The invention relates to wheeled carts with hinged doors subjected to vibration and, in particular, to improvements to make the doors less susceptible to vibration induced failure.
Wheeled carts for transporting packages in a fulfillment center or like warehouse or in a highway trailer can be subjected to vibration, either in a shaker to increase package density or on roadways with irregular surfaces. Doors, typically of steel tube frame and steel wire mesh construction, on such carts can fail at their hinges by vibration induced fatigue.
The invention provides hardware that can be retrofitted on existing cart doors to reduce the vibration amplitude in the doors and thereby alleviate the fatigue failure of the doors. The disclosed hardware is economical, easily installed and does not require extra effort when the doors are manually opened or closed. Ideally the hardware has provision for clamping on adjacent swinging door frame elements of a pair of double swing mounted doors. As disclosed, the hardware or bracketry can be identical for each door thereby saving cost, inventory and avoiding mistakes in assembly.
In the disclosed embodiment, the inventive brackets have fingers that interengage fingers of an opposed bracket to reduce relative vertical motion of the closed double doors, thereby reducing fatigue producing stress in the door hinge area.
A wheeled cart 10 with an upper pair of double doors 11, 12 and a lower pair of double doors 13, 14 is shown in
Door stabilizer units 26 of the invention are shown in
The stabilizer units or brackets 26 are assembled on the vertical free sections of the frame 18 remote from the hinges 16 of each of a pair of doors 11, 12 and 13, 14. The vertical position of one bracket 26 is higher than the adjacent other bracket 26 so that the clamping members 28 interfit with one another and permit only negligible relative vertical movement (e.g. ± 1/16 inch) of one door 11 or 13 to the other 12 or 14. The adjacent clamping members 28 are interengaged such that the clamping members, serving as fingers 28 of the two stabilizer units 26 are intermeshed.
It has been found that the stabilizer units 26, being interengaged when the respective double doors are closed as described, serve to greatly reduce vibration of the doors when the cart 10 is intentionally vibrated to increase the density of the packages on the cart or vibrated in highway transport, and the potential for fatigue failure at or around the door hinges 16.
It should be evident that this disclosure is by way of example and that various changes may be made by adding, modifying or eliminating details without departing from the fair scope of the teaching contained in this disclosure. The invention is therefore not limited to particular details of this disclosure except to the extent that the following claims are necessarily so limited.