Abstract: An adhesive dispensing module includes a pneumatic actuator for actuating reciprocating movement of a piston on a dispenser valve member. The pneumatic actuator includes a valve element and a pneumatic housing with an inlet chamber, an exhaust chamber, and a piston chamber. The valve element includes a plurality of inlet passages and a plurality of exhaust passages. The valve element rotates from a first position in which the inlet passages deliver pressurized air from the inlet chamber to the piston chamber, to a second position in which the exhaust passages exhaust pressurized air from the piston chamber to the exhaust chamber. The valve element also includes a plurality of fins configured to be driven by an electromagnetic coil to move the valve element.

Abstract: A method for securing the assistance torque (15) supplied by an electric assistance motor (8) in a motor vehicle power steering system includes the steps of: estimating the force on the steering system rack from the torque exerted by the driver on the steering wheel (2), from the assistance torque (15), and optionally from other parameters such as the speed of the electric assistance motor; comparing a target assistance torque with an authorized assistance range, defined with respect to the estimated rack force (17) at any moment, and in the event the target assistance torque is maintained above predefined limits for a predefined duration, correcting and optionally interrupting the power steering.

Abstract: The present invention provides an actuator using a fluid cylinder capable of imparting stiffness to a fluid cylinder such as an air cylinder with a simple constitution, a control method thereof and a choke valve device. The actuator is provided with a fluid cylinder 1, a first choke valve device 3 and a second choke valve device 5. The fluid cylinder 1 has a cylinder chamber 7 and a piston 12 dispose slidably in the cylinder chamber 7 so as to partition the cylinder chamber 7 into a first chamber 9 and a second chamber 11. The first choke valve device 3 is disposed between a fluid pressure source and the first chamber 9; and the second choke valve device 5 is disposed between the fluid pressure source and the second chamber 11. Each of the choke valve devices 3 and 5 is provided with a discharge valve mechanism capable of changing the opening of the valve.

Abstract: The present invention is concerned with a work machine having a telescopic arm coupled to the front thereof. This arm is used for seating various sorts of frontal attachments and is raised and lowered by means of a hydraulic piston-cylinder unit. Now in order to ensure that an installed frontal attachment always rests on the ground with a pre-selected force, use is made of a pilot controlled seat valve and an adjustable pressure regulating valve which ensure that a constant pressure is maintained in the cylinder chamber formed below the base of the piston in the piston-cylinder unit when a constant supply of oil is fed to this part of the cylinder chamber. In consequence, this means that the installed frontal attachment always rests on the ground with one and the same force independently of whether the ground is flat or uneven. The frontal attachment thus precisely copies the contour of the ground at all times.

Abstract: When a start SW 3 is pressed, a one-shot multivibrator circuit 15 turns on and releases a pulse. The pulse is transmitted to a self-hold circuit 16 which in turn stays in self-hold mode and releases an H level output continuously until it is reset. This cause a transistor 17 to turn on and actuate a ram downward movement relay R1. When the ram arrives at the lower limit of its movement, a lower LS 4 is opened causing a self-hold circuit 21 to produce an H level signal in accordance with an output of a one-shot multivibrator 18. The H level signal from the self-hold circuit 21 is delayed by a delay circuit 22 and turns on a transistor 23. As the result, a ram upward movement relay R2 is actuated. Because of the function of the one-shot multivibrator circuit 15, the ram will not restart when the start SW 3 is continuously depressed. The delay circuit 22 contributes to the longer operational life of a directional valve switching mechanism.

Abstract: A fluid controller (15) of the type which controls the flow of fluid to an unequal area steering cylinder (25), wherein the controller is of the load reaction type. The controller (15) includes valving (27) which, when it is in neutral (FIGS. 1 and 5), defines a load reaction fluid path (LR) permitting fluid communication between the control fluid ports (21, and 23) through the fluid meter (29) in response to an external load imposed on the cylinder (25). In accordance with the invention, the valving (27) includes a fluid path (97,95,99,71,75) between the load reaction fluid path (LR) and the return port (19), when the valving is in neutral. When the rod end chamber (A) is contracting, fluid is drawn from the return port into the load reaction fluid path (LR), preventing cavitation, and when the head end chamber (B) is contracting, fluid flows from the load reaction fluid path (LR) to the return port (19), preventing pressure intensification.

