WO1989011353A1

WO1989011353A1 - Tension apparatus for use e.g. in conjunction with an automobile body straightener

Info

Publication number: WO1989011353A1
Application number: PCT/FI1989/000088
Authority: WO
Inventors: Toivo Mäkelä
Original assignee: Maekelae Toivo
Priority date: 1988-05-19
Filing date: 1989-05-18
Publication date: 1989-11-30
Also published as: FI83171C; FI882365A; AU3695389A; FI83171B; FI882365A0

Abstract

Tension apparatus for use e.g. in conjunction with an automobile body straightener, said tension apparatus consisting of a frame (1), an interlocking gear (2) attached to the first end of the frame, and a vertical arm (3) attached to the second end. The interlocking gear consists of two essentially identical locking plates (4, 5) mounted opposite to each other in a mirror-image configuration relative to the horizontal centre axis of the tension apparatus. Each locking plate comprises two joint frames (6, 7) placed at a distance from each other and so positioned that they partially overlap when the locking plates are placed oppositely. Between the joint frames is a tightening means (8), e.g. an eccentric shaft, which can be rotated so as to turn the locking plates relative to each other.

Description

TENSION APPARATUS FOR USE E.G. IN CONJUNCTION WITH AN AUTOMOBILE BODY STRAIGHTENER

The present invention relates to a tension apparatus for use e.g. in conjunction with an automobile body straight- ener, said tension apparatus consisting of a frame, an interlocking gear attached to one end of the frame, and a vertical arm attached to the other end.

With previously known tension apparatuses used in conjunc¬ tion with an automobile body straightener, the body of a vehicle secured by means of body clamps is straightened by using suitable tools, such as hydraulic cylinders, chains and pulleys, attached to vertical arms. The straightening is performed either by moving the straightening bench it¬ self in vertical and/or horizontal directions or by tilting the vertical arms. In addition, depending on the equipment employed and the actual needs in each straightening job, combinations of the aforementioned movements may be used. US patent nr. 3,108,629 proposes a tension apparatus which uses an interlocking system whereby the frame of the apparatus is directly attached to the edge of the vehicle body by means of screws, and which uses a straightening unit consisting of a combination of a vertical arm, a chain and a hydraulic cylinder. The drawback with this solution is that it does not meet the varying demands imposed by different straightening jobs and that securing the tension apparatus on the vehicle body takes an unduly long time.

Finnish patent nr. 53930 proposes a tension apparatus for the straightening of an automobile body. In this solution, the vertical arm can be turned in the vertical plane during the straightening operation by means of a power cylinder. In addition, the vertical arm is provided with an auxiliary lever actuated by another power cylinder. The tension apparatus comprises a cradle consisting of a pair of beams placed at a certain distance from each other and joined at one end by three transverse beams to enable the apparatus to withstand the bending stress resulting from the straightening operations. The distance between the cradle beams of the tension apparatus is equal to the width of the straightener frame, so that the cradle beams can be inserted into the frame beams and locked in place. This locked condition cannot be changed during the straightening operation. The drawbacks of this apparatus are the problems resulting from the manner in which the tension apparatus is secured on the straightener frame. Since the apparatus can be attached on the frame in one direction only, changing the lateral direction of the required straightening force is a relatively complicated task, involving an expensive construction. For this reason, the apparatus in question is provided with a separate straightening table which can be rotated relative to the tension apparatus.

.Another tension apparatus for use with an automobile body straightener is proposed by Finnish patent application nr. 862265, which is also mentioned as an example representing the state of the art. The drawback of this solution, too, is the complexity, both in the tension apparatus itself and the straightener as a whole, resulting from the construc¬ tion and manner of securement of the tension apparatus. The result is an expensive and complex system.

The object of the present invention is to eliminate the drawbacks referred to above and to achieve a reliable tension apparatus for use in conjunction with an automobile body straightener that is simple in operation and can be quickly secured in any desired location on the frame of the straightener. The tension apparatus of the invention is characterized in that the interlocking gear consists of two essentially identical locking plates mounted opposite to each other in a mirror-image configuration relative to the horizontal centre axis of the tension apparatus, each lock- ing plate comprising at least two joint frames at a dis¬ tance from each other and so positioned that they partially overlap when the locking plates are placed oppositely, and that between the joint frames is a tightening means, e.g. an eccentric shaft, which can be rotated so as to turn the locking plates relative to each other. The invention pro¬ vides the advantage that the apparatus can be quickly and firmly fastened at any location on a straightener frame beam. Similarly, the apparatus can be quickly and easily released and re-fastened. An additional advantage is cheap construction.

