JP3643761B2 - Stirling refrigerator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to Stirling refrigerators such as Stirling refrigerators that can be used for freezing and cooling in industrial fields such as food distribution, environmental testing, medical care, biotechnology industry, semiconductor manufacturing, etc., or household equipment. The present invention relates to a working gas charging / discharging device of a Stirling refrigerator.
[0002]
[Prior art]
In recent years, it has been used as a refrigeration device in place of CFCs for global environmental problems and has a wider operating temperature than conventional refrigeration equipment. Application to refrigeration equipment in all industrial fields such as liquid circulators, low temperature thermostats, thermostats, heat shock test equipment, freeze dryers, temperature characteristics test equipment, blood / cell storage equipment, cold coolers, and other various refrigeration equipment Stirling refrigerators are in the spotlight as possible refrigerators that are compact, have high coefficient of performance, and have good energy efficiency.
[0003]
FIG. 1 shows an overall schematic diagram of a Stirling refrigerator 1. In a housing 2, a compression piston is connected to crank portions 5 and 6 of a crankshaft 4 operated by a motor 3 via cross guide heads 7 and 8, respectively. The rod 9 and the expansion piston rod 10 are connected. The compression piston 11 and the expansion piston 12 reciprocate in the compression cylinder 13 and the expansion cylinder 14 with a phase difference through the compression piston rod 9 and the expansion piston rod 10, respectively, thereby compressing and expanding the working gas. A heat exchanger for heat dissipation (high temperature side heat exchanger) disposed between a high temperature chamber (compression chamber) 15 of the compression cylinder 13 and a low temperature chamber (expansion chamber) 16 of the expansion cylinder 14 via a regenerator 17. 18 and a heat exchanger for cooling (low temperature side heat exchanger) 19 perform heat exchange between the heat-dissipating refrigerant and the cold refrigerant and the working gas, respectively.
[0004]
By the way, there is a problem that oil or oil mist rises from the crank chamber along the piston rods 9 and 10, that is, so-called oil rise. This oil rise adheres to the inner surface of oil and oil mist when entering the compression cylinder and expansion cylinder, and is carbonized by heat, thereby significantly reducing the performance and durability of the Stirling refrigerator. Conventionally, the compression piston rod 9 and the expansion piston rod 10 are sealed by oil seals 20 and 21 in order to solve the problem of oil rising.
[0005]
This oil seal has been developed in various ways in terms of structure and material, but it is not necessarily sufficient in terms of sealing performance and durability, and roll socks type sealing systems have also been proposed, but durability The current situation is not enough.
[0006]
When the Stirling refrigerator is operating, the temperature of the crank chamber 26 rises and the internal pressure rises. This increase in the pressure in the crank chamber causes a mechanical burden on the oil seal and causes deterioration, and the pressure increases the oil increase, which adversely affects performance. In addition, the reciprocating motion of the compression piston and the expansion piston causes a pressure fluctuation on the back side thereof, which has a problem of adversely affecting the oil seal.
[0007]
The present inventors aim to solve the problems inherent to the above Stirling refrigerator, and are equipped with an oil seal bellows for a piston rod that prevents oil rising and has a long service life. Absorbs pressure differences and pressure fluctuations between the crank chamber and the space behind the compression piston and expansion piston (this space is referred to as the “working space” in this specification), which is the cause of deterioration and destruction A Stirling refrigerator equipped with a buffer tank that has been developed has been filed (see Japanese Patent Application No. 10-365371).
[0008]
[Problems to be solved by the invention]
However, in the Stirling refrigerator, even when a configuration in which the crank chamber and the working space are equal to each other is adopted, when the working gas is supplied and sealed from the outside, or when the working gas is discharged Depending on the method of injection or discharge, a pressure difference will occur. If a pressure difference is generated at the time of filling and discharging such a working gas, even if the pressure is adjusted by providing the buffer tank as described above, a sufficient effect is not produced.
