The present invention relates to a device for the removal of fish bones, and especially free fish bones in pieces of fish.

Background for the invention

In mechanical or manual filleting of fish, it is customary to remove the spine with ancillary set rib bones and head from the fish. However, it will in many cases remain so- called "floating", i.e. free fish bones in fillets which are prepared in this way. Particularly when preparing raw (sushi) , cured, salted or dried fish such fish bones may remain in the fish fillets and must be removed manually when the fillets are given a finishing treatment.

Discussion of prior art

Earlier, it has been usual to remove such free fish boned manually be means of different tools. The most common has earlier been to use tweezers to remove the bones one by one. This is a cumbersome and time consuming task which in many cases increases the prise of such "fish bone-free" fillets.

From US Patent 4,771,511, a scissor like tool in the shape of a nip is known, which be consists of two crossed shafts or arms being hinged in the middle and where these shafts in their opposite ends are equipped with flat cooperating scoops or plates wherein the floating fish bones are held between the scoops or plates where after the fish bones are removed by pulling the tool axially outwards from the piece of fish from which the fish bones are to be removed.

However, such tools are encumbered with several disadvantages. The ability for this tool to fold on to the fish bones is determined by the distance between the

rotational axis and the plates holding the bones seen in relation to the distance between the handles of the shafts and the rotational axis of the shafts (the relation between the torque from the handles to the rotational axis and from the rotational axis to the plates) .

Such tool is most efficient if the distance between the handles and the rotational axis is large and the distance between the rotational axis and gripping plates at the same time is small. However, there is a practical limit for how large this ratio may be, as a large distance between the handles and the rotational axis will lead to a need to move the handles far from each other to open the gap of the scissors sufficiently to grip onto the fish bones. Normally, this distance is decided by the grip of a normal person. With this limitation and to open the gap between the gripping plates sufficiently, the distance between the rotational axis and gripping plates can not be too small.

These considerations will lead to a limited gripping force in the above mentioned tool. Considering that the free fish bones in question may stick quite firmly, such tool will in many cases be too weak to be adequate to use.

It is also known from US Patent 5,904,616 a device for the removal of free fish bones. This device is constituted by two rolls, one running inside the other, and where the inner roll has a somewhat higher speed than the outer roll which is rolled along the fish fillet where the loose fish bones are in such a way that the loose bones are gripped by the inner roll and are pulled out when the outer roll is moved over the piece of fish.

The disadvantages with such devices is that it will not always grip the present bones (that must pass through slits in the outer drum) and that the fish bones may become wedged between the two rotating drums (inner and outer drum) .

Therefore, there is a need for a device for the removal of loose and floating fish bones without the above mentioned disadvantages and at the same time gripping the present fish bones firmly and precisely and which is suitable for the removal of several bones at the same time and where the device is easy to use manually.

General description of the device according to the invention

The present invention relates to a device for the removal of fish bones from fish meat, where the device comprises two shafts or arms being hinged to each other in their end sections and where the shafts for a gripping surface there between for the fish bones to be gripped when the shafts are moved towards each other.

It is preferred that the gripping surface on at least on of the shafts is plane since such a plane design will help to lead the gripping surface under the present fish bones in such a way that they will come to rest towards the gripping surface in an improved manner since the bones will be exposed, also by guiding such plane gripping surface opposite the direction of the bones, so that they can be held between the gripping surfaces of the device when the shafts are moved towards each other. However, it is not necessary that this part of the gripping surface is even and it can also hold alternative embodiments such as undulated, dented, arced etc. However, since the fish bones to be removed normally lies in a mainly straight line in the piece of fish meat, it is preferred that this part of the gripping surface is straight.

The opposite and cooperating gripping surface on the other shaft of the device may hold alternative embodiments such as undulated, dented, arced etc. However, also here is it preferred that the surface is straight.

The two cooperating gripping surfaces may rest towards each other with one surface towards the other or with one edge towards the other edge without any overlapping of the edge area for gripping of the fish bones in question there between.

Furthermore, it is possible to provide one of the abutting surfaces with a sharpened edge so that the fish bones are further attached when the handles of the device are moved towards each other as the sharpened edge pierces a little into the bones. However, such a sharpened edge must not act as scissors, thereby cutting the fish bones. Adaptation of such a sharpened edge for cooperation with the other gripping surface of the device can be designed by a person skilled in the art without unnecessary experimenting. Examples of overlap between the gripping surfaces of the device according to the invention are given beneath with reference to the examples.

