Abstract: A vehicle system and method for remote start operation in the vehicle system are provided. The method includes responsive to receiving a remote start request and while the vehicle is stationary, automatically engaging a wheel-arresting device coupled to a wheel in the vehicle. The method also includes when an electronically actuated clutch is automatically disengaged and subsequent to the automatic engagement of the wheel-arresting device, implementing remote start operation in an engine, where the wheel-arresting device is distinct from a secondary vehicle brake.

Abstract: A lever assembly for a bicycle may be adjustable. The lever assembly may include an anchoring member, a rod coupled to the anchoring member, and a retaining device applying a clamping force to the anchoring member. The retaining device may include a first extension and a second extension configured to obstruct rotation of the rod about a longitudinal axis of the rod.

Abstract: A brake booster includes an input element actuatable by a driver, an actuator for generating a support force, an output element that receives at least one of an input or support force and that applies an actuating force to a piston of a brake master cylinder, a force transmission unit having elastic properties and transmitting the input and/or support forces to the output element, and a preload unit acting on the force transmission unit to apply a force couple to the force transmission unit when the brake booster is in idle mode. A method for operating the brake booster includes generating a support force prior to a braking intent to be anticipated or immediately after detection of a braking intent, in a time span before or immediately after detection of an actuation of the input element.

Abstract: A brake booster includes an input element actuatable by a driver, an actuator for generating a support force, an output element to which an input or support force may be applied and via which an actuating force may be applied to a piston of a brake master cylinder, and a force transmission unit having elastic properties, situated between the input element and the actuator, and the output element, and transmitting the input and/or support forces to the output element. An air gap, which in idle mode is smaller or larger than a desired air gap, is provided between the input element and the force transmission unit. A method for operating the brake booster includes generating a support force prior to a braking intent to be anticipated or immediately after detection of a braking intent, in a time span before or immediately after detection of an actuation of the input element.

Abstract: In an electric motor-driven booster, a sharp change of reaction force to an operation of a brake pedal is reduced to improve the brake pedal operation feeling. Operation of the brake pedal causes an input rod (34) and an input piston (32) to advance, and an electric motor (40) is driven according to the movement of the input piston to propel a primary piston (10) through a ball-screw mechanism, thereby generating a desired brake hydraulic pressure in a master cylinder. At this time, the input piston receives the hydraulic pressure in the master cylinder to feed back a part of reaction force during braking to the brake pedal. When the brake pedal is further depressed after the output of the electric motor has reached a maximum output and the primary piston 10 has stopped, a lock nut abuts against a movable spring retainer and compresses a reaction force spring.

Abstract: The present disclosure relates to various vehicle braking assemblies. Brake pedal arms include, for example, a cam block that is configured to simplify the engagement between the power booster and pedal arm. Cam block can be movable with respect to the pedal arm to manage the gap between the pedal arm and power booster in by-wire braking assemblies.

Abstract: When a brake switch is switched from OFF to ON, current is applied to a brake ECU, and a command to switch a master cylinder from a second state to a first state is issued after a lapse of preparation time, so that switching-time change suppression control is performed. A reservoir shutoff valve is closed, and duty control is performed on a communication control valve. The duty ratio is set to 1 when a switching-time control duration expires, and the communication control valve is placed in an open position, to establish the first state. Thus, since the communication control valve is duty-controlled during switching from the second state to the first state, change in the hydraulic pressure of an input chamber is suppressed, and change of the operating feeling is suppressed.

Abstract: Provided is a stroke simulator in which the piston operates smoothly without being inhibited from displacement thereof by the negative pressure generated in the closed space, even if the piston is configured to be displaced so as to close the space in which the elastic member is housed, and to elastically deform the elastic member. A stroke simulator, in which a simulator piston presses a first return spring, which is housed in a bottomed cylindrical portion, from an opening portion side of the cylindrical portion, to cause the first return spring to be elastically deform, and to generate a brake reaction force. When the opening portion is closed by the simulator piston, a brake fluid filled in the cylinder portion is taken into the inside of the cylindrical portion via a flow path leading to the inside of the cylindrical portion from a second cylinder.

