GB2170743A - Device for fixing an elastically deformable component part - Google Patents

Abstract

A device, eg. for feeding a plate 6 with a hard foam backing 8 beneath a hammer 2, comprises a supporting body 4, supporting the component part 6, and at least one roller unit 16 which contains a pair of feeding pressure rollers 22, 24. The roller unit 16 is arranged so as to be swingably-movable on a roller carrier 18 and is provided with an associated swivel-angle adjusting mechanism 38 (36, Figure 2) which aligns the roller gap W in any position of the roller carrier automatically at the local surface inclination of the component part 6, whereby deformation and shaping errors of the component part 6 under the effect of the roller pressure forces are avoided. The angle of a beam 20 carrying the roller 24 is adjustable by gearing (40, 42) linked 38 to a support 2 for the anvil 4. The roller 24 is applied by an hydraulic cylinder 26. <IMAGE>

Description

SPECIFICATION Device for fixing an elastically deformable component part This invention relates to a device for fixing an elastically deformable curved plate-shaped component part, said device comprising a supporting body, which supports the component part, and at least one roller carrier adjustable in height and laterally displaceable with respect to the supporting body in accordance with the curvature of the component part and provided with a roller unit having pressure rollers which are axially-parallel to the supporting body and which receive the component part in a roller gap between them and are pressed against the component part.

Known devices of this kind, as are needed for instance upon the non-cutting cold shaping of aircraft fuselage shells and skins in accordance with the percussion hammer method in accordance with DE-OS 31 11 148.3, comprise not only the supporting body, which is arranged in the impact plane of the hammer and which acts as an anvil, but also generally several roller units which are arranged on both sides of the supporting body in order to keep the component part in a biassed state during shaping. The roller units are mobile or movable in a direction and manner which corresponds with the curvature of the component part and consist in each case of a pair of pressure rollers which receive the component part between them and are pressed against the component part and which revolve upon the advance through the gap of the component part.In this respect, there arises in the roller gap a bending movement exerted on the component part and the degree of which is dictated by the roller pressure forces acting offset to one another and depending on the relative position of the roller unit with respect to the supporting body. The effect of the bending movement on the component part leads to a defective fixing of the component part and to deviations from the preselected curvature course fixed by appropriate positioning of the roller units, which, in connection with the above-described impact hammer method, results in incorrect biasses in the component part and permanent shaping errors.

The task of the invention is to provide a device of the kind as aforesaid in such a way that, unaffected by the roller pressure forces acting in the roller gap, an exact fixing of the component part in a variably selectable curvature geometry is guaranteed.

This task is achieved by the present invention in that it provides a device for fixing an elastically deformable curved plate-shaped component part, said device comprising a supporting body, which supports the component part, and at least one roller carrier adjustable in height and laterally dis placeable with respect to the supporting body in accordance with the curvature of the component part and provided with a roller unit having pressure rollers which are axially-parallel to the sup porting body and which receive the component part in a roller gap between them and are pressed against the component part, characterised in that the roller unit is arranged so as to be swingablymovable on the roller carrier and is provided with an associated angle-of-swing adjusting mechanism which is effective between the roller carrier and the roller unit and which adjusts the swivel position of the roller unit as a function of the height position and the lateral distance of the roller carrier with regard to the supporting body in such a way that the roller pressure force of the pressure rollers extends in the direction of the surface normal of the component part in the roller gap.

In accordance with the invention, as a result of the special tiltingly-movable arrangement and compulsory swivel-position control of the roller unit, an automatic alignment of the roller gap at the local surface inclination of the component part is achieved and it is ensured that the roller contact pressure forces exerted by the pressure roller on both sides on the component part in the roller gap have no influence on the curvature course of the component part. As a result, the component part can be clamped with a high mutual or two-sided roller contact pressure between the pressure rollers and can be fixed free from deformation and shaping errors securely, reliably and exactly in a spatially-defined curved state.The device in accordance with the present invention is therefore suitable in an outstanding way for use in a percussion hammer machine, where the component part has to be fed with a defined bias and elastic deformation to the processing location present at the supporting body and be carried away from this in a permanently deformed, curved state.

