JPH01178785A - Electric compressor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a scroll type electric compressor.

Conventional technology FIG. 4 is a sectional view of a conventional scroll electric compressor.

In FIG. 4, a compression mechanism 42 is provided inside the airtight container 41.
A stator 44 of an electric motor 43 that drives the lightning is fixed, and a crankshaft 46 that drives the compression mechanism 42 is directly connected to the rotor 45 of the lightning @@43, and its rotating shaft is arranged almost horizontally. A lubricating oil reservoir 47 for storing lubricating oil is provided at the bottom.

The compression mechanism 42 includes a fixed spiral vane member 50 in which a fixed spiral vane 49 is integrally formed on a fixed frame 48, and a rotating spiral vane 51 that meshes with the fixed spiral vane 49 to form a plurality of compression work spaces 54. The rotating spiral blade 51 of the rotating mirror plate 52 has a rotating spiral blade member 53 formed on the end plate 52 and a rotation restraining member 56 that prevents the rotating spiral blade member 53 from rotating and only allows it to rotate. The crankshaft 4 is eccentrically driven by a swing drive bearing 55 provided on the opposite side.
a bearing member 61 having a main bearing 60 into which the eccentric shaft 57 of No. 6 is fitted and supporting a main shaft 59 formed on the crankshaft 46;
It is supported by

Refrigerant gas is supplied to the compression mechanism 4 via a compressor suction pipe 63 from a suction accumulator 62 provided separately from the closed container 41.
After being directly sucked into the suction port 64 of No. 2 and compressed, it is discharged from the discharge port 65 provided in the fixed frame 48 into the internal space of the closed container 41, passes near the electric motor 43, and is discharged into the discharge pipe 47 of the compressor. is discharged from the compressor.

The space on the opposite side of the rotating spiral blade 51 of the rotating mirror plate 52 forms a back pressure chamber 68, and the pressure in the back pressure chamber 68 is transferred to a back pressure hole 66 provided through the rotating mirror plate 52 at an appropriate position. With this pressure, the rotating head plate 52 lightly contacts the fixed frame 48 in the axial direction with its contact surface 69.

The lubricating oil in the lubricating oil reservoir 47 passes through the oil hole 72 provided in the main shaft 59 of the crankshaft 46 via the oil supply pipe 71, and then from the main shaft oil supply hole 73 to the main bearing gap 74 between the main shaft 59 and the main bearing 60.
It is led to the back pressure chamber 68 through the back pressure chamber 68. In addition, the lubricating oil that has entered the swing drive bearing 55 from the oil hole 72 enters the swing drive bearing gap 75.
Similarly, the back pressure chamber 68 is entered through the back pressure chamber 68. The lubricating oil in the back pressure chamber 68 flows into the compression work space from the contact surface 69 and the back pressure hole 66.

Problems to be Solved by the Invention As stated above, the back pressure chamber 68 is entered through the main bearing gap 74, the swing drive bearing gap 75, etc.? All of the IJ oil enters the compression work space 54. In this way, when a large amount of the lubricating oil that was on the high-temperature, high-pressure side enters the compression work space 54, the refrigerant gas on the suction side is superheated by the amount of heat, reducing the efficiency of the compressor.

Furthermore, since the flow rate of lubricating oil entering this compression work space 54 depends on the flow resistance of the lubricating oil in the main bearing gap 74 and the swing drive bearing gap 75, especially in the case of a compressor with variable rotation speed. During low-speed rotation, the amount of lubricating oil flowing into the compression work space 54 per rotation becomes excessive, and the efficiency of the compressor at this time decreases.

If the flow rate of this lubricating oil is adjusted to a low value, the power loss in these bearings may cause the temperature of the lubricating oil to rise excessively, causing damage to these bearings. Furthermore, if a rolling bearing that requires a relatively small flow rate of lubricating oil is used to solve this problem, problems such as increased bearing noise and increased costs will occur.

This back pressure also depends on the diameter of the back pressure hole 66, the main bearing gap 74,
Since it is determined depending on the flow resistance of the swing drive bearing gap 75, the state of gas inflow from this gap, the difference between the discharge pressure and the suction pressure, it is necessary to set the pressure to a high level with sufficient margin. The contact force of the flat surface becomes large, and there are problems of increased power loss due to sliding of the flat surface and increased amount of wear of the flat surface.

