JPH0350884B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lubrication device for a two-stroke engine.

[Prior Art] As one type of lubrication system for a two-stroke engine, there is a separate lubrication system that supplies lubricating oil to various parts of the engine using an oil pump from a system separate from the fuel.

Here, conventionally, as the above-mentioned lubricating device, a pump lever connected to a discharge amount adjusting section of an oil pump driven by rotation of a crankshaft and a throttle lever connected to a throttle valve shaft are linked together. However, a lubricating device is used in which the discharge amount of an oil pump is varied according to changes in the opening degree of a throttle valve. In the oil pump in this lubricating device, although its discharge amount increases as the opening degree of the throttle valve increases, the range of change, that is, the maximum discharge amount is constant.

[Problems to be Solved by the Invention] By the way, two-stroke engines have different oil requirements depending on their specifications, so it is difficult to use an oil pump with a constant maximum discharge amount for two-stroke engines of various specifications. cannot be applied. Therefore, in the conventional lubricating device described above, it is necessary to use oil pumps of various capacities with different maximum discharge amounts for two-stroke engines of various specifications.

The present invention makes it possible to adjust the range of change in the oil pump discharge amount according to changes in the opening degree of the throttle valve, and makes it possible to apply an oil pump of the same capacity to two-stroke engines of various specifications. The purpose is to provide a lubricating device for

[Means for Solving the Problems] The present invention provides a pump lever connected to a discharge amount adjustment section of an oil pump driven by rotation of a crankshaft, and a throttle lever connected to a throttle valve shaft. In a 2-stroke engine lubricating system that links and connects the oil pump and changes the oil pump's discharge amount according to changes in the opening of the throttle valve, the oil pump's discharge amount is increased with less than the return torque of the throttle valve. A biasing torque directed in the direction is constantly applied to the pump lever, and in the rotation range of the throttle valve from the closed position to the intermediate opening, the throttle lever is interlocked with the throttle valve shaft, and the throttle valve moves to the intermediate opening. The throttle lever is connected to the throttle valve shaft so that the throttle valve shaft moves idly relative to the throttle lever in a rotation range exceeding It is.

[Operation] Until the throttle valve shaft reaches a predetermined intermediate opening corresponding to the maximum operating angle of the throttle lever, the throttle lever and pump lever are rotated by the biasing torque of the pump lever, and the oil is Increase pump output. When the throttle valve shaft exceeds the above intermediate opening degree, the throttle lever and pump lever, which are linked together, do not rotate because the maximum operating angle of the pump lever is biased, and only the throttle valve shaft rotates, and there is no increase in discharge amount. Therefore, by adjusting the maximum operating angle of the pump lever, it is possible to adjust the upper limit of the increase range of the oil pump discharge amount, making it possible to apply the same capacity oil pump to two-stroke engines of various specifications. becomes possible.

[Embodiment] Fig. 1 is a front view showing a 2-stroke, 3-cylinder outboard engine to which an embodiment of the present invention is applied, and Fig. 2 shows an oil pump used in the embodiment. FIG.

Three cylinders are formed in the cylinder block 11 vertically. A vertical crankshaft 13 is rotatably supported between the cylinder block 11 and the crankcase 12. A drive shaft 13A disposed within the propulsion unit is connected. A piston 14 is housed in each cylinder, and each piston 14 is connected to the crankshaft 13 via a connecting rod 15. A carburetor 18 is connected to the crank chamber 16 of each cylinder via an intake manifold 17. In addition, 19 in the figure
is an oil tank that stores lubricating oil.