Abstract: A fluid controller (15) of the type having a primary, spool valve (43) and a followup, sleeve valve (45) which define a relative neutral position (FIG. 1) and first and second maximum, opposite operating positions (L and R). The controller includes a fluid meter (29) having a member (51) which orbits and rotates. To impart the rotational movement of the member (51) to the follow-up valve (45), the present invention provides a shaft member (53) having a forward end (57) defining a diametral bore (67) with a pin member (69) in close fit relationship in the bore (67) and having ends (71) extending radially into axially elongated slots (75) defined by the sleeve valve (45). The axial length of the slots (75) is sufficient to permit the ends (71) of the pin member (69) to move to and fro as the metering member (51) orbits and rotates.

Abstract: A fluid controller (17) of the dynamic load sensing and flow amplification type, and including a main fluid path (35,39) having a main variable flow control orifice (43), and a fluid meter (37). Dynamic signal fluid enters a load sensing port (29) of the controller and flows through the fluid meter (37) before the main orifice (43) opens, as the controller valving is displaced from neutral to an operating position (FIG. 5). In accordance with the invention, in addition to the normal load sensing drain orifice (LD1) which closes just about the time the main orifice (43) opens, there is provided a load sensing drain orifice (LD2) which remains open somewhat after the main orifice (43) and an amplification orifice (50) open, to prevent build-up of pressure upstream of the fluid meter (37). As a result, there is no flow through the fluid meter (37) until after the amplification orifice (50) opens, and the flow amplification capability appears to the operator to come on instantaneously.

Abstract: A fluid controller (11) of the type comprising a rotatable spool valve (31) and a relatively rotatable follow-up sleeve valve (33), in which fluid flows through a fluid meter (15) of the type in which a star member (39) orbits and rotates as fluid flows through the meter (15). The rotation of the star (39) is transmitted to the sleeve valve (33) to provide follow-up movement thereto. In accordance with the present invention, the star (39) defines a set of internal teeth (41) and a terminal portion (42) of the sleeve valve (33) extends axially into the star and defines a set of external teeth (43), in driven engagement with the internal teeth (41). As a result of the follow-up arrangement of the invention, the need for the conventional drive shaft and transverse pin is eliminated, the spool and sleeve can have smaller diameters, and the overall fluid controller can be smaller, less complicated, and less expensive.

Abstract: A power-assisted hydraulic steering system for use in connection with a vehicle having a steering linkage which couples a steering wheel to a vehicle steering actuator, an electrically actuated hydraulic pump, and a tank of hydraulic fluid. The steering system includes a boost cylinder connected to the steering actuator, a hydraulic spool valve fluidly coupling the pump and tank to the boost cylinder, and a switch coupled to the pump. A spool which is mechanically coupled to the steering actuator is mounted within the valve for reciprocal motion between neutral, extended and retracted positions, and is biased to the neutral position by a centering spring which establishes a power-assist threshold. The switch senses the position of the spool, and switches the pump on when the spool is in the extended and retracted positions.

Abstract: A fluid controller (15) for use with an unequal area cylinder (25) having a rod end area A and a head end area B. The controller valving (27) includes, in one embodiment, a flow amplification path (101) for only one direction of steering. In another embodiment, the controller valving (27) includes flow amplification in both directions of steering, but with the ratios being different. In either case, the ratio of flow to the head end to flow to the rod end equals the ratio B/A, whereby the fluid controller requires the same number of turns, lock-to-lock, for either direction of steering.

