JPS5925020A - Valve stopping device of variable displacement type engine - Google Patents

Abstract

PURPOSE:To perform rapid switching of operation and non-operation without malfuction, by mounting a check ball in a high-pressure chamber and installing a rod, operated by an electromagnetic mechanism, to a low-pressure chamber. CONSTITUTION:During usual operation, a hydraulic oil is fed through the working of a pump 27 by forcibly pushing down a check ball 19 in a high-pressure chamber 14, the check ball 19 closes a valve seat 15 with a difference in pressure between the high-pressure chamber and a low-pressure chamber 13 through which the hydraulic oil is discharged to a discharge passage 31, a hydraulic tappet 9 is secured, and a suction and exhaust valve 6 is vertically moved through rotation of a cam 10. When a cylinder reducing switch 26 is turned ON, a shut-off valve 30 cuts the supply of hydraulic oil through a pump 27, and simultaneously, a rod 23 of a solenoid 22 forcibly presses down the check ball 19 to interconnect the high-pressure chamber 14 and the low-pressure chamber 13. As a result, even if the cam 10 turns, the hydraulic tappet 9 is raised to prevent the vertical movement of the cam 10 from being transferred to a locker arm 4, and the suction and exhaust valve 6 is brought to an inoperative state.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable displacement engine that can change the number of operating cylinders of the engine, and in particular stops the operation of the pulp corresponding to the cylinder to which fuel supply has been stopped. This reduces the load on the engine, and
This invention relates to a valve stop device for a variable displacement engine that can reliably stop pulp operation.

In general, variable displacement engines reduce the number of cylinders to which fuel is supplied depending on the engine operating conditions, reducing the operating displacement and also stopping the operation of the valves corresponding to the cylinders to which fuel supply has been stopped, reducing fuel consumption. It is widely known to reduce

In recent years, fuel efficiency has become a very important factor in choosing a car, and it has attracted particular attention.

Conventionally, the valve stop device for the above-mentioned variable displacement engine has been a two-part rocker arm, in which the rocker arm is divided into a camshaft side and an intake/exhaust valve side, and the two can be integrated or separated by inserting and removing a key. There was also a hydraulic tappet type in which the tappet was divided into upper and lower halves, hydraulic pressure was applied between them to allow normal operation, and the hydraulic pressure was released to disable the tappet.

However, the type that splits the rocker arm into two has the drawback that it is difficult to adjust the timing of inserting and removing the key.

Also, although the hydraulic tappet type has a faster switching response than the type with a two-part rocker arm, the tappet is activated and deactivated by controlling the pump oil pressure. There is a problem in that various parts must be incorporated to make the discharge pressure variable.

In recent years, there has been a demand for the above-mentioned hydraulic tappet type engines to be highly reliable and free from erroneous movements.

This invention was devised by paying attention to such conventional problems, and its purpose is to provide a hydraulic tappet type for an overhead valve type internal combustion engine, which has quick switching response between activation and deactivation. The present invention also provides a valve stop device for a variable displacement engine that does not require variable control of oil pressure and operates reliably without error movement.

In order to achieve the above-mentioned object, the present invention provides a valve operating mechanism for a valve stop device that opens and closes intake and exhaust valves using a rocker arm of an overhead valve type internal combustion engine, the valve operating mechanism having a bushing rod at the tip thereof. A high-pressure chamber is equipped with a sliding body with a concave cross section that can be raised and lowered along a tappet housing formed in the cylinder body, and a pressure oil supply/discharge port is provided through a plunger having an orifice passage inside the sliding body. and a low-pressure chamber, a check ball is installed in the high-pressure chamber and is always biased in a direction to close the orifice passage, and the low-pressure chamber is operated by an electromagnetic mechanism,
The gist is that a rod is provided to press the check ball, and the electromagnetic mechanism is excited to press the check ball via the rod, thereby discharging pressurized oil in the high pressure chamber to the low pressure chamber side. be.

Hereinafter, the present invention will be described in detail based on the accompanying drawings.

The figure shows a cross-sectional view of a valve stop device for an overhead valve type internal combustion engine, in which 1 is a cylinder head, 2 is a cylinder body, and a rocker arm 4 swings through a rocker arm shaft 3 to the cylinder head 1. It is freely supported.

An intake/exhaust valve 6 for opening/closing the intake/exhaust passage 5 formed in the cylinder head '1 is provided on one end side of the locking arm 4.
The top edges of the two are in contact with each other. The intake/exhaust valve 6 is always biased via a spring 7 in a direction to close the intake/exhaust passage 5.

On the other hand, the other end of the rocker arm 4 is in contact with a cam 10 that is pivotally supported on the cylinder body 2 via a bushing rod 8 and a hollow cylindrical hydraulic tappet 9 as a sliding body connected thereto.

The hydraulic tappet 9 is slidably housed in a tappet housing 11 formed in the cylinder body 2, and a hydraulic oil supply/discharge port tt is provided on the inner wall of the tappet housing 11.
a, fib is formed. Inside the hydraulic tappet 9, there are a low pressure chamber 16 communicating with the supply port 11a via the plunger 12, and a high pressure chamber 1 communicating with the discharge port 11b.
4 are partitioned.

