JP2009041393A - Sealed electric compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed electric compressor that prevents an abnormal noise generated between a piston and a connecting rod, and excels in quietness. <P>SOLUTION: By preparing an annular shock-absorbing material 131 between a piston 101 and a connecting rod 115, a gap is formed between the piston 101 and the connecting rod 115. Thus, when the connecting rod 115 moves up-and-down to generate an impact due to the intermittent contact, the shock-absorbing material 131 becomes a cushion to absorb the impact, and thereby reducing the abnormal noise generated by the impact transmitting to the compressor cylinder. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a connecting device for a piston and a connecting rod of a hermetic electric compressor, and more particularly to a shock absorber provided between the piston and the connecting rod.

  2. Description of the Related Art Conventionally, there is a structure including a U washer for a structure of a connecting portion between a piston and a connecting rod of a hermetic electric compressor (see, for example, Patent Document 1).

  Hereinafter, the conventional hermetic electric compressor will be described with reference to the drawings.

  FIG. 13 is an assembly perspective view of a connecting device in a conventional hermetic electric compressor, FIG. 14 is a cross-sectional view of a main part of the conventional connecting device, and FIG. 15 is an enlarged cross-sectional view of a main part of the conventional connecting device.

  13 to 15, the piston 1 has a hollow portion 3 therein, the piston 1 has a through hole 5 penetrating in the diameter direction, and from the end portion 33 of the piston 1 toward the center of the through hole 5. A locking pin through hole 7 is provided. The piston pin 9 is hollow inside and has a locking pin through hole 11 provided in the radial direction at one end thereof. One end of the connecting rod 15 is inserted into the hollow portion 3 and has a small end portion 19 provided with a small end hole 17 through which the piston pin 9 passes, and the other end is connected to a drive device (not shown) or the like. The large end portion 21 is provided. The U washer 23 is U-shaped and has a piston pin through hole 25 in each of its arms, and the U washer 23 is bent inward in the vicinity of the intermediate portion 27 of the piston pin through hole 25 so that the U washer is free. The end portion 29 is bent outward with a larger curvature than the intermediate portion 27.

  In the above configuration, the coupling device 35 between the piston 1 and the connecting rod 15 will be described. First, the U washer 23 and the small end portion 19 of the connecting rod 15 are inserted into the hollow portion 3 of the piston 1 so that the through hole 5, the piston pin through hole 25, and the small end hole 17 of the piston 1 are aligned coaxially. Then, the piston pin 9 is inserted into the through hole 5, the piston pin through hole 25 and the small end hole 17.

  The small end portion 19 and the inner wall surface 37 of the hollow portion 3 of the piston 1 are separated by the interposition of the U washer 23.

  By inserting the piston pin 9, the U washer 23 and the connecting rod 15 are prevented from being removed from the piston 1, and the small end portion 19 of the connecting rod 15 can swing around the axis of the piston pin 9.

  Next, the respective positions of the locking pin through hole 7 of the piston 1 and the locking pin through hole 11 of the piston pin 9 are matched, and the locking pin 13 is inserted into the locking pin through hole 7 and the locking pin through hole 11.

  By inserting the locking pin 13, the relative rotation of the piston 1 and the piston pin 9 is stopped.

  In the connecting device 35 between the piston 1 and the connecting rod 15 configured as described above, the rotational motion of the drive device (not shown) is converted into the reciprocating motion of the piston 1, and at this time, the small end portion 19 of the connecting rod 15 Swing motion is performed about the piston pin 9 axis.

The U washer 23 supports the small end portion 19 of the connecting rod 15 at an appropriate position by a curvature shape in the vicinity of the piston pin through hole 25, and suppresses the generation of noise due to the contact between the small end portion 19 and the U washer 23. is doing.
JP 2002-243038 A

  However, in the above-described conventional configuration, the U washer 23 is deformed when the hermetic electric compressor is assembled or when the hermetic electric compressor is operated, and a gap is generated between the small end portion 19 of the connecting rod 15 and the U washer 23. In this case, the small end portion 19 of the connecting rod 15 can move up and down in the axial direction of the small end hole 17, and the small end portion 19 of the connecting rod 15, the U washer 23, and the hollow portion 3 of the piston 1 are intermittently connected. There is a problem that an impact is generated as a vibration in contact with the surface and abnormal noise is generated.

  The present invention solves the above-described conventional problems, and a cushioning material that attenuates vibration is interposed between the end surface of the small end of the connecting rod and the inner wall surface of the piston hollow portion, so that there is no abnormal noise and the sealing is highly quiet. It aims at providing a type electric compressor.

