DE4434513C1 - Device for bending wire-type materials - Google Patents

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

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

Especially when stapling a stack of sheets of paper together, the problem arises that a staple used for this is bent into a bulbous shape during stapling, as a result of which the Staple increases the thickness of the staple. The fewer sheets stapled together become, the more the thickening of the stapled caused by the staple falls Stack of paper in weight. In a file folder a collection of such claims stapled sheets significantly more space than it would correspond to the pure paper thickness. The bulbous shape of the curved staple is due to the fact that the  Typically, staplers used the staple after piercing the staple is pressed against inclined guide surfaces that are easy in a base plate of the stapler are exempt or shaped.

To use the staple as flat as possible on the material to be stapled, use pivotable bending jaws known, with which the leg driven through the goods to be handled the staple is bent and pressed flat against the material to be stapled. Appropriate Bending devices are from WO 90/08015, WO 94/00277 and DE-PS 6 46 864 known.

In the bending device according to WO 90/08015, the bending jaws are in one Storage material support on which the material to be stored rests rotatably. For bending the staple the bending jaws against the leg of the staple driven through the material to be stapled pivoted. For this purpose, a counter bearing is placed against the Material support and thus pressed against the bending jaws. The bending jaws are on hers the counter-facing surface so shaped that by pressing the Counter bearing on the item support against the leg driven by the item Staple be pivoted, bend the legs and flat against the material to be stapled to press. The area 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 will initiated by the fact that the leg is already being driven through the material to be stitched is pressed against the oblique active surface of the bending jaw or the bending jaw already forced into a corresponding swiveling movement against the staple leg becomes. This inevitably causes heavy wear on the active surface of the bending jaw connected, with the result that after a short use a clean bending, d. H. on flat pressing, the staple leg to the material to be bound is no longer guaranteed. The Bending force, which of course must be greatest to initiate the bending process applied at the most 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 in the material support,  but rotatably mounted in the base plate. These known bending jaws are by means of additional pivoting means pivoted against the bending jaws during stapling be performed. The bending jaws are equipped with appropriate sliding surfaces on which slide the pivoting means along and thereby force the bending jaws to pivot. To the Initiation of the bending process, the clamp legs must also be known in this Slide the device with its front tips on the inclined active surfaces of the bending jaws. When bending further, the bending jaws press like cams against the clamp legs.

By means of so-called post-compression, the staple legs should be particularly firmly attached to the To be tacked. This known bending device is structurally complex and is subject to the severe wear already described.

The stapler known from DE-PS 6 46 864 is similar to that of WO 90/08015. The Stitched material support is used for stapling against the force of springs on a counter bearing Bending jaws too moved, and the bending jaws rotatably mounted in the magazine support slide on the counter bearing, so that they are against the through the tack driven bracket legs are pivoted. The bending of the clamp legs begins after all or most of the staple leg through the staple have been driven through. However, those driven through the item to be bumped Bracket legs with this known device at the beginning of the bending process their tips on the oblique active surfaces of the bending jaws. So there are again already mentioned problems of wear and undefined bending of the clamp straight up at the beginning of the bending process.

In a further stapler known from DE-PS 6 10 274, the staple legs also bent over by bending jaws. These point out at the beginning of the Bending process parallel to the staple legs on effective surfaces, however, is the Active movement of the jaws so that the staple leg over a corner of the bending jaw is bent. The bending jaws act like cams that bend against the Slide the clamp legs along.

It is the object of the present invention to provide a device for bending a to create wire-shaped material that is subject to low wear and tear ensures that the staple is bent properly.

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

The dependent claims are advantageous, not smoothly self-evident designs of the Invention directed.  

Claim 14 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 passed through a tack driven. With a further movement of the part or all of it through the booklet driven piece of wire in the direction of a counter bearing becomes a bending jaw, which or is rotatably mounted in a movable item support on which the item to be placed rests, moved together with the support towards and against the counter bearing Counter bearing pressed. This forces the bending jaw to pivot. While the swiveling movement acts from the side on the piece of wire driven by the material and bends this piece of wire towards the estate.

