Abstract: An arrangement for controlling the supply of pressurized hydraulic fluid from a master cylinder and from a pressure source into hydraulic circuits leading to wheel brake actuating cylinders includes a valve device including a control piston acted upon by a spring-loaded auxiliary piston in one direction and by the pressure in a return conduit in the opposite direction. Upon brake pedal depression, hydraulic fluid pressure from the pressure source acts on the auxiliary piston in opposition to the spring force so that the auxiliary piston ceases to act on the control piston. Then, as hydraulic fluid is discharged from the brake actuating cylinders during antiskid control action, pressure builds up in the return conduit and propagates to the control piston to move the same into its open position in which it admits pressurized fluid from the pressure source to check valves which are acted upon in opposition to their opening by the tandem master cylinder pressures.

Abstract: A master cylinder is provided on the cylinder body with a reservoir-receiving mouth formed near the border of the section of of a large diameter and the section of a small diameter of a stepped bore, a through hole being formed between the bottom surface of the reservoir-receiving mouth and the first pressure chamber, a compensation hole being formed between the bottom surface of the reservoir-receiving mouth and the second pressure chamber, a valve seat fitted in and fixed to the reservoir-receiving mouth and having an internal hole formed therein, a check valve provided within the reservoir-receiving mouth between the bottom surface of the reservoir-receiving mouth and the valve seat with the valve element being pressed against a resilient member fixed to the valve seat by means of a spring, a projecting member protruding into the first pressure chamber through the through hole provided for the valve element coaxially with the valve element so that the valve element is titlted to form a passage between the

Abstract: Quick assemblable master-cylinder and an assistance servo assembly. According to the invention, the master-cylinder (11) includes several lugs (12) while the end wall of the servo (14) is provided with a cut out (15a, 16a) similar in shape to the profile of a transverse section of the master-cylinder passing through said lugs.

Abstract: An apparatus for controlling braking liquid pressure produces a proportionate reduction in an input liquid pressure supplied from a master cylinder before it is output to a rear wheel cylinder. The apparatus includes a body which is formed of a single member and which is formed with a bore in which a plunger slides. An annular retainer having an inner diameter less than that of the bore is fitted into the bore at its end nearer the master cylinder. One end of the plunger extends through the annular retainer.

Abstract: A brake apparatus 10 having a master cylinder 16 with a flange 24 connected to a first shell 56 of a booster 18 and a stationary firewall 71 of a vehicle. A first wall 70 located between the flange 24 and first shell is connected to a piston 38 in the master cylinder 14. A second wall 144 located between the first shell 56, flange 24 and a second shell 121 is linked to the first wall 70 by a plurality of bolts 180 that pass through the flange 24. A valve 102 in response to an input controls the development of a pressure differential across the first and second walls 70 and 144. This pressure differential creates a force such that the first wall 70 pushes piston 38 while the second wall 144 pulls the first wall 70 to pressurize fluid in the master cylinder 16. Since the flange 24 fixes the master cylinder 16 to a stationary firewall 71, measurable axial deflection is eliminated and the entire input is used to operate valve 102 and effect a brake application.

Abstract: A master cylinder includes a housing (18) with a pair of pistons (60, 64) operable to pressurize a pair of pressure chambers (66, 72). One (64) of the pair of pistons includes means (76, 80) to control communication from a reservoir (34) to both pair of pressure chambers (66, 72).

Abstract: A master cylinder includes a housing (12) with a bore (14) receiving a pair of pistons (32, 34). A bearing (50) extends from the housing (12) to one of the pistons (32) to define a passage (65) communicating fluid to a pressure chamber (40). The bearing (50), the passage (65) and the pressure chamber (40) extend outwardly of the housing bore (14) to permit the length of the housing to be reduced.

Abstract: A reservoir assembly for a master cylinder includes a housing with a surface adapted to interface with the reservoir assembly. The reservoir assembly comprises a first part made from a lightweight plastic material and a second part made from a metallic material. The second part is adapted to fit on the surface while attachment of the reservoir assembly to the housing is provided for by the second part.

Abstract: In a tandem type brake master cylinder having a body formed with coaxial large and small cylinder bores, a first piston member having a large land sliding in the large bore and a first small land sliding in the small bore, a second piston member having second and third small lands sliding in the small bore, a first chamber defined between the large land and the first small land, a second chamber defined between the first and the second small lands, a third chamber defined between the third small land and a closed end of the small bore, a first spring biasing the first and second piston members apart, a second spring biasing the second piston member away from the closed end of the small bore, first and second outlets opening from the second and third chambers respectively, and a means to allow fluid to pass from the first chamber to the second chamber but not back, a means is provided to prevent the first piston member and the second piston member from becoming separated by a distance greater than a certain pr

Abstract: The disclosure describes a new type of pressure cylinder to provide clamping force while fabricating deep drawn metal parts. The piston is a hollow cylinder connected to the clamping pad. The drawing tools are connected to the draw ram by a rod passing through the hollow piston. This arrangement provides a smaller overall press height and an axisymmetric clamping force. In addition, the symmetry of the parts described means that the wear parts can be reversed to double their useful lives.

Abstract: A system for resiliently supporting a load at a reference height includes a hydraulic cylinder for resiliently supporting a load about a reference height and an accumulator which cooperates with the cylinder for flowing hydraulic fluid therebetween in response to varying loads imposed on the cylinder. A valve is provided for dampening the rate of fluid flowing between the cylinder and the accumulator and a metering valve coacts with the cylinder for adjusting the reference height about which the load is supported.

