JPS62228680A - Compression capacity variable mechanism in swash plate type compressor - Google Patents

Abstract

PURPOSE:To allow a continuous change of the compression capacity in response to a change of the cooling load by inserting or withdrawing an adjusting body into or from a compression chamber by the pressure difference generated between the swash plate chamber pressure and the compression chamber pressure during an intake stroke and changing the volume of the compression chamber. CONSTITUTION:When the cooling load is large, a solenoid value 26 on a passage 24 is closed, a solenoid valve 27 on a passage 25 is opened, and an intake chamber 17R is communicated to a swash plate chamber 4. As a result, the swash plate chamber 4 is kept at the same pressure as the intake chamber 17R, the pressure difference between the pressure of a pressure action chamber 9 communicated to the swash plate chamber 4 and the pressure of the compression chamber during an intake stroke is made zero, an adjusting body 19 is inserted into the pressure action chamber 9 by the energizing action of a spring 21, thus a 100%-operation condition is obtained in the compression chamber 7. Next, when the cooling load is lower than the preset value, a on the contrary, the adjusting body 19 is protruded into the compression chamber 7, thus its volume is decreased, and a small-capacity operation condition is obtained. Accordingly, the compression capacity can be continuously changed in response to a change of the cooling load.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a swash plate type compressor, and more specifically to a variable compression capacity compressor that is provided so that the compression capacity can be changed in response to changes in cooling load. swash plate type compressor.

[Conventional technology]

Conventionally, a method for changing the compression capacity of a swash plate compressor in response to changes in cooling load has been to create a pair of front and rear compression chambers facing each other on the front and rear sides with a swash plate chamber in between. A method of providing a load/unload switching mechanism in one of the compression chambers and switching from 100% operation to 50% operation via the switching mechanism;
More specifically, the suction valve or the discharge valve provided in some of the compression chambers on the front side or the rear side is provided so that it can move forward and backward, and when the cooling load decreases, the suction valve or the discharge valve is installed from the discharge port. A method has been proposed in which the compression capacity of the compressor as a whole is varied by disabling the compression action of the compression chambers by separating them.

[Problem that the invention seeks to solve]

However, in the method of changing the compression capacity through the load/unload switching mechanism as described above, it is possible to change the compression capacity in stages, such as switching from 100% operation to 50% operation. However, the problem is that the compression capacity cannot be changed steplessly in response to changes in the cooling load.

The present invention is an attempt to improve the above-mentioned problems, and its main feature is that the compression capacity can be changed steplessly in response to changes in the cooling load. There are problems that need to be solved.

That is, the compression capacity is changed by changing the suction volume of the compression chamber through a change in the differential pressure generated between the swash plate chamber pressure and the compression chamber pressure during the suction stroke. The specific means and effects are as follows.

[Means for solving problems]

■ A pressure acting chamber is provided between the head of the piston and the piston, and an adjusting body is provided so as to be freely retractable.

(2) A spring is interposed between the piston and the adjustment body to bias the adjustment body toward the pressure chamber.

(2) A pressure action chamber is provided in communication with the swash plate chamber, and the regulating body is provided so as to be moved into and out of the compression chamber by the differential pressure generated between the compression chamber pressure and the swash plate chamber (pressure action chamber) pressure during the suction stroke. That is, the volume of the compression chamber during inhalation is changed by moving the adjustment body into and out of the compression chamber.

[For production]

■ When the cooling load inside the vehicle is large The pressure in the swash plate chamber (pressure action chamber) is at the same pressure as the pressure in the compression chamber during the suction stroke (tri < suction pressure state), so the adjustment body is activated by the biasing action of the spring. A state in which it is immersed in the pressure action chamber, that is, a state in which it operates at a large capacity can be obtained.

■ When the cooling load in the vehicle interior is small The pressure in the swash plate chamber (pressure action chamber) is higher than the pressure in the compression chamber during the suction stroke, so the adjustment body overcomes the biasing action of the spring and increases the pressure in the compression chamber. A state in which the fuel cell is protruded toward the target, that is, a state in which the fuel is operated at a small capacity is obtained.

