JP2014214641A - Hermetic type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hermetic type compressor in which the reliability of sealing performance of a terminal unit is improved, while the terminal unit, which is fixed to a housing, has a raised face and the terminal unit has excellent pressure resistance.SOLUTION: A terminal unit, which closes an opening of a housing, has a terminal pin, a terminal block, and a seal member. The terminal block includes a central part which has a pin insertion hole, a flange part which has a plurality of fastening holes disposed on an outer peripheral side, and a raised face which projects from an inner peripheral side of the flange part in an axial direction of the pin insertion hole toward an inner side of the housing and which has a flange seal surface to abut against a gasket. The central part includes a projection which projects from the flange seal surface toward the inner side of the housing in the axial direction of the pin insertion hole. The seal member extends while exceeding the flange seal surface in the axial direction of the pin insertion hole. An outer end of the seal member is positioned on a side of the housing as compared with a bolt head integrated into one unit with a shaft part or a nut screw-engaged with the shaft part, in the axial direction of the pin insertion hole.

Description

  The present disclosure relates to a hermetic compressor and relates to a hermetic compressor suitable for a scroll compressor.

In the hermetic compressor, a discharge chamber is defined inside a housing, and a compression unit and a drive unit are accommodated. The compression unit is driven by the drive unit, compresses the target gas, and discharges it to the discharge chamber.
The housing is provided with an opening in a region defining the discharge chamber, and the opening is airtightly closed by the terminal unit. The terminal unit has terminal pins extending from the inside of the housing to the outside, and power is supplied to the drive unit through the terminal pins.

For example, in the electric compressor disclosed in Patent Document 1, a pin insertion hole is provided in a terminal board, and a terminal pin is inserted into the pin insertion hole, and is fixedly supported in an insulated state and an airtight state. The terminal board is fastened and fixed to the mounting surface of the housing by a bolt via a gasket.
According to Patent Document 1, according to this electric compressor, even when carbon dioxide is used as the refrigerant gas, the pressure strength is ensured without causing an increase in the size of the terminal pin fixing portion, and the refrigerant gas is surely leaked. Is described as being prevented.

JP 2005-155369 A

  In the electric compressor disclosed in Patent Document 1, the sealing surface of the terminal board located on the housing side is flat, and in order to increase the pressure resistance, when the contact pressure of the sealing surface to the gasket is increased, more It is necessary to fix the terminal board using bolts. However, when the number of bolts is increased, the terminal board is increased in size.

  Therefore, it is conceivable to provide the terminal board with a flat seat protruding toward the housing, and bring the flat seat into contact with the gasket at a high contact pressure. However, when the flat seat is provided, the terminal board bends when the terminal board is tightened with a bolt. Due to this bending, tensile stress acts on the glass sealing member in the pin insertion hole, and the glass sealing member may be broken or peeled off from the inner surface of the pin insertion hole.

  Therefore, at least one embodiment of the present invention provides a hermetic compressor in which the terminal unit fixed to the housing has a flat seat and has excellent pressure resistance, while the reliability of the sealing performance of the terminal unit is improved. The purpose is to provide.

  According to at least one embodiment of the present invention, a housing having an opening surrounded by a housing-side sealing surface in contact with a gasket in a region partitioning the discharge chamber, and disposed in the housing, compresses a target gas and A compression unit that discharges into the discharge chamber; a drive unit that is disposed in the housing and drives the compression unit; and a terminal unit that is fixed to the housing via a gasket and hermetically closes the opening of the housing. The terminal unit is provided integrally with the terminal portion for supplying power to the drive unit, a central portion having a pin insertion hole through which the terminal pin is inserted, and the central portion. A flange portion having a plurality of fastening holes to be inserted on the outer peripheral side, and the pin insertion hole from the inner peripheral side of the flange portion A terminal block including a flat seat having a flange seal surface that protrudes in the axial direction toward the inside of the housing and abuts against the gasket is sealed between the outer periphery of the terminal pin and the inner periphery of the pin insertion hole. A seal member made of glass, and the central portion includes a protruding portion that protrudes from the flange seal surface toward the inside of the housing in the axial direction of the pin insertion hole, In the axial direction of the pin insertion hole, it extends beyond the flange seal surface, and in the axial direction of the pin insertion hole, the outer end of the seal member is a bolt head or the shaft integral with the shaft portion. A hermetic compressor is provided that is located closer to the housing than a nut that is screwed into the portion.

