JP2013002687A - Cold storage refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold storage refrigerator capable of reducing an amount of lubricant flowing out of an inner space of a bearing member, reducing an amount of foreign objects mixed into the inner space of the bearing member, and preventing deformation of a sealing member of the bearing member.SOLUTION: The cold storage refrigerator includes: a cylinder; a cold accumulator; a rotary drive unit generating driving force for reciprocating the cold accumulator; a rotary member 31a being driven and rotated by the rotary drive unit; an inner wheel member 61 and an outer wheel member 62 provided to relatively rotate around the same rotary shaft RA; and the bearing member 60 including two sealing members 63-1, 63-2 respectively provided to both front/back sides of the inner wheel member 61 and the outer wheel member 62 along the rotary shaft RA for rotatably supporting the rotary member 31a. The sealing members 63-1, 63-2 are fixed to one of the inner wheel member 61 and the outer wheel member 62, and a gap G is formed between the wheel member fixed with the sealing members and the other wheel member.

Description

  The present invention relates to a regenerator refrigerator that stores cold heat generated by expanding refrigerant gas in a regenerator.

  As a cryogenic refrigerator for obtaining an extremely low temperature of about 4K, for example, a Gifford-McMahon (GM) refrigerator is used.

  The GM refrigerator generates cold by supplying a refrigerant gas made of, for example, helium gas from a compressor to an expansion space formed in the cylinder, and expanding the supplied refrigerant gas in the expansion space.

  Each stage of the GM refrigerator has a cylinder and a displacer provided in the cylinder. The displacer is provided in the cylinder so as to be able to reciprocate, and forms an expansion space between one end of the displacer and the cylinder. Inside the displacer, a refrigerant gas passage for supplying and discharging refrigerant gas to and from the expansion space is formed. In addition, the refrigerant gas passage formed inside the displacer contains a regenerator material for accumulating cold heat in contact with the refrigerant gas.

  Some of such GM refrigerators include, for example, a motor, a crank member, and a scotch yoke in order to drive the displacer back and forth (see, for example, Patent Document 1). Some of such GM refrigerators have a rotary valve device that communicates by switching a cylinder to a high pressure side or a low pressure side of a compressor.

JP 2007-205581 A

  The GM refrigerator is, for example, a bearing member that rotatably supports a rotating shaft of a motor, a bearing member provided between a crank member and a scotch yoke, or a bearing member that rotatably supports a valve body of a rotary valve device. And the like.

  The bearing member has an inner ring, an outer ring, a rolling element, and a cage. The inner ring and the outer ring are provided so as to be relatively rotatable about the same rotation axis. Between the inner ring and the outer ring, for example, rolling elements having a spherical shape are provided at equal intervals along the circumferential direction around the rotation axis in a state of being held by a cage.

  Some of such bearing members are provided with two seal members for enclosing a lubricant along the rotation axis on both the front and rear sides of the inner ring and the outer ring. A lubricant is sealed in an internal space surrounded by the inner ring, the outer ring, and the two seal members. The two sealing members are fixed to the outer ring.

  However, since the sealing member is in contact with the inner ring to enclose the lubricant, the inner space surrounded by the inner ring, the outer ring, and the two sealing members has airtightness to the outside of the bearing member. . Further, when the cylinder is switched to the high pressure side or the low pressure side of the compressor and communicated with the rotary valve device, the pressure outside the bearing member greatly fluctuates. And with the fluctuation | variation of the pressure outside a bearing member, a big pressure difference generate | occur | produces between the internal space of a bearing member and the exterior, and there exists a possibility that a sealing member may receive a big force with the generated pressure difference, and may deform | transform.

  Moreover, the above-described problems are common not only to GM refrigerators but also to various regenerator refrigerators that include a regenerator and that includes a regenerator that stores cold heat generated by expanding refrigerant gas in the regenerator. It is a problem to do.

