JPS58141956A - Regulator for braking force of hydraulic brake gear for automobile - 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 The present invention provides a braking force adjustment device for a hydraulic braking device of Ikl/JK, which includes a main body, in which first and second inlet chambers and first and first inlet chambers are provided. two outlet chambers are provided for the first and second braking circuits, both outlet chambers being separated from each other by a balance piston;
A stepped piston is provided between the first inlet chamber and the outlet chamber, the larger front face of the stepped piston defining the first outlet chamber to reduce the volume of the first outlet chamber. the first direction by the spring
an outlet chamber is energized, and a valve is mounted between the first inlet chamber and the outlet chamber, the valve being controlled in response to pressure by the position of the stepped piston with respect to the counterbalancing piston; and an outlet chamber, in which a further control pulp is provided.

Braking force regulators of this type are installed in particular for diagonally divided motor vehicle brake systems, in which the front wheels and the front wheels are arranged diagonally opposite the front wheels. The rear wheels are connected to two braking circuits.

The purpose of the braking force adjustment device used in such automobile braking systems is that when the pressure applied to the rear wheel brakes reaches a certain value and the car enters a certain deceleration state, the brake force adjustment device used in the braking system of a car The purpose is to reduce the pressure increase that occurs in the wheel brakes.

In the known braking force adjustment device of the above-mentioned type (see German Patent Publication No. 2.820.768), a stepped piston is mounted axially alongside a balance piston. Both pistons are made hollow and are each equipped with a valve body and a spring, which biases the corresponding valve body in the direction of the valve seat provided on the corresponding piston. Both valve bodies each have an axially outwardly projecting extension. In a stationary state, the extending portion of the valve body provided on the stepped piston is in contact with the balance piston, and the extending portion of the valve body provided in the balance piston is in contact with the main body. Therefore, in the resting state both valves are held open, so that the first inlet chamber is connected with the first outlet chamber via a stepped piston and the second inlet chamber is connected via a counterbalancing piston. Connected with a second outlet chamber. The second inlet chamber surrounds a valve mounted in the balance piston and is additionally connected to the second outlet chamber through a passage containing a valve that is controlled in response to deceleration conditions. There is. The valve, which is adapted to operate in response to deceleration conditions, is formed of a ball-shaped valve body that moves within a hole in the main body that extends axially toward both pistons, and a plug that closes the hole. It consists of a valve seat and a valve seat.

In the above-mentioned known braking force adjustment device, during a braking operation, if the pressure in the first outlet chamber exceeds a certain level, the stepped piston resists the force of the spring biasing the stepped piston. The balance piston tends to move away from the balance piston in the opposite direction and expand the volume of the first outlet chamber. The balance piston follows the stepped piston, thereby maintaining pressure equilibrium between the two river rotary bars. When the balance piston moves, the valve installed in the balance piston closes, so that the second outlet chamber can only be opened under the precondition that the pulp operating according to the deceleration condition is still open. You can't increase the pressure inside. As the stepped piston moves further, the pulp contained in the stepped piston also closes, and then the pressure in both outlet chambers is lower than the pressure in both inlet chambers. It just boosts the pressure. Note that this ratio is determined by the ratio of the areas of the front and rear surfaces of the stepped piston.

If the first braking circuit of a motor vehicle brake system, which is connected to a known braking force adjustment device, fails, the counterbalanced piston will resist the spring biasing the stepped piston without the aid of the stepped piston. It works. Therefore, the pressure in the second outlet chamber is limited only by the pressure that must take into account the arrest of the rear wheel connected to the second braking circuit. Conversely, if the 20th brake circuit fails, the pulp contained within the stepped piston will close prematurely. This is because in this case the balance piston no longer follows the stepped piston. This causes the pressure in the first outlet chamber to decrease earlier than the pressure in the first inlet chamber, which is not desirable. This is because the braking of the rear wheels connected to the still active WJ10 brake channel will be weaker than when both brake circuits are in a normal state.

SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a brake adjustment device of the type mentioned at the outset, in the event of a failure of one brake circuit, reducing the influence on the pressure change in the outlet chamber of the other brake circuit, and also reducing the braking force. The aim is to construct the entire adjustment device in a simple and space-saving manner.

The above object is achieved according to the invention by mounting the stepped piston in a balancing piston together with a spring biasing the stepped piston and a pulp adapted to operate in response to pressure, This was achieved by arranging the control of the pulp independent of the position of the piston (by means of a stepped piston, which was adapted to act in response to pressure).

The braking force adjusting device according to the present invention is only equipped with one pulp that is configured to operate according to pressure, and this pulp that is configured to operate according to pressure is combined with a stepped piston. It is mounted inside the balance piston to save space. This action of the pulp does not depend on the movement of the balance piston with respect to the body. Therefore, the pulp made to operate in response to pressure is
As long as the first braking circuit is activated, the second braking circuit is always switched at the same pressure, regardless of whether it is activated or not. In contrast, the second braking circuit Therefore, the pressure in the second outlet chamber will not increase after this pulp valve closes.

Preferably, the balancing piston is mounted between identical springs with linear spring characteristics adapted to abut the body.

Based on the characteristics of braking force control devices of the known type (according to a preferred embodiment of the invention, the supplementary pulp is controlled depending on the deceleration state; according to this embodiment of the invention , a second stepped piston is mounted between the second inlet chamber and the outlet chamber coaxially with the balancing piston and movable independently of the balancing piston; On the front side of the smaller one defining the second inlet chamber, a second stepped piston is provided with a pulp valve seat adapted to operate in response to deceleration conditions, and in an abutting position in the resting state. The volume of the second inlet chamber becomes smaller at this abutting position.

An additional feature of the present invention is that the valve attached to the second braking circuit and adapted to operate in response to deceleration conditions does not function as a pressure limiting valve, but rather as a pressure reducing valve. The first braking circuit is made to operate in response to the pressure associated with it, and is equivalent to the Soon pulp. The advantage of configuring both valves as pressure reducing valves is that after both valves are closed, there is no need to move the balancing piston (or even just a slight movement of the balancing piston) between the two outlet chambers. It is possible to balance the pressure at

Hereinafter, two embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The braking force adjusting device shown in FIG.
There are stepped holes in the.

The axis of this hole is hereinafter referred to as the longitudinal axis 12. The braking force adjustment device according to the present invention is arranged in a state where the longitudinal axis 12 is inclined by about 600 degrees from the horizontal in the plane of the longitudinal direction of the automobile, and the front end of the drawing of the main body is 600 degrees from the horizontal in the plane in the longitudinal direction of the automobile. It is designed to be fixed to a car so that it is higher than the rear end of the main body 10.In order to fix it as described above, a bolt (not shown) is inserted into the side hole 14 formed in the main body 10. has been done.

A stepped hole is machined from the front into the body 10 along the longitudinal axis 12, with a front threaded section 18 closed with a threaded plug 16 and a threaded section 18 connected to the threaded section 18. It consists of a front cylinder section 20 with a diameter only slightly smaller than the inside diameter of the cylinder, a central cylinder section 22 dimensioned to an average diameter, and a rear cylinder section 24 of the smallest diameter.

The central region of the front cylinder section 20 forms a first inlet chamber 26 .
The first main cylinder H, which is only indicated by an arrow, passes through the main cylinder connecting line 28.
It is now possible to connect to zI. The front region of the front cylinder compartment 20 has a first outlet chamber 6
0", and the first outlet chamber 60 passes through a brake connection line 62 to a first wheel brake cylinder Rz, which is also mounted on the rear wheel and is also indicated only by an arrow.
It is now possible to connect to I. A vent chamber 64 is provided near the rear end of the front silicider compartment 20 and is in communication with the atmosphere via a dust filter 66.

