JP6901960B2 - Vane pump - Google Patents

Description

The present invention relates to a vane pump.

Conventionally, as described in Patent Document 1, for example, a housing in which a pump chamber is formed, a vane arranged in the pump chamber, a rotor for rotating the vane, and both ends in the longitudinal direction of the vane are provided. Vane pumps with caps are known. The cap is formed with a contact surface that contacts the inner wall surface of the housing. When the vane rotates as the rotor rotates, the contact surface of the cap is pressed against the inner wall surface of the housing. As a result, the space between the inner wall surface of the housing and the cap is sealed.

Japanese Unexamined Patent Publication No. 2015-152003

Lubricating oil is supplied to the pump chamber for the purpose of suppressing wear of the contact surface of the cap. Therefore, lubricating oil adheres to the inner wall surface of the housing and the like. Here, as the vane rotates, the cap moves while pushing away the lubricating oil, so that the cap receives a force from the lubricating oil. If the force received by the cap increases, there is a concern that the drive torque of the vane pump will increase.

A main object of the present invention is to provide a vane pump capable of reducing drive torque.

The present invention includes a housing in which a pump chamber is formed, a vane arranged in the pump chamber and partitioning the pump chamber into a plurality of spaces, a rotor for rotating the vane, and both ends in the longitudinal direction of the vane. A seat surface provided on each portion and a cap provided on the seat surface are provided, and when viewed from the direction of the rotation axis of the rotor, the cap is a portion facing the inner wall surface of the housing. Of the facing surfaces, a predetermined region on the tip end side of the cap is a contact surface that abuts on the inner wall surface as the rotor rotates, and the other region is a non-contact surface that does not abut on the inner wall surface. When viewed from the rotation axis direction of the rotor, the tangent line at the end of the non-contact surface on the rotation direction side of the rotor on the rotation direction side is inclined toward the contact surface side with respect to the seat surface. doing.

In the present invention, when viewed from the rotation axis direction of the rotor, the tangent line at the end of the cap facing the inner wall surface on the rotation direction side of the rotor is the seating surface that receives the cap. It is inclined toward the contact surface side. Therefore, when viewed from the direction of the rotation axis of the rotor, the force received by the cap from the lubricating oil when the vane rotates can be reduced as compared with the configuration in which the tangent line is orthogonal to the seat surface. As a result, the drive torque of the vane pump can be reduced.

The block diagram of the vane pump which concerns on 1st Embodiment. FIG. 1 is a cross-sectional view taken along the line II-II of FIG. The figure which shows the state which the cap is in contact with the seat surface of a vane. Perspective view of the cap. The figure which shows the state which the cap which concerns on a comparative example is in contact with a seat surface. The figure which shows the state which the cap which concerns on 2nd Embodiment is in contact with a seat surface. The figure which shows the state which the cap which concerns on 3rd Embodiment is in contact with a seat surface. The figure which shows the state which the cap which concerns on 4th Embodiment is in contact with a seat surface.

<First Embodiment>
Hereinafter, the first embodiment in which the vane pump of the present invention is embodied will be described with reference to the drawings. The vane pump is fixed to the internal combustion engine of an automobile, for example, to generate a negative pressure in the braking booster of the braking device.

The vane pump 10 will be described with reference to FIGS. 1 to 4.

The vane pump 10 includes a housing 11. The housing 11 is made of, for example, a metal material (for example, aluminum), and has a base portion 11a, a peripheral wall portion 11b, and a cover portion 11c. Note that FIG. 1 is a view of the vane pump 10 viewed from the direction of the rotation axis of the rotor 14 with the cover portion 11c removed from the vane pump 10.

A flat surface for partitioning the pump chamber 13 is formed in the base portion 11a. The peripheral wall portion 11b is a portion that rises from the peripheral edge of the flat surface of the base portion 11a and forms an annular shape. An annular ring groove 11d is formed at an end of the peripheral wall portion 11b opposite to the base portion 11a in the direction in which the wall surface extends. The ring groove 11d is provided with an O-ring 12 which is a sealing member. A cover portion 11c is provided at an end portion of the peripheral wall portion 11b opposite to the base portion 11a in the direction in which the wall surface extends. The inner surface of the cover portion 11c is a flat surface. An O-ring 12 seals between the end of the peripheral wall portion 11b and the cover portion 11c. The space surrounded by the inner surface of the base portion 11a, the inner wall surface of the peripheral wall portion 11b, and the inner surface of the cover portion 11c is defined as the pump chamber 13. A rotor 14, a vane 20, and a cap 40 are arranged in the pump chamber 13.

