JP2001263268A - Oil pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain generation of an abnormal sound by reducing pulsation of hydraulic pressure by preventing a high pressure hydraulic fluid flowed in a sub-suction port via a control valve from a delivery port from flowing in a main suction port via a pump chamber from the sub-suction port. SOLUTION: A shape B1 of an anti-rotational directional side end part in the main suction port B of an oil pump 20 is formed in the shape of running along a rotational directional side end part shape R1 of the pump chamber R (an oblique line applied part) instantaneously sealed between the sub-suction port A and the main suction port B, and a shape A1 of an inner peripheral side end part in the sub-suction port A is formed in the shape of running along a rotational locus of the anti-rotational directional side end R2 (a contact point of both rotors 22 and 23) of the pump chamber R instantaneously sealed between the sub-suction port A and the main suction port B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil pump device, and more particularly to an oil pump device which is driven to rotate by a drive source and a control valve which can recirculate a part of hydraulic oil discharged from the oil pump. The present invention relates to an oil pump device for pumping a predetermined amount of hydraulic oil to a portion to be supplied.

[0002]

2. Description of the Related Art As one of such oil pump devices, there is an oil pump device disclosed in Japanese Patent Application Laid-Open No. Hei 10-73084.
The oil pump has a main suction port that is always in communication with the suction port, a sub suction port that is communicated with and shut off from the main suction port via the control valve, and a discharge port that is always in communication with the discharge port, A single oil pump is employed in which a plurality of pump chambers (variable volume chambers formed between an inner rotor and an outer rotor) formed in the circumferential direction are rotationally shifted to sequentially communicate with the ports. I have.

[0003] In the oil pump having the above structure,
The shape of the end of the main suction port on the side of the sub suction port is shaped along the shape of the end of the main suction port of the pump chamber which is momentarily sealed between the sub suction port and the main suction port. The shape of the end of the main suction port side of the port is in accordance with the shape of the sub suction port side end of the pump chamber which is momentarily sealed between the sub suction port and the main suction port, and is formed immediately before the pump chamber is sealed. And immediately after opening, a necessary and sufficient flow passage is secured.

[0004]

By the way, the configuration of the oil pump disclosed in the above-mentioned publication is changed to, for example, the oil pump 20 employing the four-leaf and five-node inner rotor 22 and the outer rotor 23 shown in FIG. In this case, the shape B1 of the sub suction port A side end of the main suction port B is instantaneously located between the sub suction port A and the main suction port B as shown by the two-dot chain line in FIG. The shape of the sealed pump chamber R (the shaded portion) follows the shape R1 of the main suction port side end, and the shape Ao of the main suction port side end of the sub suction port A.
However, as shown by the one-dot chain line in FIG. 1, the pump chamber R is instantaneously sealed in a shape along the sub-suction port side end shape R2 (an arc shape bulging inward).

In such a configuration, when both the rotors 22 and 23 rotate counterclockwise in FIG. 1 and the pump chamber R rotates and shifts to the position shown in FIG. It communicates with the main suction port B and the pump chamber R
Of the sub-suction port A indicated by the alternate long and short dash line overlaps and communicates. Therefore, when the sub-suction port A and the discharge port C are in communication with each other by the operation of the control valve 30, the sub-suction port A and the main suction port B repeat communication and non-communication through the pump chamber R. The high-pressure hydraulic fluid flowing from the discharge port C to the sub-suction port A via the control valve 30 is supplied to the sub-suction port A.
, Intermittently flows into the main suction port B via the pump chamber R, and the amount of oil is reduced in the portion to be supplied and the pulsation of the hydraulic pressure is increased, thereby causing abnormal noise.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to address the above-described problems, and has an oil pump that is driven to rotate by a drive source and a part of hydraulic oil that is discharged from the oil pump. In an oil pump device configured by a control valve capable of recirculating and supplying a predetermined amount of hydraulic oil to a portion to be supplied, as the oil pump, a main suction port that is always in communication with a suction port, and the main suction port is connected to the main suction port. A plurality of pump chambers formed in a circumferential direction having a sub-suction port that is communicated / blocked through a control valve and a discharge port that is always in communication with the discharge port, and the sub-suction port, A single oil pump is used to communicate with the main suction port and the discharge port sequentially. The shape along the rotational end of the pump chamber that is momentarily sealed between the sub suction port and the main suction port, and the shape of the inner peripheral end of the sub suction port. The pump chamber is characterized in that it is shaped along the rotation locus of the pump chamber, which is momentarily sealed between the sub suction port and the main suction port, at the end in the non-rotational direction. In this case, the pump chamber may be a variable volume chamber formed between the inner rotor and the outer rotor that are eccentrically arranged.

