JP6390379B2 - Oil pump - Google Patents

Description

  The present invention relates to a variable displacement oil pump.

  Conventionally, as a variable displacement type oil pump capable of changing the suction amount and discharge amount of a pump, for example, an inner rotor having external teeth and driven around a driving rotation axis, and an inner meshing engagement with the inner rotor in an eccentric state Some have a casing with an outer rotor that has teeth and rotates around a driven axis. In order to change the discharge amount, an adjustment ring is provided that revolves the driven axis of the outer rotor around the drive rotation axis while the inner rotor and the outer rotor are engaged with each other (for example, Patent Document 1). .

  In the oil pump shown in Patent Document 1, the adjustment ring is displaced to change the meshing state between the outer teeth of the inner rotor and the inner teeth of the outer rotor, thereby changing the pump discharge amount. In order to displace the adjustment ring, a guide pin protrudes from the bottom surface of the casing, and the guide pin slides along a guide hole formed in the protruding portion of the adjustment ring.

JP, 2014-139420, A

  When changing the discharge amount of the pump, the position of the adjustment ring is maintained by the guide pin coming into contact with the edge of the guide hole. However, when the contact between the edge portion of the guide hole and the guide pin is repeated, at least one of the edge portion of the guide hole and the guide pin is worn and wear powder is generated. If wear powder exists between the guide pin and the guide hole, the adjustment ring is not held at the intended control position, and the pump discharge amount cannot be changed appropriately. Further, if the wear powder continues to contact the guide pins and the guide holes, the wear of each member may further progress.

  In view of the above problems, an object of the present invention is to provide an oil pump that can satisfactorily maintain the variable function of the discharge amount of the pump.

The first characteristic configuration of the oil pump according to the present invention includes a plurality of external teeth, an inner rotor that rotates around a first rotation axis,
An outer rotor that is formed in an annular shape having a plurality of internal teeth that mesh with the external teeth, and that rotates according to the rotation of the inner rotor at a second rotational axis that is eccentric with respect to the first rotational axis;
A suction port that supplies oil between the external teeth and the internal teeth, and a discharge port that discharges oil supplied from the suction ports as the inner rotor rotates from between the external teeth and the internal teeth And a casing enclosing the inner rotor and the outer rotor;
An adjustment ring that supports the outer rotor so as to be relatively rotatable from the radially outer side in a state where the outer teeth and the inner teeth mesh with each other;
An operation unit provided on an outer peripheral surface of the adjustment ring, to which a driving force is input;
A guide recess provided on one member of the casing and the adjustment ring, and a guide protrusion provided on the other member of the casing and the adjustment ring, and inserted into the recess, As the convex portion moves relative to the concave portion, the second rotation axis revolves around the first rotation axis according to the driving force input to the operation portion. A guide portion for guiding the adjustment ring,
It is in the point provided with the foreign substance reservoir part provided in the site | part adjacent to the edge part of the said recessed part in said one member, or the base end part of the said convex part in said other member.

As in this configuration, of the concave and convex portions constituting the guide portion, a foreign substance reservoir is provided at the edge of the concave portion or at a portion adjacent to the base end portion of the convex portion. Foreign matter (abrasion powder) generated by contact can be accumulated in the foreign matter reservoir. Thereby, the recessed part and convex part which comprise a guide part contact | abut appropriately, and the discharge amount of a pump can be changed appropriately.
Further, by removing foreign matter (abrasion powder) from the portion where the concave portion and the convex portion abut, it is possible to suppress the progress of wear of the concave portion and the convex portion.

  Another characteristic configuration of the oil pump according to the present invention is that the foreign substance reservoir is provided at least at one of both ends in the direction in which the convex portion moves relative to the concave portion for guide provided in the one member. There is in point.

  The foreign matter is generated when the convex portion slides mainly along the concave portion serving as a guide groove. The foreign matter generated at this time moves inside the concave portion together with the convex portion, and reaches the end portion of the concave portion. The relative movement between the concave portion and the convex portion becomes zero at the end portion of the concave portion, and even if the convex portion starts to move again in the opposite direction, the convex portion does not immediately move at a high speed. Therefore, the foreign material once carried to the edge part of a recessed part is rarely taken out with a convex part again. For this reason, as in the present configuration, the foreign substance reservoir can be efficiently stored by providing the foreign substance reservoir at at least one end of the guide recess provided on one member.

