JPH0693978A - Variable volume vane pump - Google Patents

Abstract

PURPOSE:To suppress vibration of a cam ring owing to a pressure in a pump chamber. CONSTITUTION:A rotor 34 and vanes 40A-40C are contained at the inside of a cam ring 26 swung in a side housing 10. A protrusion part 46 is formed on the outer peripheral part of the cam ring 26 and first and second pressure control chambers 60L and 60R are formed on both sides thereof. First and second holes H1 and H2 communicated with the first pressure control chamber 60A and third and fourth holes 3 and 4 communicated to the second pressure control chamber 60R are formed between a fluid suction groove 20 and a liquid delivery groove 22. Rotor protrusion part 37a and a recessed part 37b to open and close the holes 1-H4 are formed in a rotor 34. Rocking of the cam ring owing to a pressure in the pump chamber 29 is suppressed by means of a difference in an internal pressure between the two pressure control chambers 6OL and 60R occasioned by opening and closing thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable displacement vane pump used as an oil supply pump or the like.

[0002]

2. Description of the Related Art As a variable displacement vane pump as described above, for example, the one disclosed in Japanese Patent Laid-Open No. 3-271579 is known.

As shown in FIG. 15, this pump has a pump housing 80 having a fluid suction groove 81 and a fluid discharge groove 82, a cam ring 83 is provided in the pump housing 80, and a rotor is provided inside the cam ring 83. 8
4 are provided. A plurality of vanes 85 are mounted on the outer peripheral portion of the rotor 84 so as to be able to move forward and backward in the radial direction,
The rotor 84 is rotationally driven while these vanes 85 are in sliding contact with the inner peripheral surface 86 of the cam ring 83. The cam ring 83 is swingable around a portion 87 which is an outer peripheral portion thereof and is close to the fluid discharge groove 82. By this swing, the center O _{2 of the} cam ring 83 and the rotation center O ₁ of the rotor 84 are formed. The amount of eccentricity increases and decreases. The space between the outer peripheral surface of the cam ring 83 and the inner peripheral surface of the pump housing 80 has a primary pressure chamber 91 communicating with the fluid suction groove 81 and a secondary pressure chamber communicating with the fluid discharge groove 82 via a passage 88. The pump ring is provided with a spring 93, and the elastic force of the spring 93 causes the cam ring 83 to increase in the amount of eccentricity and reduce the volume of the secondary pressure chamber 92. It is energized. Further, the fluid discharge groove 82
And discharge passage 97 communicating with the outside of the pump housing 9
6, a spool 94 having an orifice portion and a spring 95 are inserted.
By being urged to the upstream side in the communication passage 96 by the above, the communication passage 96 and the passage 88 are blocked by the outer peripheral surface of the spool 95.

According to such a pump, the rotor 8 is
By the rotational drive of No. 4, the fluid such as oil is sucked from the fluid suction groove 81 to the portion between the inner peripheral surface of the cam ring 83 and the outer peripheral surface of the rotor 84, and the spool 9 is discharged from the fluid discharge groove 82.
When the discharge flow rate reaches a constant value when the discharge flow rate reaches a constant value through the fourth orifice part, the discharge rate can be kept constant by the swing of the cam ring 83 as follows.

First, in a region where the number of revolutions of the rotor per unit time (hereinafter referred to as the number of revolutions) is low, the discharge flow rate increases substantially in proportion to the number of revolutions of the rotor. When the discharge amount increases and reaches a predetermined amount Qo, the flow resistance of the fluid passing through the orifice portion of the spool 94 increases, and the spool 94 is acted on by the force of the pressure difference between the upstream and downstream sides of the spool 94. It moves to the downstream side against the elastic force, and the communication passage 96 and the passage 88 communicate with each other, and as a result, the force based on the pressure in the secondary pressure chamber 92 becomes the pressure in the primary pressure chamber 91 and the spring 93. The cam ring 83 is swung in the direction in which the amount of eccentricity decreases by the difference between the forces. The displacement of the pump chamber 89 is reduced by the amount of the swing, and thereafter, the discharge flow rate is prevented from exceeding the predetermined flow rate Qo regardless of the increase in the rotor rotation speed.

[0006]

DISCLOSURE OF THE INVENTION In the above pump,
The total number of vanes 85 mounted on the rotor 84 may be set appropriately (seven in the example of FIG. 15), but this reduces the cost of the pump and is caused by the sliding resistance between the vanes 85 and the inner peripheral surface of the cam ring 83. In order to suppress an increase in driving torque, it is preferable to reduce the number of vanes 85 as much as possible. However, as the number of vanes 85 decreases, the force that unnecessarily swings the cam ring 83 due to the internal pressure of the pump chamber 89 increases, which causes a problem of promoting the vibration of the cam ring 83.

The principle will be described with reference to FIGS. 16 (a) to 16 (f). Note that, in FIG. 16, for convenience, the swing center O ₃ of the cam ring 83 is shown on the side closer to the fluid suction groove 81, but as shown in FIG. 15, the swing center O ₃ is also on the discharge side. The principles are almost the same. In addition, in FIG. 16, three vanes 85A, 85B, and 85C are used as 12 vanes.
The separation angle from the downstream end of the fluid suction groove 81 in the vane rotation direction to the upstream end of the fluid discharge groove 82 (the direction of the arrow in FIG. 15) in the vane rotation direction is approximately equal to the separation angle between the vanes. Example set equal, vane 8
The pump chamber formed between 5A and 85B is 89C, and the pump chamber formed between the vanes 85B and 85C is 89A.
The pump chamber formed between the vanes 85C and 85A is 89
It is represented by B.

First, as shown in FIG. 16A, in a state immediately after the vane 85A has passed through the fluid suction groove 81 and immediately after the vane 85B has reached the fluid discharge groove 82, the pump chambers 89C and 89A. Is communicated with the high-pressure fluid discharge groove 82 and the pump chamber 89B is communicated with the low-pressure fluid suction groove 81. Therefore, due to the pressure difference, a diagonal force F ₁ as shown in the figure acts on the cam ring 83. Therefore, this force F ₁
Of the X-direction component (a component in the direction orthogonal to the straight line connecting the cam ring swing center O ₃ and the cam ring center O ₂ ) by the moment about the cam ring swing center O ₃ based on the force Fx, the cam ring 83 is forced to swing. Will be done.

Next, as shown in FIG. 2B, when the vane 85B reaches the substantial center in the left and right direction of the cam ring, the pressures in the pump chambers 89A to 89C are balanced and the cam ring 83 swings. A longitudinal force F ₁ that does not occur acts. Then, as shown in FIG.
Becomes closer to the end of the fluid suction / discharge groove 82, the force F
The direction ₁ inclines in the direction opposite to that in the case of FIG. 9A, and a force Fx for swinging the cam ring 83 in the opposite direction is generated.

