NO347970B1

NO347970B1 - Apparatus and method for boning fish

Info

Publication number: NO347970B1
Application number: NO20220480A
Authority: NO
Inventors: Edward Carr
Original assignee: Edward Carr
Priority date: 2020-10-07
Filing date: 2022-04-28
Publication date: 2024-06-03
Also published as: GB202015866D0; WO2022074160A1; GB2600087A; EP4225037A1; NO20220480A1; DK202270227A1; GB2600087B

Description

APPARATUS AND METHOD FOR BONING FISH

Field of the Invention

The present invention relates to an apparatus and method for removing the pin bones from a fish fillet.

Background to the Invention

When fish are filleted the flesh is cut or sliced away from the backbone by cutting lengthwise along each side of the fish parallel to said backbone. Because the fish fillets will not contain the larger bones that run along the vertebrae, they are often referred to a “boneless”, however some fish species have smaller, fine intramuscular bones called pins located within the fillet.

Manual removal of pin bones from fish fillets is highly labour intensive and so efforts have been made to mechanise this process through mechanised pin-boning machines. Numerous pin-boning machines now exist on the market, mostly working on the principle of pulling individual pin bones from the fillet. Such machines work well on large fillets, for example salmon fillets, however they are less unsuitable for use with soft fleshed fish, for example whitefish and pelagic fish such as mackerel and the likes. US3570048A is an example of an apparatus with two pairs of circular knives for producing fish fillets free from pin bones.

It is therefore an object of the present invention to provide an improved, labour saving pin-boning apparatus

Summary of the Invention

In accordance with the present invention there is provided a pin bone removal apparatus, and a method of removing the pin bones from a fish fillet, as defined in the appended claims.

The aspects of the present invention can be practiced alone or in combination with one or more of the other aspects, as will be appreciated by those skilled in the relevant arts. The various aspects of the invention can optionally be provided in combination with one or more of the optional features of the other aspects of the invention. Also, optional features described in relation to one aspect can typically be combined alone or together with other features in different aspects of the invention. Any subject matter described in this specification can be combined with any other subject matter in the specification.

The aspects of the invention will now be described in detail with reference to the accompanying figures. Still other aspects, features, and advantages of the present invention are readily apparent from the entire description thereof, including the figures, which illustrates a number of exemplary aspects and implementations. The invention is also capable of other and different examples and aspects, and its several details can be modified in various respects, all without departing from the scope of the present invention. Accordingly, each example herein should be understood to have broad application, and is meant to illustrate one possible way of carrying out the invention, without intending to suggest that the scope of this disclosure, including the claims, is limited to that example. Furthermore, the terminology and phraseology used herein is solely used for descriptive purposes and should not be construed as limiting in scope. In particular, unless otherwise stated, dimensions and numerical values included herein are presented as examples illustrating one possible aspect of the claimed subject matter, without limiting the disclosure to the particular dimensions or values recited. All numerical values in this disclosure are understood as being modified by "about". All singular forms of elements, or any other components described herein are understood to include plural forms thereof and vice versa.

Language such as "including", "comprising", "having", "containing", or "involving" and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents, and additional subject matter not recited, and is not intended to exclude other additives, components, integers or steps. Likewise, the term "comprising" is considered synonymous with the terms "including" or "containing" for applicable legal purposes. Thus, throughout the specification and claims unless the context requires otherwise, the word “comprise” or variations thereof such as “comprises” or “comprising” will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Any discussion of documents, acts, materials, devices, articles and the like is included in the specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention.

In this disclosure, the words “typically” or “optionally” are to be understood as being intended to indicate optional or non-essential features of the invention which are present in certain examples but which can be omitted in others without departing from the scope of the invention.

Directional references such as “up”, “down”, “vertical”, “horizontal”, “above”, “below”, “left”, “right” are to be understood in the context of the normal orientation of an industrial apparatus for processing fish products.

With reference to the Figures, an example of use of the apparatus to remove the pin bones of a mackerel fillet will now be described.

