Pallet sensor for lift truck
First Claim
1. A system for staging a fork lift with a pallet, wherein the fork lift has load wheels carried by forks and a lift system for extending the wheels away from and retracting the wheels toward bottoms of the forks to raise and lower the forks, the pallet has top and bottom decks defining passages therebetween and the bottom deck has at least one opening therethrough in communication with the passages, and the forks and load wheels are extendible into the pallet passages to lift the pallet upon extension of the wheels away from the bottoms of the forks, said system comprising sensor means carried on at least one of the forks for detecting the positions of the load wheels with respect to the at least one pallet bottom deck opening when the forks are extended into the pallet passages;
- and means responsive to said sensor means for generating a signal when the wheels are positioned to be extended away from the forks and through the at least one bottom deck opening to raise the forks and lift the pallet without contacting any portion of the bottom deck.
1 Assignment
0 Petitions
Accused Products
Abstract
A pallet sensing system, for a low lift pallet-type fork truck having load wheels extendible downwardly away from and retractable upwardly toward the forks to raise and lower the forks, is characterized by sensors for detecting proper alignment of the fork load wheels with respect to an opening in a bottom deck of a pallet. Upon the forks being extended into the pallet, the sensors disable lift controls of the truck to prevent the wheels from being extended away from the forks to lift the pallet until the sensors detect that the wheels are aligned for unobstructed passage through the bottom deck opening, whereupon the sensors enable the lift controls. The system prevents the pallet bottom deck from being broken by the wheels should an attempt be made to lift the pallet when the wheels are not positioned to pass freely through the opening, but would instead strike and break the bottom deck.
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Citations
20 Claims
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1. A system for staging a fork lift with a pallet, wherein the fork lift has load wheels carried by forks and a lift system for extending the wheels away from and retracting the wheels toward bottoms of the forks to raise and lower the forks, the pallet has top and bottom decks defining passages therebetween and the bottom deck has at least one opening therethrough in communication with the passages, and the forks and load wheels are extendible into the pallet passages to lift the pallet upon extension of the wheels away from the bottoms of the forks, said system comprising sensor means carried on at least one of the forks for detecting the positions of the load wheels with respect to the at least one pallet bottom deck opening when the forks are extended into the pallet passages;
- and means responsive to said sensor means for generating a signal when the wheels are positioned to be extended away from the forks and through the at least one bottom deck opening to raise the forks and lift the pallet without contacting any portion of the bottom deck.
- View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A system for staging a fork lift truck with a pallet, wherein the truck has a pair of horizontal forks, at least one load wheel carried by each fork and a lift system for moving the wheels away from and toward bottoms of the forks to raise and lower the forks, the pallet has top and bottom decks defining a pair of parallel passages therebetween and the bottom deck has an elongate opening extending transversely of and in communication with the passages, and the truck forks and load wheels are extendible into the pallet passages with the load wheels moved upwardly toward the forks, said system comprising sensor means carried on the forks for detecting when the forks are in the pallet passages and the positions of the load wheels with respect to the bottom deck opening;
- and means responsive to said sensor means for generating a signal when the wheels are positioned to be freely moved downwardly through the bottom deck opening to raise the forks and lift the pallet without contacting any portion of the bottom deck.
- View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16)
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17. A method of staging a fork lift with a pallet, wherein the fork lift has load wheels carried by forks and a lift system for moving the wheels away from and toward bottoms of the forks to raise and lower the forks, the pallet has top and bottom decks defining passages therebetween and the bottom deck has at least one opening in communication with the passages, and the forks and load wheels are extendible into the pallet passages to lift the pallet upon movement of the load wheels by the lift system downwardly from the forks, said method comprising the steps of extending the forks of the fork lift into the pallet passages with the load wheels moved toward the forks;
- sensing the positions of the load wheels with respect to the at least one bottom deck opening; and
generating a signal upon sensing that the load wheels are positioned to be moved freely downwardly through the at least one bottom deck opening to raise the forks and lift the pallet without contact of the load wheels with any portion of the bottom deck. - View Dependent Claims (18, 19, 20)
- sensing the positions of the load wheels with respect to the at least one bottom deck opening; and
Specification