JPH0732889Y2 - Refueling flow controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is an oil supply flow rate control device for performing separate lubrication of a two-cycle engine, which is mechanically connected to the engine and driven in association with the rotation of the engine. By using a mechanical oil pump and a three-way solenoid valve whose discharge amount changes only depending on the rotational speed of the engine, by returning excess oil discharged by the mechanical oil pump to the oil tank, the operating condition was adapted. The present invention relates to a refueling flow rate control device for refueling.

[Prior Art] An oil pump that controls an oil discharge amount by a discharge amount control cam shaft that rotates in association with a throttle valve opening of a carburetor is
It has been widely used for separate lubrication of two-cycle engines, but it is not always necessary to adequately supply the amount of oil required by the engine simply by controlling the amount of oil discharge related to the opening degree of the throttle valve of the carburetor. However, the amount of oil required by the engine changes depending on the operating region and operating conditions of the engine. Therefore, the amount of oil discharge is set so that the oil supply flow rate will not become insufficient in any operating range and operating condition, so that more oil than necessary may be supplied, which is uneconomical and also causes oil combustion. It is also not preferable from the viewpoints of pollution of the inside of the engine due to air pollution and air pollution. Since the applicant can select the relationship between the throttle valve opening and the oil discharge amount to some extent according to the operating region and the operating state, the applicant of the present application has applied the Japanese Patent Application No. 62-163198 to form the discharge amount control camshaft. An oil pump has been proposed in which two different cam surfaces are formed and the discharge amount control cam is moved in the axial direction to select the relationship between the throttle valve opening of the carburetor and the oil discharge amount. In FIG. 5, reference numeral 1 is a pump casing, 2 is a cylinder, 3 is a plunger, a worm wheel 4 is formed, and a lead cam 5 is arranged at one end,
Since the discharge amount control cam shaft 6 is arranged opposite to the lead cam 5, when the tribing worm 7 meshing with the worm wheel 4 is driven by the engine to rotate, the plunger 3 rotates at the same time,
When the lead cam 5 and the lead cam guide surface 6-1 of the discharge amount control cam shaft 6 are brought into contact with each other, a reciprocating motion is performed to perform a pump action, and the cam face 6-2 or the cam face of the discharge amount control cam shaft 6 is performed. The projection 8 at the center of the plunger end face abuts against any of 6-3, the reciprocating stroke of the plunger 3 is limited, and the rotation of the discharge amount control cam shaft 6 controls the discharge amount of oil. The movement selects the cam surface 6-2 and the cam surface 6-3. When the electrical contact 9 is closed depending on the operating region and operating condition of the engine, the solenoid valve guides the intake negative pressure of the engine to the actuator 10 for negative pressure operation to pull the discharge amount control cam shaft 6 downward in the figure. The discharge amount is controlled by the cam surface 6-2 and the solenoid valve guides the atmosphere to the actuator 10 when the electric contact 9 is opened. Therefore, the discharge amount control cam shaft moves upward in the figure to move the cam surface 6-3. The discharge amount is controlled by.

The applicant has also formed an annular groove in the plunger according to Japanese Patent Application No. 62-174478, and moves the inside and outside of the annular groove by an actuator (diaphragm device) that responds to the engine generated pressure that changes with changes in the operating condition of the engine. A moving pin member is arranged in the pump casing, and when the differential pressure between the pressure generated by the engine and the atmospheric pressure is higher than a specific value, the pin member retreats out of the annular groove to reciprocate the plunger. The stroke is controlled by the discharge amount control cam shaft, and when the pressure difference between the pressure generated by the engine and the atmospheric pressure is lower than a specific value, the pin member enters the annular groove and reciprocates the plunger. An oil pump has been proposed in which the stroke is limited to a value smaller than the maximum value of the reciprocating stroke controlled by the discharge control camshaft.

