Title of Invention	"A TOOL RING AND A NAIL MACHINE COMPRISING SUCH TOOL RING"
Abstract	The invention provides a nail machine and a tool ring for securing preferably elongate bodies in a nail machine, e.g. for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference and a surface that extends substantially perpendicular to the axis of rotation, and wherein the tool ring further comprises a number of engagement devices intended for receiving and releasably securing bodies, and which are spaced substantially equally apart at the circumference of the tool ring, said engagement devices each comprising two mutually opposed holding jaws; and wherein at least the one of the two holding jaws is/are movable, it being arranged on a movement mechanism so configured that the holding jaw can be displaced towards and away from, respectively, the opposed holding jaw; and wherein the movement mechanism is so arranged that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring. Hereby the productivity obtained with a given machine comprising a tool ring with a given number of tools is increased.

Title of Invention

"A TOOL RING AND A NAIL MACHINE COMPRISING SUCH TOOL RING"

Abstract

The invention provides a nail machine and a tool ring for securing preferably elongate bodies in a nail machine, e.g. for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference and a surface that extends substantially perpendicular to the axis of rotation, and wherein the tool ring further comprises a number of engagement devices intended for receiving and releasably securing bodies, and which are spaced substantially equally apart at the circumference of the tool ring, said engagement devices each comprising two mutually opposed holding jaws; and wherein at least the one of the two holding jaws is/are movable, it being arranged on a movement mechanism so configured that the holding jaw can be displaced towards and away from, respectively, the opposed holding jaw; and wherein the movement mechanism is so arranged that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring. Hereby the productivity obtained with a given machine comprising a tool ring with a given number of tools is increased.

