DE2341886A1 - METAL SPREADING METHOD AND DEVICE - Google Patents

Description

16 Aug 1973

Method and device for spreading metal

The invention relates to a method and a device for Spreading metal, the slits between side by side-ii found ribs, so that a truss-like component or β i spread lattice is formed.

It has already been suggested to produce an expanded metal in which a metal strip of constant thickness is cut so that it has several rows of slots, the slots of one row being arranged opposite the slots in the next adjacent row . The metal edges are then pulled apart to pull the metal between nebeneir.-other opposite slots apart, to tilt the metal ribs to the plane of the metal prior to bending and to form a grid-like panel. Such a panel has certain limited uses, but is not suitable for use as a load bearing component, primarily because of the high stress concentrations at the ends of the slots and secondly because of the deflection and displacement of the metal between adjacent slots.

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BATH ORIGINAL

This problem has been "recognized" and several suggestions have been made were made to create a component that, for example is suitable as a load-bearing component. For example According to US Pat. No. 1,510,702, a framework-like metal support is used produced by first forming the slots between ribs and then spreading the ribs open, that the metal section gradually diverges in the longitudinal direction end guides is moved. U.S. Patent 1,510,702 also shows that a subsequent rolling cycle can be carried out if necessary. U.S. Patents 1,510,697, 1,472,770, 1,472,771 and 1 4-72 772 different methods for spreading a slotted metal part are specified, in which either rollers or the application of heat is used. In some cases this is due to the distortion of the hips in a plane below one at right angles to the vertical plane of the product to achieve preliminary elongation of the hips.

In US-PS 2 0i0 670 the production of an openwork: Structure for a component described in which a material web has several rows of mutually offset slots, but the conventional stretching guide is also used. Also in US-PS 1,927 44-2 the use of a wedge-shaped Tool described which includes both the grid and the flanges and causes the flanges to separate will.

While the known facilities and procedures for a Are suitable for mass production of a single size of an openwork lattice component, they are not suitable for the general production of different components, and the tooling costs are not affordable when using production aisles small quantities for different component shapes are to be carried out on a single machine.

The invention is therefore based on the object of a spreading machine to create a universal application for

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spread slotted metal parts, so that the machine quickly and easily from one form of expansion to one others can be set. Furthermore, the need for expansion rollers should be avoided, which would otherwise be necessary for the production a satisfactory product were required. After all, the spreading machine should be quick and easy to use a workpiece can be loaded, which then spreads the workpiece and easy removal of the spread workpiece allowed.

The method according to the invention for spreading a workpiece, the two spaced apart, parallel strips, a material web between the tapes and several rows of slots in the web of material, the slots in each row are offset with respect to the slots in at least one adjacent row and these overlap, essentially consists in that tools are mounted in tool holders of a device for spreading metal, that a hand-operated Valve control device is actuated to further inward movement of the movable tool carrier to cause the edges of the workpiece to be attached to the appropriate tools, that the actuation of work cylinder is started to separate the edges and the parts of the web of material separated by the slots are to be deformed, and that after deformation the workpiece by an initial inward movement of the movable Tool holder is released, whereupon the deformed and relaxed workpiece is removed from the tools.

The invention accordingly provides a process is provided in which the workpiece is expanded first, in order to stretch it, and which may then relax before it is removed from the tools · that define its edges.

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The device according to the invention for spreading metal essentially has a frame with longitudinal parts and transverse beams which carry a tool holder that is connected to the frame via pressure fluid adjustment cylinder are coupled, wherein a valve device is provided which can be actuated by stop devices carried on the movable tool mount and arranged so that the cylinders when actuated first move one tool holder away from the other in the transverse direction, whereby one on the tools on the tool holders attached workpiece is stretched, while after the completion of the stretching the cylinder in the reverse Act in the direction so that one tool holder is moved inwards towards the other until another stop device, which is carried by the tool holder, the valve (after an initial inward movement of the tool holder) controls and terminates the actuation of the cylinder, so that the workpiece is relaxed and easy in its tools it is removable. This allows the workpiece to be inserted into the machine quickly and easily and quickly and easily again can be taken from it. The extent of the spreading can preferably be adjusted by means of threaded parts. Can also first, adjustable stop device, which reverses the actuation direction of the cylinders, serves as a device, which limits the spreading of the workpiece.

The device according to the invention can be used for different shapes and spreads of different sizes with relatively simple Tool exchange and easy readjustment can be used.