Thus, in the oil pump proposed in Japanese Utility Model Application No. 62-163198, it is only possible to switch the relationship between the throttle valve opening and the oil discharge amount in two stages depending on the operating state. In the oil pump proposed by No. 174478, even if the throttle valve is above a specific opening, even if the opening becomes large, it is only suppressed so that the oil discharge amount does not increase, and the throttle valve that is frequently used is low open. There is no relation to the discharge amount of oil in the temperature range, and the problem of excessive oil supply to the engine has not been sufficiently solved.

On the other hand, in Japanese Utility Model Publication No. 62-33929, a computer inputs a signal for calculating and outputting a rotational speed signal of an engine and a throttle valve opening signal to an exciting winding 11 of an electromagnetic pump shown in FIG. An oil pump for a two-cycle engine is disclosed in which the plunger 12 is reciprocated and the oil supply flow rate is controlled by the duty ratio of the output signal of the computer.
Thus, the electromagnetic hoop having the above structure has an advantage that the fuel is supplied in conformity with the operating condition of the engine, while the suction side check valve 1
3, and the discharge-side check valve 14 opens and closes due to the change in the hydraulic pressure in the homp action chamber 15 accompanying the reciprocating motion of the plunger 12, so the force of the spring 16 that biases the valve in the closing direction is small,
Even if foreign matter such as dust enters between the valve and the valve seat,
The valve function and thus the pump action is impaired and the excitation winding
The disconnection of 11 and other electrical failures may cause pumping failure and engine seizure.

[Problems to be solved by the invention] It is possible to continuously control the flow rate of oil supply suitable for the operating condition of the engine, and even if fine foreign matter enters and electrical failure occurs, oil supply may be stopped. It is an object of the present invention to obtain a refueling flow rate control device which does not exist.

[Means for Solving the Problem] A mechanical system that is mechanically connected to an engine at an inlet of a three-way solenoid valve and is driven in association with rotation of the engine to discharge oil at a flow rate proportional to the rotational speed of the engine. A discharge port of an oil pump; an oil supply passage to the engine at a normally open outlet of the three-way solenoid valve; an oil tank at which a suction port of the mechanical oil pump is connected to a normally closed outlet of the three-way solenoid valve Is connected to the oil return passage to the computer, and a signal output from the computer by inputting and operating the operating parameter signal of the engine is input to the excitation winding of the three-way solenoid valve, and the opening of the normally closed outlet is duty-cycled. Controlled, excess oil discharged by the mechanical oil pump is returned to the oil tank through the return passage,
The engine is configured to be able to supply oil with a flow rate suitable for the operating condition.

[Operation] When the excitation winding is not energized, all the oil discharged from the mechanical oil pump is supplied to the engine through the normally open outlet of the three-way solenoid valve, and when the excitation winding is energized, When the open outlet is closed and the normally closed outlet is opened (hereinafter, the normally closed outlet is simply called open), the oil discharged from the mechanical oil pump passes through the normally closed outlet and the return passage. Returned to the oil tank. Therefore, the computer inputs an engine operation parameter, for example, a throttle valve opening signal of the carburetor and a valve signal of the normally closed outlet, which outputs by calculating the temperature signal of the engine, to the excitation winding of the three-way solenoid valve, By controlling the valve opening duty of the closed outlet, it is possible to perform the oil supply flow rate control suitable for the operating state of the engine.

Since the spring that presses the valve body against the valve seat on the normally closed outlet side is stronger than the spring 16 of the electromagnetic valve that presses the valve body of the check valve against the valve seat, the valve function may be impaired by a small amount of foreign matter. Even if the normally closed outlet does not open due to an electrical failure, only the entire amount of oil discharged from the mechanical oil pump is supplied to the engine, and seizure may occur in the engine. In addition, there is no oil supply, and the oil can be supplied steplessly by the duty control, which is suitable for the engine operating state.

