JP2015135057A - vane pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vane pump capable of sufficiently suppressing occurrence of cavitation due to suction of an oil even in a high speed operation.SOLUTION: A vane pump includes: a rotor 11 in which a plurality of slit grooves 12 are radially formed; vanes 21 accommodated in the respective slit grooves 12; a cam ring including a cam face which is disposed on an outer periphery of the rotor 11 and with which tips of the vanes 2 come in slidable-contact; and end partition members disposed on both ends in the axial direction of the rotor 11. A pump chamber is formed in a state of being surrounded by a rotor outer peripheral face 14A, the cam face, wall surfaces of the vanes 21 adjacent to each other, and the end partition members, the pump chamber is provided with a suction port and a discharge port, raised edge portion 16 raised outward along both edges of the slit grooves 12, are extended onto the rotor outer peripheral face 14A forming an inner peripheral face of the pump chamber, and a recessed portion 15A shallow at a front side in the rotating direction of the rotor 11 near the suction port, and deep at a rear side in the rotating direction of the rotor 11, far from the suction port, is formed between two raised edge portions 16 facing the pump chamber.

Description

  The present invention relates to a vane pump suitable for use in an automobile.

Although there are various types of hydraulic pumps, vane pumps are used in a wide range of fields such as automobiles and construction machines because they have a relatively large discharge amount and are relatively inexpensive.
For example, FIG. 9 shows the structure of the main part of a conventional vane pump, FIG. 9 (a) is a perspective view of a half of a rotor containing a vane, and FIG. 9 (b) is a rotor containing a vane. It is a cross-sectional view of the half part.

  As shown in FIG. 9A, a plurality of slit grooves 112 are radially formed in the rotor 111, and vanes 121 are accommodated in the respective slit grooves 112 so as to be able to appear and retract. As shown in FIG. 9B, such a rotor 111 is arranged inside a cam ring 131 having a cam surface 132 formed on the inner periphery, and the tip of each vane 121 protruding outward from the rotor 111 is a cam ring. 131 is in sliding contact with the cam surface 132 on the inner periphery.

  A back pressure hole 113 for applying a biasing force to press the vane 121 against the cam surface 132 of the cam ring 131 is formed at the base of each slit groove 112, and each back pressure hole 113 communicates in an annular shape. Oil is supplied from the oil passage that does not. The oil pressure in the back pressure hole 113 acts on the base of the vane 121 to press the vane 121 against the cam surface 132 of the cam ring 131.

  The rotor 111 and the cam ring 131 are installed in a pump housing (not shown), and a space between the outer peripheral surface 114 of the rotor 111 and the cam surface 132 on the inner periphery of the cam ring 131 is partitioned by the wall surfaces of the adjacent vanes 121 and 121. 141 is formed. Further, both ends of the pump chamber 141 (both sides in the rotation axis direction of the rotor 111) are partitioned by a cover member of the pump housing or an end partition member such as an end plate built in the pump housing.

  A suction port 142 is provided at a location where the volume of the pump chamber 141 is increased by the cam surface 132, and a discharge port 143 is provided at a location where the volume of the pump chamber 141 is reduced by the cam surface 132. In each pump chamber 141, oil is sucked from the suction port 142, and oil is discharged from the discharge port 143. In FIG. 9B, the arrangement locations of the suction port 142 and the discharge port 143 are schematically shown by two-dot chain lines, and the port shape is not specified.

  By the way, the outer peripheral surface 114 of the rotor 111 forming the inner periphery of the pump chamber 141 is formed in a cylindrical surface as shown in FIGS. 9A and 9B. As shown in FIG. 1, there is a structure in which the outer peripheral surface 114 of the rotor 111 is formed with a recess 115 over the entire axial length of the rotor 111 except for the vicinity of the slit groove 112. Such a configuration is described in, for example, Patent Documents 1 and 2. Has been.

  In the technique of Patent Document 1, by forming the recess 115, the oil suction area in the suction port 142 is sufficiently increased without changing the outer diameter of the rotor 111, the inner diameter of the cam ring 131, or the radial depth of the slit groove 112. While ensuring the movement stroke of the vane 121, it is possible to improve the oil suction performance at high speed operation and to suppress the occurrence of cavitation during the oil suction, so that the rotation sound and discharge pulsation of the pump can be reduced. I try to make it smaller.

  The technique of Patent Document 2 is such that the mound portion 116 is formed so as to project both edges of the opening of the slit groove 112 toward the inner peripheral surface of the cam ring 131 rather than providing the recess 115. The radial depth is increased to improve the support rigidity of the vane 121 around the slit groove 112, and the vane 121 is prevented from tilting or falling with respect to the radial axis direction based on the center point of the rotor 111. The vane pump performance is stabilized.