The rotor 14 has a hollow cylindrical shape. A guide groove 14a extending in the radial direction of the rotor 14 is formed at one end of the rotor 14 in the longitudinal direction. The guide groove 14a is provided with a vane 20 so as to be slidable along the groove 14a. The other end of the rotor 14 in the longitudinal direction is connected to a shaft portion 15 provided outside the housing 11 through an opening formed in the base portion 11a. The shaft portion 15 has a columnar shape. The camshaft of the internal combustion engine is connected to both ends of the shaft portion 15 in the longitudinal direction on the side opposite to the side where the rotor 14 is provided via the coupling 16.

The rotor 14 is provided at a position deviated from the center of the pump chamber 13 when viewed from the direction of the rotation axis. Specifically, a part of the outer peripheral surface is always in contact with a part of the inner wall surface of the peripheral wall portion 11b. It is provided in a state of being. An opening communicating with the suction passage 17 is formed on the rotation direction side of the rotor 14 with respect to the contact portion between the rotor 14 and the peripheral wall portion 11b in the peripheral wall portion 11b. The suction passage 17 is a passage that communicates with the negative pressure space of the brake booster and sucks gas from the space into the pump chamber 13. The suction passage 17 is provided with a suction-side check valve (not shown) for opening and closing the passage 17 and holding the negative pressure in the negative pressure space of the braking booster, for example, when the internal combustion engine is stopped. Has been done.

A discharge passage 18 is formed in the base portion 11a near the contact portion between the rotor 14 and the peripheral wall portion 11b in the peripheral wall portion 11b. The discharge passage 18 is a passage for discharging gas from the pump chamber 13 to the outside thereof. The discharge passage 18 is provided with a discharge side check valve 19 for opening and closing the passage 18 and preventing a backflow of gas from the outside to the pump chamber 13.

The vane 20 has an elongated shape and is made of, for example, a synthetic resin. The portion of the vane 20 facing the cover portion 11c comes into contact with the inner surface of the cover portion 11c. The portion of the vane 20 facing the inner surface of the base portion 11a abuts on the inner surface of the base portion 11a.

At both ends of the vane 20 in the longitudinal direction, accommodating holes 21 extending in the longitudinal direction are formed. In the present embodiment, two accommodating holes 21 are formed at both ends of the vane 20. Of the inner wall surfaces of the vanes 20 forming the accommodation holes 21, the pair of inner wall surfaces facing each other in the rotation direction of the rotor 14 are parallel. Further, seating surfaces 23 with which the cap 40 abuts are formed at both ends of the vane 20 in the longitudinal direction.

A refueling passage 30 is formed in the shaft portion 15. The refueling passage 30 is composed of a passage extending in the longitudinal direction of the shaft portion 15 and a passage extending from the passage in the radial direction of the shaft portion 15 to the outer peripheral surface of the shaft portion 15. The lubricating oil supplied from the oil supply passage 30 flows into the pump chamber 13 through the gap between the shaft portion 15 and the base portion 11a.

Caps 40 are provided at both ends of the vane 20 in the longitudinal direction. The cap 40 is made of, for example, a synthetic resin, and includes a main body portion 41 and a guide portion 42 accommodated in the accommodating hole 21. The main body 41 is a portion extending in the direction of the rotation axis of the rotor 14. The main body 41 has a semicircular portion when viewed from the direction of the rotation axis of the rotor 14. The portion of the main body 41 that faces the inner surfaces of the cover portion 11c and the base portion 11a is a cover facing surface 41b that abuts on the facing inner surfaces. When the cap 40 is viewed from the longitudinal direction of the vane 20, the cap 40 does not protrude from the vane 20.

