Title of Invention

BLEEDER FOR DISCHARGING NON-CONDENSING GASES IN AN ABSORPTION- REFRIGERATOR AND EVALUATION METHOD THEREFOR

Abstract

A bleeder, for discharging non-condensing gases such as hydrogen gas generated in an absorption-refrigerator to the outside thereof, comprises a non-condensing gas tank (2) communicating with an absorption-refrigerator body (100) through a steam-liquid separator (1) and introducing non-condensing gases such as hydrogen gas generated in the refrigerator, and an oil-less vacuum pump (5) disposed communicatively in the tank for (2) discharging non-condensing gases introduced in the tank (2).

Full Text

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention concerns a bleeder for discharging non-condensing gases in an absorption-refrigerator used for cooling/heating and so on, and an evaluation method therefor. 2. Detailed Description of the Prior Art As is well known, an absorption-refrigerator is an apparatus for connecting a regenerator, a condenser, an evaporator, an absorber and so on through piping, circulating a refrigerant such as water by absorbing or releasing it with an absorbing solution, such as lithium bromide aqueous solution and so on, and for serving for cooling operation or heating operation through heat transfer. In an absorption-refrigerator of the aforementioned structure, the regenerator, condenser, evaporator, absorber and the piping connecting them are made of iron or stainless steel, and if lithium bromide aqueous solution, which contains water as refrigerant and inhibitor as an absorbing solution, is used, the absorbing solution will act upon the metal of the equipment material, which will generate hydrogen gas during the formation of anticorrosion film. Especially, during the operation, since the absorbing solution is heated up to, for example, 160°C by the regenerator, the reaction between the absorbing solution and the metal occurs easily, and a generation of hydrogen gas occurs frequently. Also, since the whole of the absorption-refrigerator is composed as a highly vacuum system, though air-tightness of the absorption-refrigerator is 1A enhanced by welding or the like, it is almost inevitable that atmospheric components penetrate from pin holes, the connecter and so on, consequently nitrogen, oxygen or other atmospheric components increase as time goes by. Hydrogen gas generated by the aforementioned mechanism, nitrogen or oxygen penetrated from the atmosphere does not condensate on the level of refrigeration in the refrigerator, and stagnates in non-solution portion of the evaporator or the absorber as their solubility into the absorbing solution is low, thus their concentration gradually increases. When the non-condensing gas concentration of hydrogen gas and so on in the refrigerator increases in this way, the evaporation of refrigerant is suppressed to lower the freezing capacity. Therefore, as shown in Fig. 3, for instance, there is a technique of attaching a palladium pipe 3 to a non-condensing gas tank 2 extended from a vapor phase section of a vapor liquid separator 1 connected to an absorption-refrigerator body 100 through an absorbing solution pipe and a vapor phase pipe, heating the palladium pipe 3 to the order of 300 to 500°C, separating it from the absorbing solution on the vapor liquid separator 1, and discharging hydrogen gas of non-condensing gases generated in the absorption-refrigerator body by passing the hydrogen gas introduced into the non-condensing gas tank 2 through the wall face of the palladium pipe 3. However, for the bleeder shown in Fig. 3, the palladium pipe 3 requires to be heated up to 300 to 500°C at all times, In addition, non-condensing gas that can be discharged through the palladium pipe 3 is nothing but the hydrogen gas, and nitrogen gas, oxygen gas or other atmospheric components penetrating from 2 a pin hole in a welded portion or a connecter, and cannot be discharged, which is problematic. Besides, as shown in Fig. 4, there is a technique of connecting a vacuum pump 5X to the non-condensing gas tank 2 through an electromagnetic on-off valve 4, 4, and operating the vacuum pump 5X for opening the electromagnetic on-off valve 4 for discharging non-condensing gases introduced into the non-condensing gas tank 2, when the pressure sensor 6 mounted on the non-condensing gas tank 2 detects a specified pressure. However, since the bleeder shown in Fig. 4 uses an oil-seal-type vacuum pump 5X, it is necessary to monitor the oil all the time to avoid oil shortage and to lubricate properly. In addition, when stopping the