An orifice passage 16 having a valve seat 15 is bored in the lower wall of the plunger 120, and a spring 18 is biased between the mesh spring retainer 17 attached to the valve seat 15 and the valve seat 15. A check ball 19 serving as a closed valve is interposed to close the valve seat 15.

Further, a spring 20 is interposed between the lower wall of the plunger 12 and the hydraulic tappet 9.

Furthermore, a spring 21 is interposed inside the low pressure chamber 16 to always urge the plunger 12 downward, and the bush rod 8 is connected to the earthen wall of the low pressure chamber 13.

A solenoid 22 as an electromagnetic mechanism is provided in the upper part of the low pressure chamber 16, and a rod 23 whose tip is directed toward the check ball 19 is provided on the solenoid 22 so as to be movable up and down.

The connection wire 2 connecting the solenoid 22 and the power supply 24 is still connected.
A cylinder reduction switch 26 is interposed at 5. A cutoff valve 30 is connected between the cylinder reduction switch 26 and the solenoid 22 and is interposed in a supply passage 29 that connects the supply port 11a and the oil pan 28 tangential to the pump 27.

Further, the oil pan 28 and the discharge port 11b are connected through a discharge passage 61.

In the above configuration, first, during normal operation of the engine, hydraulic oil in the oil pan 28 is supplied from the supply passage 29 by pushing down the check ball 19 of the high pressure chamber 14 via the pump 27, and the hydraulic oil is supplied to the discharge passage 31. Due to the pressure difference between the check ball 19 and the low pressure chamber 13 from which the
The valve seat 15 is closed, the hydraulic tappet 9 is fixed, and the cam 1
0 rotation causes the intake and exhaust valve 6 to perform normal vertical movement.

Next, for example, when the engine load decreases and the cylinder reduction switch 26 is turned ON, the cutoff valve 30 cuts off the hydraulic oil supply to the pump 27, and at the same time, the solenoid 22 is energized and the rod 26 is connected to the check ball. 19 is pushed down to connect the high pressure chamber 14 and the low pressure chamber 16.

Then, in this state, the cam 10 rotates, and the hydraulic tappet 9
When is pressed upward, hydraulic oil flows from the high pressure chamber 14 to the low pressure chamber 16, and is discharged from the discharge port 11b of the low pressure chamber 16, which causes the hydraulic tappet 9 to rise and the cam 10 to open. The vertical movement is not transmitted to the rocker arm 4, and the intake and exhaust valves 6 do not operate.

When the engine is loaded again, the cylinder reduction switch 26 is turned OFF, hydraulic oil is supplied to the high pressure chamber 14 via the pump 27, and the intake and exhaust valves 6 resume normal operation via the rocker arm 4 as described above. do.

As described above, the present invention is a valve operating mechanism for a valve stop device that opens and closes intake and exhaust valves using a rocker arm of an overhead valve type internal combustion engine, the valve operating mechanism having a cylinder body attached to the tip of a bushing rod of the valve operating mechanism. A sliding body with a concave cross section that can be raised and lowered along the formed tappet housing is installed,
A high-pressure chamber and a low-pressure chamber each having a pressure oil supply/discharge port are formed through a plunger having an orifice passage inside the sliding body. At the same time, a rod operated by an electromagnetic mechanism to press the check ball is provided in the low pressure chamber, and the electromagnetic mechanism is energized to press the check ball via the rod, thereby increasing the pressure in the high pressure chamber. By discharging pressure oil to the low pressure chamber side, there is no need to use a variable discharge pressure pump to change the pump oil pressure as in the past, and the tappet housing of the existing overhead valve type engine can be modified slightly. It can be easily made into a variable displacement engine, and has the effect of improving fuel efficiency.

In addition, since there are almost no changes to the main parts of the existing engine, there is the advantage that the reliability and performance of the engine remain the same.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall schematic explanatory diagram of a valve stop device, and FIG. 2 is an enlarged sectional view of the main part. 2... Cylinder body, 4... Rocker arm,
6... Intake and exhaust valve, 8... Bush rod, 9...
Hydraulic tappet, 11... Tappet housing, 11a
, 11b... Supply/discharge port, 12... Plunger, 1
3...Low pressure chamber, 14...High pressure chamber, 16...Orifice passage, 19...Check ball, 22...Solenoid, 23...Rod. Agent: Patent Attorney Shin Ogawa − Patent Attorney Ken Noguchi Teru Patent Attorney Kazuhiko Saishita

Claims (1)

[Claims] A valve operating mechanism of a valve stop device that opens and closes intake and exhaust valves using a rocker arm of an overhead valve type internal combustion engine, the valve operating mechanism having a bushing rod at the tip of the valve operating mechanism that moves up and down along a tappet housing formed in a cylinder body. A sliding body with a flexible concave cross section is installed, and a high pressure chamber and a low pressure chamber are defined, each having a pressure oil supply/discharge port via a plunger having an orifice passage inside the sliding body. The chamber is equipped with a check ball that is always biased in the direction of closing the orifice passage, and the low pressure chamber is equipped with a rod that is operated by an electromagnetic mechanism to press the check ball, and the electromagnetic mechanism is energized to press the check ball. 1. A valve stop device for a variable displacement engine, characterized in that the valve stop device for a variable displacement engine is configured to press a check ball through the valve to discharge pressurized oil in a high pressure chamber to a low pressure chamber side.