AT392028B - NAIL BLOWERS - Google Patents

Description

AT 392 028 B

The invention relates to a nail beating jaw for machines for nail production, consisting of an elongated, prismatic base body with a trapezoidal cross section, which has at one end one or more clamping grooves arranged symmetrically to the cross section, each of which merges into a semi-conical recess, the clamping grooves being in one in one Recess of the base body arranged insert are incorporated.

Such nailing jaws are used in pairs in machines where wire is formed into nails. They are arranged in such a way that the clamping grooves face each other. In the course of the workflow, the nailing jaws are closed or opened. In the closed state, the inserted wire is clamped by the tensioning grooves. The semi-conical recess adjoining the tensioning groove serves for better feeding of the wire. In the clamped state, the nail head is then pressed up and the nail is then cut off. For better clamping of the wire, the clamping groove is profiled, for example, with semicircular transverse grooves

A distinction is made between single-core or two-core nailing jaws, where either one or two adjacent grooves are incorporated. The two-wire design enables the simultaneous production of two nails, i.e. a doubling of the production output.

Such nail hammer jaws are largely made of steel. However, due to the non-optimal wear resistance of steel, they have a limited service life. If the wear of the clamping grooves is inadmissibly high, the nail hammer jaws must be replaced.

In order to increase the wear resistance of the nail hammer jaws, the area of the tool into which the clamping groove is incorporated is made of more wear-resistant material, e.g. B. hard metal. For this purpose, the wear-resistant insert is soldered into a breaking recess in the tool. The costs of such a tool are considerably higher compared to a nail hammer jaw made entirely of steel due to a very complex manufacturing process. The service life of such a hard-tipped nail hammer jaw is at best about five times as long as that of a steel nail hammer jaw. In many cases, however, there may be a premature failure of a hard metal-tipped nail hammer jaw due to cracks due to the soldering stress in the soldered connection. Even if only one nailing jaw fails prematurely, in practice both nailing jaws are exchanged, since the nailing jaws are always manufactured in pairs and when replacing a single nailing jaw the ever increasing demands on the accuracy of the nails cannot be met.

Due to this often quite unfavorable price / performance ratio, such hard-tipped nail hammer jaws have not become widely accepted.

DD-PS 40 525 describes a nail beating jaw made of an elongated, prism-shaped base body with a trapezoidal cross-section with a recess at one end into which a hexagonal insert can be implemented and replaced. The clamping grooves are incorporated into the lateral surfaces of the hexagonal insert. The insert is only fixed in the base body by means of a sheet metal fastened with screws.This means that the insert is only insufficiently fastened in the base body and it comes in particular to movable nailing jaws that work at a frequency of about 1000 strokes / min with the smallest play in the holder Destruction of the edition for use.

The invention has for its object to provide a nail hammer for machines for nail production, which has a convertible and replaceable cutting insert and in which a significantly improved clamping of the insert in the base body is ensured compared to known designs.

According to the invention this is achieved in that the base body in the longitudinal direction for clamping the insert has a slot penetrating the recess for the insert but not the semi-conical recess, so that two resilient sections are formed which can be clamped against one another by a clamping screw.

In this way it is achieved that the insert can be clamped in the base body without play and nevertheless a quick transfer and replacement of the insert is ensured. The special clamping also ensures trouble-free wire entry and thus continuous production.

In a particularly advantageous embodiment of the invention, the insert is made of hard metal and is cubic or cuboid with a vertically running tensioning groove in each lateral surface. In this way, a fourfold use of the carbide insert is made possible with inexpensive production and good clamping.

In another advantageous embodiment, the insert is cube-shaped, each with a vertically running clamping groove in two adjoining lateral surfaces and with a horizontally running clamping groove in a further lateral surface. In this way, the notch effect is reduced and such an insert is particularly suitable for heavy loads in nail production

In a further special embodiment of the invention, the clamping slot runs parallel to a side surface of the base body. In this way it is achieved that the slot runs outside the semi-conical wire feed and still ensures good clamping of the hard metal insert. The invention is explained in more detail below with reference to figures.

