Abstract: Aspects of the present disclosure relate to actuator assemblies and related methods for valve systems. In one implementation, an actuator assembly for valves includes an outer housing. The outer housing includes a first internal volume and an inner shoulder portion. The actuator assembly includes an inner housing disposed at least partially in the outer housing. The inner housing includes a second internal volume. The actuator assembly includes one or more first pistons disposed in the first internal volume of the outer housing, and one or more second pistons disposed in the second internal volume of the inner housing. The one or more first pistons are disposed between the one or more second pistons and the inner shoulder portion of the outer housing. The actuator assembly includes an actuator stem disposed through at least a portion of the outer housing and coupled to the one or more second pistons.

Abstract: Actuators having override apparatus are described herein. An example actuator having an override apparatus includes a first actuator stem coupled to a control actuation member. The override apparatus is operatively coupled to the actuator. A spring is coupled to an override member to move the first actuator stem to a predetermined position in response to an override condition.

Abstract: A dispenser for dispensing liquids including an inner displacement member nested in an outer displacement member. The inner member is moveable between two end positions within the outer member by an actuator. The actuator is arranged to move the outer displacement member into a dispensing position when the inner displacement member is in one of its end positions. The displacement members can be pistons and/or bellows.

Abstract: A cylinder chamber 17 at the front of a direct-acting type actuator section 10 is connected to a cylinder chamber 37 at the front of an oscillating type actuator section 30 through a sequence valve with check valve 40. Further, a cylinder chamber 18 in the rear of the direct-acting type actuator section 10 is connected to a cylinder chamber 38 in the rear of the oscillating type actuator 30 through a stop valve 50. Ports 61 and 62 are provided for connecting passages between the cylinder chamber 37 and the sequence valve with check valve 40 and between the cylinder chamber 18 and the stop valve 50, respectively, for distribution control of a working fluid. According to the setting conditions of the respective valves 40 and 50, the piston rod 11 can perform an ordinary reciprocating motion and a motion that combines rotation and advancement.

Abstract: A dual linear actuator for allowing a tool to perform multiple actions either simultaneously or independently of one another.

Abstract: A first piston 13A and a second piston 13B are disposed in a cylinder tube 12A, a hollow piston rod 17 is connected to the second piston 13B, an intermediate stop rod 16 which penetrates the second piston 13B and is fitted into the piston rod 17 is connected to the first piston 13A, a stopper 19 with which the second piston 13B engages is disposed at the tip of the intermediate stop rod 16, and cylinder chambers 14A, 14B and 14C are formed respectively between the first piston 13A and the head cover 12B, between both pistons 13A and 13B, and between the second piston 13B and the rod cover 12C.

Abstract: A pressurized-fluid-operated actuator has two piston surfaces for providing increased output force. The actuator includes a hollow piston that is divided into two inner chambers by a stationary inner dividing wall that is rigidly connected with a cylinder end wall. The piston has an outer diameter that is smaller than the inner diameter of the cylinder, and the piston carries three axially spaced sealing rings that define two axially-spaced annular chambers between the piston and the cylinder. Each of the annular chambers is in fluid communication with a respective port provided in the cylinder wall. Introduction of pressurized fluid into one port causes the fluid pressure to act on a single piston surface to retract the piston and rod, and introduction of pressurized fluid into the other port causes the fluid pressure to act on two axially-spaced piston surfaces to provide an increased output force without increasing the diameter of the cylinder and piston and without increasing the pressure of the fluid.

Abstract: A probe structure for inserting into and operating upon an object within a pipeline, especially a high pressure pipeline carrying liquid or gas, is characterized by two coaxial cylinders that can be either pneumatically or hydraulically actuated. A primary cylinder is adapted to be mounted onto a pipeline tee and/or valve, and includes a movable primary piston to which is fixedly attached a primary lower hollow shaft that moves with the primary piston and preferably a primary upper hollow shaft that also moves with the primary piston. The primary lower hollow shaft is adapted to selectively extend into the pipeline while the primary upper hollow shaft extends above the primary cylinder and is fixed to a secondary cylinder, such that the secondary cylinder moves with the primary piston. The secondary piston includes a secondary piston that moves independently of the first and second cylinders.

