JP6670119B2 - Vane pump - Google Patents

Description

  The present invention relates to a vane pump.

  Patent Literature 1 describes a vane pump in which a cutout portion is formed on a side surface of a cam ring that comes into contact with a side plate and that faces a suction recess formed in the side plate. In the vane pump described in Patent Literature 1, a suction port is formed by the suction recess and the notch.

JP-A-2006-125210

  In the vane pump described in Patent Literature 1, hydraulic oil is sucked into a pump chamber defined between vanes through a suction port from a passage formed between an outer periphery of a cam ring and an inner periphery of a body bore with rotation of a rotor. . However, in the vane pump described in Patent Literature 1, since the flow path of the hydraulic oil flowing from the suction port into the pump chamber is bent, a pressure loss is likely to occur when the hydraulic oil is sucked. For this reason, when the vane pump rotates at a high speed, the suction of the hydraulic oil may be insufficient.

  The present invention has been made in view of the above problems, and has as its object to improve the suction efficiency of a working fluid in a vane pump.

  According to a first aspect of the present invention, there is provided an inner peripheral cam surface on which a rotor driven to rotate, a plurality of vanes provided on the rotor so as to be reciprocally movable in a radial direction of the rotor, and the tips of the plurality of vanes slidingly contact as the rotor rotates. A cam ring having a first side member and a second side member disposed so as to sandwich the rotor and the cam ring, and a pump chamber partitioned by the rotor, the cam ring, the adjacent vane, the first side member and the second side member, A suction port that guides the working fluid to the pump chamber; and an annular recess formed on the outer peripheral surface of the rotor, wherein the recesses are inclined so that both sides approach each other toward the bottom surface. Features.

  According to the first aspect, even if the working fluid sucked from the suction port flows into the pump chamber from a direction substantially orthogonal to the outer peripheral surface of the rotor, both side surfaces of the concave portion formed on the outer peripheral surface of the rotor are not affected. Since the working fluid is inclined so as to approach each other toward the bottom surface, the sucked working fluid is smoothly guided toward the axial center of the pump chamber by both side surfaces of the concave portion.

  According to a second aspect of the present invention, the suction port is formed on at least one of an end surface of the cam ring in contact with the first side member and an end surface of the cam ring in contact with the second side member and communicates with the inner and outer peripheral surfaces of the cam ring. The side face on the end face side of the rotor is formed at a position facing the notch.

  In the second aspect, the working fluid sucked from the notch is smoothly guided into the pump chamber by the side surface of the concave portion on the end face side of the rotor. Thereby, the suction efficiency of the pump is improved.

  A third invention is characterized in that the bottom surface of the concave portion is formed by a concave curved surface.

  In the third aspect, since the bottom surface of the concave portion is formed by the concave curved surface, the working fluid can be more smoothly guided into the pump chamber. Thereby, the suction efficiency of the pump is further improved.

  A fourth aspect of the present invention is characterized in that it comprises two concave portions and an annular raised portion formed between the two concave portions and projecting radially from the outer peripheral surface of the rotor.

  According to the fourth aspect, by providing the rotor with the raised portion on the outer peripheral surface, the dead volume of the pump chamber can be reduced.

  According to the present invention, the suction efficiency of the working fluid in the vane pump is improved.

It is sectional drawing of the vane pump which concerns on embodiment of this invention. It is a front view of a rotor, a vane, and a cam ring concerning an embodiment of the present invention, and shows a state where a rotor, a vane, and a cam ring are assembled. It is a perspective view of a rotor concerning an embodiment of the present invention. It is a side view of a rotor concerning an embodiment of the present invention. FIG. 3 is an enlarged cross-sectional view near a pump chamber according to the embodiment of the present invention. It is a front view of the 1st side plate concerning an embodiment of the present invention. FIG. 4 is a side view of the cam ring, the first side plate, and the second side plate according to the embodiment of the present invention, showing a state where the first side plate and the second side plate are assembled to the cam ring. FIG. 3 is a rear view of the cam ring according to the embodiment of the present invention. It is a front view of the 2nd side plate concerning the embodiment of the present invention. It is a figure showing a modification to an embodiment of the present invention.