Abstract: A fluid controller (17) having a housing (21) and valving including a spool (41) and a follow-up sleeve (43). The spool and sleeve define a central reference plane (RP) with the housing having two annular chambers (61, 62) receiving pressurized fluid from an inlet port (23). One of the annular chambers (61) communicates pressurized fluid to the main flow control orifice (A1) in a left turn, and to the flow amplification orifice (AQ) in a right turn, while the other annular chamber (62) communicates pressurized fluid to the main flow control orifice (A1) in a right turn, and to the flow amplification orifice (AQ) in a left turn. A check valve (103,105) is associated with each of the annular chambers, such that one check valve (103) is an inlet check in a right turn and a reverse flow prevention check while manually steering in a left turn, whereas the other check valve (105) is an inlet check in a left turn and a reverse flow prevention check while manually steering in a right turn.

Abstract: A fluid controller (17) is disclosed of the type including a relatively rotatable valve spool (95) and valve sleeve (97) which define a series of variable control orifices (71-76) during normal steering operations. Fluid flow to a control port (27) is controlled by a variable control orifice (74). During small steering corrections, at relatively small valve displacements, the present invention provides an additional variable control orifice (155), which opens before the control orifice (74) opens. A form of check valve (153) is in series with the additional orifice (155), and downstream thereof, to prevent reverse flow from the control port (27) through the controller. The invention is especially beneficial in controllers of the dynamic load signal type including a load signal drain orifice (76) which is open to the system reservoir (R) at the relatively small displacements.

Abstract: A turning-purpose hydraulic circuit characterized in that a discharge passage (20a) of a hydraulic pump (20) is connected to a variable relief valve (21) and a pump port of a directional switching valve (22); a first actuator port and a second actuator port (25, 26) of the said directional switching valve are connected to a turning-purpose hydraulic motor (27); the pilot pressure of a pilot valve (33) is introduced into pressure chambers (31, 32) for controlling a spool in the said directional switching valve and is also introduced into a pressure chamber (40) for controlling a set pressure in the said variable relief valve; a metering-in side portion (42) along which a pressurized oil flows from the said pump port of the said spool to the first or second actuator port is formed with a portion having a configuration such that a flow force may not be produced thereat; and a metering-out side portion (45) along which the pressurized oil flows from the first or second actuator port of the said spool to a tank po

Abstract: A valve has a first set of passages for simultaneously connecting an inlet of a first chamber hydraulically to a source of fluid under pressure and an outlet of a second chamber hydraulically to a venting tank and a second set of passages for simultaneously connecting an inlet of the second chamber hydraulically to the source of fluid under pressure and an outlet of the first chamber hydraulically to the venting tank. The sets of passages are sequentially repositioned to alternately cyclically connect and interrupt hydraulic communication through them. The first and second sets of passages are so configured in relationship to the inlets and outlets that flow through one set is completely terminated only after flow in the other set is initiated.

Abstract: A power steering system (10) for use in a vehicle includes a power steering pump (12) which is driven by an engine (13) of the vehicle. The output from the power steering pump (12) is connected to a power steering valve (22). The power steering valve (22) is connected with a power steering motor (24). When the engine (13) is turned off, that is, in a non-operating condition, and the power steering pump (12) is not being driven, the fluid pressure in motor cylinder chambers (40, 42) is prevented from falling below a predetermined pressure to keep seals (64, 66) in sealing engagement with the power steering motor 24. To keep the fluid pressure in the motor cylinder chambers (40, 42) from falling below a predetermined pressure, a one-way valve (70) blocks the flow of fluid from the power steering valve (22) back to the reservoir (16).

Abstract: A rotary servo valve includes a valve body having a longitudinal bore therethrough. A sleeve fits into the bore. The wall of the sleeve is perforated by two groups of port openings, each group includes a plurality of sets of radially-disposed ports. In each group, the central longitudinal axis of one set of ports is radially displaced from the central longitudinal axis of one other set of ports by a preselected angular displacement. At least a third set of ports in one group is in continuous fluid communication with a source of pressurized fluid; at least a third set of ports in the other group in continuous fluid communication with a return sump. A hollow rotary control member consists of two internal chambers. Each chamber includes a number of sets of apertures that are radially disposed around the walls of the chambers, spaced-apart by a preselected angular separation.

