JPH0374592A - Variable capacity compressor - Google Patents

Abstract

PURPOSE:To prevent the chattering and the like of vanes by providing a control member for controlling the compression start timing by its rotation with back pressure lead-in holes to be communicated with vane grooves when the control member is in a partial operating position so as to lead vane back pressure in and block the lead-in of vane back pressure when the control member is in a busy position. CONSTITUTION:A variable capacity compressor is formed by enclosing a rotor 2, provided with plural vanes advancing/receding in the radial direction, into a cam ring 1, and is provided with a compressed space 12 formed by the circumferential displacement by 180 deg. between the cam ring 1 and the rotor 2. A rear side block 4 is provided with a ring-formed recessed part 26 on its surface on the rotor side, and a ring-formed control member 27 is fitted thereinto. The compression start timing is controlled by the rotation of the control member 27. In this case, the control member 27 is provided with two symmetric back pressure lead-in holes 29 circumferentially displaced by 180 deg.. Each back pressure lead-in hole 29 is communicated with a vane groove when the control member 27 is in a partial operating position, and blocked at the end face of the vane when the control member 27 is in the busy position.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a variable displacement compressor that variably controls the discharge capacity by controlling the compression start timing, and in particular a variable capacity compressor that is designed to prevent vane chattering. Regarding mold compressors.

(Prior Art) Conventionally, in variable capacity compressors, in order to prevent chattering due to a decrease in vane back pressure during compressor operation, and conversely, wear out of vane tips due to introduction of excessive back pressure,
From the start of the suction stroke to the middle of the compression stroke, the hole at the bottom of the vane groove is connected to the back pressure introduction groove formed on the end surface of the rotor side of the side block on one side of the cylinder, so that an intermediate pressure is maintained in the hole at the bottom. While introducing high pressure vane back pressure into the bottom hole, the high pressure vane communicates with the bottom hole and maintains high pressure inside the bottom hole from the time when the communication between the bottom hole and the back pressure introduction groove is cut off until the end of the discharge stroke. It has been proposed that a back pressure oil feed hole for introducing back pressure is provided in the negative side block (Utility Application No. 63-37834).

In this proposed variable displacement compressor, during the period from when the communication between the hole at the bottom of the vane groove and the back pressure introduction groove is cut off until the end of the discharge stroke, both during full operation and during partial operation. The same high-pressure vane back pressure is introduced into the cam ring, and the vane tip is pressed against the inner peripheral surface of the cam ring by the combined force of the high-pressure vane back pressure and centrifugal force, thereby preventing chattering and wear of the vane tip. That's what I'm trying to do.

(Problem to be Solved by the Invention) However, in the above-mentioned proposed technology, as shown in FIG. When this occurs, the vane back pressure Pk suddenly decreases, causing chattering of the vane. This reduction in vane back pressure Pk is partly due to the fact that during Wm, the rotor is biased toward the side block on the negative side, so the gap between the side block on the negative side and the rotor narrows, and back pressure oil is introduced. This is thought to occur because it becomes difficult to The reason why the rotor shifts to one side is that the suction pressure Ps is always applied to the back side of the side block on the other side of the rotating shaft, and when the discharge pressure Pd is low such as during partial operation, the rotor shifts to the negative side. This is because it is pressed against the side block side. In order to counteract such a sudden drop in vane back pressure Pk, it is conceivable to increase the flow rate by increasing the diameter of the back pressure oil feed hole provided in the - side side block. If the rotor is biased toward the side block on the negative side, the effect will be small, and if the rotor is biased toward the side block on the other side, the vane back pressure Pk will become too high, causing the tip of the vane to wear out. In addition, problems such as loss of compressor driving power occur.

The present invention has been made to solve the above problem, and aims to prevent chattering of the vanes due to the shift of the rotor during partial operation, as well as prevent wear of the tips of the vanes during full operation. The purpose of the present invention is to provide a variable capacity compressor with a variable displacement type.

