JPH0629535B2 - Separated lubrication device for 2-cycle engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separate oil supply device for a two-cycle engine that supplies oil from an oil tank to an engine by means of an oil pump.

[Prior Art] Generally, in this type of two-cycle engine, a plunger-type oil pump driven by a crankshaft is used to forcibly supply lubricating oil to each part of the engine.

The oil discharge amount of the oil pump is determined by the stroke amount of the plunger, and when this stroke amount is controlled according to the throttle opening, that is, the load, if the load is constant, the oil supply amount to the engine speed is almost It is constant.

Therefore, there is a tendency for the amount of oil to become insufficient, especially in the high rotation range. If you try to compensate for this lack of oil,
The amount of oil discharged in the low rotation range becomes excessive, and the amount of oil consumption and the generation of white smoke generally increase.

Conventionally, in order to improve this, a cam formed on the axial end surface of the plunger, and a rotating member having a cam surface on the outer periphery thereof for slidingly contacting the cam and setting the stroke of the plunger, are provided. It is known that the rotating member is rotated by a predetermined angle in association with the load and the rotational speed of the engine to control the stroke amount of the plunger and change the oil discharge amount (Japanese Patent Laid-Open No. 60- 93106).

According to this conventional device, the stroke amount of the plunger is controlled and the oil discharge amount is changed in association with the load and the rotational speed of the engine. The rotating member of the oil pump is connected to the slott set on the handle of the vehicle through a cable to control the slot opening.

[Problems to be Solved by the Invention]

In this way, in the method of controlling the oil discharge amount of the oil pump via the cable for controlling the throttle opening that is led to the outside of the oil pump, the time-dependent change of the cable and the interlock adjustment depending on the driver's preference can be performed. It is easily affected by changes such as repairs.

Therefore, in the above-described conventional device, the oil discharge amount becomes more than necessary or less than necessary, which causes generation of white smoke, adhesion of carbon on the inner wall of the combustion chamber, and deterioration of reliability of lubrication.

In addition, conventionally, when the throttle opening is fully opened during sudden acceleration, the plunger stroke of the oil pump is maximized even if the engine speed is low, and more oil than necessary is supplied to the engine, causing white smoke and the like. In order to prevent this, there is known a cable in which an elastic member or a damper is interposed to delay the throttle opening (see Japanese Patent Laid-Open No. 58-18724).

However, even in this case, the cable, the elastic member, the damper, and the like are susceptible to fluctuations with time.

On the other hand, there are the following methods for controlling the oil discharge amount of the oil pump without the above-described cable for controlling the throttle opening.

That is, the cam that contacts the axial end surface of the plunger of the oil pump is connected to the pressure responsive diaphragm, and this diaphragm is connected to the exhaust pipe of the engine.
It is known that the stroke amount of the plunger is controlled and the oil discharge amount is changed in response to the pressure change in the exhaust pipe, that is, the load of the engine (see Japanese Patent Laid-Open No. 52-84336).

However, according to this conventional device, the pressure change in the exhaust pipe does not necessarily adapt to the load on the engine. Therefore, when the throttle opening is fully opened during sudden acceleration, the plunger stroke of the oil pump is low despite the low engine speed. Is the maximum and more oil is supplied to the engine than is necessary, producing white smoke.

Further, conventionally, it is known that a check valve is provided at the discharge port of oil discharged by a plunger of an oil pump, and when the predetermined engine speed is reached, the check valve is opened to change the oil discharge amount. (See JP-A-49-64735).

However, according to this conventional device, since the oil discharge amount changes abruptly at a predetermined engine speed, more oil than necessary is supplied to the engine at the time of the change, and white smoke or the like is generated.

The present invention has been made to improve the above-mentioned conventional problems, and supplies oil to the engine at an amount of oil that is close to ideal, to prevent generation of white smoke and to prevent carbon from adhering to the inner wall of the combustion chamber. An object is to provide a highly reliable two-cycle engine separated oil supply device.