Abstract: A valve member of a three-position, four-way valve is supported to rotate in opposite directions about a predetermined axis from a neutral position to first and second active positions. The valve member is moved between such positions by a manually operable actuator mounted on a pistol grip handle and adapted to be pivoted between a neutral position and first and second actuated positions about an axis offset from and extending perpendicular to the rotational axis of the valve member.

Abstract: A controller (11) and a system for controlling the flow of fluid to a fluid pressure operated device (C) are disclosed. The controller is of the type including a rotatable spool valve (35) and a relatively rotatable sleeve valve (37). Relative rotation between the spool and sleeve define a main fluid path (MFP) and relative axial movement therebetween defines an auxiliary fluid path (AFP). An actuator (65) generates a mechanical output (71) in response to an electrical input signal (CS) to move the sleeve (37) between its neutral axial position (FIG. 6) and an axial operating position (FIG. 7). Axial movement of the sleeve is controlled by a joystick (J). The system includes various sensors (S,PS,G,P), which can sense a predetermined condition and generate an interrupt signal to interrupt or change the gain of the electrical input signal (CS).

Abstract: The mechanism has an actuator provided with a piston, a servo control valve which is actuated by electric input and output signals for supplying working fluid to the actuator and exhausting working fluid from the actuator, a slider which closes an oil passage from the servo control valve to the actuator and which temporarily engages with the piston of the actuator via a link mechanism, when a system for transmitting the input and output signals or the servo control valve breaks down, and a centering valve which is constructed in one body with the slider and which stops supply and exhaust of working fluid after the actuator has been returned to its neutral position by supply of working fluid to the actuator when a system for transmitting the input and output signals or the servo control valve breaks down.

Abstract: A hydrostatic power steering device (11;111) is provided of the type including a primary, spool valve (35;135), and a follow-up, sleeve valve (37;137). During normal operation, relative rotation of the spool and sleeve define one or more variable flow control orifices (A1A5; AN; A1) and these orifices have a first area versus deflection relationship when the sleeve is biased to its first position (FIG. 5; FIG. 10). The sleeve may be moved toward a second position (FIG. 6; FIG. 11) in response to an input (95, 99) other than rotation of the vehicle steering wheel. In the second axial position of the sleeve, the flow control orifice has a different area versus deflection relationship, the difference providing a useful steering or ancillary function.

Abstract: A fluid controller (11) is provided of the type which controls the flow of fluid from a source to at least a first fluid pressure operated device. The controller is of the type including a primary, spool valve (39;39') and a follow-up sleeve valve (41;41'). The spool and sleeve are of the type in which relative rotation therebetween defines a main fluid path through a fluid meter (23), and in which axial movement of the sleeve (39') defines a parallel fluid path (FIG. 7) or an auxiliary fluid path. A neutral centering spring arrangement is provided including at least one compression spring (101) having its ends disposed in engagement with seat members (97,99) to bias the spool and sleeve toward their neutral rotary position.

Abstract: A fluid controller (15) is provided of the type having a primary valve member (53) and a follow-up valve member (55). The controller includes a housing (41) defining main fluid ports (27,29) connected to a steering cylinder (19), and also defines auxiliary fluid ports (31,33), connected to an auxiliary fluid motor (21). The spool and sleeve cooperate with the housing to provide main control valving (35) controlling the flow of fluid to the steering cylinder in response to relative rotation of the spool and sleeve, and auxiliary control valving (35), controlling the flow to the auxiliary motor in response to axial motion of the sleeve, relative to the spool and housing. By performing both the main and auxiliary valving in the spool and sleeve, the main valving (35) is automatically given priority over the auxiliary valving (37), without the need for any expensive, complicated controls or interface between the two types of valving.

Abstract: An improved fluid controller (15) is provided having both rotary valving (47) actuated by the steering wheel (17), and axial valving (49) controlled by an electro-hydraulic valve (113) in response to a correction signal (31). In one embodiment, both the rotary valving and the axial valving are achieved by a primary valve member (63) and a follow-up valve member (65), and both the rotary and axial valving can be actuated simultaneously. Also disclosed is a logic control system for closed-loop control of the electro-hydraulic valve, whereby performance problems such as self-steering wander, drift, and others are substantially eliminated.