(Means for Solving the Problem) In order to solve the above-mentioned object, the present invention includes a cylinder, a rotor fitted in the cylinder, and a rotor fitted in a vane groove of the rotor so as to be freely protrusive and retractable in a radial direction. In a variable displacement compressor equipped with a plurality of vanes, and a control member that controls the compression start timing by rotation, when the control member is in the -S operating position, it communicates with the vane groove to apply vane back pressure. introduced,
The control member is provided with a back pressure introduction hole that is closed to block introduction of the vane back pressure when the control member is in the fully operational position.

(Function) During partial operation, the back pressure introduction hole provided in the control member communicates with the vane groove, and the vane back pressure is introduced into the vane groove.
Prevents reduction in vane back pressure. On the other hand, during full operation, the back pressure introduction hole is closed and the introduction of vane back pressure is blocked, thereby preventing an increase in vane back pressure.

(Example) Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

FIG. 1 is a longitudinal sectional view showing a variable capacity vane type compressor according to an embodiment of the present invention.

Figures 1 and 21! As shown in FIG. 1, the variable displacement vane type compressor includes a cam ring 1 having a substantially elliptical inner peripheral surface 1a, and front side blocks fixed to both end surfaces of the cam ring 1 so as to close the end surfaces thereof. 3
and a rear side block 4, a 1W cylindrical rotor 2 rotatably housed in the cylinder, and a front head 5 and a rear head 6 fixed to the outer end surfaces of both side blocks 3 and 4, respectively. and a rotating shaft 7 of the rotor 2. The rotating shaft 7 is rotatably supported by bearings 8 and 9 provided on both side blocks 3 and 4, respectively.

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

Between the inner peripheral surface 1a of the cam ring l and the outer peripheral surface of the rotor 2, two compression spaces 1 are formed symmetrically and offset by 180 degrees in the circumferential direction.
2.12 is defined. The rotor 2 is provided with a plurality (for example, five) of vane grooves 13m to 13s along its radial direction at equal intervals in the circumferential direction, and these vane grooves 131 to 13! ! Vanes 141 to 14s are fitted therein so as to be freely retractable along the radial direction.

In the rear side block 4, there is a suction boat shown in No. 1131! 5 are provided symmetrically and offset by 180 degrees in the circumferential direction. Each suction boat 15 penetrates through the rear side block 4 in the thickness direction, and the suction chamber opening and the compression spaces 12, 12 are communicated with each other via each suction boat 15.

As shown in FIG. 2, discharge boats 16, 16 are bored in the outer peripheral wall of the cam ring I at symmetrical positions in the circumferential direction. The cam ring with the discharge boat 16.16! A discharge valve cover 17 having a valve stop portion 17a is fixed to the outer peripheral wall of the discharge valve with bolts 18. A discharge valve 19 held on the side of the discharge valve cover 7 is interposed between the outer peripheral wall of the cam ring l and the valve stop portion 17a, and the discharge valve 19 opens when receiving discharge pressure. and set the discharge boat i6 to ilJ[J
There is something like that. Furthermore, as shown in FIG. 9, the cam ring l has communication passages 20 that communicate with each discharge boat 16 when each discharge valve 19 is opened, and the front side block 3 communicates with each communication passage 20. communication path 21
are formed at symmetrical positions in the circumferential direction. and,
When each discharge boat 16 opens, the compressed refrigerant gas in the compression space 12 is transferred to the discharge boat 16, the communication passage 20,
21, the liquid is discharged sequentially through the discharge chamber 10 and the discharge port 5a.

As shown in the first factor, the bottoms of the discharge chamber 10 and the suction chamber 11 are oil reservoir chambers 10a and lOb, and the oil reservoir chambers IO
b is isolated from the suction chamber inlet by a wall portion 11b. Each oil reservoir chamber 10a, 10b includes a front side block 3,
Each survey path 3a of the cam ring l and rear side block 4,
・Communicate via lb and 4a.

As shown in FIGS. 1 and 4, two back pressure oil feed holes 23ε are provided in the rotor side end surface of the front side block 3, corresponding to the two back pressure introduction grooves 22 and the valley groove.

