NZ591638A - Shellfish processing apparatus using fluted rollers - Google Patents

Abstract

An apparatus (A) configured to orientate bivalve shellfish in a desired orientation comprises at least two adjacent elongate rollers (7), where each roller (7) has a substantially helical flute (9) extending along at least a major part of the roller (7), and the rollers (7) are rotatable about their respective longitudinal axes (L-L) in the same direction and at substantially the same speed. The rollers (7) are arranged so that the substantially helical flutes (9) of adjacent rollers (7) define a series of slots (11) between the adjacent rollers (7) that are not large enough for the shellfish to pass through, where each slot (11) has a major axis (MA) that extends generally in the same direction as the longitudinal axes (L-L) of the rollers and a minor axis (ma) transverse to the major axis. The profile of the substantially helical flutes (9) is such that the defined slots (11) are asymmetric across their minor axes (ma), and are of a shape that generally corresponds enough to the shape of a cross section of the shellfish to support the shellfish in the desired orientation. The rollers (7) are arranged such that the slots (11) transport the shellfish along the rollers (7) as the rollers (7) rotate.

Description

Received at IPONZ on 10 June 2011 NEW ZEALAND PATENTS ACT, 1953 No: Date: COMPLETE SPECIFICATION SHELLFISH PROCESSING APPARATUS I, BRUCE STANLEY DRABSCH, of 20 McLean Drive, Havelock 7100, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 3ll2170_2.doc 1 Received at IPONZ on 10 June 2011 2 SHELLFISH PROCESSING APPARATUS FIELD OF THE INVENTION This invention relates to a shellfish processing apparatus. More particularly, the apparatus is for orienting shellfish in a desired common orientation.

BACKGROUND Automated apparatuses for packaging or opening bivalve shellfish such as mussels typically 10 require the shellfish to be positioned a specific way on entry to the machine or apparatus.

Correctly orienting the shellfish for this purpose is traditionally a laborious and repetitive manual process. While some attempts have been made to automate shellfish orienting, automated systems have not been widely adopted by industry as they have generally been complex and expensive.

Mussels are difficult to orientate in a particular way, as they have elongate shells that are asymmetrical.

An automated shellfish opening machine is described in NZ patent 552626 that includes an 20 automated reorientation apparatus to correctly orient shellfish for opening. The reorientation apparatus in NZ 552626 uses sensors, a lighting system, and cameras to determine the orientation of an individual mussel or other shellfish on a conveyor. A robotic arm then individually picks up and reorients each mussel as required by the opening machine.

While the automated system described in NZ 552626 successfully reduces manual handling in reorienting shellfish, it is a complex and expensive system. In addition to a high capital investment, complex systems such as that in NZ 552626 have many moving parts as well as control systems and electronics, making them susceptible to both mechanical and hardware or software failures. Such systems are also generally expensive to run, require highly specialised 30 knowledge to maintain, and are difficult to keep clean.

United States food hygiene standards for cooked shellfish are stringent and require a high level of cleanliness of any machinery for processing the shellfish. It is critical that these standards are Received at IPONZ on 10 June 2011 3 complied with when processing shellfish for export to the US market. This is particularly an issue for apparatuses that process the shellfish following cooking of the shellfish.

There is a need for a simple, cost effective automated mechanical system for orienting shellfish, 5 particularly bivalve shellfish such as mussels for input into a machine or apparatus for further processing the shellfish, such as an opening or packaging machine, and that is also easy to clean.

In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a 10 context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents or such sources of information is not to be construed as an admission that such documents or such sources of information, in any jurisdiction, are prior art or form part of the common general knowledge in the art.

It is an object of at least preferred embodiments of the present invention to provide an alternative apparatus for orienting shellfish.

SUMMARY OF THE INVENTION In accordance with a first aspect of the present invention, there is provided an apparatus 20 configured to orientate bivalve shellfish belonging to a selected shellfish population in a desired orientation. The apparatus comprises at least two adjacent elongate rollers, each roller having a substantially helical flute extending along at least a major part of the roller, with the rollers being rotatable about respective longitudinal axes in the same direction and at substantially the same speed. The rollers are arranged so that the substantially helical flutes of adjacent rollers define a 25 series of slots between the adjacent rollers that are not large enough for the shellfish to pass through, each slot having a major axis extending in the same direction as the longitudinal axes of the rollers and a minor axis transverse to the major axis. The profile of the substantially helical flutes is such that the defined slots are asymmetric across their minor axes, and are of a shape that generally corresponds to the shape of a cross section of the shellfish to support the shellfish 30 in the desired orientation, and the rollers are arranged such that the slots transport the shellfish along the rollers as the rollers rotate.