  Further, in Patent Document 2, a rib formed so as to extend in the circumferential direction is provided on the outer peripheral surface 114 of the rotor 111, and by connecting between the two mound portions 116 partitioning the pump chamber 141 by this rib, A configuration is also described in which strength and rigidity around the slit groove 112 in which the vane 121 is accommodated are increased while minimizing the volume reduction of the pump chamber 141.

Japanese Utility Model Publication No. 61-181888 JP 2005-105996 A

Incidentally, as described as a problem in Patent Document 1, the occurrence of cavitation when oil is sucked into the pump chamber becomes a larger problem as the speed of the pump increases. As described above, the cavitation cannot be sufficiently suppressed only by securing the oil suction area and improving the oil suction property.
The present invention has been conceived in view of such problems, and an object of the present invention is to provide a vane pump capable of sufficiently suppressing the occurrence of cavitation due to oil suction even during high-speed operation.

  In order to solve the above-described problems, a vane pump according to the present invention includes a rotor in which a plurality of slit grooves are radially formed in a pump housing, a vane accommodated in the slit grooves so as to be able to appear and retract, and the rotor. A cam ring provided on the inner periphery with a cam surface disposed on the outer periphery of the vane and in contact with the tip of each vane on the inner periphery, and end partition members respectively provided at both axial ends of the rotor, A pump chamber is formed by being surrounded by the cam surface, the wall surface of the adjacent vane, and the end partition member, and includes a suction port for sucking oil into the pump chamber and a discharge port for discharging oil from the pump chamber. In addition, on the outer peripheral surface of the rotor that forms the inner peripheral surface of the pump chamber, a protruding edge portion protruding outward along both edges of the slit groove is extended, and each pump chamber is A recess is formed between the two raised edges facing each other, and the recess is shallow on the side close to the suction port (front side in the rotational direction of the rotor) when oil is sucked into the pump chamber, and when the oil is sucked The side far from the suction port (the rear side in the rotation direction of the rotor) is formed deep.

Preferably, the side of the recess close to the suction port when oil is sucked into the pump chamber is raised to the same height as the raised edge and is formed continuously or substantially continuously with the outer end surface of the raised edge. .
It is preferable that the said recessed part is formed with the smooth concave curved surface.
The suction port is preferably formed in the end section member.

Furthermore, it is preferable that a connecting ridge for connecting the two ridge edges is formed at an axially intermediate portion of the outer peripheral surface of the rotor that forms the inner peripheral surface of the pump chamber.
In this case, it is preferable that the recess is formed shallower on the side far from the suction port and shallower on the side closer to the connection ridge, and deeper as the distance from the connection ridge increases.

  It is also preferable that the suction port is formed through the cam ring so as to open to the cam surface.

According to the vane pump of the present invention, when the pump chamber communicates with the suction port by rotation of the rotor, oil is sucked into the pump chamber from the suction port, and when the pump chamber communicates with the discharge port thereafter, the oil in the pump chamber is discharged from the discharge port. Discharged.
On the outer peripheral surface of the rotor that forms the inner peripheral surface of the pump chamber, protruding ridges protruding outward along both edges of the slit groove are extended, and concave portions are formed between the respective protruding edges. Therefore, the depth of the slit groove is secured, the stroke of the vane movement can be secured and the strength and rigidity around the slit groove can be secured, and furthermore, the oil suction area can be sufficiently secured, It is possible to suppress the occurrence of cavitation during oil suction during high-speed operation of the pump.

  Further, since the recess is formed shallower on the side close to the suction port when oil is sucked into the pump chamber, in other words, on the front side in the rotation direction of the rotor, the oil flows smoothly from the suction port into the pump chamber. Thus, when oil is sucked during high-speed operation of the pump, local pressure drop on the surface of the recess can be suppressed, and cavitation can be suppressed from this surface. Further, since the recess is formed deeper on the side farther from the suction port during oil suction, in other words, on the rear side in the rotational direction of the rotor, the pump capacity can be secured by suppressing the volume reduction of the pump chamber.

  The side close to the suction port when oil is sucked into the pump chamber is raised to the same height as the raised edge, and is formed continuously or substantially continuously with the outer end surface of the raised edge to enter the pump chamber from the suction port. Inflow of the oil becomes smoother, local pressure drop on the surface of the recess can be suppressed when oil is sucked during high-speed operation of the pump, and cavitation can be suppressed.

If the concave portion is formed with a smooth concave curved surface, the oil can flow more smoothly into the pump chamber from the suction port, and the occurrence of cavitation during oil suction during high-speed operation of the pump can be more reliably suppressed. it can.
By forming a connecting ridge that connects the ridge edge at the axially intermediate portion of the outer peripheral surface of the rotor that forms the inner peripheral surface of the pump chamber, the strength and rigidity around the slit groove in which the vane is accommodated can be increased. In addition, since the oil suction area can be secured, it is effective in suppressing the occurrence of cavitation during oil suction during high-speed operation of the pump.

