METHOD OF AND APPARATUS FOR STRAIGHTENING A DEFORMED FRAME ELEMENT OF A VEHICLE BODY

Abstract: Method of and apparatus for straightening a deformed frame element (24) of a vehicle body (23). The vehicle body (23) is secured to a horizontal straightening bed (1) at four selected anchoring points (18 to 24), preferably on the body sills (22), and at a further anchoring point located at an area (24a) of the frame element (24) where the deformed condition terminates and embodied in an omnidirectional brace (32). The anchoring at the further anchoring point (24a) is effected by means of a bracket mounted on a support member and comprising two clamping jaws (48, 55). The support member (42) is movable to a selected position along the length of a slot in a beam (28) displaceably mounted on the supporting bed (1), and is adapted to be secured in the selected position. The bracing action is effected by anchoring a collar (33) carried by the support member (42) to the beam (28) by means of a pair of chains (34, 35) and to a futher beam (3) of the straightening bed (1) by means of a bracing rod (36).

Description: Method of and apparatus for straightening a deformed frame element of a vehicle body Technical Field This invention relates to a method of straightening a 5 deformed frame element of a vehicle body, comprising anchoring the vehicle body to a substantially horizontal straightening bed at a plurality of selected anchoring points on the vehicle body, applying a straightening force to at least one force-application point on the frame element 10 to be straightened, and applying to at least one further anchoring point on the vehicle body a bracing force opposing the straightening force. The invention also relates to apparatus for straightenin a deformed frame element of a vehicle body anchored to a 15 substantially horizontal straightening bed at a plurality of selected anchoring points on the vehicle body, com¬ prising force-application means for applying a straighte- ' ning force to at least one force application point on the frame element to be straightened, and bracing means for 20 applying a bracing force opposing the straightening force to a further anchoring point on the vehicle body. Background Art When straightening damaged vehicle bodies, parti¬ cularly self-supporting automobile bodies, it is common 25 practice to secure the body to a horizontal straightening bed by means of suitable anchoring elements at a plurality of, e.g. four, anchoring points on the body, usually on the underside of the body. The anchoring points often are ■ chosen on body sills or other reinforced frame portions, 30 usually in accordance with directions by the manufacturer of the vehicle. To securely hold the body on the supporting bed, bracing means, e.g. in the form of chains, are often applied to take up the straightening force and thereby prevent the body from becoming displaced 35 under the action of the force applied to straighten the deformed frame element. Such bracing means are shown e.g. in U.S. Patent No. 3 590 623. It has been found, however, that when a straightening force is applied in a conventional manner at one or more points on a deformed frame element or other reinforced portion requiring a very heavy straightening force, it is not always possible to control the effect of the straightening force sufficiently to ensure that only the damaged or deformed portion, and not undamaged body portions, are bent. Only a very skilled operator is able to avoid such "overpull". The danger of "over¬ pull" primarily is due to the fact that the sheet metal of modern automobile bodies often is very thin so that it is easily deformed where it is joined to body sills and the like. Disclosure of the Invention The object of the invention is to provide a method and apparatus of the kind indicated with which the danger of "overpull" is eliminated or at least greatly reduced. This object is achieved with the method defined in claim 1 and the apparatus defined in claim 6. Brief Description of the Drawings Fig. 1 is a diagrammatic plan view illustrating the anchoring of a vehicle body to a straightening bed in accordance with the invention; Fig. 2 is a side elevation showing a device embodying the invention ? Fig. 3 shows the device of Fig. 2 viewed from line III-III; Fig. 4 is a fragmentary sectional view on line IV-IV of Fig. 3. Fig. 1 shows a horizontal straightening bed resting on a workshop floor, a platform or the like and com- prising a frame 1 constructed from two longitudinal beams 2 and 3 and four cross-beams 4 to .7 rigidly se¬ cured to the longitudinal beams. Two additional cross-beams 8 and 9 are displaceable along the frame 1 on the upper side thereof and adapted to be secured in position with respect to the beams 2 and 3 by means of suitable re¬ taining assemblies 10 to 13, e.g. comprising washers, bolts and nuts. Each beam 8 and 9 carries two slidable anchors 14, 15 and 16, 17, e.g. in the form of conventional clamps, which are adapted to be secured in position on the beams. The anchors 14 to 17 are adapted to be secured to four selected anchoring points 18 to 21 on the body sills 22 of an automobile body indicated by a broken line at 23 and including a deformed frame portion to be straightened. For illustrative reasons, the part of the body that has been deformed is only shown as an elongated frame element 24. The beams of the frame 1 and the longitudinally displaceable cross-beams 8 and 9 preferably are of the type shown in Fig. 1 of U.S. Patent No. 4,023,394, i.e. they are each provided with a continuous central longi¬ tudinal slot. Such slots provide for a convenient connection of the beams 8 and 9 with the frame 1 and for attachment of frame anchors, straightening apparatus and other devices to the beams. A conventional pull straightening device 25, such as a hydraulic jack, is detachably secured to the beam 7 and conventionally connected through a force-transmitting element in the form of a chain 26 with one end 27 of the deformed frame element 24 to be straightened. Since the pull straightening device 25 with the chain 26 is con¬ ventional and well known in the art, a detailed descrip¬ tion thereof is omitted