JPH10184483A - Pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the man-hour of processing works of a pump mounting apparatus side reduce the number of seal devices arranged by efficiently interconnecting a passage formed on the pump mounting apparatus side with a plurality of passages on the pump body side without increasing the number of passages formed on the pump mounting apparatus side. SOLUTION: AN annular groove 40 on the suction side and an annular groove 41 on the discharge side are formed in the outer peripheral surface of a pump body 10, fitted in the mounting hole 17 of a cylinder head cover 16, in a state to be axially separated away from each other. One end of a bypass passage 45 and a suction passage 44 are opened to the annular groove 40 on the suction side. The other end of the bypass passage 45 and a discharge passage 47 are opened to the annular groove 41 on the discharge side. Check valves 48 and 49 are located in the suction passage 44 and the discharge passage 47 and a relief valve 50 is located in the bypass passage 45. The annular groove 40 on the suction side and the annular groove 41 on the discharge side are communicated with a suction passage 42 and a discharge passage 43 on the cylinder head cover 16 side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump device used for an oil pump or the like of an automobile, and more particularly to a pump device having a pump body mounted on the pump mounting device and having a passage on the pump mounting device side through a fitting surface thereof. The present invention relates to a pump device in which a passage on a pump body side is connected and connected.

[0002]

2. Description of the Related Art In recent years, as a fuel pressurizing pump for a fuel injection device of an automobile, a pump body is fitted and fixed in a mounting hole provided in a cylinder head cover of an engine, and a plunger housed in the pump body is camshaft of the engine. It has been devised to be driven by (for example,
JP-A-8-14140, etc.). Since this fuel pressurizing pump directly fits and fixes the valve body to the cylinder head cover portion of the engine as the pump mounting device, there is no need to provide a dedicated housing for covering the cam drive unit. The size and weight can be reduced.

In view of the above-mentioned advantages, this type of pump device in which a valve body is directly fitted to and fixed to a mounting device is currently employed, for example, in an auxiliary oil pump for a variable valve operating device of an engine. Is desired.

[0004]

However, when a pump device of the above-mentioned type is used for an auxiliary oil pump or the like, a suction passage and a discharge passage formed on a pump mounting device (engine) side and a pump body side. And a plurality of passages such as a suction passage, a discharge passage, and a relief passage (bypass passage) must be connected through a fitting surface on the outer periphery of the pump body. For this reason, a plurality of passages corresponding to the number of passages on the pump body side and the opening position thereof must be branched and formed on the pump mounting device side, and the number of sealing devices corresponding to the number of connection passages must be provided. Instead, the number of processing steps and the number of parts on the pump mounting device side increase, resulting in an increase in manufacturing cost.

[0005] Therefore, the present invention allows the passage on the pump mounting device side and the plurality of passages on the pump body side to be efficiently connected without increasing the number of passages formed on the pump mounting device side and the number of sealing devices. Accordingly, it is an object of the present invention to provide a pump device capable of reducing the manufacturing cost.

[0006]

According to the present invention, as a means for solving the above-mentioned problem, a pump body fitted in a mounting hole of a pump mounting device is provided with a suction passage and a discharge passage communicating with a pump working chamber. A bypass passage that bypasses the pump working chamber is provided, and in a state where the pump body is fitted in the mounting hole, the suction passage and one end of the bypass passage are attached to the pump through a fitting surface on an outer periphery of the pump body. In the pump device, which is connected to a suction passage of a device and the other end of the discharge passage and the bypass passage are connected to a discharge passage of a pump mounting device, the suction passage is provided on a fitting surface on an outer periphery of the pump body. A suction-side annular groove that opens at one end of the bypass passage, and a discharge-side annular groove that opens at the discharge passage and the other end of the bypass passage are formed axially separated from each other. The annular groove And so as to communicate respectively with the suction passage and the discharge passage of the pump mounting equipment. The suction passage and the discharge passage of the pump mounting device only need to communicate with the suction-side annular groove and the discharge-side annular groove of the pump body, respectively. It is only necessary to form them one by one. Further, since the number of passages on the pump mounting device side is reduced, the number of sealing devices for preventing fluid leakage can be reduced.

A check valve may be interposed in each of the suction path and the discharge path. Further, the bypass passage may be provided with a relief valve that opens when the pressure in the discharge passage becomes higher than the pressure in the suction passage by a set pressure or more. There may be more than one.