  The present invention has been made in view of the above points, and can reduce the amount of lubricant flowing out from the internal space of the bearing member, reduce the amount of foreign matter mixed into the internal space of the bearing member, and reduce the amount of the bearing member. A regenerator type refrigerator that can prevent deformation of a seal member is provided.

  In order to solve the above problems, the present invention is characterized by the following measures.

  The present invention provides a cylinder for expanding a refrigerant gas, a reciprocating motion provided in the cylinder, and a cold storage material housed therein, and the cold generated by the expansion of the refrigerant gas is stored in the cold storage. A regenerator that cools the material, a rotary drive that generates a driving force for reciprocating the regenerator, a rotary member that is driven to rotate by the rotary drive, and a rotary member that can rotate relative to each other about the same rotational axis A lubricant is sealed between the inner ring member and the outer ring member that are provided on the front and rear sides of the inner ring member and the outer ring member, respectively, along the rotation axis. And a bearing member that rotatably supports the rotating member, and the two sealing members are fixed to one of the inner ring member and the outer ring member. When Moni, and is provided so that a gap is formed between the other member, a regenerator refrigerator.

  Moreover, in the above-described regenerator type refrigerator, the present invention is such that the two seal members are made of resin at least at a portion facing the other member across the gap.

  Moreover, in the above-described regenerator type refrigerator, the present invention has a width dimension of 10 to 100 μm.

  Moreover, the present invention is the above-described regenerator-type refrigerator, wherein the rotating member is a rotating shaft of the rotation driving unit.

  Further, the present invention is the above-described regenerator type refrigerator, wherein the rotating member is a crank member, and the displacer is reciprocally driven by converting the rotational driving force of the crank member to be rotationally driven into a reciprocating driving force. A scotch yoke is provided, and the bearing member is provided on the scotch yoke.

  The present invention further includes a compressor that compresses the refrigerant gas sucked from the cylinder and discharges the compressed refrigerant gas to the cylinder in the regenerator type refrigerator described above, and the rotating member includes the cylinder. The rotary valve is switched to the suction side or the discharge side of the compressor to communicate with each other.

  According to the present invention, the amount of lubricant flowing out from the internal space of the bearing member can be reduced, the amount of foreign matter mixed into the internal space of the bearing member can be reduced, and deformation of the seal member of the bearing member can be prevented.

It is sectional drawing which shows the structure of the GM refrigerator which concerns on embodiment. It is a perspective view which expands and shows a bearing member. It is a disassembled perspective view of a Scotch yoke mechanism. It is a disassembled perspective view of a rotary valve device. It is sectional drawing which shows the structure of a bearing member. It is sectional drawing which shows the structure of the bearing member of the GM refrigerator which concerns on the comparative example 1. FIG. It is sectional drawing which shows the structure of the bearing member of the GM refrigerator which concerns on the comparative example 2.

Next, a mode for carrying out the present invention will be described with reference to the drawings.
(Embodiment)
With reference to FIG. 1, the GM refrigerator is illustrated and demonstrated about the regenerator type refrigerator which concerns on embodiment. The GM refrigerator has a two-stage configuration suitable for obtaining a cryogenic temperature of about several K to 20K.

  FIG. 1 is a cross-sectional view showing the configuration of the GM refrigerator according to the present embodiment. FIG. 2 is an enlarged perspective view showing the bearing member 60. FIG. 3 is an exploded perspective view of the scotch yoke mechanism 32. FIG. 4 is an exploded perspective view of the rotary valve device 40.

  The GM refrigerator has a compressor 1, a cylinder part 2 and a housing part 3.

  The compressor 1 sucks refrigerant gas (helium gas) from the low pressure side 1a. Then, the sucked refrigerant gas is compressed to increase the pressure and cool, and discharged to the high pressure side 1b. The pressure on the high-pressure side 1b can be about 2 MPa, for example, and the pressure on the low-pressure side 1a can be about 0.5 MPa, for example.

