WO1996009917A1

WO1996009917A1 - Device for bending wire-type materials

Info

Publication number: WO1996009917A1
Application number: PCT/EP1995/003827
Authority: WO
Inventors: Günther W. ORTLEPP; Karl-Ernst Schubert; Gerd Schmidt
Original assignee: Ortlepp Guenther W; Schubert Karl Ernst; Gerd Schmidt
Priority date: 1994-09-27
Filing date: 1995-09-27
Publication date: 1996-04-04
Also published as: DE4434513C1; DE9416512U1; AU3743495A

Abstract

A device is proposed for bending wire-type materials. The device is used to bend a length of wire (3) passed through a batch for stapling (1) towards the latter; with a further movement of the length of wire (3) towards a backstop (30), after entering the batch for stapling (1) the wire is bent towards the batch for stapling (1) by a bending jaw (20) which acts laterally on the length of wire (3), is mounted on a stapling batch support (10) so as to rotate, and pivots when the stapling batch support (10) moves towards the backstop (30); at the beginning of and during a bending operation, an acting surface (23) of the bending jaw (20) pointing towards the wire length (3) to be bent extends substantially parallel to the length of wire (3). The proposed device is particularly suitable for machine and manual stapling operations.

Description

Device for bending wire-like materials

The present invention relates to a device for bending wire-like materials, a piece of which has been driven through a good, for example a textile material, cardboard or paper. In particular, it is a device for bending staples.

Particularly when stapling a stack of sheets of paper together, the problem arises that a staple used for this purpose is bent into a bulbous shape during stapling, as a result of which the staple increases the thickness of the staple. The fewer sheets are stapled together, the greater the thickening of the stapled paper stack caused by the staple. In a file folder, a collection of sheets stapled in this way takes up considerably more space than would correspond to the pure paper thickness. The bulbous shape of the curved staple is due to the fact that the Typically used staplers, the staple is pressed against oblique guide surfaces after piercing the staple, which are simply recessed or embossed in a base plate of the stapler.

In order to place the staple as flat as possible on the staple, the use of pivotable bending jaws is known, with which the legs of the staple driven through the staple are bent and pressed flat against the staple. Corresponding bending devices are known from WO 90/08015, WO 94/00277 and DE-PS 646 864.

In the bending device according to WO 90/08015, the bending jaws are rotatably mounted in a storage material support on which the storage material rests. To bend the staple, the bending jaws are pivoted against the legs of the staple driven through the material to be stapled. For this purpose, a counter bearing is pressed against the material to be handled and thus against the bending jaws during the stitching process. The bending jaws are shaped on their surface facing the counter bearing in such a way that they are pivoted against the legs of the staple driven by the object to be pressed by pressing the counter bearing onto the object to be tacked, bending the legs in the process and pressing them flat against the object to be tacked. The surface of the associated bending jaw acting on a clamp leg is at an angle to this leg at the beginning of the bending process. The bending process is initiated in that the leg is pressed against the oblique active surface of the bending jaw already while it is still being driven through the material to be bound, or the bending jaw is already forced into a corresponding pivoting movement against the staple leg. This inevitably involves excessive wear on the active surface of the bending jaw, with the result that, after a short use, a clean bending, ie a flat pressing, of the staple leg against the material to be stapled is no longer guaranteed. The bending force, which naturally has to be greatest to initiate the bending process, is applied at this very critical moment at the tips of the staple legs. The bending of the staple legs is accordingly poorly defined. According to WO 94/00277, the pivotable bending jaws are not rotatably mounted in the magazine support, but in the base plate. These known bending jaws are pivoted by means of additional pivoting means which are guided against the bending jaws during stapling. The bending jaws are equipped with corresponding sliding surfaces, along which the pivoting means slide, forcing the bending jaws to pivot. To initiate the bending process, the clamp legs must slide with their front tips on oblique active surfaces of the bending jaws in this known device as well. When bending further, the bending jaws press like cams against the clamp legs. By means of so-called post-compression, the staple legs are to be pressed particularly firmly onto the staple. This known bending device is structurally complex and is subject to the heavy wear already described.

