Abstract: The present application disclose a wheel blank positioning end face correction device, comprising a frame, a servo motor I, a support frame, a bearing seat, a bearing, a shaft, a rotating platform, a guide rail, a cylinder, a left slide plate, a left bearing seat, a left shaft, a left bearing, a left driven grooved friction wheel, a left workbench, corner cylinder pressure claws, mandrel seats, mandrels, a grinding wheel, a grinding wheel drive motor, a support plate, a feeding slide plate, feeding guide rails, a linear motor, a distance measuring sensor, a fixed plate, a servo motor II, a driving grooved friction wheel, a right workbench, a right driven grooved friction wheel, a right shaft, a gear rack structure and a right slide plate.

Abstract: A method, system, and computer readable medium containing programming for handling fully authenticated transmission of video or other data (content) from a provider to a recipient device via an intermediary device. An inner envelope containing the content and/or security features is prepared and digitally signed using a private cryptographic key. The signed inner envelope is then included in a second, outer envelope which may also include some or all of the content. The outer envelope is also digitally signed, thereby forming a data package which may be sent from the provider to the intermediary device. If the signature of the outer envelope is authenticated at the intermediary device, then the inner envelope is sent to the recipient device which then uses the inner signature to verify its authenticity. Authenticated content may then be presented or otherwise used at the recipient device.

Abstract: A power tool may include an electronically commutated motor such as, for example, a brushless DC permanent magnet motor with a rotor having internally mounted magnets and/or cavities filled with air or other non-magnetic materials. A control system may be used to control the motor in a manner that implements field weakening when the speed of the motor increases beyond its rated motor speed, or when the torque demands on the motor continue to increase after the maximum power output of the motor is reached. The field weakening may offset the growing back EMF and may enable a constant power and constant efficiency to be achieved by the motor over a wide speed range, rather than at just a single predetermined operating speed. Pulse width modulation control of the motor may be used up until the motor reaches its maximum power output.

Abstract: The invention relates to a rock drill air leg control system incorporated in the backhead (10) of a rock drill. The system comprises a single spool valve (22) having two manual controls (46, 53), one for setting a trust applied by an air leg to a rock drill and the other for retracting the air leg without affecting the thrust setting achieved by operation of the first control. The first manual control is in the form of a twist-grip control (53) which is arranged to set the axial position of a spring-biased valve spool (30) in the valve (22) via a pin (50) and a plunger (46). The plunger (46) also forms the second of the manual controls and can be pressed against the spring-biased valve spool (30) to vary the axial position of this spool.

Abstract: A hand held power assisted shears has a piston located in a cylinder formed in a pistol grip body. A trigger controls the position of a hollow shuttle spool rod which slides longitudinally within a hollow piston rod connected between the piston and the blades. The hollow shuttle spool rod carries pressurized working fluid to the piston where it is directed to the space above or below the piston. The piston drives the blades through the piston rod to a position corresponding to the position of the trigger allowing the operator to continuously control the position of the blades and the extent and rate of closure during cutting. The relative position of the shuttle spool rod and the piston rod controls whether the working fluid is directed above or below the piston to open or close the blades. One end of the shuttle spool rod acts as a piston which causes the blades to open automatically when the trigger is released.

Abstract: A hydraulic drilling outfit has a hydraulically driven hammer drill which is fastened pivotally to a hydraulic thrust unit. A control for the hydraulics utilizes the flushing water for the drill bit as the power-source for all of the motions executed by the drilling outfit. One hydraulic supply line to the control of the thrust unit and one line from the control to the hammer drill are sufficient for operating the system in an open circuit. A rotary slide valve simultaneously controls the thrust and withdrawal motions as well as the operational states of drilling and not drilling. The desired value adjustment for the speed of thrust is arranged on the rotary slide valve.

Abstract: Equipment for drilling holes in mine roofs for the purpose of rock bolting comprises an intermediate portion having mounted on and extending from it at one end a telescopic leg and mounted on and extending from it at the other end a drill rod, a hydraulic motor mounted on the intermediate portion and coupled to the drill rod, first valve means adapted to be connected to a pressure fluid source for supplying pressure fluid to the leg for extending it or for releasing fluid from the leg, second valve means adapted to be connected to a pressure source for supplying pressure fluid to the hydraulic motor for driving it or for releasing fluid from the motor and means for controlling the first and second valve means.

Abstract: Equipment for drilling holes in mine roofs for the purpose of rock bolting comprises an intermediate portion having mounted on and extending from it at one end a telescopic leg and mounted on and extending from it at the other end a drill rod, a hydraulic motor mounted on the intermediate portion and coupled to the drill rod, first valve means adapted to be connected to a pressure fluid source for supplying pressure fluid to the leg for extending it or for releasing fluid from the leg, second valve means adapted to be connected to a pressure source for supplying pressure fluid to the hydraulic motor for driving it or for releasing fluid from the motor and means for controlling the first and second valve means.