Full Text	A tool ring and a nail machine comprising such tool ring The present invention relates to a tool ring for securing preferably elongate bodies in a machine, eg for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference and a surface extending substantially perpendicular to the axis of rotation; and wherein the tool ring further comprises a number of engagement means arranged for receiving and releasably securing bodies and spaced substantially equally apart at the circumference of the tool ring, said engagement means each comprising two mutually opposed holding jaws, and wherein at least one of the two holding jaws is/are arranged on a movement mechanism which is arranged to enable the holding jaw to be displaced towards and away from, respectively, the opposed holding jaw. Such tool ring is known ia from Danish patent Nos 143 935 and 163 111. The tool ring is used in these machines for the manufacture of nails, wherein the tool ring is ro-tatably suspended about the axis of rotation of the tool ring opposite a wire cutter that serves to cut off elongate wire bodies from a storage of metal wire and shift said elongate bodies onwards for receiving and securing on the tool ring. The tool ring is arranged opposite a second tool ring, the circumference of which corresponds to this tool ring, but it is not provided with engagement means. This second tool ring is also rotatably suspended about an axis of rotation which is substantially coaxial with the axis of rotation of the first tool ring, but having an angulation of a few degrees relative to the axis of rotation of the first tool ring, whereby an elongate body arranged between the tool rings is secured there between in that area where the distance between the tool rings is relatively small, and wherein the elongate body is loosened between the tool rings at the substantially opposite side of the tool rings. In this context, the term 'nail' is used to designate any object having a shaft which is, at its one end, provided with a head. In the area where the elongate body is secured between the two tool rings, the wire body is so well secured that it is possible to forge or roll a head onto the one end of the wire body, and for this purpose the tool rings are, at each engagement means, provided with a plurality of opposed pairs of holding trays made of an extremely wear resistant material and each having a groove for receiving the elongate body. Here the engagement means in the tool ring serves to engage with the elongate body and to secure and position it in such a manner that with a high degree of certainty the body will be correctly positioned in the groove in the holding trays when the holding trays closes in on the elongate body. Thus, the known nail machines function by the tool rings being caused to rotate synchronously about their axes of rotation, whereby the individual pairs of holding trays are successively conveyed past the wire cutter that inserts an elongate body between the tool rings, each of said engagement means engaging with and positioning an elongate body between the two tool rings which subsequently, by their rotation, remove the elongate object and lock it between the tool rings, following which a head is rolled onto the one end of the elongate body, and wherein the tool rings subsequently release the elongate body in the form of a nail or the like. It is a problem with these prior art nail machines to control and synchronise the wire cutter to ensure that the individual elongate bodies are reliably introduced between the holding jaws on each of the engagement means, said holding jaws being arranged in or radially opposite the space between the tool rings. In practice, this means that the speed of rotation of the tool rings is restricted by the need for introducing an elongate body during that period of time when the engagement means are positioned directly opposite the wire cutter, and that the productivity can be increased for a given nail machine only if the number of holding trays with accompanying engagement means is increased. In practice this means that the known tool rings typically contain about 20 to 40 sets of holding trays and accompanying engagement means. In the light of this, it is the object of the present invention to provide a tool ring that allows a higher degree of freedom when it comes to obtaining a desired productivity for a given nail machine without necessarily entailing that a given number of holding trays with accompanying engagement means are required. This is obtained by use of a tool ring as described in the introductory part and characterised in that the movement mechanism for displacing at least the one holding jaw is so configured that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring. As opposed to the known tool rings, and provided the tool ring is rotated such that the displaceable holding jaw of each pair of holding jaws is located opposite the opposed holding jaw in the direction of rotation of the tool ring, this enables the elongate body to be advanced to the tool ring to occupy a position in which the elongate body can be seized by the holding jaws in the engagement device before said engagement means becomes positioned opposite the wire cutter. This means that, at a given speed of rotation for the tool ring, more time is available for introducing the elongate body whereby the above-described limitation imposed on the productivity obtainable with a given tool ring having a given number of holding trays and accompanying engagement means is eliminated or at least considerably reduced. Accordingly, there is provided 'a tool ring' for securing preferably elongate bodies in a machine for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference, and a surface that extend s-ubatantiaily perpendicular to said axis of rotation; and wherein the tool ring further composes a number of engagement devices configured to receive and releasably secure bodies, and are equally spaced apart at the circumference of the tool ring, said engagement devices each comprising two opposed holding jaws, and wherein at least the one of the two holding jaws is/are movable aiuftfi it is, positioned on a movement mechanism which is so configured that the holding jaw can be displaced towards and away from, respectively, the opposed holding jaw, characterized in that said movement mechanism is so configured that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring. According to a particularly preferred embodiment of the invention it is obtained that undesired variations in the positioning of the individual elongate bodies due to play, if any, in the movement mechanisms of the engagement means, are eliminated or at least considerably reduced by one of the holding jaws in the engagement means being immovably secured on the tool ring, and by the tool ring being configured for rotation in such direction that the immovable holding jaw in each engagement means is situated opposite the immovably secured holding jaw. Advantageously the engagement means is arranged for receiving and securing the elongate bodies in such a manner that the elongate bodies extend completely or partially opposite that surface of the tool ring which is arranged substantially perpendicular to the axis of rotation, and substantially radially inwards towards the axis of rotation of the tool ring and wherein the movement mechanism is so configured that it displaces the movable holding jaw completely or partially in a direction which is axial in relation to the axis of rotation of the tool ring. Hereby it is accomplished that the individual elongate bodies can be introduced radially between the tool ring according to the present invention and a second tool ring arranged oppositely as described above with reference to the prior art nail machines. According to a particularly simple and reliable embodiment, each of the movement mechanisms in the tool ring is so configured as to comprise a shaft which is rotatably arranged in the tool ring; and the movable holding jaw is arranged on a lever which is secured to the shaft of the movement mechanism and extends radially therefrom; and a cam follower is also mounted on the rotatable shaft. Hereby a movement mechanism is established that comprises only a rotatable bedding of the movement mechanism whereby a mechanism is provided which is relatively maintenance-free . In case the cam follower is pivotally mounted on the shaft about the axis of rotation of the shaft, and if, between the lever on which the cam follower is arranged and the shaft is mounted, a torsion spring is arranged in such a manner that upon pivoting of the lever with the cam follower, a springy rotation of the shaft results, it is obtained that the movement mechanism can be used without adjustment in connection with elongate bodies having different diameters. Advantageously, a spring may be arranged between the cam follower