JPH087117Y2 - Capacity changer for variable capacity compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a variable capacity device for a variable capacity compressor used as a refrigerant compressor or the like of a vehicle air conditioner.

(Prior Art) As a capacity varying device for a variable capacity compressor of this type, a control pressure formed in a part of the operating position side and in the high pressure operating chamber by a resultant force of an intake pressure and an urging force introduced into the low pressure operating chamber. The control member is urged to the full operating position side by means of the control member and rotates forward and backward between the two positions to control the compression start timing, and the communication between the high pressure working chamber and the suction chamber is controlled to be opened and closed. In a variable displacement vane compressor having an opening / closing valve mechanism for leaking the control pressure in the high pressure working chamber to the suction chamber side, the opening / closing valve mechanism has an opening position for communicating the high pressure working chamber with the suction chamber. A spool valve having a spool valve element that is displaceable between the closed valve position and the closed valve position and that is urged toward the valve closed position side; and an electromagnetic force generated by a control signal from the outside, An electric charge that displaces the spool valve element to the valve opening position side. There is also a spool valve type solenoid valve consisting of a magnetic actuator (Japanese Patent Application No. 2-49277).

In this variable displacement vane compressor, when an ON signal as a control signal is input to the electromagnetic actuator, the spool valve element is displaced to the valve open position side by the electromagnetic force generated by the electromagnetic actuator and controls the inside of the high pressure operating chamber. When the pressure leaks to the suction chamber side and decreases, and when the OFF signal is input, the spool valve element is held in the valve closing position by the urging force, and the control pressure in the high pressure chamber rises. That is, since the control pressure rises during the OFF signal and decreases during the ON signal, the control pressure is controlled to a pressure according to the control signal, and the control member rotates according to this control pressure to rotate the discharge volume. Is controlled.

(Problems to be solved by the invention) However, since the control pressure is released to the suction chamber side by using the spool valve, high airtightness is required to prevent the control pressure from leaking, and therefore a long stroke of the spool valve is required. You will need it. As a result, upsizing of the electromagnetic actuator,
As a result, the size of the compressor is increased as a whole, and at the same time, the power consumption is increased and the responsiveness is poor.

This invention was made in view of such circumstances,
The problem is to provide a variable capacity device capable of preventing the variable capacity compressor from increasing in size.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a valve body that opens and closes a communication passage that communicates from a high pressure working chamber to a suction chamber, and attaches this valve body in a valve closing direction via a plunger. In a displacement variable device of a variable displacement compressor, comprising: a biasing spring; and an electromagnetic actuator that attracts the plunger in the valve opening direction against the biasing force of the spring when the heat load is small, The pressure is applied to one end of the valve element in the valve opening direction and simultaneously to the other end of the valve element in the valve closing direction.

(Operation) As described above, since the pressure of the high-pressure working chamber is applied to the one end of the valve body in the valve opening direction and simultaneously to the other end of the valve body in the valve closing direction, the valve body is opened in the valve opening direction. The pushing force is canceled out, so that the setting force of the spring can be reduced and the valve body can be opened with a small driving force.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 2 to FIG. 4, the variable capacity vane compressor is a cam ring 1 having a substantially elliptical inner peripheral surface 1a.
A cylinder composed of a front side block 3 and a rear side block 4, which are fixed to the both end surfaces of the cam ring 1 so as to close the both end surfaces thereof, and a cylindrical rotor 2 rotatably housed in the cylinder. The main components are a front head 5 and a rear head 6, which are fixed to the outer end surfaces of both side blocks 3 and 4, respectively, and a rotary shaft 7 of the rotor 2.
It is rotatably supported by bearings 8 and 9 provided on 3 and 4, respectively.

A discharge port 5a for the refrigerant gas, which is a heat medium, is formed on the upper surface of the front head 5, and a suction port 6a for the refrigerant gas is formed on the upper rear end surface of the rear head 6. The discharge port 5a communicates with a discharge chamber 10 defined by the front head 5 and the front side block 3, and the suction port 6a communicates with a suction chamber 11 defined by the rear head 6 and the rear side block 4, respectively.

Between the inner surface of the cylinder and the outer peripheral surface of the rotor 2, two compression chambers 12, 12 are symmetrically formed with a 180 ° offset in the circumferential direction. The rotor 2 is provided with a plurality of vane grooves 13 extending along the radial direction thereof at equal intervals in the circumferential direction, and the vanes 14 are respectively fitted in the vane grooves 13 so as to be retractable along the radial direction. ing.

A suction port 15 shown in FIG. 2 is symmetrically provided on the rear side block 4 by being displaced by 180 degrees in the circumferential direction (FIG. 2 shows a longitudinal section taken through an axis of about 90 degrees). Since it is a figure, only one suction port 15 is visible in the figure). Each suction port 15 penetrates in the thickness direction of the rear side block 4, and the suction chamber 11 is inserted through each suction port 15.
And the compression chambers 12, 12 communicate with each other.

