Patent GB-775926-A (GB)
Title: Joint forming mechanism
IPC: B65B13/34
Filed: 1955-04-15
Abstract: 775,926. Sealing bale ties. SIGNODE STEEL STRAPPING CO. April 15, 1955 [April 22, 1954], No. 10939/55. Class 146(2). A mechanism for joining overlapping strap ends with an embracing seal comprises a pair of jaws having forward hooked tips and mounted for rectilinear and pivotal movements so that the tips may pivot towards and away from each other when the jaws are in an advanced position, the tips being formed to receive the flared flanges of a seal and to fold the flanges over the strap when the tips pivot towards each other, and a pair of notchers movable in the direction of rectilinear movement of the jaws, the jaw tips having cutting edges which coact with the notchers, when the latter are moved relatively to the jaws, to deform the strap and seal. In operation the strap is pushed through slots 124, 138, 110, in guide block 106, stationary cutter and clamping block 108, and barrier 112, and around the track encircling the bundle so that the free end impinges face 140 of guide finger 142 and wedges against face 118 of barrier 112 and the strap. When the machine is started the strap is tensioned, and fluid entering cylinder 48 advances pistons 60, 70, and push rod 44, and through yoke 234, 226, 224, and pins 216 advances the jaws until slots 212 arrest pins 206, pins 216 then entering slots 222 so that the jaws pivot. Simultaneously yoke 234 acts through cam surface 258 to swing finger 142 outwardly, barrier 112 is retracted through the jaw acting on link 262, and the seal ejector assembly is raised by the push rod acting through cam 188, pin 184, and arms 180. As the jaws pivot edges 291 offset and clamp the strap against shoulder 293 on block 108, and flanges 176f are folded about the strap. The strap is then tensioned as required, and fluid then introduced between pistons 60 and 70, the resulting movement of piston 70 rocking the jaws further to clamp flanges 176f firmly. At the same time yoke 234 advances notchers 318 and cutter block 330 forwardly, the jaws not now moving longitudinally, edges 320 of the notchers coacting with the cutting edges 304, 306 of the jaws to form notches 316 and deform the strap and seal, and the edge 334 of cutter 330 shearing the strap 102s against the cutting edge 336 of the stationary cutter 108, and bending the tab end 102t into recesses 294 in the jaws, so that the strap ends does not protrude, see Fig. 10. Cutter block 330 is reversible. The ports are returned by venting the space between pistons 60 and 70, and admitting fluid at 78. At the conclusion of movements pin 184 rides off the cam surface 188 and spring 183 snaps the ejector assembly 178 downwardly, carrying a seal from the magazine 158 to loading position between the jaws where it is supported on jaw shelves 296 and the top 332 of cutter block 330, the yoke engages the cam surface 288 and moves lever 264 and hence through 272, 262 the barrier 112 is moved into strap blocking position, and spring 152 moves finger 142 into strap guiding position when the yoke rides off the cam surface 258 of the finger. Each jaw, Fig. 9, comprises bores 208, 218 for pins 206, 216, a slot 298, a shoulder 300 forming a pocket 302, cutting surfaces 304, 306, and a curved face 294 terminating in the shelf 296. The lower blade of the notchers slides in the slots 298 of the two jaws, and the upper blade slides on the top of the jaws and anvil 310. Specifications 675,310 and 749,926 are referred to.