LOAD CELL

• US 20140262557A1
• Filed: 03/15/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: JOHNSON, Thomas H.
• Granted Patent: US 9,709,436 B2
• Time in Patent Office: Days
• US Class Current: 177/211
• CPC Class Codes: G01G 21/08 Bearing mountings or adjusting means therefor
• CPC Class Codes: G01G 23/002 Means for correcting for obliquity of mounting for pendulum-weight apparatus G01G1/16
• CPC Class Codes: G01G 23/005 Means for preventing overload
• CPC Class Codes: G01G 3/14 measuring variations of electrical resistance G01G3/13 takes precedence
• CPC Class Codes: G01G 3/1412 the supports being parallelogram shaped

Abstract

The invention relates to a load cell symmetrical about a central vertical axis and comprising first and second mounting surfaces, each on the same horizontal plane and configured for attachment to a support structure and to a loading fixture respectively.

Claims

1. A load cell symmetrical about a central vertical axis and comprising first and second mounting surfaces, each on the same horizontal plane and configured for attachment to a support structure and to a loading fixture respectively.

2. A load cell according to claim 1 wherein the load cell is longitudinally and transversely symmetrical respectively about a central longitudinal plane and a central transverse plane perpendicular to one another and transecting at the central vertical axis.

3. A load cell according to claim 1 wherein the first and the second mounting surfaces are located at opposing ends of the load cell.

4. A load cell according to claim 1 wherein the mounting surfaces are located at opposing ends of the load cell and are equidistant the central vertical axis.

5. A load cell according to claim 1 wherein the mounting surfaces are located at opposing ends of the load cell and are equidistant the central vertical axis and are symmetrical thereabout.

6. A load cell according to claim 1 wherein the load cell is of rectangular footprint.

7. A load cell according to claim 1 wherein the load cell is oblong.

8. A load cell according to claim 1 wherein the load cell is formed of a block of material.

9. A load cell according to claim 1 wherein the load cell comprises one or more apertures therein.

10. A load cell according to claim 1 wherein the load cell comprises a first loading member and a second loading member coupled together and capable of relative vertical deflection with respect to one another.

11. A load cell according to claim 10 wherein the first and second mounting surfaces are located in the same horizontal plane on the first and second loading members respectively.

12. A load cell according to claim 10 wherein a first flexure element and a second flexure element are each coupled to the first and the second loading member and are arranged to deform in response to the relative deflection between the first and the second loading members.

13. A load cell according to claim 12 wherein the first flexure element and the second flexure element are capable of symmetric deformation as a result of shear forces perpendicular to the mounting surfaces of the load cell in response to the relative vertical deflection between the first and the second loading members.

14. A load cell according to claim 1 wherein the load cell comprises one or more force responsive elements.

15. A load cell according to claim 14 wherein the force responsive element is engagable with a suitable measuring device operable to detect and measure the effect of shear force perpendicular to the mounting surfaces of the load cell resulting from the shear forces and/or differential bending moments attributable to a load applied to the load cell.

16. A load cell according to claim 1 wherein the load cell comprises one or more strain responsive elements.

17. A load cell according to claim 16 wherein the strain responsive element is engagable with a suitable measuring device operable to detect and measure the effect of shear force perpendicular to the mounting surfaces of the load cell resulting from the shear forces and/or differential bending moments attributable to a load applied to the load cell.

18. A load cell according to claim 17 wherein the strain responsive element is a structural member for mounting a displacement transducer.

19. A load cell according to claim 18 wherein the output of the displacement transducer is proportional to the load applied to the load cell.

20. A load cell according to claim 17 wherein the strain responsive element is flexible member for mounting a strain gauge.

21. A load cell according to claim 17 wherein the strain responsive element is engagable with a plurality of strain gauges.

22. A load cell according to claim 21 wherein the strain responsive element is engagable with one or more pairs of strain gauges.

23. A load cell according to claim 21 wherein the strain gauges are affixed to the load cell.

24. A load cell according to claim 23 wherein the strain gauges are affixed to the inner surface of the first and the second flexure element respectively.

25. A load cell according to claim 20 wherein the strain gauge(s) is/are located such that, in use, the load cell is operable to detect a load caused by shear forces or differential bending moments applied to the load cell by detecting the shear force perpendicular to the mounting surfaces.

26. A load cell according to claim 25 wherein the load cell is operable to detect a load mounted on at least one of the mounting surfaces of the load cell.

27. A load cell according to claim 1 wherein the load cell comprises mounting fixtures.

28. A load cell according to claim 27 wherein the load cell comprises at least one mounting fixture in each of the first and the second mounting surfaces.

29. A load cell according to claim 27 wherein the mounting fixtures are symmetrical about the central vertical axis of the load cell.

30. A load cell according to claim 27 wherein a pair of mounting fixtures is located in each of the first and the second mounting surfaces.

31. A load cell according to claim 28 wherein the mounting fixtures are recesses in the material of the mounting surfaces of the load cell.

32. A load cell according to claim 30 wherein the mounting fixtures may be bolt-receiving recesses in the mounting surfaces of the load cell.

33. A load cell according to claim 31 wherein the mounting fixtures are threaded bolt holes in the mounting surfaces of the load cell.

34. A load cell according to claim 1 wherein the load cell is attachable to a load cell attachment bracket by a coupling element.

37. A weigh scale comprising a load cell according to claim 1 coupled to a load cell attachment bracket assembly comprising a pair of load cell attachment brackets each having mounting elements, and further comprising a load bearing plate coupled to the mounting elements of the pair of load cell attachment brackets.

38. A weigh scale according to claim 37 wherein the weigh scale is a bench scale.

35. A load cell assembly comprising a load cell symmetrical about a central vertical axis and comprising first and second mounting surfaces each on the same horizontal plane;

and a plurality of load cell attachment brackets coupled to the load cell at the first and second mounting surfaces, wherein the load cell attachment brackets are configured for attachment to a support structure and to a loading fixture.

36. A load cell assembly according to claim 35 wherein the load cell comprises a load cell.