Abstract: In a vacuum suspended type servo device, there is arranged a power ratio adjusting means for adjusting the power multiplying characteristic of the servo device to a desired degree.

Abstract: A reciprocatory air motor has a main plunger valve the position of which controls the flow of air to opposite sides of a main motor piston. Positioning of the plunger valve is itself controlled by a pair of cushion pistons carried on the piston rod of the motor. A space between the cushion pistons is used for the compression of air to effect absorption of the kinetic energy of the moving parts of the motor at opposite ends of the stroke.

Abstract: A cylinder for a valve actuator wherein the cylinder body has lugs connectable to and disconnectable from like cylinder head lugs by less than one turn rotation. Resilient seals seal the head to the body when connected, and the connection is releasably lockable.

Abstract: The stop key (60) for the plunger (50) of the valve means (30) of the servomotor (10) is mounted without play in a radial recess of the hub (19) of the working piston (20), the key having a flat body portion and two angularly folded lateral edges, the recess having a constant axial dimension essentially identical to the overall thickness of the key.

Abstract: A power steering apparatus includes a control valve of disc type which controls the delivery to or displacement from a power cylinder of a hydraulic fluid. A pair of mating parts are formed on the input and the output side for integral rotation therewith. A substantially C-shaped spring is engageable with the mating parts, which are maintained in position by the resilience of the spring.

Abstract: A retainer 226 for holding a control valve 656 of a servomotor 42 in a bore 90 of a hub 78. The hub 78 which is attached to a movable wall 56 has first 92 and second 96 passages that connect the bore to first 86 and second 88 chambers in the servomotor 42. The retainer 226 limits the movement of the control valve 656 in the bore 90 to establish a full release position whereby the pressure of the fluid in the first 86 and second 88 chambers equalize. In response to an input force, the control valve 656 moves to an actuation position where fluid under pressure is communicated to the second chamber 88 to create a pressure differential across the movable wall 56. The pressure differential acts on the movable wall 56 to develop an output force corresponding to the input force. On termination of the input force, the control valve 656 moves to the full release position where the fluid pressure equalization occurs.

Abstract: An assistor for operating a transmission, to be installed between the gearshift lever and the shift lever for actuating the shift jaws of the transmission, comprises a semicylindrical cylinder, a vane type piston adapted to turn slidingly within the cylinder, and a directional control valve for supplying a fluid to chambers defined by the vane of the piston. Operation of the gearshift lever opens the directional control valve to supply the fluid to one of the chambers separated by the piston vane, whereby the piston is turned and its turning output is transmitted from its boss to the shift lever.

Abstract: An actuator system characterized by parallel connected flow regulator valves for controlling the flow of fluid to and from the extend ends of a corresponding number of fluid actuators. Retract orifices in the fluid lines leading to the retract ends of the actuators prevent cavitation of the extend ends of the actuators under an aiding air load pulling the actuators out during extension thereof.

Abstract: In vacuum brake boosters for motor vehicles, the vacuum casing is conventionally made of sheet steel. The vacuum casing is subjected to mechanical and pneumatic forces which have to be absorbed by the casing components. This makes it necessary to construct the casing components so they are strong enough to take these forces. The result of such construction is, however, high costs and high weight. To eliminate these disadvantages, the invention provides a brake booster wherein the vacuum casing includes a pipe therein extending in approximately coaxial of the longitudinal axis of the vacuum casing and connected to the transverse end walls of the vacuum casing, the pipe enclosing the master cylinder push rod, and the movable wall of the brake booster is sealed relative to the pipe and slidable thereon.

Abstract: A piston for a fluid pressure chamber having an arcuate longitudinal axis. Such piston comprises an assemblage of two spherical bodies in side-by-side relationship and interconnected by a universal pivot. Each spherical body carries a circumferential piston ring receiving groove and piston rings are mounted in such grooves to provide a sliding and sealable engagement with the walls of the fluid pressure chamber as the piston moves along the curved longitudinal axis of such chamber.

Abstract: A brake booster comprising a housing which is divided into a vacuum chamber and a working chamber by a movable wall. A tube is disposed in the housing coaxial of the longitudinal axis thereof having its ends fastened to the end walls of the housing. The tube is provided with longitudinal slots in the vacuum chamber which are open remote from the movable wall. Parts of the movable wall project through the slots and are fastened to a valve housing extending into the tube, the valve housing containing a control valve which controls the pressure in the working chamber. This arrangement allows a short overall length of the booster and enables easy assembly thereof with respect to known prior art brake boosters.

Abstract: Vehicle power steering gear with a torsion bar whose stiffness is adjusted by an axially shiftable nut that provides a movable gripping point for one end of the torsion bar whose position determines the pliable length of the bar and the steering effort required to steer the vehicle.

