JP3134006B2 - Lubricating device for two-cycle engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating device for supplying lubricating oil to a two-stroke engine through an intake passage.

[0002]

2. Description of the Related Art Conventionally, as a lubricating device for a two-cycle engine, a plunger driven in conjunction with the rotation of the engine is used.
The oil pump reciprocates and supplies oil to the engine at a flow rate proportional to the engine rotation speed from the oil tank to the engine via a three-way solenoid valve.The computer controls the supply amount according to the operating conditions of the engine. it shall be performed by the duty control of the opening and closing of the solenoid valve was present.

[0003]

However, the above-mentioned data
Duty control uses a pulse wave to control the solenoid of a three-way solenoid valve.
Switch the supply passage by turning the
Lubricating oil supply is controlled by changing the duty ratio.
U. The duty ratio determines the oil supply time as the pulse wave period.
One cycle is the supply time and the non-supply time
The sum of Low engine speed and throttle
When the opening is small, reduce the duty ratio to
Supply the lubricating oil to the engine. At this time,
Reciprocating plunger reciprocating in conjunction with the rotation speed of the gin
The frequency is reduced, but the pump
Supply oil to the engine if no oil is discharged
Supply time cannot be adjusted during that time.
A certain time must be secured so that there is reciprocation of the lang
Must. Therefore, in order to reduce the duty ratio,
Lengthens the pulse wave period in duty control
But the longer the cycle, the longer the non-supply time,
There was a risk of the engine burning.

The present invention has been made in order to solve the above-mentioned drawbacks of the prior art, and an object of the present invention is to turn on / off the energization of a solenoid of a three-way solenoid valve.
By turning off, the direction of the supply passage from the oil pump is controlled, and the duty ratio is used to control the discharge amount. By adjusting the plunger stroke by interlocking with a servomotor that drives the exhaust movable valve so that the exhaust timing is controlled based on at least the engine rotation speed
Even if the amount of lubricating oil supplied to the engine is reduced,
An object of the present invention is to provide a lubricating device for a two-stroke engine characterized by preventing problems such as seizure .

[0005]

In order to achieve the above object, a lubricating apparatus for a two-stroke engine according to the present invention comprises an engine
With a movable exhaust valve that opens in response to an increase in the rotational speed of the
A lubricating oil supply device for a cycle engine, comprising a plunge
Engine driven oil pump with reciprocating oil pump and pump
To supply the lubricating oil supply passage from the engine to the engine
To either the passage or the return passage communicating with the oil tank.
Three-way solenoid valve that switches to pass through and switching of this valve
System that controls duty based on engine operating conditions.
Oil supply device for a two-stroke engine equipped with a control device
In the above, the stroke of the plunger is
When controlling the discharge amount of the oil pump in conjunction with the driving means
In both cases, the three-way solenoid valve duty
By controlling the oil ratio, lubricating oil
Supply the oil pump discharge amount and the three-way solenoid valve duty.
Low supply of lubricating oil
The duty control cycle of the three-way solenoid valve
Duty when the supply amount is determined only by the one-way solenoid valve
Control the three-way solenoid valve so that it is shorter than the control cycle
It is characterized by the following.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the figure, reference numeral 1 denotes a lubricating device for a two-stroke engine according to the present invention, the device comprising an oil tank 4 and an engine 2.
Are connected to the oil pump 3 via the three-way solenoid valve 7 via the supply passages 5, 6, and 8, and the solenoid 11 of the three-way solenoid valve 7 is operated to connect the supply passage 6 and the return passage 9 with each other. It is configured to be connected to Three-way solenoid valve 7
Are provided with an inlet 7A communicating with the supply passage 6, an outlet 7B communicating with the supply passage 8 to the engine 2, and an outlet 7C communicating with the return passage 9;
2 is urged by an urging spring, and has an inflow port 7A and an outflow port 7A.
B is in a position to communicate with the opening. And the solenoid 11
Is excited, the valve rod 12 cuts off the communication between the inflow port 7A and the outflow port 7B, moves to the position communicating with the inflow port 7A and the outflow port 7C, and communicates with the return passage 9 to form a return circuit. It is configured to be.