An oil pump 20 is fixed to the front lower part of the cylinder block 11. oil pump 20
As shown in FIG. 2, the oil tank 19 is connected to a suction pipe 21 and a discharge pipe 2 corresponding to each cylinder.
2, and a driven gear 2 that meshes with a drive gear 24 fixed to the crankshaft 13.
5, a ring gear 26 that meshes with the driven gear 25,
A revolving body 28 that forms an oil chamber 27 that communicates intermittently with the suction pipe 21 and the discharge pipe 22, and is integrated with the ring gear 26 and rotatably supported by the housing 23; A plunger 29 is housed and reciprocates up and down within the oil chamber 27, a spring 30 urges the plunger 29 downward, and a spring 30 is fixed to the housing 23 so that the tip of the pin 31 of the plunger 29 can be pushed upward. It has a cam 32 that That is, when the rotating body 28 rotates within the housing 23 through the meshing of the driving gear 24 and the driven gear 25 and the driven gear 25 and the ring gear 26 as the crankshaft 13 rotates, the rotating body 28 rotates as well. The plunger 29 performs a pumping action by moving up and down within the oil chamber 27 through contact between its pin 31 and cam 32, and pumps the oil tank through a suction hose 33 connected to the suction pipe 21. The lubricating oil sucked from 19 is transferred from each discharge pipe 22 to each discharge hose 34, 3.
5, 36, the intake manifold 1 of each cylinder
7 and can be discharged into the air-fuel mixture.

Furthermore, the oil pump 20 includes a ring gear 26.
an adjustment plate 37 that is vertically movably inserted into the inner periphery of the adjustment plate 37, a spring 38 that biases the adjustment plate 37 downward, and a pin 39 that is integrated with the adjustment plate 37.
It has an adjustment cam 40 that pushes the tip of the cam upward. The adjustment plate 37 has its upper surface abutted against the lower surface of the plunger 29 to regulate the lower end position of the plunger 29, thereby regulating the reciprocating stroke of the plunger 29, thereby increasing the maximum discharge of the oil pump 20. The amount can be regulated. Here, an adjustment cam 40 protruding from the housing 23
A pump lever 42 is fixed to the camshaft 41 of
A throttle lever 45 is coupled to the pump lever 42 via a link 43 and is connected to a throttle valve shaft 44 . That is, as the opening degree of the throttle valve increases, the operating angle θ _B of the pump lever 42 and adjustment cam 40 increases via the throttle lever 45 and link 43, and the adjustment plate 37 moves further downward. The reciprocating stroke of the plunger 29 increases, and the discharge amount Q of the oil pump 20 can be increased as shown in FIG. 3.

Here, as shown in FIG. 4, the oil pump 2
0 housing 23 and the pump lever 42, the return spring torque T A of the throttle valve interposed between the throttle valve shaft 44 and the carburetor body is smaller than the return spring torque T _A of the oil pump 20. A spring 46 is interposed that allows a biasing torque T _B to be applied to the pump lever 42 in the direction of increasing the amount. Further, a notch 4 is provided at the connecting portion of the throttle lever 45 to the throttle valve shaft 44.
7 is formed, and the throttle valve shaft 44 and throttle lever 45 are arranged within a predetermined angle range (θ _A2 +α).
It is said that relative rotation is possible within. In addition, in the figure, 47A is the throttle valve shaft 44 that comes into contact with it,
The return spring torque _TA of the throttle valve is a pushing surface that acts on the throttle lever 45. Also,
The carburetor body is provided with an adjustment screw 48 that comes into contact with the side of the throttle lever 45 and allows the maximum operating angle θ _A1 of the throttle lever 45 to be adjusted. The adjusting screw 48 may be screwed onto the throttle lever side and may come into contact with the carburetor body.

Note that the adjustment screw 48 is connected to the throttle lever 45.
The maximum operating angle of the pump lever 42 is adjusted via the link 43. In the present invention, the maximum operating angle of the pump lever 42 may be directly adjusted.