According to the invention, an active surface presses against the piece of material to be bent the bending jaw already at the beginning of the bending process and during the bending process in the substantially parallel to the piece of wire. This is particularly important in a critical phase of bending, namely when initiating the bending process, avoided that the tip of the Wire piece presses against the effective surface of the bending jaw. The wear of the bending jaw is thereby reduced compared to the known bending devices. Through the Paralleling the bending jaw is the piece of wire through the effective surface of the bending jaw evenly managed. The bending forces acting on the piece of wire are along the length of the piece of wire distributed applied. Those attacking the tip of the piece of material lateral forces can, because of the use according to the invention, by the Well driven length of the piece of material less than in the known Be bending devices. Forces perpendicular to the tip of the piece of wire, like them occur inevitably with inclined bending jaws and driving in Counteracting wire pieces are completely avoided.

The advantages mentioned are particularly noticeable when one Swiveling and thus an active movement of the bending jaw on the piece of wire only takes place after the piece of wire has been substantially completely driven through the material and thus from the beginning of the bending process to the entire length of the material  driving piece of wire for applying the bending force is available.

According to a particularly preferred embodiment of the invention, the axis of rotation is Bending jaw as close to the point of exit of the piece of wire from the tack as this is constructively possible. This results in cooperation with the fact that the piece of wire before Initiation of the bending completely or essentially completely driven by the material the maximum available length for applying the bending force. Through the There is a bending jaw running parallel to the piece of wire and mounted near the exit point optimal bending with force transmission over the entire free length of the wire piece and minimal relative movement between the piece of wire and the bending jaw and thus caused minimal wear of the active surface of the bending jaw possible. The bending jaw lies continuously until the end of the bending process parallel to the piece of wire, so that this can be optimally invested in the property. If the piece of wire is one conventional staple, the entire staple is additionally affected by the effect of Compression compressed if after the complete bending of the Brace leg of the leg additionally against the opposite Clamp bracket is pressed.

The bending jaw is moved around the counter bearing by moving the material support Swiveled axis of rotation. The counter bearing can simply be a base plate of the Bending device or act as a counter bearing with a sliding guide for the Bending jaw is provided. The bending jaw is particularly preferred during the movement of the Stitched goods support against the base plate on such a sliding guide and moved through Sliding guide swiveled in the desired direction. The bending jaw itself has one suitable counter surface to the sliding guide on the opposite side. Slideway and Counter surface are designed so that the bending jaw slides as gently as possible becomes.

It is also advantageous, for example, to attach a coupling rod to both of the above To pivot the base plate as well as on the bending jaw. Such a rigid coupling rod would rotate about its axis of rotation on the base plate by the movement of the item support  and because of their rigid design, the bending jaw about the axis of rotation in the desired Turn direction.

The item to be handled is preferably against a resilient restoring force on the Counter bearing too movable. This training helps that the invention Device can also be used for smaller staplers, in particular hand staplers, in which a motor-driven provision of the item support and counter bearing would be too expensive.

In order to move the item support towards the counter bearing and thus pivot the Allow bending jaw only when the wire piece is essentially completely through the Stitched goods can be a means of generating the restoring force advantageously have a degressive characteristic. The characteristic is like this in this case adjusted that the restoring force from the almost complete penetration of the The pressure required for staples only increases slightly at most.

It is particularly preferred between the item support and a base plate of the device a locking device arranged to release a movement of the item support in Direction to the counter bearing is only triggered after the wire piece in the has essentially been completely driven through the booklet. As a result of that such a locking device can only be triggered, a defined release can be exactly desired time can be achieved.

Advantageously, a plunger is rigidly attached to an upper part of the bending device or attachable attached, the through the booklet or on the side past the booklet on the locking device acts when the upper part is in a corresponding position in the the piece of wire is driven essentially completely through the item to be stitched, located.

According to a further preferred embodiment of the invention is in the magazine support a bending die arranged with an edge that is driven by the material to be stitched Wire piece supported at its exit point, so that the wire piece as a result of  Pivoting movement of the bending jaw is bent exactly around this edge of the bending die. The bending die is used during the bending process, especially towards the end of the Bending process, moved out of the bending area to the flat pressure of the to allow bent wire piece.

The bending die can be designed in one piece or in several pieces.

