JPS602036Y2 - Brake valve - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a brake valve used in a vehicle.

Conventionally, when a brake valve used in a vehicle's brake system sends air pressure proportional to the operating angle of a lever to a braking device such as a spring brake, a reaction force proportional to the air pressure is applied to the lever. It was structured to add to the

Further, these brake valves may be connected to a spring brake and used as a parking brake or emergency brake device, or may be used as a brake device for a trailer vehicle.

As mentioned above, when a brake valve is used in conjunction with a spring brake, the lever that operates the brake valve has two positions: when the brake is applied for parking and when the vehicle is running. It is only necessary to provide a detent device to lock the lever.

However, when the brake valve is used as a brake device for a trailer vehicle as described above, by holding the lever that operates the brake valve in an appropriate position when the brake operation is necessary, It is required that the brakes be set at a certain appropriate level and that the driver be able to perform gear shifting operations on the transmission during that time.

In such a case, if the above-mentioned reaction force occurs on the lever that operates the brake valve, the lever cannot be held at an arbitrary position as described above.

The reason why the reaction force is generated on the lever is as follows.

In brake valves, a cam device is interposed between the lever and the pusher that operates the valve that adjusts the air pressure, and the rotation angle of the lever is controlled by the cam device to adjust the movement of the pusher in a linear direction. The air pressure is adjusted by moving the pusher in the linear direction to operate the valve.

However, during this operation, the air pressure pushes the pusher in the linear direction, and that pushing force exerts a large reaction force on the cam surface of the cam device, and that reaction force tries to move the lever. There is something that acts as a reaction force.

Therefore, when the lever is at any intermediate operating position, the driver must hold the lever by hand against the reaction force. This means that the operating method required for using the car cannot be satisfied.

An object of the present invention is to improve the above-mentioned problems and provide a brake valve that allows the lever to be held at any operating position without generating a reaction force due to operating pressure on the lever. It's about doing.

To explain the present invention based on an embodiment, FIG. 1 shows a side sectional view of a brake valve as an embodiment of the present invention, and FIG. 2 shows a view taken along the arrow in FIG. FIG. 3 shows the cam body 5 in FIG. 1 as viewed from the arrow A.

A side plate 1a is fastened to the housing 1 with a plurality of bolts, and a piston body 2 is fitted into a cylinder 1b cut into the housing 1 so that the cylinder 1b can slide in the axial direction. A chamber 2d formed by the side drawer 1a and the piston body 2 is open to the atmosphere through the connecting hole 1c, and the spring 2a provides a biasing force that biases the piston body 2 upward.

A pressure chamber 2C formed in the axial middle of the piston body 2
is connected to a constant pressure source (not shown) via a connecting hole 1d, and a pressure chamber 2e is formed in the cylinder 1f where the axially upper end surface of the piston body 2 is exposed. 2e communicates with a vehicle brake system such as a spring brake (not shown) through a connection hole 1e.

Here, each of the connection holes 1d and 1e is formed perpendicularly to the axis of the cylinder 1b from a surface 1h for mounting on the floor surface of the vehicle interior.

A port 2f is formed in the piston body 2 between the pressure chamber 2c and the pressure chamber 2e, and the valve 3 is axially inserted into the cylinder 2b of the piston body 2 cut between the chamber 2d and the pressure chamber 2c. The valve 3 is fitted with a hole 3a that communicates with the chamber 2d, and the spring 3b is seated on the valve seat 2f (a valve seat 3c formed at the shaft end of the valve 3). It gives an additional force in the direction.

A pusher 4 is fitted into the cylinder 1f cut into the housing 1 so as to be able to slide in the axial direction, and the pusher 4 has a cam surface 5a.
The pin 11 fitted into the side wall 1g of the housing 1 also prevents the cam body 5 from rotating around the axis of the cylinder 1f.
The tip of the cylinder 1f is fitted into the pusher 4 so as to be able to rotate around the axis of the cylinder 1f, and an open hole 4b is formed in the sealing surface 4c cut into the shaft end of the pusher 4. , the end surface 6a of the input material 6 is exposed to the open hole 4b, and a sealing material 6b such as an O-ring is attached to the fitting surface between the pusher 4 and the input material 6, and the end surface 6a of the input material 6 is exposed to the open hole 4b. The fitted pin 6d serves as a cam follower that rotatably contacts the cam surface 5a, and the spring 4a urges the pusher 4 upward via the piston body 2.

The input material 6 allows rotation around the axis together with the coupling 7 through the serrations 7b, and a washer 6e is fastened to the input material 6 with a bolt 6f. As a result,
The input member 6 holds the side wall 1g and the coupling 7 by the shoulder 6c and the washer 6e, and the coupling 7 fits into the peripheral surface 1m cut into the housing 1 so as to be rotatable around the axis. A sealing material 7c such as an O-ring is attached to the fitting surface.