A second inlet chamber 68 is formed at the rear end of the rear cylinder compartment 24, which is also indicated only by an arrow through a second main cylinder connecting line 40. Second main cylinder Hz
It is now possible to connect to II. Furthermore, the front end of the central cylinder section 22 cooperates with the rear end of the front cylinder section 20 to form a second outlet chamber 42, which is connected to a second brake connection conduit 44. Through this, it is possible to connect to a second wheel brake cylinder Rzn, which is also connected to the second rear wheel of the motor vehicle, which is also indicated only by an arrow.

Two stiff springs 46 and 4 in the front cylinder compartment 20
8 is added, the front spring 46 of these two springs rests on the threaded plug 16, while the rear spring 48 rests on the perforated plate provided between the cylinder compartments 20 and 22. It is in contact with 50. both springs 46 and 48
The balance piston 52 (slightly axially biased)
is installed. The two springs 46 and 48 can, for example, be designed as cross-shaped leaf springs with a linearly ascending characteristic curve that indicates the relationship between the deflection and the applied force. This means that when the oscillating balance piston 52, which is located between both springs, is displaced in the axial direction, the spring only exerts a small return force on the balance piston 52, and the braking operation is completed. After that,
This return force acts to move the balance piston 5 to the center position shown in the figure.
It means that you can return 2.

The balance piston 52 has six rings along its outer circumferential surface.
backings 54, 56, 58, these six ring backings isolate the first inlet chamber 26 from the first outlet chamber 30 and isolate the first inlet chamber 26 from the second outlet chamber 42. It serves to isolate. The balancing piston 52 is made hollow and has a bushing 60 with an axial bore 62 fixed to its front end. First stepped piston 64
The front section, which has the largest diameter, is inserted into the axial hole 62.A hole 66 is formed in the rear portion of the balancing piston 52, which is closed at the rear end.
6 is sized smaller than the diameter of said axial bore 62 such that the rear section of the stepped piston 64 is inserted into the bore 66. The stepped piston 64 is a ring
Backings 68 and 70 are used to keep holes 62 and 66 from leaking. The area of hole 66 located behind ring backing 70 communicates with outside air through vent chamber 64 and filter 66.

A helically wound compression spring 82 having a conical shape at the front and a cylindrical shape at the rear is housed within the balance piston 52 around the first stepped piston 64;
The rear end abuts against the balance piston 52, and the front end abuts against the stepped piston 64.
4 is biased to be held in contact with the front wall 84 of the bushing 60, which has a hole in it. A ring-shaped valve seat 86 made of an elastic material is fixed to the front end of the stepped piston 64, and the valve seat 86 is a valve body axially movably guided within the stepped piston 64. Pulp 86.88 operating in response to pressure in cooperation with 88
is formed. The valve body 88 is biased forward by a spiral compression spring 90 mounted within the stepped piston 64 and includes a front abutment portion 92.
The front abutment portion 92 is attached to the front front wall 84 in the illustrated rest position.
Since the valve body 88 is in contact with the valve seat 86, the valve body 88 is separated from the valve seat 86.

A second stepped piston 94 is interspersed between the central cylinder section 22 and the aft cylinder section 24, with ring backings 96 and 98 keeping both sections 22 and 24 leak-tight. The front face 100 of the second stepped piston 94 cooperates with the counterbalance piston 52 to define the second outlet bumper 42 . A rear front face 102, which is smaller in area than the front front face 100, defines a second inlet chamber 68. This rear front 102
A ring-shaped valve seat 104 made of a resilient material is fixed, which cooperates with a valve body 106 to form pulps 104, 106 that operate in response to deceleration conditions. In the embodiment shown in FIG.
6 is designed as a ball and the second stepped piston 9
4 and are disposed so as to be movable in the axial direction in a cage 108 fixed at 4.

The second stepped piston 94 extends through the passage 11 in the axial direction.
0, the passage 110 opens at the valve seat 104 and contains a bottle 112. The pin 11
2 rests against the perforated plate 50, but the rest position shown, in which the second stepped piston 94 rests against a ring-shaped shoulder 114 formed between the cylinder sections 22 and 24, is changed to a second position. The stepped piston 94 is sized so that it does not reach the valve seat 104 when occupied.