  In order to solve the above-described conventional problems, the hermetic electric compressor according to the present invention has a buffer material for damping vibration interposed between the end surface of the small end of the connecting rod and the inner wall surface of the piston hollow portion. Even if the piston, U washer, and the small end of the connecting rod contact each other intermittently and an impact is generated as a vibration, the cushioning material acts as a cushion and has the effect that the impact can be attenuated.

  In the hermetic electric compressor according to the present invention, a shock absorbing material that attenuates vibration is interposed between the end surface of the small end of the connecting rod and the inner wall surface of the piston hollow portion. A compressor can be provided.

  The invention according to claim 1 of the present invention includes a cylinder that forms a compression chamber, a piston that is fitted in the cylinder and has a hollow portion, and a piston pin that passes through the hollow portion and is fixed to the piston. A shaft having a main shaft and an eccentric shaft, and a connecting rod provided with a small end hole fitted into the piston pin and a large end hole fitted into the eccentric shaft at the small end portion and the large end portion, respectively. A cushioning material that attenuates vibration is interposed between the end surface of the small end portion and the inner wall surface of the hollow portion, and a gap is generated between the small end portion of the connecting rod and the inner wall surface of the piston. Even if they are intermittently contacted with each other and the shock is generated, the cushioning material becomes a cushion, the shock can be attenuated, and there can be provided a hermetic electric compressor with no abnormal noise and high quietness.

  The invention according to claim 2 is the invention according to claim 1, wherein the cushioning material is made of polytetrafluoroethylene, and since the cushioning material has a small coefficient of friction and excellent wear resistance, In addition to the effect of the first aspect of the invention, it is possible to further reduce the loss associated with the swinging of the connecting rod small end portion and the piston inner wall surface, and to obtain high efficiency while ensuring reliability.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein an elastic washer formed by bending the leaf spring material is disposed between the cushioning material and the inner wall surface of the hollow portion. Therefore, it is possible to suppress the small end portion of the connecting rod from moving up and down in the axial direction of the small end hole, and in addition to the effect of the invention according to claim 1 or 2, there is no abnormal noise and high silence. Sex can be obtained.

  The invention according to claim 4 is the invention according to claim 1, wherein the cushioning material is formed by bending a leaf spring material, and an elastic washer is coated with polytetrafluoroethylene. It is not necessary to change the assembly by simply applying the coating to the washer, and in addition to the effect of the invention described in claim 1, high silence can be obtained at low cost.

  The invention according to claim 5 is the invention according to claim 1, wherein the cushioning material is formed by coating polytetrafluoroethylene on at least one of the end surface of the small end portion of the connecting rod and the inner wall surface of the hollow portion of the piston. Since it is not necessary to use a washer, the number of parts is reduced, and the efficiency of the assembly work is improved, in addition to the effect of the invention according to claim 1, the assemblability can be further improved at a lower cost. .

  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)
1 is a cross-sectional view of a hermetic electric compressor according to Embodiment 1 of the present invention, FIG. 2 is an assembled perspective view of a coupling device according to the same embodiment, and FIG. 3 is a schematic diagram of the coupling device according to the same embodiment. FIG. 4 is a partial cross-sectional view, and FIG. 4 is an enlarged cross-sectional view of a main part of the coupling device in the same embodiment.

  In FIG. 1, the compressor unit 151 and the electric motor unit 153 are elastically supported by a hermetic case 155. In the compressor section 151, the piston 101 reciprocates in the cylinder 159 through the connecting rod 115 connected to the eccentric shaft 157 a of the shaft 157 having the main shaft 157 b, and the refrigerant gas is compressed in the compression chamber 161. The electric motor unit 153 includes a stator 163 and a rotor 165.

  2, 3, and 4, the piston 101 has a hollow portion 103 inside, the piston 101 has a through hole 105 that penetrates in the diameter direction, and the center of the through hole 105 from the end 133 of the piston 101. A locking pin through hole 107 is provided toward the end. The piston pin 109 is hollow inside and has a locking pin through-hole 111 provided in the radial direction at one end thereof.

  One end of the connecting rod 115 is inserted into the hollow portion 103 and has a small end portion 119 provided with a small end hole 117 through which the piston pin 109 passes, and the other end is connected to the eccentric shaft 157a. It has a large end 121 provided with a hole 120.

  The buffer material 131 is annular and is made of polytetrafluoroethylene, and is inserted between the piston 101 and the connecting rod 115.

  In the above configuration, the assembly of the coupling device 135 of the piston 101 and the connecting rod 115 will be described.