A preferred embodiment of the tension apparatus is charac¬ terized in that the front edge of each locking plate is provided with a stopper which is so placed that, when the interlocking gear is being turned into the closed position, the stoppers move towards each other and remain on the interior side of the locking plates and, relative to the eccentric shaft, on the opposite side of the straightener frame beam. The advantage is a firm hold that also allows a thrust motion.

Another preferred embodiment of the invention is character¬ ized in that the vertical arm at the rear end of the frame is so mounted that it can be moved relative to the front end, e.g. using a power cylinder placed inside the frame. The advantage is a compact construction of the tension apparatus as a whole. By virtue of the easy-to-use inter¬ locking system, the tension apparatus can be constructed using a telescopic frame whose motion constitutes the straightening motion.

In the following, the invention is described by the aid of an example with reference to the drawings attached, where:

Fig. 1 presents a lateral view of the tension apparatus without the supporting structures and wheels. Fig. 2 presents the same tension apparatus in top view and partly sectioned. Fig. 3 presents a lateral view of the interlocking gear in the locked position. Fig. 4 presents a lateral view of the same interlocking gear in the open position. Fig. 5 presents a detail of the interlocking gear as sectioned along line V - V in Fig. 3.

In the description of a preferred embodiment of the inven¬ tion, when referring to the drawings, "front end" or "first end" always means the left-hand end of the device or part in question. Similarly, "rear end" or "second end" means the right-hand end in the drawings. The frame of the ten¬ sion apparatus is a tubular member 21 provided with an in¬ terlocking gear 2 at its front end and a vertical arm 3 at the other end. In addition, the first end of the frame is provided with a back plate 26 against which the frame beam 17 of the automobile body straightener rests. The inter¬ locking gear consists of two gripping jaws nearly identical in construction, one of which is placed on the upper side of the frame 1 and the other on the underside. The basic parts of the interlocking gear are an upper and a lower pivot plate 12, which are mounted on the frame 1 by means of a vertical pivot axle 19. The interlocking gear can be rotated in the horizontal plane about the vertical pivot axle 19 and locked in place in different angles relative to the longitudinal axis of the frame 1. Each pivot plate 12 is provided with two lugs 11 , which are placed on the outer side of the plate, one at each side edge of the plate, starting from its front corner. Furthermore, the inter¬ locking gear has an upper locking plate 4 and a lower lock¬ ing plate 5, which are of a planar construction and, as seen in the rear-to-front direction, constitute an exten¬ sion of the corresponding pivot plates 12 though placed at a certain distance from them. Attached to the outer side of the upper locking plate 4 are two joint frames 6, and similarly, another two joint frames 7 are attached to the outer side of the lower locking plate 5. The locking plates 4 and 5 are wider than the pivot plates 12, so that, when installed, the rear parts of the joint frames attached to the outer edges of the locking plates will fit on the outside of the lugs 11. The joint frame 6,7 consists of an essentially horizontal front part and a rear part which is nearly perpendicular to the front part, the juncture of said parts being provided with a hole for a pivot axle 9, 10. The lugs 11 are also provided with corresponding holes. The horizontal part of each joint frame is attached to the outer side of the relevant locking plate 4 or 5. Seen from the side, the vertical part gets narrower towards the end, its front edge being so inclined that it allows the turning motion required for opening the interlocking gear. The end of the vertical part is provided with a notch 25 for the eccentric shaft of the tightening means 8. The ends of the upper and lower joint frames 6 and 7 overlap partially in such manner that they can all be actuated by the same tightening means 8. The overlap is implemented e.g. by providing a thinner part at the end of each vertical joint frame part as illustrated by Fig. 5. Each locking plate 4,5 is provided with a stopper 15,16 of a length corresponding to the width of the locking plate. The distance between the stoppers and the back plate 26, when the interlocking gear is in the locked position, is equal to the width of the frame beam 17 of the automobile body straightener. An essentially horizontal eccentric shaft 8 acting as a tight¬ ening means is located at the centre axis of the tension apparatus. The joints of the eccentric shaft are located in the side plates of the frame 1 somewhat farther away from the front edge of the first end of the tension apparatus than the pivot axles 9 and 10 of the joint plates 6 and 7. The eccentric shaft 8 consists of a middle part which is of a larger diameter and rotatably mounted in the frame 1 , and an eccentric pin of a smaller diameter at each end of the shaft. These mutually coaxial eccentric pins engage the joint plates 6 and 7 by the notches 25. The length of the eccentric pins is such that their ends protrude outside the vertical plane of the joint frames. Attached to one end of the eccentric shaft 8 is a lever arm 13 pointing towards the rear end of the frame, the lever arm being provided with a crank pin 14. The crank pin extends laterally far enough outside the joint plates to enable the arm to be easily turned by hand.

