Patent GB-979697-A (GB)
Title: Improvements in and relating to the sealing together of hollow glass parts
IPC: H01J5/24
Filed: 1963-09-11
Abstract: A method of sealing together two hollow glass parts comprises the steps of axially moving the two parts relative to each other so as to bring the parts more closely together, mechanically sensing the position of the edge of one part as the other part moves relatively towards it, mechanically sensing the position of the complementary edge of the said other part as it approaches the said one part, and causing the mechanical sensing of the edge of the said other part to establish a subsequent cycle of relative movements of the parts towards one another to produce a seal between the two parts.  An apparatus for carrying out the method comprises a bed 21 to which is attached a fixed head stock 22 and a horizontally slidable tail stock 23, a burner assembly 30 supporting burners 31 and mounted for horizontal sliding movement, and a mechanism 33 with a control unit 32 for mechanically sensing the relative positions of the edges of two components to be sealed and thereafter to establish a cycle of operations which will do the sealing.  A television tube funnel sub-assembly 24 is mounted in a rotatable chuck in the head stock and a face plate 25 is mounted in a rotatable chuck in the tail stock. The burners 31 have means to allow them to follow the outside contour of the two hollow pieces whatever the shape.  The cycle is started by energizing valves 150, 151 and 160. Energizing of valve 151 actuates the fluid piston motor 45 which swings the sensing unit 32 down into a horizontal position so that its fingers 35, 36 are between and in line with the sealing edges of the funnel 24 and plate 25.  The sensing fingers 35, 36 are each connected to arms 37, 38 which are linked together through a parallel link system to maintain the arms 37, 38 always horizontal in the down position.  Energizing of the valve 150 actuates piston motor 84 which moves a slide 81 and attached arm 81a to which is fixed the tail stock 23 in order to move quickly the face plate near to the funnel. At the end of the stroke of piston 84 but before any contact is made by the sealing edges, a limit switch 106 is operated by a cam 127 on a bar 128 connected to an arm 112 thus energizing a valve 155 which actuates piston motor 90 in order to continue more slowly the forward movement of the tail stock along with the fingers 35, 36.  When the finger 35 contacts the sealing edge of the funnel, the forward movement of the bar 37 is stopped.  The continued movement of the tail stock 23 brings a limit switch into contact with a cam 56 on the bar 37 thus operating the switch which in turn energizes a valve 153 to actuate a piston motor 147 to force a clamp 141 against a slide 116 and fix a limit switch 115 in a position with relation to the fixed sealing edge.  The tail stock still continues and brings the face plate sealing edge into contact with the finger 36 which moves the bar 38 in relation to bar 37 until a cam 60 on a bar 37 operates a limit switch 62 energizing a valve 152 to actuate piston motor 146 and move a clamp 140 against a slide 107 to fix the position of limit switches 104 and 105.  Switch 62 also de-energizes valve 160 which stops the piston motor 90 and the tail stock, and also de-energizes valve 151 which causes motor 45 to swing the sensing unit 32 clear of the glass parts.  Retraction of the piston motor 45 operates a switch 75 which starts timers in the electrical circuit to control subsequent operations and also commence rotation of both chucks holding the funnel and face plate.  A timer energizes valve 154 which actuates the blind end of a piston motor 98 to move the burner carriage 30 through an arm 96 and slide 95 until a cam 133 on a bar 134 operates the limit switch 115 to de-energize valve 154 and stop the burner carriage in a position to start the sealing cycle.  Timers also energize and <PICT:0979697/C1/1> <PICT:0979697/C1/2> <PICT:0979697/C1/3> <PICT:0979697/C1/4> de-energize valves 156-162 which control the speed of advancement of both the tail stock and the burner carriage 30.  A limit switch 105 actuated by a cam 126 on a bar 128 is used to interrupt the time-controlled movement of the tail stock 23.  The travel of both the tail stock and the burner carriage continues until a limit switch 104 operated by a cam 125 signals that a seal has been made.  This resets the timers which have been in operation up to that time, and shifts the control to another timer for cooling and returning all valves and cylinders to their starting positions.  U.S.A. Specifications 2,832,602 and 2,895,739 are referred to.