The hermetic compressor of one embodiment is excellent in pressure resistance because the terminal block has a flat seat and the contact pressure between the flange seal surface and the gasket increases.
On the other hand, in this hermetic compressor, the central portion of the terminal block has a protruding portion that protrudes beyond the flange seal surface, the seal member extends beyond the flange seal surface, and the seal member is more than the bolt head or nut. The outer end is located near the flange seal surface.
According to this configuration, since the projecting portion is provided, the seal member can be brought closer to the housing without securing the length of the seal member in the axial direction of the pin insertion hole. Thereby, when the terminal block is bent by the axial force of the fastening member and the pressure of the target gas in the discharge chamber, the tensile stress acting on the seal member is reduced. As a result, cracks in the seal member and peeling of the seal member from the inner periphery of the fastening hole and the outer periphery of the terminal pin are less likely to occur. For this reason, the reliability of the sealing performance of the sealing member is increased.

In one embodiment, the housing has a recess for receiving the flat seat, the housing-side sealing surface is formed by the bottom surface of the recess, and the gasket is surrounded by the peripheral surface of the recess.
In this configuration, since the peripheral surface of the recess surrounds the gasket, the diameter of the gasket does not expand even when the gasket receives the pressure of the target gas in the discharge chamber. As a result, the occurrence of cracks and breaks in the gasket is prevented. As a result, the reliability of the sealing performance of the gasket is increased.

  According to one embodiment of the present invention, there is provided a hermetic compressor in which the terminal unit fixed to the housing has a flat seat and has excellent pressure resistance, while the reliability of the sealing performance of the terminal unit is improved. Is done.

It is sectional drawing which shows the schematic structure of the hermetic compressor of one Embodiment. It is a figure which expands and shows the terminal unit and its periphery of the hermetic compressor of FIG. FIG. 3 is an enlarged view of a region III in FIG. 2. FIG. 3 is a schematic perspective view of a terminal unit in FIG. 2. It is a figure for demonstrating the function of the terminal unit of FIG. It is a figure corresponding to FIG. 3 of the hermetic compressor of other one Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. .

FIG. 1 is a cross-sectional view schematically showing a configuration of a hermetic compressor according to an embodiment of the present invention, and the hermetic compressor is a hermetic scroll compressor. The hermetic compressor is used for compressing a refrigerant such as carbon dioxide gas or ammonia gas, for example.
The hermetic compressor includes a housing 10, and the housing 10 includes, for example, an upper case 12, an intermediate case 14, and a lower case 16 that are welded to each other. The middle case 14 has a cylindrical shape, and the upper case 12 and the lower case 16 have a bowl shape.

  A frame member 18 is fixed inside the middle case 14, and a compression unit 20 is disposed between the frame member 18 and the upper case 12. The compression unit 20 includes a fixed scroll 24 and a turning scroll 26 that form a compression chamber 22 therebetween. As the orbiting scroll 26 orbits with respect to the fixed scroll 24, the process of sucking and compressing the target gas in the compression chamber 22 and discharging it to the discharge chamber 30 is repeated.

  Supply of the target gas to the compression chamber 22 is performed through a suction pipe 28 that passes through the housing 10 and extends to the compression chamber 22, and the target gas compressed in the compression chamber 22 is discharged into a discharge chamber around the compression unit 20. 30 is discharged. The discharge chamber 30 extends over substantially the entire area inside the housing 10, and the outer shape of the discharge chamber 30 is formed by the housing 10.

A discharge pipe 32 is hermetically attached to the housing 10 so as to communicate with the discharge chamber 30, and the target gas in the discharge chamber 30 is discharged to the outside through the discharge pipe 32. During operation of the hermetic compressor, the pressure in the discharge chamber 30 is, for example, in the range of 1.0 MPa to 3.0 MPa in the case of NH ₃ refrigerant.
In the present embodiment, the liquid injection pipe 34 passes through the housing 10 in an airtight manner and extends to the compression chamber 22, and liquid refrigerant for cooling can be supplied to the compression chamber 22.

  In order to turn the orbiting scroll 26 relatively, the fixed scroll 24 is fixed to the frame member 18, the orbiting scroll 26 is connected to the main shaft 36 through the shaft hole of the frame member 18, and the main shaft 36 is a frame. The member 18 is rotatably supported.

  The drive unit 38 that drives the compression unit 20 includes an electric motor disposed between the frame member 18 and the lower case 16, and the electric motor includes a rotor 40 and a stator 42 that are disposed concentrically with the main shaft 36. Have. The rotor 40 is fixed to the main shaft 36. On the other hand, the stator 42 is fixed to the motor frame 44 fixed to the frame member 18.

