JP2003148335A - Fixed displacement swash plate type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixed displacement swash plate type compressor eliminating a shortage of lubricating oil in a crankcase upon starting. SOLUTION: A communicating passage is formed in a cylinder block for communicating a delivery chamber with the crankcase. An opening-closing valve with the damper function is arranged in the delivery chamber for closing a delivery chamber side end part of the communicating passage according to an increase in internal pressure of the delivery chamber, and opening a delivery chamber side outlet of the communicating passage according to reduction in the internal pressure of the delivery chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed capacity swash plate type compressor.

[0002]

2. Description of the Related Art Fixed capacity swash plate compressors are widely used in vehicle air conditioners and the like.

[0003]

When the fixed capacity swash plate type compressor is stopped, the refrigerant gas flows backward from the suction chamber to the crank chamber through the discharge passage for discharging the compressed leakage refrigerant gas from the crank chamber to the suction chamber, which causes a low temperature. May be liquefied in the crank chamber and become liquid refrigerant and may be accumulated in the crank chamber. When the fixed capacity swash plate type compressor is started with the liquid refrigerant accumulated in the crank chamber, the lubricating oil adhering to the swash plate and piston is washed out by the liquid refrigerant accumulated in the crank chamber and discharged immediately after the start. It is discharged to the suction chamber through the passage. During operation of the compressor, lubricating oil is supplied to the crank chamber together with compressed leakage refrigerant gas. As a result, the sliding contact portion between the swash plate and the shoe and the sliding contact portion between the piston and the cylinder bore run short of lubricating oil for a predetermined time immediately after the start, and the sliding contact portion becomes a metal contact and is worn. The present invention has been made in view of the above problems,
An object of the present invention is to provide a fixed capacity swash plate compressor in which the lack of lubricating oil in the crank chamber at the time of starting is eliminated.

[0004]

In order to solve the above-mentioned problems, in the present invention, a communication passage for communicating the discharge chamber and the crank chamber is formed in the cylinder block, and the communication chamber is increased as the pressure in the discharge chamber increases. A fixed capacity swash plate type compressor is provided with an on-off valve with a damper function for closing the passage and opening the communication passage when the pressure in the discharge chamber decreases, provided in the discharge chamber. In the fixed capacity swash plate compressor according to the present invention, the pressure in the discharge chamber immediately rises when the compressor is started. The on-off valve closes the communication passage as the pressure in the discharge chamber rises, but a predetermined time elapses from the start of the compressor to the closing of the communication passage due to the damper function. During the passage of time, the refrigerant gas and the lubricating oil flow from the high pressure discharge chamber to the low pressure crank chamber. As a result, the lack of lubricating oil in the crank chamber at the time of starting is resolved.

In a preferred mode of the present invention, the on-off valve with a damper function returns a columnar valve body, a cylinder into which the columnar valve body is slidably inserted, and a columnar valve body to a retracted position housed in the cylinder body. A return spring is provided, and the opening / closing time of the on-off valve is adjusted by adjusting the minute annular gap between the cylindrical body and the columnar valve body. In a preferred aspect of the present invention, the on-off valve with a damper function includes a columnar valve body, a cylinder into which the columnar valve body is slidably inserted, and a return spring that returns the columnar valve body to a retracted position housed in the cylinder body. The opening / closing time of the on-off valve is adjusted by adjusting the hole diameter of the small-diameter through hole formed in the cylindrical body. An on-off valve with a damper function can be configured by a columnar valve body, a cylindrical body into which the columnar valve body is slidably inserted, and a return spring that returns the columnar valve body to a retracted position housed in the cylindrical body. The opening and closing time of the on-off valve is adjusted by adjusting the minute annular gap between the cylinder and the columnar valve, or by adjusting the hole diameter of the small diameter through hole formed in the cylinder, and the discharge chamber at the start of the compressor. It is possible to optimize the amount of lubricating oil supplied from the to the crank chamber.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A swash plate type compressor according to an embodiment of the present invention will be described. As shown in FIG. 1, a single-head fixed capacity swash plate compressor 100 includes a cylinder block 1 having a plurality of cylinder bores 1a and a center bore 1b, and a front portion that cooperates with the cylinder block 1 to form a crank chamber 3. And a housing 2. The cylinder head 4 cooperates with the cylinder block 1 so that the suction valve 5, the valve plate 6, and the discharge valve 7
Sandwiched between. A suction chamber 8 and a discharge chamber 9 are formed in the cylinder head 4. The suction chamber 8 communicates with the suction port, and the discharge chamber 9 communicates with the discharge port. The intake port and the discharge port are connected to a cooling circuit of a vehicle air conditioner (not shown).

The swash plate type compressor 100 further includes a drive shaft 10 extending in the crank chamber 3. One end of the drive shaft 10 penetrates the front housing 2 and extends to the outside of the front housing 2, and the other end thereof is the center bore 1 of the cylinder block.
It is fitted to the bearing attached to b.

