JP2000104684A - Variable displacement compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the variable displacement with a simple means by providing a communication passage for communicating a fluid suction side with a space for displacement of a value element to be forcibly vibrated with the exciting force generated with the rotation of a shaft through an elastic member. SOLUTION: In the case where this variable displacement compressor is applied for a scroll type compressor of refrigeration cycle for a vehicle, since a spool 23 is forcibly vibrated by the exciting force from a movable scroll 9 through a coil spring 25 with the rotation of the movable scroll, this vibration becomes the forced vibration of one degree of freedom system. Consequently, a bypass hole 22 can be opened and closed by a simple means for forcibly vibrating the spool 23 with the exciting force from the movable scroll 9 through a coil spring 25, while setting a natural frequency ω0 of a vibration system by the spool 23 and the coil spring 25 at a predetermined value. Variable characteristic of a compressor 100 can be stabilized while lowering the manufacturing cost and improving the reliability of the compressor 100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable displacement compressor, and is applicable to a compressor which needs to change a discharge capacity according to the number of rotations of a drive source for driving the compressor, such as a refrigeration cycle for a vehicle. It is effective.

[0002]

2. Description of the Related Art As a variable displacement type compressor, for example, in Japanese Patent Application Laid-Open Nos. 3-33486 and 58-101287, a bypass hole communicating with a fluid suction side is provided in an end plate portion of a fixed scroll. The capacity of the compressor is made variable by opening and closing the holes, and the opening and closing are performed using a solenoid valve or valve means that utilizes the differential pressure between the suction pressure and the discharge pressure.

[0003]

However, in the above-mentioned means, the number of parts constituting the variable displacement type compressor is increased and the structure is complicated. Therefore, the manufacturing cost and reliability of the variable displacement type compressor are increased. (Durability) is reduced. The present invention has been made in view of the above circumstances, and has as its object to provide a variable displacement type compressor that enables a variable displacement with simple means.

[0004] The present invention has been made in view of the above points, and has as its object.

[0005]

The present invention uses the following technical means to achieve the above object. According to the first aspect of the present invention, the bypass hole (22) for communicating the working chamber (V) with the fluid suction side is opened and closed, and the rotation of the shaft (4) is generated through the elastic member (25). And a communication path (27, 28) for communicating a space (24) where the valve element (23) vibrates and displaces with the fluid suction side. Features.

As a result, the valve element (23) is connected to the valve element (2).
Vibration (displacement) based on the natural frequency ω ₀ determined by the mass of 3) and the elastic constant of the elastic member (25).
Therefore, when the frequency ω of the orbiting scroll (9) is sufficiently smaller than the natural frequency ω ₀ , as described later, the valve element (23) has a phase and an amplitude substantially equal to those of the orbiting scroll (9). Vibrate. That is, if the bypass hole (22) is closed while the shaft (4) is stopped, the closed state is maintained, while the bypass hole (2) is maintained.
If 2) is open, the open state is maintained.

When the rotational frequency of the shaft (4) increases and the frequency ω becomes sufficiently larger than the natural frequency ω ₀ , the valve element (23) moves the movable scroll (9). That is, vibration (displacement) occurs with respect to the bypass hole (22), so that the bypass hole (22) can be opened and closed. Therefore, opening and closing of the bypass hole (22) can be performed by selecting an appropriate natural frequency ω ₀ .

A communication path (27, 2) for communicating a space (24) where the valve element (23) vibrates and displaces with the fluid suction side.
8), the lubricating oil flowing into the space (24) together with the fluid is discharged to the suction side. Therefore, the amount (state) of the lubricating oil existing between the valve body (23) and the space (24) can be maintained substantially constant, and a large change in the viscosity coefficient C can be suppressed. Thus, the variable characteristics of the variable displacement compressor can be stabilized.

As described above, according to the present invention, the natural frequency ω ₀ of the vibration system constituted by the valve element (23) and the elastic member (25) is set to a predetermined value, and the elastic member (25) is set. The bypass hole (22) can be opened and closed by simple means such as forcibly oscillating the valve element (23) via the valve, so that the manufacturing cost of the compressor can be reduced and the reliability (durability) can be improved. In addition, the variable characteristics of the variable displacement compressor can be stabilized.

According to the second aspect of the present invention, the bypass hole (22) for communicating the working chamber (V) with the fluid suction side.
And a valve element (23) that forcibly vibrates by receiving an exciting force generated by the rotation of the shaft (4) via an elastic member (25), and a valve element when the valve element (23) vibrates. A stopper (26) for mechanically regulating the maximum amplitude of the valve body (23) by colliding with the valve body (23);
3) a buffer portion (30) for reducing a collision force generated when the stopper (26) collides with the stopper (26).

Thus, the bypass hole (22) can be opened and closed by simple means as in the first aspect of the present invention, so that the manufacturing cost of the compressor and the reliability (durability) can be reduced. Improvement can be achieved. The buffer (3
0) is provided, so that the collision force can be absorbed by the buffer portion (30), so that the valve body (23) or the stopper (26) can be prevented from being damaged, and Noise and unnecessary vibration generated at the time of collision can be reduced.