〔Example〕

Specific embodiments of the present invention will be described below with reference to illustrative drawings.

1 to 3 are drawings showing a first embodiment, and 1 indicates a cylinder block. The cylinder block 1 consists of a front cylinder block IF and a rear cylinder block IR.
A shaft hole 2' is provided in the center of the IR, and a drive shaft 2 is rotatably supported in the coaxial hole 2' via a bearing portion 16.16. One end of the drive shaft 2 passes through a front housing 15F (described later) and is connected to an electromagnetic clutch (not shown), and the driving force of the engine (not shown) is transmitted to the drive shaft through connection and disconnection of the electromagnetic clutch. It is provided so that it can be transmitted to 2. Further, an appropriate number of cylinder bores 3 are provided on the outer periphery of the shaft hole 2' so as to surround the coaxial hole 2'. Each cylinder bore 3 is divided into a front and rear pair with a suction passage 23 and an isolated swash plate chamber 4 in between. A compression chamber 7 is provided in which a double-headed piston 5 is fitted so as to be movable forward and backward. Each piston 5 has an opening at its tip end on the paddle side, forming a recess, and the recess has a pressure acting chamber 9 on the bottom side, into which a volume adjuster 19 is removably fitted. inserted. The pressure acting chamber 9 and the swash plate chamber 4 are provided so as to communicate with each other via a passage 20 formed in the piston 5. Further, a spring 21 is interposed in the pressure acting chamber 9 with both ends thereof engaging the opening of the recess and the bottom of the adjusting body 19.
is provided so as to be biased by the same spring 21 in the direction of sinking into the pressure acting chamber 9. On the other hand, a swash plate 6 is provided in the swash plate chamber 4 so as to be able to swing and rotate freely via the drive shaft 2, and the piston 5 is moored to the slope of the swash plate 6 via a shoe 8. It is provided so that the swinging rotation of the swash plate 6 can be transmitted to each piston 5 as a reciprocating motion.

15F is a front housing that covers the open end of the front cylinder block IF with the front valve plate 10F in between, and 15R is the rear valve plate 1.
This is a rear housing song that covers the open end of the rear cylinder block IR with 0R in between, and is a rain housing 15.
In F and 15R, suction chambers 17F and 17R and discharge chambers 18F and 18R are provided concentrically with an annular partition between them, corresponding to each of the cylinder bores 3. That is, the discharge chamber 1
8F and 18R are located in the center, and the suction chamber 17
F and 17R are provided near the outer periphery so as to surround the discharge chambers 18F and 18R.

Suction passages 23.23 are formed in the front cylinder block IF and rear cylinder block IR, and the suction chambers 17F, 17R and the swash plate chamber 4 are provided to communicate with each other via the suction passages 23.23. And front valve plate 10F and rear valve plate IOH
There are inlet ports 11 corresponding to the above-mentioned inlet chambers 17F and 17R.
F, 11R and discharge ports 12F, 12R are opened correspondingly to the discharge chambers 18F, 18R, respectively. Also, at the suction port 1.1F, IIR, there is a suction valve 1 located on the compression chamber 7 side.
3F and 13R are provided so as to be able to open and close freely through the suction stroke of the piston 5, and discharge ports 12F and 12R are located on the side of the discharge chambers 18F and 18R, and discharge valves 14F and 14R are provided so that they can be opened and closed during the suction stroke of the piston 5. It is provided so that it can be opened and closed freely through the opening.

The swash plate chamber 4 has passages 24 and 25 as pressure control means.
are provided so as to communicate with the discharge chamber 18F and the suction chamber 17R through the passages 24, 25, and electromagnetic valves 26, 27 are attached to both passages 24, 25, and the electromagnetic valves 26, 27 respond to changes in the cooling load. It is provided so that it can be selectively opened and closed by a control device 67. That is, when the cooling load in the vehicle interior is large, the solenoid valve 27 opens to send suction pressure to the swash plate chamber 4.

The other solenoid valve 26 is provided so that when the cooling load inside the vehicle is small, the other solenoid valve 26 is opened to send discharge pressure to the swash plate chamber 4.