When viewed from the rotation axis direction of the rotor 14, in the present embodiment, the axis extends in the longitudinal direction of the vane 20 and is the central axis of the cap 40 (the line shown by the alternate long and short dash line in FIG. 3, which corresponds to a virtual line). The cap 40 has a symmetrical shape based on the above. When viewed from the direction of the rotation axis of the rotor 14, a predetermined region on the tip end side of the cap 40 of the facing surface which is a portion of the cap 40 facing the inner wall surface of the peripheral wall portion 11b becomes the peripheral wall portion as the rotor 14 rotates. It is a contact surface 46a that abuts on the inner wall surface of 11b. The portion of the contact surface 66a that actually contacts the inner wall surface of the peripheral wall portion 11b changes according to the rotation position of the rotor 14.

When viewed from the rotation axis direction of the rotor 14, the region other than the contact surface 46a of the facing surface, which is the portion of the cap 40 facing the inner wall surface of the peripheral wall portion 11b, does not abut on the inner wall surface of the peripheral wall portion 11b. It is a non-contact surface. Of the non-contact surfaces, the surface on the rotation direction side is the first non-contact surface 46b, and the surface on the side opposite to the rotation direction is the second non-contact surface 46c.

When viewed from the direction of the rotation axis of the rotor 14, the facing surface has an arc-shaped portion centered on the center point A0 and a linear portion connected to both ends of the arc-shaped portion. The center point A0 is located on the central axis of the cap 40 extending in the longitudinal direction of the vane 20. Of the arcuate portion, the portion from the first point A1 to the second point A2 is the contact surface 46a. The angle between the straight line connecting the first point A1 and the center point A0 and the center axis of the cap 40 and the angle between the straight line connecting the second point A2 and the center point A0 and the center axis of the cap 40 are each other. The angles are the same, and specifically, the values are in the range of 30 ° to 45 °, for example. The first non-contact surface 46b is a portion of the arc-shaped portion on the rotation direction side of the contact surface 46a and a linear portion connected to the portion. The second non-contact surface 46c is a portion of the arc-shaped portion on the side opposite to the rotation direction of the contact surface 46a and a linear portion connected to the portion.

Of the portion of the main body 41 that faces the vane 20, the portion that is not connected to the guide portion 42 is a seating surface 41a that comes into contact with the seating surface 23. The seating surface 41a is formed in pairs with the guide portion 42 of the portion facing the vane 20 in the main body portion 41. In a state where the seating surface 41a of the cap 40 is in contact with the seating surface 23 of the vane 20, the portion of the cap 40 on the vane 20 side of the seating surface 41a is the guide portion 42.

When viewed from the rotation axis direction of the rotor 14, the thickness dimension between the first non-contact surface 46b and the seating surface 41a in the central axis direction of the cap 40 is the rotation direction side of the first non-contact surface 46b. It becomes larger toward the contact surface 46a from the end. Further, when viewed from the rotation axis direction, the thickness dimension between the second non-contact surface 46c and the seating surface 41a in the central axis direction of the cap 40 is opposite to the rotation direction of the second non-contact surface 46c. It becomes larger toward the contact surface 46a from the side end.

The leg portion 43 is a portion of the guide portion 42 that partially protrudes in the longitudinal direction of the vane 20 toward the bottom portion 22 of the accommodating hole 21. The legs 43 are formed in the same number (two) as the number of accommodating holes 21 formed at both ends of the vane 20. Of the portion on the tip end side of the guide portion 42, the portion where the leg portion 43 is not provided is arcuate. Three arc-shaped portions of the guide portion 42 are formed with the leg portion 43 interposed therebetween. The vane 20 is formed with a receiving portion 24 that abuts on each arc-shaped portion of the guide portion 42. Each receiving portion 24 has an arc shape.

