GAS EXTRACTION DEVICE AND GAS EXTRACTION METHOD FOR REFRIGERATOR

- UNION INDUSTRY CO., LTD.

A gas extraction device installed in a refrigerator removes uncondensed gases that exist in the refrigerator. The gas extraction device includes a gas extraction tank used to circulate a refrigerant put in an evaporator, a circulation pipe for circulation between the gas extraction tank and the evaporator, a gas extraction pump which feeds the refrigerant in the evaporator to the gas extraction tank, a shutoff valve configured to shut off a flow of the refrigerant from the gas extraction tank to the evaporator, a gas extractor which extracts the uncondensed gas in the refrigerator into the gas extraction tank, and an auxiliary tank which receives an inflow of the refrigerant filling up the gas extraction tank, and overflowing therefrom.

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
FIELD OF THE INVENTION

The present invention relates to a gas extraction device and a gas extraction method for removing uncondensed gases that exist in a refrigerator.

BACKGROUND OF THE INVENTION

In conventional refrigerators, for example, adsorption type refrigerators and absorption type refrigerators, a refrigerant is put in a container such as a vacuumized evaporator and the condenser, and heat of evaporation generated when evaporating the refrigerant in the evaporator is used to produce cold water. The containers of these refrigerators are injected with the refrigerant and then vacuumized before shipment.

Over a long-term use of such a refrigerator, traces of air infiltrating through sealed sections of the container or pipes, or hydrogen associated with internal corrosion is generated, and air and hydrogen, which are uncondensed gases, are accumulated in the container. These uncondensed gases that reside in the container, adversely interfere with evaporation and condensation of the refrigerant, resulting in deterioration of the refrigerator performance. To avoid that, variously designed gas extraction devices have been used to draw and discharge these uncondensed gases from the container.

The Patent document 1 discloses an absorption type refrigerator including a gas extraction device which evacuates air from inside of the absorption type refrigerator, a gas extraction tank used for storage of the gasses extracted by the gas extraction device, and a palladium cell for discharging the gasses stored in the gas extraction tank out of the refrigerator. In the absorption type refrigerator, the air-impermeable palladium cell having a hydrogen-permeability at certain temperatures is used to discharge the hydrogen out of the refrigerator.

It is disclosed in the Patent document 2 that when an absorbing solution, such as a lithium bromide solution, is supplied from an absorber to a regenerator by a solution pump, the uncondensed gases in the absorber are drawn into a liquid-vapor separator to be discharged by a down-flow gas extraction device.

PRIOR ART DOCUMENT Patent Document

Patent document 1: JP-A Publication No. 2002-295929

Patent document 2: JP-A Publication No. 05-264132

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

According to the disclosures of the Patent documents 1 and 2, the uncondensed gases in vapor phase and the solution in liquid phase are separated from each other simply by liquid-vapor separation in the liquid-vapor separator or gas extraction tank. Therefore, a device resistant to atmospheric pressure, such as a water ejector or a vacuum pump, is additionally necessary after the liquid-vapor separation to discharge the uncondensed gases remaining in the liquid-vapor separator or the gas extraction tank, such as air, into atmosphere.

The present invention was accomplished to solve these conventional technical problems. The present invention provides a gas extraction device and a gas extraction method for refrigerator configured to prevent uncondensed gases, such as air and hydrogen, from accumulating in a gas extraction tank and further adapted to prevent the uncondensed gases and outside air from flowing into a refrigerator.

Means for Solving Problems

An aspect of the present invention provides a gas extraction device for a refrigerator, which is installed in the refrigerator configured to produce cold water using heat of evaporation generated when evaporating a refrigerant put in a vacuumized evaporator, the gas extraction device for removing an uncondensed gas that exists in the refrigerator including:

a gas extraction tank for circulating the refrigerant in the evaporator;

a circulation pipe for circulation between the gas extraction tank and the evaporator;

a gas extraction pump installed in the circulation pipe to feed the refrigerant in the evaporator to the gas extraction tank;

a shutoff valve installed in the circulation pipe so as to shut off a flow of the refrigerant from the gas extraction tank to the evaporator;

a gas extractor for extracting the uncondensed gas in the refrigerator into the gas extraction tank using the refrigerant supplied from the evaporator to the gas extraction tank; and

an auxiliary tank connected to an upper section of the gas extraction tank and receives an inflow of the refrigerant filling up the gas extraction tank, and overflowing therefrom.

Another aspect of the present invention provides a gas extraction method for a refrigerator using the above-configured gas extraction device for the refrigerator, the method including:

gas extraction step of opening the shutoff valve accompanied with an operation of the gas extraction pump, circulating the refrigerant in the evaporator to the gas extraction tank, and drawing the uncondensed gas in the refrigerator into the gas extraction tank using the gas extractor; and

discharging step of closing the shutoff valve accompanied with the operation of the gas extraction pump, filling up the gas extraction tank with the refrigerant put in the evaporator so as to be overflowed into the auxiliary tank, and discharging the uncondensed gases drawn and stored in the gas extraction tank into the auxiliary tank.

Effect of the Invention

The gas extraction device for refrigerator employs the gas extraction pump and the gas extractor so that the refrigerant in the evaporator is supplied to the gas extraction tank by the gas extraction pump, and the uncondensed gases in the refrigerator are extracted into the gas extraction tank. After the uncondensed gases are extracted into the gas extraction tank, the shutoff valve is closed and the gas extraction pump is operated. Then, the refrigerant supplied to the gas extraction tank by the gas extraction pump fills up the gas extraction tank and then overflows into the auxiliary tank.

Accordingly, all the uncondensed gases extracted into the gas extraction tank, such as air and hydrogen, are fully discharged into the auxiliary tank. Finally, the uncondensed gases are finally discharged from the auxiliary tank out of the refrigerator into atmosphere.