[0007]

In the oil pump device according to the present invention, when the pump chamber is momentarily rotated in the direction in which it communicates with the main suction port by the above configuration, the end of the pump chamber in the direction of rotation is rotated. Although the portion communicates with the main suction port, the end of the pump chamber on the opposite side in the non-rotational direction does not overlap with the sub suction port, and does not communicate with the sub suction port. Therefore, even if the sub suction port and the discharge port communicate with each other due to the operation of the control valve, the sub suction port and the main suction port do not communicate with each other through the pump chamber, and the sub suction port and the main suction port communicate with each other through the control valve. The high-pressure hydraulic oil flowing into the suction port does not flow from the sub-suction port to the main suction port via the pump chamber, so that it is possible to suppress a decrease in the amount of oil in the portion to be supplied and to reduce the pulsation of the hydraulic pressure. Generation of abnormal noise can be suppressed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The oil pump device schematically shown in FIG. 1 includes an oil pump 20 that is rotationally driven by a crankshaft 10 of a vehicle engine (internal combustion engine).
And a control valve 30 that can recirculate a part of the hydraulic oil discharged from the oil pump 20 to the suction side. That is, it is configured to be pressure-fed to a hydraulically operated actuator of a variable valve mechanism in the engine, a lubricated portion such as a bearing in the engine, and an oil-cooled portion such as a cylinder or a piston in the engine. In addition, it is configured that the working oil is returned from the supplied part 50 to the oil pan 40 of the engine through the discharge path 42.

The oil pump 20 includes a crankshaft 1
0, the pump housing 21 is rotatably driven in the counterclockwise direction in FIG. 1, and an inner rotor 22 rotatably mounted in the pump housing 21 and rotatably driven by the crankshaft 10. The inner rotor 22 is eccentrically fixed by a predetermined amount and is rotatably assembled in the pump housing 21. The inner rotor 22 has five internal teeth 23 a which are fitted with four outer teeth 22 a in the same direction. The outer rotor 23 is rotated. The outer teeth 22a and the inner teeth 23a are defined by a trochoid curve or a cycloid curve.

The pump housing 21 is connected to a suction passage 43 and is connected to an oil pan 40 through a suction port (not shown).
, A discharge port (not shown) connected to the discharge path 41, a main suction port B constantly communicating with the suction port, and a sub suction port A that is communicated with and blocked from the main suction port B via the control valve 30. And the discharge port C which is always in communication with the discharge port
And the ports A, B, and C do not communicate with each other via the pump chambers R formed between the external teeth 22a and the internal teeth 23a.

In this embodiment, as shown in FIG. 1 and FIG. 2, the shape B1 of the main suction port B of the oil pump 20 in the anti-rotational direction is different from the sub suction port A and the main suction port. The shape of the pump chamber R (hatched portion) which is instantaneously sealed between the shape B and the rotational end shape R1 is the same as the shape A1 of the inner circumferential end of the sub suction port A. Is a rotation locus L of the pump chamber R, which is momentarily sealed between the sub suction port A and the main suction port B, on the non-rotational side end R2 (the point of contact between the rotors 22 and 23) (dotted line in FIG. 2). Reference).

