Brake power boosting mechanism

Claim 2

A brake force servo-installation including an actuating means, servo and adjusting means operatively connected with said actuating means, a master cylinder means acted upon by said actuating means, filling means operatively connected with said actuating means, master cylinder means and said servo and adjusting means, control and shifting means operatively connected with said actuating means, said master cylinder means, and said filling means, and a brake pedal lever pivotally connected to the filling means and the actuating means, characterized in that the actuating means includes an actuating piston having a piston rod, the filling means are separated from said actuating means and includes a filling cylinder space means for accommodating a hydraulic fluid, a filling piston means for controlling a volume of the filling cylinder space means, and a piston rod, the brake pedal lever includes a first and second end with a brake pedal mounted at said first end, means are provided for pivotally connecting said second end of said brake pedal lever with said piston rod of said filling piston means, means are provided for pivotally connecting said brake pedal with said piston rod of said actuating piston at a position on said brake pedal lever between said brake pedal and the pivotal connection of the brake pedal lever with said piston rod of said filling piston means, the master cylinder means includes master piston means displaceably arranged in a master piston housing, said servo and adjusting means includes an actuating servo-piston having a smaller cross-section than a cross-section of said master piston means and pressure hydraulic fluid receiving spaces, a connecting space means arranged between said master piston means and said actuating servo-piston for defining a pressure space between said actuating servo-piston and said master piston means, the control and shifting means includes a housing, a displaceably mounted control piston means arranged in a bore provided in the housing, said control piston means and said bore are so configured so as to define a plurality of pressure spaces, first bore means for communicating a first of said plurality of pressure spaces with said connecting space means, second bore means for communicating a second of said plurality of pressure spaces with said filling cylinder space means, third bore means for communicating a third pressure space of said plurality of pressure spaces with the pressure fluid receiving spaces of said servo and adjusting means, said control piston means including an end face which defines with a portion of said housing a fourth pressure space, further bore means provided in said control piston means for communicating said fourth pressure space with said second bore means so as to provide a supply of hydraulic fluid to said fourth pressure space, spring means for normally biasing said control piston means in a direction opposite a direction of displacement of said control piston means by the hydraulic fluid, line means for communicating said third pressure space with a return tank, means provided on said control piston means and said bore in which said control piston means is arranged for closing said third pressure space from said line means upon reaching a first predetermined interior pressure in said fourth pressure space which displaces the control piston means against the force of said spring means such that the pressure hydraulic fluid receiving spaces of said servo and adjusting means, said third bore means and said third pressure space form a rigid fluid column thereby preventing said actuating piston and said actuating servo-piston from acting upon the master piston means whereby the pivotal connection of said brake pedal lever with said piston rod of said actuating piston is effective as a fixed pivot point of the brake pedal lever, and in that, upon a further displacement of said control piston means, said closing means opens said third pressure space and closes said first pressure space from said filling cylinder space means such that said filling cylinder space means and said fourth pressure space form a rigid fluid column preventing said filling piston means from moving thereby resulting in a shift of the point of pivotal connection of the brake pedal lever from the pivotal connection of the brake pedal lever with the piston rod of said actuating piston to the pivotal connection of said brake pedal lever with said piston rod of said filling piston means, and in that, after a shifting of the point of pivotal connection, hydraulic fluid, supplied from a pump means, is effective upon an end face of the actuating servo-piston facing the brake pedal so as to displace the actuating servo-piston in a direction toward the master piston means thereby automatically shifting from a first brake pedal lever ratio to a different brakepedal lever translation ratio.

Claim 3

A brake force servo-installation according to claim 1, characterized in that upon a closing of said third pressure space from said line means, a translation ratio of about 1 : 1 is obtained, and in that upon reopening of said third pressure space and the shifting of the point of pivotal connection, a translation ratio of about 1 : 6 is obtained.

