JPH04272415A - Lublicating device of engine for vehicle - Google Patents

Abstract

PURPOSE:To reduce a lubricating oil supplying amount at the time of a low load operation while improving lubricating property at the time of rapid deceleration by providing the reciprocating motion mechanism and the stroke adjusting means of a plunger on an oil pump for oiling separately which is provided on a two cycle engine. CONSTITUTION:The plunger 20 of an oil pump 18 is contained slidably in a pump case 21 and rotatably around an axial center while connected to a crank shaft by a worm gear device 22. At this time, a reciprocating motion mechanism is provided on one end of the plunger 20, and it consists of a cylindrical cam 23 formed coaxially on the one end of the plunger 20 and a rotary shaft 24 which is provided rotatably around the center of an axis which is perpendicular to the plunger 20 of the pump case 21. A stroke adjusting means is provided on the plunger 20, and it consists of a stroke adjusting projection 38 provided on the center position of the cylindrical cam 23 on the one end of the plunger 20 and a stroke adjusting cam 39 provided eccentrically to the axial center of the rotary shaft 24.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubrication system for a vehicle engine that appropriately supplies lubricating oil to a two-stroke engine using a separate oil pump.

0003

2. Description of the Related Art Two-stroke engines mounted on motorcycles and the like are often equipped with a separate oil supply type lubrication system. As shown in FIG. 7, such a lubricating device includes an oil pump 2 installed in an engine 1.
As a result of this operation, lubricating oil from the oil tank 3 is supplied to, for example, the intake passage 4 of the engine 1 to lubricate the inside of the engine 1. Note that numeral 5 indicates a carburetor.

The oil pump 2 is, for example, a plunger-type constant displacement oil pump, and discharges lubricating oil by the reciprocating motion of a plunger (not shown). Some oil pumps 2 are provided with a stroke adjustment lever 6, as also shown in FIG. This stroke adjustment lever 6 is connected to stroke adjustment means (not shown) that adjusts the stroke of the reciprocating motion of the plunger. Furthermore, this stroke adjustment lever 6 is
It is connected to a throttle cable 8 via a stroke adjustment cable 7, as shown in FIG.

Therefore, when the opening degree of the throttle valve of the carburetor 5 is changed by operating the throttle grip 9 via the throttle cable 8, the throttle adjustment lever 6 rotates in response to the change in the opening degree, and the above-mentioned stroke adjustment is performed. The stroke amount of the plunger is changed through means. In other words, as shown in FIG. 9, when the throttle valve opening is large, the operating angle of the throttle adjustment lever 6 becomes large, the stroke of the oil pump plunger becomes large, and the amount of lubricating oil discharged from the oil pump increases. do. Furthermore, when the throttle valve opening is small, the operating angle of the throttle adjustment lever 6 becomes small, the throat talk of the plunger becomes small, and the amount of lubricating oil from the oil pump 2 decreases.

[0006]

[Problems to be Solved by the Invention] Among the above, when the throttle valve opening is fully closed, the operating angle of the stroke adjustment lever 6 becomes the minimum, and the stopper portion 10 of the stroke adjustment lever 6 reaches the stopper 11. Therefore, the stroke of the plunger of the oil pump is also minimized, and the amount of oil discharged is reduced. When the throttle valve is fully closed in this way, there are two cases: during low-load operation such as when the engine is idling, and when the throttle valve is suddenly fully closed when the engine is running at high speeds to cause sudden deceleration. The amount of lubricating oil in both of these cases is determined by the stopper portion 10 of the stroke adjustment lever 6 coming into contact with the stopper 11.

However, the engine speed differs between idling and sudden deceleration from high engine speed, and therefore the required amount of lubricating oil also differs. For this reason, if the amount of lubricating oil is determined based on idling, insufficient lubrication is likely to occur during sudden deceleration from high engine speed. Furthermore, if the amount of lubricating oil is determined in accordance with the sudden deceleration from high engine speed, the amount of lubricating oil may become excessive during low-load operation (for example, when idling), and white smoke may be produced.