Abstract: A multistage switching valve includes a valve stem which is adapted to open or close a fluid passage, a biasing biasing means for biasing the valve stem in a direction to close the fluid passage, a plurality of pistons which are relatively slidably fitted onto the valve stem at different axial positions to provide different flow rates, a plurality of stops which are provided on the valve stem to move the valve stem in a valve opening direction opposite to the direction of the movement of the valve stem caused by the biasing biasing means, together with the pistons when the pistons are moved in the valve opening direction, a valve opening means for exerting a pilot pressure in the valve opening direction on each piston, and a flow rate controller for individually restricting the axial displacements of the pistons in the valve opening direction. A two-stage switching valve and a toggle type two-stage switching valve are also disclosed.

Abstract: The present invention provides an interchangeable modular valve-actuator combination whereby the valve stem on the valve and the actuators are configured to be interchangeably engageable. The components of the valve-actuator are sized accordingly so that when engaged, the valve-actuator combination fits within the confines of an emergency hood located under the dome of a transportable tanker.

Abstract: An intelligent multi-functional hydraulic expanding apparatus includes a hydraulic expanding head, an automatic control hydraulic center, and a depth measuring system. The expanding head includes a hydraulic positioning device, an automatic hydraulic revolving device, a bi-directional cylinder uni-directional pulling type cylinder, and expanding arms that are rigidly connected. As the expanding apparatus adopts steel rope connection, the automatic reviving device performs transfer of torque, multi-arm expanding arms are installed in the same circular cross-section with displacement sensors, computer, and depth measuring system, the present invention provides a solution to the drag problem, increasing efficiency of construction of concrete piles for various foundations of buildings, bridges and obtain pressure angles and depth values so as to improve quality of the construction project.

Abstract: A rotary linear unit possesses a rotary drive and a linear drive. A bearing rod is connected with the drive shaft of the rotary drive, such bearing rod extending coaxially into the output drive unit of the linear drive. On the bearing rod a bearing sleeve is mounted so that it may not rotate while being axially displaceable, such sleeve being fixedly connected with the piston of the linear drive. The piston is divided into two axially sequential piston parts, between which the bearing sleeve is located, which extends into facing receiving recesses in the piston parts.

Abstract: A fluid pressure-operated actuator comprises a cylinder body containing a piston slidable therein, the piston defining respective chambers at opposite sides thereof. A rod projects from one side of the piston and extends through an end wall of the cylinder and a plunger is slidable on the rod and also extends through the end wall. The arrangement is such that the application of fluid pressure simultaneously to the chambers results in movement of the piston lengthwise of the rod, the piston movement including a first part during which the plunger applies force to the rod in addition to that arising on the piston, and a second part during which the force from the plunger is absent.

Abstract: A valve and actuator in combination with a transportation tank to operate off of low pneumatic pressures including a valve having a valve body with a tank end, a valve seat near the tank end of the valve body, the valve seat having a valve sealing surface; a stem chamber extending through the valve body, the stem chamber having an actuator port, a seat port, and an outlet port; a valve stem slidably positioned in the stem chamber, the valve stem having a plug end and a plug attached to the plug end, the plug having a plug sealing surface to sealingly contact the valve sealing surface; an actuator having a hollow housing with a valve end, the valve end attached to the valve body; a plurality of piston assemblies, each having a piston slidable in the housing and a partition fixed in the housing, the piston and the partition defining an actuator chamber; piston spacers joining the pistons so that each piston is fixed in position with respect to the others; the pistons being operatively joined to the valve stem;

Abstract: Pressure medium actuated control cylinder for wear compensation. A cylinder chamber includes two displaceable pistons. One piston has a first piston rod which extends outside the cylinder, and a second piston rod which extends into a through-bore in the second piston. The second piston rod has a bore, into which a rod-shaped resistor extends and penetrates an annular current collector fixed in the bore. The resistor and the current collector form a position sensor in the form of a linear potentiometer which indicates the position of the piston in the cylinder.