  Another feature of the oil pump according to the present invention is that the foreign substance reservoir is provided in a portion of the other member adjacent to a portion of the base end of the convex portion that contacts the end of the concave portion. There is in point.

  As described above, the foreign matter generated when the convex portion slides along the concave portion moves in the concave portion together with the convex portion, and reaches the end portion of the concave portion. Here, as in the present configuration, when the foreign material reservoir is provided in a portion of the other member adjacent to the portion of the base end portion of the convex portion that contacts the end portion of the concave portion, the convex portion is the concave portion. When moving from the end in the opposite direction, the foreign substance reservoir is located in the space between the convex and concave portions. For this reason, the foreign substance carried to the edge part of the recessed part by the convex part becomes easy to be stored in the foreign substance reservoir part.

  Another feature of the oil pump according to the present invention is that, when the casing is in a mounting posture with respect to the vehicle, the foreign substance reservoir is provided in the recess when the foreign member reservoir is provided on the one member. When the foreign material reservoir is provided on the other member, the foreign material reservoir is provided on the lower side of the gravity direction with respect to the convex portion. It is in.

  Foreign matter such as wear powder usually descends in the direction of gravity. Therefore, in this configuration, when the casing is in the mounting posture with respect to the vehicle, when the foreign substance reservoir is provided on one member, the foreign substance reservoir is provided below the concave portion in the gravity direction, In the case where the other member is provided with a foreign substance reservoir, the foreign substance reservoir is provided below the convex portion in the direction of gravity. Thereby, the foreign material (wear powder) can be efficiently stored in the foreign material reservoir, and the stored foreign material (wear powder) is easily held in the foreign material reservoir.

It is sectional drawing of the oil pump in a pump capacity | capacitance maximum state. It is sectional drawing of the oil pump in a pump capacity minimum state. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1. FIG. 4 is a cross-sectional view taken along arrow IV-IV in FIG. 2. It is a figure which shows the foreign material reservoir part of 2nd Embodiment. It is VI-VI arrow sectional drawing of FIG. It is a figure which shows the foreign material reservoir part (lower side of the gravity direction of a convex part) of another form. It is a figure which shows the foreign material reservoir part (lower side of the gravity direction of a recessed part) of another form. It is a figure which shows the foreign material reservoir part (lower side of the gravity direction of a recessed part) of another form. It is a figure which shows the foreign material reservoir part of another form.

Hereinafter, the oil pump 100 of this embodiment is demonstrated based on drawing.
FIG. 1 shows a variable displacement oil pump 100 whose discharge pressure can be changed as an example of the oil pump. For example, the oil pump 100 is mounted on a vehicle and driven by an engine of the vehicle. The applications include supplying oil for lubricating the engine and supplying oil to hydraulic equipment such as a valve timing control device for the engine.

  The oil pump 100 includes an inner rotor 12, an outer rotor 13, an adjustment ring 14, a suction port 2, a discharge port 3, an arm portion 54, a guide portion 30, and the like inside the casing 1.

  The inner rotor 12 is formed in an annular shape, and a plurality of external teeth 12A are provided on the outer peripheral surface thereof. The external teeth 12A are configured in a tooth surface shape according to a trochoid curve, a cycloid curve, or the like. The inner rotor 12 rotates around the first rotation axis X. In the present embodiment, the rotational power of the engine is transmitted to the inner rotor 12. The inner rotor 12 is disposed coaxially with the first rotation axis X, and is rotatably supported with respect to the casing 1 via the drive shaft 11. When the rotational power of the engine is transmitted to the drive shaft 11, the inner rotor 12 rotates integrally with the drive shaft 11.

  The outer rotor 13 is formed in an annular shape, and a plurality of inner teeth 13A that mesh with the outer teeth 12A of the inner rotor 12 are provided on the inner peripheral surface thereof. The outer rotor 13 rotates around the second rotation axis Y that is eccentric with respect to the first rotation axis X in response to the rotation of the inner rotor 12. The inner teeth 13 </ b> A of the outer rotor 13 are configured to have one more tooth than the outer teeth 12 </ b> A of the inner rotor 12. When the outer rotor 13 rotates, the inner teeth 13 </ b> A of the outer rotor 13 come into contact with the outer teeth 12 </ b> A of the inner rotor 12. Therefore, a predetermined gap Q is formed between the outer teeth 12A and the inner teeth 13A.