For this reason, when both the rotors 21 and 22 rotate counterclockwise, the pump chamber R momentarily rotates and shifts in a direction communicating with the main suction port B (FIG. 1).
2), the rotation chamber side end of the pump chamber R communicates with the main suction port B, but the counter rotation direction end of the pump chamber R is connected to the sub suction port A.
And does not communicate with the sub suction port A. For this reason, even if the sub suction port A and the discharge port C are communicated via the control valve 30 by the operation of the control valve 30 described later, the sub suction port A and the main suction port B
Does not communicate through the pump chamber R, and the high-pressure hydraulic fluid flowing from the discharge port C into the sub suction port A via the control valve 30 flows from the sub suction port A via the pump chamber R to the main suction port. It is possible to suppress a decrease in the amount of oil in the fed section 50 without flowing into the portion B, and to reduce the generation of abnormal noise by reducing the pulsation of the hydraulic pressure.

As shown in FIGS. 1 and 3 to 6, the control valve 30 has an inner hole 31a.
control port 31b, sub port 3 communicating with
1c, valve housing 3 having main port 31d
1 (integrally formed with the pump housing 21)
And a pressure (discharge pressure of the oil pump 20) of the hydraulic oil flowing through the control port 31b at the left end of the valve housing 31 while being slidably mounted in the inner hole 31a of the valve housing 31 in the axial direction. And the variable throttle portions O1 and O2 (see FIG. 3) are formed, and the communication between the ports 31b, 31c and 31d is blocked by the land portion 32.
a, the spool 32 being variably controlled by a
The control port 31b always communicates with the discharge port C of the oil pump 20, the control port 31b constantly communicates with the sub suction port A of the oil pump 20, The main port 31d is always in communication with the main suction port B of the oil pump 20. In addition, the accommodation room of the spring 33
It is always in communication with the oil pan 40, and the pressure (spool 3
2 is not generated.

In the control valve 30, the control port 3
A first control mode (see FIG. 1) in which the sub port 31c communicates only with the main port 31d in accordance with the hydraulic pressure (discharge pressure) applied to the sub port 31c, and a sub port 31c in which communication between the sub port 31c and the main port 31d is maintained. And the control port 31b are communicated with each other through the variable throttle unit O1, and the main port 31d and the control port 3 are connected to the sub port 31c.
The second control mode (see FIG. 3) in which the hydraulic oil flows from the sub port 31c and the main port 3 while the communication between the sub port 31c and the control port 31b is maintained.
1d through the variable throttle unit O2 to control port 3
A third control mode (see FIG. 4) in which hydraulic oil flows from 1b to the sub port 31c and the main port 31d;
A fourth control mode (see FIG. 5) in which the subport 31c communicates only with the control port 31b, and the subport 31 with the communication between the subport 31c and the control port 31b maintained.
and the control port 31b
In the fifth control mode (see FIG. 6) in which the hydraulic oil flows through the sub port 31c and the main port 31d from above, the discharge amount characteristic shown in FIG. 7 can be obtained. . In the first control mode, the characteristic between points 0 and a in FIG. 7 is obtained, in the second control mode, the characteristic between points a and b in FIG. 7 is obtained, and in the third control mode, b in FIG. The characteristics between points c and c are obtained, the characteristics between points c and d in FIG. 7 are obtained in the fourth control mode, and the characteristics after point d in FIG. 7 are obtained in the fifth control mode.

In the embodiment constructed as described above, when the rotation speed N of the crankshaft 10 is in the rotation range between 0 and N1, the spool 32 in the control valve 30 is schematically shown in FIG. In this position, the sub port 31c is disconnected from the control port 31b and is maintained in communication with the main port 31d. For this reason, in the oil pump 20, since both the main suction port B and the sub suction port A fully function as suction ports, the hydraulic oil is sufficiently sucked from the main suction port B and the sub suction port A, and in the low rotation region. 7 can be obtained, and the discharge amount characteristics of 0 to a shown in FIG. 7 are obtained, and the discharge amount is pressure-fed to the supply destination section 50 through the discharge path 41.