The stapler known from DE-PS 646 864 is similar to that of WO 90/08015. The booklet support is moved during stapling against the force of springs to a counter bearing for the bending jaws, and the bending jaws rotatably mounted in the booklet support slide against the counter bearing, so that they are pivoted against the clamp legs driven by the booklet. The bending of the staple legs begins after all or most of the staple legs have been driven through the material to be stapled. However, even in this known device, the staple legs driven through the material to be bumped with their tips at the beginning of the bending process against the oblique active surfaces of the bending jaws. The above-mentioned problems of wear and undefined bending of the clamp legs therefore occur again, precisely at the beginning of the bending process.

In a stapler known from DE-PS 610274, the staple legs are also bent by bending jaws. Although these have parallel active surfaces to the clamp legs at the start of the bending process, the active movement of the jaws is such that the clamp leg is bent over a corner of the bending jaw. The bending jaws act like cams that slide along the clamp legs when they are bent. It is the object of the present invention to provide a device for bending a wire-shaped material which is subject to little wear and ensures clean bending of the staple.

This object is solved by the subject matter of claim 1.

The dependent claims are directed to advantageous, not smoothly self-evident embodiments of the invention.

Claim 16 relates to the use of the object of the invention for bending staples.

To bend a wire-like material, a piece of the material is driven through a stitching guide. With a further movement of the piece of wire, which is partially or completely driven by the stitching guide, in the direction of a counterbearing, a bending jaw, which is rotatably mounted on or in a, preferably movable, item to be handled, on which the item to be placed rests, is rotatably mounted together with the support in Moved towards the counter bearing and pressed against this counter bearing. As a result, the bending jaw is forced to pivot. During the pivoting movement, it acts from the side on the piece of wire driven through the material and bends this piece of wire toward the material. The same effect can be achieved by pressing the counter bearing towards the bending jaw.

According to the invention, an effective surface of the bending jaw which presses against the piece of material to be bent has already at the beginning of the bending process and during the bending process essentially parallel to the piece of wire. This prevents the tip of the wire piece from pressing against the active surface of the bending jaw, particularly in a critical phase of bending, namely when the bending process is initiated. The wear of the bending jaw is reduced compared to the known bending devices. Due to the parallel guidance of the bending jaw, the piece of wire is guided evenly through the active surface of the bending jaw. The bending forces acting on the piece of wire are distributed over the length of the piece of wire upset. The lateral forces acting on the tip of the piece of material can be lower than in the known bending devices because of the use according to the invention of the entire length of the piece of material which is driven through the material. Forces acting vertically on the tip of the piece of wire, which inevitably occur in the case of inclined bending jaws and counteract the driving in of the piece of wire, are completely avoided.

The advantages mentioned come into play to a particularly great extent if a pivoting and thus an active movement of the bending jaw on the wire piece only takes place after the wire piece has been essentially completely driven through the material and thus from the beginning of the bending process to the entire length of the the piece of wire to be driven is available for applying the bending force.

According to a particularly preferred embodiment of the invention, the axis of rotation of the bending jaw is close to the point at which the wire piece emerges from the item to be stitched, preferably as close as is structurally possible. In cooperation with the fact that the piece of wire has been driven completely or essentially completely through the material before the initiation of the bending, the maximum available length for applying the bending force. Due to the bending jaw running parallel to the piece of wire and close to the exit point, an optimal bending with the application of force over the entire free length of the piece of wire and minimal relative movement between the piece of wire and the bending jaw and thus minimal wear of the active surface of the bending jaw is possible. The bending jaw lies uninterrupted until the end of the bending process parallel to the piece of wire, so that it can be optimally applied to the material. If the piece of wire is a conventional staple, the entire staple is additionally compressed by the effect of post-compression if, after the leg of the staple has been completely bent, the leg is additionally pressed against the opposite staple.