  A suction port 2 and a discharge port 3 are formed in the casing 1. The suction port 2 and the discharge port 3 are openings formed in the wall 1 </ b> A of the casing 1. Specifically, the suction port 2 and the discharge port 3 are provided on the wall portion 1A facing the axial end surface of the outer rotor 13 among the inner walls on both sides of the casing 1, and are provided along the radial direction of the outer rotor 13. It is done. That is, the suction port 2 and the discharge port 3 are provided in the wall portion 1A facing the same direction.

  Oil is supplied from the suction port 2 between the outer teeth 12A and the inner teeth 13A (gap Q). The opening constituting the discharge port 3 is provided along the radial direction of the outer rotor 13 at a position spaced apart from the opening constituting the suction port 2. As the inner rotor 12 rotates, the oil supplied from the suction port 2 is discharged to the discharge port 3 from between the outer teeth 12A and the inner teeth 13A (gap Q).

  The inner rotor 12 rotates in the direction of arrow A together with the drive shaft 11. When the adjustment ring 14 is in the posture (initial position) shown in FIG. 1, the suction port is placed in the negative pressure acting region where the pressure of the oil is reduced between the outer teeth 12 </ b> A of the inner rotor 12 and the inner teeth 13 </ b> A of the outer rotor 13. 2 are opposed to each other, and the discharge port 3 is opposed to a positive pressure acting region in which oil is compressed between the outer teeth 12A of the inner rotor 12 and the inner teeth 13A of the outer rotor 13. This functions to suck oil from the suction port 2 and send oil from the discharge port 3.

  The adjustment ring 14 supports the outer rotor 13 so as to be relatively rotatable from the outside in the radial direction in a state where the outer teeth 12A and the inner teeth 13A are engaged with each other. The adjustment ring 14 is formed in a ring shape having an inner peripheral surface coaxial with the second rotation axis Y so as to insert the outer rotor 13 therein. The outer periphery of the outer rotor 13 is formed in a circular shape centered on the second rotation axis Y. Thereby, the center of the inner periphery of the adjustment ring 14 and the second rotational axis Y of the outer rotor 13 coincide with each other, and the outer peripheral surface of the outer rotor 13 can be supported by the inner peripheral surface of the adjustment ring 14.

  The adjustment ring 14 is provided with an arm portion 54 that protrudes in a direction away from the second rotation axis Y on the outer peripheral surface thereof. A driving force is input to the arm portion 54. In the present embodiment, the arm unit 54 corresponds to the operation unit. The driving force is a driving force that revolves the second rotational axis Y of the outer rotor 13 around the first rotational axis X of the inner rotor 12 as described later. Here, the outer rotor 13 is accommodated in the adjustment ring 14 so as to be relatively rotatable. For this reason, the adjustment ring 14 revolves around the first rotation axis X as the second rotation axis Y revolves. Therefore, the driving force input to the arm portion (operation unit) 54 corresponds to a driving force for revolving the adjustment ring 14 itself.

  The guide unit 30 is provided in the casing 1 and the adjustment ring 14, and the second rotation axis Y is centered on the first rotation axis X according to the driving force input to the arm unit (operation unit) 54. The adjustment ring 14 is guided to revolve. In the present embodiment, guide recesses 31 are formed at two locations on the outer peripheral surface of the adjustment ring 14. On the wall portion 1 </ b> A of the casing 1, a guide convex portion 32 that protrudes in parallel with the first rotation axis X is formed to protrude. The protruding ends of these two convex portions 32 are fitted into the concave portions 31, respectively. The guide part 30 includes two convex parts 32 and two concave parts 31.

  A sealing material 37 is disposed at a position facing the casing 1 of the arm portion 54. In the outer peripheral portion of the adjustment ring 14, a protruding portion 36 is formed at a position opposite to the arm portion 54, and a sealing material 37 is disposed at a position facing the casing 1 of the protruding portion 36. Thus, the arm portion 54 and the overhang portion 36 are in sliding contact with the inner surface of the wall portion of the casing 1.

