GB1264468A - - Google Patents

Abstract

1,264,468. Turnstiles &c. TILTMAN LANGLEY Ltd. 20 Oct., 1969 [23 Oct., 1968], No. 50262/68. Heading E1J. [Also in Division G4] A mechanism for the control of the rotation or part rotation of a shaft 1 e.g. of a turnstile, comprises a cam-like formation 7 in the form of an equilateral triangle with convex sides and mounted for rotation with the shaft 1 and a first pawl 8 pivotally mounted at 8A and spring loaded at 9A through lever 9 and pin and slot connection 9A having an inner cam-engaging surface including a radially inwardly curved portion 8B joined to a straight portion 8D by a radially inward hook part 8C and when the shaft is in a locked position one of the rollers 7A at the apices of the formation 7 lies in the hook part 8C, and the next roller 7A in the direction of rotation (anticlockwise assumed) engages the end of the straight portion 8D; the arrangement allowing the shaft to be locked for rotation in one direction but free to rotate in the other direction, and these directions may be reversed by a mirror image reversing of the pawl 8 to the opposite side of the mechanism or providing a pawl 8 each side of the mechanism with means for putting one or other, out of action to selectively control the direction of rotation of the shaft, the first pawl 8 being released by the action of a bell crank lever 10 operating on the end of the bell-crank lever 9 or the pin 9B by such means as an electromagnet 11A operated by coin-freed mechanism mechanically or any other way to allow the shaft 1 to be rotated anticlockwise, and in a higher plane, a notched circular member 3 mounted for rotation with the shaft 1 and a second pawl 12 so engaging the circular member as to permit the initiation of rotation in either direction from a locked position by engagement in a wide gap 3B in the member 3, but so as to prevent reverse rotation after such initiation, by engagement in the notches 3A of member 3 until the pawl next engages in a gap 3B, the positions of the gaps 3B corresponding to the locked positions of the shaft. A semi rotary hydraulic damping mechanism 13 ensures that the turnstile will not overrun by its momentum if violently operated, and is actuated by a lever linkage 13A, 13C urged anticlockwise by a spring 13D. At the pivot 13B is a roller following the cam 7, whose lobes push the link 13A so there is damping resistance to the movement of the turnstile to its next-stop position 3B and when the lobe is retracting the spring 13D restores the damper. At the next stop position pawl 12 engages the gap 3B. To restore the damper to its unoperated condition there is provided a torque-restoring mechanism which comprises a cam-formed lever 14 with a spring 14B strongly urging the lever into contact with a roller 7A so that during the first half of the rotation movement energy is stored in the spring by the lever being rotated clockwise due to the action of roller 7A on an exponential curved part 14D of the lever 14 and the energy being returned to the lever during the second half of back movement so as to assist return movement of the lever, during which the roller moves along the straight edge 14C of the cam lever which reasserts itself on the formation 7 through roller 7A. Provision for counting the number of passages through the stile is provided (see Division G4).