Patent GB-1236262-A (GB)
Title: Improvements relating to conveyors
Inventor: ROOKE SYDNEY WILLIAM
IPC: B61B10/02
Filed: 1968-04-10
Abstract: 1,236,262. Conveyers. SOVEX Ltd. 10 April, 1969 [10 April, 1968], No. 17301/68. Heading B7L. A conveyer comprises trolleys running on a guiding track, trolley propelling means, a trolley storage section, and means for selectively advancing trolleys through the storage section comprising at least one endless driving belt which engages at least one drive wheel mounted on the trolley with a predetermined degree of frictional resistance to rotation. The main track 1, Fig. 2, comprises two vertically spaced box-section rails 10, 16, the upper one 10 carrying a driving chain comprising links 11 carried on vertical wheels 12 and links 111 guided by horizontal wheels 13, each link 11 carrying a fixed pusher 14 and pivoted latch 15 which project from a slot in the lower side of rail 10 into the vicinity of the lower rail 16 which comprises a pair of opposed channel-shaped members 20. Each trolley comprises a longitudinal bar 17 having two pairs of wheels 18 mounted on horizontal axles 19 and a pair of wheels 22 mounted on a vertical axle 21 which projects from the top of the rail 16 and carries a roller 23 to engage the pusher 14. Guide rollers 25 mounted on vertical axles 24 attached to the bar 17 engage the lower opposed edges of the members 20, and the axles 24 also carry a bracket 26 which supports the load. The upper wheel 22 mounted on the vertical axle 21 is mounted over a large-diameter bush to provide a predetermined frictional resistance to rotation In the storage section, the trolley is disconnected from the chain, and the channel member 20 on one side of the track is omitted, the position of its vertical web being occupied by one flight 31 of an endless driving belt moving on edge against a backing plate 32, and engaging the upper wheel 22, the lower wheel 22 engaging the vertical portion of an L-shaped member 20 on the other side of the track. The wheels 18 on the same side of the track as the belt are free from any engagement, while the other wheels 18 engage the horizontal flange of member 20. If the trolley is free from any obstruction, the upper wheel 22 will not rotate and the trolley is advanced by the belt. When an obstruction is met, e.g. when the trolley joins a queue of trolleys, the upper wheel 22 will rotate and the trolley will stop. The lower wheel 22 may be omitted, Fig. 6 (not shown) lateral guidance being assisted by a space fitted in the angle of the L-shaped member 20. In a modification, Figs. 7 and 8 (not shown), the wheels 18 and 22 are mounted perpendicular to each other and at 45 degrees to the vertical so that part of the weight of the trolley provides driving pressure on the belt. In another modification, Figs. 9, 10, 11 (not shown), the outer edges of the wheels 18 are bevelled and the bevelled portion of the wheels engage a suitably inclined portion of guide member 20 producing a sideways driving pressure on the belt which runs on edge as in Fig. 5. The belt is provided with a number of projections (33) which, when the trolley is free, help to accelerate it to the speed of the chain, and when the trolley is queuing merely tilt it slightly. Release from the queuing section is effected by means of an escapement (4), e.g. in the form of a pair of alternately reciprocable pawls, Fig. 1 (not shown), which release the trolleys one or more at a time, the remainder of the trolleys then being advanced by the endless belt to provide more queuing space.