A variable displacement pump having a tiltable swash plate including a pair of servo mechanisms for controlling discharge of pump fluid includes a zero displacement positioner for automatically returning the pump swash plate to a central, neutral position to discontinue pumping action if pump pressure is lost or if linkage controlling one of the servo mechanisms should break or otherwise fail.

The invention relates to a method and an apparatus for straightening the pins of semi-conductor devices such as transistors and the like. The apparatus includes means for holding the head of a semi-conductor device, means for preventing the pins thereof from separating from one another beyond a cylindrical volume defined by the outer diameter of the ring formed by the pins where they join the head and a plurality of pistons in one to one relation with the plurality of pins generally perpendicula...

A closed center control valve for double acting motors having an inlet passage and a pair of control passages is provided with pre-sized restrictions in the control passages to control the flow rate to the motor so that a pre-selected velocity of movement of the motor is achieved.

A welding gun is provided having vacuum fume extraction means wherein the level of vacuum exerted at the arc welding zone is regulated to avoid extracting shielding gas supplied to the welding zone. The vacuum level is regulated by admitting sufficient air to a fume extracting passage provided within the gun to reduce the vacuum to the desired level.

A shock absorbing cab mounting device for a vehicle is disclosed, comprised of a flange member fixed to the vehicle frame and an elastomeric vibration absorbing device, the flange member having a projection extending upwardly and inwardly with an axial bore centrally located in the top portion. The projection is bondingly surrounded by an elastomeric member which has embedded therein and interior of the projection a fastening nut, the fastening nut axially aligned with a bore in the elastomeric ...

A clutch for coupling an engine to a transmission gearbox engages and disengages automatically in response to engine speed variation. Springs hold the clutch pressure plate retracted from the clutch discs at idling speeds. As engine speed increases, centrifugally generated fluid pressure in the clutch lubricant overcomes the spring force and applies a modulated engagement pressure to the discs. An internal valve continuously supplies an oil flow to lubricate and cool the clutch components and to...

A bulldozer assembly comprises a pair of laterally spaced push arms pivotally interconnected between a blade thereof and a vehicle. A pair of lift cylinders are also pivotally connected between the vehicle and the blade for selectively raising or lowering the blade relative to the vehicle. A tilt mechanism for selectively tilting the normally upright blade in a vertical plane comprises first and second members each pivotally interconnected between the vehicle and the blade on an outboard side th...

A drive train for vehicles such as earthmoving machines having a prime mover coupled in driving relation with ground wheels for the machine through a power input member and a power output member. One or more implements are coupled to the power input member. In order to selectively match or mismatch power delivered by the prime mover with varying power requirements for the implements and wheels, a hydraulically operated slipping clutch is arranged between the power input and output members for ad...

A hydraulic circuit is provided for powering and controlling an excavator or the like, with a plurality of pumps supplying pressurized fluid for the circuit. The circuit is arranged so that fluid is provided in a manner to permit positive independent control of the various implement motors of the machine, with means provided so that fluid may also be combined to operate selected implement motors for faster operation and maximum efficiency of the machine.

A reversible warehouse wagon is provided with a jointed bed, tandem-mounted center support wheels, steerable wheels supporting both the ends of the bed and hitch means at both ends of the bed to provide a warehouse wagon that is towable from either end having a short turning radius, high directional stability, improved tracking of a towing vehicle and improved support and control for going up and down ramps.