WO2020189008A1

WO2020189008A1 - Oil pump

Info

Publication number: WO2020189008A1
Application number: PCT/JP2020/002446
Authority: WO
Inventors: 英俊楊; 浩二佐賀
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2019-03-20
Filing date: 2020-01-24
Publication date: 2020-09-24
Also published as: JP2020153290A

Abstract

A discharge passage that leads from a pump discharge hole to a discharge port connected to an internal combustion engine is formed in a first housing and a second housing accommodating a pump constituent body. The discharge passage is provided with: a first passage that extends in a first direction, which is the direction running along the rotational axis of the pump constituent body, to communicate with the pump discharge hole, that extends in a second direction orthogonal to the first direction, and that is formed larger than the passage area of the pump discharge hole; and an enlarged passage that communicates with the first passage, that extends in the second direction, and that increases in passage area from the first passage towards a discharge port.

Description

Oil pump

The present invention relates to, for example, an oil pump.

For example, as an oil pump applied to an internal combustion engine for an automobile, the one described in Patent Document 1 below is known.

According to the technique described in Patent Document 1, oil discharged from a pump component provided inside the housing of an oil pump is supplied to an internal combustion engine from a discharge hole through a passage provided inside the housing.

Japanese Unexamined Patent Publication No. 2016-104967

However, in the technique described in Patent Document 1, since the passage area through which the oil discharged from the pump component flows and the passage area provided inside the housing is substantially constant, the flow path resistance is large. , There was a risk that the flow rate of oil required for the internal combustion engine could not be supplied sufficiently.

An object of the present invention has been devised in view of such technical problems, and an object of the present invention is to provide an oil pump capable of reducing the flow path resistance and supplying the flow rate of oil required for an internal combustion engine.

According to the present invention, in one aspect thereof, a discharge passage is formed between a pump discharge hole of a pump structure and a discharge port connected to an internal combustion engine, and the discharge port is formed in the discharge passage. It is configured to have an enlarged passage where the passage area becomes larger as it gets closer.

According to one embodiment of the present invention, it is possible to provide an oil pump capable of reducing the flow path resistance and supplying the flow rate of oil required for the internal combustion engine.

It is an exploded perspective view which shows each component part of the oil pump which concerns on embodiment of this invention. It is external perspective view of the oil pump which concerns on embodiment of this invention. It is a perspective view which looked at the oil pump which concerns on embodiment of this invention from the 2nd housing side. It is a perspective view which looked at the oil pump which concerns on embodiment of this invention from the 1st housing side. It is a hydraulic circuit diagram of the variable capacity type oil pump which concerns on embodiment of this invention. It is an enlarged view of the variable capacity type oil pump shown in FIG. It is an enlarged view of the pilot valve shown in FIG. It is an enlarged view of the solenoid valve shown in FIG. It is an external perspective view which shows the state which attached the oil pump which concerns on embodiment of this invention to an oil pan. It is a top view which shows the state which attached the oil pump which concerns on embodiment of this invention to an oil pan. FIG. 5 is a sectional view taken along line XI-XI shown in FIG. It is a perspective view which a part of the oil pump was broken.

Hereinafter, examples of the oil pump according to the present invention will be described with reference to the attached drawings. The present invention is not limited to the following examples, and various modifications and applications are included in the technical concept of the present invention.

The oil pump in this embodiment is applied to a variable displacement vane pump, and is provided at the front end of a cylinder block of an internal combustion engine. FIG. 1 is an exploded perspective view showing each component of the oil pump according to the embodiment of the present invention, FIG. 2 is an external perspective view of the oil pump according to the embodiment of the present invention, and FIG. 3 is an oil according to the embodiment of the present invention. A perspective view of the pump as viewed from the second housing side, FIG. 4 is a perspective view of the oil pump according to the embodiment of the present invention as viewed from the first housing side.

The oil pump 1 has a pump accommodating portion 2s formed inside, and has an outer shell formed by a bottomed cylindrical first housing 2 having an opening at one end and a second housing 3 that closes the opening of the first housing 2. It is formed.

The first housing 2 is rotatably housed inside the first housing 2 and a drive shaft 4 which is rotationally driven by a crankshaft of an engine (not shown) so as to penetrate substantially the center of the second housing 3. A rotor 5 whose central portion is coupled to a drive shaft 4 and a control ring 6 which is a movable member oscillatingly arranged on the outer peripheral side of the rotor 5 are provided.

The second housing 3 is provided with a pilot valve 7 which is a control mechanism for controlling hydraulic pressure supply switching in order to swing the control ring 6.

The pilot valve 7 is housed in a cylindrical valve body 3a formed in the second housing 3. The pilot valve 7 is mounted between the spool valve body 7a that can slide in the valve body 3a in the vertical direction, the plug 7c that closes the upper end opening of the valve body 3a, and the spool valve body 7a and the plug 7c. It is provided with a valve spring 7b that urges the spool valve body 7a downward.

The first housing 2 and the second housing 3 are integrally connected by a plurality of screws 8, and each of the screws 8 is inserted into the screw insertion holes formed in the first housing 2 and the second housing 3, respectively. And these are to be concluded.

The first housing 2 is integrally formed of an aluminum alloy material, and one side surface of the control ring 6 in the axial direction slides on the bottom surface of the concave pump accommodating portion 2s, so that accuracy such as flatness and surface roughness can be improved. It is machined high and the sliding range is formed by machining. In this embodiment, the first housing 2 and the second housing 3 form a housing to be a housing of the variable displacement pump, and the pump accommodating portion 2s is formed inside the housing.