[0009]
An object of the present invention is to solve such a conventional problem, and a specific problem thereof is that when a working gas is charged and discharged in a Stirling refrigerator equipped with an oil seal bellows. The pressure difference between the crank chamber and the working space, which is likely to occur, is prevented, and the oil seal bellows is not deteriorated or broken to prevent the oil from rising and to extend the life of the oil seal bellows. It is to improve the performance and durability of the machine.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention compresses the working gas by reciprocating the housing having a crank chamber, the compression cylinder and the expansion cylinder disposed above the crank chamber, and the compression cylinder and the expansion cylinder. An expansion piston, an expansion piston, a compression piston rod and an expansion piston rod linked to the crank in the crank chamber, and one end connected to the compression piston and the expansion piston, and the compression piston rod and the expansion piston rod, respectively. In the Stirling refrigerator provided with an oil seal disposed at the opening of the top of the crank chamber penetrating therethrough, the oil seal is fixed to the periphery of the opening, and the tip thereof is compressed. Oil seal bellows fixed to piston rod and expansion piston rod A working gas filling and discharging device for filling or discharging working gas in the working space on the back side of the compression piston and the expansion piston in the compression chamber and the expansion cylinder; Provided is a Stirling refrigerator characterized by being arranged to communicate with each other in a working space.
[0011]
It is good also as a structure which provided the buffer tank for absorbing the pressure fluctuation in the said working space, and the pressure rise in the said housing between the said housing and the said working space. And this buffer tank is good also as a structure by which the bellows for pressure adjustment is arrange | positioned in the inside.
[0012]
The working gas filling / discharging device includes a connecting pipe, a filling pipe, and an exhaust pipe for the crank chamber and the working space, respectively, and the filling pipe of the crank chamber and the filling pipe of the working space are filled. The exhaust pipe of the crank chamber and the exhaust pipe of the working space are joined to the exhaust pipe and connected to the gas exhaust port, and the charging pipe and the exhaust pipe are joined. Each of the roads has a configuration in which an aperture is provided.
[0013]
Furthermore, in order to solve the above-mentioned problems, the present invention is a portable working gas charging / discharging device for a Stirling refrigerator having a working gas filling / exhaust gas circuit for filling and discharging the working gas in the Stirling refrigerator. The working gas charging / exhaust gas circuit is provided with a pressure sensor connected to the crank chamber of the Stirling refrigerator and the compression piston of the compression cylinder and the expansion cylinder and the working space on the back side of the expansion piston. A connecting pipe and a filling pipe having an electromagnetic valve and an exhaust pipe, and the filling pipe of the crank chamber and the filling pipe of the working space merge and are connected to the filling pipe line and communicate with the working gas supply source; The exhaust pipe of the crank chamber and the exhaust pipe of the working space join together and are connected to the exhaust pipe and communicate with the exhaust port. The filling pipe and the exhaust pipe each have a throttle. , The exhaust pipe of the crank chamber provides a Stirling refrigerating machine working gas filling and discharging device, characterized by comprising sequentially disposed an oil mist separator and the filter.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings based on examples relating to Stirling refrigerators. FIG. 2 is a view showing an embodiment of a Stirling refrigerator according to the present invention. The Stirling refrigerator 22 of the embodiment is provided with an oil seal bellows to prevent oil rising and a buffer tank with a pressure adjusting bellows communicating with the crank chamber to increase the temperature of the crank chamber relative to the oil seal bellows. The structure which absorbs the pressure rise of the space in the space resulting from this, and the pressure fluctuation of the space of the back side of a compression piston and the expansion piston is employ | adopted.
[0015]
This will be described in detail. In FIG. 2, the housing 23 of the Stirling refrigerator 22 is formed of a casting, and the inside of the housing 23 is partitioned into a motor chamber 25 and a crank chamber 26 by a partition wall 24. In the crank chamber 26, a rotary reciprocating conversion mechanism 28 for converting the rotational operation of the motor 27 into a reciprocating motion is provided. The motor chamber 25 and the crank chamber 26 are closed by lids 29 and 30, respectively.
