Abstract: A handle linkage including two handle arms rotatably secured to each other, while one handle arm is attached to the body of a tool and the other handle arm is attached to an actuatable member of the tool. One or more links connect the actuatable member to the second handle arm allowing for substantially linear movement of the actuatable member into the body of the tool.

Abstract: A piston-cylinder unit for producing and transmitting compressive forces onto adjusting elements which are guided so as to be slidable on a straight line. The piston-cylinder unit includes a push rod mounted so as to be capable of oscillating transversely of the direction of the compressive forces in a unilaterally open skirt-type piston. The push rod is slidingly movable from a centered position into an oscillating position. The centered position is determined by sealing members placed so as to face each other and mounted at an outer periphery of the push rod and an inner rim of the skirt-type piston. The push rod is movable into the skirt-type piston toward a fixed stop arranged in the skirt-type piston. The push rod is movable against the force of a spring element arranged at the bottom of the skirt-type piston.

Abstract: A machine that converts between reciprocating motion of a piston and rotary motion of a shaft. The shaft rotates an integral web that carries a number of lobe wheels spaced evenly about a pitch circle centered on the shaft. The lobe wheels are planetary driven by pinions and a fixed ring gear. The lobe wheels are somewhat star shaped with radially extending lobes which push followers outwardly, then release them inwardly, as the lobe wheels orbit past and below the follower. The follower is connected by a lever and a pair of connecting rods and to the piston.

Abstract: A diaphragm valve for high pressure use has a metal diaphragm which is actuated into and out of direct engagement with a valve seat by an air operator acting through a force multiplying lever assembly. The valve seat is confined by rigid interior and exterior sleeves while the sealing surface is contoured to have a concave configuration corresponding to the contour of the diaphragm in its deflected position. The air operator is provided with a stroke adjustment mechanism that is locked in adjusted position by a member that is generally accessible only when the operator is disconnected from the valve.

Abstract: A fluid pressure operated nailer is provided including a portable housing having a fixed generally longitudinally extending chamber axis, a fluid pressure actuated mechanism mounted in the housing for movement through successive operative cycles. The nailer includes an elongated nail driving element having a nail engaging end, an opposite end and a longitudinal driver axis extending therebetween. A housing nosepiece is provided which includes surfaces defining a leading nail containing space wherein a nail axis of the leading nail is laterally spaced with respect to the fixed chamber axis. The nosepiece includes surfaces defining a nail feed track extending to the leading nail containing space for guiding a releasably interconnected supply of nails engaged therewith along the nail feed track for generally longitudinal movement therefrom.

Abstract: A volumetric pump and method for displacing a predetermined quantity of fluid at a predefined cracking pressure, independent of supply and output pressures. The volumetric pump (30) includes an inlet cracking valve (46), an outlet cracking valve (52), and a plunger (48) for displacing fluid a pumping from a pumping portion (34b) of flexible tubing (34) that extends through the volumetric pump. The pumping portion of the flexible tube fills with liquid when the inlet cracking valve is fully opened and is urged to expand by jaws (236) on pivotally-mounted arms (234). The arms are forced to pivot, as tubing reshaper rollers (160), disposed on the plunger, roll along the inner surface (232) of each arm.

Abstract: An improved connecting rod assembly for a reciprocating internal combustion engine provides essentially simple harmonic linear motion of a piston, thereby eliminating forces and moments caused by non-simple harmonic linear motion of a piston. The connecting rod assembly of the present invention maintains a uniform distance between a crank pin and a piston. Essentially simple harmonic piston motion also increases engine efficiency by reducing the amount of negative work which results from detonation before top dead center. The connecting rod assembly may include a first member rotatably connected to a crankshaft and having two connection points each spaced a distance A/2 from the crankshaft connection, and second and third members having a length C, arranged in a crossing relationship, and connecting respective ones of the connection points of the first member to respective ones of two connection points on a piston, the piston connection points being spaced apart by a distance B.

Abstract: A diaphragm valve for high pressure use has a metal diaphragm which is actuated into and out of direct engagement with a valve seat by an air operator acting through a force multiplying lever assembly. The valve seat is confined by rigid interior and exterior sleeves while the sealing surface is contoured to have a concave configuration corresponding to the contour of the diaphragm in its deflected position. The air operator is provided with a stroke adjustment mechanism that is locked in adjusted position by a member that is generally accessible only when the operator is disconnected from the valve.