According to the third aspect of the present invention, the working chamber (V)
A valve body (23) that opens and closes a bypass hole (22) that communicates with the fluid suction side, and that forcibly vibrates by receiving an exciting force generated by rotation of the shaft (4) via an elastic member (25). ) And a lid (26) for closing an end of the valve (23) in the vibration direction in a space (24) in which the valve (23) vibrates and displaces. (2
It is a non-linear elastic member located between the valve member (6) and the valve element (23), and whose elastic coefficient increases as the amount of deformation increases.

[0013] Thus, the bypass hole (22) can be opened and closed by simple means, similarly to the first aspect of the invention, so that the manufacturing cost of the compressor and the reliability (durability) can be reduced. Improvement can be achieved. In addition, the elastic member (2
In 5), since the elastic coefficient increases as the amount of deformation increases, the collision between the valve body (23) and the lid (26) can be suppressed. Assuming that the valve (23) and the lid (2)
6), the collision force can be reduced.

In the invention according to claim 4, the working chamber (V)
A valve body (23) that opens and closes a bypass hole (22) that communicates with the fluid suction side, and that forcibly vibrates by receiving an exciting force generated by rotation of the shaft (4) via an elastic member (25). ), A communication space (27, 28) for communicating between the vibration space (24) in which the valve element (23) vibrates and displaces and the spaces (24a, 24b) formed by the valve element (23) and the fluid suction side. A check valve (31) that allows fluid to flow only in one direction in the communication passages (27, 28).
And a space (24) according to the vibration displacement of the valve body (23).
a, 24b), the space (24
a, 24b) are characterized by constituting biasing means for applying a force corresponding to the vibration displacement of the valve element (23) to the valve element (23).

[0015] Thus, the bypass hole (22) can be opened and closed by simple means as in the first aspect of the present invention, so that the manufacturing cost of the compressor and the reliability (durability) can be reduced. Improvement can be achieved. In addition, space (24
a, 24b) and the communication path (2
7, 28) and a check valve (31) that allows the fluid to flow only in one direction in the communication path (27, 28). Of the variable displacement type compressor can be stabilized.

Here, the "elastic coefficient of the urging means" is a coefficient indicating the relationship between the amount of vibration displacement of the valve element (23) and the force applied to the valve element (23) in accordance with the vibration displacement. Is to say. According to the fifth aspect of the present invention, the valve body (23) displaceable with respect to the bypass hole (22) while opening and closing the bypass hole (22) for communicating the working chamber (V) with the fluid suction side. The valve body (23) has a valve body (23).
And a pressure receiving projection (23b) that is integrally displaced with the valve body (23), and is formed in such a manner that the pressure receiving projection (23b) slides and displaces. Space (32a) formed by 23b)
Transmits a force corresponding to the displacement of the valve element (23) to the pressure receiving projection (23).
b), and the valve element (23) receives a force from the urging means via the pressure receiving projection (23b) while rotating the shaft (4). It is characterized in that it is forcibly vibrated by receiving the generated exciting force.

[0017] Thus, the bypass hole (22) can be opened and closed by simple means as in the first aspect of the present invention, so that the manufacturing cost of the compressor and the reliability (durability) can be reduced. Improvement can be achieved. Further, by adjusting the size of the pressure receiving projection (23b), the elastic coefficient of the urging means can be easily changed, so that the variable characteristics can be easily adjusted.

In the invention according to claim 6, the working chamber (V)
A valve body (23) that opens and closes a bypass hole (22) that communicates with the fluid suction side, and that forcibly vibrates by receiving an exciting force generated by rotation of the shaft (4) via an elastic member (25). ), And the vibration space (24) in which the valve element (23) vibrates and displaces, and the spaces (24a, 24b) formed by the valve element (23) exert forces corresponding to the vibration displacement of the valve element (23). Is acted on the valve body (23) together with the elastic member (25).

Thus, the bypass hole (22) can be opened and closed by simple means as in the first aspect of the present invention, so that the manufacturing cost of the compressor and the reliability (durability) can be reduced. Improvement can be achieved. Incidentally, the reference numerals in parentheses of the above means are examples showing the correspondence with specific means described in the embodiments described later.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment)
The variable displacement compressor according to the present invention is applied to a scroll compressor (hereinafter abbreviated as a compressor) of a vehicle refrigeration cycle, and FIG. 1 shows a vehicle using a compressor 100 according to the present embodiment. It is a schematic diagram of a refrigeration cycle.

In FIG. 1, reference numeral 110 denotes a radiator (condenser) for cooling (condensing) the refrigerant discharged from the compressor 100.
A decompressor 120 decompresses the refrigerant flowing out of the radiator 110. Reference numeral 130 denotes an evaporator for evaporating the refrigerant in the gas-liquid two-phase state flowing out of the pressure reducer 120. The refrigerant flowing out of the evaporator 130 is sucked and compressed again by the compressor 100.

