JPH0234402Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention relates to an intake/exhaust valve operation stop device, and more specifically, the present invention relates to an intake/exhaust valve actuation stop device. The present invention relates to an intake/exhaust valve operation stopping device that uses a hydraulic mechanism to stop the operation of the intake/exhaust valve of the interrupted cylinder. [Prior Art] As is well known, in an internal combustion engine having multiple cylinders, fuel injection to some of the cylinders, for example, 4 out of 8 cylinders, is interrupted when the load is below a set load, and fuel injection to the other 4 cylinders is interrupted. Extra fuel is injected into the cylinders to increase thermal efficiency and ultimately reduce fuel consumption. [Problem that the invention aims to solve] By the way, when fuel injection is interrupted, if the intake and exhaust valves in that cylinder are operating normally, the intake and exhaust pump work due to air flowing in and out of that cylinder will naturally occur. Compression work is performed by compressing the air that has flowed into the cylinder. That is, the fact that these cylinders perform pump work and compression work means that the cylinders to which fuel injection is being continued bear the load. Therefore, if the work as the load can be eliminated, fuel consumption can be further reduced. For this reason, when fuel injection to some cylinders of a multi-cylinder engine is interrupted, a tappet, for example, is used as an intake/exhaust valve operation stop device for the purpose of stopping the operation of the intake/exhaust valve of the cylinder where fuel injection is interrupted. Hydraulic bushing rods that can be separated into one piece using hydraulic pressure, such as hydraulic tappets that divide the cylinder and piston into two and apply hydraulic pressure between them to allow the intake and exhaust valves to operate normally and release the hydraulic pressure to make them inactive. A hydraulic mechanism such as a hydraulic rocker arm has been proposed. However, in the intake/exhaust valve operation stop device using the above-mentioned hydraulic mechanism, the hydraulic pressure control timing is different, and when the intake/exhaust valve is activated, the intake/exhaust valve moves differently from the movement due to the shape of the cam. This method has the disadvantage that the opening and closing timing of the valve is inconsistent, causing various problems. Therefore, the purpose of the present invention is to eliminate the above-mentioned conventional drawbacks.The purpose of this invention is to use an intake/exhaust valve operation stop device that stops the intake/exhaust valve and resumes operation only during the base circle of the cam (when the intake/exhaust valve is closed). By doing so, it is possible to prevent the timing of opening and closing of the intake and exhaust valves from being out of order. [Means for Achieving the Object] The intake and exhaust valve operation stop device of the present invention to achieve the above object includes an intake and exhaust valve stop mechanism for an engine with a variable number of cylinders, an intake and exhaust valve operation stop switch, and an intake and exhaust valve operation stop switch. A valve opening/closing timing detector is provided, and the valve closing signal of the detector and the operation stop signal of the switch are combined into a first AND signal.
The valve closing signal of the detector and the inverted operation stop signal of the switch are applied to a second AND circuit, and a second AND circuit is applied to the set terminal of the flip-flop circuit.
Apply the output signal of the 1AND circuit and connect the reset terminal to the
It is equipped with a valve stop mechanism control circuit that provides the output signal of the 2AND circuit and outputs the output signal of the output terminal to the intake and exhaust valve stop mechanism. [Example] An example of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram of the configuration of an embodiment of the intake/exhaust valve operation stop device of the present invention. In this embodiment, as a hydraulic mechanism, the tappet body 1e that contacts the cam 3 and the push rod 4 are brought into contact with each other, and the tappet body 1 is brought into contact with the push rod 4.
A hydraulic tappet 1 consisting of a plunger 1f and a plunger 1f fitted into the tappet e is used. When the interior 1a of the hydraulic tappet 1 is filled with the lubricating oil L in the oil pan 2 by the oil pump 7, the lift movement of the intake and exhaust valves of the cam 3 moves through the hydraulic tappet 1, the push rod 4, and the rocker arm 5. or exhaust valve 6
However, when the lubricating oil in the interior 1a of the hydraulic tappet 1 is in the discharged state, the spring 1g in the interior 1a of the hydraulic tappet 1 absorbs the lift motion of the cam 3 and does not transmit it to others, so the suction or exhaust valve 6 is no longer working. The intake/exhaust valve stop mechanism of this embodiment is composed of the hydraulic tappet 1 and an electromagnetic switching valve 8 for operating the hydraulic tappet 1. That is, the electromagnetic switching valve 8 controls the supply and discharge of hydraulic oil to the hydraulic tappet 1, and this electromagnetic switching valve 8 connects the oil passage 1b and the oil discharge passage 1c with an on signal "H" (high level). The lubricating oil in the hydraulic tappet 1 is continuously discharged, that is, the intake and exhaust valves 6 are stopped,
In response to the off signal "L" (low level), the oil passage 1b is connected to the oil supply passage 1d, lubricating oil L is supplied from the oil pump 7 to the hydraulic tappet 1, and the intake and exhaust valves 6 are activated. In the present invention, the electromagnetic switching valve 8 is connected to the outlet terminal Z of the valve stop mechanism control circuit 10, and the input terminals X and Y of the valve stop mechanism control circuit 10 are connected to an intake/exhaust valve operation stop switch 9 and a valve opening/closing timing switch, respectively. A detector 20 is connected. When the intake/exhaust valve operation stop switch 9 is turned on, the input terminal Y becomes high level "H", and the valve opening/closing timing detector 20 detects the position where the cam 3 closes the intake or exhaust valve 6 (the cam nose 3a is pointing downward in the figure). base circle), it outputs a high level "H" as a valve closing signal, and sets the input terminal X to a high level "H".
That is, a contact 21 that operates in conjunction with the cam 3 is connected to the power supply and input terminal X, and the other is connected to the ground.
Therefore, a voltage is applied to the input terminal X when the cam 3 is on the base circle. In this embodiment, the valve stop mechanism control circuit 10 includes a first AND circuit 11 (hereinafter simply referred to as AND circuit 11) and a second AND circuit 1 having one inverting input.
2 (hereinafter simply referred to as the AND circuit 12) and the output terminal of the AND circuit 11 through the set terminal S.
It consists of a flip-flop 13 connected to the output terminal of the circuit 12 through a reset terminal R, and an output amplifier 14 connected to the output terminal Q of this flip-flop 13, and the input terminal X is connected to the AND circuit 1.
1 and 12, respectively, and the input terminal Y is connected to the input terminal of AND circuit 11 and AND circuit 1.
The output terminal Z is connected to the output terminal of the output amplifier 13. The intake/exhaust valve operation stop device of the present invention can be used, for example, for a period when the intake/exhaust valve is in the "closed" state, as shown in FIG.
When the intake/exhaust valve operation stop switch is turned on or off at T ₁ and T ₂ , the hydraulic tappets are simultaneously separated and integrated by the electromagnetic switching valve, but during the time period T ₃ , when the intake/exhaust valve is in the “open” state, Even if the intake/exhaust valve operation stop switch is turned on or off at T ₅ , the hydraulic tappet will operate so as not to separate or integrate until the intake/exhaust valves are in the "closed" state at times T ₄ and T ₆ . It's summery. This operation will be explained using the configuration explanatory diagram of this embodiment shown in FIG. 1 and the operation waveform diagram of each part in FIG. 1 shown in FIG. First, the valve opening/closing timing detector 20 detects whether the intake or exhaust valve