  The pressure of oil discharged from the discharge port 3 (hereinafter referred to as discharge pressure) is supplied to the pressure chamber 52 from the electromagnetic valve V via the oil filter 55 and further acts on the arm portion 54. The arm portion 54 is provided with a coil spring 6 that is biased to the side opposite to the direction in which the discharge pressure of the discharge port 3 acts.

  The protruding end of the arm portion 54 is in sliding contact with the inner peripheral surface of the casing 1 when the adjustment ring 14 is operated. The oil supplied to the pressure chamber 52 operates the adjusting ring 14 without leaking. When the adjustment ring 14 moves from the posture shown in FIG. 1 to the posture shown in FIG. 2, the oil pump 100 has a second meshing relationship between the outer teeth 12 </ b> A of the inner rotor 12 and the inner teeth 13 </ b> A of the outer rotor 13. The rotation axis Y is configured to reach a positional relationship obtained by revolving 90 degrees.

  The discharge pressure detection unit 17 includes a pressure sensor that detects the discharge pressure of the discharge port 3. In the present embodiment, the discharge pressure detection unit 17 detects the discharge pressure supplied to the main gallery M.

  The driving force control unit 16 controls the driving force input to the arm unit (operation unit) so that the discharge pressure detected by the discharge pressure detection unit 17 becomes the required oil pressure. In the present embodiment, the required oil pressure is preset according to the engine speed. This is because the hydraulic pressure required for the main gallery M differs depending on the engine speed.

  The driving force control unit 16 is configured by an engine control unit (ECU) or the like, and controls the electromagnetic valve V based on the required oil pressure. As a specific example of the control, a low pressure control mode, a high pressure control mode, and a DUTY control mode for repeatedly changing the low pressure control mode and the high pressure control mode are set. Specifically, it may be changed between the low pressure control and the high pressure control, or may be changed by appropriately setting each DUTY.

  In the high pressure control mode (FIG. 1), the solenoid valve V is set to a position that prevents the discharge pressure from escaping and opens the pressure chamber 52 to the atmosphere. Thereby, the adjustment ring 14 can be operated by the urging force of the coil spring 6 against the arm portion 54.

  In the low pressure control mode (FIG. 2), the solenoid valve V is set to a position for increasing the discharge pressure. As a result, the adjustment ring 14 can be operated against the urging force of the coil spring 6 by applying the discharge pressure to the arm portion 54.

  Thus, by setting the driving force control unit 16 to the low pressure control mode, the discharge amount of the oil pump 100 is reduced when the engine speed is low, or the oil pump 100 is set when the engine speed is high. The discharge amount can be reduced. As a result, an excessive amount of oil is discharged based on the conditions, or the discharge pressure is excessively increased to suppress the inconvenience of deteriorating the fuel consumption of the engine.

  The driving force control unit 16 controls the solenoid valve V so that the detection result of the discharge pressure detection unit 17 matches the required hydraulic pressure set according to the current engine speed, and inputs the control valve 14 to the adjustment ring 14. The driving force to be controlled is controlled by feedback control.

  Thus, in the high pressure control mode (FIG. 1), the drive shaft 11 is driven and rotated as described above, whereby oil is sucked from the suction port 2 and oil is discharged from the discharge port 3.

  On the other hand, in the low pressure control mode (FIG. 2), the second rotating shaft Y is revolved around the first rotating shaft X, and the adjusting ring 14 is also moved to the second rotating shaft Y. Rotate around. Therefore, at this time, the outer rotor 13 also moves together, and the second rotation axis Y revolves around the first rotation axis X in a state where the outer teeth 12A of the inner rotor 12 are engaged with the inner teeth 13A of the outer rotor 13.

  In this way, the adjustment ring 14 revolves 90 degrees around the second rotation axis Y. When the adjustment ring 14 moves to the moving end position in the high pressure control mode or the low pressure control mode, the edges 31 a and 31 b of the recess 31 abut on the protrusion 32 in the guide portion 30 and are held in position. Here, the casing 1 and the adjustment ring 14 in which the guide portion 30 is provided are usually made of a metal material, and the concave portion 31 and the convex portion 32 are similarly made of a metal material.