The bending jaw is pivoted about its axis of rotation by moving the item support onto the counter bearing. The counter bearing can simply be a base plate of the Act bending device or a counter bearing, which is provided with a sliding guide for the bending jaw. The bending jaw is particularly preferably moved towards such a sliding guide when the stacking material support moves against the base plate and is pivoted in the desired direction by the sliding guide. The bending jaw itself has a suitable counter surface to the sliding guide on the opposite side. The sliding guide and counter surface are designed so that the bending jaw slides as gently as possible.

It is also advantageous, for example, to pivot a coupling rod both on the base plate mentioned and on the bending jaw. Such a rigid coupling rod would rotate about its axis of rotation on the base plate side due to the movement of the item support and, because of its rigid design, would pivot the bending jaw about its axis of rotation in the desired direction.

The item to be handled can preferably be moved towards the counter bearing against a resilient restoring force. This design contributes to the fact that the device according to the invention can also be used for smaller staplers, in particular hand staplers, in which a motor-driven resetting of the material support and counter bearing would be too expensive.

In order to allow movement of the item to be handled towards the counter bearing and thus pivoting of the bending jaw only when the wire piece has been driven essentially completely through the item to be handled, a means for generating the restoring force can advantageously have a degressive characteristic. In this case, the characteristic curve is adjusted so that the restoring force increases only slightly from the pressure necessary to almost completely penetrate the staple.

In an advantageous embodiment, a locking device is provided, which is preferably arranged between the item support and the base plate of the device, which is triggered first to release a movement of the item support in the direction of the counter bearing. Because such a locking device is only to be triggered, a defined release can be carried out exactly at the desired time, preferably when the piece of wire is essentially chen has been completely driven through the item to be achieved.

Advantageously, a plunger is rigidly attached or fixable to an upper part of the bending device and acts on the locking device through the material to be pasted or laterally past the material to be bound when the upper part is in a corresponding position in which the piece of wire is essentially completely driven through the material to be bound is located.

While in this first variant of a locking device a first locking means and a second locking means blocking its movement are held in their locking position essentially by a form fit, in a second variant the locking effect of the two locking means is based on a force fit, in such a way that the second locking means by a restoring force constantly acting thereon is held in a blocking position in which it prevents a movement of the first blocking means and thus a movement of the material support and the counter-bearing towards one another, as long as a predetermined force, preferably the force required to drive the piece of wire through the material to be handled, is not exceeded. In the second variant, the second locking means can in particular be arranged so as to be slidable or pivotable. The second locking means can also act advantageously on a leaf spring, which must be bent, so to speak, by the first locking means against its internal restoring force. The first locking means must particularly preferably penetrate between two such leaf spring-like locking means and thereby bend them apart.

If the item to be handled is fixed in relation to the counter bearing when the wire piece is driven in, a locking device can also be dispensed with; At the given point in time when the pivoting movement of the bending jaw is to be initiated, for example, a motor can be controlled with which the item support and the counter bearing can be moved towards one another.

According to a further preferred embodiment of the invention, a bending die is arranged in the booklet support which supports the wire piece driven by the booklet at its exit point with one edge, so that the wire piece as a result of the pivoting movement of the Bending jaw is bent exactly around this bending edge of the bending die. The bending die is moved out of the bending area during the bending process, in particular towards the end of the bending process, in order to enable the bent wire piece to be pressed flat.

The bending die can be designed in one piece or in several pieces. In an embodiment of the bending edge, it preferably has an acute-angled side surface facing the wire piece at an end supporting the piece of wire. The bending die, particularly in one-piece design, is preferably tapered along its bending edge in the direction of its end supporting the piece of wire. As a result, the bending die can easily be moved out of the bending area again. In a one-piece design, the bending die can have a plurality of bending edges, preferably two bending edges. The bending die is preferably straight in the magazine support, but can also be advantageously pivoted out of the bending area. If several pieces of wire are to be bent at the same time, for example the two legs of a U-shaped staple, the bending die can also be formed in several pieces, in the example, two pieces, each of the die pieces with its bending edge being assigned to one of the wire pieces or clip legs to be bent . The individual die pieces are advantageously movable in relation to one another, in particular pivotable relative to one another, arranged in the magazine support.