Then, as shown in FIG. 3D, immediately after the vane 85B has passed through the fluid discharge groove 82 and the vane 85C has reached the fluid suction groove 81, the pump chamber 89A sucks low-pressure fluid. In order to communicate with the groove 81, the force F ₁ acting on the cam ring 83 suddenly changes its direction, and a force Fx in the direction opposite to the cam ring swinging force Fx in the state of FIG. Thereafter, as shown in FIG. 8E, when the vane 85C reaches substantially the center in the left and right direction of the cam ring, the pressures in the pump chambers 89A to 89C are balanced to prevent the cam ring 83 from swinging in the vertical direction. The force F ₁ of the force F ₁ acts, and thereafter, as the vane 85C approaches the end of the fluid suction / intake groove 81, the direction of the force F ₁ inclines in the opposite direction to that in the case of FIG. A force Fx that causes the cam ring 83 to swing in the opposite direction to the above is generated.

As described above, the moment around the cam ring swing center O ₃ caused by the cam ring swing force Fx generated due to the pump chamber pressure periodically fluctuates, so that the cam ring 83 vibrates, and the discharge flow rate and discharge This causes inconveniences such as pressure pulsation and noise, and moreover, such a variation in pressure distribution becomes more remarkable as the number of vanes 85 decreases. For this reason, conventionally, the number of vanes is unavoidably increased in order to suppress the above-mentioned vibration, which greatly hinders the cost and reduction of the required drive torque.

In view of such circumstances, it is an object of the present invention to provide a variable displacement vane pump capable of effectively suppressing the vibration of the cam ring due to the pump chamber pressure while reducing the total number of vanes. To do.

[0013]

According to the present invention, a pump housing, a cam ring swingably provided in the pump housing, and a pump chamber provided in the cam ring and an inner peripheral surface of the cam ring are provided. A rotor that is rotatably driven in the formed state, and a plurality of vanes that are provided on the outer peripheral portion of the rotor so as to be able to advance and retreat in the radial direction and that rotate with the rotor while the radially outer end portion makes sliding contact with the inner peripheral surface of the cam ring. And a fluid suction passage and a fluid discharge passage opening into the pump chamber are formed in the pump housing,
The opening separation angle, which is the separation angle from the downstream end in the rotor rotation direction of the fluid suction passage opening to the upstream end in the rotor rotation direction of the fluid discharge passage opening, is set to be substantially equal to the separation angle between the vanes, and the rotation of the rotor causes the fluid Is sucked into the space between the inner peripheral surface of the cam ring and the outer peripheral surface of the rotor through the fluid suction passage, is pressurized and then discharged from the fluid discharge passage, and is accompanied by rocking of the cam ring. In the variable displacement vane pump configured so that the eccentric amount between the center of the cam ring and the rotation center of the rotor changes, and the discharge flow rate of the fluid from the fluid discharge passage increases or decreases with the change in the eccentric amount, A protrusion is provided on the outer peripheral portion of the cam ring, and the first pressure is surrounded by the outer peripheral surface of the cam ring and the inner peripheral surface of the pump housing and faces the protrusion from the upstream side in the rotor rotation direction. A control chamber, a second pressure control chamber surrounded by an outer peripheral surface of the cam ring and an inner peripheral surface of the pump housing and facing the protruding portion from the downstream side in the rotor rotation direction, and the first pressure control opening to the pump chamber. A first hole and a second hole communicating with the chamber and a third hole and a fourth hole opening in the pump chamber and communicating with the second pressure control chamber are formed, and an outer peripheral portion of the rotor is formed. In addition, the rotor protrusions that protrude outward in the radial direction to close the holes and the recesses that are formed between the rotor protrusions and open the holes are alternately formed, and the rotor and the vanes rotate. The pressure difference between the pressure in the first pressure control chamber and the pressure in the second pressure control chamber, which fluctuates with the above, becomes a force for suppressing the force for rocking the cam ring due to the pressure in the pump chamber. Shape of each hole, rotor protrusion, and recess It is obtained by setting the fine arrangement position (claim 1).

More specifically, according to the present invention, the first vane from when an arbitrary vane passes the downstream end of the fluid suction passage opening in the rotor rotation direction until it advances an angle of about 1/4 of the opening separation angle.
In the period of, the first hole is opened and leads to the fluid discharge passage,
The fourth hole is opened to communicate with the fluid suction passage, the second hole and the third hole are closed, and the vane has passed the first period and has an angle of about 1/4 of the opening separation angle. In the second period before proceeding, the first hole and the fourth hole are closed,
The second hole is opened to communicate with the fluid suction passage, the third hole is opened to communicate with the fluid discharge passage, and the vane is about ¼ of the opening separation angle after the second period. In the third period until the angle advances, the first hole is opened and communicates with the fluid discharge passage, and the fourth hole is opened and communicates with the fluid suction passage,
In the fourth period after the second hole and the third hole are closed and the vane passes through the third period and advances by an angle of about ¼ of the opening separation angle, Hole and fourth
Hole is closed and the second hole is opened to communicate with the fluid intake passage,
The shapes and arrangement positions of the holes, the rotor protrusions, and the recesses are set so that the third holes open and communicate with the fluid discharge path, and the first pressure control chamber pressure and the second pressure control in each period. The first pressure is adjusted so that the magnitude of the moment around the swing center of the cam ring due to the pressure difference from the room pressure is about half the maximum value of the moment that swings the cam ring due to the inner pressure of the cam ring. The pressure receiving area of the protruding portion from the control chamber and the second pressure control chamber is set (claim 2).

Further, according to the present invention, in the first period from when an arbitrary vane passes the downstream end of the fluid suction passage opening in the rotor rotation direction to when it advances an angle of about 1/6 of the opening separation angle, No. 1 is opened and communicates with the fluid discharge passage.
Of the second hole and the third hole
All of the holes are closed and the vanes are closed during the second period after the vane has passed the first period until it advances through about 1/6 of the opening separation angle. In the third period after the period elapses until the angle advances by about 1/6 of the opening separation angle, the first hole and the fourth hole are closed, the second hole is opened, and the fluid suction passage is opened. In the fourth period from when the vane passes the third period to when it advances an angle of about ⅙ of the opening separation angle, The first hole opens to the fluid discharge passage, the fourth hole opens to the fluid suction passage, the second hole and the third hole close, and the vane opens the fourth period. After passing, about 1 / of the opening separation angle
In the fifth period before advancing the angle of 6, all holes are closed, and in the sixth period after the vane passes the fifth period and advances by about 1/6 of the opening separation angle. , The first hole and the fourth hole are closed, the second hole is opened to communicate with the fluid suction passage, and the third hole is opened to communicate with the fluid discharge passage, the rotor projections, And setting the shape and arrangement position of the recess, and during the first period,
First in the third period, the fourth period, and the sixth period
The magnitude of the moment around the swing center of the cam ring based on the differential pressure between the pressure control room pressure and the second pressure control room pressure is about 2 which is the maximum value of the moment that swings the cam ring due to the cam ring inner pressure. 1/3 above to be / 3
The pressure receiving area of the protrusion from the pressure control chamber and the second pressure control chamber is set (claim 3).

