Abstract: A pneumatic positioner with a casing composed of a shell-like bottom part and a shell-like cover part. A membrane plate, is connected through a gas-tight membrane with the side walls of the casing so as to be movable back and forth in the casing in the direction of a drive spindle which is disposed in sealing relationship through the bottom part of the casing. In the bottom part and/or in the cover part, there are arranged one or more gas-conducting connecting pieces. In the casing there are arranged coil springs for producing biasing or restoring forces. These springs abut, on the one hand, the membrane plate and, on the other hand, the bottom part or cover part. On the membrane plate of one embodiment there is provided for each coil spring at least two supporting surfaces which present different spacings from a plane perpendicular to the direction of motion of the drive spindle and upon which the coil springs are replaceably disposed.

Abstract: Ceramic coatings prevent metal to metal contact between double acting pistons and cylinders. Cylinders and pistons operate in true cylindrical form. Ceramic coated cylinders are gradually brought to operating temperatures while temporary cutting pistons shape the coating to a true cylinder at operating temperature. Cylinders are formed true while cold and cylinders and heads are jacketed with high heat flow conductors so that the cylinders and cylinder heads have uniform operating temperature.

Abstract: A friction-welding machine of the type in which a cylinder arrangement applies pressure to urge two workpieces together upon the rotation of one of the workpieces against the other to prepare the interface for bonding. The cylinder arrangement which applies the welding pressure comprises a main cylinder whose piston acts upon the workpiece through a head formed with an auxiliary cylinder and piston arrangement greatly increasing the working range of the cylinder arrangement.

Abstract: A pressure-medium connection between a valve block and a load which has at least one double-acting pressure-medium motor. The valve block and load each have two connecting openings for supplying the pressure-medium motor. An interposed sealing plate has through openings in the form of channels which extend in the plane of such sealing plate for connecting the resepctive openings of the valve block housing and load housing. The connecting openings of the valve block housing are offset with respect to the connecting openings of the load housing. In a first operating position of the sealing plate, the control channels therein connect the first connecting openings of the valve block housing and load housing and also connect the second connecting openings of the valve block housing and load housing.

Abstract: A bimodal, non-venting pneumatic relay senses the presence or absence of a first pressurized fluid and controls the supply or temination of a second pressurized fluid to associated equipment. The relay includes a segmented housing defining plural grooves which accept annular seals, a valve stem against which the seals seat and a reversible piston. The reversible piston can be selectively oriented and installed to provide either, manual rest operation to interrupt the supply of the second fluid if the first fluid supply is interrupted, the relay requiring manual resetting to reestablish supply of the second fluid, or automatic reset operation, wherein restoration of the second fluid supply is achieved automatically if the first fluid pressure is re-established subsequent to an interruption.

Abstract: A piston mechanism for sensing a control fluid pressure and shifting a valve element in response thereto. The piston mechanism comprises a first piston having an internal bore in which is positioned a second piston. Varying ranges of fluid pressure sufficient to actuate the piston mechanism are accomplished by positioning the piston mechanism within its piston chamber in varying orientations so that the effective piston surface area exposed to a control fluid is dictated by the specific orientation of the piston mechanism within the chamber. In one orientation, the effective fluid pressure surface area is that of the larger piston member. In a second orientation, the effective surface area exposed to the sensing fluid is a first surface of the smaller piston carried by the larger piston. In a third orientation, the effective surface area exposed to the sensing fluid is that of the opposite end of the second piston.

Abstract: An arrangement for modifying a plow blade power unit of the type positioned between the mounting frame on the front of a vehicle and a plow blade lift arm, to a unit for creating pressurized fluid from a remote location. Modification enables a basically similar power unit to be utilized in both remote and direct operational environments with only minor substitution of interchangable parts. A piston-cylinder unit which enables direct lifting of a plow blade is replaced by a modified, but similar, cylindrical element for use in indirect lifting of a plow blade by fluid under pressure.

Abstract: A fluid pressure cylinder which utilizes a standardized housing, piston and piston rod for forming a cylinder assembly either with or without bumpers. The bumpers can optionally be positioned on the piston when desired, with the overall assembled length and maximum stroke of the cylinder being identical whether provided with or without bumpers. The piston is selectively mounted on the piston rod in one axial orientation if bumpers are not used, and the piston is reversed and mounted on the piston rod in the opposite axial orientation when bumpers are used.

Abstract: Apparatus for fixing and driving a displacement member (such as a wheel) of a vehicle is disclosed. In particular, an axle journal is coupled to the vehicle chassis. At least one rotating bearing surface is disposed between the displacement member and the axle journal for the rotatable assembly of the displacement member. A drive motor is provided having a stator which is removably attached to the axle journal and a rotor which is removably mounted to rotate with respect to the stator by means of rotating bearings in contact with the bearing surface. Since the rotating bearings of the motor only contact the removable bearing surface, the motor can be dismantled while maintaining the displacement member in place on the axle journal.

Abstract: A dashpot wherein a fitting including a calibrated bleed orifice formed therein is detachably retained in a valve body which houses a check valve and forms a part of a diaphragm chamber.

Abstract: An actuator, in which fluid pressure on a piston advances a stem against retractive force provided by a spring, a hydraulic dashpot is provided for the stem, and a stroke varying cushion is used for preventing engagement of a back seat between the stem and housing except when a seal is desired.

Abstract: A power cylinder of the multiple stage telescoping type that is characterized by a plurality of telescoping piston and cylinder assemblies, each of which comprises a composite cylinder and piston sleeve construction and an end closure construction that provides an extension stop for the piston sleeve of the next adjacent stage. The apparatus is further characterized by a quickly detachable base plate construction which permits ready access to the interior components of the cylinder via the base end thereof.