The present invention has been made in consideration of the above-mentioned circumstances, and has an object to reduce the amount of lubricating oil supplied during low-load engine operation, and to also improve the lubrication performance during sudden deceleration from high engine speed. The purpose of the present invention is to provide a lubrication device for a vehicle engine that can perform the following steps. [Structure of the invention]

[0009]

[Means for Solving the Problems] The present invention provides a lubricating system for a vehicle engine in which lubricating oil is supplied to each part of the engine by a separate oil pump installed in a two-stroke engine, wherein the oil pump is a pump. A plunger rotatably driven by the engine is built into the case, and one end of the plunger is provided with a pump chamber and a discharge port and a suction port communicating with the pump chamber,
A plunger reciprocating mechanism for reciprocating the plunger according to the rotation of the plunger is installed at the other end, and a stroke adjusting means for adjusting the stroke amount of the plunger is installed near the plunger reciprocating mechanism. means is connected to a throttle cable via a stroke adjustment lever disposed on the pump case, a stopper portion of the throttle adjustment lever contacts an eccentric cam, and the eccentric cam rotates in accordance with the engine speed. It is configured such that the contact position with the stopper portion can be changed.

0010

[Operation] The throttle adjusting means is connected to the throttle cable and changes the stroke of the plunger depending on the opening degree of the throttle valve, thereby changing the amount of lubricating oil discharged from the oil pump. Therefore, when the throttle valve is fully closed, the stopper portion of the stroke adjustment lever hits the eccentric cam, and the stroke of the plunger is reduced by the operation of the stroke adjustment means.

During no-load operation such as when the engine is idling, the throttle valve is fully closed, but the engine speed is also low, so the stopper part of the stroke adjustment lever is moved to the eccentric cam's low engine speed setting position. comes into contact with. Therefore, the stroke adjusting means adjusts the stroke of the plunger to be the minimum, thereby reducing the amount of lubricating oil discharged from the oil pump.

On the other hand, when the engine speed is high, if the opening of the throttle valve is suddenly fully closed and the engine is suddenly decelerated, the eccentric cam is being rotated even though the throttle valve is fully closed because the engine speed is high. The stopper portion of the adjustment lever comes into contact with the high rotation setting position of the eccentric cam. Therefore, the stroke adjustment means connected to the stroke adjustment lever acts so that the stroke amount of the plunger does not become the minimum. As a result, when the engine suddenly decelerates from a high speed, the oil pump can supply the required amount of lubricating oil to the engine, and the lubrication performance in this case can be improved.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

FIG. 2 is a schematic view showing an embodiment of a vehicle engine lubricating system according to the present invention, and FIG. 1 is a side view showing the oil pump of FIG. 2 with the throttle fully closed variable cam lever removed.

As shown in FIG. 2, a two-stroke engine 1
2 includes a crankcase 13, a cylinder 14, an intake passage 15 communicating with the crankcase 13, and an exhaust passage 16 communicating with the cylinder 14.
A carburetor 17 is disposed at. This two-stroke engine 12 includes an oil pump 18 and an oil tank 19.
The lubricating oil in the oil tank 19 is guided to the oil pump 18 via the suction hose 33, and
A separate oil supply type lubricating device is provided which supplies oil to the intake passage 15 of the engine 12 through the engine 12.

The oil pump 18 is a plunger type constant displacement oil pump driven by a crankshaft within the crankcase 13. This oil pump 1
The plunger 20 of No. 8 is, as shown in FIGS. 3 and 4,
It is built into the pump case 21 so as to be slidable in the axial direction and rotatable around the axis. The plunger 20 is connected to the crankshaft by a worm gear device 22, and rotates about its axis as the crankshaft rotates.

A plunger reciprocating mechanism is installed at one end of the plunger 20. In other words, this plunger reciprocating mechanism includes a cylindrical cam 23 coaxially formed on one end of the plunger 20 and a cylindrical cam 23 disposed in the pump case 21 so as to be rotatable around an axis perpendicular to the plunger 20. and a rotation shaft 24. Cylindrical cam 2
3 has peaks 23a and valleys 23b alternately formed in the circumferential direction. This cylindrical cam 23 is elastically brought into sliding contact with the outer circumferential surface of the rotating shaft 24 by the biasing force of a spring 29 disposed at the other end of the plunger 20 .