[Means for Solving the Problems]

A two-cycle engine separated oil supply device according to the present invention is
The ideal amount of oil supply during steady operation with the throttle valve fully open is set in correspondence with the engine speed, and the amount of oil discharged from the oil pump is adjusted based on the change in the engine speed. A separate refueling device for a two-cycle engine in which a predetermined response delay is set for the change in the oil discharge amount with respect to the engine speed, the engine being provided in a pump case. A rotation speed detector, a plunger pump that reciprocates in the axial direction while rotating by the drive of the engine, and an oil discharge amount is set by the stroke of the reciprocating motion and the rotation speed of the plunger; It operates in conjunction with the rotation speed detector and changes the stroke of the plunger pump to change the oil discharge amount to a throttle valve. And a discharge amount adjuster that corresponds to an ideal oil supply amount during steady operation when fully opened, the discharge amount adjuster slidingly contacting the cam formed on the end face in the axial direction of the plunger and the cam. It is composed of a pin body having a slanted surface portion for setting the stroke of the plunger formed on the outer periphery thereof, and the rotation speed detector uses an input shaft driven by the rotation of the engine and a centrifugal force accompanying the rotation of the input shaft. It is characterized by comprising a moving body that moves to move the pin body in the axial direction.

[Action]

According to the above configuration, the oil pump is controlled only by the reciprocating stroke of the plunger and the rotation speed of the engine, and the discharge amount adjuster and the rotation speed detector of the oil pump are connected via the pin body and the moving body. Since they are in contact with each other, the amount of oil supply can be controlled in the oil pump without the need for a cable for controlling the throttle opening as in the conventional case, and the structure is compact.

Moreover, it is possible to supply oil with an amount of oil that is close to the ideal amount for the engine, prevent generation of white smoke and adhesion of carbon on the inner wall of the combustion chamber, and improve reliability of lubrication.

The rotation speed detector includes a moving body that moves in the axial direction by the centrifugal force that accompanies the rotation of the input shaft that is driven by the rotation of the engine, and moves the pin body in the axial direction. Has a predetermined response delay.

Therefore, there is no risk that the oil discharge amount will change suddenly at a predetermined engine speed, and at the time of that change, it will be possible to effectively prevent more than necessary oil from being supplied to the engine and generating white smoke or the like. be able to.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a piston, 2 is a crank chamber, 8 is an intake pipe, 8a is a reed valve, 4 is a carburetor, 5 is an oil tank, 6 is an oil pump, 7 is an oil intake passage, 8 is an oil discharge passage. Is. This two-cycle engine is a separate refueling system and mixes oil with a mixture of fuel and air introduced from the carburetor 4 to the intake pipe 8 to form a mixture,
This is introduced into the crank chamber 2. The oil is discharged from the oil tank 5 into the intake pipe 8 via the oil suction passage 7, the oil pump 6 and the oil discharge passage 8.

FIG. 2 shows the engine speed (hereinafter referred to as the speed N).
V ₁ is the ideal oil supply amount of the engine, and is the minimum necessary amount to be supplied to the inside of the engine when the engine is continuously operated with the throttle valve (not shown) fully open. Shows the amount of oil supply. Here, the steady operation refers to the operation of the engine in which the throttle opening and the engine speed are constant. Similarly, V ₂ shows the ideal amount of oil supply when the throttle opening is 1/2, and V ₄ shows the ideal amount of oil supply when the throttle opening is 1/4. Further, Vi represents the oil discharge amount when the conventional throttle valve is at the idling opening, and Vf represents the oil discharge amount when the conventional throttle valve is fully opened.

According to the method of the present invention, the ideal oil supply amount V ₁ set for the rotation speed N is set in correspondence with the oil discharge amount from the oil pump 6 (see FIG. 1) based on the change in the rotation speed N. It changes. Here, to make the oil discharge amount correspond to the ideal oil supply amount V ₁ means the oil discharge amount discharged from the oil pump 6 (see FIG. 1) and the oil amount actually supplied into the combustion chamber of the engine. A difference or the like may be taken into consideration, and the oil discharge amount is not necessarily made to match the ideal oil supply amount V ₁ . Also, for example, as described below,
In the low speed range, the oil discharge amount may be controlled in linear proportion to only the rotation speed N. By the way, for example, when the oil discharge amount is made equal to the ideal oil supply amount V ₁ , the required oil amount is rapidly reduced when the throttle is fully decelerated at high speed, whereas the method of the present invention is used after the deceleration operation. Also, since it only gradually decreases along the curve of the ideal oil supply amount V ₁ corresponding to the rotation speed N, it is possible that the oil discharge amount becomes excessive. However, in practice, since the air-fuel mixture entering the crank chamber 2 (see FIG. 1) is decelerated, the oil having a relatively large specific gravity in the air-fuel mixture is separated and the crank chamber accumulates. The amount of oil entering the combustion chamber is reduced by that much, and excess oil is suppressed. According to the experiments conducted by the inventors, the pooled oil is used as the oil pump 6
When the amount of oil discharged from (see FIG. 1) is large, it is as high as 80%.

