Abstract: A vacuum actuator for connection to a vacuum source, the actuator utilizing a diaphragm combination having three stable positions. An annular diaphragm, having its outer periphery fixed in a housing, has its inner periphery secured between two movable annular members, the diaphragm and the annular members forming a combination dividing the housing into upper and lower chambers. Two inlet ports individually supply a vacuum force or atmospheric pressure to the upper chamber, the first one of the ports including a projection extending toward a space formed by the movable members. A poppet valve normally closes an opening at the top of the space, the bottom of the space normally having access to the atmosphere. When vacuum is applied to the first port, the diaphragm combination is raised from a biased first position to the position where the poppet valve interrupts the vacuum through the projection, determining the second position.

Abstract: An expandable cushion plunger for use with a fluid pressure driven piston and cylinder device includes a cushion sleeve mounted on a piston rod in floating relation thereto, and having a skirt, the interior of which is exposed to the cushioning fluid within the cylinder. As the piston nears the end of its stroke, the sleeve begins to enter a fluid exit port, trapping fluid between the piston and the cylinder head, which will slow and cushion the piston travel as it approaches the cylinder head. As the sleeve continues to enter the fluid exit port, the pressure of the trapped fluid increases due to the smaller size of the annular orifice between the sleeve and the port as compared with the port size. The cushion sleeve may expand under influence of increased pressure, further restricting the flow of pressurized fluid through the annular orifice to provide smooth deceleration of the piston as it reaches the end of its stroke and comes to rest against the cylinder head without undesirable impact.

Abstract: A hydraulic actuator and control for positioning the boom of a backhoe mounted on the rear of a tractor that smoothly decelerates the boom at the limits of its horizontal swinging movement. A directional control valve ports fluid to two double acting hydraulic actuators positioned in opposed relation on the tractor to drive the boom from side to side. The boom is cushioned at the limits of its travel, whether or not the operator releases the operating pedal for the directional control valve, by blocking discharge flow from a contracting actuator to the directional control valve and porting this discharge flow over a pressure relief system that is independent of the directional control valve. The pressure relief system provides substantially constant deceleration of the boom without high peak pressure in the actuator by using a lower pressure relief valve in the actuator cylinder heads arranged in series with a higher pressure relief valve that discharges directly to tank.

Abstract: A vacuum operated servo comprises a vacuum chamber defined by a flexible diaphragm and a cover, a valve seat secured to the cover so as to project into the vacuum chamber, a valve body yieldably mounted on the flexible diaphragm, a first vacuum conduit with a first valve for inducing vacuum from a vacuum source into the vacuum chamber through the valve seat, a second vacuum conduit with a second valve for inducing vacuum from the vacuum source into the vacuum chamber, and a leak orifice for leaking the vacuum in the vacuum chamber. When the first valve is opened to induce vacuum of the vacuum source into the vacuum chamber, by the vacuum, the diaphragm is moved so that the valve body contacts with the valve seat. Upon the contact, the induction of the vacuum is interrupted to stop the movement of the diaphragm, with the vacuum being introduced and leaked out of the vacuum chamber.

Abstract: An automotive type carburetor has a rotatable lever connected to the choke valve and to an actuating link having a pin-slot type connection to an engine vacuum controlled servo, a fast idle cam is connected to the choke lever by a lost motion pin and slot connection and to a second actuating link also connected to the servo by a pin-slot type connection, the servo pin-slot connections to the links are such that when the engine is started with the choke valve closed and the fast idle cam on its high cam step, vacuum applied to the servo during a first stage movement rotates the choke lever to open the choke valve and subsequently during a second stage movement both the choke lever is rotated further and the fast idle cam is rotated off its fast idle step position, to reduce the opening of the throttle valve while opening further the choke valve, the first stage movement of the servo moving a diaphragm and plunger until the plunger blocks a main vacuum feed line to the diaphragm, the second stage movement movin

Abstract: The invention relates to a cushioning device for a piston of a pneumatically operable driving tool which includes a cylinder, wherein a drive piston connected to a driver blade is axially movable; including further a bumper at the lower end of the cylinder and an annular chamber connected to a fluid power reservoir; this chamber is located underneath the piston and is surrounding the driver blade. The annular chamber, created by the piston and a wall, generally parallel to the face of the piston, will be reduced in volume to a certain extent when the wall impacts on the bumper to reduce the noise generated during the driving action.

Abstract: A piston, especially for a pneumatic cylinder, includes a disc-shaped piston head and a sealing element on the head, such element has at least one annular sealing lip extending outwardly of the peripheral sliding surface of the head, the sealing lip being of elastic and resilient material and being of conical form relative to a central axis of the piston head, an outer free edge of the lip thereby being capable of sealingly engaging the wall of the cylinder.