Abstract: Disclosed is a hydraulic brake booster. A relative movement structure of a control plunger and an output shaft is modified in such a manner that the output shaft operates in the control plunger, thereby reducing the overall length of the booster and the manufacturing cost. An inner circumferential surface of a guide of the control plunger does not make contact with an outer circumferential surface of the output shaft, so that the vibration and the impact caused by the contact between the control plunger and the output shaft are not delivered, thereby improving brake pedal feeling. The control plunger includes a guide having a groove, and an inner diameter of the guide is greater than an outer diameter of the output shaft. The control plunger and the output shaft perform relative movement in the overlap state therebetween, thereby reducing the overall length of the booster and the manufacturing cost.

Abstract: A vehicular hydraulic-pressure-generation device wherein a first bush compressively deforms due to pressure from a simulator piston that moves when hydraulic pressure produced when a brake pedal is depressed is transmitted into a cylinder part. Said vehicular hydraulic-pressure-generation device thus creates artificial reaction-force characteristics with respect to the position of the brake pedal. The aforementioned first bush has a third elastic modulus, which is smaller than a second elastic modulus, and is provided in parallel with a first return spring. The compressive deformation of the first bush occurs over a second region that overlaps a first region in which compressive deformation of the return spring primarily occurs. This makes the brake pedal move more smoothly, reducing the feeling of incongruity resulting from a V-shaped singularity in the reaction-force characteristics with respect to brake pedal position.

Abstract: A vehicular hydraulic-pressure-generation device wherein a first bush compressively deforms due to pressure from a simulator piston that moves when hydraulic pressure produced when a brake pedal is depressed is transmitted into a cylinder part. Said vehicular hydraulic-pressure-generation device thus creates artificial reaction-force characteristics with respect to the position of the brake pedal. The aforementioned first bush has a third elastic modulus, which is smaller than a second elastic modulus, and is provided in parallel with a first return spring. The compressive deformation of the first bush occurs over a second region that overlaps a first region in which compressive deformation of the return spring primarily occurs. This makes the brake pedal move more smoothly, reducing the feeling of incongruity resulting from a V-shaped singularity in the reaction-force characteristics with respect to brake pedal position.

Abstract: Disclosed herein is a pedal simulator for an active brake system. The pedal simulator includes a simulator block provided therein with a bore, a first reaction unit including a first reaction piston slidably installed in the bore, a first damping member installed at the first reaction piston, and a first reaction spring compressed by the first reaction piston, and a second reaction unit including a second reaction piston provided in the bore to support the first reaction spring and slide in the bore, a damping housing connected to the simulator block to be spaced a certain distance apart from the second reaction piston, a second reaction spring installed between the second reaction piston and the damping housing to be compressed by the second reaction piston, and a second damping member installed in the damping housing to contact the second reaction piston.

Abstract: The invention relates to a method for operating a brake boosted brake system of a vehicle, comprising the monitoring of a mode of operation of the brake boosted brake system with regard to agreement of a total braking torque applied to at least one wheel of the vehicle by the brake boosted brake system with a specified target total braking torque and/or with regard to a displacement of a brake medium volume of the brake boosted brake system to a force/pressure conversion element (22) of the brake boosted brake system, if a braking torque difference between the applied total braking torque and the specified target total braking torque is greater than a specified reference difference, and/or if the brake medium volume displaced to the force/pressure conversion element (22) is larger than a specified reference volume; further comprising the defining of a target boosting force change with regard to a boosting force (Fu) provided by a brake booster (14) of the brake boosted brake system, taking into account the br

Abstract: Disclosed herein is a pedal simulator for an active brake system. The pedal simulator includes a simulator block provided therein with a bore, a first reaction unit including a first reaction piston slidably installed in the bore, a first damping member installed at the first reaction piston, and a first reaction spring compressed by the first reaction piston, and a second reaction unit including a second reaction piston provided in the bore to support the first reaction spring and slide in the bore, a damping housing connected to the simulator block to be spaced a certain distance apart from the second reaction piston, a second reaction spring installed between the second reaction piston and the damping housing to be compressed by the second reaction piston, and a second damping member installed in the damping housing to contact the second reaction piston. The second damping member is configured with an upper damper and a lower damper.

