JP2007309238A - Electric compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compressor capable of reducing the cost with less number of components and improving reliability. <P>SOLUTION: The electric compressor is equipped with the following inside a main body casing 3: a compression mechanism part 5 for sucking, compressing, and discharging a refrigerant; a motor 4 for driving the compression mechanism part 5; a liquid storing part 8 for storing a lubricating oil 9 for lubricating a sliding part such as the compression mechanism part 5; a suction passage 23 for sucking the lubricating oil 9 stored in the liquid storing part 8; and a protective device for operating to lower the pressure inside the main body casing 3 when the pressure is higher than a predetermined value. The suction passage 23 is formed integrally with the casing 3 by forming a through hole in an end wall part 3a of the main casing 3 from below and enclosing an opening lower end 23a by a seal member, and as the seal member, the protective device such as a relief valve 50 is used for sealing. The protective device can be provided with less number of components, and the possibility of the refrigerant leaking out can be suppressed by decreasing the number of holes provided in the main body casing 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric compressor used in a vehicle air conditioner and the like, and more particularly to installation of a protection device that protects equipment from abnormal pressure.

  2. Description of the Related Art Conventionally, in a compressor, a protection device such as a relief valve that releases pressure is provided in order to protect from an abnormal high-pressure operation state (see, for example, Patent Document 1).

  FIG. 2 is a cross-sectional view of a conventional compressor. The compressor shown in FIG. 2 is of a type driven by external power through an electromagnetic clutch. The compressor body 101 sucks and discharges refrigerant, and compresses the refrigerant sucked into the compressor body 101. A compressor 102 that drives the compressor 102, and an electromagnetic clutch 104 that transmits power from the outside to the drive shaft 103. A protective device 105 is attached to the compressor body 101. That is, if the protective device 105 is attached to a position where the container is at a high pressure, it is possible to immediately cope with an abnormal pressure.

  In addition, in an oil supply mechanism of an electric compressor, a technique is disclosed in which a passage through which an oil supply pump driven by a drive shaft of an electric motor sucks up lubricating oil from an oil storage chamber is formed integrally with a wall of a container (for example, patent document) 2).

FIG. 3 is a cross-sectional view of a conventional electric compressor. In FIG. 3, a compression mechanism section 113 driven by an electric motor 112 is provided in a container 111, and the rotation of the electric motor 112 is controlled by an inverter device 114 disposed on the upper portion of the container 111. An oil supply pump 116 is configured on the side of the drive shaft 115 of the electric motor 112 opposite to the compression mechanism 113. This oil pump 116 is housed in a space formed by digging the end wall 111 a of the container 111. Lubricating oil accumulates at the bottom of the container 111, and a suction passage 117 is provided in the end wall 111a for the oil pump 116 to suck up the lubricating oil. The suction passage 117 is formed by providing a through hole in the end wall portion 111 a from below to the oil supply pump 116 and sealing the opening lower end portion 117 a with a sealing bolt 118. Thereby, the man-hour in the assembly of the suction passage 117 can be reduced.
JP 2005-155543 A JP 2005-171951 A

  However, when a relief valve is provided in a conventional electric compressor, it is necessary to process a hole for providing the relief valve and two holes for the suction passage, and it is necessary to seal with a bolt and an O-ring. It takes time and the number of parts increases. In addition, there is an increase in the number of places that leak from the sealing surface, which has the problem of reducing costs and hindering high quality.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a compressor that can provide a relief valve with a small number of parts and can further reduce costs and improve reliability.

In order to solve the conventional problems, a compressor according to the present invention includes a compression mechanism portion that sucks, compresses, and discharges refrigerant, a motor that drives the compression mechanism portion, and a slide that includes the compression mechanism portion. A liquid storage part that stores liquid for lubrication of the part, a suction passage that sucks up the liquid stored in the liquid storage part, and operates to lower the pressure in the container when the pressure in the container exceeds a predetermined value And a suction passage is formed integrally by forming a through-hole in the end wall portion of the container from below and sealing the lower end portion of the opening with a seal member, and the seal member uses the protection device. It is composed.

  As a result, the protection device can be provided with a small number of parts, and the possibility of refrigerant leakage can be suppressed.

  The electric compressor of the present invention can satisfy reliability improvement and low cost by reducing the number of parts.

