US 6,206,170 B1 · Control system for a tilt tray sorter

Abstract

A speed control system for a sorting conveyor for transporting objects and unloading objects at one or more unloading stations adjacent the conveyor. Each of the tilting conveyor carts includes a trailer frame base, a carrying tray for holding the objects and a two-axis tiltable support apparatus for supporting the carrying tray above the trailer frame base and for allowing tilting of the carrying tray towards at least one side of the conveyor to unload objects into unloading stations on at least one side of the conveyor. The conveyor system includes a plurality of selectively energized linear induction motors for driving the train along the conveyor track. A speed control system including a fixed-frequency, variable-voltage transformer is connected to a portion of the linear induction motors for varying the speed of the train.

Claims14

Dependent claims

A speed control system for a package sorting conveyor system of the type having at least one conveyor cart movable along a continuous conveyor track and at least one unloading station and a plurality of selectively energized linear induction motors for driving said train along said conveyor track, said speed control system comprising:

(a) an electrical power supply;
(b) a transformer connected to said power supply;
(c) a preselected number of said linear induction motors connected directly to said power supply;
(d) a preselected number of linear induction motors connected to said transformer;
and
(e) a voltage controller connected to said transformer for receiving a speed setting input signal from a speed sensor and sending a variable voltage signal to said transformer to vary its voltage output, thereby maintaining said cart substantially at a predetermined speed in response to said speed sensor input signal for controlling the speed of said cart.

3 more elements

A package sorting conveyor system of the type having at least one conveyor cart movable along a continuous conveyor track and at least one unloading station, said conveyor system comprising:

(a) a conveyor track;
(b) a train of conveyor carts connected end-to-end and movable along said conveyor track;
(c) a plurality of selectively energized linear induction motors for driving said train along said conveyor track;
and
(d) a speed control system, wherein said speed control system includes control means for maintaining said train substantially at a predetermined speed in response to an output signal representative of the speed of said train from a speed sensor, said speed sensor being adapted to detecting the speed and providing said output signal to said speed control system, and a fixed-frequency, variable-voltage transformer connected to a portion of said linear induction motors for varying the speed of said train, said speed control system including:
(i) an electrical power supply;
(ii) a transformer connected to said power supply;
(iii) a preselected number of said linear induction motors connected directly to said power supply;
(iv) a preselected number of linear induction motors connected to said transformer;
and (v) a voltage controller connected to said transformer for receiving a speed setting input signal and sending a variable voltage signal to said transformer to vary its voltage output, thereby controlling the speed of said cart.

7 more elements

Dependencies are inferred from the claim text.

Control system for a tilt tray sorter

Life of this patent

Control system for a tilt tray sorter

Life of this patent

Abstract

Claims14