Abstract: A hydraulic motor has a longitudinally extended piston cylinder divided longitudinally into two separate and distinct fluid passages by a central divider. Longitudinally midway about the extended piston cylinder is attached a large center piston which provides the primary driving force for operation of the hydraulic motor. Pressurized fluid passes through one fluid passageway formed by the extended cylinder and central divider, and then through ports formed in the piston cylinder into a chamber. The pressurized fluid drives the large center piston, and therefore the piston cylinder, towards the source of fluid pressure being admitted into the piston cylinder. Pressurized fluid is thereby ported from a pressure chamber through the cylinder beyond the longitudinal midway point, and then passed through the cylinder wall to the power piston surface.

Abstract: A valve/actuator combination to operate off of low pneumatic pressures for use on tanker railcars including a valve having a valve body with a tank end, a valve seat near the tank end of the valve body, the valve seat having a valve sealing surface; a stem chamber extending through the valve body, the stem chamber having an actuator port, a seat port, and an outlet port; a valve stem slidably positioned in the stem chamber, the valve stem having a plug end and a plug attached to the plug end, the plug having a plug sealing surface to sealingly contact the valve sealing surface; an actuator having a hollow housing with a valve end, the valve end attached to the valve body; a plurality of piston assemblies, each having a piston slidable in the housing and a partition fixed in the housing, the piston and the partition defining an actuator chamber; piston spacers joining the pistons so that each piston is fixed in position with respect to the others; the pistons being operatively joined to the valve stem; a helic

Abstract: An actuating system for a variable area exhaust nozzle is disclosed having inner and outer flaps pivotally connected to an airframe whose positions may be varied by a single set of control cylinders. The control cylinders have a case in which is slidably mounted a pair of pistons, each having piston rods extending from one side, which piston rods extend through one end of the cylinder case. The piston rods may be arranged coaxially to minimize the bulk of the actuating cylinder. One of the piston rods is connected to the inner flaps, while the other of the piston rods is connected to the outer flaps.

Abstract: An actuator has been developed for actuating a valve for controlling fluid flow in a conduit, the actuator having, in one aspect a housing with a main interior housing space, a rod with a mid-portion, a top end and a bottom end, the mid-portion movably disposed in the housing, the bottom end movably extending from the housing and interconnected with the valve, a first piston member secured to the rod and movable in the housing as the rod moves, a second piston member movably disposed in the housing above the first piston member, the second piston member movable to contact the first piston member, first power apparatus for moving the rod to open or close the valve, and second power apparatus for moving the second piston member to contact the first piston member moving the first piston member and the rod to close the valve. In one aspect the rod has a stop shoulder above the first piston member, and the second piston member is movable to contact the stop shoulder to move the rod.

Abstract: A second pressure intensifying cylinder subchamber is employed for moving a pressure intensifying piston toward the other side, and the necessity for a control valve with a throttle is thereby eliminated. The pressure intensifying piston is incorporated integrally into a fluid cylinder, and, hence, the fluid cylinder can be installed in an even narrow space. A main cylinder chamber communicates with a pressure intensifying cylinder chamber in the interior of the fluid cylinder, and it is therefore possible to prevent such a situation that a high-pressure fluid sprouts out. A structure of the fluid cylinder is thus simplified enough to reduce the costs, and the safety is improved.

Abstract: A hydraulic actuator including a single cylinder body which defined therein a pressure chamber in which a first piston with a piston rod and a second piston with a piston rod are independently movably inserted, a first working member secured to the first piston rod, a second working member secured to the second piston rod, and pressurized fluid inlet and outlet ports provided in the cylinder body to be connected to the pressure chamber.