The locking device, the bending die and other embodiments of a bending device according to the invention can be used not only advantageously with the claimed parallelism of the bending jaw, but also in some other way individually or in combination with one another.

Exemplary embodiments of the invention are described with reference to the following figures. Further features and advantages of the invention are disclosed. Show it:

FIG. 1 shows a bending device in cross section at the beginning of the bending process,

FIG. 2 shows a partial section of the bending device according to FIG. 1 during the bending process,

3 shows the partial section of FIG. 2 after the bending process,

FIG. 4 shows a bending jaw, FIG. 5 shows a bending device with a first locking device,

FIG. 6 shows a bending device with a bending die in cross section,

FIG. 7 the bending die of FIG. 6,

FIG. 8 shows a bending device with coupling rods in cross section,

FIG. 9 shows a bending device with a second locking device,

FIG. 10 shows a bending device with a third locking device,

FIG. 11 shows a bending device with bending jaws that can be pivoted apart,

FIG. 12 shows the bending device according to FIG. 11 after the bending process,

13 shows a stapled item stapled with the bending device according to FIG

Figure 14 shows an arrangement of bending jaws for inclined bending.

The exemplary embodiments shown in the figures are devices for bending staples.

As shown in FIG. 1, a item 1 lies on a item support 10 which is supported by springs 4 against a base plate 40 of the stapler. A U-shaped staple 2 has essentially been driven completely through the staple. Two bending jaws 20 are rotatably mounted symmetrically opposite the outer sides of the two legs 3 of the staple 2 in the material support 10. The bending jaws 20 can each be pivoted about an axis of rotation 26 which lies very close to an exit point 5 at which the staple leg 3 pushes through the item 1 to be stitched. Shortly before the bending process is initiated, a surface 23 facing the clamp leg 3 - hereinafter referred to as the active surface - extends parallel to this clamp leg 3. Each bending jaw 20 hangs with its vertically extending active surface 23 without jamming against its clamp leg 3 in its bearing about the axis of rotation 26. The active surfaces 23 of the two bending jaws 20 are spaced as closely as possible from their respective clamp legs 3.

A counter bearing 30 is fastened on the base plate 40. The counter bearing 30 is bowl-shaped in cross section with two guide surfaces 34 provided symmetrically to the two sides of a flat bottom 33. A guide surface or guide 34 is in each case a bending cheek facing 20. Each of the bending jaws 20 has a sliding surface 24 facing its associated guide 34 a counter bearing 30, with which it slides on the corresponding guide 3 when it is pressed against the counter bearing 30 as a result of the movement of the item support 10 on the base plate 40. The sliding surface 24 and the guide surface 34 run obliquely to the piercing direction of the staple 2. This in particular facilitates the initiation of the sliding movement and thus the pivoting movement of the bending jaw 20. In the exemplary embodiment, the sliding surface 24 of the bending jaw 20 is rounded, preferably rounded in the form of a segment of a circle, while the guide 34 on the thrust bearing 30 extends in a straight line at an angle.

2 shows the state during and in FIG. 3 at the end of the bending process. The leg 3 of the staple 2 is completely bent in Figure 3 and pressed flat against the staple 1. The bending jaw 20 lies with a rear surface 25 parallel to its active surface 23 between the guides 34 on the counter bearing 30, so that in this state the already completely bent clamp leg 3 is pressed flat against the item 1 to be handled. A rear surface 28 of the bending jaw 20 facing the opposite-side guide 34 when the clamp leg 3 is bent over, is beveled in such a way that the bending jaw 20 comes to lie at a certain distance from the guide 34 and thus freely therefrom and through the counter-bearing 30 only in the vertical direction the staple 1 is pressed. An additional pressing after bending the clamp leg 3 to achieve post-compression is possible. For this purpose, the counter bearing 30 can advantageously point obliquely in the area in which the bending jaw 20 rests in the direction of the item support 10. This also applies to the device according to FIGS. 11 and 12.