On the other hand, at the time of sudden acceleration, on the contrary, the oil discharge amount may be insufficient. However, since a certain amount of oil is normally accumulated in the crank chamber 2 of FIG. 1, the air-fuel mixture in the crank chamber 2 is accelerated at the time of sudden acceleration, so that it is already accumulated in the crank chamber 2. Since the oil is sucked into the mixture and enters the combustion chamber, the oil shortage is suppressed.

By the way, the conventional oil discharge amount Vf in FIG. 2 is simply proportional to the rotational speed N. On the other hand, according to the present invention, the oil discharge amount is made to correspond to the ideal oil supply amount V ₁ , so that the waste of oil is prevented when the throttle opening is fully opened. Therefore, white smoke during sudden acceleration is greatly reduced.

Further, since the oil discharge amount is made to correspond to the ideal oil amount V ₁ by the number of revolutions N, that is, it is irrelevant to the slot opening, the oil discharge amount is changed by the slot opening opening interlocking mechanism that is easily changed after factory shipment. It does not change. Therefore, since a predetermined amount of oil can be supplied to the engine, the engine can be operated normally. Conventionally,
It is possible to reduce the discharge amount that had been increased in anticipation of fluctuations after shipment from the factory.

Next, the device of the present invention will be described in detail.

FIG. 3 shows a plan sectional view of the embodiment, and 10 is an input shaft, which is connected to, for example, a crankshaft 9 (see FIG. 1) and is rotated by the rotation of the engine. This input shaft 10 is
As shown in the figure, the drive shaft 11 and the joint portion 11
and a driven shaft 12 connected by b. The drive shaft 11 is provided with a screw gear 11a, and the screw gear 11a is a third gear.
The plunger 13 is rotated by engaging with a large gear 14 provided on the illustrated plunger 13. Driven shaft 12 in FIG.
4 holes 12a are formed obliquely from above in the hole 1.
A centrifugal weight 15 made of a steel ball is movably inserted in 2a. Reference numeral 16 denotes an annular body, which is provided so as to cover the centrifugal weight 15 from above, and the movable body 17 is configured with the centrifugal weight 15. The moving body 17 moves upward due to the centrifugal force of the centrifugal weight 15 that accompanies the rotation of the driven shaft 12. Reference numeral 29 denotes an engine speed detector, which is used for the moving body 17 and the input shaft 1.
It is composed of 0 and.

Reference numeral 18 denotes a pin body, which is hollow and has a spring 30 provided between it and the pump case 19 to press the annular body 16 downward, as shown in FIG. On the other hand, the pin body 18 is pressed upward by the movement of the movement 17, that is, by the annular body 16. A tapered sloped portion 18a is formed on the outer periphery of the pin body 18, and the sloped portion 18a is in sliding contact with the cam 40 projecting from the end face of the plunger 13 in the axial direction. The cam 40 includes a convex portion 20 and a central convex portion 21. As shown in FIG. 3, the convex portion 20 has a circumferential (cylindrical) shape, and smooth unevenness in the circumferential direction is formed point-symmetrically around the central convex portion 21. A portion 20a and a high place, that is, a high convex portion 20b are provided,
The central convex portion 21 is lower than the high convex portion 20b.

With the cam 40 and the pin body 18, the discharge amount adjuster 2
2 is configured.

In FIG. 5, 23 is a plunger pump, which forms a pump chamber 24 between the pump case 19 and the plunger 13. The plunger 13 is rotated in the pump case 19 by the large gear 14, and the two convex portions 20 and 21 are brought into sliding contact with the side surfaces of the pin body 18 in association with this rotation. Slide in the axial direction. The plunger 13 has an inlet / outlet passage 13a which communicates with the pump chamber 24 and through which oil flows, an inlet 13b for sucking oil into the inlet / outlet passage 13a, and an outlet 13c through which oil is discharged from the inlet / outlet passage 13a. And have been drilled.