In particular, a device according to the invention for! spread of metal a frame with a longitudinal part and itself for this purpose, supports extending in the transverse direction, tool supports which are carried by the supports and which extend in the longitudinal direction extend on a plurality of pressure-actuated cylinders

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the frame and means to connect the cylinders to the tool carrier so that actuation of the cylinders causes the tool holder to move over the carrier. Furthermore, a valve device is provided, wherein Pressure medium lines couple the valves with the cylinders so that the operation of the valves causes the actuation of the cylinders , while first and second valve control devices are arranged on the frame and are respectively coupled to the valves are. A first adjustable stop device carried by the moveable tool carrier cooperates with the first valve control means to reverse the actuation of the cylinders at the end of the outward movement of the tool carrier to effect, while a second, adjustable stop device, which is also on the movable tool carrier is carried, cooperates with the second valve control device to terminate the actuation of the cylinders after an initial inward movement of the movable tool holder causes. A hand operated valve control is provided to permit further inward movement of the tool holder to effect.

If a workpiece has several rows of mutually offset slots and is spread apart by deformation, so that the web sections between the edges of the workpiece are spread open, the ends of the middle sections of the lattice that are not directly connected to the edges are not subjected to tension when the edges are separated. Therefore, the ends of the workpiece after stretching are short Lengths that are not the same shape as the intermediate portion of the stretched part. To avoid this irregular end pieces become scrap, it is necessary- ' borrowed, an extension to the middle lattice sections; be practiced. However, it has been shown that a definition

of these sections against inward longitudinal movement (while moving the edges apart in the transverse direction is completely unsatisfactory in most cases

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and greatly restricts the spread of the workpiece.

According to a further embodiment of the invention, the device for spreading metal with corresponding workpiece clamps at each end of the frame, further pressure medium-actuated Cylinders on the frame, their piston rod or with the other workpiece clamps for moving these V / piece clamps are coupled in the longitudinal direction, and provided with further control valves, which via lines with the other fluid-actuated cylinders are connected. This allows the other workpiece clamps to be attached to the middle sections of a workpiece are clamped to stretch the central sections longitudinally after the main stretching jaws have yielded in the transverse direction to relieve the tension in the grid. By doing this, an even Pattern achieved throughout the workpiece.

An embodiment of the invention will now be made with reference to the enclosed Drawings described. Show it:

Pig. 1 is a partial plan view of a device for spreading metal;

Pig. 2 is a section along line 2-2 of S ¹ Xg. 1 in side view;

Pig. Figure 3 is a section taken along line 3-3 of Figure 1 in end elevation;

Figure 4 is a section along line 4-4 of Pig. 1 in End view;

Pig. 5 is a plan view of a workpiece before stretching wherein the edges, the web of material and the rows of mutually offset, overlapping one another Slits are shown dividing the web of material into a series of stretchable sections;

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6 shows a section along the line 6-6 of FIG.

FIG. 7 is a plan view corresponding to FIG. 5, however

shows the workpiece after stretching; ;

Fig. 8 is a section along the line 8-8 of FIG. 7 ^"WO! however, in addition to the workpiece, also the
Tools and tool holders used in stretching are shown;

FIG. 9 is a section along the line 9-9 of FIG. 1;
which shows the end brackets that are used for the secondary
or longitudinal stretching of the workpiece can be used !;

Fig. 10 is a partial plan view showing a lattice-like

Workpiece shows' uei which the webs during the spreading the workpiece is bent more than it is stretched;

FIG. 11 shows a section along the line 11-11 of FIG. 10
on an enlarged scale;

Fig. 12 is an enlarged plan view showing the location of the work

tool after spreading the workpiece, which is in; Fig. 10 is activated;

13 is a partial perspective view of the j

Control devices for the arrangement of tools, J

those in FIGS. 10, 11 and 12 are shown prior to the spreading j of the tool; and

14 shows a schematic representation of the hydraulic and electrical control devices for the device.

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The device 20 for spreading metal essentially has a frame 21 0? ign. 1, 2, 3 and 4), which has a single longitudinal part 22 with an I-shaped cross-section and carrier 23, which extend transversely to the longitudinal part 22.

Tool holders 26 are carried by the carriers 23 by resting on them, and are with the frame 20 through several pressure medium-actuated cylinder 27 connected. It should be noted that in the embodiment described, both tool holders 26 are arranged so that they are movable over the carriers. It is evident, however, that in many cases only one holder has to be movable and that a tool holder can be attached to the frame 20. The cylinders 27 are connected to frame 20 by rotating blocks 28 which will be described in detail later and which are limited relative Allow the cylinder 27 to pivot.