  The cylinder unit 2 includes a first stage cylinder 11, a second stage cylinder 12, a first stage displacer 13, a second stage displacer 14, internal spaces 15 and 16, and cold storage materials 17 and 18.

  The first stage cylinder 11 and the second stage cylinder 12 are arranged in two upper and lower stages. A first-stage displacer 13 and a second-stage displacer 14 are provided in the first-stage cylinder 11 and the second-stage cylinder 12 so as to reciprocate while sliding.

  Expansion spaces 21, 22, and 23 are formed between the first stage displacer 13, the second stage displacer 14, and the first stage cylinder 11 and the second stage cylinder 12. An internal space 15 is formed inside the first stage displacer 13. An internal space 16 is formed inside the second stage displacer 14. Cold storage materials 17 and 18 are accommodated in the internal spaces 15 and 16, respectively.

  The expansion spaces 21, 22, and 23 are connected to each other by the internal spaces 15 and 16 and refrigerant gas flow paths L <b> 1 to L <b> 4 provided in the first stage displacer 13 and the second stage displacer 14. . Therefore, the internal spaces 15 and 16 are also refrigerant gas flow paths for supplying and discharging refrigerant gas to the expansion spaces 21, 22, and 23.

  Further, flanges 19 and 20 are provided on the outer periphery of the lower portion of the first stage cylinder 11 and the second stage cylinder 12 so as to be thermally coupled, respectively.

  As will be described later, the first-stage displacer 13 and the second-stage displacer 14 store the cold heat generated by the expansion of the refrigerant gas in the expansion spaces 21 and 22 in the regenerator materials 17 and 18, respectively. Yes, corresponding to the regenerator in the present invention.

  As shown in FIG. 1, the housing part 3 includes a drive device 30 and a rotary valve device 40.

  The drive device 30 includes a motor 31 and a scotch yoke mechanism 32. The motor 31 generates a rotational driving force. The motor 31 corresponds to the rotation drive unit in the present invention.

  As shown in FIG. 1, the rotating shaft 31a of the motor 31 is rotatably supported by bearing members 60 provided on both front and rear sides of the motor 31 along the rotating shaft 31a. As shown in FIG. 2, the bearing member 60 includes an inner ring 61, an outer ring 62, and a seal member 63 that are provided to be rotatable relative to each other. The seal member 63 is fixed to the outer ring 62 and is provided so that a gap G is formed between the seal member 63 and the inner ring 61. The inner ring 61 is fixed to the rotating shaft 31a. The detailed structure of the other bearing member 60 will be described later with reference to FIG.

  As shown in FIG. 3, the scotch yoke mechanism 32 has a crank member 33 and a scotch yoke 34, converts the rotational driving force generated by the motor 31 into a reciprocating driving force, and the first stage displacer 13 and the second stage displacer 13. This is for reciprocating the eye displacer 14.

  The crank member 33 is fixed to the rotation shaft 31 a of the motor 31 and is driven to rotate by the motor 31. The crank member 33 is configured such that a crank pin 33b is provided at a position eccentric from a position where the crank member 33 is attached to the rotation shaft 31a of the motor 31. Therefore, when the crank member 33 is attached to the rotating shaft 31a of the motor 31, the rotating shaft 31a and the crank pin 33b are in an eccentric state.

  The scotch yoke 34 includes a yoke plate 35, a vertical shaft 36, and a bearing member 60A. The scotch yoke 34 is provided in the housing portion 3 so as to be capable of reciprocating in the Z1 and Z2 directions in FIGS. A vertical shaft 36 is provided at the central vertical position of the yoke plate 35 so as to extend in the vertical direction (Z1 and Z2 directions). The vertical shaft 36 is supported by sliding bearings 38a and 38b so as to be slidable in the vertical direction (Z1 and Z2 directions).

  The yoke plate 35 is formed with a horizontally long window 35a extending in the directions of arrows X1 and X2 in FIG. 3, and a bearing member 60A is provided in the horizontally long window 35a. The bearing member 60A is provided so as to be able to roll in the directions of arrows X1 and X2 within the horizontally elongated window 35a.