Next, the compressor 100 will be described. FIG.
Is a sectional view of the compressor 100. Reference numeral 1 denotes a front housing, 2 denotes a shell on which a fixed scroll described later is formed, 3 denotes a rear housing, and these 1 to 3 are fastened by bolts. Reference numeral 4 denotes a shaft which rotates in the front housing 1. The shaft 4 is usually connected to an external drive source (not shown) such as an engine or an electric motor via a driving force connecting / disconnecting means (not shown) such as an electromagnetic clutch. It rotates with the driving force from the motor. The shaft 4 is a bearing (radial bearing)
5 rotatably held by the front housing 1.

Reference numeral 7 denotes a crank portion integrally connected to the shaft 4 at a position eccentric from the center of rotation of the shaft 4 by a predetermined amount. The crank portion 7 has a shell-type (type having no inner ring) needle. Roller bearings (needle bearings)
A movable scroll (movable portion) 9 is rotatably connected to the movable scroll 9 via the movable member 8. As is well known, the orbiting scroll 9 includes a spiral tooth 9a and an end plate 9b integrally formed with the tooth 9a.
A so-called anti-rotation mechanism (not shown) for preventing the movable scroll 9 from rotating (rotating) around the crank portion 7 is provided on the end surface 1a and the end plate portion 9b of the front housing 1 facing the front housing 1. .

For this reason, the orbiting scroll 9 revolves (rotates) around the shaft 4 with the amount of eccentricity of the crank portion 7 as the revolving radius (rotating radius) without rotating along with the rotation of the shaft 4. By the way, 9c is a movable scroll 9
The balancer 9c is located on the opposite side of the center of gravity of the movable scroll 9 across the rotation center of the shaft 4 and rotates together with the shaft 4. is there.

The front housing 1 includes an evaporator 1
30 is formed with a suction port 13 connected to the refrigerant outflow side;
The shell 2 has a discharge port 14 connected to the refrigerant inflow side of the radiator 110, and the suction port 13 has a space formed by the front housing 1 and the shell 2 (hereinafter, this space is referred to as a suction chamber). .), And the shell 2 has a spiral tooth 2a that meshes with the tooth 9a of the orbiting scroll 9 to form the working chamber V, and an end plate integrally formed with the tooth 2a. A fixed scroll (fixed portion) 16 fixed to the front housing 1 is formed by the tooth portion 2a and the end plate portion 2b.

When the movable scroll 9 turns with respect to the fixed scroll 16 (shell 2), the working chamber V moves from the outer side of the spiral to the center of the spiral with the rotation of the movable scroll 9 as is well known. The volume is expanded to suck the refrigerant (compressible fluid) flowing into the suction chamber 15 from the suction port 13, and then the volume is reduced to compress the refrigerant while moving further toward the center of the spiral.

Reference numeral 17 denotes a discharge chamber from which the refrigerant compressed in the working chamber V is discharged. In the discharge chamber 17, the pressure pulsation of the discharged refrigerant is smoothed. And fixed scroll 1
At the center of the spiral in the end plate 2b of the shell 6 (shell 2), there is formed a discharge hole 18 that connects the discharge chamber 17 to the working chamber V whose internal pressure has increased to the discharge pressure (the volume has been reduced to the minimum). On the discharge chamber 17 side of the discharge hole 18,
A reed valve-shaped discharge valve 19 for preventing the refrigerant from flowing back from the discharge chamber 17 to the working chamber V is provided.

Reference numeral 20 denotes a valve stop plate (stopper) for regulating the maximum opening of the discharge valve 19, and the valve stop plate 20 is fixed to the end plate 2b together with the discharge valve 19 by bolts 21. By the way, as shown in FIGS. 2 to 5, the end plate portion 9b of the orbiting scroll 9 is formed with two bypass holes 22 for communicating the suction chamber 15 and the working chamber V. It is opened and closed by a spool valve body (hereinafter abbreviated as a spool) 23.

The spool 23 is slidably disposed in a guide hole 24 (vibration space) formed so as to extend in the radial direction of the end plate portion 9b. It is pressed so as to be sandwiched by two coil springs (elastic members) 25. Accordingly, the spool 23 is forcibly vibrated by receiving the exciting force from the movable scroll 9 via the coil spring 25 with the rotation of the movable scroll 9.

The natural length of the coil spring 25 is set so that when the movable scroll 9 is stopped, the spool 23 stops at the position where the bypass hole 22 is closed. A stopper 26 closes one end side (outside of the movable scroll 9) of the guide hole 24 and mechanically restricts the maximum amplitude of the spool 23 by colliding with the spool 23 when the spool 23 vibrates. (Lid).

A spool 23 is provided on each of the stopper 26 and the end plate 2b of the movable scroll 16 (shell 2).
Where the guide hole 24 and the suction chamber 1
5 (the refrigerant suction side), the first and second communication paths 27,
28 are formed. Further, the stopper 23 is provided on the spool 23 at the boundary of the spool 23 in the space of the guide hole 24.
Spring chamber 24 on the side (outside the diameter of movable scroll 9)
a and a spring chamber 24 on the radially inner side of the movable scroll 9.
The communication hole 23a which communicates with b is formed.

In FIG. 1, reference numeral 29 denotes a lip seal for preventing the refrigerant in the suction chamber 15 from leaking out of the compressor 100 (both housings 1 and 2) from the gap between the shaft 4 and the front housing 1. . Incidentally, the front housing 1, the shell 2, the rear housing 3 and the movable scroll 9 are made of aluminum, the spool 23 is made of titanium, tungsten or iron, and the stopper 26 is made of iron.