In an embodiment of the invention, the apparatus is configured such that in use of the apparatus, the shellfish are transported from a position generally toward a first end of the rollers Received at IPONZ on 10 June 2011 4 to a position generally toward a second end of the rollers. A trailing portion of each slot behind the minor axis and toward the first end of the rollers may be longer than a leading portion of each slot in front of the minor axis and toward the second end of the rollers.

In an embodiment of the invention, the trailing portion of each slot may comprise two curved trailing surfaces, and the leading portion of each slot may comprise two curved leading surfaces, wherein the radius of curvature of the trailing surfaces is larger than the radius of curvature of the leading surfaces. In an alternative embodiment of the invention, the trailing portion of each slot may comprise two substantially straight trailing surfaces, and the leading portion of each slot 10 may comprise two substantially straight leading surfaces, with the straight surfaces angled relative to one another.

In an embodiment of the invention, a gap between sides of each slot at the position of its minor axis is approximately equal to the length of the leading portion of the slot.

In an embodiment of the invention, the rollers are substantially identical and each defined slot is symmetric across its major axis.

The longitudinal axes of the rollers may be substantially parallel and substantially horizontal, and 20 the major axis of each slot is generally parallel to the longitudinal axes of the rollers and the minor axis of each slot is generally perpendicular to the longitudinal axes of the rollers. Alternatively, the rollers may be inclined with their longitudinal axes at less than about 30 degrees from horizontal, and/or the longitudinal axes of the rollers may be non-parallel.

The rotation speed of the rollers, and/or the distance between adjacent rollers may be adjustable.

In an embodiment of the invention, the fluted part of each roller is at least about 700mm long. In an embodiment of the invention, the outer diameter of the fluted part of each roller is between about 70 mm and about 90 mm. In an embodiment of the invention, the outer 30 diameter of the fluted part of each roller is about 80 mm.

An apparatus may further comprise a drive arrangement operatively connected to each roller. The drive arrangement may be a gear arrangement, a belt drive arrangement, a chain that engages with sprockets mounted to each roller, or other suitable arrangement.

Received at IPONZ on 10 June 2011 The apparatus may further comprise means for disturbing the shellfish to assist with reorienting shellfish that are not in the desired orientation as they travel along the rollers. This means may blow air over the fluted part of the rollers, or may be a mechanical means such as a rotating brush.

In an embodiment of the invention, the shellfish population is a mussel population, such as New Zealand green-lipped mussels, and the slots are configured to support the mussel in a desired orientation with the hinge of the mussel directed downwardly and positioned toward a leading edge of the slot as the mussel is transported along the rollers. The mussel population may be 10 New Zealand green-lipped mussels having a long dimension of between about 85 mm and about 100 mm.

In an embodiment of the invention, the helical flutes have a pitch of 1.1 - 1.3 times the length of the shellfish, and/or the substantially helical flutes have a pitch of between about 100 mm and 15 about 120 mm, preferably about 110 mm, and/or the major axis of each slot is between about 100 mm and about 120 mm long and the minor axis of each slot is between about 20 mm and about 25 mm long.

The rollers may comprise a food-grade polymeric material.

The apparatus may further comprise a barrier or guide to direct shellfish towards the slots and/or to contain the shellfish within the apparatus.

In an embodiment of the invention, the apparatus comprises means for removing incorrectly 25 oriented shellfish from the apparatus and delivering them to a fluted part of the rollers towards a first end of the rollers.

According to a second aspect of the present invention there is provided a method of orienting bivalve shellfish belonging to a selected shellfish population in a desired orientation. The 30 method comprises: providing the apparatus outlined above with respect to the first aspect of the present invention; feeding shellfish onto the fluted part of the rollers towards a first end of the rollers; and Received at IPONZ on 10 June 2011 6 rotating the rollers in the same direction and at the substantially the same speed so that at least a majority of the shellfish fall into the defined slots and are oriented in the desired orientation, and the defined slots move the shellfish toward a second end of the rollers.

In an embodiment of the invention, shellfish are fed onto the fluted parts of the rollers at a rate such that between half and two thirds of the slots are occupied by a shellfish.

