JP2012087711A - Hermetic compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly-efficient, highly-reliable hermetic compressor that reduces sliding loss in a thrust part and prevents increase in a surface pressure.SOLUTION: A thrust surface 121 of a main shaft bearing 117 supporting a main shaft part 111 is formed so that an area of the thrust surface 121 is gradually larger in a direction where the thrust surface 121 gets more away from a compressor chamber 116 at the center of an shaft hole 117a. Accordingly, a partial surface pressure in a region remote from the compressor chamber 116 in which a vertical load, which a repulsion load applied by a compression action of a piston 118 acts can be reduced, the sliding loss in the thrust sliding part and uneven attrition can be reduced, and the entire area of the thrust surface 121 can be reduced.

Description

  The present invention relates to a hermetic compressor used in a refrigeration cycle such as a refrigerator-freezer.

  Generally, this type of hermetic compressor has a configuration in which a block that is a support frame, a compression element is arranged above the block, and an electric element is arranged below the block in a hermetic container. .

  And the shaft which fixed the rotor of the electric element is supported rotatably by the bearing part provided in the approximate center of the block, and the driving force of the electric element is transmitted to the compression element by the rotation of the shaft.

  The conventional hermetic compressor will be described below with reference to the drawings.

  FIG. 8 is a sectional view of a conventional hermetic compressor, and FIG. 9 is a front view of a block in the conventional hermetic compressor.

  8 and 9, 1 is a sealed container, 2 is a shaft, 3 is a rotor, 4 is a stator, and the rotor 3 and the stator 4 constitute a motor that is an electric element as a pair. The shaft 2 is press-fitted into the rotor 3. Further, 5 is a connecting rod, 6 is a cylinder, 7 is a piston, 8 is a piston pin, and 9 is a block.

  A compression element mainly composed of the piston 7 and the cylinder 6 by a connecting rod 5 attached to a crankpin 11 which is an eccentric part of the shaft 2 and a piston pin 8 attached to the other end of the connecting rod 5 and fixed to the piston 7. Is formed. Reference numeral 10 denotes refrigerating machine oil which stays in the lower part of the sealed container 1.

  As described above, a crankpin 11 and a counterbalance plate 12 that rotate eccentrically and reciprocately drive the piston 7 of the compression element are provided on the upper portion of the shaft 2. A thrust surface 14 that receives a thrust load is provided on the upper end surface of the bearing portion 15 of the block 9. A thrust sliding portion is formed in the hermetic compressor by directly sliding the thrust surface 14 provided on the upper end surface of the bearing portion 15 of the block 9 and the lower surface of the counterbalance plate 12.

JP 2000-120540 A

  In a compressor in which a compression element is provided above the block 9 that is a support frame and an electric element is provided below the block 9, the pressure in the cylinder 6 and the bore diameter are placed on the side surface of the crankpin 11 of the shaft 2 during the compression process. The reaction force of the piston load governed by is acting as a load.

Further, since the bearing portion 15 provided on the shaft 2 and the block 9 has a clearance of about 10 to 30 μm, the shaft 2 is inclined and contacts at the thrust sliding portion and the journal sliding portion. The thrust sliding part is affected by this piston load, and the shaft 2
And the load more than the dead weight of the rotor 3 acts as a load.

  From the above, the compressor provided with the compression element at the upper part of the block 9 which is the support frame and the electric element at the lower part of the block 9 is affected by the piston load as a thrust load in addition to the own weight of the shaft 2 and the rotor 3. It was added, and the surface pressure of the thrust sliding portion increased locally, so that the so-called one-side contact was likely to occur.

  Therefore, in this conventional hermetic type compressor, in order to reduce the surface pressure of the thrust sliding portion that increases locally, the sliding area of the entire thrust portion is secured and the thrust portion is locally localized. The increase in surface pressure is prevented.

  However, if the sliding area of the thrust sliding portion is increased, the sliding resistance at the thrust sliding portion increases, so the sliding loss of the thrust sliding portion increases and the efficiency decreases. Had.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a highly efficient and highly reliable hermetic compressor.