FIG. 4 shows an embodiment of a bending jaw 20, the axis of rotation 26 of which is as close as possible to the exit point 5 (FIG. 1) of the clamp leg 3. In order to make the rotary bearing of the bending jaw 20 as small as possible, the bending jaw 20 is guided and held in a backdrop during its pivoting movement. For this purpose, the bending jaw 20 is provided on both sides with a rail 27 in the form of a segment of a circle, which is slidably guided in a corresponding support-side guide groove. Through the formation of a The axis of rotation 26 of the bending jaw 20 can be placed as close as desired to the exit point 5 of the clamp leg 3, preferably in the edge of the bending jaw 20 close to it. A conventional rotary bearing, for example by means of a bolt accommodated in one eye, can also be used with advantage.

5 shows a hand stapler with a first embodiment of a locking device in longitudinal section. With the locking device it is achieved that the item support 10 can only be moved toward the base plate 40 of the stapler when the legs 3 of the staple 2 have been driven completely through the item 1. By pressing an upper part 50 of the hand stapler, the foremost staple 2 located in a staple magazine 54 arranged in the upper part 50 is driven through the staple 1 by means of a driver 53. Up to this point, a locking device with a support 14 fastened to the underside of the item support 10 as the first locking means and a rocker arm 44 rotatably attached to the base plate 40 about an axis 47 as a second locking means prevent the item support 10 from moving in the direction of the base plate 40 . The rocker arm 44 has approximately the shape of an "L" with a first leg 45 which, in the blocking position, is essentially perpendicular to the material support 10, and with a second leg 46 which extends approximately parallel to the material support 10 in the blocking position The point of intersection of these two legs 45 and 46 is the axis of rotation 47 of the rocker arm 44. Furthermore, the rocker arm 44 has an extension 48 on the side of the rocker arm axis of rotation 47 facing away from the two legs 45 and 46. The extension 48 forms a stop to hold the rocker arm 44 against the force of a return spring 49 in the locked position. The support-side support 14 is arranged opposite the first leg 45 and approximately extending this leg 45. The first leg 45 and the support-side support 14 abut against one another in the locked position and in this way prevent movement of the material support 10 toward the base plate 40.

This locking device is triggered by means of a release pin 42 which is slidably received in a support-side guide 12 so that it comes to rest under the item 1 with one end and with the other end on the opposite side Presses end against the second leg 46 of the rocker arm 44. In the exemplary embodiment, the guide 12 and thus the movement of the release pin 42 run perpendicular to the support surface of the item support 10. However, deviating orientations of the direction of movement of the release pin 42, which are oblique to the item support 10, are in principle possible if a modified construction of the locking device requires this . In the locked position, the release pin 42 protrudes a little beyond the support surface of the item support 10 with its support-side end. The protrusion of the release pin 42 and the spring force of the return spring 49 are so matched to one another that the weight of the item 1 pressing on the release pin 42 and the usual vibrations of the stapler cannot trigger the locking device. To trigger the locking device, a plunger 52 is also rigidly attached to the upper part 50 of the stapler. Only when the staple 2 has been driven essentially completely through the staple 1 by the driver 53 does the plunger 52 press vertically onto the staple 1 from above. The plunger 52 is arranged on the upper part 50 in such a way that it now connects to the release pin 42 lies opposite and extends it. With further pressure on the upper part 50, the trigger pin 42 is pressed by the pressure of the plunger 52 on the second leg 46 of the rocker arm 44. The rocker arm 44 is thereby tilted against the force of the return spring 49 about its axis of rotation 47, so that the first leg 45 of the rocker arm 44 is moved out of the line of motion of the support 14 on the support side. After this triggering of the locking device, the item support 10 can be pressed pivoting about its axis of rotation 11 in the direction of the counter bearing 30 or the base plate 40. This movement of the booklet support 10 takes place against the restoring force of the spring 4, which presses the booklet support 10 back into its locked starting position after stapling has taken place.

