NL8105670A - DEVICE FOR PRESSURING BARRELS. - Google Patents

Description

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Device for pressurizing vessels.

Numerous products, such as non-alcoholic drinks and beer, are packed in barrels under pressure. The pressure under which these products are packed is obtained by means of the carbon dioxide in the product. Namely, the vessel is pressurized due to the nature of the product in the vessel.

Such barrels, especially two-piece aluminum and steel cans, are manufactured with the smallest possible wall thickness to reduce the amount of metal required to form the barrel and thereby the cost of the barrel. These barrels, as well as other barrels such as plastic bottles and the like, make great use of the internal pressure of the product in the barrel to improve the tear strength and the strength of the wall of the barrel.

Irrespective of whether the carbonated products are packaged in a can, bottle or other vessel, the air is removed from the space above the product in the vessel before the lid is closed on the vessel, by means of the carbonic acid released from the product. The removal of this air from the space above the product in the vessel is important to prevent spoilage of the product under the influence of the air.

Recently it has become more and more popular to pack 25 non-carbonated products, such as fruit juices and the like, in the same barrels that were previously only used for carbonated products. Over there ·. however, these products have been calmed, namely, no pressure is generated in the vessel due to the carbonic acid after closing the vessel, it cannot be assumed that the strength of a filled metal vessel, a plastic bottle and other similar vessels, nor it can be assumed that the air is removed from the open space above the product before sealing the vessel by means of a sealing element.

It is beaker to physically mix gaseous nitrogen in 8 1 0 5 6 7 0 _____ s -2-such soothed products before packaging, in order to have gaseous nitrogen available both for pressurizing the vessel and for removal of the air from the free space at the top of the vessel just before hermetically sealing the vessel. However, gaseous nitrogen does not easily mix with such products and therefore such a process is very time consuming and expensive.

It is also known from British Patent 1,455,652 that vessels filled with calmed products can be pressurized by introducing a drop of liquid nitrogen or a liquefied noble gas into the filled vessel and immediately closing the vessel.

After closing, the evaporating liquid gas now present in the form of gas pressurizes the vessel.

Unfortunately, the British patent does not show an apparatus for obtaining this result.

The present invention relates to an apparatus for injecting liquid nitrogen or other liquefied gas, such as a noble gas, including argon and the like, into containers avoiding the drawbacks of the prior methods. The injection device of the present invention includes a fluidized chamber, means for allowing certain amounts of liquid gas to be injected into vessels as they pass through the device and a combination of float shut-off means for maintaining fluid levels and gas pressures of a certain height in the establishment. The device also includes means for maintaining a gaseous atmosphere around the outflow nozzle, thereby preventing air and moisture from entering the device causing a freezing and thereby inoperative operation of the device.

The liquid gas injection device according to the present invention will be further described with reference to the drawing. In the drawing: Fig. 1 schematically shows a device according to the invention for injecting liquid gas, Fig. 2 shows a cross section of the injection unit, Fig. 3 shows a top view of the injection unit and 8105670. Fig. 4 is a top view of the bottom plate of the injection unit.

Figure 1 shows a schematic of a liquid nitrogen injection device.

Although special reference is made to liquid nitrogen, it will be understood that other liquefied gases that can be mixed with the product to be packaged, such as noble gases, more particularly argon, could be used instead of nitrogen. A reservoir 19 is the source of liquid nitrogen from the device. Such reservoirs 10 are commercially available and include pressure release means (not shown) so that the gas pressure of the evaporating liquid nitrogen in the reservoir 10 will not become too high for the strength of the reservoir 10. Within the reservoir 10 a pair of pipes 12 and 14 are located. The pipe 12 is located above the level of the liquid nitrogen in the reservoir 10 and is used to control the pressure of the evaporating gaseous nitrogen in the reservoir 10 above the liquid nitrogen, at a height usable for the device 20. For example, conduit 12 includes a valve 16, a heater 18 for heating the gaseous nitrogen supplied through conduit 12 at a temperature of about -129.1 ° C, and a back pressure regulator 20. The back pressure regulator 20 is set at a pressure equal to that desired within the device, which may be between 2109.3 and 3515.5 kg per square meter of overpressure and preferably at 2812.4 kg per square meter of overpressure. This pressure is much lower than the pressure which may prevail in the reservoir 10 and which is controlled by the internal pressure relief device.