Further, according to the present invention, in the first period from when an arbitrary vane passes the downstream end of the fluid suction passage opening in the rotor rotation direction until it advances an angle of about 1/6 of the opening separation angle, The first hole opens to the fluid discharge passage, the fourth hole opens to the fluid suction passage after the first period, and the second hole and the third hole are closed. About 1 of the opening separation angle after the vane has passed the first period.
The first hole and the third hole are closed in the second period until the angle of / 6 is reached, and the fourth hole is closed before the second period is finished. From the beginning of the period, the second hole is opened and communicates with the fluid suction passage, and the vane passes through the second period and advances to about 1/6 of the opening separation angle. In the period of 3, the first hole and the fourth hole are closed, and at a time point before the end of the third period, the second hole is closed, the third hole is opened, and the fluid discharge path is opened. In the fourth period from when the vane passes the third period to when it advances the angle of about ⅙ of the opening separation angle, the first hole opens and leads to the fluid discharge passage, After the start of the fourth period, the fourth hole is opened to communicate with the fluid suction passage, the second hole and the third hole are closed, and the vane is The first hole and the third hole are closed in the fifth period after passing the period 4 and before advancing the angle of about 1/6 of the opening separation angle, and after the start of the fifth period, the first hole and the third hole are delayed. 2 holes open to the fluid suction passage, the 4th hole closes before the end of the 5th period, and the vane is about 1/6 of the opening separation angle after the 5th period. In the sixth period before proceeding, the first hole and the fourth hole are closed, and the second hole is closed and the third hole is closed before the end of the sixth period. The shapes and positions of the holes, the rotor protrusions, and the recesses are set so as to open and communicate with the fluid discharge passage, and the first period, the third period, the fourth period, and the sixth period are also set. The magnitude of the moment around the swing center of the cam ring based on the pressure difference between the first pressure control room pressure and the second pressure control room pressure at The pressure receiving area of the projecting portion from the first pressure control chamber and the second pressure control chamber is set so that it is about 2/3 of the maximum value of the moment that causes the cam ring to swing due to the internal pressure of the cam ring. (Claim 4).

In each of the above-mentioned pumps, the number of vanes is not particularly limited, but it is particularly effective when three vanes are mounted on the outer peripheral portion of the rotor at 120 ° intervals (claim 5).

[0018]

In the pump according to the present invention, the rotor is rotationally driven in the cam ring, whereby the fluid is sucked into the cam ring through the fluid suction passage, and the fluid is pressurized and then passed through the fluid discharge passage. It is discharged to the outside.

During such operation, as the rotor and the vane rotate, the rotor protrusions and recesses formed on the rotor alternately pass through the holes, thereby opening and closing the holes. First on both sides of the protrusion leading to the hole
The pressure control chamber and the second pressure control chamber are appropriately connected to the fluid suction passage or the fluid discharge passage. Along with this communication, the pressure in both pressure control chambers fluctuates, and due to the pressure difference, the cam ring swinging force caused by the pump chamber pressure is suppressed.

More specifically, in the vane pump according to the second aspect, the first hole is opened in the first period and the third period to communicate with the fluid discharge passage, so that the pressure in the first pressure control chamber is increased. The pressure in the second pressure control chamber is reduced by opening the fourth hole and communicating with the fluid suction passage. This allows
A pressure difference occurs between the two pressure control chambers, and due to this pressure difference, a rocking suppression moment in a direction opposite to the rocking moment due to the pump chamber pressure is generated. On the other hand, in the second period and the fourth period, the second hole is opened and communicates with the fluid suction passage to reduce the pressure in the first pressure control chamber, and the third hole is opened to open the fluid discharge passage. Second by going to
The pressure in the pressure control chamber is increased. Due to this pressure difference, a rocking suppression moment in the opposite direction to the rocking moment due to the pump chamber pressure is generated. Moreover, since the absolute value of the rocking suppression moment is set to about 1/2 of the maximum value of the rocking moment caused by the pump chamber pressure,
As will be described later, the maximum value of the force that finally swings the cam ring is almost halved, and the frequency of the fluctuation is increased to about twice.

Further, in the vane pump according to the third and fourth aspects, since the holes are opened and closed in the first period to the sixth period, the pressure difference between the pressure control chambers is the same as in the vane pump according to the second aspect. Occurs, and the cam ring swinging force due to the pump chamber pressure is suppressed. Moreover, the rocking suppression moment due to the pressure difference is about 2/3 of the maximum value of the magnitude of the moment around the cam ring rocking center that rocks the cam ring due to the cam ring internal pressure, so that it will be described later. , The maximum value of the swinging cam ring is about 1 /
It is reduced to 3, and the frequency of the fluctuation is increased by about 3 times.

[0022]

An embodiment of the present invention will be described with reference to FIGS.

The illustrated variable displacement vane pump is provided with a side housing 10, and a front plate 12 and a rear plate 14 as shown in FIG. 2 are attached to the front and rear of the side housing 10 to form a pump housing. A pump shaft 16 penetrates the central portion of the rear plate 14 to face the inside of the pump housing. The pump shaft 16 is connected to a drive source (not shown) and is connected to the rear plate 14 side via a bearing 18. It is rotatably supported.

A fluid suction groove (fluid suction passage opening) 20 and a fluid discharge groove (fluid discharge passage opening) 22 are formed in the front plate 12 and the rear plate 14. Both grooves 20, 22 are open in the pump housing, and the fluid suction groove 20 communicates with the fluid suction port 19 (FIG. 2).

In this pump housing, a cam ring (swing ring) 2 is provided at a position facing both passages 20 and 22.
6 is provided, and front and rear side surfaces thereof are covered with the front plate 12 and the rear plate 14. An outer peripheral portion of the cam ring 26, which is the rotation center of the pump shaft 16 (that is, the rotation center of a rotor 34 described later) O ₁
A substantially circular pivot portion 28 that protrudes outward in the radial direction is formed at a portion (lower end portion in the illustrated example) opposite to the fluid discharge groove 22. This pivot part 28
Is fitted in a recess 30 of substantially the same shape formed at the lower end of the side housing 10, whereby the cam ring 26 can be swung with the center point of the pivot portion 28 as the swing center C, and Due to this swing, the cam ring 2 with respect to the rotation center O ₁ of the pump shaft 16
The eccentricity amount of the center O ₂ of 6 increases and decreases.

A rotor 34 is provided inside the pump chamber 29 inside the cam ring 26. This rotor 34
As shown in FIG. 2, has an inner ring-shaped portion 35 having a width smaller than that of the side housing 10, and an outer ring-shaped portion 37 having substantially the same width as that of the side housing 10. Are also connected via a narrow connecting portion 36. The inner ring-shaped portion 35 is externally fitted to the pump shaft 16 having an irregular cross section, so that the rotor 34 as a whole rotates integrally with the pump shaft 16 in the direction of arrow A in FIG.

On the outer peripheral portion of the outer ring-shaped portion 37, a plurality of (six in the illustrated example) rotor projecting portions 37a projecting radially outward are formed intermittently and at equal intervals. A recess 37b is formed between the portions 37a. The setting of the specific shapes of the rotor protrusion 37a and the recess 37b will be described in detail later.

