US 7,681,272 B2Granted

Counterbalance assembly for a fold out ramp

AssigneeLift-U, Division of Hogan Mfg., Inc.

InventorsDonald Morris, David Johnson

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Abstract

A counterbalance for a ramp assembly includes a chain assembly and a spring assembly. The spring assembly includes a spring and first and second spring fittings. The first spring fitting restrains a first end of the spring when the ramp portion is between a neutral position and the stowed position and moves the first end of the spring toward a second end of the spring when the ramp portion moves from the neutral position toward the deployed position. The second spring fitting is spaced from the first spring fitting and restrains the second end of the spring when the ramp portion is between the neutral position and the deployed position. The second spring fitting moves the second end of the spring toward the first end of the spring when the ramp portion moves from the neutral position toward the stowed position.

Claims20

Dependent claims

A counterbalance for a ramp assembly, the ramp assembly having a ramp portion operatively coupled for reciprocating motion between a stowed position and a deployed position, the counterbalance comprising:

a) a chain assembly, comprising:
(i) a chain portion operatively coupled to the ramp portion to move along a path in a first direction when the ramp portion moves toward the stowed position, and in a second direction when the ramp portion moves toward the deployed position;
and
(ii) a rod coupled to the chain portion;
and
(b) a spring assembly, comprising:
(i) a spring;
ii) a first spring fitting restraining a first end of the spring when the ramp portion is between a neutral position and the stowed position and moving the first end of the spring toward a second end of the spring when the ramp portion moves from the neutral position toward the deployed position;
and
(iii) a second spring fitting spaced from the first spring fitting, the second spring fitting restraining the second end of the spring when the ramp portion is between the neutral position and the deployed position and moving the second end of the spring toward the first end of the spring when the ramp portion moves from the neutral position toward the stowed position.

7 more elements

A drive assembly for reciprocating a movable ramp portion of a ramp assembly between a stowed position and a deployed position, the drive system comprising:

(a) a motor;
(b) a drive shaft operably coupled to the motor and to the ramp portion so that rotation of the drive shaft in a first direction drives the ramp portion toward the stowed position, and rotation of the drive shaft in a second direction drives the ramp portion toward the deployed position;
(c) a chain assembly, comprising:
(i) a chain portion operatively coupled to the drive shaft to move along a path in a first direction when the ramp portion moves toward the stowed position, and in a second direction when the ramp portion moves toward the deployed position;
and
(ii) a rod coupled to the chain portion;
and
(d) a spring assembly, comprising:
(i) a spring;
(ii) a first spring fitting restraining a first end of the spring when the ramp portion is between a neutral position and the stowed position and moving the first end of the spring toward a second end of the spring when the ramp portion moves from the neutral position toward the deployed position;
and
(iii) a second spring fitting spaced from the first spring fitting, the second spring fitting restraining the second end of the spring when the ramp portion is between the neutral position and the deployed position and moving the second end of the spring toward the first end of the spring when the ramp portion moves from the neutral position toward the stowed position.

9 more elements

A ramp assembly, comprising:

(a) a ramp portion operatively coupled to the vehicle for reciprocating motion between a stowed position and a deployed position;
(b) a chain assembly, comprising:
(i) a chain portion operatively coupled to the ramp portion to move along a path in a first direction when the ramp portion moves toward the stowed position, and in a second direction when the ramp portion moves toward the deployed position;
and
(ii) a rod coupled to the chain portion;
and
(c) a spring assembly, comprising:
(i) a spring;
(ii) a first spring fitting restraining a first end of the spring when the ramp portion is between a neutral position and the stowed position and moving the first end of the spring toward a second end of the spring when the ramp portion moves from the neutral position toward the deployed position;
and
(iii) a second spring fitting spaced from the first spring fitting, the second spring fitting restraining the second end of the spring when the ramp portion is between the neutral position and the deployed position and moving the second end of the spring toward the first end of the spring when the ramp portion moves from the neutral position toward the stowed position.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/114,647Filed 2 May 2008 · us provisional application
Priority: 4 May 2007
Published: US 2008/0273956 A16 Nov 2008
Granted: 23 Mar 2010
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

E01D 19/00
Structural or constructional details of bridges
A61G 3/061
Transfer using ramps, lifts or the like: using ramps
A61G 3/067
Transfer using ramps, lifts or the like: with compartment for horizontally storing the ramp or lift
B60P 1/433
Using a loading ramp mounted on the vehicle: the loading floor or a part thereof being movable to form the ramp