  In order to supply electric power to the drive unit 38 from the outside, the housing 10 is provided with an opening 48, and the opening 48 is airtightly closed by the terminal unit 50. The opening 48 is provided in a region of the housing 10 that partitions the discharge chamber 30, and is provided in the middle case 14 in the present embodiment.

2 is an enlarged cross-sectional view schematically showing a part of the middle case 14 and the terminal unit 50, FIG. 3 is an enlarged view of a region III in FIG. 2, and FIG. FIG.
As shown in FIGS. 2 to 4, the terminal unit 50 closes the circular opening 48 of the middle case 14 via a rubber gasket 52. The middle case 14 has a flat annular sealing surface (housing side sealing surface) 54 surrounding the opening 48, and the annular gasket 52 is disposed on the housing side sealing surface 54.

  In the terminal unit 50, a metal terminal pin 58 is mounted on a metal terminal block 56 while ensuring airtightness and electrical insulation. In the present embodiment, three rod-shaped terminal pins 58 are provided, and screws are provided on both ends of the terminal pins 58 for wiring connection.

  The terminal block 56 includes a central portion 60, a flange portion 62, and a plane seat 64 that are integrally formed with each other. The central portion 60 has an inner surface 66 on the housing 10 side and an outer surface 68 on the opposite side of the housing 10. The central portion 60 has a plurality of pin insertion holes 70 penetrating itself in the thickness direction of the terminal block 56 (a direction in which the inner surface 66 and the outer surface 68 are separated, hereinafter simply referred to as the thickness direction). The number of pin insertion holes 70 is three corresponding to the number of terminal pins 58.

  The flange portion 62 extends outward from the central portion 60 in the radial direction of the terminal block 56 (a direction orthogonal to the thickness direction of the terminal block 56). A plurality of fastening holes 74 through which a shaft portion of a bolt 72 as a fastening member is inserted are provided on the radially outer side of the flange portion 62. The fastening holes 74 pass through the flange portions 62 in the thickness direction and are provided at intervals in the circumferential direction of the terminal block 56. The bolt 72 may be a single head or a stud bolt.

  The thickness of the flange portion 62 is thinner than the thickness of the central portion 60, and the flange portion 62 is biased toward the outer surface 68 side of the central portion 60 in the thickness direction. The outer surface 76 of the flange portion 62 is flush with the outer surface 68 of the central portion 60, and there is a step between the inner surface 78 of the flange portion 62 and the inner surface 66 of the central portion 60.

  The flat seat 64 is provided at a corner formed by the radially inner side of the flange portion 62 and the central portion 60, and protrudes from the radially inner peripheral side of the flange portion 62 toward the housing 10 in the thickness direction. The flat seat 64 has a flange seal surface 80 that contacts the gasket 52. The flange seal surface 80 has a flat annular shape.

The flange seal surface 80 is located between the inner surface 66 of the central portion 60 and the inner surface 78 of the flange portion 62 in the thickness direction. Accordingly, the central portion 60 includes a protruding portion (inlay portion) 82 that protrudes toward the housing 10 from the flange seal surface 80 in the thickness direction. The outer diameter of the protrusion 82 is slightly smaller than the diameter of the opening 48 of the housing 10, and the protrusion 82 is inserted into the opening 48. The lower limit of the protrusion length L of the protrusion 82 is at least 1 mm, and the upper limit can be appropriately selected. The protrusion length L of the protrusion part 82 is 1 mm or more and 8 mm or less, for example.
The pin insertion hole 70 also penetrates the protruding portion 82.

A seal member 84 made of glass is filled between the inner periphery of the pin insertion hole 70 and the outer periphery of the terminal pin 58. The seal member 84 is in close contact with the inner periphery of the pin insertion hole 70 and the outer periphery of the terminal pin 58, and seals between the inner periphery of the pin insertion hole 70 and the outer periphery of the terminal pin 58.
The seal member 84 extends from the inner surface 66 of the central portion 60 to the approximate center of the pin insertion hole 70 in the axial direction of the pin insertion hole 70. Therefore, the seal member 84 is also filled in the portion of the pin insertion hole 70 extending in the protruding portion 82, and extends beyond the flange seal surface 80.

The outer end of the seal member 84 is located in the pin insertion hole 70 and is located closer to the housing 10 than the outer surface 68 of the central portion 60. In other words, the outer end of the seal member 84 is located closer to the housing 10 than the outer surface 76 of the flange portion 62 with which the head of the bolt 72 abuts in the axial direction of the pin insertion hole 70.
On the other hand, the remaining portion of the pin insertion hole 70 is filled with a protective member 86 made of, for example, silicon rubber.

