GB648429A - Improvements in or relating to riveting tools - Google Patents

Abstract

648,429. Blind riveting. BRITISH UNITED SHOE MACHINERY CO., Ltd., COOPER, B. P., and HENSHAW, J. N. June 16, 1948, No. 19098. [Class 43] In a manually-operated blind-riveting tool wherein a rivet is set on actuation of a lazy tongs device by means of a member, such as a push-knob, said member is prevented from swinging relative to the device. The tool may be adapted to receive mandrels of different diameters by applying thereto different nose pieces which separate the mandrel-engaging jaws by varying amounts according to the size of the mandrel to be used. In many respects the tool resembles that described in Specification 348,818. The lower end of the push knob 23 of the lazy tongs device is forked to straddle the uppermost levers 21, 21<SP>1</SP>, and is pivoted together with said levers on a pin 20, slidable in the stem part 63 of an inverted T-shaped slot 61 in a controlling member 59; the cross-bar part 65 of the slot receives pins 67, 67<SP>1</SP>, which are fixed to the levers 21, 21<SP>1</SP>, and are equally spaced from the pin 20, and a pin 69 extending upwardly from the member 59 is slidable in a bore 71 in the knob 23. The knob is thus restrained from swinging relative to the lazy tongs. The lower levers 15, 15<SP>1</SP>, pivoted at 13, 13' to the casing 11, are extended at 25, 25' to carry rolls 27, 27<SP>1</SP>, which engage in slots 29, 29<SP>1</SP> in a head 31 secured to a cylindrical sleeve 33 slidable in the casing. The lower end of the sleeve 33 has opposed, inclined, part-cylindrical bearing surfaces 35, the angle of inclination to the axis of the sleeve being the same for both surfaces; opposed bearing surfaces 37 of two jaws 39 are complementary to and slidable on the surfaces 35, so that the mandrel-gripping surfaces 41 of the jaws extend in the direction of the axis of the sleeve 33 for all positions of the jaws and will thus grip a mandrel along their whole length. The initial position of the knob 23 is determined by the engagement of the head 31 with stop surfaces 43 of the casing 11, and the initial separation of the jaws 39 is controlled by one of several interchangeable nose pieces 45, each having a cylindrical bore 47 which is coaxial with the sleeve 33 and corresponds in diameter to the size of the mandrel to be used. The nose piece, the lower end of which forms an abutment for holding a rivet up to the work, screws into an end cap 49 of the casing 11, its cam-shaped upper end 51 and the cam-shaped lower end 53 of a member 55, slidable in the sleeve 33 and urged downwards by a spring 57, engaging part-conical surfaces at the base and upper end respectively of the jaws 39 and thus holding them the required distance apart. To change to mandrels having smaller diameters than those first used, a nose piece having a smaller bore and not extending so far into the tool is used, so that the jaws are pressed further down and hence closer together by the spring 57, but still remain in the same angular relationship. Specification 504,928 also is referred to.