Abstract: An electric-hydraulic pulse motor having an improved rotary guide valve means is provided. In the rotary guide valve, a valve member for controlling the supply of fluid to the hydraulic motor is adapted to be shifted for performing the controlling function by the effect of pressurized fluid. The valve member is supported on a valve shaft or a signal input shaft which is to be actuated by a conventional electric pulse motor or the like so that the valve member rotates with one of the two shafts but is allowed to be shifted transversely thereto to either of two eccentric positions by the effect of the pressurized fluid. Control for shifting the valve member is obtained by arranging the two shafts so that the relative movement between the two shafts controls the pressurized fluid so as to move the valve member to the desired one of the eccentric positions.

Abstract: An electronic system to monitor the performance of a pneumatic impact forming tool is disclosed. A signal is generated in real time representing the actuating pressure of the pneumatic tool. Electronic functions operate on the real time pressure signal over a predetermined time portion of each work cycle of the pneumatic tool to generate signals representative of the energy and friction developed in the pneumatic tool during the predetermined time portions of one or more work cycles. The electronic system additionally provides a count of the number of work cycles generated by the pneumatic tool during operation thereof.

Abstract: An electro hydraulic system for controlling a hydraulic function includes a pump and a reservoir connected to the function through a manually operable, electro-hydraulic control valve. The valve is positionable to either side of a neutral ports blocked position and may be held to one side by the engaging of a spring loaded detent. The detent is disengaged by an electrical signal produced by a comparator when a preset, operator-controlled, limiting signal is equalled by a feed back sensor signal proportional to the output of the function. The system will allow initial activation of the valve to provide continuous operation of the function until the limiting input is reached at which time the function will be stopped. The system further provides manual override of the electrical control system to permit operation of the valve when the feedback signal is greater than the limiting input signal.

Abstract: An injection-molding machine has a drive ram with a pressurizable chamber that can be connected either to the high-pressure side or the low-pressure side of a source of fluid under pressure. A control system operating this machine has a pressure-reducing valve with an inlet port connected to the high-pressure side of the source, an outlet port connected through a cut-off valve and a throttle to the chamber of the ram, and a pilot port pressurizable to control the pressure at this outlet port. A pressure-relief valve has an inlet port connected to the pressurizable ram chamber, an outlet port connected to the low-pressure side of the pressure source, and a pilot port pressurizable to control the pressure differential across this pressure-relief valve.

Abstract: The invention relates to a servo assembly having a stationary part including a housing, a movable member and a servo motor. Of primary interest is the stopping mechanism which includes a stop unit on the movable member and two pressure operated, vertically reciprocal stop members mounted in the housing. Two hydraulic circuits are provided with a first circuit for the two stop members and the second circuit for the servo motor. Throttle valving for the first circuit is provided between the two stop members and the housing. Prior to reaching a stopping position the stop unit on the movable member actuates a switch which relieves the pressure in the first circuit and causes one of the stop members to descend to an intermediate position where throttling occurs and the other stop member to descend to a final position where throttling may or may not occur. The throttling causes substantial braking of the movable member during a short distance of travel just prior to the stopping position being reached.

Abstract: In a mineral mining installation employing a series of shifting rams for advancing a scraper-chain conveyor provided with a guide for a mining machine a control system with a central control station for transmitting control signals. The control signals serve to actuate local control valves, possibly in time dependence, to cause a selected one or group of metering devices to transfer a pre-determined volume of pressure fluid to one or more of the rams to effect said advancement. This volume of pressure fluid is some fraction of the total capacity of the ram or rams in question so that by repeatedly transmitting control signals the device or devices can perform successive cycles of operation to thereby cause the ram or rams associated therewith to extend in defined increments.

Abstract: In a positive-displacement hydraulic motor a valve is mounted so as to be moved positively, individually and continuously during the operation of the hydraulic motor. Spacings between adjacent pairs of valve ports, variable volume chambers and cam portions of the guide element are selected from a predetermined relationships. Such an arrangement makes it possible to predetermine the mode of operation for the hydraulic motor by selecting previously the speed of the movement of the valve.