Claim 4

A brake force servo-installation including an actuating means, servo and adjusting means operatively connected with said actuating means, a master cylinder means acted upon by said actuating means, filling means operatively connected with said actuating means, master cylinder means and said servo and adjusting means, control and shifting means operatively connected with said actuating means, said master cylinder means and said filling means, and a brake pedal lever pivotally connected to the filling means and the actuating means, characterized in that the actuating means includes an actuating piston having a piston rod, the filling means are separated from said actuating means and includes a filling cylinder space means for accommodating a hydraulic fluid, a filling piston means for controlling a volume of the filling cylinder space means, and a piston rod, the brake pedal lever includes a first and second end with a brake pedal mounted at said first end, means are provided for pivotally connecting said second end of said brake pedal lever with said piston rod of said filling piston means, means are provided for pivotally connecting said brake pedal lever with said piston rod of said actuating piston at a position on said brake pedal lever between said brake pedal and the pivotal connection of the brake pedal lever with said piston rod of said filling piston means, the master cylinder means includes master piston means displaceably arranged in a master piston housing, said servo and adjusting means includes an actuating servo-piston having a smaller cross-section than a cross-section of said master piston means and pressure hydraulic fluid receiving spaces, a connecting space means arranged between said master piston means and said actuating servo-piston for defining a pressure space between said actuating servo-piston and said master piston means, the control and shifting means includes a housing, a displaceably mounted control piston means arranged in a bore provided in the housing, said control piston means and said bore are so configured so as to define a plurality of pressure spaces, first bore means for communicating a first of said plurality of pressure spaces with said connecting space means, second bore means for communicating a second of said plurality of pressure spaces with said filling cylinder space means, third bore means for communicating a third pressure space of said plurality of pressure spaces with the pressure fluid receiving spaces of said servo and adjusting means, said control piston means including an end face which defines with a portion of said housing a fourth pressure space, further bore means provided in said control piston means for communicating said fourth pressure space with said second bore means so as to provide a supply of hydraulic fluid to said fourth pressure space, spring means for normally biasing said control piston means in a direction opposite a direction of displacement of said control piston means by the hydraulic fluid, line means for communicating said third pressure space with a return tank, means provided on said control piston means and said bore in which said control piston means is arranged for closing said third pressure space from said line means upon reaching a first predetermined interior pressure in said fourth pressure space which displaces the control piston means against the force of said spring means such that the pressure hydraulic fluid receiving spaces of said servo and adjusting means, said third bore means and said third pressure space form a rigid fluid column thereby preventing said actuating piston and said actuating servo-piston from acting upon the master piston means whereby the pivotal connection of said brake pedal lever with said piston rod of said actuating piston is effective as a fixed pivot point of the brake pedal lever, and in that, upon a further displacement of said control piston means, said closing means opens said third pressure space and closes said first pressure space from said filling cylinder space means such that said filling cylinder space means and said fourth pressure space form a rigid fluid column preventing said filling piston means from moving thereby resulting in a shift of the point of pivotal connection of the brake pedal lever from the pivotal connectin of the brake pedal lever with the piston rod of said actuating piston be the pivotal connection of said brake pedal lever with said piston rod of said filling piston means, and in that, after a shifting of the point of pivotal connection, hydraulic fluid, supplied from a pump means, is effective upon an end face of the actuating servo-piston facing the brake pedal so as to displace the actuating servo-piston in a direction toward the master piston means thereby automatically shifting from a first brake pedal lever ratio to a different brake pedal lever translation ratio, and in that a working pressure space means is provided between said actuating piston and said actuating servo-piston, a unilaterally acting ball valve means is provided for controlling a communication between at least one of said pressure-fluid receiving spaces and the working pressure space means, said ball valve means including a ball valve, a valve seat, and a restrained relief spring means supported against the actuating piston means for pressing the ball valve against the valve seat, and in that restraining action on said relief spring means assures an approximately constant abutment pressure of the ball valve against the valve seat with a pressure of the actuating piston means against the actuating servo-piston or with a pressure increase in the working space means.

