Abstract: The invention relates to a hydraulic unit for feeding an object at a desired feed speed a distance in a given feed direction during a working stroke and, in a return stroke, bringing the object back to the initial position at a considerably greater return speed, comprising a double-acting working cylinder (1) with a piston (16), the piston rod (17) of which is connected to the object which is to be moved, and a receiver cylinder (2) which is provided with a second piston (28) and designed to be filled with oil from the working cylinder during the return stroke, the first piston (16) and the second piston (28) being interconnected by a rigid connecting member (31) which forces the second piston to follow the movements of the first piston.

Abstract: The electrohydraulic adjusting device for actuating a device for adjusting at least one camshaft of an internal combustion engine relative to its crankshaft has two differential pistons each of which serves to adjust a camshaft (intake camshaft or exhaust camshaft). Each of the two differential pistons have a small effective piston surface which is acted upon with pressure by a pump. An independent pressure control valve is associated with each of the pressure chambers on a larger effective piston surface, via which valve, the pressure in this pressure chamber can be controlled independently of the other differential piston.

Abstract: A hydraulic system having a high-pressure differential cylinder implemented as a servo actuator is hydraulically connected to a valve combination and an electro-hydraulic servo valve. The valve combination is a multi-functional valve including multiple interengaging valves and correcting elements all disposed within a housing. The valves and correcting elements are positioned and engaged along a functional axis of the multi-functional valve. This combination of valves provides for a single lightweight housing for the valve. The multi-functional valve is hydraulically connected via conduits with the servo valve and the differential cylinder. This device allows for the use of a single valve arrangement for controlling the numerous operating modes of the differential cylinder or servo actuator.

Abstract: An actuator for use in an active suspension system is controlled by a valve responsive to differential pressure across the piston of the actuator. The valve operates to allow movement of the piston so as to reduce the pressure differential. The valve is also controlled by signals indicative of position of and load applied to the actuator.

Abstract: A hydraulic device for a hydraulic drive for a high-voltage circuit-breaker includes a drive piston for a movable contact piece having two piston sides being in connection with a high-pressure reservoir in a closed condition and being acted upon by high-pressure fluid on both sides. For circuit-breaking, a switch-over valve releases a path to a low-pressure space for the fluid in the space with the larger piston area. At least one circuit-closing pilot valve and circuit-breaking pilot valve activate the switch-over valve. A settable delay volume for the fluid is connected in parallel with at least the at least one circuit-breaking pilot valve.

Abstract: The hydraulic setting device has a differential cylinder (11) whose annular space (14) is continually subjected to pressure by a pump (16). The pressure space (18) at the large piston surface is connected to the pump via a connection conduit (41). A conduit branch, which leads to a control valve (21), emerges from this connection conduit (41). At the other end, this control valve is in connection with a return conduit (26). The pressure in the conduit branch (19), and therefore in the pressure spaces (14, 18) of the differential cylinder, can be varied by appropriate activation of the control valve.

Abstract: A marine hydraulic system for operation of a power steering assembly includes a pressure accumulator to provide pressurized hydraulic fluid and valving that permits the transfer of hydraulic fluid within the cylinder to provide efficient use of hydraulic fluid.

Abstract: A hydraulic cylinder assembly for use in a variable external pressure envnment is provided. A hydraulic cylinder exposed to the variable external pressure environment has two chambers separated from one another by a piston. Hydraulic fluid fills each of the two chambers. In an "at rest" mode, the hydraulic fluid in the two chambers is pressurized to the variable external pressure. In an "at work" mode, pressure of the hydraulic fluid is selectively varied from the variable external pressure in one of the two chambers such that the piston moves. The entire assembly can be installed between the pressure and outer hulls of a submarine and utilize seawater to equalize the pressure in a balanced power stroke circuit.

Abstract: A hydraulic servo unit for changing the swash plate angle of a continuously variable transmission to vary its speed reduction ratio comprises a cylinder whose chamber is divided into a rod-side chamber and a head-side chamber by a piston slidably fitted therein. The rod-side chamber is supplied with working oil under predetermined hydraulic pressure through a first hydraulic pressure supply passage. A second hydraulic pressure supply passage is connected to the head-side chamber through a duty-cycle-controlled first solenoid-operated valve, and a drain hydraulic passage is connected to the second hydraulic pressure supply passage through a second duty-cycle-controlled solenoid-operated valve. The first and second solenoid-operated valves are simultaneously actuated with different duty cycles.