Abstract: A brake system with a master cylinder, a first piston which is coupled to a brake pedal via a push rod transmitting actuating forces, a second piston which can be actuated by the first piston and which can be brought into force-transmitting connection to a third piston, via which the master cylinder is actuated, at least one elastic element which forms a pedal travel simulator which, in the “brake-by-wire” operating mode, gives the vehicle driver a pleasant pedal sensation, an interspace capable of being acted upon with hydraulic pressure, between the second and the third piston, the action of pressure upon the interspace loading the second and the third piston in opposite directions, a pressure supply device which has a high-pressure source and which allows both a filling of the interspace with pressure medium and emptying thereof, and a valve device for varying pressure fed in the interspace.

Abstract: A vehicle brake system comprises a master brake cylinder having an input piston and master piston and connected to a wheel brake device, a reaction force generating device for generating a reaction force pressure corresponding to a displacement amount of the input piston, a change over valve provided in an open passage branched from a hydraulic conduit connecting the reaction force generating device to the reaction force chamber defined by the input piston and the change over valve connected to a reservoir, a brake force boosting device for applying an assisting pressure to a master piston, an assisting pressure limit judging portion for judging whether the assisting pressure has reached to an assisting limit pressure, and a change over controlling portion for changing over the change over valve to an open state when the assisting pressure limit judging portion judges that the assisting pressure has reached the assisting limit pressure.

Abstract: An annular sealing member 95 for establishing sealing between a boosted hydraulic pressure application chamber 22 and an input-side annular chamber 93 formed between a casing and a backup piston 64A and connected to a hydraulic pressure source is disposed between the casing and the backup piston 64A, and communication passage 216 for establishing communication between the input-side annular chamber 93 and the boosted hydraulic pressure application chamber 22 as the backup piston 64A moves forward by a predetermined stroke or more is provided in one of the backup piston 64A and the casing.

Abstract: The invention relates to a pedal simulation device for simulating the reaction behavior of a pedal, in particular of a brake pedal of a vehicle brake system, comprising a cylinder, a piston disposed displaceably inside the cylinder and coupled to the pedal and delimiting a working chamber inside the cylinder, a resetting element which, upon an actuation of the pedal, exerts a resetting force on the pedal, and a modelling device, which is fluidically connected to the working chamber, for influencing the reaction behavior of the pedal. In the invention, for achieving the reaction behavior it is provided that, upon an actuation of the pedal, by means of the modelling device a vacuum, which is arising or has arisen in the working chamber, is built up.

Abstract: A vehicle braking apparatus includes: a control piston configured to operate so that a reaction force based on the fluid pressure of the boosted fluid pressure application chamber is balanced with a braking operation input from the brake operation member; an elastic member including: a first face adapted to contact with a simulator piston connected to the brake operation member and slidably accommodated in the control piston; and a second face; a sliding member adapted to contact with the second face, the sliding member being accommodated in the control piston; a spring disposed between the sliding member and the control piston; and an odd-shaped portion disposed at least one of the first and second faces of the elastic member, the odd-shaped portion configured to increase a contacting area of the elastic member and at least one of the simulator piston and the sliding member.

Abstract: A bicycle hydraulic brake actuation device includes a hydraulic master cylinder housing having a bore, a master piston and a radial seal received in the bore a push rod and a lever. The push rod is configured to move the master piston and the radial seal between a neutral position and a braking position. The lever is pivotally attached to the housing for pivotal movement between an at rest position and a brake actuation position. The lever includes a contact surface configured and arranged to move the push rod as the lever is pivoted between the at rest position and the brake actuation position. Further, the push rod includes at least one roller configured to contact to the contact surface of the lever.