[Effect of idea]

As explained above, the intake/exhaust valve operation stop device of the present invention operates the intake/exhaust valve stop mechanism that switches the intake/exhaust valve between operation and non-operation only when the intake/exhaust valve is closed. This has the effect that even if the number of operating cylinders is changed, the opening/closing timing of the intake and exhaust valves does not vary. In addition, in this embodiment, control of only one intake or exhaust valve has been explained, but check the cylinder switching timing of other stoppable cylinders, and if there is a cylinder that has good timing at the same timing, it can be controlled by one valve opening/closing timing detector. It becomes possible to control multiple intake or exhaust valves.

[Brief explanation of drawings]

Fig. 1 is a configuration explanatory diagram of an embodiment of the intake/exhaust valve operation stop device of the present invention, Fig. 2 is an operating state diagram showing the operation of the main components of the device of this embodiment, and Fig. 3 is the same as Fig. 1. FIG. 3 is an operation waveform diagram of each part. 1...Hydraulic tappet (intake/exhaust valve stop mechanism), 3
...Cam, 6...Suction or exhaust valve, 7...Oil pump, 8...Solenoid switching valve (intake/exhaust valve stop mechanism),
9... Intake and exhaust valve operation stop switch, 10... Valve stop mechanism control circuit, 11... AND circuit (1st AND
circuit), 12...AND circuit (second AND circuit), 1
3...Flip-flop, 20...Valve opening/closing timing detector, Q...Output terminal, R...Reset input terminal, S...Set input terminal.

Claims (1)

[Scope of utility model registration request] An intake/exhaust valve stop mechanism for an engine with a variable number of cylinders, an intake/exhaust valve operation stop switch, and a valve opening/closing timing detector for the intake/exhaust valves are provided, and the valve closing signal of the detector and the operation stop signal of the switch are detected. Give it to the 1AND circuit,
The valve closing signal of the detector and the inverted signal of the stop signal of the switch are applied to a second AND circuit, the output signal of the first AND circuit is applied to the set terminal of the flip-flop circuit, and the output signal of the second AND circuit is applied to the reset terminal of the flip-flop circuit. An intake/exhaust valve operation stop device equipped with a valve stop mechanism control circuit that outputs an output signal from an output terminal to an intake/exhaust valve stop mechanism.