  In order to solve the above-described conventional problems, a hermetic compressor according to the present invention includes a shaft flange that abuts a front end portion of a main bearing that supports the main shaft portion of the shaft, and the rotor and the shaft. A thrust receiving portion that supports a vertical load due to its own weight and a vertical load of a repulsive load caused by the compression action of the piston is provided, and a surface of the thrust receiving portion on which the flange portion of the shaft comes into contact is a side close to the compression chamber The area on the side farther from the compression chamber is larger than the compression chamber, and the vertical load due to the influence of the piston load is locally applied to the surface of the thrust receiving portion where the flange portion of the shaft abuts. The surface pressure on the load side can be reduced, and the sliding loss and uneven wear of the thrust sliding portion can be reduced.

  The hermetic compressor of the present invention reduces the sliding loss and uneven wear of the thrust sliding part by ensuring the sliding area where the vertical load due to the piston load is locally applied, and with high efficiency. A highly reliable hermetic compressor can be provided.

1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. Front view from above of cylinder block in the first embodiment Sectional drawing of the principal part of the hermetic compressor in the first embodiment The principal part expanded sectional view of the electric element of the hermetic compressor in Embodiment 1 Variation diagram of repulsive load accompanying compression action of hermetic compressor in the first embodiment Longitudinal sectional view of a compression element portion of a hermetic compressor according to a second embodiment of the present invention The disassembled perspective view of the principal part in the compression element part of the hermetic type compressor in Embodiment 2 Vertical section of a conventional hermetic compressor Front view of block of conventional hermetic compressor

The invention according to claim 1 stores lubricating oil in a hermetically sealed container, houses an electric element including a stator and a rotor, and a compression element driven by the electric element. A shaft having an eccentric shaft portion formed through a main shaft portion and a flange portion and having the rotor fixed thereto, a cylinder block having a cylindrical compression chamber, and a piston reciprocating in the compression chamber; A connecting mechanism that connects the piston and the eccentric shaft portion, and a main bearing that is continuous with the cylinder block and supports the main shaft portion of the shaft, and the flange portion of the shaft in the main bearing. A thrust receiving portion for supporting a vertical load due to the weight of the rotor and the shaft and a vertical load of a repulsive load accompanying the compression action of the piston is provided at a tip portion where the rotor and the shaft abut. The surface flange portion abuts the shaft in the thrust receiving portion, than the side closer to the compression chamber is obtained by forming such that the area on the side remote from the compression chamber increases.

  By setting it as this structure, the surface pressure increase at the side which receives the load of the perpendicular direction in the repulsive load accompanying the compression action of a piston can be suppressed.

  In other words, by increasing the area of the thrust surface that receives the locally acting bias load, the area of the thrust surface located on the opposite side of the thrust surface is reduced, and as a result, the entire area of the thrust surface is reduced. The area of the thrust surface that receives the eccentric load and the thrust surface that is located on the opposite side of the thrust surface can be made smaller than the configuration in which the areas are formed substantially uniformly.

  Therefore, the sliding loss of the thrust sliding portion formed by the surface where the flange portion of the shaft contacts the lower surface of the flange portion and the thrust receiving portion is reduced, and the load accompanying the compression action of the piston is locally reduced. By ensuring a large area of the receiving surface and preventing local wear, uneven wear of the thrust receiving part can be suppressed, and as a result, a highly efficient and reliable hermetic compressor is provided. Can do.

  According to a second aspect of the present invention, in the first aspect of the present invention, the shaft hole through which the main shaft portion penetrates and the outer peripheral portion of the bearing communicate with the surface of the thrust receiving portion on which the flange portion of the shaft abuts. An oil groove is provided.

  By adopting such a configuration, the area of the surface that locally receives the load accompanying the compression action of the piston can be secured, and an increase in local surface pressure is suppressed, and more lubricating oil is added to the surface. It can be supplied to a thrust sliding portion formed by a surface where the flange portion of the shaft contacts the lower surface of the flange portion and the shaft receiving portion, and wear of the thrust sliding portion can be reduced.

  According to a third aspect of the invention, in the first or second aspect of the invention, the surface of the thrust receiving portion with which the flange portion of the shaft abuts is inclined so as to gradually become lower as the distance from the compression chamber side increases. It has been made.

  By adopting such a configuration, it is possible to avoid contact of the thrust sliding portion, and it is possible to prevent a local increase in surface pressure. As a result, higher reliability can be obtained in the hermetic compressor.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, nitriding treatment, CrN, TiN, or the like is applied to a surface of the thrust receiving portion on which the flange portion of the shaft abuts. The ceramic coating was applied.