On the other hand, the oil pump 3 has a casing 13, in which a cylindrical hole 14 extending in the left-right direction is formed, and a rotary shaft 15 which rotates around its axis is formed in the hole 14. And the rotating shaft 15 is connected to the pump drive shaft 16 of the engine 2 by the worm gear 32.
Is rotated through. The rotation shaft 15 rotates in proportion to the rotation speed of the engine 2. A plunger hole 17 is formed in the rotary shaft 15, and a left end of the plunger hole 17 is closed by a plug 18, and a plunger 19 is fitted on the right end side so as to be slidable in the axial direction. A pump chamber 20 is provided between the plug 18 and the left end of the plunger 19. Then, in the pump chamber 20, the plunger 19 is interlocked with the rotation of the rotary shaft 15 so that the spring 33 and the cam member 34 (3
4 _1, 34 _2, 34 ₃ reciprocates by the action of) is adapted to the pumping action for discharging the lubricating oil.

[0008] The casing 13 is provided with an oil supply hole 21 for communicating the outside of the casing 13 toward the inside of the hole 14.
Is connected to the supply passage 5. Also, the rotating shaft 1
5 has an oil hole 22 for connecting the pump chamber 20 to the outside of the rotary shaft 15, and the oil hole 22 is connected to an oil discharge hole 23. Further, a one-way valve 24 is provided in the oil discharge hole 23, and the outlet side thereof is connected to the engine 2 via the three-way solenoid valve 7. Then, with the rotation of the pump drive shaft 16, the rotation shaft 1 is rotated via the worm gear 32.
If the 5 is rotating, when the oil hole 22 matches the oil supply hole 21, the plunger 19 is enlarged pumping chamber 20 moves rightward by the action of the cam member 34 (34 _1, 34 ₂₎ Then, the lubricating oil in the oil tank 4 is sucked into the pump chamber 20 through the oil supply hole 21 and the oil hole 22,
Similarly, when the oil hole 22 coincides with the oil discharge hole 23 when the rotary shaft 15 is rotating, the plunger 19 is moved by the spring 33 due to a different operation of the same cam member 34 (34 ₁ , 34 ₃ ). Pushed to the left, the pump chamber 20 is contracted, and the lubricating oil in the pump chamber 20 is discharged through the oil hole 22, the oil discharge hole 23 and the one-way valve 24 and supplied to the engine 2. . As described above, the oil hole 22 sequentially and intermittently coincides with the oil supply hole 21 and the oil discharge hole 23 with the rotation of the rotary shaft 15, while the plunger 19 repeats reciprocating movement to the left and right, thereby lubricating the engine. Oil is supplied.

However, the supply amount can be increased or decreased according to the opening angle of the exhaust movable valve at the exhaust port.
Is provided with an adjusting device 25, the configuration of which is as follows. That is, the disk 26 is located at the right end of the plunger 19.
Is screwed, and a pulley 27 is rotatably fitted to the right end of the casing 13 opposed thereto.
Is biased rightward by a spring 28. Also this pulley 2
A cam groove 29 is formed spirally in the circumferential direction at the boss portion 7, and a stopper 30 that engages with the cam groove 29 is screwed to the casing 13. When the pulley 27 is rotated about the axis, the cam groove 2 which rotates
9 engages with the stopper 30 to move the pulley 27 in the left and right axial directions.