Further, in the first housing 2, a bearing hole (not shown) for bearing one end of the drive shaft 4 is formed through the bottom surface of the pump accommodating portion 2s, which is an operating chamber, at a substantially central position, and the inner peripheral surface thereof. At a predetermined position, a bottomed pin hole (not shown) into which a pivot pin 9 which is a pivot pin serving as a pivot point of the control ring 6 is inserted is bored.

Further, a first seal sliding contact surface 2a, a second seal sliding contact surface 2b, and a third seal sliding contact surface 2c are formed on the inner peripheral side of the pump accommodating portion 2s.

The first seal sliding contact surface 2a, the second seal sliding contact surface 2b, and the third seal sliding contact surface 2c are each provided with a first seal member 10a, a second seal member 10b, and a third seal provided on the control ring 6. Each of the members 10c is always in sliding contact to seal.

The drive shaft 4 protrudes from the first housing 2, and a sprocket 11 is inserted into the protruding tip and fixed with a nut 12. The rotational force transmitted from the crankshaft is transmitted to the rotor 5 via the sprocket 11 to rotate the rotor 5.

In the rotor 5, seven vanes 13 are slidably held in the seven slits 5a formed radially from the inner center side to the outside so that the vanes 13 can move forward and backward (can appear and disappear). The vane 13 pushes the vane 13 outward by the centrifugal force accompanying the rotation of the rotor 5.

In each vane 13, each base end edge on the inside is in sliding contact with the outer peripheral surfaces of the pair of front and

rear vane rings

14, 14, and each tip edge is in sliding contact with the inner peripheral surface 6d of the control ring 6. Further, a pump chamber (a plurality of oil chambers) is provided between the adjacent vanes 13 and the inner peripheral surface 6d of the control ring 6 and the inner peripheral surface of the rotor 5, the pump accommodating portion 2s, and the inner surface of the first housing 2. (Not shown) are liquidtightly separated. Each vane ring 14 is designed to push each vane 13 out of radiation as it rotates, and even when the engine speed is low and the centrifugal force is small, each tip of each vane 13 is controlled. The pump chamber is liquid-tightly separated by sliding contact with the inner peripheral surface of the ring 6.

The control ring 6 is integrally formed of a sintered metal that is easy to process into a substantially cylindrical shape, and as shown in FIG. 1, a pivot recess 6e is formed at a position of a pivot pin 9 on the outer peripheral surface, and the pivot recess 6e is formed. The pivot pin 9 inserted and positioned in is inserted and inserted to serve as an eccentric swing fulcrum. The control ring 6 is provided with an arm portion 19 that receives a coil spring 18 that urges the control ring 6 in the eccentric direction. The coil spring 18 is housed in a spring accommodating chamber 2d formed in the first housing 2.

Further, a first seal holding groove 6a and a first seal holding groove 6a for inserting the first seal member 10a, the second seal member 10b, and the third seal member 10c into the outer peripheral surface of the control ring 6 on the lower side of the pivot recess 6e. The 2 seal holding groove 6b and the 3rd seal holding groove 6c are formed.

The three seal members 10 (first seal member 10a, second seal member 10b, third seal member 10c) are elongated linearly along the axial direction of the control ring 6 by, for example, a fluororesin material having low friction characteristics. The first seal is slidably contacted by the elastic force of a rubber elastic member formed at the bottom of each seal holding groove (first seal holding groove 6a, second seal holding groove 6b, third seal holding groove 6c). It is pressed against the surface 2a, the second seal sliding contact surface 2b, and the third seal sliding contact surface 2c. As a result, good liquidtightness of the three control oil chambers is always ensured. The pressure of the three control oil chambers changes by swinging around the pivot pin 9. The specific configuration of the control oil chamber will be omitted.

Further, the first housing 2 is provided with a check valve 17 that returns the oil to the oil pan when the pump discharge pressure rises excessively. The check valve 17 is composed of a check ball 17a that opens and closes the flow path, a check spring 17b that gives an urging force to the check ball 17a, and a plug 17c that prevents the check spring 17b from coming off.

In this embodiment, the pump component is formed by the drive shaft 4, the rotor 5, the control ring 6, the vane 13, and the vane ring 14. The pump structure is housed inside the pump accommodating portion 2s, and the oil guided from the suction port 15 by being rotationally driven is discharged from the discharge port 16 formed in the second housing 3.

In the oil pump 1, a flow path from the suction port 15 to the discharge port 16 is formed inside the oil pump 1 in a state where the first housing 2 and the second housing 3 are combined.

Next, the configuration of the oil pump 1 will be described with reference to FIG. The oil pump 1 of this embodiment has a variable capacity type.

The oil pump 1 can be rotated into a housing including a first housing 2 having an opening on one end side and a pump accommodating portion 2s provided inside, and a second housing 3 for closing one end opening of the first housing 2. The drive shaft 4 is supported by the pump and is rotationally driven by the crankshaft 21 (FIG. 9) through the substantially central portion of the pump accommodating portion 2s, and is movable (swinging) accommodating in the pump accommodating portion 2s. A control ring 6 which is a member and constitutes a variable mechanism for changing the volume change amount of the pump chamber PR described later in cooperation with the first control oil chamber 31, the second control oil chamber 32 and the like described later and the coil spring 18. The volume of the plurality of pump chambers PR formed between the control ring 6 and the control ring 6 is increased or decreased by being housed on the inner peripheral side of the control ring 6 and rotationally driven by the drive shaft 4 in the clockwise direction in FIG. A pump structure that pumps the pump, and a control mechanism that is provided on the downstream side of the oil main gallery MG of the internal combustion engine and controls the supply and discharge of hydraulic pressure to the first control oil chamber 31 and the second control oil chamber 32, which will be described later. The pilot valve 7 is provided in the oil passage (first introduction passage 72 described later) branched from the oil main gallery MG, and the introduction of the control pressure guided from the oil main gallery MG to the pilot valve 7 is switched. It includes a solenoid valve 60, which is a switching mechanism for controlling.