  By setting it as this structure, the low friction coefficient and hardness of the said thrust sliding part can be improved. As a result, the sliding loss of the thrust sliding portion can be further reduced, the efficiency of the hermetic compressor can be increased, and high reliability can be ensured.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the thrust receiving portion is constituted by a part different from the main bearing.

  By adopting such a configuration, the cylinder block having a different thrust receiving portion or the main bearing can be incorporated, and versatility can be improved.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the position of the magnetic center of the rotor is lower than the magnetic center of the stator. It is comprised so that it may become.

  With this configuration, during operation of the electric element, a force that pulls the shaft fixed to the rotor upward by magnetic attraction acts, so that a vertical load (thrust) due to the weight of the rotor and the shaft is exerted. (Load) is reduced, a hermetic compressor having higher reliability can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a hermetic compressor according to Embodiment 1 of the present invention. FIG. 2 is a front view from above of a cylinder block constituting the hermetic compressor in the first embodiment. FIG. 3 is a cross-sectional view of a main part of the hermetic compressor according to the first embodiment. FIG. 4 is an enlarged cross-sectional view of a main part of the electric element constituting the hermetic compressor in the first embodiment. FIG. 5 is a change diagram of the repulsive load accompanying the compression action of the hermetic compressor in the first embodiment.

  In FIG. 1 to FIG. 5, the lubricating oil 102 is stored in the sealed container 101 constituting the hermetic compressor, and the electric element 105 including the stator 103 and the rotor 104, and the electric element 105 A compression element 106 disposed above and driven by the electric element 105 is disposed.

  The shaft 110 that constitutes the compression element 106 includes a main shaft portion 111 on which the rotor 104 is shrink-fitted and fixed, a flange portion 112 formed on the main shaft portion 111, and the flange portion 112 that is eccentric with respect to the main shaft portion 111. An eccentric shaft portion 113 formed at a position is provided. In addition, an oil supply mechanism 114 is provided inside the shaft 110, and an oil supply groove 114 a having one end communicating with the oil supply mechanism 114 and the other end extending to the lower surface of the flange portion 112 is provided on the surface of the shaft 110 in a spiral shape. It has been.

  A cylinder block 115 constituting the compression element 106 is formed with a substantially cylindrical compression chamber 116 extending in the horizontal direction in the drawing, and a main bearing 117 extending substantially downward at right angles to the compression chamber 116 is provided. It has been. The main bearing 117 is provided with a shaft hole 117a (FIG. 2) through which the main shaft portion 111 of the shaft 110 passes.

  Further, a piston 118 is inserted into the compression chamber 116 of the cylinder block 115 so as to be slidable back and forth. One end of the piston 118 is connected to the shaft 110 by a connecting mechanism 119 in which a piston pin 120 provided on the piston 118 is rotatably passed and an eccentric shaft 113 is rotatably passed through the other end. .

On the upper end surface of the main bearing 117 in the cylinder block 115, in a state where the shaft 110 passes through the shaft hole 117a, a load in the vertical direction due to the weight of the rotor 104 and the shaft 110, and a load accompanying a compression action of the piston 118 described later. A thrust surface (corresponding to a thrust receiving portion of the present invention) 121 that supports a load in the vertical direction due to the influence of the above is provided. The thrust surface 121 constitutes a thrust sliding portion by directly sliding with the lower surface of the flange portion 112.

  The thrust surface 121 is formed in a substantially perfect circle as shown in FIG. 2 when viewed from above, and its center C has a predetermined dimension in a direction restricted to the center c of the shaft hole 117a (the direction opposite to the compression chamber 116). The position is shifted and eccentric.

  That is, the thrust surface 121 is formed so that its area gradually increases in the direction away from the compression chamber 116 as the thrust width 124 increases in the direction away from the compression chamber 116.

  Further, the thrust surface 121 has a region on the side where the vertical load F2 is applied due to the influence of the repulsive load F1 accompanying the compression action of the piston 118, that is, a region far from the compression chamber 116, a side closer to the compression chamber 116. The surface is inclined so as to be lower than the region.

  An oil groove 127 extending in the axial direction of the compression chamber 116 (diameter direction of the shaft hole 117a) is provided at a position closest to the compression chamber 116 on the thrust surface 121. By forming the oil groove 127, the lubricating oil pumped up by the oil supply mechanism 114 and passed through the oil supply groove 114a lubricates mainly the thrust sliding portion formed by the thrust surface 121 and the flange portion 112.

