Abstract: A pneumatic actuator includes a tubular body made of a rubber-like elastic material and a braided structure made of organic or inorganic high-tensile-strength fibers reinforcing an outside of the tubular body. Closure members sealingly close ends of the tubular body; at least one of the closure members has a fluid connecting passage. The tubular body deforms to expand its diameter when pressurized fluid is introduced through the connecting passage to cause contractive force in the longitudinal direction. Contraction-detecting strain gauges at one closure member provide signals corresponding to the contractive force of the actuator.

Abstract: In a piston-cylinder assembly for hydraulic brake systems of automotive vehicles, the piston is at least partially composed of ceramics. A hydraulic seal is interposed between the piston and the cylinder. To simplify the assembly while allowing comparatively great tolerances, the seal is fitted at the end of the piston that is adapted to be mounted close to a pressure chamber within the system. The seal is provided with radially-extending projections which cause the piston to spring back by a roll-back effect.

Abstract: A method of packing elongated porous bodies moved between zones of different pressure, wherein the porous body (T) reciprocates through a pressurized packing agent (M). The packing agent is thixotropic and is supplied continuously to the porous cable (T) under a pressure exceeding the pressure in a higher pressure zone (P.sub.1) while the porous body (T) is impregnated with a thixotropic packing agent (M) such that the cross-section of the cable, throughout its entire length, is filled with packing agent (M). A hydraulic cylinder-type actuator utilizes a porous cable power transmission element packed in a chamber (7) filled with viscoelastoplastic material and communicated with means designed to develop in said chamber a pressure exceeding the pressure of the actuator working fluid.

Abstract: A master cylinder of the center feed type including a cylinder defining an axially extending pressure chamber and including a reservoir port proximate the front end of the cylinder for connection with a fluid reservoir; a piston slidably positioned in the cylinder and adapted for coaction with a piston rod extending into the rear end of the cylinder; a valve assembly in the pressure chamber including a valving member proximate the reservoir port and a valve stem secured to the valving member and extending axially rearwardly in the pressure chamber; and a retainer on the front end of the piston.

Abstract: A hydraulic flow divider has first and second (147, 148) flow control valves each dividing its inflow into two flows. The constant orifice first flow control valve (147) divides flow to outlets (151) and (153). Flow from outlet (151) is then divided by the second valve (148). One of the output flows of the second valve is generated by a constant orifice and directed to a power steering cylinder. Any secondary output from the second valve is generated by a pressure relief valve (152), joins flow from outlet (153), and passes to a hydraulic lift cylinder. The arrangement secures a significant flow rate for lift cylinder operation at low pump drive engine speeds at which pump output flow is low.

Abstract: A hydraulic actuator assembly of the type including a hydraulic system comprising a master cylinder, a slave cylinder, and a conduit interconnecting the master and slave cylinder. One-way valve means are provided, either mounted on the master cylinder or interposed in the conduit interconnecting the master and slave cylinders, and these valve means function to block communication between the system and the associated reservoir when the system if pressurized but allow flow of replenishing fluid from the reservoir into the system when the system is depressurized to compensate for system losses and wear in the associated vehicular mechanism. The valve further includes a manual override member in the form of a plunger which is manually depressed and which moves a valving member of the valve to a position in which it establishes communication between the reservoir port and the system port so that fluid may be moved from the system and into the reservoir even when the system is pressurized.

Abstract: A tandem master cylinder has a housing containing two pressure chambers for connection to separate braking circuits. A pressure piston component forms pistons movable in the pressure chambers to supply fluid under pressure to the circuits. A balance piston has opposed surfaces subject to the pressures respectively in the chambers and is movable, in response to a pressure difference between the chambers, to reduce the pressure difference. Control valves operate in response to brake actuating movement of the piston component normally to isolate the chambers from a fluid supply reservoir, and a disabling device disables the respective control valves individually to prevent pressurization of one of the chambers when actuation of one brake only is required.

Abstract: A bellows assembly is provided in which a retainer member is formed as an aluminum extrusion with two uniformly spaced recesses formed therein. A bellows is provided with two uniformly spaced attachment members which coact with the spaced recesses to provide a uniforma bellows profile for its entire length. Accordion pleat members are provided to attach the ends of the bellows to the ends of the retainer member.

Abstract: In a reciprocating piston engine, the piston has a top ring and a second ring received in respective ring grooves. The top ring has two end surfaces defining therebetween a gap the open area of which on the side of the combustion chamber, when the top ring abuts against the upper surface of the ring groove, is smaller than an open area of the gap facing a second land clearance when the top ring seats on the lower surface of the ring groove. As the top ring seats on the lower surface of the ring groove during the power stroke when the engine is operated at a high-speed, high-loaded condition, the greater open area of the gap rapidly introduces the combustion pressure into the second land clearance to thereby reduce oil consumption. When the engine works at a low-speed, low-loaded condition, the top ring abuts against the upper surface of the ring groove during the intake and compression strokes, where the smaller open area of the gap reduces the flow of oil from the crankcase to the combustion chamber.

Abstract: Airlift apparatus used in conjunction with a weight lifting machine that utilizes a stack of weighs. It assists the weight lifter when fatigue occurs. Its construction is of plastic, consisting of a cylinder and a piston. The piston is moved by differences in air pressure which is induced by a vacuum pump located at the bottom of the cylinder. A cable and a series of pulleys connect the weight stack to the piston. The system is activated by the lifter at any stage of the lift by a foot or hand operated switch. When not in use the Airlift does not adversely affect the normal operations of the weight lifting machine.