Next, the operation and features of the compressor 100 according to this embodiment will be described. The spool 23 is, as described above,
With the rotation of the orbiting scroll 9, the vibrating force is applied from the orbiting scroll 9 via the coil spring 25 to forcibly vibrate, so that the vibration becomes a one-degree-of-freedom system (due to displacement). Therefore, considering the viscous resistance when the spool 23 vibrates (displaces) in the guide hole 24, the amplitude ratio α
And the phase difference δ are, as is well known,
Becomes FIG. 6A is a graph showing Expression 1, and FIG. 6B is a graph showing Expression 2.

[0034]

Α = ｛(1−λ ² ) ² + (2 · γ · λ) ^{2 -1 −1} λ≡ω / ω ₀ ω: rotational frequency of the movable scroll 9 ω ₀ : due to the spool 23 and the coil spring 25 Natural frequency of vibration system ω ₀ = (2 k / m) ^1/2 k: spring constant (elastic constant) of coil spring 25 m: mass of spool 23 γ: viscous damping coefficient ratio (about 0.5 in this embodiment) (Γ = C / Cc) C: viscosity coefficient of the lubricating oil existing between the spool 23 and the guide hole 24 Cc: critical damping coefficient of the vibration system by the spool 23 and the coil spring 25 Cc = 2 · (2 km) ^1/2 The amplitude of the movable scroll 9 indicates a longitudinal component of the guide hole 24 in the displacement of the center of the movable scroll 9 (the center of the crank portion 7) with respect to the rotation center of the shaft 4 (revolution center of the movable scroll 9). , Spool 23
Of the spool 23 with respect to the rotation center of the shaft 4
4 shows the longitudinal component of the guide hole 24 in the displacement of the center (center of gravity) in the longitudinal direction.

[0035]

Δ = tan ⁻¹ {(2 · γ · λ) / (1−λ ² )} As is clear from the above formulas 1 and 2 and FIG. 6, the rotational speed of the movable scroll 9 (the excitation force Frequency) ω is spool 2
3 and a natural frequency ω _{0 of a} vibration system including the coil spring 25.
If it is smaller enough (λ << 1), the spool 23
Vibrates at a phase and an amplitude substantially equal to those of the movable scroll 9. That is, when the frequency ω is sufficiently smaller than the natural frequency ω ₀ , the spool 23 is substantially stopped with respect to the orbiting scroll 9, and the bypass hole 22 is closed.

On the other hand, when the rotational frequency of the movable scroll 9 increases and the frequency ω becomes sufficiently larger than the natural frequency ω ₀ (λ ≧ 1), the spool 23
Vibrates with a phase and an amplitude that are relatively large. In other words, when the frequency ω is sufficiently higher than the natural frequency ω ₀ , the spool 23 vibrates (displaces) with respect to the movable scroll 9, so that the spool 23 is It becomes impossible to stop at the position where the 23 is closed, and the bypass hole 22 is substantially opened.

Therefore, by selecting an appropriate natural frequency ω ₀ , the bypass hole 22 can be opened when the rotation speed of the orbiting scroll 9 exceeds a predetermined value, and the bypass hole 22 can be closed when the rotation speed is less than the predetermined value. . By the way, in a compressor for a refrigeration cycle, lubricating oil is mixed with refrigerant to lubricate the inside of the compressor 100, so that lubricating oil flowing into the guide hole 24 together with the refrigerant stays in the guide hole 24. , The viscosity coefficient C changes greatly, and the compressor 10
There is a possibility that the variable characteristic of 0 may change significantly.

Note that the "variable characteristic" here refers to a compression characteristic.
Speed of compressor 100 (shaft 4) and discharge of compressor 100
It refers to the relationship with the capacity, and specifically, the natural vibration
Number ω ₀Means that the discharge capacity increases or decreases at the boundary. Against this
Thus, in the present embodiment, both spring chambers 24a, 24b
The (guide hole 24) is connected to the suction chamber via the communication passages 27 and 28.
15 and both spring chambers 2 together with the refrigerant.
Lubricating oil flowing into 4a, 24b (guide hole 24) is sucked
It is discharged to the chamber 15 side. Therefore, the spool 23 and the
The amount (state) of the lubricating oil existing between the id holes 24 is substantially constant
Maintained, large changes in the viscosity coefficient C are suppressed.
Therefore, it is possible to stabilize the variable characteristics of the compressor 100.
it can.

As described above, according to the compressor 100 of the present embodiment, the spool 23 and the coil spring 25
The natural frequency ω ₀ of the vibration system is set to a predetermined value, and the opening and closing of the bypass hole 22 is performed by simple means such as forcibly vibrating the spool 23 by receiving an exciting force from the movable scroll 9 via the coil spring 25. As a result, the variable characteristics of the compressor 100 can be stabilized while reducing the manufacturing cost and improving the reliability (durability) of the compressor 100.