Abstract: The actuating device for a master cylinder is constituted by an actating rod (10) acting on a piston (12) of the master cylinder. Elastic centering mechanism (26) are arranged between the actuating rod (10) of the master cylinder and the piston (12) of the master cylinder, and are compressed therebetween.

Abstract: The invention relates to an assembly consisting of a brake booster and of a master cylinder (50), the booster comprising, in a casing (10), at least one movable wall (14, 14') which sealingly divides the interior of the casing (10) into a front chamber (16, 16') and a rear chamber (18, 18'), an input member (24) intended to be connected to a brake pedal and displacing the movable wall (18, 18'), and an output member (28) actuating a piston (46) of the master cylinder (50). According to the invention, a transfer member (40) is arranged between the front face of the casing (10) and the master cylinder (50), this transfer member (40) being actuated by the output member (28) of the booster along a first axis (A--A) and actuating the piston (46) of the master cylinder (50) along a second axis (B--B), and the brake booster, the transfer member (40) and the master cylinder ( 50) form a modular construction.

Abstract: A concentrate supply assembly for a post-mix beverage dispenser includes a plurality of containers for concentrate with discharge openings through which concentrate may flow. A plurality of conduits are coupled to the discharge openings and are in fluid communication with concentrate disposed within the containers. A multi-channel linear pump is provided with a pump body or bodies, including bores disposed within the pump bodies, pistons operatively mounted within the bores for reciprocation and piston shafts connected to the pistons. An A.C. synchronous motor is connected to the piston shafts for imparting constant-speed reciprocal motion to the piston shafts and to the pistons disposed within the bores. Inlet ports are in fluid communication with the conduits and bores for supplying concentrate thereto during a reciprocal motion of the pistons in a first direction.

Abstract: The device for the compression of a gas comprises a motor (1), a piston (2) adapted to be displaced linearly in a pump body, transmission means (T) between the motor (1) and the piston (2) adapted to convert the rotary motion generated by the motor (1) into a reciprocating translatory motion by the piston (2). Speed varying means comprising a cam (12) are provided to impart a different speed to the piston (2) of the compressor according to the resistance opposing the motor (1) during one complete admission/compression cycle, so that the resisting torque is substantially constant and so that the motor (1) operates at its maximum torque and therefore at maximum efficiency. The section of the cam (12) is determined so as to ensure substantially isothermal compression of the gas.

Abstract: A concentrate supply assembly for a post-mix beverage dispenser includes a plurality of containers for concentrate with discharge openings through which concentrate may flow. A plurality of conduits are coupled to the discharge openings and are in fluid communication with concentrate disposed within the containers. A multi-channel linear pump is provided with a pump body or bodies, including bores disposed within the pump bodies, pistons operatively mounted within the bores for reciprocation and piston shafts connected to the pistons. An A.C. synchronous motor is connected to the piston shafts for imparting constant-speed reciprocal motion to the piston shafts and to the pistons disposed within the bores. Inlet ports are in fluid communication with the conduits and bores for supplying concentrate thereto during a reciprocal motion of the pistons in a first direction.

Abstract: A steam turbine control valve actuator for lever-operated control valves includes a servomechanical actuator with a reciprocable rod. Such servomechanical actuator is mounted upon a support assembly that is, in turn, pivotably mounted to the control valve body. A distal end of the rod is coupled by a knuckle joint to one end of the lever which operates the control valve, and forces of the rod are biased by a spring that substantially eliminates side forces on the rod through maintenance of the effort that is applied to the lever by the rod in a direction that is parallel to the rod.

Abstract: A fluid pressure actuated clamp or gripper includes a mechanism housing mounted upon and projecting forwardly from the front end of the fluid pressure motor housing to define a passage loosely enclosing the projecting portion of the piston rod of the motor. The mechanism housing is split from front to rear into two separable halves and aligned bores through the housing halves detachably receive the opposite ends of a pivot pin upon which elements of the clamp or gripper mechanisms are mounted. A carrier fixedly mounted on the piston rod within the mechanism housing passage detachably mounts resilient bumper members engageable with the front end wall of the motor housing to define a resiliently cushioned rearward end limit of movement of the piston rod.

Abstract: A fluid actuator including a pair of hingedly interconnected members between which is located a fluid expansible element such as a bellows which may be expanded upon application of fluid pressure to cause pivotal movement of the hingedly interconnected members. The actuator may also include a further pair of hingedly interconnected members which are themselves hinged to the first pair of members and which define with the first pair of members a space for receipt of the fluid expansible element.