Brief Description of the Drawings

Figure 1 is a schematic perspective front view of an exemplary pin bone removal apparatus in accordance with aspects of the invention;

Figure 2 is a schematic perspective rear view of the exemplary pin bone removal apparatus of Figure 1;

Figure 3 is schematic a side elevation of the exemplary pin bone removal apparatus of Figures 1 and 2;

Figure 4 is schematic a plan view of the exemplary pin bone removal apparatus;

Figures 5 is a detailed schematic end elevation of the exemplary pin bone removal apparatus;

Figures 6a, 6b and 6c are a series of a schematic end views of a cutting means of the exemplary pin bone removal apparatus in various configurations;

Figure 7 is an end elevation of an exemplary pin bone removal apparatus in use;

Figures 8a, 9a and 9c show an exemplary fish fillets pin-bonded by a pin bone removal apparatus and method in accordance with the invention;

Figures 8b and 9b show pin bone-containing flesh strips removed from the fish fillets of Figure 8a and 9a, respectively;

Figures 8c and 9d are schematic cross-sections of the fish fillets of Figures 8a and 9a, respectively; Figures 10a and 10b show cross sections of left and right sided fish fillets, respectively;

Figure 11 is a schematic perspective front view of an exemplary pin bone removal apparatus comprising a plurality of cutting arrangements;

Figure 12 is a schematic side elevation of the pin bone removal apparatus of Figure 11; and

Figures 13 and 14 are detailed schematic views of a cutting arrangment.

Detailed Description

With reference to Figures 1 to 4, there is shown an exemplary pin boning apparatus 1 in accordance with aspects of the invention, the apparatus being configured to remove the pin bones from fish fillets 90. The pin boning apparatus 1 comprises at least one cutting arrangement 10 and a fish fillet-supporting member 20. The cutting arrangement 10 is disposed across the fillet-supporting member 20 so as to cut the fillet 90 while supported on the supporting member 20.

The cutting arrangement 10 and the fillet-supporting member 20 may be provided as an assembly 50. Assembly 50 may be mounted upon a frame or stand 40 having ground engaging legs or members to form a free standing pin boning apparatus. Optionally, the apparatus 1 comprises an associated infeed conveyor 30. Optionally, infeed conveyor 30 is an endless feeder belt. Infeed conveyor 30 may be provided as a component connected to the pin boning apparatus 1, or may be a separate conveyor, for example a conveyor of a fish processing plant.

With reference to the example shown in Figures 2 and 5, cutting arrangement 10 and fillet-supporting member 20 are provided as an assembly 50. Assembly 50 comprises spaced apart side supports 51 between which the cutting arrangement 10 and the fish fillet-supporting member 20 are located. Assembly 50 further comprises one or more transverse cross members 52 and/or guide rails 53 which extend transversely between the upper ends of said side supports 51.

With reference to Figures 11 to 12, an exemplary pin boning apparatus 1 is shown comprising a plurality of said cutting arrangements 10. In this optional arrangement, which is particularly configured to remove the pin bones from a plurality of fillets simultaneously, the plurality of said cutting arrangements 10 are arranged in an array across and/or around the fillet-supporting member 21.

Optionally, the plurality of cutting arrangements are arranged in staggered and/or spaced apart relationship across one or more transverse guide rails 53 or cross members 52. Optionally, cutting arrangements 10 are arranged in pairs along each cross member 52 or transverse guide rail 53.

It will of course be understood that the number of cutting arrangements is not limited, and number of cutting arrangements may be employed in a pin boning apparatus in accordance with the present invention.

Preferably, the fillet-supporting member 20 is movable.

Optionally, fillet-supporting member 20 is a rotatable drum, rotatably mounted transversely between side supports 51. The axis of rotation of drum 20 is arranged substantially parallel with a guide rail 53.

Advantageously, the rotatable drum 20 incorporates a means to firmly retain a fillet 90 on its surface 21 throughout the conveying and pin boning process. Optionally, the means to retain a fillet 90 is adapted to engage the skin-side, or the surface of the otherwise skin-containing side, of the fillet.

Optionally, the means to retain a fillet 90 on the drum 20 is a chilled drum surface 21, whereby the chilled surface causes the skin, or the surface of the otherwise skincontaining side, of a fillet 90 to adhere to the drum 20 by freezing. Accordingly, the drum 20 may comprise a cooling means by which the temperature of the drum surface 21 is reduced. Preferably, the cooling means is configured to chill the drum surface 21 to approximately -30 degrees C.A drum 20 having a chilled drum surface may be referred to as a freeze drum.

Alternatively, the means to retain a fillet 90 on the drum 20 may be a vacuum suction means.

Advantageously, the use of a drum 20 having a means to hold a fillet 90 on its surface 21 ensures that the fillet 90 remains substantially immobile relative the drum 20 during pin boning. This ensures accurate cutting and integrity of the pin-boned fillet 90.

The or each cutting arrangement 10 is spaced apart from the rotatable drum 20. The or each cutting arrangement 10 comprises a pair of cutting blades 11a, 11b. Preferably, the cutting blades are rotatable cutting blades. Preferably still, the cutting blades are substantially circular rotatable cutting blades.

With reference to Figures 2, 5, 11 and 12, cutting blades 11a, 11b are arranged to rotate in a direction that converges with the direction of rotation of the drum 20 as shown by arrow R.