When removing fish bones with the device according to the invention, the device is pulled transversally out from the piece of fish after having attached the fish bones between the gripping surfaces formed by the handles . Alternatively, it may also be possible to arrange the rotational axis for abutment towards the piece of fish after having attached the fish bones between the gripping surfaces of the handles. This will also give the device according to the invention a better moment of force than previously known tools for removal of fish bones.

With the device for removal of fish bones according to the present invention, one or more fish bones can be removed at the same time. The number of fish bones being removed depends on the number of bones in the piece of fish being prepared, the size of the piece of fish, the density of fish bones, the size of the fish bones etc.

In conventional pieces of side meat from fish, for example from salmon (wild salmon or farmed salmon) or trout, but also from cod or coalfish, it is normal that the present fish bones lies with a distance of about 1 cm from each other. With a size of 20 cm in the gripping zone of the device according to the invention, in such cases, it will be possible to remove up to 20 bones at the time. However, this number is merely an example and also more or less bones can be removed at the time if it is possible under the present circumstances. A skilled person will easily assess what is suitable in each case.

An alternative embodiment of a tool for the removal of free floating fish bones may be formed from a device comprising a flat or curved plate wherein a slit is formed and where an edge from the slit with a number of slats forming gripping recesses for the fish bones, as edges are grinded for gripping into the fish bones. The slit can also be made from a separate dented work piece being attached to the plate.

Such tool may have a design similar to a potato peeler where the fish bones are lead inn between the teeth being present in the slit, when the tool is lead with the direction of the fish bones, to be held by the sharp edges being formed in the interspace between the teeth and drawn with the tool when it is moved further in the same direction. A possible embodiment of such tool is shown in fig. 8. However, this embodiment does not present a preferred embodiment of a device for the removal of fish bones, unlike the embodiments in the other figures.

Description of embodiments of the device according to the invention

The device according to the invention for the removal of fish bones from pieces of fish will now be further explained with reference to the attached drawings where:

β

Fig. 1 shows a first embodiment of the device according to the invention.

Fig. 2 shows the device in fig. 1 in a side view.

Fig. 3 shows a cross sectional view of the device in fig. 1 taken along the axis A-A.

Fig. 4 shows a cross sectional view of the device in fig. 1 taken along the axis B-B.

Fig. 5 shows a perspective view of the device in fig. 1.

Fig. 6 shows the device in fig. 1 in open position.

Fig. 7 shows the device in fig. 1 from the grip side of the device .

Fig. 8 shows a second alternative embodiment of the device according to the invention.

Fig. 9 shows a third alternative embodiment of the device according to the invention.

Explanation of a preferred embodiment::

In fig. 1-7 a preferred embodiment of the device for removal of fish bones according to the invention is shown. In the figures, unless otherwise stated, similar parts are referred to with the same reference number.

The device according to the invention comprises two arms or shafts 1, 2 being rotatably hinged to each other at a rotational axis 3 in their end sections and preferably by their outer end sections so that they form two levers there between whose axis of moment coincide with the rotational axis 3. The arms or shafts 1, 2 are preferably provided with holding parts such as handles. The arms or shafts 1, 2

comprise a region in the parts of the arms adjacent to each other that come to engagement with each other. In this region, the fish bones (not shown) will be held when the arms are pressed towards each other. The clamping power performed on the fish bones are decided by the moment formed between the arms 1, 2 in such a way that the clamping power performed on the fish bones will increase when they are arranged closer to the rotational axis, if the gripping power on the arms 1, 2 are the same in each case.

In its simplest form, the fish bone removal tool according to the invention may lie end to end in the gripping area between the arms or shafts 1, 2. However, it is preferred that this gripping zone is formed by edges 6, 7 lying in abutment over each other (see figs. 1, 3, 4, 6 and 7) . Such overlapping edge zones 6, 7 will entail a better grip when the fish bones are held between the shaft or arm parts 1, 2.

The edge zone 6, 7 can run over a part of the arms 1, 2, but it is preferred that this edge area runs along all of or mainly all of the part of the arms or shafts 1, 2 which is not comprised by the gripping parts 4, 5 and rotational axis 3. Such a preferred embodiment can be used to attach fish bones in such a way that a plurality of fish bones can be removed at the same time, if needed.

The edge parts 6, 7 may exist as an integrated part of the arms 1, 2, but can also be made in an other material than the arms or shafts 1, 2 and will then suitably be fixed to the arms 1,2. The edge parts 6, 7 can, for example, be made of stainless steel and the arms or shafts 6, 7 can be made of a plastic material. The attachments between the edge parts 6, 7 and the arms 1, 2 can for example be done by nailing, riveting, use of glue or screws etc and/or by a method corresponding to a method for attaching handles on scissors where a protruding part on the end section of the

arm is surrounded by an end part of a holding element in a plastic material.