(Second Embodiment) In this embodiment, the frequency ω
Is sufficiently larger than the natural frequency ω ₀ (λ ≧ 1)
The spool 23 and the stopper 26 collide with each other,
7 or to prevent the stopper 26 from being damaged.
As shown in FIG. 8, a cushioning member 30 is provided to reduce a collision force generated when the spool 23 and the stopper 26 collide.

FIG. 7 shows an example in which a buffer member 30 made of an elastic material having a Young's modulus smaller than that of the spool 23 such as rubber or resin and the stopper 26 is disposed on the stopper 26 side. This is an example in which the buffer member 30 and the spool 23 are integrated with an adhesive. As a result, the collision force can be absorbed by the cushioning member 30, so that the spool 2
3 and the stopper 26 can be prevented from being damaged, and noise and unnecessary vibration generated when the spool 23 collides with the stopper 26 can be reduced.

(Third Embodiment) In the above-described embodiment, the coil spring 25 is a so-called linear coil spring that applies an elastic force to the spool 23 in proportion to the amount of deformation.
In this embodiment, as shown in FIGS. 9 and 10, the coil spring 25 is a non-linear coil spring (non-linear elastic member) whose elastic coefficient increases as the amount of deformation increases.

Thus, as in the first and second embodiments,
Compared to the case where the linear coil spring 25 is used, the spool 2
Since the elastic force of the coil spring 25 increases as the position 3 approaches the stopper 26, the collision between the spool 23 and the stopper 26 can be suppressed. Further, even if the spool 23 collides with the stopper 26, the collision force can be reduced.

FIG. 9 shows a non-linear spring characteristic using the coil spring 25 as a conical coil spring.
Is a diagram in which the spring characteristics are made non-linear by setting the coil springs 25 at unequal pitch. (Fourth Embodiment) In this embodiment, as shown in FIGS. 11 and 12, a communication hole is provided so that both spring chambers 24a and 24b become a closed space only when the volume of both spring chambers 24a and 24b is reduced. A check valve 31 that opens both communication passages 27 and 28 only when the refrigerant flows in a direction from the suction chamber 15 to the two spring chambers 24a and 24b is provided in each of the communication passages 27 and 28 while eliminating the 23a. is there.

The two check valves 31 are of the reed valve type, and each reed valve 31a is fixed to the end plate 9b and the stopper 26 by a screw 31b. Thus, the spring chambers 24a and 24b constitute spring means (biasing means) for applying a force to the spool 23 according to the vibration displacement of the spool 23 when the spool 23 vibrates to reduce its volume. Will be done.

Therefore, the average elastic constant k of the spring means acting on the spool 23 increases substantially in proportion to the pressure on the suction port 13 side (in the suction chamber 15), as shown in Expression 3, so that The higher the pressure on the 13th side, the higher the natural frequency ω ₀ determined by the spool 23 and the spring means.
Becomes larger.

[0047]

(Equation 3)

In calculating the natural frequency ω ₀ ,
The spring constant k of the coil spring 25 is sufficiently smaller than the elastic coefficient k of the spring means, and the spring constant k of the coil spring 25 is neglected to facilitate understanding of the present embodiment. FIG. 13 shows the pressure P _S in the suction chamber 15 (hereinafter referred to as the pressure P _S ).
Referred to as the suction pressure P _S. ) As a parameter, the mobile (a graph with the elastic coefficient k indicating the relationship between the displacement) distance x and the spring means, as is apparent from this graph, the suction pressure P _S
It can be seen that the elastic coefficient k of the spring means increases as the value of.

Next, the characteristic operation of this embodiment will be described.
As in the first embodiment, the rotational speed ω of the orbiting scroll 9
Is sufficiently smaller than the natural frequency ω ₀ determined by the spring means and the mass of the spool 23, the bypass hole 22 is closed. On the other hand, when the rotation speed ω is larger than the natural frequency ω _{0, the} open state and the closed state of the bypass hole 22 occur alternately, and the capacity sucked into the working chamber V is such that the bypass hole 22 is closed. From the time when the volume of the working chamber V starts to be reduced, and the capacity of the compressor 100 is reduced (variable).

By the way, both spring chambers 24a, 24b
When the volume of the two spring chambers 24a, 24b functions as spring means, the check valve 31 is closed when the volume of the two spring chambers 24a, 24b increases. Since it opens, the approximate suction pressure P
_The refrigerant having _S is led to both spring chambers 24a and 24b.

On the other hand, as is well known, when the heat load on the evaporator 130 increases, the suction pressure P _S rises in conjunction with the increase, so that the natural frequency ω ₀ also increases with the increase in the heat load on the evaporator 130. Then it gets bigger. Therefore, when the heat load increases and the refrigerating capacity is insufficient, the natural frequency ω ₀ increases, and the bypass hole 22 is closed even when the rotation speed ω of the orbiting scroll 9 increases (maximum capacity operation). Can be maintained. That is, when the refrigerating capacity is insufficient, the rotational speed ω of the orbiting scroll 9 (compressor 100)
Can be operated at maximum capacity with large
Insufficient refrigeration capacity can be eliminated promptly.