  Further, by providing the oil groove 127 at a position closest to the compression chamber 116, an area that slides with the flange portion 112 of the shaft 110 is ensured in a region of the thrust surface 121 far from the compression chamber 116.

  Further, the thrust surface 121 is subjected to nitriding treatment, ceramic coating such as CrN, TiN, etc. by a well-known method, and is processed into a surface with low friction and high hardness.

  The electric element 105 is a concentrated winding type electric element 105 in which windings are concentratedly wound on a tooth portion (not shown) provided in the core of the stator 103. As shown in FIG. 4, the stator 103 is arranged such that the magnetic center 126 of the rotor of the rotor 104 is shifted downward by a predetermined dimension t with respect to the magnetic center 125 of the stator of the stator 103 constituting the electric element 105. And the rotor 104 is arranged.

  Furthermore, as is well known, the electric element 105 can be operated at different rotational speeds by inverter control, and the maximum rotational speed is set to 80 Hz (usually 60 Hz).

  The operation of the hermetic compressor configured as described above will be described below.

  When the electric element 105 is energized, the rotor 104 rotates the shaft 110, and accordingly, the rotational movement of the eccentric shaft portion 113 is transmitted to the piston 118 via the coupling mechanism 119. As a result, the piston 118 reciprocates within the compression chamber 116.

  Due to the movement of the piston 118, the refrigerant gas is sucked into the compression chamber 116 from a cooling system (not shown), compressed, and then discharged to the cooling system again.

As the shaft 110 rotates, a vertical load F3 due to the weight of the rotor 104 and the shaft 110 acts on the entire thrust surface 121 formed on the upper end surface of the cylinder block 115 as shown in FIG. At the same time, a vertical load (component force) F2 due to the influence of the repulsive load F1 accompanying the compression action of the piston 118 acts locally. Therefore, this load F2 is caused by a sliding loss and a sliding loss due to the size of the contact area between the lower surface of the flange portion 112 and the thrust surface 121 in direct sliding between the lower surface of the flange portion 112 provided on the shaft 110 and the thrust surface 121. It will affect the surface pressure.

  Next, the vertical load F2 due to the influence of the repulsive load F1 of the piston 118 applied locally on the thrust surface 121 will be described with reference to FIGS.

  The repulsive load F1 acting on the piston 118 is governed by the pressure in the compression chamber 116 and the inner diameter of the compression chamber 116, and becomes maximum in the vicinity of 330 deg in the latter half of the compression stroke, as shown in FIG. 110 is greatly affected.

  In the latter half of the compression stroke in which the maximum repulsive load F1 is generated, the eccentric shaft portion 113 is positioned on the compression chamber 116 side, and the repulsive load F1 acting on the piston 118 acts on the eccentric shaft portion 113 via the coupling mechanism 119.

  Further, since a clearance of about 10 to 30 μm is set for the diameter of the main shaft portion 111 of the shaft 110 and the diameter of the shaft hole 117 a of the main bearing 117, the shaft 110 is inclined. Along with this inclination, a repulsive load F1 acting on the eccentric shaft portion 113 causes a load F2 in the vertical direction of the repulsive load F1 to act on the thrust surface 121 as a component force in a region substantially opposite to the compression chamber 116.

  Therefore, a vertical load F3 due to the weight of the rotor 104 and the shaft 110 acts on the entire thrust surface 121, and a vertical direction due to the influence of the repulsive load F1 is applied to a region substantially opposite to the compression chamber 116. The load F2 acts.

  Here, by shifting the position of the center c of the shaft hole 117a and the position of the center C of the thrust surface 121 by a predetermined dimension, the thrust width 124 forming the thrust surface 121 becomes non-uniform throughout.

  That is, the thrust width 124 of the region on the side (the side far from the compression chamber 116) that receives the load F2 in the vertical direction due to the influence of the repulsive load F1 accompanying the compression action of the piston 118 is locally secured, and the opposite side ( By reducing the thrust width 124 on the side close to the compression chamber 116, it is possible to suppress an increase in surface pressure due to the vertical load F2 due to the influence of the repulsive load F1 acting on the piston 118 locally.

