Patent GB-821525-A (GB)
Title: Improvements in or relating to apparatus adapted for use in assembling electrical components upon wiring boards
Inventor: MAKOVSKI STEPHEN AKROYD
IPC: H05K13/04
Filed: 1956-02-03
Abstract: 821,525. Assembling electrical components on circuit boards. BRITISH UNITED SHOE MACHINERY CO. Ltd. (United Shoe Machinery Corporation). Feb. 4, 1957 [Feb. 3, 1956; Aug. 9, 1956; Dec. 28, 1956], Nos. 3403/56, 24393/56 and 39395/56. Addition to 802,659. Class 83 (2). In apparatus as described in the parent Specification for use in assembling components, such as electrical components, upon workpieces, such as wiring boards, which are detachably mounted on pallets P carried by a conveyer 730 through a number of work stations, the pallets are discharged automatically from the conveyer after leaving the work stations. The apparatus is preferably of the kind described in Specification 819,969, wherein a wiring board is mounted on a pallet at one station and after assembly of the components the board is dismounted from the pallet and discharged down a shoot from the apparatus. The empty pallet then passes along the upper reach 950, Fig. 7, of the twinbelt conveyer and at station 34 is canted sideways and tipped between the belts into a shoot 58 which delivers it to the lower reach 952 of the belt where it is again tipped between the belts into a shoot 68 which delivers it to an auxiliary return twin belt conveyer 72. At the opposite end of the apparatus the pallets P, Fig. 6, conveyed by the auxiliary conveyer, are released one at a time in sequence with the operations at the work stations by a solenoidoperated plunger 100 and pass upwardly along a curved inclined plate 136, Fig. 13 (not shown), whereupon the leading end of the pallet is gripped between an inclined belt conveyer 102 and a resilient toothed feed roller 106, mounted on links 130 pivoted at 124, and is fed between the conveyer 102 and an adjacent toothed belt 104. The pallet is thus raised until its leading edge engages an adjustable deflector blade 162 which, in combination with a flexible member 170, tilts it into a shoot 174 leading to the upper reach 950 of the main conveyer. The pallet subsequently, actuates a switch 202 controlling the plunger 100 to permit release of a further pallet from the auxiliary conveyer 72. Conveyers 72, 102, 104 and roller 106 are preferably driven by chains from an electric motor 140 controlled by switch 141. In another embodiment, Fig. 20, the pallets P are returned along the lower reach 952 of the main conveyer belts 730 pass over pulleys 230, 232, 234, Fig. 19 (not shown) on shaft 236, and pulleys 238, and 240. In passing between the pulleys 230 and 238 the two belts are moved apart to accommodate therebetween a lifting mechanism 254. The latter comprises a link 260 carrying two guides 281, pivoted at 231 and movable by a pneumatic motor 262 from an inclined position where it is aligned with the inclined lower reach 952, Fig. 19 (not shown), to a horizontal position where it is aligned with the upper reach 950. When the lifting-mechanism 254 has been lowered, a pallet is fed under the control of spring-biased interconnected stops 314, 320 operated by the lifting mechanism, up the inclined guide-rails 281 to abut against a stop 333 and actuate a switch 354. A previously-fed pallet is then engaging stops 338, 340 on the upper reach 950. When these stops are released in correct time sequence with the operations at the work stations, this previous pallet moves along the upper reach and actuates a micro-switch 352, Fig. 17 (not shown) which causes the motor 262 to raise the mechanism 254. An auxiliary conveyer belt 282 passing around pulleys 280, 287, 286 on the mechanism 254 is thus tightened against a pulley 288 driven from the main conveyer belt shaft 242 and feeds the pallet forwardly to abut against the stop 338. Provisional Specification 821,525 also describes another mechanism wherein pallets on the lower reach are raised to a pallet hopper adjacent the upper reach by an inclined chain conveyer.