A swash plate 11 arranged in the crank chamber 3 is fixed to the drive shaft 10. A pair of shoes 12 slidably abut on the peripheral edge of the swash plate 11 with the swash plate 11 interposed therebetween. A plurality of pairs of shoes 12 are arranged at intervals in the circumferential direction. Each pair of shoes 12 is held by a shoe holding portion formed at the tail portion of the single-headed piston 13. The head of the piston 13 is slidably inserted in the cylinder bore 1a.

Center bore 1b of cylinder block 1
Communicate with the suction chamber 8 via a refrigerant passage (not shown). Due to the center bore 1b and the refrigerant passage, the head of the piston 13 and the cylinder bore 1 during operation of the compressor 100.
A discharge passage is formed to discharge the compressed leakage refrigerant gas that has leaked into the crank chamber 3 through the sliding contact portion with a from the crank chamber 3 to the suction chamber 8.

A communication passage 14 is formed in the cylinder block 1 and the valve plate 6 to connect the crank chamber 3 and the discharge chamber 9 to each other. An on-off valve with a damper function 15 for opening and closing the end of the communication passage 14 on the discharge chamber 9 side is arranged in the discharge chamber 9.
As shown in FIG. 2, the on-off valve 15 with a damper function includes a columnar valve body 15a, a cylindrical body 15b into which the columnar valve body 15a is slidably inserted, a valve plate 6 and a columnar valve body 15a. It has a return spring 15c which is inserted and returns the columnar valve body 15a to the retracted position housed in the cylindrical body 15b shown in FIG. The columnar valve body 15a faces the end of the communication passage 14 on the discharge chamber 9 side with a slight gap.

In the swash plate compressor 100 according to the present invention, the drive shaft 10 is rotationally driven by an external drive source, the swash plate 11 rotates as the drive shaft 10 rotates, and the swash plate 11 passes through the shoes 12. As a result, the piston 13 is reciprocally driven.
Refrigerant gas that has recirculated from the cooling circuit of the vehicle air conditioner to the compressor 100 flows into the suction chamber 8 through the suction port and the valve plate 6
Is sucked into the cylinder bore 1a through the suction hole and the suction valve 5 formed in the cylinder, and is compressed and compressed by the piston 13.
It discharges into the discharge chamber 9 through the discharge hole formed in the valve plate 6 and the discharge valve 7, and returns to the cooling circuit of the vehicle air conditioner through the discharge port.

When the swash plate type compressor 100 is started, the internal pressure of the discharge chamber 9 immediately rises. 2 by the return spring 15c
The columnar valve body 15a that has returned to the retracted position shown in (a)
However, due to the pressure difference between the internal pressure of the discharge chamber 9 and the internal pressure of the crank chamber 3, it is sucked and slides in the direction of the communication passage 14. Columnar valve body 15
In the low pressure space formed in the cylindrical body 15b by sliding a,
As shown by the arrow in FIG. 2B, the high pressure gas in the discharge chamber 9 flows at a low speed through the minute annular gap between the columnar valve body 15a and the cylindrical body 15b. Since the inflow speed of the high pressure gas into the low pressure space is low, the sliding speed of the columnar valve body 15a is suppressed. As a result, the columnar valve element 15a slides from the retracted position shown in FIG. 2 (a) to the operating position shown in FIG. 2 (b), and a predetermined period is taken until the end of the communication passage 14 on the discharge chamber 9 side is closed. Time passes. During the passage of time, as shown by the arrow in FIG. 2A, the refrigerant gas and the lubricating oil flow from the high pressure discharge chamber 9 into the low pressure crank chamber 3. As a result, the lack of lubricating oil in the crank chamber 3 at the time of starting the compressor is resolved. During operation of the swash plate compressor 100, compressed leak refrigerant gas and lubricating oil leak to the crank chamber 3 through the gap between the head of the piston 13 and the cylinder bore 1a, so that the crank chamber 3 is not lubricated. There is no shortage. Columnar valve body 15a and cylindrical body 15
2 (a) and 2 (b) by adjusting the minute annular gap between the b and b to adjust the inflow velocity of the high-pressure gas into the low-pressure space formed in the cylindrical body 15b. It is possible to optimize the amount of lubricating oil supplied from the discharge chamber 9 to the crank chamber 3 at the time of starting the swash plate compressor 100 by adjusting the transition time between and, that is, the opening / closing time of the damper function opening / closing valve 15. it can.

As shown in FIG. 3, a small diameter through hole 15d may be formed in the cylindrical body 15b. The high pressure gas in the discharge chamber 9
The small-diameter through hole 15 is provided in the low-pressure space formed in the cylindrical body 15b.
The damper function is exerted by flowing at a low speed through d. By adjusting the diameter of the small-diameter through hole 15d, the opening / closing time of the opening / closing valve 15 with a damper function is adjusted, and when the swash plate compressor 100 is started, the discharge chamber 9 to the crank chamber 3 are started.
The amount of lubricating oil supplied to the can be optimized.