  In this case, on the side far from the suction port of the concave portion, the concave portion is shallowly formed on the side close to the connection raised portion, so that the oil flow in the pump chamber becomes smooth, and the oil is sucked at the time of high speed operation of the pump. This is effective for suppressing the occurrence of cavitation. In addition, by forming the recess deeper as the distance from the connection ridge increases, a decrease in the volume of the pump chamber can be suppressed and a pump capacity can be ensured.

  In particular, in the case where the pump chamber has a connecting ridge, when the intake port is formed through the cam ring so as to open to the cam surface, the oil is reduced by forming a shallow recess near the connection ridge. The pump can smoothly flow into the pump chamber from the suction port in the vicinity of the connecting ridge in the axially intermediate portion of the outer peripheral surface of the rotor, and the occurrence of cavitation during oil suction during high-speed operation of the pump can be suppressed. .

It is a figure which shows the structure of the vane pump concerning 1st Embodiment of this invention, Comprising: (a) is a perspective view which shows the half part of the rotor, (b) is the principal part expansion perspective view. It is a cross-sectional view which shows the structure of the vane pump concerning each embodiment of this invention. It is a longitudinal cross-sectional view which shows the structure of the vane pump concerning each embodiment of this invention, and is AA arrow sectional drawing of FIG. It is a principal part expansion perspective view explaining the effect | action and effect by the vane pump concerning 1st Embodiment of this invention, (a) is shown regarding contrast and (b) is shown regarding 1st Embodiment. It is a figure which shows the structure of the vane pump concerning 2nd Embodiment of this invention, Comprising: (a) is a perspective view which shows the half part of the rotor, (b) is the principal part expansion perspective view. It is a principal part expansion perspective view which shows the structure of the vane pump concerning 3rd Embodiment of this invention. It is a principal part expansion perspective view which shows the modification of the structure of the vane pump concerning 1st, 2nd embodiment of this invention, (a) is a 1st modification, (b) is a 2nd modification, (c ) Shows a third modification, and (d) shows a fourth modification. It is a principal part expansion perspective view which shows the modification of the structure of the vane pump concerning 3rd Embodiment of this invention, Comprising: (a) shows a 1st modification, (b) shows a 2nd modification, respectively. It is a figure which shows the structure of the vane pump concerning background art, Comprising: (a) is a perspective view of the rotor half part, (b) is a cross-sectional view of the half part. It is a figure which shows the structure of another vane pump concerning background art, Comprising: (a) is a perspective view of the rotor half part, (b) is the cross-sectional view of the half part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show the structure of the vane pump according to the first embodiment of the present invention, FIGS. 2 and 5 show the structure of the vane pump according to the second embodiment of the present invention, and FIGS. The structure of the vane pump concerning 3rd Embodiment of this is shown, FIG. 7, FIG. 8 shows the modification of the structure of the vane pump concerning 1st-3rd embodiment. A description will be given based on these drawings. In each embodiment and modification, distinctive constituent elements are distinguished by adding A, B, C... At the end of the reference numerals, but FIG. 2, which is common to each embodiment and each modification. In FIG. 3, these components are shown without distinction (without adding A, B, C... At the end of the reference numerals).

[First Embodiment]
First, the structure of the vane pump according to the first embodiment of the present invention will be described.
As shown in FIGS. 2 and 3, the vane pump is provided with a rotor 11 and a cam ring 31 in the pump housing 2. The rotor 11 is coupled so as to rotate integrally with a rotary shaft 1 provided at the center of the pump housing 2. The rotating shaft 1 is connected to an engine (internal combustion engine) or a motor (electric motor) (not shown) directly or indirectly and is driven to rotate.

A plurality of slit grooves 12 are radially formed in the rotor 11 in a cross-sectional view, and vanes 21 are accommodated in the respective slit grooves 12 so as to be able to appear and disappear.
The cam ring 31 is disposed on the outer periphery of the rotor 11, and a cam surface 32 is formed on the inner periphery of the cam ring 31. The cam surface 32 is formed of a curved surface whose distance changes with respect to the axis (rotation center) of the rotary shaft 1. Yes. The tip of each vane 21 is in sliding contact with the cam surface 32 on the inner periphery of the cam ring 31. In the present embodiment, the cam surface 32 is provided at two locations on the entire circumference with a 180 ° phase change, and a location closest to the rotation center and a location farthest from the rotation center.

  In the present embodiment, back pressure holes 13 are formed at the base ends (ends on the axial center side of the rotating shaft 1) of the slit grooves 12, and the back pressure holes 13 are connected to each other by a communication path 13A. A part of oil (working oil) discharged from a discharge port 43 described later is supplied to each back pressure hole 13 through the communication passage 13A, and each oil pressure (back pressure) supplied to the back pressure hole 13 is changed to each of the back pressure holes 13. The vane 21 in the slit groove 12 is urged toward the outer cam surface 32, and the tip of each vane 21 is in sliding contact with the cam surface 32 by this urging force.

