GB190505375A - A New or Improved Device for Preventing Lifts, Colliery Cages and the like, Falling, in the Event of the Cable Breaking, or Control of the Brakes being Lost. - Google Patents

Abstract

5375. Walters, W. March 14. Safety-suspending or retaining apparatus for lifts, colliery cages, or the like. Fig. 1 shows a sectional elevation and Fig. 3 a plan of a lift or colliery cage with one form of the device attached, and Fig. 6 a bottom plan of a brake mechanism for the same. Slidably mounted between blocks a<2>, a<3> and rollers a<4>, a<5> on the top of the lift are two bars a, a', shaped so as to form a space d through which passes a wedge piece e which is connected to the lifting- cable g. Springs i, i<1> bear against the ends of the bars a, a' and tend to push them forward into the position shown in Fig. 1. Normally, the weight of the lift on the piece e causes it to move upwards into the space h<2>, thus drawing the bars a, a<1> inwards as in Fig. 3. In the event of the cable breaking, the piece e falls into the recess f and the bars a, a<1> are forced outwards so as to engage the rack or its equivalent j and arrest the travel of the lift. In a modification, the rack j is made in the form of a sinuous curve and the bars a, a<1> are liberated by the occupant of the lift pulling downwards suitably-placed spring-pressed pins. The above device may also be used in combination with the brake mechanism shown in Fig. 6, which, when applied, momentarily checks the lift and thereby allows the bars a, a<1> to come into operation. The brake comprises two pairs of levers k, kl, loosely connected in pairs at n, n<1>, and pivoted to the bottom of the lift at l, l<1>, the outer ends being furnished with brake blocks m<2> designed to engage the sides of the rack &c. j. To operate the brake, the occupant moves a lever which pushes the wedge o to the right, thus moving the levers k, k<1> outwards, which causes the rack j to be gripped by the brake shoes m<2>.