on the movement mechanism and the tool ring in such a manner that the spring force from said spring constantly aims to influence the cam follower to abut on the cam device and thereby cause the entire movement mechanism to rotate in such a manner that the movable holding jaw is caused to escape the opposite holding jaw in the engagement means. In this context, the torsion spring arranged between the cam follower and the shaft on the movement mechanism is particularly advantageously dimensioned with a spring force that considerably exceeds the spring force of the spring arranged between the tool ring and the shaft on the movement mechanism. This enables very reliable functioning of the movement mechanism which, without switching, operates with elongate bodies having different diameters . According to a preferred embodiment, the tool ring is so configured that the rotatable shaft of the movement mechanism is arranged such that its axis of rotation points substantially radially inwards towards the axis of rotation of the tool ring. Hereby a movement pattern is obtained for the movable holding jaw that ensures that, in its position near the opposed holding jaw, the movable holding jaw moves substantially in a direction perpendicular to the opposed holding jaw. According to a particularly preferred embodiment, the tool ring has such configuration that the immovably secured holding jaw has a substantially planar holding surface that faces in the direction of rotation of the tool ring; and that the movable holding jaw has a substantially planar holding surface that faces essentially towards the immovably secured holding surface. Hereby adequate attachment of the elongate bodies is obtained which ensures that the bodies are correctly positioned. Furthermore, the present invention relates to a nail machine comprising a tool ring according to the preceding, wherein said nail machine is characterised in comprising a drive device for pulling off a metal wire from a storage, a device for stretching and straightening the wire, a cutter for cutting off desired lengths of elongate bodies of said wire, means for introducing the elongate bodies into the tool ring, a roller for rolling heads onto the elongate body, and means for removing and collecting the elongate bodies provided with heads and to convey said elongate bodies away from the nail machine. The invention will now be described in further detail with reference to the drawings, wherein: Figure 1 is a perspective explanatory sketch of a prior art nail machine which is known in principle and provided with a tool ring according to the present invention; Figure 2a is a sketch of a section of one embodiment of a tool ring according to the invention, seen radially from the outside of the tool ring; Figure 2b is a front view sketch of the embodiment shown in Figure 2a of a tool ring according to the invention; Figure 2c is a sketch of the embodiment of the tool ring shown in Figures 2a and 2b, seen from the centre of the tool ring and radially outwards to the side; Figure 3 is a sectional view along the line A-A in Figure 2b; Figure 4a is a sketch illustrating a sectional view of a first alternative embodiment of a tool ring according to the invention, seen radially from the outside of the tool ring; Figure 4b is a sketch illustrating a front view of the embodiment of a tool ring according to the invention shown in Figure 4a, but where the ring has been straightened for space considerations. Figure 4c is a sketch illustrating the embodiment of a tool ring shown in Figures 4a and 4b, seen from the centre of the tool ring and radially outwards to the side. Thus, Figure 1 illustrates a nail machine 1 comprising a stretching station 2, through which an arrangement of drive rollers 4 serves to pull a metal wire 3 from a not shown coil of wire, and wherein the metal wire is hereby straightened and stretched to a substantially completely straight piece of wire. After the drive rollers 4, the metal wire is displaced into a wire cutter consisting of two rotating wire cutters 5, and from the rotating cutters 5 the pieces of wire 6 cut off the wire 3 are displaced into a tool ring 7 that rotates clockwise in the embodiment shown herein. The individual pieces of wire are secured and positioned by a roller 8 intended therefor, whereby the pieces of wire are caused to extend equal distances towards the centre of the ring. At the lowermost area of the tool ring, a roller 9 is arranged that is configured to co-operate with the tool ring 7 for rolling heads onto the individual pieces of wire 6. The wire pieces 6 provided with heads are subsequently advanced in the tool ring and upwards to the uppermost part of the tool ring 7, where the piece of wire provided with head is released from the tool ring and drops down onto a chute 10 that conveys the piece of wire away from the nail machine. The above mentioned tool machine and its functioning are generally known; and the present invention specifically relates to a tool ring that distinguishes itself by increasing the productivity relative to the number of tools arranged in the tool ring compared to the prior art devices. Thus, the following figures illustrate specific embodiments of the invention in the form of tool rings that may, in principle, successfully be used in connection with the machine shown in Figure 1. Thus, Figures 2a, 2b and 2c outline a first embodiment of a tool ring 7 according to the invention, wherein Figure 2a is a sectional view of an embodiment of a tool ring according to the invention, seen radially from the outside of the tool ring. As will appear three identical sets of holding jaws are shown that each comprises a fixed holding jaw lla,llb,llc, respectively, mounted on the tool ring 7 and a second movable holding jaw 12a,12b/12c that may rotate about an axis perpendicular to the plane of the paper. The holding jaw 12a is shown in the position it occupies before the holding jaws lla and 12a are opposite the spot where a piece of wire 6 is inserted towards the tool ring 7. As will appear, in accordance with the present invention the movable holding jaw 12a is, in this position, displaced axially relative to the axis of rotation of the tool ring such that it is drawn down below the plane defined by the surface 13 of the tool ring 7, whereby a cut-off piece of wire 6 can be inserted to the tool ring across the surface 13 on the tool ring 7 soon enough for the movable jaw to be able to pass the piece of wire 6 without touching it. The holding jaws lib and 12b are subsequently shown in a second position, following insertion of a piece of wire 6 to the tool ring 7, and wherein the movable holding jaw 12b has been pivoted such as to press the piece of wire 6 towards the fixed holding jaw lib. Finally, the same position is shown illustrated at the holding jaws lie and 12c. Now Figure 2b illustrates the same positions as shown in Figure 2a, only as front views on the tool ring 7, perpendicular to the surface 13. The arrow A in Figure 2b illustrates the direction of rotation of the tool ring. It will further appear that the holding jaws 12a, 12b and 12c are moved by means of a cam device 14 mounted on the frame of the nail machine and respective cam followers intended for each of the holding jaws 12a, 12b and 12c in the form of a roller 15a,15b,15c. The principle behind the movement mechanism shown will now be described in further detail below with reference to Figure 3. Figure 2c also illustrates the same positions of the holding jaws as seen in Figures 2a and 2b, but seen from the centre of the tool ring 7 and radially outwards. Here the cam device is seen in a lateral view; and it will appear that the cam device has a ramp 16 that brings about the movement that the movable holding jaws perform from the position illustrated at the holding jaw 12a in figure 2a to the position illustrated at the holding jaw 12b. Now, Figure 3 illustrates a preferred embodiment of the movement mechanism of the movable holding jaw 12a,12b and 12c shown in Figures 2a through 2c. A piece of wire 6 is shown which has been introduced between the tool ring 7 according to the present invention, and a second, opposed tool ring 17. In the tool ring 7, a holding tray 18 is arranged which is provided with a groove 19, and in a similar manner a corresponding holding tray 20 with a groove 21 is arranged in the opposed tool ring 17, and the two holding trays 18 and 20 are, during rotation of the tool rings 7,17, squeezed together with great force around the piece of wire 6, this causing the latter to be secured relative to the tool rings 7,17. However, the holding trays are unsuitable for quickly seizing and securing a piece of wire 6, and therefore the use of such tool rings presupposes a further engagement device for seizing and positioning the piece of wire relative to the grooves 19,21 on the holding trays 18,20. The engagement device shown in