JPH0248708Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention is a variable compression capacity swash plate compressor equipped with a loading/unloading switching mechanism, and more specifically, a swash plate compressor with a variable compression capacity equipped with a loading/unloading switching mechanism. A load/unload switching mechanism is provided in one of the pair of front and rear discharge chambers,
In a swash plate compressor, which is installed so that compression capacity corresponding to changes in cooling load can be obtained by switching one of the discharge chambers between load and unload, when switching from 100% operation to 50% operation, load is applied. The present invention relates to a mechanism for preventing uneven wear of a check valve provided to prevent compression pressure from flowing into the unloading side.

Prior Art In a swash plate compressor, one method of varying the compression capacity without disconnecting the electromagnetic clutch is to create a pair of front and rear discharge chambers facing each other on the front and rear sides with a swash plate chamber between them. Among these methods, a method has been proposed in which a loading/unloading switching mechanism is provided in one of the discharge chambers. FIG. 9 to FIG. 12 are drawings showing an example of this, and
A discharge valve 14R for opening and closing the discharge port 12R is provided in the rear side discharge chamber 18R so as to be able to move toward and away from the rear valve plate 10R, and the discharge valve 14R is separated from the rear valve plate when stopped and when the cooling load is low. In such a state, compression action cannot be obtained on the rear side, so the compressor as a whole can operate at 50%, and during high cooling loads, the pressure action chamber 25 has no discharge. By feeding pressure and pressing the discharge valve 14R against the rear valve plate 10R through the same discharge pressure, a compression action is also obtained on the rear side, so that 100% operation can be obtained.
In the swash plate compressor in which the rear discharge chamber 18R is equipped with a load/unload switching mechanism as described above, when the rear discharge chamber 18R is in the unloaded state, the air is discharged from the front discharge chamber 18F. Rear side discharge passage 2 is necessary to prevent refrigerant gas from flowing into the rear side (unload side).
A check valve mechanism is provided during 0R. More specifically, the check valve mechanism is composed of a housing 37 and a check valve 29, and the check valve 29, which is formed in a columnar shape and has a pair of upper and lower pressurized chambers 30a and 30b, can move forward and backward with respect to the housing 37. When inserted, one (lower) pressurizing chamber 30b communicates with the discharge chamber 18R at a surface corresponding to the bottom of the check valve 29, and the check valve 29
Discharge passage 20R on a surface corresponding to the outer peripheral part of
It is installed so that it communicates with the Further, the discharge passage 20R and the other (upper) pressurizing chamber 30a are provided with pressure guiding holes 34 extending in the radial direction of the check valve 29.
They are provided so as to communicate with each other via a pressure guiding hole 35 which is cut in the center and extends in the direction of the center line. And the rear side is loaded (100% operating state)
When the check valve 29 is pushed up through the discharge pressure of the refrigerant gas compressed on the rear side, that is, the open state is obtained, and when the rear side is in the unloaded state (50% operating state) A part of the refrigerant gas compressed on the front side passes through the discharge passage 20R and the pressure guiding holes 34 and 35 to the upper pressurizing chamber 3.
0a, and the check valve 29 is opened by the inflow pressure.
It is provided so as to obtain a state of pressing down, that is, a state of blocking the discharge passage 20R.

Problems to be solved by the invention However, in the case of the check valve mechanism as described above, when the rear side is in an unloaded state and the check valve 29 blocks the discharge passage 20R, the front side discharge passage 20F The discharge pressure of the refrigerant gas flowing into the discharge passage 20R on the rear side is controlled by the check valve 29.
This side pressure causes the check valve 29 to move at an angle of 180 degrees with respect to the opening of the discharge passage 20R.
The side that is displaced is pressed against the inner wall surface of the housing 37, and its free rotation is restricted. There is a problem in that uneven wear occurs in the check valve 29 as the check valve 29 moves back and forth within the housing 37 in a state in which the side displaced by 180 degrees is pressed against the inner wall surface of the housing 37.

In addition, due to uneven wear on the check valve 29, the durability of the check valve 29 is significantly impaired, and in addition, smooth opening and closing of the check valve 29 cannot be achieved, and abrasion particles are generated. This results in problems such as poor sealing performance.

