950,936. Conveyer installations. FISHER & LUDLOW Ltd. May 1, 1961 [Feb. 2, 1960; Dec. 22, 1960], Nos. 3715/60 and 44105/60. Heading B7L. In a conveyer installation in which article carriers 14, 15 are driven, to the left in Fig. 2, along a carrier track 12 by dogs 17 dependant from a driving element, e.g. a drain 13 running in a track 11, the dogs being in engagement with driving bars 19 on the carriers, a carrier drive disengaging element 22 is provided at one or more locations along the tracks, together with an actuating element arranged in advance of the carrier drive disengaging element and operably connected thereto such that when a carrier advances along the track 12 it engages the actuating element and thus displaces the associated element 22 into operative, i.e. drive disengaging position, so as to disconnect the drive to the advancing carrier next in rear to prevent a collision between the carriers, a carrier advance control member 41 being provided at the or each location, and mounted for pivotal movement about a vertical axis between locking and free positions in which it respectively locks its associated actuating element and thus the carrier drive disengaging element connected thereto in operative position or allows these elements to move to their inoperative positions, control member release means, e.g. a solenoid 51, Fig. 4, also being provided to displace the carrier advance control member 41 into its free position when actuated, the carrier advance control member when in its free position being adapted to engage with part of a carrier advancing along the track 12 and to be thereby pivoted into its locking position to retain the associated actuating element and drive disengaging element 22 in operative position until the control member release means is actuated. The assembly of an actuating element for a carrier drive disengaging element and a carrier advance control member is shown exploded in Fig. 6. The actuating element comprises a crank lever 31 pivoted at 36 to a bracket 38, which is fixed to the track 12. An L-shaped bar 34 is secured to the lever 21, its limb 35 projecting into the path of an oncoming carrier 14, which carrier moves the bar 34, and thus the lever 31 anticlockwise about the pivot 36, causing a connecting rod 29 to rotate a spindle 27 in a clockwise direction, the spindle 27 moving the carrier drive disengaging element 22, at the location next in rear along the conveyer, from its inoperative position shown in the right-hand side of Fig. 4, to its operative position shown in the left-hand side of Fig. 4. The carrier drive disengaging element comprises a cam portion 24 and a spring-loaded stop 25. When in its operative position the cam portion engages and lifts abutments 17a, Fig. 2, on the dogs 17, so that the dogs 17 clear the driving bar 19, which is held against the stop 25. The carrier advance control member 41, Fig. 6, is pivotally mounted at 42 on an arm 44, which is secured to the bracket 38, and is provided with en abutment roller 49, an abutment pin 54, and an arm 46, which is engaged by the article carriers 14, together with the limb 35, so that both are moved to the position shown in Fig. 7, where the roller 49 is engaged in an arcuate recess 50 in the lever 31 to lock the lever 31, and thus its associated carrier drive disengaging element 22 in their operative positions, whereby the next carrier 14 will be arrested by this element 22. The arm 46 and limb 35 remain in the position shown in Fig. 7 as the carrier 14 is moved along the conveyer and the carrier may then actuate a microswitch (not shown) situated along the track 12 to cause the solenoid 51, Fig. 4, to push on the abutment pin 54 and release the roller 49 from the recess 50, whereupon the arm 46 and limb 35 move back into the path of the next advancing carrier 14, as shown in the left-hand side of Fig. 4. The carrier drive disengaging element 22 is normally held in its inoperative position by a spring 56, Fig. 2, and when it is moved into its operative position a pivoted latch 57 falls and locks it therein until the next abutment 17a raises the latch 57 and releases the element 22. This ensures that the carrier 14 is not moved until a dog 17 has arrived in a position where it is able to take up the drive. The solenoid 51 may alternatively be controlled manually and may be operable from a position in rear of the location of the carrier advance control member so that an operator may control the discharge of the foremost carrier from a bank of carriers disposed one behind the other. The solenoid 51 may also act on the abutment pin 54 through a pivoted cranked lever (not shown). Specifications 819,343, 949,204 and 949,205 are referred to. Specifications 941,239, 949,206, 949,207 and 949,209 also are referred to in the Provisional Specifications.