Abstract: A fluid motor or vacuum break for use with the carburetor of an internal combustion engine in which an output plunger of the motor moves in two stages and at different rates in each of the stages through means of an auxiliary housing supported within the main housing. Upon admission of vacuum pressure to the primary housing and output plunger moves in a first stage at the end of which vacuum pressure is admitted to the auxiliary housing causing it to collapse and move the plunger in a second stage.

Abstract: A piston cylinder assembly includes a piston rod reciprocatively mounted within a piston chamber, and a piston fixed to the rod within the chamber. A pair of pots are mounted on opposite ends of the cylinder chamber in fluid communication therewith, each one of the ports having a laterally extending portion adapted to be connected in fluid communication with a source of fluid under pressure and having an axially extending portion opening into the interior of the chamber. A tapered seal is mounted on one of the end portions of the piston for sealing the axial portion of one of the ports to provide a cushioned movement of the piston at the terminal end of its stroke. A sleeve member extends axially within the last-mentioned axial portion of the port and terminates at one of its ends at a position disposed opposite the lateral portion of the port. A bleeding device permits fluid to leave the chamber as the seal engages sealingly the sleeve member so that the terminal portion of the piston stroke is cushioned.

Abstract: This invention is directed to fluid actuated apparatus for automatically restricting the flow of fluid in conduits leading to and/or from fluid actuated cylinder means for causing pivotal movement of a member, such as the turret carrying the boom and bucket of a backhoe, so that the speed of pivotal movement of the member is rapid during one portion of its pivotal movement but is automatically reduced during a predetermined portion of its subsequent pivotal movement, thereby minimizing failures of the components of the member and the fluid system and improving the braking action for reducing the speed of pivotal movement of the member. In one embodiment, both the flow of fluid to the operative fluid actuated cylinder and the flow of fluid from the inoperative fluid actuated cylinder are restricted substantially simultaneously by fluid restricting means so that the linear velocities of the rods of both cylinders are reduced substantially simultaneously by the fluid restricting means.

Abstract: A spring device including a piston slidably disposed in an inner cylinder of a dual inner and outer cylinder with a piston rod secured thereto and extending to the outside of the cylinder through a rod guide closing one end of the inner cylinder, an oil passage formed in the rod guide and connecting an annular chamber between the inner and outer cylinders with the interior of the inner cylinder, and a device for supplying a force on the piston to project the piston rod outwardly, in which a guide member is supported on the piston rod with a coil spring interposed between the guide member and the piston, and the guide member is adapted to contact the rod guide to control the oil flowing through the oil passage when the piston rod moves outward by a predetermined amount.

Abstract: A piston of a hydraulic actuator is threaded on one end of a piston rod and is prevented from becoming unthreaded therefrom by means of a radially extending key received in a keyway formed by cooperating recesses in the ends of the piston and piston rod. A threaded fastener extends axially into the piston rod and holds the key in place.

Abstract: Cushioning means for cushioning the end portion of the stroke of a piston in a cylinder comprising a stepped cushioning member or spear which enters a cylinder head bore to form therewith an annular orifice which successively decreases in area and gradually increases in radial width from one step to the next thus to decrease piston velocity at substantially uniform rate and, hence, at substantially constant deceleration with substantially constant pressure drop across the annular orifice.

Abstract: An improved spring controlled poppet-type cushion for a fluid piston-cylinder device, wherein the cushion is connected to the piston by spring means and aligned with the inlet-exhaust opening at the end of the cylinder. The improved cushion includes retaining structure for holding the spring associated with it in axial alignment with the opening for receipt therein as the piston approaches the end of the cylinder. This permits the piston to move into contact with the wall without interference from the spring. The sealing of the cushion within the opening in the end of the cylinder is effected at a point spaced axially from the piston when the latter is in contact with the end wall to provide an axial spacing between the cushion and piston.

Abstract: The piston of a fluid ram is provided with an end of stroke braking means comprisng a pusher adapted to contact the end wall of the ram cylinder as the piston approaches the end wall to restrict the flow of fluid from the outlet chamber of the ram to an outlet part. As the ram moves nearer the end the pusher opens a valve in the piston to connect the inlet chamber of the ram to the outlet part.

Abstract: Cushioning means for cushioning the end portion of the stroke of a piston in a cylinder comprising a stepped cylindrical member which enters a cylinder head bore to form therewith an annular orifice which successively decreases in area and increases in length thus to decrease piston velocity at substantially uniform rate and, hence, at substantially constant deceleration with substantially constant pressure drop across the annular orifice.