[0016]
A crankshaft 34 that penetrates the partition wall 24 and is pivotally supported by the bearings 31 and 32 is rotatably disposed in the housing 23. The motor 27 includes a stator 35 and a rotor 36, and a crankshaft 34 is coupled to an output shaft 33 of a motor fixed to the rotor 36.
[0017]
The rotary reciprocating conversion mechanism portion 28 is attached to the crank portions 37 and 38 of the crankshaft 34 extending into the crank chamber 26, connecting rods 39 and 40 connected to the crank portions 37 and 38, and the tip of the connecting rod. The cross guide heads 41 and 42 function as drive transmission means for the Stirling refrigerator 22.
[0018]
The cross guide heads 41 and 42 are disposed so as to reciprocate within the cross guide liners 43 and 44 provided on the inner wall of the cylinder of the housing 23. The crank portions 37 and 38 are formed with a phase difference so that the crank 38 moves ahead of the crank 37 when the motor 27 rotates forward. As this phase difference, a phase difference of about 90 degrees is generally adopted.
[0019]
A compression cylinder 45 and an expansion cylinder 46 are disposed above the crank chamber 26 of the housing 23 of the Stirling refrigerator 22. In the compression cylinder 45, the expansion cylinder 46, and the housing 23, for example, helium, hydrogen, nitrogen or the like is sealed as a working gas.
[0020]
The compression cylinder 45 has a compression cylinder block 47 fixed to the housing 23 with a bolt or the like, and a compression piston 48 provided with a piston ring reciprocates in the space of the compression cylinder block 47 so that the upper portion of the space Is a high-temperature chamber (compression space) 49, and the working gas therein is compressed to a high temperature.
[0021]
The compression piston rod 50 has one end fixed to the compression piston 48 and the other end rotatably connected to the cross guide head 41. The upper end of the oil seal bellows 53 is fixed to the compression piston rod 50 and the lower end thereof is fixed to the peripheral edge of the opening 51 so as to seal the opening 51 at the top of the housing 23.
[0022]
As a result, the compression cylinder 45 and the crank chamber 26 of the housing 23 are completely sealed, and oil is completely prevented from entering the compression cylinder 45 from the crank chamber 26. As the oil seal bellows 53, a metal forming bellows integrally formed by pressing a metal material or a metal welding bellows assembled by welding is used.
[0023]
Since the reciprocating compression piston 48 reverses the sliding direction at the top dead center and the bottom dead center, the speed becomes zero, and the speed is slow near the top dead center and the bottom dead center, and the amount of change in volume per unit time is also large. Small, maximum speed at each intermediate point when moving from bottom dead center to top dead center and top dead center to bottom dead center, and maximum volume change due to piston movement per unit time .
[0024]
On the other hand, the expansion cylinder 46 is positioned slightly above the compression cylinder 45 and has an expansion cylinder block 54 fixed to the housing 23 and the compression cylinder block 47 by bolts or the like. The expansion piston 55 provided with a ring slides back and forth, and the upper portion of this space is a low temperature chamber (expansion space) 56, and the working gas in the space expands to become a low temperature. The expansion piston 55 moves ahead of the compression piston 48 by a phase of about 90 degrees.
[0025]
The expansion piston rod 57 has one end fixed to the expansion piston 55 and the other end rotatably connected to the cross guide head 42. The upper end of the oil seal bellows 58 is fixed to the expansion piston rod 57 and the lower end of the oil seal bellows 58 is fixed to the periphery of the opening 52 of the housing 23 so as to seal the upper opening 52 of the housing 23.
[0026]
Thereby, the expansion cylinder 46 and the crank chamber 26 are completely sealed, and the expansion cylinder 46 and the expansion piston rod 57 are completely prevented from entering the expansion cylinder 46. For the oil seal bellows 58, the same metal forming bellows or metal welding as those for the compression cylinder is used.
[0027]
A buffer tank 59 is disposed in the Stirling refrigerator 22, and a pressure adjusting bellows 61 that extends and contracts in the axial direction is disposed in the buffer tank 59. With this pressure adjusting bellows 61, the buffer tank 59 is partitioned into a chamber 63 on the opening side of the pressure adjusting bellows 61 and a chamber 65 on the closing wall side of the pressure adjusting bellows 61.