In most applications, the pressure of the plunger 52 through the item 1 is sufficient to trigger the locking device. In the case of particularly large staplers or stationary stapling devices, such a plunger 52 can, however, be arranged on the upper part 50 such that it acts laterally past the stapled material 1 on a correspondingly arranged release pin 42.

As can be seen in Figure 5, a bending device according to the invention with the for Handheld staplers can be combined with common tops. Especially when stapling with staplers, which naturally only use comparatively thin stacks of paper, the advantage of bending the staples flat is particularly evident. The axes of rotation 11, 51 and 55 of the magazine support 10, upper part 50 and magazine 54 can also coincide.

FIG. 6 shows a stapler with a bending die 60, which is also shown in perspective in FIG. 7 alone. The bending die 60 protrudes with one end between the two staple legs 3 of the staple 2 driven through the staple 1. At this end, the bending die 60 has a trapezoidal cross-section. An upper surface of the bending die 60, which faces the underside of the item support 10, extends with its acute-angled side edges 61 in each case as close as possible to the two clip legs 3. From the side edges 61, the two side surfaces 62 of the bending die 60 facing the clip legs 3 are the narrower one of them Base plate 40 beveled facing surface. Due to this trapezoidal shape, the bending die 60 provides support to the clamp legs 3 when the bending process is initiated, so that the clamp legs 3 are bent exactly at the respective exit point 5 (FIG. 1) by the pivoting movement of the bending jaws 20. This results in a sharp kink; at the same time bending of the staple 2 at the staple corners and thus in the staple 1 is prevented, so that the staple between the two staple legs 3 cannot warp during bending.

The bending die 60 shown in Figure 6 is slidably straight in the staple 10, with its direction of movement perpendicular to the cutting plane shown, i.e. parallel to the axes of rotation 26 of the bending jaws 20.

After the clamp legs 3 have been bent near their exit points 5 (FIG. 1), the bending die 60 is moved out of the bending area by a suitable mechanism in order not to hinder further bending. The movement is coupled in a suitable manner to the movement of the item support 10. In order to make it easier to move the bending die 60 out of the bending area, the bending die 60 of the exemplary embodiment, ie the straight-moving bending die 60, is directed in the direction along its side edges 61 tapered on its end facing the bending area. This is shown more clearly in FIG. 7.

An alternative pivot mechanism for the bending jaws 20 is shown schematically in FIG. In this exemplary embodiment, the bending jaws 20 do not slide off on guides formed in a counter bearing, but are articulatedly connected to coupling rods 74. A coupling rod 74 is pivoted at one end to the base plate 40 and pivoted at the other end to the bending jaw 20. The two axes of rotation run parallel to the axis of rotation 26 of the bending jaw 20. The bending jaws 20 are pivoted by their respective coupling rods 74 due to the movement of the item support 10 on the base plate 40.

Figure 9 shows a second embodiment of a locking device. The first locking means is again formed by a support 60 which is rigidly attached to the item support 10 and protrudes therefrom in the direction of the base plate 40. A slide 62 forms the second locking means. The slide 62 is slidably guided in a bearing block 65 seated on the base plate 40 in a direction approximately at right angles to the direction of movement of the support 60. In the illustration in FIG. 9, the slide 62 is in its blocking position, into which it is held by an elastic Restoring force is biased. For this purpose, it is pressed against the bearing block 65 by a compression spring 66, which is supported on the base plate 40 in the case of a support 67. The threshold of the restoring force, i. H. the working point of the spring 66 is adjustable in the exemplary embodiment and is set so that the staple leg is securely driven through a tack material of the preset maximum thickness before the locking device is triggered. As long as this threshold value is not exceeded, the support 60 is supported on the slide 62; the two locking means are in the locked position. With a low spring preload, thin items can be stapled with little effort. If the pretensioning is greater, thicker material to be stapled can be stapled with a correspondingly higher effort.