The valve device is in the JFign. 1, 2, 3 or 4 that the show the physical configuration of the device, not shown but schematically in Pig. 14 as the only one. Valve 30 (more than one valve may be used in practice) with the only valve 30 being a solenoid valve and is connected by pressure medium lines 31 to the cylinders 27, so that the actuation of the valve 30 is the actuation of the cylinder 27 causes.

A valve control device is attached to the frame 21. Sine The first valve control device is a limit switch 33> which is attached to a cross member 23 (JFign. 1 and 14) and through an adjustable stop 34 is actuated on a Arm 35 is carried on the tool holder 36. A second valve control device has a second limit switch 37 which is also attached to the cross member 23 and serves to reverse the operating phase of the valve 30. This one will

actuated by a second adjustable stop 38 which : is also worn on the arm 35. On the stop 38 is a Swivel arm 39 is arranged so that the second limit switch 37

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only when the movement is reversed (i.e. "when moving inwards direction) of the tool holder 26 is actuated. The valve 30 is further controlled by a manually operable valve control device in the form of two push-button switches 41 and 42 (Fig. 14 ·) controlled. From Fig. 14 it can be seen that one of these The switch causes the actuation of the cylinder 27 to continue in the inward direction, this movement beforehand was blocked by the limit switch 37. The actuation of the second pressure switch 42 releases the outwardly directed Arbeilshub of the corresponding cylinder 27.

After the workpiece has been spread open, are apparent the ends of some webs that are not directly connected to the ligaments have not themselves been stretched (Fig. 7) To avoid wastage of material, it is desirable to stretch these middle sections separately. To this end, assigns the device end clamps 45 for the workpiece, which under the control of further pressure-medium-actuated cylinders 46, which are referred to as final stretching cylinders. The cylinders 46 are pivotally mounted on brackets 37 which extend outwardly from the frame 20 at the respective ends (Fig. 2). These cylinders are controlled by further control valves (not shown), which are manually operated or electrically can be operated, but are constantly under the control of the operator. In this embodiment there is no automatic deactivation of the actuation of the cylinders 46 is provided, although the automatic control of the cylinders 27 can be doubled for this purpose.

While the main components of the device according to the invention ₍

are described above, the embodiment will be described in greater detail in the following. Each of the cylinders 27 is

pivotably mounted in a rotating block 28 (I ¹ Ig. 1 and 3). In ■

a threaded rod 49 is rotatably mounted on the rotating block 28, '

which carries two pairs of nuts 50, the arrangement being as follows ^:

fen is that the nut 50 on the corresponding rotating block 28,

at the inner or outer end of the working stroke of the ent- ■

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speaking cylinder 27 attacks. As a result, the work is positively "limited, and the adjustable stop 354- is set in such a way that the reversal of the valve JO does not take place" until the working stroke is fixed by the nut ^ O. In certain cases it is desirable that the workpiece be stretched so that the final product has inclined sides rather than parallel sides. In the device described, this can easily be achieved by a simple readjustment of the nuts 50, since both the cylinders 27 and the threaded rods 29 are rotatably mounted and pivotably mounted on corresponding supports 50 on the brackets 26.

The FIGS. 5, 6, 7 and 8 show workpieces before and after the spreading caused by stretching. In FIGS. 5 and 6, a molded part 54 · aluminum alloy (or other ductile, extrudable material) is shown, the edge flanges and a ^ is eist therebetween extending central portion 76 to v /. The central portion itself has three ribs 57 and is cut separately so that it has multiple rows of slots 58 (four rows are shown), the slots of each row being offset from and overlapping the slots in the next adjacent row. (In some cases, the rows are divided into pairs of rows of side-by-side slots in which the slots are offset from one another, but side-by-side rows of adjacent pairs have the slots transversely aligned).

]? ig. 8 shows how the workpieces between the tools 61 are clamped, which are carried on corresponding tool mountings 26. The lower tool holder 26 is direct with the piston rods of cylinder 2? connected by the bracket 5 "ΐ, as described above, while the plant holder 26 is pivotably mounted on pivot pins 62 (FIGS. 3 and 4). The upper tool holders 26 can by tool clamping cylinders 63 are lifted up and out of the lower tool holders 26, the clamping cylinder

4Ο982θ7θΪ39

pivotally attached to the lower tool holder 26 and with the upper tool holders 26 by a lever arm 64 and Connecting joints 65 are coupled.