Abstract: An impedance shaping element (or more simply, an impedance shaper) physically alters or shapes the mechanical impedance of a drive system as it appears from an interface and facilitates use of feedback control to improve performance by altering or shaping a dynamic coupling between an interface and a control system. For example, the impedance shaper can be used to adjust a coupling value from a first value to a second different value. In one embodiment, an impedance shaper controls the compliance, damping and inertia characteristics of fluid within a fluid path.

Abstract: In a brake hydraulic pressure generating device in which the brake operating force is applied to a pressure adjusting valve through a stroke simulator and the hydraulic pressure supplied from the hydraulic pressure source is adjusted to a value corresponding to the brake operating force, during return of the brakes, the return stroke before the brake hydraulic pressure begins to drop is large, so that the brake feeling is bad. This invention proposes a solution to this problem. Hysteresis is imparted to the stroke simulator so that the output hydraulic pressure of the pressure adjusting valve for the stroke of the simulator piston stroke during increase of the brake operating force will be higher than that during reduction of the brake operating force by setting the sliding resistance of the simulator piston greater than that of the input piston.

Abstract: A more reliable hydraulic brake device is proposed which is capable of regenerative cooperative control and eliminates wasteful consumption of electric power. In a hydraulic brake device capable of regenerative cooperative control, a hydraulic pressure adjusting device is provided to adjust the hydraulic pressure in the auxiliary hydraulic chamber to a desired value that is above the output hydraulic pressure value of the pressure adjusting valve. During regenerative cooperative control, the output hydraulic pressure of the pressure adjusting valve is supplied to the auxiliary hydraulic chamber as it is. During non-regenerative cooperative control the output hydraulic pressure of the pressure adjusting valve is increased corresponding to regenerative braking force and supplied to the auxiliary hydraulic chamber.

Abstract: Braking device including a master cylinder (2), a primary piston (3), a control member (4), a booster (6) coupled to the control member (4), and an assist valve (VA) defined by a reaction piston (17) with a bore (18) therein for receiving a ratio control member (24). The control member (24) has a piston (29) with a head (25) located in a chamber (26) between the reaction piston (17) and a bushing (27) retained in the bore (18). The bushing (27) has an axial passage (28) that receives a head (25) of piston (29) to form a valve (36) for closing an inlet to a passage (30) in the piston (29). The bushing (27) slides within bore (18) to limit a pressure difference between the chamber (26) and a front part (18a) of the bore (18) to a value below a pressure difference that causes the valve (36) to open.

Abstract: A braking device for a motor vehicle, including a master cylinder (2) with a primary piston (3) subjected to an actuating force of an input force exerted by a manual operating member (4) and a boost force exerted by a booster (6) coupled to the manual operating member (4) and an emergency assist valve (VA). Valve (VA) comprises: a reaction piston (19) sliding in a bore (20) of the primary piston (3) and urged toward a position of rest by by an elastic return member (22); a rapid piston (32) having a cross section smaller than the reaction piston (19) and sliding in a sealed manner in a bore (31) of a bushing (30) in bore (200; and a ratio control (27) actuated by a plunger distributor (10) driven by the manual operating member (4). The elastic return member (22) is arranged outside of the primary piston (3) and a transmission element (T) is provided to transmit a return force of the elastic return member (22) to the reaction piston (19).

Abstract: A servobrake (10) including a pneumatic brake booster (12) and a master cylinder (22) with a main piston (20) that slides in a front pressure chamber (24). The main piston (20) has a fixed first rear end (46) acted on by a pneumatic piston (16) of the booster (12) and a moving second rear end (48) acted on by a feeler (18) of the booster (12) that is a coaxial with the piston (16) and acts upon a reaction ram (52) to communicate pressure forces in a front pressure chamber (24) of the master cylinder to the second end (48). A hydraulic isolation valve shutter (58), independent of the internal piston (50) of the ram (52), is activated when the input force of the booster (12) exceeds a given rate threshold so that the braking force is not reduced.