However, in this embodiment, when the cooling load inside the vehicle is large, the passage 24 connecting the discharge chamber 18F and the swash plate chamber 4
The solenoid valve 26 interposed in the suction chamber 17R and the swash plate chamber 4 is closed, and the solenoid valve 27 interposed in the passage 25 connecting the suction chamber 17R and the swash plate chamber 4 is opened, that is, the suction chamber 17R and the swash plate chamber 4 are in communication, A state is obtained in which the swash plate chamber 4 is maintained at the same pressure (suction pressure) as the suction chamber 17R. In this manner, in a state where the swash plate chamber 4 is maintained at the same pressure (suction pressure) as the suction chamber 17R, the pressure action chamber 9 communicating with the swash plate chamber 4 in each cylinder bore 3 is connected to the compression chamber 7 during the suction stroke.
, and the adjustment body 19 is retracted in the direction of the pressure action chamber 9 due to the biasing action of the spring 21, so that each compression chamber 7 has 100% volume and performs compression. In other words, an operating state of 100% operation is obtained.

By continuously achieving a 100% operating state in this way, the cooling load inside the vehicle gradually decreases, but when the cooling load falls below the set value, this is linked. Close the solenoid valve 27 that was in the state and open the other solenoid valve 26, that is, the discharge chamber 1
8F and the swash plate chamber 4 are brought into communication, and a state is obtained in which discharge pressure is sent to the swash plate chamber 4. As the discharge pressure is sent to the swash plate chamber 4 in this way, the pressure in the swash plate chamber 4 increases, and as the pressure in the swash plate chamber 4 increases in this way, it is transmitted to the pressure action chamber through the first passage 20. The pressure in the pressure chamber 9 will also rise, but when the pressure in the pressure action chamber 9 exceeds the pressure in the compression chamber 7 and the biasing pressure of the spring 21 during the suction stroke, the pressure difference will cause A state in which the adjustment body 19 pops out toward the compression chamber 7 is obtained. By the adjustment body 19 protruding toward the compression chamber 7 in this way, the volume within the compression chamber 7 during the suction stroke is reduced by that amount, thereby reducing the compression capacity.

That is, a small capacity operating state can be obtained.

In addition, when compression is performed with the regulator 19 protruding toward the compression chamber 7 during small-capacity operation as described above, as the piston 5 moves toward the top dead center, the inside of the compression chamber 7 increases. This will cause the pressure to increase,
In this manner, as the pressure within the compression chamber 7 increases, the differential pressure between the pressure application chamber 9 and the compression chamber 7 gradually decreases. In this way, as the differential pressure between the pressure chamber 9 and the compression chamber 7 decreases, the regulator 19 gradually moves backward into the pressure chamber 9, and when the piston 5 reaches the top dead center, the same The adjustment body 19 is completely immersed in the pressure acting chamber 9. Therefore, when the piston 5 reaches the top dead center, the regulator 19 will not hit the suction valves 13F and 13R.

4 and 5 are drawings showing the second embodiment,
Rear cylinder block IR and rear valve plate IQ
In R, there is a passage 28 communicating between the swash plate chamber 4 and the suction chamber 17R.
is drilled, while the same rear cylinder block IR, rear valve plate 10R1 and rear housing 1.5
A passage 29 is provided in R to communicate between the swash plate chamber 4 and the discharge chamber 18R.
a, 29b are bored and one-car passages 29a, 29b
A control valve 30 is provided between the two roads 29a through the control valve 30.

29b is provided so that it can be opened and closed.

That is, in the same control valve 30, both roads 29
A valve seat 31 is provided between a and 29b, and a suction pressure chamber 32 and an atmospheric pressure chamber 33 are disposed facing each other with a bellows 34 interposed therebetween. The suction pressure chamber 32 is connected to the suction chamber 17R via a passage 35.

The atmospheric pressure chambers 33 are provided so as to communicate with the atmosphere through passages 36, and a bellows 3 is provided in the atmospheric pressure chambers 33.
A spring 37 is interposed that biases 4 in the extension direction. Further, a valve rod 38 extends through the valve seat 31 on the bellows 34, and a ball valve 39 is provided at the tip of the valve rod 38 so as to be able to abut against the valve seat 31. That is, the ball valve 39 is provided so that a gap is created between the bellows 34 and the valve seat 31 (opened state) when the bellows 34 is extended.