With reference to Figures 7 and 8a,8b and 8c, and as described in further detail below, each cutting blade 11a, 11b is configured to deliver one side 91a, 91b of a substantially U-or V-shaped cut 91 into a fish fillet 90 passing on the rotating drum 20. The respective sides 91a, 91b of the cut 91 are made along each side of the pin bone line of said fillet 90. In this way, the so-formed substantially U- or V- or wedgeshaped strip of flesh 92 containing the pin bones 93 (Figures 8b, 9b) are removed from said fillet 90 in a single step/pass cutting operation. As described further below, the portions of the pin boned fillet 90 at either side of the substantially U- or V-shaped cut 91 advantageously remain joined to each other.

With reference to Figures 1 to 4, the apparatus 1 optionally comprises an alignment apparatus 60 configured to place a visible marker 61, such as a laser beam, onto the infeed conveyor 30 and/or fillet support member 20, the marker defining an elongate line that is in alignment with the cutting blades 11a, 11b, and which assists a user to position the visible pin-bone line of a fillet 90 on said conveyor 30 and/or fillet supporting member 20 so that it is substantially in alignment with said cutting blades. Optionally, the alignment apparatus 60 is mounted to the cutting arrangement 10.

With reference to Figures 5, 13 and 14, each circular cutting blade 11a, 11b is mounted on an axle 112 and has a cutting edge 111 extending around its circumference.

Each axle 112 extends through a rotatable mount 113 that is pivotally mounted to a respective arm 12a, 12b of a carriage assembly 12. Optionally, as shown in Figure 5, the rotatable mounts 113 are located towards the respective terminal ends of said arms 12a, 12b.

Carriage assembly 12 comprises mounting means 13 (Figures 2, 4 and 13) configured for rotatable and sliding engagement with a guide rail 53 from which the carriage is suspended. Rotational positioning of the carriage assembly 12 about the guide rail 53 to alter the spacing of the cutting blades 11a, 11b from the surface 21 of the fillet supporting member 20 may be effected by an actuator 17 that extends between the carriage assembly 12 and a cross member 52 as shown in Figure 2. In this arrangement, extension and retraction of actuator 17 biases the lower end of the carriage assembly away from, and towards, the drum surface 21, respectively. Actuator 17 may be adjusted manually. Optionally, the actuator 117 is pneumatically operated. Optionally, actuator 17 may be operated automatically in response to one or more inputs from a controller (not shown) associated with the apparatus as described below. Actuator 117 and/or assembly 50 includes a hard stop to prevent the carriage assembly 12 from rotating so far in the direction of the fillet-supporting drum 20 that the cutting edges 111 of the cutting blades 11a, 11b make contact with the surface 21 of the fillet supporting member. Advantageously, carriage assembly 12 comprises a biasing means, for example a spring (not shown) to provide a positive pressure on said carriage assembly in order to hold the cutting blades 11a, 11b near the drum 20 in use.

Optionally, the apparatus includes means to independently alter the spacing of the respective cutting blades 11a, 11b from the surface 21 of the fillet supporting member 20 such that one cutting blade can come into closer proximity with the surface 21 of the fillet supporting member 20 than the other cutting blade.

Cutting blades 11a, 11b are motor driven. Drive may be provided to the cutting blades by a motor 15 located on the carriage assembly 12. Drive from the motor 15 may be transferred to each cutting blade 11a, 11b by any suitable drive transfer means, for example but not limited to, via pulley and belt arrangements 16 acting upon the respective cutting blade axles 112 as shown by way of example in Figures 1, 2 and 5. Alternatively, each cutting blade 11a, 11b may be independently driven by a respective dedicated motor. The or each motor may be either electrically, pneumatically or hydraulically powered.

With reference to Figure 5 and Figures 6a to 6c, and as described above, the axle 112 of each cutting blade 11a, 11b extends through a rotatable mount 113 that is pivotally mounted to respective arm 12a, 12b of a carriage assembly 12. By virtue of pivoting mounts 113, the circular blades 11a, 11b are independently movable, for example from a substantially parallel opposing configuration as shown in Figure 6a, to a mutually angled cutting configuration as shown by way of example in Figures 6b, 13 and 14. In this pivoted configuration, the cutting planes of the circular cutting blades 11a, 11b adopt a mutually intersecting orientation, however the cutting blades themselves do not intersect. Rather, the respective cutting edges 111 of the blades are brought into spaced-apart proximity with each other at a location proximate the drum surface 21. In this configuration, each rotating blade 11a, 11b is thus configured to cut the respective sides 91a, 91b of an elongate, substantially U- or V-shaped cut 91 into a fish fillet 90 as it passes on the rotating drum 20 below said cutting blades as shown by way of example in Figure 7.