On the outer ring-shaped portion 37, a plurality of vanes are arranged at equal intervals so as to penetrate the outer ring-shaped portion 37 in the radial direction. In this embodiment, three vanes 40A, 40
B and 40C are arranged at a substantially central position of the rotor projecting portion 37a at 120 ° intervals, and can be individually advanced and retracted in the radial direction. These vanes 40A, 40B, 40C
The vane projecting rings 42 are provided on the left and right sides of the connecting portion 36 on the inner side of the vane 40, and as the rotor 34 rotates, the vanes 40A, 40B, 40C have their own centrifugal force. The vane projecting ring 42 projects radially outward, and the outer end surface of the vane projecting ring 42 is in sliding contact with the inner peripheral surface 27 of the cam ring 26.

At the outer peripheral portion of the cam ring 26, which is opposite to the pivot portion 28 across the rotor rotation center O ₁ , a protruding portion 46 is provided so as to project radially outward. The foot of the protrusion 46 on the upstream side in the rotor rotation direction (see FIG.
In the left foot), a shoulder portion 56L is provided, and in the foot at the downstream side of the protruding portion 46 in the rotor rotation direction (the right foot in FIG. 1), the shoulder portion 56L is provided.
Each R is formed. Both shoulder portions 56L, 56R are in contact with the inner peripheral surface of the side housing 10, and in the space outside the cam ring 26, a primary pressure chamber 47 is formed between the shoulder portion 56L and the pivot portion 28, and the shoulder portion 56L, 56R is formed. A secondary pressure chamber 48 is formed between the portion 56R and the pivot portion 28.

In the side housing 10, a first pressure control chamber 60L is formed in a portion adjacent to the upstream side of the protrusion 46 in the rotor rotation direction, and in a portion adjacent to the downstream side of the protrusion 46 in the rotor rotation direction. Is the second pressure control chamber 6
0R is formed. The spring 32 is press-fitted into the second pressure control chamber 60R. On the other hand, the first
A step portion 25 is formed at a predetermined position of the side housing 10 of the pressure control chamber 60L, and normally, the spring 3 is formed.
The projecting portion 46 is pressed against the stepped portion 25 by the elastic force of 2, and the spring 32 is prevented from swinging in a direction in which the volume of the primary pressure chamber 47 is further reduced.

In the fluid discharge groove 22, a long groove 23 extends in the rotation direction from the downstream end of the rotor in the rotation direction, and the long groove 23 reaches a position where it is opened in the secondary pressure chamber 48. A fluid discharge port 24 communicating with the outside of the pump housing is formed in the secondary pressure chamber 48. On the other hand, the inside of the primary pressure chamber 47 is in a state of being isolated from the fluid discharge groove 22. In addition, the fluid discharge groove 2 starts from the downstream end 20a of the fluid suction groove 20 in the rotor rotation direction.
A separation angle (hereinafter, referred to as a groove separation angle) of the second rotor 2 to the upstream end 22a in the rotor rotation direction is set to an angle substantially equal to the separation angle (120 °) between the vanes. Almost at the same time that the vane passes through the downstream end 20a of the fluid suction groove 20 in the rotor rotation direction, the vane preceding the vane is upstream end 2 of the fluid discharge groove 22 in the rotor rotation direction.
2a is reached.

A first cam ring side passage 52 is formed in the projecting portion 46 so as to penetrate the projecting portion 46 and communicate the inside and outside of the cam ring 26. The position where the first cam ring side passage 52 opens in the cam ring 26 is set to a position close to the downstream end of the fluid discharge groove 22 in the rotor rotation direction. On the other hand, in the side housing 10, the protrusion 4
A housing-side passage 54 extending in the circumferential direction is formed on the surface facing the member 6. The shapes and positions of the housing side passage 54 and the first cam ring side passage 52 are shown in FIG.
As shown in (1), the first cam ring side passage 50 is opened in the housing side passage 54 in a state where the projecting portion 46 is pressed against the step portion 25 by the elastic force of the spring 32, and
When the cam ring 26 swings in the clockwise direction in FIG. 1 from this state, the opening area is gradually reduced, and when the swing amount of the cam ring 26 reaches a certain value, the housing side passage 5
4 and the first cam ring side passage 50 are set to be completely cut off.

A second cam ring side passage 68 that connects the inside of the housing side passage 54 and the primary pressure chamber 47 is formed in the protrusion 46.

In the side housing 10, a first hole H1 opening into the pump chamber 29 is provided at a position immediately upstream of the fluid discharge groove 22 in the rotor rotation direction,
Similarly, a second position is provided immediately downstream of the fluid suction groove 20 in the rotor rotation direction, a position directly downstream of the fluid discharge groove 22 in the rotor rotation direction, and a second position is provided immediately upstream of the fluid suction groove 20 in the rotor rotation direction. Hole H2, third hole H3, fourth hole H
4 are provided. Further, the hole HL is formed on the side surface of the first pressure control chamber 60L, and the hole H is formed on the side surface of the second pressure control chamber 60R.
R is provided respectively, the hole HL and the first hole H1 and the second hole H2 are communicated with each other through the communication passage 70L, and the hole HR is connected with the third hole H3 and the fourth hole H4. 70R passage
Are communicated via.

The shapes and positions of the holes H1 to H4, the rotor projection 37a, and the recess 37b are set so as to satisfy the following conditions.

(A) Each of the holes H1 to H4 is connected to the rotor protrusion 37a.
When passing through the hole H1
The holes H1 to H4 are opened when the recess 37b passes, while the holes H1 to H4 are closed. That is, all the holes H1 to
The radius of the circumscribed circle of H4 is smaller than the radius of the rotor protrusion 37a, and larger than the radius of the circumscribed circle of the recess 37b.

(B) The angle from a certain reference position to the downstream end 20a of the fluid suction groove 20 in the vane rotation direction is θo, and the upstream end 22a of the fluid discharge groove 22 in the vane rotation direction from the reference position.
The angle to theta _4, both angles .theta.o, the 4 equally divided angle between _{θ 4 θ 1, θ 2,} θ 3, the area of the angle Shitao～shita ₁ first region, the angle theta ₁ through? ₂ When the area of 1 is a second area, the area of angles θ _{2 to} θ _{3 is} a third area, and the area of angles θ _{3 to} θ _{4 is} a fourth area, an arbitrary vane is During the first period and the third period in the third region, as shown in FIG. 3, the first hole H1 and the fourth hole H4 are opened and the second hole H4 is opened.
In the second period and the fourth period in which the second and third holes H3 are closed and the vane is in the second region and the fourth region,
The first hole H1 and the fourth hole H4 are closed and the second hole H2 is closed.
And the third hole H3 is opened. That is,
Each of the holes H1 to H4 is opened for half of the entire period and closed for half. Therefore, theoretically, the angular width of the vane projecting portion 37a and the angular width of the concave portion 37b should be substantially equal, but in reality, as shown in FIG. Only the vane protrusion 37a is formed wider.