The purpose of the heating device 18 is to prevent freezing of the back pressure regulator 20 and to render it inoperative.

The conduit 14 is in the liquid nitrogen itself. Liquid nitrogen is pumped through this line within the reservoir 10 under the influence of the internal pressure. The valve 17 controls the amount of liquid gas flowing from the line 14 to the insulated line 22. The conduit 22 is preferably formed by a metal pipe covered with foam rubber or other insulating material to minimize heat losses as much as possible. The conduit 22 is connected at the other end to the liquid gas inlet 38 of an injection unit 24. Barrels such as metal cans 26 pass underneath the injector 24. The passage of these barrels along the bottom of the device 24 is detected by detector 28 and a signal is sent via line 30 to a controller 32. The controller 32 provides this signal via the line 34 and an electrical connection 10. device 36 passes to the Injector 24, and the injector 24 injects a certain amount of liquid nitrogen into the vessel 26. This operation will be described in more detail below.

Figures 2 and 3 show the injection unit 24.

The inlet conduit 40 is surrounded by an insulated cover 38. The inlet conduit 40 debouches in the connector to a liquid chamber 42. A float 46 is located within the liquid chamber 42, which float 46 rises and falls at the level of the liquid nitrogen in the chamber 42. A baffle 44 is provided at the inlet into the chamber 42 to prevent the inflowing liquid gas from colliding with the float 46 and thereby preventing its operation.

During operation of the device, the float 46 will initially rest on the bottom of the chamber 42. At the start of operation of the device, the temperature of the injection device 24 and of the inlet lines 22 and 40 is well below the boiling point of liquid nitrogen. Thus, in the beginning, all or nearly all nitrogen entering chamber 42 is gaseous. This gas escapes through a shut-off mechanism comprising a valve 56 located within the valve seat 85 in the open position, a rod 54 and a cover 48, all of which are attached to the float 46. The cover 48 has a number of openings 50 through which gas can enter. The gas flows through a pipe 52 through which the float 46 can move, through a valve seat 58 past a chamber 60 through an opening 62, through another chamber 64 and an outlet opening 68. As a result, the internal parts of the device 24 will be cooled and the fill the device with nitrogen 8105670 -5-, removing all air from the device and preventing any moisture present from freezing.

As the device 24 gets colder, more and more liquid nitrogen enters via the line 40. As a result, the float 46 will move upwards. Some liquid nitrogen will still evaporate to gas, maintaining a pressure above the float 46, which pressure is measured via the line 70 which is connected on the one hand to the chamber 42 and on the other hand to the pressure gauge 72.

During the upward movement of the float 46, the valve 56 is still open, allowing some liquid nitrogen to evaporate and escape through the valve seat 58 and through the aforementioned venting system where the nitrogen can escape as gas. Finally, an equilibrium can be obtained with the valve 56 slightly opened or closed within the valve seat 58 with additional liquid nitrogen entering through the line 40 and the float 46 rising while an increase in the gas pressure above the float 46 the float 46 moves down.

The injection of liquid nitrogen from the unit 24 into the vessels 26 is controlled by a needle valve 78 positioned within the valve seat 80. When the detector 28 detects the presence of a vessel 26, the controller 25 32 gives a signal to the coil 74 When the coil 74 is energized, this pulls the valve rod 76 upward allowing liquid nitrogen to flow from the pipe 47, which pipe 77 communicates with the chamber 42 through openings 69 and 71 to allow liquid nitrogen to escape through the valve -30 seat 80 and through the outlet line 82 to the vessel 26. The coil 74 is a high speed magnetic coil capable of opening and closing at a frequency of more than 3000 strokes per minute. This is more than sufficient to allow the device to be installed in any filling device 35, the fastest of which rarely handles more than 1500 units per minute.

The length of time during which the coil 74 keeps the valve 78 open is controlled by the controller 32. A start signal from the sensor 28 initiates a timer within the 8105670 _____ -6 unit 32 to energize the coil 74 and the de-energize it again according to a preset time lapse. When the coil 74 is de-energized, the spring 75 presses the valve stem 76 down, the needle valve 78 rests on the valve seat 80 and the flow of liquid nitrogen is interrupted.