Abstract: A fluid controller (15) is disclosed of the type including a primary, spool valve (41) and a rotatable follow-up valve member (43). The controller includes a housing (23) defining an inlet port (31), a return port (33), and control fluid ports (35 and 37). The return port is in communication with an interior chamber (33c) disposed within the spool valve (41). The controller is of the type including a fluid meter (21) through which the fluid flows as part of the main fluid path, imparting the follow-up movement to the follow-up valve member (43). Anti-cavitation check valves (95L, 95R) are disposed in the spool valve, and permit direct communication from the interior chamber of the spool into the main fluid path when the valving returns to neutral (FIGS. 3 and 5) after cavitation occurs.

Abstract: A fluid controller (11) is disclosed for controlling the flow of fluid from a source (73) to a steering cylinder (77), especially for use on large, articulated vehicles. The controller includes a fluid meter (17) and a valving arrangement including a spool (33) and a sleeve (37). The housing and the valving define a main fluid path (113) including a main variable flow control orifice (A1), and the fluid meter (17) in series flow relation between an inlet port (23) and the first control fluid port (27). In accordance with the invention, the main variable flow control orifice is formed by a first fluid passage (93R; 123L) defined by the spool, being in fluid communication with a first fluid port means (101R; 131R) defined by the sleeve. The first fluid port means extends circumferentially to provide continuous fluid communication between the inlet port and the first fluid passage of the spool, as the spool rotates relative to the sleeve from the neutral position to the first operating position.

Abstract: A fluid controller (15) is provided of the type which controls the flow of fluid from a source (11) to a priority device (19) and an auxiliary device (21). The controller includes a valving arrangement (33) comprising a primary, rotatable spool valve (51), and a cooperating, relatively rotatable follow-up sleeve valve member (53). The spool and sleeve cooperate to define controller valving (35) while the sleeve and housing cooperate to define load sensing, priority flow control valving (37). In a preferred embodiment, the controller valving is defined by relative rotation between the spool and the sleeve, while the priority flow control valving is defined by relative axial movement between the sleeve and the housing. The axial position of the sleeve is controlled by fluid pressure in a pilot pressure chamber (95), and in a load signal chamber (103), the difference therebetween representing the pressure differential across a main variable flow control orifice (A1) defined by the controller valving (35).

Abstract: A power steering trim control system for use with steering mechanisms provided in automotive vehicles. The trim system includes a flow distribution valve (38) which selectively directs fluid pressure to segregated groups (34, 36) of valve lands (32) of a rotary valve (24) in proportion to the deflection of a torsion bar (22). The valve lands (32) are angularly off-set from those found in the prior art in order to produce a desired biasing, or torque compensation. The torque which is manually transmitted is progressively supplemented by fluid pressure delivered to the pressure movable part (14) of a steering linkage (16). The invention also includes a process control circuit (60) which is provided with a vehicle speed sensor (60) for generating an electrical signal representative of vehicle speed.

Abstract: A power steering system for a wheeled vehicle comprising a fluid motor connected to dirigible wheels of the vehicle, a power steering pump and a steering valve structure situated in flow delivery and flow return passages that connect the pump with the fluid motor, the valve structure including a pilot-operated solenoid valve means that controls the bypass flow between the supply and return sides of the pump wherein a solenoid actuator is adapted to apply a vehicle speed sensitive force on a pilot valve portion of the valve which develops valve actuating forces on a flow control portion of the valve wherein the latter is speed conscious only and does not depend upon flow to and from the pump nor upon the steering pressure for the fluid motor.

Abstract: A full hydraulic power steering apparatus is provided of the type including a steering unit (2) and a steering cylinder (5). Pressurized fluid is supplied to the steering unit (2) from a pump (6) and compensating valve (10) through a pressure line (8). Conduits (103, 104) communicate from the pressure line (8) to a pair of amplification ports (38, 39) through a pair of open-close valves (105, 106) and check valves (108, 109). A pair of detection members (101, 102) sense the positions of the input handle (1) and the steering cylinder (5), and a controller (100) generates electrical input signals to control operation of the valves (105, 106) to correct any short or over condition of the cylinder (5) relative to its target position as determined by the position of the input handle (1).

