Abstract: A femoral nail which can be implanted in a bone has a transverse hole, and an arrangement is provided for generating a magnetic field which has a maximum strength along an axis of the transverse hole and which decreases in strength in directions radially away from the axis. A drill guide for axially aligning a drill with the transverse hole has an axial drill opening through it, and first and second sensor arrangements are provided at axially spaced locations on the drill guide and each have a plurality of sensors which are at angularly spaced locations and are spaced radially from the opening through the drill guide. An arrangement responsive to the first and second sensor arrangements detects a deviation of the drill opening in the drill guide from coaxial alignment with the axis of the hole in the member, and provides an operator perceptible indication of a radial direction from the drill opening to the axis.

Abstract: A compact surgical handpiece comprises a motor energizable for moving a tool member, electric energy supply actuable for energizing the motor and a manually actuable trigger actuable to control motor operation. A motor control circuit interconnects the motor electric energy supply and trigger for running and braking the motor in response to actuation and release of the trigger. The control circuit includes a compact regulated voltage supply, a motor overcurrent limiting feature and a motor braking feature which is effective even if the operator fails to fully disconnect the electrical supply to the motor upon releasing the trigger.

Abstract: A compact surgical handpiece comprises a motor energizable for moving a tool member, electric energy supply actuable for energizing the motor and a manually actuable trigger actuable to control motor operation. A motor control circuit interconnects the motor electric energy supply and trigger for running and braking the motor in response to actuation and release of the trigger. The control circuit includes a compact regulated voltage supply, a motor overcurrent limiting feature and a motor braking feature which is effective even if the operator fails to fully disconnect the electrical supply to the motor upon releasing the trigger.

Abstract: A battery charger for alternately receiving batteries having substantially different charging rate requirements in which the charger has contacts engaged by a battery pack to be recharged, for the purpose of carrying out such recharging. A difference in at least one of the charger contacts is engageable by one of the high and low charge rate battery packs, but not the other. Whether or not that one charger contact is engaged by a battery pack causes the battery charger to supply charging current at different levels to automatically charge such high and low charge rate battery packs at corresponding high and low charge rates.

Abstract: A compact surgical handpiece comprises a motor energizable for moving a tool member, electric energy supply actuable for energizing the motor and a manually actuable trigger actuable to control motor operation. A motor control circuit interconnects the motor electric energy supply and trigger for running and braking the motor in response to actuation and release of the trigger. The control circuit includes a compact regulated voltage supply, a motor overcurrent limiting feature and a motor braking feature which is effective even if the operator fails to fully disconnect the electrical supply to the motor upon releasing the trigger.

Abstract: A dc permanent magnet motor for a surgical handpiece, comprises a housing and a stator including windings fixed in the housing. A rotor is supported for rotation in the housing and has a forward extending rotatable shaft. A conventional sensor adjacent the windings and rotor has stiff conductive electrodes extending rearward. A printed circuit board disk has plural axial holes along the perimeter thereof defining conductive sockets into which the electrodes plug, which disk is located coaxially rearward of said rotor and windings and is fixed with respect to the housing. A rear-facing, separable connector holder behind the printed circuit board has terminals rear-facing therefrom for connection to an external electrical supply. The holder is fixed with respect to the housing. Electrical connections are effected between the conductive sockets of the printed circuit board and the rear-facing terminals of the holder.