Further, one end (the lower end in FIG. 3) of the rotor 11 in the axial direction is connected to the pump housing 2 by an end plate (end section member) 2A, and the other end in the axial direction of the rotor 11 (the upper end in FIG. 3) is The rotor end block portion (end section member) 2B formed in the pump housing 2 is closed except for the suction port 42 and the discharge port 43, respectively.
Thus, the pump chamber 41 is formed by being surrounded and partitioned by the outer peripheral surface 14 of the rotor 11, the cam surface 32 of the cam ring 31, the wall surface of the adjacent vane 21, the end plate 2 </ b> A, and the rotor end closed portion 2 </ b> B. A suction port 42 for sucking oil into the pump chamber 41 and a discharge port 43 for discharging oil from the pump chamber 41 are provided. The suction port 42 and the discharge port 43 are respectively provided at two locations on the entire circumference with a 180 ° phase change corresponding to the shape of the cam surface 32.

  The suction port 42 is provided at a location where the volume of the pump chamber 31 increases with the rotation of the rotor 11 due to the shape of the cam surface 32, and the discharge port 43 is pumped with the rotation of the rotor 11 due to the shape of the cam surface 32. The chamber 41 is provided at a location where the volume is reduced. In the present embodiment, the suction port 42 and the discharge port 43 are respectively provided at both axial ends of the rotor 11 (upper and lower ends in FIG. 3). In FIG. 2, the arrangement positions of the suction port 42 and the discharge port 43 are schematically shown by a two-dot chain line, and the port shape is not specified.

  The suction port 42 and the discharge port 43 are communicated with each other through communication passages 42a and 43a, respectively, and oil is introduced into the suction port 42 from a tank (not shown) through suction passages 44, 44a and 44b by rotation of the rotor 11. Oil is discharged from the discharge port 43, and the discharged oil is supplied to an oil supply unit (not shown) through the discharge passages 45a and 45b.

  In the present embodiment, a characteristic structure is provided on the outer peripheral surface 14 of the rotor 11 that forms the inner peripheral surface of the pump chamber 41. In other words, as shown in FIG. 1, the outer peripheral surface 14 </ b> A of the rotor 11 is provided with a protruding edge 16 that protrudes outward (circumferentially outward) along both edges of the slit groove 12. A recessed portion 15 </ b> A that is recessed from the two raised edges 16, 16 is formed between the two raised edges 16, 16 facing each other. The concave portion 15A is formed shallow on the side close to the suction port 42 when oil is sucked into the pump chamber 41 (that is, the front side in the rotation direction of the rotor 11), and is far from the suction port 42 when oil is sucked. The side (that is, the rear side in the rotation direction of the rotor 11) is not built up or is deeply formed with a reduced build-up amount, and the built-up surface 17A is formed in a curved surface shape.

  In other words, with respect to the reference outer peripheral surface (cylindrical surface) 14 ′ of the rotor 11 indicated by a two-dot chain line in FIG. 1, the side closer to the suction port 42 when the oil is sucked into the pump chamber 41 (the rotation direction of the rotor 11). The front side, the right side in FIG. 1, is a surface that is substantially smooth and continuous with the outer end surface 16 a of the raised edge 16 on the front side in the rotational direction of the rotor 11. When oil is sucked, it decreases as it goes farther from the suction port 42 (the rear side in the rotation direction of the rotor 11, the left side in FIG. 1). The outer peripheral surface 14 'level).

  In the case of the present embodiment, a raised edge portion is further provided at an axially intermediate portion (here, an intermediate portion equidistant from both axial ends) of the outer peripheral surface 14A of the rotor 11 forming the inner peripheral surface of the pump chamber 41. A connecting ridge 18 extending in the circumferential direction is formed so as to connect 16 and 16, and the connecting ridge is formed on the side farther from the suction port 42 of the outer peripheral surface 14 </ b> A of the rotor 11 (the rear side in the rotational direction of the rotor 11). In the vicinity of the portion 18, it is shallow so as to be continuous with the connection raised portion 18, and is formed so as to become deeper as it is separated from the connection raised portion 18.

  In other words, in the vicinity of the ridge edge 16 on the rear side in the rotational direction of the rotor 11 (left side in FIG. 1), the connection ridge is formed with respect to the reference outer peripheral surface 14 ′ of the rotor 11 indicated by a two-dot chain line in FIG. In the vicinity of 18, the surface is thickened and becomes a surface that is substantially smoothly continuous with the outer end surface 18 a of the connection ridge 18. The amount of this buildup is large in the vicinity of the connection ridge 18 and is separated from the connection ridge 18. Accordingly, the thickness is decreased, and the portion farthest from the connecting raised portion 18 has a build-up of 0 (reference outer peripheral surface 14 'level).