  First, the buffer material 131 and the small end portion 119 of the connecting rod 115 are inserted into the hollow portion 103 of the piston 101, and the through hole 105, the buffer material 131, and the small end hole 117 of the piston 101 are aligned coaxially. Then, the piston pin 109 is inserted into the through hole 105, the buffer material 131 and the small end hole 117.

  The insertion of the piston pin 109 prevents the buffer material 131 and the connecting rod 115 from coming off the piston 101, and the small end portion 119 of the connecting rod 115 can swing around the axis of the piston pin 109.

  Next, the positions of the locking pin through hole 107 of the piston 101 and the locking pin through hole 111 of the piston pin 109 are matched, and the locking pin 113 is inserted into the locking pin through hole 107 and the locking pin through hole 111.

  By inserting the locking pin 113, the relative rotation of the piston 101 and the piston pin 109 is stopped.

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

  When the stator 163 is energized, the rotor 165 rotates with the shaft 157, and the eccentric shaft 157a moves eccentrically accordingly. In the coupling device 135 of the piston 101 and the connecting rod 115, the eccentric motion of the eccentric shaft 157a is converted into the reciprocating motion of the piston 101, and the piston 101 performs a predetermined compression operation for compressing the suction gas in the cylinder 159.

  At this time, the small end portion 119 of the connecting rod 115 performs a swinging motion about the axis of the piston pin 109.

  Here, in the present embodiment, since the annular cushioning material 131 is inserted in the gap between the small end portion 119 of the connecting rod 115 and the inner wall surface 137 of the hollow portion 103 of the piston 101, Even if the small end portion 119 of the connecting rod 115 tries to contact intermittently, the cushioning material 131 acts as a cushion to prevent contact, and the impact at that time can be attenuated.

  Therefore, abnormal noise caused by the coupling device 135 of the piston 101 and the connecting rod 115 does not occur, and a sealed electric compressor with high silence can be provided.

  Furthermore, by using polytetrafluoroethylene having excellent wear resistance as the annular cushioning material 131, loss due to swinging between the small end portion 119 of the connecting rod 115 and the inner wall surface 137 of the hollow portion 103 of the piston 101 is further reduced. And high efficiency can be obtained while ensuring reliability.

(Embodiment 2)
FIG. 5 is a cross-sectional view of the hermetic electric compressor according to the second embodiment of the present invention, FIG. 6 is an assembly perspective view of the coupling device according to the same embodiment, and FIG. 7 is a main part of the coupling device according to the same embodiment. FIG. 8 is an enlarged sectional view of a principal part of the coupling device in the same embodiment.

  In FIG. 5, the compressor unit 351 and the electric motor unit 353 are elastically supported by the sealed case 355. In the compressor unit 351, the piston 301 reciprocates in the cylinder 359 through the connecting rod 315 connected to the eccentric shaft 357 a of the shaft 357 having the main shaft 357 b, and the refrigerant gas is compressed in the compression chamber 361. The electric motor unit 353 includes a stator 363 and a rotor 365.

  6, 7, and 8, the piston 301 has a hollow portion 303 inside, the piston 301 has a through hole 305 that penetrates in the diameter direction, and the center of the through hole 305 from the end 333 of the piston 301. A locking pin through-hole 307 is provided toward the end. The piston pin 309 is hollow inside and has a locking pin through hole 311 provided in the radial direction at one end thereof.

  One end of the connecting rod 315 is inserted into the hollow portion 303 and has a small end portion 319 provided with a small end hole 317 through which the piston pin 309 passes, and the other end is connected to the eccentric shaft 357a. It has a large end 321 provided with a hole 320.

  The U washer 323, which is a washer, has a U-shape, and each arm has a piston pin through hole 325. The U washer 323 is bent inward in the vicinity of the intermediate portion 327 of the piston pin through hole 325, The U washer free end 329 is bent outward with a larger curvature than the intermediate portion 327. Further, the U washer 323 is coated with polytetrafluoroethylene.

  In the above configuration, the assembly of the coupling device 335 for the piston 301 and the connecting rod 315 will be described.

  First, the U washer 323, the buffer material 331, and the small end portion 319 of the connecting rod 315 are inserted into the hollow portion 303 of the piston 301, and the through hole 305, the piston pin through hole 325, and the small end hole 317 of the piston 301 are coaxially arranged. To align. Then, the piston pin 309 is inserted into the through hole 305, the piston pin through hole 325, and the small end hole 317.

  The small end portion 319 and the inner wall surface 337 of the hollow portion 303 of the piston 301 are separated by the interposition of the U washer 323.

  By inserting the piston pin 309, the U washer 323, the buffer material 331, and the connecting rod 315 are configured not to be detached from the piston 301, and the small end portion 319 of the connecting rod 315 can swing around the axis of the piston pin 309. It becomes.

