JPH0318725Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an air leak alarm device for an air cylinder device used for shifting the transmission of a vehicle, etc. , an air flow rate sensor is installed, and an alarm device connected to the flow rate sensor is installed in the driver's seat, for example, so that air leakage from the transmission air cylinder can be detected from the driver's seat even in rear-engine buses. Relating to a leak alarm device.

Prior Art In FIG. 2, a conventional air cylinder device 1
has a pair of first and second outer pistons 3, 4 within the cylinder 2 and slidable relative to the cylinder.
, an inner piston 5 that is slidable relative to the outer piston, and a piston rod 6 that is fixed to the inner piston. A second airport P ₁ and a second airport P ₂ are provided. A ring-shaped stopper 8 is fixed to the axial center of the inner circumferential surface 2c of the cylinder 2, and a first
The rightward movement of the outer piston 3 or the leftward movement of the outer piston 4 is restricted by the stopper. Breathing holes 9 were provided on both sides of the stopper 8 and communicated with the outside of the cylinder 2. Also, the outer pistons 3 and 4
A sealing member 10 for maintaining airtightness was installed between the inner circumferential surface 2c of the cylinder 2 and the inner circumferential surfaces 3c, 4c of the inner piston 5 and the outer pistons 3, 4.

In the air cylinder device 1, a second air port is connected to the first air port _P1 as shown by arrows A and B.
When air is sucked and discharged into _P1 as shown by arrows C and D,
The outer pistons 3, 4 can each move to the leftmost position or the rightmost position or the neutral position shown, and the inner piston 5 accordingly moves to three points and stops at the respective positions. In this case, when the outer pistons 3, 4 move from side to side, a vacuum or high pressure condition naturally occurs within the cylinder 2. Air passes through this breather hole 9 as indicated by the arrow E.
Breathing is done by flowing in or out like F. When the air cylinder device 1 is used for a long period of time, the sealing member 10 will eventually wear out and the high pressure air supplied from the air ports P ₁ and P ₂ will leak between the inner circumferential surface 2c of the cylinder 2 and the outer pistons 3 and 4. It begins to leak from between the inner circumferential surfaces 3c, 4c of the outer pistons 3, 4 and the inner piston 5.

Problem to be solved by the invention However, in the conventional example, the breathing hole 9
Since no special measures had been taken for the system, it was impossible to distinguish between cases where only breathing air was flowing and cases where high-pressure air leaked. However, there was a drawback in that transmission malfunctions could not be predicted.

The present invention was made in order to eliminate the above-mentioned drawbacks of the prior art, and its purpose is to attach an air flow rate sensor to a breathing hole provided in a cylinder, and to attach an alarm to the flow rate sensor. By connecting a To enable air leakage of a transmission shift air cylinder to be detected from a driver's seat even when the transmission is located at the rear of a vehicle as in an engine bus, and to easily predict a shift operation failure.

Means for Solving the Problems In short, the present invention includes a pair of outer pistons that are slidable relative to the cylinder, and an inner piston that is slidable relative to the outer pistons, which are housed in a cylinder. In an air cylinder device in which a breather hole for the outer piston is provided in the axial center of the cylinder so as to communicate with the outside of the cylinder, an air flow rate sensor is attached to the breather hole, and the flow rate sensor This device is characterized by being equipped with an alarm that issues an alarm when the air flow rate is detected.

Effect The seal member may wear out due to long-term use,
If the cylinder is damaged, the high-pressure air supplied from the air port and present in the cylinder will leak from between the outer piston and the inner peripheral surface of the cylinder and flow into the breather hole in large quantities and at high speed. The flow rate sensor detects a large amount of air and sends current from the power source to the alarm, causing an alarm. Therefore, the driver can immediately sense that the air cylinder device for shifting or selecting the transmission has failed.

Embodiments The present invention will be explained below based on embodiments shown in the drawings. In FIG. 1, an air cylinder device 11 according to the present invention includes a pair of outer pistons 3 and 4 that are slidable with respect to the cylinder 2, and an inner piston that is slidable with respect to the outer piston. 5 is housed therein, and a breather hole 9 for the outer pistons 3 and 4 is provided in the axial center of the cylinder so as to communicate with the outside of the cylinder 2.

The air leak alarm device 12 of the air cylinder device according to the present invention has an air flow rate sensor 1 installed in the breather hole 9.
3, and an alarm device 14 that issues an alarm when the flow rate sensor detects a flow rate of air exceeding a certain amount.
is connected to the flow rate sensor 13 through a conductor 15, and a power source 16 is connected through a conductor 18, and the alarm 14 is attached to, for example, the driver's seat of a vehicle. As the alarm 14, for example, a buzzer,
A red lamp or the like may be considered, or other lamps may be used.

The rest of the structure is the same as that of the conventional example shown in FIG. 2, so the same parts are given the same reference numerals in the drawings and their explanation will be omitted.

The present invention is constructed as described above, and its operation will be explained below. In the cylinder 2, a pair of outer pistons 3, 4 and an inner piston 5 move to provide a breathing effect through the breathing hole 9.
This is done by sucking and discharging air through the flow rate sensor 13 as shown by arrows E and F, but since the flow rate of air in this case is small, no current flows to the alarm device 14 and no alarm is issued.

However, if the seal member 10 becomes worn or damaged due to long-term use, the air port
The high pressure air supplied from P ₁ or P ₂ and present in the cylinder 2 is connected to the outer pistons 3 and 4 and the cylinder 2.
A large amount of air leaks from between the inner circumferential surface 2c and flows into the breathing hole 9 at a high speed, and as a result, the flow rate sensor 13 detects a large amount of air and the power source 16
An alarm is issued because the current from the terminal is passed through the alarm device 14. Therefore, the driver can immediately notice that the air cylinder device 11 for shifting or selecting the transmission has failed.

Effects of the invention The present invention is constructed and operates as described above, so an air flow rate sensor is attached to the breather hole provided in the cylinder, and an alarm is connected to the flow rate sensor. The alarm can be configured to issue an alarm if the sealing member of the vehicle is worn and high-pressure air leaks into the breather hole, and the transmission is located at the rear of the vehicle, such as in a rear-engine bus. However, it is possible to detect air leakage from the transmission air cylinder from the driver's seat, and it is possible to easily predict a shift operation failure.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an air cylinder device equipped with an air leak alarm device according to the present invention, and FIG. 2 is a longitudinal sectional view of a conventional air cylinder device. 2 is a cylinder, 3 and 4 are outer pistons, 5 is an inner piston, 9 is a breather hole, 11 is an air cylinder device, 12 is an air leak alarm device for the air cylinder,
13 is an air flow rate sensor, and 14 is an alarm.

Claims (1)

[Scope of utility model registration request] A pair of outer pistons that are slidable with respect to the cylinder and an inner piston that are slidable with respect to the outer piston are housed in the cylinder, and a breather for the outer piston is provided in the axial center of the cylinder. In an air cylinder device in which a hole is provided in communication with the outside of the cylinder, an air flow rate sensor is attached to the breather hole, and an alarm is issued when the flow rate sensor detects a flow rate of air exceeding a certain amount. An air leak alarm device for an air cylinder, characterized by being equipped with an air cylinder.