Exhaust holes 116 extend from shoulder 114 and communicate with the atmosphere.

In explaining the operating mode of the braking force adjustment device shown in FIG. I want to come, knowing that being there is a prerequisite. Operating both main cylinders HzI and HzII (usually mounted in a common casing), the pulp 86.88 is adapted to operate according to pressure and the deceleration is adapted to operate according to conditions. Both pulps 104 and 106 opened. Along with this, the entrance chamber 2
The gradually increasing pressure within 6 and 68 is transmitted to the outlet chambers 50 and 42 without reducing the pressure.

When the pressure rises to a certain level and the vehicle decelerates, the spherical valve body 106 rolls forward in the cage 108 and comes into contact with the valve seat 104, so that it Pulp 10 made to work
4.105 closes. However, exit chamber 6
As the pressure inside the vehicle increases, the stepped piston 64 is displaced backward, and the valve seat 86 comes into contact with the valve body 88, so that when the vehicle is in an unloaded state, the stepped piston 64 is displaced backwards, and the valve seat 86 is brought into contact with the valve body 88. Pulp 86.8 adapted to operate in response to pressure substantially simultaneously with pulps 104, 106 adapted to operate.
The spring characteristics of spring 82 are selected so that valve 8 closes. If one of the two pulps closes before the other, movement of the balance piston 52 is blocked, which creates a pressure difference in both outlet chambers 60 and 42.

As the pressure within both inlet chambers 26 and 68 increases further, the pulp 86 is adapted to operate in response to pressure.
j88 acts as a pressure reducing valve when connected to the first stepped piston 64, which has an inlet-to-chamber 28 The pressure within the outlet chamber 60 can only be increased to a lesser extent than the increased pressure within. Similarly, the pulp 104, 106 adapted to operate in response to deceleration conditions also acts as a pressure reducing valve when connected to the second stepped piston 94;
The stepped piston 94 has an effective front face 100 and 102 . of the second stepped piston 94 . The pressure in the second outlet chamber 42 can only be increased to a lesser extent than the pressure in the second inlet chamber 68 based on the area ratio of .

When a heavy load is applied to the motor vehicle, the first stepped piston 64 is displaced rearwardly, creating a pressure increase in the outlet chamber 60 which causes the pressure-operated pulp 86, 88 to close. and 42, so that the vehicle does not suddenly decelerate, so that the pulps 104, 106, which are adapted to operate in response to deceleration conditions, remain closed. Therefore, the increased pressure of the second main cylinder Hz II is transmitted to the outlet chamber 42 without any depressurization (the resulting balance piston 5 towards the front).
2, to the same extent as inside the exit chamber 42,
The pressure inside the 4#l rotary jumper 60 increases. 1 Supplying a higher pressure to both wheel brake cylinders RzI and Rzf[, the vehicle decelerates and the pulp 104.10<S adapted to operate according to the deceleration condition closes and the pressure in the outlet chamber 42 As the pressure increases further,
As the balance piston 52 moves, the inlet chamber 26
The pressure also increases in the outlet chamber 60, although the rate of increase in pressure is lower than that in the chambers 28 and 28.

In the event of a failure of the first brake circuit HzI RzI, the balance piston 52 moves to the front end position limited by the plug 16 with each braking operation, and the outlet chamber 42 receives a correspondingly larger amount of brake fluid. , the driver knows that the first braking circuit is faulty because the brake pedal must be depressed more deeply than before. Adjust the inclination angle of the longitudinal axis 12 with respect to the horizontal. By this, when the selected deceleration time has elapsed,
Pulp 104 adapted to operate in response to deceleration conditions.
106 closes. However, if the pressure in the inlet chamber 68 increases further, the second stepped piston 94 will move earlier than when the first brake circuit HzI-RzI is activated, and the pin 11.2 will accordingly Body・106
is lifted from the valve seat 104, so that the pressure in the outlet chamber 42 is again balanced with the pressure in the inlet chamber 68, and accordingly the rear wheel corresponding to the wheel brake cylinder RzI[ is activated in the first brake circuit. In some cases, it will be more forceful (braking will occur).