  As a result, the sliding loss of the thrust sliding portion formed by the lower surface of the flange portion 112 and the thrust surface 121 can be reduced. Further, by preventing an increase in the surface pressure on the side receiving the vertical load F2 due to the influence of the repulsive load F1 acting on the piston 118 locally, by reducing uneven wear of the thrust surface 121, a hermetic compressor Efficiency and reliability can be improved.

  Further, since the oil groove 127 is provided on the thrust surface 121, the amount of oil supplied from the oil groove 127 to the thrust surface 121 can be increased, and more lubricating oil 102 lubricates the sliding portion of the thrust surface 121. . Further, the oil groove 127 is formed on the thrust surface 121 on the opposite side to the side on which the vertical load F2 due to the influence of the repulsive load F1 due to the compression action of the piston 118 applied locally, that is, in the region where the thrust width 124 is small. As a result, it is possible to secure a sliding area on the side where the surface pressure acts greatly (area to be used for sliding), and to prevent an increase in the surface pressure. As a result, the lubrication state of the sliding portion of the thrust surface 121 can be improved, and the reliability of the hermetic compressor can be further improved.

Further, since the thrust surface 121 is subjected to nitriding treatment, ceramic coating such as CrN, TiN, etc., it is a surface with low friction and high hardness, and sliding resistance of the contact surface between the lower surface of the flange portion 112 and the thrust surface 121. Can be further reduced. Therefore, it is possible to improve the efficiency by further reducing the sliding loss of the thrust sliding portion, and to improve the wear resistance of the thrust sliding portion by increasing the surface hardness of the thrust surface 121.

  Further, by the low friction and high hardness processing of the thrust surface 121, the area acting on the sliding of the thrust surface 121 as a whole can be further reduced, and the friction can be further reduced.

  Further, in the thrust surface 121, the region on the side where the vertical load F2 due to the influence of the repulsive load F1 accompanying the compression action of the piston 118 acts is inclined so as to be lower than the region near the compression chamber 116. Thus, the lower surface of the flange portion 112 can be brought into contact with the entire thrust surface 121 as a whole. As a result, it is possible to further avoid contact with the thrust sliding portion, to prevent a local increase in surface pressure, and to suppress uneven wear of the thrust sliding portion.

  On the other hand, in the electric element 105, the rotor 104 is disposed so that the relative position of the magnetic center 126 of the rotor is shifted downward with respect to the magnetic center 125 of the stator. The force which pulls up the fixed shaft 110 acts. As a result, the vertical load due to the weight of the rotor 104 and the shaft 110 during rotation is reduced, and the surface pressure of the thrust surface 121 is reduced, so that higher reliability can be obtained.

  In the first embodiment, the configuration in which the compression element 106 is disposed above the electric element 105 has been described. However, the hermetic compressor having the configuration in which the compression element 106 is disposed below the electric element 105 is described. The same action and effect can be expected.

(Embodiment 2)
FIG. 6 is a longitudinal sectional view of a compression element portion of the hermetic compressor according to the second embodiment of the present invention. FIG. 7 is an exploded perspective view of the main part of the compression element portion of the hermetic compressor. The overall configuration of the hermetic compressor uses the description of FIG. 1 and the description of the first embodiment, and here, the configuration and operation different from those of the first embodiment will be mainly described. Therefore, the same constituent elements as those of the first embodiment will be described with the same reference numerals.

  6 and 7, the configuration that is significantly different from the first embodiment is a portion corresponding to the thrust surface 121 described in the first embodiment.

  That is, in the second embodiment, a concave portion 200 having a predetermined depth is provided so as to surround the shaft hole 117a on the upper portion (on the compression element 106 side) of the main bearing 117 constituting the cylinder block 115, and the concave portion 200 has an annular shape. The thrust bearing (corresponding to the thrust receiving portion of the present invention) 210 is greatly different from that of the first embodiment.

  The concave portion 200 is formed in a substantially perfect circle, and the peripheral portion of the shaft hole 117a is used as the support surface 201 of the thrust bearing 210. The area of the support surface 201 is such that the region opposite to the compression chamber 116 gradually increases. Is formed. A small recess 202 extending outward is provided at a part of the periphery of the recess 200.