Abstract: An actuator having a tubular body with a cylindrical bore therein within which a piston reciprocates, an output shaft extending into said bore and a linkage for converting the linear movement of the piston into the rotary motion of said shaft. The linkage is contained entirely within said bore. In one form the piston is spring loaded and a spring follower also provides a piston for compressing the spring to permit the force exerted on the piston to be transmitted to the output shaft substantially in its entirety.

Abstract: A tread brake unit including a spring actuated compensating mechanism for maintaining the brake unit piston stroke constant. A roller associated with the compensating mechanism is adapted to ride along an operating surface of a lever arm that rotates according to the degree of piston stroke. The profile of this operating surface regulates the roller movement to prevent the stressing of operating springs in the compensating mechanism from exceeding a maximum value corresponding to their fatigue limit.

Abstract: An air compressor in which a piston is reciprocated in a cylinder by means of an eccentric. The eccentric is connected to the piston by means of a linkage consisting of an arm, a connecting rod and a control link. By virtue of the arm and the control link, the speed of the piston is greatly reduced as the piston approaches the terminal end of its compression stroke.

Abstract: A displacement apparatus for allowing relative displacement between two reciprocating members such that a predetermined output motion profile of one of the members may be obtained relative to the motion of the other of the reciprocating members.

Abstract: An actuating cylinder having a fluid pressure operated piston member connected by a friction member to a push rod to which a brake shoe, or the like, may be attached as the output member. A force transfer lever is arranged between the piston and push rod to transmit the piston force to the output member with mechanical advantage only after the friction connection is overcome by resistance at the push rod, such as occurs by engagement of the brake shoe with the wheel of a railway vehicle.

Abstract: There is provided a connecting rod for connecting a crank pin of an electric motor to a reciprocated piston. The connecting rod includes a sheet metal shaped member that at each end has a deep drawn cylinder mounting which in turn mounts a bushing that is of a greater axial length than the cylinder mounting. The shaped member has a longitudinal bead providing a depression extending adjacent to one of the mountings and terminate in spaced relationship to the other mounting whereby there is a planar surface extending transversely across the member longitudinally between the bead and the other mounting and adjacent to the widest part of the member to provide a bending line.

Abstract: A fluid-operated actuator for collets, vises, chucks and other workpiece engagement devices, for example, the actuator having a piston which moves the engagement device toward the workpiece with a force equal to product of the area of the face of the piston times the pressure of a fluid applied to the face. When the engagement device has engaged the workpiece, additional, relatively slight movement of the piston causes a force multiplying mechanism to provide increased engagement force without increasing the pressure of the actuating fluid. The overall travel of the actuator mechanism is not limited by the force-mulitplying mechanism which begins to function only after the unrelated distance of travel of the engagement device to the workpiece. Thus, for example, compressed air at ordinary shop pressures may be used to actuate collets or chucks on automatic lathes or the like to provide relatively high clamping forces.

Abstract: The invention, a high-pressure, reciprocating, gas compressor, employs labyrinths to create gas sealing, annular, air dams between the piston and cylinder bore, and piston rod and an aperture in an end wall or closure of the cylinder through which the rod translates, and active magnetic bearings to maintain the piston and rod at their centroids, equally and minutely spaced, fully thereabout, within the bore and aperture. Too, the drive mechanism, a scotch yoke arrangement, has further, active magnetic bearings, to centralize a drive shaft in its housing, and to effect a non-contacting travel of the drive shaft's offset crank, which translates the piston rod, within the yoke.

Abstract: A fluid actuator having a piston, a pair of springs, a pair of cams, and a pair of cam followers mounted in a housing. A normally open valve is coupled to the actuator output shaft for actuation. When fluid pressure is applied to the piston, the springs are compressed, and the cam followers are moved down to permit the cams to rotate away from each other, thereby reducing the force on the actuator output shaft and permitting the valve to open. When fluid pressure is removed from the piston, the springs expand pushing the piston and the cam followers up, thereby rotating the cams toward each other and forcing the actuator output shaft against the valve stem to close the valve.