[0028]
The chamber 63 on the opening side of the pressure adjusting bellows 61 communicates with a space 69 on the back side of the compression piston 48 of the compression cylinder by a pipe 67. A communication hole 69 ′ is formed in a partition wall between the chamber 69 and the space 70 on the back side of the expansion piston 55 of the expansion cylinder, and the two spaces 69 and 70 are communicated with each other.
[0029]
The chamber 65 on the closing wall side of the pressure adjusting bellows 61 communicates with the motor chamber 25 and the crank chamber 26 of the housing 23 by a pipe 71 (this point, the motor chamber 25 and the crank chamber 26 are separated from each other by the partition wall 24). However, they are not separated from each other in an airtight state but are in a communication state, and therefore, in this specification, it is expressed as communicating with a space in the housing 23). These pressure adjusting bellows 61 are made of metal-formed bellows, metal welded bellows, or resin or rubber bellows, like oil seal bellows 53 and 58.
[0030]
The expansion cylinder block 54 is provided with an annular manifold 73 that communicates with a high temperature chamber (compression space) 49 of the compression cylinder 45, and further includes a heat dissipation heat exchanger 74, a regenerator 75, and a cooling heat exchanger 76. They are sequentially communicated with each other and arranged in an annular shape. Near the upper end of the compression cylinder block 45, a communication hole 77 is formed. As a result, the high temperature chamber (compression space) 49 and the low temperature chamber (expansion space) 56 are connected to the communication hole 77, the manifold 73, the heat for heat dissipation. It is configured to sequentially communicate with each other via the exchanger 74, the regenerator 75, and the cooling heat exchanger 76.
[0031]
The heat dissipating heat exchanger 74 is an annular type heat exchanger, for example, a shell and tube heat exchanger (a large number of tubes through which a working gas flows in an annular heat exchanging chamber are provided in the axial direction to cool the heat. A heat exchanger that cools the working gas by flowing water into the heat exchange chamber).
[0032]
The heat dissipating heat exchanger 74 is connected to the heat dissipator 79 via the cooling water circulation pipe 78 and the cooling water pump P1, and circulates the cooling water. The cooling water heated and exchanged by the heat radiating heat exchanger 74 is cooled by the cooling fan 80 of the radiator 79. A water reservoir tank 82 is connected to the cooling water circulation pipe line 78 via a reservoir valve 81. The radiator 79 is connected with an air vent 83 and a drain valve 84.
[0033]
A cooling heat exchanger 76 is formed in the upper portion (cold head 85) of the expansion cylinder block 54. The cooling heat exchanger 76 has a working gas flow path 86 on the inner side and cooling fins formed on the outer side. The cooling heat exchanger 76 has various structures depending on the application. For example, a jacket wall may be provided at the top of the expansion cylinder block 54, and a cold refrigerant such as ethyl alcohol, HFE, PFC, PFG, nitrogen, helium may flow through the jacket wall.
[0034]
The Stirling refrigerator of the present invention is a Stirling refrigerator having a large refrigerating capacity by using two pistons of the compression cylinder 45 and the expansion cylinder 46 to increase the volume fluctuation of the space filled with the working gas of the Stirling refrigerator. 22 can be provided.
[0035]
By the way, in the Stirling refrigerator of the present invention, the oil seal bellows 53 and 58 are employed, and the buffer tank 59 is further provided to prevent the oil from rising, and the crank chamber 26 (or inside the housing 23) and the spaces 69 and 70 are provided. Absorbs the pressure difference and pressure fluctuation from the (operating space), and automatically adjusts the pressure to prevent the oil seal bellows 53, 58 from being deteriorated or broken, and to improve the operation performance and durability of the Stirling refrigerator. We are trying to improve.