  Next, the positions of the locking pin through hole 307 of the piston 301 and the locking pin through hole 311 of the piston pin 309 are made to coincide with each other, and the locking pin 313 is inserted into the locking pin through hole 307 and the locking pin through hole 311.

  By inserting the locking pin 313, the relative rotation of the piston 301 and the piston pin 309 is stopped.

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

  When the stator 363 is energized, the rotor 365 rotates with the shaft 357, and the eccentric shaft 357a moves eccentrically accordingly. In the coupling device 335 of the piston 301 and the connecting rod 315, the eccentric motion of the eccentric shaft 357a is converted into the reciprocating motion of the piston 301, and the piston 301 performs a predetermined compression operation for compressing the suction gas in the cylinder 359.

  At that time, the small end portion 319 of the connecting rod 315 performs a swinging motion about the axis of the piston pin 309.

  Here, in the present embodiment, since the cushioning material 331 is inserted between the small end portion 319 of the connecting rod 315 and the inner wall surface 337 of the hollow portion 303 of the piston 301, a gap is generated, and the piston 301 and Even if the small end portion 319 of the connecting rod 315 tries to contact intermittently, the cushioning material 331 acts as a cushion to prevent contact, and the impact at that time can be attenuated.

  Therefore, abnormal noise is not generated due to the coupling device 335 of the piston 301 and the connecting rod 315, and a hermetic electric compressor with high silence can be provided.

  Further, by arranging a U washer 323 having elasticity formed by curving the leaf spring material between the buffer material 331 and the inner wall surface 337 of the hollow portion 303 of the piston 301, the small end portion 319 of the connecting rod 315 is provided. It is possible to suppress the vertical movement of the small end hole 317 in the axial direction, and it is possible to obtain high silence without generating abnormal noise.

  Furthermore, loss due to swinging between the small end portion 319 of the connecting rod 315 and the inner wall surface 137 of the hollow portion 303 of the piston 301 can be reduced, and high efficiency can be obtained while ensuring reliability.

  Further, since the U washer 323 is a conventionally used washer coated with polytetrafluoroethylene, there is no need to change the assembly, and high silence can be obtained at low cost.

(Embodiment 3)
9 is a cross-sectional view of the hermetic electric compressor according to the third embodiment of the present invention, FIG. 10 is an assembly perspective view of the coupling device according to the same embodiment, and FIG. 11 is an essential part of the coupling device according to the same embodiment. FIG. 12 is an enlarged sectional view of a main part of the coupling device according to the embodiment.

  In FIG. 9, the compressor unit 551 and the electric motor unit 553 are elastically supported by the sealed case 555. In the compressor section 551, the piston 501 reciprocates in the cylinder 559 via a connecting rod 515 connected to the eccentric shaft 557a of the shaft 557 having the main shaft 557b, and the refrigerant gas is compressed in the compression chamber 561. The electric motor unit 553 includes a stator 563 and a rotor 565.

  10, 11, and 12, the piston 501 has a hollow portion 503 inside, the piston 501 has a through hole 505 that penetrates in the diameter direction, and the center of the through hole 505 from the end 533 of the piston 501. A locking pin through-hole 507 is provided toward the end. The piston pin 509 is hollow inside and has a locking pin through hole 511 provided in the radial direction at one end thereof.

  One end of the connecting rod 515 is inserted into the hollow portion 503 and has a small end portion 519 provided with a small end hole 517 through which the piston pin 509 passes, and the other end is connected to the eccentric shaft 557a. It has a large end 521 provided with a hole 520.

  Furthermore, at least one of the inner wall surface 537 of the hollow portion 503 of the piston 501 or the end surface of the small end portion 519 of the connecting rod 515 is coated with polytetrafluoroethylene.

  In the above configuration, the assembly of the connecting device 535 for the piston 501 and the connecting rod 515 will be described.

  First, the small end portion 519 of the connecting rod 515 is inserted into the hollow portion 503 of the piston 501, and the through hole 505 and the small end hole 517 of the piston 501 are coaxially aligned. Then, the piston pin 509 is inserted into the through hole 505 and the small end hole 517.

  The insertion of the piston pin 509 prevents the connecting rod 515 from coming out of the piston, and the small end 519 of the connecting rod 515 can swing around the piston pin 509 axis.

  Next, the positions of the locking pin through hole 507 of the piston 501 and the locking pin through hole 511 of the piston pin 509 are made to coincide with each other, and the locking pin 513 is inserted into the locking pin through hole 507 and the locking pin through hole 511.

