Universal clamp for the reproduction of flat keys.

The present invention relates to a vise for subjecting a variety of wrenches as well as its use to create or copy of their teeth bit.

At present, the flat key models placed on the market are becoming more numerous. Their bitting admit various forms sections: simple rectangle flattened with a tapered edge, cross or tee, cylinder or broken lines .... To secure them properly to a fixed support for their machining, it is appropriate to dispose of vice whose jaws are adjusted to the different forms. Often standard clamps are used which one or more pieces are added to make them compatible with the key to work.

Or, moreover, are developing small stalls offering to copy keys in a very short time. For them, the use of conventional clamps are several disadvantages associated with these additional mountings. It must indeed have the stranglehold on every key type of change. Where a waste of time even more important that key provided by each client are varied. Also because of this diversity of models, many adaptation parts are manipulated, which increases the risk of misplacing them, or at least the time required for their choice.

To overcome the lack of convenience traditional vices, the present invention provides a universal clamp for flat keys with a lower plate and an upper plate, the peripheral portion of the bases next working the way jaws to clamp a longitudinal portion of a flat key bit while leaving available the other longitudinal part of the blade, characterized in that said facing bases are hexagonal and in that the form of said jaws is different on each face of the hexagon, each of said forms of said jaws being compatible with the section of a type of key bit particularly flat.

On one of said faces of the hexagon, said jaw consists for example by a vertical flange below said upper plate and a horizontal extension of said bottom plate and fits a key bit of which the clamped longitudinal portion is of rectangular section. On another face, said jaw can also be consitituée by a vertical tip below said upper platform and a notch on said lower platform and fits a key bit section in broken lines. On still another side, said jaw is optionally constituted by a vertical flange below said upper platform comprising a first notch and a second notch identical to the first on said lower plate and fits a key bit section T, the first and the second notches each hosting a branch of the T bar on a last side, said jaw is optionally constituted by a vertical flange below said upper tray whose base admits a profile arcuate recess and arcuate on the lower plate and s'sdapte a cylindrical key bit.

Advantageously, a cylindrical shaft passes through from one side to said upper plate and said lower plate, said shaft being made integral at one of its ends of said lower plate by means of a key and at the other of its ends, it screws into a handle head, a turntable secured to said top plate surrounding said shaft between said handle and said head upper plate and a return spring being placed around said shaft between said turntable and said tray lower within the recess of the upper plate which receives said shaft, means being furthermore provided to prevent rotation of the upper plate about the shaft. It is then preferable that said turntable comprises a sleeve occupying a portion of said upper plate of the recess which receives said shaft and against which said return spring bears, said sleeve being returned by force in said top plate.

According to an advantageous use of this universal clamp, two clamps are secured on a movable plate, one of the clamps carrying a blank and the other a model key of key bits having identical sections, a feeler detecting the shape from the teeth of the key -model so that a cutting tool reproduces this shape on the blank by translation of said plate.

It is interesting that each of the two clamps is secured to said movable plate by means of a nut screwed around said shaft and being embedded in said plate, said nut comprising six notches in the plane of symmetry of each face of said hexagon, a the ends of a rod passing through said plate being held by resilient means inside one of said notches. The other end of said rod is advantageously outside said plate and comprises a head to facilitate manual release from said notch when an effort is opposed to said elastic means.

The present invention is described in more detail below using an exemplary embodiment illustrated with drawings. Of these:<ul><li>- Figure 1 shows in perspective an embodiment of the universal clamp for flat keys according to the present invention,</li><li>- Figure 2 is a top view of the vice of Figure 1 with a flat key establishment,</li><li>- Figure 3 shows the clamp of the preceding figures taken along the section defined in Figure 2,</li><li>- Figures 4 specify, through a detail of the section of Figure 3, different types of jaws for several kinds of keys and which can be carried by a given clamp according to the present invention,</li><li>- Figure 5 shows in top view how two clamps according to the present invention can be used to reproduce the teeth of a wrench on a similar blank,</li><li>- Figure 6 shows a detail of section BB defined in FIG 5,</li><li>- Figure 7 corresponds to the section CC of Figure 6 on which the trace of a vise according to the present invention with its key is reproduced superimposed.</li></ul>

An advantageous embodiment of the present invention is shown in Figure 1. The clamp 1 corresponding admits a cylindrical configuration with a vertical axis. More specifically, it is constituted by a 300 central shaft, a bottom plate 100 of hexagonal base, a top plate 200 in the form of a truncated cone with canted so that its base accepts the same hexagonal area than the lower plate, a turntable 400 and finally a head 500 shaped handle. In use, the blade of a flat key is arranged horizontally between the lower plate 100 and upper plate 200 as shown in Figure 2. This top view of the precise vise indeed how slightly less half of the width of the shank 22 of a key 2 is pinched between the two plates. And the head 23 of the key 2 she remains outside of the vise as its toothed part 21.