Abstract: In a driving mechanism of a circuit breaker having first and second hydraulic operation apparatuses respectively driving a main contact and a resistor contact, a sequential control valve is provided between the first and second hydraulic operation apparatuses. The sequential control valve detects the operation of a differential piston for opening the main contact and switching the differential piston for sequentially opening the resistor contact after the opening of the main contact.

Abstract: A hydraulic actuator includes a pneumatic piston, a hydraulic piston, and an engine valve on a common shaft. The pneumatic piston is urged between first and second stable positions primarily by a double acting pneumatic spring, with high pressure hydraulic fluid connected to a first hydraulic chamber being used to cock the hydraulic piston in a first stable position (engine valve closed). Hydraulic fluid isolated in a second hydraulic chamber is used to latch the hydraulic piston in a second stable position (engine valve open). Transfer of hydraulic fluid between first and second chambers is effected by a carrier for two check valves, which carrier in a first position disables the second check valve to permit fluid to flow from the second chamber to the first chamber, whereupon the first check valve closes (cocking). In a second position the carrier disables the first check valve to permit fluid to flow from the first chamber to the second chamber, whereupon the second check valve closes (latching).

Abstract: A marine hydraulic system for operation of a power steering assembly includes a pressure accumulator to provide pressurized hydraulic fluid and valving that permits the transfer of hydraulic fluid within the cylinder to provide efficient use of hydraulic fluid.

Abstract: The present invention relates to a valve assembly (10) which is mounted on a part (piston unit 40) of an air motor (10) arranged for reciprocating movement in a housing (cylinder 12). The valve assembly includes a first valve unit (50), which is mounted on one side of the part (40), and a second valve unit (70), which is mounted on the other side of the part (40). The second valve unit is connected to the first valve unit (50) by means of the part (40) for common movement with the first valve unit relative to the part (40) when the valve assembly is switched as the part (40) reaches one of its two end turning-positions.

Abstract: An automatically sequenced hydraulic cylinder mechanism, including a hydraulic cylinder having a piston rod which is attached to a working member. The hydraulic system includes a pump which supplies hydraulic fluid to opposite sides of the cylinder. Due to the differential in surface area on opposite sides of the piston, the piston is moved in a direction to extend the piston rod. When the piston bottoms out in its stroke of travel, the pressure in the system is increased and the increased pressure will operate a three-position valve to decrease the pressure in one end of the cylinder and automatically retract the piston rod. The cylinder is thus automatically sequenced to extend the piston rod and retract the piston rod without the use of auxiliary switched or sensors.

Abstract: A double acting hydraulic cylinder is a die cushion for a press, with an upper and a lower chamber in communication with each other and with a differential pressure between the two chambers automatically controlled by a valve mechanism. With the differential pressure controlled according to one of several desired curves, the die cushion capability during press operation can be changed and adjusted to a valve suitable for the product to be processed and so a wide variety of products can be produced in high quality and high efficiency.

Abstract: A gas spring actuator which, when attached to a valve, will return the valve to its initial position after the valve has been moved to a second position by application of a pressurized fluid that opposes the gas spring. The gas spring is charged to a predetermined gas pressure. A hydraulic fluid is applied in an opposing manner to drive the piston in one direction to operate the valve and simultaneously pressurize the gas in the gas spring. Upon removal of the hydraulic pressure, the pressurized gas returns the piston, and the valve, to its initial position.

Abstract: A marine hydraulic system for operation of a power steering assembly includes a pressure accumulator to provide pressurized hydraulic fluid and valving that permits the transfer of hydraulic fluid within the cylinder to provide efficient use of hyraulic fluid.

Abstract: In a hydraulic servo unit comprising a cylinder and a piston slidably inserted therein, the cylinder chamber being divided by a piston portion into a rod-side cylinder chamber and a head-side cylinder chamber, a control apparatus for the hydraulic servo unit includes but is not limited to a first hydraulic line connecting the rod-side cylinder chamber with the hydraulic pressure source which supplies working fluid of a predetermined pressure, a second hydraulic line connecting the head-side cylinder chamber with the first hydraulic line through a first solenoid valve of duty-ratio-control, and a drain hydraulic line connecting the head-side cylinder chamber with drain through a second solenoid valve of duty-ratio-control.