Abstract: A pumping unit has a drive train comprising a very large mass including large diameter series connected sheaves, one of which is a large crank sheave. The crank sheave is directly connected to a pitman arm which oscillates a walking beam, which in turn reciprocates a horsehead attached to a bridle. The bridle is connected to a polished rod associated with a downhole pump. The crank wheel, pitman arm, and rocking beam are arranged respective to one another to cause the tail bearing to oscillate predominantly in the second quadrant, and to cause the center of gravity of the pitman arm to be located predominantly between the vertical axis of the crank wheel and the Samson post bearing. The geometry of the crank wheel, pitman arm, and rocking beam provides substantially constant, positional of the polish rod on the downstroke, with rapid positional occurring at peak polish rod velocity, which causes a longer downhole pump stroke because of the induced elongation of the sucker rod string.

Abstract: A fluid-powered rotary actuator particularly well suited for use in operating an aircraft flight control surface. The body has a stationary body portion and a rotatable body portion with an elongated annular sleeve reciprocally and coaxially mounted within the body. A tie-rod coaxially projects through the sleeve from end-to-end between the stationary and rotatable body portions to maintain their relative longitudinal position against axial separation during actuator operation. To each axially outward side of the sleeve is an annular ball deflector. The axially outward portions of the sleeve and the corresponding portions of the stationary and rotatable body portions have helical ball races formed therein to transmit torque between the body portions and the sleeve to cause the rotatable body portion to rotate in response to fluid-powered linear reciprocation of the sleeve.

Abstract: A fluid actuator characterized by a feedback mechanism for indicating actuator position. The feedback mechanism is driven by the actuator screw shaft, whereby the movements of the feedback mechanism are proportional to the rate and position of the actuator movements. The feedback mechanism and actuator movements may be synchronized so that the extreme end positions of the feedback mechanism will correspond to the fully retracted and extended positions of the actuator. A stroke limiting mechanism may also be provided for preventing the actuator from overstroking the feedback mechanism in the event that they are not properly synchronized.

Abstract: A linear to rotary actuator is disclosed having a fluid pressure operated diaphragm whose linear movement is translated into rotary movement of an output member by a helical coupling therebetween. The coupling comprises a coupling member that is insert molded in the diaphram so as to extend therethrough and interlock therewith while preventing fluid from passing from one diaphragm side to the other. The coupling member has a combined guide and anti-rotation portion extending from one side of the diaphragm that slidably engages a stationary guide so as to guide linear movement while preventing rotational movement of the coupling member and further has a helix extending from the other side of the diaphragm that slidably engages in a slot in a section that meshes with a gear connected to the output member whereby linear movement of the diaphragm forces linear non-rotational movement of the coupling memmer and thereby rotary movement of the output member.

Abstract: A rotary mechanism for converting a reciprocal linear motion into an oscillating rotary motion with increased torque at the end positions. Two pressurized air cylinders 1,2 co-operate via links 14, 15 with a common lever arm 5 fastened to an output shaft. The cylinders provide an increased torque adjacent to each one of the end positions of the rotary motion.

Abstract: A variable-stroke, constant-compression, reversible radial pump, the stroke of which may be infinitely adjusted by means of a variable-throw eccentric from a normal-cycle maximum through zero to a reverse-cycle maximum, and the compression of which is maintained constant through the use of a variable-geometry cylinder-head assembly. The cylinder geometry varies when the cylinder head is raised and lowered by means of a synchronized screw arrangement which is coupled through a gear set to the variable-throw eccentric. The variable throw-eccentric comprises a hollow input shaft which is drilled and threaded diametrically. A threaded, splined adjustment shaft is screwed into the threaded diametric hole in the input shaft. Each end of the adjustment shaft is mounted in bearing races which are anchored at diametrically opposed points in a connecting-rod journal.

Abstract: In an integral Stirling cryogenic refrigerator the compressor piston is several times heavier than the displacer. In order to counterbalance both the displacer and compressor piston with a rotating counterweight, the displacer connecting rod is formed of a high density material. Specifically, the connecting rod is formed of a tungsten alloy and is several times heavier than the displacer.

Abstract: A pair of spaced rotatable shafts are mounted within a housing. A linear motor mounted to the housing has a reciprocating piston within a double action piston chamber whose piston rod projects from the piston. Both shafts are fixed directly to axially aligned rotary valve stems, to opposite sides of the reciprocating piston rod. A pin coupled to the end of the piston rod projects through longitudinal slots within radial arms fixed to respective shafts at different levels and rotating with the shafts. Equal sized gears mounted to the shafts are in peripheral mesh such that the shafts rotate in unison. The mechanism eliminates side thrust on the piston and piston rod, doubles the valve breakout forces applied to the rotary valve member and eliminates the need for an outboard bushing for a piston rod extension beyond its connection to the paired shafts.

