JP2591091Y2 - Pneumatic circuit device for automatic transmission - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic circuit device of an electronically controlled automatic transmission having a shift cylinder and a select cylinder, and having a magnetic valve for operating the shift cylinder and the select cylinder.

[0002]

2. Description of the Related Art For example, among mechanical electronically controlled transmissions for electronically operating a mechanically variable transmission, a mechanically electronically controlled transmission having three magnetic valves on each of a shift side and a select side is known. I have. However, the three magnetic valves on the shift side (eg A, B, C)
One of the main magnetic valves of the shift
If any one of the magnetic valve C for controlling the position of the gear A and the neutral position is running, that is, in a state where it is in one of the shift stages and fails to operate, it is dangerous to return to the neutral position. .

Japanese Utility Model Laid-Open Publication No. Sho 62-139833 discloses a case in which, after a clutch for operating an air cylinder is engaged, a solenoid valve provided in a circuit of the air cylinder is turned off to release the air cylinder to the atmosphere. If the solenoid valve remains off due to a failure of the solenoid valve, there is a problem that the vehicle jumps out. For this purpose, a technique using a normally closed solenoid valve has been disclosed. However, such a known technique cannot be applied to a magnetic valve that is controlled to a neutral position because the air circuit is different.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to operate a shift cylinder in an electronically controlled automatic transmission having a shift cylinder and a select cylinder, and having a magnetic valve for operating the cylinder. It is an object of the present invention to provide a pneumatic circuit device of an automatic transmission capable of performing a neutral set even if a magnetic valve that fails becomes inoperable due to a failure.

[0005]

According to the present invention, there is provided a pneumatic circuit device for an electronically controlled automatic transmission having a shift cylinder and a select cylinder, and having a magnetic valve for operating the cylinders. A piston (4) for controlling a neutral is slidably fitted into one end of the cylinder (1), and a port () provided at one end of the shift cylinder (1) for supplying air to the piston (4). 1c) is connected to a magnetic valve (C) for neutral position control, and the discharge port of the magnetic valve (C) is connected to another electromagnetic valve (G) via an air circuit (6). The electromagnetic valve (G) has a position for connecting the air circuit (6) to the air tank (5) and a position for releasing the air circuit (6) to the atmosphere.

[0006]

Therefore, when the magnetic valve for controlling the neutral position is normally turned on and air from the air tank is applied to the piston for controlling the neutral position, the automatic transmission becomes neutral. Therefore, there is no danger if the magnet valve fails in the ON position. However, if the magnetic valve breaks during the off state, that is, while driving, it will not be possible to stop, so
Another solenoid valve is connected to the air tank.

Then, the air in the air tank is applied from the discharge port of the magnetic valve to the piston for controlling the neutral, so that the air can be reliably made neutral. Therefore, by simply providing another solenoid valve that can switch between air release and the air tank at the discharge port of the magnetic valve of the piston that controls the neutral, the neutral can be reliably achieved, and the vehicle can be stopped with a simple configuration It is possible to reliably prevent the danger of no longer running.

[0008]

It is preferable that a double check valve is provided between the exhaust port and the another solenoid valve in each of the magnetic valve for controlling the neutral position and the magnetic valve for controlling the shift position. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a transmission 13 is mounted on an engine 11 via a mechanical clutch 12, a subtransmission 13A is mounted on the transmission 13, and an output shaft of the transmission 13 is connected to a rear axle (not shown) via a propeller shaft 14. The engine 11 is provided with a fuel injection pump 15.

A gear shift unit 16 is provided above the transmission 13, and the gear shift unit 16 is provided with a gear position switch which is a detecting means for detecting completion of gear setting.

The sub-transmission 13A is provided with a splitter actuator 18 and a range actuator 19 for operating a gear change between a splitter type and a range type.

Further, the controller 30 for controlling the transmission based on the lever position of the shift tower 24 includes a gear shift unit 16, a gear rotation sensor 20, a display monitor 22, a magnetic valve 23, and the on / off state of the shift tower 24 and the clutch 21. , And an off switch.

FIG. 2 shows the structure of the gear shift unit 16. The shift cylinder 1 is slidably provided with a shift shaft 2a having a piston 3 for operating a shifter 2, and one end of the shift cylinder controls neutral. The piston 4 is slidably fitted.

The shift cylinder 1 is provided with ports 1a and 1b for supplying air to both sides of the piston 3, respectively, and a port 1c for supplying air to one end of the piston 4. A magnetic valve A is connected to the port 1a, and a magnetic valve B is connected to the port 1b.
A magnetic valve C is connected to the port 1c. The discharge ports of the magnetic valves A and C are connected in the air circuit 6 so as to be released to the atmosphere via a solenoid valve G. When the solenoid valve G is turned on, air is discharged from the air tank 5 through the air circuit 7. Magnetic valves A and C
It is connected to supply from the exhaust port. Therefore, the position where the solenoid valve G is connected to the air tank 5 and the air circuit 6
To the atmosphere.

Further, magnetic valves D, E, and F are connected to the select cylinder 8, respectively.
The gear of the transmission 13 is operated in the select direction by a signal from 0.

Therefore, if the piston 3 stops operating due to a failure or the like while the shifter 2 is shifted to the X or Y gear position, the solenoid valve G is turned on and the air tank 5 is turned on.
Then, air can be supplied from the port 1a or 1c of the shift cylinder 1 via the air circuit 7, the solenoid valve G, the air circuit 6, and the magnetic valve A or C to return the piston 3 to the neutral position.

FIG. 3 shows another embodiment in which double check valves 9 and 10 are provided between magnetic valves A and C and a solenoid valve G which is a three-position switching valve, respectively. Is preferred.

[0019]

[Effects of the Invention] As described above, the present invention has the following excellent effects. (A) Even if a magnetic valve for a piston that controls neutral in a shifted state during traveling fails in an open-to-atmosphere state, if another solenoid valve is turned on, the piston can be reliably set to neutral. it can. (B) Therefore, there is no danger that the vehicle will not stop during traveling. (C) If another solenoid valve is connected to the air tank, the structure is simple and the conventional product can be easily improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a gear shift unit of FIG. 1;

FIG. 3 is a configuration diagram of a gear shift unit showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Shift cylinder 2 ... Shifter 3, 4 ... Piston 5 ... Air tank 6, 7 ... Air circuit 8 ... Select cylinder 11 ... Engine 12 ... Clutch 13 ... Transmission 16 ... Gear shift unit 24 ... Shift tower 30 ... Control devices A, B, C, D, E, F, G ... Magnetic valve

Claims (1)

(57) [Scope of request for utility model registration] 1. A pneumatic circuit device for an electronically controlled automatic transmission having a shift cylinder and a select cylinder, and having a magnetic valve for operating those cylinders, wherein a neutral is provided at one end of a shift cylinder (1). A piston (4) to be controlled is slidably fitted, and a port (1c) provided at one end of the shift cylinder (1) for supplying air to the piston (4) is a magnetic for neutral position control. The valve (C) is connected to a discharge port of the magnetic valve (C) via an air circuit (6) to another solenoid valve (G), and the other solenoid valve (G) is connected to the air circuit. An air circuit device for an automatic transmission, comprising: a position for connecting the air circuit (6) to the air tank (5); and a position for releasing the air circuit (6) to the atmosphere.