If, on the other hand, the second braking circuit HzII-RzII fails, then with each braking operation the balance piston 52 moves to the rear end position set by the perforated plate 50, which is located at the sixth extension in the drawing. However, pulps 86,88 made to operate in response to pressure operate normally.

The braking force adjustment device shown in FIG. 2 with a modified configuration differs from the embodiment shown in FIG. Only. In this variant embodiment, the cylinder compartment 22 extends further towards the rear, and a bushing 118 whose internal diameter is dimensioned smaller than the internal diameter of the cylinder compartment 22 enters the body 10 from the rear. inserted and secured to prevent leakage. Stepped piston 120 within cylinder compartment 22 and bushing 118
is inserted, but the configuration and dimensions of the stepped piston 120 are the same as the configuration and dimensions of the stepped piston 64. Stepped piston 64 shown in FIG.
1 between the first inlet chamber 26 and the first outlet chamber 60 under the control of the pulp 86j88 which is adapted to operate in response to pressure, as in the embodiment shown in FIG. Although adapted to communicate, the stepped piston 120 connects the second inlet chamber 68 and the second outlet chamber 42 under the control of the pulps 122, 124 adapted to operate in response to pressure.
We are communicating with each other. A ring-shaped valve seat 122 is fixed to the front end of the stepped piston 120, and a valve seat 124 is inserted in the stepped piston 120 so as to be able to move in the axial direction.
are pulps 122, 124. belongs to the valve body 1, and the valve body 1
24 is similarly biased toward the valve seat 122 by a spring 126 mounted within the stepped piston 120 and includes a front stop 128. In the illustrated rest position, the stopper 128 rests against the perforated plate 50 and the valve body 124 is spaced from the valve seat 122.

A lever 162 is pivotally supported on a bearing pin 160 extending perpendicularly to the longitudinal axis 12 at a position spaced apart from the longitudinal axis 12 at the rear end of the main body 10. A spring indicated by an arrow 164 is attached to the lower end of the lever 162. The spring 164 is connected to the vehicle axle in a known manner to adjust the lever 132 in the direction of arrow 13- as the load increases. An adjustment bolt 136 is threaded onto the lever 132 substantially coaxially with the longitudinal axis 12 and secured using a hexagonal nut 138. The adjusting bolt 166 is sealed using a sealing member 140 to prevent leakage from the main body 10 and the bushing 118, and its end abuts against the rear front surface of the stepped piston 120. Both the lever 162 and the adjusting bolt 166 are shown in positions corresponding to a relatively low load condition of the motor vehicle.

When the pressure in the second inlet chamber 68 (as well as in the first inlet chamber 26) increases significantly due to the braking operation, said pressure passes through the opened pulp 122 and 124 to the second inlet chamber 68 (as well as the first inlet chamber 26).
is transmitted to the outlet chamber 42 of. Exit chamberer 4
When the pressure in the stepped piston 2 exceeds a preset value by adjusting the spring, the stepped piston 120 will move backwards against the resistance of the spring 134 due to the difference in force acting on the stepped piston 120. Since the valve seat 122 is displaced toward the right side as viewed in FIG.
, and communication between the second inlet chamber 68 and the second outlet chamber 42 is interrupted. As the pressure within the inlet chamber 38 increases further, the stepped piston 120 again moves slightly forward, causing the pulps 122 and 124 to momentarily open and the inlet chamber 68
As the pressure inside increases, the stepped screw 5 tons 120
The pressure within the outlet chamber 42 increases according to a ratio corresponding to the ratio of the effective frontal areas of the .