The right end surface of the pulley 27 has a stopper surface 31.
And the stopper surface 31 faces the disk 26. When the pulley 27 moves rightward by rotation, it comes into contact with the disk 26 halfway, so that the stroke of the reciprocating movement of the plunger 19 is shortened, and the discharge amount of the oil pump is limited. Also, when the opening of the exhaust movable valve is increased, the pulley 27 rotates,
The cam engagement of the cam groove 29 with the stopper 30 causes the pulley 2
7 moves to the left, the disk 26 separates from the stopper surface 31, and the stroke of the plunger 19 increases, so that the discharge amount of the oil pump increases. The pulley 27 is a servomotor 2 for adjusting the opening and closing of an exhaust movable valve disposed at an exhaust port.
B is interlocked with the pulley 2C. Figure 3 shows engine rotation
A control characteristic diagram showing the relationship between the speed and the opening of the exhaust movable valve.
However, in the low engine speed range, the servo motor
Data is along the line below the lower dotted line in the figure
Is controlled by the pulley of the servo motor.
The discharge amount of the oil pump 3 is controlled with play
I am trying not to be.

Here, the control method of the present invention will be described with reference to FIG. 2 in comparison with the prior art. 2 (a) and 2 (b) are schematic diagrams of a conventional two-stroke engine and a lubricating device for a two-stroke engine according to the present invention, and FIGS. 2 (c) and 2 (d) show typical duty ratio control diagrams in the duty control. Oh those were
The width of the rising pulse wave is
The duty ratio depends on the pulse supply period.
The interval between pulse waves is not available.
It is pay time. In the conventional lubricating device for a two-stroke engine, as can be seen from FIGS. 2A and 2C, the discharge amount of the oil pump is supplied in proportion to the rotational speed of the engine. In the high speed range where the opening is input and duty control is performed, the required amount of lubricating oil is supplied to the engine, and the low speed range and small throttle opening
In the area, no supply time to close the outlet 7B of the three-way solenoid valve
Inside the excess lubricating oil returns to the oil tank and passes through the passage
It is refluxed. When the duty ratio is 10%,
Since a predetermined time is secured as described above, a pulse wave
Cycle becomes longer, and if the supply rate is further reduced,
Supply time will be extended.

On the other hand, in the present invention, on the other hand, FIG.
(B) As shown in (d), the discharge amount of the oil pump itself is
Linked to a servo motor that moves the exhaust movable valve as shown in Fig. 3.
So that the oil pump discharges per unit time.
The output decreases as the rotation speed decreases. Therefore,
As shown in (d), the discharge rate of the pump is reduced to 20%,
The cycle of the lus wave is shortened and the duty ratio of the three-way solenoid valve is set to 5
If it is set to 0%, the duty ratio of (c) eventually becomes 10%.
A corresponding supply can be obtained. Duty ratio 50%
In this case, the non-supply time is shortened,
There is a margin in safety, and the duty ratio is less than 50%
As a result, the supply amount can be further reduced.

Next, the operation and effect of the embodiment of the present invention will be described. First, in the lubricating device for a two-stroke engine of the present invention, the oil pump 3 linked to the rotation of the engine 2 is driven by the oil pump of the engine 2. While the shaft 16 is driven to rotate the rotating shaft 15, the urging spring 33 and the cam members 34 (34 ₁ , 34 ₂ , 34) are interlocked with the rotation.
3), the plunger 19 reciprocates, and the oil hole 22 intermittently coincides with the oil supply hole 21 and the oil discharge hole 23 so that lubricating oil is supplied to the engine 2. That is, when the oil hole 22 coincides with the oil supply hole 21 when the rotation shaft 15 is rotated via the worm gear 32 with the rotation of the pump drive shaft 16, the oil supply hole 21 is When the lubricating oil in the oil tank 4 is sucked through the oil hole 22 and the oil hole 22 matches the oil discharge hole 23, the lubricating oil is discharged through the oil hole 22, the oil discharge hole 23 and the one-way valve 24 and supplied to the engine 2. .

On the other hand, when the discharge amount of the oil pump 3 is adjusted, the opening degree of the exhaust movable valve 2A that is appropriate for the rotation speed of the engine 2 is input and calculated by the computer 10, and the output signal of the calculated value is output. Pulley 2 of the adjusting device 25 in conjunction with the pulley 2C of the servomotor 2B driven by the
7 rotates together with the casing 13, and when the engine rotational speed is low, the rightmost stopper surface 31 abuts against the disk 26, and the stroke of the plunger 19 is short, so that the discharge amount is small. 27
Is rotated and the casing 13 moves to the left, the stroke of the plunger 19 becomes longer, and the discharge amount of the oil pump 3 increases. On the other hand, the rotational speed of the engine 2 and the throttle opening are input to the computer 10 and calculated, and the outlet 7B of the three-way solenoid valve 7 is closed and the outlet 7C is opened intermittently based on the calculated values. , Duty control is performed.