Figure 3 provides a better understanding of how the vise 1. On the vertical section in the plane AA of Figure 2 appears that the shaft 300 through the two plates and the turntable 400 to come connected by means of an external thread 350 and a nut 510 which extends from below the head 500 of handle. It is also secured to the lower plate 100 by means of a key 130. Between these two points of fastening of the shaft 300, the turntable 400 and the upper plate 200 are, in turn, free to slide on the shaft 300. it will be appreciated, under these conditions, that by screwing the handle head 500, it causes the tightening of the two plates towards one another.

To make their automatic separation when the 500 handle head is unscrewed the contrary, a spring 600 return is expected. Thereof surrounds the shaft 300 and rests on the lower plate 100. It also relies on the basis of a sleeve 430 which extends from below the turntable 400. Additionally, the upper plate 200 is secured to this sleeve 430 (by a force-fit for example). Thus, if only one enable its expansion, the spring tends it in away not only the turntable 400 but also the upper plate 200 of the lower plate 100.

During the ascent of these parts, a pivoting of the upper plate 200 relative to the lower plate 100, however, must be prevented. The following description will show the reason for this precaution. Anyway, the bottom plate 100 has for this purpose a mass of material 110 projecting upward. It has the shape of a parallelepiped-center relative to the axis of the clamp 1. A recess 210 complementary to this mass 110 is formed in the lower part of the upper plate 200. The mass 110 fits further in recess 210 on a significant height relative to the stroke of the nut 510. Thus, unscrewing the handle 500 head to release the key 2 does this mean forever by the separation of the two screw plates -to-vis their rotary movement about the axis of the grip 1.

This provision can finally understand the usefulness of the turntable 400. The bed of beads 440 it contains, in fact authorizes the clamping head 500 handle against the upper portion 410 of the crown without efforts twisting are transmitted at the socket of the mass 110 projecting on the lower plate 100 and the recess 210 of the lower part of the upper plate 200.

If it is so compelling that the two plates do not rotate with respect to each other is that they relate to the device of their opposite faces of the jaws 120 and 220 for receiving various kinds of bit keys. Each face of the hexagon is indeed devoted to a specific bit section. Figure 4 shows, with the aid of a detail of the section shown in Figure 3, the six sections of blade 22 a clamp 1 could for example welcome. In Figure 4-1, it is a type of wrench very current with a sharp reduction in thickness of the side 21 where the teeth are machined. The edge of the face of the corresponding hexagon then merely simple jaws, for example a vertical flange 220 under the top plate 200 and a horizontal extension 120 of the lower plate 100.

The very form of jaws can be used for bitting cross (see Figure 4-6) while the vertical distance between tight trays must be adapted to the thickness of one of the arms of the cross. More complex is the jaw profile receiving a bit in broken lines (see Figure 4-2). The vertical edge 220 of the top plate 200 then advantageously a tip and the lower plate 100, a complementary notch in the tip so that they work together to sandwich a corner of the broken line.

For bitting T, it is preferable that the two jaws facing each comprise a notch intended to accommodate a branch of the upper bar of the T (see Figure 4-3). Similarly the cylindrical bitting find it advantageous to be pinched between the jaws profiled in a circular arc (see Figure 4-4). Finally new keys made of two sheets bonded one to the other, one of the plates having an outer rib may be secured between a flange 220 provided with a recess complementary to the rib and a smooth extension of the tray 120 less than 100 (see Figure 4-5). Many other jaws profiles are of course possible depending on other types of non envisaged key here.

The vice 1 which has just been described, is advantageously used to reproduce the teeth of a key pattern on a blank whose key bits are identical. According to Figure 5, this can be achieved by attaching two clamps 1 according to the present invention on a mobile plate 3. One of vices then carries the key 2m model so that it has its toothed portion 21 parallel to the edge of the plate 3 in range of a probe 4. The other vise grips draft 2c in the same way to expose the attacks of a cutting tool 5. based on the information gathered by the probe 4, the plate 3 is translated parallel or perpendicular to the key bits so that the cutting tool 5 teeth again on the draft becomes 2c and a copy of the key model 2m.

For this system to work properly, it is appropriate that each clamp 1 is attached properly to the plate 3. Figure 6 shows how this can advantageously be achieved by means of a nut 31 which is screwed to the base of the tree 300 1. This vise nut 31 fits into effect in a recess 32 of the plate 3. When the clamp 1 is thus subject to the plate 3, however it is necessary to allow rotation of the shaft 300 to choose face of the hexagon which carries the key to be copied or machined. A rod 35 is provided for this purpose. It exceeds the one hand, outside the plate 3 and is provided with a head 36 facilitating its handling. At its other end, it has a tip 39 which can penetrate into a notch 33 of the nut 31 and the block and in the manner of a key. The nut 31 has done in six notches placed opposite each face of the hexagon (Figure 7). The rod 35 also passes through the plate 3 where an additional cylindrical recess has an enlargement 34 to accommodate a further spring 38 surrounding the rod 35. The spring 38 bears on one side of the enlargement 34 so that on a ring 37 secured to the rod 35 so that it always tends to maintain the tip 39 of the rod 35 within the notch 33 of the nut 31. the pressure is then unlocks the selected position by pulling on the head 36. It is advantageous to provide benchmarks on the vice 1 to facilitate its positioning as the key type to work.