Abstract: A fusing apparatus and method is described for forming a fuse joint between an armature wire having electrical insulation thereon and a terminal extending from a commutator bar. The apparatus includes a U-shaped fusing electrode including a central portion having an effective electrical resistance higher than the remaining portions of the electrode. By applying current through the electrode, the central portion is heated to a temperature higher than the remaining portions of the electrode sufficient to remove the electrical insulation from the armature wire and to fuse the armature wire to the terminal.

Abstract: The present invention provides a method and apparatus for controlling the amount of heat energy supplied by a bonding transformer to coil windings to heat the windings to a predetermined temperature level for fusing the windings into an integral mass. This is accomplished by continuously monitoring the current level in the secondary windings of the bonding transformer and comparing the signal produced with a signal preset in a comparator, which preset signal corresponds to the heat energy required by the coil windings to heat them to the predetermined temperature level. The comparator then operates to deactivate the bonding transformer when the monitored signal corresponds to the predetermined temperature level desired in the coil windings.

Abstract: A novel control arrangement is provided for controlling the operation of the heating electrodes of a brazing machine for forming a joint between an armature wire and a commutator bar. The heating electrodes are brought into contact with the armature wire and commutator bar at the point where they are to be joined, and fiber-optic means are provided for collecting radiant energy emitted from a point at or adjacent to the joint area as the joint is being heated. The collected radiant energy is converted into a usable electronic signal representative of the temperature at the joint area, and the heating electrodes are actuated on and off in response to the electronic signal when the temperature at the joint reaches predetermined upper and lower temperature levels. As a result, the temperature of the heating electrodes and joint area is maintained within a desired temperature range while the joint is being formed.