On the other hand, when the refrigerating capacity is excessive, the natural frequency ω ₀ decreases as the suction pressure P _S decreases, so that the variable displacement operation can be performed at a low rotational speed ω.
Therefore, when the refrigerating capacity is excessive, the operation is quickly switched from the maximum capacity operation to the variable capacity operation.
00 can be saved. By the way, even if the two communication passages 27 and 28 are closed (eliminated) and the two spring chambers 24a and 24b are closed, the two spring chambers 24a and 24b are closed.
24b can function as a spring means.

However, since the spool 23 is slidably displaced with a small gap from the guide hole 24, the spool 23 is reduced so that the volumes of the spring chambers 24a and 24b are reduced.
Is displaced, the refrigerant in the spring chambers 24a, 24b leaks out of the gap. On the other hand, when the spool 23 is displaced so as to increase the volume of the spring chambers 24a, 24b, the springs are displaced from the gap. The refrigerant in the chambers 24a and 24b flows in.

At this time, both spring chambers 24a, 24b
The amount of refrigerant that leaks when the volume of the spring chamber 24 is reduced does not always match the amount of refrigerant that flows when the volume of the spring chambers 24a and 24b increases.
The elastic coefficient k of the spring means when the volume of the spring chambers a and 24b is reduced does not match the elastic coefficient k of the spring means when the volume of the two spring chambers 24a and 24b is enlarged.
The variable characteristic of 00 becomes unstable.

On the other hand, in the present embodiment, only when the volume of both spring chambers 24a, 24b is reduced, both spring chambers 24a, 24b function as spring means.
When the volume of the two spring chambers 24a and 24b is increased, they do not function as spring means. Therefore, the variable characteristic of the compressor 100 is determined by the elastic coefficient k when the volume of the two spring chambers 24a and 24b is reduced. There is no influence of the elastic coefficient k when the volumes of the parts 24a and 24b are expanded. Therefore, the variable characteristics of the compressor 100 can be stabilized.

(Fifth Embodiment) In the fourth embodiment, the check valve 31 is provided so that the two spring chambers 24a, 24b are closed spaces only when the volume of the two spring chambers 24a, 24b is reduced. However, in the present embodiment, FIGS.
As shown in FIG. 7, the check valve 31 is provided so that the two spring chambers 24a and 24b become a closed space only when the volume of the two spring chambers 24a and 24b is increased.

Thus, in the present embodiment, the two spring chambers 24a and 24b function as spring means only when the volume of the two spring chambers 24a and 24b is increased, and when the volume of the two spring chambers 24a and 24b is reduced. Since it does not function as a spring means, the variable characteristics of the compressor 100 are determined by the elastic coefficient k when the volume of both spring chambers 24a and 24b is increased,
There is no influence of the elastic coefficient k when the volume of a, 24b is reduced. Therefore, the variable characteristics of the compressor 100 can be stabilized.

(Sixth Embodiment) In the fourth and fifth embodiments,
Although the check valves 31 are provided in the communication passages 27 and 28, in the present embodiment, as shown in FIGS. 16 and 17, the check valves 31 are eliminated to reduce the number of parts. By the way, the elastic coefficient k of the spring means changes according to the polytropic index κ, as is apparent from the above equation 3, and the polytropic index κ is determined by the hole diameter of the communication passages 27 and 28, that is, It can be adjusted by adjusting the spring chambers 24a, 24b.

In this embodiment, as in the fourth and fifth embodiments, the coil spring 2 has a smaller elastic modulus k than the spring means.
5, the spring constant k of the coil spring 25 is negligible. Incidentally, in the present embodiment, the hole diameters of the communication passages 27 and 28 are made smaller than in the fourth and fifth embodiments (κ ≒ 1.05), and the natural frequency ω ₀ is made smaller than in the fourth and fifth embodiments. I have.

(Seventh Embodiment) In the fourth to sixth embodiments,
Although the spring means is constituted by the two spring chambers 24a and 24b, in the present embodiment, as shown in FIGS. 18 and 19, the communication passages 27 and 28 are eliminated and the displacement of the spool 23 is made at both ends in the displacement direction of the spool 23. Pressure receiving projection 23b projecting in the direction
Is formed integrally with the spool 23, and the pressure receiving projection 2
3b and the pressure receiving protrusion 23b
A spring means (biasing means) for applying a force corresponding to the vibration displacement of the spool 23 to the pressure receiving protrusion 23b is constituted by the space 32a formed by the space 32a.

In the present embodiment, A in the above equation 3 indicates the area of the pressure receiving projection 23b in a cross section in a direction perpendicular to the direction in which the spool 23 moves, and A in the space 32a (displacement space 32). Equal to the cross-sectional area. In the present embodiment, as in the fourth to sixth embodiments, the spring constant k of the coil spring 25 is sufficiently smaller than the elastic coefficient k of the spring means, so that the spring constant k of the coil spring 25 can be ignored.

Accordingly, the spool 23 is forcibly vibrated by receiving the exciting force generated with the rotation of the shaft 4 while receiving the force from the spring means via the pressure receiving projection 23b. Incidentally, the elastic coefficient k of the spring means changes in proportion to the cross-sectional area of the space constituting the spring means, as is apparent from Equation (3). At this time, temporarily, the fourth to sixth
In the case where the force of the spring means is received by the cross-sectional area of the spool 23 as in the embodiment, it is necessary to reduce the cross-sectional area of the spool 23 in order to reduce the elastic coefficient k.