Figure 3 corresponds to the one shown in Figures 2a through 2C and, and as mentioned in connection with said figures, it features a fixed holding jaw (not shown in Figure 3) and a movable holding jaw 12b arranged on a lever 22 that extends radially outwards from a first extremity of a shaft 23 which is mounted pivotally in the tool ring 7. At the other extremity of the shaft 23, at cam follower is arranged that comprises a cam roller 15c extending on a cam device 14 arranged along the internal periphery of the tool ring 7. Between the cam follower 23 and the tool ring 1, a torsion spring 24 is arranged which is biased so as to constantly aim at keeping the cam follower in abutment on the cam device, and pulling the holding jaw 12c away from its opposed, fixed holding jaw lie. Moreover, the cam follower with the cam roller 15c is arranged to be rotatable on the shaft 23; and between the cam follower and the shaft, a torsion spring is arranged, said torsion spring being biased in such a manner that it seeks to bias the holding jaw 12 towards its opposed holding jaw lie. Thus, a movement mechanism is provided which serves to provide, throughout the major part of its movement range, a rigid transmission of force between the cam follower and the holding jaw; and wherein the torsion spring 24 works alone. However, an impact spring 25 is arranged having a spring constant that substantially exceeds the spring constant of the torsion spring 24; and wherein it is the sole purpose of the impact spring 25 to ensure that the abutment pressure between the holding jaws lie and 12c and the piece of wire 6 is limited, since the cam follower is able to rotate relative to the shaft 23 against the spring force of the impact spring. Now Figures 4a through 4c illustrate an alternative embodiment of the present invention wherein Figure 4a is a front view sketch that illustrates a section of a first alternative embodiment of a tool ring according to the invention seen radially from the outside of the tool ring; and Figure 4b is a sketch that illustrates a front view of the embodiment of a tool ring according to the invention shown in Figure 4a, but wherein the ring has been straightened for space reasons; and Figure 4c is a sketch illustrating the embodiment of a tool ring shown in Figures 4a and 4b, seen from the centre of the tool ring and radially outwards to the side. Thus, Figure 4a illustrates a tool ring 7 with an alternative configuration of the movement mechanism for the holding jaws: The tool ring is arranged to rotate in the direction indicated by the arrow B, and it will appear that this configuration is so arranged that each of the holding jaws of a engagement device is arranged to be movable relative to the tool ring 7. The holding jaw 26 is displaceably arranged in a parallel guide, and the holding jaw 27 is pivotally arranged in a bearing in the tool ring 7. In accordance with the principle behind of the invention, the two holding jaws 26 and 27 can be moved partially axially relative to the axis of rotation of the tool ring, and the movement pattern of the holding jaws 26 and 27 is illustrated by five different positions by means of a toothed wheel 28 arranged in the tool ring 7 and co-operating with a toothed bar arranged on the holding jaw 26, and an annular toothing on the holding jaw 27, whereby both holding jaws 26 and 27 can be moved by means of one and the same toothed wheel. As will appear from Figure 4a, the holding jaw 27 thus moves down below the surface 13 on the tool ring 7 in those positions where the piece of wire 6 is introduced to the tool ring 7, as will appear from Figure 4b. Thereby the piece of wire 6 can, in accordance with the effect of the present invention, be introduced over a relatively protracted period of time without coming into contact with the holding jaw 27. As will appear from Figure 4c, the toothed wheel 28 is activated as a consequence of a cam follower and a cam device being provided on the internal periphery of the tool ring 7 which, in principle, corresponds to the device shown in Figures 2b and 2c. Obviously, the present invention can be exercised in other manners than those shown as preferred embodiments in the drawings and explained above. Thus, the invention is also useful in connection with nail machines equipped with other types of wire cutters, etc. As regards the holding jaws, they may also have a configuration which is different from the ones shown herein, but such that their movement pattern includes at least an axial or radial movement constituent. We Claim:- 1. 'A tool ring' for securing preferably elongate bodies in a machine for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference, and a surface that extend perpendicular to said axis of rotation; and wherein the tool ring having a number of engagement devices configured to receive and releasably secure bodies, and are equally spaced apart at the circumference of the tool ring, said engagement devices each comprising two opposed holding jaws, and wherein at least the one of the two holding jaws is/are movable and is positioned on a movement mechanism which is so configured that the holding jaw can be displaced towards and away from, respectively, the opposed holding jaw, characterized in that said movement mechanism is so configured that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring. 2. A tool ring as claimed in claim 1, wherein one of the holding jaws is immovably secured on the tool ring; and that the tool ring is arranged for rotation in such direction that the movable holding jaw in each engagement device is positioned opposite the immovably secured holding jaw. 3. A tool ring as claimed in claim 1 or 2, wherein the engagement de vice is configured for receiving and securing the elongate bodies in such a manner that the elongate bodies extend completely or partially opposite that surface of the tool ring which is located perpendicular to the axis of rotation and radially inwards towards the axis of rotation of the tool ring; and wherein the movement mechanism is arranged to displace the movable holding jaw completely or partially in a direction which is axial relative to the axis of rotation of the tool ring. 4. A tool ring as claimed in claim 1, 2 or 3, wherein each of the movement mechanisms in the tool ring comprises a shaft which is rotatably arranged in the tool ring; and that the movable holding jaw is arranged on a lever which is secured to the shaft of the movement mechanism and extends radially outwards therefrom; and that the rotatable shaft is further provided with a cam follower. 5. A tool ring as claimed in claim 4, wherein the cam follower is pivotally mounted on the shaft about the axis of rotation of the shaft; and that a torsion spring is mounted between that lever on which the cam follower is arranged and the shaft, in such a manner that, upon pivoting of the lever with the cam follower, a springy rotation of the shaft results. 6. A tool ring as claimed in claim 4 or 5, wherein a spring is arranged between the shaft on the movement mechanism and the tool ring whereby the spring force from said spring constantly aims to influence the movement mechanism to rotate in such a manner that the movable holding jaw seeks to escape the opposed holding jaw in the engagement device. 7. A tool ring as claimed in claim 5 or 6, wherein the torsion spring arranged between the cam follower and the shaft on the movement mechanism is dimensioned with such spring force which substantially exceeds the spring force of the spring arranged between the tool ring and the cam follower on the movement mechanism. 8. A tool ring as claimed in anyone of claims 4 to 7, wherein the rotatable shaft of the movement mechanism is so arranged that its axis of rotation extends substantially radially inwards towards, the axis of rotation of the tool ring. 9. A tool ring as claimed in anyone of the preceding claims 2 to 8, wherein the immovably secured holding jaw has a holding surface that faces in the direction of rotation of the tool ring; and that the movable holding jaw has a holding surface that faces substantially towards the immovably secured holding surface. 10. A nail machine comprising a tool ring as claimed in any one of the preceding claims, wherein it comprises a drive device for pulling a metal wire from a storage; a device for stretching and straightening the wire, a cutter for cutting elongate bodies having a desired length off said wire; means for introducing the elongate bodies to the tool ring; a roller for rolling heads onto the elongate bodies; and means for removing and collecting the elongate bodies provided with heads and for conveying the elongate bodies away from the nail machine. 11. A tool ring substantially as hereinbefore described with reference the accompanying drawings. 12. A nail machine substantially as hereinbefore described with reference the accompanying drawings.

