Patent GB-1209809-A (GB)
Title: Improvements in or relating to a motion converting mechanism
IPC: F16H21/40
Filed: 1968-11-20
Abstract: 1,209,809. Mechanical presses. BATTELLE DEVELOPMENT CORP. 20 Nov., 1968 [21 Nov., 1967], No. 55138/68. Heading B5F. [Also in Divisions D1, F1 and F2] A linkage for converting continuous rotary motion of an input shaft 6 into oscillatory motion of a lever 11 about a fixed pivot 12, in which the output can be rendered inoperative without affecting the input, includes a pair of links 1, 3 pivoted together at 2, with the outer end of the link 1 connected to a crank-pin 26 of the shaft 6 and the outer end 39 of the link 3 pivoted at 10 to the output lever 11 which guides the end 39 along a substantially linear path, and two holding members 14, 15 (Fig. 1) only one of which can be operative at a time, such that when the member 14 is operative the link 3 is aligned with and movable along said linear path, and when the member 15 is operative the output lever 11 is held stationary. In Fig. 1, the link 1 is pivoted at 4 to a lever 7 which at one end engages the crank-pin 26 and at the other end is pivoted to an arm 8 having a fixed pivot 9. The holding members 14, 15 act magnetically when their respective coils 16, 17 are energized via a two-way switch 25. For an operative stroke of the output lever 11, the coil 16 need be energized only while the pivot-pin 4 moves from the position shown (Fig. 1) along a curve 22 to a point 20 lying on an extension 18 of the linear path of the link 3. For the rest of the travel of pin 4, forces in the linkage press the link 3 against the member 14, so that the switch 25 may be changed at any time during this remaining travel. The output member always completes a whole cycle of operation. Instead of the coils 16, 17, the members 14, 15 may be made operative by a permanent magnet in the form of a rotary horseshoe magnet (40), a pivotally mounted bar magnet (43), or an axially slidable bar magnet (45), (Figs. 3, 4, 5 respectively, not shown). Either one of the members 14, 15 may be replaced by a resilient member urging the link 3 or the lever 11 towards a fixed abutment (Figs. 6, 7, not shown). In Fig. 8, the holding members are formed by lugs 68, 69 on a rocker 66 controlled by electromagnets 75, 76 or by air jets (78, 79), (Fig. 9, not shown). In Fig. 10 (not shown), alternatively selectable suction nozzles (84, 85) form the holding members. Other arrangements of the lever 7, arm 8, and crank-pin 26 are described, to obtain different paths of travel of the pivot-pin 4 (Figs. 13-15, 17, not shown). In Fig. 16 (not shown) the link 1 is pivoted directly on the crank-pin. In Fig. 11, two linkages driven from a common pivot-pin 4 act on opposite ends of a floating output lever 55, the output connection 57 of which is one third of the way along it. Levers 11a, 11b of the two linkages have fixed pivots 12a, 12b. By energizing different combinations of the holding members, strokes of the connection 57 of 0, 1, 2 and 3 times a basic length can be obtained. In a variable force press, the connection 57 is coupled to a ram via a compression spring, so that the ram force depends on the spring compression and hence on the stroke of the linkage.