In this way, the surface 17A that is built up that constitutes the outer peripheral surface 14A of the rotor 11 according to the present embodiment is formed with a smooth concave curved surface both in the circumferential direction and in the axial direction.
Note that a reference outer circumferential surface 14 ′ and a later-described reference outer circumferential surface 14 ″ of the rotor 11 are cylindrical surfaces (cylindrical surfaces concentric with the rotation center of the rotor 11) corresponding to the deepest portion of the recess 15.
Since the vane pump according to the first embodiment of the present invention is configured as described above, when the pump chamber 41 communicates with the suction port 42 by the rotation of the rotor 11, suction passages 44, 44a, The oil is sucked into the pump chamber 41 from the suction port 42 through 44b. On the other hand, when the pump chamber 41 thereafter communicates with the discharge port 43, the oil in the pump chamber 41 is discharged from the discharge port 43. The discharged oil is supplied to an oil supply unit (not shown) through the discharge passages 45a and 45b.

  The outer peripheral surface 14A of the rotor 11 that forms the inner peripheral surface of the pump chamber 41 is provided with a protruding edge 16 that protrudes outward along both edges of the slit groove 12, and the protruding edges 16, 16 are extended. Since the recess 15A is formed between the two, the depth of the slit groove 12 is secured, the stroke of the vane 21 to move in and out is secured, and the strength and rigidity around the slit groove 12 can be secured. .

Further, since the recess 15A is formed, a sufficient oil suction area can be secured, so that the saturated vapor pressure is reduced and the occurrence of cavitation is suppressed during oil suction during high-speed operation of the pump. Can do.
Moreover, the recess 15A is shallow on the side close to the suction port 42 when oil is sucked into the pump chamber 41 and deep on the side far from the suction port 42 when oil is sucked, so that the recess 15A enters the pump chamber 41 from the suction port 42. Inflow of the oil becomes smooth, and when the oil is sucked in at high speed operation of the pump, the local pressure drop on the surface of the recess 15A is suppressed, and the occurrence of cavitation can also be suppressed from this surface.

  That is, as shown in FIG. 4A, a concave portion 15A ′ that is recessed from the raised edges 16 and 16 is formed between the raised edges 16 and 16 as a reference outer peripheral surface (cylindrical surface) 14 ′ of the rotor 11. If oil is sucked as shown by white arrows in FIG. 4A, the raised edge 16 on the front side in the rotational direction of the rotor 11 as shown by X in FIG. 4A. And a reference outer peripheral surface (cylindrical surface) 14 'intersect with each other at a corner 14a' where a negative pressure region is generated due to the disturbance of the flow of suction oil, and cavitation is likely to occur during high-speed operation.

  On the other hand, the concave portion 15A according to the present embodiment has a curved wall that is substantially smooth and continuous with the outer end surface 16a of the raised edge portion 16 on the front side in the rotation direction of the rotor 11 by embedding the corner portion 14a '. Since it is formed by the raised surface 17A, the oil sucked as shown by the white arrow in FIG. 4B is sucked into the pump chamber 41 without greatly disturbing the flow, so that a negative pressure region is hardly generated. In addition, the occurrence of cavitation is suppressed even during high-speed operation.

  Further, as shown by x in FIG. 4A, the flow of the suction oil is also disturbed at the corner portion 14b ′ where the connecting raised portion 18 of the rotor 11 and the reference outer peripheral surface (cylindrical surface) 14 ′ intersect. Although cavitation is likely to occur during high-speed operation, in the case of this embodiment, as shown in FIG. 4 (b), it is thickened in the vicinity of the connection raised portion 18 and is substantially smooth with the outer end surface 18 a of the connection raised portion 18. The oil that is sucked in does not greatly disturb the flow in the pump chamber 41 and is unlikely to generate a negative pressure region, and the occurrence of cavitation in this portion is suppressed even during high-speed operation. The

In addition, the amount of build-up is reduced as it goes farther from the suction port 42 when oil is sucked, and the amount of build-up is reduced as the distance from the connection ridge 18 is reduced. And the capacity of the pump is secured.
Although the suction port 42 may be formed through the cam ring 31 so as to open to the cam surface 32, the suction port 42 should be formed shallow in the vicinity of the connection raised portion 18 like the recess 15A according to the present embodiment. Accordingly, as shown by the two-dot chain white arrow in FIG. 4B, the oil is pumped from the suction port (not shown) in the vicinity of the connecting raised portion 18 in the axially intermediate portion of the outer peripheral surface 14 of the rotor 11. As a result, the oil can smoothly flow into 41, and the occurrence of cavitation during oil suction during high-speed operation of the pump can be suppressed.