However, in this embodiment, when the cooling load in the vehicle interior is large, the suction pressure is high, so the control valve 30 is in a closed state, that is, the pressure in the suction pressure chamber 32 is lower than that in the atmospheric pressure chamber 33. Set pressure (atmospheric pressure +
Since the bellows 34 is contracted by overcoming the biasing pressure of the spring 37, the valve seat 31 is closed by the ball valve 39. On the other hand, since the passage 28 is always in communication, the swash plate chamber 4 has the same pressure as the suction chamber 17R (
suction pressure). In this manner, when the swash plate chamber 4 is maintained at the same pressure (suction pressure) as the suction chamber 17R, the pressure action chamber 9 communicating with the swash plate chamber 4 in each cylinder bore 3 acts as the compression chamber 7 during the suction stroke. The pressure is the same, and the adjustment body 19 is retracted in the direction of the pressure action chamber 9 due to the biasing action of the spring, so that each compression chamber 7 is in a state in which compression is performed with 100% volume, that is, 100%. % operation status can be obtained.

By continuously achieving a 100% operating state like this, the suction pressure decreases as the cooling load inside the vehicle gradually decreases.
In the control valve 30, when the pressure in the suction pressure chamber 32 (suction pressure) is lower than the set pressure in the atmospheric pressure chamber 33 (atmospheric pressure + biasing pressure of the spring 37), the pressure difference causes the valve to contract until now. Bellows 34 in condition
is extended and presses the ball valve 39, that is, the passage 2
A state in which 9a and 29b are opened is obtained. When the passages 29a and 29b are opened in this way and the discharge pressure is sent into the swash plate chamber 4, the pressure inside the swash plate chamber 4 increases, and as the pressure inside the swash plate chamber 4 increases in this way, , the pressure in the pressure action chamber 9 will also rise via the passage 20, but the pressure in the pressure action chamber 9 will exceed the pressure in the compression chamber 7 and the biasing pressure of the spring 21 during the suction stroke. In the state where the pressure exceeds the limit, the pressure difference causes the regulating body 19
You can get a state of jumping out towards. As the adjustment body 19 protrudes toward the compression chamber 7 in this way, the volume inside the compression chamber 7 during the suction stroke is reduced by that amount, thereby reducing the compression capacity, that is, the small capacity operation state is reduced. can get.

FIG. 6 and FIG. 7 are drawings showing the third embodiment,
Rear cylinder block IR and rear valve plate 10
R1 and rear housing 15R have a swash plate chamber 4 and a suction chamber L.
Passages 40a and 40b are bored to communicate between 7R and both roads 140a.

A control valve 41 is provided between the passages 40a and 40b.
40b is provided so that it can be opened and closed. That is,
In the same control valve 41, one passage 40a, 4
A valve seat 42 is provided between the valve seat 42 and a suction pressure chamber 43 and an atmospheric pressure chamber 44, which are opposed to each other with a bellows 45 interposed therebetween.

The suction pressure chamber 43 is provided to communicate with the suction chamber 17R via the passage 40b, and the atmospheric pressure chamber 44 is provided to communicate with the atmosphere via the passage 46.
A spring 47 that biases the bellows 45 in the direction of extension is interposed therein. Further, a valve rod 48 extends through the valve seat 42 on the bellows 45, and a ball valve 49 is attached to the tip end of the valve rod 48.
is provided so that it can come into contact with the valve seat 42. That is, the ball valve 49 is in a state in which the bellows 45 is in contact with the valve seat 42 (closed state).
It is set up as shown in

However, in this embodiment, when the cooling load in the vehicle interior is large, the suction pressure is high, so the control valve 41 is in the open state, that is, the pressure in the suction pressure chamber 43 is at atmospheric pressure. Since the bellows 45 is in a contracted state by overcoming the pressure in the chamber 44 (atmospheric pressure + biasing pressure of the spring 47), a gap is created between the valve seat 42 and the ball valve 49. And like this, passages 40a, 4
Since 0b is in the open state, the swash plate chamber 4 is maintained at the same pressure (suction pressure) as the suction chamber 17R.