As shown in FIGS. 2 to 4, discharge ports 16, 16 are provided on the outer peripheral wall of the cam ring 1 at symmetrical positions in the circumferential direction (in FIG. 2, the same reason as that of the suction port 15). Therefore, only one discharge port 16 is visible). Also,
A discharge valve cover 17 having a valve stop portion 17a is fixed to the outer peripheral wall of the cam ring 1 by a bolt 18, and the discharge valve cover 1 is provided between the outer peripheral wall of the cam ring 1 and the valve stop portion 17a.
A discharge valve 19 held on the 7 side is interposed. Each discharge valve 19
When the valve is opened, a communication passage 20 that communicates with each discharge port 16 is defined by the cam ring 1 and the discharge valve cover 17, and a communication passage 21 that communicates with each communication passage 20 is formed in the front side block 3 in the circumferential direction. Are formed in symmetrical positions. Then, when each discharge port 16 is opened, the compressed refrigerant gas in the compression chamber 12 is discharged through the discharge port 16, the communication passages 20, 21, the discharge chamber 10 and the discharge port 5a sequentially. There is.

As shown in FIGS. 1 and 5, the rear side block 4 is provided with an annular recess 22 on the end surface thereof on the rotor 2 side, and in the annular recess 22, two pressure working chambers 23, 23 are formed. They are symmetrically arranged with a 180 degree offset in the direction. A ring-shaped control member 24 is fitted in the annular recess 22 so as to be rotatable in the forward and reverse directions. The control member 24 is for controlling the compression start timing in each compression chamber 12, and has arcuate cutout portions 24a, 24a (FIGS. 4 and 5) at its outer peripheral edge at symmetrical positions in the circumferential direction.
(See the drawing) is provided, and projecting piece-shaped pressure receiving portions 24b, 24b (see FIG. 5) are integrally provided on one side surface at symmetrical positions in the circumferential direction. These pressure receiving parts 24b, 24
b is slidably fitted in the pressure working chambers 23, 23, respectively. Each pressure working chamber 23 is divided into a low pressure working chamber 23 ₁ and a high pressure working chamber 23 ₂ by each pressure receiving portion 24b. Each low-pressure working chamber 23 ₁ communicates with the suction chamber 11 via each suction port 15,
A low suction pressure P _S is introduced into each of the low pressure working chambers 23 ₁ . On the other hand, one of the high pressure working chambers 23 ₂ communicates with the communication passage 20 through the orifice 25, and each high pressure working chamber 2
3 ₂ and ₂ 3 ₂ communicate with each other via a communication passage 26, whereby a high pressure discharge pressure Pd is introduced into each high pressure working chamber 23 ₂ to form a control pressure Pc. Also, the high pressure working chambers 23 ₂ , 23 ₂
One is, as shown in FIG. 1 and FIG. 5, a communication passage 27 and an opening / closing valve mechanism provided inside the rear side block 4.
It is possible to communicate with the suction chamber 11 via 30.

The control member 24 is biased by the torsion coil spring 28 toward the partial operation position side of the latest compression start timing shown in FIG. 4, and the resultant force of the suction pressure P _s and the biasing force of the torsion coil spring 28 is controlled. Due to the difference from the pressure Pc, the compression start timing is controlled by reciprocal rotation between the full operation position of the earliest compression start timing shown in FIG. 3 and the partial operation position shown in FIG. There is.

As shown in FIG. 2, the torsion coil spring 28 has one end 28a locked in the locking hole 24c of the control member 24 and is formed on the end surface of the boss portion 4a projecting from the side surface of the rear side block 4 opposite to the rotor side. The other end 28b is locked in the formed holding groove 4b.

As shown in FIG. 1, the variable capacity device has a high pressure working chamber 23.
Ball valve 31 that opens and closes the communication passage 27 that leads from ₂ to the suction chamber 11
An axially slidable plunger 32, a coil spring (spring) 33 for urging the ball valve 31 in the valve closing direction via the plunger 32, and a plunger 32 in the coil spring contraction direction when energized. An electromagnetic actuator 34 for attracting, a rod 35 arranged on the axis of the plunger 32 via a ball valve 31, and a cylindrical holder 36 for slidably holding the rod 35 are provided.

The holder 36 is mounted in the fitting hole 37 of the rear side block 4, and the rod 35 is slidably inserted into the small diameter hole 36a of the holder 36. The end of the rod 35 on the ball valve 31 side is a two-stage rod having a smaller diameter. Holder 36
The large-diameter hole 36b communicates with the small-diameter hole 31a, and one end of the plunger 32 is inserted into the large-diameter hole 36b via the ball valve 31. A space 38 forming a part of the communication passage 27 is defined between the holder 36 and the fitting hole 37. Further, the holder 36 is provided with a communication passage 36c that communicates the small diameter hole 36a with the suction chamber 11, and a communication passage 3 that communicates the space 38 with the large diameter hole 36b.
6d is provided. The plunger 32 has a spring receiving hole.
32a is provided, and the coil spring 33 is housed in the spring housing hole 32a.