Therefore, when the plunger 20 is rotated by the crankshaft via the worm gear device 22, the peaks 23a and troughs 23b of the cylindrical cam 23 alternately come into sliding contact with the outer peripheral surface of the rotation shaft 24, and the plunger 20
moves back and forth in its axial direction.

A pump chamber 26 is formed at the other end of the plunger 20, and a suction port 27 and a discharge port 28 are formed in communication with the pump chamber 26. A rod 29 is accommodated within the pump chamber 26, and the rod 29 is fixed to a cap 30 covering the other end of the pump case 21. Due to the presence of the rod 29, the pump chamber 26 can accommodate the plunger 2.
Due to the reciprocating motion of 0, its volume changes in size.

On the other hand, the pump case 21 is provided with a suction pipe 31 and a discharge pipe 32, each of which is shown in FIG.
A suction hose 33 and a discharge hose 34 shown in are connected. The suction pipe 31 communicates with a mechanism chamber 24A that houses the cylindrical cam 23 and the rotating shaft 24 shown in FIG. At the time, the suction port 2 of the plunger 20
7 and guides lubricating oil to the pump chamber 26. Also,
The discharge pipe 32 communicates with a discharge passage 36 formed in the pump case 21, and this discharge passage 36 connects to the pump chamber 26.
When the volume is small, it communicates with the discharge port 28.

Therefore, when the volume of the pump chamber 26 increases due to the reciprocating movement of the plunger 20, the oil pump 18
A suction hose 33 for lubricating oil from the oil tank 19;
The lubricating oil in the pump chamber 26 is sucked into the pump chamber 26 through the discharge pipe 31, the suction passage 35, and the suction port 27, and when the volume of the pump chamber 26 is small, the lubricating oil in the pump chamber 26 is transferred to the discharge port 28 and the discharge passage 36.
The lubricating oil is led to a discharge hose 32 through a discharge pipe 32 and discharged into the intake passage 15 of the engine 12 to lubricate each part of the engine 12. Note that when the oil pump 18 is in operation, the lubricating oil from the oil tank 19 lubricates the cylindrical cam 23 and the rotating shaft 24, and
The worm gear device 22 is also lubricated via a lubrication passage 37 communicating with the suction passage 35.

The oil pump 18 is equipped with a stroke adjustment means that adjusts the stroke amount of the reciprocating motion of the plunger 20 to change the amount of oil discharged by the oil pump 18 for each stroke. . This stroke adjustment means is integrally formed with a stroke adjustment protrusion 38 provided at the center of the cylindrical cam 23 on one end surface of the plunger 20 and the rotation shaft 24.
Stroke adjustment cam 3 provided eccentrically with respect to the axis of
9. A stroke adjustment lever 40 is bolted to the rotation shaft 24. A stroke adjustment cable 41 is engaged with this stroke adjustment lever 40 as shown in FIGS. 1 and 2, and this stroke adjustment cable 41 is connected to a throttle cable 43 connected to a throttle grip 42.

Therefore, when the throttle grip 42 is operated to change the opening degree of the throttle valve (not shown) of the carburetor 17 via the throttle cable 43,
According to this throttle valve opening degree, the rotation shaft 24 and the stroke adjustment cam 39 shown in FIGS. 3 and 4 rotate via the throttle adjustment cable 41 and the throttle adjustment lever 40. The stroke adjustment cam 39 and the stroke adjustment protrusion 38 are arranged so that when the rotation shaft 24 rotates, the stroke adjustment protrusion 38 moves to the stroke adjustment cam 39 before the valley portion 23b of the cylindrical cam 23 comes into sliding contact with the outer peripheral surface of the rotation shaft 24. is formed so as to come into contact with the outer circumferential surface of. As a result,
By rotating the rotation shaft 24 in accordance with the throttle valve opening degree, the contact position of the stroke adjustment protrusion 38 with respect to the stroke adjustment cam 39 is selected, and thereby the stroke amount of the plunger 20 is adjusted in accordance with the throttle valve opening degree. The amount of lubricating oil discharged from the oil pump 18 is changed.