Here, the pump configuration is rotatably housed on the inner peripheral side of the control ring 6, and the central portion thereof is fitted on the outer peripheral surface of the drive shaft 4 and the rotor 5 is radially cut out on the outer peripheral portion of the rotor 5. A plurality of vanes 13 which are housed in the formed slits 5a so as to be able to appear and disappear, and a pair of vane rings 14 which are formed to have a diameter smaller than that of the rotor 5 and are arranged on both inner peripheral side portions of the rotor 5. , Consists of.

The first housing 2 is integrally formed of an aluminum alloy material, and a bearing hole 2e that rotatably supports one end of the drive shaft 4 is formed through the end wall of the pump accommodating portion 2s at a substantially central position. ing. Then, the outer peripheral region of the bearing hole 2e is substantially arcuately concave so as to open in a region where the volume of each pump chamber PR expands (hereinafter, referred to as “suction region”) due to the pumping action of the pump structure. The suction port 23a, which is the suction portion of the pump chamber, is opened in a region where the volume of each pump chamber PR is reduced (hereinafter, referred to as “discharge region”), and the discharge port 24a, which is a substantially arcuate concave discharge portion, is provided. Notches are formed so as to substantially face each other with the bearing hole 2e in between.

Further, a support groove 2f having a substantially semicircular cross section for swingably supporting the control ring 6 is formed at a predetermined position on the inner peripheral wall of the pump accommodating portion 2s via a rod-shaped pivot pin 9. Further, in the inner peripheral wall of the pump accommodating portion 2s, when M is a straight line connecting the center of the bearing hole 2e and the center of the support groove 2f and N is a straight line orthogonal to this straight line M, it is on the left side of the straight line N. A discharge region is formed and a suction region is formed on the right side.

In the range corresponding to the suction region, the first seal sliding contact surface 2a to which the first seal member 10a fitted to the outer peripheral portion of the control ring 6 can always be in sliding contact is controlled in the range corresponding to the discharge region. A third seal sliding contact surface 2c is formed so that the third sealing member 10c fitted to the outer peripheral portion of the ring 6 can always be in sliding contact.

The suction port 23a is integrally provided with an introduction portion 25 formed so as to bulge toward the spring accommodating chamber 2d, which will be described later, at a substantially intermediate position in the circumferential direction, and the introduction portion 25 and the suction port 23a are integrally provided. A pump suction hole 23b that penetrates the end wall of the first housing 2 and opens to the outside is formed in the vicinity of the boundary portion of the first housing 2. With this configuration, the oil stored in the oil pan 20 of the internal combustion engine is connected to the suction region via the pump suction hole 23b and the suction port 23a based on the negative pressure generated by the pumping action of the pump structure. It is designed to be inhaled by PR. Here, the pump suction hole 23b is configured to communicate with the low pressure chamber 35 formed in the outer peripheral region of the control ring 6 in the suction region together with the introduction portion 25, and the low pressure chamber 35 also has the suction pressure. Low pressure oil is guided.

On the other hand, as shown in FIGS. 5 and 6, the discharge port 24a has a notch 26 on the outer peripheral side of the starting end portion thereof, which constitutes a discharge passage connected to the discharge port 24a and the pump discharge hole 27 described later. Has been done. Then, at the outer end of the communication passage 26, the oil is discharged from the pump structure by penetrating the end wall of the first housing 2 and opening to the outside, and is guided to the discharge port 24a via the communication passage 26. A pump discharge hole 27 for discharging the oil to the oil main gallery MG through a filter (not shown) is formed through along the axial direction. The pump discharge hole 27 is provided so as to directly open into the first passage 81 via the communication hole 80, that is, a part thereof overlaps with the communication passage 26.

In the drive shaft 4, one end in the axial direction that penetrates the end wall of the first housing 2 and faces the outside is linked to the crankshaft 21 (FIG. 9), and the rotor 5 is based on the rotational force transmitted from the crankshaft 21. Is rotated clockwise in FIG.

The rotor 5 has a plurality of slits 5a formed radially outward from the center side thereof, and a cross section for introducing discharge oil at the inner base end portion of each slit 5a. A back pressure chamber 5b having a substantially circular shape is provided, and each vane 13 is pushed outward by the centrifugal force accompanying the rotation of the rotor 5 and the pressure in the back pressure chamber 5b.

Each vane 13 has its tip surface in sliding contact with the inner peripheral surface of the control ring 6 and each base end surface in sliding contact with the outer peripheral surface of each vane ring 14 when the rotor 5 is rotated. That is, each of these vanes 13 is configured to be pushed upward in the radial direction of the rotor 5 by each vane ring 14, when the engine speed is low and the centrifugal force and the pressure of the back pressure chamber 5b are small. Even if there is, each tip is in sliding contact with the inner peripheral surface of the control ring 6, and each pump chamber PR is liquid-tightly separated.

