Patent GB-1463820-A (GB)
Title: Mechanism for converting reciprocation into intermittend  alternating tripped  rocking motion
IPC: F16H21/44
Filed: 1973-12-12
Abstract: 1463820 Linkwork BRITISH LEYLAND UK Ltd 12 March 1975 [12 Dec 1973 2 March 1974] 57900/73 and 9518/74 Heading F2K In a mechanism for converting reciprocation of a member 9 into intermittent alternating tripped rocking motion of two twin rocker members 2, 16, the rocker 2 is fast on a shaft 1 and arranged facing the rocker 16 which is mounted on a spindle 11 of the reciprocatory member 9, the shaft 1 being journalled in a carrier (not shown) on which the member 9 is mounted for reciprocating movement towards and away from the shaft 1. The rocker 2 includes a pair of downwardly extending arms 3 which are formed with abutment faces 7, 13 which during operation positively position its rocking movement by respective engagement with faces 8, 15 on the reciprocating member 9, the arms 3 additionally having pins 5, 18 extending therefrom which alternatively engage to tilt and interlock the rocker 16 in one or other of its rocked positions. The rocker 16 has spring loaded latches 12, 19 which alternatively engage and tilt the rocker 2. The mechanism is arranged to continuously complete a cycle in which the rocker 2 is tilted alternatively first in one direction and then in the other on consecutive upward strokes of the reciprocating member 9, whilst the rocker 16 is similarly tilted first in one direction and then the other on consecutive downward strokes of the member 9. In operation, upward movement of the reciprocating member 9 from its position in Fig. A to Fig. B lifts the rocker 16 which via latch 12 tilts the rocker 2 until its arm 3 abuts the member 9 via faces 13, 14, the pin 5 being then positioned below a face 15 on the rocker 16 such that the following -downward movement of the member 9 causes the rocker 16 to trip on the pin 5 to tilt to the position in Fig. C, in which position the rocker 16 is interlocked on pins 5, 18 with its other latch 19 engaging the rocker 2. The next upward movement of the reciprocating member 9 from its position in Fig. C to Fig. D lifts the rocker 16 which via the latch 19 tilts the rocker 2 until its other arm 3 abuts the member 9 via faces 7, 8, the pin 18 being then positioned below a face 24 on the rocker 16 such that the following downward movement of the member 9 causes the rocker 16 to trip on the pin 18 to tilt back to the starting position in Fig. A thereby fully completing one cycle. A spring latch 20-23, or an overcentre spring-loaded toggle device (Fig. E, not shown), serves to hold the rocker 2 after it has been tilted to either of its rocked positions (Fig. D for example). Figs. A<SP>1</SP> to D<SP>1</SP> (not shown) illustrate a similar mechanism with slightly modified rockers &c. The mechanism may be used in a transfer machine in which a workpiece carrier incorporates such a mechanism whereby the reciprocating movement of member 9 is derived from lowering the carrier towards a work station and the resultant tilting movement of the rocker 2 to each of its rocked positions respectively operates a workpiece holder to hold or release a workpiece.