Each back pressure introduction groove 22 is for introducing a vane back pressure Pk, which is an intermediate pressure between the discharge pressure Pd and the suction pressure Ps, into the holes 1310 to 13so at the bottom of each of the vane grooves 13t to 13s, and starts from the start of the suction stroke. The hole 13u at the bottom until the middle of the compression stroke
It is arranged at a symmetrical position in the circumferential direction communicating with ox1360. Each back pressure introduction groove 22 corresponds to each compression space 12, and each back pressure introduction groove 22 communicates with each other through a narrow passage 22a.

Each back pressure sending hole 23 is a bottom hole 13so to 13s.

This is to introduce a high vane back pressure Pk that is slightly lower than the discharge pressure I'd and higher than the intermediate vane back pressure 1'. The back pressure oil supply hole 23 is located at the bottom hole 13+o~
Two of them are arranged at symmetrical positions in the circumferential direction communicating with the bottom holes 1.3so to 13so from the time the communication between the back pressure introduction groove 22 and the back pressure introduction groove 22 is cut off until the end of the discharge stroke. Each back pressure oil feed hole 23 is bored so that oil in the 1lllff chamber tea receives the discharge pressure Pd and is introduced through the orifice 24 and the survey path 3b in the front side block 3.

Furthermore, a bearing chamber 3c is defined in the front side block 3 around the wheel bearing 8. The bearing chamber 3c includes a passage 7a in the rotating shaft 7 and a passage 4d in the rear side block 4.
It communicates with the suction chamber IN through a passageway 3d in the front side block 3, and with the compression space 12 through a passageway 3d in the front side block 3.

As a result, part of the refrigerant gas in the suction chamber ti is transferred to the passage 4.
d, 7a, the compression space 1 through the bearing chamber 3c and the passage 3d.
2, and the bearing 8 is lubricated.

On the other hand, in the rear side block 4, a bearing chamber 4b is defined around the bearing 9. The bearing chamber 4b communicates with the oil sump chamber Job through the passage 4C and the orifice 25, and the ih of the oil sump chamber tob is introduced into the bearing chamber 4b under the discharge pressure Pd, thereby lubricating the bearing 9. This is what will happen.

1st [1! As shown in FIG. 1 and FIG. 5, the rear side block 4 is provided with an annular recess 26 on its rotor 2 side surface, and a ring-shaped recess 26 as shown in FIG. A control member 27 is fitted so as to be rotatable in forward and reverse directions as shown in FIGS. 1 and 6. The control member 2
Arc-shaped notches i' 1128, 28 are provided on the outer peripheral edge of 7 at symmetrical positions offset by 180 degrees in the circumferential direction.

The control member 27 has two back pressure introduction holes 29 arranged one in the circumferential direction.
It is placed symmetrically at an 80 degree angle.

Each back pressure introduction hole 29 is for compensating for a decrease in the vane back pressure Pk, and when the control member 27 is in a partially operating position where the vane back pressure Pk decreases, the vanes m13+~ passing by due to the rotation of the rotor 2 13s, and when the control member 27 is in the full operating position where the discharge pressure Pd is high and the vane back pressure does not decrease, each of the rotating vanes 141-
It is set in such a position that it is closed by the end face of 1411.

Each back pressure introduction hole 29 includes a bearing chamber 4b and a passage 4c.

It communicates with the 7111 reservoir chamber 10b via the orifice 25, and the bleed water in the η11 reservoir chamber lOb is introduced in response to the discharge pressure Pd, thereby compensating for a decrease in vane back pressure. On one side of the control member 27, protruding pressure receiving portions 30° 30 are integrally provided and symmetrically offset by 180 degrees in the circumferential direction. The space is divided into two pressure working chambers (not shown).

A low suction pressure Ps is introduced into one side of the volume pressure section, and a high pressure created by introducing the discharge pressure 1)d from the compression space 12 into the other side through an orifice (not shown). A certain control pressure Pc is applied to each of them. The R1
1JI'f pressure Pc is controlled by an on-off valve machine m (FIG. 9) so that the suction pressure Ps is at a predetermined set line. The control member 27 is rotated by the difference between the resultant force of the suction pressure Ps supplied to one of the pressure working chambers and the torsion coil spring 31, and the control pressure Pc formed in the other pressure working chamber. Controls when compression starts. That is, the control member 27
As the control pressure Pc increases, it rotates toward the fully operated position shown in FIG. 2, and as the control pressure Pc decreases, it rotates toward the partial operation position shown in FIG. 3.

