Abstract: A hand-held power screwdriver or like tool includes a spindle which is adapted to receive and retain tool bits for rotation thereon. A collet ring is retained with a recess on the housing for slidable movement along the spindle axis. The collet functions as a selectable spindle locking device whereby the tool may be operated as a manual screwdriver or the like by selectively positioning the collet to rigidly lock the spindle in fixed relationship to the tool housing.

Abstract: A device for driving a drilling and/or impacting tool including a shaft journalled in a housing so as to be rotatable, if necessary. One end of the shaft is connectable with the tool whereas the other end is accessible for an oscillatory impact body movable in the housing by a guide, a rotatable driving shaft setting and a transmission. The transmission includes a device for converting the rotary movement of the driving shaft into an oscillatory movement of a driving element which is connected through an elastic member with the impact body.

Abstract: A reversing switch for use in a rechargeable hand tool, the switch being located between the battery and the electric motor and being in direct contact with both. The switch has an actuator pivotally connected to an insulating mounting support which also holds two transfer terminals, one connected to each of two terminals of the battery, and a contact carrier which is rotatably connected to the support and coupled to the actuator in order to be rotated by the pivoting of the actuator. Pivot contacts are attached to the contact carrier displaced from one another to provide a space for the parallel leads of the electric motor. Pivoting of the actuator reverses the connection of battery terminals to the motor leads and, accordingly, reverses the direction of the electric motor. The transfer terminals have recharging contacts which are accessible through ports in the housing of the hand tool to allow recharging of the battery without removing it from the rest of the tool.

Abstract: A surface sander having a housing with a handle and a motor with a motor shaft arranged in a bearing of a sanding foot which is connected through a flexible body with the housing, is disclosed. A dust hood encloses the motor, the housing, the flexible body and the sanding foot. Two parts of the hood are mutually lockable, and the flexible body has an upper annular rim which can be clamped between a bottom rim of the motor housing and the dust hood parts. A lower annular rim is fastened to the sanding foot and a number of spring strips connects the upper annular rim to the lower annular rim, so that the sanding foot can be mounted on the machine in a simple manner by the dust hood without the need for additional fastening devices.

Abstract: A reciprocating jigsaw tool having a plurality of selectible fixed linear plunger and blade motions as well as fully adjustable orbital and manual or auto scrolling saw blade control. A single mode selector is provided to select between the above operational modes. The mode selector includes a cam to selectively limit the oscillatory motion of a pivotally mounted plunger upper swivel bearing carriage assembly thereby directly limiting the degree of orbital plunger motion. The mode selector further includes a gear segment in operative engagement with a rack member which, in turn, engages an integral scrolling interface member of the top-mounted scrolling adjustment knob. The scrolling interface member incorporates an annular ring having a gap therein adapted to inhibit upward travel of the rack which, in turn, inhibits orbital saw operation when the plunger and blade is positioned other than in the cut forwardly position.

Abstract: The invention relates to a fast charge circuit suitable for use with battery cells which can be charged at a 4C rate. Line voltage is transformed, full wave rectified and applied to the battery pack. A pair of voltage comparators monitor a sensing voltage which is indicative of the charging voltage and the trough voltage of the battery cells. During a "window" when the sensing voltage is less than a predetermined threshold and through voltage exceeds this threshold, the comparators indicate that charging should be terminated. Alternatively, if excessive temperature on the cells is detected or a selected amount of time passes without reaching full charge, fast charging is also terminated. After the fast charging interval trickle charging of the cells is employed to bring the battery pack to full charge and maintain it there.

Abstract: Brush holder assemblies are disclosed which prevent the spring, or conductor and terminal connector from protruding out of the brush holder and damaging the motor commutator. The constructions employ a brush housing having a restraining bridge at the front end thereof and a terminal connector having a rearwardly extending flange. As the brush wears down, it and the terminal connector to which it is attached move forwardly in the brush housing under bias of a coil spring. Upon striking the restraining bridge the terminal connector pivots forwardly under tension of the spring thereby wedging the flange against the top of the housing preventing further movement of the brush assembly.

Abstract: A battery charging circuit is operable for recharging batteries in both trickle and fast charge modes. The fast charge mode is initiated and maintained by enabling a silicon controlled rectifier in circuit between a current source and the battery. A capacitor maintains the SCR in the operative state until the battery reaches full charge. A thermostatically controlled switch terminates the fast charge mode. The battery is then trickle charged for an indefinite period. Reversion to the fast charge mode is prevented by discharging the capacitor associated with the SCR when the thermostatically controlled switch opens.

Abstract: A double pole, trigger actuated switch employs a bridge contact and a separate contactor for opening and closing both lines from a source of current to an associated power tool. The bridge contact is always closed first and opened last with respect to the contactor so that the former is not subjected to arcing and may be made smaller and less expensively than the latter. The contactor is of the fast closing type constructed to minimize arcing. A speed control circuit is associated with the contactor. The entire switch, including the speed control circuit, is provided in a compact housing for mounting in small portable hand tools such as electric drills. A heat sink is exposed to the ambient air by virtue of louvers in the switch housing.

Abstract: An apparatus such as a belt sander including spaced apart rolls and adjustable mounting means for supporting at least one roll. An endless belt is positioned around the rolls and drive means are provided for the rolls and belt. Alignment means including a belt edge engaging means are operatively connected to the roll mounting means, and a resilient force is applied to hold the engaging means against a belt edge as the belt is moved by the drive means. This causes the engaging means to follow variations in the belt edge position, and this movement is transmitted to the mounting means whereby the variations are compensated.