GB841109A - Apparatus for jointing individual cores of cables - Google Patents

Abstract

841,109. Covering cable joints by injection moulding. THOMPSON, R. F., and BREACH, A. C. E. Feb. 21, 1958 [Feb. 22, 1957], No. 6095/57. Class 87(2). [Also in Groups XXVIII and XXXVI] The joint between a bared portion of cable 1, Fig. 1, and the bared end of cable 2 is enclosed in a two-part mould 5 into which polythene or other thermoplastic material is injected by means of the " gun " shown in Fig. 2. The gun has a plunger 8, the rear end of which is formed with a series of ratchet steps 14 and operates in a barrel 7 in co-operation with a pawl assembly 17. The handle 9 is provided with a pivoted spring pressed trigger 10 having a groove 34 co-operating with a pin 33 fixed in a forked piece which is secured by two arms held in a slide in the gun body to the pawl 17. Operation of trigger 10 moves plunger 8 forward in the barrel by pulling forward the pawl assembly 17. When the trigger is released spring 12 moves it outwards and pawl assembly 17 is moved backwards ready for the next operation of the trigger, the catch members 22, 24 riding up the sloping surfaces of the steps with which they are in contact so as to expand outwardly against the restraint of circlip 23. To charge the gun, the trigger 10 is moved to its fully closed position against wall 13 in which position the rear end 46 of the barrel has moved the catch members 22, sufficiently far apart to enable the plunger 8 to be withdrawn from the barrel. A charge of e.g. polythene is then inserted in the barrel, the plunger is replaced and the trigger released. The plastic insulating material in the barrel is then melted by energizing heating coils 42 under control of a thermostat 44. When melting point is reached nozzle 35 of the gun is engaged with the bayonet joint entry connection 6 on the mould and the trigger is operated until the mould is filled with the plastic insulating material.