vacuum pump 5X by closing the electromagnetic on-off valve 4, if an on-off valve 4X is not opened to put the atmospheric pressure on the admission side, gas leakage may occur in the electromagnetic on-off valve 4 or the piping, or oil of the vacuum pump 5X flows backward, due to the temperature change, or other problems occur. SUMMARY OF THE INVENTION Consequently, none of the conventional bleeders for absorption-refrigerator is satisfactory as explained; therefore, it is necessary to provide a bleeder that can securely discharge non-condensing gases generated in the absorption-refrigerator or penetrated from the exterior of the refrigerator out of the refrigerator, which would constitute problems to be resolved. 3 The present invention has been made in order to solve problems of the aforementioned prior art, and provides a bleeder for discharging non-condensing gases such as hydrogen gas generated in an absorption-refrigerator to the outside thereof; comprising a non-condensing gas tank communicating with an absorption-refrigerator body through a steam-liquid separator and introducing non-condensing gases such as hydrogen gas generated in the refrigerator, and an oil-less vacuum pump disposed to be in communication with the non-condensing gas tank for discharging non-condensing gases introduced in the non-condensing gas tank. In a preferred embodiment of the bleeder, wherein in the oil-less vacuum pump comprising a suction hood having a suction hood inlet and a suction hood outlet, an exhaust hood having an exhaust hood inlet and an exhaust hood outlet, and a cylinder having a piston extended from the suction hood outlet and the exhaust hood inlet to reciprocate, the oil-less vacuum pump is provided with a first discharging mechanism including an on-off valve for opening the suction hood outlet when the piston reverses or advances and for closing the suction hood outlet when the piston advances or reverses at the suction hood outlet, and an on-off valve for closing the suction hood outlet when the piston reverses or advances and for opening the suction hood outlet when the piston advances or reverses at the exhaust hood inlet, and a second discharging mechanism, identical to the first discharging mechanism, making a suction hood inlet thereof communicate with the exhaust hood outlet of the first discharging mechanism: 4 and both pistons of the first discharging mechanism and the second discharging mechanism reciprocate in the opposite direction from each other. This invention also provides an evaluation method of the bleeder for evaluating the degree of deterioration, including failure of the vacuum pump or gas leakage from a piping based on pressure variation at upstream side of the vacuum pump during the start or operation of the vacuum pump, in the aforementioned bleeder to solve problems of the prior art. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS These and other advantages of the present invention will become clear from following description with reference to the accompanying drawings, wherein : Fig. 1 is an illustrative drawing showing one embodiment of the present invention ; Fig. 2 is an illustrative drawing showing an oil-less vacuum pump used for the one embodiment; Fig. 3 is an illustrative drawing showing the conventional technology ; and Fig. 4 is an illustrative drawing showing another conventional technology. Description of Symbols 1. Vapor liquid separator 2. Non-condensing gas tank 3. Palladium pipe 4. Electromagnetic on-off valve 5 5. 5X. Vacuum pump 6. Pressure sensor 7. Bleeding pipe 7A. Heat radiating coil 7Z. Bleeding pipe 8. Vapor liquid separator box 9. Drain pipe 9A. On-off valve 10. First discharging mechanism 11. Suction hood inlet 12. On-off valve 13. Suction hood outlet 14. Suction hood 15. Exhaust hood outlet 16. On-off valve 17. Exhaust hood inlet 5A 18 Exhaust hood 19 Piston 20 Cylinder 21 Space in cylinder 30 Second discharging mechanism 31 Suction hood inlet 32 On-off valve 33 Suction hood outlet 34 Suction hood 35 Exhaust hood outlet 36 On-off valve 37 Exhaust hood inlet 38 Exhaust hood 39 Piston 40 Cylinder 41 Space in cylinder 50 Motor 51L, 51R Driving shaft 52L, 52R Crank 60 Controller 61 Alarm device 100 Absorption-refrigerator DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT While the presently preferred embodiment of the present invention has been shown and described, it will be understood that the present invention is not limited thereto, and that various changes and modification may be made by those skilled 6 in the art without departing from the scope of