JPS59229082A - Sliding vane compressor - Google Patents

Abstract

PURPOSE:To prevent scuffing from being caused between a rotor and a housing, by forming an external shape of the rotor in a tapered shape so that one side end face may be formed in a diameter smaller by a very little amount than the diameter of the other side end face. CONSTITUTION:A rotor 3 is formed in a tapered shape in which its external faces are formed with one side end face 3a in diameter smaller by a very little amount than the diameter of the other side end face 3b. An angle alpha of this taper is set to a very little angle because this angle, if it is set to a very large degree, worsens a seal of external surfaces of the rotor 3. Accordingly, a space between one end side of the rotor and an internal surface 8a of a housing larger than the space between the other end side of the rotor and the internal surface 8a of the housing is provided. In this way, the one end side of the rotor 3 is never forced to be attached to the internal surface 8a of the housing even if a vane groove 2 is forced to be opened by a liquid refrigerant.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vane compressor, and is particularly effective as a refrigerant compressor for use in automobile air conditioners.

In general, this type of compressor has a working chamber formed by the outer periphery of the rotor, the side surface of the vane, and the inner surface of the housing, and sucks in and compresses refrigerant and discharges refrigerant in response to changes in the volume of the working chamber. The vanes are then housed in vane grooves formed in the rotor. This vane groove was formed over the entire length of the side surface from the end surface of the rotor in order to particularly facilitate machining.

However, according to the experimental studies conducted by the present inventors, a problem was discovered in which the rotor stuck to the inner surface of the housing near the end surface on one end side of the rotor.

After conducting various studies on the cause of this problem, it was confirmed that it was due to the following reasons.

That is, in this type of compressor, liquid refrigerant may be present in the working chamber, especially at the time of startup, and if the compressor is started in this state, liquid compression will occur, causing the pressure in the working chamber to become abnormally high. Therefore, as shown in FIG. 1, an abnormally high pressure is applied to the side surface of the vane 1, and this pressure is applied to the side surface of the groove 2 so as to push the vane groove 2 open. The groove 2 is pushed open by this force, and in particular, since the groove 2 has a shape in which a hole is opened at the end face on one end side, the amount of pushing open at the end face on the one end side increases. Therefore, the outer surface of the rotor 3 is pressed against the inner surface of the housing 8 at this one end side end surface, causing galling between the rotor 3 and the housing 8.

The present invention was devised in view of the above-mentioned points, and an object of the present invention is to prevent galling between rotor housings and to enable stable operation of a compressor over a long period of time.

Therefore, the compressor of the present invention adopts a configuration in which the rotor has a cylindrical shape in which the end face on one end side has a slightly smaller diameter than the other end side.

Therefore, in the compressor of the present invention, even if the end face of one end of the rotor is pushed open due to sheet metal, liquid compression, etc., the outer surface of the rotor will not be pressed against the inner surface of the housing due to the pushing open. This prevents galling between the rotor and housing.

Next, an embodiment of the compressor of the present invention will be described based on the drawings.

First, the components of the compressor will be explained based on FIGS. 2 to 5. In the figure, 5 is the drive shaft, 3 is this shaft 5
The shaft 50-tor 3 is made of a ferrous metal material. A vane groove 2 is formed in the rotor 3 in a cross shape from an end surface 3a on one end thereof. A vane (2) is slidably disposed in the vane groove 2 and has a substantially U-shape, and the wall thickness of the central portion 1a is thinner than that of the vane main body portion 1b. The tip portion 1c of the vane 1 has a tapered shape that is somewhat thin. A rotor cover 6 covers one end surface of the rotor 3, and is connected to a screw hole formed in the rotor 3 via a bolt 7.

As shown by the broken line in FIG. 4, the rotor 3 has an outer surface tapered such that one end surface 3a has a slightly smaller diameter than the other end surface 3b. However, if the angle α of this taper becomes too large, the sealing of the outer surface of the rotor 3 will be poor, so the angle is extremely small. That is, while the rotor width is approximately 35 nm, the difference between the rotor diameter B on one end and the diameter A on the other end is approximately 0.005 fins.