With reference to Figure 6c, the axle 112 of one or both cutting blades 11a, 11b is movable in a linear direction to and from its mount 113 to enable adjustment of the cutting location, for example to pin-bone a fillet that is positioned off-centre on drum 20. Furthermore, this enables the width (w) of a cut to be varied.

With reference to Figures 8c and 9c, as the spacing of the cutting blades 11a, 11b from the surface 21 of the rotating drum is adjustable, the depth (d) of a substantially U- or V-shaped cut 91 can be varied, for example depending upon the dimensions of the fillets 90 being processed and the depth required to remove the pin bones 93As the planar orientation and mutual spacing of the opposing cutting blades 11a, 11b can be adjusted, the width (w) and shape of the substantially U- or V-shaped cuts can be varied. For example, in Figure 8c there is shown a schematic cross-section of a fillet having a substantially V-shaped cut 91 and in Figures 9c and 9b there is shown a schematic cross-section of a fillet having a substantially U-shaped cut 91 having one or more steeper sides 91a and a more pronounced planar base region having a width Wb.

It will therefore be understood that as the respective angles of the cutting planes of the cutting blades 11a, 11b of the apparatus can be independently varied, one side 91a, 91b of a substantially U- or V-shaped cut 91 may be cut at a different, e.g. shallower angle than the other side, depending on the location and orientation of the pin bones 93.

This is particularly advantageous at it has been observed that the pin bones are often not at 90 degrees relative to the skin of a fillet when lying on a flat surface as shown by way of example in Figures 10a, 10b and 10c in which the pin bone line P is oriented at approximately 15 to 20 degrees from the vertical, and is opposite (or mirrored) on left (Figure 10a) and right (Figure 10b, 10c) sided fillets. It has also been observed that the pin bone line is not straight at the bottom of a fillet where it meets the darker coloured swimming muscle.

Thus the ability of the cutting blades 11a, 11b of the cutting arrangement of the apparatus to independently vary in orientation enables the shape of a cut to be tailored from a V-shaped cut to a more U-shaped (or more square or flat bottomed U-shaped) cut in order to accommodate the specific pin bone anatomies of fillets presented to the apparatus for pin-bone removal, with the angle of the pin bone line P being followed by differently oriented left hand and right hand cutting blades 11a, 11b as the fillets pass below said cutting blades.

As shown by way of example, in Figures 13 and 14, one cutting blade, for example 11a, may be oriented such that its cutting plane is substantially upright relative to the surface of the rotating drum and the other cutting blade, for example 11b, is oriented at shallower angle with respect to the surface 21 of the rotating drum. It will be understood that that either cutting blade 11a or 11b can be oriented substantially upright (or substantially perpendicular) to the surface of the drum, with the other blade being oriented at shallower angle with respect to the surface 21 of the drum. Alternatively put, one blade may be oriented upright relative the drum surface than the other blade.

This arrangement, as shown by way of example in Figures 13 and 14 in which blade 11a is more upright than blade 11b, is particularly suited to imparting a substantially U-shaped, or flat bottomed U-shaped cut into a fillet as shown in Figures 9a and 9b to 9d. In this arrangement, the more upright blade 11a is arranged to make its incision on the right hand side of a pin bone line P of a right sided fillet 90 as shown in Figure 10b, with the shallower angled blade 11b making its incision on the left hand side of said pin bone line. It will be understood that this arrangement is be reversed for left sided fillets as shown in Figure 10a. Thus the respective first and second incisions made by blades 11a and 11b are configured to closely follow the angle of the pin bone line of a fillet. Accordingly, the pin bones are removed from the fillet within an optimally sized and shaped strip of flesh 92 with minimal excess fillet flesh wastage.

As shown in Figure 11, where there are a plurality of cutting arrangements 10 provided on an apparatus 1, they may be particularly arranged to cut the pin bones from left and right sided fillets.

Accordingly, the apparatus enables full control of the pin boning process so that fillets presented to the apparatus are cut in an appropriate, accurate and economical manner.

It will also be understood that the angular orientation of either or both cutting blades 11a, 11b can be varied during passage of a fillet such that the arrangement of cut delivered by the blades can be varied along the length of a fillet.

In an optional arrangement, the apparatus is configured to make a cut 91 having a depth (d) of approximately 2/3 the overall thickness of the fillet at the cut location.

Optionally, at its deepest point, the substantially U- or V-shaped cut is approximately 2-5mm clear of the skin side of the fillet.

Optionally, at its deepest point, the substantially U- or V-shaped cut extends to the flesh of the swim muscle of the fillet.

In an examples, the apparatus is configured to make a cut 91 having a length of approximately 2/3 the length of the fillet 90.