When the throttle valve is fully closed, the stroke adjustment lever 40 is rotated in the direction of arrow A by operating the stroke adjustment cable 41, as shown in FIG. The amount of lubricating oil discharged from the oil pump 18 by contacting the variable cam 45 is reduced. This throttle full-close variable cam 45 is formed in an eccentric cam shape, and as shown in FIGS. 2 and 4, the throttle full-close variable cam lever 4
6. This throttle full-close variable cam lever 46 is connected to a servo motor 48 via a throttle full-close variable cable 47.
is controlled by a control unit 49.

The servo motor 48 is also connected to an exhaust valve 50 of the exhaust device via a valve operation cable 51. The exhaust valve 50 improves engine output by, for example, advancing the exhaust timing in a high engine speed range and delaying the exhaust timing in a low engine speed range. The control unit 49 detects the engine rotation speed, controls the drive of the servo motor 48, operates the exhaust valve 50, and
Rotate the throttle fully closed variable cam lever 46.

The rotation of the throttle fully closed variable cam lever 46 causes the throttle fully closed variable cam 45 to rotate. This throttle fully closed variable cam 45 is controlled by the control unit 49 so that it rotates in the direction of arrow B in FIG. 1 when the engine speed increases, and rotates in the direction opposite to arrow B when the engine speed decreases. The radius of the throttle fully closed variable cam 45 is formed to gradually increase in the direction opposite to arrow B. Therefore, when the engine speed increases, the stopper portion 40 of the stroke adjustment lever 40
A rotates in the opposite direction to arrow A even when the throttle valve is fully closed. As a result, the stroke adjustment cam 39 shown in FIG. 3 rotates in conjunction with the stroke adjustment lever 40, and the contact position with the stroke adjustment protrusion 38 changes, causing the engine to rotate even when the throttle valve is fully closed. As the number increases, the stroke amount of the plunger 20 of the oil pump 18 is increased. Therefore, even when the throttle valve is fully closed, when the engine speed is high, the amount of lubricating oil discharged from the oil pump 18 is controlled to increase.

That is, as shown in FIGS. 1 and 6, when the throttle valve is fully closed, the engine speed is approximately 50.
Until the speed exceeds 00 rpm, press the stroke adjustment lever 40.
The stopper portion 40a of the throttle fully closed variable cam 45 is
contact the position. The engine rotation speed exceeds about 5000 rpm to about 7000 rpm, exceeds about 7000 rpm,
When the speed reaches approximately 9,000 rpm and exceeds approximately 9,000 rpm, the stopper portion 4 of the stroke adjustment lever 40
0a comes into contact with positions b, c, and d of the throttle fully closed variable cam 45, respectively, when the throttle valve is fully closed. The operating angle of the throttle adjustment lever 40 when the stopper part 40a of the throttle adjustment lever 40 comes into contact with each position a, b, c, and d of the throttle fully closed variable cam 45 is expressed as θa,
Assuming that θb, θc, and θd, when the throttle valve is fully closed, the amount of lubricating oil discharged from the oil pump 18 is Qa when the operating angle of the throttle adjustment lever 40 is θa, and similarly, the operating angle of the stroke adjustment lever 40 is θb. ,θ
c, θd, the lubricating oil discharge amounts from the oil pump 18 are Qb, Qc, Qd (Qa<Qb<Qc<
Qd).

As described above, the stroke adjustment lever 40 and the throttle fully closed variable cam 45 are arranged so that the amount of lubricating oil discharged from the oil pump 18 when the throttle valve is fully closed increases as the engine speed increases. Since the engine speed is low during no-load operation such as idling, the amount of lubricating oil discharged from the oil pump 18 can be reduced, and the generation of white smoke can be prevented. Further, since the engine speed is high during sudden deceleration when the throttle valve is fully closed from a high engine speed range, the amount of lubricating oil discharged from the oil pump 18 is large, and the engine 12 can be suitably lubricated.