Abstract: An indexing apparatus (10) having a pair of concentric cylinders (12, 14) with the outer concentric cylinder (12) being fixed against longitudinal movement and the inner cylinder (14) mounted for reciprocal movement relative to the fixed outer cylinder (12). A single ram piston (16) is mounted within the inner cylinder (14) and has a piston rod (18) connected to a member (29) for positioning at four predetermined positions. A shock absorber (24) is carried by the outer fixed cylinder (12) and engages stop plates or abutments (20, 28) carried by the inner cylinder (14) for activation of the shock absorber (24). A pair of guide rods (42) prevent rotational movement of inner cylinder (14) relative to the inner cylinder (12) and maintain the shock absorber (24) in axial alignment with the end abutments (20, 28). In one embodiment (FIGS.

Abstract: A multi-stage hydraulic actuator including a cylinder body having an outer cylinder and an inner cylinder provided in the outer cylinder, first and second pistons inserted in the outer cylinder to independently move and provided with first and second working members, and third and fourth pistons inserted in the inner cylinder to independently move and provided with third and fourth working members.

Abstract: A low-impact drive unit operates by air under pressure. It includes aligned working and pressure chambers. The working chamber contains a working piston and a working piston rod extending from an end of the chamber. The pressure chamber contains a rear outer piston having a cylindrical recess and a central bore. An inner piston is located in the cylindrical recess and has a main piston rod extending through the bore, a bore in a separator separating the chambers, and is affixed to the working piston, so as to move together. The main rod has a longitudinal passage which supplies air from the pressure chamber to the back of the working piston under certain conditions. After the working piston rod contacts a workpiece, force of air pressure on all three pistons act on the working piston rod. An air return passage is provided to return the various components to their initial position after the working operation is complete.

Abstract: The hydraulic cylinder comprises a cylinder jacket (1), a piston-rod guide flange (2), and a cylinder bottom (3). Disposed within the cylinder are a primary piston (4) provided with a piston rod (6) and a secondary piston (11) connected to two plungers (7, 8). The plungers enter two bores (5, 6) in the primary piston. Two spring-biased (19, 20), openable check valves (17, 18) are disposed in the cylinder bottom. In each valve there is a bore (41, 42) connecting the front and rear sides of the valve. The rear portions (24, 25) of the valve chambers (26, 27) each contain a spherical unstopping piston (21, 22). Two supply ducts (23, 30) for the hydraulic fluid are connected to the valve chambers, these chambers in turn having supply ducts at various locations (36, 40, 45) of the interior of the cylinder. A very compact construction is possible for the hydraulic cylinder with pressure transmission.

Abstract: An assembly for moving objects by mechanical linkages has a power cylinder ith a shoulder at the juncture of a small bore and a large bore and with ports adjacent each end and one adjacent the shoulder. A shaft extends through the cylinder with a larger diameter portion in the smaller bore with a piston thereon sealing against the surface of the smaller bore. A second piston slidably seals on the small diameter of the shaft and against the larger bore, being biased towards the shoulder by a spring. A lost motion device on the end of the shaft projects outwardly of the smaller bore end of the power cylinder and has a housing with a chamber in which the end of the shaft is slidable against a spring which biases it outwardly of the housing.

Abstract: A telescopic brake piston includes a cylindrical housing and a pair of concentric pistons. A first hydraulic cavity is provided between an outer piston and the housing, while a second hydraulic cavity, communicating with a source requesting the application of brake force, communicates with both pistons. Passages in the outer piston allow the two cavities to communicate with each other. As the associated brake disc stack wears, the outer piston progressively extends from the housing as the passages are exposed by the inner piston. The actual brake force is attained by the inner piston alone.