Full Text

A tool ring and a nail machine comprising such tool ring
The present invention relates to a tool ring for securing preferably elongate bodies in a machine, eg for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference and a surface extending substantially perpendicular to the axis of rotation; and wherein the tool ring further comprises a number of engagement means arranged for receiving and releasably securing bodies and spaced substantially equally apart at the circumference of the tool ring, said engagement means each comprising two mutually opposed holding jaws, and wherein at least one of the two holding jaws is/are arranged on a movement mechanism which is arranged to enable the holding jaw to be displaced towards and away from, respectively, the opposed holding jaw.
Such tool ring is known ia from Danish patent Nos 143 935 and 163 111. The tool ring is used in these machines for the manufacture of nails, wherein the tool ring is ro-tatably suspended about the axis of rotation of the tool ring opposite a wire cutter that serves to cut off elongate wire bodies from a storage of metal wire and shift said elongate bodies onwards for receiving and securing on the tool ring. The tool ring is arranged opposite a second tool ring, the circumference of which corresponds to this tool ring, but it is not provided with engagement means. This second tool ring is also rotatably suspended about an axis of rotation which is substantially coaxial with the axis of rotation of the first tool ring, but having an angulation of a few degrees relative to the axis of rotation of the first tool ring, whereby an elongate body arranged between the tool rings is secured there between in that area where the distance between the tool rings is relatively small, and wherein the elongate

body is loosened between the tool rings at the substantially opposite side of the tool rings.
In this context, the term 'nail' is used to designate any object having a shaft which is, at its one end, provided with a head.
In the area where the elongate body is secured between the two tool rings, the wire body is so well secured that it is possible to forge or roll a head onto the one end of the wire body, and for this purpose the tool rings are, at each engagement means, provided with a plurality of opposed pairs of holding trays made of an extremely wear resistant material and each having a groove for receiving the elongate body. Here the engagement means in the tool ring serves to engage with the elongate body and to secure and position it in such a manner that with a high degree of certainty the body will be correctly positioned in the groove in the holding trays when the holding trays closes in on the elongate body.
Thus, the known nail machines function by the tool rings being caused to rotate synchronously about their axes of rotation, whereby the individual pairs of holding trays are successively conveyed past the wire cutter that inserts an elongate body between the tool rings, each of said engagement means engaging with and positioning an elongate body between the two tool rings which subsequently, by their rotation, remove the elongate object and lock it between the tool rings, following which a head is rolled onto the one end of the elongate body, and wherein the tool rings subsequently release the elongate body in the form of a nail or the like.
It is a problem with these prior art nail machines to control and synchronise the wire cutter to ensure that

the individual elongate bodies are reliably introduced between the holding jaws on each of the engagement means, said holding jaws being arranged in or radially opposite the space between the tool rings. In practice, this means that the speed of rotation of the tool rings is restricted by the need for introducing an elongate body during that period of time when the engagement means are positioned directly opposite the wire cutter, and that the productivity can be increased for a given nail machine only if the number of holding trays with accompanying engagement means is increased. In practice this means that the known tool rings typically contain about 20 to 40 sets of holding trays and accompanying engagement means.
In the light of this, it is the object of the present invention to provide a tool ring that allows a higher degree of freedom when it comes to obtaining a desired productivity for a given nail machine without necessarily entailing that a given number of holding trays with accompanying engagement means are required.
This is obtained by use of a tool ring as described in the introductory part and characterised in that the movement mechanism for displacing at least the one holding jaw is so configured that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring. As opposed to the known tool rings, and provided the tool ring is rotated such that the displaceable holding jaw of each pair of holding jaws is located opposite the opposed holding jaw in the direction of rotation of the tool ring, this enables the elongate body to be advanced to the tool ring to occupy a position in which the elongate body can be seized by the holding jaws in the engagement device before said engagement means becomes positioned

opposite the wire cutter. This means that, at a given speed of rotation for the tool ring, more time is available for introducing the elongate body whereby the above-described limitation imposed on the productivity obtainable with a given tool ring having a given number of holding trays and accompanying engagement means is eliminated or at least considerably reduced.
Accordingly, there is provided 'a tool ring' for securing preferably elongate bodies in a machine for the manufacture of heads on said elongate bodies, said tool ring having an axis of rotation, an outer circumference, and a surface that extend s-ubatantiaily perpendicular to said axis of rotation; and wherein the tool ring further composes a number of engagement devices configured to receive and releasably secure bodies, and are equally spaced apart at the circumference of the tool ring, said engagement devices each comprising two opposed holding jaws, and wherein at least the one of the two holding jaws is/are movable aiuftfi it is, positioned on a movement mechanism which is so configured that the holding jaw can be displaced towards and away from, respectively, the opposed holding jaw, characterized in that said movement mechanism is so configured that it displaces the holding jaw completely or partially in a radial or axial direction relative to the axis of rotation of the tool ring.

According to a particularly preferred embodiment of the invention it is obtained that undesired variations in the positioning of the individual elongate bodies due to play, if any, in the movement mechanisms of the engagement means, are eliminated or at least considerably reduced by one of the holding jaws in the engagement means being immovably secured on the tool ring, and by the tool ring being configured for rotation in such direction that the immovable holding jaw in each engagement means is situated opposite the immovably secured holding jaw.
Advantageously the engagement means is arranged for receiving and securing the elongate bodies in such a manner that the elongate bodies extend completely or partially opposite that surface of the tool ring which is arranged substantially perpendicular to the axis of rotation, and substantially radially inwards towards the axis of rotation of the tool ring and wherein the movement mechanism is so configured that it displaces the movable holding jaw completely or partially in a direction which is axial in relation to the axis of rotation of the tool ring. Hereby it is accomplished that the individual elongate bodies can be introduced radially between the tool ring according to the present invention and a second tool ring arranged oppositely as described above with reference to the prior art nail machines.

