Patent GB-856583-A (GB)
Title: Improvements in or relating to winding electrical units, for example capacitors
Inventor: STRICKLAND WILLIAM ALFRED DUDL
IPC: H01G13/02
Filed: 1956-02-06
Abstract: 856,583. Winding webs. DUBILIER CONDENSER CO. (1925) Ltd April 26, 1957- [Feb. 6, 1956]. No. 3683/56. Class 100(1) A method of winding electrical components, e.g. capacitors, of the kind comprising an electrically conductive strip in the form of convolutions spaced apart by one or more spirals of dielectric strip material, wherein the conductive strip is cut at a point further from a winding mandrel than a point at which the conductive strip and the dielectric strip or strips are normally first brought together before being drawn on to the winding mandrel, winding is continued until dielectric strip alone is drawn on to the mandrel, and the dielectric strip or strips are cut at a point nearer the winding mandrel than the point of cutting of the conductive strip, the cut end or ends of the dielectric strip then being attached to a winding mandrel, and either during or subsequent to the winding of the residual portion of the conductive strip into the previous component, the cut end of the supply of conductive strip and the dielectric strip or strips are pressed towards one another to cause such conductive strip again to be drawn forward with the dielectric strip or strips during the winding of the next component. As shown, an electrically conductive strip C<SP>1</SP>, Fig. 2, interposed between two plastic dielectric strips C<SP>2</SP>, C3, is wound on a mandrel E to form a capacitor. A frame member A pivoted about an axis J carries guide rollers B<SP>1</SP>, B4 and guide rods B2, B3. A further conductive strip C4, interposed between two dielectric strips C<SP>5</SP>, C6 is guided by a similar frame member, not shown. The conductive and dielectric strips are also drawn around fixed guides, not shown, before engaging the guides carried by the movable frame member. The conductive strip C<SP>1</SP> is drawn from a roll F<SP>1</SP>, Fig 4, braked by a spring arm F<SP>2</SP> engaging a boss F<SP>1</SP>. The arm F<SP>2</SP> has a spiral spring F3 wound around a peg F4. The brake may be released by an arm F<SP>5</SP> carrying a projection F6 and rocked by a rod F<SP>7</SP>. The strips C<SP>1</SP>, C<SP>2</SP>, C<SP>3</SP>, Fig. 2, are drawn from the guide rollers and rods tangentially on to a rotatable drum D, the strips being thereby compressed. The drum D is mounted to permit the drum moving away as the diameter of the capacitor on the mandrel E increases. A cutting device G<SP>1</SP>, G<SP>2</SP> having a cutting edge G cuts the strip C<SP>1</SP> upon rotation of the device about an axis parallel to the cutting edge. A similar cutting device G3, G4 is provided for the strip C4. In operation, when a capacitor is almost complete the devices G<SP>1</SP>, G2 and G3, G4 are operated to cut the strips C<SP>1</SP>, C4. A few turns of dielectric strip continue to be wound to form an outside layer for the capacitor and then the strips C<SP>2</SP>, C3, C5, and C6 are severed by a heating device H which also fuses their cut ends to the capacitor body which is subsequently removed from the mandrel. The free ends of the dielectric strips are then attached to the winding mandrel E to commence winding another capacitor. The free end of the conductive strip C<SP>1</SP> hangs loosely from the roller B<SP>1</SP> and a co-operating spring- urged roller B4. The frame member A is then rotated clockwise, such that the strip C<SP>1</SP> is held between the strips C<SP>2</SP>, C3. The strip C<SP>1</SP> tends to adhere to the strips C2, C3 due to an electrostatic charge on' the strips C<SP>2</SP>, C3. In this position of the frame member A, the axes of the guide rods B<SP>2</SP>, B and the roller B<SP>1</SP> lie substantially tangential to the drum D. Simultaneously with the rotation of member A the rod F<SP>7</SP>, Fig. 4, is actuated to release the braking action of the arm F<SP>2</SP> to permit the strip C<SP>1</SP>, Fig. 2, being drawn forward freely. The member A and arm F<SP>2</SP>, Fig. 4, are returned to their initial positions when the strip C<SP>1</SP> is held tightly between the strips C2, C3. In a modification, Figs. 6 and 7, not shown, a single dielectric strip is associated with each conductive strip, these strips being guided prior to winding by members carried by separate frame members rotatable to cause feeding engagement of the cut ends of the conductive strips with the dielectric strips. The frame members are simultaneously rotatable through co-operating gearing.