As noted above and with reference to Figures 7, 13 and 14 , the cutting blades 11a, 11b themselves do not intersect, but rather the respective cutting edges 111 of the blades remain in spaced-apart proximity from each other and the drum surface 21 during cutting. Thus the respective sides 91a, 92b of the substantially U- or V-shaped cut also do not intersect, and so the fillet 90 is not cut into two separate fillet pieces. Instead, the so-formed wedge shaped strip of flesh 92 (Figures 8a to 9d)) containing the pin bones 93 remains temporarily connected to the fillet 90 along its apex or base at the area of blade incision as the blades 11a, 11b incise. The resulting strip of flesh 92 containing the pin bones subsequently tears along its apex 94 as the strip 92 is pulled apart from the fillet 90 as the fillet travels onwards beyond the cutting arrangement 10, for example as the strip adheres to, and is pulled away by, a cutting blade 11a, 11b as shown in Figure 7, or by a strip removal member 80 provided between the cutting blades as shown in Figures 11, 13 and 14.and described below.

Advantageously therefore, a fillet pin-boned by the apparatus and method of the present invention is not split into two separate fillet sections, but rather remains as a singular pin-boned fillet joined along a common web of flesh 95 as shown in Figures 8a, 8c, 9a, 9c and 9d. Accordingly, the portions of the pin-boned fillet 90 at each side of the pin bone line remain connected. Advantageously, the so formed fillet is less susceptible to separating into separate portions compared to prior art pin-boning methods. Furthermore, said pin boned fillets are more susceptible for subsequent skinning with a much reduced risk of breakage into separate halves.

In an optional arrangement, the web of flesh 95 has a thickness (x) of approximately 2 – 5 mm.

In an optional arrangement, the web of flesh 95 substantially comprises the swim muscle of the fillet.

Furthermore, continuous attachment of a fillet 90 to the rotating drum 20 during and immediately after cutting ensures that the fillet and the strip of flesh 92 containing the pin bones 93 are pulled cleanly away from each other with an even force. This ensures repeatability and consistency of cut 91 delivered to fillets during continuous pin-boning operations.

With reference to Figures 13 and 14, the or each cutting arrangement 10 may optionally comprise a strip removal member 80 to tear away the strip of flesh 92 containing the pin bones along it apex 94 from a fillet 90. Strip removal member 80 comprises a plate 81 that is suspended between the cutting blades 11a, 11b, with an edge 82, optionally a lower edge, of said plate positioned in close proximity to the cutting edge 111 of one or both cutting blades 11a, 11b. It will be understood that while Figures 13 and 14 appear to show the strip removal member 80 contacting the cutting blade 11a at its cutting edge 111, in practice they are preferably slightly spaced apart. In certain applications however, for example depending up the respective materials employed, some contact between the strip removal member 80 and the cutting edge 111 of a cutting blade may be tolerated.

Strip removal member 80 may be suspended from a bracket 83. Bracket 83 may connect to a mount 113 of the cutting arrangement 10. In use, the edge 82 of the strip removal member 80 contacts the strip of flesh containing the pin bones that has been incised, or is being incised, along two sides, and the through surface adherence of said strip to the strip removal member 80, the strip is pulled away from the fillet along its apex 94. To augment the adherence of said strip to the removal member, suction means may be provided in association with the strip removal member. Optionally, the strip removal member is biased toward the cutting blade11a that is oriented more uprightly relative the rotating drum as shown in Figures 11 and 12.

With reference to Figures 1 to 3, the apparatus 1 optionally comprises a fillet detection means 70. The fillet detection means 70 optionally includes associated processing means (not shown) configured to receive the output of the detection means and to process said signal to identify any one or more of, but not limited to, the following parameters of a fish fillet located on the drum 20 and/or infeed conveyor 30: orientation; length; thickness; pin bone line location. Optionally, the processing means is configured to automatically control one or more operational and/or positional parameters of drum and/or the cutting arrangement 10, for example to locate the cutting arrangement 10 in cutting alignment with a fillet located on the drum, in response to the input received from the detection means 70. Optionally, the processing means is common with the processing means of the alignment means. Optionally, the processing means is the processor of a computerised computation device or integrated circuit or module.

Optionally, the operational parameters include any one or more of, but not limited to: the rotational speed of the rotatable knives 11a, 11b; the rotational speed of the drum 20; the speed of the infeed conveyor 30; the temperature of the drum surface 21.

Optionally, the positional parameters of a cutting arrangement 10, include any one or more of: the lateral positioning of the cutting blades across the drum surface 21; spacing of the cutting edges 111 of the cutting blades 11a, 11b away from the drum surface 21; relative planar orientation of the of the opposing cutting blades 11a, 11b; mutual spacing of the opposing cutting blades 11a, 11b.