the invention hereinafter claimed. Now, the bleeder of the present invention shall be described in detail based on Fig. 1 and 2. It should be noted that, in order to facilitate the comprehension, in these drawings as well, the parts having the functions similar to those described for the aforementioned Figs. 3 and 4 are indicated by the same symbol. In the bleeder of the present invention shown in Fig. 1, an oil-less-type vacuum pump 5 is connected in communication with a non-condensing gas tank 2 through a vapor liquid separator box 8 and so on. Besides, a bleeding pipe 7, provided with two electromagnetic on-off valves 4 in series, has a radiator coil 7A disposed on the side of the vapor liquid separator box 8, and a terminal portion opened to the vapor liquid separator box 8. It should be noted that a drain pipe 9, in which an on-off valve 9A is interposed, is connected to a bottom plate of the vapor liquid separator box 8, and is composed to properly discharge refrigerant liquid or the like accumulated inside the vapor liquid separator box 8 by opening the on-off valve 9A. Since the oil-less-type vacuum pump 5 is placed at the trailer of a bleeding pipe 7Z extending from a top plate section of the vapor liquid separator box 8, condensate, such as refrigerant that radiates heat into the atmosphere and is condensed during the passage through a portion of the radiator coil 7A of the bleeding pipe 7, accumulates at the bottom section in the vapor liquid 7 separator box 8, and only non-condensing gases are derived from the bleeding pipe 7Z and certainly only non-condensing gases reach the vacuum pump 5. The vacuum pump 5 is comprised of, as shown in Fig. 2 for example, the first discharging mechanism 10 and the second discharging mechanism 30. The first discharging mechanism 10 is composed of a suction hood 14 having a suction hood inlet 11 and a suction hood outlet 13 to be opened and closed by an on-off 7A valve 12, an exhaust hood 18 having an exhaust hood outlet 15 and an exhaust hood inle 17 to be opened and closed by an on-off valve 16, and a cylinder 20 having a piston 19 extended from a portion of the suction hood outlet 13 and the exhaust hood inlet 17 and reciprocating therein. It should be noted that the on-off valve 12 opens the suction hood outlet 13 when the piston 19 moves downward in the drawing, increasing the capacity of the space 21 in the cylinder, and lowering the inner pressure, and closes the suction hood outlet 13 when the piston 19 moves upward in the drawing, reducing the capacity of the space 21 in the cylinder, and increasing the inner pressure. On the other hand, the on-off valve 16 closes the exhaust hood inlet 17 when the piston 19 moves downward in the drawing, increasing the capacity of the space 21 in the cylinder, and lowering the inner pressure, and opens the exhaust hood inlet 17 when the piston 19 moves upward in the drawing, reducing the capacity of the space 21 in the cylinder, and increasing the inner pressure. The second discharging mechanism 30 is composed of a cylinder 40 provided with a suction hood 34 having a suction hood inlet 33 to be opened and closed by an on-off valve 32, an exhaust hood 38 having an exhaust hood outlet 35 and an exhaust hood inlet 37 to be opened and closed by an on-off valve 36, and a piston extended from the portion of suction hood outlet 33 and exhaust hood inlet 37 and reciprocating. It should be noted that the on-off valve 32 is also composed to open the suction hood outlet 33 when the piston 39 moves downward in the drawing, increasing the capacity of the space 41 in the cylinder, and lowering the inner pressure, and to close the suction hood outlet 33 when the piston 39 moves upward in the drawing, reducing the capacity of the space 41 in the cylinder, and increasing the inner pressure. On the other hand, the on-off valve 36 is installed to close the exhaust hood inlet 37 when the piston 39 moves downward in the 8 drawing, increasing the capacity of the space 41 in the cylinder, and lowering the inner pressure, and to open the exhaust hood inlet 37 when the piston 39 moves upward in the drawing, reducing the capacity of the space 41 in the cylinder, and increasing the inner pressure. There, the piston 19 of the first discharging mechanism 10 is connected to a rotation shaft 51L of a motor 50 through a crank 52L, while the piston 39 of the second discharging mechanism 30 is connected to a rotation shaft 51R of a motor 50 through a crank 52R, so that the rotation motion of the driving shaft 51L and 51R by the motor 50 are converted into