  The bearing member 60A includes an inner ring 61, an outer ring 62, and a seal member 63 that are provided so as to be rotatable relative to each other, and is configured in the same manner as the bearing member 60 described above. The seal member 63 is fixed to the outer ring 62 and is provided so that a gap G is formed between the seal member 63 and the inner ring 61. The inner ring 61 is fixed to the crankpin 33b. The detailed structure of the other bearing member 60A is the same as that of the bearing member 60 described later with reference to FIG.

  When the rotation shaft 31a rotates with the crank pin 33b fixed to the bearing member 60A, the crank pin 33b rotates (eccentric rotation) so as to draw an arc, and the scotch yoke 34 moves in the directions of arrows Z1 and Z2 in FIG. Reciprocate. At this time, the bearing member 60A reciprocates in the horizontal window 35a in the directions of arrows X1 and X2 in FIG.

  A vertical shaft 36 provided at the lower part of the scotch yoke 34 is connected to the first stage displacer 13. Therefore, the Scotch yoke 34 reciprocates the first stage displacer 13 in the directions of arrows Z1 and Z2 in FIG.

  The crank member 33 is restricted from moving in the axial direction (Y1, Y2 direction) of the crankpin 33b, and the scotch yoke 34 is also restricted from moving in the axial direction (Y1, Y2 direction) of the crankpin 33b. Yes.

  The crank pin 33b corresponds to a crank member in the present invention.

  As shown in FIG. 1, the rotary valve device 40 is provided between the compressor 1 and the first stage cylinder 11 and the second stage cylinder 12. The rotary valve device 40 is for controlling the flow of the refrigerant gas. Specifically, the rotary valve device 40 switches the first-stage cylinder 11 and the second-stage cylinder 12 to communicate with each other by switching to the high-pressure side 1 b of the compressor 1. At this time, the refrigerant gas discharged from the high pressure side 1 b of the compressor 1 is sucked into the first stage cylinder 11 and the second stage cylinder 12. Further, the rotary valve device 40 switches the first stage cylinder 11 and the second stage cylinder 12 to communicate with each other by switching to the low pressure side 1 a of the compressor 1. At this time, the refrigerant gas exhausted from the first stage cylinder 11 and the second stage cylinder 12 includes a space 4 provided inside the housing part 3, a space 4 provided above the housing part 3, and the space 4. It passes through the communicating low pressure side pipe 5 and is sucked into the low pressure side 1 a of the compressor 1. By repeating such an operation, the rotary valve device 40 switches the first-stage cylinder 11 and the second-stage cylinder 12 to the low-pressure side 1a or the high-pressure side 1b of the compressor 1 to communicate with each other. The low pressure side 1a of the compressor 1 corresponds to the suction side in the present invention, and the high pressure side 1b of the compressor 1 corresponds to the discharge side in the present invention.

  As shown in FIGS. 1 and 4, the rotary valve device 40 includes a valve body 41 and a valve plate 42. The valve body 41 and the valve plate 42 have flat surfaces, and the flat surfaces are in surface contact with each other.

  The valve body 41 is fixed in the housing part 3 by a fixing pin 43. On the other hand, as shown in FIG. 3, the valve plate 42 rotates so that the crank pin 33 b rotates (eccentric rotation) about the crank shaft 33 a (the rotation shaft 31 a of the motor 31), so that the valve plate 42 rotates. The front end of the crank pin 33b is engaged.

  As shown in FIGS. 1 and 4, the valve plate 42 is rotatably supported by a bearing member 60B. The bearing member 60B includes an inner ring 61, an outer ring 62, and a seal member 63 that are provided to be rotatable relative to each other, and is configured in the same manner as the bearing member 60 described above. The seal member 63 is fixed to the outer ring 62 and is provided so that a gap G is formed between the seal member 63 and the inner ring 61. The inner ring 61 is fixed to the valve plate 42. The detailed structure of the other bearing member 60B is the same as that of the bearing member 60 described later with reference to FIG.