Abstract: A means for receiving and subsequently emptying hydraulic fluid from a hydraulic system is described. It comprises a working cylinder (1) and a supply conduit (8) disposed between a pump and the working cylinder for supplying hydraulic fluid at high pressure within a predetermined interval. According to the invention the means also comprises a receiving cylinder (12) with a piston (19), which on one side defines a liquid space (22) for the receipt of hydraulic fluid from the working cylinder with an emptying pressure essentially lower than said high pressure, the piston (19) on the other side defines a chamber (21) containing gas at low pressure, and a high-pressure cylinder (13), which has a liquid space (28) and a plunger (30) movable therein, said liquid space (28) being connected to said supply conduit (8) to receive and return hydraulic fluid at high pressure therefrom and thereto, respectively.

Abstract: A hydraulic control system for the drive control of a double-acting hydraulic cylinder with a larger driving surface and a smaller countersurface, in which the direction- and movement-controlling valve is provided in the form of a follow-up adjusting valve that operates with an electrically-controlled indication of the set value and with a mechanical announcement of the actual position. The pressure source provides two different supply pressures P.sub.N and P.sub.H. A pressure-controlled pressure-reversing valve is provided to switch to the higher supply pressure as and when this is called for by a growing load. A similarly pressure-controlled surface-reversing valve is also provided and, after the pressure-reversing valve has switched to the higher pressure, will itself switch the hydraulic cylinder from a differential operating mode to a mode in which pressure is applied only to the larger working surface of its piston.

Abstract: Disclosed is an apparatus for cleaning the interior of elongated tubular objects such as pipes, tubes, etc., using a reciprocating lance having a cleaning fluid spray head at its end. Fluid pressure provides reciprocating movement to the lance. The cleaning fluid pressure is independent of the fluid which provides movement to the lance, thereby maintaining the desired fluid pressure to the nozzle through the complete cycle of reciprocation.

Abstract: A shaking control unit for a hydraulic cylinder, wherein a first predetermined pressure is admitted to the piston space of the cylinder through a first hydraulic line. A three/two-way valve connects in its zero position a second hydraulic line to a return tank, the second hydraulic line being connected to the first hydraulic line through a check valve. A first control line leads from the first hydraulic line to a first control area of the three/two-way valve. A second control line leads from the second hydraulic line to a second control area of the three/two-way valve. The three/two-way valve is constructed in such a way that, when the pressure in the first hydraulic line reaches a second predetermined pressure which is greater than the first predetermined pressure, the three/two-way valve switches and connects the first hydraulic line to the second hydraulic line. If the piston of the hydraulic cylinder meets an obstacle, the pressure in the first hydraulic line rises above a certain limit value.

Abstract: An actuating assembly having a cylinder which receives a plunger defining a fluid restricting means along its lower end. A feed conduit delivers pressurized fluid through a fluid inlet and into the cylinder, which displaces the plunger out of the cylinder. As the plunger is displaced, the fluid restricting means progressively covers the fluid inlet, progressively restricting the rate of fluid flow into the cylinder, and slowing the plunger's displacement.

Abstract: A control system for mechanically adjustable motor drives which have a shiftable speed control for controlling the speed of the drive. The system includes a double acting pneumatic cylinder which is remotely controlled to shift the speed control by varying the air pressure in the double acting cylinder, to increase or to decrease the speed of the motor drive. The air pressure can be varied manually or by automatic control means.

Abstract: A hydraulic differential cylinder comprises a cylinder, a piston slidably fitted in a cylinder chamber, a piston rod with one end coupled to said piston and an inner valve disposed in said piston rod. The cylinder chamber is divided by the piston into a rod-side cylinder chamber and a head-side cylinder chamber. The piston-pressure-bearing area of the head-side cylinder chamber is greater than the piston-pressure-bearing area of the rod-side cylinder chamber. The rod-side cylinder chamber is connected via the inner valve to a constant hydraulic pressure source. The head-side cylinder chamber is connected to a control hydraulic pressure source.

Abstract: A hydraulic servo cylinder device for controlling a speed reduction ratio or clutch operation in a continuously variable transmission comprises cylinder and a piston slidably fitted in a cylinder chamber of the cylinder. The cylinder chamber is divided by the piston into a rod-side cylinder chamber and a head-side cylinder chamber, the rod-side cylinder chamber being supplied with a hydraulic line pressure, the head-side cylinder chamber being supplied with a hydraulic control pressure. When the piston is moved to a position near a head-side stroke end, the control pressure in the head-side cylinder chamber is so set that a hydraulic force which the piston receives from said control pressure is in equilibrium with a hydraulic force which the piston receives from the line pressure.