Further, due to the force due to the pressure difference between the internal pressure of the first pressure control chamber 60L and the internal pressure of the second pressure control chamber 60R, the cam ring caused by the pump chamber pressure described above with reference to FIG. The moment (F ₂ × L in FIG. 16) for suppressing the swing of 26 is 1 which is the maximum value of the swing moment caused by the pump chamber pressure.
The pressure receiving area of the projecting portion 46, that is, the projecting portion 46 is the first pressure control chamber 60L and the second pressure control chamber 6
The area facing 0R is set.

Next, the operation of this variable displacement vane pump will be described.

When the rotor 34 is driven to rotate integrally with the pump shaft 16 in the cam ring 26 from the initial state as shown in FIG. 1, the fluid suction port 19 is introduced into the cam ring 26.
The fluid is sucked through the fluid suction groove 20, and after being pressurized, the fluid is sequentially discharged through the fluid discharge groove 22, the long groove 23, the secondary pressure chamber 48, and the fluid discharge port 24 to the outside of the pump housing.

In the region where the rotation speed of the rotor 34 is low, the discharge flow rate increases as the rotation speed increases.
As the discharge flow rate increases, the fluid discharge groove 22 to the long groove 2
The flow resistance of the fluid until it is introduced into the secondary pressure chamber 48 through 3 is increased, so that the pressure in the region immediately upstream of the long groove 23 in the cam ring 26 is increased in the secondary pressure chamber 48. Higher than pressure. Therefore, the pressure in the primary pressure chamber 47, which communicates with the above region, also rises, and the force based on the differential pressure between the pressure in the primary pressure chamber 47 and the pressure in the secondary pressure chamber 48 causes the spring 32 to spring. When the generated force is overcome, the cam ring 26 is swung by the difference in the force in the direction in which the eccentricity between the cam ring center O ₂ and the rotor rotation center O ₁ decreases, which reduces the displacement of the pump chamber 29. It is regulated that the discharge flow rate increases as the rotor speed increases. Further, as the cam ring 26 swings, the opening area of the first cam ring side passage 52 with respect to the housing side passage 54 gradually decreases, so that an excessive increase in pressure in the primary pressure chamber 47 is suppressed.

The discharge flow rate is controlled by swinging the cam ring 26 with such a change in the number of revolutions. In addition to such meaningful swing, the pump ring 29 has a pump chamber 29. An unnecessary rocking force acts due to the internal pressure. That is, as shown in FIGS. 16 (a) to 16 (f), the pump chamber 29 between the passage of an arbitrary vane through the fluid suction groove 20 and the arrival of the fluid discharge groove 22.
The force F ₁ acts on the cam ring 26 due to the internal pressure of the cam ring 26, and the direction and magnitude of the cam ring rocking force Fx, which is the component in the X direction, changes with the rotation of the vane. Specifically, the vane has a moment that causes the cam ring to swing due to the cam ring swinging force Fx.
While passing through the fourth region, it changes as shown by the solid line in FIG.
Attempts to vibrate the cam ring 26.

However, in the vane pump shown in this embodiment, the pressure in the pump chamber 29 is appropriately adjusted through the first hole H1 to the fourth hole H4 to the first pressure control chamber 60L and the second pressure control chamber 60L.
Since the pressure is transmitted to the pressure control chamber 60R, a moment for preventing the vibration is generated in the protruding portion 46 of the cam ring 26.

The rotor 34 and the vanes 40A-4A
A description will be given along with the rotation of 0C. First, in a first period from when one vane, for example, the vane 40A, passes the fluid suction groove downstream end 20a and advances by ¼ of the groove separation angle, the second hole H2 While the third hole H3 is closed by the rotor protrusion 37a, the first hole H1 is opened and communicates with the high pressure fluid discharge groove 22, and the fourth hole H4 is opened and the low pressure fluid suction groove 20. Lead to Here, the first hole H1 communicates with the first pressure control chamber 60L through the communication passage 70L, and the fourth hole H4 receives the second pressure through the communication passage 70R.
Since it communicates with the pressure control chamber 60R, the first pressure control chamber 6
The pressure in 0L is higher than that in the second pressure control chamber 60R, and due to the pressure difference, the cam ring 26 has a rocking moment F ₂ × L () which is opposite to the rocking moment caused by the internal pressure of the pump chamber 29. (See FIG. 16). Moreover, the magnitude of this swinging restraining moment is 1/2 of the maximum value of the magnitude of the swinging moment due to the relationship with the pressure receiving area of the projecting portion 46. Therefore, this swinging restraining moment is shown in FIG.
As indicated by the broken line.

Next, in the second period after the vane 40A passes through the first region and advances by 1/4 of the groove separation angle, the first hole H1 and the fourth hole H4. Is closed by the rotor protrusion 37a, the third hole H3 is opened and communicates with the high pressure fluid discharge groove 22, and the second hole H2 is opened and communicates with the low pressure fluid suction groove 20. Here, the second hole H2 communicates with the first pressure control chamber 60L through the communication passage 70L, and the third hole H3 receives the second pressure through the communication passage 70R.
Since it communicates with the pressure control chamber 60R, the first pressure control chamber 6
The pressure in the 0L becomes lower than that in the second pressure control chamber 60R, and due to the pressure difference, the swing suppression moment F ₂ × L opposite to the moment in the first period acts.
In addition, after passing the second period, 1/4 of the groove separation angle
In the third period until the angle is advanced by just the same as in the first period, only the first hole H1 and the fourth hole H4 are opened, and
In the fourth period from the passage of the period of (1) to the advance of 1/4 of the groove separation angle, only the second hole H2 and the third hole H3 are opened as in the second period. As indicated by the broken line 3, the swinging restraining moment opposite to the swinging moment due to the pump chamber pressure is always generated during the first period to the fourth period.

When the swinging moment and the swinging restraining moment are combined, the result is shown by the one-dot chain line in FIG.
As is clear from this figure, finally the cam ring 2
The magnitude of the swinging moment acting on 6 is reduced to about 1/2 of the swinging moment (solid line in the figure) in the conventional pump. For this reason, even if the number of vanes is reduced to three, the cam ring 26 does not generate a large vibration, and the discharge flow rate can be stabilized accordingly. Further, various devices such as actuators to which the working fluid discharged from the vane pump is supplied have a relatively low natural frequency,
When the pulsation frequency of the discharge flow rate is low, it tends to be affected. However, in the vane pump shown in this embodiment, the frequency of the moment for rocking the cam ring is about twice that of the conventional one as shown by the one-dot chain line in FIG. Therefore, there is an advantage that adverse effects on other actuators can be suppressed.

Next, a second embodiment will be described with reference to FIGS. 4 and 5. In this embodiment, the basic configuration of the entire vane pump is the same as that of the first embodiment, but an arbitrary vane advances by 1/6 of the groove separation angle after passing the downstream end 20a of the fluid suction groove 20. The angled period is advanced by a first period, the period advanced by 1/6 of the groove separation angle from the first period is advanced by a second period, and the period advanced by 1/6 of the groove separation angle from the second period. The period is a third period, the period advanced by 1/6 of the groove separation angle from the third period is the fourth period, and the period advanced by 1/6 of the groove separation angle from the fourth period. If the sixth period is the fifth period, which is a period obtained by advancing the groove spacing angle by ⅙ from the fifth period, the sixth period is
As shown in the following Table 1 and FIG. 5, the shapes of the holes H1 to H4, the rotor protrusion 37a, and the recess 37b are set so that the holes H1 to H4 can be opened and closed.