Abstract: An improved trigger valve for a pneumatic nailing machine is disclosed. A communication hole between the main air chamber and the pilot air chamber is made as small as possible. This allows the trigger valve to return in a delayed manner so that the head valve and driver piston operate properly.

Abstract: The invention pertains to vehicle brake actuators of the expansible motor type wherein the actuator includes a cylinder having a piston and piston rod assembly reciprocal therein, a helical spring biases the piston in a braking direction, and a pressurized medium, such as hydraulic fluid, forces the piston in a spring compressing direction. The unique features include a piston drawn from sheet metal wherein the piston rod is pressed thereinto, and the piston seals are retained in position by a wire ring having an interference fit with the piston. Additionally, novelty resides in the use of a retainer formed of wire or of stamped construction having protuberances defined thereon for retaining the cylinder end cap upon the cylinder in a manner to permit ease and safety of assembly, and uniform force distribution.

Abstract: A control device for working cycles of a self-propelled pneumatic boring device with a non-rotatable axially displaceable impact piston controllable by control edges of a control sleeve supported axially non-displaceably but rotatably and at its front end forming a control head with the control edges. The control head engaging in a cylindrical recess at a rear end of the impact piston cooperates with a radial main control opening formed in the impact piston in the vicinity of the recess. The control edges form two different pairs of the control edges, offset peripherally as well as axially such that respectively in one rotated position of the control sleeve only one of the pairs is aligned for cooperation with the main control opening. The impact piston is formed with at least one additional control opening which cooperates with the other pair and has a flow cross-section considerably smaller than that of the main control opening.

Abstract: The servomotor comprises a piston assembly (9) provided with a tubular hub (25) sliding on a valve sleeve (11) provided with a return roller (51) for a flexible elongate member (40) fixed between an end wall (4', 43) of the casing and an arm (47, 48) of the piston assembly normally extending beyond the return roller (51), between the latter and said end wall.

Abstract: A pneumatic valve is disclosed, for controlling the position of a ram in a partly-extended condition. The valve has a combination of rubbing seals and diaphragms, for smooth operation and reliability. A spring-loaded plunger presses the diaphragm against the mouth of a port, to seal off the port. A piston with rubbing seals lifts the plunger from the diaphragm, to open the port. The piston seals rub against plastic, for freedom from water contamination problems, while the diaphragm provides the high integrity seal needed to control the ram position. A particular application of the valve is to the air control of dentist's chair, medical table or medical chair.

Abstract: A cylindrical piston has a part-cylindrical outcut, which is slotted radially and contains a swingable pivot-member of at least part-cylindrical configuration borne in the outcut and pivoting therein under load. The mentioned outcut is formed partially around an axis which is normal to the longitudinal axis of the mentioned piston and extending through the longitudinal axis of the piston. A plurality of preferably part-annullarily formed grooves for the reception of pressure fluid are provided preferably in said pivot-member in order to lubricate bearing portions of said member between two adjacent grooves or recesses to assure a high pressure lubrication from both ends of the respective bearing portion. Efficiency and lifetime of said bearing portion is thereby increased and so is the bearing capability.

Abstract: A hydraulic brake actuator for a wedge type brake includes a tubular structure extending from the brake and housing an extended end of a stem of the wedge of the brake therein. A primary cylinder is mounted on the tubular structure and includes a primary piston mounted for sealed movement therein. The piston has a rod extending from one side thereof into the tubular structure to be operably connected to the extended end of the stem. A spring acts on a second side of the piston and is capable of moving the piston toward a first position within the cylinder for actuation of the brake. Hydraulic fluid can be selectively introduced to the primary cylinder at the first side of the piston to cause movement thereof in opposition to the spring to a second position to prevent actuation of the brake by the spring. An annular space between an interior surface of the tubular structure and an exterior surface of the rod is sealed to prevent the hydraulic fluid from escaping from the cylinder.

Abstract: A slurry pump is provided having a self-flushing piston assembly mounted in a mating cylinder. The piston assembly includes a first piston having a peripheral sealing member and a reciprocating piston rod for driving the first piston for pumping action. A second piston mounted adjacent to the first piston includes a sealing member and forms an enclosed chamber with the first piston. A lost motion coupler connects the pistons together and varies the size of the chamber. On the return stroke of the piston assembly, flushing liquid on the non-slurry side is sucked into the chamber as the chamber expands. On the power stroke, the flushing liquid is forced past the second sealing member to remove slurry particles and prevent wear of the cylinder. The disc on the first piston has sufficient flexibility to allow filling of the chamber and an accumulator is provided to control the back pressure after the chamber has been filled on the return stroke.