Thus, the gas extraction device prevents the uncondensed gases from residing in the gas extraction tank.

Therefore, it is unnecessary to additionally provide a device, such as a water ejector or a vacuum pump, to discharge the uncondensed gases remaining in the vacuumized gas extraction tank (at an internal pressure lower than atmospheric pressure) into atmosphere. Further, the gas extraction tank filled with the refrigerant leaves no space for the uncondensed gases. This eliminates the possibility of backflow of the uncondensed gases and outside air into the refrigerator when the uncondensed gases are extracted by the gas extraction pump and the gas extractor.

The gas extraction device for refrigerator prevents the uncondensed gases, such as air and hydrogen, from remaining in the gas extraction tank and further prevents the uncondensed gases and outside air from flowing back into the refrigerator.

The gas extraction method for refrigerator, by performing the gas extraction step and the discharging step, prevents the uncondensed gases, such as air and hydrogen, from remaining in the gas extraction tank and further prevent the uncondensed gases from flowing back into the refrigerator.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an illustration of a gas extraction device that performs a gas extracting operation (gas extraction step) according to an embodiment of the present invention.

FIG. 2 is an illustration of a gas extraction device that performs a filling operation (filling step) according to the embodiment.

FIG. 3 is an illustration of a gas extraction device according to the embodiment when operating a refrigerator.

FIG. 4 is an illustration of a refrigerator according to the embodiment, which is operated using a first adsorbing/desorbing device functioning as an adsorbing device and a second adsorbing/desorbing device functioning as a desorbing device.

FIG. 5 is an illustration of a refrigerator according to the embodiment, which is operated using a first adsorbing/desorbing device functioning as the desorbing device and a second adsorbing/desorbing device functioning as the adsorbing device.

FIG. 6 is a flowchart illustrating a gas extraction method for refrigerator according to the embodiment.

FIG. 7 is an illustration of another gas extraction device according to the embodiment.

 MODES FOR CARRYING OUT THE INVENTION

Preferred mode of the gas extraction device and the gas extraction method for refrigerator as above will be described below.

The refrigerator may be formed as an adsorption type refrigerator in which refrigerant vapor is repeatedly adsorbed to and desorbed from a solid adsorbent by an adsorbing device and a desorbing device to circulate the refrigerant between an evaporator and a condenser, so that cold water is produced in an evaporator pipe provided in the evaporator so as to penetrate therethrough. The refrigerator may be an absorption type refrigerator in which a refrigerant is circulated between a condenser and an evaporator by the use of an absorbing solution which absorbs refrigerant vapor, so that cold water is produced in an evaporator pipe provided in the evaporator so as to penetrate therethrough.

The gas extractor may be an ejector configured to draw in gas using a liquid flow. The gas extractor is allowed to extract the uncondensed gases from the refrigerator at a portion where the uncondensed gases are most likely to accumulate. The condenser of the adsorption type refrigerator may be subjected to the gas extraction, and the absorber device of the absorption type refrigerator may be subjected to the gas extraction, for example.

Preferably, the gas extraction tank includes a first liquid level gauge which outputs a water-level signal when a liquid level of the refrigerant in the gas extraction tank becomes the same as or lower than a predefined height;

the auxiliary tank includes a second liquid level gauge which outputs a water-level signal when a liquid level of the refrigerant in the auxiliary tank becomes the same as or higher than a predefined height; and

a controller of the gas extraction device is configured to perform a gas extraction operation by opening the shutoff valve, and continuously operating the gas extraction pump until reception of the water-level signal output from the first liquid level gauge, and a filling operation by closing the shutoff valve, and continuously operating the gas extraction pump until reception of the water-level signal output from the second liquid level gauge.

In this case, the use of the first liquid level gauge enables proper management of a duration of the gas extraction performed by the gas extraction pump, and the use of the second liquid level gauge enables proper discharge of the uncondensed gases from the gas extraction tank into the auxiliary tank, and easy prevention of the refrigerant overflow from the auxiliary tank.

The duration of the gas extraction performed by the gas extraction pump may be set to a length of time suitably determined without using the first liquid level gauge.

Preferably, the circulation pipe includes a feed pipe connected to a lower section of the evaporator and equipped with the gas extraction pump, and a return pipe connected to a lower section of the gas extraction tank and equipped with the shutoff valve; and

end portions of the feed pipe and the return pipe that are open to the gas extraction tank are positioned lower than the height of the liquid level of the refrigerant, which is established upon output of the water-level signal from the first liquid level gauge.

This may prevent the uncondensed gases extracted into the gas extraction tank from accidentally flowing into the return pipe and being mixed therein. This may further prevent the uncondensed gases extracted into the gas extraction tank from accidentally flowing back into the feed pipe.

Preferably, a first tank valve is provided between the gas extraction tank and the auxiliary tank;

a second tank valve is provided above the auxiliary tank; and

the controller is configured to close the first tank valve when performing the gas extraction operation, open the first tank valve and the second tank valve when performing the filling operation, and close the first tank valve when receiving the water-level signal output from the second liquid level gauge.

In this case, upon the gas extraction, the first tank valve is closed so as to prevent outside air from being mixed into the gas extraction tank by way of the auxiliary tank. After the filling operation, the first tank valve is closed so as to prevent the uncondensed gases, such as air and hydrogen, from being mixed into the gas extraction tank again by way of the auxiliary tank.

Preferably, an upper section of the gas extraction tank has a shape with a horizontal sectional area that becomes smaller toward an upward direction; and

the auxiliary tank is connected to a portion at the upper section of the gas extraction tank, which has a minimum horizontal sectional area.