Claim 5

A brake force servo-installation including an actuating means, servo and adjusting means operatively connected with said actuating means, a master cylinder means acted upon by said actuating means, filling means operatively connected with said actuating means, master cylinder means and said servo and adjusting means, control and shifting means operatively connected with said actuating means, said master cylinder means and said filling means, and a brake pedal lever pivotally connected to the filling means and the actuating means, characterized in that the actuating means includes an actuating piston having a piston rod, the filling means are separated from said actuating means and includes a filling cylinder space means for accommodating a hydraulic fluid, a filling piston means for controlling a volume of the filling cylinder space means, and a piston rod, the brake pedal lever includes a first and second end with a brake pedal mounted at said first end, means are provided for pivotally connecting said second end of said brake pedal lever with said piston rod of said filling piston means, means are provided for pivotally connecting said brake pedal lever with said piston rod of said actuating piston at a position on said brake pedal lever between said brake pedal and the pivotal connection of the brake pedal lever with said piston rod of said filling piston means, the master cylinder means includes master piston means displaceably arranged in a master piston housing, said servo and adjusting means includes an actuating servo-piston having a smaller cross-section than a cross-section of said master piston means and pressure hydraulic fluid receiving spaces, a connecting space means arranged between said master piston means and said actuating servo-piston for defining a pressure space between said actuating servo-piston and said master piston means, the control and shifting means includes a housing, a displaceably mounted control piston means arranged in a bore provided in the housing, said control piston means and said bore are so configured so as to define a plurality of pressure spaces, first bore means for communicating a first of said plurality of pressure spaces with said connecting space means, second bore means for communicating a second of said plurality of pressure spaces with said filling cylinder space means, third bore means for communicating a third pressure space of said plurality of pressure spaces with the pressure fluid receiving spaces of said servo and adjusting means, said control piston means including an end face which defines with a portion of said housing a fourth pressure space, further bore means provided in said control piston means for communicating said fourth pressure space with said second bore means so as to provide a supply of hydraulic fluid to said fourth pressure space, spring means for normally biasing said control piston means in a direction opposite a direction of displacement of said control piston means by the hydraulic fluid, line means for communicating said third pressure space with a return tank, means provided on said control piston means and said bore in which said control piston means is arranged for closing said third pressure space from said line means upon reaching a first predetermined interior pressure in said fourth pressure space which displaces the control piston means against the force of said spring means such that the pressure hydraulic fluid receiving spaces of said servo and adjusting means, said third bore means and said third pressure space form a rigid fluid column thereby preventing said actuating piston and said actuating servo-piston from acting upon the master piston means whereby the pivotal connection of said brake pedal lever with said piston rod of said actuating piston is effective as a fixed pivot point of the brake pedal lever, and in that, upon a further displacement of said control piston means, said closing means opens said third pressure space and closes said first pressure space from said filling cylinder space means such that said filling cylinder space means and said fourth pressure space form a rigid fluid column preventing said filling piston means from moving thereby resulting in a shift of the point of pivotal connection of the brake pedal lever from the pivotal connectin of the brake pedal lever with the piston rod of said actuating piston be the pivotal connection of said brake pedal lever with said piston rod of said filling piston means, and in that, after a shifting of the point of pivotal connection, hydraulic fluid, supplied from a pump means, is effective upon an end face of the actuating servo-piston facing the brake pedal so as to displace the actuating servo-piston in a direction toward the master piston means thereby automatically shifting from a first brake pedal lever ratio to a different brake pedal lever translation ratio, and in that a working pressure space means is provided between said actuating piston and said actuating servo-piston, a unilaterally acting ball valve means is provided for controlling a communication between at least one of said pressure-fluid receiving spaces and the working pressure space means, said ball valve means including a ball valve, a valve seat, and a restrained relief spring means supported against the actuating piston means for pressing the ball valve against the valve seat, and in that restraining action on said relief spring means assures an approximately constant abutment pressure of the ball valve against the valve seat with a pressure of the actuating piston means against the actuating servo-piston or with a pressure increase in the working space means.

Claim 6

A brake force servo-installation according to claim 3, characterized in that a further line means is provided for communicating said third pressure space with said first-mentioned line means, a safety valve means is arranged in said further line for operatively connecting said further line means with the first-mentioned line means upon exceeding a predetermined limit pressure in said third pressure space.

Claim 7

A brake force servo-installation according to claim 4, characterized in that a common housing means is provided for the servo- and adjusting means, the filling means, and the control and shifting means, said control and shifting means being disposed between said servo- and adjusting means and the filling means, and in that the common housing means is assembled with the master cylinder means so as to form a single structural unit.