Abstract: A device, for the translation of a displacement of an actuator, in particular for an injection valve, essentially comprises two counter-displaceable pistons, coupled together by means of a translational chamber in a play-free manner. The translation chamber is filled with a translation medium and is connected to an equalization chamber by means of a sealing gap. The sealing gap only equalizes pressure differences between the translation chamber and the equalization chamber which are of long duration. One of the two pistons is pre-tensioned in a starting position by means of an externally arranged spring. A reduction in the dead volume between the pistons is possible as a result of the arrangement of the spring outside the piston. The function of the translation device is thus improved.

Abstract: A braking device comprising a master cylinder (2), a primary piston (3), a manual control member (4), a booster (6) coupled to the manual control member (4) and an emergency assist valve (VA). The emergency assist valve comprising a reaction piston (17) through which there passes a ratio control (T) having a head (26a) situated in a chamber (35) lying between the reaction piston (17) and a bushing (36) located further forward in a bore (18) in the primary piston. The bushing (36) has a bore (37) in which there can slide a rapid piston (38), the rear end (45) of which forms, with the head (26a) of the ratio control, a valve (C). The valve (C) is capable of closing the inlet to a passage (39) in the rapid piston against the action of a spring (41). The braking device comprises a means (26, 27, 30) for preventing a sharp retreat of the reaction piston (17) when the manual control member (4) is released after slow braking.

Abstract: A hydraulic brake booster has a housing with a stepped bore for retaining a cylindrical piston and a control bore for retaining a control valve. The cylindrical piston defines, with the stepped bore, an output chamber, a relief chamber and a power chamber; and includes a second stepped bore for a reaction piston. The reaction piston includes an axial bore, receiving a plunger defining an actuation chamber and a poppet valve. The input force initially moves the plunger and poppet valve to interrupt communication between the actuation and relief chambers; and thereafter moves the plunger to pressurize fluid in the actuation chamber, creating an input signal. The input signal activates the control valve; generating a regulated pressurized fluid, supplied directly to a second set of wheel brakes and acts on the cylindrical piston, to pressurize operational fluid supplied to a first set of wheel brakes.

Abstract: A pneumatic servomotor for an assisted braking of a motor vehicle having a unidirectional clutch device (56). The clutch device (56) has a coaxial sleeve (58) that slides on a plunger (46), and a substantially ring-shaped key (60) that is arranged with a given clearance around the sleeve (58) and driven by a moving piston (22). When an input force is applied at a determined speed onto a control rod (38) that is integral with the plunger (46), the key (60) rocks and locks a finger (52) that biases the piston (22) with respect to the sleeve (58) in an axial position. The key (60) includes a peg (78) for axial indexing of the locking position of the sleeve (58).

Abstract: A hydraulic brake booster (12) having a housing (100,200) with a first bore (102) separated from a second bore (104). The first bore (102) retains a power piston (50) and the second bore (104) retains a control valve (60). The first bore (102) is connected by a passage (112) to the second bore (104) that is connected to a source of pressurized supply fluid (24). In responsive to a desired braking force being applied to the input member (30,30′), the lever arrangement (80) moves the control valve (60) to allow controlled pressurized supply fluid to be communicated from the second bore (104) by way of passage (12) to the first bore (102).

Abstract: A vehicle hydraulic brake apparatus includes a brake member, a master cylinder generating brake hydraulic pressure, and a master piston movable in response to operation of the brake member. A closed chamber is defined by the master piston and a power piston is disposed behind the master piston. A power chamber is defined by the power piston rearwardly of the power piston. An auxiliary hydraulic pressure source generates power hydraulic pressure and a pressure regulating device regulates the output power hydraulic pressure and feeds it to the power chamber. A reaction force member is disposed in a front end portion of the power piston and is exposed towards the closed chamber. A retaining device maintains the reaction force member exposed towards the closed chamber, with the rearward reaction force of the master piston being transmitted to a front end portion of the power piston while bypassing the reaction force member.