A receiving material 7f is fitted into a cylinder 71 bored in the radial direction of the coupling 7, and a lever 7a is fitted into the receiving material 7f so that the cylinder 71 can slide in the axial direction. The receiving member 7e fitted into the cylinder 71 is fitted so as to be able to slide in the axial direction, and the spring 7g is fitted onto the receiving member 7f.
and 7e to apply an urging force to the lever 7a in the direction of 1 m of the curve.

Note that 7d is a snap ring.

Further, as shown in FIG. 2, a cap 7h made of plastic is fitted onto the tip of the lever 7a, and a peripheral surface 1 made of aluminum casting is fitted onto the tip of the lever 7a.
In m, each of the perforation j and the recess 1 is perforated.

To explain the operation of the configurations shown in FIGS. 1, 2, and 3 above, first, while pulling up the knob 7j screwed onto the lever shown in FIG. 2, operate the lever 7a to release the coupling 7. When rotated clockwise in FIG. 2, the pin 6d fixed to the input material 6 rotates around the axis of the input material 6.

As a result, the pin 6d is rotated in the direction of moving to the left in FIG.
While sliding on the top, push down the cam body 5 and the pusher 4.

Conversely, in FIG. 3, when the input member 6 rotates in the direction in which the pin 6d moves to the right, the force of the spring 4a pushes up the pusher 4 and the cam body 5, and the shaft of the pusher 4 The directional position is proportional to the operational rotation angle θ of the lever 7a.

In this embodiment, the cam surface 5a is provided on the side of the pusher 4, and the side of the input material 6 is used as a cam follower.
Since it is sufficient that the pusher 4 side is a cam follower and a cam surface is formed on the input material 6 side, the cam follower itself also has a cam surface shape. It may be a configuration.

When the lever 7a is further operated from the above state and its operation rotation angle reaches θO, the sealing surface 4c is
c, the communication between the pressure chamber 2e and the chamber 2d is closed, and as the pusher 4 is further pushed down, the pusher 4
will push down the valve 3, and the valve seat 3c will close to the port 2.
f, and compressed air from a constant pressure source flows through connection hole 1.
d.

It flows into the pressure chamber 2e through the pressure chamber 2c and the port 2f, and the operating pressure of the pressure chamber 2e increases.

As a result, this operating pressure acts on the axial end of the piston body 2, resisting the urging force of the spring 2a, and pushes the piston body 2 down, so that the port 2f comes into contact with the valve seat 3C again, and the pressure is removed from the pressure chamber 2c. Stop the inflow of compressed air.

In other words, in order for the port 2f to be pushed down again by the operating pressure of the pressure chamber 2e to the position of the valve seat 3c where the pusher 4 pushes down the valve seat 3c, the operating pressure of the pressure chamber 2e must be 2a is compressed, and the compressed position corresponds to exactly where the valve seat 3c and the port 2f come into contact.

That is, when the operating rotation angle θ of the lever 7a is set to an arbitrary constant operating rotation angle θa, the operating pressure Pa in the pressure chamber 2e is determined by the spring characteristics of the spring 2a and the axial projected area of the piston body 2. The pressure characteristic A of the working pressure P is
is as shown in FIG.

Note that in FIG. 4, a indicates the operating point at the operating rotation angle θa.

Moreover, point b in FIG. 4 indicates the operating point at the maximum operation rotation angle θb of the lever 7a.

In the above operation, when the operational rotation angle of the lever 7a corresponds to the minimum operational rotation angle θ=O, as shown in FIG. 2, the position of the cap 7h of the lever 7a corresponds to the position of the perforation 1j, and the cap When the cap 7h is in the position of the recess 1, it corresponds to the maximum operating rotation angle θb of the lever 7a. is sliding 1 m above the circumferential surface.

Next, to explain the case where this brake valve is used in combination with a spring brake, when the vehicle is running, the operating rotation angle θ of the lever 7a is set to θb, and at this time the cap 7h is set to the spring 7g. Since the lever 7a is pressed into the recess 1 by the force, even if the lever 7a is released, the operating rotation angle θb of the lever 7a remains unchanged.
does not change, and the operating pressure P at this time completely releases the spring force in the spring brake, so that the vehicle is not braked.

On the other hand, when applying the brakes to the vehicle, the lever 7a is pulled out of the recess 1k and the operating rotation angle θ
When the lever 7a is operated while the cap 7h slides on the circumferential surface of 1 m, the operating pressure P generated in the pressure chamber 2e at this time is smaller than the maximum operating pressure. Therefore, by weakening the degree of release of the spring force in the spring brake, the brakes on the vehicle will become stiffer.