Further, a seal ring may be attached before and after each axial direction of the suction-side annular groove and the discharge-side annular groove. In such a case, leakage of fluid can be reliably prevented by a simple structure having a small number of parts.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

In the drawings, reference numeral 1 denotes a pump device according to the present invention. The pump device 1 of this embodiment includes a first pump mechanism 1A functioning as a fuel pressurizing pump of a fuel injection device, and a variable valve operating device. And a second pump mechanism 1B functioning as an auxiliary oil pump.
As shown in FIG. 1, a first pump mechanism 1A has a motor-driven supply pump 2 connected to its suction side via a low-pressure regulator 3 and a discharge side connected to an injector 4 of a fuel injection device. The fuel sent from the fuel tank 5 through the supply pump 2 is pressurized to a set high pressure and then supplied to the injector 4. Also,
The second pump mechanism 1B has an engine-driven main oil pump 6 connected to its suction side, and a discharge side connected to an actuator 8 of a variable valve operating device via a switching valve 7. The engine oil sent from the oil pan 9 through the oil pump 6 is pressurized to a set pressure and then supplied to the actuator 8 side.

The pump body 10 of the pump device 1 has
Suction pipe connection port 11 of fuel system (fuel injection device side circuit)
Substantially rectangular body base 1 provided with a discharge pipe connection port 12
The plug 3 has a generally cylindrical plug portion 14 extending therefrom, and a thin cylindrical plunger guide portion 15 extending from the tip of the plug portion 14 to have a general shape. The pump body 10 is configured such that the plug portion 14 is fitted into a mounting hole 17 formed in a cylinder head cover 16 of the engine from the outside of the engine, and the body base 13 is fixed to the cylinder head cover 16 by bolts 18 in this state. Has become. When the pump body 10 is thus attached to the cylinder head cover 16, the tip of the plunger guide 15 faces the outer peripheral surface of the pump cam 19. The pump cam 19 is provided coaxially with a camshaft 20 of the engine, and has cam lobes 19 on its outer peripheral surface corresponding to the number of cylinders of the engine.
a (four cam peaks in this embodiment).

The pump body 10 is formed with an assembling hole 21 which forms the inner peripheral surfaces of the plunger guide portion 15 and the plug portion 14. A cylindrical cylinder 22 is screwed into the assembling hole 21. A rod-shaped first plunger 23 is slidably fitted into the cylinder 22. The space between the bottom surface of the assembling hole 21 in the cylinder 22 and the upper end surface of the first plunger 23 constitutes a first pump working chamber 24. It is designed to act as a pump. The first pump working chamber 24 is formed between the suction pipe connection port 11 and the discharge pipe connection port 1 by a substantially T-shaped communication passage 25 formed in the body base 13.
The suction passage 26 is provided with a suction check valve 26 and a discharge check valve 27 at the end of the communication passage 25 on the suction pipe connection port 11 side and the end of the communication passage 25 on the discharge pipe connection port 12 side. .

The body base 13 is provided with a solenoid type pressure regulating valve 28 for adjusting the pressure in the fuel system discharge pipe. The pressure regulating valve 28 includes a poppet 29 driven by a solenoid, and a return passage 30 communicating the discharge pipe connection port 12 and the suction pipe connection port 11.
The amount of throttling of a to 30 g is appropriately controlled by the poppet 29, thereby adjusting the amount of fuel returned from the return passages 30 a to 30 g to maintain the pressure in the discharge pipe at a desired pressure. Return passage 30a-3
A passage 30f downstream of the pressure-regulating valve 28 of 0 g is formed in an annular shape between the cylinder 22 and the assembling hole 21. The annular passage 30f is provided via a communication passage 31 formed in the cylinder 22. Thus, it communicates with an annular fuel reservoir 32 formed between the cylinder 22 and the first plunger 23. The fuel reservoir 32 is a portion that captures high-pressure fuel that has flowed into the gap between the cylinder 22 and the first plunger 23 from the first pump working chamber 24, and maintains this portion at a low pressure (the pressure of the low-pressure regulator 3). The fuel is prevented from leaking outside the cylinder 22 through the gap between the cylinder 22 and the first plunger 23.