[0036]
In short, the Stirling refrigerator of the present invention employs a configuration in which the crank chamber 26 and the working spaces 69 and 70 have the same pressure. However, when the Stirling refrigerator is manufactured or maintained, the working gas is supplied or sealed into the crank chamber 26 and the working spaces 69 and 70 from the outside, or when the working gas is discharged to the outside, Depending on the manner, a pressure difference tends to occur between the crank chamber 26 and the working spaces 69 and 70. If there is a pressure difference due to such filling and discharging, even if the buffer tank 59 is provided and the pressure is adjusted as described above, a sufficient effect cannot be obtained.
[0037]
In the Stirling refrigerator according to the present invention, a working gas charging / discharging device 87 is provided to prevent a pressure difference between the crank chamber 26 and the working spaces 69 and 70 when charging and discharging the working gas. It is characterized by the configuration. The housing 23 is provided with a gas stopper 88 that communicates with the crank chamber 26, and the expansion cylinder block 54 is provided with a gas stopper 89 that communicates with the working spaces 69 and 70.
[0038]
FIG. 3 shows a gas circuit diagram of the working gas filling / discharging device 87. The working gas charging / discharging device 87 includes a crank connecting pipe 92 and a working space connecting pipe each having a quick connector 90, 91 at the tip for charging or discharging the working gas in the crank chamber 26 and the working spaces 69, 70, respectively. 93. The working gas charging / discharging device 87 is attached to the Stirling refrigerator 22 by attaching the quick connectors 90 and 91 to the gas stoppers 88 and 89 of the Stirling refrigerator 22.
[0039]
The crank chamber connecting pipe 92 is provided with a pressure sensor 94, and its tip is branched into a crank chamber filling pipe 96 and a crank chamber exhaust pipe 97. The working space connecting pipe 93 is provided with a pressure sensor 95, and its tip is branched into a working space filling pipe 98 and a working space exhaust pipe 99. The crank chamber filling pipe 96 and the working space filling pipe 98 merge into the filling pipe line 100 and are connected to the working gas supply source by the quick connector 102 via the throttle 101. The crank exhaust pipe 97 and the working exhaust pipe 99 merge into the exhaust pipe 103 and are connected to the exhaust port 106 via the throttle 104 and the electromagnetic valve 105.
[0040]
The crank chamber filling pipe 96 and the working space filling pipe 98 are provided with solenoid valves 107 and 108, respectively. In the crank chamber exhaust pipe 97, an electromagnetic valve 109, an oil mist separator 110, and a filter 111 are sequentially provided toward the exhaust port 106. An electromagnetic valve 112 is provided in the working space exhaust pipe 99. Such a working gas charging / discharging device 87 is not shown, but is charged or discharged with a working gas by using an operation panel equipped with an indicator for the pressure sensors 94 and 95, a solenoid valve opening / closing operation rod, and the like. Perform the operation.
[0041]
Such a working gas charging / discharging device 87 may be installed as an accessory to the Stirling refrigerator 22 or may be a portable independent device. In short, the portable working gas charging / discharging device 87 is connected to the crank chamber 26 and the working spaces 69 and 70 of the Stirling refrigerator 22, respectively, with connection pipes 92 and 93 with pressure sensors 94 and 95, respectively. The filling pipes 96, 98 having the solenoid valves 107, 108, 109, 112 and the exhaust pipes 97, 99 are provided. The filling pipe lines 96, 98 join the filling pipe line 100 and are connected to the working gas supply source. The exhaust pipes 97 and 99 are joined to the exhaust pipe 103 and connected to the gas exhaust port 106. The working gas filling / exhaust gas circuit in which the filling pipe 100 and the exhaust pipe 103 are provided with throttles 101 and 104, respectively. 87, an oil mist separator 110 and a filter 111 are attached to the crank chamber exhaust pipe, and can be moved by a caster or the like.
[0042]
FIG. 4 shows a gas circuit diagram of another embodiment of the working gas charging / discharging device 87. The gas circuit of FIG. 4 has substantially the same configuration as the gas circuit of FIG. 3, but in the gas circuit of FIG. 4, the filling pipes 96 and 98 and the exhaust pipes 97 and 99 are respectively independently provided with pressure sensors 94 The Stirling refrigerator 22 is connected to the corresponding crank chamber 26 and working spaces (working chambers) 69 and 70 via 95, 94 and 95, respectively.