  By inserting the locking pin 513, the relative rotation of the piston 501 and the piston pin 509 is stopped.

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

  When the stator 563 is energized, the rotor 565 rotates with the shaft 557, and the eccentric shaft 557a moves eccentrically accordingly. In the connecting device 535 between the piston 501 and the connecting rod 515, the eccentric motion of the eccentric shaft 557a is converted into the reciprocating motion of the piston 501, and the piston 501 performs a predetermined compression operation for compressing the suction gas in the cylinder 559.

  At this time, the small end portion 519 of the connecting rod 515 performs a swinging motion about the piston pin 509 axis.

  Here, in the present embodiment, the piston 501 and the small end portion 519 of the connecting rod 515 are intermittently provided in the gap between the small end portion 519 of the connecting rod 515 and the inner wall surface 537 of the hollow portion 503 of the piston 501. Even if an impact occurs due to contact, one of the end surface of the small end portion 519 of the connecting rod 515 or the hollow portion 503 of the piston 501 is coated with polytetrafluoroethylene, so that it becomes a cushion and can attenuate the impact. it can.

  Therefore, abnormal noise is not generated due to the coupling device 535 between the piston 501 and the connecting rod 515, and a hermetic electric compressor with high silence can be provided.

  Furthermore, loss due to swinging of the small end portion 519 of the connecting rod 515 and the inner wall surface 537 of the hollow portion 503 of the piston 501 can be reduced, and high efficiency can be obtained while ensuring reliability.

  Further, since the connecting rod 515 and the piston 501 are formed by coating the conventionally used connecting rod 15 and the piston 1 with polytetrafluoroethylene, there is no need to change the assembly and there is no need to use a washer. Since the number of points is reduced and the efficiency of assembling work is improved, the assembling property can be further improved at a lower cost.

  As described above, since the hermetic electric compressor according to the present invention is provided with a cushioning material, a quiet hermetic electric compressor can be provided. It can be applied to any application using a refrigeration cycle such as a vending machine.

Sectional drawing of the hermetic type electric compressor in Embodiment 1 of this invention Assembly perspective view of coupling device in same embodiment Sectional drawing of the principal part of the coupling device in the embodiment The principal part expanded sectional view of the coupling device in the embodiment Sectional drawing of the hermetic type electric compressor in Embodiment 2 of this invention Assembly perspective view of coupling device in same embodiment Sectional drawing of the principal part of the coupling device in the embodiment The principal part expanded sectional view of the coupling device in the embodiment Sectional drawing of the hermetic electric compressor in Embodiment 3 of this invention Assembly perspective view of coupling device in same embodiment Sectional drawing of the principal part of the coupling device in the embodiment The principal part expanded sectional view of the coupling device in the embodiment Assembly perspective view of coupling device in conventional hermetic electric compressor Sectional view of the main part of a conventional coupling device An enlarged cross-sectional view of the main part of a conventional coupling device

Explanation of symbols

101, 301, 501 Piston 103, 303, 503 Hollow part 109, 309, 509 Piston pin 115, 315, 515 Connecting rod 117, 317, 517 Small end hole 119, 319, 519 Small end part 120, 320, 520 Large end hole 121,321,521 Large end 131,331 Buffer material 137,337,537 Inner wall surface 157,357,557 Shaft 157a, 357a, 557a Eccentric shaft 157b, 357b, 557b Main shaft 159,359,559 Cylinder 161,361 561 Compression chamber 323 U washer (washer)

Claims (5)

  A cylinder forming a compression chamber, a piston fitted in the cylinder and provided with a hollow portion, a piston pin penetrating the hollow portion and fixed to the piston, a shaft having a main shaft and an eccentric shaft, A connecting rod having a small end hole fitted into the piston pin and a large end hole fitted to the eccentric shaft at the small end portion and the large end portion, respectively, an end surface of the small end portion and an inner wall surface of the hollow portion, A hermetic electric compressor with a cushioning material that dampens vibrations.   The hermetic electric compressor according to claim 1, wherein the cushioning material is made of polytetrafluoroethylene.   The hermetic electric compressor according to claim 1 or 2, wherein a washer having elasticity formed by curving the leaf spring material is disposed between the buffer material and the inner wall surface of the hollow portion.   2. The hermetic electric compressor according to claim 1, wherein the cushioning material is formed by bending a leaf spring material and is coated with polytetrafluoroethylene on an elastic washer.   2. The hermetic electric compressor according to claim 1, wherein the buffer material is formed by coating polytetrafluoroethylene on at least one of an end surface of the small end portion of the connecting rod and an inner wall surface of the hollow portion of the piston.

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