Abstract: A remote control shifting system for a mechanical transmission. The transmission is operated by two pneumatic cylinders, a selecting cylinder operating in the direction of shift path selection and a shifting cylinder acting in the direction of shifting. The shifting cylinder operates with two force stages, a lower force for effecting synchronization of gears about to be engaged, and a higher force level for actually engaging or disengaging the selected gears. A remote shift control unit is designed to closely emulate the action of a direct-operating manual shift level. During the synchronizing phase, the shift lever moves easily in the shifting direction. After a preliminary movement, however, further movement is allowed only against considerable resistance, as if conventionally mechanically forcing gears into meshing engagement.

Abstract: The present invention includes a three position actuator which is used to position the gear range control lever on a two speed transfer case. Three positions are required to achieve HIGH, LOW and NEUTRAL. Two individual air chambers may be selectively charged with compressed air to move two pistons along a common actuator rod to achieve linear translation of the control lever to selectively position the transfer case in HIGH, NEUTRAL or LOW range. The transfer case is shifted from LOW to NEUTRAL to HIGH by releasing the charge of compressed air thereby permitting the return spring to shift the control lever to HIGH gear range. Thus, in the event of failure of the system supplying the compressed air, the actuator will return the transfer case to HIGH gear range which provides an appropriate gear range selection for limp home mode.

Abstract: A pneumatic piston/cylinder unit comprises primary and secondary pistons operable in first and second cylinder zones respectively. Each of the primary and secondary pistons divide its respective cylinder zone into two chambers, one of the chambers of the first cylinder zone being connected to one of the chambers of the second cylinder zone via a passageway which includes at least one control for the flow of hydraulic fluid therethrough. A tertiary piston is provided in the one chamber of the first cylinder zone and divides that chamber into two parts, one of which is between the primary and tertiary pistons. In use the passageway, the one chamber of the second cylinder zone and the other part of the one chamber of the first cylinder zone are filled with hydraulic fluid. Application of pneumatic pressure to the other chamber of the first cylinder zone causes the primary piston to be displaced until it abuts the tertiary piston whereupon movement of the primary piston may be arrested or controlled.

Abstract: A fluid-powered actuator for selectively rotating and linearly moving an external device with two fluid ports to communicate pressurized fluid thereto for its operation. The actuator includes a body having a rotatable shaft extending therewithin. The shaft has a chamber with a forward opening and a rearward wall. A first piston is mounted for reciprocal axial movement within said body and means are provided for transmitting torque between the body and shaft to produce rotational movement of the shaft in response to axial movement of the first piston. A second piston having bores extend fully therethrough extends within said shaft chamber and is supported for axial movement relative to said shaft. The external device is attached to the second piston at its forward end.

Abstract: An actuator for opening and closing the gate of a surface safety valve includes a primary piston and an auxiliary piston. The primary drive piston is directly connected to the valve stem, while the auxiliary piston is slideably connected thereto. Extension movement of the auxiliary piston is stopped by a divider plate after initial breakaway forces are overcome. The thrusting force developed by the auxiliary piston during a valve opening operation is transmitted to the valve stem and the primary piston by a shuttle sleeve. The shuttle sleeve is radially spaced about the valve stem, thereby defining a bridge annulus which maintains fluid communication between the primary pressure chamber and the auxiliary pressure chamber at all times. The thrusting force produced by the auxiliary piston is combined with the thrusting force produced by the primary piston to break the static gate seal and overcome the gate drag during a first stage of operation.

Abstract: An improved gate valve having a body with a chamber and an inlet and an outlet extending therethrough into said chamber, a gate mounted for reciprocation in said chamber between open and closed positions, a pressure responsive actuator having a housing, a piston, a connection to the gate and an actuating stem extending from the housing, a supplemental actuator having a connection to the actuator housing, an operating stem connected to the actuating stem, the operating stem having a shoulder facing in the direction opposite to the direction of closing movement of the gate, roller levers pivotally mounted to be in engagement with the exterior of the operating stem and a spring urging the roller levers into tight engagement with the operating stem, the roller levers pivoting on engagement with the stem shoulder to exert a closing force on the stem.

