Abstract: A shock absorbing tow bar for connecting between a drive trolley and a load carrying trolley of a conveyor system. The tow bar includes a pair of tubes that reciprocate relative to each other. A plunger is located within a first of the tubes and attached to a second tube. Mounted on the plunger are a pair of brake surfaces that frictionally engage the first tube. The brake surfaces are biased toward the first tube by springs and the force applied to the brake surfaces is adjustable through an adjustment mechanism including a pair of wedges upon which the springs are located. An adjustment rod is joined with the adjustment mechanism and extends outwardly from the tow bar to allow an operator to adjust the friction produced by the brake surfaces without disassembly of the tow bar.

Abstract: A shock absorbing tow bar for connecting between a drive trolley and a load carrying trolley of a conveyor system. The tow bar includes a pair of tubes that reciprocate relative to each other. A plunger is located within a first of the tubes and attached to a second tube. Mounted on the plunger are a pair of brake surfaces that frictionally engage the first tube. The brake surfaces are biased toward the first tube by springs and the force applied to the brake surfaces is adjustable through an adjustment mechanism including a pair of wedges upon which the springs are located. An adjustment rod is joined with the adjustment mechanism and extends outwardly from the tow bar to allow an operator to adjust the friction produced by the brake surfaces without disassembly of the tow bar.

Abstract: A shock absorbing tow bar for connection between the accumulating trolley and load carriage of a power and free conveyor system is disclosed. The tow bar includes one component that is connectable to the accumulating trolley and another that is connectable to the intermediate trolley of the load carriage. Limited relative shifting is permitted between the components of the tow bar. Moreover, the components are threadably intercoupled so that such relative shifting requires a screwing or unscrewing action that serves to cushion movement between the accumulating trolley and load carriage.

Abstract: A shock absorbing tow bar for connection between the accumulating trolley and load carriage of a power and free conveyor system is disclosed. The tow bar includes one component that is connectable to the accumulating trolley and another that is connectable to the intermediate trolley of the load carriage. Limited relative shifting is permitted between the components of the tow bar. Moreover, the components are threadably intercoupled so that such relative shifting requires a screwing or unscrewing action that serves to cushion movement between the accumulating trolley and load carriage.

Abstract: A shock absorbing tow bar for connection between the accumulating trolley and load carriage of a power and free conveyor system is disclosed. The tow bar includes one component that is connectable to the accumulating trolley and another that is connectable to the intermediate trolley of the load carriage. Limited relative shifting is permitted between the components of the tow bar. Moreover, the components are threadably intercoupled so that such relative shifting requires a screwing or unscrewing action that serves to cushion movement between the accumulating trolley and load carriage.

Abstract: A shock absorbing tow bar for connection between the accumulating trolley and load carriage of a power and free conveyor system is disclosed. The tow bar includes one component that is connectable to the accumulating trolley and another that is connectable to the intermediate trolley of the load carriage. Limited relative shifting is permitted between the components of the tow bar. Moreover, the components are threadably intercoupled so that such relative shifting requires a screwing or unscrewing action that serves to cushion movement between the accumulating trolley and load carriage.

Abstract: A stop mechanism for detaching a conveyor trolley from a drive system which normally drives the trolley along a conveyor track. A ramp can be moved into the path of a trolley dog so that the trolley dog moves upwardly along an inclined ramp surface to disengage the trolley dog from a drive dog carried by a driven chain of the conveyor system. The actuating mechanism for the ramp includes a pivotal cam plate actuated by a power cylinder. A cam slot in the cam plate receives a cam roller connected with a guide link which moves in a vertical guide slot. The guide link is connected with the ramp to move it up and down under the control of the actuating cylinder.

Abstract: A shock absorbing tow bar for connection between the accumulating trolley and load carriage of a power and free conveyor system includes one component that is connectable to the accumulating trolley and another that is connectable to the intermediate trolley of the load carriage. Limited relative shifting is permitted between the components of the tow bar. Moreover, the components are threadably intercoupled so that such relative shifting requires a screwing or unscrewing action that serves to cushion movement between the accumulating trolley and load carriage.