  For this reason, when the recessed part 31 and the convex part 32 repeat contact | abutting and separation | spacing, the recessed part 31 or the convex part 32 may be worn out and may generate | occur | produce abrasion powder as a foreign material. If such foreign matter (abrasion powder) is caught between the concave portion 31 and the convex portion 32, even if the driving force control unit 16 tries to control the discharge pressure to the desired hydraulic pressure, the second rotational axis Y is There is a case where the revolution does not revolve around the rotation axis X by the amount corresponding to the intended angle, and the target hydraulic pressure is not reached.

  For example, if a foreign object bites between the edge 31b on the front side of the concave portion 31 in the clockwise direction and the convex portion 32, the adjustment ring 14 cannot move to the position of the low pressure control mode (FIG. 2). Therefore, the required oil pressure cannot be maintained.

  In order to store such foreign matter (wear powder), the guide portion 30 includes a foreign matter reservoir 60. As shown in FIGS. 1 to 4, the foreign substance reservoir 60 is provided in a portion adjacent to the proximal end portion 32 a of the convex portion 32 in the casing 1 provided with the convex portion 32. The foreign matter reservoir 60 is configured by a hole 61 formed on the front side of the convex portion 32 in the clockwise direction. Further, the hole 61 is formed with a size smaller than the diameter of the convex portion 32 so as not to be affected by the oil pressure inside the casing 1.

  By providing the foreign material reservoir 60 at a portion adjacent to the base end portion 32 a of the convex portion 32 constituting the guide portion 30, the foreign matter (wear powder) J generated by the sliding contact between the convex portion 32 and the concave portion 31 is removed as a foreign matter. It can be stored in the reservoir 60. Thereby, the guide function of the recessed part 31 and the convex part 32 can be maintained favorable, and the discharge amount of a pump can be changed appropriately.

In the present embodiment, the hole 61 is provided in a portion of the casing 1 adjacent to the portion of the base end portion of the convex portion 32 that contacts the end portion 31 b of the concave portion 31. The foreign matter J generated when the convex portion slides along the concave portion 31 moves inside the concave portion 31 together with the convex portion 32 and reaches the end portions 31 a and 31 b of the concave portion 31. Here, the hole 61 is located between the convex portion 32 and the end portion 31 b of the concave portion 31 when the convex portion 32 moves in the opposite direction from the end portion 31 b of the concave portion 31. For this reason, the foreign matter carried to the end portion 31 b of the concave portion 31 by the convex portion 32 is easily stored in the hole portion 61.
In addition, the hole 61 may be provided in a portion of the casing 1 adjacent to the portion of the base end portion of the convex portion 32 that is in contact with the end portion 31 a on the opposite side of the concave portion 31.

[Second Embodiment]
In the present embodiment, as shown in FIGS. 5 and 6, the foreign substance reservoir 60 is provided at the ends (edges) 31 a and 31 b of the recess 31 of the adjustment ring 14. The foreign matter reservoir 60 is a groove 62 formed in the ends (edges) 31 a and 31 b of the recess 31. The foreign substance reservoir 60 may be provided at both ends (31a, 31b) of the concave portion 31 in the direction in which the convex portion 32 relatively moves, or may be provided only at one end (31a or 31b).

As described above, the foreign matter J moves in the concave portion 31 together with the convex portion 32 and reaches the end portions 31 a and 31 b of the concave portion 31. At the end portions 31a and 31b of the concave portion 31, the relative movement between the concave portion 31 and the convex portion 32 becomes zero, and even if the convex portion 32 starts to move again in the opposite direction, the convex portion 32 does not immediately move at a high speed. Absent. Therefore, the frequency with which the foreign matter J once carried to the end portions 31a and 31b of the concave portion 31 is taken out together with the convex portion 32 is low. For this reason, the foreign material J can be efficiently stored by providing the groove part 62 in the edge part 31a, 31b of the recessed part 31 for guides provided in the adjustment ring 14. FIG.
In addition, the width of the groove 62 is configured to be smaller than the diameter of the convex portion 32 so that the convex portion 32 does not come into contact with the foreign substance reservoir 60.