In this way, the swash plate chamber 4 has the same pressure as the suction chamber 17R (
When the pressure is maintained at the suction pressure (suction pressure), the pressure acting chamber 9 communicating with the swash plate chamber 4 in each cylinder bore 3 is at the same pressure as the compression chamber 7 during the suction stroke, and the adjustment body 19 is biased by the spring 21. By being recessed in the direction of the pressure action chamber 9, a state in which each compression chamber 7 has 100% volume and performs compression, that is, a 100% operating state is obtained.

By continuously achieving a 100% operating state like this, the suction pressure decreases as the cooling load inside the vehicle gradually decreases.
In this way, the suction pressure decreases, and the control valve 41
In the state where the pressure in the suction pressure chamber 43 (suction pressure) is lower than the set pressure in the atmospheric pressure chamber 44 (atmospheric pressure + biasing pressure of the spring 47), the pressure difference causes the pressure to contract until now. The state in which the bellows 45 expands due to the pressure difference and presses the ball valve 49, that is.

A state is obtained in which the passages 40a, 40b are closed. By closing the passages 40a and 40b in this way, the swash plate chamber 4 is in a sealed state.
In the sealed state, a part of the compressed gas in the compression chamber 7 leaks into the swash plate chamber 4 as blow-by gas from the gap formed between each cylinder bore 3 and the sliding surface of the piston 5. Due to this, the pressure inside the swash plate chamber 4 gradually increases. As the pressure in the swash plate chamber 4 rises in this way, the pressure in the pressure action chamber 9 also rises via the passage 20, and the pressure in the pressure action chamber 9 increases due to the suction. When the pressure in the compression chamber 7 during the stroke exceeds the biasing pressure of the spring 21, a state is obtained in which the adjustment body 19 pops out toward the compression chamber 7 due to the pressure difference. By the adjustment body 19 protruding toward the compression chamber 7 in this manner, the volume within the compression chamber 7 during the suction stroke is reduced by that amount, thereby reducing the compression capacity, that is, a small capacity operating state is obtained. .

FIG. 8 and FIG. 9 are drawings showing the fourth embodiment,
The suction flange 50 is formed into an L-shape, including a connecting passage 51a on the compressor side (after throttling part) and a connecting passage 51b on the suction pipe side (before throttling part), and a connecting passage 51b on the suction pipe side. A passage 52 that communicates with the swash plate chamber 4 is provided, and a suction throttle valve 53 is attached to the connecting portion of the surface connecting passages 51a and 51b, facing the connecting passage 51b on the suction pipe side, and controls the movement of the spool 54. It is provided so that the opening area of the connecting portion of the surface connecting passages 51a and 51b can be changed through the connecting portion. More specifically, a pressure chamber 55 (atmospheric pressure chamber 55) communicating with the atmosphere is provided at one end on the bottom side of the spool 54, and a spring 56 is interposed in the atmospheric pressure chamber 55. 54
A pressure chamber 58 is connected to one end of the head side via a bellows 57.
(Suction pressure chamber 58) is provided, and the suction pressure chamber 58 is provided so as to communicate with the connection passage 51b on the suction pipe side through a through hole 59 formed in the spool 54.

The spool 54 is provided so as to be able to move forward and backward through changes in the differential pressure generated between the atmospheric pressure chamber 55 and the suction pressure chamber 58. That is, the pressure inside the suction pressure chamber 58 (
When the suction pressure) exceeds the set pressure in the atmospheric pressure chamber 55 (atmospheric pressure + biasing pressure of the spring 56), the bellows 57 expands due to the pressure difference, and the spool 54 retreats toward the atmospheric pressure chamber 55. state, i.e. surface connection passage 51a,
51b has a large opening area and is in an open state, and the pressure in the suction pressure chamber 58 (suction pressure) is equal to the set pressure in the atmospheric pressure chamber 55 (the biasing of the atmospheric pressure spring 56). In a state where the pressure is lower than the above pressure, the bellows 57 contracts due to the pressure difference, and the spool 54 is pushed out in the direction of the connection passage 51b, that is, the connecting portion of the surface connection passages 51a and 51b has a small opening. It is provided so that an open state (apertured state) can be obtained.