The control ring 6 is integrally formed of a so-called fired metal in a substantially cylindrical shape, and at a predetermined position on the outer peripheral portion thereof, a substantially arcuate groove-shaped pivot portion that forms an eccentric swing fulcrum by being fitted with a pivot pin 9. A notch 28 is formed along the axial direction, and a coil spring 18 which is an urging member set to a predetermined spring constant is provided at a position opposite to the pivot portion 28 with the center of the control ring 6 interposed therebetween. The interlocking arm portions 19 are projected along the radial direction. The arm portion 19 is provided with a pressing protrusion 19a formed in a substantially arc-convex shape on one side in the moving (rotating) direction, and the pressing protrusion 19a is the tip of the coil spring 18. The arm portion 19 and the coil spring 18 are linked by constantly contacting the portions.

Further, from such a configuration, inside the first housing 2, a spring accommodating chamber 2d for accommodating and holding the coil spring 18 is provided adjacent to the pump accommodating portion 2s at a position facing the support groove 2f. A coil spring 18 is mounted in the spring accommodating chamber 2d with a predetermined set load W1 between one end wall thereof and the arm portion 19 (pressing protrusion 19a). The other end wall of the spring accommodating chamber 2d is configured as a regulating portion 29 that regulates the movement range of the control ring 6 in the eccentric direction, and is controlled by abutting the other side portion of the arm portion 19 on the regulating portion 29. Further movement of the ring 6 in the eccentric direction is restricted.

In this way, the eccentricity of the control ring 6 increases via the arm portion 19 due to the urging force of the coil spring 18 (clockwise in FIG. 6, hereinafter referred to as "eccentricity". ) Is constantly urged, and in the non-operating state, as shown in FIG. 6, the other side portion of the arm portion 19 is pressed against the regulating portion 29, and the eccentricity is regulated to the maximum position. It is supposed to be done.

Further, the outer peripheral portion of the control ring 6 has a first to third seal configuration having a concentric arcuate sealing surface with the first to third seal sliding contact surfaces 2a to 2c provided on the inner peripheral wall of the pump accommodating portion 2s, respectively. The portions 30a to 30c are formed so as to project, and the first to third seal members 10a to 10c are housed and held on the seal surfaces of the first to third seal constituent portions 30a to 30c, respectively. The first to third seal members 10a to 10c are all formed in a linearly elongated shape along the axial direction of the control ring 6 by, for example, a fluororesin material having low friction characteristics, and are backed up by an elastic member made of rubber. By being pressed against the first to third seal sliding contact surfaces 2a to 2c, between the first to third seal sliding contact surfaces 2a to 2c and the sealing surfaces of the first to third seal constituent parts 30a to 30c. Is liquid-tightly separated.

Then, due to such a seal structure, the outer peripheral portion of the control ring 6 includes the first seal member 10a, the second seal member 10b, and the pivot pin 9 housed and held in the first seal component 30a and the second seal component 30b. The pair of the first control oil chamber 31 and the second control oil chamber 32 are separated by. The first control oil chamber 31 and the second control oil chamber 32 are configured to be guided into the engine through a control pressure introduction passage 70 branched from the oil main gallery MG. Specifically, the first control oil chamber 32 is introduced through one of the bifurcated branch passages from the control pressure introduction passage 70, and the first control oil chamber 31 is introduced by the other branch passage. Control pressure corresponding to the in-engine hydraulic pressure, which is the pump discharge pressure reduced by the passage of an oil filter (not shown) through the passage 72, the solenoid valve 60, the second introduction passage 71, and the pilot valve 7, respectively (hereinafter, simply "control"). Pressure ”) is supplied.

In this way, the control pressure acts on the first pressure receiving surface 6f and the second pressure receiving surface 6g formed on the outer peripheral surfaces of the control ring 6 facing the first control oil chamber 31 and the second control oil chamber 32, respectively. As a result, a moving force (swinging force) with respect to the control ring 6 is applied. Here, the pressure receiving area of the second pressure receiving surface 6g is larger than the pressure receiving area of the first pressure receiving surface 6f, and the pressure receiving area of the first pressure receiving surface 6f and the pressure receiving area of the third pressure receiving surface 6h described later are combined. It is set to be smaller than the pressure receiving area, and when the same hydraulic pressure acts on the

pressure receiving surfaces

6f and 6g, the direction of increasing the eccentricity as a whole (clockwise in FIG. 6; The control ring 6 is urged in the "anti-concentric direction (increase in the amount of eccentricity)").

Further, between the first control oil chamber 31 and the second control oil chamber 32 in the circumferential direction, a third control oil chamber is formed by a third seal member 10c and a pivot pin 9 housed and held in the third seal component 30c. 36 are separated. The third control oil chamber 36 has a third pressure receiving surface 6h, so that the pressure is lower than the pump discharge pressure itself (hereinafter, simply referred to as “pump discharge pressure”) discharged from the pump component. It is connected to the outside and is connected to the atmospheric pressure or low pressure chamber 35. By providing the third control oil chamber 36, it is possible to form the first pressure receiving surface 6f of the first control oil chamber 31 smaller than the second pressure receiving surface 6g of the second control oil chamber 32.

From such a configuration, in the oil pump 1, when the urging force based on the internal pressure of the first control oil chamber 31, the second control oil chamber 32 and the third control oil chamber 36 is small with respect to the set load W1 of the coil spring 18. The control ring 6 is in the maximum eccentric state as shown in FIG. 6, while the internal pressures of the first control oil chamber 31, the second control oil chamber 32, and the third control oil chamber 36 are increased as the pump discharge pressure increases. When the urging force based on the oil exceeds the set load W1 of the coil spring 18, the control ring 6 moves in the concentric direction (hereinafter, concentric direction) which is the opposite direction of the semi-concentric direction according to the discharge pressure.

