Abstract: A reversible double-throw air motor provides for forward and reverse operation by having a cylinder member rotate relative to a stationary valve plate between fixed forward and reverse positions of the cylinder member. The valve plate has diametrically opposite pressure ports and diametrically opposite exhaust ports at an end surface that faces the cylinder member. The cylinder member has a transfer passage associated with each quadrant of the inner surface, the transfer passages opening at wall ports at the inner surface close to each of the two bottom dead center lines. In the forward position of the cylinder, pressure is supplied from the pressure ports in the valve plate through two of the transfer passages to opposite quadrants while the other two quadrants are open to the exhaust ports in the valve plate. For reverse operation, the cylinder is rotated, which reverses the quadrants open to the pressure and exhaust paths.

Abstract: A reversible double-throw air motor provides for forward and reverse operation by having a cylinder member rotate relative to a stationary valve plate between fixed forward and reverse positions of the cylinder member. The valve plate has diametrically opposite pressure ports and diametrically opposite exhaust ports at an end surface that faces the cylinder member. The cylinder member has a transfer passage associated with each quadrant of the inner surface, the transfer passages opening at wall ports at the inner surface close to each of the two bottom dead center lines. In the forward position of the cylinder, pressure is supplied from the pressure ports in the valve plate through two of the transfer passages to opposite quadrants while the other two quadrants are open to the exhaust ports in the valve plate. For reverse operation, the cylinder is rotated, which reverses the quadrants open to the pressure and exhaust paths.

Abstract: An impulse tool (10) including an impulse generator (19, 119) utilizes an enhanced seal to reduce leakage of hydraulic fluid. The annular clearance in the pressure plate (24, 124) is sealed around the spindle (30, 130) with a resilient seal (38, 138). A primary passage (40, 140) through the pressure plate is provided to compensate for expansion of the fluid. The use of the primary passage (40, 140), which is not susceptible to enlargement due to wear, minimizes pressure peaks in the accumulator reservoir (42, 142), and results in less leakage.

Abstract: An impulse tool (20) having a housing (22), a motor (26), drive mechanism (30), impulse mechanism (28), trigger mechanism (67), and sensor (32) for automatic shut-off is disclosed. The sensor (32) uses a spring-biased ball (144) that sits on a ball seat (149) adjacent an entry orifice (108) and a spring-biased piston (112) such that when a predetermined non-transient torque is reached, the strength, duration and frequency of pulses of the working fluid entering the entry orifice (108) will lift the ball (144) sufficiently to impose on the piston (112) and to progressively lift the piston (112) to allow the working fluid to a triggering height which starts the shut-off of the impulse tool (20). A delay mechanism is also disclosed that may include a regulator (172), dashpot (170), spring latch (204), and trigger bar (56) or latch. A method of cooling an impulse tool with cold, dense air throughout is also disclosed.

Abstract: An impulse unit (10) is disclosed which provides for a symmetric transfer of torque between a case (16) and spindle (18) selectively for one or two impulses for each relative rotation between the case and spindle. A pair of cylindrical rollers (84, 86) is provided to isolate two symmetric chambers between the case and spindle to transfer torque therebetween. The use of cylindrical rollers reduces the overall wear in the tool, improves oil sealing capability during long time use, and reduces the cost of manufacture.

Abstract: A power drill system the type having a positive drive spindle incorporating an adjustable depth control means mounted on the spindle. The depth control means includes a collar having an internal bore which is provided with threads conforming to the spindle threads. Thus, the collar may be longitudinally adjusted to a desired position on the spindle by rotating the collar relative to the spindle. The collar is provided with a plurality of circumferentially spaced detent chambers. A detent member is secured in at least one of the detent chambers and extends into at least one of the spindle grooves in order to key the collar against rotation relative to the spindle and thus fix the collar at the desired longitudinal location. A thrust bearing assembly is secured to the collar in interposition between the collar and the stop shoulder. Upon contact of the depth sensing means with the stop shoulder, the thrust bearing assembly permits relative rotational movement between the collar and the stop shoulder.

Abstract: The invention provides a low pressure shut off device contained within a pneumatic tool that senses the air pressure of an air stream supplied to a pneumatic motor and shuts off the air flow when the pressure falls below a predetermined level set to maintain consistent performance of the tool and to avoid damage to the tool or to the workpiece. The invention includes a throttle valve, a throttle piston that moves to open and close the valve, and a device for sensing the air pressure of the supply stream, holding the throttle valve open when the pressure is sufficient and closing it when the supply pressure is insufficient. The invention may also be used in combination with an air control system within a pneumatic tool such that the sensing device shuts off the flow of air to the air control system as well as the motor when the air control system pressure is insufficient.

