Beam bender

• US 3,952,572 A
• Filed: 01/23/1974
• Issued: 04/27/1976
• Est. Priority Date: 01/23/1974
• Status: Expired due to Term

• Current Assignee: Case Western Reserve University
• Original Assignee: Case Western Reserve University
• Inventors: Kicher, Thomas P., Savage, Michael, Kosc, Wieslaw, Mergler, Harry W., Wright, Daniel K.
• Primary Examiner(s): Lanham, C. W.
• Assistant Examiner(s): Combs, E. M.
• Application Number:
  US05/435,713
• Time in Patent Office: 825 Days
• Field of Search: 72/295-298, 72/305, 72/308-310, 72/316, 72/318, 72/319, 72/369, 72/387, 72/388, 72/457, 72/458
• US Class Current: 72/298
• CPC Class Codes: B21D 7/02 over a stationary forming member; by use of a swinging forming member or abutment
• CPC Class Codes: B21D 7/03 Apparatus with means to keep the profile in shape

Abstract

A method and apparatus for bending beams by which a beam is subjected to pure moment bending in a critically oriented plane to avoid twist and to maintain single plane bending in a beam of arbitrary cross section. As disclosed, a pair of bending heads laterally engage a beam at longitudinally spaced points. Force actuator means connected directly between the heads is energized to rotate one of the heads relative to the other to produce a bending moment in a work area in the beam between the heads. The actuator means is arranged to produce a force couple on the heads which avoids transverse loading of the beam and resultant twist and which is adapted to selectively orient the plane of the applied couple relative to the desired bending plane to maintain single plane bending in beams of nonsymmetric cross section.

Claims

1. A method of bending a beam comprising the steps of providing a beam having a nonsymmetrical cross section with respect to a first axial plane, laterally engaging the beam at two spaced points with surfaces provided on a pair of longitudinally spaced bending heads, applying a force couple on one of the heads, with sufficient magnitude to cause rotation of the one head relative to the other, in a longitudinal plane oriented from said first axial plane and a second axial plane perpendicular to said first axial plane and having an orientation determined by the cross section of the beam whereby a permanent deflection of the beam is produced solely in said first axial plane.

2. A method as set forth in claim 1, wherein said couple is applied without transversely loading the beam in a work area between said zones.

3. A method as set forth in claim 2, wherein said couple is applied without axially loading the beam in said work area.

4. A method of bending a beam comprising the steps of providing a beam having a nonsymmetrical cross section with respect to a first axial plane, transversely engaging the beam with surfaces provided on a pair of longitudinally spaced bending heads, supporting the heads and beam in a manner to permit rotation of one of said bending heads relative to the other, in a longitudinal plane oriented from said first axial plane and a second axial plane perpendicular to said first axial plane and having an orientation determined by the beam cross section, without significantly transversely loading said beam in a work area between said heads when said heads are rotated relative to one another through a substantial angle, and rotating said one head relative to the other to cause said beam to be permanently bent solely in said first axial plane.

5. A method as set forth in claim 4, wherein said heads and beam are supported in a manner to permit rotation of said one bending head without axially loading said beam in said work area.

6. A method as set forth in claim 5, wherein said one head is rotated by applying a force couple on it.

7. A method as set forth in claim 6, wherein said force couple is developed by force actuator means connected directly between said heads.

8. A method of permanently bending a beam in a desired plane, the cross section of the beam being nonsymmetrical with respect to said desired plane, comprising the steps of laterally engaging surfaces of the beam at longitudinally spaced points along the beam with gripping surfaces of a pair of spaced bending heads, providing on each of the bending heads a first pair of lateral extensions on opposite sides of the beam in a first plane and an associated first pair of linear force actuators connected between said extensions and substantially parallel to the longitudinal axis of the beam, providing on each of the bending heads a second pair of lateral extensions on opposite sides of the beam in a second plane perpendicular to said first plane and an associated second pair of linear force actuators connected between said extensions and substantially parallel to the longitudinal axis of the beam, and simultaneously applying opposite forces in each pair of force actuators to rotate said bending heads in said first and second planes with sufficient amplitude to permanently deform the beam in the desired plane.

9. A method as set forth in claim 8, wherein the force in each pair of said actuators is equalized hydraulically.

10. A method as set forth in claim 8, wherein said beam is bent at successive areas along its length and the beam is advanced between such areas by a stroke developed by one pair of said linear force actuators.

11. A method as set forth in claim 8, wherein a longitudinally extending portion of the beam in a work area between said heads is supported against localized buckling by restraining surface means in abutting engagement with said beam portion.

12. A method of bending a beam in a desired axial plane with which the cross section of the beam is nonsymmetrical, comprising the steps of providing a beam having a nonsymmetrical cross section, laterally gripping the beam with two longitudinally spaced heads, rotating one of the heads relative to the other by applying a bending moment to the one head in a longitudinal plane oriented out of the desired axial plane of bending and a second axial plane perpendicular to said desired axial plane in a manner such that the beam is plastically deformed in a work area between said heads solely in the desired axial plane of bending.

13. A method as set forth in claim 12, wherein said bending moment is applied as the resultant of two moments applied separately to the said one head in perpendicular planes.

14. A method as set forth in claim 13, wherein the angle between the resultant moment plane and the desired bending plane is adjusted by varying the relative magnitudes of said perpendicular separately applied moments.

15. A method as set forth in claim 14, wherein said separately applied moments are developed as force couples.

16. A method of bending a beam in a desired axial plane with which the cross section of the beam is nonsymmetrical, which comprises the steps of providing a beam having a nonsymmetrical cross section, simultaneously applying, through surfaces spaced along the axis of the beam, a pair of bending moments in first and second longitudinal planes perpendicular to each other to produce a resultant bending moment on the beam in a work area between said spaced surfaces in a third longitudinal plane oriented out of the axial plane of desired bending.