  In FIG. 4, for ease of illustration, the bearing member 60 </ b> B is indicated by a dotted line. The valve plate 42 corresponds to the rotary valve in the present invention.

  In the center of the valve body 41, a refrigerant gas intake hole 44 connected to the high-pressure side 1b of the compressor 1 is penetrated. As shown in FIG. 4, the valve plate side end face 45 is provided with an arc-shaped groove 46 on a concentric circle centered on the refrigerant gas intake hole 44. The valve body 41 is provided with a through hole 48 having one end opened in the arc-shaped groove 46 and the other end opened as a discharge hole 47 in the side surface of the valve body 41. Further, the discharge hole 47 communicates with the expansion space 23 via a passage 49 (see FIG. 1).

  On the valve body side end surface 50 of the valve plate 42, a groove 51 extending in the radial direction from the center thereof is provided. Further, an arc-shaped hole 53 is formed at a position on the same circumference as the arc-shaped groove 46 of the valve body 41 so as to penetrate from the valve body-side end face 50 to the opposite end face 52 of the valve plate 42.

  The refrigerant gas intake hole 44, the groove 51, the arc-shaped groove 46, and the through hole 48 constitute an intake valve. Further, the exhaust hole is configured by the through hole 48, the arc-shaped groove 46, and the arc-shaped hole 53.

  When the scotch yoke 34 reciprocates in the Z1 and Z2 directions, the first-stage displacer 13 and the second-stage displacer 14 are reciprocated in the Z1 and Z2 directions, respectively, in the first-stage cylinder 11 and the second-stage cylinder, respectively. The cylinder 12 reciprocates between the bottom dead center LP and the top dead center UP.

  When the first stage displacer 13 and the second stage displacer 14 reach the bottom dead center LP, the exhaust valve is closed and a refrigerant gas flow path is formed between the through hole 48, the arc-shaped groove 46, and the groove 51. Is done. The high-pressure refrigerant gas begins to flow into the expansion space 23 through the passage 49 in the housing part 3. Thereafter, the first-stage displacer 13 and the second-stage displacer 14 start to rise past the bottom dead center LP, and the refrigerant gas passes from the top to the bottom of the regenerator materials 17 and 18 and fills the expansion spaces 21 and 22. It will be done.

  When the first stage displacer 13 and the second stage displacer 14 reach the top dead center UP, the intake valve is closed and the refrigerant gas is interposed between the through hole 48 and the arc-shaped groove 46 and the arc-shaped hole 53. A flow path is formed. In the expansion spaces 21 and 22, the high-pressure refrigerant gas generates cold heat by adiabatic expansion, cools the flanges 19 and 20 by the generated cold heat, and passes from the bottom to the top while cooling the regenerator materials 17 and 18. Then, it begins to flow through the space 4 and the low-pressure side pipe 5 to the low-pressure side 1 a of the compressor 1. At this time, the generated cold energy is stored in the cool storage materials 17 and 18.

  Thereafter, when the first stage displacer 13 and the second stage displacer 14 reach the bottom dead center LP, the exhaust valve is closed and the intake valve is opened to complete one cycle. In this way, by repeating the cycle of compression and expansion of the refrigerant gas, the refrigerator generates cold and can store the generated cold.

  Instead of the rotary valve device 40, a switching device constituted by an intake valve and an exhaust valve is provided on the compressor 1 side outside the housing portion 3, and the compressor 1 and the expansion spaces 21 to 23 are provided by the switching device. May be connected so that the intake valve and the exhaust valve can be switched in synchronization with the reciprocation of the displacer. When the first stage displacer 13 and the second stage displacer 14 reciprocate, the connection between the expansion spaces 21 to 23 and the low pressure side 1a and high pressure side 1b of the compressor 1 is switched by the switching device. The cycle of refrigerant gas compression and expansion can be repeated. At this time, the bearing member 60B is not provided.