The hermetic compressor according to the embodiment described above has excellent pressure resistance because the terminal block 56 has the flat seat 64 and the contact pressure between the flange seal surface 80 and the gasket 52 becomes high.
On the other hand, in this hermetic compressor, the central portion 60 of the terminal block 56 has a protruding portion 82 that protrudes from the flange seal surface 80, the seal member 84 extends beyond the flange seal surface 80, and the bolt 72 In the case of a head or stud bolt, the outer end of the seal member 84 is located on the housing 10 side rather than the nut.

  According to this configuration, since the projecting portion 82 is provided, the seal member 84 can be brought closer to the housing 10 without securing the length of the seal member 84 in the axial direction of the pin insertion hole 70. For this reason, as emphasized in FIG. 5, by adopting the flat seat 64, when the terminal block 56 is bent by the axial force of the bolt 72 and the pressure of the target gas in the discharge chamber 30, The tensile stress acting on it is reduced. As a result, in this hermetic compressor, cracks in the seal member 84 and peeling of the seal member 84 from the inner periphery of the pin insertion hole 70 and the outer periphery of the terminal pin 58 hardly occur, and the reliability of the sealing performance of the seal member 84 Becomes higher.

  The present invention is not limited to the above-described embodiment, and includes a form obtained by modifying the above-described embodiment.

FIG. 6 is an enlarged view corresponding to FIG. 3 of a hermetic compressor according to another embodiment, and this hermetic compressor has an annular recess 88 for receiving a flat seat 64 at the outlet of the opening 48. doing. The bottom surface of the recess 88 forms a housing-side sealing surface 54 that contacts the gasket 52, and the peripheral surface of the recess 88 surrounds the gasket 52.
In this configuration, since the peripheral surface of the recess 88 surrounds the gasket 52, the diameter of the gasket 52 does not expand even when the pressure of the target gas in the discharge chamber 30 is received. As a result, the occurrence of cracks and breaks in the gasket 52 is prevented, and the reliability of the sealing performance of the gasket 52 is increased.

Finally, the hermetic compressor of the present invention is not limited to a scroll compressor, and may of course be a screw compressor or a reciprocating compressor. Further, the refrigerant is not limited to NH ₃ and is suitable for use of a high-pressure refrigerant such as CO ₂ . When the high-pressure refrigerant is used, the pressure in the discharge chamber 30 reaches about 10 MPa. Even in this case, the terminal unit 50 can block the opening 48 in an airtight manner.

DESCRIPTION OF SYMBOLS 10 Housing 12 Upper case 14 Middle case 16 Lower case 18 Frame member 50 Terminal unit 52 Gasket 54 Housing side sealing surface 56 Terminal block 58 Terminal pin 60 Center part 62 Flange part 64 Plane seat 70 Pin insertion hole 72 Bolt (fastening member)
74 Fastening hole 80 Flange seal surface 84 Seal member 86 Protection member 88 Recess

Claims (2)

A housing having an opening surrounded by a housing-side sealing surface in contact with the gasket in a region defining the discharge chamber;
A compression unit disposed in the housing and compressing a target gas to be discharged into the discharge chamber;
A drive unit disposed within the housing and driving the compression unit;
A terminal unit fixed to the housing via a gasket and hermetically closing the opening of the housing;
The terminal unit is
Terminal pins for supplying power to the drive unit;
A central portion having a pin insertion hole through which the terminal pin is inserted, a flange portion provided integrally with the central portion, and having a plurality of fastening holes through which shaft portions of fastening members are respectively inserted, and the flange A terminal block including a flat seat having a flange sealing surface protruding from the inner peripheral side of the portion toward the inside of the housing in the axial direction of the pin insertion hole, and contacting the gasket;
A seal member made of glass that seals between the outer periphery of the terminal pin and the inner periphery of the pin insertion hole;
The central portion includes a protruding portion that protrudes from the flange seal surface toward the inside of the housing in the axial direction of the pin insertion hole,
The seal member extends beyond the flange seal surface in the axial direction of the pin insertion hole,
In the axial direction of the pin insertion hole, the outer end of the seal member is located closer to the housing than a bolt head integral with the shaft portion or a nut screwed into the shaft portion. A hermetic compressor. The housing has a recess for receiving the planar seat;
The housing-side sealing surface is formed by the bottom surface of the recess,
The hermetic compressor according to claim 1, wherein the gasket is surrounded by a peripheral surface of the recess.

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