Abstract: A positive displacement pump has a cylinder closed at one end and a plunger projecting from the opposite end reciprocable therein. Rings and packing are inserted at the opposite end to guide the plunger and are designed to provide that the plunger has a material clearance from the cylinder walls. To use a different sized plunger the rings and packing are designed for easy removal at the end of the cylinder and for replacement by rings and plunger corresponding to the new plunger section. A convenient manual linkage is provided for manual operation of the pump with the cylinder upright. A convenient horizontal frame is provided for the pump with a drive means for the pump used with the cylinder in a horizontal position.

Abstract: A brake power servo booster, in which a fluid pressure difference is generated between opposite sides of a power piston, is provided with a wedge shaped member which is forced by the power piston between the wedge shaped recess of the members of an output shaft. When the wedge shaped member is forced into the recess by the piston the distance between the members of the output shaft is enlarged.

Abstract: A fluid pump for use down a well, having a pump shell, a flexible bladder, a squeeze plate, two check valves, and a plurality of toggle linkages, and a drive rod. The flexible bladder is positioned between the pump shell and the squeeze plate inside the pump shell, and the toggle linkages pivotally connect the squeeze plate, the drive rod, and the inside surface of the pump shell in a manner that permits with one complete stroke of the drive rod the compression and relaxing of the flexible bladder. The power source, is located at the surface of the earth.

Abstract: Apparatus including a reciprocating piston driven by a connecting means operating within a slider for driving a piston in a reciprocating motion. The slider is mounted in a crank case housing and includes guides for maintaining the orientation of the piston relative to surrounding cylinder walls. The cylinder is attached to the crank case housing at one end and attached to a cylinder head at the opposite end. The cylinder head includes an intake valve and an exhaust valve for controlling the flow of fluid into and from the piston chamber. To drive the piston a crank shaft is rotatably attached to a connecting means that rotates within the slider and connects thereto. Fastened to the crank shaft is a flexible coupling for coupling the crank shaft to a source of driving power.

Abstract: Disclosed is an overload protection apparatus for variable pitch propellers, particularly cycloidal propellers. The apparatus is of the kind having a hydraulic servomotor (2) with an adjustment rod (1) for actuating a propeller, and having mechanical restoration means comprising an auxilliary adjustment means for adjusting a restoring lever (5) via an intermediate lever (6). As disclosed, the restoring lever (5) is pivotally linked to a first arm of the intermediate lever (6) which in turn is pivotally mounted on said adjustment rod (1) at a fulcrum (9). The first and second arms of the intermediate lever extend from opposite sides of the fulcrum. The second arm of the intermediate lever preferably includes a slideway (15) which receives a slide-shoe (16) affixed to an auxilliary adjustment lever (7), which is preferably an angular lever on which the auxilliary adjustment means acts at the end (12).

Abstract: A force amplifying displacement device for displacement of an object (5) a predetermined distance relative to a frame (2) or the like, wherein a first, longer part of the displacement movement requires a relatively minor force, while a second, shorter part of the movement requires a substantially greater force. The device comprises a lever mechanism (13) active between the frame (2) and a power transmission rod (17). An operating unit (9), e.g. consisting of a pressurized fluid cylinder (10), piston (11) and piston rod (12), first operates directly between the object (5) and the frame (2,22) and, thereafter, by sensing the end portion (28) of the power transmission rod (7), by way of the lever mechanism (13), so that a strongly amplified force is applied to the power transmission rod (7) and the object (5).

Abstract: A valve driving apparatus is provided with cylindrical bearing members made of a synthetic resin or a copper alloy and used for a piston rod and for a drive shaft, a lining member made of a synthetic resin for coating the inner wall of an apparatus and a resilient member made of a synthetic rubber or a synthetic resin and inserted in a groove of a piston so as to protect the valve driving apparatus from the disadvantages of wear, frictional resistance and energy loss which are produced by a reciprocating movement of the piston and the piston rod. Also a valve driving apparatus utilizing a scotch yoke type movement conversion-transmission mechanism is provided with cylindrical bearing members made of a synthetic resin or a copper alloy and attached to pins installed on a piston rod so as to prevent the aforementioned disadvantages from occurring between the pins and the scotch yokes.