However, when the load applied to the automobile increases and the load applied to the spring 164 increases accordingly, the spring 164 rotates approximately 2.6 degrees clockwise from the illustrated position to the position VCVA.
Holds -15□. In fact, when no braking is applied, the stepped piston 120 occupies a starting position that is slightly shifted forward from the position shown, that is, to the left in FIG. Apply braking and inlet chamber 68
As the pressure within the outlet chamber 42 increases, the valve seat 12
2 reaches the valve body 124, the stepped piston 120
It is necessary to increase the pressure considerably to move it backwards. When the vehicle is under a relatively high load, the pressure within the outlet chamber 42 is relatively high.
Pulps 122 and 124 close only when the ζ level is reached. The lubricant 122, 124 is also a pulp adapted to operate according to the load of the automobile, replacing the pulp 104, 106, which is adapted to operate according to the deceleration state of the automobile shown in FIG. .

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken in the axial direction of a braking force adjustment device according to the present invention, and FIG. 2 is a sectional view taken in the axial direction of a braking force adjustment device having a modified configuration shown in FIG. 1. . 10...Holding 12...Longitudinal axis 14...Horizontal hole 16...
Screw plug 18...Screw section 20.
...Front cylinder lK picture 22...Center cylinder section 24...Rear cylinder section 28...Main cylinder connection pipe 30...
. . . First outlet chamber 52 --- Brake connection conduit 34 --- Air vent chamber 36 ---
...Dust filter 68...Second inlet chamber 40...Second main cylinder connection line 42...Second outlet chamber 4
4...Second brake connection pipe 46.48...Spring 50...
Perforated plate 52...Equilibrium piston 54.56. '58...Ring Φ backing 6
0... Bush 62... Axial hole 64... First stepped piston 66...
·hole

Claims (1)

[Claims] (1) A braking force adjustment device for an automobile hydraulic braking device comprising a main body (10), which includes first and second inlet chambers (26, 28) and a first and second inlet chamber (26, 28). The second outlet chamber (30, 42) connects the first and second damping circuits (HzI -1'1.zI and Hzll -R,zH
) and both outlet chambers (30,
42) are separated from each other by a balance piston (52), the first inlet chamber and the outlet chamber C26,6
A stepped piston (64) is provided between the
The larger front face of the stepped piston (64) defines a first outlet chamber (C60) and is oriented by a spring (82) to reduce the volume of the first outlet chamber (60).
energizes the first outlet chamber (60), and further energizes the first inlet chamber and the outlet chamber (26).
, 50) are fitted with valves (86, 88) which are pressure-dependently controlled by the position of the stepped piston (64) with respect to the counterbalancing piston (52), and which are connected to the second inlet chamber and the outlet chamber C5B, 42), in which a further brake tll/(k 7' (104, 106) is provided between the stepped pistons (64, 106).
) biases the stepped piston (64) (82);
and valves (86, 8
Valves (86, 88) are mounted in the balance piston (52) together with the stepped piston (64) and are adapted to operate in response to the pressure of the stepped piston (64).
A braking force adjustment device characterized in that it is controlled by a stepped piston (64) that is independent of the position of the equilibrium piston (52) with respect to (2) the control according to claim 1; The power regulating device is characterized in that the balance piston (52) is mounted between two identical springs (46, 48) with linear spring characteristics which are brought into abutment against the body (10). Braking force adjustment device*. f31 Second inlet chamber and outlet chamber (3
8, 42) is a valve (104, 106) controlled according to the deceleration state, in the braking force adjusting device according to claim 1 or 2, between the inlet chambers (38, 42) of the balance piston (52) and coaxial with the balance piston (52).
) a second stepped piston (94) is movably mounted to define a second inlet chamber (38) of the second stepped piston (94); A second stepped piston (94) is provided on the smaller front side (102) of the valve seat of the valve (104, 106), which is adapted to operate depending on the deceleration state, and is in abutment in the stationary state. The braking force adjusting device is characterized in that the volume of the second inlet chamber (68) is the smallest in this abutting position.