  Hereinafter, a vane pump 100 according to an embodiment of the present invention will be described with reference to the drawings. The vane pump 100 is used as a hydraulic supply source for a hydraulic device 1 (for example, a power steering device or a transmission) mounted on a vehicle. Here, a description will be given of the vane pump 100 in which a working oil is used as a working fluid, but another fluid such as working water may be used as the working fluid.

  As shown in FIG. 1, the vane pump 100 includes a drive shaft 10, a rotor 20 connected to the drive shaft 10, a plurality of vanes 30 provided on the rotor 20, a cam ring 40 accommodating the rotor 20 and the vane 30, Is provided.

  The drive shaft 10 is rotatably supported by the pump body 50 and the pump cover 60. When power of an engine or an electric motor (not shown) is transmitted to the drive shaft 10, the rotor 20 rotates with the rotation of the drive shaft 10.

  Hereinafter, the direction along the rotation center axis of the rotor 20 is also referred to as “axial direction”, the radial direction of the rotor 20 is also simply referred to as “radial direction”, and the direction in which the rotor 20 rotates during normal operation of the vane pump 100 is simply referred to as “rotation”. Direction ".

  In addition, the vane pump 100 further includes first and second side plates 70 and 80 as first and second side members disposed so as to sandwich the rotor 20 and the cam ring 40 in the axial direction. The first and second side plates 70 and 80 have side surfaces 70a and 80a that contact the rotor 20 and the cam ring 40, respectively. The pump chamber 41 is defined by the rotor 20, the cam ring 40, the adjacent vanes 30, the first side plate 70, and the second side plate 80.

  Next, the shape of the rotor 20 will be described. FIG. 2 is a front view of the rotor 20, the vane 30, and the cam ring 40 as viewed from the pump cover 60 side. FIG. 3 is a perspective view of the rotor 20. FIG. 4 is a side view of the rotor 20. FIG. 5 is an enlarged cross-sectional view near the pump chamber 41.

  As shown in FIGS. 2 to 4, a plurality of slits 22 having openings 21 in an outer peripheral surface 20 a are radially formed at predetermined intervals in the rotor 20.

  As shown in FIGS. 3 to 5, the rotor 20 includes two annular concave portions 23 and 24 formed on the outer peripheral surface 20 a and a radial direction from the outer peripheral surface 20 a of the rotor 20 formed between the concave portions 23 and 24. And an annular raised portion 25 protruding from

  The concave portion 23 has a side surface 23A on the end surface 20b side facing the first side plate 70 of the rotor 20, a side surface 23B on the raised portion 25 side, and a bottom surface 23C formed by a concave curved surface between the side surfaces 23A and 23B. And. The concave portion 23 is formed to be inclined so that the side surface 23A and the side surface 23B approach each other as approaching the bottom surface 23C. The bottom surface 23C is formed by a concave curved surface that is continuous with the side surfaces 23A and 23B.

  The concave portion 24 has a side surface 24A on the end surface 20c side facing the second side plate 80 of the rotor 20, a side surface 24B on the raised portion 25 side, and a bottom surface 24C formed by a concave curved surface between the side surfaces 24A and 24B. And. The concave portion 24 is formed to be inclined so that the side surface 24A and the side surface 24B approach each other as approaching the bottom surface 24C. The bottom surface 24C is formed by a concave curved surface that is continuous with the side surfaces 24A and 24B.

  As shown in FIG. 5, a side surface 23A of the concave portion 23 and a side surface 24A of the concave portion 24 are provided at positions facing notches 43 and 44 formed in a cam ring 40 described later.

  FIG. 2 is referred to again. The vane 30 is slidably inserted into each slit 22. The tip 31 of the vane 30 faces the inner peripheral surface 40 a of the cam ring 40. The base end 32 of the vane 30 is located in the slit 22, and the slit 22 and the vane 30 form a back pressure chamber 26 on the base end 32 side of the vane 30.

  When the rotor 20 rotates, a centrifugal force acts on the vane 30. Due to this centrifugal force, the vane 30 is pushed out in a direction protruding from the slit 22, and the distal end 31 of the vane 30 is pressed against the inner peripheral surface 40 a of the cam ring 40.

