Patent GB-687887-A (GB)
Title: Improvements in automatic riveting machine
IPC: B21J15/46
Filed: 1950-12-01
Abstract: 687,887. Riveting. THOMSON MANUFACTURING CO., J. L. Dec. 1, 1950 [Dec. 29, 1949], No. 29474/50. Class 83 (iv). [Also in Group XL (b)] In a riveting machine in which anvils for receiving the parts to be riveted are successively brought into position for riveting, the rivetdriving mechanism actuates means for moving the anvils after each rivet has been driven, an adjustable time delay device being provided to control the intervals between actuations of the rivet driving mechanism to allow time for work to be placed in position on the anvils. A machine for riveting assembled parts, Figs. 5 and 6, by means of tubular rivets 102 and washers 104 has a crank-operated rivet feeding and setting mechanism 5 supplied with rivets from a hopper 25 and driven by an electric motor 10 through a shaft 14 and a one-revolution clutch which is engaged by the closing of a solenoidoperated switch. An adjustable dash-pot delays closure of the switch until a predetermined interval of time after current has been passing through the solenoid. A switch 72, Fig. 2, in the circuit of the solenoid-operated switch is closed by one of a number of pins 73 only when the turret is in its proper indexed position. A main switch 56 for the motor 10 and footoperated switch 70 also in this circuit are used by the operator to stop and start the machine at will. The indexing mechanism for the turret 3, Fig. 2, comprises a double-acting solenoid-operated ram 36 which oscillates a bar 39 carrying a spring- loaded pawl 42 which engages toothed wheel 41 on the turret 3. In the indexed position the pawl 42 is locked in the wheel 41 and positively located by a fixed stop 45, which releases the pawl when the ram 36 rotates the bar 39 anticlockwise, a spring 43 causing the pawl to engage a tooth on the wheel 41 as soon as the bar moves clockwise so that the turret is moved therewith. Trip switches 47, 65 one in each of the circuits of twin solenoid-actuated valves of the ram 36 reverse the action of the ram at each end of its stroke. A further switch 48 in circuit with the trip switch 47 is momentarily closed by a cam 50 on the drive shaft 14 of the rivet-setting mechanism just before the mechanism reaches the stop position, and ensures that the ram 36 does not operate to move the turret 3 until after the rivet-setting operation is completed. The riveted part is removed from the anvil at the next indexed station by a jet of compressed air from a nozzle 130, and delivers the part into a shoot 131. In a modification, Fig. 10, assembled parts 113 are fed to anvils 110 down a shoot 112, a retractable spindle 114 on each anvil picking up one of the parts by engaging a central hole 115 in the part on each indexing movement of the turret. An electric eye 121 at a station prior to the riveting station detects if there is a part 113 in position for riveting and prevents actuation of the setting device 5 if the part is absent. A beam of light from a source 120 is interrupted by the parts in turn and the electric eye 121 actuates a solenoid-operated switch 122 which is used in place of the switch 72 to close the circuit through the switch 80 controlling the actuating device.