In an embodiment of the invention, the method further comprises the step of blowing air over 10 the shellfish on the rollers or using a rotating brush to disturb shellfish that are in less stable undesired orientations, thereby encouraging them to assume the desired orientation.

The shellfish may be fed onto the rollers using a vibrator or a conveyor.

The method may further comprise the step of rejecting incorrecdy orientated shellfish from the apparatus, and returning them to fluted part of the rollers toward the first end of the rollers.

Orientated shellfish from the apparatus may be transferred to a shellfish opening or packaging machine for example.

In an embodiment of the invention, the shellfish population is a mussel population. The mussel population may be New Zealand green-lipped mussels, and may be New Zealand green-lipped mussels between about 85 mm and 100 mm long.

The term "comprising" as used in this specification means "consisting at least in part of'; that is to say when interpreting statements in this specification which include "comprising", the features prefaced by this term in each statement all need to be present but other features can also be present. Related terms such as "comprise" and "comprised" are to be interpreted in a similar manner.

It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed 35 herein are hereby expressly disclosed. These are only examples of what is specifically intended Received at IPONZ on 10 June 2011 7 and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner.

To those skilled in the art to which the invention relates, many changes in construction and 5 widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting. Where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if 10 individually set forth.

As used herein the term "(s)" following a noun means the plural and/or singular form of that noun.

As used herein the term "and/or" means "and" or "or", or where the context allows both.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described by way of example only and with reference to the accompanying drawings in which: Figure 1 is an overhead perspective view of an apparatus in accordance with a preferred embodiment of the present invention; Figure 2 is a plan view of the apparatus of Figure 1; Figure 3 is a plan view of two adjacent fluted rollers of the apparatus of Figure 1; Figure 4 is an end view of the adjacent fluted rollers of Figure 3 (from the left side of Figure 3), showing a mussel supported in its desired orientation on the rollers of the apparatus; Figure 5 is a side view of a typical green-lipped mussel for processing in the apparatus of 30 Figure 1; and Figure 6 is an end view of the mussel of Figure 5.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Received at IPONZ on 10 June 2011 8 In this description the invention is described with reference to an embodiment of the invention suitable for orienting New Zealand green-lipped mussels that are also shown in the accompanying figures and specifically described. It will be appreciated that other embodiments of this invention may similarly be used for orienting different species of mussels, bivalves and 5 shellfish, without departing from the scope of this invention.

Figures 5 and 6 show a typical New Zealand green-lipped mussel M that can be processed in the preferred embodiment apparatus described below and shown in Figures 1 to 4. Green-lipped mussels are also known as green shell mussels. The mussel has a long edge 23, an adjacent sharp 10 end 25, a curved end 27 opposite to the sharp end, and a curved edge 29 opposite to the long edge 23 and having a hinge 21. The centre of gravity of a green-lipped mussel is positioned toward the hinge.

Green-lipped mussels are typically categorised as small, medium, or large, with medium-sized 15 mussels typically having a shell length of between about 85 mm and 100 mm, depending on their weight. Presendy, medium-sized mussels are considered the most valuable of the sizes, and are the mussels that are most often processed commercially. However, in different markets, different sizes of mussels may be most commercially important.

Referring to Figures 1 to 4, a preferred embodiment of the shellfish orienting apparatus A, which comprises a main support 1 having a first end support 3 and a second end support 5. The first end support 3 corresponds to an end of the apparatus at which the mussels to be oriented are introduced to the apparatus, and the second end support 5 corresponds to an end of the apparatus from which the mussels that have been oriented and singulated exit the apparatus. At 25 least two elongate rollers 7 are rotatably supported by the first end support 3 and the second end support 5, for example via bearings, so that the longitudinal axes L-L of the rollers are substantially parallel and in substantially one plane.

A helical flute 9 extends at a pitch angle a along at least a major part of each roller 7, preferably 30 between the first end support 3 and the second end support 5. Each helical flute has a first concave curved leading surface 9a, and a second concave curved trailing surface 9b, with a peak 9c of the flute formed between the curved leading surface 9a and the curved trailing surface 9b. The end of the trailing surface 9b opposite to the peak 9c connects at 9d to the end of the leading surface 9a of the next portion of the flute. At 9d, the trailing surface 9b and next leading Received at IPONZ on 10 June 2011 9 surface 9a are contiguous, and the trailing surface 9b is tangential to the next leading surface 9a. The leading surface 9a of the flute is curved differently to the trailing surface 9b of the flute, with the trailing surface 9b of the flute having a smaller radius of curvature than the leading surface 9a. The leading surface 9a of the flute is longer than the trailing surface 9b of the flute. The 5 flute profile is therefore asymmetric.

