JPH0227142Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to an improvement of an exhaust passage switching valve device for a multi-cylinder engine, and more specifically, to an improvement of an exhaust passage switching valve device for a multi-cylinder engine. The present invention relates to an improvement of an exhaust passage switching valve device provided in the exhaust passage of some of the cylinders of an engine which is used as an air compressor.

[Conventional technology]

Recently, the supply of fuel to some cylinders of a multi-cylinder engine installed in a vehicle has been stopped, and the exhaust passages of these cylinders have been closed using shutoff valves. A multi-cylinder engine is proposed in which the engine can be used as an air compressor by providing an exhaust passage switching valve device and taking out the compressed air obtained in the fuel supply stopped cylinder through the exhaust passage switching valve device. It is being

[Problems to be solved by the idea]

By the way, the exhaust passage switching valve device for a multi-cylinder engine configured as described above switches the exhaust passage using a device that uses high pressure air, and there is a gap between the piston and the cylinder of the piston device. An appropriate gap is provided so that the piston slides smoothly inside the cylinder, and high-pressure air leaks to the back side of the piston via this gap.

When the pressure of high-pressure air is applied to the piston, the piston pushes out the valve body attached to the piston, thereby communicating the exhaust passage with the compressed air take-off pipe. This piston ends its stroke when it hits the stopper, but since this stopper only determines the stroke of the piston, the high-pressure air eventually flows around from between the piston and the cylinder to the back side of the piston. There is a problem in that when the pressure is balanced with the front side, the piston returns to its original position and closes the compressed air outlet pipe.

In order to prevent this, a pressure difference is created between the front and back of the piston when the piston hits the stopper.
An air vent hole is provided in the cylinder on the back side of the piston, but this exhausts high-pressure air without limit, which may waste the high-pressure air in the air tank, lowering the air tank's internal pressure, and having a negative impact on other control equipment. There is.

[Purpose of invention]

The present invention was devised to overcome the above-mentioned problems with the exhaust passage switching valve device of the multi-cylinder engine that also serves as an air compressor.The purpose of this invention is to An exhaust gas for a multi-cylinder engine that can be operated as an air compressor to significantly reduce waste of high-pressure air due to leakage of high-pressure air from a piston device of an exhaust passage switching device, and prevent malfunction of the piston of the piston device. An object of the present invention is to provide a passage switching valve device.

[Means to solve the problem]

The exhaust passage switching valve device for a multi-cylinder engine according to the present invention which achieves the above object has an exhaust passage that can connect the exhaust passage of a cylinder in which fuel supply can be stopped in a multi-cylinder engine to a compressed air take-off pipe via a passage switching valve. The passage switching valve of the switching valve device is attached to the back side of a piston that is slidably fitted in the cylinder with a slight gap, and the front side of the piston of the cylinder is an electromagnetic three-way switching valve having an atmosphere communication port. is connected to a high-pressure air source via a piston, and the back side of the piston of the cylinder is connected to the atmosphere via a normally closed electromagnetic on-off valve that interlocks with the electromagnetic three-way switching valve,
A spring is disposed to urge the passage switching valve in its closing direction, and a sealing member is provided that engages an end of the piston to seal the back side of the piston of the cylinder when the piston reaches its final stroke position. It is characterized in that it is provided.

〔Example〕

Embodiments of the exhaust passage switching valve device for a multi-cylinder engine according to the present invention will be described below with reference to the drawings.

Figure 1 shows a V-type 8-cylinder engine 1 that can use 4 of the 8 cylinders as a compressor.
FIG. 2 is an explanatory diagram showing a state in which an exhaust passage switching valve device 10 according to an embodiment of the present invention is attached to a vehicle. In this example, cylinders C1, C3, C5, and C7 of the engine 1 are cylinders whose fuel supply can be stopped, and a line cutoff valve 3 is provided in the middle of the exhaust pipe 2 of these cylinders. The remaining C2, C4, C6, and C8 cylinders are always combustion cylinders.

The exhaust passage switching valve device 10 of the present invention is installed on the upstream side of this pipe line cutoff valve 3,
The exhaust pipe 2 can be communicated with a compressed air extraction pipe 4.

Reference numeral 5 denotes an air filter, and 6 is a powder tank mounted on a powder transport vehicle, for example, so that powder and granules such as powdered cement, sugar, and flour can be discharged and supplied through a duct 7 using compressed air. It is something that has become popular.

