Patent GB-806921-A (GB)
Title: Improvements in and relating to machines for sealing electrically conductive button elements into glass envelopes
IPC: H01J9/46
Filed: 1955-10-20
Abstract: 806,921. Sealing electric conductors into glass envelopes. CORNING GLASS WORKS. Oct. 20, 1955 [Oct. 21, 1954], No. 30027/55. Class 39(2) [Also in Group XXX] Apparatus for feeding electrically conductive button element, such as a metal terminal button to a position above the wall of a glass envelope, such as a cathode ray tube, and depositing it upon the wall preparatory to its being sealed therein, is provided with means for feeding the button or element automatically into a position for seizure by a holder in a carrier, whereupon the seized button is advanced into a position for its deposit on the part of the tube registered beneath it. The invention is described as applied to the machines described in Specifications 698,052 and 790,234, comprising a turret which is indexed about a vertical axis and has ten chucks spaced around its periphery to receive cathode ray tubes which are halted beneath ten successive work stations mounted around the periphery of a stationary spider that is coaxial with the turret. A button-depositing device is mounted at station 6 so that it deposits a button upon an aperture made in the tube at station 5, and the operation of the button depositing device is controlled by cams on the main cam shaft 144, Fig. 5, which, through compressed air actuated devices, also effects the indexing of the turret and the operation of the glass perforating punch, as well as the advance of a die 60 into vertical alignment with the punch. At station 6 the spider arm 36, Fig. 2, supports a pneumatic unit 72, shown also in Fig. 5, comprising a cylinder containing a piston with a tubular piston rod 73 the upper end of which connects through a valve V10 to a vacuum source 151 so that the lower end 79 of unit 72 acts as a suction holder for button located beneath it. Buttons are fed continuously to a trough 80 at station 6, e.g. by a vibratory feeder 82 which receives them from a supply source, there being an escapement device or reciprocating gate 83 at the bottom of the trough under the control of a pneumatic unit 84 which releases one button at a time. An air stream from a nozzle 91 assists the movement of a released button to a position below the suction holder 79, the button then being supported on a pair of counter-balanced trap doors 74 that permit the suction holder, after moving downwardly to engage a button, to continue its downwards movement to place the button upon the apertured part of the cathode ray tube disposed beneath it, whereupon the button is released by cutting off the vacuum. The suction holder 79 is normally held in its upper or retracted position by compressed air fed to its lower end through line 150 and valve 77, and is depressed by pressure fed to its upper end through a line controlled by a normally closed magnetic valve 125, Fig. 5, that is opened only when a tube is positioned to receive a button, when contacts 126, in the energizing circuit of the valve are closed by the action of a roller 85, Fig. 2, engaging the part 40 of a tube indexed to position 6. A cam 140 controls the indexing operations by way of a pneumatic unit 123 controlling a single revolution clutch on a shaft 17 associated with an indexing wheel 16, Fig. 4 (not shown), which engages vertical rollers spaced around the underside of the turret. At the end of each indexing movement a cam 143 on the main cam shaft 144 actuates a valve V10 to connect the button holder 79 to the vacuum line 151, and a cam 142 actuates a valve V3 to connect a four-way control valve 100 to the pressure line 150 and move the spool 110 thereof to the left, as shown in Fig. 5. A manifold 102 connected to the front end of the die unit 62 at the perforating station 5 is thus connected to atmosphere, whilst a manifold 101 is connected to the pressure line 150 and delivers compressed air to the rear end of unit 62 to actuate the perforating-die. At the same time compressed air is fed through the manifold 101 and solenoid valve 125 when contacts 126 are closed by a tube located at station 6, thereby operating unit 84 and gate 83 to separate a button 81 from the series behind it, and operating the unit 72 to lower the suction holder 79 to seize the button below it and push it through the flaps 74 on to the glass wall below.