GB785423A - Method and apparatus for the mechanical separation of a part from a rod- or tube-like work piece - Google Patents

Abstract

785,423. Glass manufacture. SICKEL, H. May 14, 1956 [May 14, 1955], No. 15021/56. Class 56. A part is separated from a glass or like rod or tube by heating the rod or tube at the separation point, potentially loading a force and holding the same inactive, and releasing said force to act upon the rod or tube at the moment of suitable softening to cause sudden breaking off of the said part. The invention is described as applied to the sealing of ampoules by heating the necks and drawing the parts to be separated away from the ampoules, the sudden breaking off reducing the tendency, normally present with more gradual separation of the parts at the heated zone, to produce a seal with glass walls which are too thin. As shown in Fig. 1 (III) ampoules K are fed in succession to a position beneath grippers C, the ampoules being supported in means 52, 53, rotated by a soft roller 54 and steadied by a member 51 near the zone of separation which is softened by a burner 57. The separation is effected by a rod 32 which rises and falls. When the rod is falling, the grippers C are presented to the ampoule tip, the jaws of the gripper being kept open by the bottom of the sleeve 34 pressing on the arms 43, When the rod starts to rise the jaws grip the ampoule tip under the pressure of a spring 42, the arms 43 being released. The member 31 which rises and falls with the rod 32, first removes a catch 15 from under the cone head of the weight E, so that a slight pull is exerted on the ampoule tip to produce a slight drawing of the softened glass when the correct temperature is reached. This drawing is braked by an arcuate member 11 on an arm 10 having an adjustable counterweight (not shown) which regulates the pressure of the member 11 against a conical ended weight D which is thereby pressed against a projection 3<SP>1</SP>. As the weight system descends, the bottom cone of the weight D swings the arm 10 outwardly and removes its inturned end from a groove in the main weight F which is suddenly released and falls into contact with the cone head of the weight E, and jerks the grippers C away from the ampoule body. The grippers at the top of their movement are opened by the contact of the arms 43 with the underside of sleeve 34, the telescopic part 36 being pressed against the stationary surface 4. The separated ampoule tip is discharged into a shoot which is automatically swung into and out of receiving position. When the rod 32 falls, the apparatus is reset in position to receive another ampoule. The grippers C may be carried on a rod which is slidable and rotatable in the guide tube 36, the upper end of the rod being connected by the cable to the weights D, E, F. In a further modification, the grippers are carried on a rod which slides axially and rotates in a bearing, the grippers being opened when the rod is depressed. The mechanism is actuated by a vertical rod which reciprocates vertically and depresses the gripper carrying rod. On its upstroke, the grippers close and grip the ampoule tip, whilst further up-movement compresses a spring against an abutment member which is held by a pivoted latch which is released by the slow upward movement of the grippers, as permitted by the softening of the separation zone, under the influence of a weaker spring in the bearing member for the gripper-carrying rod. The operation of the latch brakes this movement; but when the latch is released, the compressed spring acts suddenly to move the abutment member upwardly, taking the grippers with it and thus breaking the ampoule tip abruptly from the ampoule body. In Fig. 8, the grippers 104 are carried by a parallel linkage 101, 102 which, at the beginning of a cycle of operations, is horizontal so that the grippers engage the ampoule tip. The grippers are opened by the pressure of a lever 107 on the plunger 105, the lever being normally held inoperative by a leaf spring 108. The lever 102 has an extension 109 on which a weight 111 is slidably adjustable and a weight 110 is pivoted at 126 so that, at the start of a cycle, it is vertically disposed resting against an adjustable abutment 112. When the zone of separation is sufficiently softened, the weights 111, 110 effect a slow separation until the slope of the linkage is sufficient to overbalance the weight 110 which then falls suddenly on to the extension 109 and produces a sudden upward movement of the grippers. This brings the end 106 of the lever 107 against the plunger 114, depresses the plunger 105 and opens the grippers, allowing the separated tip to take a curved path into a receptacle 122. The apparatus is reset by an upward movement of the rod 115 to restore the linkage to the horizontal position, the grippers remaining open to receive another ampoule, until the end 106 is released by the falling rod 115. The weight is restored to its vertical position by a vertically reciprocating lifter 116, 117. In the modification shown in Fig. 9, the weight 110 has a projecting arm 123 which contacts with a spring 124 when the weight 110 starts to overbalance. This temporarily slows up and reverses the upward movement of the grippers to produce a thickening of the glass at the zone of separation. When the arm 123 clears the spring the weight 110 falls over freely and produces the abrupt separation of the ampoule tip. In a modification, the linkage 101, 102 is heavier at the grippers end, so that when the separation zone softens, the grippers fall and thicken the glass. The fal produces a rise of the pivoted weight which abuts against stationary cam means which forces it to fall over and produce the abrupt separation of the tip.