Passage switching valve 11 of the exhaust passage switching valve device 10
The switching connection of the pipe line is performed by a piston device 20, and the power source of this piston device 20 is the high pressure in a high pressure tank 8 mounted on the vehicle and connected by an air pipe 9 equipped with an electromagnetic three-way switching valve 31. It's air.

The electromagnetic three-way switching valve 31 is a well-known electrode three-way switching valve for passage switching, is disposed in the middle of the air pipe 9, has an atmosphere communication port 31a, and when not energized, the high pressure tank 8 The communication between the piston device 20 and the piston front side 22a of the piston device 20 is cut off. The piston front side 22a (FIG. 2) is communicated with the atmosphere through the atmosphere communication port 31a, and when energized, the high pressure tank 8 and the piston front side 22a are communicated.

Therefore, the electromagnetic fuel cutoff valve 36 disposed in the fuel pipe system FL closes, stopping the supply of fuel to cylinders C1, C3, C5, and C7, and the electromagnetic line cutoff valve 3 closes the exhaust pipe 2. , since the exhaust passage switching valve device 10 connects the exhaust pipe 2 and the compressed air take-off pipe 4, C1,
C3, C5, and C7 cylinders will act as compressors.

FIG. 2 is an enlarged sectional view showing details of the exhaust passage switching valve device 10 of the present invention.

An opening 2a is provided on the side surface of the exhaust pipe 2, and a flange 2b is provided on the periphery of the opening 2a, on which the exhaust passage switching valve device 1 is mounted.
0 is placed. This exhaust switching valve device 10
The main body casing 12 includes a main body casing 12 to which the compressed air take-off pipe 4 is connected to the side and has a passage switching valve 11 inside, and a main body casing 12 arranged above the main body casing to drive the passage switching valve 11 to switch the compressed air take-off pipe. A piston device 20 that communicates 4 with the exhaust pipe 2.
It consists of 13 is a valve seat of the passage switching valve 11, and 14 is a bushing for sealing the shaft portion 11a of the passage switching valve 11.

Further, the piston device 20 is arranged on an extension of the shaft portion 11a of the passage switching valve 11,
The end portion 11b of this shaft portion 11a is connected to the piston device 20.
The piston 22 is attached to the back surface of a piston 22 which is slidably fitted into the cylinder 21 with a slight gap 26. In this embodiment, the passage switching valve 11 is always connected to the piston by a spring 24 interposed between a spring bearing 23 attached near the shaft end 11b and the bottom wall 21a of the cylinder 21.
2 away from the bottom wall 21a, that is, in the closing direction of the passage switching valve 11, and as a result, the valve body 11c of the passage switching valve 11 and the valve seat 13 are pressed against the front side 22a of the piston. Unless applied, the exhaust pipe 2 and the compressed air take-off pipe 4 are kept in close contact with each other by the spring force so as not to communicate with each other.

Further, in this embodiment, a lid 25 is attached to the ceiling of the piston device 20, and an air pipe 9 is connected to a high-pressure air inlet 25a of the lid 25, and an electromagnetic three-way switching valve 31 (see FIG. ), the high-pressure air sent from the high-pressure tank 8 applies pressure to the front side 22a of the piston in the cylinder 21 and moves it toward the bottom wall 21a against the spring 24, thereby closing the valve of the passage switching valve 11. The body 11c is the valve seat 13
The exhaust pipe 2 and the compressed air take-off pipe 4 can be connected to each other by being separated from the exhaust pipe 2 and the compressed air take-off pipe 4.

By the way, the piston 2 of the piston device 20
2 and the cylinder 21, a slight space 26 is provided so that the piston 22 can move smoothly into the cylinder 21 as described above.
The high-pressure air flowing into the cylinder 21 from the air pipe 9 applies pressure to the front side 22a of the piston, and also slightly flows around the back side 22d of the piston.

Therefore, in the device of the present invention, a seal member 27 made of rubber or the like is provided on the stepped portion 21b of the cylinder 21 that determines the throat talk of the piston 22, so that the final stroke position of the piston 22, that is, the piston 2
2 is at a position where its movement can be stopped by the stepped portion 21b of the cylinder 21, and the end 22c of the piston 22 and the back side 22d of the piston are sealed to prevent high pressure air from flowing into the back side 22d of the piston.