Abstract: A 3/2 proportional control valve is provided with an actuating piston which is subjected to the control pressure set in a pilot valve. The area relationships of the actuating piston are so chosen that at the actuating piston a high pressure gradient obtains and the adjustment dynamics of the regulating piston are increased.

Abstract: An electrohydraulic system for control of a variable output pump includes a microprocessor-based controller receiving inputs from condition sensors coupled to the pump and command inputs from a remote master controller. The controller supplies outputs to an electrohydraulic valve for metering hydraulic fluid to a pump control port and thereby controlling pump operation in any one of a number of preselected and prestored pump control modes. A hydromechanical valve is connected in parallel with the electrohydraulic valve for controlling pump operation in the event of electrical malfunction or failure. Circuitry connected between the pump condition sensors and the control computer prevents aliasing errors due to mismatch between the computer sampling frequency and pump speed.

Abstract: A turning gear is used to rotate a turbine rotor under conditions where it is heating up or cooling down without sufficient motive fluid to cause it to rotate. The turning gear avoid the occurence of a thermal bow. A hydraulic turning gear is disclosed for application in confined areas where a substantial force is required to provide rotation to the rotor. A booster cylinder is used to elevate low pressure fluid for use in a reduced diameter hydraulic cylinder. A ratchet wheel and pawl mechanism uses an adjustable friction force to withhold the pawl from the ratchet wheel after initial contact and further employs a stationary guide rail to reset the pawl for the next contact.

Abstract: A shaking control unit for a hydraulic cylinder, wherein a first predetermined pressure is admitted to the piston space of the cylinder through a first hydraulic line. A three/two-way valve connects in its zero position a second hydraulic line to a return tank, the second hydraulic line being connected to the first hydraulic line through a check valve. A first control line leads from the first hydraulic line to a first control area of the three/two-way valve. A second control line leads from the second hydraulic line to a second control area of the three/two-way valve. The three/two-way valve is constructed in such a way that, when the pressure in the first hydraulic line reaches a second predetermined pressure which is greater than the first predetermined pressure, the three/two-way valve switches and connects the first hydraulic line to the second hydraulic line. If the piston of the hydraulic cylinder meets an obstacle, the pressure in the first hydraulic line rises above a certain limit value.

Abstract: This invention relates to an air motor having a snap-acting overcentering spring mechanism for snapping the valving of the air motor between first and second positions as the piston completes each stroke in the cylinder to ensure reliable stall-free operation of the motor.

Abstract: A fluid energized double acting motor is provided for use as the drive for reciprocating mechanisms such as paint pumps for airless spray painting. A piston within the pump housing is moved by pressurized fluid controlled by an automatic reversing valve including spaced check valves. The check valves are selectively seated and unseated by a spring biased piston and fluid pressure controlled valve actuator assembly. The reversing valve system includes anti-stalling features and is of single, low cost, field repairable nature. The motor system also includes features to prevent chattering oscillation due to abrupt changes in motor load.

Abstract: An electrohydraulic control system for a hydraulic working cylinder, for example of a press, the piston of which has a main working surface and a smaller working surface on the rod side. A low-pressure circuit is provided for the feed or retraction movement of the piston, and a high-pressure circuit is provided for the loading movement at increased feed force and reduced speed. The connection or disconnection of these two circuits, when required, is produced with two 3/2 way valves that are coupled together. To control these control valves, there is provided an electrical reference motor that drives a cam disk which brings about the deflection of the coupled control slide valves of the control valves against a spring. A mechanical feedback is provided via the power piston, so that altogether a closed hydromechanical position control circuit is formed.

Abstract: A series of filter backflushing valves are connected to a pressurized air storage tank and are sequentially opened at selectively variable time intervals by a piston and stepping cam structure reciprocably disposed within a cyclic control device intermittently pressure actuated by a backflushing pressure control valve which controls pressurized air flow from the tank to the control device, to actuate the same, through an actuating conduit by automatically opening when the tank pressure reaches a desired backflushing pressure level established by the valve setting. The lapse time between sequential backflushing valve openings may be varied independently of the selectively variable backflushing pressure by adjustment of the flow rate of pressurized supply air into the tank through a main supply conduit.

