EP1243352B1 - Plate pulling head - Google Patents

Abstract

Clamping head of a plate stretcher comprises lamellae (3, 4) divided horizontally to the stretching plane (2) and surrounding the clamping throat (5) of the head with their complementary partial halves above and below the stretching plane. Preferred Features: A steel box (16) is arranged between the lamellae. The lamellae and the clamping throat are connected together using traverses (10, 11) through a pre-tensioned system.

Description

The invention relates to a clamping head of a plate stretcher for stretching and straightening rolled or pressed flat stretched material, in particular sheets and plates, which consists of a variety over the working width of the clamping head, perpendicular to the plane of the stretched material juxtaposed slats on their the work area facing side are formed with a over the entire width of the clamping head extending clamping jaw.

In the known clamping heads, the clamping jaw is composed of vertically arranged to the plane of the stretched slats, which are provided with C-shaped openings and therein for detecting the sheet or the plates necessary clamping devices. From DE-PS 32 05 701 it is known that the reaction forces resulting, acting in the plane of the material to be stretched bending moment, which bends the entire clamping head like a beam mounted on two columns, on the side facing away from the working area of the slats extending over the entire width of the clamping head extending, the slats interconnecting straps or traverses is intercepted.

Far more critical is, in view of further increasing the performance of the plate stretchers, the control of the stress occurring in the mouth of the slats. This stress is caused by the spreading forces arising during the stretching process, which are reaction forces to the tensile forces acting on the clamping jaws. For this purpose, it is known to reduce the stress in the clamping jaw of the slats characterized in that arranged in the center of the clamping head Slats are reinforced in cross-section, ie they are thicker and higher compared to the arranged at the two ends of the clamping head slats. However, this embodiment has the disadvantage that the clamping head is much larger and heavier and the same extent the entire structure including the hydraulics must be reinforced.

Furthermore, from DE-PS 36 33 480 known to reduce the stress caused by the spreading forces in the mouth of the fins, even at full utilization of the performance of the plate stretcher in the case of narrow Reckgut. For this purpose, all lamellae are frictionally connected to each other at their transversely extending in the region of the effect of spreading the outer narrow sides via one above and below the level of the horizontal plane provided.

This makes it possible, with the same applied stretching force narrower, but thicker sheets to stretch or direct and thus to increase the performance of the plate stretcher; However, the structural dimensions and the high weight of the plate tensioner remain unchanged.

The above-described, various embodiments of a plate stretcher has the great disadvantage that due to the high spreading and reaction forces occurring both in the mouth and in the slats themselves, the plate stretcher heads must be made in lamellar construction of a heavy forging material. In particular, when the plate stretcher head must endure extremely high forces during stretching - this is the case, for example, in high-strength aluminum plates - the extensor heads are difficult to transport due to the very high unit weights and the large necessary dimension at the now required high loads.

The invention has for its object to provide a plate tensioner head of the type mentioned, which can muster high stretching forces and yet easy to transport.

This object is achieved in that the lamellae are divided in the plane of the stretched material and embrace the clamping jaw of the clamping head with their complementary part halves above and below the stretching plane in situ form-fitting manner. Although the clamping head according to the invention thus consists of several components, namely the clamping jaw having a C-shaped opening and the upper and lower plate parts enclosing it. However, this achieved sandwich construction allows easy to transport or handle and thus easy to install components. In addition, the internal clamping jaw with its clamping devices made of a high-strength material, such as forging material, and in contrast the slats of a force-absorbing material, preferably sheet metal can be produced. The use of these different materials on the one hand ensures that the clamping jaw can withstand the stresses occurring during a stretching process, in particular in the critical mouth radius. On the other hand deformations in the area of the mouth opening are reduced by the laminations, which arise in a stretching operation due to the spreading forces.

According to a preferred embodiment of the invention, it is proposed that the split slats and the clamping jaw are connected to each other by means of transversely arranged to the plane of traverse trusses by a prestressed system consisting of a tie rod and a pressure piece. The trusses overlap here all slats above and below the stretched, with the tie rods and plungers are each located at the transverse to the spreading force narrow sides of the outer slats. The individual laminations and the clamping jaw are thus braced to a bending and transversely rigid box, whereby a gaping of the individual components is effectively prevented. The thus created On the one hand, the principle of a modular system enables the slab-stretching head to be broken down into individual transportable components and put together on site. On the other hand, due to the material adjustments, optimum absorption of the stresses occurring in the individual components during the stretching process, even at high forces, is ensured.

A further embodiment of the invention provides that a steel box is arranged between the divided slats. This steel box extends from the clamping jaw to the ends of the slats remote from the working area, running parallel to the horizontal plane of division of the slats. The steel box is used to absorb compressive stresses that occur during assembly of the individual components by the prestressed tie rod / pressure piece system and thereby act in the vertical direction on the stretching plane.