Abstract: A vehicle brake system in which an output member is axially displaceable by the application of differential fluid pressure, under the control of a valve operable by an input member, across a movable internal wall which divides a housing of the booster into a pair of fluid chambers. Displacement of the movable wall is communicated to the output member via a lever mechanism providing a mechanical advantage between said movable wall and the output member. The lever mechanism comprises first and second levers. The second lever is pivotable relative to the input and output members at respective pivot points.

Abstract: An acceleration pump for a carburetor incorporating first and second pump levers rockably secured to the carburetor body and moved via an acceleration rod connected at one end to the pump lever and a throttle lever connected at one end to the acceleration rod by a throttle valve rockably installed within the barrel of the carburetor, thereby telescopically moving a pump rod secured to a piston of a piston type acceleration pump or to a diaphragm of a diaphragm type acceleration pump. The acceleration pump thus employing the first and second pump levers can obtain an ideal fuel flow curve by increasing the fuel injection time thereof into the air intake opening of the carburetor to improve the exhaust gas purification while improving the drivability and acceleration of a vehicle by preventing a temporarily lean air/fuel ratio of the air/fuel mixture supplied to the carburetor immediately after the acceleration of the vehicle.

Abstract: The ram housings of a volumetric metering stuffer are provided with ram seals to prevent leakage of the product being stuffed. The rams are reciprocated translatorily along substantially straight lines to prevent sidewise thrust on the seals. Cushions absorb the shock incident to the ends of the strokes of the rams and provide smooth deceleration thereof. Each ram has a clean-up cage to receive the ram when the ram is withdrawn from its housing.

Abstract: A fluid pressure motor having a movable diaphragm assembly and an output assembly housing a plurality of output members at least some of which can move relative to the diaphragm assembly and can be connected to separate devices for control by a single differential control pressure in the motor.

Abstract: The invention relates to a servo motor assembly in which the linkage is provided between a linearly movable motor part and a rotatable member being controlled. The linkage includes two separate links and the arrangement prevents or minimizes lateral reaction forces from being applied to the linearly movable motor part which would cause undue wear on the bearings thereof.

Abstract: A lever arrangement for providing a servomotor in a power braking system with a variable operational output force. The servomotor has a wall moved by a pressure differential to create an initial output force. The lever arrangement is attached to the servomotor and modifies the initial output force from the wall to create the variable operational output force which is supplied to a master cylinder.

Abstract: A mechanical movement is provided for converting between linear and rotational movement and includes a frame adapted to move only along a linear path of travel. A first rotatable member is adapted to bear against the frame in such a manner that the first rotatable member is free to rotate with respect to the frame. A second rotatable member is adapted to bear against the first rotatable member in such a manner that the second rotatable member is free to rotate with respect to the first rotatable member in an eccentric fashion. A third rotatable member is affixed to the second rotatable member and is adapted to rotate therewith about a fixed axis. Means are provided for minimizing the sideward thrust on the first and second rotatable members so that linear movement of the frame will be converted to rotational movement of the third rotatable member and so that rotational movement of the third rotatable member will be converted to linear movement of the frame.

Abstract: A linear piston operator having a cylinder enclosing at least one piston, a connector bar connected to said piston and an oscillatable element operatively connecting the connector bar to a rotary shaft extending transversely and tangentially of the cylinder. The oscillatable element extends through a longitudinal slot in the cylinder wall, and the shaft end of the element is enclosed in a housing having two longitudinal reinforcing portions extending along and welded to the sides of the slot, said shaft being journaled in said reinforcing portions.

Abstract: In working cylinders whose power stroke can be shifted to different operating positions in two consecutive steps, the invention provides a control cylinder which is actuated independently of the generation of working pressure. The control cylinder acts on a joint lever which alters the distance between two separate parts of the power transmission to the tool and thus the effective length of the transmission. This arrangement has the advantage of small working volumes and low energy consumption.

Abstract: A device for interconverting linear and rotatory motions, and particularly a pressure fluid operated actuator for rotary plug valves and the like. A piston axially slideable and rotatable in a cylinder is supported by first and second sets of connecting elements which are spaced from and inclined to the axis of the cylinder. Each element of one set is pivotally connected at one end with a fixed member and at the other with the piston. Each element of the other set is pivotally connected at one end with the piston and at the other with a rotary output element, for example, a shaft. Axial movement of the piston is translated into rotatory movement of the output element by pivotal action of the connecting elements. The connecting elements of the first and second sets extend from the fixed member to the piston and from the piston to the output element in opposite circumferential directions.