reciprocating motion of each piston 19 and 39 to reciprocate them in respective cylinder. Here, the piston 19 of the first discharging mechanism 10 and the piston 39 of the second discharging mechanism 30 are mounted to move in the opposite direction to each other. Consequently, when the piston 19 of the first discharging mechanism 10 moves downward in the drawing, the piston 39 of the second discharging mechanism 30 moves upward in the drawing, and when the piston 19 of the first discharging mechanism 10 moves upward in the drawing, the piston 39 of the second discharging mechanism 30 moves downward in the drawing. Therefore, in the first discharging mechanism 10, when the piston 19 moves downward in the drawing, increasing the capacity of the space 21 in the cylinder and lowering the inner pressure of the space 21 in the cylinder, both on-off valves 12 and 16 rotate downward in the drawing to open the suction hood outlet 13 and to close the exhaust hood inlet 17; therefore, non-condensing gases introduced into the suction hood 14 from the suction hood inlet 11 go through the suction hood outlet 13 and enter the space 21 in the cylinder. There, when the piston 19 of the first discharging mechanism 10 moves downward in the drawing, and when non-condensing gases of the suction hood 14 are introduced into the space 21 in the cylinder whose capacity has increased, the 9 piston 39 of the second discharging mechanism 30 moves upward, in the drawing, reducing the capacity of the space 41 in the cylinder, and increasing the inner pressure of the space 41 in the cylinder, and both on-off valves 32 and 36 rotate upward in the drawing to close the suction hood outlet 33 and to open the exhaust hood inlet 37. Therefore, non-condensing gases in the exhaust hood 18 of the first discharging mechanism 10, suction hood 34 of the second discharging mechanism 30, and the connecting pipe between the first discharging mechanism 10 and the second discharging mechanism 30 are not introduced into the space 41 in the cylinder, while non-condensing gases introduced into the space 41 in the cylinder are discharged from the exhaust hood inlet 37, exhaust hood 38, and exhaust hood outlet 35. On the other hand, in the first discharging mechanism 10, when the piston 19 moves upward in the drawing, reducing the capacity of the space 21 in the cylinder, and increasing the inner pressure of the space 21 in the cylinder, both on-off valves 12 and 16 rotate upward in the drawing to close the suction hood outlet 13 and to open the exhaust hood inlet 17 ; therefore, non-condensing gases which are introduced into the space 21 in the cylinder from the suction hood 14 during the above mentioned step where the piston moves downward in the drawing, go through the exhaust hood outlet 17 and enter the exhaust hood 18. 10 There, when the piston 19 of the first discharging mechanism 10 moves upward in the drawing, and non-condensing gases are pushed out from the space 21 in the cylinder into the exhaust hood 18, the piston 39 of the second discharging mechanism 30 moves downward in the drawing, increasing the capacity of the space 41 in the cylinder and reducing the inner pressure of the capacity of the space 41, both on-off valves 32 and 36 rotate upward in the drawing to open the suction hood outlet 33 and to close the exhaust hood inlet 37. Therefore, the open air would not be introduced into the space 41 in the cylinder through the exhaust hood outlet 35, exhaust hood 38, and exhaust hood inlet 37, while non-condensing gases in the exhaust hood 18 of the first discharging mechanism 10, the suction hood 34 of the second discharging mechanism 30, and the connecting pipe between the first discharging mechanism 10 and the second discharging mechanism 30 are introduced into the space 41 in the cylinder through the suction hood outlet 33. Consequently, non-condensing gases accumulated in the non-condensing gas tank 2 can be discharged by reciprocating the piston 19 and 39 in the cylinder 20 and 40 by starting the motor 50, and at the same time, opening the electromagnetic on-off valve 4. The symbol 60 indicates a controller of the bleeder, composed to control so as to start the motor 50 upon detection of a predetermined high pressure, for example, 10kPa (the set value is variable) by a pressure sensor 6 mounted on the non-condensing gas tank 2, to open the electromagnetic on-off valve 4 after 11 a predetermined period of time, for example, 10 sec (the set value is variable) after the motor 50 is started, to close the electromagnetic on-off valve 4 upon detection of a