With a one-piece design, the bending die tapers along its bending edge in Towards the piece of wire, d. H. towards the bending area. Through the rejuvenation slightly move the bending die out of the bending area. The bending die is preferably straight in the magazine support, but can also be advantageous from the Bending area be pivotally mounted.

If several pieces of wire have to be bent at the same time, for example the two legs a U-shaped staple, the bending die can also be designed in two pieces, wherein each of the die pieces with its bending edge each one of the to be bent Wire pieces or staple legs is assigned. The two die pieces are in In this case, it can advantageously be pivoted relative to one another in the magazine support arranged.

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 apparatus at the start of the bending process in cross-section,

Fig. 2 is a partial section of the bending device according to FIG. 1 during the bending operation,

Fig. 3 is a partial section of FIG. 2 after the bending operation,

Fig. 4 is a bending jaw,

Fig. 5, the bending apparatus according to Fig. 1 in longitudinal section with locking device,

Fig. 6 is a bending device with the bending mold in cross-section,

Fig. 7 shows the bending die of Fig. 6 and

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

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 are each pivoted about a pivot axis 26 which is very near an exit point 5, at which the staple leg 3 abuts through the material to be stitched. 1

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 active surface 23 running vertically 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 faces a bending jaw 20 . Each of the bending jaws 20 has a sliding surface 24 facing its associated guide 34 on the counter bearing 30 , with which it slides on the corresponding guide 34 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 . In particular, the initiation of the sliding movement and thus the pivoting movement of the bending jaw 20 is facilitated. In the exemplary embodiment, the sliding surface 24 of the bending jaw 20 is rounded, in particular rounded in the form of a segment of a circle, while the guide 34 on the thrust bearing 30 extends in a straight line and obliquely.

In FIG. 2 shows the state during and in Fig. 3 at the end of the bending operation. The leg 3 of the staple 2 is completely bent in Fig. 3 and pressed flat against the staple 1 . The bending jaw 20 is located with a direction parallel to its active surface 23 rear surface 25 between the guides 34 on the anvil 30 so that is pressed in this state, the already fully folded staple legs 3 flat against the material to be stitched. 1 A rear surface 28 of the bending jaw 20 facing the opposite-side guide 34 when the clamp leg 3 is bent over, is bevelled so that the bending jaw 20 comes to lie at a certain distance from the guide 34 and thus freely therefrom, and only counter in the vertical direction by the counter-bearing 30 the staple 1 is pressed. An additional pressing after bending the clamp leg 3 to achieve post-compression is possible.

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. The bending jaw 20 is provided on both sides with a circular segment-shaped rail 27 which is slidably guided in a corresponding support-side guide groove. By forming a link guide, the axis of rotation 26 of the bending jaw 20 can be placed anywhere near 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.

In Fig. 5, a hand stapler with a locking device is shown 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 in time, a locking device with a support 14 fastened to the underside of the item support 10 and a rocker arm 44 rotatably attached to the base plate 40 about an axis 47 prevents movement of the item support 10 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 locked position is essentially perpendicular to the item support 10 , and with a second leg 46 which extends approximately parallel to the item support 10 in the locked position. The axis of rotation 47 of the rocker arm 44 lies in the region of the intersection of these two legs and 46 . Furthermore, the rocker arm 44 has an extension 48 on the side of the two legs 45 and 46 facing th side of the rocker arm axis of rotation 47 . 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 presses with the opposite other 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 contact 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 possible in principle, 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 protruding from the release pin 42 and the spring force of the return spring 49 are coordinated so that the pressing force on the release pin 42 weight of the staple 1 and usual vibrations of the stapler can not 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 substantially 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 so that it is now opposite the release pin 42 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.

The pressure of the plunger 52 through the item 1 is sufficient in most applications 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 FIG. 5, a bending device according to the invention can be combined with the upper parts customary for hand stitchers. 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 extends with one end between the two clip legs 3 of the driven therethrough the material to be stitched 1 staple. 2 At this end, the bending die 60 has a trapezoidal cross section. An upper surface of the bending die 60 facing the underside of the item support 10 extends with its acute-angled side edges 61 in each case tightly up to the two clamp legs 3 . From the side edges 61 , the two side surfaces 62 of the bending die 60 facing the clamp legs 3 are chamfered to their narrower surface facing the base plate 40 . 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 FIG. 6 is slidingly guided in a straight manner in the item support 10 , its direction of movement pointing perpendicular to the cutting plane shown, ie parallel to the axes of rotation 26 of the bending jaws 20 .