[0043]
Next, the operation of the Stirling cooling apparatus of the above embodiment of the present invention will be described. The crankshaft 34 is rotated in the forward direction by the motor 27, and the crank portions 37 and 38 in the crank chamber 26 are rotated out of phase with each other. The cross guide heads 41 and 42 reciprocate the cross guide liners 43 and 44 through connecting rods 39 and 40 that are rotatably connected to the crank portions 37 and 38. The compression piston 48 and the expansion piston 55 connected to the cross guide heads 41 and 42 via the compression piston rod 50 and the expansion piston rod 57 reciprocate with a phase difference.
[0044]
While the expansion piston 55 is moving about 90 degrees ahead and slowly moving near the top dead center, the compression piston 48 rapidly moves near the middle toward the top dead center to compress the working gas. The compressed working gas flows into the heat exchanger 74 for heat dissipation through the communication hole 77 and the manifold 73. The working gas radiated to the cooling water in the heat radiating heat exchanger 74 is cooled by the regenerator 75 and flows into the low temperature chamber (expansion space) 56 through the flow path 86.
[0045]
When the compression piston 48 is slowly moving near the top dead center, the expansion piston 55 is suddenly moved toward the bottom dead center, and the working gas flowing into the low temperature chamber (expansion space) 56 is suddenly expanded to generate cold. To do. As a result, the cold head 85 surrounding the expansion space is cooled to a low temperature.
[0046]
When the expansion piston 55 moves from the bottom dead center to the top dead center, the compression piston 48 moves from the intermediate position toward the bottom dead center, and the working gas passes from the low temperature chamber (expansion space) 56 through the flow path 86 to the regenerator 75. The refrigerating machine 75 stores the cold heat that flows into the working gas. The cold stored in the regenerator 75 is reused to cool again the working gas sent from the high temperature chamber 49 through the heat radiating heat exchanger 74 as described above.
[0047]
Cold head 85 can be cooled by freezer, refrigerator, throw-in cooler, low temperature liquid circulator, low temperature thermostat for various temperature characteristics tests, thermostatic bath, heat shock test device, freeze dryer, cold cooler, etc. Used for
[0048]
The cooling water heat exchanged by the heat radiating heat exchanger 74 flows from the cooling water circulation pipe 78 to the heat radiating device 79, where it is cooled by the cooling fan 80 and circulated again to the heat radiating heat exchanger 74.
[0049]
In the present invention, since the space between the compression piston rod 50 and the opening 51 is completely sealed by the oil seal bellows 53, oil or oil mist rises from the crank chamber 26 along the compression piston rod 50 and is compressed. The entry into the cylinder 45 is completely prevented. Similarly, since the space between the opening 52 and the expansion piston rod 57 is completely sealed by the oil seal bellows 58, oil and oil mist rise from the crank chamber 26 along the expansion piston rod 57 and expand. Entering into the cylinder 46 is completely prevented.
[0050]
By the way, although the temperature in the space in the housing 23 rises during operation of the Stirling refrigerator, the pressure in the space in the housing 23 rises with this temperature rise. Further, pressure fluctuations occur in the spaces 69 and 70 on the back side of the pistons of the compression piston 48 and the expansion piston 55. The rise in pressure in the space in the housing 23 and the pressure fluctuation in the spaces 69 and 70 are absorbed in the buffer tank 59. In particular, when the pressure adjusting bellows 61 is provided, the rising pressure due to the temperature rise in the space in the housing 23 increases the pressure in the chamber 65 via the pipe 71 and causes the pressure adjusting bellows 61 to contract. This is effectively absorbed.
[0051]
The motor 27 of the Stirling refrigerator 22 is reversely rotated. Then, the compression piston 48 and the expansion piston 55 have a phase difference of about 90 degrees, and the compression piston 48 acts as the expansion piston 55 and is opposite to the normal rotation operation of the motor 27, and the expansion piston 55 is the compression piston 48. Acts as Thereby, the working gas in the expansion space of the expansion cylinder is compressed by the expansion piston 55 and generates heat. This reverse rotation is used when performing temperature control operation with a Stirling refrigerator or when defrosting frost generated in a cold heat exchanger of a cold energy utilization device.