The pump case 19 is a machine room 2 in which the pin body 18 is housed.
5 is integrally formed, a lid 26 is attached to the side portion thereof, and a lower case 27 accommodating the moving body 17 is attached to the lower portion thereof. The pump case 19 has a suction hole 19
The holes a and 19b are provided at opposite positions, and the suction hole 19a and the suction hole 19b communicate with each other through the machine chamber 25. The inlet 13b of the plunger 13 is
Each time it rotates 0 °, it communicates with one of the suction holes 19a and 19b alternately. During this communication, the low convex portion 20a of the circumferential convex portion 20 and the large diameter portion 18b of the pin body 18, or the central convex portion 21 and the slope portion 18a of the pin body 18 or the large diameter portion 18b of FIG. Slidably contact with each other, the plunger 13 is pushed by the spring 28, and the pump chamber 24 becomes large. The suction hole 19b faces the lower case 27, and oil is introduced into the lower case 27 to lubricate the lower case 27. Both suction holes 19a and 19b communicate with the suction passage 7 shown in FIG.

On the other hand, the discharge passage 8 is communicated with discharge holes 19c, 19c formed in the pump case 19 shown in FIG. The discharge holes 19c, 19c are formed at positions facing each other in a direction different from the suction hole 19a by 90 ° in the circumferential direction of the plunger 13, and are alternately arranged at the discharge ports 13c of the plunger 13 on the suction side. Communicate. During this communication, the high convex portion 20b of the circumferential convex portion 20 and the large diameter portion 1 of the pin body 18
8b is brought into sliding contact, and the pump chamber 24 becomes smaller. That is,
The oil discharge amount of the plunger pump 23 (hereinafter referred to as the oil discharge amount Vp) is set by the rotation speed of the plunger pump 23 (hereinafter referred to as the rotation speed Np) and the stroke in the axial direction.

In addition, in order to prevent the pin body 18 from moving in the vertical direction by the pressing force of the central convex portion 21 by the spring 28 of FIG.
The shape change of 8a is set to be sufficiently small, and the spring 28
It is needless to say that the reaction force of the spring 30 and the structure of the moving body 17 are set so that the pin body 18 can move with respect to the frictional force generated by.

Next, the operation of the above configuration will be described.

As the crankshaft 9 shown in FIG. 1 rotates, the input shaft 10 shown in FIG. 4, that is, the drive shaft 11 and the driven shaft 12 rotate. The centrifugal weight 15 tries to move upward from the position indicated by the alternate long and short dash line by the centrifugal force generated by this rotation. On the other hand, the pin body 18 in FIG. 6 is pressed downward by the spring 30.

When the rotational speed N ₁ or less in the low speed range of FIG. 2 is lower than the operation start speed N ₁ , the reaction force of the spring 30 is set to be larger in the state of FIG. 6 than the rising force of the centrifugal weight 15 of FIG. 4 due to the centrifugal force. And the pin body 18 is at the lower position. That is, the discharge amount adjuster 22 shown in FIG. 3 has not been operated yet. On the other hand, the large gear 14 meshes with the screw gear 11a, and the plunger 13
Rotates. By this rotation, the central convex portion 21 and the high convex portion 20b of the circumferential convex portion 20 are brought into sliding contact with the large diameter portion 18b of the pin body 18 of FIG. Further, by the above rotation, the suction port 13b and the discharge port 13c of the plunger 13 are alternately communicated with the suction holes 19a and 19b and the discharge hole 19c of the pump case 19, respectively. Thus, the plunger pump 23 has a constant small stroke and a slow rotation speed Np.
The oil discharge amount Vp linearly increases in proportion to the rotation speed N, as shown in FIG. 2, to correspond to the ideal oil supply amount V ₁ .

When the rotation speed N is from the operation start rotation speed N ₁ to the operation stop rotation speed N ₂ or less in the high speed range, the centrifugal weight 1 shown in FIG.
The ascending force of 5 is larger than the reaction force of the spring 30 in the state of FIG. 6, and the pin body 18 moves upward. That is, the rotation speed detector 29 detects the operating rotation speed N ₁ (see FIG. 2) and moves the pin body 18 in the arrow A direction. As a result, the central convex portion 21 is brought into sliding contact with the slope portion 18a, and the stroke of the plunger 13 is increased. The rate of increase of this stroke with respect to the rotation speed N is the centrifugal force of the centrifugal weight 15 in FIG. 4, that is, the square of the rotation speed N, and the slope portion 18 in FIG.
It is determined by the shape of a. The discharge amount adjuster 22 including the both convex portions 20 and 21 and the pin body 18 changes the stroke of the plunger pump 23 to change the oil discharge amount Vp shown in FIG. 2 to the ideal oil supply amount V _{1 as described above.}
It corresponds to.