Abstract: A hydraulic-pressure counter-force mechanism 37 which produces a counter force when a brake booster is operated is made up of an input-side member 38 slidable disposed within a valve body 3, a second constant-pressure chamber 39 formed on the rear side of the input-side member and into which a pressure is introduced from a constant pressure chamber A, and a second constant-pressure chamber 39 formed on the front side of the input-side member and into which a pressure is introduced from a variable pressure chamber B. The counter force from the hydraulic-pressure counter-force mechanism 37 is reduced by an orifice passage 43 as counter-force reducing means in rapid operation for brake.

Abstract: In a braking pressure intensifying master cylinder of the present invention, as an input shaft 53 travels forwards in a braking maneuver, a control valve 54 is actuated to develop fluid pressure according to the input in a reaction chamber 38 and a pressurized chamber 35. A stepped spool 45 as a part of the control valve 54 travels such that force produced by the fluid pressure and spring force of a spring 51 are balanced, whereby the stepped spool 45 can function as a travel simulator. By changing the pressure receiving areas of the stepped spool 45 and/or changing the spring force of the spring 51, the travel characteristic of the input shaft 53 as the input side can be freely changed independently from the output side, without influence on MCY pressure as the output side of the braking pressure intensifying MCY 1. In addition, the master cylinder pressure can be intensified when necessary with a simple structure.

Abstract: A hydraulic brake device for a vehicle includes a master cylinder having a master piston and an auxiliary piston for assisting the actuation of the master piston. The vehicle hydraulic brake device also includes a first valve mechanism for hydraulically closing a first pressure transmitting chamber when the actuation of the master piston is assisted by an assisting device, a second valve mechanism for hydraulically closing a second pressure transmitting chamber after the pressure in the first pressure transmitting chamber reaches a predetermined value, and for hydraulically connecting the second pressure transmitting chamber with the first pressure transmitting chamber when the master piston is not actuated by the assisting device.

Abstract: A hydraulic-reaction master cylinder (2) having a working chamber (12) in which slides a hollow main piston (13) with a bore (130) therein which retains a reaction piston (14) to define a reaction chamber (15). The reaction chamber (15) has an annular shape and communicates with the working chamber (12) through at least one non-return valve (22) or an axial passage (23). The axial passage (23) is closed off selectively an axial stub (141) that extends from the reaction piston (14).

Abstract: A fluid pressure boosting device of the present invention performs jumping action at a higher servo ratio until fluid pressure in a power chamber (25) reaches a first predetermined value and a rear end (20e) of a reaction piston (20)comes in contact with a step of an input shaft (18). Since a switching valve is set in a first position I until the fluid pressure in the power chamber (25) reaches a second predetermined pressure, a reaction chamber (41) is connected to the reservoir (33) so as to be at atmospheric pressure. In this state, the normal brake control at a lower servo ratio is performed. As the fluid pressure in the power chamber (25) reaches a second predetermined value, the switching valve is set in a second position II by the fluid pressure so that the pressurized fluid in the power chamber is introduced into the reaction chamber (41). The fluid pressure in the reaction chamber 41 acts on the step between the reaction piston (20) and the input shaft (18) so that the servo ratio becomes higher.

Abstract: The invention relates to a master cylinder with hydraulic reaction for a pneumatic brake booster, comprising a main piston (12) receiving a boost force, and a reaction piston (3), mounted so that it can slide in a reaction chamber (4) of the main piston and receiving an actuating force. The master cylinder of the invention also comprises a seat support (7) against which the reaction piston (3) can press and which is mounted so that it can slide towards a low-pressure chamber, the reaction piston (3) and this seat support in combination constituting a stepped assembly in the reaction chamber (3) capable of receiving, from the pressure in the reaction chamber (3), a force which combines with the braking effort after a sharp application of the brakes.