This may prevent a part of the uncondensed gases constituting a vapor phase component in the gas extraction tank from remaining in corners at the upper section of the gas extraction tank when the refrigerant filled in the gas extraction tank overflows into the auxiliary tank. As a result, all the uncondensed gases in the gas extraction tank are fully discharged into the auxiliary tank.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of a gas extraction device for a refrigerator is described in detail referring to the accompanied drawings.

As illustrated in FIGS. 1 to 3, a gas extraction device 5 for a refrigerator 1 according to the embodiment is installed in the refrigerator 1 that produces a cold water W by using heat of evaporation generated upon evaporation of a refrigerant A put in a vacuumized evaporator 31.

The gas extraction device 5 is provided with a gas extraction tank 61, a circulation pipe 8, a gas extraction pump 71, a shutoff valve 72, a gas extractor 73, and an auxiliary tank 62.

The gas extraction tank 61 has a container shape and is used to circulate the refrigerant A in the evaporator 31. The circulation pipe 8 is connected to the gas extraction tank 61 and the evaporator 31 for circulation therebetween. The gas extraction pump 71 is installed in the circulation pipe 8 and used to feed the refrigerant A from the evaporator 31 to the gas extraction tank 61. The shutoff valve 72 is installed in the circulation pipe 8 and capable of blocking a flow of the refrigerant A from the gas extraction tank 61 to the evaporator 31. The gas extractor 73 extracts the uncondensed gases G in the refrigerator 1 into the gas extraction tank 61 using the refrigerant A supplied from the evaporator 31 to the gas extraction tank 61. The auxiliary tank 62 is connected to an upper section of the gas extraction tank 61 to cause the refrigerant A that is filled and overflows from the gas extraction tank 61 to inflow.

The gas extraction device 5 of the refrigerator 1 and a gas extraction method according to the embodiment will be hereinafter described in detail referring to FIGS. 1 to 7.

First, the refrigerator 1 according to the embodiment will be described.

FIGS. 4 and 5 are illustrations of the refrigerator 1. FIG. 5 illustrates that an adsorbing device X1 and a desorbing device X2 of the refrigerator shown in FIG. 4 are switched.

As illustrated in these drawings, the refrigerator 1 according to the embodiment is an adsorption type refrigerator 1 in which vapor of the refrigerant A is repeatedly adsorbed to and desorbed from a solid adsorbent 211 by the adsorbing device X1 and the desorbing device X2 to circulate the refrigerant A between an evaporator 31 and a condenser 32 so that the cold water W is produced in an evaporator pipe 311 that is inserted into the evaporator 31.

The adsorption type refrigerator 1 has a plurality of (two in the embodiment) adsorbing/desorbing devices 2A and 2B each having a heat transfer pipe 21 inserted therethrough, a surface of which is applied with the solid adsorbent 211, the evaporator 31 configured to communicate with the plurality of adsorbing/desorbing devices 2A and 2B individually, and the condenser 32 configured to communicate with the plurality of adsorbing/desorbing devices 2A and 2B individually.

The adsorbing/desorbing devices 2A and 2B, the evaporator 31, and the condenser 32 are configured to allow circulation of the refrigerant A (may be called refrigerant vapor A). The internal spaces of the adsorbing/desorbing devices 2A and 2B, the evaporator 31, and the condenser 32 are vacuumized to allow easy evaporation of the refrigerant A. The evaporator 31 has an internal pressure equal to about 1/100 of atmospheric pressure, and the condenser 32 has an internal pressure equal to about 1/20 of atmospheric pressure. According to the embodiment, the solid adsorbent 211 is silica gel, and the refrigerant A is water.

There are communication paths 33 for the refrigerant vapor A to pass through between the adsorbing/desorbing devices 2A and 2B, and the evaporator 31, and between the adsorbing/desorbing devices 2A and 2B, and the condenser 32. The communication paths 33 respectively have dampers 34 placed therein, which open and close the communication paths 33 under their own weights and a pressure of the refrigerant vapor A.

As illustrated in FIGS. 4 and 5, the heat transfer pipes 21 of the adsorbing/desorbing devices 2A and 2B are installed up to the region where two selector valve devices 46A and 46B are provided. The selective valve devices 46A and 46B switchably select between a cooling water C and a warm water H to be circulated in the respective heat transfer pipes 21.

The evaporator pipe 311 is inserted into the evaporator 31 as a passage of the cold water W. The evaporator pipe 311 is connected to a cold water tank 44. The evaporator pipe 311 is connected to a refrigerating device 45 to be cooled with supplied cold water W. The refrigerating device 45 may be exemplified by an air conditioning system and a refrigerator, for example. The evaporator pipe 311 is arranged to circulate through the evaporator 31, cold water tank 44, and refrigerating device 45.

A condenser pipe 321 is inserted into the condenser 32 as a passage of the cooling water C. The condenser pipe 321 is connected to a cooling water tank 41. The cooling water C from the cooling water tank 41 is circulated to the condenser pipe 321 by way of the selector valve device 46A, heat transfer pipes 21 of the adsorbing/desorbing devices 2A and 2B, and the selector valve device 46B, and then returns to the cooling water tank 41 from the condenser pipe 321.

The condenser 32 has a tray 35 for receiving the refrigerant A (water in the embodiment) condensed and liquefied by the condenser pipe 321. There is a circulation pipe 36 between the tray 35 and the evaporator 31 to feed the refrigerant A accumulated on the tray 35 to a surface of the evaporator pipe 311 in the evaporator 31.