The interlocking gear is released by turning the lever arm 13 anti-clockwise by the crank pin 14 so that the eccentric shaft 8 is also forced to turn anti-clockwise, causing the eccentric pins in the notches of the joint frames to move forwards, thereby forcing the ends of the vertical parts of the joint frames to move forwards. The result is that the joint frames 6 and 7 are rotated clockwise/anticlockwise about their pivot axles 9 and 10, whereby the locking plates 4 and 5, and likewise the stoppers 15 and 16, are moved up and down, respectively, and the frame beam 17 of the automobile body straightener is released from the grip of the interlocking gear. The locking operation is performed in the reverse order by turning the crank pin 14 clockwise, whereby the interlocking gear is closed.

Generally, the tension apparatus is used together with chains to perform a tensioning operation, but its construc¬ tion also allows thrust operations because the stoppers en¬ sure a firm grip and, above all, because the frame 1 is of a telescopic construction and actuated by a power cylinder, e.g. a hydraulic cylinder, placed inside the tension apparatus. Since the forces are internal, the securing arrangements used in this solution are sufficient to allow the application of thrust. The frame 1 consists of an outer tube 21 , one end of which is connected to the interlocking gear, and an inner tube 22 placed inside the outer tube and connected to the vertical arm 3 and the devices used in conjunction with it. The cylinder part of the hydraulic cylinder is attached to a horizontal anchor bolt 20 located in the vertical direction at the level of the midline of the outer tube 21. Similarly, the piston part 23 of the hydraulic cylinder is attached to a horizontal anchor bolt 24 located at the level of the midline of the inner tube 22. The hydraulic cylinder is placed in an essentially horizontal position, and when the piston 23 moves, the inner tube 22 also moves telescopically relative to the outer tube 21. This motion provides the required tension and thrust in the tension apparatus. One end of the chain needed in a tensioning operation is attached to the body¬ work of the vehicle and the other end to the vertical arm 3 at a suitable height. The vertical arm 3 can be tilted by known techniques.

It is obvious to a person skilled. in the art that different embodiments of the invention are not restricted to the example described above, but that they may instead be varied within the scope of the following claims.

Claims

1. Tension apparatus for use e.g. in conjunction with an automobile body straightener, said tension apparatus con¬ sisting of a frame (1), an interlocking gear (2) attached to the first end of the frame, and a vertical arm (3) attached to the second end, c h a r a c t e r i z e d in that the interlocking gear consists of two essentially identical locking plates (4, 5) mounted opposite to each other in a mirror-image configuration relative to the hori¬ zontal centre axis of the tension apparatus, each locking plate comprising at least two joint frames (6, 7) at a dis¬ tance from each other and so positioned that they partially overlap when the locking plates are placed oppositely, and that between the joint frames is a tightening means (8), e.g. an eccentric shaft, which can be rotated so as to turn the locking plates relative to each other.

2. Tension apparatus according to claim 1, c h a r a c ¬ t e r i z e d in that the front edge of each locking plate is provided with a stopper (15, 16) which is so placed that, when the interlocking gear is turned into the closed position, the stoppers move towards each other and remain on the interior side of the locking plates and, relative to the eccentric shaft (8), on the opposite side of the straightener frame beam (17).

3. Tension apparatus according to claim 1 or 2, c h a r ¬ a c t e r i z e d in that the vertical arm (3) at the second end of the frame is so mounted that it can be moved relative to the first end, e.g. using a power cylinder (18) placed inside the frame (1).