  Next, the structure of the bearing members 60, 60A, and 60B will be described. Below, bearing member 60, 60A, 60B is represented and the bearing member 60 is demonstrated, However, Bearing member 60A, 60B can also be set as the structure similar to the bearing member 60. FIG.

  FIG. 5 is a cross-sectional view showing the configuration of the bearing member 60. In FIG. 5, the rotation shaft 31 a fixed to the inner ring 61 is also illustrated. In the bearing member 60A, a crank pin 33b is fixed to the inner ring 61 instead of the rotating shaft 31a. In the bearing member 60B, the valve plate 42 is fixed to the inner ring 61 in place of the rotating shaft 31a.

  As shown in FIG. 5, the bearing member 60 includes an inner ring 61, an outer ring 62, a seal member 63, a rolling element 64, and a cage 65.

  The inner ring 61 corresponds to the inner ring member in the present invention, and the outer ring 62 corresponds to the outer ring member in the present invention.

  The inner ring 61 and the outer ring 62 are provided so as to be relatively rotatable about the same rotation axis RA. An inner ring 61 is incorporated in the outer ring 62.

  Between the inner peripheral surface of the outer ring 62 and the outer peripheral surface of the inner ring 61, a rolling element 64 is provided for making the outer ring 62 rotatable relative to the inner ring 61. As the rolling element 64, for example, a spherical shape (ball bearing), a cylindrical shape (needle bearing), or the like can be used. Further, a cage for holding the rolling elements 64 between the outer ring 62 and the inner ring 61 in a state where the interval between the rolling elements 64 adjacent to each other along the circumferential direction around the rotation axis RA is constant. 65 is provided.

  As described above with reference to FIGS. 1 and 2, the inner ring 61 is fixed to the rotating shaft 31a. On the other hand, the outer ring 62 is fixed to the housing part 3 of the GM refrigerator. Therefore, the bearing member 60 including the inner ring 61 and the outer ring 62 rotatably supports the rotary shaft 31a in the GM refrigerator.

  As materials for the inner ring 61, the outer ring 62, the rolling elements 64, and the cage 65, for example, martensitic stainless steel such as SUS440C or ferritic stainless steel that has been subjected to appropriate thermosetting treatment, precipitation hardening stainless steel such as SUS630. Steel, or austenitic stainless steel such as SUS316 that has been subjected to surface hardening treatment can be used.

  In an internal space S formed between the inner ring 61 and the outer ring 62, a lubricant made of grease, for example, is enclosed. Then, seal members 63-1 and 63-2 are provided on both front and rear sides (right and left sides in FIG. 5) of the inner ring 61 and the outer ring 62 along the rotation axis RA. The seal members 63-1 and 63-2 are for sealing a lubricant between the inner ring 61 and the outer ring 62.

  The seal members 63-1 and 63-2 are fixed to the outer ring 62. The seal members 63-1 and 63-2 are fixed to the outer ring 62 by, for example, adhesion along the circumferential direction centering on the rotation axis RA, and no gap is formed between the sealing members 63-1 and 63-2. On the other hand, the seal members 63-1 and 63-2 are not fixed to the inner ring 61. The seal members 63-1 and 63-2 are provided so that a gap G is formed between the seal members 63-1 and 63-2 and the inner ring 61 along the circumferential direction around the rotation axis RA. Thereby, the amount of lubricant flowing out from the internal space S can be reduced, the amount of foreign matter mixed into the internal space S can be reduced, and deformation of the seal members 63-1 and 63-2 can be prevented.

  Here, the amount of lubricant flowing out from the internal space S can be reduced, the amount of foreign matter mixed into the internal space S can be reduced, and the effect of preventing deformation of the seal members 63-1 and 63-2 can be compared. This will be described with reference to Examples 1 and 2.