With a view to a particularly simple swivel-position control for component parts which are curved in a circular-arc-shaped manner, the swivel angle of the roller unit is preferably equal to the apex angle of an isosceles triangle, the apex point of which lies in the curvature centre of the component part and the base of which extends from the supporting body of the roller gap.

The pressure rollers of each roller unit consist preferably of a curvature-inner and curvature-outer pressure roller and the one triangle leg of the isosceles triangle lies in a fixed plane extending through the supporting body, whilst the other triangle leg lies in the connection plane defined by the centre axes of the two pressure rollers, whereby a very simple geometrical connection between the respective position of the roller carrier and the associated swivel angle of the roller unit is achieved and it is ensured that the component at the supporting body assumes a constant angle of inclination which is perpendicular to the fixed plane. In other words, for example in the case of the said percussion hammer deformation with a vertical percussion-hammer impact direction a horizontal component part feed to the processing location is obtained.To control the roller contact pressure, and in order to achieve, irrespective of the forces effective in the roller gap, an exact compulsory axial guidance of the pressure rollers on the roller unit in the direction of the axis connec tion plane, preferably one pressure roller is mounted with its centre axis stationarily on the roller unit and the other is mounted so as to be movable in the direction of the connection plane and can be acted upon with pressure in a controlled manner.

By virtue of the controllable roller squeezing pressure which acts on both sides on the component part, at the roller unit, in addition to the exact fixing of the component part, also in a simple manner a component part advance can be achieved in that at least one, but preferably all the pressure rollers are driven in the direction of rotation.

With a view to a mounting of the roller unit on the roller carrier, which is particularly favourable for the swivel-position geometry, the roller unit is preferably mounted on the roller carrier so as to be swingably-movable about the centre axis of the pressure roller which is arranged on the same side of the component part as the supporting body.

In a particularly preferred manner, the adjusting mechanism comprises a control lever designed as a telescopic guide rod, connected on the one hand to a pivot on the roller carrier and on the other hand to a fixed pivot, as well as a drive-locking connection which is effective between the control lever and the roller unit and which adjusts the swivel position of the roller unit as a function of the angle of rotation of the control lever, whereby in an extremely simple mechanical manner a compulsory adjustment of the swivel angle, associated with the respective position of the roller carrier, of the roller unit is brought about.If, in this case, the pivots of the control lever are so placed that they form, together with the swivel axis of the roller unit and the supporting body, a parallelogram, there emerges a further quite considerable structural simplification of the adjusting mechanism, in such a manner that a drive-locking connection between control lever and roller unit merely an angle-of-rotation doubling gearing is needed.

The invention will be described further, by way of example, with reference to the accompanying drawings in which: Figure 1 is a part-sectional elevation of a preferred embodiment of the fixing device of the present invention shown being used in conjunction with a percussion hammer for deforming a component part held in the device; and Figure 2 is an enlarged detail view of a swivelangle adjusting mechanism of the preferred device shown in Figure 1.

Referring now to the drawings, the preferred device shown therein comprises a roller-shaped, barrel-shaped or cylindrical supporting body 4 which is mounted rotatably on a stationary post, pillar or upright 2 and on which body 4 is supported a component part 6, by means of its underside (layer 8), which consists of a sheet-metal plate 10 which is lined with a yielding material, for example a hard-form layer 8, to compensate for differences in wall thickness. The component part 6 is permanently deformed by a percussion hammer 12 which goes up and down and which brings about a stretching of the outer edge zones of the sheetmetal plate 10, in which respect the impact direction of the percussion hammer 12 lies in a fixed vertical plane A-A which extends centrally through the supporting body 4 as shown in Figure 1.