Abstract: A differential hydraulic jack with a damping system for the control of electric circuit-breakers is provided with a floating ring which produces a damping action at the end of travel and is also provided with a damping extension stud which forms part of the jack piston and penetrates into the damping ring. No provision is made on the jack piston for any packing ring forming a seal with the jack cylinder. The damping ring carries two projecting lips constituting a double valve which forms a leak-tight seal with the bottom face of the jack piston and the internal face of the cylinder end. At the end of the travel of the piston, the damping ring forms a double sealing valve for shutting-off the supply/drain orifice of the jack.

Abstract: A double-acting accelerated forging hammer and method of operation are disclosed. The hammer is of the type having a vertically oriented cylinder, a piston slidably mounted within the cylinder having a downwardly depending piston rod extending along the cylinder and attached to a hammer. A gas accumulator communicates with the cylinder above the piston for supplying gas under pressure thereto during a forging stroke, and a fluid accumulator communicating with the cylinder below the piston for supplying fluid thereto at a higher pressure than the gas to dirve the piston upwardly during a return stroke. A fluid tank supplies fluid to recharge the accumulator and receives fluid from the cylinder during the forging stroke. Variable valves control the rate of fluid flow from the cylinder and thereby control the rate at which the piston descends within the cylinder.

Abstract: An open-center three-way hydraulic valve as applicable to hydraulic control circuits of electric circuit-breakers comprises an admission valve-head which is restored to the closed position by a first spring, a drain valve-head which is displaced toward the closed position by a pilot valve, a second spring which is more powerful than the first and tends to close the drain valve-head, and a resilient semi-locking mechanism for retaining the drain valve-head in the open position in opposition to the second spring when the pilot jack is not under pressure.

Abstract: A hydraulic operating apparatus in which a differential piston is used as a drive unit, and in which the differential piston is driven by applying a high pressure fluid on a large piston face side through a hydraulic pressure control device for controlling the hydraulic pressure, and a high pressure fluid always being applied on the small piston face side. The hydraulic operating apparatus is constructed such that a high pressure fluid is applied concurrently on both piston faces when the differential piston stops at its receded position, and a thrust generated due to the difference between the forces applied on the both piston faces is held in check by a holding device acting on the differential piston or its extension. The differential piston is moved forward upon the removal of the holding force of the holding device, and the piston is moved backward upon the removal of the high pressure fluid on the large piston face side.

Abstract: A control arrangement for hydraulic drives for driving piston pumps includes a control piston which is switchable between its end positions. The control piston has reciprocably effective longitudinally-extending flow restrictors connected into the power lines of the hydraulic drive and the control valves corresponding to each flow restrictor are provided with a pressure balancer. The direction of flow of the hydraulic fluid is the same through all flow restrictors in all switching positions of the control piston. The pressure balancer is controlled by the drop in pressure across the flow restrictor corresponding thereto. The outlet of the control valve for the hydraulic fluid flowing to the hydraulic drive and the inlet for the hydraulic fluid flowing away from the hydraulic drive are connected together at a common connecting terminal of the hydraulic drive.

Abstract: A die cylinder assembly is designed for use in an environment which has contaminants outside the assembly. The die cylinder assembly includes a piston disposed in a cylinder and having an outer end surface. The piston is moved in one direction by forces applied to the outer end surface of the piston. The piston is moved in an opposite direction by a working fluid pressure in a head end chamber of the cylinder. The cylinder includes a rod end variable volume chamber which is connected in fluid communication, through a first passage in the piston rod, with a third chamber located in the piston rod. The fluid pressure in the rod end chamber is always maintained at least as great as ambient fluid pressure to prevent contaminants from entering the rod end chamber. A check valve in a second passage admits outside air to the third chamber when fluid pressure in the third chamber drops below ambient pressure. A relief valve vents the third chamber if fluid pressure therein becomes too high.

Abstract: An actuator for moving a valve or other controlled part in correspondence with variations in an input signal and including a piston movable in opposite directions within a cylinder and having a smaller effective area exposed to fluid in a first chamber at one side of the piston than to fluid in a second chamber at the opposite side of the piston, a pressure fluid source delivering pressurized fluid to the first of these chambers and delivering pressurized fluid to the second chamber through a three way valve having a body containing inlet and outlet openings and a valve element movable relative thereto in a manner varying the pressure delivered to the second chamber of the cylinder.