On the other hand, a spring seat 33 is fixed to the lower end of the first plunger 23. A second cylindrical plunger 34 having a bottom is fitted into the spring seat 33, and the lower end surface of the first plunger 23 is closed. The upper surface of the second plunger 34 is in contact with the center. The second plunger 34 is provided with the plunger guide 1.
5, and in this state, the second pump working chamber 35 is constituted by a space defined by the cylinder 22 and the mounting hole 21. Also, cylinder 2
An annular step 36 is formed in the lower part 2 so that the outer diameter of the lower half is small. The first plunger 23 and the second plunger 34 are disposed between the step 36 and the spring seat 33. Spring 3 biasing toward pump cam 19
7 are interposed. A circular concave portion 38 is formed on the lower surface of the second plunger 34, and a circular wear-resistant material 39 that directly contacts the outer peripheral surface of the pump cam 19 is accommodated in the concave portion 38. Therefore, the second plunger 34 is always in contact with the outer peripheral surface of the pump cam 19 via the wear-resistant material 39, and the first plunger 23 and the second plunger 34 advance and retreat according to the profile of the pump cam 19.

By the way, the plug portion 1 of the pump body 10
A suction-side annular groove 40 and a discharge-side annular groove 41 are formed on the outer peripheral surface (fitting surface) of the cylinder body 4 in the axial direction so as to be separated from each other. The grooves 40 and 41 communicate with the suction passage 42 and the discharge passage 43 on the cylinder head cover 16 side, respectively. A suction passage 44 communicating with the second pump working chamber 35 is formed in the suction side annular groove 40, and one end of each of first and second bypass passages 45 and 46 bypassing the second pump working chamber 35 is formed in the suction side annular groove 40. The discharge side annular groove 41 is formed with an opening, and a discharge path 47 communicating with the second pump operating chamber 35 is formed in the discharge side annular groove 41, and the other ends of the first and second bypass paths 45 and 46 are opened. Is formed.

The suction passage 44 is provided with a suction check valve 48 for allowing oil to flow from the suction side annular groove 40 toward the second pump working chamber 35.
7 is provided with a discharge check 49 that allows oil to flow from the second pump working chamber 35 in the direction of the discharge side annular groove 41. In addition, the first bypass passage 45 includes the discharge passage 4
A relief valve 50 that opens the bypass passage 45 when the pressure in the discharge passage 3 (discharge-side annular groove 41) becomes higher than the pressure in the suction passage 42 (suction-side annular groove 40) by a set pressure or more is provided. The second bypass passage 46 is provided with a communication valve 51 that opens the bypass passage 46 when the pressure (absolute pressure) in the suction passage 42 (suction-side annular groove 40) exceeds a set pressure. .

The relief 50 valve has a structure in which a spherical valve body 52 is urged by a spring 53 from the suction side annular groove 40 side to be seated on a valve seat 54 formed directly on the pump body 10. When the pressure in the side annular groove 41 becomes higher than the pressure in the suction side annular groove 40 by a set pressure or more, the force due to the pressure difference is opposed to the force of the spring 53 and the valve body 52
From the valve seat 54, thereby returning a part of the oil in the discharge passage 43 to the suction passage 42 side.
Decrease the pressure inside.

As shown in FIG. 3, the second bypass passage 46 has a spool chamber 55 extending in the axial direction of the pump body 10, and a suction side annular groove 40 and a discharge side at upper and lower sides of the side wall of the spool chamber 55. The suction port 56 and the discharge port 57 communicate with the annular groove 41, respectively.
A spool 59 having a stopper projection 58 at one end;
Atmospheric pressure chamber 6 provided at the other end of spool 59
0 and a spring 61 for urging the spool 59 toward the suction port 56 so that the stopper projection 58 contacts the end face of the spool chamber 55. In the figure, 62
Is an introduction port for introducing atmospheric pressure into the atmospheric pressure chamber 60. The communication valve 51 is configured such that when the pressure of the oil acting on the end face of the spool 59 through the suction port 56 becomes higher than the set pressure, the side wall of the spool 59 is closed in the initial state. Is displaced against the force of the spring 61 to open the discharge port 57, whereby the suction side annular groove 40 and the discharge side annular groove 4 are opened.
1 is turned on to stop substantial pumping in the second pump working chamber 35.

Furthermore, seal rings 63, 64, 65 are disposed before and after each axial direction of the suction side annular groove 40 and the discharge side annular groove 41 of the pump body 10, and these seal rings 63, 64, 65 are provided. 65, each annular groove 40, 4
1 to prevent oil from leaking.