Claim 8

A brake force servo-installation including an actuating means, servo- and adjusting means operatively connected with said actuating means, a master cylinder means acted upon by said actuating means, filling means operatively connected with said actuating means, master cylinder means and said servo- and adjusting means, control and shifting means operatively connected with said actuating means, said master cylinder means and said filling means, and a brake pedal lever pivotally connected to the filling means and the actuating means, characterized in that the actuating means includes an actuating piston having a piston rod, the filling means are separated from said actuating means and includes a filling cylinder space means for accommodating a hydraulic fluid, a filling piston means for controlling a volume of the filling cylinder space means, and a piston rod, the brake pedal lever includes a first and second end with a brake pedal mounted at said first end, means for connecting said filling means and said actuating means with said control and shifting means so that one of said piston rods is prevented from moving upon an actuation of the brake pedal lever during an idle path with a first brake pedal lever ratio and, upon traversing the idle path, said piston rod is released so as to automatically shift to a different brake pedal lever ratio, and in that the master cylinder means includes master piston means, said servo- and adjusting means includes an actuating servo-piston having a smaller cross-section than a cross-section of said master piston means and pressure hydraulic fluid receiving spaces, a connecting space means arranged between said master piston means and said actuating servo-piston for defining a pressure space between said actuating servo-piston and said master piston means, the control and shifting means includes a housing, a displaceably mounted control piston means arranged in a bore provided in the housing, said control piston means and said bore are so configured so as to define a plurality of pressure spaces, first bore means for communicating a first of said plurality of pressure spaces with said connecting space means, second bore means for communicating a second of said plurality of pressure spaces with said filling cylinder space means, third bore means for communicating a third pressure space of said plurality of pressure spaces with the pressure fluid receiving spaces of said servo- and adjusting means, said control piston means including an end face which defines with a portion of said housing a fourth pressure space, further bore means provided in said control piston means for communicating said fourth pressure space with said second bore means so as to provide a supply of hydraulic fluid to said fourth pressure space, spring means for normally biasing said control piston means in a direction opposite a direction of displacement of said control piston means by the hydraulic fluid, line means for communicating said third pressure space with a return tank, means provided on said control piston means and said bore in which said control piston means is arranged for closing said third pressure space from said line means upon reaching a first predetermined interior pressure in said fourth pressure space which displaces the control piston means against the force of said spring means such that the pressure hydraulic fluid receiving spaces of said servo- and adjusting means, said third bore means and said third pressure space form a rigid fluid column thereby preventing said actuating piston and said actuating servo-piston from acting upon the master piston means whereby the pivotal connection of said brake pedal lever with said piston rod of said actuating piston is effective as a fixed pivot point of the brake pedal lever and in that, upon a further displacement of said control piston means, said closing means opens said third pressure space and closes said first pressure space from said filling cylinder space means such that said filling cylinder space means and said fourth pressure space form a rigid fluid column preventing said filling piston means from moving thereby resulting in a shift of the point of pivotal connection of the brake pedal lever, and in that, after a shifting of the point of pivotal connection, hydraulic fluid, supplied from a pump means, is effective upon an end face of the actuating servo-piston facing the brake pedal so as to displace the actuating servo-piston in a direction toward the master piston means.

Claim 9

A brake force servo-installation including an actuating means, servo- and adjusting means operatively connected with said actuating means, a master cylinder means acted upon by said actuating means, filling means operatively connected with said actuating means, master cylinder means and said servo- and adjusting means, control and shifting means operatively connected with said actuating means, said master cylinder means and said filling means, and a brake pedal lever pivotally connected to the filling means and the actuating means, characterized in that the actuating means includes an actuating piston having a piston rod, the filling means are separated from said actuating means and includes a filling cylinder space means for accommodating a hydraulic fluid, a filling piston means for controlling a volume of the filling cylinder space means, and a piston rod, the brake pedal lever includes a first and second end with a brake pedal mounted at said first end, means for connecting said filling means and said actuating means with said control and shifting means so that one of said piston rods is prevented from moving upon an actuation of the brake pedal lever during an idle path with a first brake pedal lever ratio and, upon traversing the idle path, said piston rod is released so as to automatically shift to a different brake pedal lever ratio, and in that the master cylinder means includes master piston means, said servo- and adjusting means includes an actuating servo-piston having a smaller cross-section than a cross-section of said master piston means and pressure hydraulic fluid receiving spaces, a connecting space means arranged between said master piston means and said actuating servo-piston for defining a pressure space between said actuating servo-piston and said master piston means, the control and shifting means includes a housing, a displaceably mounted control piston means arranged in a bore provided in the housing, said control piston means and said bore are so configured so as to define a plurality of pressure spaces, first bore means for communicating a first of said plurality of pressure spaces with said connecting space means, second bore means for communicating a second of said plurality of pressure spaces with said filling cylinder space means, third bore means for communicating a third pressure space of said plurality of pressure spaces with the pressure fluid receiving spaces of said servo- and adjusting means, said control piston means including an end face which defines with a portion of said housing a fourth pressure space, further bore means provided in said control piston means for communicating said fourth pressure space with said second bore means so as to provide a supply of hydraulic fluid to said fourth pressure space, spring means for normally biasing said control piston means in a direction opposite a direction of displacement of said control piston means by the hydraulic fluid, line means for communicating said third pressure space with a return tank, means provided on said control piston means and said bore in which said control piston means is arranged for closing said third pressure space from said line means upon reaching a first predetermined interior pressure in said fourth pressure space which displaces the control piston means against the force of said spring means such that the pressure hydraulic fluid receiving spaces of said servo- and adjusting means, said third bore means and said third pressure space form a rigid fluid column thereby preventing said actuating piston and said actuating servo-piston from acting upon the master piston means whereby the pivotal connection of said brake pedal lever with said piston rod of said actuating piston is effective as a fixed pivot point of the brake pedal lever and in that, upon a further displacement of said control piston means, said closing means opens said third pressure space and closes said first pressure space from said filling cylinder space means such that said filling cylinder space means and said fourth pressure space form a rigid fluid column preventing said filling piston means from moving thereby resulting in a shift of the point of pivotal connection of the brake pedal lever, and in that, after a shifting of the point of pivotal connection, hydraulic fluid, supplied from a pump means, is effective upon an end face of the actuating servo-piston facing the brake pedal so as to displace the actuating servo-piston in a direction toward the master piston means.