In this full operating position, the front end 28a of each notch 28 of the control member 27 is at the rearmost position in the rotor rotational direction, and the compression start time is the earliest, allowing the refrigerant to be trapped between two successive vanes. The gas volume becomes maximum and the discharge capacity becomes maximum.

- the front end 2 of each notch 28 in the partially activated position;
8a is located at the position closest to nII in the rotor rotational direction, has the latest compression start time, and the volume of refrigerant gas trapped between two successive vanes is the minimum, resulting in the minimum discharge capacity.

Next, the operation of the variable capacity vane compressor having the above configuration will be explained.

In each compression space 12, refrigerant gas is sucked from the suction chamber 11 through the suction boat 15 and the notch 28 of the control member, respectively, into the compression space 12 between the two vanes after the phase 13 on the suction stroke. The compression stroke begins when the rear vanes in the rotor rotational direction of the two vanes pass through the front end 28a of each notch 28, thereby cutting off the communication between the compression space 12 between the two vanes and the suction boat 15. is started, and after the compression stroke is completed, the discharge stroke is started.

The suction stroke is a section from the at position to the a2 position when the control member 27 is in the full operation position shown in FIG. When the unit is in operation, this is the section from position 81 to position 82'. Further, the start timing of the compression stroke becomes later as the control member 27 rotates from the fully operated position shown in FIG. 2 to the partially operated position shown in FIG. 3, and thereby the discharge capacity decreases continuously.

During the rotation of the rotor 2, each vane 141 to 14s is connected to each vane groove 13 through the back pressure introduction groove 22 shown in FIGS. 1 and 4.
Receives the vane back pressure Pk introduced into the holes 131o to 135° at the bottom of t to 13s, and the tips of each vane 14+ to 145 are pressed against the inner peripheral surface 1a in the cam ring 1 by this vane back pressure Pk and centrifugal force. .

Due to the rotation of the rotor 2, for example, the hole 131o at the bottom of the vane groove
When the groove moves radially outward and communication with the back pressure introducing groove 22 is cut off, the hole 13+o at the bottom communicates with the corresponding back pressure sending hole 23. Yuzu having a discharge pressure I'd in the oil sump chamber 10a is introduced into the bottom hole 131o through the orifice 24, the force 11 path 3b and the back pressure feed hole 23, thereby causing a high-pressure vane in the bottom hole. A back pressure Pk is created. The tip of the vane is pressed against the inner peripheral surface 1a of the cam ring 1 by the high vane back pressure Pk and centrifugal force.

During partial operation, as the control member 27 rotates, the back pressure introduction hole 29 moves to a position radially inward from the base end of the vane 14+, as shown in FIG. 7(a). Therefore, as the rotor rotates, the back pressure introduction hole 29 communicates with the lower part of the vane groove 13t of the passing vane 14+, and the n;
The vane groove passes through the orifice 25, oil passage 4c, bearing 4b, and back pressure introduction hole 29! It was introduced in 31. Therefore, even when the A-Y 2 is biased toward the front side block 3, it is possible to prevent the vane back pressure Pk from decreasing as shown in FIG. It is pressed against 1a. Therefore, chattering of the vanes 14s to 14s can be prevented.

On the other hand, during full operation, the back pressure introduction hole 29
Regarding the rotation of the vane 14, as shown in FIG. 7(b),
Move from the proximal end of i to a position where an external force is applied in the radial direction. Therefore, since the rotor rotates and the back pressure introduction hole 29 is blocked by the vane, the introduction of the oil from the oil sump chamber fob into the vane groove is blocked. Therefore, during full operation, no more than necessary vane back pressure Pk is applied to the vane, and the tip of the vane is not strongly pressed against the inner corner surface 1a of the cam ring l. Therefore, wear of the tips of the vanes 141 to 146 can be prevented.

In the above embodiment, the back pressure oil supply hole 23 and the back pressure introduction hole 29 are
We have explained mFli which has both 071
It is also possible to omit this and provide only the back pressure introduction hole 29.