To broaden the applicability of the device according to the invention, one or both of the outer edge areas 8, 9 of the arms 1, 2 can be provided with a scrape edge. This scrape edge can be used for example to scrape away fish scale, but it can also be used to initially scrape the fish bones to be removed is such a way that the are lifted upwards, for the inner edge areas 6, 7 of the shafts or arms 1, 2 to fasten the grip on the present fish bones more easily.

To easy the use of the device according to the invention, it is possible in an alternative embodiment for provide for example the rotational axis 3 with a pull-back spring (not shown) to hold the arms 1, 2 from each other. Alternatively, such spring may be arranged on a suitable region of the arms 1, 2, for example adjacent to the line A-A in fig. 1. When arranging such pull-back spring on the rotational axis 3, the spring can be a torsion spring, whereas it can be a spiral spring or a leaf spring when arranged on one or both of the arms 1, 2. When the fish bones are pulled out from the piece of fish meat, such a pull-back spring will ease or make it unnecessary to use power to open the device for disposal of the loose fish bones from the grip between the arms 1, 2.

Regarding the material the device according to the invention is made of, it can be any suitable material such as aluminium, an aluminium alloy, stainless steel, a steel alloy, plastic material or a composition of different materials. To improve the comfort, the device according to the invention, for example the handle parts 4, 5 of the arms 1, 2 can be coated with a softer rubber or plastic material. It is preferred that the device according to the invention, in the part which is not gripping onto the fish bones, is made of a plastic material with a coarse surface to obtain a safe grip of the device during use.

The device according to the invention will be further explained below with reference to certain examples.

Example 1

The device according to this first embodiment of the invention is shown in fig. 1 and includes two shafts or arms 1, 2 with a total length of 19 cm. 8 cm of these arms 1, 2 is constituted by handles 4, 5. The handles 4, 5 are mainly symmetrical and bend upwardly for a better hold of the handles 4, 5 during use of the device. The arms 1,2 are rotatably attached to each other at the top region via a rotational axis 3. The rotational axis 3 is shaped as a hinge with a central cavity. The outer edges of the arms 1, 2 are formed as scrape edges. The inner edges 6, 7 of the arms are straight and comprises an overlapping edge region of 0,5 cm. The arms 1, 2 of the device are made in PVC with a coarse surface. The inner edges 6, 7 of the arms are made of stainless steel. (In an embodiment according to this example it is also possible to make the arms of stainless steel. )

Example 2

The device according to this third embodiment of the invention if shown in fig. 9 and includes two arms 1, 2 with a total length of 20 cm. 7 cm of the arms 1, 2 is constituted by a holding part in the form of handles 4, 5. The handles in this embodiment are asymmetrical, nor bent upwards and adapted to a right hand grip, so that one handle part 4 is adapted for a thumb and the other handle part 5 is adapted to accommodate the other fingers of a hand. It is also possible to adapt the holding part for a left hand grip. The arms 1, 2 are rotatably attached to each other in their top spot 3. The rotational axis of top spot 3 according to this embodiment is provided with a pull-back spring (not shown) holding the arms 1, 2 from each other. One of the arms 1 of the device has a sharpened

outer edge forming a straight scrape edge running along mainly all of the arm 1 (not being a part of the handle 4) . The inner edge of the arm 1 forms a straight edge. The inner edge of the opposite arm 2 lies adjacent to and overlapping the straight inner edge of the arm 1 with an overlapping zone of about 1 mm. The inner edge of the opposite arm 2 is made corrugated with a wave trough of 1 mm. All parts of this device are made of a thermoset plastic (cured polyethylene) .

Example 3

The device according to this embodiment is ^' shown in fig. 8 and is formed by a shaft or arm 2. The length of the shaft or arm is 17 cm. A suitable handle is attached to the shaft or arm 2 where attaching spots for the attachment of such handles are indicated. A comb 15 with teeth 13 and gaps 14 between the teeth is connected with the shaft 2. The shaft 2 according to this embodiment is straight and is provided with a sharpened outer edge in the outer edge area. The inner edge area is also straight.

The comb part 15 of the device according to this embodiment is toothed and lies in a distance from the shaft 2 in such a way that a slit is formed between the two shaft parts 2, 15. The teeth 13 of the arm 15 are 5 mm long. The slit formed between the arm part 2 and the arm part 15 has an opening of 2 mm. Furthermore, the bottom 14 between the teeth 13 are grinded to form an sharp edge being able to grip into (but not cut) the fish bone in question, thereby holding the fish bone between the teeth 13 for attachment of the fish bones in the opening 14 in order to pull them out from the piece of fish being worked with.