Optionally, adjustment of the one or more positional parameters of a cutting arrangement 10 is effected by one or more suitable motors or actuators acting upon said cutting arrangement 10, for example but not limited to its mounting means 13, carriage assembly 12, or movable parts.

In examples, the fillet detection means 70 is a mechanical detection means. In examples, the fillet detection means 70 is an optical detection means. Optionally, the detection mean comprises a laser. Optionally, the fillet detection means 70 and the alignment means 60 are integrated. Optionally, the alignment means 60 comprises the fillet detection means 70 or vice versa.

Thus, a pin-boning apparatus in accordance with examples of the present invention is capable of automatically pin boning a variety differently sized fish fillets, or from a variety of fish species.

An example of use of the apparatus to remove the pin bones of a mackerel fillet will now be described.

With reference to Figure 1, a fillet 90 is placed skin side down on an infeed conveyor 30. Placement of the fillet 90 onto the infeed conveyor may be carried out manually, or automatically by a prior conveyor (not shown). Preferably, the fillet 90 is positioned longitudinally on infeed conveyor 30. Optionally, markings 31 may be provided on the infeed conveyor 30 and/or fillet supporting member 20 to indicate a preferred or optimal position. Preferably, the trace of an optical beam 61 on the surface of infeed conveyor 30 provides a positioning line with which the pin bone line of the fillet is aligned.

The fillet 90 is transported by the infeed conveyor 30 to a fillet supporting member, for example in the form of a rotatable drum 20. The skin, or the surface of the outside or otherwise skin-containing side, of the fillet 90 freezes upon contact with the drum surface 21 thereby adhering to said drum.

The apparatus detects the presence of the fillet (by optical sensor or by mechanical means) and the rotating blades 11a, 11b of the cutting arrangement 10 are moved into proximity to the drum surface 21. The angles and/or mutual spacing of the rotating knives are adjusted as required.

The rotating blades make incisions 91a, 91b of a cut 91 into the fillet 90 along each side of the pin bone line. The length of the incisions is adjustable. Optionally, at least one incision is made at an acute angle with respect to the surface of the drum.

As the cut 91 is performed, a shaped strip of flesh 92, substantially in the form of a wedge, containing the pin bones 93 is pulled away from the fillet 90. The strip of flesh 92 is subsequently removed from the apparatus for further processing.

The pin-boned fillet 90 remains adhered to the rotating drum 20 and is subsequently removed via a scraper (not shown). The pin-boned fillet 90 may optionally be skinned if required.

The apparatus and method of the invention renders pin boning of mackerel and other similar fish time and cost efficient, as well as ensures high quality accurately and cleanly cut coherent pin-boned fillets with minimal wastage of flesh.

Conveniently, the infeed conveyor 30, fillet-supporting member 20, and cutting blades 11a, 11b can move at high speeds making the apparatus highly productive.

The present invention is particularly suited to removing the pin-bones from very soft fish without damaging the fish flesh. By placing the cutting blades 11a, 11b over a chilled drum as the fillet passes enables full control of the depth of the cut while the fillet is secured flat on the chilled drum and therefore separation of the fillet is avoided. If present, the skin can be retained, or subsequently removed, depending on the end product specification. The option to retain the skin of the fillet is important for smoking wherein the skin keeps the oils in the fillet during smoking.

It will be appreciated that although the apparatus and method of invention as described herein have is particularly suited to processing mackerel fillets, the apparatus and method of the present invention are suitable for removing the pin bones of any fish species.

Modifications are possible within the scope of the present invention as defined in the appended claims.

Claims

1. An apparatus (1) for pin boning fish fillets (90), the apparatus comprising: a cutting arrangement (10) and a fillet-supporting member (20); wherein the cutting arrangement (10) comprises spaced apart first (11a) and second (11b) rotatable cutting blades, the spaced apart rotatable cutting blades being operable to cut respective convergent non-intersecting first (91a) and second (91b) angled incisions along the respective sides of a pin bone line of a fillet (90) located on said fillet-supporting member (20), the angled incisions (91a, 91b) defining a substantially V- or wedge shaped removable strip of flesh (92) containing the pin bones (93) of said fillet;

characterised in that the fillet-supporting member (20) comprises a rotatable drum having a means to retain a fillet on its surface (21) during cutting, the means comprising a chilled drum surface whereby said chilled surface (21) freezes the underside of a fillet to said fillet-supporting member (20) upon contact with the drum surface (21) thereby adhering the fillet to said drum.