The warm water H supplied to the heat transfer pipes 21 of the adsorbing/desorbing devices 2A and 2B is heated by exhaust heat discharged from a heat generator 42 to generate heat. The heat generator 42 may be exemplified by a solar energy assisted system, a gas engine system, a boiler, or a device configured to discharge vapor drain. The warm water H is obtained by the use of exhaust heat discharged from the heat generator 42 and stored in a warm water tank 43, and then circulated to inlets of the heat transfer pipe 21 of the adsorbing/desorbing devices 2A and 2B via the selector valve device 46A. The warm water H is further circulated from outlets of the heat transfer pipe 21 of the adsorbing/desorbing devices 2A and 2B to the heat generator 42 via the selector valve device 46B.

The cooling water C is water at 25° C. to 35° C. (about 30° C.), and the warm water H is water heated to 70° C. to 90° C. (about 80° C.). The cold water W in the evaporator pipe 311 in the evaporator 31 is cooled down to 9 to 14° C. (about 11° C.).

The adsorption type refrigerator 1 is configured to be operated by switching between the adsorbing/desorbing device 2A (or 2B) functioning as the adsorbing device X1 by circulating the cooling water C to the heat transfer pipe 21 and the adsorbing/desorbing device 2B (or 2A) functioning as the desorbing device X2 by circulating the warm water H to the heat transfer pipe 21 at given time intervals to cool the cold water W in the evaporator pipe 311 inserted into the evaporator 31. The adsorption type refrigerator 1 continuously supplies the produced cold water W from the cold water tank 44 to the refrigerating device 45.

The operation of the adsorption type refrigerator 1 will be hereinafter described.

As illustrated in FIG. 4, the first adsorbing/desorbing device 2A functions as the adsorbing device X1 when the cooling water C is supplied to the heat transfer pipe 21 in the first adsorbing/desorbing device 2A. The solid adsorbent 211 applied to the surface of the heat transfer pipe 21 in the first adsorbing/desorbing device 2A is cooled down, and the refrigerant vapor A is adsorbed to the solid adsorbent 211 by adsorption reaction. Then, an internal pressure of the first adsorbing/desorbing device 2A reduces to a lower pressure level than the internal pressures of the evaporator 31 and the condenser 32. Affected by the thus generated pressure difference, the damper 34 disposed in the communication path 33 between the first adsorbing/desorbing device 2A and the evaporator 31 is opened, while the damper 34 disposed in the communication path 33 between the first adsorbing/desorbing device 2A and the condenser 32 is closed. Then, the refrigerant vapor A in the evaporator 31 flows into the first adsorbing/desorbing device 2A and removes heat of evaporation from the surface of the evaporator pipe 311 in the evaporator 31, thus cooling down the cold water W in the evaporator pipe 311.

As illustrated in the drawing, when the cooling water C is supplied to the heat transfer pipe 21 in the first adsorbing/desorbing device 2A, the warm water H is supplied to the heat transfer pipe 21 in the second adsorbing/desorbing device 2B. The second adsorbing/desorbing device 2B supplied with the warm water H in the heat transfer pipe 21 functions as the desorbing device X2. The solid adsorbent 211 applied to the surface of the heat transfer pipe 21 in the second adsorbing/desorbing device 2B is heated, and the refrigerant vapor A is thus desorbed from the solid adsorbent 211 by desorption reaction. Then, an internal pressure of the second adsorbing/desorbing device 2B is elevated to a higher pressure level than the internal pressures of the evaporator 31 and the condenser 32. Affected by the thus generated pressure difference, the damper 34 disposed in the communication path 33 between the second adsorbing/desorbing device 2B and the evaporator 31 is closed, while the damper 34 disposed in the communication path 33 between the second adsorbing/desorbing device 2B and the condenser 32 is opened. Then, the refrigerant vapor A in the second adsorbing/desorbing device 2B flows into the condenser 32, and the refrigerant vapor A is condensed by the cooling water C running in the condenser pipe 321 of the condenser 32. The condensed refrigerant vapor A is circulated into the evaporator 31 through the circulation pipe 36.

When an amount of the refrigerant vapor A adsorbed to the solid adsorbent 211 in the first adsorbing/desorbing device 2A functioning as the adsorbing device X1 is about to reach a saturation amount, the two selector valve devices 46A and 46B are manipulated as illustrated in FIG. 5 to circulate the warm water H to the heat transfer pipe 21 in the first adsorbing/desorbing device 2A, and circulate the cooling water C to the heat transfer pipe 21 in the second adsorbing/desorbing device 2B. Then, the function of the first adsorbing/desorbing device 2A is switched to the desorbing device X2, while switching the function of the second adsorbing/desorbing device 2B to the adsorbing device X1. Accordingly, the second adsorbing/desorbing device 2B functions as the adsorbing device X1, and the first adsorbing/desorbing device 2A functions as the desorbing device X2 as described above.

Thereafter, supply of the cooling water C and the warm water H to the heat transfer pipe 21 in the first adsorbing/desorbing device 2A and the heat transfer pipe 21 in the second adsorbing/desorbing device 2B is switched in turn at given time intervals. Accordingly, two adsorbing/desorbing devices 2A and 2B are switchably used as the adsorbing device X1 and the desorbing device X2 in turn at given time intervals, so that the cold water W generated in the evaporator pipe 311 is continuously supplied to the refrigerating device 45 via the cold water tank 44.

Next, the gas extraction device 5 will be described.

FIGS. 1 to 3 illustrate a structure of the gas extraction device 5. FIG. 1 is an illustration of the gas extraction device performing a gas extracting operation (gas extraction step). FIG. 2 is an illustration of the gas extraction device performing a filling operation (filling step). FIG. 3 is an illustration of the gas extraction device when operating the refrigerator 1. These drawings illustrate the evaporator 31 alone, while omitting any other devices of the refrigerator 1. A gas extraction pipe 322, which will be described later, is connected to inside of the condenser 32 of the refrigerator 1. In these drawings, the currently active pumps 314 and 71 and opened valves 611, 621, 72, 83, 84, and 86 are illustrated in white. Meanwhile, currently inactive pumps 314 and 71, and the closed valves 611, 621, 72, 83, 84, and 86 are illustrated in black.