here. A third cross-beam 28 is displaceable along the upper side of the straightening bed 1. Cross-beam 28 is adapted to be secured in selected positions on the beams 2 and 3 by suitable retaining assemblies 29, 30, e.g. formed by washers, bolts and nuts, and is provided with a central longitudinal slot 31 similar to the above- mentioned slots of the other beams. A brace 32 secured in position on cross-beam 28 is clamped to the frame ele¬ ment 24 at an area 24a thereof where the deformed frame element portion ends. Brace 32 is illustrated in greater detail in Figs. 2 to 4; for illustrative purposes Fig. 1 only sTiows a locking collar 33 forming part of the brace 32. Three anchoring members 34 to 36 anchor the locking collar 33 to the beams 3 and 28 and thus indirectly to the frame 1 so that the anchoring point formed by the area 24< OM is omnidirectionally braced. The anchoring members 34 to 36 comprise two chains 34 and 35 and a bracing rod 36. One end of each of the chains 34 and 35 is connected to a stud bolt 37 and 38, 5 respectively, on the locking collar 33, while the other end is connected to a hook 39 and 40, respectively, near the end of cross-beam 28. Since the details of the hooks 39, 40 form no part of the invention, they are not illustrated. Preferably, the hooks are of the con- 10 ventional type having l movable spindle by means of which the chains 34, 35 may be tightened. The bracing rod 36 constituting the third anchoring element is bifurcated with the bifurcated end pivotally connected to the stud bolts 37, 38 and the opposite 15 end secured to the beam 3 through a suitable pivoted connector 41. Preferably, the bracing rod 36 is adjustable in the longitudinal direction thereof, e.g. by means of an axially displaceable spindle (not shown) . With reference to Fig. 1, the automobile body 23 20 is secured to the straightening bed 1 at the four selected anchoring points 18 to 21 by means of the con¬ ventional anchor clamps 14 to 17. In operation, a straightening force is applied at the force-application point 27 on the deformed frame element 24. In order that 25. "overpull" of the nature described initially may be avoided, the body 23 is also secured to the straightening bed at a fifth anchoring point located at a selected area 24a of the frame element 24 which area separates the deformed portion of the frame element from the un- 30 damaged or undeformed portion thereof. The fifth anchoring point is thus located at an area 24a where the deformed condition of the frame element terminates. Because the fifth anchoring point at the area 24a is embodied as a brace by means of the chains 34 and 35 and the bracing 35 rod 36, which form lateral anchors, and is rigidly connected, through a main anchor in a manner to be de¬ scribed below with reference to Fig. 2, with the cross-beam 28, the straightening device 25 may exert a very great pulling force on the frame element 24 without the effect of the force being extended beyond the anchoring point at the area 24a, i.e. without causing the undamaged portion of the frame element 24 to become distorted. The brace 32 is illustrated in greater detail in Figs. 2 to 4. For illustrative purposes the chains 34 and 35 and the bracing rod 36 are omitted. As best shown in Fig. 4, the locking collar 33 en¬ closes a screw-threaded vertical spindle 42 which is rotatable about its longitudinal axis. The spindle 42 extends through the slot 31 in cross-beam 28 and is clamped to the cross-beam by a retaining assembly com¬ prising two nuts 43, 44 and washers 45, 46. A slot 47 is formed at the upper end of the spindle 42, and in the slot a bracket in the form of a clamping jaw 48 is pivotally mounted on a pin 49 extending transversely through the spindle 42. Spindle 42 thus serves as a clamping jaw support which can be selectively secured in position on the beam 28. Clamping jaw 48 is provided with a toothed segment 50, the teeth 51 of which may be engaged with the locking collar 33 at a recess 52. in the upper side of the locking collar to retain the clamping jaw in a selected angular position thereof, see Fig. 4. Tightening of a lock nut 53 on the spindle after the clamping jaw has been rotated to a selected angular position serves to bring the locking collar 33 in engagement with the teeth 51 and to retain it in the engaged position. Clamping jaw 48 is provided with a clamping element 54 having a knurled clamping face adapted to engage a lateral face of a flange 24b of the frame element 24 in the area 24a. The opposite face of the flange 24b is engaged by a further clamping jaw 55 having a clamping element 56 with a knurled clamping face. The clamping jaws 48 and 55 are held together by bolts 57 and 58 in conventional manner. As " shown in Fig. 4 the clamping ' faces of the vice formed by the clamping jaws 48 and 55 are vertical. If the vice has to be applied to a flange or the like that is not vertical, the clamping jaw 55 may be detached and OΓ PI then remounted on top of clamping jaw 48 by inserting the bolts 57, 58 in bores 59, 60 in the upper portion of clamping jaw 48. As shown in Fig. 3, clamping element 54 of clamping jaw 48 is serrated and adapted to engage the lower side of the flange or the like of the deformed frame element 24. The illustrated and described apparatus provides the following six degrees of freedom in the application of clamping jaws 48 and 55 to an anchoring point on the vehicle body: No. 1: Cross-beam 28 is movable by displacing it parallel to itself along the straightening bed 1. No. 2: Spindle (support member) 42 is movable along the slot 31 longitudinally of beam 28. No. 3: Spindle (support member) 42 is movable along its longitudinal axis, i.e. vertically, in the slot 31 of beam 28. No. 4: Spindle (support member) 42 is rotatable along its longitudinal axis. No. 5: Clamping jaws 48 and 55 are jointly pivotable about pivot pin 49. No. 6: Clamping jaw 55 is movable from the position shown in Fig. 3 in which the vice formed by the clamping jaws 48, 55 has its clamping faces in a vertical plane, to a position on top of jaw 48 in which the clamping jaws form a vice having its clamping faces in a plane perpen¬ dicular to the first-mentioned plane.