[Embodiment] FIG. 1 shows an oil supply flow rate control device of the present invention, in which reference numeral 20 is mechanically connected to an engine by a mechanical oil pump,
It is driven in conjunction with the rotation of the engine, and discharges oil at a flow rate proportional to the rotation speed of the engine. Reference numeral 21 is a three-way solenoid valve, and 22 is an oil inlet of the three-way solenoid valve 21, which is connected to the discharge port of the mechanical oil pump 20. Reference numeral 23 is a normally open outlet of the three-way solenoid valve 21, to which an oil supply passage to the engine (not shown) is connected. 24 is the three-way solenoid valve 21
Is connected to an oil tank 26 via an oil return passage 25. The suction port of the mechanical oil pump 20 is connected to the oil tank 26. Reference numeral 27 denotes a valve element, which is pressed against the valve seat on the normally closed outlet 24 side by the first spring 28. 29 is an excitation winding, which is connected to the output side of the computer 30. Reference numeral 31 denotes a piston made of a magnetic material, which moves in the direction of an arrow 32 when an output signal of the computer 30 is input to the excitation winding 29, through a rod 33 made of a non-magnetic material,
The normally closed outlet 24 is opened against the force of the first spring 28. Reference numeral 34 is a second spring, which connects the rod 33 to the valve body 27.
Abut. The computer 30 inputs an operating parameter of the engine, for example, a carburetor throttle valve opening signal 35 and an oil temperature signal 36, calculates them, and performs duty control to open the normally closed outlet 24 of the three-way solenoid valve 21. The pulse current to be supplied is supplied to the excitation winding 29. FIG. 2 shows a structural example of the mechanical oil pump 20 used in the oil supply flow rate control device of the present invention. Reference numeral 1 is a housing, 2 is a cylinder, 3 is a plunger, and 4 is a cylinder.
Is a worm wheel formed on the plunger 3, 5 is a lead cam formed on one end of the plunger 3, and 7 is a tribing worm driven by an engine, as in the case of FIG. Hinge member for guiding the lead cam, 38 is a sub-cylinder bored in the plunger 2, 39 is a sub-plunger inserted in the sub-cylinder 38, 40 is a pump action chamber formed by the sub-cylinder 38 and the sub-plunger 39, and 41 is An oil inlet opening into the cylinder 2, 42 an oil outlet opening into the cylinder 2, 43
Is an oil passage that is formed in the plunger 3 and that alternately connects the pump action chamber 40 to the suction port 41 and the discharge port 42 by the rotational movement of the plunger 2. Reference numeral 44 is a spring that urges the flanger 3 in a direction to bring the lead cam 5 into contact with the pin member 37 and urges the sub-plunger 39 against the plunger 3 in a direction to increase the volume of the pump action chamber 40. When the driving worm 7 is driven by the engine, the engagement between the driving worm 7 and the worm wheel 4 causes the plunger 3 to move to the cylinder 2
While rotating in the air, the reed cam 5 and the pin member 37 make contact with each other to reciprocate, so that the oil passage 43 becomes the suction port.
When the plunger 3 is moved to the left in the figure by conducting to 41, the oil coming from the oil tank 26 is sucked into the pump action chamber 40, the oil passage 43 is conducted to the discharge port 42, and the plunger 3 is moved to the right. When moved, the oil in the pump action chamber 40 is discharged and the pump action is performed. Since the reciprocating stroke of the plunger 3 is constant, the mechanical oil pump 20 discharges oil at a flow rate proportional to the rotational speed of the engine.

FIG. 3 shows an example of the relationship between the oil discharge amount of the mechanical oil pump and the oil demand amount (oil supply amount) of the engine under a specific operating condition. The horizontal axis represents the engine speed and the vertical axis represents the engine speed. The flow rate of oil is taken and the code
45 indicates the discharge amount of the mechanical oil pump, which is proportional to the engine speed. When the engine rotation speed is n, the mechanical oil pump discharge amount is Qa, and when the engine oil demand is Qb, excess oil Qa-Qb is the normally closed outlet 24 side of the three-way solenoid valve 21. It is returned to the oil tank 26 by controlling the valve opening duty of. The computer 30 inputs and calculates, for example, the throttle valve opening signal 35 or the oil temperature signal 36, outputs a required pulse current for opening the normally closed outlet 24, and the excitation winding 29 of the three-way solenoid valve 21. The oil can be supplied to the engine at a flow rate suitable for the operating condition.