The present invention solves the above problems by making the contact force applied to the contact surface between the fixed frame and the rotating end plate a stable and appropriately small value, and reducing the amount of lubrication oil supplied to the bearing portion and the amount of oil flowing into the compression work space. It is an object of the present invention to provide an electric compressor in which an optimum value can be independently selected for the amount of lubricating oil.

Means for Solving the Problems In order to solve the problems of the above-mentioned conventional example, the present invention includes an electric motor inside a closed container, and a compressor that is driven by the electric motor and on which refrigerant pressure on the discharge side acts. The mechanism is arranged,
This compression mechanism includes a fixed spiral vane member formed with a fixed spiral vane on a fixed frame body, and a swirling spiral vane formed on a rotating head plate that engages with the fixed spiral vane to form a plurality of compression work spaces. A main bearing is provided with a main shaft formed at one end of a crankshaft that drives the turning spiral blade member eccentrically, and has a rotating spiral blade member and a rotation restraining member that prevents rotation of the rotating spiral blade member and allows only rotation. The peripheral plane of the fixed frame body and the peripheral plane of the swivel head plate are slidably abutted, and an axial restriction plate is provided on the back surface of the swivel head plate with a small gap therebetween. A back pressure partition band is provided to slidably seal and partition the gap so that compressor MDJ-υ) side pressure acts on the center side of the back side, and a pressure smaller than the discharge side pressure acts on the outside thereof. The discharge side pressure acts on the lubrication of the eccentric bearing part provided on the main shaft of the crankshaft and the main bearing part supporting the main shaft of the crankshaft so as to drive the turning spiral vane member in a turning manner. It is designed so that the parts of the water flow back and forth.

Effect: With the above configuration, the main bearing portion and the eccentric bearing portion are arranged in the part where the discharge side pressure on the center side of the back pressure partition band is applied.
By circulating the 71v11 clean oil in the space where the outlet pressure is applied to l, the optimum values can be independently selected for the amount of lubricating oil supplied to the bearing portion and the amount of lubricating oil flowing into the compression work space.

Furthermore, by appropriately selecting the inner area of the back pressure partition band, it is possible to stably bring the peripheral plane of the rotating mirror plate into contact with the peripheral plane of the fixed frame with an appropriate force.

Example An embodiment of the dual drive present invention will be described based on the drawings.

FIG. 1 is a longitudinal cross-sectional view of a scroll type electric compressor according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a compression mechanism portion of the electric compressor. In Figures 1 and 2, the closed container 1
Drive compressor @2 inside! II electricity! ! A stator 4 of the II machine 3 is fixed, and a crankshaft 6 for driving the compressor @2 is coupled to the rotor 5 of the electric motor 13, and the rotation axis of the crankshaft is arranged substantially horizontally. Further, the lower part of the closed container 1 is used as a lubricating oil reservoir 7.

The compression mechanism 2 includes a fixed spiral blade member 10 that has a fixed spiral blade 9 integrally formed on a fixed frame 8, and a rotating spiral blade 11 that meshes with the fixed spiral blade 9 to form a plurality of compression work spaces 14. The rotating spiral blade member 11 of the rotating mirror plate 12 has a rotating spiral blade member 13 formed on the end plate 12, and an autorotation restraining member 15 that prevents the rotating spiral blade member 13 from rotating and only allows it to rotate. The swing drive shaft 16 installed on the opposite side is connected to the main shaft 1 formed at one end of the crankshaft 6.
The crankshaft 6 is supported by a bearing member 21 having a main bearing 19 that supports the main shaft 7 . Further, as can be clearly seen from FIG. 3, an axial restriction plate 23 for restricting the axial movement of the rotating spiral blade member 13 is disposed from the back surface of the rotating mirror plate 12 with a minute gap 22 therebetween. 12
It is possible to freely slide between the back surface of the
An annular back pressure partition band 24 is disposed to seal and partition the back pressure chamber 25 so that discharge pressure acts on the center side of the back surface and a lower back pressure pressure acts on the back pressure chamber 25 on the outer periphery. The back pressure at the outer circumference is determined by minute holes, gaps, etc. communicating with the back pressure chamber 25.