  The inner peripheral surface 40a of the cam ring 40 is formed in a substantially elliptical shape. Hereinafter, the inner peripheral surface 40a is also referred to as an “inner peripheral cam surface 40a”.

  Since the inner peripheral cam surface 40 a of the cam ring 40 is formed in a substantially elliptical shape, the vane 30 reciprocates in the radial direction with respect to the rotor 20 as the rotor 20 rotates. As the vane 30 reciprocates, the pump chamber 41 repeats expansion and contraction.

  In this embodiment, while the rotor 20 makes one rotation, the vane 30 reciprocates twice, and the pump chamber 41 repeats expansion and contraction twice. That is, the vane pump 100 has two expansion regions 42a and 42c in which the pump chamber 41 expands and two contraction regions 42b and 42d in which the pump chamber 41 contracts alternately in the rotation direction.

  FIG. 1 is referred to again. The pump body 50 has a housing recess 51 for housing the rotor 20, the cam ring 40, and the first side plate 70. The first side plate 70 is disposed on the bottom surface 51 a of the accommodation recess 51.

  An annular groove 52 is formed on the bottom surface 51 a of the accommodation recess 51. The annular groove 52 and the first side plate 70 form a high-pressure chamber 53 into which the hydraulic oil discharged from the pump chamber 41 flows. The hydraulic oil discharged from the pump chamber 41 is supplied to the hydraulic device 1 through the high-pressure chamber 53.

  FIG. 6 is a front view of the first side plate 70 as viewed from the cam ring 40 side. As shown in FIGS. 1 and 6, the first side plate 70 has a through hole 71 formed at the center thereof, penetrating the first side plate 70. The drive shaft 10 is inserted through the through hole 71.

  The first side plate 70 is provided with two discharge ports 72 for guiding hydraulic oil discharged from the pump chamber 41 to the high-pressure chamber 53. The discharge port 72 is provided so as to be located in each of the contraction regions 42b and 42d.

  While the pump chamber 41 (see FIG. 2) passes through the contraction regions 42b and 42d, the pump chamber 41 contracts. With the contraction of the pump chamber 41, the pressure of the hydraulic oil in the pump chamber 41 increases, and the hydraulic oil in the pump chamber 41 is discharged from the discharge port 72. That is, the hydraulic oil in the pump chamber 41 is discharged from the discharge port 72 while the pump chamber 41 passes through the contraction regions 42b and 42d. As described above, since the hydraulic oil is discharged in the contraction regions 42b and 42d, the contraction regions 42b and 42d are also referred to as “discharge regions”.

  The vane 30 is pushed into the slit 22 most when moving from the contracted area 42d to the expanded area 42a and when moving from the contracted area 42b to the expanded area 42c. At this time, the volume of the pump chamber 41 is minimized. The working oil for the minimum capacity of the pump chamber 41 is not discharged from the pump chamber 41 while the pump chamber 41 passes through the contraction regions 42d and 42b, and remains in the pump chamber 41. Thus, the minimum volume of the pump chamber 41 does not function as a pump, and is also called a dead volume.

  In the first side plate 70, two back pressure passages 73 (see FIGS. 1 and 6) for guiding hydraulic oil from the high pressure chamber 53 to the back pressure chamber 26 (see FIGS. 1 and 2) are formed. As shown in FIG. 6, the back pressure passage 73 is formed in an arc shape centered on the through hole 71 so as to be located in the extended regions 42a and 42c. As a result, the working oil is guided from the high pressure chamber 53 to the back pressure chamber 26 passing through the extension areas 42a and 42c. Therefore, the vane 30 passing through the extension areas 42a and 42c (See FIG. 2) and is pressed against the inner peripheral surface 40 a of the cam ring 40.

  As described above, in the present embodiment, the vane 30 is pressed in the direction protruding from the slit 22 not only by the centrifugal force generated by the rotation of the rotor 20 but also by the pressure in the back pressure chamber 26.