However, in this embodiment, when the cooling load in the vehicle interior is large, the suction pressure is high, so that the pressure in the suction pressure chamber 58 in the suction throttle valve 53 is reduced to the set pressure in the atmospheric pressure chamber 55 (atmospheric pressure The state in which the bellows 57 is extended by overcoming the biasing pressure of the spring 56, that is, the spool 5
4 retreats to the atmospheric pressure chamber 55 side, and the surface connecting passages 51a, 5
By keeping the opening area of the connection part 1b wide open, the pressure in the connection passage 51b on the suction pipe side (pre-throttling pressure) and the pressure in the suction passage 60 (post-throttling pressure) are in the same pressure state. be. And the connection passage 51 on the suction pipe side
b communicates with the swash plate chamber 4 via the passage 52, and the suction passage 60 is the suction chamber 17F.

By being in communication with 17R, the swash plate chamber 4 is connected to the suction chamber 1.
The same pressure as 7F and 17R is obtained. In this way, the swash plate chamber 4 is the suction chamber 17F.

17R, the pressure acting chamber 9 communicating with the swash plate chamber 4 through the passage 20 is in the same pressure state as the compression chamber 7 during the suction stroke, and the adjusting body 19 is biased by the spring 21. A state of being immersed in the pressure action chamber 9 direction is obtained. Since the adjustment body 19 is in the retracted state in this manner, a state in which each compression chamber 7 has 100% capacity for compression, that is, a 100% operating state is obtained.

Since the operating state of 100% operation is continuously obtained in this way, the suction pressure decreases as the cooling load in the vehicle interior gradually decreases. In the suction throttle valve 53, when the pressure in the suction pressure chamber 58 (suction pressure) is lower than the set pressure in the atmospheric pressure chamber 55 (atmospheric pressure + biasing pressure of the spring 56), the pressure difference causes The bellows 57, which has been in an extended state, contracts and pushes out the spool 54 toward the connection passage 51b on the suction pipe side, that is, the effect of reducing the opening area at the joint between the two connection passages 51a and 51b (throttling effect). can get. In this way, by obtaining a throttling action at the connecting portion of the surface connecting passages 51a and 51b, both the connecting passages 51a
, 51b (pressure before throttling>pressure after throttling), and the suction chamber pressure decreases while the pressure inside the swash plate chamber 4 remains constant. As the suction chamber pressure decreases in this way, the pressure in the pressure action chamber 9 will rise relatively, but the pressure in the pressure action chamber 9 will be lower than the pressure in the compression chamber 7 during the suction stroke. When the pressure inside exceeds the biasing pressure of the spring 21, the pressure difference causes the adjustment body 19 to close the compression chamber 7.
You can get a state of jumping out towards. By the adjustment body 19 protruding toward the compression chamber 7 in this manner, the volume within the compression chamber 7 during the suction stroke is reduced by that amount, thereby reducing the compression capacity, that is, a small capacity operating state is obtained. .

FIG. 10 is a drawing showing a fifth embodiment, in which the swash plate chamber 4 is provided in direct communication with the suction passage 60 (portion in front of the throttle), and both valve plates 10F and IOR are provided with the suction passage 60. Openings 61F and 61R are provided to communicate between the suction chamber 17F and 17R, and the suction chamber 1
7F and 17R (rear aperture part) have the same openings 61F and 61.
Suction throttle valves 62F and 62R are attached facing R, and are provided so that the amount of throttle can be changed by moving the suction throttle valves 62F and 62R forward and backward through changes in suction pressure. More specifically, the suction throttle valve 62 has a pressure chamber 63 (atmospheric pressure chamber 63) communicating with the atmosphere.
), and the bellows 64 is provided to be expandable and retractable, and the atmospheric pressure chamber 63 is interposed with a spring 65 that biases the bellows 64 in the direction of extension, so that the suction pressure is adjusted to the set pressure ( When the pressure exceeds the biasing pressure of the atmospheric pressure spring 65, the bellows 64 contracts to form a large gap between the valve head 66, which is fixed to the tip of the bellows 64, and the opening 61. In addition, when the suction pressure is lower than the set pressure in the atmospheric pressure chamber 63 (atmospheric pressure + biasing pressure of the spring 65), the bellows 64 expands and the valve head 66 is fixed to the tip of the bellows 64. It is provided so that an effect of forming a small gap between the opening 61 and the opening 61 (squeezing effect) can be obtained.

