Method for the production of a strip for fastening elements

Disclosed is a method for producing a strip for fastening elements, said strip comprising a plurality of interconnected holders, each of which accommodates a shaft of a fastening element. The holders define a fastening direction in which the fastening element can be driven from the holder into a support by a fastening device. The disclosed method comprises the following steps: a) producing a continuous strip defining a longitudinal direction of the strip; b) making the holders from the strip material by means of a deep-drawing process; c) accommodating the fastening elements in the holders.

FIELD OF THE INVENTION

The invention concerns a method for the production of a strip for fastening elements with a plurality of interconnected holding sections for the temporary holding of a fastening element.

BACKGROUND OF THE INVENTION

With such strips, the holding sections usually comprise a holder for a shaft or a head of the pertinent fastening element. During the driving of the fastening element into a support with the aid of a fastening device, the fastening element is pressed from the holder or through the holder, wherein a certain force is to be expended. If necessary, the holder is thereby destroyed, wherein, under certain circumstances, remains of the holder adhere to the fastening element.

For the production of such strips, a method is known for deforming a continuous strip in the later fastening direction in such a way that a holder is formed, into which the fastening element is likewise introduced in the fastening direction.

SUMMARY OF THE INVENTION

It is a goal of the invention to make available a method with which a strip for fastening elements can be produced quickly and favorably.

This goal is attained by a method for the production of a strip for fastening elements with a plurality of interconnected holders for a shaft of a fastening element, wherein the holders define a fastening direction, in which the fastening element can be driven by a fastening device from the holder into a support, wherein the method comprises the following steps:a) production of a continuous strip, which defines a longitudinal direction of the stripb) production of the holders from the material of the stripc) incorporation of the fastening elements into the holders.
wherein during step b, the holders are produced, by a deep-drawing process, transverse to the fastening direction. During the deep-drawing, therefore, a part of the strip material is drawn in a direction other than the fastening direction. The deep-drawing direction is thereby the direction in which the deep-drawing punch is moved, relative to the deep-drawing die. Preferably, the deep-drawing direction is perpendicular to the fastening direction. With particular preference, the deep-drawing direction is perpendicular to the longitudinal direction of the strip. By stretching the deep-drawn material, a material thickness of the holders can be selected independently of a material thickness of the continuous strip.

A preferred embodiment of the method is characterized in that during step b), the strip material that forms a holder leaves an opening in the strip. In accordance with a particularly preferred embodiment, a hole is produced in a longitudinal direction of the strip at the same level with a holder. In a likewise particularly preferred embodiment, a holder is produced between two openings in a longitudinal direction of the strip.

A preferred embodiment of the method is characterized in that the fastening element has a shaft, wherein during step c), the shaft is held in the holder. With particular preference, the fastening element also comprises a tip or a head. The fastening element is preferably provided with a thread and designed as a screw. In alternative embodiments, the fastening element is designed as a nail, bolt, or the like.

A preferred embodiment of the method is characterized in that during or after step b), the holders are provided with a slit. The slit preferably extends along the fastening direction. With particular preference, the slit is designed continuously on the holder. A preferred embodiment of the method is characterized in that during step c), the fastening elements are snapped into the holders. This is preferably carried out through the slit that may be present. With preferred alternative embodiments, the slit extends only over a part of the holder and is not formed continuously.

A preferred embodiment of the method is characterized in that during step c), the fastening elements are introduced into the holders in the fastening direction. With particular preference, the fastening elements are inserted into the holders.

A preferred embodiment of the method is characterized in that during or after step b), the holders are provided with a predetermined breaking point. Preferably, the predetermined breaking point extends along the fastening direction.

A preferred embodiment of the method is characterized in that the fastening element has a head on the end of the shaft, contrary to the fastening direction, and a funnel-shaped expansion section between the head and the shaft; its outside dimensions, transverse to the fastening direction, exceed the inside dimensions of the holder. With particular preference, the funnel-shaped expansion section is designed conically. Preferably, the holder can be expanded through the head or the expansion section—with particular preference, can be bent open—with a movement of the fastening element in the fastening direction.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows an inclined view of a strip100for non-depicted fastening elements with a shaft and a head. The strip100is made of plastic and comprises a multiplicity of interconnected holders120for the temporary holding of a fastening element and connecting sections115, situated between two holders. The fastening elements are thereby preferably held in a middle position, that is, with their center of gravity within a holder120. In non-depicted embodiment examples, the strip is made of a metal foil or a paper strip.

Each holder120is provided for one shaft of a fastening element, which can be driven, in a fastening direction130, from the holder120into a non-depicted support. The fastening direction130is thereby oriented perpendicular to a longitudinal direction170of the strip. The fastening element then bends open the holder120, as a result of its movement, in the fastening direction130and, with a relatively low expenditure of force, snaps out of the holder120. For this purpose, the fastening element has a head on the end of the shaft, contrary to the fastening direction, and a funnel-shaped expansion section between the head and the shaft; the outside dimensions of the expansion section, transverse to the fastening direction, exceed the inside dimensions of the holder.

The holder120has a slit160, which extends continuously over the entire length of the holder120, along the fastening direction130, and a head-side front opening140and a tip-side front opening150of the holder120interconnect. The width of the slit160is smaller than a width of the holder120, so that the non-depicted fastening element can be snapped through the slit160into the holder120and is held securely in the holder120.