Of the inner wall surfaces of the vanes 20 forming the accommodation hole 21, the pair of inner wall surfaces facing each other are parallel to each other. As shown in FIGS. 3 and 4, each of a pair of parallel inner wall surfaces facing each other in the rotation direction of the rotor 14 among the inner wall surfaces of the vane 20 forming the accommodating hole 21 is designated as the facing wall surface. Of the pair of facing wall surfaces, the facing surface on the rotation direction side is referred to as the first facing wall surface 25a, and the facing surface on the side opposite to the rotation direction is referred to as the second facing wall surface 25b. The guide portion 42 is formed with a first guide surface 44a, which is a region facing the first facing wall surface 25a and parallel to the first facing wall surface 25a. The guide portion 42 is formed with a second guide surface 44b which is a region facing the second facing wall surface 25b and parallel to the second facing wall surface 25b.

The region of the first guide surface 44a exposed from the accommodating hole 21 with the rotation of the vane 20 is the first exposed surface, and the region of the second guide surface 44b exposed from the accommodating hole 21 with the rotation of the vane 20. Is the second exposed surface. The exposed portion 42a including the first and second exposed surfaces of the guide portion 42 extends to the cover facing surface 41b. Each of the side surfaces at both ends of the exposed portion 42a in the direction in which the main body portion 41 extends is continuous with the cover facing surface 41b. Therefore, of the side surfaces at both ends of the exposed portion 42a, one abuts on the inner surface of the base portion 11a and the other abuts on the inner surface of the cover portion 11c.

The rotational force from the camshaft is transmitted to the rotor 14 via the shaft portion 15 and the coupling 16. As a result, the rotor 14 rotates. As the rotor 14 rotates, the vane 20 rotates while always dividing the pump chamber 13 into two spaces. Further, when the vane 20 rotates with the rotation of the rotor 14, the cap 40 pops out from the vane 20 in a state where the guide portion 42 is in contact with the inner wall surface forming the accommodating hole 21 due to the centrifugal force acting on the cap 40. As a result, the contact surface 46a of the main body 41 is pressed against the inner wall surface of the peripheral wall portion 11b, and the space between the inner wall surface of the peripheral wall portion 11b and the cap 40 is sealed.

When the seating surface 41a of the cap 40 is in contact with the seating surface 23 of the vane 20 and viewed from the rotation axis direction of the rotor 14, the first non-contact surface 46b is the end of the seating surface 23 on the rotation direction side. It does not protrude from the first virtual straight line L1 connecting the contact surface 46a with the end (A1) on the rotation direction side. Further, when the seating surface 41a is in contact with the seating surface 23 and viewed from the rotation axis direction of the rotor 14, the second non-contact surface 46c is in contact with the end of the seating surface 23 opposite to the rotation direction. It does not protrude from the second virtual straight line L2 connecting the end (A2) of the contact surface 46a on the side opposite to the rotation direction. The condition that the first and second non-contact surfaces 46b and 46c do not protrude from the virtual straight lines L1 and L2 is provided to prevent the first and second non-contact surfaces 46b and 46c from contacting the inner wall surface of the peripheral wall portion 11b.

When the seating surface 41a is in contact with the seating surface 23 and viewed from the rotation axis direction of the rotor 14, the linear portion of the end of the first non-contacting surface 46b on the rotation direction side and the seating surface 23 The second angle θ2 formed by the two is smaller than the first angle θ1 formed by the first virtual straight line L1 and the seating surface 23. Further, when the seating surface 41a is in contact with the seating surface 23 and viewed from the rotation axis direction of the rotor 14, a linear portion of the first non-contacting surface 46b extends to the seating surface 23. Therefore, when viewed from the rotation axis direction of the rotor 14, the tangent line at the end of the linear portion of the first non-contact surface 46b on the rotation direction side is inclined toward the contact surface 46a with respect to the seat surface 23. doing.

When viewed from the rotation axis direction of the rotor 14 with the seating surface 41a in contact with the seating surface 23, the linear portion of the second non-contacting surface 46c opposite to the rotation direction and the seating surface. The fourth angle θ4 formed by 23 is smaller than the third angle θ3 formed by the second virtual straight line L2 and the seating surface 23. Further, in the present embodiment, the first angle θ1 and the third angle θ3 are equal, and the second angle θ2 and the fourth angle θ4 are equal. Each of the second angle θ2 and the fourth angle θ4 is specifically set to a value in the range of, for example, 30 ° to 45 °.