The pilot valve 7 is connected to the second introduction passage 71 via an introduction port 50 which is an opening on one end side, and a valve body 3a formed in a substantially cylindrical shape in which the opening on the other end side is closed by a plug 7c and a valve body. A pair of large-diameter first land portions 43a and second land portions 43b that are slidably housed on the inner peripheral side of 3a and are in sliding contact with the inner peripheral surface of the valve body 3a are provided with the first control oil chamber 31, the first. 2 The spool valve body 7a used for controlling the supply and discharge of hydraulic pressure to the control oil chamber 32 and the plug 7c and the spool valve body 7a are mounted with a predetermined set load W2 on the inner circumference on the other end side of the valve body 3a. It is mainly composed of a valve spring 7b that constantly urges the spool valve body 7a toward one end side of the valve body 3a.

The valve body 3a accommodates a valve having an inner diameter substantially the same as the outer diameter of the spool valve body 43 (outer diameters of the first land portion 43a and the second land portion 43b) in a range excluding both ends in the axial direction. A portion 41a is bored, and a spool valve body 7a is accommodated and arranged in the valve accommodating portion 41a. An introduction port 50 for introducing control pressure is formed at one end of the valve body 3a in the axial direction by connecting to the second introduction passage 71, while an inner peripheral portion thereof is formed at the other end. The plug 7c is screwed through the female screw portion formed in the above.

Further, on the peripheral wall of the valve accommodating portion 41a, a connection port 51 connected to the supply / discharge port 68 of the solenoid valve 60 is formed at a position on one end side in the axial direction via the second introduction passage 71, and is formed in the axial direction. A supply / discharge port 52 connected to the first control oil chamber 31 is formed at an intermediate position, and the hydraulic pressure of the first control oil chamber 31 and the second control oil chamber 32 guided through the internal passage 55 is discharged. The first drain port 53 and the second drain port 54 to be used for the above are formed as openings.

In the spool valve body 7a, a first land portion 43a and a second land portion 43b are formed at both ends in the axial direction, and the first land portion 43a and the second land portion 43b are connected by a small diameter shaft portion 43c. ing. Then, by accommodating the spool valve body 7a in the valve accommodating portion 41a, the spool valve body 7a is provided between the first land portion 43a and the valve body 3a inside the valve accommodating portion 41a via the introduction port 50. The pressure chamber 56 into which the control pressure is introduced, the relay chamber 57 provided on the outer periphery of the small diameter shaft portion 43c for relaying between the supply / discharge port 52 and the first drain port 53, the second land portion 43b, and the plug 7c. A back pressure chamber 58 provided between the two and used for discharging the hydraulic pressure guided through the internal passage 55 is separated from each other.

From such a configuration, the pilot valve 7 is subjected to the urging force of the valve spring 7b based on the set load W2 when the control pressure guided from the introduction port 50 to the pressure chamber 56 is equal to or less than a predetermined pressure (spool operating hydraulic pressure Ps). The spool valve body 7a is pressed against one end side of the valve body 3a. That is, while the second introduction passage 71 and the relay room 57 are communicated with each other via the connection port 51, the communication between the first drain port 53 and the relay room 57 is blocked by the second land portion 43b, and the communication between the first drain port 53 and the relay room 57 is blocked, and the communication is cut off via the supply / discharge port 52. The first control oil chamber 31 and the relay chamber 57 are communicated with each other. As a result, the hydraulic pressure guided from the second introduction passage 71 through the connection port 51 is supplied to the first control oil chamber 31 via the relay chamber 57 and the supply / discharge port 52.

Then, when the control pressure guided to the pressure chamber 56 exceeds the predetermined pressure, the spool valve body 7a moves to the other end side of the valve body 3a against the urging force of the valve spring 7b, and the supply / discharge port 52 is opened. Communication between the first control oil chamber 31 and the relay chamber 57 is maintained through the passage. On the other hand, when the communication between the second introduction passage 71 and the relay chamber 57 is cut off by the first land portion 43a, the relay chamber 57 and the oil pan 20 are communicated with each other through the first drain port 53 almost at the same time. As a result, the oil in the first control oil chamber 31 is switched so as to be discharged from the first drain port 53 to the oil pan 20 through the supply / discharge port 52 and the relay chamber 57.

The solenoid valve 60 is housed and arranged inside a valve accommodating hole (not shown) interposed in the middle of the first introduction passage 72, and a substantially cylindrical valve body 61 having an oil passage 65 penetrating along the internal axial direction. And, at one end of the valve body 61 (the left end in the figure), the oil passage 65 is expanded and fixed to the outer end of the valve body accommodating portion 66, and the first introduction passage 72 is fixed at the center. A seat member 62 having an introduction port 67 which is an upstream opening connected to the upstream passage 72a of the seat member 62 and a valve seat 62a formed at the inner end opening edge of the seat member 62 so as to be detachable and seatable. It is mainly composed of a ball valve body 63 used for opening and closing the introduction port 67, and a solenoid 64 provided at the other end of the valve body 61 (the right end in the figure).