The holders120project, in a manner vertical to a strip plane, spanned by the fastening direction130and the longitudinal direction of the strip170, from a continuous core of the strip100. In this way, it is possible, in a simple manner, to form the strip100, with a suitable selection and strength of the material, sufficiently rigid to guarantee a simple conducting of the strip100into a fastening device, without thereby dispensing with the flexibility of the holders120, required for the separation of the fastening elements, which holders have a smaller material thickness than the core of the strip100.

For the production of the strip100, a continuous strip is first produced and from its material, the holders120are then produced. For each holder, subsequently, a rectangular region is drawn out from the continuous strip and against a counter-die, by means of a punch, perpendicular to the fastening direction130and perpendicular to the longitudinal direction170of the strip. The front openings140,150are produced by a prior or simultaneous punching, for example, by correspondingly sharp edges of the punch. The rectangular region is formed, during the deep-drawing or thermoforming, to make up the support walls180,190of the individual holder120. The slit160is produced by a simultaneous or subsequent punching, for example, by a correspondingly sharp, front edge of the punch. The supporting walls180and190thereby leave behind an opening200in the strip100, which is situated in the longitudinal direction of the strip170at the same level with the holder120, since the supporting walls180and190of an opening200are designed bent toward one another and thus jointly form a holder120.

FIG. 2shows a side view of another strip100for non-depicted fastening elements with a shaft and a head. In contrast to the strip shown inFIG. 1, the fastening direction130and longitudinal direction of the strip are not vertical here, but rather oriented inclined to one another at an acute angle. The angle of inclination is, thereby, preferably between 45° and 80°, with particular preference 70°. Due to the arrangement of the fastening elements, which are thus in a staggered connection, their heads partially overlap, so that with the same length of the strip100, more fastening elements are held on the strip.

FIG. 3shows the strip100fromFIG. 1 or 2, in a view in the fastening direction. The same reference symbols thereby stand for the same elements. In addition, a screw110is shown in cross section as the exemplary fastening element, which is held in one of the holders120.

FIG. 4shows a strip400in a cross-sectional view in the fastening direction, with a fastening element410that is held in a holder420. In the production of the strip400, supporting walls480,490are produced by means of a punch; they leave behind an opening499in the strip400. The supporting walls of the opening499are designed bent away from one another in such a way that the supporting wall490of the opening499forms, with a supporting wall480′ of an adjacent opening499′, the holder420, wherein the holder has a continuous slit460in the fastening direction between the supporting walls480,490. In a longitudinal direction470of the strip400, then, a holder420is situated between the openings499,499′.

FIG. 5shows a strip500in a cross-sectional view, in the fastening direction, with a fastening element510that is held in a holder520. In the production of the strip500, the holders520are not slit; rather, one single supporting wall forming the holder520is produced by means of a punch, leaving behind an opening599. The material for the holder is thereby drawn by means of the punch against a counter-die. The counter-die has a pointed edge for the production of a notch525, which is preferably continuous in the fastening direction, which represents a predetermined breaking point, so as to facilitate the separation of the fastening element510.

In non-depicted embodiment examples, the punch alternatively or additionally has a pointed edge, so that the predetermined breaking point is optionally formed by a notch on the outside of the holder, by a notch on the inside of the holder, or by a two-sided weakness of the material of the holder. With other non-depicted embodiment examples, the holders are provided, as an alternative to or in addition to a slit, with a predetermined breaking point.

FIG. 6shows an inclined view of a strip600for non-depicted fastening elements. The strip600comprises a multiplicity of interconnected holders620for the temporary holding of a fastening element and connecting sections615situated between two holders620. The fastening elements are preferably held in the middle, that is, with their center of gravity within a holder620.

Each holder620is provided for a shaft of a fastening element, which can be driven, in a fastening direction630, from the holder620into a non-depicted support. The fastening direction630is inclined, relative to a longitudinal direction670of the strip.

The holder620has a slit660, which extends, proceeding from a head-side front opening640, over a part of the holder620, along the fastening direction630and ends before a tip-side front opening650of the holder120. The end665of the slit660is thereby made to be pointed, so that the fastening element first bends open the holder620as a result of its movement in the fastening direction630, and then tears it open, proceeding from the end665, which is possible as a result of the notch effect, with a relative low expenditure of force.

FIG. 7shows several alternatives of a slit760on a holder720, wherein the alternatives differ mainly in the form of the end765of the slit760. The form of the slit end765is pointed (FIG. 7a), planar (FIG. 7b), or rounded (FIG. 7c). In other embodiment forms, the slit760is not connected with any of the front openings of the holder720, but rather has two ends765,766, which are planar (FIG. 7d), rounded (FIG. 7e), or pointed (FIG. 70. The slit760, in particular its end765, serves under certain circumstances as the theoretical rupture site during the separation of a fastening element from the holder720. In non-depicted embodiment examples, different forms of the two ends of a slit are combined with one another and/or the holder has several slits, for example, a slit in accordance withFIG. 7aand a slit in accordance withFIG. 7f.

In other non-depicted embodiment examples, the holder is provided with a predetermined breaking point in the form of an inside and/or outside notch, for example, as shown inFIG. 5, and with one or more slits, for example, as shown inFIGS. 7aand 7f. Preferably, the notch is thereby designed as a prolongation of the slit beyond its end and, with particular preference, extends to the tip-side front opening of the holder.

The invention under consideration was depicted as an example of a production method for a strip for fastening elements with a shaft and a head in particular, for a fastening device. It should be pointed out, however, that the method in accordance with the invention and the strip in accordance with the invention are also suitable for other application purposes.