As illustrated in FIG. 3, the liquefied refrigerant A is contained in the evaporator 31. The evaporator 31 is provided with a refrigerant drip-feed pipe 312 configured to drip the liquefied refrigerant A as a liquid phase component in a lower section, into a vapor phase in an upper section. An upper end portion of the refrigerant drip-feed pipe 312 inserted in the evaporator 31 has a nozzle 313 through which the refrigerant A drips. A lower end portion of the refrigerant drip-feed pipe 312 has a drip-feed pump 314 which suctions the liquefied refrigerant A from the evaporator 31 and drips the suctioned liquefied refrigerant A through the nozzle 313. The drip-feed pump 314 remains active at all times so far as the refrigerator 1 which continuously produces the cold water W is operating.

As illustrated in FIGS. 1 and 2, an upper section 613 of the gas extraction tank 61 according to the embodiment has a shape where a horizontal sectional area is smaller toward upward direction. More specifically, the upper section 613 of the gas extraction tank 61 has a dome shape so that the gas extraction tank 61 becomes the highest at a horizontal center position. The upper section 613 of the gas extraction tank 61 is not necessarily limited to the dome shape but may be formed in a conical shape.

The auxiliary tank 62 is connected to a horizontal center of the upper section 613 of the gas extraction tank 61 where the horizontal sectional area is reduced to minimum as the highest position.

The circulation pipe 8 includes a feed pipe 81 connected to a lower section of the evaporator 31 and equipped with the gas extraction pump 71, and a return pipe 87 connected to a lower section of the gas extraction tank 61 and equipped with the shutoff valve 72. The feed pipe 81 according to the embodiment is bifurcated at a position downstream of the gas extraction pump 71 and then connected to the gas extraction tank 61. More specifically, the feed pipe 81 is bifurcated at a position downstream of the gas extraction pump 71 into a gas extraction pipe section 82 connected to the gas extraction tank 61 via the gas extractor 73 and a bypass pipe section 85 directly connected to the gas extraction tank 61 without passing through the gas extractor 73. The gas extraction pipe section 82 has switching valves 83 and 84 configured to open and close at upstream and downstream sides of the gas extractor 73. The bypass pipe section 85 has an opening-closing valve 86.

A first tank valve 611 configured to open and close is provided between the gas extraction tank 61 and the auxiliary tank 62, and a second tank valve 621 configured to open and close is provided above the auxiliary tank 62.

As illustrated in FIGS. 1 and 2, the gas extraction tank 61 is provided with a first liquid level gauge 612 therein, which outputs a water-level signal when a liquid level of the refrigerant A in the gas extraction tank 61 is equal to or lower than a predefined height. The first liquid level gauge 612 detects an amount of the uncondensed gases G extracted into the gas extraction tank 61 based on the height of the liquid level of the refrigerant A. The first liquid level gauge 612 may be provided at a lower position in the gas extraction tank 61. Adjustment of the position in height of the first liquid level gauge 612 allows the liquid level of the refrigerant in the gas extraction tank 61 and the amount of the uncondensed gases G to be extracted into the gas extraction tank 61 to be suitably set.

The auxiliary tank 62 is provided with a second liquid level gauge 622 therein, which outputs a water-level signal when the liquid level of the refrigerant A in the auxiliary tank 62 is equal to or higher than a predetermined height. The second liquid level gauge 622 detects an amount of the refrigerant A flowing into the auxiliary tank 62 based on the height of the liquid level of the refrigerant A. The second liquid level gauge 622 may be provided at a longitudinally intermediate position in the auxiliary tank 62. Adjustment of the position in height of the second liquid level gauge 622 allows the amount of the refrigerant A flowing into the auxiliary tank 62 to be suitably set.

An end portion 821 of the gas extraction pipe section 82 and an end portion 871 of the return pipe 87 both open to the gas extraction tank 61 are located lower than the height of the liquid-level of the refrigerant A, which are established upon output of the water-level signal from the first liquid level gauge 612. The aforementioned structure prevents the uncondensed gases G extracted into the gas extraction tank 61 from accidentally flowing into the return pipe 87 and flowing back to the feed pipe 81. The gas extraction pipe section 82 is inserted into the gas extraction tank 61 from above and provided to a position lower than the position of the first liquid level gauge 612.

As illustrated in FIGS. 1 and 2, the gas extractor 73 according to the embodiment corresponds to an ejector 73 configured to draw in gas using a liquid flow. The ejector 73 has a gas draw-in passage formed on an outer or inner side of a liquid passage. The liquid passage is connected to an intermediate position of the gas extraction pipe section 82, and the gas draw-in passage is connected to the inside of the condenser 32 of the refrigerator 1 via the gas extraction pipe 322.

The gas extraction pump 71 according to the embodiment has a higher discharge pressure than atmospheric pressure (0.1 MPa) to cause the refrigerant A filled in the gas extraction tank 61 to overflow into the auxiliary tank 62 opened under atmospheric pressure.

The refrigerator 1 according to the embodiment is controlled by a controller (control computer or control sequencer) to manipulate the two selector valve devices 46A and 46B, drip-feed pump 314, gas extraction pump 71, shutoff valve 72, first tank valve 611, second tank valve 621, and switching valves 83, 84, and 86. The water-level signals output from the first liquid level gauge 612 and the second liquid level gauge 622 are transmitted to the controller.