  FIG. 6 is a cross-sectional view illustrating a configuration of a bearing member 60a of the GM refrigerator according to Comparative Example 1. FIG. 7 is a cross-sectional view showing a configuration of a bearing member 60b of the GM refrigerator according to Comparative Example 2.

  In Comparative Example 1, the bearing member 60a is not provided with a seal member, and is provided with shield plates 63a-1 and 63a-2 made of steel plates instead of the seal member. The shield plates 63a-1 and 63a-2 are provided far away from the inner ring 61 and do not have a function of sealing the lubricant. Therefore, the amount of lubricant flowing out from the internal space S through the LG between the shield plates 63a-1 and 63a-2 and the inner ring 61 increases. In addition, the amount of foreign matter such as wear powder generated from each sliding portion of the GM refrigerator enters the internal space S through LG between the shield plates 63a-1 and 63a-2 and the inner ring 61 increases.

  In Comparative Example 2, the bearing member 60b is provided with the seal members 63b-1 and 63b-2, but a gap is formed between the seal members 63b-1 and 63b-2 and the inner ring 61. There is no contact. For this reason, the internal space S surrounded by the inner ring 61, the outer ring 62, and the two sealing members 63b-1 and 63b-2 has airtightness to the outside of the bearing member 60b. As described above, when the cylinders 11 and 12 are switched to the high pressure side 1b or the low pressure side 1a of the compressor 1 to communicate with each other, the pressure in the space 4 provided in the housing portion 3 is For example, it fluctuates between 2 MPa and, for example, 0.5 MPa on the low pressure side 1a. A large pressure difference is generated between the internal space S of the bearing member 60b and the outside as the pressure in the space 4 varies, and the seal members 63b-1 and 63b-2 receive a large force due to the generated pressure difference. There is a risk of deformation. Further, the inner ring 61 and the seal members 63b-1 and 63b-2 may come into contact with each other and slide, and there is a possibility that the torque required to rotate the inner ring 61 and the outer ring 62 relatively increases.

  On the other hand, in the present embodiment, the seal members 63-1 and 63-2 are provided so as to be fixed to the outer ring 62 and to form a gap G with the inner ring 61. Thereby, the quantity which a lubricant flows out from internal space S through between seal members 63-1, 63-2 and inner ring 61 can be reduced. Further, it is possible to reduce the amount of foreign matter such as abrasion powder generated from each sliding portion of the GM refrigerator entering the internal space S through the space between the seal members 63-1 and 63-2 and the inner ring 61. it can. Further, when the cylinders 11 and 12 are switched to communicate with the high pressure side 1b or the low pressure side 1a of the compressor 1, the seal members 63-1 and 63-2 are deformed due to fluctuations in pressure in the space 4 of the housing portion 3. Can be prevented. Further, it is possible to prevent an increase in the torque required to cause the inner ring 61 and the outer ring 62 to rotate relative to each other by sliding the inner ring 61 and the seal members 63-1, 63-2 in contact with each other.

  The width dimension GW of the gap G along the radial direction around the rotation axis RA is preferably 10 to 100 μm. This is because when the width dimension GW exceeds 100 μm, the amount of lubricant flowing out from the internal space S may increase, or the amount of foreign matter mixed into the internal space S may increase. In addition, when the width dimension GW is less than 10 μm, the airtightness of the internal space S is increased, and when the cylinders 11 and 12 are switched to the high pressure side 1b or the low pressure side 1a of the compressor 1 to communicate with each other, the space 4 of the housing portion 3 is used. This is because the seal members 63-1 and 63-2 may be deformed due to fluctuations in pressure. Alternatively, when the width dimension GW is less than 10 μm, the inner ring 61 and the seal members 63-1 and 63-2 slide in contact with each other due to dimensional tolerances, and the inner ring 61 and the outer ring 62 rotate relative to each other. This is because there is a possibility that the torque required to increase the torque will increase.