  FIG. 1 is referred to again. The inner diameter of the recess 51 of the pump body 50 is larger than the outer diameter of the cam ring 40. A fluid chamber 54 extending from the outer circumference of the second side plate 80 to the outer circumference of the first side plate 70 is formed between the cam ring 40 and the pump body 50.

  The opening of the housing recess 51 is sealed by the pump cover 60. The pump cover 60 is fixed to the pump body 50 by bolts (not shown). The second side plate 80 is disposed between the pump cover 60 and the cam ring 40.

  A low pressure chamber 61 is formed in the pump cover 60. The low pressure chamber 61 is connected to the tank 2 through a low pressure passage. When the vane pump 100 operates, the hydraulic oil in the tank 2 is supplied to the low-pressure chamber 61 through the low-pressure passage. The low-pressure chamber 61 communicates with the fluid chamber 54, and the operating oil in the tank 2 is supplied to the fluid chamber 54 through the low-pressure chamber 61.

  The cam ring 40 and the second side plate 80 are provided with a side port 81 as a suction port for guiding hydraulic oil in the low-pressure chamber 61 to the pump chamber 41. Further, the cam ring 40 and the first side plate 70 are provided with a side port 74 as a suction port for guiding hydraulic oil in the fluid chamber 54 to the pump chamber 41. The side ports 74 and 81 are provided so as to be located in the respective extended areas 42a and 42c.

  While the pump chamber 41 passes through the expansion areas 42a and 42c (see FIG. 2), the pump chamber 41 expands. As the pump chamber 41 expands, the pressure in the pump chamber 41 decreases, and hydraulic oil is sucked into the pump chamber 41 from the side ports 74 and 81. That is, the hydraulic oil is sucked into the pump chamber 41 from the side ports 74 and 81 while the pump chamber 41 passes through the expansion areas 42a and 42c. As described above, since the operating oil is sucked into the pump chamber 41 in the expansion regions 42a and 42c, the expansion regions 42a and 42c are also called “suction regions”.

  FIG. 7 is a side view in which the first side plate 70 and the second side plate 80 are assembled to the cam ring 40 and viewed from the outside in the radial direction. As shown in FIGS. 6 and 7, two recesses 75 are formed on the side surface 70 a of the first side plate 70. The recess 75 opens in the outer peripheral surface 70 b of the first side plate 70.

  FIG. 8 is a rear view of the cam ring 40 as viewed from the first side plate 70 side. As shown in FIGS. 7 and 8, two notches 43 communicating the inner and outer peripheral surfaces of the cam ring 40 are provided on an end surface 40 b of the cam ring 40 that contacts the first side plate 70. The notch 43 is located in the extended regions 42a and 42c and is formed from the outer peripheral surface 40d of the cam ring 40 to the inner peripheral cam surface 40a.

  As shown in FIG. 7, when the first side plate 70 is assembled to the cam ring 40, the recess 75 of the first side plate 70 faces the notch 43 of the cam ring 40. The hydraulic oil in the fluid chamber 54 (see FIG. 1) is guided to the pump chamber 41 through a port formed by the recess 75 and the notch 43. That is, in the present embodiment, the recess 75 of the first side plate 70 and the notch 43 of the cam ring 40 correspond to the side port 74.

  FIG. 9 is a front view of the second side plate 80 as viewed from the pump cover 60 side. As shown in FIGS. 7 and 9, two recesses 82 are provided on the outer peripheral surface 80 b of the second side plate 80. The depression 82 is formed from the side surface 80a of the second side plate 80 to the side surface 80c of the second side plate 80 opposite to the side surface 80a.

  As shown in FIGS. 2 and 7, two cutouts 44 communicating the inner and outer peripheral surfaces of the cam ring 40 are provided on an end surface 40 c of the cam ring 40 that contacts the second side plate 80. The notch 44 is formed from the outer peripheral surface 40d of the cam ring 40 to the inner peripheral cam surface 40a so as to be located in the extended regions 42a and 42c.

  As shown in FIG. 7, when the second side plate 80 is assembled to the cam ring 40, the recess 82 of the second side plate 80 faces the notch 44 of the cam ring 40. The hydraulic oil in the low-pressure chamber 61 (see FIG. 1) is guided to the pump chamber 41 through a port formed by the recess 82 and the notch 44. As described above, in the present embodiment, the recess 82 of the second side plate 80 and the notch 44 of the cam ring 40 correspond to the side port 81.

