprising a vessel for containing liquified carbon dioxide under pressure, a thermally insulated feed tube for the liquified carbon dioxide, and a molding box comprising a single molding chamber in which the required solidified carbon dioxide is molded in the form of a block, one end of said feed tube being connected to said vessel via valve means comprising a stop valve and pressure reducing valve and the other end thereof being connected to said molding box via a nozzle means; wherein said molding box is constructed as a cubic structure of square or rectangular configuration and comprises a cover having said nozzle means secured thereto, a pair of first side walls oppositely located in a face-toface relationship, and a base board, each of said members being formed to define a square or rectangle and being adapted to be connected to or disconnected from any one of the adjacent members; and wherein said first and/or second side walls have therein a plurality of openings through which gaseous carbon dioxide can flow out, and further have a layer of filter material secured to the inner surface thereof.

2. A device as claimed in claim 1, wherein the first side walls are adapted to fit into engagement grooves in the base board at their lower ends so that they stand upright, and wherein the second side walls are adapted to turn about hinge means which are secured to the side edges of the base board so that they connect to the first side walls by virtue of the fact that the vertically extending side edges of the first side walls fit into engagement grooves in the inner surface of the second side walls.

3. A device as claimed in claim 1 or 2, wherein the second side walls are provided with locking means at the upper ends thereof, which locking means are adapted to engage with engagement members secured to the side edges of the cover, whereby the second side walls, together with the first side walls, are fixed to the cover.

4. A device as claimed in claim 3, wherein the locking means on the upper end of the second side wall is a snap type locking means.

5. A device as claimed in any of claims 1 to 4, wherein the plurality of openings in the first and/or second side walls comprise a plurality of vertically extending elongated openings arranged parallel to each other in a spaced relationship.

6. A device as claimed in any of claims 1 to 5, wherein a pressure gauge is arranged between the one end of the feed tube and the pressure reducing valve on the vessel.

7. A device as claimed in any of claims 1 to 6, wherein the feed tube is made of flexible material having high resistance to low temperature and high pressure.

8. A device as claimed in any of claims 1 to 7, wherein the molding box is made of material having a low thermal conductivity and a high resistance to pressure.

9. A device for producing a block of solidified carbon dioxide, comprising a vessel for containing liquified carbon dioxide under pressure, a thermally insulated feed tube for the liquified carbon dioxide, a common distributor, and a molding box comprising a plurality of molding chambers in which the required number of blocks of solidified carbon dioxide are molded, one end of said feed tube being connected to said vessel via valve means comprising a step valve and pressure reducing valve and the other end thereof being connected to said molding box via said distributor, via lever operated pressure reducing valves and via a plurality of nozzle means; wherein the molding box is constructed as a cubic structure of rectangular configuration and comprises a cover having a plurality of nozzle means secured thereto, pairs of first side walls oppositely located in a face-to-face relationship, and a base board, each of said members being formed to define a square or rectangle and being adapted to be connected to or disconnected from any one of the adjacent members; and wherein said first and/or second side walls have therein a plurality of openings through which gaseous carbon dioxide can flow out, and further have a layer of filter material secured to the inner surface thereof.

10. A device as claimed in claim 9, being adapted to produce a plurality of blocks of solidified carbon dioxide in the respective molding chambers at the same time or one after another by opening of the lever operated pressure reducing valves at the same time or successively.

1 A device as claimed in claim 9 or 10, wherein the number of pairs of first side walls corresponds to the required number of blocks of solidified carbon dioxide to be molded, the respective pairs of first side walls being arranged side by side.

12. A device as claimed in claim 1 wherein the respective second side wall is formed with engagement grooves on the inner wall thereof, of which the number corresponds to that of the first side walls.

13. A device claims in any of claims 9 to 12, wherein the respective first side walls are adapted to fit into engagement grooves in the base board at their lower ends so that they stand upright, and wherein the second side wails are adapted to turn about hinge means on the side edges of the base board so that they connect to the first side walls by virtue of the fact that the vertically extending side edges of the first side walls fit into engagement grooves in the inner surface of the second side walls.

14. A device as claimed in any of claims 9 to 13, wherein the second side walls are provided with locking means at the upper ends thereof, which locking means are adapted to engage with engagement members on the side edges of the cover, whereby the second side walls, together with the first side walls, are fixed to the cover.

1 5. A device as claimed in claim 14, wherein the locking means on the upper end of the second side wall is a snap type locking means.

16. A device as claimed in any of claims 9 to 1 5, wherein the plurality of openings in the first and/or second side walls comprise a plurality of vertically extending elongated openings arranged parallel to each other in a spaced relationship.

1 7. A device as claimed in any of claims 9 to 16, wherein a pressure gauge is arranged at one end of the distributor.

1 8. A device as claimed in any of claims 9 to 17, wherein the feed tube is made of flexible material having a high resistance to low temperature and high pressure.

1 9. A device as claimed in any of claims 9 to 18, wherein the molding box is made of material having a low thermal conductivity and a high resistance to pressure.

20. A device for producing a block of solidified carbon dioxide, comprising a high pressure vessel for containing liquified carbon dioxide, a flexible thermally insulated high pressure feed tube, a common distributor, and a molding box comprising a plurality of molding chambers in which a predetermined number of solidified carbon dioxide blocks are molded, one end of said high pressure feed tube being connected to said high pressure vessel via valve means comprising a stop valve and pressure reducing valve and the other end thereof being connected to said molding box via said distributor, via lever operated pressure reducing valves and via a plurality of nozzle means; wherein said molding box has a cubic structure of rectangular configuration and includes a top cover having the plurality of nozzle means secure thereof, pairs of first side walls oppositely located in a face-to-face relationship, a pair of second side walls oppositely located in a face-toface relationship, and a base board, each of said members being formed to define a square or rectangle and being adapted to be connected to or disconnected from any one of the adjacent members; and wherein said first and/or second side walls are provided with a plurality of openings through which gaseous carbon dioxide can flow out and with a layer of filter material of predetermined mesh size, the filter material being secured to the inner surface thereof.

21. A device for producing a block of solidified carbon dioxide, substantially as hereinbefore described with reference to, and as shown in, Figure 1 or Figures 2 to 5 of the drawings.

22. A block of solidified carbon dioxide, when produced in a device as claimed in any of claims 1 to21.