It shows: -2-

Claims (5)

AT 392 028 B FIG. 1 a nail hammer jaw according to the invention in perspective view FIG. 2 the hard metal insert for the nail hammer jaw according to FIG. 1, enlarged in perspective view FIG. 3 a variant of the hard metal insert according to FIG. 2 for heavy loads FIG. 1 shows a nail hammer jaw according to the invention, Consisting of an elongated, prism-shaped body (1) made of steel. The side surfaces of the basic holder are each inclined by 15 ° to one another, so that the basic body has a trapezoidal cross section. At its front end, the basic body (1) has a recess for receiving a cube-shaped insert (2) made of hard metal. The recess is designed so that the insert (2) on the front and top surface of the base body (1) protrudes slightly. On the front side of the insert (2) you can see the vertical clamping groove (5) with a semicircular cross-section for clamping the wire. Below the insert (2) in the base body (1) on the face side, a downwardly widening semi-conical recess (6) for wire feed is worked in, which opens into the tensioning groove (5) of the insert (2). To clamp the insert (2), the base body (1) has in the longitudinal direction a slot (3) which begins at the end and passes through the recess for the insert (2), so that two resilient sections of the base body (1) are formed by a Clamping screw (4) can be clamped against the insert (2). The slot (3) runs eccentrically parallel to a side surface of the base body (1) so that it does not penetrate the semi-conical recess (6) for the wire inlet. This ensures problem-free wire feed. The clamping screw (4) is arranged perpendicular to the slot (3). FIG. 2 shows the hard metal insert for the nail beating jaw according to FIG. 1 in an enlarged view. A vertically running clamping groove (5) with a semicircular cross-section is worked into the middle of each lateral surface. For better clamping of the wire, the clamping grooves are provided with a cross profile. In this way, the insert (2) can be used four times. FIG. 3 shows a further variant of a cutting insert (2) for the nail beating jaw according to FIG. 1. In this variant, the insert on two adjoining lateral surfaces each has a centrally arranged, vertically extending clamping groove (5), while a further lateral surface with a centrally arranged, horizontally running clamping groove (5) is provided. Under certain circumstances, the fourth lateral surface can also be provided with a horizontally running clamping groove (5). By designing an insert (2) according to FIG. 3, the notch effect that occurs during processing is reduced, so that such a design is advantageous, particularly under heavy loads. The drawings relate to particularly advantageous embodiments of the invention. However, the invention is in no way limited to these statements. In particular, the shape of the insert (2) is in no way limited to cube-shaped designs. Prisms with a triangular base and blunted corners or with polygonal, z. B. hexagonal base are also suitable as insert (2). PATENT CLAIMS 1. Nail beating jaws for machines for nail production, consisting of an elongated, prism-shaped base body with a trapezoidal cross-section, which at one end has one or more clamping grooves arranged symmetrically to the cross-section, each of which merges into a semi-conical recess, with the clamping grooves in one in a recess of the base body arranged insert are incorporated, the insert being interchangeable and interchangeable clamped in the base body, characterized in that the base body (1) for clamping the insert (2) in the longitudinal direction has a recess for the insert (2), but not the semi-conical one Has recess (6) penetrating slot (3) so that two resilient sections are formed, which can be clamped against each other by a clamping screw (4). 2. nailing jaws according to claim 1, characterized in that the insert (2) consists of hard metal. 3. nailing jaws according to claim 1 or 2, characterized in that the insert (2) is cubic or cuboid with a vertically extending clamping groove (5) in each lateral surface. 4. nailing jaws according to claim 1 or 2, characterized in that the insert (2) is designed cube-shaped, each with a vertically extending clamping groove (5) in two adjacent lateral surfaces and with a horizontally extending clamping groove (5) in a further lateral surface -3- 5 AT 392 028 B 5. nailing jaws according to one of claims 1 to 4, characterized in that the clamping slot (3) runs parallel to a side surface of the base body (1). Add 1 sheet of drawing -4-