Further, when the operation rotation angle θ becomes zero, the cap 7h is pressed into the borehole 1j by the biasing force of the spring 7g and is locked.

At this time, since the operating pressure P is zero, the spring force in the spring brake becomes maximum and can be used as a parking brake.

Furthermore, in the above-described operation when the sealing surface 4c is in contact with the valve seat 3c, the axial projected area of the sealing surface 4c and the axial projected area of the end surface 6a are the same value, and the pressure chamber The working pressure in the pressure chamber 2e is also led to the back surface of the pusher 4 and the cam body 5 (the upper surface portion in the axial direction of the pusher 4 and the cam body 5) through the perforation 4d. Even if this occurs, the operating pressure does not generate an axial pressing force on the pusher 4 and the cam body 5.

To explain this in more detail, as shown in FIG. 1, when the sealing surface 4c is separated from the valve seat 3c, the chamber 2d, which is at atmospheric pressure, is compressed through the perforation 3a. Since it communicates with the chamber 2e, the pressure chamber 2e also becomes atmospheric pressure.

Therefore, in this state, the cam surface 5a and the pin 6d
The cam mechanism does not generate any reaction force in the axial direction due to operating pressure.

When the sealing surface 4c is pushing down the valve 3 from the state shown in FIG. Since the gas enters the pressure chamber 2e, the pressure chamber 2e is in a pressure state.

However, in this case, the portion of the perforation 4b is replaced by the perforation 3a.
However, since the axial projected area of the seal face 4c and the axial projected area of the end face 6a are approximately the same value, the axial direction due to the operating pressure within the diameter of the seal face 4c No reaction force is generated.

Furthermore, in this case, the cam mechanism in the radially outer portion of the seal surface 4c that is equal to or larger than the outer diameter is entirely exposed in the pressure chamber 2e, so the cam mechanism in the pressure chamber 2e is The upward axial projected area and the downward axial projected area completely match.

Therefore, in the cam mechanism in this state, no reaction force in the axial direction due to the operating pressure in the pressure chamber 2e is generated.

As a result, since the cam body 5 is configured so that no axial pressing force is generated, the reaction force due to the operating pressure moves from the cam surface 5a through the pin 6d, the input member 6 and the coupling 7 to the lever 7a. This means that there is no force that would cause the input shaft 6 to rotate around its axial center.

In this case, the coupling 7 and the housing 1
A sealing material 7c that also has properties as a friction resistance material is attached to the fitting surface with the lever 7a, and the frictional resistance between the coupling 7 and the housing 1 due to the presence of this sealing material 7c is Since no reaction force is generated, the rotation angle of the lever 7a can be sufficiently maintained at a constant level at the level of the frictional resistance.

Furthermore, it will be easily understood that the frictional resistance may be provided between the input member 6 and the housing 1, which are integrally interlocked with the lever 7a.

In other words, this friction resistance material is used for the lever 7a and the housing 1.
It would be sufficient if there was an interposition between the two.

Therefore, when this brake valve is used in the brake system of a trailer vehicle and the vehicle is applying the brakes while going down a long downhill slope, when the driver feels the need to apply engine braking. In this case, the driver releases the lever 7a while holding the lever 7a in a position where the necessary brake is applied between the perforation 1j and the recess 1, and then, while holding the lever 7a in that position, the driver stops driving. The operator can set the engine braking state to the engine by operating the transmission.

In this case, if the lever is configured to generate a reaction force as in the past, the above operation cannot be performed.

The reason is that as soon as the driver releases his hand from the lever in such a state, the reaction force moves the lever to θ=
This is because the brake is returned to the 01 position, making it impossible to maintain an appropriate braking state for the trailer vehicle.

As is clear from the above description, the brake valve according to the present invention has the following effects.

In addition to the fact that the lever 7a is not subjected to any reaction force due to its operating pressure, the invention of the present invention also includes a friction resistance material interposed between the lever 7a and the housing 1, and the lever 7a, the spring 7g, ? Since it has a detent device consisting of a hole 1j and a recess 1k, 1. When the parking brake is applied, the detent device is fixed in one position to fix the vehicle in the braking state, and when the vehicle is running, the detent device is not used. By fixing it to the other position, it is possible to keep the brake in the released state, and 2. When the brake valve of the present invention is used in the brake system of a trailer vehicle, the lever 7a can be moved to any operating position. Therefore, when the brake is required, the driver can maintain the operating position of the lever 7a at a position between the perforation 1j and the recess 1 to achieve the necessary braking state as necessary. During this time, the user can release the lever 7a and shift the transmission to the engine braking position or the like.

