Lift assembly with load cells

Patent metadata

Field	Value
Publication number	US-10544018-B2
Application number	US-201715716830-A
Country	US
Kind code	B2
Filing date	Sep 27, 2017
Priority date	Nov 22, 2013
Publication date	Jan 28, 2020
Grant date	Jan 28, 2020

Abstract

A lift assembly comprises a base, a drive mechanism, a flexible drive element extending from the drive mechanism along a fleet axis, and a sheave directing the drive element from the fleet axis to an output axis. The sheave is coupled to the base at a first sheave mount aligned with the fleet axis. The assembly can further include a second sheave mount aligned with the fleet axis and configured to be coupled to the sheave to allow the sheave to be de-coupled from the first sheave mount and coupled to the second sheave mount, resulting in substantially no change in a fleet angle of the fleet axis. Preferably, the sheave is positioned on a first side of the fleet axis when coupled to the first sheave mount, and the sheave is positioned on a second side of the fleet axis (e.g., opposite the first side) when coupled to the second sheave mount.

First claim

What is claimed is:

1. A lift assembly comprising:
a base;
a drum including a longitudinal axis;
a flexible drive element driven by the drum and extending from the drum along a fleet axis; and
a sheave directing the drive element from the fleet axis to a first output axis different than the fleet axis when the sheave is coupled to the base in a first orientation relative to the base and the sheave is configured to be coupled to the base in a second orientation relative to the base different than the first orientation;
wherein in the first orientation, the sheave directs the drive element from the fleet axis to the first output axis, and
wherein to couple the sheave to the base in the second orientation, the sheave is repositioned relative to the base to an opposing side of the fleet axis to direct the drive element from the fleet axis to a second output axis different than the first output axis.

2. A lift assembly as claimed in claim 1 , wherein the sheave is coupled to the base at a first sheave mount in the first orientation aligned with the fleet axis and the lift assembly further comprises a second sheave mount aligned with the fleet axis, the second sheave mount being configured to be coupled to the sheave to thereby allow the sheave to be de-coupled from the first sheave mount and coupled to the second sheave mount to position the sheave in the second orientation, the second sheave mount being positioned such that coupling of the sheave to the second sheave mount results in substantially no change in a fleet angle of the fleet axis.

3. A lift assembly as claimed in claim 2 , wherein the first sheave mount is offset relative to a rotational axis of the sheave in a direction that has a component along the longitudinal axis of the drum, wherein the rotational axis of the sheave is positioned on a first side of the fleet axis in the direction along the longitudinal axis when the sheave is coupled to the first sheave mount, and wherein the rotational axis of the sheave is positioned on a second side of the fleet axis in the direction along the longitudinal axis when the sheave is coupled to the second sheave mount.

4. A lift assembly as claimed in claim 2 , wherein the fleet axis substantially bisects the first and second sheave mounts in the direction along the longitudinal axis.

5. A lift assembly as claimed in claim 2 , wherein the first and second sheave mounts are positioned on first and second sheave plates, respectively, and wherein the first and second sheave plates are substantially parallel to the first output axis and the second output axis.

6. A lift assembly as claimed in claim 5 , wherein the first sheave plate is positioned at least partially directly below the second sheave plate.

7. A lift assembly as claimed in claim 2 , wherein the first and second sheave mounts are each movable relative to the base.

8. A lift assembly as claimed in claim 1 , wherein the sheave is coupled to a sheave mount by a sheave bracket that positions the sheave with an edge of the sheave aligned with the fleet axis in both the first and second orientations.

9. A lift assembly as claimed in claim 1 , wherein the base includes a load plate assembly having a first sheave plate and a second sheave plate, and wherein the sheave is coupled to the first sheave plate in the first orientation, and wherein the sheave is coupled to the second sheave plate in the second orientation.

10. A lift assembly as claimed in claim 1 , wherein the sheave is moveable about a rotational axis relative to the base, and wherein the sheave is pivotably coupled to the base about a pivot axis.

11. A lift assembly comprising:
a frame;
a drum supported by the frame; and
a sheave selectively couplable to a portion of the frame in a first orientation and a second orientation, the sheave configured to direct a flexible drive element from the drum along a fleet axis to a first direction when the sheave is in the first orientation, the sheave configured to direct the flexible drive element from the drum along the fleet axis to a second direction different than the first direction when the sheave is in the second orientation;
wherein the first orientation is defined by a rotational axis of the sheave being positioned at a first location relative to the portion of the frame and the rotational axis being on a first side of the fleet axis, and wherein the second orientation is defined by the rotational axis of the sheave being positioned at a second location different than the first location relative to the portion of the frame and the rotational axis being on a second side of the fleet axis.

12. A lift assembly as claimed in claim 11 , wherein the portion of the frame is a load plate assembly, and wherein the sheave is selectively coupled to a first sheave plate of the load plate assembly when in the first orientation, and wherein the load plate assembly is configured to sense a first horizontal load acting on the first sheave plate.

13. A lift assembly as claimed in claim 12 , wherein the load plate assembly includes a second sheave plate, and wherein the sheave is selectively coupled to the second sheave plate when in the second orientation, and wherein the load plate assembly is configured to sense a second horizontal load different than the first horizontal load acting on the second sheave plate.

14. A lift assembly as claimed in claim 13 , wherein the first sheave plate is movable relative to the second sheave plate.

15. A lift assembly as claimed in claim 14 , wherein the first sheave plate is positioned below the second sheave plate in a direction parallel to the fleet axis.

16. A lift assembly as claimed in claim 13 , wherein the sheave is a first sheave of a plurality of sheaves, and wherein the plurality of sheaves is selectively coupled to each of the first sheave plate and the second sheave plate.

17. A lift assembly as claimed in claim 11 , wherein the rotational axis of the sheave is positioned on the first side of the fleet axis in a direction that has a component along a longitudinal axis of the drum when the sheave is in the first orientation, and wherein the rotational axis of the sheave is positioned on the second side of the fleet axis in the direction along the longitudinal axis when the sheave is in the second orientation.

18. A lift assembly as claimed in claim 11 , wherein the sheave is pivotably coupled to the portion of the frame about a pivot axis.

19. The lift assembly of claim 1 , wherein the sheave is rotated 180 degrees about the fleet axis to move the sheave from the first orientation to the second orientation.

20. The lift assembly of claim 1 , wherein the fleet axis does not change when the sheave is coupled to the base in the first and the second orientations.

Assignees

• Electronic Theatre Controls Inc

Inventors

• Hoffend Iii Donald A

Classifications

• B66D1/39 Primary

  by means of axially-movable drums or barrels {(pivotably mounted drums or barrel B66D1/365)} · CPC title

• B66D1/30

  Rope, cable, or chain drums or barrels · CPC title

• A63J1/02

  Scenery; Curtains; Other decorations; Means for moving same {(fireproof curtains A62C2/10)} · CPC title

• B66D1/28

  Other constructional details · CPC title