In the valve body 61, a valve body accommodating portion 66 accommodating the ball valve body 63 is provided on the inner peripheral portion on one end side in a stepped diameter with respect to the oil passage 65, whereby the inner end of the valve body accommodating portion 66 is provided. A valve seat 66a similar to the valve seat 62a provided on the seat member 62 is also formed on the opening edge of the portion. Further, on the outer peripheral portion of the valve body accommodating portion 66, which is one end side in the axial direction of the peripheral wall of the valve body 61, a supply / discharge port 68 connected to the downstream passage 72b and used for supplying / discharging hydraulic pressure to the pilot valve 7 has a diameter. A drain port 69 connected to the oil pan 20 is formed through the outer peripheral portion of the oil passage 65 on the other end side along the radial direction.

The solenoid 64 has an armature (not shown) arranged on the inner peripheral side of the coil and a rod 64b fixed to the armature (not shown) having an electromagnetic force generated by energizing a coil (not shown) housed inside the casing 64a. Is configured to advance and move to the left in FIG. The solenoid 64 is energized with an exciting current from an in-vehicle ECU (not shown) based on an engine operating state detected or calculated by predetermined parameters such as the oil temperature and water temperature of the internal combustion engine and the engine speed. It becomes.
From such a configuration, when the solenoid 64 is energized, the ball valve body 63 arranged at the tip of the rod 64b is pressed against the valve seat 62a on the seat member 62 side by the advance movement of the rod 64b, and the introduction port. The communication between the supply / discharge port 68 and the supply / discharge port 68 is cut off, and the supply / discharge port 68 and the drain port 69 communicate with each other through the oil passage 65. On the other hand, when the solenoid 64 is not energized, the ball valve body 63 moves backward based on the control pressure guided from the introduction port 67, so that the ball valve body 63 is pressed against the valve seat 66a on the valve body 61 side and introduced. The port 67 and the supply / discharge port 68 are in a communication state, and the communication between the supply / discharge port 68 and the drain port 69 is cut off.

Next, the state in which the oil pump 1 is attached to the oil pan will be described with reference to FIGS. 9 and 10. FIG. 9 is an external perspective view showing a state in which the oil pump according to the embodiment of the present invention is attached to the oil pan, and FIG. 10 is a top view showing a state in which the oil pump according to the embodiment of the present invention is attached to the oil pan. ..

The oil pump 1 is housed in the oil pan 20. The oil pan 20 is composed of an oil pan lower 20a having an open upper portion and an oil pan upper 20b placed above the oil pan lower 20a. The oil pan upper 20b is fixed by the bolt 22. A part of the upper part of the oil pan upper 20b is notched in an arc shape, and the journal portion 21a of the crankshaft 21 is arranged in this notched part, and the crankshaft 21 is rotatably supported. A sprocket (not shown) is attached to the crankshaft 21, and the driving force of the crankshaft 21 is transmitted to the oil pump 1 by connecting the sprocket and the sprocket 11 of the oil pump 1 with a belt. Then, when the oil pump 1 is driven, the oil stored in the oil pan lower 20a is sucked from the pump suction hole 23b of the pump structure through the suction port 15, and is pressurized by the pump structure. It is discharged from the pump discharge hole 27 through the discharge passage and from the discharge port 16. The oil discharged from the discharge port 16 is supplied to the internal combustion engine.

In the conventional oil pump, when the oil discharged from the pump discharge hole 27 of the pump component reaches the discharge port 16 through the discharge passage, the discharge passage provided inside the first housing 2 and the second housing 3 Since the passage area is almost constant, the flow path resistance is large, and there is a risk that the oil flow rate required for the internal combustion engine cannot be sufficiently supplied. The means for solving this will be described with reference to FIGS. 11 and 12.

FIG. 11 is a sectional view taken along line XI-XI shown in FIG. FIG. 12 is a perspective view in which a part of the oil pump is broken. In this embodiment, the first direction and the second direction are defined as follows. As shown in FIG. 12, the first direction is a direction along the rotation axis of the drive shaft 4 which is a pump component, and the second direction is a direction orthogonal to the first direction.

The pump discharge hole 27 of the pump structure communicates with the communication hole 80 formed in the first housing 2. The communication hole 80 opens and extends along the first direction and communicates with one of the first passages 81. The first passage 81 extends in a second direction orthogonal to the first direction. The oil that has passed through the connecting hole 80 flows into the first passage 81, and the direction of flow in the second direction orthogonal to the first direction is changed. When the passage area of the communication hole 80 communicating with the pump discharge hole 27 is S1 and the passage area of the first passage 81 is S2, the passage area S2 of the first passage 81 is formed larger than the passage area S1 of the communication hole 80. (S2> S1). In this embodiment, since the passage area S2 of the first passage 81 is larger than the passage area S1 of the communication hole 80, the pulsation in the discharge passage can be reduced and the vibration of the oil pump can be suppressed.

The other side of the first passage 81 communicates with one of the expansion passages 82. The expansion passage 82 extends in the first direction, and is formed so that the passage area increases toward the downstream side. The oil that has passed through the first passage 81 flows into the expansion passage 82, and the direction of flow in the first direction orthogonal to the second direction is changed.

The other side of the expansion passage 82 communicates with one of the reduction passage 83. The reduced passage 83 extends in the first direction, and is formed so that the passage area becomes smaller toward the downstream side.

In this embodiment, the expansion passage 82 and the reduction passage 83 are formed in a short shape. Therefore, the oil pump 1 can be miniaturized.

The other side of the reduced passage 83 communicates with one of the second passage 84. The second passage 84 is formed so as to extend in the first direction and the third direction orthogonal to the second direction. In this embodiment, the second passage 84 extends downward. The second passage 84 has a discharge port 16.