The controller according to the embodiment implements a gas extracting operation in which the shutoff valve 72 is opened and the first tank valve 611 and the second tank valve 621 are closed, and the gas extraction pump 71 is continuously operated until the water-level signal output from the first liquid level gauge 612 is received as illustrated in FIG. 1, and a filling operation in which the shutoff valve 72 is closed and the first tank valve 611 and the second tank valve 621 are opened, and the gas extraction pump 71 is continuously operated until the water-level signal output from the second liquid level gauge 622 is received as illustrated in FIG. 2. When the controller receives the water-level signal from the second liquid level gauge 622 during the filling operation, the controller closes the first tank valve 611 and the second tank valve 621.

A method for discharging the uncondensed gases G in the refrigerator 1 using the gas extraction device 5 according to the embodiment will be described referring to a flowchart illustrated in FIG. 6.

Prior to the discharge of the uncondensed gases G, the refrigerator 1 is operated to produce the cold water W continuously in the evaporator pipe 311 of the evaporator 31. As illustrated in FIG. 3, the drip-feed pump 314 of the evaporator 31 is operated, while the gas extraction pump 71 remains inactive. The shutoff valve 72, and the switching valves 83, 84, and 86 are closed.

After the refrigerator 1 is operated over a given period of time (for example, a few days), the operation of the refrigerator 1 is stopped, and the gas extracting step is performed to extract the uncondensed gases G, such as air and hydrogen, accumulated in the refrigerator 1 as illustrated in FIG. 1. During the gas extracting operation, the drip-feed pump 314 is kept active, while stopping the operation of the refrigerator 1. The gas extraction pump 71 is operated with the first tank valve 611, second tank valve 621, and switching valve 86 of the bypass pipe section 85 are kept closed (Step S1 of FIG. 6, subsequent steps will be recited with symbols alone). Then, the shutoff valve 72 and the switching valves 83 and 84 of the gas extractor 73 are opened (S2).

The refrigerant A is circulated between the evaporator 31 and the gas extraction tank 61, and the uncondensed gases G in the condenser 32 are drawn into the gas extraction tank 61 using the refrigerant A passing through the gas extractor 73 (S3). The gas extracting operation continues until the controller receives the water-level signal from the first liquid level gauge 612 (S4). More specifically, when the uncondensed gases G are extracted into the gas extraction tank 61, the vapor phase component in the gas extraction tank 61 increases. Meanwhile, the refrigerant A as the liquid phase component reduces, thus lowering the liquid level of the refrigerant A. When the liquid level of the refrigerant A in the gas extraction tank 61 is equal to the predefined height, the first liquid level gauge 612 transmits the water-level signal to the controller. Then, the controller switches the step from the ongoing gas extracting operation to the filling operation.

In the filing step, the controller closes the shutoff valve 72 and the switching valves 83 and 84 of the gas extractor 73, while opening the first tank valve 611, second tank valve 621, and switching valve 86 of the bypass pipe section 85 (S5) to continue the operation of the gas extraction pump 71 as illustrated in FIG. 2.

The refrigerant A circulated from the evaporator 31 by the gas extraction pump 71 is continuously accumulated in the gas extraction tank 61. When the gas extraction tank 61 is filled up with the refrigerant A, the refrigerant A starts overflowing into the auxiliary tank 62 (S6). Then, the uncondensed gases G and outside air constituting the vapor phase component in the gas extraction tank 61 are forced out by the refrigerant A into the auxiliary tank 62 and then discharged from the auxiliary tank 62 into atmosphere.

Since the auxiliary tank 62 is released to atmosphere, the refrigerant A in the auxiliary tank 62 drops into the gas extraction tank 61. The uncondensed gases G and outside air are mixed both in the gas extraction tank 61 and the auxiliary tank 62.

When the liquid level of the refrigerant A in the auxiliary tank 62 reaches the predetermined height, the second liquid level gauge 622 in the auxiliary tank 62 transmits the water-level signal to the controller (S7). The controller then closes the first tank valve 611 and the second tank valve 621 (S8) and stops the operation of the gas extraction pump 71 (S9). In this way, the gas extraction device 5 successfully discharges the uncondensed gases G in the refrigerator 1 into atmosphere.

As illustrated in FIG. 3, the switching valves 83, 84, and 86 are closed and the drip-feed pump 314 is operated while having the gas extraction pump 71 inactive to restart the operation of the refrigerator 1. After the refrigerator 1 is operated over a given period of time (for example, a few days), the uncondensed gases G are similarly extracted while the refrigerator 1 is stopped.

The gas extraction tank 61 that contains the uncondensed gases G has an internal pressure higher than that of the evaporator 31. Under the resultant pressure difference therebetween, the refrigerant A that resides in the return pipe 87 is circulated into the evaporator 31.

According to the gas extraction device 5 of the refrigerator 1 and the gas extraction method in the embodiment, the refrigerant A in the evaporator 31 is supplied to the gas extraction tank 61 by the gas extraction pump 71 and the gas extractor 73 so as to extract the uncondensed gases G in the refrigerator 1 into the gas extraction tank 61 using the combination of the gas extraction pump 71 and the gas extractor 73. After the uncondensed gases G are extracted into the gas extraction tank 61, the gas extraction pump 71 is continuously operated by closing the shutoff valve 72. The refrigerant A discharged into the gas extraction tank 61 by the gas extraction pump 71 fills up the gas extraction tank 61 and starts overflowing into the auxiliary tank 62.

In this way, the gas extraction device 5 successfully discharges all the uncondensed gases G extracted into the gas extraction tank 61, such as air and hydrogen, into the auxiliary tank 62 and then discharges the uncondensed gases G from the auxiliary tank 62 into atmosphere.