[0048]

[Table 1] First period: First hole H1 and fourth hole H4 are opened Second hole H2 and third hole H3 are closed Second period: All holes H1 to H4 are closed 3rd period: 1st hole H1 and 4th hole H4 are closed 2nd hole H2 and 3rd hole H3 are open 4th period: 1st hole H1 and 4th hole H4 are open Second hole H2 and third hole H3 are closed-Fifth period: All holes H1 to H4 are closed-Sixth period: First hole H1 and fourth hole H4 are closed Second hole H2 When the pressure difference between the pressure control chambers 60L and 60R is generated, the magnitude of the moment acting on the cam ring based on the pressure difference is generated due to the pressure in the pump chamber. To make it about 2/3 of the maximum value of swing moment,
The pressure receiving area of the protrusion 46 is set.

In such a vane pump, when the first hole H1 and the third hole H3 are opened, the first pressure control chamber 60L is passed through the first hole H1 and the third hole H3. The second pressure control chamber 60R communicates with the high pressure fluid discharge groove 22, and the second hole H2 and the fourth hole H4.
The second hole H2 and the fourth hole
The first pressure control chamber 60L and the second pressure control chamber 60R communicate with the low pressure fluid suction groove 20 through the hole H4 of
When H4 is closed, it is considered that the pressure in both pressure control chambers 60L and 60R will drop so as to be equal to each other due to leakage through the gap between the front and rear plates 12 and 14 and the cam ring 26 and the like. Both pressure control chambers 60
The fluctuation of the rocking suppression moment based on the pressure difference between L and 60R is approximated by the broken line graph shown in the upper half of FIG. Combining this swinging restraining moment and the swinging moment due to the pump chamber pressure shown by the solid line in the figure, it becomes as shown by the dashed line in the figure.

As is apparent from this figure, according to the vane pump in this embodiment, the maximum value of the moment for swinging the cam ring is about 1 as compared with the conventional one.
The frequency of the moment fluctuation can be increased up to about 3 times.

Next, a third embodiment will be described with reference to FIGS. 6 and 7. In the second embodiment, when all the holes H1 to H4 are closed, the pressure drop in both the pressure control chambers 60L and 60R due to the leak through the gap in the pump is taken into consideration.
When the dimensions of each part of the pump are set with extremely high accuracy and the leak is extremely small, both pressure control chambers 60L,
To reduce the pressure in R, these pressure control chambers 60
It is extremely desirable to positively communicate the inside of L and 60R with the fluid suction side.

Therefore, in this embodiment, as shown in FIG. 6, the second hole H2 and the fourth hole H4 in the second embodiment are elongated holes extending in the circumferential direction, so that the lower half of FIG. As shown in the section, the fourth hole H4 opens in almost the entire period of the first period and the second period and almost the entire period of the fourth period and the fifth period and communicates with the fluid suction groove 20, The second hole H2 is opened and communicates with the fluid suction groove 20 during almost the entire period of the second period and the third period and during the almost entire period of the fifth period and the sixth period. Moreover, the opening timing of the fourth hole H4 is slightly delayed from the start time of the first period and the start time of the fourth period, respectively, and the closing timing of the fourth hole H4 is delayed from that of the second period. It is slightly earlier than the end and the end of the fifth period, and the opening timing of the second hole H2 is slightly delayed from the start of the second period and the start of the fifth period, respectively. The closing timing of the second hole H2 is slightly earlier than the end of the second period and the end of the fifth period, respectively.

According to this structure, the fluid discharge groove 22
In the period (that is, the second period and the fifth period) in which the first hole H1 and the third hole H3, which communicate with each other, are closed (that is, the second period and the fifth period), the low-pressure fluid suction is performed by opening the second hole H2 and the fourth hole H4. By communicating with the groove 20, the pressure in both the pressure control chambers 60L and 60R is surely lowered, and the maximum value of the swinging moment is set to 1
The frequency can be reduced to / 3 and the frequency can be tripled. Moreover, as shown in the lower half of FIG. 7, the second hole H2
Since the opening and closing timing of the fourth hole H4 and the fourth hole H4 is shifted forward and backward from the opening and closing timing of the first hole H1 and the third hole H3,
Hole H2 and the fourth hole H4 are the first hole H1 and the third hole H3.
At the same time, there is an effect that a sudden pressure change due to opening and closing can be avoided and an impact due to this can be prevented beforehand.

Next, a fourth embodiment will be described with reference to FIG.

Here, the radially inner edges of the fluid suction groove 20 and the fluid discharge groove 22 in the second embodiment are equal to or radially outer than the outer peripheral edge of the rotor protrusion 37a of the outer ring-shaped portion 37. The width dimensions of the fluid suction groove 20 and the fluid protrusion groove 22 are reduced until they are positioned, and the first hole H1 and the third hole H1 are formed inside the fluid discharge groove 22.
Hole H3 is provided, and the second hole H2 is provided inside the fluid suction groove 20.
And a fourth hole H4 are provided, and the first hole H1 and the second hole H2 are communicated with the hole HL in the first pressure chamber 60L through the individual communication passages 70L1 and 70L2, respectively. H3
And the fourth hole H4 are respectively connected to the individual communication passages 70R3, 7R7.
It communicates with the hole HR in the second pressure chamber 60R via 0R4.

Even with such an arrangement, the holes H1 to H
By providing 4 in the position shown in the drawing, for example, an opening / closing pattern (lower half of FIG. 5) of each hole H1 to H4 similar to that of the second embodiment can be obtained, and the same effect as that of the same embodiment can be obtained. Obtainable. As described above, there is an embodiment corresponding to each of the first embodiment and the third embodiment. Here, the fifth embodiment corresponding to the third embodiment is shown in FIG.
Illustrations of examples corresponding to the examples are omitted.

However, if the holes H1 to H4 are arranged as shown in the first to third embodiments, the first hole H1 and the second hole H2 are formed in the common communication passage 70L and inside the hole HL. And the third hole H3 and the fourth hole H4 are connected to the common communication passage 70.
There is an advantage that R can communicate with the hole HR. That is, the position of each hole in the present invention is an area deviated from the fluid suction groove 20 and the fluid discharge groove 22, and is located in the pump chamber 2
It can be appropriately set within the region that opens in 9.

The present invention is not limited to the above embodiments, and the following modes can be adopted as examples.

(1) In the above embodiment, the cam ring swing center C is located on the side closer to the fluid suction groove 20, and the protrusion 46 is located on the side closer to the fluid discharge groove 22, but conversely, the cam ring. The present invention can be applied to the case where the swing center C is on the side closer to the fluid discharge groove 22 and the protrusion 46 is on the side closer to the fluid suction groove 20 as in the above.