The component part 6 has to run or move through the processing location with or under a preset bias, initial tension or stress, namely under elastic tensile elongation of the outer edge zones of the sheet-metal plate, in the advance direction R in such a way that the tangential plane of the component part at the processing location extends perpendicularly to the plane A-A, in other words horizontally, i.e. the component part 6 has to be moved with a preset curvature, which is weaker at the run-in side of the processing location but which is more severe at the run-off side taking into account the permanent deformation, in the advance direction R past the percussion hammer 12, in which respect the respective curvature centre points K and K' have to lie in the fixed plane A-A.

For this purpose, provided on each side of the supporting body 4 is a respective roller arrangement 14 each of which have an identical type of construction, which in Figure 1 is shown only for the run-in-side roller arrangement 14. Each roller arrangement 14 comprises a roller unit 16 with a swivel beam 20 which is mounted on a roller carrier 18 so as to be rotatable about a swivel axis S, and two pressure rollers 22, 24 which receive between them in a roller gap W the component part 6 and are pressed against the component part 6.

The inner pressure roller 22 is mounted so as to be rotatable about the swivel axis S of the swivel beam 20 and the outer pressure roller 24 is supported on the swivel beam 20 by a hydraulic cylinder 26 for regulating the roller bearing, or contact pressure and is positively guided in a linearly movable manner with its axis of rotation in a connection plane V-V which is positionally-fixed with respect to the swivel beam 20 and which extends through the two pressure-roller axes. To achieve an advance of the component part 6, a drive 28 for the two pressure rollers 22 and 24 is arranged on the swivel beam 20.

In order to position the roller unit 16 both laterally and vertically (i.e. in the X and Y directions shown in Figure 1) in accordance with the preset curvature of the component part 6 and with respect to the supporting body 4 the roller carrier 18 is guided on a positioning carriage 32 so as to be vertically displaceable and adjustable by spindle stroke or lifting elements 30 (adjustment of the Ycoordinate), which carriage 32 is for its part mounted on the machine bed so as to be horizontally movable and adjustable by way of spindle elements 34 (adjustment of the X-coordinate).

In addition to this X- and Y-positioning, the swivel position of the roller unit 16 in variably adjustable in such a way that the roller pressure forces, exerted by the pressure rollers 22, 24 on the component part 6, in each position of the roller carrier 18 act in the direction of that surface which is normal with respect to the component part 6 in the roller gap W, i.e. the axis-of-rotation connec tion plane V-V of the two pressure rollers 22, 24 extends through the respective curvature centre K of the component part 6, whereby an exact fixing of the component part 6 is brought about and deviations from the preselected curvature course are prevented.It is easily evident from Figure 1 that in the depicted X-, Y-position of the roller arrangement 14, but in a different one from the depicted swivel position of the connection plane V-V under the effect of the roller pressure forces exerted in the roller gap on the upper and lower side of the component part, bending moments would be generated in the component part 6 which would result in deformation or shaping errors of the component part 6 and consequently deviations from the curvature course preselected by the X-, Y-position of the roller unit 16.

For the automatic swivel-position adjustment, variable as a function of the X- and Y-position, of the roller unit 16 there is provided a swivel-angle adjusting mechanism 36 which is shown in detail in Figure 2 and the mode of construction and operation will be explained in more detail hereinafter.

As has already been mentioned, the connection plane V-V must in any position of the roller unit 16, or respectively of the roller carrier 18, extend through the respective curvature centre K of the component part 6, i.e. the swivel angle of the roller unit 16 is to be so selected that it is equal to the apex angle ss of an isosceles triangle (Figure 1), the apex of which lies in the curvature centre K and the base of which extends from the axis S of the roller unit 16 to a stationary reference point B which lies on the plane A-A and which is formed by the centre point of the supporting body 4 shown in Figure 1.In the case of a supporting body which is differently shaped, for example the one shown in broken lines in Figure 1, said swivel angle is defined in that its distance from the abutment location of the supporting body 4 against the component part 6 is equal to the radius of the pressure roller 22.