As shown in FIG. 4, a bottomed tubular locking member 1 is provided.
5e is press-fitted and fixed to the cylindrical body 15b, a recess is formed at one end of the columnar valve body 15a, and the cylindrical portion of the locking member 15e and the columnar valve body 15 are formed.
The columnar valve body 15a and the locking member 15e may be connected by using a return spring 15f that can be housed in the recess of a. When the swash plate compressor 100 is started, the internal pressure of the discharge chamber 9 immediately rises. The columnar valve body 15a, which has been returned to the retracted position shown in FIG. 4A by the return spring 15f, is attracted and slides toward the communication passage 14 due to the differential pressure between the internal pressure of the discharge chamber 9 and the internal pressure of the crank chamber 3. The cylindrical body 15b is formed by sliding the columnar valve body 15a.
In the low-pressure space formed inside, as shown by the arrow in FIG. 4 (b), the high-pressure gas in the discharge chamber 9 flows at a low speed through the minute annular gap between the columnar valve body 15a and the cylindrical body 15b. Inflow.
Since the inflow speed of the high pressure gas into the low pressure space is low, the sliding speed of the columnar valve body 15a is suppressed. As a result, the columnar valve body 15a slides from the retracted position shown in FIG. 4 (a) to the operating position shown in FIG. 4 (b), and a predetermined period is reached before the end of the communication passage 14 on the discharge chamber 9 side is closed. Time passes. During the passage of the time, as shown by the arrow in FIG. 4A, the refrigerant gas and the lubricating oil flow from the high pressure discharge chamber 9 into the low pressure crank chamber 3. As a result, the crank chamber 3 when starting the compressor
The lack of lubricating oil is solved. Columnar valve body 15a and cylindrical body 15
4 (a) and 4 (b) by adjusting the minute annular gap between the b and b to adjust the inflow velocity of the high-pressure gas into the low-pressure space formed in the cylindrical body 15b. It is possible to optimize the amount of lubricating oil supplied from the discharge chamber 9 to the crank chamber 3 at the time of starting the swash plate compressor 100 by adjusting the transition time between and, that is, the opening / closing time of the damper function opening / closing valve 15. it can.

As shown in FIG. 5, a small diameter through hole 15g may be formed in the cylindrical body 15b. The high pressure gas in the discharge chamber 9
The small-diameter through hole 15 is provided in the low-pressure space formed in the cylindrical body 15b.
The damper function is exerted by flowing at a low speed through g. By adjusting the diameter of the small-diameter through hole 15g, the opening / closing time of the damper function opening / closing valve 15 is adjusted, and when the swash plate type compressor 100 is started, the discharge chamber 9 to the crank chamber 3 are started.
The amount of lubricating oil supplied to the can be optimized.

The present invention is applicable to a single-head fixed capacity swash plate compressor and a double-head fixed capacity swash plate compressor.

[0017]

As described above, in the fixed capacity swash plate compressor according to the present invention, the discharge chamber pressure immediately rises when the compressor is started. The on-off valve closes the communication passage as the pressure in the discharge chamber rises, but a predetermined time elapses from the start of the compressor to the closing of the communication passage due to the damper function. During the passage of time, the refrigerant gas and the lubricating oil flow from the high pressure discharge chamber to the low pressure crank chamber. As a result, the lack of lubricating oil in the crank chamber at the time of starting is resolved.

[Brief description of drawings]

FIG. 1 is a structural diagram of a swash plate compressor according to an embodiment of the present invention. (A) is sectional drawing, (b) is bb of (a).
FIG.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a partially enlarged sectional view of a swash plate compressor according to another embodiment of the present invention.

FIG. 4 is a partially enlarged sectional view of a swash plate compressor according to another embodiment of the present invention.

FIG. 5 is a partially enlarged sectional view of a swash plate compressor according to another embodiment of the present invention.

[Explanation of symbols]

1 cylinder block 1a Cylinder bore 1b Center bore 2 Front housing 3 crank chambers 4 cylinder head 8 Inhalation chamber 9 Discharge chamber 11 swash plate 12 shoe 13 pistons 14 passages 15 on-off valve

Claims (3)

[Claims] 1. A communication passage is formed in a cylinder block for communicating a discharge chamber and a crank chamber, the communication passage is closed as the pressure in the discharge chamber rises, and the communication passage is opened as the pressure in the discharge chamber decreases. A fixed capacity swash plate compressor characterized in that an on-off valve with a damper function is disposed in the discharge chamber. 2. An on-off valve with a damper function has a columnar valve body, a cylindrical body into which the columnar valve body is slidably inserted, and a return spring for returning the columnar valve body to a retracted position housed in the cylindrical body. The fixed capacity swash plate compressor according to claim 1, wherein the opening / closing time of the on-off valve is adjusted by adjusting a minute annular gap between the cylindrical body and the columnar valve body. 3. An on-off valve having a damper function has a columnar valve body, a cylindrical body into which the columnar valve body is slidably inserted, and a return spring for returning the columnar valve body to a retracted position housed in the cylindrical body. The opening / closing time of the on-off valve is adjusted by adjusting the hole diameter of the small-diameter through hole formed in the cylindrical body.
The fixed capacity swash plate compressor described in.