  The thrust bearing 210 is formed to have a substantially circular outer shape, and when fitted into the recess 200, the bearing surface 213 is set to a thickness that slightly protrudes from the recess 200 in the axial direction of the shaft hole 117a. The hole 211 is formed such that its axis coincides with the axis c1 of the shaft hole 117a. Further, a convex portion 212 that fits into the small concave portion 202 provided in the concave portion 200 is provided on a part of the outer periphery of the thrust bearing 210.

  Therefore, the thrust bearing 210 is formed so that the bearing surface 213 has an area (thrust width 215) in the direction opposite to the compression chamber 116 gradually increased in the same manner as the recess 200, and the small recess 202 The rotation is prevented by the fitting of the convex portion 212.

  Also, at least the bearing surface 213 of the thrust bearing 210 is subjected to a nitriding treatment, a ceramic coating such as CrN, TiN, etc. by a well-known method as in the first embodiment, and is processed into a surface with low friction and high hardness. Yes.

  Further, the bearing surface 213 has a region farther from the compression chamber 116 than a region closer to the compression chamber 116 by adjusting the thickness dimension of the thrust bearing 210 or by processing the support surface 201 of the recess 200. Inclined to be lower.

  An oil groove 214 having a function similar to that of the oil groove 127 of the first embodiment is provided in a part of the bearing surface 213 of the thrust bearing 210 in the diameter direction of the through hole 211. In the second embodiment, the oil groove 214 is provided at a position closest to the compression chamber 116 on the bearing surface 213.

  By forming the oil groove 214, the lubricating oil pumped up by the oil supply mechanism 114 and passed through the oil supply groove 114a lubricates mainly the thrust sliding portion formed by the bearing surface 213 and the flange portion 112.

  In the above configuration, the rotor 104 is rotated by energization of the electric element 105, and the compression element 106 is operated accordingly.

  As a result, as described in the first embodiment, the refrigerant gas is sucked into the compression chamber 116 from the cooling system (not shown), compressed, and then discharged to the cooling system again.

  Also in the second embodiment, as the shaft 110 rotates, a vertical load F3 due to the weight of the rotor 104 and the shaft 110 acts on the entire surface of the thrust bearing 21 of the main bearing 117 as shown in FIG. In addition, a vertical load F2 (component force) due to the influence of the repulsive load F1 accompanying the compression action of the piston 118 acts locally.

  Therefore, the load F2 is determined by the size of the contact area between the lower surface of the flange portion 112 and the bearing surface 213 in direct sliding between the lower surface of the flange portion 112 provided on the shaft 110 and the bearing surface 213 of the thrust bearing 210. Although the sliding loss and the surface pressure are affected, as described in the first embodiment, the side receiving the vertical load F2 due to the influence of the repulsive load F1 accompanying the compression action of the piston 118 locally ( By ensuring a large area (thrust width 215) on the region far from the compression chamber 116 and reducing the area (thrust width 215) on the opposite side (side closer to the compression chamber 116), The increase in the surface pressure due to the vertical load F2 due to the influence of the repulsive load F1 acting on the piston 118 can be suppressed.

  As a result, as in the first embodiment, the sliding loss of the thrust sliding portion formed by the lower surface of the flange portion 112 and the bearing surface 213 of the thrust bearing 210 can be reduced. Further, by preventing an increase in surface pressure on the side receiving the vertical load F2 due to the influence of the repulsive load F1 acting on the piston 118 locally, uneven wear of the bearing surface 213 is reduced, and the efficiency of the hermetic compressor is reduced. Improvement and reliability can be improved.

Further, since the oil groove 214 is provided on the bearing surface 213 of the thrust bearing 210, the oil groove 214 is provided.
Thus, the amount of oil supplied to the bearing surface 213 can be increased, and more lubricating oil 102 lubricates the sliding portion of the bearing surface 213. Further, the oil groove 214 is formed on the bearing surface 213 on the opposite side to the side where the vertical load F2 due to the influence of the repulsive load F1 due to the compression action of the piston 118 applied locally, that is, in the region where the thrust width 215 is small. As a result, it is possible to secure a sliding area on the side where the surface pressure acts greatly (area to be used for sliding), and to prevent an increase in the surface pressure. As a result, the lubrication state of the sliding portion of the bearing surface 213 of the thrust bearing 210 can be improved, and the reliability of the hermetic compressor can be further improved.

