Patent GB-800333-A (GB)
Title: Improved device for applying mastic coated tape
IPC: E04F21/00
Filed: 1956-07-05
Abstract: 800,333. Applying mastic coated tape. AMES, R. G., AMES, U. S., WILLIAMS, G. W.. WILLIAMS, K. A., and ROSEBROOK, L. H. July 5, 1956, No. 20887/56. Class 73 Relates to a taping device for applying a mastic coated tape, e.g. to the joints of wall boards. According to the invention the device comprises a hollow handle A, Figs. 1, 7, adapted to hold mastic P which is forced from a nozzle 2 by a piston E on to tape D fed from a roll over tape applying wheels 33, the wheels 33 being geared to a rotatable drum shaft L around which is wrapped a wire 19 connected to the piston E, so that rotation of the wheels 33 to apply the tape will advance the piston for forcing the required amount of mastic on to the tape just prior to its application. A slidable sleeve C is mounted on the body A by means of rollers 4 and forward movement of the sleeve initiates forward movement of the tape through a tape guide N on to the peripheries of the wheels 33 without any movement of the piston E. Rearward movement of the sleeve C operates a cutter movable transversely in a guide 57 at the forward end of the tape guide N for cutting the tape. The tape guide N, Figs. 6, 7, comprises a plate 28 with channel-shaped sides 29 receiving the edges of the tape D, and at the ends of the plate 29 transverslyextending strips 30, 31 are provided. The plate 28 has a longitudinally extending slot 32. A member 34 secured to one side of the plate 28 is provided with a cam slot 35 adapted to receive a pin 41, Fig. 10, on a lug 40 projecting from a sleeve 38 slidable on a guide rod 39 also secured to the plate 28. Another projection 45 on the sleeve 38 carries a spring-urged pivotally mounted needle 42 so arranged that rocking movement of the sleeve 38 about the rod 39 causes the needle 42 to enter or retract from the slot 32 in the plate 28 and thus engage or disengage from the tape D. A rod 36 fixed to the sleeve C has an arm 37 adapted to abut against the lug 40 so that forward movement of the sleeve C moves the pin 41 along the cam slot 35 and causes the tape feeding needle 42 to engage in and move along the slot 32 thus feeding the tape forwardly. On retraction of the sleeve C the sleeve 38 is spring-urged back along the cam slot 35 to its original position, the needle 42 riding over the tape during this rearward movement. The cutting knife 58, Fig. 9, is secured to a carriage 59 slidable in a runway 57 located at the forward end of the tape guide N and a chain 61, Fig. 6, connected to the carriage 59 extends along the runway 57. The chain passes around idlers 62, 63 and one end is eonnected by a flexible member 64 with the arm 37 of the rod 36 rigid with the sleeve C. The opposite end of the chain is connected to a coil spring 65 secured in turn to one side of the tape guide N. The flexible member 64 permits forward movement of the sleeve C without actuating the cutting knife but rearward movement of the sleeve C tensions the member 64 and pulls the knife along the runway 57 to sever the tape. An inlet check valve F, Fig. 7, is provided for filling the handle A with mastic, a blade valve G being moved to close off the nozzle 2 during filling.