A discharge port 16 of the oil pump 1 is provided on the other side of the second passage 84. The discharge port 16 communicates with the internal combustion engine. In this embodiment, a discharge passage is formed between the pump discharge hole 27 and the discharge port 16 connected to the internal combustion engine.

The communication hole 80, the first passage 81, and the expansion passage 82 of this embodiment are formed in the first housing 2 together with the pump component. Further, the reduced passage 83 and the second passage 84 of this embodiment are formed in the second housing 3. Then, the discharge passage is formed by arranging the second housing 3 so as to close the pump accommodating portion 2s of the first housing 2.

In this embodiment, since the expansion passage 82 and the reduction passage 83 are separately formed into the first housing 2 and the second housing 3, it is easy to form the passage.

The configuration of the expansion passage 82 will be described. The expanded passage 82 has a larger passage area as it approaches the discharge port 16 from the first passage 81. That is, the passage area S4 on the discharge port 16 side is larger than the passage area S3 on the first passage 81 side in the expanded passage 82 (S3 <S4). Further, the passage area S3 on the first passage 81 side and the passage area S2 of the first passage 81 are equal (S3 = S2). As a result, the passage area S4 on the discharge port 16 side of the expanded passage 82 is larger than the passage area S2 of the first passage 81 and the passage area S1 of the connecting hole 80 (S4> S2> S1). Thereby, the flow path resistance of the discharge passage from the connecting hole 80 to the expansion passage 82 can be reduced.

The expansion passage 82 is composed of a first expansion passage portion 82a extending in the first direction and a second expansion passage portion 82b provided at a position facing the first expansion passage portion 82a. The first expanded passage portion 82a and the second expanded passage portion 82b face each other with a virtual line (broken line in FIG. 11) as a boundary. The second expanded passage portion 82b is formed so that the distance from the first expanded passage portion 82a gradually increases as the distance from the first passage 81 approaches the reduced passage 83 (discharge port 16). The second expansion passage portion 82b is arranged on the crankshaft 21 side.

The expansion passage forming portion 85 forming the second expansion passage portion 82b is arranged so as to be inclined so that the reduction passage 83 side is located above the first passage 81 side. As a result, the second expansion passage portion 82b is inclined along the expansion passage forming portion 85.

The communication hole 80, the first passage 81, and the expansion passage 82 of this embodiment are formed in the first housing 2 together with the pump structure.

In this embodiment, since the expansion passage 82 whose passage area is expanded is formed in the discharge passage formed between the pump discharge hole 27 and the discharge port 16 connected to the internal combustion engine, the discharge passage The flow path resistance of the oil flowing inside can be reduced, and the necessary oil can be supplied to the internal combustion engine.

Next, the configuration of the reduced passage 83 will be described. The reduced passage 83 has a smaller passage area as it approaches the discharge port 16 from the expanded passage 82. That is, the passage area S6 on the discharge port 16 side is smaller than the passage area S5 on the expansion passage 82 side in the reduction passage 83 (S5> S6). Further, the passage area S5 on the expansion passage 82 side in the reduction passage 83 and the passage area S4 on the discharge port 16 side in the expansion passage 82 are equal (S5 = S4). As a result, the flow path resistance in the discharge passage due to the joint portion between the first housing 2 and the second housing 3 can be reduced, and the sealing property at the joint portion can be ensured.

The reduced passage 83 is composed of a first reduced passage portion 83a extending in the first direction and a second reduced passage portion 83b provided at a position facing the first reduced passage portion 83a. The first reduced passage portion 83a and the second reduced passage portion 83b face each other with a virtual line (broken line in FIG. 11) as a boundary. The first reduced passage portion 83a is located on the same side as the first expanded passage portion 82a and is connected to the first expanded passage portion 82a. The second reduced passage portion 83b is located on the same side as the second expanded passage portion 82b, and is connected to the first expanded passage portion 82a and the second expanded passage portion 82b.

The first reduced passage portion 83a is formed so that the distance from the expanded passage 82 to the second reduced passage portion 83b gradually decreases as it approaches the second passage 84 (discharge port 16). The second expansion passage portion 82b is arranged on the crankshaft 21 side.

The reduced passage forming portion 86 forming the first reduced passage portion 83a is arranged so as to be inclined so that the discharge port 16 side is located above the expanded passage 82 side. As a result, the first reduced passage portion 83a is inclined along the reduced passage forming portion 86. Further, the first reduced passage portion 83a and the second expanded passage portion 82b are arranged so as to be inclined in the same direction.

The reduced passage forming portion 86 forms a part of the second passage 84 and a part of the discharge port 16. The outer circumference of the discharge port 16 is a flange portion for connecting to a passage connected to the internal combustion engine. In this embodiment, since a part of the flange portion of the discharge port 16 is formed by the reduced wall thickness passage forming portion 86, the strength of the flange portion is ensured and the sealing property at the flange portion is ensured. , Oil leakage can be suppressed.

In this embodiment, the reduced passage 83 is formed so as to communicate with the expanded passage 82 and reduce the passage area. Since the oil flowing through the discharge passage passes through the expanded passage and the reduced passage, a vortex is generated in the discharge passage, and the pressure of the oil is relieved by the vortex. As a result, in this embodiment, the pulsation in the discharge passage can be reduced, and the vibration of the oil pump due to the pulsation can be reduced.