According to one embodiment of the invention, it is proposed that the split slats and the clamping jaw are connected to each other via one above and below the level of the level in the working area of the clamping jaw arranged crossbars. The crossbars lie in each case on the upper and lower part blades and are clamped together via a prestressed system consisting of tie rods and compression sleeves. As a result, learn the Teillamellen and the forged clamping jaw additional support in the front head area, ie directly on the scene, where act in a stretching operation, the largest spreading forces. Furthermore, these front crossbars help reduce the size of the laminations in the area of the clamping jaw on the one hand and thus save material weight and on the other hand to absorb the Aufspreizkräfte in a stretching process and distribute it to the entire system.

Fig. 1

einen Spannkopf in der Seitenansicht und teilgeschnitten dargestellt;

Fig. 2

den Spannkopf nach Fig. 1 von vorne gesehen;

Fig. 3

eine Variante eines Spannkopfes, in der Seitenansicht und teilgeschnitten dargestellt; und

Fig. 4

den Spannkopf nach Fig. 3 von vorne gesehen.

Further features and advantages of the invention will become apparent from the claims and the following description of illustrated in the drawings embodiments of the invention. Show it:

Fig. 1

a clamping head in the side view and partially cut shown;

Fig. 2

seen from the front of the chuck of Figure 1;

Fig. 3

a variant of a clamping head, shown in side view and partially cut; and

Fig. 4

seen from the front of the chuck of FIG. 3.

The clamping head 1 of a plate stretcher shown in Fig. 1 consists of vertically nebeneinaner stationary, divided in the plane 2 level slats 3 and 4, the form-fitting engage around a C-shaped clamping jaw 5 over its entire width (see Fig. 2). In the working area facing C-shaped opening of the clamping jaw 5 necessary for clamping the stretchable 6 clamping devices 7, 8 are arranged. Above and below the slats 3, 4 is behind a step-like - the rigidity of the slats 3, 4 improving - 9 each transverse to the stretching plane 2 extending traverse 10, 11 are arranged. The two trusses 10, 11 are clamped on each of the narrow sides 12, 13 of the slats 3, 4 facing tie rods 14 and between the trusses 10, 11 enclosed pressure pieces 15 with each other. Along with this, the individual lamellae 3, 4 or the lamellae-part halves and the chucking jaw 5 bounded by them are frictionally connected with each other.

Between the split slats 3, 4 is parallel to the dividing plane, a steel box 16 is arranged, which in the assembly of the individual slats 3, 4 and the Spannmauls 5 by means of the trusses 10, 11 and tie rods 14 and plungers 15 occurring compressive stress absorbs.

Such a chuck 1 can be disassembled into individual, easily transportable components and put together on a construction site easy to a compact, high forces receiving unit, where he due to the different materials chosen - the jaw 5 can be made of wrought iron and the blades 3, 4 can Sheet metal - its strength and stiffness even with the application of very high stretching forces preserved.

A variant of the clamping head 1 is shown in FIGS. 3 and 4. In this embodiment, in each case additionally stiffening transverse bars 20, 21 are arranged in the front head area 17 above the slats 18 and below the slats 19. These are braced together by tie rods 22 and compression sleeves 23 and thus provide additional support of the slats 18, 19 and the inner clamping jaw 5. On the one hand, this can reduce the size of the fins 18, 19 and on the other hand, the Aufspreizkräfte in the front head area 17 even better added.

Claims (4)

1. . A clamping head of a plate stretcher for stretching and straightening rolled or pressed flat stretched material, in particular sheets and plates, consisting of a plurality of adjacent lamellae distributed over the working width of the clamping head, perpendicular to the plane of the stretched material, which are embodied with a clamping jaw extending over the entire working width of the clamping head on its side facing the working region, characterised in that the lamellae (3, 4, 18, 19) are divided in the stretching plane (2) and positively embrace the clamping jaw (5) of the clamping head (1) in situ with their complementary part halves above and below the stretching plane (2).
2. . The clamping head according to claim 1, characterised in that the divided lamellae (3, 4, 18, 19) and the clamping jaw (5) are interconnected by means of cross members (10, 11) disposed transversely to the stretching plane (2) by a pre-stressed system consisting of a tie rod (14) and a pressure piece (15).
3. . The clamping head according to claim 1 or 2, characterised in that a steel box (16) is arranged between the divided lamellae (3, 4, 18, 19).
4. . The clamping head according to any one of claims 1 to 3, characterised in that the divided lamellae (18, 19) and the clamping jaw (5) are interconnected by means of respectively one cross bolt (20, 21) arranged above and below the stretching plane (2) in the working region of the clamping head (5).

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