Means for Solving the Problems The present invention is an attempt to improve the conventional problems as described above. The purpose of the present invention is to prevent uneven wear of the check valve by providing a rotary blade portion so that rotational force can be applied to the check valve by discharge pressure. More specifically, a load/unload switching mechanism is provided in the discharge chamber on either the front side or the rear side of the check valve, and the tips of the discharge passages extending from both discharge chambers are merged within the discharge flange. A column-shaped check valve with a pair of pressurized chambers is provided on the side provided with the load/unload switching mechanism, and is movable forward and backward. A corresponding surface communicates with the discharge chamber, and a surface corresponding to the outer periphery of the check valve communicates with the discharge passage, while the check valve has an opening of the discharge passage and the other pressurizing chamber. In a swash plate compressor equipped with a load/unload switching mechanism formed by a pressure guiding hole that connects the The rotor blade portion is provided facing the opening of the pressure guiding hole, and when switching from the load state to the unload state, the rotor blade portion is sprayed with refrigerant gas flowing into the discharge passage. A portion of the check valve that comes into pressure contact with the inner wall surface of the housing on the side that is displaced 180 degrees with respect to the opening of the discharge passage by rotating the check valve with the discharge pressure of refrigerant gas. The purpose is to provide an effect of sliding in the direction of closing the discharge passage while shifting the discharge passage in the circumferential direction.

Embodiments Specific embodiments of the present invention will be described below with reference to illustrative drawings. 1 to 4 are drawings showing the first embodiment, and in each drawing, 1 indicates a cylinder block. The cylinder block 1 consists of a front cylinder block 1F and a rear cylinder block 1R.A shaft hole 2' is located in the center of both cylinder blocks 1F and 1R, and a bearing is provided in the coaxial hole 2'. Part 16,
The drive shaft 2 is rotatably supported via 16.
An electromagnetic clutch (not shown) is attached to one end of the drive shaft 2.
It is provided so that it can be connected and driven to an engine (not shown) through the connection and disconnection of the electromagnetic clutch. Further, an appropriate number of bores 3 are provided on the outer periphery of the shaft hole 2' so as to surround the coaxial hole 2'. Each bore 3 is divided into a front and rear pair with a swash plate chamber 4 in between, and a double-headed piston 5 is fitted into each bore 3. And the swash plate chamber 4
A swash plate 6 is provided to be swingable and rotatable via the drive shaft 2. The piston 5 is anchored to the slope of the swash plate 6 via a ball 7 and a shoe 8, and the rocking rotation of the swash plate 6 is transmitted to each piston 5 as a reciprocating motion. 15F is a front housing that covers the open end of the front cylinder block 1F with the front valve plate 10F in between, and 15R is the rear valve plate 1 as well.
This is a rear housing that covers the open end of the rear cylinder block 1R with 0R in between, and both housings 15F, 15R have suction chambers 17F, 17R and discharge chambers 18F, 1 corresponding to the respective bores 3.
8R are provided concentrically with an annular partition between them. That is, the discharge chambers 18F, 18R are located at the center, and the suction chambers 17F, 17R are located near the outer periphery so as to surround the discharge chambers 18F, 18R. The suction chambers 17F and 17R are provided so as to be able to communicate with the swash plate chamber 4. The front valve plate 10F and the rear valve plate 10R have suction ports 11F, 11R corresponding to the suction chambers 17F, 17R, and discharge chambers 18F, 11R.
Discharge ports 12F and 12R are opened correspondingly to 8R. Further, suction valves 13F and 13R are provided at the suction ports 11F and 11R so as to be located on the bore 3 side and can be opened and closed freely through the suction stroke of the piston 5, and discharge chambers 18F and 13R are provided at the discharge ports 12F and 12R.
Discharge valves 14F and 14R are provided on the 18R side so as to be openable and closable through the exhaust stroke of the piston 5.

And the rear valve plate 10R has a relief hole 2.
1 is provided. The relief hole 21 is provided in the rear valve plate 10R so that it can be covered by the discharge valve 14R.
It is located in the center of the city. Further, a spring seat 22 is provided in the rear cylinder block 1R in correspondence with the relief hole 21. The spring seat 22 is located at the center of the rear cylinder block 1R. A ventilation hole 22' is provided at the bottom of the relief hole 21.
is opened and provided so as to be able to communicate with the swash plate chamber 4 via the bearing portion 16 of the drive shaft 3 . On the other hand, the discharge chamber 18
A spool 24 is provided in R at a position facing the relief hole 21 and the spring seat 22 so as to be movable forward and backward. The back of the same spool 24 and the rear housing 1
A pressure action chamber 25 is provided between the inner wall surface of 5R and the pressure action chamber 25 can be selectively communicated with the discharge flange 20 and the suction flange through switching of a solenoid valve (not shown). provided as possible.