However, in this embodiment, when the cooling load inside the vehicle is large, the suction pressure is high, so that the suction pressure at the suction throttle valve 62 is reduced to the pressure in the atmospheric pressure chamber 63 (atmospheric pressure → - the pressure applied by the spring 65). The state in which the bellows 64 is contracted by overcoming the pressure (pressure), that is, the valve head 66 is in the atmospheric pressure chamber 6
3 side and large m between opening 61 IfJI
Since I is in the formed state, the pressures in the swash plate chamber 4 and the suction chambers 17F and 17R are in the same pressure state. Since the swash plate chamber 4 is in the same pressure state as the suction chambers 17F and 17R in this way, the pressure chamber 9 communicating with the swash plate chamber 4 in each cylinder bore 3 is in the same pressure state as the compression chamber 7 during the suction stroke. , the adjustment body 1-9 is retracted in the direction of the pressure action chamber 9 due to the biasing action of the spring 21. Since the adjustment body 19 is in the retracted state in this manner, a state in which each compression chamber 7 has 100% capacity for compression, that is, a 100% operating state is obtained.

Since the operating state of 100% operation is continuously obtained in this way, the suction pressure decreases as the cooling load in the vehicle interior gradually decreases. Then, when the suction pressure in the suction throttle valve 62 is lower than the set pressure in the atmospheric pressure chamber 63 (atmospheric pressure + biasing pressure of the spring 65), the bellows 64, which has been in a contracted state until now, expands due to the pressure difference. This provides an effect of pushing out the valve head 66 toward the opening 61, that is, an effect of reducing the gap formed between the opening 61 and the valve head 66 (throttling effect). In this way, by obtaining a throttling action between the opening 61 and the valve head 66, the suction passage 60 (pre-throttling pressure) and the suction chamber 1
A pressure difference (pre-throttling pressure>post-throttling pressure) occurs between 7F and 17R (post-throttling pressure), and the suction chamber pressure decreases while the pressure in the swash plate chamber 4 communicating with the suction passage 60 remains constant. becomes.

As the suction chamber pressure decreases in this way, the pressure in the pressure action chamber 9 will rise relatively, but the pressure in the pressure action chamber 9 will be lower than the pressure in the compression chamber 7 during the suction stroke. When the pressure exceeds the biasing pressure of the spring 21, a state is obtained in which the adjustment body 19 pops out toward the compression chamber 7 due to the pressure difference.

By the adjustment body 19 protruding toward the compression chamber 7 in this manner, the volume within the compression chamber 7 during the suction stroke is reduced by that amount, thereby reducing the compression capacity, that is, a small capacity operating state is obtained. .

FIG. 11 is a drawing showing a sixth embodiment, and in each of the above embodiments, an adjustment body is attached to the inner diameter part of the piston 5.
In this embodiment, an adjustment body 19 is provided to be fitted into the outer diameter portion of the piston 5.

Although not shown, loading and unloading are provided in each of the above embodiments so that the compression capacity can be changed in one step by disabling the compression action on the front side or rear side. It is possible to combine mechanisms as appropriate. or.

In each of the above embodiments, the case is explained for a swash plate compressor with a fixed swash plate rocking angle, but it is also possible to implement it in a swash plate compressor with a variable swash plate rocking angle. be. Furthermore, it is also possible to provide the adjustment body only on either the front side or the rear side.

