KR940010284B1 - Valve driving apparatus of an internal combustion engine - Google Patents

Abstract

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Description

Valve driving device of internal combustion engine

1 is a system diagram of a valve driving apparatus according to an embodiment of the present invention.

2 is a system diagram of a conventional accumulator valve driving device.

* Explanation of symbols for main parts of the drawings

2: intake and exhaust valve 5: air piston

6: air cylinder 9: operating piston

11: open side logic valve 13: open side sprue control valve

14: closed side logic valve 15: closed side sprue control valve

16: accumulator 17: hydraulic pressure source

The present invention relates to a valve driving apparatus of an internal combustion engine of the type which opens and closes an intake / exhaust valve by an actuator.

An example of a conventional accumulator valve driving device is shown in FIG. In the configuration, (01) is a hydraulic control valve body, and has five holes. Reference numeral 02 is a control valve, which is driven in synchronism with the crankshaft of the engine by the cam 03 and the roller 04. Intake and exhaust valves 07 open and close inside the actuator 06 mounted on the cylinder cover 05. The actuator 06 has an upper hydraulic chamber 06a and a lower hydraulic chamber 06b, and is connected to the control valve 01 by pipes 08 and 09, respectively. Reference numeral 010 denotes a hydraulic pressure supply device consisting of a filter and a pump, and 010a denotes an oil tank. As the accumulator, it is maintained at the required constant hydraulic pressure and communicates with the control valve 01 in a pipeline.

Next, the operation will be described. In the figure, the roller 04 is located at the base of the cam 03, and the intake / exhaust valve is closed. The hydraulic oil from the accumulator 011 passes through the pipe 09 from the control valve 01. Thus, it acts on the lower hydraulic chamber 06b of the actuator, and pushes the intake and exhaust valve 07 upward. At this time, the oil in the upper hydraulic chamber 06a is delivered to the tank 010a of the hydraulic pressure source 010 via the piping 08 and the control valve 01 and returned.

When the cam 03 rotates and the roller 04 lifts, the oil in the lower hydraulic chamber 04b of the actuator 06 is discharged to the tank 010a via the pipe 09 and the control valve 01. At the same time, the high pressure hydraulic fluid of the accumulator 011 is led to the upper hydraulic chamber 06 of the actuator 06 through the control valve 01 and the pipe 08 to push down the intake / exhaust valve 07 to open the valve. Let's do it. When the cam 03 rotates and the lift of the cam decreases to reach the base circle, the oil in the upper hydraulic chamber 06a falls into the tank 010a, and the hydraulic oil in the accumulator 011 lowers the hydraulic chamber 06b. In operation, the intake and exhaust valves 07 are raised and closed upwards.

The prior art described above has the following problems.

The control valve 01 has five holes, the structure is complicated, and the flow rate required for opening and closing the intake and exhaust valves must also flow in the control valve section, and the hydraulic device becomes large.

Moreover, it has two piping 08 and 09 for opening and closing a high pressure flow path valve, and the structure of an actuator is complicated, and consumption of a high pressure oil is large, and therefore, a lot of power is consumed.

In addition, the control valve 01 is driven by the cam 03, so that the opening and closing time of the intake / exhaust valve can be changed freely.

The high pressure hydraulic fluid is used only for opening the valve of the intake and exhaust valve, and the valve closing is performed by the elastic force generated by the release of the elastic energy stored in the elastic mechanism in accordance with the lift of the intake and exhaust valve.

In addition, two control valves and two logic valves are arranged, and the control valve is electrically driven to control the hydraulic action from the accumulator to the large diameter portion of the logic valve. The oil is caused to act on the piston of the cylinder in the valve drive actuator via one logic valve and one high pressure pipe from the accumulator.

In addition, the small diameter sides of the two logic valves are in communication with each other. When the valve is closed, the other logic valve is opened to release the hydraulic pressure in the cylinder and the high pressure pipe.

The high pressure hydraulic fluid accumulated in the accumulator acts on the piston of the cylinder in the valve drive actuator when the open side logic valve is opened by the open side control valve electrically driven at any time, and pushes down the intake / exhaust valve. After that, the closing control valve is returned and the opening logic valve is closed. The intake / exhaust valve continues to open the valve by hydraulic pressure, but the compression force of the air by the air piston cylinder driven together with the intake / exhaust valve acts as an elastic force in the valve closing direction, and is maintained at a proper lift by balance with the hydraulic pressure. When the intake and exhaust of the engine is made, the closing logic valve opens by the closing control valve, and since the inflow is released, the intake and exhaust valve is closed by the air elastic force.

This cycle is repeated.

An embodiment of the present invention will be described with reference to FIG. (1) cylinder cover, (2) intake / exhaust valve, (3) air tank, (4) check valve. Denoted at 5 is an air piston, which slides inside the air cylinder 6 at the same time as the intake / exhaust valve 2. (7) is the valve actuator actuator body (8) is a hydraulic cylinder (9) is an operating piston, (8a) is an upper hydraulic chamber, (8b) is a lower hydraulic chamber.