The solenoid valve is provided so as to obtain a switching action via a sensor mechanism (not shown) that detects changes in the cooling load in the vehicle interior, and a control mechanism that processes signals sent from the sensor mechanism. Also the same spool 2
A retainer 26 and a discharge valve 14R are fixed to the front surface of the valve 4 through screwing bolts 27. A spring 28 is interposed between the spool 24 and the spring seat 22, and the spool 24 is normally biased toward the pressure action chamber 25 by the spring 28. That is, as shown in FIG.
The discharge valve 14R is provided in such a manner that the discharge valve 14R does not come into close contact with the discharge port 12R, in other words, a gap is formed between the discharge port 12R and the discharge valve 14R.

From the front side discharge chamber 18F there is a discharge passage 20.
F extends, and a discharge passage 20R extends from the rear discharge chamber 18R, as will be described later, and one end of both discharge passages is provided so as to meet at the discharge flange 20. And the rear side discharge passage 20
R is provided with a check valve mechanism. The check valve mechanism is composed of a housing 37 and a check valve 29,
The housing 37 has a pair of upper and lower pressurizing chambers 30a and 30b at both ends thereof, into which the check valve 29 is fitted so as to be freely retractable. And both pressurizing chambers 30a, 30b
One of the pressurizing chambers, ie, the pressurizing chamber 30b located below, is provided so as to communicate with the discharge chamber 18R through a communication hole 31 at its bottom and with the discharge passage 20R at its side wall. A slight clearance 33 is formed between the lower end portion of the check valve 29, more specifically, the portion corresponding to the opening of the discharge passage 20R in the blocked state, and the inner wall surface of the pressurizing chamber 30b. A small diameter portion 29' is provided through the stepped portion, and a plurality of rotary blade portions 36 are provided at constant intervals in the circumferential direction in the small diameter portion 29'. More specifically, each rotor blade portion 36 has a long side 36a and a short side 36b, and is formed by cutting out a dogleg shape (wedge shape) along the circumferential direction.
The small diameter portion 29' has a plurality of pressure guiding holes 34...
is carved so as to extend in the radial direction with one opening facing each rotor blade section 36. Further, a pressure guiding hole 35 is carved in the center of the check valve 29 along its center line, and one end of the pressure guiding hole 35 communicates with each of the above-mentioned pressure guiding holes 34, and the other end It is provided so as to open toward the upper pressurizing chamber 30a.

5 and 6 are drawings showing a second embodiment, in which the rotor 36 has each pressure guiding hole 34... with respect to the center line along the radial direction of the check valve 29. In other words, each pressure guiding hole 34 is formed so as to extend along a tangential direction to the pressure guiding hole 35.

Further, FIGS. 7 and 8 are drawings showing a third embodiment, in which the rotor blade portion 36 is branched from the opening of each pressure guiding hole 34 and directed toward the bottom. It is formed by carving a spiral groove.

Next, its effect will be explained. In the first embodiment shown in FIGS. 1 to 4, FIG. 1 shows a state in which the compressor is not in operation, and the discharge valve 14R on the rear housing 15R side is in an open state. That is, the spool 24 is urged toward the pressure action chamber 25 by the spring 28, and a gap is formed between the rear valve plate 10R and the discharge valve 14R, in other words, the discharge port 12R and the relief hole 2.
1 are in an open state, and between the rear side discharge chamber 18R and the suction chamber there is a relief hole 21 and a spring seat 2.
2. They communicate with each other via the ventilation hole 22', the bearing part 16, and the swash plate chamber 4. Also, the check valve 29 descends toward the pressurizing chamber 30b due to its own weight and closes to the communication hole 3.
1 is closed, that is, the discharge passage 20R is closed by the check valve 29. As described above, the discharge port 12R and the relief hole 21 are opened on the rear housing 15R side, the rear discharge chamber 18R and the suction chamber communicate with each other, and the check valve 29 closes the discharge passage 20R. Drive shaft 2
A state in which the drive shaft 2 is rotated by transmitting the driving force of the engine to the drive shaft 2 through a connecting operation of an electromagnetic clutch (not shown) provided at one end, and a state in which the swash plate is rotated through the rotation of the drive shaft 2. 6 swings and rotates within the swash plate chamber 4, and each piston 5 continuously reciprocates within each bore 3.