In order to limit the bending of the planes 55 of the workpiece 54, it is desirable that these planes be clamped in place. Therefore, rear clamp cylinders 68 are used in addition to the tool clamp cylinders. A rear clamping cylinder is each pivotably connected to one of the tool holders 26, and the clamping of the flanges is effected by longitudinally movable clamping rods 69 which are coupled to the lower tool holder 26 by several short pivoting links 70, each link 70 at one end at the Tool holder and is pivotally connected at the other end to the clamping rod. This arrangement enables the workpiece to be inserted and removed quickly and the workpiece flange flanges to be jammed. The control device for the cylinders has corresponding valves 73 for the cylinders 63 and 74 for the cylinders 68, the valves being solenoid valves. The valve 74 is controlled, among other things, by a limit switch 75 (FIG. 14). The limit switch 75, when actuated, reverses the valve 74 when the workpiece is inserted; or should be removed. It is therefore a common cam operated limit switch. However, this is not shown in FIG. 1 to simplify the illustration. The cylinders 63 are either manually operated by the switch 76 or alternatively operated by a timer 77. The function of the timer is in the. described below in connection with the stretching of mesh material.

As can be seen from Fig. 14, an electric motor 80 is mechanical coupled to two pumps, the pump 81 being the main stretching cylinders 27 and the pump 82 being the cloning cylinders 63 only and 68 dines. In both cases an overload valve 84 is provided, to protect the system against overpressure. (In practice, two more tandem pumps are provided, one independent control of the stretching cylinders, the clamping cylinders 68

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and control the final stretch cylinder. For the sake of simplicity, these are Pumps not shown).

From E ¹ Ig. 7 it can be seen that the central ribs 87, which are not directly connected to the edge flanges 55, are not stretched, while the other ribs are stretched when the edge flanges 55 move apart. In order to bring about the required stretching, the workpiece end clamps 45 are therefore provided. In FIG. 7 only two middle ribs 87 are shown, which are connected to one another by a web section 56. Referring to Fig. 1, a more complicated arrangement is shown in which it is necessary to stretch four pairs of central ribs 87 (not shown). This is effected by the end clamps 45 which are actuated by the end stretching cylinders 46. The final stretching cylinders 45 are pivotably mounted so that they normally do not present an obstacle to the loading of the workpieces into the device. They can, however, be pivoted upwards so that the wedge 89 (Fig. 9) is in the same plane as the central ribs to be stretched, whereupon the cylinder 45 can be actuated to move the wedges inward and over the ones to be stretched Move ribs. Each pair of clamping wedges 89 are carried in a clamping block 90. The terminal blocks are connected to one another by toggle levers. The toggle levers themselves are connected to adjustable support blocks 92 by Zugstanaen 93, the arrangement being such that when the tie rods 93 are pulled backwards, the; Toggle levers 91 come to lie colinearly and are held in their colinear j positions by stop lugs 94 which are in one | grip differently. Characterized the pairs of ribs 87 are placed properly j according to (which would otherwise tend to close examples [to each other). The pegs 96 (FIG. 9) engage in the spaces between the respective ribs to aid in the precise arrangement of the pairs of ribs. The holding blocks 92 are adjustably arranged in a cross bar 97 by means of bolts 98, the heads of which lie in an S-slot 99.

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The clamping wedges 89 are pressed against ramp surfaces in a clamping block 90 by springs 102. However, these springs can be compressed and the clamping wedges 89 can be released by actuating a release handle 103. Everyone free _; handgrip is pivotably mounted about a pin 104 and: has a finger 105 which abuts the ends of the wedges 89 (FIG. 9). .

The FIGS. 10, 11, 12 and 13 show the means and the method after which the device for spreading material to a

Lattice shape is used, wherein the tails or web portions 57 are bent rather than stretched. The bending (without significant stretching) can only take place if the length of the grid panel can be shortened while the width increases. This is achieved in that a guide 110 with a slot 111 is attached to the lower tool holder 26, guides the rollers 112 on the slide 113 and etches them off. A carrier hook 114 is clamped onto each slide 113 and engages the edge of a grid panel (ie, on a part of the belt 57) (FIG. 11). Several carriages 103 are arranged in a line in each guide, the middle carriage being arranged in a stationary manner and the other carriages being movable with respect to this carriage. They are connected to one another by a flexible cord 116 which, when stretched, holds the sledges at equal distances. In order to accurately set these positions at the upper of the two Werkseughalterungen 26 a provided outwardly standing Nodenplatte 117 _(Fig.: 13) · recesses 118 engage the ifockenplatte 117 via respective slides 113 "to bring them exactly in position. ; This enables the workpiece to be hooked onto the hook 114 '. In order to ensure that the end product ■ has a uniform pattern over the entire surface, the carriages 113 are of such a length that they position of the panel on the workpiece are in contact with each other. As the hooks 114 move towards one another, the line 116 flexes, as shown in FIG. 12. I.