In the above arrangement, when the camshaft 20 rotates with the start of the engine, and the pump cam 19 provided coaxially with the camshaft 20 rotates, the first and second plungers 23 and 34 rotate the cam of the pump cam 19. Mountain 19
It is pushed up by a so that the forward / backward operation is continuously performed.

At this time, in the first pump mechanism 1A, when the first plunger 23 descends, the suction check valve 26 opens to suck the fuel sent from the supply pump 2 into the first pump working chamber 24. First plunger 2
The fuel is pressurized to a high pressure by the ascending operation of 3, and the discharge check valve 27 is opened to supply the pressurized fuel to the injector 4 of the fuel injection device. At this time, the throttle amount of the return passages 30 a to 30 g communicating the discharge pipe connection port 12 and the suction pipe connection port 11 is appropriately controlled by the pressure regulating valve 28, whereby the fuel pressure supplied to the injector 4 is adjusted.

On the other hand, in the second pump mechanism 1B,
When the second plunger 34 descends, the suction check valve 4
8 is opened and the main oil pump 6 moves from the suction side annular groove 40
The engine oil sent to the second plunger 3 is sucked into the second pump working chamber 35 through the suction passage 44,
The oil is pressurized by the ascending operation of 4, the discharge check valve 49 is opened, and the oil is supplied to the actuator 8 side of the variable valve apparatus via the discharge path 47 and the discharge side annular groove 41.

[0023] Here, since the second pump mechanism 1B is a pump structure of the plunger type, as compared to the rise of the discharge pressure of main oil pump 6 (see linear P ₁ in FIG. 9), a relatively large discharge it can be obtained a rise in pressure (see a straight line P ₂ in FIG. 9). Therefore, a sufficient discharge pressure can be supplied to the actuator 8 of the variable valve operating device even at the beginning of the engine, and as a result, the variable valve operating device can be operated as desired even at the beginning of the engine. It becomes possible. When the difference between the discharge pressure of the second pump mechanism 1B and the discharge pressure of the main oil pump 6 reaches the set pressure as the engine speed increases (point B in FIG. 9), the relief valve 50 is activated. By opening the first bypass passage 45, the oil in the discharge-side annular groove 41 is returned to the suction-side annular groove 40, and the subsequent rise of the discharge pressure is suppressed. Then, when the engine speed further increases and the pressure in the suction-side annular groove 40 reaches the set pressure (point A in FIG. 9), the communication valve 51 at this time connects the second bypass passage 46.
To release the oil from the suction-side annular groove 40 to the discharge-side annular groove 4.
1 to stop the actual operation of the second pump mechanism 1B. Therefore, when the engine speed further increases thereafter, a discharge pressure only by the operation of the main oil pump 6 is introduced to the actuator 8 side thereafter.

In the meantime, in the case of the pump device 1, on the outer periphery of the plug portion 14 of the pump body 10, one end of each of the first and second bypass passages 45 and 46 and the suction side annular groove 40 in which the suction passage 44 is opened, The other end of each of the first and second bypass passages 45 and 46 and the discharge-side annular groove 41 in which the discharge passage 47 opens are formed in the axial direction so as to be separated from each other. On the other hand, the suction side annular groove 40
And the discharge side annular groove 41, the suction side and the discharge side passages are formed on the cylinder head cover 16 side one by one from any direction toward the corresponding annular groove. Only good. Therefore, in this pump device 1, it is possible to reduce the number of processing steps on the cylinder head cover 16 side to reduce the manufacturing cost, and to form a plurality of passages on the pump body 10 side at arbitrary circumferential positions. Because it can be done, the degree of freedom of passage layout increases.

Further, in the case of this pump device 1,
Since the seal rings 63, 64, and 65 are disposed before and after the suction-side annular groove 40 and the discharge-side annular groove 41 in the axial direction, the peripheral area of each connection part on the suction side and the discharge side is simplified in structure. Sealing can be performed efficiently with very few sealing parts. Therefore, it is possible to reduce the manufacturing cost from this aspect as well.

The embodiments of the present invention are not limited to those described above. For example, the pump device may have only one pump mechanism, and the pump device may be applied. It may be other than the auxiliary oil pump of the variable valve device.