  The present invention stores in a container a reservoir for storing a liquid that is intended to lubricate a sliding mechanism including a compression mechanism that performs suction, compression, and discharge of a refrigerant, an electric motor that drives the compression mechanism, and the compression mechanism. In a compressor comprising a liquid part, a suction passage for sucking up the liquid accumulated in the liquid storage part, and a protection device that operates to lower the pressure in the container when the pressure in the container becomes higher than a predetermined value, the suction passage Is formed integrally by forming a through hole in the end wall of the container from below and sealing the lower end of the opening with a sealing member, and the sealing member is sealed using a protective device such as a relief valve. In addition, the protective device can be provided with a small number of parts, and the number of holes provided in the main body casing can be reduced to suppress the possibility of leakage of the refrigerant.

  As a result, the relief valve can be configured with a small number of parts, thereby reducing the cost and improving the reliability.

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

(Embodiment 1)
FIG. 1 is a cross-sectional view of the electric compressor according to Embodiment 1 of the present invention. FIG. 1 shows one example in the case of a horizontal electric compressor that is installed sideways by a mounting leg 2 around the body of the electric compressor 1, and the electric compressor 1 includes a main body casing 3. An electric motor 4 is housed therein, and a compression mechanism 5 that is fitted or press-fitted into the main casing 3 is driven. The electric motor 4 is driven by an inverter 7 incorporated in an inverter case 6. Further, the main body casing 3 is provided with a liquid storage section 8 for storing a liquid for lubrication of each sliding section including the compression mechanism section 5. The refrigerant to be handled is a gas refrigerant, and a lubricating oil 9 is used as a liquid to be used for lubrication of each sliding portion and a seal of the sliding portion of the compression mechanism portion 5.

  The compression mechanism unit 5 of the electric compressor 1 of the present embodiment is of a scroll type. The compression space 10 formed by meshing the fixed scroll 11 and the orbiting scroll 12 whose blades rise from the fixed end plate 11a and the orbiting end plate 12a, respectively. When the circular orbital motion is performed, the refrigerant 14 returning from the external cycle by changing the volume with movement is sucked, compressed, and discharged to the external cycle to the suction port 15 and the main body casing 3 provided in the inverter case 6. This is performed through the provided discharge port 16.

Hereinafter, the configuration will be described in detail. In FIG. 1, a main bearing member 20 having an oil supply pump 17, an auxiliary bearing 18, an electric motor 4, and a main bearing 19 is disposed from one end wall 3 a side in the axial direction in the main body casing 3. The oil supply pump 17 is accommodated from the outer surface of the end wall portion 3a and is held between the lid body 21 and the pump body 22 that leads to the liquid storage section 8 inside the lid body 21 to form a suction passage. 23 to communicate with the liquid storage unit 8. The auxiliary bearing 18 is supported by the end wall 3a and pivotally supports the side of the drive shaft 13 connected to the oil pump 17. The electric motor 4 is configured such that the stator 4 a is shrink-fitted and fixed to the main body casing 3, or is fixed by the annular member 24, and the drive shaft 13 can be rotationally driven by the rotor 4 b fixed around the drive shaft 13. Yes. An oil supply passage 25 is formed inside the drive shaft 13.

  The main bearing member 20 is fixed by a fixed scroll 11 and a bolt (not shown) and is held by an inverter case 6 fitted to the opening side of the main body casing 3, and the compression mechanism portion 5 side of the drive shaft 13 is held on the main bearing. 19 is pivotally supported. Further, the scroll compressor is configured by sandwiching the orbiting scroll 12 between the main bearing member 20 and the fixed scroll 11. Between the main bearing member 20 and the orbiting scroll 12, a rotation restraining portion for preventing the rotation of the orbiting scroll 12 such as the Oldham ring 26 and causing the circular movement is provided, and the drive shaft 13 is orbited via the eccentric bearing 27. Connected to the scroll 12, the orbiting scroll 12 can be turned on a circular path.

  In the inverter case 6, a suction chamber 28 is formed by airtightly combining a space communicating with the suction port 15 with the fixed end plate 11 a of the fixed scroll 11 using a seal member 11 b. Further, the fixed scroll 11 is provided with a discharge hole 29 and a reed valve 29a, and is opened to the discharge chamber 30 protruding into the suction chamber 28. The discharge chamber 30 communicates with the motor 4 through a communication passage 31 formed by a groove 31 a provided on the outer periphery of the fixed scroll 11 and the main bearing member 20 and an inner peripheral surface of the main casing 3. A through passage 31b is formed in the fixed scroll 11 from the discharge chamber 30 to the groove 31a.