However, when the cross-sectional area of the spool 23 is reduced, the bypass hole 22 also needs to be correspondingly reduced, so that the discharge capacity of the compressor 100 may not be sufficiently changed (reduced). is there. On the other hand, in the present embodiment, since the force of the spring means is received by the pressure receiving projection 23b, by changing the sectional area of the pressure receiving projection 23b without changing the sectional area of the spool 23, Elastic modulus k, ie the natural frequency ω
₀ can be changed (adjusted).

(Eighth Embodiment) In the above embodiment, the movable scroll 9 is made of aluminum and the spool 23
Is made of titanium, tungsten, or iron, the thermal expansion coefficients of the two greatly differ, so that the gap between the spool 23 and the guide hole 24 changes with the temperature change of the compressor 100. For this reason, the slidability of the spool 23 changes with the temperature change (operating time) of the compressor 100, and accordingly, the variable characteristics may change.

Therefore, in the present embodiment, as shown in FIGS. 20 and 21, by disposing a cylindrical sleeve 33 between the spool 23 and the guide hole 24, the slidability is changed and the By adjusting the amount of lubricating oil existing between the guide holes 24, the viscosity coefficient C can be easily changed and adjusted. By the way, in the fourth to seventh embodiments, the natural frequency ω ₀ is examined only by the elastic coefficient k of the spring means, ignoring the elastic force of the coil spring 25, but the natural frequency ω ₀ is considered by considering both the coil spring 25 and the spring means. The compressor 100 may be configured by determining the frequency ω ₀ .

The compressor 100 according to the present invention can be used as another compressor such as an air pump or an air compressor for supercharging (turbocharger, supercharger, etc.). In the above-described embodiment, the coil spring 25 is used as the elastic member. However, a fluid spring such as an air spring, a bellows-shaped bellows, or other spring means may be used.

In the above-described embodiment, the spool 23 receives the exciting force from the movable scroll 9. However, the exciting crank portion that rotates together with the shaft 4 to apply the exciting force to the spool 23 is replaced with a movable scroll. 9 may be provided independently. In the above-described embodiment, one spool 2
Although one bypass hole 22 is opened and closed at 3, a plurality of bypass holes 22 may be opened and closed by one spool 23.

As is clear from the above description, the present invention forcibly vibrates the spool 23 using the centrifugal force generated with the rotation of the shaft 4 as the vibrating force to open and close the bypass hole 22. Since the present invention is performed, the application of the present invention is not limited to a scroll type compressor, but can be applied to other compressors such as a vane type and a rolling piston type.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a refrigeration cycle.

FIG. 2 is a sectional view of the compressor according to the first embodiment.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is an enlarged view of a portion B in FIG. 2;

FIG. 5 is an enlarged view of a portion C in FIG. 3;

6A is a graph showing a relationship between an amplitude ratio and a frequency ratio, and FIG. 6B is a graph showing a relationship between a phase difference and a frequency ratio.

FIG. 7 is an enlarged view of a portion corresponding to a portion B of the compressor according to the second embodiment.

FIG. 8 is an enlarged view of a portion corresponding to a portion B of the compressor according to the second embodiment.

FIG. 9 is an enlarged view of a portion corresponding to a portion B of the compressor according to the third embodiment.

FIG. 10 is an enlarged view of a portion corresponding to a portion B of the compressor according to the third embodiment.

FIG. 11 is an enlarged view of a portion corresponding to a portion B of a compressor according to a fourth embodiment.

FIG. 12 is an enlarged view of a portion corresponding to a portion B of a compressor according to a fourth embodiment.

FIG. 13 is a graph showing a relationship between a moving distance X and a coefficient of elasticity k using suction pressure as a parameter.

FIG. 14 is an enlarged view of a portion corresponding to a portion B of the compressor according to the fifth embodiment.

FIG. 15 is an enlarged view of a portion corresponding to a portion C of the compressor according to the fifth embodiment.

FIG. 16 is an enlarged view of a portion corresponding to a portion B of the compressor according to the sixth embodiment.

FIG. 17 is an enlarged view of a portion corresponding to a portion C of the compressor according to the sixth embodiment.

FIG. 18 is an enlarged view of a portion corresponding to a portion B of the compressor according to the seventh embodiment.

FIG. 19 is an enlarged view of a portion corresponding to a portion C of the compressor according to the seventh embodiment.

FIG. 20 is an enlarged view of a portion corresponding to a portion B of the compressor according to the eighth embodiment.

FIG. 21 is an enlarged view of a portion corresponding to a portion B of the compressor according to the eighth embodiment.