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The following is a summary of the operational sequence when a workpiece is through. Stretches to be spread apart (Figs. 1 to 9):
! ■

y A. All pumps are idling, the guide jaws are in their innermost position, with the jaws open and the support bracket released.

; B. A section of material provided with clasps is provided by inserted from the end or from above.

; C. The jaws and the support bracket close through Manual transmission.

D. The stretch cycle is initiated and completed. the Jaws are released so that no more tension remains on the section of material being machined. All Valves are brought to their middle position so that the main stretch cylinders are locked at this point.

E. The final stretching device is actuated and switched off.

P. The tension is relieved from the main stretching cylinders (by manual control).

G. The uterine support glue and jaws are released (by manual transmission).

H. The stretched product is removed.

I. The machine is reset to the starting position.

The following summary of the operational sequence applies to the Pail that the workpiece is to be spread open by bending (ilgn. 10 to 13):

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j The device is switched from stretching to bending

j of a selector switch (not shown).

i A. All pumps run freely. The attacking on the material section Hooks are positioned and removed from the

■ Holding plate 118 held.

; B. The pre-slit injection-molded workpiece is attached to the hook arranges.

: C. Bending is started. A timer delayed ^! the main stretch cylinder back to the retaining plate 118! is pulled, whereupon the bending cycle is carried out up to the release position.

D. The grid is removed.

E. The hooks are reset by the fact that the upper Jaws and the holding plate 118 can be switched by hand.

i ¹ . The device is reset.

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Claims (1)