Next, the operation of the above embodiment will be explained. When the throttle valve shaft 44 rotates from the closed position to an intermediate opening corresponding to the maximum operating angle θ _A1 of the throttle lever 45, the biasing torque T _B of the spring 46 causes the throttle to open as shown in FIG. Lever 4
5 rotates to its maximum operating angle θ _A1 , and the pump lever 42 rotates to its maximum operating angle K. That is, the throttle lever 45 is always applied with torque in the clockwise direction in FIG. A counterclockwise torque in FIG. 4 is always applied by the biasing torque. Therefore, when the throttle valve shaft 44 is rotated in the opening direction (counterclockwise direction) by the driver's throttle operation force, the throttle lever 45 and the pump lever 42
They are driven together by the torque caused by the spring 46. When the throttle valve shaft 44 rotates between the above-mentioned intermediate opening and a fully open position that is the sum of the operating angle θ _A2 following the intermediate opening, only the throttle valve shaft 44 is rotated through the notch 47.
The maximum operating angles K and θ _A1 of the pump lever 42 and the throttle lever 45 are maintained by the biasing torque T _B of the spring 46 . In addition,
The notch 47 provided in the throttle lever 45 allows the throttle valve shaft 44 to be further relatively rotated by an angle α after the throttle valve shaft 44 has been relatively rotated by the angle θ _A2 . This α is a margin angle for ensuring that the throttle valve shaft 44 can always be rotated to the fully open position even if there are variations in component dimensions. That is, the maximum discharge amount of the oil pump 20 is _QK , which corresponds to the maximum operating angle K of the pump lever 42 in this case, as shown in FIG. By changing the maximum operating angle K of the oil pump 20, it becomes possible to adjust the upper limit of the maximum discharge amount _QK of the oil pump 20.
Note that when the throttle valve shaft 44 is closed from the maximum operating angle θ _A1 of the throttle lever 45 to the fully closed position side, the throttle valve return spring torque _TA is applied to the throttle via the pushing surface 47A. Since the valve shaft 44 acts on the throttle lever 45, the pump lever 42 and the throttle lever 45 can be returned to their closed positions by the return spring torque _TA .

That is, according to the above embodiment, the adjustment screw 48
By the adjustment operation, it becomes possible to adjust the upper limit of the range of increase in the discharge amount of the oil pump 20, and adjust the maximum discharge amount of the oil pump 20 of the same capacity.
It becomes possible to apply this to outboard motors with different specifications.

In addition, in the above embodiment, the pump lever 4
2. Since a biasing torque is always applied in the direction of increasing the discharge amount of the oil pump 20, even if the torque 43 is dropped or play increases due to wear of link joints, the oil pump The discharge amount of the oil pump 20 is adjusted in the direction of maximum increase by the return torque, so that seizing or the like due to insufficient oil supply does not occur.

Further, in the above embodiment, the pump lever 42
By changing the lever ratio between the throttle lever 45 and the throttle lever 45, the operating angle change rate of the pump lever 42 with respect to the throttle valve opening changes as shown by the two-dot chain line in FIG. It becomes possible to adjust the oil discharge amount depending on the opening degree.

[Effects of the Invention] As described above, according to the present invention, it is possible to adjust the range of change in the oil pump discharge amount according to the change in the opening degree of the throttle valve, and it is possible to adjust the range of change in the oil pump discharge amount according to the change in the opening degree of the throttle valve. Can be applied to cycle engines.

[Brief explanation of drawings]

FIG. 1 is a front view showing a two-stroke three-cylinder engine for an outboard motor to which an embodiment of the present invention is applied;
Fig. 2 is a sectional view showing the oil pump used in the same example, Fig. 3 is a diagram showing the discharge characteristics of the oil pump, and Fig. 4 is an enlarged view showing the main parts of Fig. 1. , FIG. 5 is a diagram showing the operating angle relationship between the pump lever and the throttle lever in the same embodiment. 13... crankshaft, 18... carburetor, 20...
...Oil pump, 29...Plunger, 37...
Adjustment plate, 40... Adjustment cam, 42... Pump lever, 43... Link, 44... Throttle valve shaft, 45... Throttle lever, 46... Spring,
T _A : Return torque, T _B : Biasing torque.

Claims (1)

[Claims] 1. A pump lever connected to the discharge amount adjusting section of an oil pump driven by the rotation of the crankshaft and a throttle lever connected to the throttle valve shaft are linked together, and the opening degree of the throttle valve can be changed. In a two-stroke engine lubricating system that varies the oil pump's discharge amount according to The throttle lever is interlocked with the throttle valve shaft in the rotation range of the throttle valve from the closed position to the intermediate opening position.
The throttle lever is connected to the throttle valve shaft so that the throttle valve shaft moves idly relative to the throttle lever in the rotation range where the throttle valve exceeds the above intermediate opening, and the maximum operating angle of the pump lever is adjusted. A 2-cycle engine lubrication device characterized by being adjustable.