[0052]
This reverse rotation also raises the temperature of the expansion cylinder 46, and there is a problem of so-called carbonization in which oil and oil mist rising up oil is heated and carbonized and adheres to the inside of the cylinder, but the oil rising is completely prevented by the oil seal bellows 58. This problem of carbonization does not occur because it is prevented.
Shown in (c).
[0053]
When the working gas is filled in the crank chamber 26 and the working spaces 69 and 70 during the manufacture or maintenance of the Stirling refrigerator of the present invention, the solenoid valves 107 and 108 of the crank chamber filling pipe 96 and the working space filling pipe 98 are provided. Each is opened and filled with working gas from a working gas source. When exhausting the working gas from the crank chamber 26 and the working spaces 69, 70, the crank chamber exhaust pipe 97, the working space exhaust pipe 99, and the electromagnetic valves 109, 112, 105 of the exhaust pipe 103 are opened to operate. The gas is discharged from the exhaust port 106.
[0054]
By the way, the crank chamber 26 and the working spaces 69 and 70 have different internal structures. Therefore, when the working gas is charged or discharged, pressure loss based on flow resistances different from each other occurs, and the difference in the internal pressure differs. Pressure is generated. This pressure loss is noticeable when the working gas is rapidly filled or discharged.
[0055]
In the gas circuit of the working gas filling / discharging device 87 according to the present invention, since the throttle 101 and the throttle 104 are provided in the filling pipe 100 and the exhaust pipe 104, respectively, the working gas is filled or discharged while being throttled. This prevents pressure loss that tends to occur when the working gas is charged or discharged into the crank chamber 26 and the working spaces 69 and 70. As a result, the occurrence of a pressure difference between the crank chamber 26 and the working spaces 69 and 70 can be prevented, so that deterioration and destruction of the oil seal bellows 53 and 58 due to the pressure difference can be prevented.
[0056]
When the working gas is discharged from the crank chamber 26 and the working spaces 69 and 70, the oil mist is removed by the oil mist separator 110, and the oil itself and the contaminants and contaminants in the oil are further removed by the filter 111. Therefore, the working gas can be discharged from the exhaust port 106 in a clean state.
[0057]
Further, since the crank chamber connecting pipe 92 and the working space connecting pipe 93 are respectively provided with pressure sensors 94, 95, the filling or discharging operation is performed manually or based on the pressure detected by the pressure sensors 94, 95. Pressure adjustment can be performed while mechanically operating the solenoid valve.
[0058]
The embodiments of the present invention have been specifically described based on the examples. However, the present invention is not limited to the above-described examples, and various modifications can be made within the scope of the technical matters described in the claims. It goes without saying that there are various examples. In the above embodiment, the two-piston type Stirling refrigerator has been described. However, it goes without saying that the working gas charging / discharging device according to the present invention can be applied to other types of Stirling refrigerators such as a displacer type and other Stirling equipment. Yes.
[0059]
【The invention's effect】
According to the Stirling refrigerator of the present invention having the above configuration, the housing, the compression piston rod, and the expansion piston rod are completely sealed with the oil seal bellows, respectively, so that oil rising contamination (oil rising dirt) ) Can be prevented.
[0060]
Then, the pressure increase due to the temperature increase in the crank chamber is eliminated by providing a buffer tank with or without a pressure adjusting bellows, and between the crank chamber and the working space, which is likely to occur when the working gas is charged and discharged. By preventing the differential pressure with a working gas filling / exhausting device having a throttle, deterioration and destruction of the oil seal bellows can be prevented, and the performance and durability of the Stirling refrigerator can be improved.
