GB265195A - Improvements in vehicle brakes - Google Patents

Abstract

265,195. Renaux, E. P. Jan. 29, 1926, [Convention date]. Blocks and shoes acting on drums; band.-An internal expanding brake wherein the brake band or other friction member is expanded by giving an equal radial movement to a number of equally spaced points on the band &c, comprises a pair of levers 34, 35. Fig. 1, pivoted at 33 and expanded by a cam 2 and a number of levers 40 mounted on fixed pivots 41. The ends of the levers 40 engage parts of the brake band 4 and intermediate points of the levers 34, 35. The band is anchored at an intermediate point in its length by a stop 7. The levers 34, 35 may also be provided with projections 39', 39<11> for applying pressure directly to parts of the band. The Specification, as open to inspection under Sect. 91 (3) (a) includes also the following subject-matter :-Fig. 2 (Cancelled) shows a brake wherein a series of cams 2 is arranged to engage a band 4, one or other end of which abuts against a fixed stop 7 according to the direction of rotation of the drum. The cams have toothed sectors 12 geared to a toothed ring 13 supported on rollers 14, actuation of the cams being effected by an arm 1 on one of them or by turning the ring directly. The arrangement is such that substantially equal pressures are applied to the several parts of the band taking into account the pressure due to the self-wrapping or winding action of the band. Instead of employing the toothed gearing, the cam arms may be linked together. Fig. 4 (Cancelled) shows a form comprising a series of shoes 4 each of which is anchored at 20 to a fixed plate by a link 18. A rotatable ring 15 guided for circular movement by engagement of concentric surfaces 23 with rollers on the pivots 20 has cam surfaces 48 for engagement with rollers on the pivots 28 of the shoes. Springs 25 connected to pins 27 adapted to abut on fixed pins 24 hold the shoes in the disengaged position. As shown in the lower part of Fig. 4, the shoes may comprise pairs 4<a>, 4<b>, hinged together by a link 30. The shoes 4b is anchored by the link 18b, but the end 28<a> of the link 18a contacts with but is not connected to the shoe 4a. Pressure is thus applied to both shoes of a pair by the cam surfaces 48 and the shoe 4<a> also applies pressure to the shoe 4<b>. A cam ring such as 15 may also be used for applying a brake band to a drum. This subject-matter does not appear in the Specification as accepted.