Subsequently, a comparative example will be described with reference to FIG. In FIG. 5, the same components as those shown in FIGS. 3 and 4 are designated by the same reference numerals for convenience.

In the comparative example, the main body of the cap is indicated by 51, and the seating surface is indicated by 51a. In the comparative example, when viewed from the rotation axis direction of the rotor 14, the tangent line and the seat surface at the end of the rotor 14 on the rotation direction side of the contact surface among the facing surfaces facing the inner wall surface of the peripheral wall portion 11b in the cap. It is orthogonal to 51a. Therefore, when the vane 20 rotates, the force that the cap receives from the lubricating oil increases, which in turn increases the driving torque of the vane pump 10.

On the other hand, in the present embodiment, when viewed from the rotation axis direction of the rotor 14, the tangent line at the end of the cap 40 facing the inner wall surface of the peripheral wall portion 11b on the rotation direction side with respect to the contact surface 46a. Is inclined toward the contact surface 46a with respect to the seat surface 23 that receives the cap 40. Therefore, when the vane 20 rotates, the force received by the cap 40 from the lubricating oil can be reduced, and the driving torque of the vane pump 10 can be reduced.

When the seating surface 41a is in contact with the seating surface 23 and viewed from the rotation axis direction of the rotor 14, the first non-contacting surface 46b is the end of the seating surface 23 on the rotation direction side and the contacting surface 46a. It does not protrude from the first virtual straight line L1 connecting the end (A1) on the rotation direction side. As described above, the condition that the first non-contact surface 46b does not protrude from the first virtual straight line L1 is provided in order to prevent the first non-contact surface 46b from coming into contact with the inner wall surface of the peripheral wall portion 11b. On the other hand, the smaller the second angle θ2, the smaller the force that the cap 40 receives from the lubricating oil. Therefore, in the present embodiment, the seating surface 41a is provided so that the force received by the cap 40 from the lubricating oil is reduced while preventing the first non-contact surface 46b from contacting the inner wall surface of the peripheral wall portion 11b. The second angle θ2 is smaller than the first angle θ1 when viewed from the rotation axis direction of the rotor 14 in a state of being in contact with the seat surface 23. Therefore, for example, as compared with a configuration in which the second angle θ2 and the first angle θ1 are equal, the effect of reducing the force received by the cap 40 from the lubricating oil can be enhanced. As a result, the effect of reducing the drive torque of the vane pump 10 can be enhanced.

When viewed from the rotation axis direction of the rotor 14, the first non-contact surface 46b and the second non-contact surface 46c each have a linear portion. Therefore, the area of the seating surface 41a of the cap 40 can be increased, and the surface pressure between the seating surface 23 of the cap 40 and the vane 20 can be reduced. As a result, wear of the seat surface 23 of the cap 40 and the vane 20 can be suppressed.

When viewed from the rotation axis direction of the rotor 14, the cap 40 has a symmetrical shape with respect to the central axis extending in the longitudinal direction of the vane 20. Therefore, it is possible to prevent erroneous assembly of the cap 40 in the manufacturing process of the vane pump 10.

<Second Embodiment>
In each of the following embodiments, the differences from the first embodiment will be mainly described. In each of the following embodiments, the same configurations as those described in the first embodiment are designated by the same reference numerals for convenience.

In the present embodiment, as shown in FIG. 6, the main body portion of the cap is indicated by 61, and the seating surface of the main body portion 61 is indicated by 61a. The contact surface is indicated by 66a, and the first and second non-contact surfaces are indicated by 66b and 66c.

In the present embodiment, when the seating surface 61a of the cap is in contact with the seating surface 23 of the vane 20 and viewed from the rotation axis direction of the rotor 14, the rotation direction of the linear portion of the first non-contact surface 66b The end on the side is arcuate. Therefore, when viewed from the direction of the rotation axis, the tangent line at the end of the linear portion of the first non-contact surface 66b on the rotation direction side is not inclined toward the contact surface 66a with respect to the seat surface 23. .. However, when viewed from the direction of the rotation axis with the seating surface 61a in contact with the seating surface 23, the second angle θ2 formed by the linear portion of the first non-contacting surface 66b and the seating surface 23 is the first. It is smaller than the first angle θ1 formed by the virtual straight line L1 and the seat surface 23. Therefore, it is possible to obtain an effect similar to the effect of the first embodiment.