This makes it possible to prevent the uncondensed gases G from residing in the gas extraction tank 61. Therefore, it is unnecessary to additionally provide a device, such as a water ejector and a vacuum pump, to discharge the uncondensed gases G remaining in the vacuumized gas extraction tank 61 (at an internal pressure lower than atmospheric pressure) into atmosphere. Further, the gas extraction tank 61 is filled up with the refrigerant A to prevent the uncondensed gasses G from remaining in the gas extraction tank 61. This may prevent backflow of the uncondensed gases G and outside air into the refrigerator 1 when extracting the uncondensed gases G are extracted by the gas extraction pump 71 and the gas extractor 73.

The gas extraction device 5 of the refrigerator 1 and the gas extraction method according to the embodiment may prevent the uncondensed gases G, such as air and hydrogen, from remaining in the gas extraction tank 61 and further prevent the uncondensed gases G and outside air from flowing back into the refrigerator 1.

The gas extraction pump 71 and the drip-feed pump 314 according to the embodiment are connected in parallel to the evaporator 31, and separately operated. As illustrated in FIG. 7, a drip-feed pump 314A and a gas extraction pump 71A are connected in series to the evaporator 31, the refrigerant drip-feed pipe 312 is connected to the nozzle 313 from the portion between the drip-feed pump 314A and the gas extraction pump 71A, and the refrigerant drip-feed pipe 312 is equipped with a switching valve 315. In this case, the switching valve 315 provided in the refrigerant drip-feed pipe 312 is opened to selectively operate the drip-feed pump 314 alone during the operation of the refrigerator 1.

To extract the uncondensed gases G, the switching valve 315 of the refrigerant drip-feed pipe 312 is closed, and the drip-feed pump 314A and the gas extraction pump 71A are both operated. Therefore, the refrigerant A in the evaporator 31 is discharged into the gas extraction tank 61 by two pumps, that is, the drip-feed pump 314A and the gas extraction pump 71A. In the case where the gas extraction pump 71A has a discharge pressure equal to or lower than atmospheric pressure (0.1 MPa), a sum of the discharge pressure of the gas extraction pump 71A and the discharge pressure of the drip-feed pump 314A may be made higher than the atmospheric pressure.

Though not illustrated in the drawings, the refrigerator 1 is not necessarily limited to the adsorption type refrigerator 1 but may be an absorption type refrigerator in which an absorbing solution which absorbs the refrigerant vapor A (lithium bromide solution) is used to circulate the refrigerant A between the condenser 32 and the evaporator 31, so that cold water is produced in the evaporator pipe inserted into the evaporator 31. The absorption type refrigerator uses an absorber device containing the absorbing solution which absorbs the refrigerant vapor A evaporated from the evaporator 31 and a regenerator device which receives the absorbing solution including the refrigerant A from the absorber device and separates the refrigerant A from the absorbing solution by heating. The refrigerant vapor A in the regenerator device flows into the condenser 32. The refrigerant vapor A is cooled down in the condenser 32 and then drops into the evaporator 31 to be used as the refrigerant A in the evaporator 31.

In the absorption type refrigerator, a similar gas extraction device 5 can be installed to work with the evaporator 31. The gas draw-in passage of the gas extractor (ejector) 73 may be connected to the absorber device where the uncondensed gases G are most likely to accumulate. The structure of the gas extraction device 5 of the absorption type refrigerator is similar to that of the gas extraction device of the adsorption type refrigerator 1 and provides a similar operational effect.

Claims

1. A gas extraction device for a refrigerator, which is installed in the refrigerator configured to produce cold water using heat of evaporation generated when evaporating a refrigerant put in a vacuumized evaporator, the gas extraction device for removing an uncondensed gas that exists in the refrigerator comprising:

a gas extraction tank for circulating the refrigerant in the evaporator;
a circulation pipe for circulation between the gas extraction tank and the evaporator;
a gas extraction pump installed in the circulation pipe to feed the refrigerant in the evaporator to the gas extraction tank;
a shutoff valve installed in the circulation pipe so as to shut off a flow of the refrigerant from the gas extraction tank to the evaporator;
a gas extractor for extracting the uncondensed gas in the refrigerator into the gas extraction tank using the refrigerant supplied from the evaporator to the gas extraction tank; and
an auxiliary tank connected to an upper section of the gas extraction tank and receives an inflow of the refrigerant filling up the gas extraction tank, and overflowing therefrom.

2. The gas extraction device for a refrigerator according to claim 1, wherein:

the gas extraction tank includes a first liquid level gauge which outputs a water-level signal when a liquid level of the refrigerant in the gas extraction tank becomes the same as or lower than a predefined height;
the auxiliary tank includes a second liquid level gauge which outputs a water-level signal when a liquid level of the refrigerant in the auxiliary tank becomes the same as or higher than a predefined height; and
a controller is provided, which is configured to perform a gas extraction operation by opening the shutoff valve, and continuously operating the gas extraction pump until reception of the water-level signal output from the first liquid level gauge, and a filling operation by closing the shutoff valve, and continuously operating the gas extraction pump until reception of the water-level signal output from the second liquid level gauge.

3. The gas extraction device for a refrigerator according to claim 2, wherein:

the circulation pipe includes a feed pipe connected to a lower section of the evaporator and equipped with the gas extraction pump, and a return pipe connected to a lower section of the gas extraction tank and equipped with the shutoff valve; and
end portions of the feed pipe and the return pipe that are open to the gas extraction tank are positioned lower than the height of the liquid level of the refrigerant, which is established upon output of the water-level signal from the first liquid level gauge.

4. The gas extraction device for a refrigerator according to claim 2, wherein:

a first tank valve is provided between the gas extraction tank and the auxiliary tank;
a second tank valve is provided above the auxiliary tank; and
the controller is configured to close the first tank valve when performing the gas extraction operation, open the first tank valve and the second tank valve when performing the filling operation, and close the first tank valve when receiving the water-level signal output from the second liquid level gauge.