[Other Embodiments]
(1) In the above embodiment, an example in which the guide portion 30 is configured by the concave portion 31 provided in the adjustment ring 14 and the convex portion 32 provided in the casing 1 has been described. The adjustment ring 14 may be provided with the convex portion 32 and the casing 1 may be provided with the concave portion 31.

(2) When the casing 1 is in the mounting posture with respect to the vehicle and the foreign member reservoir 60 is provided on the other member having the convex portion 32, for example, as shown in FIG. The part 60 may be provided below the convex part 32 in the direction of gravity (downward on the paper surface). When the foreign matter reservoir 60 is provided on one member having the recess 31, the foreign matter reservoir 60 is below the gravity direction (downward on the paper) with respect to the recess 31 as shown in FIGS. 8 and 9. It may be provided. In the example shown in FIG. 8, the foreign substance reservoir 60 is provided at three locations on the left and right sides and the center side of the recess 31.

(3) In the said embodiment, the example provided with the foreign material reservoir part 60 only in any one among the one member (casing 1) provided with the convex part 32 and the other member (adjustment ring 14) provided with the recessed part 31 is shown. However, the foreign substance reservoir 60 may be provided on both the member including the convex portion 32 and the member including the concave portion 31.

(4) As shown in FIG. 10, the foreign matter reservoir 60 may include a magnet 63. The magnet 63 is disposed, for example, at the bottom of the foreign material reservoir 60 or the like. As described above, the guide portion 30 (the concave portion 31 and the convex portion 32) is made of a metal material. For this reason, the foreign matter (wear powder) J can be adsorbed using the magnetic force of the magnet 63. As a result, the foreign matter J is easily stored in the foreign matter reservoir 60. Further, the foreign matter J is attracted to the magnet 63 so that the foreign matter J is easily held in the foreign matter reservoir 60.

  The present invention can be used for a variable displacement oil pump.

DESCRIPTION OF SYMBOLS 1 Casing 2 Suction port 3 Discharge port 12 Inner rotor 12A Outer tooth 13 Outer rotor 13A Inner tooth 14 Adjustment ring 30 Guide part 31 Recessed part 31a, 31b End part (edge part)
32 Convex part 32a Base end part 54 Arm part (operation part)
60 Foreign matter reservoir 100 Oil pump J Foreign matter (wear powder)

Claims (4)

An inner rotor having a plurality of external teeth and rotating about a first rotation axis;
An outer rotor that is formed in an annular shape having a plurality of internal teeth that mesh with the external teeth, and that rotates according to the rotation of the inner rotor at a second rotational axis that is eccentric with respect to the first rotational axis;
A suction port that supplies oil between the external teeth and the internal teeth, and a discharge port that discharges oil supplied from the suction ports as the inner rotor rotates from between the external teeth and the internal teeth And a casing enclosing the inner rotor and the outer rotor;
An adjustment ring that supports the outer rotor so as to be relatively rotatable from the radially outer side in a state where the outer teeth and the inner teeth mesh with each other;
An operation unit provided on an outer peripheral surface of the adjustment ring, to which a driving force is input;
A guide recess provided on one member of the casing and the adjustment ring, and a guide protrusion provided on the other member of the casing and the adjustment ring, and inserted into the recess, As the convex portion moves relative to the concave portion, the second rotation axis revolves around the first rotation axis according to the driving force input to the operation portion. A guide portion for guiding the adjustment ring,
An oil pump comprising a foreign substance reservoir provided at an edge of the concave portion of the one member or a portion adjacent to a base end portion of the convex portion of the other member.   2. The oil pump according to claim 1, wherein the foreign substance reservoir is provided in at least one of both ends in a direction in which the convex portion relatively moves in the concave portion for guide provided in the one member.   3. The oil pump according to claim 1, wherein the foreign substance reservoir is provided in a portion of the other member adjacent to a portion of the base end portion of the convex portion that contacts the end portion of the concave portion.   When the casing is in the mounting posture with respect to the vehicle, when the foreign substance reservoir is provided in the one member, the foreign substance reservoir is provided below the concave portion in the direction of gravity, The oil according to any one of claims 1 to 3, wherein when the foreign material reservoir is provided on the other member, the foreign material reservoir is provided below the convex portion in the direction of gravity. pump.

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