According to a particularly simple and reliable embodiment, each of the movement mechanisms in the tool ring is so configured as to comprise a shaft which is rotatably arranged in the tool ring; and the movable holding jaw is arranged on a lever which is secured to the shaft of the movement mechanism and extends radially therefrom; and a cam follower is also mounted on the rotatable shaft. Hereby a movement mechanism is established that comprises only a rotatable bedding of the movement mechanism whereby a mechanism is provided which is relatively maintenance-free .
In case the cam follower is pivotally mounted on the shaft about the axis of rotation of the shaft, and if, between the lever on which the cam follower is arranged and the shaft is mounted, a torsion spring is arranged in such a manner that upon pivoting of the lever with the cam follower, a springy rotation of the shaft results, it is obtained that the movement mechanism can be used without adjustment in connection with elongate bodies having different diameters.
Advantageously, a spring may be arranged between the cam follower on the movement mechanism and the tool ring in such a manner that the spring force from said spring constantly aims to influence the cam follower to abut on the cam device and thereby cause the entire movement mechanism to rotate in such a manner that the movable holding jaw is caused to escape the opposite holding jaw in the engagement means.
In this context, the torsion spring arranged between the cam follower and the shaft on the movement mechanism is particularly advantageously dimensioned with a spring force that considerably exceeds the spring force of the spring arranged between the tool ring and the shaft on

the movement mechanism. This enables very reliable functioning of the movement mechanism which, without switching, operates with elongate bodies having different diameters .
According to a preferred embodiment, the tool ring is so configured that the rotatable shaft of the movement mechanism is arranged such that its axis of rotation points substantially radially inwards towards the axis of rotation of the tool ring. Hereby a movement pattern is obtained for the movable holding jaw that ensures that, in its position near the opposed holding jaw, the movable holding jaw moves substantially in a direction perpendicular to the opposed holding jaw.
According to a particularly preferred embodiment, the tool ring has such configuration that the immovably secured holding jaw has a substantially planar holding surface that faces in the direction of rotation of the tool ring; and that the movable holding jaw has a substantially planar holding surface that faces essentially towards the immovably secured holding surface. Hereby adequate attachment of the elongate bodies is obtained which ensures that the bodies are correctly positioned.
Furthermore, the present invention relates to a nail machine comprising a tool ring according to the preceding, wherein said nail machine is characterised in comprising a drive device for pulling off a metal wire from a storage, a device for stretching and straightening the wire, a cutter for cutting off desired lengths of elongate bodies of said wire, means for introducing the elongate bodies into the tool ring, a roller for rolling heads onto the elongate body, and means for removing and collecting the elongate bodies provided with heads and to convey said elongate bodies away from the nail machine.

The invention will now be described in further detail with reference to the drawings, wherein:
Figure 1 is a perspective explanatory sketch of a prior art nail machine which is known in principle and provided with a tool ring according to the present invention;
Figure 2a is a sketch of a section of one embodiment of a tool ring according to the invention, seen radially from the outside of the tool ring;
Figure 2b is a front view sketch of the embodiment shown in Figure 2a of a tool ring according to the invention;
Figure 2c is a sketch of the embodiment of the tool ring shown in Figures 2a and 2b, seen from the centre of the tool ring and radially outwards to the side;
Figure 3 is a sectional view along the line A-A in Figure 2b;
Figure 4a is a sketch illustrating a sectional view of a first alternative embodiment of a tool ring according to the invention, seen radially from the outside of the tool ring;
Figure 4b is a sketch illustrating a front view of the embodiment of a tool ring according to the invention shown in Figure 4a, but where the ring has been straightened for space considerations.
Figure 4c is a sketch illustrating the embodiment of a tool ring shown in Figures 4a and 4b, seen from the centre of the tool ring and radially outwards to the side.

Thus, Figure 1 illustrates a nail machine 1 comprising a stretching station 2, through which an arrangement of drive rollers 4 serves to pull a metal wire 3 from a not shown coil of wire, and wherein the metal wire is hereby straightened and stretched to a substantially completely straight piece of wire. After the drive rollers 4, the metal wire is displaced into a wire cutter consisting of two rotating wire cutters 5, and from the rotating cutters 5 the pieces of wire 6 cut off the wire 3 are displaced into a tool ring 7 that rotates clockwise in the embodiment shown herein. The individual pieces of wire are secured and positioned by a roller 8 intended therefor, whereby the pieces of wire are caused to extend equal distances towards the centre of the ring. At the lowermost area of the tool ring, a roller 9 is arranged that is configured to co-operate with the tool ring 7 for rolling heads onto the individual pieces of wire 6. The wire pieces 6 provided with heads are subsequently advanced in the tool ring and upwards to the uppermost part of the tool ring 7, where the piece of wire provided with head is released from the tool ring and drops down onto a chute 10 that conveys the piece of wire away from the nail machine.
The above mentioned tool machine and its functioning are generally known; and the present invention specifically relates to a tool ring that distinguishes itself by increasing the productivity relative to the number of tools arranged in the tool ring compared to the prior art devices.
Thus, the following figures illustrate specific embodiments of the invention in the form of tool rings that may, in principle, successfully be used in connection with the machine shown in Figure 1.