When the rotational speed N of the crankshaft 10 is in the rotational range between N1 and N2, the spool 32 of the control valve 30 is at a position schematically shown in FIG. In a state where the communication with the port 31d is maintained (the state where the communication with the control port 31b is hardly stopped by the variable throttle unit O2), the communication amount with the control port 31b is variably controlled by the variable throttle unit O1, and the main port is connected to the sub port 31c. Hydraulic oil flows from 31d and the control port 31b. Therefore, in the oil pump 20, a part of the hydraulic oil flowing from the discharge port C to the discharge port flows into the sub suction port A through the control valve 30, and the hydraulic oil flows from the main suction port B to the sub suction port A. Although the main suction port B functions as a suction port after being sucked, the function of the sub suction port A as the suction port is reduced according to the flow rate of the hydraulic oil flowing from the control port 31b through the variable throttle portion O1. A ~ shown in FIG.
As a result, the discharge amount characteristic b can be obtained, and the discharge amount corresponding to the reduced function of the sub suction port A as the suction port can be reduced, so that the pump load can be reduced.

When the rotation speed N of the crankshaft 10 is in the rotation range between N2 and N3, the spool 32 of the control valve 30 is in the position schematically shown in FIG. The amount of communication with the main port 31d is variably controlled by the variable throttle unit O2 in a state where the communication with the port 31b is maintained (the state where the throttle is almost not throttled by the variable throttle unit O1), and the control port 31b is connected to the sub port 31c. And the working oil flows to the main port 31d. For this reason, in the oil pump 20, a part of the hydraulic oil flowing from the discharge port C to the discharge port flows into the sub suction port A and the main suction port B via the control valve 30, and the sub suction port A serves as a suction port. In a state where the main suction port B hardly functions, the function of the main suction port B as the suction port can be reduced according to the flow rate of the hydraulic oil flowing from the control port 31b through the variable throttle portion O2.
To c, the discharge amount for the sub-suction port A not functioning as a suction port and the discharge amount for the reduced function of the main suction port B as a suction port can be reduced, and the pump load can be reduced. Can be achieved.

When the rotational speed N of the crankshaft 10 is in the rotational range between N3 and N4, the spool 32 of the control valve 30 is, for example, in the position schematically shown in FIG. While the communication with the port 31b is maintained and the communication with the main port 31d is shut off, the hydraulic oil flows from the control port 31b to the sub port 31c, but the hydraulic oil flows from the control port 31b to the main port 31d. Not flowing. Therefore, in the oil pump 20, a part of the hydraulic oil flowing from the discharge port C to the discharge port flows into the sub-suction port A through the control valve 30, but does not flow into the main suction port B. In the state where hardly functions as a suction port, the main suction port 21c functions sufficiently as a suction port, so that the discharge amount characteristics of c to d shown in FIG. 7 are obtained, and the sub suction port 21d functions as a suction port. It is possible to reduce the discharge amount by the amount not to be performed, and to reduce the pump load.

When the rotational speed N of the crankshaft 10 is in the rotational range of N4 or more, the spool 32 of the control valve 30 is located, for example, at the position schematically shown in FIG. Is fully open, the amount of communication between the main port 31d and the control port 31b and the sub port 31c is variably controlled, and hydraulic oil flows from the control port 31b to the sub port 31c and the main port 31d. For this reason, in the oil pump 20, a part of the hydraulic oil flowing from the discharge port C to the discharge port flows into the sub suction port A and the main suction port B via the control valve 30, and the sub suction port A serves as a suction port. In a state where the main suction port B hardly functions, the function of the main suction port B as a suction port can be reduced in accordance with the flow rate of the working oil flowing from the control port 31b, so that the discharge amount characteristics after d shown in FIG. The discharge amount corresponding to the sub suction port A not functioning as the suction port and the discharge amount corresponding to the deterioration of the function of the main suction port B as the suction port can be reduced, and the pump load can be reduced.

As is apparent from the above description, in the present embodiment, in the second control mode of the control valve 30, the discharge amount can be reduced by the function of the sub-suction port 21d as the suction port, and the control valve can be reduced. In the third control mode of FIG. 30, the discharge amount by which the sub suction port 21d does not function as the suction port and the discharge amount by the function deterioration of the main suction port 21c as the suction port can be reduced. In the control mode, the sub-suction port 21d does not function as a suction port.
In the fifth control mode, the discharge amount corresponding to the sub suction port 21d not functioning as the suction port and the main suction port 2
It is possible to reduce the discharge amount corresponding to the reduced function as the suction port 1c, and to maximize the reduction of the pump load when the drive source shifts from the low rotation region to the middle / high rotation region and in the middle / high rotation region. The driving power can be reduced to the maximum.