At their mutually facing ends are the support 60 with an inclined surface 61 and that Slider 62 is provided with an inclined surface 63 which, when the locking device is triggered, namely when the threshold value is exceeded, slide against one another like two complementary, inclined planes against the restoring force of the spring 66. The two inclined surfaces 61, 63 point obliquely to the direction of movement of the support 60 and to the direction of movement of the slide 62 at an angle at which self-locking can be reliably avoided. The spring 4 brings the item support 10 back into the starting position after the bending process.

A further example of a non-positive or frictional locking device is shown in FIG. Here, too, the first blocking means is formed by a support 70, which protrudes from the item support 10 and is directed in the direction of the base plate 40. Opposite the support 70, two spring steel sheets 72.1 and 72.2 are fastened as second locking means on the base plate 40 and protrude therefrom in the direction of the support 70. So that a bending process can be carried out, the support 70 must overcome the prestressing force of the two spring steel sheets 72.1 and 72.2 and penetrate between the two. In principle, a spring steel sheet would also serve the purpose of blocking the movement of the support 70. Of course, other suitable materials can also be used instead of spring steel. Each of the spring steel sheets 72.1 and 72.2 acts like a leaf spring which, in the exemplary embodiment, has a cross section with a fastening foot 73, an angled arch part 74 and an angled outlet part 75 facing the support 70. Each arch part 74 is bent in a section facing its outlet part 75 to an imaginary line representing the direction of movement of the support 70. The two spring steel sheets 72.1 and 72.2 abut each other in the area of their bend between the curved part 74 and the outlet part 75 under a predetermined prestress. The outlet parts 75 form a funnel into which the support 70 with inclined surfaces 71 penetrates at its free, pointed end when the threshold force is exceeded at which the relative movement between the item support 10 and the counter bearing 40 is to start.

The outlet parts 75 are at an opening angle W apart, and the respective inclined surfaces 71 facing the outlet parts 75 are preferably essentially the same arranged in parallel so that the surfaces 71 and 75 slide on each other in the manner of inclined planes when the support 70 penetrates. The opening angle <. should be chosen so that self-locking is avoided. The tip of the support 70 can also be spherical. The locking device is triggered when the force with which the two arch parts 74 are braced against one another and the frictional force between the surfaces 71 and 75 are overcome.

The bending device according to FIG. 11 has bending jaws 20 which can be pivoted away from one another for so-called needling of a staple 1. Their mode of operation otherwise corresponds to the device shown in Figure 1, so that the corresponding, equivalent parts are designated by the reference numerals used there. FIG. 12 shows the bending device according to FIG. 11 after the bending process. FIG. 13 (below) shows a staple 1 stapled with the device according to FIGS. 11 and 12. The needling can further reduce the thickness of the staple 1 to be stapled, by making the active surface of the bending jaw 20 flush with the surface of the staple 10 after the bending process has been completed completes (Figure 12) and the item 1 is pressed outside to the height of the middle part of the clip 2. At the stapling point, the staple 1 so stapled is only one thickness plus a single piece of wire thickness, while, as shown in the upper part of FIG. 13, the thickness at the stapling point is one piece thickness plus a double piece of wire thickness. The staple legs 3, the staple 1 and the middle part of the staple 2 mutually overlap when stapled with the device according to FIGS. 11 and 12.

FIG. 14 shows an arrangement of two bending jaws 20 with which staples 2 with particularly long staple legs 3 can be bent flat even with thin staples. The bent clamp legs 3 are offset and overlapped in parallel, as shown in the upper part of FIG. 14. For this purpose, as shown in the lower part of FIG. 14, the axis of rotation 26 of each bending jaw 20 in the level of the product to be tacked does not point at right angles to the longitudinal axis of the middle part of the staple 2 lying on the product to be tacked. The angle of the deviation from the right angle is designated by β.