(2) In the present invention, regardless of the specific number of vanes, even if the number of vanes increases, the separation angle and the groove separation angle are set to be substantially equal, and this angle is set to the first value. No. 1 region-fourth region (first embodiment) or first region-
By dividing into a sixth region (second embodiment and third embodiment) and setting the opening and closing of the first hole H1 to the fourth hole H4 in each region in the same manner as in each of the above embodiments, The same effect can be obtained. For reference, 5 vanes 40
When using A, 40B, 40C, 40D, 40E,
The structures of the vane pumps corresponding to the first, second, third, fourth, and fifth embodiments are shown in FIGS. 10, 11, 12, 13, and 14, respectively. deep.

(3) In the present invention, the total number of holes is not limited to four and may be more. For example, each of the first hole H1 to the fourth hole H4 in the present invention may be divided into a plurality of holes.

(4) In the present invention, the spacing angle between the vanes and the groove spacing angle do not have to be set exactly equal to each other. For example, the groove spacing angle is a little larger than the vane spacing angle. In addition, the narrow groove is extended from the upstream end of the fluid discharge groove in the vane rotation direction to the fluid suction groove side, and the two vanes are present in the area corresponding to the groove separation angle. Even in the structure in which the region sandwiched between the two is slightly communicated with the fluid discharge groove side through the narrow groove,
The present invention can be applied.

(5) The opening / closing timings of the holes H1 to H4 in the first to third embodiments do not necessarily have to be precisely assigned to ¼ or ⅙, and the swinging moment is suppressed. It may be shifted back and forth for a minute time as long as possible.

[0064]

As described above, according to the present invention, the first pressure control chamber and the second pressure control chamber are formed on both sides of the protruding portion provided on the outer peripheral portion of the cam ring, and the first pressure control chamber and the fourth pressure control chamber are formed. Through the holes, and by opening and closing these holes by the rotor protrusions and recesses provided on the rotor outer peripheral portion, a pressure difference is created between the pressure control chambers. Since the swinging force caused by the room pressure is suppressed, the vibration of the cam ring caused by the pump room pressure can be suppressed with a simple structure without using a special device. Therefore, the pulsation of the discharge flow rate can be suppressed and stable operation can be realized while reducing the number of vanes. Particularly, by reducing the number of vanes to three as described in claim 5, the cost of the entire pump and the torque required for driving the rotor can be significantly reduced.

More specifically, according to the vane pump of the second aspect, the maximum value of the moment for swinging the cam ring is set by appropriately setting the opening / closing timing of each hole in the first to fourth regions. Can be reduced to about 1/2. Further, the frequency of the oscillating force can be increased up to about twice, and the pulsation frequency of the discharge flow rate is also increased accordingly, so that the effect of the pulsation on other devices can be reduced. is there.

Further, according to the vane pump of the third aspect, by appropriately setting the opening / closing timing of each hole in the first region to the sixth region, the maximum value of the swinging moment is about 1/3. And the frequency of the swinging force is reduced to about 3
There is an effect that can be increased up to twice.

Further, according to the vane pump of the fourth aspect, the opening and closing timing of the second hole and the fourth hole is extended more than that of the vane pump of the third aspect, so that the fluid leakage in the pump is extremely reduced. Second, even if there is little
The pressures in both pressure control chambers can be reliably reduced during the period 5 and the period 5. Therefore, there is an effect that the maximum value of the swinging moment can be more surely reduced and the frequency can be increased. Moreover, since the opening / closing timings of the second hole and the fourth hole are shifted forward and backward with respect to the opening / closing timings of the first hole and the third hole, the second hole and the fourth hole are set to the first There is an effect that it is possible to avoid a sudden pressure fluctuation that occurs when opening and closing the hole or the third hole at the same time, and to prevent the occurrence of impact due to this pressure fluctuation.

[Brief description of drawings]

FIG. 1 is a front view showing a state in which a front plate is removed in a variable displacement vane pump according to a first embodiment of the present invention.

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

FIG. 3 is a diagram showing the opening / closing timing of each hole in the variable displacement vane pump and fluctuations of the swinging moment associated therewith.

FIG. 4 is a front view showing a state in which a front plate is removed in a variable displacement vane pump according to a second embodiment of the present invention.

FIG. 5 is a diagram showing the opening / closing timing of each hole in the variable displacement vane pump and fluctuations of the swinging moment associated therewith.

FIG. 6 is a front view showing a state in which a front plate is removed in a variable displacement vane pump according to a third embodiment of the present invention.

FIG. 7 is a diagram showing the opening / closing timing of each hole in the variable displacement vane pump and fluctuations of the swinging moment associated therewith.

FIG. 8 is a front view showing a state in which a front plate is removed in a variable displacement vane pump according to a fourth embodiment of the present invention.

FIG. 9 is a front view showing a state in which a front plate is removed in a variable displacement vane pump according to a fourth embodiment of the present invention.

FIG. 10 is a front view showing a modified example of the variable displacement vane pump.

FIG. 11 is a front view showing a modified example of the variable displacement vane pump.

FIG. 12 is a front view showing a modified example of the variable displacement vane pump.

FIG. 13 is a front view showing a modified example of the variable displacement vane pump.

FIG. 14 is a front view showing a modified example of the variable displacement vane pump.

FIG. 15 is a front view showing an example of a conventional vane pump.

16 (a) to 16 (f) are explanatory diagrams showing cam ring swinging force generated due to pump chamber pressure in the vane pump.

[Explanation of symbols]

10 Side Housing (Constitutes Pump Housing) 12 Front Plate (Constitutes Pump Housing) 14 Rear Plate (Constitutes Pump Housing) 20 Fluid Intake Groove (Opening of Fluid Intake Path) 20a Downstream End of Fluid Intake Groove in Rotor Rotation 22 Fluid Discharge groove (opening of fluid discharge path) 22a Rotor rotation upstream end of fluid discharge groove 26 Cam ring 27 Cam ring inner peripheral surface 28 Pivot portion 34 Rotor 37a Rotor protruding portion 37b Recessed portion 40A, 40B, 40C vane 46 Projected portion 60L No. 1 Pressure control chamber 60R Second pressure control chamber 70L, 70R, 70L1, 70L2, 70R3, 70
R4 communication passage H1 first hole H2 second hole H3 third hole H4 fourth hole

Claims (5)