Thus, Figures 2a, 2b and 2c outline a first embodiment of a tool ring 7 according to the invention, wherein Figure 2a is a sectional view of an embodiment of a tool ring according to the invention, seen radially from the outside of the tool ring. As will appear three identical sets of holding jaws are shown that each comprises a fixed holding jaw lla,llb,llc, respectively, mounted on the tool ring 7 and a second movable holding jaw 12a,12b/12c that may rotate about an axis perpendicular to the plane of the paper. The holding jaw 12a is shown in the position it occupies before the holding jaws lla and 12a are opposite the spot where a piece of wire 6 is inserted towards the tool ring 7. As will appear, in accordance with the present invention the movable holding jaw 12a is, in this position, displaced axially relative to the axis of rotation of the tool ring such that it is drawn down below the plane defined by the surface 13 of the tool ring 7, whereby a cut-off piece of wire 6 can be inserted to the tool ring across the surface 13 on the tool ring 7 soon enough for the movable jaw to be able to pass the piece of wire 6 without touching it.
The holding jaws lib and 12b are subsequently shown in a second position, following insertion of a piece of wire 6 to the tool ring 7, and wherein the movable holding jaw 12b has been pivoted such as to press the piece of wire 6 towards the fixed holding jaw lib. Finally, the same position is shown illustrated at the holding jaws lie and 12c.
Now Figure 2b illustrates the same positions as shown in Figure 2a, only as front views on the tool ring 7, perpendicular to the surface 13. The arrow A in Figure 2b illustrates the direction of rotation of the tool ring. It will further appear that the holding jaws 12a, 12b and 12c are moved by means of a cam device 14 mounted on the

frame of the nail machine and respective cam followers intended for each of the holding jaws 12a, 12b and 12c in the form of a roller 15a,15b,15c. The principle behind the movement mechanism shown will now be described in further detail below with reference to Figure 3.
Figure 2c also illustrates the same positions of the holding jaws as seen in Figures 2a and 2b, but seen from the centre of the tool ring 7 and radially outwards. Here the cam device is seen in a lateral view; and it will appear that the cam device has a ramp 16 that brings about the movement that the movable holding jaws perform from the position illustrated at the holding jaw 12a in figure 2a to the position illustrated at the holding jaw 12b.
Now, Figure 3 illustrates a preferred embodiment of the movement mechanism of the movable holding jaw 12a,12b and 12c shown in Figures 2a through 2c. A piece of wire 6 is shown which has been introduced between the tool ring 7 according to the present invention, and a second, opposed tool ring 17. In the tool ring 7, a holding tray 18 is arranged which is provided with a groove 19, and in a similar manner a corresponding holding tray 20 with a groove 21 is arranged in the opposed tool ring 17, and the two holding trays 18 and 20 are, during rotation of the tool rings 7,17, squeezed together with great force around the piece of wire 6, this causing the latter to be secured relative to the tool rings 7,17. However, the holding trays are unsuitable for quickly seizing and securing a piece of wire 6, and therefore the use of such tool rings presupposes a further engagement device for seizing and positioning the piece of wire relative to the grooves 19,21 on the holding trays 18,20. The engagement device shown in Figure 3 corresponds to the one shown in Figures 2a through 2C and, and as mentioned in connection with said figures, it features a fixed holding jaw (not

shown in Figure 3) and a movable holding jaw 12b arranged on a lever 22 that extends radially outwards from a first extremity of a shaft 23 which is mounted pivotally in the tool ring 7.
At the other extremity of the shaft 23, at cam follower is arranged that comprises a cam roller 15c extending on a cam device 14 arranged along the internal periphery of the tool ring 7. Between the cam follower 23 and the tool ring 1, a torsion spring 24 is arranged which is biased so as to constantly aim at keeping the cam follower in abutment on the cam device, and pulling the holding jaw 12c away from its opposed, fixed holding jaw lie. Moreover, the cam follower with the cam roller 15c is arranged to be rotatable on the shaft 23; and between the cam follower and the shaft, a torsion spring is arranged, said torsion spring being biased in such a manner that it seeks to bias the holding jaw 12 towards its opposed holding jaw lie.
Thus, a movement mechanism is provided which serves to provide, throughout the major part of its movement range, a rigid transmission of force between the cam follower and the holding jaw; and wherein the torsion spring 24 works alone. However, an impact spring 25 is arranged having a spring constant that substantially exceeds the spring constant of the torsion spring 24; and wherein it is the sole purpose of the impact spring 25 to ensure that the abutment pressure between the holding jaws lie and 12c and the piece of wire 6 is limited, since the cam follower is able to rotate relative to the shaft 23 against the spring force of the impact spring.
Now Figures 4a through 4c illustrate an alternative embodiment of the present invention wherein Figure 4a is a front view sketch that illustrates a section of a first

alternative embodiment of a tool ring according to the invention seen radially from the outside of the tool ring; and Figure 4b is a sketch that illustrates a front view of the embodiment of a tool ring according to the invention shown in Figure 4a, but wherein the ring has been straightened for space reasons; and Figure 4c is a sketch illustrating the embodiment of a tool ring shown in Figures 4a and 4b, seen from the centre of the tool ring and radially outwards to the side.
Thus, Figure 4a illustrates a tool ring 7 with an alternative configuration of the movement mechanism for the holding jaws: The tool ring is arranged to rotate in the direction indicated by the arrow B, and it will appear that this configuration is so arranged that each of the holding jaws of a engagement device is arranged to be movable relative to the tool ring 7. The holding jaw 26 is displaceably arranged in a parallel guide, and the holding jaw 27 is pivotally arranged in a bearing in the tool ring 7. In accordance with the principle behind of the invention, the two holding jaws 26 and 27 can be moved partially axially relative to the axis of rotation of the tool ring, and the movement pattern of the holding jaws 26 and 27 is illustrated by five different positions by means of a toothed wheel 28 arranged in the tool ring 7 and co-operating with a toothed bar arranged on the holding jaw 26, and an annular toothing on the holding jaw 27, whereby both holding jaws 26 and 27 can be moved by means of one and the same toothed wheel.
As will appear from Figure 4a, the holding jaw 27 thus moves down below the surface 13 on the tool ring 7 in those positions where the piece of wire 6 is introduced to the tool ring 7, as will appear from Figure 4b. Thereby the piece of wire 6 can, in accordance with the effect of the present invention, be introduced over a