Claims

Device for bending wire-like materials

Claims

Device for bending wire-like materials, with which a piece of wire (3) driven by a material to be stitched (1) during a further movement of the piece of wire (3) in the direction of an abutment (30; 40) by one acting laterally on the piece of wire (3) , on a booklet support (10) rotatably mounted and when the booklet support (10) is moved towards the counter bearing (30; 40), the bending jaw (20) is bent towards the booklet (1), characterized in that one to the active surface (23) of the bending jaw (20) facing the piece of wire (3) to be bent at the beginning and during a bending process essentially parallel to the piece of wire (3). 2. Device according to claim 1, characterized in that a pivoting and thus an active movement of the bending jaw (20) on the wire piece (3) takes place only after the wire piece (3) substantially completely ge through the material to be stitched (1) has been.

3. Device according to claim 1 or 2, characterized in that an axis of rotation (26) of the bending jaw (20) is arranged near the exit point (5) of the wire piece (3) being driven by the material to be stitched (1).

4. Device according to one of the preceding claims, characterized in that the bending jaw (20) during a movement of the material support (10) on the counter bearing (30) by sliding on the counter bearing (30) in a pivoting movement about its axis of rotation (26) is displaced, the counter bearing (30) preferably being provided with a bevelled guide surface (34) for the bending jaw (20), along which the bending jaw (20) slides during its pivoting movement.

5. Device according to one of the preceding claims, characterized in that the item support (10) against a resilient restoring force on the counter bearing (30) is movable and a means (4) for generating the restoring force preferably has a degressive characteristic.

6. Device according to one of the preceding claims, characterized in that a locking device (14, 44; 60, 62; 70, 72.1, 72.2) is provided which for the Freiga¬ be a movement of the material support (10) and the counter-bearing (30th ) is triggered towards one another, the triggering preferably only taking place when the wire piece (3) has been driven essentially completely through the item to be stitched (1).

7. The device according to claim 6, characterized in that the triggering of the locking device (14, 44) by an on an upper part (50) of the device an¬ arranged plunger (52) through the stitched material (1) or on the stitched material (1) done over.

8. The device according to claim 6, characterized in that the locking device (60, 62; 70, 72.1, 72.2) is triggered against a preferably adjustable locking force, which is preferably greater than a force required to penetrate the piece of wire through the item to be stitched (1).

9. The device according to claim 8, characterized in that the locking device comprises at least a first locking means (60; 70) and at least one by the locking force in the locking position to the first locking means (60; 70) held second locking means (62; 72.1, 72.2), which act frictionally against one another when the locking device is triggered.

10. The device according to claim 8 or 9, characterized in that the second Sperr¬ means (62) movably arranged on the counter bearing (40) or the material support (10) and is provided with a sliding surface (63) which is oblique to the direction of it Movement and also to an imaginary line along which the first and the second locking means (60, 62) are moved towards each other, and along which the first locking means (60) slides when the locking device is triggered and thereby the second locking means (62) moved against its locking force from its locked position.

11. The device according to claim 10, characterized in that the second locking means (62) is arranged pivotably or slidably.

12. The apparatus according to claim 10, characterized in that the second locking means (72.1, 72.2) is tensioned like a leaf spring against the first locking means (70) when the locking device is triggered.

13. Device according to one of the preceding claims, characterized in that the axis of rotation (26) of the bending jaw (20) seen in the plane of the product to be handled does not point at right angles to the longitudinal axis of a part of the piece of wire (3) lying on the product to be handled (1).

14. Device according to one of the preceding claims, characterized in that at least two pairs of bending jaws (20) are provided, which can optionally be used for bending, preferably at least one of the pairs to each other and at least another of the pairs of pivoting bending jaws ( 20). a bending die (60), which has an edge (61) with which it supports the piece of wire (3) driven by the item to be baked (3) at the beginning of the bending process, is arranged on the item to be stacked (10), so that it is located directly at the exit point (5) is bent and which is moved during the bending process, in particular towards the end of the bending process, out of the area of the wire piece (3), so that the wire piece (3) can be completely bent over.

16. Device for bending staples, in particular hand stapler, characterized ge indicates that a device for bending wire-like materials according to one of the preceding claims is used.