Abstract: A fluid controller (11) is provided of the type including a primary, rotatable spool valve (35) and a relatively rotatable follow-up sleeve valve (37). The spool and sleeve define a main fluid path in response to relative rotation, the main fluid path including flow through a fluid meter (17). In accordance with the invention, the spool and sleeve are also moveable axailly relative to each other to define a separate fluid path, in parallel with the main fluid path, the parallel fluid path preferrably excluding the fluid meter (17). Axial actuation of the spool and sleeve relative to each other may be accomplished by controlling fluid pressure in a pair of axial fluid chambers (69, 83). The control of the fluid pressure may be accomplished by any suitable electrohydraulic means (95) or hydromechanical means (181).

Abstract: A hydraulic control mechanism to control operating elements, such as a hydraulic motor, or hydraulic cylinder, employing presetting of a set point, for example via a stepping motor, and mechanical feedback of an actual value. Functional elements are provided in the form of rotary pistons that fit inside one another, rotating relative to one another, and serving for the sensitive regulation of the direction and quantity of a pressure medium stream that is supplied from a pressure medium source to the operting element and flows back therefrom to the tank. One rotary piston is positively connected with the presetting of the set point, and the other rotary piston is positively connected with the operating element for the mechanical actual value feedback. In this way, in contrast to known control mechanisms where a slide or seat valve is actuated by a longitudinal movement, the rotational movement of the set point and actual value are directly compared with one another.

Abstract: The secondary steering system comprises a structure to prevent the reverse flow of fluid in the fluid bypass path around the fluid meter and provide a supply line from the reservoir to the pressurized fluid line. The supply line supplies hydraulic fluid to the fluid meter of the controller when hydraulic pressure has been lost. The fluid meter can then be manually driven by the operator to supply pressurized hydraulic fluid to the steering cylinders.

Abstract: A fluid controller (15) is disclosed for controlling the flow of fluid to fluid pressure operated devices such as a vehicle steering cylinder (17). The controller is of the type including a valve spool (35) and a valve sleeve (37) in which the various ports, passages and fluid paths are non-symmetrical. Metered, pressurized fluid is communicated through axial slots (85) in the valve spool and is communicated through cylinder ports (73) for a right turn condition, or through cylinder ports (75) for a left turn condition. The right turn cylinder ports (73) are located further axially than are the left turn cylinder ports (75) from the end of the spool and sleeve which communicate with the return port. As a result, metered, pressurized fluid has a longer leakage path for a right turn than for a left turn.

Abstract: A direct drive servo valve includes a housing and a series of conduits connecting the housing to a fluid pressure source and to an associated actuator, a sleeve in the housing having a plurality of passageways interconnecting the conduits and a spool valve member rotatable within the sleeve to connect the conduits as desired, the spool valve being rotated by a torque motor. The torque motor rotor is connected to the return side of the fluid pressure source. The sleeve is formed of a series of disks which have a desired pattern of holes therethrough and which are bonded together to create a manifold structure having the desired pattern of passageways. A rotary variable differential transformer is connected to the spool and provides feedback signals to an external circuit controlling the torque motor. A torque rod is connected to the spool and the housing to provide a preload which tends to center or "null out" the spool position when there is no input signal.

Abstract: A fluid controller (17) is disclosed for controlling the flow of fluid to a steering cylinder (19). The controller includes a fluid meter (51) and a valving arrangement (49) including a valve spool (65) and a sleeve (67). The valving (49) defines a main fluid path including a main variable flow control orifice (121), a variable flow control orifice (123), the fluid meter (51), the steering cylinder (19), and a variable flow control orifice (125). In accordance with the invention, the valving (49) defines a dampening fluid path including a variable dampening orifice (133), the dampening fluid path being in parallel with the main fluid path to dampen pressure spikes in the main fluid path. The size of the variable dampening orifice (133), and the flow therethrough, is a function of the relative displacement between the spool (65) and sleeve (67), whereby the timing and amount of the dampening flow and the relationship thereof to the gain curve of the main fluid path can be selected as desired.