  Further, it is preferable that at least a portion of the seal members 63-1 and 63-2 facing the inner ring 61 with the gap G interposed therebetween is made of resin. As the resin, synthetic rubber such as NBR or ACN (acrylic rubber), PTFE It is more preferable to use a fluorine resin or the like. As a result, even when the inner ring 61 and the seal members 63-1, 63-2 slide in contact with each other due to dimensional tolerances or the like, the increase in torque can be reduced, so the width dimension GW Can be set small, and the outflow amount of the lubricant and the mixing amount of foreign matters can be further reduced. Further, even when the inner ring 61 and the seal members 63-1, 63-2 are in contact with each other and slide, the inner ring 61 and the like can be prevented from being damaged. As a result, the life of the bearing member 60 can be extended.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims. Can be modified or changed.

  For example, in the present embodiment, the example in which the seal members 63-1 and 63-2 are fixed to the outer ring 62 and provided so that the gap G is formed between the inner ring 61 and the seal member 63-1, 63-2 has been described. However, the seal members 63-1 and 63-2 may be provided so that the gap G is formed between the seal members 63-1 and 63-2 and the outer ring 62 while being fixed to the inner ring 61. That is, the seal members 63-1 and 63-2 are fixed to one of the inner ring 61 and the outer ring 62 and may be provided so that a gap G is formed between the other members. Good.

  Further, in any one or two of the three bearing members 60, 60A, 60B, the seal members 63-1 and 63-2 are fixed to one member of the inner ring 61 and the outer ring 62, and the other It may be provided so that a gap G is formed between these members.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Cylinder part 3 Housing part 11 1st stage cylinder 12 2nd stage cylinder 13 1st stage displacer 14 2nd stage displacer 15, 16 Internal space 17, 18 Cold storage material 21, 22, 23 Expansion space 30 Driving device 31 Motor 31a Rotating shaft 32 Scotch yoke mechanism 33 Crank member 33a Crank shaft 33b Crank pin 34 Scotch yoke 40 Rotary valve device 41 Valve main body 42 Valve plate 60, 60A, 60B Bearing member 61 Inner ring 62 Outer ring 63, 63-1 63-2 Seal member 64 Rolling element 65 Cage

Claims (6)

A cylinder for expanding the refrigerant gas;
A regenerator that is provided in the cylinder so as to be capable of reciprocating, and in which a regenerator material is housed; and a regenerator that stores cold heat generated in association with expansion of the refrigerant gas in the regenerator material;
A rotation drive unit that generates a driving force for reciprocating the regenerator;
A rotating member that is rotationally driven by the rotational driving unit;
An inner ring member and an outer ring member provided so as to be rotatable relative to each other about the same rotation axis, and the inner ring member and the outer ring provided respectively on the front and rear sides of the inner ring member and the outer ring member along the rotation axis. Two seal members for enclosing a lubricant between the members, and a bearing member that rotatably supports the rotating member,
The two seal members are fixed to one of the inner ring member and the outer ring member, and are provided so that a gap is formed between the other members, a regenerator type refrigerator.   The regenerator-type refrigerator according to claim 1, wherein at least a portion of the two seal members facing the other member across the gap is made of resin.   The regenerator type refrigerator according to claim 1 or 2, wherein a width dimension of the gap is 10 to 100 µm.   The regenerator refrigerator according to any one of claims 1 to 3, wherein the rotating member is a rotating shaft of the rotation driving unit. The rotating member is a crank member;
A scotch yoke that reciprocally drives the displacer by converting a rotational driving force of the crank member to be rotationally driven into a reciprocating driving force;
The regenerative refrigerator according to any one of claims 1 to 3, wherein the bearing member is provided in the scotch yoke. A compressor that compresses the refrigerant gas sucked from the cylinder and discharges the compressed refrigerant gas to the cylinder;
The regenerator type refrigerator according to any one of claims 1 to 3, wherein the rotating member is a rotary valve that switches the cylinder to communicate with the suction side or the discharge side of the compressor.

Images