The passage area S7 of the discharge port 16 is equal to the passage area S6 on the discharge port 16 side in the reduced passage 83 (S7 = S6). Further, the passage area S6 on the discharge port 16 side in the reduced passage 83 and the passage area S3 on the first passage 81 side in the expanded passage 82 are equal (S6 = S3). As a result, the passage area S2 of the first passage 81, the passage area S3 on the first passage 81 side, the passage area S6 on the discharge port 16 side in the reduced passage 83, and the passage area S7 of the discharge port 16 are all equal (S2 = S3 =). S6 = S7).

Therefore, the passage area S7 of the discharge port 16 which is the outlet of the discharge passage is formed to be larger than the passage area S1 of the communication hole 80 which is the inlet of the discharge passage (S7> S1). In this embodiment, since the passage area S7 of the discharge port 16 is larger than the passage area S1 of the communication hole 80, the flow path resistance in the discharge passage can be reduced.

Next, comparing the lengths of the expansion passage 82 and the reduction passage 83 in the first direction, the length L1 of the expansion passage 82 is formed longer than the length L2 of the reduction passage 83. As a result, the section for rectifying the flow of oil discharged from the pump component can be lengthened, and vibration can be reduced.

As described above, according to this embodiment, it is possible to provide an oil pump capable of reducing the flow path resistance and supplying the flow rate of oil required for the internal combustion engine.

The present invention is not limited to the above-described embodiment, and includes various modifications. The above-described examples have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations.

This application claims priority based on Japanese Patent Application No. 2019-052386 filed on March 20, 2019. The entire disclosure, including the specification, claims, drawings, and abstract of Japanese Patent Application No. 2019-052386 filed March 20, 2019, is incorporated herein by reference in its entirety.

1 ... Oil pump, 2 ... 1st housing, 2s ... Pump housing, 3 ... 2nd housing, 4 ... Drive shaft, 6 ... Control ring, 7 ... Pilot valve, 9 ... Pivot pin, 11 ... Sprocket, 15 ... Suction Port, 16 ... Discharge port, 17 ... Check valve, 20 ... Oil pan, 20a ... Oil pan lower, 20b ... Oil pan upper, 21 ... Crankshaft, 23a ... Suction port, 23b ... Pump suction hole, 24a ... Discharge port, 27 ... Pump discharge hole, 80 ... Communication hole, 81 ... First passage, 82 ... Expansion passage, 82a ... First expansion passage, 82b ... Second expansion passage, 83 ... Reduction passage, 83a ... First reduction passage , 83b ... Second reduced passage portion, 84 ... Second passage, 85 ... Expanded passage forming portion, 86 ... Reduced passage forming portion

Claims

An oil pump for an internal combustion engine.
A housing with a pump housing inside,
A pump structure that is housed in the pump accommodating portion and is rotationally driven to discharge oil sucked from the pump suction hole from the pump discharge hole.
A discharge passage formed between the pump discharge hole and a discharge port connected to the internal combustion engine is provided.
The discharge passage
It communicates with the pump discharge hole extending in the first direction, which is the direction along the rotation axis of the pump structure, and extends in the second direction orthogonal to the first direction, and is larger than the passage area of the pump discharge hole. The formed first passage and
An expanded passage that communicates with the first passage and extends in the second direction, and the passage area increases as the passage approaches the discharge port from the first passage.
An oil pump characterized by being equipped with.
In the oil pump according to claim 1,
The discharge passage
An oil pump comprising a reduced passage that communicates with the expanded passage and whose passage area becomes smaller as it approaches the discharge port from the expanded passage.
In the oil pump according to claim 2,
The discharge passage
An oil pump comprising a second passage that communicates with the reduced passage, extends in the first direction and a third direction orthogonal to the second direction, and has the discharge port.
In the oil pump according to claim 3,
The expansion passage
The first expansion passage portion extending in the second direction and the
A second expansion passage provided at a position facing the first expansion passage portion, and formed so that the distance between the first expansion passage and the first expansion passage gradually increases as the distance from the first passage approaches the reduction passage. With a part,
The reduced passage
The second reduced passage portion located on the same side as the second expanded passage portion and
It is located on the same side as the first expansion passage portion and is provided at a position facing the second reduction passage portion, and the closer to the second passage from the expansion passage, the distance between the second reduction passage portion and the second reduction passage portion. An oil pump characterized by comprising a first reduced passage portion formed so as to be smaller in size.
In the oil pump according to claim 4,
The second enlarged passage portion is formed so as to be inclined so that the reduced passage side is located above the first passage side.
The oil pump is characterized in that the second reduced passage portion is formed so as to be inclined in the same direction as the second expanded passage portion.
In the oil pump according to claim 4,
The oil pump characterized in that the second expansion passage portion is arranged on the crankshaft side provided in the internal combustion engine.
In the oil pump according to claim 2,
An oil pump characterized in that, in the second direction, the expansion passage is formed longer than the reduction passage.
In the oil pump according to claim 2,
The housing has a first housing in which the pump accommodating portion for accommodating the pump component is formed, and a second housing for closing the pump accommodating portion.
The expansion passage is provided in the first housing.
The reduced passage is an oil pump provided in the second housing.
In the oil pump according to claim 1,
The oil pump includes a pump discharge hole and a communication hole communicating with the first passage.
The oil pump is characterized in that the first passage is formed larger than the passage area of the communication hole.
In the oil pump according to claim 1,
The oil pump includes a pump discharge hole and a communication hole that communicates with the first passage.
An oil pump characterized in that the passage area of the discharge port is formed to be larger than the passage area of the communication hole.
In the oil pump according to claim 2,
An oil pump characterized in that the expansion passage or the reduction passage is formed in a short shape.