Abstract: The invention relates to a master cylinder with hydraulic reaction, comprising a working chamber (12) in which there slides a hollow main piston (13) inside which a reaction piston (14) delimits a reaction chamber (15) which communicates with the working chamber (12) through at least one non-return valve (22). According to the invention, the non-return valve (22) is installed on a floating stepped piston (23) using the kind of assembly used in brake pressure regulators, so as to limit the reaction force applied to the reaction piston (15).

Abstract: A master cylinder with hydraulic reaction. The master cylinder having a housing with a working chamber (12) therein in which slides a hollow main piston (3). The main piston (3) has a bore (130) for retaining a reaction piston (14) to define a reaction chamber (15). The reaction chamber (15) is connected to the working chamber (12) through a non-return valve (22) and a restriction (17). The non-return valve (22) and restriction (17) are mounted to independently move with respect to the main piston (3) to avoid a defect with a rise in pressure in the reaction chamber (15) when brake fluid retained in the working chamber has an excessively high viscosity.

Abstract: A braking device for a motor vehicle comprises a master cylinder (200) and a pneumatic booster (100). The pneumatic booster includes a rigid casing (10) divided by at least one moving partition (16) into at least two chambers (12, 14). A main hydraulic piston (30) of the master cylinder (200) includes a reaction piston (34) which slides in a hollow moving cylinder (32). The reaction piston includes a normally open two-way valve (94, 95) which can interrupt communication between an interior (V) of the master cylinder and the interior (35) of the moving cylinder (32); a first part (50) which abuts against the moving cylinder (32), in the rest position; and a second part (52) which abuts against the first part (50), in the rest position. A stepped third piston (82) slides inside a stepped bore (84, 85) of the moving cylinder (32) and abuts against the first part (50), in the rest position.

Abstract: A master cylinder with a main piston (12) located in a main bore (110) of a body (11). A reaction arrangement including a reaction piston (3) which slides in a secondary bore (120) in the main piston (12) for providing a reaction to a pneumatic booster. The reaction arrangement includes a shut-off seat (31) associated with the reaction piston (3), an annular wall (4) located in the secondary bore (120) at a distance from the reaction piston (3), a ratio change-piston (5) located in a leaktight sliding in a central passage of the annular wall (4) and a floating piston (6) mounted in a leaktight sliding within the ratio change piston (5) for providing the reaction piston (3) with a reaction force when an actuation force is applied to quickly to the reaction piston (3).

Abstract: A master cylinder having a main piston (12) located in a main bore (110) of a body (11) to define a working chamber (13), a reaction piston (3) located in a stepped bore (120) of the main piston (12) to define a reaction chamber (4) with components to providing a hydraulic reaction to a pneumatic booster. The main piston (12) slides in the main bore (110) in response to a boost force to develop an actuation force while the reaction piston (3) slides in the stepped bore (120) in response as a function of the actuation force. A first shut-off seat (41) is located on a front face of the reaction piston (3) is located in the reaction chamber (4) while a second shut-off seat (42) located in the reaction chamber (4) is mounted on a seat support (7) carried by the main piston (12). A first spring (51) urges the reaction piston (3) in a direction most likely to move the first shut-off seat (41) away from the second shut-off seat (42).

Abstract: A boosted braking system for a motor vehicle having a master cylinder (200) equipped with a main hydraulic piston (30) for causing an increase in pressure (P.sub.1) of brake fluid and a pneumatic booster (22) which is controlled by the application of an input force (F.sub.2) to a control rod (26). The control rod (26) being integral with a plunger (28) which controls the opening of a three-way valve (24). The booster (22) having a rigid casing (10) which is divided in a leaktight fashion into at least first (12) and second (14) chambers by at least one moving partition (16). The moving partition (16) being acted on by a difference in pressure between the first (12) and second (14) chamber on the opening of the three-way valve (24). The moving partition (16) driving a pneumatic piston (22) which carries the three-way valve (24) and contributing to at least in transmitting a boost force (F.sub.1) to the main hydraulic piston (30) of the master cylinder (200).

