JPS6099760A - Vacuum brake power booster - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vacuum brake power booster, and more particularly, to a vacuum brake power booster that includes a partition wall movable in the axial direction within a vacuum housing, a piston rod connected to a brake pedal, and a piston rod connected to a brake pedal. a control valve actuated by the control valve, and a pressure chamber capable of communicating with the vacuum chamber; A second valve device is formed by the valves 1 to 1 and a valve piston connected to the piston rod, and the partition wall has a kite extending perpendicularly to the axial direction. A control valve box provided with a control valve box and a horizontal member passing through this guide are connected, and when the brake is not activated, the outer end of the horizontal member protruding from the control valve box contacts the vacuum housing. Regarding boosters.

[Prior Art] The vacuum brake power booster described above has an axially movable partition within the vacuum housing, which partition divides the space within the vacuum housing into a vacuum chamber and a pressure chamber.

Since a pressure difference is generated in these chambers through the partition wall, the partition wall moves in the direction of the vacuum chamber due to this pressure difference. Furthermore, this type of vacuum brake power booster has a control valve actuated by the brake pedal, which control valve controls the atmosphere acting on the bulkhead. This bulkhead is usually connected to the brake mask cylinder of a motor vehicle brake system, so that when the bulkhead moves in the direction of braking due to a pressure difference, pressure medium flows out of the brake mask cylinder, resulting in a brake pressure.

In an automobile brake system, the brake pedal is actuated during the adjustment of the brake pressure, and the communication between the vacuum chamber and the pressure chamber is reduced by 4% by the control valve. It is important in vacuum brake power boosters to be reduced to a minimum limit.

The vacuum brake power booster described above is described in German Published Patent Application No. 3042096 A1. This vacuum brake power booster has a wedge provided with play between the valve piston and the control valve box, and when the brake is not activated, this wedge abuts against the vacuum housing and the valve seat is pressed against the poppet. Slightly away from the valve. This vacuum brake power booster has a problem in that it cannot eliminate friction.

[Problems that the defense seeks to solve] The present invention provides a vacuum brake power booster that eliminates movement from brake application and allows fluid pressure to act directly on the bulkhead when the driver depresses the brake pedal. That's true.

[Means for Solving the Problems] The valves 1 to 1 are provided with an end face that acts as a valve plate at the end on the valve piston side, and a liner, and this liner covers a portion that protrudes from the end face in the axial direction. and at least one opening into which the radially extending transverse member engages, the opening comprising a recess.

According to an embodiment of the invention, said liner is bush-shaped and has an opening in which mutually parallel arms forming part of the branching portion of the cross member engage, Preferably, the free end of the outwardly projecting cross member extends through a guide provided in the control valve housing and abuts a sealing ring of the vacuum housing when the brake is not activated.

Furthermore, the opening in the liner is sized to allow the transverse member to pass therethrough with play, so that the radial outflow and inflow of atmospheric air is unobstructed, and the end of the liner on the brake pedal side Preferably, the portion is provided with a radially extending flange portion which is at least partially embedded in the poppet valve and which stiffens the shoulder of said poppet valve.

According to an embodiment of the invention, the width of the guide is such that when the brake is not activated, that is, when the cross member is in contact with the sealing ring, there is play between the cross member and the control valve body. However, it has been decided.

The radially inner end of the transverse member has a branched shape, and the two arms extending in the radial direction at the inner end surround the neck of the control valve with play, and the center of the arm engages the liner.

The opening is an annular groove or notch provided at the end of the liner on the valve piston side.

In an embodiment of the invention, the end of the poppet valve on the piston rond side is connected to the control valve box, and a bellows portion of the poppet valve is connected between the shoulder of the valve and the end on the piston rond side. It is provided. In addition, the ends of the poppet valves 1 to 1 on the valve piston side are pressed by a spring in the direction of the valve piston, one end of this spring is supported by the shoulder of the piston rod, and the other end is inside the shoulder of the poppet valve. It is supported by the stepped part.

[Example] Hereinafter, one embodiment of the present invention will be explained based on the drawings.

As shown in FIG. 1, the vacuum brake power booster has a vacuum housing 1.
is divided into a pressure chamber 3 and a vacuum chamber 4 by an axially movable partition wall 2. The bulkhead 2 seals between a dish-shaped diaphragm disk 5 made of a deep-drawn metal plate, a flexible diaphragm 6 attached to the diaphragm disk 5, and the periphery of the vacuum housing 1 and the diaphragm disk 5. It has a rolling diaphragm 7.

The control valve 9 operated by the piston rod 8 is provided with a valve piston 10 which is connected to the piston rod 8 and controls opening and opening of the control valve box 11. 1st
As shown in the figure, when the brake does not operate, the control valve box 1
Since the passage from the air guide tough 1-12 provided in the air guide tube 1 to the circumferential surface of the control valve box 11 is blocked, communication between the pressure chamber 3 and the vacuum chamber 4 is blocked. When the brake is activated, ie when the piston rod 8 moves in the direction of the arrow in FIG. 2, the communication between the vacuum chamber 4 and the pressure chamber 3 remains blocked. but,
As atmospheric air flows into the pressure chamber 3, the partition wall 2 moves toward the vacuum chamber 4.