2. An apparatus as claimed in claim 1, wherein the first (91a) and second (91b) incisions are made simultaneously.

3. An apparatus as claimed in claim 1 or claim 2, wherein the rotatable cutting blades (11a, 11b) are substantially circular rotatable cutting blades.

4. An apparatus as claimed in any preceding claim, wherein each cutting blade (11a, 11b) is mounted on an axle (112), each axle being located on a respective arm (12a, 12b) of a cutting arrangement carriage assembly (12).

5. An apparatus as claimed in claim 4, wherein each cutting blade axle (112) is located on its respective carriage assembly arm (12a, 12b) via a respective rotatable mount (113), each mount being pivotally mounted to said respective carriage assembly arm (12a, 12b).

6. An apparatus as claimed in any preceding claim, wherein the fillet-supporting member (20) is movable relative to the cutting arrangement (10).

7. An apparatus as claimed in any preceding claim, wherein the cutting arrangement (10) and the fillet-supporting member (20) are provided as an assembly (50).

8. An apparatus as claimed in claim 7, wherein the assembly (50) further comprises an infeed conveyor (30) arranged to convey fish fillets (90) to the filletsupporting member (20).

9. An apparatus as claimed in claim 7 or claim 8, wherein the assembly (50) comprises spaced apart side supports (51) between which the cutting arrangement (10) and the fillet supporting member (20) are located, and one or more transverse cross members (52) or guide rails (53) that extend transversely between said side supports (51).

10. An apparatus as claimed in claim 9, wherein the fillet-supporting member (20) is rotatably mounted transversely between the side supports (51), whereby the axis of rotation of the fillet-supporting member (20) is substantially parallel with the one or more transverse cross members (52) or guide rails (53).

11. An apparatus as claimed in claim 10, wherein the cutting arrangement (20) is mountable to the one or more transverse guide rails (53) or cross members (52).

12. An apparatus as claimed in claim 11 when dependent on any one of claims 4 to 10, wherein the cutting arrangement (20) is mountable to the one or more transverse guide rails (53) or cross members (52) via a mounting means (13) provided on the carriage assembly (12), the mounting means (13) configured for rotatable engagement about said transverse cross member (52) or guide rail (53), wherein rotatable movement of the carriage assembly (12) about said transverse cross member or guide rail alters the spacing of the cutting blades (11a, 11b) from the surface (21) of the fillet-supporting member (20).

13. An apparatus as claimed in claim 12, wherein rotatable movement of the carriage assembly (12) about said transverse cross member (52) or guide rail (53) is effected by an actuator (17).

14. An apparatus as claimed in claim 13, wherein operation of the actuator (17) biases the lower end of the carriage assembly (12) and thus the cutting blades (11a, 11b) away from, and towards, the fillet-supporting member surface (21).

15. An apparatus as claimed in claim 14, wherein the actuator (17) is automatically actuated in response to one or more inputs from a control means associated with the apparatus.

16. An apparatus as claimed in claim 4, wherein the actuator (17) and/or carriage assembly (12) includes a hard stop to prevent the cutting edges (111) of the cutting blades (11a, 11b) from contacting the surface (21) of the fillet-supporting member.

17. An apparatus as claimed in any one of claims 4 to 16, wherein the carriage assembly (12) comprises a biasing means to exert positive pressure on the carriage assembly to hold the cutting blades (11a, 11b) near the fillet-supporting member surface (21) in use.

18. An apparatus as claimed in any one of claims 6 to 17, wherein the cutting blades (11a, 11b) are arranged to rotate in a direction convergent with the direction of rotation of the rotatable drum (20).

19. An apparatus as claimed in any one of claims 8 to 18, further comprising an alignment means (60) configured to place a visible marking (61) onto the filletsupporting member (20) and/or infeed conveyor (30), the marker defining an elongate line that is substantially in alignment with the cutting blades (11a, 11b).

20. An apparatus as claimed in claim 19, wherein the alignment apparatus is provided on the cutting arrangement (10).

21. An apparatus as claimed in claim 19 or claim 20, wherein the alignment means (60) is a laser alignment means, wherein the visible marking (61) is the trace or beam of the laser incident on the fillet-supporting member (20) and/or infeed conveyor (30).

22. An apparatus as claimed in preceding claim, wherein the cutting blades (11a, 11b) are motor driven.

23. An apparatus as claimed in preceding claim, wherein the cutting blades (11a, 11b) are movable from a substantially parallel opposing configuration to a mutually angled cutting configuration.

24. An apparatus as claimed in claim 23, wherein in the angled cutting configuration, the cutting planes of the cutting blades (11a, 11b) adopt a mutually convergent orientation so that their respective cutting edges (111) are brought into spaced-apart proximity with each other at a location proximate the fillet-supporting member surface (21) to impart an angled cut (91a, 91b) to a fillet located on said surface.