  The inverter 7 includes a circuit board 32 and an electrolytic capacitor (not shown) on the opposite surface of the suction chamber 28 in the partition wall 6 a of the inverter case 6. Further, an IPM (intelligent power module) heat generating component 33 including a switching element having a high heat generation degree is mounted on the circuit board 32 so as to be in thermal contact with the partition wall 6a. The inverter 7 is electrically connected to the electric motor 4 via a compressor terminal 35 connected by a harness connector 34, and is driven by the inverter 7 while monitoring necessary information such as temperature. is there. A cover 36 is provided so as to cover the inverter 7.

  Further, in the first embodiment, the suction passage 23 provided in the end wall portion 3a is provided with a through hole from the lower side to the oil supply pump 17 inside the end wall portion 3a, and the opening lower end portion 23a is sealed by the relief valve 50. Is formed. For the purpose of ensuring safety, the relief valve 50 operates to lower the pressure of the main casing 3 when the pressure of the main casing 3 becomes higher than a predetermined value. The relief valve 50 may be operated by detecting the temperature.

  Based on the above configuration, the operation of the electric compressor in the first embodiment will be described. The electric motor 4 is driven by the inverter 7 and moves the compression mechanism 5 in a circular orbit via the drive shaft 13 and drives the oil supply pump 17. At this time, the compression mechanism unit 5 is supplied with the lubricating oil 9 of the liquid storage unit 8 through the oil supply passage 25 of the drive shaft 13 by the oil supply pump 17 and receives the lubrication and sealing action, and is refrigerated through the suction port 15 provided in the inverter case 6. Inhale the return refrigerant from the cycle. The sucked refrigerant 14 cools the partition wall 6a over a wide range in the space of the suction chamber 28 and exchanges heat with a heat-generating component 33 such as an IPM mounted on the back surface of the partition wall 6a. It flows into the compression space 10 via a not-shown). The refrigerant 14 is compressed in the compression space 10 and discharged from the discharge hole 29 to the discharge chamber 30.

  The refrigerant discharged into the discharge chamber 30 enters the electric motor 4 through the communication passage 31 formed between the groove 31 a provided on the outer peripheral portion of the fixed scroll 11 and the inner peripheral surface of the main casing 3, and In the long process until cooling is discharged from the discharge port 16 of the main casing 3, the refrigerant is accompanied by the separation of the lubricating oil 9 by performing various gas-liquid separations such as collision, centrifugation, and throttling. The auxiliary bearing 18 is also lubricated by a part of the lubricating oil 9. Then, it is discharged out of the main casing 3 through the discharge port 16.

  That is, the liquid storage section 8 and the suction passage 23 in the vicinity where the relief valve 50 is attached are in a high-pressure space due to the compressed refrigerant, and the relief valve 50 immediately operates at an abnormal pressure to ensure safety. be able to.

  And there is no need to process and provide a hole for the relief valve 50 in the main body casing 3 again, the possibility of refrigerant leakage can be suppressed, and a protection device can be configured with a small number of parts. Costs can be reduced and reliability can be improved.

  As described above, the electric compressor according to the present invention can be reduced in cost and reliability with a small number of parts, and thus can be applied to a compressor without a built-in electric motor.

Sectional drawing of the compressor in embodiment of this invention Cross section of a conventional compressor Cross section of a conventional electric compressor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric compressor 3 Main body casing 3a End wall part 4 Electric motor 5 Compression mechanism part 8 Liquid storage part 9 Lubricating oil 11 Fixed scroll 12 Orbiting scroll 13 Drive shaft 14 Refrigerant 23 Suction passage 23a Opening lower end part 50 Relief valve

Claims (1)

In the container, a compression mechanism portion that sucks, compresses and discharges the refrigerant, an electric motor that drives the compression mechanism portion, and a liquid storage portion that stores a liquid for lubricating the sliding portion including the compression mechanism portion. An electric compressor comprising: a suction passage that sucks up the liquid accumulated in the liquid storage part; and a protection device that operates to lower the pressure in the container when the pressure in the container becomes higher than a predetermined value. The suction passage is integrally formed by forming a through hole in the end wall portion of the container from below and sealing the lower end portion of the opening with a seal member, and the seal member is constituted by a protection device. Electric compressor.