When the rotation speed N reaches the operation stop rotation speed N ₂ , the pin body 18 comes into contact with the inside of the pump case 19 as shown in FIG. 5, and the pin body 18 no longer rises. At the above operation stop rotation speed N ₂ (see FIG. 2), the stroke of the plunger 13 becomes maximum and constant. That is, the rotation speed detector 29 shown in FIG. 4 detects the operation stop rotation speed N ₂ (see FIG. 2) so that the discharge amount adjuster 22 shown in FIG. 5 makes the stroke of the plunger pump 23 constant. keep. As a result, the oil discharge amount Vp in FIG. 2 linearly increases in proportion to the rotation speed N, and corresponds to the ideal oil supply amount V ₁ .

In the above configuration, the oil discharge amount Vp changes in proportion to the product of the stroke of the plunger pump 23 in FIG. 5 and the rotation speed Np, that is, two parameters based on the rotation speed N in FIG. Therefore, it is easy to correspond to the ideal oil supply amount V ₁ that changes intricately with respect to the rotation speed N.

By the way, the rotation speed detector 29 of FIG. 4 has unstable operation characteristics at low rotation speed, and may not be able to accurately detect the engine rotation speed N. Therefore, the discharge amount adjuster 2
There is a possibility that the stroke adjustment of the plunger 13 shown in FIG. In contrast, the second
Below the operating speed N _{1 in the} figure, the rotational speed detector 29 (fourth
The stroke of the plunger 13 (see FIG. 3) is constant regardless of the stroke. Therefore, the oil discharge amount Vp changes linearly in proportion to the engine speed N, so that the set oil discharge amount Vp can be obtained even in the low speed range. Therefore, a mechanical rotation number detector 29 (see FIG. 4) having a simple structure can be adopted.

Further, even if an attempt is made to maintain the engine speed N at a constant value, it will always fluctuate slightly, so the centrifugal weight 1 shown in FIG.
It is conceivable that 5 vibrates. On the other hand, since oil is introduced into the lower case 27 through the suction hole 19b in FIG. 5, this oil is collected in the centrifugal weight 15 in FIG.
It becomes a resistance of the vertical movement of and can prevent its vibration. Also,
Therefore, the operation of the rotation speed detector 29 is stabilized, and the operation start rotation speed N ₁ in FIG. 2 can be reduced.

Further, the ideal amount of lubrication V ₁ is linearly proportional to the rotation speed N in the high speed range. On the other hand, as in the low speed range, the oil discharge amount Vp is linearly changed in proportion to the rotation speed N, so that the oil discharge amount Vp can be made to correspond to the ideal oil supply amount V ₁ .

By the way, in the vicinity of the operation start rotational speed N ₁ , the oil discharge amount Vp is smaller than the ideal oil supply amount V ₁ , but it is considered that the oil is insufficient. However, the ideal amount of lubrication V ₁ is the value during steady operation with the throttle fully open, and on the other hand, in the low speed range around the operation start rotation speed N ₁ or less, the throttle is hardly fully opened and operated at a constant speed for a long time. Therefore, even if the ideal oil amount is V ₁ or less, there is no fear that the oil amount will be insufficient, and on the contrary, there is an advantage that waste of oil is prevented.

Further, since the stroke of the plunger 13 is changed by moving the pin body 18 in the axial direction of FIG. 5, unlike the case of moving the pin body 18 in the circumferential direction, the pin body 18 and The structure of the rotation speed detector 29 shown in FIG. 4 is simplified.

By the way, in the case of the engine having the characteristic that a large amount of accumulated oil is accumulated in the crank chamber 2 in FIG. 1, a large amount of accumulated oil is accumulated during a rapid deceleration, while a large amount of accumulated oil is introduced into the combustion chamber during a rapid acceleration. Therefore, it is considered that the oil discharge amount Vp shown in FIG. 2 becomes insufficient at the time of sudden deceleration and becomes excessive at the time of sudden acceleration.