A rubber reaction disk 13 housed in the four parts of the control valve box 11 applies braking force to a mask cylinder provided on the vacuum chamber 4 side of the brake power booster via a bushing rod 14 provided with a head flange 15. to the actuating piston (not shown). A compression spring 16 supported at both ends by the inner wall 24 of the vacuum housing 1 and the diaphragm disk 5 biases the partition wall 2 in a direction in which the brake does not operate.

The diaphragm disc 5 has a cup-shaped hub portion 17
The radially inwardly projecting flange 18 of this hub portion 17 abuts against a shoulder 19 of the control valve body 11 .

A3 inside the control valve box 11, when the brake is in the maximum state of operation, that is, when the piston rod 8 moves in the direction of the arrow, the poppet valve 21 and the valve seat 20 of the valve piston 10
Since the air is separated from the air, air flows into the filter-like chamber 25. Further, the annular chamber 25 communicates with the pressure chamber 3 via a guide 26 extending in the radial direction of the control valve box 11 and a duct 38 consisting of a groove, so that atmospheric air flows into the pressure chamber 3 and As a result, the partition wall 2 moves toward the inner wall 24 against the compression spring 16. Since the bulkhead 2 is connected to the control valve box 11, the bushing rod 14 moves to the left and the mask cylinder (not shown)
is given power. This mask cylinder is fixed to the flange 28 of the vacuum housing 1 with a J bolt 27.

When the piston rod 8 is returned to the opposite direction of the arrow A by the tension spring 45, that is, to the initial state, the valve seat 20 of the valve screw 10 comes into contact with the poppet valve 21.
Communication from chamber 22 to annular chamber 25, ie pressure chamber 3, is cut off. When the brake operation is returned to the initial state, the shoulder 29 of the valve 21 is separated from the valve seat 30 of the control valve box 11, so the control valve box 11 moves to the right, and as a result, the valve 26 moves to the right. , the pressure chamber 3 and the annular chamber 3 via the duct 38 and the annular chamber 25.
1 communicates with each other, and the annular chamber 31 and the vacuum chamber 4 communicate with each other via the air guide duct 12.

When the pressure in the pressure chamber 3 and the vacuum chamber 4 become equal, the partition wall 2 moves to the right side together with the control valve box 11,
The transverse member 32 rests on a sealing ring 33 fixed to the vacuum housing 1, and the valve seat 30 rests on the shoulders 29 of the valves 1-21.

By means of the arms 35, 36 of the transverse member 32, the transverse member 32 partially surrounds the necks 34 of the valves 1-21, and by means of the implantable ports 1-37, the transverse member 32 partially surrounds the necks 34 of the control valve housings 11.
radial movement is prevented. In the axial direction of the control valve box 11, in the direction of the arrow A or in the opposite direction of the arrow A,
The horizontal member 32 has a width f of the guide 26 and a thickness f of the horizontal member 32.
One movement is possible for a distance determined by . The slidable range of the transverse member 32 defines the distance between the valve seat 20 and the poppet valve 21 moving over the valve seat 30, since the transverse member 32 engages the opening 5o of the liner 39 and This is because the movement of the shoulder portion of the poppet valve 21 is adjusted by the width q of the opening 5o.

In order to eliminate or precisely define piston rod 8 movement, a liner 39 is provided in shoulder 29 of valve 21. As a result, as shown in FIG. 2, when the brake is not activated, the shoulder 29 of the poppet valve 21
The end face 40 on the mask cylinder side does not move to the left of the position shown in FIG. 2 with respect to the control valve box 111.

A compression spring 41 is provided so that when the brake is activated, that is, when the piston rod 8 moves in the direction of the arrow, the shoulders 29 of the valves 1 to 21 come into contact with the valve seats 30. One end of the compression spring 41 is supported by the shoulder 42 of the piston rod, and the other end is supported by the flange 4.
3, the poppet valve 21 is pushed in the direction of the arrow. When the piston rod 8 moves in the direction of arrow A, the valve disc 20 of the valve screw 1 hem 10 also moves toward the end surface 40.
At this time, the shoulder 29 of the poppet valve 21 does not move. This is because the liner 39 supported by the valve seat 30
This is because the end face 40 is maintained in a state where no brake is applied to the control valve box 11.

When returning from a state in which the brake is applied to a state in which the brake is not applied, that is, when the control valve box 11 moves in the opposite direction of arrow A, the tension spring 45 pulls the poppet through the piston rod 8 and the valve piston 10. 1 to valve 21
Since the shoulder 29 of the poppet valve 21 is pressed to the right side, the shoulder 29 of the poppet valve 21 is separated from the valve seat 30. While the control valve box 11 is moving in the opposite direction of the arrow A, the transverse member 32 abuts the fixed sealing ring 33, i.e. connected to the vacuum housing 1 and the C1 valve plate 30 is closed to the valve poppet 1. 21 shoulder part 2
Contact with 9.