Abstract: A boosted braking device for a motor vehicle having a master cylinder (200) and a pneumatic booster (100). The master cylinder (200) is equipped with a primary piston (30) which receives an actuating force to increase pressure in a primary hydraulic circuit (I) which increases an increase in pressure in a secondary hydraulic circuit (II) and a secondary piston (31) which is subjected to the hydraulic pressure in the primary circuit (I). The pneumatic booster (100) is controlled by the application of an input force through which an actuation force is applied to the primary piston (30). The primary piston (30) has a hollow cylinder (200) the interior of which is in communication with the primary hydraulic circuit (I). A reaction piston (34) which slides in a leaktigth fashion inside of the hollow cylinder (200) urged toward the master cylinder by a first elastic force provided by a first elastic member (46).

Abstract: A boosted braking device for a motor vehicle having a master cylinder (200) and a pneumatic booster (100) operated by applying an input force to an operating rod (26). The booster (100) has a rigid casing (10) which is divided by a partition (16) into at least first (12) and second (14) leaktight chambers. The partition (16) is acted upon via a difference in pressure between the first (12) and second (14) chambers on the opening of a three-way valve (24) to allow pressurized fluid to be communicated to the second chamber (14). A main hydraulic piston (30) which is located in the master cylinder (200) has a hollow cylinder (32) which is in communication with an interior volume (V) of the master cylinder (200). A secondary hydraulic piston (34) slides in a leaktight fashion inside of the hollow cylinder (32).

Abstract: A brake system for use in connection with a vehicle including a hydraulic internally boosted master cylinder, a hydraulic pump, and hydraulic brakes wherein the master cylinder controls hydraulic fluid pressure to the brakes and has a primary or sensing piston, a modulator stem, and a secondary pistons, with the sensing piston responsive to a mechanical input force to urge the secondary piston forwards increasing the hydraulic fluid pressure applied to the brakes. In a second embodiment, the internally boosted master cylinder further includes a tertiary piston movable by hydraulic pressure between retracted and extended positions and biased toward the retracted position by a tertiary piston return spring. The tertiary piston controls hydraulic pressure applied to one or more brakes independent of the brakes controlled by the secondary piston.

Abstract: A brake device having a pneumatic brake booster and a master cylinder. The master cylinder operates in response to a combined actuation force derived from a boost force and an input force. The input force is applied to a control rod for opening a valve to develop a pressure differential across a partition. The pressure differential acts on the partition to develop the boost force which is transmitted through a first hydraulic piston retained in the master cylinder. A movable pneumatic piston which carries the control rod is connected to the hydraulic piston and after an initial travel during which the valve is opened acts directly on the hydraulic piston to provide a portion of said actuation force. The input of the pneumatic piston to the hydraulic piston provides a way to operate a master cylinder in response to an input force in the event of a failure of a hydraulic circuit connected to the master cylinder.

Abstract: This boosted brake device comprises a pneumatic brake booster (1) associated with a master cylinder (2), the booster operating according to a hydraulic reaction principle and comprising a movable pneumatic piston (5) carrying a control valve (7) actuated by a rod (8), as well as a partition (4) which can move under the effect of a pressure difference and which develops a boost force.The movable wall (4) is mounted slidingly with respect to the pneumatic piston (5) in order to act early on the master cylinder.The device of the invention allows greater braking for small values of the travel of the control rod.

Abstract: A hydraulic booster for slip-controlled brake systems, including a booster piston (1) arranged in a booster housing (11) and confining a booster chamber (4). A braking pressure control valve is provided whose control part (12) is actuatable by a lever mechanism (13) as a function of the piston of the control part (12). An actuating piston (2) is displaceably guided in the booster piston (1) and is positioned by way of a push rod which cooperates with the lever mechanism (13). To provide a hydraulic booster to realize boosting factors of any desired size, both of constructional and strength-minimizing nature, an annular surface (24) is formed the stepped actuating piston (2), on the side of the push rod (22) and is larger than the total area of any opposing annular surfaces, subject to the booster chamber pressure to create a net force acting to oppose the push rod force and allow setting of the boosting factor by adjustment of the area of the annular surface.