Method and device for maintaining a position of a load suspended from a lifting gear

• US 20050224438A1
• Filed: 03/29/2005
• Published: 10/13/2005
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Schulte, Peter, Maurer, Peter
• Granted Patent: US 7,267,240 B2
• Time in Patent Office: Days
• US Class Current: 212/274
• CPC Class Codes: B66C 13/063 electrical

Abstract

In a method for maintaining a position of a load on a lifting gear, a position of a load, which is suspended from a trolley of a lifting gear via at least four cables, is determined and a swinging motion of the load is counteracted by selectively adjusting the length of at least one of the cables.

Claims

1. A method for maintaining a position of a load on a lifting gear, comprising the steps of:

determining a position of a load suspended from a trolley of a lifting gear via at least four cables; and

counteracting a swinging motion of the load by selectively adjusting the length of at least one of the cables.

2. The method of claim 1, wherein the counteracting step includes the step of recognizing a reduction or slack of at least one of the cables as a result of the swinging motion and shortening the at least one cable to make it taut.

3. The method of claim 2, wherein two of the cables are shortened in length.

4. The method of claim 1, wherein the counteracting step includes the step of lengthening at least two of the cables.

5. The method of claim 4, wherein three of the cables are lengthened.

6. The method of claim 1, wherein the counteracting step includes the step of lengthening or shortening two diagonally oppositely disposed cables.

7. The method of claim 1, wherein the counteracting step includes the step of selectively paying out or taking in the cables to maintain a horizontal position of the load during lifting, lowering or swinging motions.

8. The method of claim 1, wherein the load is defined by a skew angle between an x-axis and a centerline through the load, when out of plumb, said skew angle being influenced by changing the length of at least one of the cables.

9. A device for maintaining a position of a load on a lifting gear, comprising:

a trolley; and

a hoisting mechanism including at least four lifting units, each lifting unit having a cable drum which receives a cable for connection to a load-carrying member and/or load, and a separate drive unit operatively connected to the cable drum for adjusting a length of the cable.

10. The device of claim 9, and further comprising a detection system for recognizing and controlling a position of the load.

11. The device of claim 9, wherein the cables extend between the load-carrying member and the lifting units at a slant in relation to a lifting direction of the load.

12. The device of claim 10, wherein the slant of the cable between the load-carrying member and the lifting units is greater than 90°

.

13. The device of claim 10, wherein the detection system and the drive units of the lifting units are constructed for automatic operation.

14. The device of claim 9, wherein the drive units are constructed such that each of the drive units can be controlled and regulated individually.

15. The device of claim 9, wherein the drive unit is an electric motor.