On the other hand, refrigerant gas fed into the compressor via the evaporator and the suction pipe is fed from the suction flange through the swash plate chamber 4 into both the front and rear suction chambers. The refrigerant gas sent into the suction chamber 17F on the front housing 15F side forcibly pushes open the suction valve 13F through the negative pressure generated in the bore 3 during the suction stroke of each piston 5, and passes through the suction port 11F into the bore 3. At the same time, it is compressed through the exhaust stroke of each piston 5, and through the compression action, the discharge valve 14F is forcibly opened and sent into the discharge chamber 18F from the discharge port 12F, that is, the compression action is performed. However, the discharge port 12R is open to the refrigerant gas sent into the suction chamber on the rear housing 15R side, and the discharge chamber 18R has the escape hole 21 and the spring seat 2 as described above.
2. Since the piston 5 is in communication with the suction chamber via the bearing portion 16 and the swash plate chamber 4, no compression action is obtained even during the compression stroke of the piston 5. That is, at the start of operation, compression action is obtained only on the front housing 15F side (50% operating state).

The refrigerant gas compressed on the front side in this way is sent into the discharge pipe through the discharge passage, and a part of the refrigerant gas is sent into the pressure action chamber 25. This has the effect of increasing the internal pressure. Then, in a state where the pressure exceeds the pressure of the spring 28, the spool 2
4 overcomes the biasing pressure of the spring 28 and moves toward the rear valve plate 10R, and the second
As shown in the figure, the discharge valve 14R is in close contact with the rear valve plate 10R, and more specifically, the discharge valve 1
4R provides a state in which the discharge port 12R and the relief hole 21 are closed. Since the discharge port 12R and the relief hole 21 are thus closed by the discharge valve 14R, the refrigerant gas can be compressed on the rear housing 15R side as well.

Since the compression action is obtained on the rear side in this way, the gas compressed in the discharge chamber 18R side is sent into the pressurizing chamber 30b through the communication hole 31. By sending the compressed refrigerant gas into the pressure chamber 30b, the check valve 29 is pushed up by the discharge pressure of this refrigerant gas, and a state is obtained in which the discharge passage 20R is opened. In other words, 100% operating status can be obtained.

In this state where 100% operation is obtained, the cooling load in the passenger compartment decreases, and when the sensor mechanism detects the decrease in the cooling load, the solenoid valve is switched and the pressure acting chamber 25 The refrigerant gas (suction pressure) in the suction flange is sent to the suction flange, and as the suction pressure is sent to the pressure action chamber 25 in this way and the pressure in the pressure action chamber 25 decreases, , the biasing pressure of the spring 28 is overcome and the rear discharge valve 14R is opened.

In other words, the rear side is in an unloaded state and the discharge chamber 18
The pressure inside R drops rapidly. As the pressure on the rear side decreases in this way, the discharge pressure on the front side flows into the discharge passage 20R. This inflow pressure is then applied to the pressure guiding holes 34 and 3 from the pressurizing chamber 30b.
5 into the other pressurizing chamber 30a, and through the inflow pressure and the residual pressure in the pressurizing chamber 30a, an effect of pushing down the check valve 29, that is, an effect of closing the discharge passage 20R is obtained. The inflow pressure is blown onto the rotor blade section 36, and the discharge pressure has the effect of rotating the check valve 29.

Further, in the second embodiment shown in FIGS. 5 and 6, the inflow pressure is applied to the inside of the pressure guiding hole 34 (rotor blade portion 36) which is carved so as to extend along the tangential direction of the pressure guiding hole 35. In the third embodiment shown in FIGS. 7 and 8, the inflow pressure creates a spiral groove along the peripheral wall of the check valve 29. By being force-fed along the rotary blade portion 36 formed by this, the discharge pressure can rotate the check valve 29, as in the first embodiment.