[Second Embodiment]
Next, the structure of the vane pump concerning 2nd Embodiment of this invention is demonstrated.
The overall configuration of the vane pump is configured as shown in FIGS. 2 and 3 and is the same as that of the first embodiment, so only the differences will be described.
In the present embodiment, as shown in FIG. 5, the outer circumferential surface 14 </ b> B of the rotor 11 is raised outward (circumferentially outward) along both edges of the slit groove 12, as in the first embodiment. A recessed portion 15B that is recessed from the raised edge portions 16 and 16 is formed between the raised edge portions 16 and 16, and the shape of the recessed portion 15B is the same as that of the first embodiment. Is different.

  That is, the recess 15B is formed shallower by being thickened on the side close to the suction port 42 when oil is sucked into the pump chamber 41, and is not thickened on the side farther from the suction port 42 when oil is sucked or the amount of buildup is reduced. The surface 17B, which is deeply formed and built up, is formed into a curved surface, and this curved surface is a smooth concave cylindrical surface, and is connected to the connecting ridge 18 on the side far from the suction port 42 when oil is sucked. There is a step between them.

  That is, with respect to the reference outer circumferential surface (cylindrical surface) 14 ′ of the rotor 11 indicated by a two-dot chain line in FIG. 5, the rotor is laid on the side close to the suction port 42 when oil is sucked into the pump chamber 41. 11 is a surface that is substantially smoothly continuous with the outer end surface 16a of the raised edge portion 16 on the front side in the rotational direction, and this build-up amount is reduced toward the side farther from the suction port 42 during oil suction. 11, in the vicinity of the raised edge 16 on the rear side in the rotational direction, the build-up surface is 0 (reference outer peripheral surface 14 ′ level), but the curved build-up surface 17 B is formed in a uniform cross-sectional shape in the axial direction. .

  Since the vane pump according to the second embodiment of the present invention is configured as described above, the corner portion 14a 'is built up by the recess 15B according to the present embodiment, and the surface 17B is the front in the rotational direction of the rotor 11. Since it is formed in a curved surface that is substantially smoothly continuous with the outer end surface 16a of the raised edge portion 16 on the side, the oil to be sucked [see the white arrow in FIG. 5B] does not greatly disturb the flow. Inhalation into the pump chamber 41 is unlikely to generate a negative pressure region, and cavitation is suppressed even during high-speed operation. Further, since the surface 17B is formed in a uniform cross-sectional shape in the axial direction, there is an advantage of good workability.

[Third Embodiment]
Next, the structure of the vane pump according to the third embodiment of the present invention will be described.
The entire configuration of the vane pump is configured as shown in FIGS. 2 and 3 and is the same as that of the first and second embodiments, so only the differences will be described.
In the present embodiment, as shown in FIG. 6, on the outer peripheral surface 14 </ b> C of the rotor 11, as in the first embodiment, a raised edge that protrudes outward (circumferentially outward) along both edges of the slit groove 12. A recess 16C that is recessed from the raised edges 16 and 16 is formed between the raised edges 16 and 16, and the shape of the recessed part 15C is the first and second embodiments. It is different from the form.

  In other words, the outer peripheral surface 14C of this embodiment is not provided with the connecting ridges 18 that connect the ridges 16 to each other, and the recess 15C is located on the side close to the suction port 42 when oil is sucked into the pump chamber 41. The padding is shallow and formed, and the side far from the suction port 42 during oil inhalation is not padded, or the padding amount is reduced and formed deep, and the padded surface 17C is formed into a curved surface. The surface 17C is a smooth concave cylindrical surface and is formed in a uniform cross-sectional shape in the axial direction.

  That is, with respect to the reference outer peripheral surface (cylindrical surface) 14 ″ of the rotor 11 indicated by a two-dot chain line in FIG. 6, the rotor is laid on the side close to the suction port 42 when oil is sucked into the pump chamber 41. 11 is a surface that is substantially smoothly continuous with the outer end surface 16a of the raised edge portion 16 on the front side in the rotational direction, and this build-up amount is reduced toward the side farther from the suction port 42 during oil suction. 11 near the raised edge 16 on the rear side in the direction of rotation, the thickness is 0 (reference outer peripheral surface 14 ″ level), and the surface 17C is formed in a uniform cross-sectional shape in the axial direction.

  Since the vane pump according to the third embodiment of the present invention is configured as described above, the corner 14a ″ is built up by the recess 15C according to the present embodiment, and the bulge on the front side in the rotational direction of the rotor 11 is increased. Since it is formed by a curved surface 17C that is substantially smoothly continuous with the outer end surface 16a of the edge portion 16, the pumped oil 41 [see the white arrow in FIG. 6] sucked oil without greatly disturbing the flow. It is difficult to generate a negative pressure region by being sucked in, and the occurrence of cavitation is suppressed even during high-speed operation, and the curved surface 17C is formed in a uniform cross-sectional shape in the axial direction, so that workability is improved. There are good benefits.