Abstract: A multiple frequency range hydraulic actuator includes a low frequency cylinder with a low frequency actuator piston within. The low frequency piston operates as a high frequency cylinder having a high frequency piston within. The low frequency piston, and high frequency piston operate in conjunction to generate low frequency movement. The high frequency piston operates independently to generate high frequency movement.

Abstract: An improved gate valve having a body with a chamber and an inlet and an outlet extending therethrough into said chamber, a gate mounted for reciprocation in said chamber between open and closed positions, a pressure responsive actuator having a housing, a piston, a connection to the gate and an actuating stem extending from the housing, a supplemental actuator having a connection to the actuator housing, an operating stem connected to the actuating stem, the operating stem having a shoulder facing in the direction opposite to the direction of closing movement of the gate, roller levers pivotally mounted to be in engagement with the exterior of the operating stem and a spring urging the roller levers into tight engagement with the operating stem, the roller levers pivoting on engagement with the stem shoulder to exert a closing force on the stem.

Abstract: A rotary/linear convertor which comprises a first member may be in the form of a piston (14, 15, 16, 17, 114, 115, 116, 117) and a guide which is preferably in the form of a cylinder (12, 112) the first member being arranged for linear movement within or along the guide and a second member (23, 24, 137) which is adapted for rotational movement. The convertor further includes connecting means operatively connecting the first and second members so that the respective linear or rotational movement of one member causes the respective linear or rotational movement of the other member.

Abstract: A spring operated valve actuator with variable return force includes a compact spring mechanism with a short but very powerful closing characteristic. The energy provided by the spring mechanism is applied during the entire movement of the valve, with varying forces localized according to particular needs. The spring mechanism and a movable piston member are mechanically and drivingly interconnected by a variable reduction mechanism.

Abstract: A hydraulic operating unit for the friction engaging apparatus of a transmission provides a hydraulic operating unit which permits the introduction of a low-pressure working fluid to permit the forceable disengagement of the hydraulic operation unit to work against the fluid which would normally urge the unit into engagement. The effective pressure-receiving area on the releasing side of a hydraulic power servo mechanism is made sufficiently large with respect to the effective pressure-receiving area on the engaging side of the servo mechanism while the piston diameter is kept small in order to save space in the construction of the servo mechanism while at the same time permitting the device to effectively disengage the friction mechanism.

Abstract: A fluid-pressure-operated, three position working cylinder includes a cylindrical housing having a graduated bore formed therein and a movable primary piston dividing the bore into first and second pressure chambers. A movable secondary piston surrounds a portion of the primary piston and moves relative to the primary piston within the limits of a piston stop arrangement formed on opposing surfaces of the pistons. The piston stop arrangement includes an elastic stop on the primary piston which interacts with a sloped stop formed on the secondary piston so that upon initial insertion of the secondary piston onto the primary piston, the sloped stop compresses the elastic stop. The sloped stop includes a lip portion that can contact the elastic stop so as to restrain the secondary piston from further movement in one direction relative to the primary piston. A vent passage formed in the housing allows venting of the space between the two pistons.

Abstract: An actuator including a first cylinder chamber and a second cylinder chamber defined as separate entities in a cylinder for receiving a first piston and a second piston therein respectively. One of the first and second cylinder chambers is connected to an oil pressure source and the other cylinder chamber is connected to an air pressure source. A piston rod of the first piston and a piston rod of the second piston which move in relative sliding movement have at their forward ends separate operating portions for performing operations on a common workpiece.

Abstract: The casing of the jack is divided into two cylinders by a cross partition, with a first piston which moves in one of the cylinders and a second piston, forming two parts, linked by a rod which crosses the partition to its first part which moves in the first cylinder-shaped piston and its second part which moves in the second cylinder of the jack. The fluid is conveyed selectively either to the cylinder formed by the first piston or to the second cylinder which communicates with the first cylinder through holes drilled in the partition.