[Brief explanation of the drawing]

FIG. 1 shows a side cross-sectional view of a brake valve as an embodiment of the present invention, FIG. 2 shows a view taken along the arrow in FIG. This is a diagram showing the cam body 5 viewed from the side in FIG. 1, and FIG. 4 is a diagram showing the operating pressure characteristic A in the pressure chamber 2e. The symbols used in the examples are as follows. 1...Housing, 1a...Side plate, 1
b and 1f...Cylinder, 1c, 1d and 1e...Curved connection hole, 1g...Side wall, 1h...
...Mounting is by surface, 11...pin, 1j...
...Drilling (locking hole), 1k...Bobomi (locking hole)
, 1m...peripheral surface. 2...Zeston body, 2a...Spring, 2b...Curved cylinder, 2C and 2e...Pressure chamber, 2d...Chamber, 2f... ··port. 3... Valve, 3a... Perforation, 3b...
...Spring, 3c... Valve seat. 4...Press, 4a...Spring, 4
b...Open hole, 4c...Seal surface, 4
d...Perforation. 5...Cam body, 5a...Cam surface. 6.
...Input material, 6a...End face, 6b...
...Seal body, 6c...Shoulder, 6d...
Pin, 6e...washer, 6f...bolt. 7... Coupling, 7a... Lever, 7b... Serration, 7c... Seal material, 7d... Snap ring, 7e and 7f...Received material, 7g...Spring,
7h・song・cap, 71... cylinder, 7j
・Song/Knob. P... Working pressure in curved pressure chamber 2e, θ...
Operation rotation angle of lever 7a.

Claims (1)

[Claims for Utility Model Registration] A piston body 2 is fitted into a cylinder 1b bored in the housing 1 so as to allow sliding movement in the axial direction in the cylinder, and one shaft end of the piston body and the A spring 2a is interposed between one shaft end of the cylinder, a chamber 2b enclosing the spring communicates with the atmosphere, and a pressure chamber 2 is located in the middle of the piston body in the axial direction.
c, and the pressure chamber has a connection hole 1d bored in the wall of the cylinder.
, and on the side of the piston body opposite to the chamber in the axial direction, there is another pressure chamber 2e.
The other pressure chamber always communicates with the brake device via another hole 1e bored in the wall surface of the cylinder, and in the piston body, the other pressure chamber and the pressure are connected in the axial direction. A port 2f that selectively communicates between the chambers is provided, and the port is provided with a valve 3 that selectively closes the port from the pressure chamber side to the other pressure chamber side, and the valve is connected to the A piston-shaped shaft is formed on the side of the chamber in the axial direction, and the other cylinder 2b, which penetrates from the pressure chamber to the chamber in the piston body and is bored in the axial direction, has a piston-like shaft formed on the side of the chamber in the axial direction. The outer diameter portion of the shaft is fitted to enable sliding, and the shaft is provided with a hole 3a for selectively communicating the chamber and the other pressure chamber in the axial direction. , applying a biasing force to the valve from the chamber side toward the port side in the axial direction by a spring 3b; In the side wall 1g portion of the input material, one shaft end is exposed to the other pressure chamber and the other shaft end is exposed to the atmosphere,
The shaft end of the input member that is rotatably fitted and exposed to the other pressure chamber has a round shaft shape in the axial direction, and the tip thereof is connected to the other pressure chamber. The pusher 4 is slidably fitted into the perforated portion of the pusher 4 exposed to the hole, the tip of the pusher on the side of the chamber forms a sealing surface 4c, and the chamber in the perforated portion of the pusher A perforation 4b having a diameter smaller than the perforation diameter of the perforation part is penetrated from the bottom part of the perforation part to the sealing surface, and the outer diameter of the sealing surface is sufficiently medium than the inner diameter of the port. A cam mechanism is disposed so as to be enclosed in the port in the radial direction, and is exposed in the other pressure chamber between the input material and the pusher in the axial direction, and the cam The mechanism is configured such that rotation of the input material around an axis causes movement of the pusher in the axial direction, and the sealing surface is configured such that: a: the pusher moves toward the chamber in the axial direction; when the - hole in the valve is closed and the valve is pressed toward the chamber side to communicate the pressure chamber and the other pressure chamber, b= the pusher is in the axial direction when moving towards the side wall, the - hole is left in the closed state, and the valve thereby closes the communication between the pressure chamber and the other pressure chamber, a and b above. The axial projected area of the sealing surface has a value approximately equal to the axial projected area of the tip of the input material fitted to the pusher, and the blade material has the following configuration: The exposed part is lever 7a
A brake valve having the above structure, wherein a friction resistance material and a detent device are interposed between the lever and the housing.