Abstract: A cushioned tow bar for connecting a drive trolley to a load carriage in a power and free conveyor system includes a particulate shock absorber with a damping chamber which is partially filled with particulate material, such as small ball bearings, which act to dampen the movement of a piston through the damping chamber. The damping chamber comprises a portion of a sleeve which includes a threaded end cap which mates with threads on an open end of the sleeve. The threads in the sleeve extend along the longitudinal axis of the sleeve to an extent which allows the end cap to be threadably adjusted, changing the portion of the sleeve forming the damping chamber, and thus adjusting the cushioning effect of the tow bar.

Abstract: The present invention is directed to a seal crossover system which includes two seal plates adjacent to slot crossover portions of separate respective conveyor loops as they diverge (or converge) past a switch in a power and free conveyor system. The seal plates are driven by respective pneumatic cylinders which are pneumatically linked to a switch cylinder such that the seal plates are automatically extended or retracted depending upon the condition of the switch. Thus a respective slot crossover portion of each conveyor loop is selectively and alternately sealed or opened to allow unimpeded passage of a load carriage and a drive trolley, respectively.

Abstract: A power and free conveyor transfer system includes a number of drive trolleys operating within a free track and being selectively propelled by endless drive chains within a vertically aligned power track. Each drive trolley includes a trolley housing body to which are rigidly attached a pair of downwardly extending lateral arms, each with a rearward facing drive surface. A pivotable drive member is attached to the front end of the trolley housing and extends backward and downward between the lateral arms with a drive dog forming a portion thereof. The drive trolley design facilitates transfer of each drive trolley between non-synchronous delivering and receiving power tracks in a conveyor transfer zone. Within the transfer zone, the delivering and receiving power tracks are at different elevations and approach each other from a relatively large angle to minimize the potential for mechanical interference or jamming.

Abstract: An automatic stabilizing unit for a free trolley and a load carriage in an inverted power and free conveyor system is connected to the free trolley. The stabilizing unit includes a stabilizer actuator which extends above a free track containing the free trolley from beneath the floor of a building which houses the conveyor, and a stabilizing gear mounted on the load carriage. At locations in an assembly plant, such as robotic welders or riveting stations where load shifting tolerances are critical, there must be additional stabilization of the load carriage. At these locations, stabilizing rails are positioned on top of the free track in line with stabilizing trucks on the stabilizing actuator. When the stabilizing trucks contact the rails, the trucks are urged upward, pushing an attached piston upward against a spring which causes a pair of stabilizing wheels on the stabilizing gear to rotate downward into contact with the factory floor, thus stabilizing the carriage only when needed.

Abstract: A self-adjusting shock absorbing carrier for inverted powder and free conveyors includes a telescoping tubular main carrier frame with a support trolley connected to a rear end of an outer tube and a drive trolley connected to a front end of an inner tube of the frame. Tubular friction pads are positioned between the inner and outer tubes and located so that the weight of a load supported by the main frame determines the frictional engagement between the inner and outer tubes and the friction pads. When the drive trolley is abruptly engaged by a pusher dog on a conveyor drive chain or when the drive trolley is abruptly braked, the shock generated thereby is dissipated in frictional resistance to relative movement between the inner and outer tubes to thereby cushion startup and braking of the carrier.

Abstract: A floor conveyor junction seal gap closure includes a closure member pivotally mounted on and resiliently connected to a bracket extending upward from a conveyor switch mechanism. The floor conveyor includes a main line and a diverging branch line, both adapted to carry load trolleys connected by posts to load carriers positioned above the floor level. Floor slots are provided to clear the connection posts, and the slots are closed by split resilient seals. The seals are opened by the connection posts moving through them and resiliently close behind the posts. A seal gap is formed at the area of divergence of the branch slot from the main slot. The closure plate is positioned below the seal gap to normally close the seal gap. The resilient mounting of the closure plate allows it to be deflected to allow a connection post to pass through the seal gap and afterward returns the closure plate to its neutral position to close the seal gap.