Abstract: The invention relates to a torque-limiting clutch for use in combination with a positive feed drill that has a reversible motor and reversible driving means. A preferred use of the clutch is in combination with a drill that has a reversible motor rapid advance system. The clutch provides direct drive in a forward mode and is torque-limiting in a reverse mode so as to protect the gears from breaking due to excessive torque while the gears are turning in reverse during the rapid advance mode. In the reverse mode, the torque-limiting clutch protects the drill bit as it bears on the workpiece and prevents unscrewing of the drilling and mounting components. In a preferred embodiment the clutch is mounted on a shaft and is comprised of two clutch jaws that drive through lugs mounted on the jaws. The lugs provide direct drive in a forward rotation, but are shaped so as to allow the jaws to disengage when the torque is excessive in a reverse rotation.

Abstract: The invention provides a radial vane motor with springs for forcing the vanes radially outward from the rotor. The rotor is eccentrically mounted within a cylindrical cavity in the motor. The vanes extend radially outward from radial slots in the rotor and contact the inner wall of the cavity. Each vane has a spring and a push rod for biasing the vane radially outward against the cylinder wall. Each spring is disposed in a spring chamber positioned diametrically opposite one of the radial slots. Each push rod includes a flyweight disposed within the spring chamber. The spring acts on the flyweight to urge the push rod against the vane during start up and slow speed operation of the motor. When the rotor is rotating at normal speed, centrifugal force acts to urge the vanes radially outward and to deactivate the springs by forcing the flyweight radially opposite the vanes to compress the springs. Thus, the springs are protected from continual flexing by the vanes as the rotor rotates.

Abstract: The invention relates to a reversible radial vane air motor with manual speed control that is capable of attaining excellent forward horsepower. The invention includes a bypass air passage and an exhaust deflector that routes pressurized air through the backside of the motor when the motor is operated in reverse. A reverse control lever controls the flow of air through the bypass passage and opens a reverse exhaust passage. The motor may also be equipped with a centrifugal governor for controlling the flow of air in the forward operation with the governor being bypassed in reverse operation.

Abstract: A rotary pneumatic tool includes an over-speed shut-off mechanism including a shiftable spring washer and flyweights for imparting a shifting force to the spring washer dependent on the speed of the tool. In the preferred embodiment, the spring washer is shifted by spherical balls restrained by cylindrical walls within a body affixed to the rotor in combination with the spring washer and spring members attached to the body. The spring rates of the spring washer and spring members predetermine the speed at which the over-speed mechanism becomes activated.

Abstract: An improved right angle drill including a pneumatically powered motor and feed and retract apparatus driven by the motor. The feed and retract apparatus includes a control valve for controlling the flow of pressurized air to the motor and to the feed and retract apparatus to automatically stop the feed motion, to automatically stop the retract motion, and to stop the drill completely.

Abstract: An improved flow control valve apparatus for pneumatically powered tools that include a motor and feed and retract apparatus driven by the motor. The control valve apparatus includes a main flow valve and a retract control valve each of which is controlled by the control valve to provide air to the motor, to automatically stop the feed and retract motion of the tool, and to stop the tool completely when desired.

Abstract: The improved dwell and depth attachment includes an elongate housing that is attached to a drill motor and has an output shaft that is movable longitudinally and rotatably in the housing for rotating a drill bit. A drive spindle is connected with the output shaft and extends through the housing. An elongated sleeve encircles the spindle and has an end that is engageable with the work piece. An adjustable depth control located within the housing is connected for movement with the spindle. A first portion of the control includes a threaded interior and has ten circumferentially spaced, radially extending holes therein. The control also includes a second portion that has a threaded exterior mating with the first portion and has ten slots equally spaced about the exterior. A stop screw or the like is removably located in one of the radial extending holes in engagement with the second portion.

Abstract: The improved power tool includes a housing having a motor located in the housing and a rotatable tool drive shaft projecting from the housing. A torque reaction bar is attached to the housing and is engageable with a stationary object to prevent rotation of the housing relative to a threaded fastener or the like being operated upon. A tool handle rotatably encircles the housing permitting the positioning of the handle in any desired position relative to the housing and, due to the swivel or pivoting relationship, preventing the imposition of torque on the handle.