The electromagnetic actuator 34 is composed of a magnetic core 34a fixed to the rear head 6 and an electromagnetic coil portion 34b mounted on the shaft of the core 34a. The coil spring 3
One end of 3 is in contact with the end surface of the shaft portion of the core 34a, and the spring 33
The elasticity of the plunger 32 is biased toward the small diameter hole 36a side,
The ball valve 31 is pressed against the opening edge of the small diameter hole 36a to close it.

Next, the operation of the capacity varying device of the vane compressor will be described.

When the coil portion 34b of the electromagnetic actuator 34 is in the non-energized state (Fig. 1), the ball valve 31 comes into contact with the opening edge of the small diameter hole 36a via the plunger 32 by the urging force of the coil spring 33, and the valve closed position is maintained. Be drunk In this closed position, the holder 36
Communication between the small diameter hole 36a and the large diameter hole 36b of the
The control pressure Pc in 23 ₂ rises. As a result, FIG. 5 (a)
The control member 24 maintains its full operating position, as shown in FIG.

Seat cross-section area; S ₁ , pressure receiving area of rod 35; S ₂ , setting force of coil spring 33; F _SP , when valve is closed, Pc ・ S ₁ + F _SP > Pc ・ S ₂ + Psmax ・ S _{2 If 1} = S ₂ , the term related to Pc is canceled out and the following equation is obtained.

F _SP ＞ Psmax ・ S ₁ formula In other words, Pc is applied to one end surface of the rod 35, and the rod 35 passes from the space 38 through the communication passage 36 through the ball valve 31.
Since it also applies to the other end of the
Are offset. This eliminates the need to increase the setting force of the coil spring 33.

When the coil portion 34b of the electromagnetic actuator 34 is energized, the electromagnetic force causes the blanker 32 to be attracted to the side opposite to the rod side against the urging force of the coil spring 33, and the ball valve 31 opens (FIG. 5 (b)).

If the electromagnetic valve suction force is F _SV , F _SP <Psmin · S ₁ + F _SV type when the valve is open.

Therefore, since the ball valve 31 can be opened with a small driving force, the electromagnetic actuator 34 can be downsized.

Further, as shown in FIG. 6, the response time of the capacity control may be changed by the change of the load pressure in the device of the present embodiment, as compared with the conventional device which does not use the variable capacity device as in the present embodiment. None, constant regardless of load pressure.

(Effect of the Invention) As described above, according to the variable capacity device of the variable capacity compressor of the present invention, the valve body that opens and closes the communication passage leading from the high pressure working chamber to the suction chamber, and the valve body via the plunger. In a displacement variable device of a variable displacement compressor, comprising a spring for urging in a valve closing direction, and an electromagnetic actuator for attracting the plunger in the valve opening direction against the urging force of the spring when a heat load is small, Since the pressure of the high-pressure working chamber is applied to one end of the valve body in the valve opening direction and at the same time is applied to the other end of the valve body in the valve closing direction, the force pushing the valve body in the valve opening direction is canceled, Therefore, the setting force of the spring can be reduced, and a large driving force is not required to open the valve body. Therefore, the valve element can be opened and closed by the small-capacity electromagnetic actuator, the compressor can be downsized, and fine control with good responsiveness is possible.

[Brief description of drawings]

1 to 6 show an embodiment of the present invention, FIG. 1 is an enlarged vertical sectional view showing a variable capacity device, and FIG. 2 is a variable capacity vane compressor equipped with the variable capacity device. FIG. 3 is a vertical cross-sectional view shown in FIG. 3, which is a cross-sectional view taken along the line III-III in FIG. 2, in which the control member is in the full operating position, and FIG. 4 is a cross-sectional view similar to FIG. FIG. 5 is a conceptual diagram for explaining the operation of the capacity varying device, FIG. 5A is a diagram when the member is in the fully operating position, and FIG. ) Is a diagram when it is partially in the operating position, and FIG. 6 is a curve diagram showing the operating characteristics of the variable capacity device. 1 …… Suction chamber, 23 ₂ …… High pressure working chamber, 27 …… Communication passage, 31
…… Ball valve, 32 …… Plunger, 35 …… Rod.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. A valve body for opening and closing a communication passage communicating from a high pressure working chamber to a suction chamber, a spring for urging the valve body in a valve closing direction via a plunger, and an urging force of the spring when a heat load is small. In the displacement variable device of the variable displacement compressor, which includes an electromagnetic actuator that attracts the plunger in the valve opening direction against the above, when the pressure of the high pressure working chamber is applied to one end of the valve body in the valve closing direction. At the same time, a variable capacity compressor variable capacity device is characterized in that the other end of the valve element is added in a valve closing direction.