Further, a communication hole 21c is provided in the lower part of the stepped portion 21b.
is formed, and the communication hole 21c is an air pipe 9 equipped with a normally closed electromagnetic on-off valve 32 that opens only when energized.
1, it is opened to the atmosphere.

Furthermore, as shown in FIG. 3, the electromagnetic on-off valve 32 is connected in series with the electromagnetic three-way switching valve 31, and is opened in conjunction with the opening of the electromagnetic three-way switching valve 31. It's getting old.

In FIG. 3, reference numeral 33 denotes a passage selector switch, which is connected to the battery 35 via a key switch 34, and is also connected to the electromagnetic line cutoff valve 3 and the electromagnetic fuel cutoff valve 36 in addition to the electromagnetic valves 31 and 32. has been done.

In the exhaust passage device configured as described above, when the passage selector switch 33 is closed, the electromagnetic on-off valve 32 is opened together with the electromagnetic three-way switching valve 31, so that the piston front side 22a inside the cylinder 21 is opened.
High pressure air is introduced into the piston back side 2.
2d is opened to the atmosphere. Shigatate cylinder 2
Even if high-pressure air flows out to the back side of the piston 22d through the space between slides smoothly (downward in Figure 2), and the exhaust pipe 2
is communicated with the compressed air take-off pipe 4.

When the piston 22 reaches its final stroke position, the end 22c of the piston 22 is connected to the sealing member 27.
The high-pressure air that is pressed by the piston does not leak from the front side 22a of the piston to the back side 22d, and wasteful consumption of high-pressure air is therefore significantly reduced.

Furthermore, at this time, the back side 22d of the piston of the cylinder 21 is open to the atmosphere via the electromagnetic on-off valve 32, so the opening operation of the passage switching valve 11 is also stabilized.

Here, if the passage selector switch 33 is opened, the electromagnetic three-way selector valve 31 will open the piston front side of the cylinder 21.
2a to the atmosphere through the atmosphere communication port 31a, the piston 22 and passage switching valve 11 slide smoothly (upward in FIG. 2), thereby establishing communication between the exhaust pipe 2 and the compressed air outlet pipe 4. Stop.

[Effects of the invention] As explained above, the exhaust passage switching valve device for a multi-cylinder engine of the invention does not allow the piston to move when the passage switching valve is fully open and the exhaust pipe and the compressed air take-out pipe are in communication. The high-pressure air that is being driven flows through a small space between the piston and the cylinder and does not flow from the front side of the piston to the back side. Moreover, since the back side of the piston is maintained at atmospheric pressure, the pressure difference between the front and back of the piston is reduced, eliminating the return of the piston and the leakage of high-pressure air required to open the piston, resulting in malfunction of the piston and waste of high-pressure air. This has the effect of significantly reducing

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the installed state of the exhaust passage switching valve device of the present invention installed on a variable cylinder number engine, Fig. 2 is an enlarged view showing the detailed structure of the exhaust passage switching valve device of the invention, and Fig. 3 The figure is a control circuit diagram of the exhaust passage switching device of the present invention. 2...Exhaust pipe, 3...Solenoid pipe cutoff valve, 4...
Compressed air take-off pipe, 10...exhaust passage switching device, 1
1... Passage switching valve, 12... Casing, 20...
...Piston device, 21...Cylinder, 21c...
Communication hole, 22...Piston, 22a...Piston front side, 22c...Piston end, 24...Spring, 26...Between, 27...Sealing member, 31...
...Solenoid three-way switching valve, 32...Solenoid on-off valve, 33...
...Aisle changeover switch.

Claims (1)

[Scope of utility model registration request] The passage switching valve of the exhaust passage switching valve device is capable of connecting the exhaust passage of a cylinder to which fuel supply can be stopped in a multi-cylinder engine to a compressed air take-off pipe via a passage switching valve, and the passage switching valve has a slight gap inside the cylinder. The front side of the piston of the cylinder is connected to a high-pressure air source via an electromagnetic three-way switching valve having an atmosphere communication port, and the back side of the piston of the cylinder is connected to the electromagnetic A spring is provided which is connected to the atmosphere through a normally closed electromagnetic on-off valve that operates in conjunction with the three-way switching valve, and which biases the passage switching valve in its closing direction, and when the piston has reached its final stroke position. An exhaust passage switching valve device for a multi-cylinder engine, which is provided with a sealing member that seals the back side of the piston of the cylinder when the end of the piston engages with the piston end.