[Modification]
Next, referring to FIG. 7, a modified example of the structure of the vane pump according to the first and second embodiments of the present invention, in particular, the structure of the outer peripheral surface 14 of the rotor 11 serving as the inner peripheral surface of the pump chamber 41 will be described. .
FIG. 7A shows a modification according to the second embodiment, and the outer peripheral surface 14D of the rotor 11 is on the side close to the suction port 42 and the side close to the connection ridge 18 when oil is sucked into the pump chamber 41. Is meat-filled. When the oil is inhaled, the build-up amount gradually decreases toward the side far from the intake port 42, and when the oil is inhaled, there is no build-up on the side far from the intake port 42, and remains the reference outer peripheral surface (cylindrical surface) 14 '. It has become. Thereby, the recess 15D is formed. Moreover, although the surface 17D on which the build-up is formed is formed in a flat shape, it may be formed in a curved surface shape.

  FIG. 7B shows a modification according to the first embodiment. The outer peripheral surface 14E of the rotor 11 is in a pump chamber 41 with respect to the reference outer peripheral surface (cylindrical surface) 14 ′ of the rotor 11 indicated by a two-dot chain line. When the oil is sucked in, the side close to the suction port 42 and the side close to the connection raised portion 18 are overlaid. When oil is inhaled, the amount of build-up gradually decreases toward the side far from the suction port 42 and the side far from the connection ridge 18, and when the oil is inhaled, the amount of build-up is on the side far from the suction port 42 and far from the connection ridge 18. The reference outer peripheral surface (cylindrical surface) 14 'remains unchanged. Thereby, the recess 15E is formed. Further, the surface 17E on which the overlay is formed is formed in a curved surface shape, but may be formed from a plurality of planes.

  FIG. 7C shows a modified example according to the first embodiment. The outer peripheral surface 14F of the rotor 11 is formed with a raised connecting portion 18F in a curved shape, and the reference of the rotor 11 indicated by a two-dot chain line. With respect to the outer peripheral surface (cylindrical surface) 14 ″, the side close to the suction port 42 and the side close to the connection raised portion 18F when oil is sucked into the pump chamber 41 are filled. The build-up amount gradually decreases toward the side far from the connection ridge 18F and the side far from the connection ridge 18F, and there is no build-up on the side far from the suction port 42 and the side far from the connection ridge 18F during oil inhalation, The reference outer peripheral surface (cylindrical surface) 14 ″ remains. Thereby, the recess 15F is formed. The surface 17F that is overlaid is formed in a curved surface.

  FIG. 7D shows a modified example according to the first embodiment, and the outer peripheral surface 14G of the rotor 11 is formed such that the connecting raised portions 18G are raised in a curved shape, and the reference of the rotor 11 indicated by a two-dot chain line. With respect to the outer peripheral surface (cylindrical surface) 14 ″, the side close to the suction port 42 and the side close to the connecting raised portion 18G are filled when oil is sucked into the pump chamber 41. The suction port 42 is filled when oil is sucked. The build-up amount gradually decreases toward the side far from the connection ridge 18G and the side far from the connection ridge 18G, but there is almost no build-up in the region farthest from the suction port 42 and farthest from the connection ridge 18G during oil suction. As a result, a concave portion 15G is formed, and the overlaid surface 17G is formed in a curved surface shape.

  In the example shown in FIGS. 7C and 7D, the height of the end of the connection raised portions 18F and 18G far from the suction port 42 is lower than the height of the raised edge portion 16. The heights of the end portions of the connection raised portions 18F and 18G may be the same as the height of the raised edge portion 16.

Next, a modification of the structure of the vane pump according to the third embodiment of the present invention, in particular, the structure of the outer peripheral surface 14 of the rotor 11 serving as the inner peripheral surface of the pump chamber 41 will be described with reference to FIG.
In the modification shown in FIG. 8A, the outer peripheral surface 14 </ b> H of the rotor 11 is overlaid on the side close to the suction port 42 when oil is sucked into the pump chamber 41. When the oil is inhaled, the amount of build-up gradually decreases toward the side farther from the suction port 42, and when the oil is inhaled, there is no build-up on the side farthest from the suction port 42. Thereby, the recess 15H is formed. In addition, the surface 17H that is overlaid is formed in a planar shape.

  In the modification shown in FIG. 8B, the outer peripheral surface 14J of the rotor 11 is laid on the side close to the suction port 42 when oil is sucked into the pump chamber 41. There is no build-up from the middle part of the rotor in the rotational direction to the rear, and the reference outer peripheral surface (cylindrical surface) 14 ″ remains. This forms a recess 15J. The built-up surface 17J. Is formed in a planar shape, but may be formed in a curved surface shape.

  Thus, also by the structure of each recessed part 15D-15J shown to FIG.7 (a)-(d), FIG.8 (a), (b), recessed part 15D-15J is provided between the protruding edge parts 16 and 16. FIG. Since it is formed, the depth of the slit groove 12 is secured, the stroke of the vane 21 to move in and out is secured, the strength and rigidity around the slit groove 12 can be secured, and the oil suction Since a sufficient area can be secured, it is possible to reduce the saturated vapor pressure and suppress the occurrence of cavitation during oil suction during high-speed operation of the pump.