In the present embodiment, the oil pump device comprises a single oil pump 20 having a main suction port B, a sub suction port A, a discharge port C, etc., as shown in FIG. A control valve 30 for controlling a part of the flow of the hydraulic oil discharged from the oil pump 20 to the main suction port B and the sub suction port A in accordance with the pressure of the hydraulic oil discharged from the oil pump 20. Therefore, the oil pump device can be made small, light, and compact, and the mountability of the oil pump device on a vehicle body or the like can be improved.

In the above embodiment, the present invention is applied to an oil pump device driven by a crankshaft 10 of a vehicle engine (internal combustion engine). However, the present invention is applied to an oil pump device used for industrial equipment other than a vehicle. The pump device can be similarly or appropriately modified and implemented, and the type of the oil pump (trochoid type in the above-described embodiment) and the drive mode (direct drive type in the above-described embodiment) can also be appropriately changed.

[Brief description of the drawings]

FIG. 1 is a view schematically showing an embodiment of an oil pump device according to the present invention.

FIG. 2 is a diagram showing a case where both rotors shift in rotation in the oil pump shown in FIG. 1;

FIG. 3 is a cross-sectional view schematically showing a form of a control valve shown in FIG. 1 in a second control mode.

FIG. 4 is a sectional view schematically showing a form of a control valve shown in FIG. 1 in a third control mode.

FIG. 5 is a cross-sectional view schematically showing a form of the control valve shown in FIG. 1 in a fourth control mode.

FIG. 6 is a cross-sectional view schematically showing a form of the control valve shown in FIG. 1 in a fifth control mode.

FIG. 7 is a characteristic diagram showing a relationship between a rotation speed and a discharge amount obtained by the oil pump device shown in FIG.

[Explanation of symbols]

10 ... Engine crankshaft (drive source), 20 ...
Oil pump, 21: pump housing, A: sub suction port, A1: shape of the inner peripheral end of the sub suction port, B: main suction port, B1: shape of the anti-rotational end of the main suction port, C: Discharge port, R: pump chamber (variable volume chamber), R1: end shape of pump chamber in the rotation direction, R2: end of pump chamber in the anti-rotation direction, L: rotation locus of end of pump chamber in the anti-rotation direction, 30 ... Control valve, 31 ... Valve housing, 31a ... Inner hole, 31b ... Control port, 3
1c: Sub port, 31d: Main port, 32: Spool, 32a: Land portion, 33: Spring, 40: Oil pan, 50: Feeding portion.

Claims (2)

[Claims] An oil pump, which is rotationally driven by a drive source, and a control valve capable of circulating a part of hydraulic oil discharged from the oil pump, supplies a predetermined amount of hydraulic oil to a portion to be supplied. In the oil pump device for pressure feeding, as the oil pump, a main suction port which is always in communication with a suction port, a sub suction port which is in communication with and blocked from the main suction port via the control valve, and which is always in communication with a discharge port. A single oil pump having a discharge port and having a plurality of circumferentially formed pump chambers rotationally shifted to sequentially communicate with the sub suction port, the main suction port, and the discharge port is adopted. Then, the shape of the end of the oil pump on the side opposite to the rotation direction in the main suction port is instantaneously sealed between the sub suction port and the main suction port. Along with the shape of the pump chamber in the rotational direction end, the shape of the inner peripheral end of the sub suction port is instantaneously sealed between the sub suction port and the main suction port. An oil pump device characterized in that the pump chamber has a shape along a rotation locus of an end on the opposite side in the rotation direction of the pump chamber. 2. The oil pump device according to claim 1, wherein said pump chamber is a variable volume chamber formed between an inner rotor and an outer rotor which are eccentrically arranged.