As previously noted, as the float 46 moves up and down, gaseous nitrogen 10 escapes through the valve seat 58 and optionally flows into the chamber 64 and escapes through the outlet 68. As shown most clearly in Figure 4, a number of heaters 86 disposed within the bottom plate 83 to maintain a temperature sufficiently far above the temperature of the liquid nitrogen to ensure that the nitrogen is in the gaseous form when the nitrogen is evacuated through the outlet 68 along with the liquid nitrogen being injected through the exhaust line 82. This maintains a gaseous nitrogen atmosphere around the exhaust line 82 and thereby prevents air from entering it, thereby preventing the exhaust line 82 from freezing. These heaters 86 also provide a temperature of the bottom plate 83 that is sufficiently far above the freezing point of the product in the vessel 26 that any product spilled on the bottom plate 83 will not freeze thereon.

As shown in Figure 4, additional gas exhaust vents 100 are provided around the exhaust line 82. This provides additional diversion options for the liquid nitrogen in the chamber 64. An insert plate 85 can be rotated to change the position of the exhaust from the injector 24 via the outlet conduit 82. The outlet conduit 82 can be placed at an angle of about 10 to 30 relative to the bottom of the unit 24, with an angle of about 20 ° being preferred.

355 ml aluminum canisters can be pressurized with an injection of about 0.1 to 0.2 ml of liquid nitrogen per can. The amount of injected liquid nitrogen is, of course, determined by the length of time 8105670 -7- during which the valve 80 remains open and by the speed of the bushings 26 passing below the injection unit 24.

After a system of vessels has been filled, the device 24 can be closed temporarily. However, if air enters the unit enομ and condenses moisture inside the unit at the same time, freezing could occur causing difficulties in recommissioning. Therefore, heating devices 73 controlled by the thermostat 84 can be operated during the shutdown period, with the heating devices turning off again when the device is put into operation.

The major parts of the unit 24 are housed 15 in a pair of jackets 25 and 27 which are sealed by an O-ring 94 at the junction with each other.

The bottom plate 83 is secured to the bottom of the casing 27 by means of fasteners 29 and sealed by means of O-rings 88, 90 and 92.

Electrical connections such as for the heating devices 86 and the coil 74 are formed via a pair of terminal blocks 96 and 98, which are again connected to an electrical line 36 which is electrically connected to the controller 32 via the line 34.

Sheaths 25 and 27 can be filled with insulating material. such as polyurethane foam or the like, to prevent heat from entering the device from outside during operation thereby reducing the amount of nitrogen evaporating from the liquid state.

From the foregoing, it will be apparent that the present invention provides a supply device for pressurizing vessels using liquid gas, wherein a liquid gas level is maintained in the device and a balance is maintained between the gaseous and the liquid gas and preventing the device from freezing during operation.

8 1 0 56 70 ___

Claims (9)

Barrel pressurizing device characterized in that it comprises a source (10) of liquid gas. present, means (20) for adjusting the pressure in the source of the liquid gas, means (28) for detecting vessels (26) and an injector (24) which responds to the detection means and which is communicates with the liquid gas source for supplying liquid gas to the vessels. 2. Device according to claim 1, characterized in that means (32) for determining a period of time are provided for controlling the amount of liquid gas supplied to the vessels (26), Device according to claim 1 or 2, characterized in that a heating device (18) is placed between the liquid gas source and the means for controlling the pressure. Device according to claim 1, 2 or 3, characterized in that the injector (24) comprises a chamber (42) for liquid gas, injection means (82) connected to the chamber and a float (46) for controlling the level of the liquid gas and the gas pressure in the injector. Device according to claim 4, characterized in that a shut-off valve (78) is provided which is connected to the chamber (42) for flowing the liquid gas to the vessels (26) and in that means (32, 74) be present for controlling that valve. Device according to claim 4 or 5, characterized in that the float (46) has a lid (48) with openings (50) and a valve (56) for allowing gas to escape from the chamber ( 42) 7. Device as claimed in claim 5, characterized in that the means for controlling liquid gas evacuation valve means comprise a coil (74) and a spring (75). Device according to one or more of claims 5 to 7, characterized in that the heating device (26) is placed inside a bottom plate (83) of the device for preventing the device from freezing during the operation. Device according to any one of claims 5 to 8, characterized in that the heating device (73) is provided for preventing the formation of liquid in the device when it is out of operation. 8105670