Abstract: A valve for controlling fluid flow comprising first and second relatively movable valve members. The first valve member has a first fluid cavity. The second valve member has a second fluid cavity. The second valve member has a land partially defining the second fluid cavity. The land has an outer surface portion and edges on the opposite sides of the outer surface portion. The land has edges on the respective opposite sides of the surface portion. The valve members are relatively movable from the neutral position for directing fluid flow between the first and second fluid cavities across one edge of the land upon relative movement therebetween. A groove in the surface portion of the land provides a reservoir of fluid to be drawn into the fluid flow across the one edge of the land.

Abstract: A control valve is disclosed herein. The control valve includes a valve sleeve and a rotor which is rotatably inserted into the valve sleeve. The valve sleeve have a plurality of fluid passages comprising a plurality of through passages which pass through the wall of the valve sleeve and a plurality of recessed grooves axially elongated on the inside surface of the valve sleeve. The rotor has a plurality of fluid passages opposing with said fluid passages of the valve sleeve. The fluid passages of the rotor cooperate with said fluid passages of the valve sleeve to open and close fluid flow. The valve sleeve has fluid flow noise suppress means formed by many continuous undulations along side edges of the recessed groove of the valve sleeve.

Abstract: A fluid controller (17) is disclosed for controlling the flow of fluid to a steering cylinder (19). The controller includes a fluid meter (51) and a valving arrangement (49) including a valve spool (65) and a sleeve (67), which define a main fluid path including a main variable flow control orifice (121), the fluid meter (51), a variable flow control orifice (123), the steering cylinder (19), and a variable flow control orifice (125). In accordance with the invention, the spool and sleeve define an amplification fluid path including a variable amplification orifice (129) in parallel with the main fluid path, and disposed to amplify the flow of fluid through the meter. In one embodiment of the invention, the amplification fluid path communicates with the main fluid path upstream of the main variable flow control orifice, and at a location downstream of the fluid meter, but upstream of the variable flow control orifice (123).

Abstract: The invention relates to a control device for a hydrostatic steering motor of the type having a slide valve arrangement in which inner and outer sleeves are rotatable relative to each other to both sides of a neutral position through a limited small angle. A bypass throttle between the pump and tank connections of the control device has a dual throttle feature which permits the throttle to be closed after only a small amount of turning away from the neutral position and operates with a reduced amount of noise generated during the turning operations for the same total resistance.

Abstract: Pressurized fluid from an engine driven pump is supplied to and exhausted from the opposed chambers of a hydrostatic power steering servomotor through control passages in a valve housing and in a rotatable valve body coupled through viscous liquid to a steering control shaft. A pressure signal from the pressurized chamber of the servomotor is supplied by the control passages to a valve between the pump and fluid reservoir to limit operating pressure as a function of servomotor loading.

Abstract: The distributor comprises a star-shaped rotor (2) arranged between two concentric components which are spaced axially and are fixed in rotation to a second valve portion (60); a C-shaped centering return spring (40) is arranged around the rotor (2) and cooperates, by its facing ends, with a projection (100) of one of the arms (10.sub.1) of the rotor and with adjacent projections of the second valve portion.

Abstract: The invention relates to a hydrostatic power steering unit of the type having a gerotor gear set forming a metering motor and a valve unit for routing pressurized fluid from an inlet port selectively via expansible chambers of the gerotor gear set to either one of two motor ports while connecting the other one of the motor ports to an outlet port. The housing of the valve unit, which has inner and outer rotary sleeve members, is arranged adjacent the gerotor gear set. A cardan shaft which connects the outer sleeve member to the gerotor star member has a gear head connected to the adjacent end of the outer sleeve member but the shaft itself is disposed mostly in the gerotor star member. The bore of the inner sleeve member has a smaller diameter than that of the shaft head connected to the outer sleeve member and the annularly and axially extending valving grooves of the inner valve member may thus have relatively greater radial depths and thereby relatively greater capacity.