  Next, the operation of the vane pump 100 will be described.

  When power of an engine or an electric motor (not shown) is transmitted to the drive shaft 10, the rotor 20 rotates with the rotation of the drive shaft 10. As the rotor 20 rotates, the vane 30 reciprocates with respect to the rotor 20, and the pump chamber 41 repeats expansion and contraction.

  The operating oil in the tank 2 is sucked into the pump chamber 41 passing through the expansion areas 42a and 42c through the low-pressure chamber 61 and the side ports 74 and 81 or through the low-pressure chamber 61, the fluid chamber 54, and the side port 74. At this time, the hydraulic oil sucked through the side ports 74 and 81 is supplied to the pump chamber 41 in the axial center side by the concave portions 23 and 24 formed in the outer peripheral surface 20a of the rotor 20, as shown by arrows in FIG. Guided towards. Specifically, as shown by an arrow A in FIG. 5, the flow of the hydraulic oil is formed to be inclined even when the hydraulic oil is sucked from a direction substantially perpendicular to the outer peripheral surface 20a of the rotor 20. The direction of the flow is smoothly changed toward the axial center of the pump chamber 41 by the side surfaces 23A and 24A. Further, the hydraulic oil is guided toward the axial center of the pump chamber 41 by the bottom surfaces 23C and 24C and the side surfaces 23B and 24B of the concave portions 23 and 24. As described above, in the vane pump 100, by providing the concave portions 23 and 24 on the outer peripheral surface 20 a of the rotor 20, the sucked hydraulic oil can be smoothly guided to the axial center side in the pump chamber 41. As a result, the pressure loss at the time of sucking the hydraulic oil is reduced, so that the suction efficiency of the vane pump 100 is improved.

  The pump chamber 41 into which the hydraulic oil has been sucked in this way passes through the contraction regions 42b and 42d as the rotor 20 rotates. At this time, the hydraulic oil in the pump chamber 41 is discharged from the discharge port 72.

  In the vane pump 100, the concave volumes 23 and 24 are formed in the outer peripheral surface 20a of the rotor 20 to increase the dead volume of the pump chamber 41. However, the raised portion 25 that protrudes radially from the outer peripheral surface 20a of the rotor 20 is provided. This suppresses an increase in the dead volume of the pump chamber 41. Here, the dead volume is the volume of the pump chamber 41 during transition from the contraction areas 42b, 42d to the expansion areas 42a, 42c (the pump chamber 41 is closed while moving from the discharge port 72 to the side ports 74, 81). (The volume of the pump chamber 41 when the pump is in operation). The dead volume will be described in detail below.

  When the concave portions 23 and 24 are formed on the outer peripheral surface 20a of the rotor 20, the dead volume of the vane pump 100 increases accordingly. The dead volume contains high-pressure hydraulic oil that was in communication with the discharge port 72. Therefore, when the pump chamber 41 moves from the discharge port 72 to the side ports 74, 81 and communicates with the side ports 74, 81, the high-pressure hydraulic oil in the pump chamber 41 is transferred to the low-pressure side ports 74, 81. Flow in. At this time, the larger the dead volume, the larger the flow rate of the hydraulic oil flowing into the side ports 74, 81. In this way, when the working oil flows from the pump chamber 41 into the side ports 74 and 81, the suction of the working oil into the pump chamber 41 is prevented, and the suction efficiency of the pump decreases. For this reason, in the vane pump 100, by providing the raised portion 25, the increased volume is offset by the concave portions 23 and 24. That is, by providing the raised portion 25 on the outer peripheral surface 20a of the rotor 20, the dead volume of the pump chamber 41 increased by the concave portions 23 and 24 can be reduced.

  In the case where a gap sufficient to provide the raised portion 25 between the outer peripheral surface 20a of the rotor 20 and the inner peripheral surface 40a of the cam ring 40 cannot be secured, the raised portion 25 may not be provided. Further, in the embodiment shown in FIG. 5, the raised portion 25 is formed so as to be continuous with the side surfaces 23B and 24B of the concave portions 23 and 24, but as in the modification shown in FIG. It may be formed so as to be spaced from the recesses 23 and 24.