In the present embodiment, when the seating surface 61a is in contact with the seating surface 23 and viewed from the rotation axis direction of the rotor 14, the linear portion of the second non-contact surface 66c is opposite to the rotation direction. The end on the side is arcuate. Therefore, when viewed from the direction of the rotation axis, the tangent line at the end opposite to the rotation direction of the linear portion of the second non-contact surface 66c is inclined toward the contact surface 66a with respect to the seat surface 23. Not. Further, when viewed from the direction of the rotation axis with the seating surface 61a in contact with the seating surface 23, the fourth angle θ4 formed by the linear portion of the second non-contacting surface 66c and the seating surface 23 is the second. It is smaller than the third angle θ3 formed by the virtual straight line L2 and the seat surface 23.

<Third Embodiment>
In the present embodiment, as shown in FIG. 7, the main body portion of the cap is shown by 71, and the seating surface of the main body portion 71 is shown by 71a. The contact surface is indicated by 76a, and the first and second non-contact surfaces are indicated by 76b and 76c.

In the present embodiment, when viewed from the direction of the rotation axis of the rotor 14, the arcuate portion from the first point A1 to the second point A2 is the contact surface 76a. Of the arcuate portions, the portion on the rotation direction side of the contact surface 76a is the first non-contact surface 76b. When viewed from the rotation axis direction of the rotor 14, the end portion of the first non-contact surface 76b on the rotation direction side is an arc-shaped portion instead of the linear portion. With this arcuate portion, the area of the seating surface 71a can be increased, and the surface pressure between the seating surface 23 of the cap and the vane 20 can be reduced. On the other hand, of the arcuate portion, the portion on the side opposite to the rotation direction from the contact surface 76a is the second non-contact surface 76c. When viewed from the rotation axis direction of the rotor 14, the end portion of the second non-contact surface 76c on the opposite side of the rotation direction is an arc-shaped portion instead of the linear portion. With this arcuate portion, the area of the seating surface 71a can be increased, and the surface pressure between the seating surface 23 of the cap and the vane 20 can be reduced.

In the present embodiment, when the seating surface 71a of the cap is in contact with the seating surface 23 of the vane 20 and viewed from the rotation axis direction of the rotor 14, the arcuate portion of the first non-contact surface 76b is on the rotation direction side. The tangent line at the end of is inclined toward the contact surface 76a with respect to the seat surface 23. Therefore, the effect of reducing the force received by the cap 40 from the lubricating oil can be obtained, and the effect of reducing the driving torque of the vane pump 10 can be obtained.

In the present embodiment, when the seating surface 71a is in contact with the seating surface 23 and viewed from the direction of the rotation axis, the end of the second non-contact surface 76c at the end opposite to the rotation direction of the arcuate portion. The tangent line is inclined toward the contact surface 76a with respect to the seat surface 23.

<Fourth Embodiment>
In the present embodiment, as shown in FIG. 8, the main body portion of the cap is indicated by 81, and the seating surface of the main body portion 81 is indicated by 81a. The contact surface is indicated by 86a, and the first and second non-contact surfaces are indicated by 86b and 86c.

In the present embodiment, all the arcuate portions from the first point A1 to the second point A2 are the contact surfaces 86a. Further, the linear portion connected to the end of the contact surface 86a on the rotation direction side is the first non-contact surface 86b, and the linear portion connected to the end of the contact surface 86a on the opposite side of the rotation direction is the first. 2 Non-contact surface 86c.

In the present embodiment, when the seating surface 81a of the cap is in contact with the seating surface 23 of the vane 20 and viewed from the rotation axis direction of the rotor 14, the fifth non-contacting surface 86b and the seating surface 23 form a fifth. The angle θ5 is larger than the first angle θ1. However, when viewed from the direction of the rotation axis with the seating surface 81a in contact with the seating surface 23, the tangent line at the end of the first non-contacting surface 86b is inclined toward the contacting surface 86a with respect to the seating surface 23. ing. Therefore, the effect of reducing the force received by the cap from the lubricating oil can be obtained, and the effect of reducing the driving torque of the vane pump 10 can be obtained.