Abstract: A two-stage, hydro-pneumatic actuator suitable for use as a railway vehicle brake. The hydraulic cylinder comprises a large diameter bore in which a low- and a high-pressure piston operate jointly during a first stage of operation to effect a high volumetric displacement of hydraulic fluid via a small diameter bore in order to take up the clearance between the brake shoes and wheel. As the brake shoes contact the wheel, the high-pressure piston enters the small bore to interrupt further displacement of hydraulic fluid from the large bore. The force of the high-pressure piston alone during this second stage of operation produces the required brake forces with a high multiplication factor. Make-up fluid is drawn into a chamber on the backside of the low-pressure piston during a brake application stroke an amount corresponding to the over-travel of the high-pressure piston and is subsequently discharged into the hydraulic cylinder during retraction of the brakes to compensate for brake shoe wear.

Abstract: A hydraulic jack having a piston and a cylinder in which the piston has at its head a cavity the dimensions of the cavity and the constructional materials of the cylinder and the piston being selected so that hydraulic pressure applied within the cylinder acts to deform the cylinder wall and the parts of the piston defining the cavity in such a manner that, over the normal rate of operating pressures of the jack the clearance between the piston and the cylinder remains within the capacity of the sealing means arranged between the piston and the cylinder to provide an effective seal.

Abstract: A brake booster includes a body having a central wall portion on which a, doughnut-shaped reinforcement plate is securely mounted, and bolts mounted on the reinforcement plate for fastening a master cylinder to the central wall portion. The reinforcement plate has an annular ridge extending along an inner peripheral edge thereof and projecting against the reinforcement plate. The master cylinder includes a flange mounted on the body and having an inner peripheral portion held against the central wall portion of the body in axial alignment with the annular ridge, and an outer peripheral portion spaced from the central wall portion by a distance such that the outer peripheral portion of the flange will not be forced into contact with the central wall portion when the master cylinder is actuated for braking action. Therefore, no localized forces are applied by the outer peripheral portion of the flange to the central wall portion of the body.

Abstract: A braking-force booster which contains a pressure source, a pedal operated control valve and at least one main brake cylinder; a piston which creates the brake pressure, is exposed to the pressure created in the main brake cylinder by means of the control valve, wherein the control valve, dependent on the pedal displacement, interrupts a connecting channel between the main brake cylinder and a pressureless connection and temporarily creates a second connecting channel between the pressure source and the main brake cylinder. The pedal operated control valve contains a plunger movable by the pedal which extend into the main brake cylinder, and the first connecting channel is integrated into the main brake cylinder piston. The first plunger has a valve closing member for shutting off this connecting channel during the corresponding approach.

Abstract: A compact rotary power cylinder including a pair of pistons fitted in a cylinder housing, separating the housing into a first chamber and a pair of second chambers, so as to be reciprocally movable when a pressure impact is supplied selectively to the first and second chambers, and a torque stem provided through the housing perpendicularly to the reciprocal motion of the pistons so as to be rotatable in response to the reciprocal motion, in which a pair of connecting members are provided between the stem and the pistons so as to be movable in a radial direction of the stem.A relatively large breakaway torque is achieved with such structure.

Abstract: A compressible bellows surrounds a piston rod of the hydraulic cylinder of a hydraulic elevator. The lower end of the bellows surrounds a liquid receiving recess in the gland box of the cylinder and, when a sealing ring on the piston rod closes and compresses the bellows, the leaked hydraulic fluid is discharged from the recess, via a ball check valve, and a return tube to a sump.

Abstract: A multi-axis robot wrist assembly having three hydraulically operated rotary actuators which are mechanically connected in series such that the output of each actuator drivingly positions the body of the succeeding actuator located outboard thereof. The hydraulic connection to any wrist actuator, except the innermost actuator, includes a series-connection of (a) internal passage(s) through actuator(s) which are located inboard of the actuator in question and (b) external line(s) between the actuator in question and actuator(s) located inboard thereof. By connecting all but the innermost wrist actuator through hydraulic paths which are at least partially internal to actuators positioned inwardly thereof, the overall envelop of the wrist assembly is reduced.

Abstract: A dual power brake booster assembly in which the hydraulic boost section is initially operated, the vacuum booster section is then operated to runout while the hydraulic section maintains a hydraulic boosted force level, the hydraulic section is then further operated to further increase the hydraulic boosted force as the vacuum booster section maintains the vacuum boosted force level attained by it at runout, and additional master cylinder actuation by additional manual force. The invention also includes the method of generating brake actuating pressure. The brake booster assembly may be operated only to the extent necessary to produce the desired amount of master cylinder actuation. The booster assembly will operate when the power source for one section is diminished or not available. It is also operable manually when pressure from neither power source is available.

Abstract: A hydraulic ram for use in thrust-jacking of tunnel linings comprises a cylindrical outer member, a cylindrical inner member reciprocable within the outer member, and an extension member reciprocable within the inner member. A two-part clamping ring is provided for releasably locking the extension member to the inner member. An auxiliary drive is provided for retracting the extension member rapidly within the inner member. The auxiliary drive may be a mechanical spindle drive, or a hydraulic drive having an auxiliary piston reciprocable within an axial bore formed in the extension member. The clamping ring comprises spring means for urging the parts of the clamping ring in to the closed position, and piston-and-cylinder means for urging the parts of the clamping ring apart, against the biasing force of the spring means, to open the clamping ring.