Abstract: A hydraulic drive includes a pressure housing having a blind axial recess formed therein with a wall and a bottom, an accumulator piston with first and second opposite ends disposed in the recess, an energy accumulator in the form of springs disposed symmetrical to the central axis of the accumulator piston for continuously engaging the accumulator piston braced against the springs, a working piston in the form of a differential piston guided in the recess having a piston rod passing through the accumulator piston and disposed centrally in the pressure housing, the piston rod, the pressure housing and the accumulator piston defining the wall of the recess, the piston rod, the pressure housing, the first end of the accumulator piston and the working piston defining an accumulator space in the form of a hydraulic accumulator providing pressure energy for the hydraulic drive without requiring an external energy supply, the second end of the accumulator piston and the wall and the bottom of the recess defining a

Abstract: The fluid-powered, reciprocating motor includes a cylinder having an inlet chamber and an outlet chamber, a differential area piston mounted in the cylinder, and an output or power shaft connected to the piston. A pressurized fluid, either a gas or a liquid, is continuously introduced into the cylinder inlet chamber and acts on the smaller piston area to move the piston in one direction. A small stream of the fluid flows from the cylinder inlet chamber into the cylinder outlet chamber through a control passage in the piston and is exhausted from the cylinder outlet chamber through an outlet passage until the piston is moved far enough for a valve member carried by the piston to close the outlet passage. Fluid pressure subsequently building up in the cylinder outlet chamber acts on the larger piston area and moves the piston in the opposite direction.

Abstract: A flow-control valve assembly comprises a housing formed with a valve chamber, an inlet port and an outlet port both opening into the valve chamber, a valve seat at one of the ports, and a control chamber. A valve body is displaceable in the valve chamber between a closed end position engaging the seat and blocking flow between the ports and an open end position clear of the seat and permitting flow between the ports through the chamber. This valve body has a valve face exposed to the pressure at the inlet seat in the closed position. A control body in the control chamber has a control face and an oppositely directed counterpressure face. This control body subdivides the control chamber into a control compartment at the control face and a counterpressure compartment at the counterpressure face. The counterpressure face is of greater effective surface area than the valve face.

Abstract: A fluid-pressure driving device including a driving cylinder for producing a driving force, a main control valve for controlling the direction of movement of the driving cylinder and a fluid under pressure, and a pilot valve for controllng the main control valve. The main control valve includes a valve member in the form of a hollow cylinder, and a valve body constituting a part of a cylinder body of the driving cylinder. The valve member of the hollow cylindrical configuration is slidably interposed between the valve body and a sleeve of the pilot valve.

Abstract: Pressure fluid operated servo system method and apparatus including a servo valve operable by an input signal to effect a system output movement; and which servo valve is responsive to the time rate of input signal receipt to vary a gain ratio of system output magnitude compared to input signal value; and method of making such a servo valve.

Abstract: A fluid-pressure driving device including a main actuator unit having a piston adapted to travel a full part of a predetermined stroke and an accelerating actuator unit having a piston adapted to travel only a part of the stroke and being capable of operating only during the acceleration of the object to be actuated. These actuator units are operated under the control of a control valve such that, in the accelerating range in which the speed of the object is still low, both actuator units operate to produce a large actuating force, while, after the acceleration, only the main actuator unit operates to fully travel the required stroke.

Abstract: An apparatus for discharging a high pressure burst of air against a column of standing water behind an obstruction in a drain line to create shockwaves in the water column to remove the obstruction, including a hollow gun body having a discharge opening and a pistol grip handle connected to the gun body. A discharge valve is connected to a piston dividing the interior of the gun body into two chambers, the pressurization and de-pressurization of which is controlled by a trigger operated pilot valve. Air is quickly exhausted from a rearward chamber by depressing the trigger and pilot valve, causing the piston and valve to snap rearwardly to open the discharge opening and direct a burst of pressurized air from a forward chamber to exit through the discharge opening and into a drain line.

Abstract: An asymmetrical vibrator is provided, which is actuated by compressed air. The vibrator operates in a case, which has two bores disposed parallel on opposite sides of the casing. One of the bores is smaller than the second bore and the piston operating in the small bore is called the slow piston, since it is actuated with air to a relatively slow motion and the piston operating in the second larger bore is called the fast piston, since it is moves at a larger speed when driven directly by the compressed air. The asymmetric vibration motion can be employed to transport materials upwardly in factories and assembly stations. The air operated asymmetric vibrators need low maintenance and do not entail the spark dangers caused by the presence of electrical wiring for electrical drive motors.

Abstract: Two solenoid controlled ball valves are employed in such a way that dual w rate control is provided to a missile control vane actuator. The result is the superior performance of an open center valve actuator over that of a closed center valve actuator with gas consumption savings approaching that of the closed center valve design and having the same complexity as a closed center design.