In the present embodiment, when the seating surface 81a is in contact with the seating surface 23 and viewed from the rotation axis direction of the rotor 14, the sixth angle θ6 formed by the second non-contacting surface 86c and the seating surface 23 is , Larger than the third angle θ3. In the present embodiment, since the cap has a shape symmetrical with respect to its central axis, the sixth angle θ6 and the fifth angle θ have the same value. Further, when viewed from the rotation axis direction with the seating surface 81a in contact with the seating surface 23, the tangent line at the end of the second non-contacting surface 86c opposite to the rotating direction is in contact with the seating surface 23. It is inclined toward the contact surface 86a.

<Other Embodiments>
Each of the above embodiments may be modified as follows.

-In the first and second embodiments, the fourth angle θ4 may be set to a value of the third angle θ3 or more, provided that the second non-contact surface 46c does not protrude from the second virtual straight line L2. ..

-In the first embodiment, the first angle θ1 and the third angle θ3 may be different, and the second angle θ2 and the fourth angle θ4 may be different. The same applies to the second to fourth embodiments.

-The number of legs of the cap is not limited to two, and may be one or three, for example.

10 ... vane pump, 11 ... housing, 13 ... pump chamber, 14 ... rotor, 20 ... vane, 40 ... cap, 46a ... contact surface, 46b, 46c ... first and second non-contact surfaces.

Claims (3)

A housing with a pump chamber inside and
A vane arranged in the pump chamber and partitioning the pump chamber into a plurality of spaces,
The rotor that rotates the vane and
Seating surfaces provided at both ends of the vane in the longitudinal direction,
A cap provided on each of the seat surfaces is provided.
When viewed from the direction of the rotation axis of the rotor, a predetermined region on the tip end side of the cap, which is a portion of the cap facing the inner wall surface of the housing, becomes the inner wall surface as the rotor rotates. It is a contact surface that comes into contact, and is a non-contact surface that does not contact the other area with the inner wall surface.
When viewed from the rotation axis direction of the rotor, the tangent line at the end of the non-contact surface on the rotation direction side of the rotor on the rotation direction side is inclined toward the contact surface side with respect to the seat surface. Ori,
When the cap is in contact with the seat surface and viewed from the rotation axis direction of the rotor, the non-contact surface on the rotation direction side comes into contact with the end of the seat surface on the rotation direction side. A portion of the surface that does not protrude from the virtual straight line connecting the end on the rotation direction side and that faces the contact surface from the end on the rotation direction side of the non-contact surface on the rotation direction side. A vane pump in which the angle formed by the seat surface (θ2) is smaller than the angle formed by the virtual straight line and the seat surface (θ1). A housing with a pump chamber inside and
A vane arranged in the pump chamber and partitioning the pump chamber into a plurality of spaces,
The rotor that rotates the vane and
Seating surfaces provided at both ends of the vane in the longitudinal direction,
A cap provided on each of the seat surfaces is provided.
When viewed from the rotation axis direction of the rotor, a predetermined region on the tip end side of the cap, which is a portion of the cap facing the inner wall surface of the housing, is inside the housing as the rotor rotates. A contact surface that abuts on the wall surface, and a non-contact surface that does not abut the other region on the inner wall surface.
When the cap is in contact with the seat surface and viewed from the rotation axis direction of the rotor, the non-contact surface on the rotation direction side of the rotor is the end of the seat surface on the rotation direction side and the rotation direction side. The contact surface does not protrude from the virtual straight line connecting the end on the rotation direction side, and the non-contact surface on the rotation direction side extends from the end on the rotation direction side to the contact surface. A vane pump in which the angle (θ2) formed by the facing portion and the seat surface is smaller than the angle formed by the virtual straight line and the seat surface (θ1). The vane pump according to claim 1 or 2 , wherein the cap has a symmetrical shape with respect to a virtual line extending in the longitudinal direction of the vane when viewed from the rotation axis direction of the rotor.

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