JPH11247757A - Reversible oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To be used even for high viscous oil at a low temperature. SOLUTION: A cylinder 2 is rotatably arranged in a pump body 1, and a worm wheel 4, which engages a driving worm 6, is integrally formed in the plunger 3, which is provided so as to freely get in and out the pump room 2a of the cylinder 2, and a discharge quantity setting cam 5, which abuts on the lead cam 4a provided in the worm wheel 4, is turnably provided in the pump body 1, and a discharge passage 2b and a suction passage, which are communicated with the pump room 2a and open in the peripheral face of a cylinder, are provided in the cylinder 2, and a discharge hole 1a and suction hole are provided in the pump body 1, and the lead cam 4a and the discharge quantity setting cam 5 are pressed against each other by a spring 7, and the cylinder is pressed against a lid 9 through a retainer 8 to make the recessed section of the worm wheel 4 and the projection of the cylinder engage with each other with play, and a plurality of radially extending legs abutting on the lid 9 and an angle section having a peak at the center are formed in the retainer 8, and the legs are fitted in the recessed section provided in the cylinder, and the peak is made to abut on the end face of the cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separated lubricating oil pump for supplying lubricating oil to automobiles, motorcycles, snowmobiles, etc., and more particularly to a reversible oil pump suitable for snowmobiles.

[0002]

2. Description of the Related Art A lubricating oil pump using a rotation of an engine as a pump drive source and applicable to a small two-cycle engine such as a golf cart without a back gear is proposed in Japanese Utility Model Publication No. 61-23668. Have been.

[0003] The reversible rotary oil pump proposed in Japanese Utility Model Publication No. 61-23668 discloses the insertion of a plunger whose axial position is immovable into a cylinder that rotates while reciprocating a stroke set by a discharge amount setting cam. A worm wheel that communicates with a pump chamber and communicates with a suction port and a discharge port provided in a pump body through a suction and discharge path that is opened on a cylinder peripheral surface during a suction stroke and a discharge stroke, respectively, and the cylinder rotates while reciprocating. With 180 ° play.

When the worm wheel rotates in any direction, the suction / discharge path communicates with the suction hole during the suction stroke, and the suction / discharge path communicates with the discharge hole during the discharge stroke. That is, the pump is reversible. However, since this reversible oil pump reciprocates a cylinder having a large diameter, the cylinder becomes difficult to move when the oil viscosity is high at a low temperature, and there is a problem that it is not suitable for a low-temperature use type such as a snowmobile.

FIGS. 4 to 6 show examples of a conventional oil pump of a type in which the axial position of a cylinder is fixed and a plunger reciprocates. FIG. 4 is a cross-sectional view showing the oil pump. A pump body 1 shown in FIG. 4 is provided with a cylindrical space into which a cylinder 2 is fitted and an oil chamber 1b connected thereto, and these spaces are tightened with screws 12. It is separated from the outside by a lid 9 and a flange 10.

[0006] Oil is supplied through a nipple 11 integrated with the flange 10, and the oil is discharged from the discharge ports 1a, 1a. As shown in detail in FIG.
And a pump chamber 2a into which the plunger 3 shown in FIG. 6 (b) is fitted.
b and the suction passage 2c communicate with the peripheral surface of the plunger 3.

The plunger 3 fitted into the pump chamber 2a of the cylinder 2 is pressed into the worm wheel 4, as shown in FIG. A lead cam 4a is provided on the right end surface of the worm wheel 4, and protrusions 4b, 4
b is provided. In the drawing, the lead cam 4a is 1
Although only one is visible, two are provided symmetrically with respect to the central axis.

A driving worm 6 to which the rotation of the engine is transmitted is rotatably provided in the oil chamber 1b of the pump body 1, and a discharge amount setting cam 5 is rotatably provided. A compression coil spring 7 interposed between the cylinder 2 and the worm wheel 4 presses the lead cam 4 a against the discharge amount setting cam 5 and presses the retainer 13 fitted on the cylinder 2 against the lid 9. As shown in FIG. 6, the retainer 13 is in surface contact with the cylinder 2 due to the flange flat surface 13 a contacting the cylinder 2.
3b is in contact and is in point contact.

As shown in FIG. 5C, concave portions 2e and 2e are formed between the convex portions 2d and 2d on the right end surface of the cylinder 2, and the convex portions 4b of the worm wheel 4 are formed in the concave portions 2e and 2e. , 4b are fitted. The cylinder 2 is urged leftward by the compression coil spring 7 and the retainer 13 fitted to the cylinder 2 is kept pressed against the lid 9, and the axial position of the cylinder 2 does not move.