Claim 10

A brake force servo-installation according to claim 6, characterized in that the filling means and the actuating means are arranged separated from one another.

Claim 11

A brake force servo-installation according to claim 7, characterized in that the actuating means is a hydraulic actuating means.

Claim 12

A brake force servo-installation according to claim 7, characterized in that the piston rod of the filling piston means is pivotally connected to said brake pedal lever at said second end, and the piston rod of the actuating piston means is pivotally connected to said brake pedal lever at a position on said brake pedal lever between said first and second end.

Claim 13

A brake force servo-installation according to claim 7, characterized in that the filling piston means is larger in cross section than the master piston means, actuating piston means and servo-piston.

Claim 14

A brake force servo-installation according to claim 6, characterized in that the piston rod of the filling piston means is pivotally connected to said brake pedal lever at said second end, and the piston rod of the actuating piston means is pivotally connected to said brake pedal lever between said first and second end.

Claim 15

A brake force servo-installation according to claim 6, characterized in that the filling piston means is larger in cross section than the master piston means, actuating piston and servo-piston.

Claim 16

A brake force servo-installation according to claim 6, characterized in that return spring means are provided for exerting a pressure on the master piston means, a restrained compensating spring means is accommodated in a space of the filling means for compensating the pressure exerted by said return spring means in an idling path of the brake pedal lever, the restraining action on said compensating spring means permitting the rapid return of the piston means of the master cylinder means for purposes of venting.

Claim 17

A brake force servo-installation according to claim 13, characterized in that aperture means are provided in the space accommodating the compensating spring means for communicating said space with a hydraulic fluid reserve tank so as to avoid a vacuum in said accommodating space.

Claim 18

A brake force servo-installation according to claim 6, characterized in that said spring means normally biasing the control piston means includes a first spring and a second spring, said first spring having a smaller blocking force than said second spring, said blocking force is not overcome until the closing of said third pressure space from said line means, and in that upon an increase in hydraulic pressure, the blocking force of the second spring is overcome with said second spring effecting a restraining action so as to enable the response of the first spring prior to the blocking force of the second spring to be effective.

Claim 19

A brake force servo-installation according to claim 15, characterized in that a spring-receiving space means is provided in the housing of said control and shifting means for receiving said first and second springs, and in that a small aperture means is provided for venting said spring receiving space means.

Claim 20

A brake force servo-installation according to claim 6, characterized in that a line is provided for communicating a pressure space of said control and shifting means with a return tank, and in that a safety valve means is arranged in said line for operatively connecting the pressure space with the return tank upon exceeding a limit pressure in the pressure space.

Claim 21

A brake force servo-installation according to claim 6, characterized in that a common housing means is provided for the servo- and adjusting means, the filling means, and the control and shifting means, said control and shifting means being disposed between said servo- and adjusting means and the filling means, and in that the common housing means is assembled with the master cylinder means so as to form a single structural unit.