predetermined low pressure, for example, 4kPa (the set value is variable) by the pressure sensor 6, and thereafter to stop the motor 50. It should be noted that the controller 60 is composed to judge that an abnormal event, such as a serious abnormality in the bleeder, for example, dysfunction of the piston 19, 39, leakage of atmosphere (in great volume) or the like, is happening, upon detection of a pressure higher than a determined high pressure, for example, 10 kPa by a pressure sensor 6, when a predetermined period of time, for example, 2 sec (the set value is variable) has elapsed after the electromagnetic on-off valve 4 is closed, to activate an alarm device 61, to issue a warning by, for instance, sounding a buzzer, blinking an alarm lamp, or the like and, 11A at the same time, to close the electromagnetic on-off valve 4, thereafter to stop the motor, and thereafter to inhibit the bleeding operation no matter how high the pressure detected by the pressure sensor 6 is. Besides, the controller 60 is also composed to judge that the capacity of the bleeder is deteriorated when the pressure sensor 6 does not detect a predetermined low pressure, for example, a pressure of 4 kPa within a predetermined period of time, for example, within 10 min (variable) after the motor 50 is started, or the electromagnetic on-off valve 4 is opened, even if the pressure sensor 6 detects a pressure lower than 10 kPa, the controller 60 activates an alarm device 61, indicates a predetermined warning, for instance, calls attention, and continues to bleeding. Concerning the predetermined alarm device, the bleeding operation may be resumed when the pressure sensor 6 detects a predetermined pressure again, for example, 10 kPa, even if the bleeding operation is suspended once. It should be noted that the vapor liquid separator 1 of the bleeder is a conventionally well-known apparatus for injecting a part of absorbing solution to be transported to a hot regenerator and so on by an absorbing solution pump, which is not illustrated, into an ejector 1A, drawing in gases containing non-condensing gas from a vapor phase section of an absorber and so on utilizing negative pressure generated therein, and separating into absorbing solution and non-condensing gas insoluble in the absorbing solution. As a result, if the hot regenerator, cold regenerator, condenser, evaporator, absorber, higher-heat exchanger, lower-heat exchanger and the piping portions connecting them are made of, for instance, iron or stainless steel, water is used as refrigerant and lithium bromide aqueous solution and so on containing inhibitor as absorbing solution, as mentioned above, during the operation, as the absorbing solution is heated, for example, up to 160°C by the regenerator, the absorbing 12 solution will act upon the metal of the equipment material, form an anticorrosive film on the surface, and generate hydrogen gas during this formation. Thus, the hydrogen gas generated in the refrigerator does not condensate in the cooling temperature range in the absorption-refrigerator and, since its solubility to the absorbing solution is extremely low, stagnates in a non-solution section, such as absorber, increasing its concentration gradually. However, if the bleeder of the present invention is integrated in the absorption-refrigerator, refrigerant vapor, misty absorbing solution, hydrogen gas or other atmosphere existing in the gaseous phase section of an absorption-refrigerator body 100 are drawn in the vapor liquid separator 1 using negative pressure generated by a rapid displacement of a part of absorbing solution discharged by the operation of an absorbing solution pump as power, which is not shown, and separated into absorbing solution and non-condensing gases insoluble to the absorbing solution, and the absorbing solution is returned to the absorption-refrigerator body 100 from the bottom section of the vapor liquid separator 1, and the non-condensing gases separated from the absorbing solution is introduced into the non-condensing gas tank 2. When the pressure in the non-condensing gas tank 2 attains a predetermined pressure, for example, 10 kPa, the vacuum pump 5 is started by the controller 60, the electromagnetic on-off valve 4 is opened after a predetermined period of time, and the non-condensing gases accumulated in the non-condensing gas tank 2 will be discharged. 