FIG. 4 shows that the ratio of the engine oil demand amount (therefore, the amount of oil supplied to the engine) Qb to the oil discharge amount Qa of the mechanical oil pump is the non-energization for the cycle a of the pulse current supplied to the excitation winding 29. It is a figure which shows that it is proportional to the ratio of time b. De-energized (OFF) over the entire cycle
When Qa = Qb, the full flow rate of oil discharged by the mechanical oil pump 20 is supplied to the engine, and when energized (ON) over the entire cycle, Qb = 0 and the oil is not supplied to the engine. Not supplied.

The mechanical oil pump 20 reliably and mechanically discharges oil proportional to the rotation speed of the engine, and the spring 28 of the three-way solenoid valve 21 is stronger than the spring 16 of the check valve of the electromagnetic pump, and is always protected by the intrusion of fine dust. There is no obstruction to the valve closing of the closed outlet, and even if an electrical failure occurs, the normally closed outlet remains closed, which acts on the safety side and cuts off the oil supply to the engine. There is no dripping.

[Advantages of the Invention] The oil supply flow rate control device of the present invention has the following features. Higher reliability than a pump. (2) Even if an electrical failure occurs, the oil supply increases, so there is no risk of engine seizure. (3) Engine operation It is possible to continuously control the oil having a flow rate suitable for the state by duty control.

There is an advantage to say.

[Brief description of drawings]

FIG. 1 is a diagram showing an oil supply flow rate control device of the present invention, FIG. 2 is a diagram showing a configuration example of a mechanical oil pump used in the oil supply flow rate control device of the present invention, and FIG. 3 is an oil discharge amount of the mechanical oil pump. FIG. 4 is a diagram showing the relationship with the oil demand of the engine in a specific engine operating state. FIG. 4 shows the ratio of the oil demand Qb of the engine to the oil demand Qa of the mechanical oil pump is the pulse supplied to the three-way solenoid valve. FIG. 5 is a diagram showing that it is proportional to the ratio of the non-energization time b to the current cycle a, and FIG. 5 shows the relationship between the throttle valve opening of the carburetor and the oil discharge amount by moving the discharge amount control cam shaft in the axial direction. FIG. 6 is a diagram showing the configuration of an oil pump proposed in Japanese Utility Model Application No. 62-163198, in which the relationship can be selected in two stages. FIG. 6 is an electromagnetic pump whose oil flow rate is controlled by a computer disclosed in Japanese Utility Model Application No. 62-33929. Diagram showing the configuration A. Explanation of code: 20 …… Mechanical oil pump, 21 …… Three-way solenoid valve, 22
...... Oil inlet, 23 ...... Normally open outlet, 24 ...... Normally closed outlet, 25 ...... Return passage, 26 ...... Oil tank, 27 ...... Valve element, 28 ...... First spring, 29 ...... Excitation coil, 30 ...
… Computer, 31… Piston, 33… Rod, 34…
… Second spring.

Claims (1)

[Scope of utility model registration request] 1. A three-way solenoid valve (21) has an inlet (22) mechanically connected to an engine and driven in association with the rotation of the engine to discharge oil at a flow rate proportional to the rotational speed of the engine. Mechanical oil pump (20) discharge port (4
2) is; in the normally open outlet (23) of the three-way solenoid valve (21),
An oil supply passage to the engine is provided; at the normally closed outlet (24) of the three-way solenoid valve (21), at the mechanical oil pump (2).
Oil tank (2) to which the suction port (41) of (0) is connected
The oil return passage (25) to 6) is connected; the signal output by the computer (30) inputting and calculating the operating parameter signal of the engine is the exciting winding (29) of the three-way solenoid valve (21). Input to the mechanical oil pump (2), the valve opening of the normally closed outlet (24) is duty controlled.
0) discharges excess oil to the oil tank (26) through the return passage (25) and supplies the engine with a flow rate of oil suitable for the operating condition. Flow control device.