The present invention relates to a device by which it is possible to protect and/or use drill bits so that, on the one hand, they are well- protected and, on the other hand, they stay firmly in the device in various conditions of use, although they may however be easily detached. In particular, the purpose of the device is to act as a sales package and means of preservation for drill bits.

Drill bits are sold both individually and in packages including a selection of bits. Individual bits are often packed in thin plastic "bags" which are transparent on one side. The bags tend to flatten and are meant to protect the bit. Because the package flattens, the replacement of the bit there after use is so awkward that it is often neglected. The above- mentioned drill bit selections may be found either in flat, hinged boxes or in round packages with detachable lids.

The bit selections have a disadvantage in that, because each user often needs only a few bit sizes, some sizes are bought for no purpose. Furthermore, a hinged package is very difficult to use. In particular, when wearing gloves, the placing of the drill bits into their holes is very difficult, if not impossible. Packages with lids tend to open in the tool box, and therefore the drill bits are often found on the bottom of the tool box, if they are found at all.

In any case, all the above-mentioned, familiar packages have the common disadvantage that they are extremely difficult to use on buildings, for example, where it is necessary to climb and only one hand is available in practice to handle the bit. Bit handling could also be made much easier in workshop conditions.

US patent publication 5,035,553 relates to a device in which several different-sized drill bits may be placed in a box-like structure. This is done by inserting them into parts shaped like sheaths. The sheath is equipped with inward protruding parts which fit the spiralled groove of the drill bit.

The device described above is not suitable as a sales package, nor can it be carried hanging from a loop attached to a construction worker's overalls, for example. Also, it requires that a separate sheath be made for each size of drill bit, because otherwise it will not work. Altogether, this is also an expensive solution for general use.

The purpose of the present invention is to bring about an improvement in the possibilities for use mentioned above and to create a device which is handy to use in practice. Simultaneously, a device made according to this invention will also act as a sales package and protect the bit during transportation etc. Furthermore, the purpose of the invention is to create a device which allows the easy handling of drill bits by one hand and which, at best, may be used without change for several sizes of drill bit. The afore-mentioned and other advantages and benefits of the invention have been achieved by a device whose distinguishing features are presented in the attached patent application.

The invention will now be described more exactly with reference to the attached drawings in which:

Figure 1 presents a general picture of a device according to one embodiment of the invention,

Figure 2 presents a second embodiment of the same device,

Figure 3 presents likewise a third embodiment of the device,

Figure 4 presents still another embodiment of the invention and

Figure 5 presents an advantageous method of attachment, for example to a loop on a construction worker's overalls, allowed by a device made according to the invention.

Figure 1 shows, therefore, a simplified side view of the basic structure of a certain device 1 made according to the invention. Device 1 has a sheath-like part 2, which is made of a suitable plastic, for example. The sheath part is joined advantageously to an attachment part 3, which may be of any type whatsoever. It may, for example, be a flattish part with a suitable means, such as hole 4, to join it perhaps to a metal wire bent into a loop as shown in figure 5.

Such a device according to the invention is not yet quite fit for use since if the drill bit 5 were merely pushed into the sheath and if the sheath were left to hang from a worker's belt, the drill bit would naturally fall out of the sheath. According to the invention this has been solved in such a way in this embodiment that depressed spirals 6 have been made by pressing the sheath part 2 inwards. The depressed spirals 6 correspond essentially with the spiralled grooves on the surface of the drill bit which carries the drilling waste up from the drilling hole.

The groove pr depression 6 or, if looked at from inside sheath 2, the protrusion, does not need to correspond exactly with the spiralled groove of drill bit 5. On the contrary, it is more an advantage if the degree of correspondence is not very exact. In practice the correspondence is formed naturally in such a way that a small amount of friction inevitably arises between sheath 2 and bit 5.

In practice, drill bit 5 is simply pushed into sheath 2 so that the bit revolves round the grooves or protrusions 6 by means of its own grooves.

Generally this requires very little force, especially if drill bit 5 is simultaneously helped to revolve. The spirals more or less suck the bit into the sheath. On the other hand, the bit does not easily detach itself so that, in order to remove it from the sheath, it must be grasped and helped to come out especially by a little turning. Herein lies the benefit of a device made according to this invention.