Here, when the pin body 18 of FIG. 6 is moved, a frictional force is generated by the springs 28 and 30. By this frictional force, the movement of the pin body 18 in the directions of the arrows A and B is deviated from the timing when the moving body 17 is about to move. This deviation increases when the moving body 17 moves suddenly, that is, when the vehicle 17 suddenly accelerates or decelerates. Therefore, at the time of sudden acceleration, for example, the rotational speed N increases from the point O _{1 in} the low speed range in FIG. 2, whereas the movement of the pin body 18 in the direction of arrow A in FIG. Since there is a delay, that is, the increase in the plunger stroke is slightly delayed, the oil discharge amount is linearly changed to a point O as shown in FIG.
After rising to _2, it changes like the oil discharge amount Vp (UP). On the other hand, during rapid deceleration, for example, the rotational speed N decreases from the point O _{3 in the} high speed range, whereas the decrease in the plunger stroke is slightly delayed as opposed to during acceleration, so the oil discharge amount linearly reaches the point O _4. After the descent, it changes like the oil discharge amount Vp (down). As a result, a large amount of oil is discharged at the time of sudden deceleration, and a small amount of oil is discharged at the time of sudden acceleration, so that the excess or deficiency of the oil of the engine having the above characteristics can be compensated. That is, for example, by setting the above-mentioned frictional force, a change in the oil discharge amount Vp sets a response delay with respect to a change in the rotation speed N, and exhibits a hysteresis characteristic,
The excess and deficiency of the above oil can be supplemented.

The control method of the oil discharge quantity Vp having an oil discharge amount Vp and Hisuterishiru characteristics of devices of the present invention, since it is made to correspond to the ideal amount of oil V _1, although not perfectly match the ideal lubrication amount V ₁ Needless to say, it is included in the embodiments of the method of the present invention. Further, in the method and apparatus of the present invention, it goes without saying that the oil discharge amount Vp in the low speed range may be larger than the ideal oil supply amount V ₁ .

〔The invention's effect〕

As described above, according to the present invention, the oil pump is controlled only by the reciprocating stroke of the plunger and the rotation speed of the engine, and the discharge amount regulator and the rotation speed detector of the oil pump are the pin bodies. And the movable body are brought into contact with each other, and the pin body and the movable body are provided with a predetermined response delay, the oil is supplied to the engine at an oil supply amount close to an ideal amount, white smoke is generated, and combustion chamber is generated. It is possible to effectively prevent the adhesion of carbon on the wall and improve the reliability of lubrication.

Furthermore, according to the present invention, the stroke of the plunger is changed by the discharge amount adjuster that operates in conjunction with the engine speed detector provided inside the oil pump, so that the slot and the lever of the oil pump are changed. Cables and the like to be connected, an ignition pulse detection device of the engine, a pulse signal transmission device, a wire for connecting the servo motor and the lever of the oil pump, etc. can be eliminated, and productivity is improved and cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a two-cycle engine to which the present invention is applied, FIG. 2 is a characteristic diagram showing the relationship between engine speed and oil amount by the method of the present invention, and FIG. An example of a plan sectional view, FIG. 4 is a sectional view taken along the line IV-IV of FIG. 3, FIG. 5 is a sectional view taken along the line VV of FIG. FIG. 6 is a sectional view taken along line VI-VI of FIG. 3. 6 ... Oil pump, 10 ... Input shaft, 13 ... Plunger, 17 ... Moving body, 18 ... Pin body, 18a ... Slope portion, 22 ... Discharge rate adjuster, 23 ... Plunger pump, 29 ...... Rotation speed detector, 40 ...... Cam, V ₁ ...... Ideal oil supply amount during steady operation when the throttle valve is fully open, Vp ...... Oil discharge amount.

Claims (1)

[Claims] 1. An ideal oil supply amount during steady operation when the throttle valve is fully opened is set corresponding to the engine speed, and the oil discharge from the oil pump is based on the change in the engine speed. A separate refueling device for a two-cycle engine, in which the amount is changed in accordance with the ideal amount of oil supply, and a predetermined response delay is set for the change in the amount of oil discharge with respect to the engine speed. And a rotation speed detector of the engine provided in the engine and the plunger reciprocates in the axial direction while rotating by the driving of the engine, and the oil discharge amount is set by the stroke of the reciprocation and the rotation speed of the plunger. The plunger pump works in conjunction with the rotation speed detector and the stroke of the plunger pump is changed to control the oil discharge amount. A discharge amount adjuster for adjusting an ideal oil supply amount during steady operation when the tuttle valve is fully opened.The discharge amount adjuster is provided with a cam formed on an end face in the axial direction of the plunger and slidably contacting the cam. The rotation speed detector comprises an input shaft driven by the rotation of the engine and a centrifugal force generated by the rotation of the input shaft. And a moving body that moves the pin body in the axial direction by means of a moving body.