Similarly, the vane cover 6 also has a tapered shape that becomes smaller in diameter toward the rotor one end side 3a.

This taper angle β is also extremely small, and when the cylindrical width M of the rotor cover 6 is about 10 mm, the diameter C on the rotor side is about 0.005 fi smaller than the diameter on the opposite side.

A housing 8 houses the rotor 3, and has a substantially cylindrical inner surface 8a. This housing inner surface 8a and the rotor 3
The outer surface and the vane 1 form a working chamber R. 9 is a discharge hole formed in the housing 8; 10 is a discharge valve that covers this discharge hole; 11 is a cover for this discharge valve 10;
．． The cover 11 is fixed to the housing 8 with screws 12.

Reference numeral 13 denotes a discharge chamber housing that covers the discharge valve 10 and is fixed to the housing 8 with bolts 15 via an elastic ring 14. 16 is an O-ring 17 on the side surface of one end of the housing 8.
This plate 1 is a side plate disposed through
6 has a discharge passage 18 communicating with the discharge chamber and a thrashing boat 19 opened at a position facing the working chamber R.

Further, a bearing 38 is driven into the plate 16, and the rotor cover 6 is rotatably supported by this bearing 38. Note that 22 is interposed between the discharge chamber housing 13 and the side plate 16 around the discharge passage 18,
This is an O-ring that performs sealing.

An oil separator 20 is disposed on the side plate 16 via a gasket 21, and communicates with the discharge chamber 13a via the discharge passage 18. A thrashing valve 23 is disposed within this oil separator, and this valve 23
The screw 26 is attached by the pulp presser 25 together with the spring 24.
and is fixed to the side plate 16. The thrashing valve 23 opens when the pressure inside the working chamber R becomes higher than the pressure inside the oil separator 20 by more than the set force of the spring 24, and prevents the inside of the working chamber R from becoming abnormally high pressure. Further, an oil supply passage 27 is formed in the valve holder 25, and this passage 27 communicates with the lower surface of the oil separator 20 via an oil supply pipe 28. Therefore, the lubricating oil accumulated in the lower part of the oil separator 20 is pushed up toward the oil supply passage 27 due to the pressure difference, and is supplied from the oil supply passage 27 to the one end surface 3a side of the rotor 3. Note that 29 is an oil filter and 30 is an oil check valve.

31 is connected to the oil separator 20 via an O-ring 32,
This is a discharge pipe attached with bolts 33. 3
4 is a blind plug that seals this pipe 31, and 49 is a pipe 31.
This is the discharge service valve installed in the. Discharge chamber 13
The refrigerant discharged from a to the oil separator 20 is discharged from the discharge pipe 31 after separating lubricating oil within the oil separator 20 .

A side plate 35 is attached to the other end of the housing via an O-ring 36, and a bearing 37 is driven into this plate 35.
supports the shaft 5 rotatably. Further, this plate 35 has a suction hole 56 that connects a suction chamber and a working chamber R, which will be described later.

39 is a front housing that is attached to the side plate 35 via a gasket 40, and has a suction chamber 41 inside.
and an oil storage chamber 42 (as shown in FIG. 2). 57 is a positioning pin for accurately attaching the gasket 40 to the side play 1/35.

A boss portion 43 is formed on the outer periphery of the front housing, and an electromagnetic clutch (not shown) is attached to this boss portion.

44 is a suction pipe attached to the front housing 39 via an O-ring 45 with a bolt 46, 47 is a suction service valve provided in the middle of this pipe 44, and 48 is a blind plug for sealing this pipe 44.

Reference numeral 50 denotes a shaft seal for sealing between the shaft 5 and the front housing 39, which includes a carbon ring 51 that rotates integrally with the shaft 5, and an O-ring 5 attached to the housing 39.
It consists of a fixing ring 53 fixed via 2. 54
is a key for fixing a hub portion of an electromagnetic clutch (not shown) to the tip of the shaft 5.