The adjusting mechanism 36 provided for the positive control of the roller unit 16 to the swivel angle ss comprises a control lever 38 which is telescopic and which is hinged at one end to the post 2 by way of a fixed pivot D1 and by its other end to the roller carrier 18 by way of a pivot D2, in which respect the position of the pivot D2, on the roller carrier 18 is so selected that the points DI, D2, B and S form a parallelogram. In other words the length of the control lever 38 between its pivots D, and D2 and its angle of inclination a in any position of the roller carrier 18 is equal to the length and the angle of inclination of the said triangular stretch SB.

The control lever 38 is connected drive-lockingly to the roller unit 16 by transmission gearing 36 (Figure 2), e.g. Step-up gearing, which consists of a toothed-wheel segment 40, which is fastened to the control lever 38 and which is mounted for rotation jointly with the control lever 38 about the axis D2 on the roller carrier 18, an intermediate wheel 42 and a further toothed-wheel segment 44 which is fastened coaxially to the swivel axis S of the swivel beam 20 of the roller unit 16. The transmission gearing 36 is so designed that it brings about a doubling of the swivel angle. In other words, the swivel angle ss in each X-, Y-position of the roller carrier 18 is twice as great as the respective angle of inclination a of the control lever 38, whereby there is ensured an automatic alignment, forcibly linked with the X- and Y- coordinates of the roller unit 16, of the connection plane V and consequently of the roller gap W perpendicularly to the local surface inclination of the component part 6.

Claims (9)

1. A device for fixing an elastically deformable curved plate-shaped component part, said device comprising a supporting body, which supports the component part, and at least one roller carrier adjustable in height and laterally displaceable with respect to the supporting body in accordance with the curvature of the component part and provided with a roller unit having pressure rollers which are axially-parallel to the supporting body and which receive the component part in a roller gap between them and are pressed against the component part, characterised in that the roller unit is arranged so as to be swingably-movable on the roller carrier and is provided with an associated angle-of-swing adjusting mechanism which is effective between the roller carrier and the roller unit and which adjusts the swivel position of the roller unit as a function of the height position and the lateral distance of the roller carrier with regard to the supporting body in such a way that the roller pressure force of the pressure rollers extends in the direction of the surface normal of the component part in the roller gap.

2. A device as claimed in claim 1, characterised in that the angle of swing of the roller unit is equal to the apex angle of an isosceles triangle, the apex point of which lies in the curvature centre of the component part and the base of which extends from the supporting body to the roller gap.

3. A device as claimed in claim 2, in which the pressure rollers consist of a pair of rollers, characterised in that the one triangle leg lies in a fixed plane extending through the supporting body and the other triangle leg lies in the connection plane extending through the centre axes of the two pressure rollers.

4. A device as claimed in claim 3, characterised in that one pressure roller is mounted with its centre axis stationarily on the roller unit and the other roller is mounted movably in the direction of the connection plane and can be acted upon with pressure.

5. A device as claimed in any one of the preceding claims, characterised in that at least one pressure roller is driven, for the purpose of achieving an advance of the component part, in the direction of rotation.

6. A device as claimed in any one of the preceding claims, characterised in that the roller unit is mounted on the roller carrier so as to be swingably-movable about the centre axis of the pressure roller which is arranged on the same side of the component part as the supporting body.

7. A device as claimed in any one of the preceding claims, characterised in that the adjusting mechanism comprises a control lever, designed as a longitudinally-displaceable telescopic guide rod and hinged on the one hand to a pivot on the roller carrier and on the other hand to a fixed pivot, as well as a drive-locking connection which is effective between the control lever and the roller unit and which adjusts the swivel position of the roller unit as a function of the angle of rotation of the control lever.

8. A device as claimed in claim 7, characterised in that the two pivots of the control lever as well as the swivel axis of the roller unit and the supporting body lie on the corners of a parallelogram and, provided as a drive-locking connection between the control lever and the roller unit, is a transmission or step-up gearing which converts a change in the angle of rotation of the control lever into a swivel angle movement of the roller unit, which movement is twice as large.

9. A device for fixing an elastically deformable curved plate-shaped component part substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.