[Claims] 1. A pump housing, a cam ring swingably provided in the pump housing, and a cam chamber that is provided in the cam ring and that forms an inner peripheral surface of the cam ring and is rotationally driven. A rotor and a plurality of vanes that are provided on the outer peripheral portion of the rotor so as to be able to advance and retreat in the radial direction thereof, and that have a plurality of vanes that rotate with the rotor while being in sliding contact with the inner peripheral surface of the cam ring. A fluid suction passage and a fluid discharge passage that open into the pump chamber are formed, and an opening separation angle that is a separation angle from the downstream end of the fluid suction passage opening in the rotor rotation direction to the upstream end of the fluid discharge passage opening in the rotor rotation direction is a vane. The rotation angle of the rotor is set to be almost equal to each other, and the rotation of the rotor causes the fluid to pass through the fluid suction passage and the outer peripheral surface of the cam ring and the outer surface of the rotor. The air is sucked into the space between the peripheral surface and the pressure, and then discharged from the fluid discharge passage, and the eccentric amount between the center of the cam ring and the rotation center of the rotor changes as the cam ring swings. In the variable displacement vane pump configured so that the discharge flow rate of the fluid from the fluid discharge passage increases or decreases in accordance with the change in the eccentric amount,
A projecting portion is provided on the outer peripheral portion of the cam ring, the first pressure control chamber is surrounded by the outer peripheral surface of the cam ring and the inner peripheral surface of the pump housing and faces the projecting portion from the upstream side in the rotor rotation direction, the outer peripheral surface of the cam ring and the pump. A second pressure control chamber that is surrounded by the inner peripheral surface of the housing and faces the protrusion from the downstream side in the rotor rotation direction; a first hole that opens into the pump chamber and communicates with the first pressure control chamber; A second hole and a third hole and a fourth hole which are opened in the pump chamber and communicate with the second pressure control chamber are formed, and the outer peripheral portion of the rotor is projected outward in the radial direction thereof. The rotor protrusions that close the holes and the recesses that are formed between the rotor protrusions and open the holes are alternately formed, and the first pressure that fluctuates as the rotor and vanes rotate. Pressure in control room and second pressure The shapes and positions of the holes, rotor protrusions, and recesses are set so that the pressure difference between the pressure in the control chamber and the pressure in the pump chamber suppresses the force that rocks the cam ring. A variable displacement vane pump characterized by the above. 2. The variable displacement vane pump according to claim 1, wherein an arbitrary vane passes through a downstream end of the fluid suction passage opening in the rotor rotation direction, and then about 1 / the opening separation angle is reached.
4, the first hole is opened to the fluid discharge passage, the fourth hole is opened to the fluid suction passage, and the second hole and the third hole are opened. In the second period from when the hole is closed and the vane passes the first period to when it advances the angle of about 1/4 of the opening separation angle, the first period
And the fourth hole are closed, the second hole is opened and communicates with the fluid suction passage, and the third hole is opened and communicates with the fluid discharge passage,
In the third period from when the vane passes the second period to when it advances the angle of about ¼ of the opening separation angle, the first hole is opened and communicates with the fluid discharge passage, and the fourth hole is opened. Hole opens to communicate with the fluid suction passage, the second hole and the third hole are closed, and the vane passes through the third period until it advances about 1/4 of the opening separation angle. In the fourth period, the first hole and the fourth hole are closed, the second hole is opened to communicate with the fluid suction passage, and the third hole is opened to communicate with the fluid discharge passage, The shape and arrangement position of each hole, rotor protrusion, and recess are set, and the magnitude of the moment around the cam ring swing center due to the pressure difference between the first pressure control chamber pressure and the second pressure control chamber pressure during each period. Is the magnitude of the moment that causes the cam ring to swing due to the internal pressure of the cam ring. Variable displacement vane pump, characterized in that setting the pressure receiving area of the protruding portion of about 1/2 and so as to the first pressure control chamber and the second pressure control chamber of a large value. 3. The variable displacement vane pump according to claim 1, wherein an arbitrary vane passes through a downstream end of the fluid suction passage opening in the rotor rotation direction, and then about 1 / the opening separation angle is set.
In the first period until the angle of 6 is reached, the first hole is opened to the fluid discharge passage, the fourth hole is opened to the fluid suction passage, and the second hole and the third hole are opened. All holes are closed and the vanes are in the second period during the second period after the holes are closed and the vane has passed the first period until the vane advances about 1/6 of the opening separation angle. In the third period from when passing through the angle until advancing an angle of about 1/6 of the opening separation angle, the first hole and the fourth hole are closed and the second hole is opened to the fluid suction path. The fourth hole from the passage of the third hole to the fluid discharge passage, and the passage of the vane after passing the third period to advancing an angle of about 1/6 of the opening separation angle.
In the period of, the first hole is opened and leads to the fluid discharge passage,
The fourth hole is opened to communicate with the fluid suction passage, the second hole and the third hole are closed, and the vane has an angle of about 1/6 of the opening separation angle after the fourth period. All holes are closed in the fifth period until the vane advances, and in the sixth period after the vane passes the fifth period and progresses an angle of about 1/6 of the opening separation angle, The first hole and the fourth hole are closed, the second hole is opened to communicate with the fluid suction passage, and the third hole is opened to communicate with the fluid discharge passage. The shape and the arrangement position are set, and the first pressure control chamber pressure and the second pressure in the first period, the third period, the fourth period, and the sixth period are set.
The magnitude of the moment around the swing center of the cam ring based on the differential pressure from the pressure control chamber pressure is about 2/3 of the maximum value of the moment that swings the cam ring due to the inner pressure of the cam ring. A variable displacement vane pump characterized in that a pressure receiving area of the projecting portion from the first pressure control chamber and the second pressure control chamber is set. 4. The variable displacement vane pump according to claim 1, wherein an arbitrary vane passes through a downstream end of the opening of the fluid suction passage in the rotor rotation direction, and then about 1 / of the opening separation angle.
In the first period until the angle of 6 is advanced, the first hole is opened and communicates with the fluid discharge passage, and after the first period is started, the fourth hole is opened and communicated with the fluid suction passage. , The second hole and the third hole are closed, and the second period from when the vane passes the first period to when it advances an angle of about 1/6 of the opening separation angle is the first period. And the third hole are closed, the fourth hole is closed before the end of the second period, and the second hole is opened after the start of the second period and the fluid is opened. The first hole and the fourth hole are closed in the third period from when the vane passes the second period and advances to an angle of about 1/6 of the opening separation angle after communicating with the suction passage. , At the point before the end of the third period, the second
Hole is closed, the third hole is opened and leads to the fluid discharge passage,
In the fourth period from when the vane passes the third period to when it advances the angle of about 1/6 of the opening separation angle, the first hole is opened and communicates with the fluid discharge passage, and the fourth hole is opened. After the start of the period, the fourth hole opens and communicates with the fluid suction passage, the second hole and the third hole close, and the opening separation angle after the vane passes the fourth period. About 1/6
The first hole and the third hole are closed in the fifth period before advancing the angle of, and the second hole is opened after reaching the fifth period to reach the fluid suction passage after the fifth period, The fourth hole is closed before the end of the above, and the vane passes through the fifth period and advances to an angle of about 1/6 of the opening separation angle during the sixth period. The fourth hole is closed and the second hole is closed before the end of the sixth period, and the third hole is opened so that each hole, the rotor projection, And setting the shape and disposition position of the recess, and setting the first pressure control chamber pressure and the second pressure control chamber pressure during the first period, the third period, the fourth period, and the sixth period. The magnitude of the moment around the swing center of the cam ring based on the differential pressure causes the cam ring to swing due to the internal pressure of the cam ring. About 2 size maximum of Mento /
A variable displacement vane pump, wherein the pressure receiving area of the protruding portion from the first pressure control chamber and the second pressure control chamber is set so as to be 3. 5. The variable displacement vane pump according to any one of claims 1 to 4, wherein 120 is provided on the outer peripheral portion of the rotor.
A variable displacement vane pump that is equipped with three vanes at intervals.