The refrigerant gas sucked from the suction pipe 26 of the compressor enters the compression mechanism from the suction port 27 of the compression mechanism 2, and enters the compression work space 14.
It enters the rotor end cover 29 disposed at both ends of the stator 4 through the discharge port 28, passes through the motor side passage 31 from the rotor end cover opening 30, and enters the discharge pipe 33 from the discharge chamber 32. is discharged outside the compressor.

In this way, by arranging the main bearing part and the eccentric bearing part in the area where the discharge side pressure acts on the center side of the back pressure partition band, and by circulating the lubricating oil in the space where the discharge pressure acts, the compression Regardless of the amount of lubricant flowing into the work space, the amount of lubricant supplied to the bearing part can be sufficiently increased, and the back pressure is the discharge pressure acting on the inside of the partition plate, so by appropriately selecting the inner area, the rotating head plate The peripheral plane of the fixed frame can be brought into contact with the peripheral plane of the fixed frame with an appropriately small force.

Effects of the Invention As described above, according to the present invention, the amount of lubricating oil supplied to the bearing can be sufficiently increased regardless of the amount of lubricating oil flowing into the compression work space, resulting in high efficiency and high reliability over the entire rotational speed range. A sexual compressor is realized.

Further, since the contact force exerted on the contact surface between the swivel head plate and the fixed frame can be stably reduced to an appropriately small value, a compressor with high reliability and high efficiency can be obtained.

[Brief explanation of the drawing]

Figures 1 and 2 are longitudinal and cross-sectional views of an electric compressor according to an embodiment of the present invention, Figure 3 is a cross-sectional view of essential parts of the electric compressor, and Figure 4 is a conventional compressor. It is a longitudinal cross-sectional view of the electric compression (&. 1... Airtight container, 2... Compression mechanism, 3... Electric motor, 4... Motor stator, 5... Rotor, 6... Crankshaft, 7... Lubricating oil reservoir, 8... Fixed frame, 9.
・・Fixed spiral blade, 10 ・・Fixed spiral blade member, 11
...Swirling spiral vane, 12...Swivel mirror plate, 13...
Rotating spiral blade member, 14... Compression work space, 15...
・Rotation restraining member, 16... Rotating drive shaft, 17... Main shaft, 18... Eccentric bearing, 19... Main bearing, 27...
・Bearing part gap, 22... Micro gap, 23... Axial direction restriction plate, 24... Back pressure partition band, 25... Back pressure chamber, 26
...Suction pipe, 28...Discharge hole, 29...Rotor terminal cover, 30...Rotor end cover opening, 33...Discharge pipe. Agent Yoshihiro Morimoto

Claims (1)

[Claims] 1. An electric motor and a compression mechanism that is driven by the electric motor and applies discharge side pressure to the electric motor are disposed inside the airtight container, and the compression mechanism includes a fixed spiral vane formed on a fixed frame body. a swirling spiral vane member formed on a rotating head plate with a swirling spiral vane that engages with the fixed spiral vane to form a plurality of compression work spaces; and a swirling spiral vane member that prevents rotation of the swirling spiral vane member and only rotates. a rotation restraining part that allows the rotating spiral blade member to rotate eccentrically, and a main shaft formed at one end of a crankshaft that eccentrically drives the rotating spiral vane member is supported by a main bearing;
The peripheral plane of the fixed frame and the peripheral plane of the swivel head plate are slidably abutted, and an axial restriction plate is provided on the back surface of the swivel head plate with a small gap therebetween, and the center of the back surface of the swivel head plate is provided. A back pressure partition band is disposed to slidably seal and partition the gap so that the discharge side pressure of the compression mechanism acts on the side thereof, and a pressure smaller than the discharge side pressure acts on the outside thereof. The lubricating oil of the eccentric bearing part provided on the main shaft of the crankshaft and the main bearing part supporting the main shaft of the crankshaft so as to swing the blade member is circulated through the part on which the discharge side pressure acts. Electric compressor.