relatively protracted period of time without coming into contact with the holding jaw 27.
As will appear from Figure 4c, the toothed wheel 28 is activated as a consequence of a cam follower and a cam device being provided on the internal periphery of the tool ring 7 which, in principle, corresponds to the device shown in Figures 2b and 2c.
Obviously, the present invention can be exercised in other manners than those shown as preferred embodiments in the drawings and explained above. Thus, the invention is also useful in connection with nail machines equipped with other types of wire cutters, etc. As regards the holding jaws, they may also have a configuration which is different from the ones shown herein, but such that their movement pattern includes at least an axial or radial movement constituent.

We Claim:-
1. 'A tool ring' for securing preferably elongate bodies in a machine
for the manufacture of heads on said elongate bodies, said tool ring
having an axis of rotation, an outer circumference, and a surface that
extend perpendicular to said axis of rotation; and wherein the tool ring
having a number of engagement devices configured to receive and
releasably secure bodies, and are equally spaced apart at the
circumference of the tool ring, said engagement devices each comprising
two opposed holding jaws, and wherein at least the one of the two
holding jaws is/are movable and is positioned on a movement
mechanism which is so configured that the holding jaw can be displaced
towards and away from, respectively, the opposed holding jaw,
characterized in that said movement mechanism is so configured that it
displaces the holding jaw completely or partially in a radial or axial
direction relative to the axis of rotation of the tool ring.
2. A tool ring as claimed in claim 1, wherein one of the holding jaws
is immovably secured on the tool ring; and that the tool ring is arranged
for rotation in such direction that the movable holding jaw in each
engagement device is positioned opposite the immovably secured holding
jaw.
3. A tool ring as claimed in claim 1 or 2, wherein the engagement de
vice is configured for receiving and securing the elongate bodies in such
a manner that the elongate bodies extend completely or partially opposite
that surface of the tool ring which is located perpendicular to the axis of
rotation and radially inwards towards the axis of rotation of the tool ring;
and wherein the movement mechanism is arranged to displace the
movable holding jaw completely or partially in a direction which is axial
relative to the axis of rotation of the tool ring.
4. A tool ring as claimed in claim 1, 2 or 3, wherein each of the
movement mechanisms in the tool ring comprises a shaft which is
rotatably arranged in the tool ring; and that the movable holding jaw is
arranged on a lever which is secured to the shaft of the movement
mechanism and extends radially outwards therefrom; and that the
rotatable shaft is further provided with a cam follower.
5. A tool ring as claimed in claim 4, wherein the cam follower is
pivotally mounted on the shaft about the axis of rotation of the shaft;
and that a torsion spring is mounted between that lever on which the
cam follower is arranged and the shaft, in such a manner that, upon
pivoting of the lever with the cam follower, a springy rotation of the shaft
results.
6. A tool ring as claimed in claim 4 or 5, wherein a spring is arranged
between the shaft on the movement mechanism and the tool ring
whereby the spring force from said spring constantly aims to influence
the movement mechanism to rotate in such a manner that the movable
holding jaw seeks to escape the opposed holding jaw in the engagement
device.
7. A tool ring as claimed in claim 5 or 6, wherein the torsion spring
arranged between the cam follower and the shaft on the movement
mechanism is dimensioned with such spring force which substantially
exceeds the spring force of the spring arranged between the tool ring and
the cam follower on the movement mechanism.
8. A tool ring as claimed in anyone of claims 4 to 7, wherein the
rotatable shaft of the movement mechanism is so arranged that its axis
of rotation extends substantially radially inwards towards, the axis of
rotation of the tool ring.
9. A tool ring as claimed in anyone of the preceding claims 2 to 8,
wherein the immovably secured holding jaw has a holding surface that
faces in the direction of rotation of the tool ring; and that the movable
holding jaw has a holding surface that faces substantially towards the
immovably secured holding surface.
10. A nail machine comprising a tool ring as claimed in any one of the
preceding claims, wherein it comprises a drive device for pulling a metal
wire from a storage; a device for stretching and straightening the wire, a
cutter for cutting elongate bodies having a desired length off said wire;
means for introducing the elongate bodies to the tool ring; a roller for
rolling heads onto the elongate bodies; and means for removing and
collecting the elongate bodies provided with heads and for conveying the
elongate bodies away from the nail machine.
11. A tool ring substantially as hereinbefore described with reference
the accompanying drawings.
12. A nail machine substantially as hereinbefore described with
reference the accompanying drawings.

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Patent Number

215348

Indian Patent Application Number

1731/DEL/1998

PG Journal Number

11/2008

Publication Date

14-Mar-2008

Grant Date

26-Feb-2008

Date of Filing

22-Jun-1998

Name of Patentee

ENKOTEC A/S

Applicant Address

SVERIGESVEZ 26, DK-8660, SKANDERBORG, DENMARK

Inventors:

#	Inventor's Name	Inventor's Address
1	JENSEN, JORN BOIE	KANALVEJ 3, DL-8400 EBELTOFT, DENMARK

PCT International Classification Number

B21G 3/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	0481/98	1998-04-03	Denmark