The pump body 1 includes a discharge passage 2 for a cylinder 2.
Discharge ports 1a, 1a are provided at 180 ° intervals at positions where b opens. The suction ports provided at 180 ° intervals at positions displaced from the discharge port 1a in the axial direction communicate with the oil chamber 1b. These suction ports and their communication paths are shown in FIG.
And is not shown.

In the above configuration, when the worm wheel 4 is rotated by the driving worm 6, the lead cam 4a of the worm wheel 4 comes into sliding contact with the discharge amount setting cam, and the plunger 2 integrated with the worm wheel 4 rotates in the axial direction per rotation. Make two round trips.

The cylinder 2 does not move in the axial direction, but rotates in synchronization with the worm wheel 4, and in the suction stroke in which the plunger 2 moves rightward, the suction passage 2c communicates with the suction port of the pump body. The discharge passage 2b communicates with the discharge port 1a of the pump body in the discharge stroke moving leftward.
The two discharge ports 1a and 1a supply an equal amount of oil to different oil supply ports.

The above-described oil pump can be used for low-temperature and high-viscosity oil because the large-diameter cylinder 2 only rotates and does not move in the axial direction. When rotated in the direction, the suction passage 2c communicates with the discharge port 1a of the pump body during the suction stroke, and the discharge passage 2b communicates with the suction port of the pump body during the discharge stroke.

There is play in the engagement between the concave portion of the cylinder 2 and the convex portion of the worm wheel 4, and the communication timing between the discharge passage 2b and the discharge opening 1a and between the suction passage 2c and the suction opening is adjusted by bidirectional rotation. However, since the contact between the retainer 13 and the lid 9 is a point contact at the center, the frictional resistance against the rotation of the cylinder 2 is small, and the compression coil spring 7 is provided between the worm wheel 4 and the cylinder 2. Since the frictional force generated by the pressing force acts, the cylinder 2
Can rotate in synchronism with the worm wheel 4 at an intermediate position of the play of the connection with the worm wheel 4, so that the communication timing between the discharge passage 2b and the discharge port 1a and the communication between the suction passage 2c and the suction port can be synchronized. Did not. That is, there has been no reversible rotary oil pump which has a variable discharge amount and can be used for oil having a high viscosity at a low temperature.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to be applicable to oils which have a variable discharge rate and a high viscosity at low temperatures. It is to provide a reversing oil pump.

[0016]

A reversible rotary oil pump according to the present invention comprises a cylinder rotatably disposed in a cylindrical space provided in a pump body, and a driving worm mounted on a plunger provided in a pump chamber of the cylinder so as to be able to move in and out. A meshing worm wheel is integrally formed, and a discharge amount setting cam that comes into contact with a lead cam provided on the worm wheel is displaceably provided on the pump body, and a suction discharge passage communicating with the pump chamber and opening on the cylinder peripheral surface is provided. A discharge hole and a suction hole are provided in the cylinder, the discharge hole and the suction hole having the same position as the opening of the suction / discharge passage in the cylinder axial direction, and the lead cam and the discharge amount are provided by a spring interposed between the worm wheel and the cylinder. The setting cam is pressed against the cylinder, and the cylinder is pressed against a lid closing the cylindrical space via a retainer. In a reversible rotary oil pump in which a projection provided on one of end faces of a wheel and the cylinder facing each other and a recess provided on the other are engaged with play, a plurality of radially extending oils contact the retainer with the lid. A leg and a chevron having an apex at the center are formed, the leg is fitted into a concave portion provided in the cylinder, and the apex is brought into contact with an end face of the cylinder.

Further, in the reversible rotary oil pump,
The driving worm and the discharge amount setting cam are arranged in an oil suction passage communicating with the suction hole.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A reversible rotary oil pump according to an embodiment of the present invention will be described below with reference to FIGS.
In FIG. 6, the portions having the same functions as those shown in FIGS. 4 to 6 are denoted by the same reference numerals, and the overlapping description will be omitted.

In the reversible rotary oil pump of the embodiment, FIG.
As shown in FIG. 3C, the concave portion 2e engaging with the convex portion 4b (shown in FIG. 3C) of the worm wheel 4 of the cylinder 2 has an angle α, and the convex portion 4b of the worm wheel 4 is The two recesses 2e engage with play.

Further, as shown in FIG.
The legs 8a, 8a,... Extending radially and a chevron having a vertex 8b at the center are formed, and the flat surfaces 8c, 8c,. Abuts the end face of The legs 8a, 8a,.
(D) are fitted into recesses 2f, 2f... Of the end face of the cylinder 2.

When the cylinder 2 rotates, the retainer 8 also rotates integrally with the cylinder 2, and the flat surfaces 8c, 8c,. A large frictional resistance is generated in the sliding contact portion, and the cylinder 2 rotates together with the worm wheel 4 in a state where the side surface of the concave portion 2e and the side surface of the convex portion 4b of the worm wheel 4 are in contact. That is, the communication timing between the discharge passage 2b and the discharge port 1a and the communication between the suction passage 2c and the suction port can be adjusted by bidirectional rotation.

