JPS60216091A - Rotary compressor - Google Patents

Abstract

PURPOSE:To reduce driving load in time of starting as well as to make a rise in discharge pressure in time of high load operation checkable, by installing a spool valve which opens or closes a bypass port interconnecting a compression space and a suction chamber through, and moving this valve. CONSTITUTION:In time of starting of a compressor, since, no differential pressure is produced at both ends of a spool valve 101, this spool valve 101 is energized to the one end side by an energizin device, and a bypass port 100 is being opened. Therefore, the compressor comes to start after a compression space R passes through the bypass port 100 in consequence, whereby the driving force required for the compression comes to being smaller. During operation, when discharge pressure becomes abnormally high pressure, this high pressure is led into one end side of the spool valve 101 whereby the spool valve 101 further moves to the other end side. And, an interconnecting passage 104 whose one end is opened to a side wall of the spool valve 101 is interconnected to the bypass port 100 and thereby the compression space R is interconnected to the side of a suction chamber 10 via the interconnecting passage 104 so that volume is reduced and discharge pressure also drops to some extent, thus an abnormal rise is checkable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a rotary compressor, and is effective for use in, for example, an automobile air conditioner.

[Technical background]

Generally, a compressor for an automobile air conditioner rotates under the driving force of the automobile engine, so when the compressor is started, a starting load is applied to the engine, which causes discomfort to passengers.

Therefore, a compressor as shown in Japanese Patent Application No. 58-33185 has been proposed.

On the other hand, compressors for automobile air conditioners have a wide rotational speed range, and there is a problem in that the discharge pressure becomes extremely high at high rotational speeds or high loads.

In response to this, a compressor as shown in Japanese Patent Application No. 58-231771, for example, has been proposed.

However, these are intended for the starting load low range and the variable capacitance, respectively.

[Purpose of the invention]

Therefore, an object of the present invention is to obtain a rotary compressor that has both a starting load low range function and a variable capacity M function.

[Structure of the invention]

In order to achieve this objective, the present invention has the following configuration.

That is, a bypass port is provided to communicate the compression chamber and the suction chamber, and a spool valve is provided to open and close this bypass port. The discharge pressure discharged from the compression chamber is guided to one end of the spool valve, and the pressure inside the suction chamber is guided to the other end. Further, the spool valve has a communication passage, one end of which opens to a side wall of the spool valve, and the other end opens to the other end of the spool valve. When the compressor is started, there is no pressure difference between both ends of the spool valve, so the spool valve is biased toward one end by the biasing means, and the bypass port is opened.

During normal operation, discharge pressure is introduced to one end of the spool valve, and the spool valve moves to the other end, closing the bypass port. Therefore, the compressor operates at 100% capacity.

When the discharge pressure becomes abnormally high, this high pressure is introduced into one end of the spool valve, and the spool valve further moves. A communication passage whose one end opens in the side wall of the spool valve communicates with the bypass port, and the compression chamber communicates with the suction chamber via the communication passage, so that the capacity is reduced and the discharge pressure is also lowered.

〔Effect of the invention〕

By using the rotary compressor of the present invention, it is possible to reduce the driving load at startup, and also to suppress abnormal increases in discharge pressure during high rotation and high load.

〔Example〕

Next, examples of the present invention will be described. Figures 1 and 2
In the figure, reference numeral 1 denotes a shaft, which is rotated by receiving the driving force of a vehicle engine through an electromagnetic clutch (not shown). 2 is a cylindrical rotor that rotates integrally with this shaft. Vanes a3 are formed on the rotor 2 at four locations equally spaced apart in the circumferential direction. A vane 4 is slidably disposed within the vane groove 3. 5 is a front housing disposed on the front end surface of the rotor 2; 6 is a rear housing arranged on the rear side surface of the rotor 2;

7 is a compression chamber housing arranged so as to cover the rotor 2. A compression chamber R is formed by the inner surface of the compression chamber housing 7, the outer surface of the rotor 2, the vane 4, the front housing 5, and the rear housing 6. Further, the shaft 1 is rotatably supported by a front housing 5 and a rear housing 6 via bearings 8.

A suction chamber housing 9 is disposed on the front side of the front housing 5, and a suction chamber 10 is formed between the suction chamber housing 9 and the front housing 5. Reference numeral 11 denotes a suction passage provided in the suction chamber housing 9, which sucks refrigerant from an evaporator (not shown) of the refrigeration cycle. Reference numeral 12 denotes a shaft sealing device provided in the suction chamber housing to prevent the refrigerant inside the compressor from flowing out along the shaft 1.

A discharge chamber housing 13 is disposed on the rear side of the rear housing 6, and a discharge chamber 14 is formed between the discharge chamber housing 13 and the rear housing 6. A discharge hole (not shown) is formed in the rear housing 6 at a position where the capacity of the compression chamber R is minimized, and the refrigerant compressed in the compression chamber R passes through this discharge hole to the discharge chamber 14. is discharged.

Further, the discharge chamber housing 13 is formed with a discharge passage (not shown) for leading the refrigerant in the discharge chamber 14 to a not-shown condenser of the refrigeration cycle. 15 is an oil separator that separates oil in the refrigerant discharged into the discharge chamber 14.