If the recess 15 is formed by using a flat surface or a relatively simple cylindrical surface, there is an advantage that the processing becomes easy.
Moreover, the recesses 15D to 15J are shallow on the side close to the suction port 42 when oil is sucked into the pump chamber 41 and deep on the side far from the suction port 42 when oil is sucked. 41 smoothly flows, and when the oil is sucked during high-speed operation of the pump, local pressure drop on the surfaces of the recesses 15D to 15J is suppressed, and cavitation is generated from this surface as well. Can be suppressed.

  Further, in the case of the recesses 15E to 15G, the peripheral edges of the connecting ridges 18, 18F, 18G of the rotor 11 are substantially smoothly continuous, and are sucked at the peripheral edges of the connecting ridges 18, 18F, 18G. The oil does not greatly disturb the flow in the pump chamber 41 and is unlikely to generate a negative pressure region, and the occurrence of cavitation in this portion is suppressed even during high-speed operation.

In addition, when the oil is inhaled, the build-up amount decreases as it goes farther from the suction port 42, and the build-up amount decreases as it moves away from the connecting ridges 18, 18F, 18G. The volume reduction of 41 can be minimized, and the capacity of the pump is also secured.
[Others]
As mentioned above, although embodiment of this invention and its modification were demonstrated, this invention is not limited to this embodiment and its modification, This embodiment or its modification is in the range which does not deviate from the meaning of this invention. The examples can be appropriately modified and implemented.

  That is, the recess 15 formed between the raised edges 16 is formed shallower on the side close to the suction port 42 when oil is sucked into the pump chamber 41, that is, on the front side in the rotational direction of the rotor 11. What is necessary is just to form deeply the side far from the said suction port 42, ie, the rotation direction rear side of the rotor 11, and the shape of the recessed part 15 can apply various.

  As a hydraulic source, it can be widely applied and is suitable for use in fields such as automobiles and construction machinery. In particular, it is suitable for a small pump with high demand for high speed operation.

1 Rotating shaft 2 Pump housing 2A End plate (end section member)
2B Rotor end closed portion (end section member)
DESCRIPTION OF SYMBOLS 11 Rotor 12 Slit groove 13 Back pressure hole 13A Communication path 14, 14A-14J Outer peripheral surface of rotor 11 14 ', 14 "Reference outer peripheral surface (cylindrical surface) of rotor 11
15, 15A to 15J Concave portion 16 Raised edge portion 16a Outer end surface of raised edge portion 16, 17A to 17J Overlaid surface 18, 18F, 18G Connection raised portion 18a Outer end surface of connection raised portion 18 21 Vane 31 Cam ring 32 Cam Surface 41 Pump chamber 42 Suction port 43 Discharge port 44, 44a, 44b Suction passage 45a, 45b Discharge passage

Claims (6)

A rotor in which a plurality of slit grooves are radially formed in the pump housing, a vane accommodated in the slit grooves so as to be able to protrude and retract, and a cam surface which is disposed on the outer periphery of the rotor and is in sliding contact with the tips of the vanes. A cam ring provided on the inner periphery, and end partition members respectively provided at both axial ends of the rotor, and the outer peripheral surface of the rotor, the cam surface, the wall surface of the adjacent vane, and the end portion A pump chamber is formed surrounded by the partition member, and includes a suction port for sucking oil into the pump chamber and a discharge port for discharging oil from the pump chamber;
On the outer peripheral surface of the rotor that forms the inner peripheral surface of the pump chamber, protruding ridges protruding outward along both edges of the slit groove are extended, and two raised edges facing the pump chambers A recess is formed between the parts,
The vane pump according to claim 1, wherein the concave portion is shallow on a side close to the suction port when oil is sucked into the pump chamber and deep on a side far from the suction port when oil is sucked. The side close to the suction port when oil is sucked into the pump chamber is raised to the same height as the raised edge, and is formed continuously or substantially continuously with the outer end surface of the raised edge. The vane pump according to claim 1. The vane pump according to claim 1 or 2, wherein the concave portion is formed of a smooth concave curved surface. The vane pump according to any one of claims 1 to 3, wherein the suction port is formed in the end section member. In the axially intermediate portion of the outer peripheral surface of the rotor that forms the inner peripheral surface of the pump chamber, a connecting ridge that connects the two ridges is formed.
5. The concave portion according to any one of claims 1 to 4, wherein the concave portion is formed shallower on the side farther from the suction port and shallower on the side closer to the connection ridge, and becomes deeper as the distance from the connection ridge increases. The vane pump according to item 1. The vane pump according to any one of claims 1 to 5, wherein the suction port is formed so as to penetrate the cam ring so as to open to the cam surface.

Images