Abstract: A spring brake actuator for a rail vehicle brake unit, comprising a cylinder and a rod shaped member. The actuator includes a cylinder-shaped housing, a piston with a piston rod and a spring intended to act in a brake applying direction.In order to obtain a truly modular system the actuator, as an integrated and self-contained unit, is arranged on the rod-shaped member of the brake unit. Its housing is attached to the brake unit cylinder. The actuator piston rod is tubular and slidable on the rod-shaped member.

Abstract: A brake actuating mechanism includes a housing defining a cylinder and a tubular piston, slidingly sealed within the cylinder. A pull-rod passes through the piston and is provided at one end with member for connection to a brake linkage mechanism. The other end of pull-rod is provided with abutment member which engages one end of a guide spool, the other end of the guide spool engaging the end of the piston. A pivot member is provided between the guide spool and the piston to permit rocking of the guide spool and pull-rod relative to the piston. A lever mechanism may act on the guide spool to provide for mechanical actuation of the brake.

Abstract: A safety relief system for a valve in a vent or a main flowline. The safety relief system utilizes a main actuator (24) utilized primarily for a positive pressure condition and a vacuum actuator (96) in axial alignment with the main actuator (24) utilized exclusively for a negative pressure condition. The main valve member (18) has a stem (22) which extends within both actuators (24, 96) and diaphragms (26, 100) are connected to the stem (22) for movement of the valve member (18).

Abstract: In a line pressure control device for a hydraulic control system of an automatic transmission, a vacuum diaphram unit is constructed to apply upon a valve spool of a throttle valve or a regulator valve such a force that reduces with increasing intake manifold vacuum when the intake manifold vacuum is lower than a first predetermined value and such a force that increases with increasing intake manifold vacuum when the intake manifold vacuum is higher than a second predetermined value.

Abstract: A material dispensing valve finding particular application in the robotic dispensing of sealants, adhesives, etc. in a desired pattern on a workpiece. The dispensing valve comprises a unique actuating arrangement wherein back to back pancake cylinders are moveably arranged within a housing and, depending upon how the cylinders are actuated, three or four dispense rate positions can be provided. The dispense rate positions of the valve are preferably coordinated with the rate of movement of the robotic system so that the dispense rate is appropriate for the rate of movement.

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: Apparatus for filling containers with two products from different sources, using a rotating volumetric filler which picks up first one product then the other, and discharges them both simultaneously into a container. The filler uses a pair of concentric pistons, the central one of which is retracted to pick up the first product as it rotates over an arcuate slot beneath which the first product is stored; the outer, cylindrical piston is then retracted to pick up the second product as it rotates over another arcuate slot beneath which the second slot is located. Both pistons are later extended simultaneously to discharge the combined product into the container. Since the two products picked up by the successive retractions of the two pistons are held beside each other, a more uniform mixture of the two products is obtained than if they are picked up one above the other by a single piston.

Abstract: A gear positioning cylinder having forward, reverse, and neutral gear selection provided by a positioning rod attached to a main piston in which an auxiliary piston is telescopically arranged for compactness.

Abstract: A piston type pneumatic powered actuator (9) for operating a valve (10) of the expanding gate type wherein velocity of the piston-stem-gate drive train is maintained substantially constant in the latter stage of the actuator stroke. The actuator (9) includes an assembly of dual pistons (61,75) which are adapted to be driven by fluid pressure in one direction to operate the valve but are returned by spring means (66,67) when the fluid pressure is removed. A drive piston (61) directly connected to the actuator stem (23) is nested within a primary piston (75) which is not connected to the actuator stem (23) but moves the drive piston (61) when actuating pneumatic fluid is applied to the actuator (9). A stop (85) affixed to the primary piston (75) is adapted to cooperatively engage the actuator housing (40) to terminate the stroke of the primary piston (75) prior to termination of the stroke of the drive piston (61).