JPH027246Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an actuator for an exhaust brake of a large vehicle, and more particularly to an actuator that can prevent damage to a diaphragm within the actuator.

An exhaust brake is a brake that stops the discharge of engine exhaust gas and controls engine operation by blocking a butterfly valve provided in the exhaust path of the engine.The butterfly valve is operated by, for example, an actuator. ing.

FIG. 1 shows a sectional view of a conventional exhaust brake actuator.

In the conventional actuator 1a, vacuum pressure from a vacuum tank (not shown) is applied to the actuator body 3 through a conduit 2, and vacuum pressure from the actuator body is applied to the actuator body 3 through the conduit 2. 4 to spring 5
The actuating shaft 6 of a butterfly valve (not shown) provided in the exhaust pipe is actuated by responding in the direction of the arrow. Then, the actuator body 3 is removed from the gap between the actuator body 3 and the operating shaft 6.
A drain hole 7 for discharging muddy water or the like that enters the actuator body 3 is formed on the actuation shaft 6 side of the actuator body 3.

Conventional actuator 1a with such a configuration
When muddy water or the like enters the actuator main body 3 through the water drain hole 7 and the sliding part of the operating shaft 6, the muddy water that has not been discharged from the water drain hole 7 comes into contact with the diaphragm 4, and the diaphragm 4
There was a risk that the damaged actuator 1a would malfunction.

The present invention was developed in view of the above points, and its purpose is to completely prevent damage to the diaphragm inside the actuator due to muddy water. In an exhaust brake actuator that has a water drain hole formed in the body of the exhaust brake actuator that drives a butterfly valve actuating shaft in response to pressure, a vacuum valve that has a drainage channel that contracts and closes in diameter due to negative pressure is used. The point is that it is attached to the water drain hole portion of the actuator main body.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a sectional view of the exhaust brake actuator according to the present invention.

As is clear from Fig. 2, actuator 1
The actuator body 3 is provided with a conduit 2 connected to a vacuum tank (not shown) at the top for applying vacuum pressure to the actuator body 3, and an actuating shaft 6 that slides in response to this vacuum pressure is attached to the actuator body 3. It penetrates through the actuator body 3 and is fixed to the diaphragm 4 mounted inside the actuator main body 3 by a center plate 4a. The valve is operated in response to the vacuum pressure of the diaphragm 4 to open and close a butterfly valve (not shown) provided in the exhaust pipe.

On the operating shaft 6 side of the actuator main body 3,
A drain hole 7 is formed to drain muddy water that has entered the actuator main body 3. A spring 5 biases the diaphragm 4 and is installed between a cylindrical spring receiver 8 attached to one side of the diaphragm 4 and a spring receiver 9 attached to the inner surface of the actuator main body 3 facing the spring receiver 8. has been done.

In the present invention, the drainage channel 10a is reduced in diameter and closed when negative pressure is applied to the drain hole 7.
A vacuator valve 10 having a distal end thereof is attached. The vacuum evacuator valve 10 is made of an elastic material such as rubber, and, as described above, is a valve that closes when negative pressure is applied to the drainage channel 10a.

Furthermore, in this embodiment, a baffle plate 11 is provided between the water drain hole 7 and the diaphragm 4 to prevent muddy water or the like that has entered through the operating shaft 6 portion from coming into contact with the diaphragm 4. . The diaphragm 4 has a communication portion 11a that communicates with the back space 13 at the center of the buff full plate 11.
is formed, so that when the diaphragm 4 responds to negative pressure, the space 14 formed by the baffle plate 11 as well as the back space 13 becomes negative pressure.

Next, the operation of the present invention will be explained.

The actuator 1 causes a diaphragm 4 attached to the actuator body 3 to respond in the direction of the arrow against a spring 5 by applying vacuum pressure from a vacuum tank to the actuator body 3 through a conduit 2, thereby causing the exhaust pipe to move. It drives the operating shaft 6 of the provided butterfly valve.

When the actuator 1 is operated, the spaces 13 and 14 of the actuator body 3 become negative pressure, but at this time,
Drain channel 10 at the tip of the vacuum evacuator valve 10
The diameter of a is reduced by this negative pressure. Therefore, the actuator valve 10 is closed, and muddy water or the like can be prevented from entering the actuator main body 3 through the water drain hole 7.

On the other hand, when the actuator 1 is not operating, the spaces 13 and 14 do not have negative pressure, so the drainage channel 10a of the vacuum actuator valve 10 is in an open state, and muddy water etc. that have entered the actuator body 3 are removed. Discharge effectively.

Furthermore, even if some muddy water etc. enters into the actuator main body 3 through the gap between the actuating shaft 7 and the actuator main body 3, the muddy water etc. can be prevented from entering the diaphragm by installing the buttful plate 11 with the communication hole 11a. It can prevent up to 4 intrusion,
This makes it possible to further prevent diaphragm damage.

As is clear from the above explanation, according to the present invention, a vacuum valve having a conduit portion that contracts in diameter and closes due to negative pressure is attached to the water drain hole portion of the actuator body, so that the water drain hole It is possible to prevent muddy water etc. from entering the actuator main body through the actuator body, thereby preventing damage to the diaphragm in the actuator main body due to muddy water etc. and preventing malfunction of the actuator.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional example, and FIG. 2 is a sectional view of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Actuator, 3... Actuator main body, 4... Diaphragm, 6... Butterfly valve operation shaft, 7... Drain hole, 10... Vacuum evacuator valve, 10a... Drain channel, 11... Batsuful plate.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) An exhaust brake formed by forming a water drain hole in the body of an exhaust brake actuator in which a diaphragm installed in the actuator body drives a butterfly valve operating shaft in response to negative pressure. 1. An actuator for an exhaust brake, characterized in that a vacuum valve having a discharge passage whose diameter is contracted and closed by negative pressure is attached to a water drain hole portion of the actuator body. (2) The actuator for an exhaust brake according to claim 1, which is a registered utility model, characterized in that a buttful plate having a communication hole is provided between the diaphragm and the water drain hole in the actuator main body.