Claims: Claims 1. Method of straightening a deformed frame element of a vehicle body, comprising anchoring the vehicle body to a substantially hori- zontal straightening bed at a plurality of selected anchoring points on the vehicle body, applying a straightening force to at least one force- application point on the frame element to be straightened, and applying to at.least one further anchoring point on the vehicle body a bracing force opposing the straightening force, characterized by locating the further anchoring point on the frame element (24) to be straightened at an area (24a) thereof which separates the deformed portion of the frame element from an undeformed portion thereof, and omnidirectionally bracing the frame element at the further anchoring point. 2. Method according to claim 1, characterized by bracing the further anchoring point vertically in a main anchoring point (32) and laterally from three different lateral anchoring points (39,40,41). 3. Method according to claim 2, characterized by connecting the main anchoring point (32) rigidly but detachably with the straightening bed (1) . 4. -Method according to claim 2 or 3, characterized by aligning the main anchoring point (32) and two of the lateral anchoring points (39,40) on a common bracing support (28) . 5. Method according to claim 4, characterized by connecting the bracing support (28) rigidly but detachably with the straightening bed (1) . 6. Apparatus for straightening a deformed frame element of a vehicle body anchored to a substantially horizontal straightening bed at a plurality of selected anchoring points on the vehicle body, comprising force- application means for applying a straightening force to at least one force-application point on the frame element to be straightened, and bracing means for applying a bracing force opposing the straightening force to a further anchoring point on the vehicle body, characterized by a beam (28) displaceable parallel to itself along the supporting bed (1) and retainable in a selected position on the straightening bed, said beam (28) having a longi- tudinal slot (31) , a bracket (48) having means for clamping it to the vehicle body (23) at the further anchoring point (24a) , an elongated support member (42) mounting the bracket (48) , the support member extending into the slot of the beam and being displaceable therein both along the slot and longitudinally of the support member, means (43-46) for clamping the support member (42) in a selected position on the beam (28) , and anchoring members (34-36) operable in conjunction with the clamping means (43-46) to brace the support member (42) omnidirectionally. 7. Apparatus according to claim 6, characterized in that two of said anchoring members (34,35) are rigidly but detachably connectable to the straightening bed (1) . 8. Apparatus according to claim 6 or 7, characterized by a joint (49) pivotally connecting the bracket (48) with the support member (42) . 9. Apparatus according to any of claims 6 to 8, characterized in that the support member (48) is rotatable along its longitudinal axis. 10. Apparatus according to any of claims 6 to 9, characterized in that the bracket (48) is pivotable on the support member (42) and provided with a toothed seg¬ ment (50) , in that a locking sleeve (33) is mounted on the support member and slidable therealong to a locking position in engagement with a selected portion of said toothed segment (50) to lock the bracket in a selected angular position, and in that retaining means (53) is provided to retain the locking sleeve (33) in said locking position. 11. Apparatus according to any of claims 6 to 10, characterized in that the bracket comprises two clamping jaws (48,55) forming in a first position a vice having a first pair of generally vertical confronting clamping faces and in that one (55) of the clamping jaws is movable "BURE to a second position on top of the other clamping jaw (48) to form a vice having a second pair of con¬ fronting clamping faces oriented generally perpendicularly to the first pair of clamping faces. OXP

Inventors: ERICSSON TOMMY TORSTEN, WESTFELDT LARS G, WIDEGREN TAGE KRISTER, ERICSSON, TOMMY, TORSTEN, WESTFELDT, LARS, G., WIDEGREN, TAGE, KRISTER
Applicants: NICATOR AB
Application year: 1982
Main classification: B21D1
IPC codes: B21D1