The above front housing 39 - gasket 40 - side plate 35 - housing 8 - side plate 16 - gasket 21 - oil separator 20 has through bolts 55
are integrally connected by.

Next, the operation of the compressor having the above configuration will be explained.

When an electromagnetic clutch (not shown) is engaged and the rotational force of the automobile engine is transmitted to the shaft 5, the shaft 5 is supported by bearings 37 and 38 and rotates within the housing 8. At a portion where the working chamber R expands in volume with this rotation, the refrigerant introduced into the suction chamber 41 from the evaporator of the refrigeration cycle is sucked into the working chamber R through the suction hole 56.

The sucked refrigerant is compressed as the volume of the working chamber R decreases,
The lubricating oil is discharged from the discharge hole 9 into the discharge chamber 13a, and after separating the lubricating oil in the oil separator 20, is discharged from the discharge pipe 31 to the condenser side of the refrigeration cycle.

If the refrigerant remains in a liquefied state in the working chamber, such as during startup, the pressure in the working chamber R will become abnormally high if it continues to rotate. However, in this example, since the thrashing valve 23 is provided, the abnormally high pressure within the working chamber R is released. Then, the liquid refrigerant that cannot escape from the thrashing valve 23 remains in the working chamber R, and as a result, the pressure in the working chamber R increases, and a load is generated on the rotor 3 that pushes open the vane groove 2 via the vane 1. Even in this case, the rotor 3 of this example does not bite into the inner surface 8a of the housing 8.

That is, as described above, the rotor of this example has a tapered shape in which the end surface 3a on one end side has a smaller diameter. A gap larger than the gap between the two is provided. Therefore, even if the vane groove 2 is pushed open by the vane 1, one end of the rotor 3 will not be pressed against the housing inner surface 8a.

Further, in the compressor of this embodiment, the lubricating oil accumulated in the lower part of the oil separator 20 is supplied to the end surface of the rotor cover 6 from the suction passage 27, and then the lubricating oil is guided from the outer surface of the rotor to the bearing 37 side due to the pressure difference. Therefore, sufficient suction is achieved between the bearings 37, 38, the rotor 3 and the housing 8, and the shaft seal.

Although the shaft seal 50 provides sufficient sealing,
Even if lubricating oil were to leak from the shaft seal 50, the leaked oil would be stopped by the oil stopper 58. and,
The stopped leaked oil is collected in the oil storage chamber 42 through a waste oil passage 59 formed in the front housing 39. Therefore,
In the compressor of this example, even if lubricating oil were to leak, the leaked oil would not scatter to the outside of the compressor, and the area around the compressor would not be contaminated by the leaked oil.

In the above-mentioned embodiment, the vane 1 penetrates the vane groove 2, and both ends 1c of the vane 1 are in contact with the inner surface of the housing 8a. However, if necessary, the vane 1 may be divided into two parts so that only one end of the vane 1 is in contact with the inner surface of the housing. 8a.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram schematically showing the vane groove of a conventional compressor, FIG. 2 is an exploded perspective view of an embodiment of the compressor of the present invention, and FIG. 3 is a front view of the rotor shown in FIG. FIG. 4 is a sectional view showing the assembled state of the compressor shown in FIG. 2. Figure 5 is a single part diagram of the vane. 1... Vane, 2... Vane groove, 3... Rotor,
5...Shaft, 6...Rotor cover, 8...Housing. Representative Patent Attorney Takashi Okabe 4.

Claims (1)

[Claims] A shaft that rotates in response to a driving force, a cylindrical rotor that rotates integrally with the shaft, a vane groove that is formed from one end surface of the rotor over the entire length of the side surface and that penetrates the rotor in a diametrical direction, and the vane groove. a rotor cover disposed on the end face of the rotor and covering the end of the vane groove; and a housing that accommodates the rotor and forms an operating chamber between the vane and the rotor outer circumferential vane. A vane type compressor, wherein the rotor has an outer shape that is tapered so that one end side has a slightly smaller diameter than the other end side.