After the staple leg 3 near their exit points 5 (Fig. 1) have been bent, the bending die is moved by an appropriate mechanism of the bending portion 60 not to hinder the further bending. The movement is coupled in a suitable manner to the movement of the item support 10 . In order to facilitate the outward movement of the bending mold 60 from the bending portion, the bending mold is management of Example 60 from which geradverfährbare bending mold 60 that is tapered along their side edges 61 in the direction of its bending area for oriented end. This is shown more clearly in FIG. 7.

An alternative pivot mechanism for the bending jaws 20 is shown schematically in FIG. 8. 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 .

Claims (14)

1. 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 ) through a side of the wire piece ( 3 ) Acting bending jaw ( 20 ), which is rotatably mounted on a movable object support ( 10 ) and is pressed towards the counter bearing ( 30 ), is bent toward the object to be handled ( 1 ), characterized in that an active surface (facing the piece of wire ( 3 ) to be bent) 23 ) of the bending jaw ( 20 ) at the beginning and during a bending process essentially parallel to the piece of wire ( 3 ). 2. Apparatus 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 ) has been substantially completely ge through the material to be stitched ( 1 ) is. 3. Apparatus according to claim 1 or 2, characterized in that an axis of rotation ( 26 ) of the bending jaw ( 20 ) near the exit point ( 5 ) of the through the stitched material ( 1 ) geared wire piece ( 3 ) is arranged. 4. Device according to one of the preceding claims, characterized in that the bending jaw ( 20 ) during a movement of the item 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 transferred. 5. The device according to claim 4, characterized in that the counter bearing ( 30 ) is provided with a bevelled guide surface ( 34 ) for the bending jaw ( 20 ), on which the bending jaw ( 20 ) slides along during its pivoting movement. 6. Device according to one of the preceding claims, characterized in that the item support ( 10 ) is movable against a resilient restoring force on the counter bearing ( 30 ). 7. The device according to claim 6, characterized in that a means ( 4 ) for generating the restoring force has a degressive characteristic. 8. Device according to one of the preceding claims, characterized in that a locking device ( 14 , 44 ) is arranged between the item support ( 10 ) and a base plate ( 40 ) which for releasing a movement of the item support ( 10 ) in the direction of the counter bearing ( 30 ) is only triggered after the wire piece ( 3 ) has been driven substantially completely through the item to be stitched ( 1 ). 9. The device according to claim 8, characterized in that the triggering of the locking device ( 14 , 44 ) by an arranged on an upper part ( 50 ) of the device plunger ( 52 ) through the staple ( 1 ) or past the staple ( 1 ) he follows. 10. Device according to one of the preceding claims, characterized in that a bending die ( 60 ) is arranged in the item support ( 10 ), which has an edge ( 61 ) with which it drives the piece of wire ( 3 ) driven by the item ( 1 ) supported at the beginning of the bending process, so that it is bent directly at the exit point ( 5 ) and which is moved out of the area of the wire piece ( 3 ) during the bending process, in particular towards the end of the bending process, so that the wire piece ( 3 ) is complete can be bent. 11. The device according to claim 10, characterized in that the bending die ( 60 ) has at its end the wire piece ( 3 ) supporting end ( 63 ) to the wire piece ( 3 ) facing acute-angled side surface ( 62 ). 12. The apparatus of claim 10 or 11, characterized in that the bending die ( 60 ) along its edge ( 61 ) towards it the wire piece ( 3 ) under the supporting end ( 63 ) tapers. 13. Device according to one of claims 10 to 12, characterized in that the bending die ( 60 ) is constructed in several pieces with mutually movable edges ( 61 ) or in one piece with a plurality of edges ( 61 ). 14. Device for bending staples, especially hand stapler, thereby ge indicates that a device for bending wire-like materials after a of the preceding claims is used.