GB542127A - An improved device for clamping together pieces of sheet material - Google Patents

Abstract

542,127. Internal clamps. FERNBERG, E. B., and FERNTOL PATENTS, Ltd. April 24, 1940, No. 7382. [Class 44] A fastener of the kind described in Specification 541,104 for holding together plates 43, 44 to be riveted &c. comprises two tongues 34, 35 provided with cooperating bends or other offset surfaces 41, 38 of such a form that when the tongues are moved longitudinally relatively to each other in one direction they approach one another laterally so that they can be inserted through the work and in the other are moved apart. The tongues may be operated by screwed members 56, 57, Fig. 10, or by a spring loop 30, Fig. 1, and the tongue 34 may have a reduced width at 48, with or without arms 39 to form a shoulder to engage the upper face of the work. The bend 38 may engage the lower face of the work and this tongue 35 may be extended and be formed with a stop to limit the separation of the tongues. In a modification the tongues 58, 59, Fig. 11, may have semicylindrical section the co-operating offset surfaces being inclines or a groove 60 and hump 61 which may be formed by drilling a hole 62, Fig. 13, and securing a pin in one of the grooves so formed. The arms 39 and the spring loop 30 may be reinforced by additional members and piers with jaws 70, 71, Fig. 16, rounded in both directions may be used for compressing the spring loops when inserting the fasteners.