Since the action of rotating the check valve 29 in each embodiment is obtained in this way, the check valve 29 is pressed against the inner wall surface of the housing on the side displaced by 180 degrees with respect to the opening of the discharge passage 20R. This provides an effect of opening and closing the check valve 29 while shifting its parts, that is, an effect of preventing uneven wear of the check valve 29.

Effects of the invention The invention is constructed as described above.
As mentioned above, the rotor blade portion is provided on the peripheral wall of the check valve in correspondence with the opening of the discharge passage, and the rotor blade portion is provided with a pressure guide hole provided in the check valve so as to communicate with one pressurizing chamber. It is provided facing the opening of the hole, and when switching from the loading state to the unloading state, the refrigerant gas that flows into the discharge passage on the unloading side is blown against the rotor blade, and the discharge pressure of the refrigerant gas causes the refrigerant to be reversed. By applying a rotational force to the stop valve, the check valve is discharged while slightly shifting the part that presses against the inner wall surface of the housing on the side that is displaced 180 degrees with respect to the opening of the discharge passage. It has now become possible to slide the check valve in the direction of closing the passage, and thereby it has become possible to effectively prevent uneven wear of the check valve.

By preventing uneven wear of the check valve in this way, the durability of the check valve can be improved, and the check valve can be opened and closed smoothly, and wear particles can be prevented. It has now become possible to prevent the deterioration of the sealing effect caused by this.

[Brief explanation of the drawing]

1 to 4 are drawings showing a first embodiment, in which FIG. 1 is a side sectional view showing the entire swash plate compressor according to the present invention, and FIG. 2 is a side view showing the same operating state. 3 is an enlarged view of the check valve mechanism portion, and FIG. 4 is a sectional view of the same check valve mechanism portion.
5 and 6 are drawings showing the second embodiment, in which FIG. 5 is an enlarged view of the check valve mechanism portion, and FIG. 6 is a sectional view thereof. 7 and 8 are drawings showing the third embodiment, in which FIG. 7 is an enlarged view of the check valve mechanism portion, and FIG. 8 is a sectional view thereof. 9 to 12 are drawings showing the conventional structure, in which FIG. 9 is a side sectional view showing the entire swash plate compressor, FIGS. 10 and 11 are enlarged views of the check valve mechanism part, FIG. 12 is a sectional view of the same. 1...Cylinder block, 1F...Front cylinder block, 1R...Rear cylinder block, 2...Drive shaft, 2'...Shaft hole, 3...Bore, 4...Swash plate chamber, 5...Piston, 6 ...Swash plate, 7...Ball, 8...Show, 10F...Front valve plate, 10R...Rear valve plate, 11F, 11R...Intake port, 12F, 1
2R...discharge port, 13F, 13R...suction valve, 1
4F, 14R...Discharge valve, 15F...Front housing, 15R...Rear housing, 16...
Bearing part, 17F, 17R...Suction chamber, 18F,
18R...Discharge chamber, 20...Discharge flange, 20
F, 20R...Discharge passage, 21...Relief hole, 22
...Spring seat, 22'...Vent hole, 24...Spool, 25...Pressure action chamber, 26...Retainer, 27...Bolt, 28...Spring, 29...Check valve, 29'... ...Small diameter portion, 30a, 30b...Pressure chamber, 31, 32...Communication hole, 33...Clearance, 34, 35...Pressure guiding hole, 36...Rotor blade portion, 36a...Long side, 36b... ...Short side, 37...
housing.

Claims (1)

[Scope of utility model registration request] A load/unload switching mechanism is provided in either the front or rear discharge chamber,
The distal ends of the discharge passages extending from both discharge chambers are arranged so as to meet within the discharge flange, and a check valve is formed in a columnar shape with a pair of pressurizing chambers on the side provided with the load/unload switching mechanism. One of the pressurizing chambers is provided so as to be movable forward and backward, and one of the pressurizing chambers is provided so as to communicate with the discharge chamber at a surface corresponding to the bottom of the check valve, and to communicate with the discharge passage at a surface corresponding to the outer periphery of the check valve. In a swash plate compressor equipped with a load/unload switching mechanism in which the check valve has a pressure guiding hole connecting the opening of the discharge passage and the other pressurizing chamber, the peripheral wall of the check valve is A rotor blade portion is formed in the portion so as to correspond to the opening portion of the discharge passage, and the rotor blade portion is provided facing the opening portion of the pressure guiding hole. Uneven wear prevention mechanism.