[0061]
By solving the above problems specific to Stirling refrigerators, it is possible to use low-melting-point refrigerants such as ethyl alcohol, nitrogen, and helium as working gases other than Freon, and the operating temperature is wider than conventional cooling devices. Thus, it is possible to provide a refrigeration apparatus that can be applied to a wide range of uses of cold energy and that is suitable for global environmental problems and has a large refrigeration capacity and can be heated and cooled by forward and reverse operation of a motor.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a conventional Stirling refrigerator.
FIG. 2 is a diagram showing an embodiment of a Stirling refrigerator according to the present invention.
FIG. 3 is a diagram showing a gas circuit of a working gas charging / discharging device of a Stirling refrigerator according to the present invention.
FIG. 4 is a diagram showing a gas circuit of another embodiment of the working gas charging / discharging device of the Stirling refrigerator according to the present invention.
[Explanation of symbols]
22 Stirling refrigerator
23 Housing
25 Motor room
26 Crank chamber
27 Motor
45 Compression cylinder
46 Expansion cylinder
48 compression piston
49 High greenhouse
50 compression piston rod
53, 58 Bellows for oil seal
55 Expansion piston
56 Low greenhouse
57 Expansion piston rod
59 Buffer tank
61 Buffer tank pressure adjustment bellows
69, 70 Space on the back side of the compression piston and expansion piston (working space)
87 Working gas filling and discharging device
92 Crank chamber connection pipe
93 Working space connection pipe
100 Filling pipeline
101, 104 aperture
103 Exhaust pipe
110 Oil mist separator
111 filter

Claims (5)

A housing having a crank chamber;
A compression cylinder and an expansion cylinder disposed above the crank chamber;
A compression piston and an expansion piston that reciprocate in the compression cylinder and the expansion cylinder to compress and expand the working gas;
In conjunction with the crank in the crank chamber, a compression piston rod and an expansion piston rod having one end connected to the compression piston and the expansion piston;
In a Stirling refrigerator comprising an oil seal disposed at each opening of the top of the crank chamber through which the compression piston rod and the expansion piston rod penetrate,
Each of the oil seals is composed of an oil seal bellows whose base end is fixed to the periphery of the opening and whose tip is fixed to the compression piston rod and the expansion piston rod.
A working gas filling and discharging device for filling or discharging working gas in the working space on the back side of the compression piston and the expansion piston in the compression chamber and the expansion cylinder in the crank chamber and the working space. A Stirling refrigerator characterized by being arranged to communicate with each other. The Stirling refrigerator according to claim 1, wherein a buffer tank is provided between the housing and the working space to absorb pressure fluctuations in the working space and a pressure increase in the housing. The Stirling refrigerator according to claim 1 or 2, wherein the buffer tank has a pressure adjusting bellows disposed therein. The working gas filling / discharging device includes a connecting pipe, a filling pipe, and an exhaust pipe for the crank chamber and the working space, respectively, and the filling pipe of the crank chamber and the filling pipe of the working space are filled. The exhaust pipe of the crank chamber and the exhaust pipe of the working space are joined to the exhaust pipe and connected to the gas exhaust port, and the charging pipe and the exhaust pipe are joined. The Stirling refrigerator according to claim 1, 2 or 3, wherein a throttle is provided in each of the paths. A working gas charging / discharging device for a portable Stirling refrigerator having a working gas filling / exhaust gas circuit for charging and discharging the working gas in the Stirling refrigerator,
The working gas filling / exhaust gas circuit includes a connecting pipe with a pressure sensor connected to a crank chamber of a Stirling refrigerator, a compression piston of the compression cylinder and the expansion cylinder, and a working space on the back side of the expansion piston, and It has a filling pipe and an exhaust pipe having a solenoid valve,
The crank chamber filling pipe and the working space filling pipe merge and are connected to the filling pipe line to communicate with the working gas supply source,
The exhaust pipe of the crank chamber and the exhaust pipe of the working space merge and are connected to the exhaust pipe and communicated with the exhaust port,
The filling line and the exhaust line each have a throttle,
A working gas charging / discharging device for a Stirling refrigerator, wherein the exhaust pipe of the crank chamber is formed by sequentially arranging an oil mist separator and a filter.

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