Denoted at 10 is a high pressure pipe, 11 at an open logic valve, and 12 at an open logic valve flow path, which is connected to the accumulator 16. Numeral 13 denotes an open sprue control valve, which is driven at the same time as the crank rotation of the engine by a controller (not shown). Numeral 14 denotes a closed logic valve, and numeral 15 denotes a closed valve control valve, which is driven by a controller not shown in the same manner as the open valve control valve 13, and has three port ports. to be. Numeral 16 denotes an accumulator, and numeral 17 denotes a hydraulic pressure source device for supplying high pressure oil, and is composed of a pump and a filter. Numeral 18 denotes a low pressure hydraulic source device, which is in communication with the valve drive actuator 7 by way of a conduit 18a. (19) is an oil tank, (20) is a communication flow path connecting the open logic valve and the closed logic valve, (21) a flow path connecting the large diameter side of the open logic valve and the open sprue control valve, Denoted at 22 is a flow path connecting the open-side sprue control valve 13 and the accumulator 16, and 23 at the large-diameter side of the closed-side logic valve 14 and the closed-side spout control valve 15. A flow path for connecting 24 is a flow path for connecting the closed-side spun control valve 15 and the accumulator 16.

Numeral 25 denotes an oil pipe from the closed logic valve 14 to the oil tank 19, and numeral 26 denotes an oil pipe from the spun control valves 13 and 15.

The spoof control valves 13 and 15 are three-pot control valves which are electronically driven by having P pots, C pots, and T pots.

Next, the operation of the apparatus will be described.

In this figure, the air pressure of the air tank 3 acts on the lower part of the air piston 5, and the intake / exhaust valve 2 is closed.

At this time, the opening and closing sprue control valves 13 and 15 act on the hydraulic pressure from the accumulator to the large diameter side of the open and close logic valves 11 and 14, thereby providing a logic valve 11. (14) is closed.

When the intake / exhaust valve 2 is open at the valve opening time, the opening sprue control valve 13 is operated at a suitable time judged by a computer by the trigger signal transmitted in synchronization with an engine (not shown) and by the operating state of the engine. ) Is driven. When the copper control valve 13 is operated, the flow passage 22 is closed, and the flow passage 21 passes through the oil supply pipe 26 so that the hydraulic pressure of the large diameter side of the logic valve 11 is released. This opens, and the hydraulic pressure of the accumulator 16 acts on the upper hydraulic chamber 8a of the hydraulic cylinder 8 in the valve drive actuator 7 from the flow passage 12 and the high pressure pipe 10. The hydraulic piston 9 is pushed down by this hydraulic pressure, and the intake / exhaust valve 2 is opened.

At this time, the air in the air cylinder 6 is compressed, and the intake / exhaust valve 2 lifts to the point where the upward force acts on the air piston 5 and the force balances with the downward force by the hydraulic pressure.

Thereafter, the open side control valve 13 is returned, and the hydraulic pressure of the accumulator 16 acts on the large diameter portion of the logic valve 11, so that the open side logic 11 is closed.

When the intake and exhaust of the engine is made, the closed side spun control valve 15 is driven to close the flow passage 24, and the flow passage 23 is connected to the drain pipe 26, so that the logic valve 14 Since the hydraulic pressure of the large diameter side is removed, the logic valve 14 is opened, and the hydraulic pressure acting on the upper hydraulic chamber 8a is discharged from the high pressure pipe 10 and the communication flow path 20 to the oil pipe 25. The hydraulic force is lost. Then, the intake / exhaust valve closes by the elastic force by the compression of the air acting on the air piston 5. At this time, oil is supplied from the low pressure hydraulic source 18 to the lower hydraulic chamber 8b, and the working piston 9 returns to the lifted position in a stable state without the occurrence of voids.

In addition, although the return device of the intake / exhaust valve by air spring was shown in the said Example, it can also use with a conventional coil spring.

The valve drive device of an internal combustion engine which has a hydraulic pressure source and an accumulator which pressurizes and accumulates hydraulic fluid, controls the hydraulic fluid of an accumulator, and drives an intake / exhaust valve, which communicates with an upper portion of a piston for driving an intake / exhaust valve. Two mutually connected logic valves for opening and closing the high pressure flow passage, and two electromagnetically driven control valves for controlling the opening and closing of the two logic valves, the control hydraulic pressure for opening and closing the logic valves and the intake and exhaust valves are opened. The hydraulic oil to be driven is supplied from a high pressure accumulator, and the intake and exhaust valves are closed by the elastic force accumulated in accordance with the lift of the valve opening of the intake and exhaust valve driving piston.

(1) Since the valve opening and closing characteristic of the intake / exhaust valve can be obtained optimally for the engine, it is a high-performance engine with low fuel consumption.

(2) Since the high pressure oil consumption for valve driving is small, the hydraulic pressure source can be designed small, resulting in a low price. In addition, it consumes less power and has a lower fuel consumption.

(3) Since the flow rate in the control valve portion is minimized, a compact control valve can be realized, and a device with good reliability and durability can be realized.

Claims (1)

In a valve driving apparatus of an internal combustion engine that has a hydraulic pressure source and a accumulator that pressurizes and accumulates hydraulic fluid, and controls the hydraulic oil of the accumulator, driving the intake / exhaust valve, opening and closing the high-pressure flow passage communicating with the upper portion of the intake / exhaust valve driving piston. Two mutually connected logic valves, and two solenoid-driven spun control valves for controlling the opening and closing of the two logic valves, and controlling the hydraulic pressure for opening and closing the logic valves and opening and closing the intake / exhaust valves. Means for supplying hydraulic oil from a high-pressure accumulator and closing the intake / exhaust valve by an elastic force accumulated according to the lift of the valve opening of the intake / exhaust valve driving piston, and closing the intake / exhaust valve by the elastic force. The means slides and moves in the air cylinder by the air cylinder and the piston for driving the intake and exhaust valves. Valve driving device of an internal combustion engine, characterized in that consisting of an air piston for generating an air elastic force.