Abstract: A shock absorbing load carrier for an inverted power and free conveyor includes a telescoping main frame formed by a leading inner tubular member received in a trailing outer tubular member with a shock absorbing arrangement engaged therebetween. A drive trolley is connected to a front end of the inner member, and a support trolley is connected to a rear end of the outer member. A load supporting framework is mounted on the outer member for fastening a load to be carried thereon. The shock absorbing arrangement includes a damping chamber formed in the inner member and a piston member connected by a rod to the outer member. A particulate damping material, such as a quantity of ball bearings is positioned in the damping chamber. Relative movement of the inner and outer members caused by abrupt startup or braking of the drive trolley is retarded by resistance to movement of the piston through the damping material, thereby reducing the transfer of shocks from the drive trolley to the load.

Abstract: A center link pusher dog assembly for power and free conveyors includes a pusher dog member with a mounting base and a pusher dog projection upstanding therefrom. The mounting base has depending lugs and a rear shoulder to engage an abutment formed by a reduced central area of a center link of a conveyor chain. A bore through the pusher dog member recevies a bolt for clamping a center link between the pusher dog member and a conventional chain support type of power trolley. The lugs engage upstanding teeth on a mounting end of the power trolley and side walls of the center link to fix the longitudinal position of the pusher dog member relative to the power trolley and the center link and to fix its lateral position relative to the center link.

Abstract: A positive retraction trolley stop mechanism is provided for a power and free conveyor system having a trolley member driven along a track. A depending trolley dog, engaged by drive dogs on a drive mechanism to push the trolley along the track, is movable between upper and lower positions for disengagement and engagement with drive dogs. The stop mechanism includes a pivotal stop arm which is pivoted to an upper position to engage a trolley dog on a trolley to be stopped and supported there by a cam member which is pivoted by a piston and cylinder. The cam member is pivoted out from under the stop arm to release the stop arm to assume its lower non-braking position. A one way or lost motion link is connected between cranks on a cam shaft and a stop arm axle to positively pull the stop arm to its non-braking position. The lost motion link is connected to the cam crank by a link connector which slidably engages a slot in the ink.

Abstract: A trolley stop assembly is provided for use with an inverted power and free conveyor system having a trolley member driven along a track. A depending trolley dog is engaged by drive dogs on a drive mechanism for pushing the trolley along the track and is movable between upper and lower positions for disengagement and engagement with the drive dogs. The assembly includes a stop arm pivotally mounted within the conveyor system for pivoting about a horizontal axis. Provisions are made for lifting the stop arm into an upper position to engage a portion of a trolley dog on a trolley to be stopped to lift the trolley dog out of possible engagement with the drive dogs. The stop arm includes an upper cam surface with an abutment portion for braking the trolley by mating with a portion of the trolley dog. An actuator mechansim includes a cam engageable with the stop arm to pivot same between upper and lower positions. The cam member is actuated by a piston and cylinder arrangement positioned on a side of the assembly.

Abstract: An apparatus for selectively storing a thin tray or sheet in an elongate storage location, and retrieving trays therefrom, includes a tray extractor and a transport assembly. The tray extractor comprises a tray engagement mechanism and a tray linear movement actuator. The tray engagement mechanism operates as a hand to selectively grip or release trays which are being handled by the apparatus. The tray linear movement actuator acts as an arm to position the tray engagement mechanism and, when operated, to move an engaged tray. The tray linear movement actuator comprises a linear movement link and pulley arrangement which moves an engaged tray along a linear path of motion, and which maintains the tray engagement mechanism in a selected orientation with respect to that path of movement. The tray engagement mechanism comprises an X-shaped scissors mechanism having a plurality of jaws thereon. Scissors motion of the mechanism opens and closes the pairs of jaw members to selectively engage or disengage a tray.