The cylinder 2 is made of a material having good cutting properties in order to machine the small-diameter discharge passage 2b and the like. Although such a material has low wear resistance, the use of a wear-resistant material for the retainer 9 that generates frictional resistance between the lid 9 prevents the life from being shortened due to wear.

Since the retainer 9 pushes the cylinder 2 at the central apex 8b, only the axial force is applied to the cylinder 2 so that no one-sided contact occurs between the cylinder 2 and the pump body 1, and No vibration occurs even if 2 rotates at high speed. When the retainer 9 and the cylinder 2 are brought into surface contact with each other or in contact with the cylinder 2 at a plurality of places other than the center, when the processing accuracy of the retainer 9 and the cylinder 2 is poor, a force other than the axial direction is applied to the cylinder 2 so that the high-speed rotation It starts to vibrate.

The stroke of the plunger 3 can be varied by the rotational position of the discharge amount setting cam 5. For example, by interlocking the discharge amount setting cam 5 and the valve shaft of the throttle valve, the oil corresponding to the output of the engine can be adjusted. A quantity can be supplied to the engine.

The embodiment is configured as described above.
The invention is not limited to this. For example, the discharge amount setting cam may be displaced in the axial direction.

[0026]

According to the reversible rotary oil pump of the present invention,
Sufficient oil can be supplied even when used in a low-temperature environment such as a snowmobile, and there is no back gear, and the rotation of the engine can be used as a drive source even when the engine is rotated reversely. .

[Brief description of the drawings]

FIG. 1 is a sectional view showing a reversible rotary oil pump according to an embodiment of the present invention.

FIG. 2 (a) is a front view showing a cylinder of the reversible rotary oil pump, and FIG. 2 (b) is an AA in FIG. 2 (a).
FIG. 2 (c) is a right side view showing the same cylinder, and FIG.
(D) is a left side view showing the cylinder.

3 (a) is a bottom view showing a retainer of the reversible oil pump, FIG. 3 (b) is a side view showing the retainer, FIG.
FIG. 3C is a sectional view showing an assembly of a plunger and a worm wheel of the reversible rotary oil pump.

FIG. 4 is a sectional view showing an example of a conventional oil pump.

5 (a) is a front view showing a cylinder of the oil pump, FIG. 5 (b) is a sectional view taken along line BB in FIG. 5 (a), and FIG. 5 (c) is a right side view showing the cylinder FIG.

6 (a) is a side view showing a retainer of the oil pump, and FIG. 6 (b) is a sectional view showing an assembly of a plunger and a worm wheel of the oil pump.

[Explanation of symbols]

Reference Signs List 1 pump body, 1a discharge port, 1b oil chamber 2 cylinder, 2a pump chamber, 2b discharge passage, 2c
Suction passage, 2d convex portion, 2e concave portion, 2f concave portion 3 plunger, 4 worm wheel, 4a lead cam, 4b protrusion 5 discharge amount setting cam 6 driving worm 7 compression coil spring 8 retainer, 8a leg, 8b vertex, 8c flat surface 9 lid 10 Flange 11 Nipple 12 Screw 13 Retainer, 13a Flange plane, 13b Apex

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hisanori Ito 309, Toyama, Takizawa-mura, Takizawa-mura, Iwate-gun Iwate Prefecture Inside of Miknia Deck Co., Ltd.

Claims (2)

[Claims] A worm wheel meshing with a driving worm is formed integrally with a plunger rotatably provided in and out of a pump chamber of the cylinder. A discharge amount setting cam which comes into contact with a lead cam provided on the pump body is displaceably provided on the pump body, a suction discharge passage communicating with the pump chamber and opening on the cylinder peripheral surface is provided on the cylinder, and an opening of the suction discharge passage and the cylinder are provided. A discharge hole and a suction hole whose axial positions match each other are provided in the pump body, and the lead cam and the discharge amount setting cam are pressed against each other by a spring interposed between the worm wheel and the cylinder, and the cylinder is connected via a retainer. One of the end faces where the worm wheel and the cylinder face each other by pressing against the lid closing the cylindrical space. A reversible rotary oil pump in which the projection provided on the other side and the recess provided on the other side are engaged with play, wherein the retainer includes a plurality of radially extending legs abutting on the lid and a chevron having a vertex at the center. The reversible rotary oil pump is formed, wherein the leg is fitted in a concave portion provided in the cylinder, and the apex is brought into contact with an end surface of the cylinder. 2. The reversible oil pump according to claim 1, wherein the driving worm and the discharge amount setting cam are arranged in an oil suction passage communicating with the suction hole.