FIG. 9 is a longitudinal sectional view showing a variable capacity vane type pressure line machine according to another embodiment of the present invention.

In the embodiment described above, when the control member is in the full operating position, the back pressure introduction hole 29 is closed by the end face of the vane 14+~14!1, and when the control member is in the fully operated position, the back pressure introduction hole 29 and the vane groove 14+~ 45, and as a result via the orifice 25, the passage 4c and the bearing chamber 4b? The case has been described in which the oil fed into the +11 reservoir chamber 10b is introduced into the vane grooves 13m to 13s through the back pressure introduction hole 29.

In contrast, in this embodiment, as shown in FIG. 9, an orifice 33 that communicates with the discharge chamber IO via a communication passage 20.21 is provided in the cam ring l, and the orifice 33 communicates with the orifice 33 during partial operation. to increase the discharge pressure Pd to the bearing chamber 4b.
A back pressure introduction hole 34 is provided in the I'1FJfs member 27, and the back pressure introduction hole 34 is closed by the cam ring 1 during full operation. As shown in FIG. 1O, the back pressure introduction hole 34 is comprised of a long groove portion 34a formed by counterboring the end surface of the control member 27 on the rotor side, and a communication portion 34b communicating with the long groove portion 34a. As a result, the high-pressure refrigerant gas guided through the orifice 33 passes through the long groove portion 34a and the communication portion 34b to the bearing chamber 4b.
Vane grooves 13 High pressure refrigerant gas is introduced into 13B.

According to this embodiment configured as described above, the same effects as in the embodiment shown in FIG. 1 can be obtained.

(Effects of the Invention) As explained above, according to the variable displacement compressor of the present invention, when the control member is in the partially operating position, it communicates with the vane groove to introduce vane back pressure, and the control member Since the control member is provided with a back pressure introduction hole that is closed and blocks the introduction of the vane back pressure when the rotor is at the full position, the vane back pressure caused by the rotor shifting during partial operation is prevented. This prevents a drop in pressure and prevents chattering of the vanes, and also prevents vane back pressure from increasing excessively when the rotor is in full operation or when the rotor is not biased, thereby preventing wear on the tips of the vanes. can do.

[Brief explanation of drawings]

1 to 7 show a variable displacement vane compressor according to an embodiment of the present invention, FIG. 1 is a vertical sectional view of the variable displacement vane compressor, and FIG. Figure 3 is a cross-sectional view taken along the line ■-■ in the figure, showing the full operating position, and Figure 3 is a cross-sectional view similar to Figure 2, showing the partially operating position, No. 413! 1 is an end view showing the front side block, FIG. 5 is an exploded perspective view of the carrier side block and control member, FIG. 6 is an end view taken along line Vl-■ in FIG. 1, and FIGS. 7(a) and ( b) is a diagram for explaining the relationship between the back pressure introduction hole and the vane, No. 8
The figure is a graph showing the relationship between discharge pressure, compressor rotation speed, and vane back pressure. 1 is a vertical sectional view of a variable displacement vane type compressor, FIG. 10 is a perspective view of a control member, and FIG. 1'1 is a 91! Fig. 12 is a cross-sectional view taken along line XI-XI of I, showing all operating positions;
It is a sectional view similar to the figure, showing a partially operating position. 1... Cam ring, 1a... Inner peripheral surface, 2... Rotor, 3... Front side block (- side block), 4... Rear side block (other side side block), 13+ ~135... Vane groove, 1310
~1350... Hole at the bottom of the vane groove, 14t ~ 145.
... Vane, 27... Control member, 29.34... Back pressure introduction hole, Pk... Vane back pressure.

Claims (1)

[Claims] 1. A cylinder, a rotor fitted in the cylinder,
In a variable capacity compressor comprising a plurality of vanes fitted into vane grooves of the rotor so as to be freely protrusive and retractable in a radial direction, and a control member that controls compression start timing by rotation, the control member is partially operated. The control member includes a back pressure introduction hole that communicates with the vane groove to introduce vane back pressure when the control member is in the vane position, and is closed to block introduction of the vane back pressure when the control member is in the fully operated position. A variable displacement compressor characterized by being installed in a.