〔Effect of the invention〕

The present invention is constructed as described above, and as described above, the adjusting body is fitted into the head of the piston facing the compression chamber so as to be freely retractable, and the swash plate chamber is provided at the bottom of the adjusting body. A pressure acting chamber is provided in communication with the pressure acting chamber, and the regulator is moved in and out by the differential pressure generated between the pressure acting chamber (swash plate chamber) and the pressure in the compression chamber (suction chamber) during the suction stroke. That is, when the cooling load is large, the regulator is retracted into the piston to obtain 100% suction volume in the compression chamber, and when the cooling load is reduced,
By making it possible to reduce the suction volume of the compression chamber by protruding the adjustment body toward the compression chamber,
It has now become possible to change the compression capacity steplessly in response to changes in the cooling load.

[Brief explanation of drawings]

1 to 3 are drawings showing the first embodiment, in which FIG. 1 is a cross-sectional view showing the entire swash plate compressor (cross-sectional view taken along the line A-A in FIG. 2), and FIG. is an ipsilateral sectional view (first
FIG. 3 is a sectional view taken along line B-B in FIG. 2. 4 and 5 are drawings showing the second embodiment,
FIG. 4 is a sectional view showing the entire swash plate compressor, and FIG. 5 is a sectional view of the control valve portion. Figures 6 and 7
The drawings show a third embodiment, in which FIG. 6 is a sectional view showing the entire swash plate compressor, and FIG. 7 is a sectional view of the control valve portion. 8 and 9 are drawings showing a fourth embodiment, in which FIG. 8 is a sectional view showing the entire swash plate compressor, and FIG. 9 is a sectional view of the suction flange portion. FIG. 10 is a drawing showing the fifth embodiment, and is a sectional view showing the entire swash plate compressor. FIG. 11 is a drawing showing the sixth embodiment, and is a sectional view showing the entire swash plate compressor. 1...Cylinder block, IF...Front cylinder block, IR...Rear cylinder block,
2... Drive shaft, 2'... Shaft hole, 3... Cylinder bore, 4... Swash plate chamber, 5... Piston, 6... Swash plate, 7... Compression chamber, 8 ...Shoe, 9...Pressure action chamber, 1OF...Front valve plate, IOR・
...Rear valve plate, IIF, IIR...Intake port, 12F, 12R...Discharge port, 13F, 13R...
Suction valve, 14F, 14R...Discharge valve, 15F...Freon 1-housing, 15R...Rear housing, 1
6... Bearing part, 17F, 17R... Suction chamber, 18
F. 18R...Discharge chamber, 19...Adjusting body, 20...Passage, 21...Spring, 22...Tightening with bolt, 23
... Suction passage, 24.25... Passage, 26.27.
...Solenoid valve, 28...Passage, 29a, 29b-passage, 30...Control valve, 31...Valve seat, 3
2... Suction pressure chamber, 33... Atmospheric pressure chamber, 34...
・Bellows, 35.36...Passage, 37...Spring,
38...Valve rod, 39-...Ball valve, 40a, 40b
...Passage, 41...Control valve, 42...
・Valve seat, 43... Suction pressure chamber, 44... Atmospheric pressure chamber, 45... Bellows, 46... Passage, 47... Spring, 48... Valve rod, 49... Ball Valve, 50... Suction flange, 51a, 51b... Connection passage, 52...
・Passage, 53... Suction throttle valve, 54... Spool, 5
5... Atmospheric pressure chamber, 56... Spring, 57... Bellows, 58... Suction pressure chamber, 59... Through hole, 60...
-・Suction passage, 61 (61F, 61R)...opening, 62 (62F, 62R)...suction throttle valve, 63・
...Atmospheric pressure chamber, 64...Bellows. 65... Spring, 66... Valve head, 67... Control device.

Claims (1)

[Claims] (1) A pressure acting chamber is provided between the head of the piston, which is inserted into the cylinder bore so that it can move forward and backward through the rocking rotation of the swash plate, and the adjusting body is inserted into the head of the piston so that it can move in and out. A spring is interposed between the piston and the adjustment body so that it is always biased toward the pressure chamber,
The pressure acting chamber is a swash plate type, which is provided in communication with a swash plate chamber, and is provided so that the adjustment body is moved in and out of the compression chamber by the differential pressure generated between the pressure in the swash plate chamber and the pressure in the compression chamber during the suction stroke. Compression capacity variable mechanism in compressor.