5. The gas extraction device for a refrigerator according to claim 1, wherein:

an upper section of the gas extraction tank has a shape with a horizontal sectional area that becomes smaller toward an upward direction; and
the auxiliary tank is connected to a portion at the upper section of the gas extraction tank, which has a minimum horizontal sectional area.

6. A gas extraction method for a refrigerator, which uses the gas extraction device for a refrigerator according to claim 1, the method comprising:

gas extraction step of opening the shutoff valve accompanied with an operation of the gas extraction pump, circulating the refrigerant in the evaporator to the gas extraction tank, and drawing the uncondensed gas in the refrigerator into the gas extraction tank using the gas extractor; and
discharging step of closing the shutoff valve accompanied with the operation of the gas extraction pump, filling up the gas extraction tank with the refrigerant put in the evaporator so as to be overflowed into the auxiliary tank, and discharging the uncondensed gases drawn and stored in the gas extraction tank into the auxiliary tank.

7. The gas extraction device for a refrigerator according to claim 3, wherein:

a first tank valve is provided between the gas extraction tank and the auxiliary tank;
a second tank valve is provided above the auxiliary tank; and
the controller is configured to close the first tank valve when performing the gas extraction operation, open the first tank valve and the second tank valve when performing the filling operation, and close the first tank valve when receiving the water-level signal output from the second liquid level gauge.

8. The gas extraction device for a refrigerator according to claim 2, wherein:

an upper section of the gas extraction tank has a shape with a horizontal sectional area that becomes smaller toward an upward direction; and
the auxiliary tank is connected to a portion at the upper section of the gas extraction tank, which has a minimum horizontal sectional area.

9. The gas extraction device for a refrigerator according to claim 3, wherein:

an upper section of the gas extraction tank has a shape with a horizontal sectional area that becomes smaller toward an upward direction; and
the auxiliary tank is connected to a portion at the upper section of the gas extraction tank, which has a minimum horizontal sectional area.

10. The gas extraction device for a refrigerator according to claim 4, wherein:

an upper section of the gas extraction tank has a shape with a horizontal sectional area that becomes smaller toward an upward direction; and
the auxiliary tank is connected to a portion at the upper section of the gas extraction tank, which has a minimum horizontal sectional area.

11. A gas extraction method for a refrigerator, which uses the gas extraction device for a refrigerator according to claim 2, the method comprising:

gas extraction step of opening the shutoff valve accompanied with an operation of the gas extraction pump, circulating the refrigerant in the evaporator to the gas extraction tank, and drawing the uncondensed gas in the refrigerator into the gas extraction tank using the gas extractor; and
discharging step of closing the shutoff valve accompanied with the operation of the gas extraction pump, filling up the gas extraction tank with the refrigerant put in the evaporator so as to be overflowed into the auxiliary tank, and discharging the uncondensed gases drawn and stored in the gas extraction tank into the auxiliary tank.

12. A gas extraction method for a refrigerator, which uses the gas extraction device for a refrigerator according to claim 3, the method comprising:

gas extraction step of opening the shutoff valve accompanied with an operation of the gas extraction pump, circulating the refrigerant in the evaporator to the gas extraction tank, and drawing the uncondensed gas in the refrigerator into the gas extraction tank using the gas extractor; and
discharging step of closing the shutoff valve accompanied with the operation of the gas extraction pump, filling up the gas extraction tank with the refrigerant put in the evaporator so as to be overflowed into the auxiliary tank, and discharging the uncondensed gases drawn and stored in the gas extraction tank into the auxiliary tank.

13. A gas extraction method for a refrigerator, which uses the gas extraction device for a refrigerator according to claim 4, the method comprising:

gas extraction step of opening the shutoff valve accompanied with an operation of the gas extraction pump, circulating the refrigerant in the evaporator to the gas extraction tank, and drawing the uncondensed gas in the refrigerator into the gas extraction tank using the gas extractor; and
discharging step of closing the shutoff valve accompanied with the operation of the gas extraction pump, filling up the gas extraction tank with the refrigerant put in the evaporator so as to be overflowed into the auxiliary tank, and discharging the uncondensed gases drawn and stored in the gas extraction tank into the auxiliary tank.

14. A gas extraction method for a refrigerator, which uses the gas extraction device for a refrigerator according to claim 5, the method comprising:

gas extraction step of opening the shutoff valve accompanied with an operation of the gas extraction pump, circulating the refrigerant in the evaporator to the gas extraction tank, and drawing the uncondensed gas in the refrigerator into the gas extraction tank using the gas extractor; and
discharging step of closing the shutoff valve accompanied with the operation of the gas extraction pump, filling up the gas extraction tank with the refrigerant put in the evaporator so as to be overflowed into the auxiliary tank, and discharging the uncondensed gases drawn and stored in the gas extraction tank into the auxiliary tank.
Patent History
Publication number: 20130031918
Type: Application
Filed: Mar 6, 2012
Publication Date: Feb 7, 2013
Applicant: UNION INDUSTRY CO., LTD. (Toyama-city, Toyama)
Inventors: Yasuo Yonezawa (Toyama), Shingo Sawai (Toyama), Takashi Murakami (Tokyo), Norimichi Murai (Osaka), Toshiharu Shimizu (Aichi)
Application Number: 13/642,038
Classifications
Current U.S. Class: Separating Or Preventing Formation Of Undesirables (62/85); With Cleaning Means For Apparatus (62/303); Withdrawing Or Adding Refrigerant From Or To Normally Closed System (62/149)
International Classification: F25B 47/00 (20060101); F25B 45/00 (20060101);