Furthermore, since the operating angle of the stroke adjustment lever 40 when the throttle valve is fully closed is changed by the throttle fully closed variable cam 45, the amount of lubricating oil discharged when the throttle valve is fully closed can be accurately adjusted according to the engine speed. can be controlled.

In the above embodiment, the fully closed throttle variable cam lever 46 is operated by the servo motor 48 in conjunction with the exhaust valve 50 of the exhaust device.
6 and the exhaust valve 50 may be controlled by separate servo motors and control units. Further, as shown in FIG. 6, in the above embodiment, the throttle fully closed variable cam 45 is changed stepwise for each arbitrary region of the engine speed. It may be made to change continuously according to the number.

[0031]

As described above, according to the vehicle engine lubricating device according to the present invention, the oil pump for separate oil supply installed in a two-stroke engine has a plunger rotatably driven by the engine in the pump case. built-in,
A pump chamber and a discharge port and a suction port communicating with the pump chamber are provided at one end of the plunger, and a plunger reciprocating mechanism for reciprocating the plunger according to rotation of the plunger is installed at the other end. A stroke adjustment means for adjusting the stroke amount of the plunger is installed near the plunger reciprocating mechanism, and this stroke adjustment means is connected to a throttle cable via a stroke adjustment lever disposed on the pump case, and the stroke adjustment means The stopper part of the lever comes into contact with an eccentric cam, and this eccentric cam rotates according to the engine speed to change the contact position with the stopper part, which improves lubrication during low-load engine operation. Not only can the amount of oil supplied be reduced, but also the lubrication performance of the engine during sudden deceleration from a high engine speed range can be improved.

[Brief explanation of the drawing]

FIG. 1 is a side view of the oil pump shown in FIG. 2 with the throttle fully closed variable cam lever removed.

FIG. 2 is a schematic diagram showing an embodiment of a vehicle engine lubrication device according to the present invention.

FIG. 3 is a longitudinal sectional view showing the oil pump of FIG. 1.

FIG. 4 is a sectional view taken along line IV-IV in FIG. 3;

FIG. 5 is a graph showing the relationship between the oil discharge amount and the operating angle of the throttle adjustment lever in the oil pump of FIG. 1;

FIG. 6 is a graph showing the relationship between the position of the fully closed throttle variable cam and the engine speed in the oil pump of FIG. 1;

FIG. 7 is a schematic diagram showing a conventional vehicle engine lubrication system.

8 is a side view showing the oil pump of FIG. 7. FIG.

9 is a graph showing the relationship between the oil discharge amount and the operating angle of the stroke adjustment lever in the oil pump of FIG. 8. FIG.

[Explanation of symbols]

12 2-cycle engine 17 Carburetor 18 Oil pump 19 Oil tank 20 Plunger 21 Pump case 23 Cylindrical cam 24 Rotating cam 25 Spring 26 Pump chamber 27 Suction port 28 Discharge port 38 Stroke adjustment protrusion 39 Stroke adjustment cam 40 Stroke adjustment lever 40a Stroke adjustment Lever stopper part 41
Stroke adjustment cable 43 Throttle cable 45 Throttle fully closed variable cam 46 Throttle fully closed variable cam lever 47 Throttle fully closed variable cable 48 Servo motor

Claims (1)

[Claims] 1. A vehicle engine lubricating device in which lubricating oil is supplied to each part of the engine by a separate oil pump installed in a two-cycle engine, wherein the oil pump is mounted in a pump case and is rotatably driven by the engine. A plunger is built in, one end of the plunger is provided with a pump chamber, a discharge port and a suction port communicating with the pump chamber, and the other end is provided with a plunger reciprocating mechanism for reciprocating the plunger according to rotation of the plunger. A stroke adjusting means for adjusting the stroke amount of the plunger is installed near the plunger reciprocating mechanism, and the stroke adjusting means is connected to the throttle cable via a stroke adjusting lever disposed on the pump case. The stopper portion of the throttle adjustment lever contacts the eccentric cam, and the eccentric cam rotates in accordance with the engine speed to change the position of contact with the stopper portion. A lubricating device for vehicle engines.