Abstract: Improved control of a hyrostatic drive machine at very small speeds of rotation. The rotation speed control signal in the creep rotation speed region is modified in dependence upon the actual value of the rotation angle and possibly the efficiency characteristic diagram so as to produce a regulated constant torque.

Abstract: A brake booster has a first booster cylinder and a booster piston disposed in it for displacing a master cylinder piston to pressurize a brake circuit. A tappet displaces the first booster piston directly if boost fluid pressure is inadequate. A second booster piston in a parallel booster cylinder drives a pump piston which also pressurizes the brake circuit. The second booster piston and the pump piston have hydraulically effective surface areas which are matched to one another so as to have a larger boosting ratio than the first booster piston and master cylinder piston. Forward displacement of the second booster piston causes a bent arm to contact and push the first booster piston forward. If the boost pressure supply apparatus fails, then only the first booster piston and the master cylinder piston are displaced by the brake pedal; brake pedal travel increases considerably.

Abstract: A two-part, low compression height, open-ended hollow skirt-type piston for internal combustion engines has a piston pin creating an articulated connection of the separate skirt and head parts. Guide portions (5) protruding axially in the direction of the piston axis provide lateral guidance and support of the piston head (1) in the piston-pin-axis direction. Each of the guide portions forms a gap with the nearby gudgeon pin boss (3). The gaps receive opposite parallel flat surfaces (4) of the skirt (2). The overhanging guide portions (5) have partly circular recesses permitting assembly of head and skirt with the gudgeon pin.

Abstract: A lightweight counterrotatable propeller system driven by a rotatable shaft is disclosed. The system includes first and second counterrotatable propellers, each propeller including a plurality of blades mounted on first and second hubs, respectively. Each blade is attached to the hub by means of a ball screw which converts centrifugal force on each of the rotating propeller blades into a pitch changing force. Gearing means for operatively connecting the shaft with each propeller are located between the propellers with a carrying member for one of the propellers forming an outer wall which radially bounds the gearing means. Additionally, non-rotating actuating means for changing propeller pitch are operatively connected to the blades of each of said first and second propellers through first and second thrust bearings, respectively.

Abstract: Apparatus and method for maintaining viscous liquid sealing substances such a grease adjacent and in contact with seals utilized in pneumatic cylinder-and-piston actuators for oil and gas well swabs, the structure including a piston member which is slideable on the piston rod and which includes an external O-ring for sealing engagement between the cylinders and the piston member and an internal O-ring which is in sealing engagement between the piston member and the piston rod. The piston member is resiliently urged by a compression spring towards the actuating piston and the viscous liquid is trapped between the actuating piston and the slideable piston member. A further like slideable piston member may also disposed on an extension of the piston rod on the opposite side of the actuating piston which is also urged towards the actuating piston. Viscous liquid is trapped between the latter slideable piston member and the actuating piston.

Abstract: An improved energy-conserving servoactuator has at least one valve operatively associated with a double-acting fluid-powered actuator. When a load is applied to the actuator, the pressure in one actuator chamber will be greater than in the other. If the load is "opposing" with respect to the desired direction of actuator movement, fluid is supplied to the higher pressure chamber and is permitted to flow from the lower pressure chamber. However, if the load is "aiding" with respect to the desired direction of actuator movement, fluid in the higher pressure chamber is permitted to flow into the lower pressure chamber without drawing fresh fluid from the source.

Abstract: The invention relates to a linear motor with a cylinder (5) containing a piston linked to a piston rod (8) projecting from either of the end faces of the cylinder (5). To secure the piston rod against torsion and rotation, a guide comprising at least two guide ribs (22, 22') arranged on the circumference of the cylinder (5) is provided, these ribs being arranged at a distance from each other and extending in the axial direction of the cylinder (5). A slide (19) seated on the outside of the cylinder (5) and guided on the guide ribs (22, 22') while at least partially encompassing them is fixed to the piston rod (8).

Abstract: A safety system connecting a pressure medium source, user, and a pressure reservoir (accumulator) has a pressure port, a supply container port, a reservoir port, a three-way valve and a pressure relief valve. The pressure relief valve is attached to the pressure port and to the three-way valve. The valve member of the three-way valve in a first position connects the pressure port with the reservoir port. In a second position, the valve member connects the reservoir port with the supply container port. To avoid the disadvantages of a three-way valve with negative overlap, an arrester check or anti-return valve is inserted between the pressure port and the reservoir port closing toward the reservoir port. The three-way valve has a positive overlap.

Abstract: A regulator arrangement (14) for a servo system (10) having a first stage valve spool piston (44) for developing a primary operational fluid (P.sub.c) and a second stage valve spool piston (70) for developing secondary operational fluid P.sub.cr having a constant fluid pressure. A control valve (109) selectively connects a first chamber (100) of a cylinder housing bore to either the primary operational fluid pressure P.sub.c or a reference fluid pressure P.sub.B to develop a fluid pressure P.sub.x in first chamber (100) while a second chamber (102) is connected to the secondary operational fluid (P.sub.cr). A load piston (96) responds to a pressure differential (P.sub.x -P.sub.cr) by moving to either expand or contract the second chamber (102) and produce a fluid pressure (P.sub.crx) in the secondary operational fluid. The fluid pressure P.sub.crx is communicated to the second valve piston (70) to correspondingly allow either additional primary fluid (P.sub.

Abstract: A joint for connecting a driving means to a driven means for reciprocating movement wherein a confined deformable, non-compressible material is in contact with a surface area of the driving means and with a surface area of the driven means and when a force is applied to the driving means to move the driving means toward the driven means, the deformable, non-compressible material deforms to compensate for any misalignment between the driving means and the driven means until is reaches it non-compressible state so that a uniform force is then transmitted across the surface area of the driven means in one direction to move the driven means.