Method and apparatus for synchronizing a vehicle lift
AssigneeDelaware Capital Formation, Inc.
InventorsSteven D. Green, David P. Porter
Life of this patent
Estimating the term…
Abstract
A vehicle lift control maintains multiple points of a lift system within the same horizontal plane during vertical movement of the lift engagement structure by synchronizing the movement thereof. A vertical trajectory is compared to actual positions to generate a raise signal. A position synchronization circuit synchronizes the vertical actuation of the moveable lift components by determining a proportional-integral error signal.
Claims73
A controller for a vehicle lift, said vehicle lift having a first pair formed of a first vertically moveable superstructure and a second vertically moveable superstructure, each of said first and second vertically moveable superstructures having respective vertical positions which vary when said first and second vertically moveable superstructures are respectively moved, said controller comprising:
- a. an interface configured to receive a first position signal indicative of the vertical position of said first vertically moveable superstructure and a second position signal indicative of the vertical position of said second vertically moveable superstructure;
- b. a position synchronization circuit responsive to said first and second position signals and operably configured to synchronize vertical actuation of said first and second vertically moveable superstructures.
A control system for a vehicle lift, said vehicle lift having a first pair formed of a first vertically moveable superstructure and a second vertically moveable superstructure, said control system comprising:
- a. a first position sensor operable to sense a vertical position of the first vertically moveable superstructure;
- b. a second position sensor operable to sense a vertical position of the vertically moveable superstructure;
- and
- c. a position synchronization circuit responsive to the first and second position sensors and operably configured to synchronize vertical actuation of the pair of the first and second posts.
The controller of claim 26, further comprising a raise circuit responsive to said first and second position signals and to said vertical trajectory signal and operably configured to generate a first raise signal for said first vertically moveable superstructure and to generate a second raise signal for said second vertically moveable superstructure.
A hydraulic fluid control system for a vehicle lift comprising:
- a. at least one source of hydraulic fluid;
- b. a first hydraulic actuator configured to move a first vertically moveable superstructure, said first hydraulic actuator being in fluid communication with said at least one source of hydraulic fluid;
- c. a second hydraulic actuator configured to move a second vertically moveable superstructure, said second hydraulic actuator being in fluid communication with said at least one source of hydraulic fluid;
- d. a first proportional flow control valve interposed between said at least one source of hydraulic fluid and said first hydraulic actuator;
- e. a second proportional flow control valve interposed between said at least one source of hydraulic fluid and said second hydraulic actuator;
- f. said first proportional flow control valve and said second proportional flow control valve each being independently controllable relative to each other;
- and
- g. a controller connected to said first and second proportional flow control valves for controlling flow of said hydraulic fluid to said first and second hydraulic actuators.
A hydraulic fluid control system for a vehicle lift comprising:
- a. a first hydraulic actuator configured to move a first vertically moveable superstructure, said first hydraulic actuator being in fluid communication with a source of hydraulic fluid associated with said first hydraulic actuator;
- b. a first pump having a first discharge, said first discharge being in fluid communication with said first hydraulic actuator;
- c. a second hydraulic actuator configured to move a second vertically moveable superstructure, said second hydraulic actuator being in fluid communication with an associated source of hydraulic fluid;
- d. a second pump having a second discharge, said second discharge being in fluid communication with said second hydraulic actuator;
- and
- e. a controller connected to said first and second pumps for controlling the respective speeds of said first and second pumps variably, whereby flow of said hydraulic fluid to said first and second hydraulic actuators is controlled.
A controller for a vehicle lift, said vehicle lift having a first vertically moveable superstructure and a second vertically moveable superstructure, each of said first and second vertically moveable superstructures having respective vertical positions which vary when said first and second vertically moveable superstructures are respectively moved, said controller comprising:
- a. an interface configured to receive a first position signal indicative of the vertical position of said first vertically moveable superstructure and a second position signal indicative of the vertical position of said second vertically moveable superstructure;
- b. a raise circuit responsive to said first and second position signals and to a vertical trajectory signal and operably configured to generate a first raise signal for said first vertically moveable superstructure and to generate a second raise signal for said second vertically moveable superstructure.
A vehicle lift having a first pair formed of a first vertically moveable superstructure and a second vertically moveable superstructure, each of said first and second vertically moveable superstructures having respective vertical positions which vary when said first and second vertically moveable superstructures are respectively moved, said vehicle lift comprising:
- a. a first circuit operably configured to generate a first position signal indicative of the vertical position of said first vertically moveable superstructure;
- b. a second circuit operably configured to generate a second position signal indicative of the vertical position of said second vertically moveable superstructure
- c. a third circuit operably configured to generate a first raise signal for said first vertically moveable superstructure and to generate a second raise signal for said second vertically moveable superstructure, said first and second raise signals respectively being functions of said first and second position signals and a vertical trajectory signal.
A controller for a vehicle lift, said vehicle lift having a first pair formed of a first vertically moveable superstructure and a second vertically moveable superstructure, each of said first and second vertically moveable superstructures having respective vertical positions which vary when said first and second vertically moveable superstructures are respectively moved, said controller comprising:
- a. a first feedback control loop operably configured to command said first and second vertically moveable superstructures to a vertical trajectory;
- and
- b. a first differential feedback control loop operably configured to synchronize movement of said first and second vertically moveable superstructure.
A vehicle lift comprising:
- a. a first vertically moveable superstructure having a variable vertical position;
- b. a second vertically moveable superstructure having a variable vertical position;
- c. a controller operably configured to generate a vertical trajectory signal for said first and second vertically moveable superstructures.
A vehicle lift comprising:
- a. a first vertically moveable superstructure having a variable vertical position;
- b. a second vertically moveable superstructure having a variable vertical position;
- c. a controller operably configured to synchronize vertical actuation of said first and second vertically moveable superstructures by determining a proportional-integral error signal relative to the respective vertical positions of said first and second vertically moveable superstructures.
A controller for a vehicle lift, said vehicle lift having a first pair formed of a first vertically moveable superstructure and a second vertically moveable superstructure, each of said first and second vertically moveable superstructures having respective vertical positions which vary when said first and second vertically moveable superstructures are respectively moved, said controller comprising:
- a. an interface configured to receive a first position signal indicative of the vertical position of said first vertically moveable superstructure and a second position signal indicative of the vertical position of said second vertically moveable superstructure;
- and
- b. a first circuit operably configured to generate a vertical trajectory signal for said first and second vertically moveable structures
The controller of claim 73, wherein the controller is operably configured to synchronize vertical actuation of said first pair by determining a first pair proportional-integral error signal relative to the respective vertical positions of said first and second vertically moveable superstructures and to synchronize vertical actuation of said second pair by determining a second pair proportional-integral error signal relative to the respective vertical positions of said third and fourth vertically moveable superstructures.
Dependencies are inferred from the claim text.