[Explanation of symbols]

4 ... shaft, 9 ... movable scroll (movable part), 15 ...
Suction chamber, 16: fixed scroll, 22: bypass hole, 2
3 ... Spool (valve element), 25 ... Coil spring (elastic member), 27, 28 ... Communication path.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Mitsuo Inagaki 14 Iwatani, Shimowakaku-cho, Nishio-shi, Aichi Prefecture Inside Japan Automotive Parts Research Institute (72) Inventor Shigeki Iwanami 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Shares 3H029 AA02 AA04 AA05 AA15 AB03 BB00 BB21 BB31 BB44 BB52 CC14 CC16 CC24 3H039 AA02 AA04 AA12 BB00 BB02 BB07 BB22 CC01 CC07 CC12 CC28 CC30

Claims (6)

[Claims] 1. A variable displacement compressor for sucking and compressing a fluid by increasing or decreasing the volume of a working chamber (V) formed by a movable scroll (9) and a fixed scroll (16). Shaft (4) for rotating scroll (9)
A bypass hole (22) for communicating the working chamber (V) with the fluid suction side; opening and closing the bypass hole (22), and rotating the shaft (4) via an elastic member (25). A valve body (23) forcibly vibrating by receiving the generated excitation force; and a communication path (27, 28) for communicating the space (24) where the valve body (23) vibrates and displaces with the fluid suction side. And a variable displacement compressor. 2. A variable displacement compressor for sucking and compressing a fluid by increasing or decreasing the volume of a working chamber (V) formed by a movable scroll (9) and a fixed scroll (16). Shaft (4) for rotating scroll (9)
A bypass hole (22) for communicating the working chamber (V) with the fluid suction side; opening and closing the bypass hole (22), and rotating the shaft (4) via an elastic member (25). A valve element (23) forcibly vibrating by receiving an exciting force generated therewith; and a maximum amplitude of the valve element (23) by colliding with the valve element (23) when the valve element (23) vibrates. (26) that mechanically regulates the pressure, and a buffer (30) that reduces a collision force generated when the valve body (23) collides with the stopper (26). Variable displacement compressor. 3. A variable displacement compressor for sucking and compressing a fluid by increasing or decreasing the volume of a working chamber (V) formed by a movable scroll (9) and a fixed scroll (16). Shaft (4) for rotating scroll (9)
A bypass hole (22) for communicating the working chamber (V) with the fluid suction side; opening and closing the bypass hole (22), and rotating the shaft (4) via an elastic member (25). A valve body (23) forcibly vibrating by receiving the exciting force generated therewith, and an end in the vibration direction of the valve body (23) in a space (24) where the valve body (23) vibrates and displaces. Lid (26)
The elastic member (25) is located between the lid (26) and the valve body (23), and is a non-linear elastic member whose elastic coefficient increases as the amount of deformation increases. A variable displacement compressor characterized by the following. 4. A variable displacement compressor for sucking and compressing a fluid by enlarging or reducing the volume of a working chamber (V) formed by a movable scroll (9) and a fixed scroll (16). Shaft (4) for rotating scroll (9)
A bypass hole (22) for communicating the working chamber (V) with the fluid suction side; opening and closing the bypass hole (22), and rotating the shaft (4) via an elastic member (25). A valve body (23) that forcibly vibrates by receiving an accompanying exciting force; a vibration space (24) in which the valve body (23) vibrates and displaces; and a space (24a, 24b) formed by the valve body (23). 2
4b) and a communication passage (27,
28), and a check valve (31) that allows fluid to flow only in one direction in the communication path (27, 28). The space (24a, 24b) includes the valve body. By changing the volume with the vibration displacement of (23), an urging means for applying a force corresponding to the vibration displacement of the valve body (23) to the valve body (23) is configured. Variable capacity compressor. 5. A variable displacement compressor for sucking and compressing a fluid by increasing or decreasing the volume of a working chamber (V) formed by a movable scroll (9) and a fixed scroll (16), Shaft (4) for rotating scroll (9)
A bypass hole (22) for communicating the working chamber (V) with the fluid suction side; a valve element (23) that opens and closes the bypass hole (22) and is displaceable with respect to the bypass hole (22). The valve body (23) is formed with a pressure receiving projection (23b) that protrudes in the direction of displacement of the valve body (23) and is displaced integrally with the valve body (23). The displacement space (3) in which the pressure receiving protrusion (23b) slides and displaces.
2) and the space (32a) formed by the pressure receiving projection (23b) constitutes an urging means for applying a force corresponding to the displacement of the valve element (23) to the pressure receiving projection (23b). The valve element (23) receives a force from the urging means via the pressure receiving projection (23b), and receives a vibrating force generated with the rotation of the shaft (4) to forcibly vibrate. A variable displacement compressor characterized by: 6. A variable displacement compressor for sucking and compressing a fluid by increasing or decreasing the volume of a working chamber (V) formed by a movable scroll (9) and a fixed scroll (16). Shaft (4) for rotating scroll (9)
And a bypass hole (22) for communicating the working chamber (V) with the fluid suction side; opening and closing the bypass hole (22) and rotating the shaft (4) via an elastic member (25). A valve body (23) forcibly vibrating by receiving an exciting force generated thereby; a vibration space (24) in which the valve body (23) vibrates and displaces; and a space formed by the valve body (23). (24a, 2
4b) a force corresponding to the vibration displacement of the valve element (23);
A variable displacement compressor characterized by acting on the valve body (23) together with the elastic member (25).