Patent claims (1.) Method for spreading a workpiece, the two under Spaced, parallel edge sections, a material web between the edge sections and several rows of slots in the web of material, the slots of each row opposite the slots of at least one adjacent row are arranged offset and this overlap, characterized in that tools on corresponding Tool holders of a device for spreading Can be assembled from metal that a hand-operated Valve control device is actuated to further move the movable tool holder from its initial position to move inside that the edge portions of the workpiece attached to the corresponding tools v / earth that Adjustment cylinders are actuated to adjust the edge section o to separate and to deform the parts of the grid which are separated by the slits, and that after deforming the workpiece by the initial inward movement the movable tool holder is relaxed, and that the deformed and relaxed workpiece from the tools is removed. 2. The method according to claim 1, characterized in that according to the ends of the grid sections to relax the workpiece be detected with the wedges that a pressure medium is delivered to the cylinder, which is coupled to the clamping wedges are to actuate the cylinders and extend the grid sections that the clamping wedges are removed from the workpiece and that the workpiece is then removed from the tools. 3. Method according to claim 1 or 2, characterized in that that the attachment of the elongated parts of the workpiece 409820/0239 on the corresponding tools is that the Randal) cuts are pinched between the tools, and that the deformation of the grid sections in one Stretching and bending the grid sections consists. 4-. Method according to claim 1 or 2, characterized in that that the attachment of the edge portions of the workpiece to the corresponding tools consists in that the hand of the workpiece can be arranged via hooks on corresponding slides, which can be moved along the tool holders are that the tool holders are moved away from each other to thereby bend the workpiece parts, and that at the same time the carriages are moved towards each other until they attack each other, whereupon the relaxation and removal of the workpiece is carried out by the tools. 5 device for spreading a metallic workpiece, which has spaced, parallel edge sections, in particular for carrying out the method according to one of claims 1 ib-s 4-, wherein the device has a longitudinal direction extending part and transversely to this extending carrier, workpiece tool holders, which of the carriers are supported and extend in the longitudinal direction, a plurality of fluid-actuated cylinders on the Has frame and devices that couple the cylinder to the tool holder, so that upon actuation of the Cylinder the tool holder is moved over the carrier, characterized by: a valve device (30) and pressure medium lines (31) »ί the valve device with the cylinders (27) coupled \ whereby actuation of the valve means causes the actuation of the cylinder S a first and a second valve control device (33 »37) i on the frame (21), which are coupled to the valve device (30) by coupling devices, 409820/0239 a first, adjustable stop (34-) from the movable Tool holder (26) is carried and cooperates with the first valve control device (33) to provide a . Reversal of the adjustment direction of the cylinder (27) at the end of the outward movement of the tool holder (26) to effect a second, adjustable stop (38) which is also carried on the movable tool holder (26) and cooperates with the second valve control device (37) in order to terminate the actuation of the cylinders (27) after the initial inward movement of the movable tool holder (26), and by hand-operated valve control devices (4-1,4-2) to to cause further inward movement of the tool holder. 6. Apparatus according to claim. 5> characterized in that the valve device is a three-position solenoid valve (30) which is arranged so that upon energization of one of the two solenoids, the cylinders (27) for movement the tool holder (26) is actuated to the outside, and that when the other solenoid is energized, the cylinders (27) is actuated to move the tool holder (26) inwards, and that when both solenoids are de-energized the cylinders are switched off and that the first and second valve control devices limit switches (33) and (37) which are fastened to the frame (20), the coupling devices having electrical conductors, with the limit switches (33 »37) and the ent- ι speaking solenoid are connected, and wherein the adjustable stops (34 ·, 38) limit switch actuators! are stealing. -19- 409820/0239 - ι J. - 7. Apparatus according to claim 5 or 6, characterized in that that each tool holder (26) is a movable tool holder, and that two rows of cylinders (27) are provided are, each tool holder (26) having a horizontally movable part, which is connected to the piston rods of the cylinder of the corresponding row is connected, and has a pivotably mounted section which is supported by pivoting means is coupled to the horizontally movable section, and that clamping tools to the corresponding Tool holder sections of each tool holder are attached, with further, pressure medium-actuated cylinder Form tool clamping cylinders and the horizontally movable 'and pivotably mounted sections of the tool holder (26) couple together to clamp the workpiece tape sections between corresponding pairs of tools. 8. Device according to one of claims 5 to 7> characterized in that two clamping rods (69) are provided which are coupled to the corresponding tool holder (26) by a series of pivoting links (70) bh in order to move the clamping rods in a horizontal direction to effect level, and that corresponding, further, fluid-operated cylinder (68) coupling the clamping bars (69) with the corresponding workpiece to prevent movement of the clamping ^rods from outer positions to the inside of the tools on the respective workpieces to move. 9. Device according to one of claims 5 "to 8, marked j net through another pair of workpiece end clamps (90) » which is arranged in each case at each end of the frame (20), and by further pressure medium-actuated cylinders (46), the Represent the end stretch cylinder and the end brackets (90) irit connect the respective ends of the frame (20). -20- 409820/0239 10. Apparatus according to claim 9> characterized in that Each end stretching cylinder (46) has a pivot bracket by which it attaches to the corresponding end of the web " is. 11. The device according to claim 9 or 10, characterized in that each end clamp (90) has two clamping wedges (89), which are slidable in a mounting block and attack outwardly converging surfaces in the mounting block can, so that the clamping wedges in an outward direction Movement of the assembly block firmly grasp a workpiece, - with which they are engaged. 12. The apparatus according to claim 11, characterized by a plurality of toggle levers (91) which the end brackets (90) at each end of the Eahmens (20) connect with each other, wherein a cross rod with the piston rod of the respective end stretching cylinder (46) is connected and tie rods (93) the corresponding mounting blocks of each end of the frame (2i) with the cross rod associate. 13. Apparatus according to claim 7, characterized by two Guides (HO), facilities to the guides (110) with the corresponding, horizontally possible sections of the tool holder (26) to connect a series of carriages (113), with lobes on the carriage on guide surfaces attack in the guide (HO), a flexible line that holds the carriages (113) on each of the guides (110) are carried to connect to each other, and by inwardly directed hooks engaging the workpiece (114) on each carriage (113). 14. The device according to claim 13, characterized in that the lengths of the carriages (113) are the same size and also the same is the hole spacing on a workpiece after it has been spread apart, and that the carriages (113) with their ends against one another can be initiated and arranged. ι 409820/0239 Device according to. Claim 1J or 14-, characterized by an IT cam plate on the pivoting section of each corresponding one Tool holder (26), each cam plate having a series of beveled mouth recesses which are each so large that they can accommodate a hook between their side edges, and are arranged so that a downward pivoting movement of the cam plate when this is actuated by the tool clamping cylinder causes the carriage (113) in an arrangement with equal gaps from each other. 16. Apparatus according to claim 15> characterized in that another solenoid valve, further pressure lines that connect the other valve with the tool clamping cylinders, a manual control switch and a timer control switch, both with the additional solenoid valve are connected and can complete the power supply circuit for the valve independently of one another. 409820/0239 Blank page