Abstract: A power cylinder for operating a chuck for a machine tool has a rotary cylinder casing, a pair of check valves for confining a pressure fluid in an operating chamber, accumulators for absorbing impacts of the pressure fluid, and detecting means for detecting the fluid pressure in the operating chamber. The power cylinder can be rotated in a state wherein the feeding and discharging of the pressure fluid is stopped.

Abstract: The distributor comprises a primary rotating member having a prolongating portion (11) surrounding coaxially the primary rotating member (5) and forms a seat for at least a C-shaped rection spring (27) the ends of which (48) resiliently been upon a radial finger (37a) secured to the primary member and cooperate in engagement with aperatures (43a) formed in the prolongating portion (11) of the secondary member, thus forming a lost-motion coupling between the two members.

Abstract: A toothbrush is provided with bristles to brush and clean the teeth. Since there are cavities between neighboring teeth it is useful to exercise a multidirectional brushing of the teeth and cavities. The handle of the tooth brush is therefor provided with a fluid motor which is driven by fluid, for example by fluid from the water pipe which is available in the living quarters. The fluid motor revolves a rotary member wherein a space with a therein reciprocable piston is provided. The piston rod engages one end of a lever of a transfer arrangement and swings the lever. The other end of the lever then swings the outgoing shaft of the housing. By attaching a tooth brush to the swinging outgoing shaft the brush can do a multi directional movement for better brushing of the teeth and the cavities between the teeth.

Abstract: In a rack power-steering system, the axial movements of a helical pinion meshing with the rack, resulting from torque applied to the pinion, cause corresponding movements of the movable member of a control valve of the system. This is achieved through a transmission including a piston movable axially with the pinion and defining a variable-volume compartment filled with a substantially-incompressible, deformable material, such as a fluid (oil or grease) or rubber, this material being intended to transmit a control pressure to the movable member of the control valve through a rod which may be formed integrally with the movable member or as a separate member. The variable-volume compartment is located at one end of a cylindrical chamber of the box of the system within which the piston is slidable and the latter is located in a position axially intermediate the variable-volume compartment and an end of the shaft carrying the helical pinion.

Abstract: The distributor, typically one having a star-shaped rotor in a disc-shaped stator, incorporates two components, primary and secondary, defining two parallel distribution circuits (10, 10') controlling an assistance actuator (V) and incorporating, in each circuit, three variable restrictions (1-3 or 1'-3'), together with, advantageously, two other parallel reaction circuits (20, 20') with two restrictions in series (4, 5 and 4', 5'). The chamber (V.sub.1, V.sub.2) of the assistance actuator (V) are joined to the distribution circuits (10, 10'), respectively, between the second (2, 2') and third (3, 3') variable restrictions which create the differential assistance pressure, the central point of the distributor being determined by the first (1, 1') and second (2, 2') variable restrictions.

Abstract: To enable a tool with a hydraulic actuator to be connected directly and quickly to a four-way, three-position control valve, the bodies of the tool and the valve are formed with sockets which receive fittings for establishing fluid communication between the tool and the valve. The fittings are anchored in the sockets of one of the bodies and are adapted to be telescoped slidably into the sockets in the other body to enable the bodies to be quickly and easily connected to and disconnected from one another. The arrangement is such that the same four-way, three-position control valve may be connected either to a tool having a double-acting hydraulic actuator or to a tool having a single-acting hydraulic actuator.

Abstract: A power steering device having a fluid pressure cylinder of a single rod type providing like output characteristics for steering both rightwardly and leftwardly. A rod-side chamber and a head-side chamber of the fluid pressure cylinder have different pressure receiving areas. A control valve controls the changeover of a flow path among a pump, a tank and the rod-side and head-side chambers in accordance with the movement of a steering wheel such that the rod-side chamber is connected to the pump and the tank is connected to the head-side chamber when the piston is to be moved toward the head-side chamber, and the pump is connected to both the head-side chamber and the rod-side chamber when the piston is to be moved toward the rod-side chamber.