13 It should be noted that the controller 60 judges that an abnormal event, such as a serious abnormality in the bleeder, for example, dysfunction of the piston 19, 39, leakage of atmosphere in great volume or the like, is happening, upon detection of a pressure higher than a determined high pressure, for example, 10 kPa, by a pressure sensor 6, even if a predetermined period of time, for example, 2 sec, has elapsed after the electromagnetic on-off valve 4 is closed, and activates 13A the alarm device 61. Besides, the controller 60 also judges that the capacity of the vacuum pump 5 is deteriorated, when the pressure detected by the pressure sensor 6 does not drop to a predetermined low pressure, for example, 4 kPa, within a predetermined period of time, for example, 10 min operation of the motor 50, and activates the alarm device 61. It should be noted that the present invention is not limited to the aforementioned embodiment, but can be modified variously without departing from the subject matter described in the attached claims. For example, the deterioration of the capacity of the bleeder may also be judged by comparing the variation rate of the pressure detected by the pressure sensor 6 with a standard value. According to the bleeder for absorption-refrigerator of the present invention, non-condensing gases generated in the absorption-refrigerator or non-condensing gases, such as atmospheric components penetrating into the refrigerator, can be discharged securely out of the refrigerator. In addition, lubrication of other labor hours becomes unnecessary. 14 WE CLAIM : 1. A bleeder for discharging non-condensing gases such as hydrogen gas generated in an absorption-refrigerator to the outside thereof; comprising a non-condensing gas tank communicating with an absorption-refrigerator body through a steam-liquid separator and introducing non-condensing gases such as hydrogen gas generated in the refrigerator, and an oil-less vacuum pump disposed to be in communication with the non-condensing gas tank for discharging non-condensing gases introduced in the non-condensing gas tank. 2. The bleeder as claimed in claim 1, wherein in the oil-less vacuum pump comprising a suction hood having a suction hood inlet and a suction hood outlet, an exhaust hood having an exhaust hood inlet and an exhaust hood outlet, and a cylinder having a piston extended from the suction hood outlet and the exhaust hood inlet to reciprocate, the oil-less vacuum pump is provided with a first discharging mechanism comprising an on-off valve for opening the suction hood outlet when the piston reverses or advances and for closing the suction hood outlet when the piston advances or reverses at the suction hood outlet, and an on-off valve for closing the suction hood outlet when the piston reverses or advances and for opening the suction hood outlet when the piston advances or reverses at the exhaust hood inlet, and a second discharging mechanism, identical to the first discharging mechanism, making a suction hood inlet thereof communicate with the exhaust hood outlet of the first discharging mechanism ; 15 and both pistons of the first discharging mechanism and the second discharging mechanism reciprocate in the opposite direction from each other. 3. An evaluation method of a bleeder for evaluating the degree of deterioration with failure of a vacuum pump of the bleeder or gas leakage from a piping based on pressure variation at the upstream side of the vacuum pump during the start and/or the operation of the vacuum pump, in the bleeder as claimed in claim 1 or 2. 4. A bleeder for discharging non-condensing gases in an absorption refrigerator, substantially as herein described, particularly with reference to Figs. 1 and 2 of the accompanying drawings. Dated this 20th day of March, 2003. 16 A bleeder, for discharging non-condensing gases such as hydrogen gas generated in an absorption-refrigerator to the outside thereof, comprises a non-condensing gas tank (2) communicating with an absorption-refrigerator body (100) through a steam-liquid separator (1) and introducing non-condensing gases such as hydrogen gas generated in the refrigerator, and an oil-less vacuum pump (5) disposed communicatively in the tank for (2) discharging non-condensing gases introduced in the tank (2).

Documents:

00174-kol-2003-abstract.pdf

00174-kol-2003-claims.pdf

00174-kol-2003-correspondence.pdf

00174-kol-2003-description(complete).pdf

00174-kol-2003-drawings.pdf

00174-kol-2003-form-1.pdf

00174-kol-2003-form-18.pdf

00174-kol-2003-form-2.pdf

00174-kol-2003-form-3.pdf

00174-kol-2003-form-5.pdf

00174-kol-2003-g.p.a.pdf

00174-kol-2003-letters patent.pdf

00174-kol-2003-priority document others.pdf

00174-kol-2003-priority document.pdf

00174-kol-2003-reply f.e.r.pdf