[0016]

As described above in detail, the lubricating device for a two-stroke engine according to the present invention can be used to increase the rotational speed of the engine.
Of two-stroke engine with movable exhaust valve
An oil supply device, in which the plunger reciprocates.
-Driven oil pump and lubricating oil supply from pump
Supply passage or oil tank that connects the passage to the engine
Switch to communicate with one of the return passages communicating with
Three-way solenoid valve and the switching of this valve
And a control device for performing duty control according to the situation.
In the lubricating oil supply device for a vehicle engine, the plan
The stroke of the jaw is linked to the drive
Control the oil pump discharge and oil pump discharge.
Controlling the duty ratio of the three-way solenoid valve according to the output
Oil pump to supply lubricating oil to the engine
And the duty ratio of the three-way solenoid valve
So that the three-way electromagnetic
The valve duty control cycle is controlled by the three-way solenoid valve only
Shorter than the duty control cycle when
Is configured to control the three-way solenoid valve
Therefore, the duty control cycle can be shortened in the low oil supply area.
No supply time in one cycle of duty control
Engine becomes shorter, and even if the lubricating oil supply
Problems such as seizure can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a two-stroke engine lubrication apparatus according to an embodiment of the present invention.

FIG. 2A is a schematic view of a conventional example. (b) is a schematic diagram of an example according to the present invention. (c) is a diagram showing a control mode of the conventional example. (d) is a diagram showing a control mode of the embodiment of the present invention.

FIG. 3 is a control characteristic diagram of a servomotor used in the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Lubricating device for two-stroke engine of the present invention 2 Engine 2A Exhaust movable valve 2B Servo motor 2C Pulley 3 Oil pump 4 Oil tank 5 Supply passage 6 Supply passage 7 Three-way solenoid valve 7A Inlet 7B Outlet 7C Outlet 8 Supply passage 9 Return passage 10 Computer (CPU) 11 Solenoid 12 Valve rod 13 Casing 14 Hole 15 Rotary shaft 16 Pump drive shaft 17 Plunger hole 18 Plug 19 Plunger 20 Pump chamber 21 Oil supply hole 22 Oil hole 23 Oil discharge hole 24 One-way valve 25 Adjustment 26 disk 27 pulley 28 spring 29 cam groove 30 stop 31 stop face 32 the worm gear 33 spring 34 (34 _1, 34 _2, 34 ₃₎ the cam member

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F01M 1/16 F01M 3/00 F01M 1/02 F02B 25/20

Claims (1)

(57) [Claims] An exhaust system that opens in response to an increase in engine speed.
Oil supply device for two-stroke engine having pneumatic movable valve
An engine-driven oil pump in which the plunger reciprocates
And the lubricating oil supply passage from the pump to the engine
Supply passage or return passage communicating with the oil tank
A three-way electromagnetic valve for switching to crab communicates, Dew switching of the valve according to the operating condition of the engine
Of a two-stroke engine with a control device
In the lubricating oil supply device, the stroke of the plunger is used as driving means for the exhaust movable valve.
In conjunction with controlling the oil pump discharge, oil
The duty ratio of the three-way solenoid valve is controlled according to the pump discharge amount.
Control the amount of lubricating oil supplied to the engine.
Depending on the discharge rate of the oil pump and the duty ratio of the three-way solenoid valve.
In the low lubrication oil supply range, the duty of the three-way solenoid valve
When the supply cycle is determined only by the three-way solenoid valve
So that the cycle of duty control in
Two-cycle engine characterized by controlling a one-way solenoid valve
Lubricating oil supply device.