Figure 2 presents another embodiment of a device made according to the invention, in which the outer surface of the sheath part 2 (here shown in cross-section) is smooth and the part 7, which holds the drill bit by its grooves, has been achieved by attaching to the inner surface of sheath 2 a suitably wide and spiralling protrusion 7 which acts in the same way as the groove/protrusion presented in the previous embodiment. Naturally, protrusion 7 may also be made from the same piece as sheath 2, if it can be achieved in a suitable way. But the use of a suitably spiralled, cord-like solution which is merely attached to the sheath part 2 on its inner surface is easily possible.

Figure 3 presents a third embodiment of a device made according to the invention and a principle on which further embodiments of the invention may be based. A holder has been achieved for many sizes of drill bits. It includes a flexible part 8 or many parts 8 which, before putting the drill bit in place, are relatively near the spiral along which the drill bit is pushed into place in the package. Drill bit 5 is put into the holder as follows: the tip of bit 5, marked by number 5' in figure 3, forms an edge which is hooked under the flexible part 8 and raises it into the groove of the drill bit.

A considerable advantage of this embodiment is that the flexible part 8 keeps the bit 5 f mly in place in all conditions. It also has the advantage that it can just as easily hold a rock wall drill bit. In this case the tip is made with a hard metal piece which also includes an edge, thus allowing

the hooking of the flexible part 8 into the drill bit groove.

Figure 4 presents a variation of the embodiment in figure 3 in which the flexible part 8 is itself part of the package. It is a tongue, advantageously made of plastic, which performs the same duties as the flexible part described before.

The sheath part may, if desired, be equipped at its outer, free end with an expanded part whose purpose is to ease the putting of the bit into the entrance of the sheath 2. The size of the expanded part is large enough to facilitate the placing of the bit but not too large to hinder handling in general. If desired, the expanded part may be equipped with an enlarged protruding part pointed towards to the sheath part proper and which will guide the bit into the right place.

One further embodiment may be such that a brush, pointing towards the inside of sheath part 2, forms the means of holding the drill bit. If the hairs are stiff enough, some of them will support the groove of the bit and some will push against other parts of the bit. The brush may also be attached to the inside of the sheath in the form of a spiral.

Figure 5 presents an example of how sheath devices 2, each holding a desired size of bit 5 and attached to attachment parts 3, are hung by a metal wire bent into a loop 10. This wire loop may be opened for placing and removing drill bits and for attachment to a loop on a pair of overalls, for example. In this case the desired bit sizes are always available and can be removed or put back in awkward working situations with one hand.

The attachment part 3 may be any suitable type whatsoever and may be one and the same piece with the sheath part 2 or a separate part which is glued, welded or otherwise attached to the sheath part. The

attachment part 3 may be designed so that an individual sheath may be hung from a button on a pair of overalls, for example, without any separate hanging part as described above.

A practical example of one of the simplest possible embodiments of a device according to the invention is as follows. A piece of shrinkable plastic tube with a clearly bigger diameter than that of the drill bit is taken. The drill bit is pushed into one end of the tube far enough to cover a substantial proportion of the spirals, and the shrinkable plastic tube is heated so that it shrinks onto the drill bit. The part of the tube which overlaps the bit is flattened. As a result of the shririking, the tube presses partly into the grooves of the drill bit, thus forming a corresponding pattern. On cooling, the shrinkable plastic tube is permanently in the form of the desired drill bit. A hole may be made in the flattened part for the purpose of attachment.

Drill bits and corresponding devices may be advantageously equipped with devices according to the invention at the factory. Then the device will give protection during packaging, transportation and distribution. It will form a protective cover in the retail store and, if necessary, a representative sales package. At the same time, the device will act, as in the above description, as a practical means of preservation and use during work. When using a device according to the invention, the drill bits are always found and handled easily.

Furthermore, it is extremely easy to adapt a device made according to the invention in such a way that removal of the bit from the sales package can occur only by breaking a part of the package. A possible solution is one in which the bit is closed on two sides by a case formed from transparent plastic plate. The head of the case or sheath, where the edge of the drill bit is located, is used for attachment as described for the afore-mentioned embodiments. The part of the case around the other

end of the drill bit is designed to be wound free along a perforated line made in the sheath, for example.

Another possible solution is one in which a projection keeping the bit in place must be forcefully turned to the side in order to release the bit. In general the purpose of this kind of locking system is to decrease thefts of drill bits, which is a common problem in hardware stores.

It is clear that, on the basis of the above explanations, experts in this area will come up with numerous variations of devices according to the invention. But these variations must always be interpreted according to the sphere of protection given by the attached patent application.