25. An apparatus as claimed in claim 24, wherein one or more of the depth (d), width (w) and/or the respective angled cuts is independently variable.

26. An apparatus as claimed in claim 25, wherein the apparatus is configured so that at the deepest point, the depth of the angled cuts (91a, 91b) is approximately 2-5mm clear of the skin side of the fillet.

27. An apparatus as claimed in any preceding claim, further comprising a fillet detection means (70) and an associated processing means, wherein the processing means is configured to receive one or more outputs from the fillet detection means (70) and to process said signal to automatically identify any one or more of: the orientation; length; thickness; and/or pin bone line location of a fish fillet located on the fillet-supporting means (20).

28. An apparatus as claimed in claim 27 when dependent upon any one of claims 15 to 26, wherein the processing means is the processor of the control means associated with the apparatus, and is configured to automatically control one or more operational and/or positional parameters of the rotatable drum (20) and/or the cutting arrangement (10) in response to the input or inputs received from the detection means (70), wherein the one or more operational parameters comprise any one or more of the rotation speed of the cutting blades (11a, 11b) the rotation speed of the drum (20), the speed of the infeed conveyor (30), the temperature of the drum surface (21),

and wherein the one or more positional parameters of the cutting arrangement comprise any one or more of the lateral positioning of the cutting blades across the drum surface, the distance of the cutting blades from the drum surface, and/or the cutting angle of the cutting blades.

29. An apparatus as claimed in claim 27 or 28, wherein the fillet detection means (70) is a mechanical detection means.

30. An apparatus as claimed in claim 27 or 28, wherein the fillet detection means (70) is an optical detection means.

31. An apparatus as claimed in claim 30, wherein the fillet detection means (70) comprises a laser.

32. An apparatus as claimed in claim 30 or claim 31, wherein the laser of the fillet detection means (70) is common with the laser of an alignment means (60) of the apparatus.

33. An apparatus as claimed in any preceding claim, wherein the apparatus is configured so the depth of the substantially V- or wedged shaped strip of flesh containing the pin bones of a fillet is approximately 2/3 the overall thickness of the fillet at the cut location.

34. An apparatus as claimed in any preceding claim, wherein the substantially V-or wedge shaped strip of flesh containing the pin bones is temporarily connected to the fillet along an apex region during incision, and wherein the apparatus is further configured to pull said strip of flesh from the fillet as said fillet travels further beyond the cutting arrangement (10).

35. An apparatus as claimed in any preceding claim, wherein the apparatus is configured so that the substantially V- or wedge-shaped strip of flesh containing the pin bones are removable from said fillet in a single step/pass cutting operation

36. A method of removing the pin bones from a fish fillet, characterised by that the method comprises the steps of:

(a) placing the fish fillet skin side down on a conveyor (30);

(b) transporting the fillet to a rotating drum (20) comprising a chilled drum surface (21) whereupon said chilled drum surface freezes the underside of the fillet upon contact with the drum surface thereby adhering the fillet to said drum;

(c) moving cutting blades (11a, 11b) of a cutting arrangement (10) into proximity with the surface (21) of the rotating drum and substantially in alignment with the pin bone line of said fillet;

(d) simultaneously cutting first and second convergent angled incisions (91a, 91b) into the fillet along each side of the pin bone line of said fillet; and

(e) pulling the so-formed substantially V- or wedge shaped strip of flesh containing the pin bones as defined by the respective angled incisions from said fillet.

37. A method as claimed in claim 36, wherein step (a) comprises the sub-step of aligning the visible pin bone line of the fish fillet with a marking generated on the surface the infeed conveyor (30).

38. A method as claimed in claim 36 or claim 37, wherein step (b) comprises the sub-step of adhering the skin-side of the fillet to the drum (20) by freezing.

39. A method as claimed in any one of claims 36 to 38, wherein step (c) comprises the sub-step of adjusting the relative planar angles of the respective cutting blades (11a, 11b).

40. A method as claimed in any one of claims 36 to 39, wherein step (c) comprises the sub-step of adjusting the relative distance of the cutting edges (111) of the cutting blades (11a, 11b) from the surface of the rotating drum.

41. A method as claimed in any one of claims 36 to 40, wherein steps (c) and (d) and their sub-steps is/are carried out automatically in response to inputs from a fillet detection means (70).

42. A method as claimed in any one of claims 36 to 41, wherein step (e) is effected by adherence of the substantially V- or wedge shaped strip of flesh containing the pin bones to one of the cutting blades (11a, 11b).

43. A method as claimed in any one of claims 36 to 42, comprising the further step (f) of removing the pin-boned fillet from the rotating drum (20).