[0027]

As described above, according to the present invention, the suction side annular groove in which one end of the suction passage and one end of the bypass passage are opened, and the discharge passage and the other end of the bypass passage are formed on the fitting surface on the outer periphery of the pump body. The discharge-side annular groove that is opened is formed to be spaced apart in the axial direction, and the suction-side annular groove and the discharge-side annular groove communicate with the suction passage and the discharge passage of the pump mounting device. It suffices to form only one suction passage and one discharge passage from the arbitrary directions toward the corresponding annular grooves, respectively.As a result, the number of processing steps on the pump mounting device side and the number of sealing devices to be installed are reduced. It is possible to reduce the manufacturing cost by reducing the number. In addition, since the passages formed on the pump body side, such as the suction passage, the discharge passage, and the bypass passage, can be arranged at arbitrary positions in the circumferential direction, there is an advantage that the degree of freedom in the layout of the passages in the pump body is increased. . Further, since the suction-side annular groove and the discharge-side annular groove are formed on the outer peripheral surface of the pump body, the processing thereof is extremely easy, and the manufacturing cost can be reduced in this respect as well.

Further, in the case where the seal rings are attached before and after each of the suction side annular groove and the discharge side annular groove in the axial direction, the leakage of the fluid is reliably prevented by a simple structure having a small number of parts. And the manufacturing cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing the embodiment.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 1 showing the embodiment.

FIG. 4 is a sectional view of the same embodiment, taken along line BB of FIG. 1;

FIG. 5 is a sectional view of the embodiment, taken along the line CC in FIG. 4;

FIG. 6 is an exemplary sectional view taken along the line DD of FIG. 1 showing the embodiment;

FIG. 7 is a sectional view of the embodiment, taken along line EE of FIG. 1;

FIG. 8 is a hydraulic circuit diagram showing the embodiment.

FIG. 9 is a diagram showing pressure-rotation speed characteristics of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pump device, 10 ... Pump body, 16 ... Cylinder head cover (pump mounting equipment), 17 ... Mounting hole, 35 ... 2nd pump working chamber (pump working chamber), 40 ... Suction side annular groove, 41 ... Discharge side annular Groove, 42: suction passage, 43: discharge passage, 44: suction passage, 45: first bypass passage (bypass passage), 46: second bypass passage (bypass passage), 47: discharge passage, 48: suction check valve ( Check valve), 49: Discharge check valve (check valve), 50: Relief valve, 63-65: Seal ring.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshio Okubo 1370 Onna, Atsugi-shi, Kanagawa Prefecture Inside Unisia Gex Co., Ltd. 72) Inventor Hirokazu Akiba 1370 Onna, Atsugi-shi, Kanagawa Prefecture Inside Unisia Gex Co., Ltd. (72) Inventor Kimio Tomita 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Nissan Motor Co., Ltd. Nissan Motor Co., Ltd. (72) Inventor Yoshihiro Okada, Kanagawa-ku, Yokohama-shi Nissan Motor Co., Ltd. (72) Nissan Motor Co., Ltd. (72) Inventor Naoki Yamamoto, Nagoya 2 Automobile Co., Ltd.

Claims (5)

[Claims] A pump body fitted in a mounting hole of a pump mounting device is provided with a suction path and a discharge path communicating with a pump working chamber and a bypass path bypassing the pump working chamber. The suction passage and one end of the bypass passage are connected to the suction passage of the pump mounting device through the fitting surface on the outer periphery of the pump body in a state where the suction passage is fitted to the mounting hole, and the other ends of the discharge passage and the bypass passage are connected to each other. A pump device having an end connected to a discharge passage of a pump mounting device, wherein a suction-side annular groove in which an end of the suction passage and one end of a bypass passage are opened on a fitting surface on an outer periphery of the pump body; A discharge-side annular groove that is open at the other end of the bypass passage is formed axially separated, and the suction-side annular groove and the discharge-side annular groove communicate with the suction passage and the discharge passage of the pump mounting device, respectively. Nishiko Pump device according to claim. 2. The pump device according to claim 1, wherein a check valve is provided in each of the suction path and the discharge path. 3. A relief valve that opens when the pressure in the discharge passage becomes higher than the pressure in the suction passage by a predetermined pressure or more is provided in the bypass passage.
Or the pump device according to 2. 4. The pump device according to claim 1, wherein a plurality of said bypass paths are provided. 5. The pump device according to claim 1, wherein a seal ring is mounted before and after each of the suction side annular groove and the discharge side annular groove in the axial direction.