  Furthermore, the bearing surface 213 has a surface with low friction and high hardness due to the nitriding treatment and the ceramic coating of CrN, TiN, etc., and the contact surface between the lower surface of the flange portion 112 and the bearing surface 213. The sliding resistance can be further reduced. Therefore, the sliding loss of the thrust sliding portion can be further reduced to improve the efficiency, and the wear resistance of the thrust sliding portion can be improved by increasing the surface hardness of the bearing surface 213.

  Further, by the low friction and high hardness processing of the bearing surface 213 of the thrust bearing 210, the area acting on the sliding of the entire bearing surface 213 in the thrust bearing 210 can be further reduced, and the friction can be further reduced.

  Further, on the bearing surface 213 of the thrust bearing 210, a region on the side where the vertical load F2 due to the influence of the repulsive load F1 due to the compression action of the piston 118 acts, that is, a region far from the compression chamber 116, By inclining the bearing surface 213 so as to be lower than the region closer to 116, as in the first embodiment, it is possible to further avoid the contact of the thrust sliding portion and increase the local surface pressure. This can prevent uneven wear of the thrust sliding portion.

  Further, since the thrust bearing 210 is a separate part from the main bearing 117, the thrust bearing 210 is processed separately from the main bearing 117. Therefore, nitriding treatment applied to the bearing surface 213, ceramic coating processing such as CrN, TiN or the like, or surface processing in which the surface is inclined so as to gradually decrease as the distance from the compression chamber 116 side becomes easy.

  As a result, the degree of ceramic coating can be adjusted and set easily and inexpensively, and the tilting of the bearing surface 213 is easy, so it can be applied to compressors with different capacities. The versatility of can be improved.

  In the second embodiment, the compression element 106 can be similarly applied to a hermetic compressor having a configuration in which the electric element 105 is disposed below the electric element 105, and similar effects can be expected.

  As described above, the hermetic compressor according to the present invention reduces the sliding loss of the thrust part and obtains high reliability, and thus can be applied to refrigeration equipment such as an air conditioner and a freezer / refrigerator. .

DESCRIPTION OF SYMBOLS 101 Sealed container 102 Lubricating oil 103 Stator 104 Rotor 105 Electric element 106 Compression element 110 Shaft 111 Main shaft part 112 Flange part 113 Eccentric shaft part 115 Cylinder block 116 Compression chamber 117 Main bearing 117a Shaft hole 118 Piston 119 Connecting mechanism 121 Thrust surface (Thrust receiving part)
125 Magnetic Center of Stator 126 Magnetic Center of Rotor 127 Oil Groove 210 Thrust Bearing (Thrust Receiver)
214 Oil groove

Claims (6)

Lubricating oil is stored in a sealed container, and an electric element having a stator and a rotor and a compression element driven by the electric element are accommodated, and the compression element is formed via a main shaft portion and a flange portion. A shaft having the eccentric shaft portion fixed to the rotor, a cylinder block having a cylindrical compression chamber, a piston reciprocating in the compression chamber, the piston and the eccentric shaft portion. The connecting mechanism is connected to the cylinder block and includes a main bearing that supports the main shaft portion of the shaft. A thrust receiving portion is provided to support a vertical load due to the weight of the child and the shaft and a vertical load of a repulsive load accompanying the compression action of the piston. The surface flange portion abuts the shaft, the hermetic compressor which is formed such that the area on the side remote from the compression chamber is greater than the side close to the compression chamber. 2. The hermetic compressor according to claim 1, wherein an oil groove that communicates a shaft hole through which the main shaft portion passes and an outer peripheral portion of the bearing is provided on a surface of the thrust receiving portion on which the flange portion of the shaft abuts. 3. The hermetic compressor according to claim 1, wherein a surface of the thrust receiving portion with which the flange portion of the shaft abuts is inclined so as to gradually decrease as the distance from the compression chamber side increases. The hermetic compressor according to any one of claims 1 to 3, wherein a ceramic coating such as nitriding treatment, CrN, or TiN is applied to a surface of a surface of the thrust receiving portion on which the flange portion of the shaft contacts. The hermetic compressor according to any one of claims 1 to 4, wherein the thrust receiving portion is configured by a part different from the main bearing. The hermetic compressor according to any one of claims 1 to 5, wherein the electric element is configured such that a position of a magnetic center of a rotor is downward with respect to a magnetic center of the stator.