  Further, in the embodiment shown in FIG. 5, the bottom surfaces 23C and 24C are formed by concave curved surfaces. However, as in the modification shown in FIG. 10, the bottom surfaces 23C and 24C may be flat surfaces. Although not shown, a flat surface or a curved surface may be combined.

  According to the above embodiment, the following effects can be obtained.

  The vane pump 100 includes annular concave portions 23, 24 formed on the outer peripheral surface 20a of the rotor 20, and the concave portions 23, 24 are arranged such that both side surfaces 23A, 23B, 24A, 24B move toward the bottom surfaces 23C, 24C. Inclined toward each other. Therefore, the hydraulic oil sucked from the side ports 74 and 81 is smoothly guided to the axial center side in the pump chamber 41 by the concave portions 23 and 24. Thereby, the suction efficiency of the pump is improved.

  The side surfaces 23A and 24A of the two concave portions 23 and 24 are formed at positions facing the notches 43 and 44, respectively. The side surfaces 23A and 24A of the recesses 23 and 24 are formed with an inclination so that the flow of the hydraulic oil sucked from the notches 43 and 44 can be controlled. As a result, the hydraulic oil sucked from the notches 43 and 44 flows in a direction substantially perpendicular to the outer peripheral surface 20 a of the rotor 20, but is pumped by the inclined side surfaces 23 A and 24 A of the concave portions 23 and 24. It is smoothly guided into the chamber 41 (toward the axial center of the pump chamber 41). Therefore, the pressure loss when sucking the hydraulic oil from the notches 43 and 44 is reduced, so that the suction efficiency of the vane pump 100 can be improved.

  Further, in the vane pump 100, since the bottom surfaces of the concave portions 23 and 24 are formed by concave curved surfaces, the hydraulic oil sucked from the side ports 74 and 81 can be more smoothly guided into the pump chamber 41. Thereby, the suction efficiency of the vane pump 100 is further improved.

  Further, since the vane pump 100 includes the raised portion 25, the dead volume of the pump chamber 41 increased by providing the concave portions 23 and 24 can be reduced.

  The configuration, operation, and effect of the embodiment of the present invention configured as described above will be described together.

  The vane pump 100 includes a rotor 20 that is driven to rotate, a plurality of vanes 30 provided on the rotor 20 so as to be able to reciprocate in the radial direction of the rotor 20, and a tip portion 31 of the plurality of vanes 30 that slides as the rotor 20 rotates. A cam ring 40 having an inner peripheral cam surface 40a in contact therewith; a first side member (a first side plate 70) and a second side member (a second side plate 80) disposed so as to sandwich the rotor 20 and the cam ring 40; , Cam ring 40, adjacent vane 30, pump chamber 41 defined by first side member (first side plate 70) and second side member (second side plate 80), and suction for introducing working fluid to pump chamber 41. Ports (side ports 74, 81), and annular concave portions 23, 24 formed on the outer peripheral surface 20a of the rotor 20. Parts 23 and 24, characterized in that both side surfaces (side surfaces 23A and 23B, side surfaces 24A and 24B) are inclined towards each other brought toward its bottom 23C, 24C.

  According to this configuration, the hydraulic oil flows into the pump chamber 41 from a direction such that the hydraulic oil sucked from the suction ports (side ports 74 and 81) is substantially perpendicular to the outer peripheral surface 20a of the rotor 20. Also, since the both side surfaces (side surfaces 23A and 23B, side surfaces 24A and 24B) of the concave portions 23 and 24 formed on the outer peripheral surface 20a of the rotor 20 are inclined so as to approach each other toward the bottom surfaces 23C and 24C. The sucked hydraulic oil is smoothly guided toward the axial center of the pump chamber 41 by both side surfaces (side surfaces 23A and 23B, side surfaces 24A and 24B) of the concave portions 23 and 24. Therefore, the suction efficiency of the vane pump 100 is improved.