The operation of the vacuum brake power booster will be explained below.

When the brake is not activated, the transverse member 32 rests against the sealing ring 33. Further, the shoulder portion 21 of the poppet valve 21 is in contact with the valve seat 30, and the end face 40 is in contact with the valve seat 20. Furthermore, a cross member 32 is maintained with play within the guide 26 and rests against the liner 39, pressing it in the direction of arrow A.

At maximum brake operation, the transverse member 32 separates from the sealing ring 33 and the compression spring 41 presses the poppet valve 21 against the valve seat 30. Further, since the piston rod 8 is moving in the direction of arrow A, the valve piston 10 is separated from the end face 40. Furthermore, the control valve box 11 is moving in the direction of arrow A.

When the brake is partially applied, this situation is substantially the same as when the brake is at its maximum, but the valve seat 20 of the valve piston 10 rests against the end face 40.

When returning from a state in which the brake is applied to a state in which the brake is not applied, the piston rod 8 moves in the opposite direction of arrow A, and the shoulder 20 of the valve 21 resists the compression spring 41. and move away from the valve seat 30. , the transverse member 32 does not yet come into contact with the sealing I-nong 33, but moves within the guide 26 in the direction opposite to the arrow EflA.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the present invention, and Fig. 2 is an enlarged view of the vacuum brake power booster shown in Fig. 1. Fig. 3 is an enlarged view of the vacuum brake power booster shown in Fig. 1. It is a front view of the horizontal member shown. 1... Vacuum housing 9, 2. - Partition, 3... Pressure)
j chamber, 4... Vacuum chamber I7, 8... Piston rod 1-'', 9... Control valve, 10... Valve piston, 11... 1lill Ill valve box, 21...
Frontage 1~Valve, 26...Power 1mm, 32...Horizontal member, 39...Passir, 50...Width 8BO Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Scope of Claims] (1) A partition wall movable in the axial direction within a vacuum housing, a piston rod connected to a brake pedal, a control valve operated by the piston rod, and a control valve connected to a vacuum chamber via the control valve. the first valve device is formed by a valve seat of the control valve box and a poppet valve biased toward the valve seat, and the second valve device is formed by a poppet valve that is biased toward the valve seat. and a valve piston connected to a piston rod, the control valve box being provided with a kite extending perpendicularly to the axial direction and connected to the control valve box and a transverse member passing through the guide, When the brake is not activated, the outer end of the transverse member protruding from the control valve box, or
In the vacuum brake power booster that comes into contact with the vacuum housing, the poppet valve is provided with an end face that acts as a valve plate at the end on the valve piston side, and a liner, and the liner has a portion that projects in the axial direction from the end face. and a radially extending transverse member engages at least 111! A vacuum brake power booster having an opening of a. (2) The liner is bush-shaped and has an opening in which mutually parallel arm portions forming part of the branching portion of the cross member engage, and the cross member projects outward in the radial direction of the liner. The free end of the control valve extends through a kite provided in the control valve box and abuts a sealing ring of the vacuum housing when the brake is not activated. Vacuum brake power booster. <3) The opening of the liner has a size such that the horizontal member passes through it with play, and the opening does not prevent air from flowing out and flowing in the radial direction. A vacuum brake power booster according to item 1 or 2. 4) The end of the liner on the brake pedal side is provided with a flange portion extending in the radial direction, and this flange portion is at least partially embedded in the valves 1 to 1, and the flange portions are at least partially embedded in the valves 1 to 1. The vacuum brake power booster according to any one of claims 1 to 3, characterized in that the shoulder portion is made rigid. (5) The width of the kite is determined so that when the brake is not activated, that is, when the lateral member is in contact with the sealing ring, there is play between the lateral member and the control valve box. The vacuum brake power booster according to claim 2, characterized in that: (6) The inner end in the radial direction of the horizontal member has a branched shape,
Claims: Two radially extending arms at the inner end surround the neck of the control valve with play, and the centers of the arms engage the liner. The vacuum brake power booster according to any one of Items 1 to 5. (7) The opening is an annular groove or a notch provided at the end of the liner on the valve piston side. Vacuum brake power booster. (8) The end of the poppet valve on the piston rod side is connected to the control valve box, and a bellows part of the poppet valve is provided between the shoulder of the poppet valve and the end on the piston rod side. A vacuum brake power booster according to any one of claims 1 to 7. (9) The end of the poppet valve on the valve piston side is pressed by a spring in the direction of the valve piston, one end of this spring is supported by the shoulder of the piston rond, and the other end is inside the shoulder of the poppet valve. The vacuum brake power booster according to any one of claims 1 to 8, characterized in that the vacuum brake power booster is supported by a stepped portion of the vacuum brake power booster.