The front housing 5 includes a compression chamber R and a suction chamber 1.
A bypass bow) 100 (diameter of about 6 to 7 cranes) is provided. Further, the front housing 5 is formed with a cylinder portion 17 that slidably supports a spool valve 101 made of brass that opens and closes the bypass port 100. That is, the spool valve 101 has a cylindrical shape with a diameter of about 9N and is disposed within the cylinder portion 17 without any gap, and the bypass port 100 is opened and closed by the reciprocating movement of the spool valve 101. 22 is the spool valve one end side 101a and the suction chamber 1 of this cylinder portion 17.
A communication hole 18 communicating with the spool valve 101 is a stopper provided at one end side 101a of the spool valve 101 within the cylinder portion 17.

Further, a flange portion 18b is formed at the rear end of the stopper 18, and a spring 19 is disposed between the flange portion 18b and one end side Iota of the spool valve to press the spool valve 101 toward the other end side 101b. ing. Further, a pressure guiding passage 20 is formed in the front housing 5 and the compression chamber housing 7 to guide the pressure in the discharge chamber 14 to the other end side 101b of the spool valve of the cylinder portion 17.

2 is a suction hole provided in the front housing 5, one end of which opens into the suction chamber IO, and the other end of which opens into the compression chamber R.
It is open to The refrigerant in the suction chamber 10 is sucked into the compression chamber R through this suction hole.

3 and 4 are a perspective view and a vertical sectional view of the spool valve 101. There is a communication passage 10 inside the spool valve 101.
4 is formed, and one end of this communication path 104 is connected to the spool valve 1.
A first opening 102 is opened in the side wall of the spool valve 101, and a second opening 10 is opened in the bottom surface of the llh end side 101b of the spool valve 101 at the other end.
It is open as 3. Although such a spool valve 101 is disposed within the cylinder portion 17,
The spool valve 101 is arranged so that the first opening 102 and the bypass port 100 face each other.

Next, the operation of this embodiment will be explained.

In the compressor, a rotor 2 rotates in response to a driving force from an automobile engine, and compresses and discharges refrigerant due to a change in volume of a compression chamber R accompanying this rotation. That is, the refrigerant is sucked into the suction passage 11.
, into the compression chamber R through the suction chamber 10 and the suction hole 25 formed in the front housing 5. The sucked refrigerant is compressed as the rotor 2 rotates, and then discharged into the discharge passage through the discharge hole and the discharge chamber 14.

By the way, when the compressor is stopped, no discharge pressure is generated in the discharge hole, so high pressure is not applied to the other end side 101b of the spool valve. Therefore, the spool valve 101
There is no pressure difference between the front and rear sides of the spool valve 101, and as shown in FIG.
is moving to. Therefore, as shown in FIG. 5, the spool valve 101 opens the bypass port 100.

Therefore, when the compressor starts rotating, the bypass port 100 is open, and the compressor starts compression after the compression chamber R passes through the bypass port 100, and the driving force required for the compression is It's small. Therefore, even when the compressor is started, a large shock is not given to the engine, and at the same time, no discomfort is caused to the passengers due to the start of the compressor.

A while after starting, high pressure is generated in the discharge hole, and this high pressure is applied to the other end 101b of the spool valve of the cylinder portion 17 via the pressure guiding passage 20.

When high pressure is applied to the other end side 101b in this way, a pressure difference is generated before and after the spool valve 101, and this pressure difference causes the spring 19
If the spool valve 101 overcomes the urging force, the spool valve 101 moves to the one end side 101a as shown in FIG.

Therefore, the bypass port loO is closed by the spool valve 101 and the compressor operates at 100% capacity.

During the above motion, the rotation of the compressor may increase and the discharge pressure may rise abnormally. In such a case, for example, if the pressure in the discharge chamber 14 rises to 25 kg/cIA or more, this increased pressure is transmitted to the spool valve 1 through the pressure guiding passage 20.
01 is applied to the other end side 101b, and the spool valve 101 further moves to the one end side 101a, changing from the state shown in FIG.
The state shown in the figure will be reached. Then, the first opening 102 provided in the side wall of the spool valve 101 communicates with the bypass port 100, and the bypass port 100. The compression chamber R and the suction chamber 10 communicate with each other via the first opening 102° and the communication passage 104.

Therefore, similarly to when starting compression, the compressor starts compression after the compression chamber R passes through the bypass port 100, and the compression capacity and discharge pressure decrease.

[Brief explanation of the drawing]

1 and 2 are a vertical cross-sectional view and a cross-sectional view showing an embodiment of the present invention, FIGS. 3 and 4 are a perspective view and a vertical cross-sectional view of a spool valve used in the embodiment device, and FIG. , FIG. 6, and FIG. 7 are sectional views showing the operation of the spool valve. l...shaft, 2...rotor, 4...vane,
5... Front housing, 6... Rear housing, 9... Suction chamber housing, 10... Suction chamber, 13
...Discharge chamber housing, 100... Bypass port, 101... Spool valve, 102... First opening, 1
03...Second opening, 104...Communication path. Representative Patent Attorney Takashi Okabe Figure 1 Figure 2

Claims (1)

[Claims] A shaft that rotates in response to an external driving force, a rotor that rotates integrally with the shaft, a vane that is slidably housed in the rotor, and a housing that houses the rotor and the vane to form a compression chamber. , a suction chamber provided in the housing for supplying working fluid to the compression chamber, a bypass port communicating the suction chamber and the compression chamber, and a discharge pressure discharged from the compression chamber being guided to one end side. , comprising a spool valve to which the pressure within the suction chamber is guided to the other end and which opens and closes the bypass port by sliding due to the pressure difference therebetween, and urging means for urging the spool valve toward the one end, A rotary compressor, wherein the spool valve is formed with a communication passage having a first opening that opens on a side wall of the spool valve and can communicate with the bypass port, and a second opening that opens on the other end side of the spool valve.