  In the vane pump 100, the suction ports (side ports 74 and 81) are in contact with the end surface 40b of the cam ring 40 that contacts the first side member (the first side plate 70) and the second side member (the second side plate 80) of the cam ring 40. Notches 43 and 44 formed on at least one of the end surfaces 40c and communicating the inner and outer peripheral surfaces of the cam ring 40. The side surfaces 23A and 24A of the recesses 23 and 24 on the end surfaces 20b and 20c side of the rotor 20 are notches 43 and 44. Is formed at a position opposed to.

  According to this configuration, the hydraulic oil sucked from the notches 43 and 44 is smoothly guided into the pump chamber 41 by the side surfaces 23A and 24A of the recesses 23 and 24 on the end surfaces 20b and 20c side of the rotor 20. Thereby, the suction efficiency of the vane pump 100 is improved.

  The vane pump 100 is characterized in that the bottom surfaces 23C and 24C of the concave portions 23 and 24 are formed by concave curved surfaces.

  According to this configuration, since the bottom surfaces 23C and 24C of the concave portions 23 and 24 are formed by concave curved surfaces, hydraulic oil can be more smoothly guided into the pump chamber 41. Thereby, the suction efficiency of the vane pump 100 is further improved.

  In the vane pump 100, the rotor 20 includes two concave portions 23 and 24 and an annular raised portion 25 formed between the two concave portions 23 and 24 and projecting radially from the outer peripheral surface 20a of the rotor 20. It is characterized by.

  According to this configuration, by providing the raised portion 25 on the outer peripheral surface 20a of the rotor 20, the dead volume of the pump chamber 41 can be reduced.

  As described above, the embodiment of the present invention has been described. However, the above embodiment is only a part of the application example of the present invention, and the technical scope of the present invention is not limited to the specific configuration of the above embodiment. Absent.

  In the above embodiment, the concave portions are provided with the two concave portions 23 and 24, but depending on the flow of the hydraulic oil sucked into the pump chamber 41, only one of the concave portions may be provided.

100 vane pump, 10 drive shaft, 20 rotor, 20a outer peripheral surface, 20b end surface, 20c end surface, 22 slit, 23, 24 ... Recess, 23A, 24A side, 23B, 24B side, 23C, 24C bottom, 25 ridge, 26 back pressure chamber, 30 vane, 40 ...・ Cam ring, 40a ・ ・ ・ Inner peripheral surface (inner peripheral cam surface), 40b ・ ・ ・ End surface, 40c ・ ・ ・ End surface, 40d ・ ・ ・ Outer peripheral surface, 41 ・ ・ ・ Pump chamber, 43, 44 ・ ・ ・ Cut Chipping, 50: Pump body, 60: Pump cover, 70: First side plate (first side member), 72: Discharge port, 74: Side port (suction port), 80 ... Second side plate (second side member), 81 Side port (suction port)

Claims (4)

A rotationally driven rotor,
A plurality of vanes provided on the rotor so as to be able to reciprocate in the radial direction of the rotor,
A cam ring having an inner peripheral cam surface with which the tips of the plurality of vanes slide in contact with the rotation of the rotor,
A first side member and a second side member that are disposed with the rotor and the cam ring interposed therebetween;
A pump chamber partitioned by the rotor, the cam ring, the adjacent vanes, the first side member and the second side member,
A suction port for guiding a working fluid to the pump chamber;
An annular concave portion formed on the outer peripheral surface of the rotor,
The vane pump, wherein the concave portions are inclined so that both side surfaces approach each other as approaching a bottom surface. The suction port is a notch formed in at least one of an end surface of the cam ring in contact with the first side member and an end surface of the cam ring in contact with the second side member, and communicating the inner and outer peripheral surfaces of the cam ring,
2. The vane pump according to claim 1, wherein a side surface of the recess on the end face side of the rotor is formed at a position facing the notch. 3.   The vane pump according to claim 1, wherein a bottom surface of the concave portion is formed by a concave curved surface.   4. The rotor according to claim 1, wherein the rotor includes two recesses and an annular ridge formed between the two recesses and protruding radially from an outer peripheral surface of the rotor. 5. A vane pump according to any one of the preceding claims.

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