The rollers 7 can be configured so the helical flutes 9 of adjacent rollers define a series of convex slots 11 between adjacent rollers. Two adjacent short trailing surfaces 9b of the flutes form the curved leading surfaces 1 la of a slot 11, and two adjacent long leading surfaces 9a of the flutes 10 form the curved trailing surfaces 1 lb of a slot 11.

Each defined slot has a major axis MA parallel to the longitudinal axis LA of the rollers, and a minor axis 'ma' perpendicular to the longitudinal axis LA of the rollers. Each slot 11 is asymmetric across its minor axis, with a longer trailing portion of the slot positioned behind the 15 minor axis and a shorter leading portion of the length of the slot positioned in front of the minor axis. Each slot is preferably symmetrical across its major axis. In one embodiment, the gap between sides of each slot at the position of the slot's minor axis is approximately equal to the length of the leading portion of the slot in front of the major axis. Preferably, in the plane of the roller longitudinal axes L-L, the flute peaks 9c on adjacent rollers are aligned side-by-side. 20 Alternatively, the flute peaks 9c on adjacent rollers may be slightly misaligned, in the plane of the roller longitudinal axes L-L, so that the length of the major axis MA of the slot 11 is smaller than its length when the flute peaks are aligned. The rollers may be able to be retarded or advanced relative to one another, to change the size and shape of the defined slots.

The shape of the defined slots 11 generally corresponds to a typical cross section of the shellfish to be processed. Therefore, each embodiment of the invention may be suitable for orienting and singulating a specific shellfish population depending on the profile of the helical flutes 9 on the rollers. Figures 1 to 4 show an embodiment of the invention suitable for orienting New Zealand green-lipped mussels. In this embodiment, the slots formed between adjacent rollers correspond 30 to the outline of one of the shells of a typical medium sized New Zealand green-lipped mussel M cut along section line A-A in Figure 5 and section line B-B in Figure 6.

As can be seen in the plan view of Figure 2, the leading and trailing surfaces 9a, 9b of the flutes, and thereby the respective trailing and leading surfaces lib, 11a of the defined slots, are curved Received at IPONZ on 10 June 2011 or arcuate to maximise the contact area between the mussel and the surfaces of the slot when the mussel is positioned in the slot in its desired orientation. This increased contact area provides significant resistance to a mussel sliding out of the back of the slot, if the mussel in the slot is in the desired orientation.

Alternatively, in plan view, the leading and/or the trailing surfaces 9a, 9b of the flutes and thereby the trailing and/or leading surfaces lib, 11a of the defined slots could be straight, with the surfaces angled relative to one another. That is, on each side of the slot, the leading surface will be angled relative to the trailing surface, but the leading and trailing surfaces will be straight.

The slot will have a kite shape in plan view. However, when the trailing surfaces 1 lb of the slot are straight, there are fewer points of contact with the mussel and the mussel is more likely to move out the back of the slot as the rollers are rotated even if the mussel is in the desired orientation in the slot.

The slots could alternatively be provided with a combination of straight and curved/arcuate surfaces.

The shellfish cross section that the slot shape corresponds to is preferably one where the best fit of the shellfish in the slot is achieved, and the shellfish is at its most stable orientation in the slot.

For a mussel such as that shown in Figure 5 and 6, that is when the cross section plane A-A, B-B rests against the surfaces of the rollers in one of the slots, and when the hinge 21 is oriented downwardly and toward the leading end of the slot (in the direction of transport of the shellfish on the rollers). This most stable orientation of the shellfish in the defined slots 11 is the desired orientation. In this orientation, the centre of gravity of the shellfish is low relative to its points of contact with the rollers, which means that the mussels are unlikely to tumble as the rollers rotate. Depending on the configuration of the slot, in this desired orientation the shellfish will typically have up to four or five points of contact with the rollers, with the points of contact distributed around the shellfish.

Shellfish sitting on the rollers or in the slots in orientations other than this desired orientation have a centre of gravity higher relative to its points of contact with the rollers. The number of points of contact and the overall contact area between the shellfish and the rollers is smaller than for shellfish in the desired orientation, and the radius of curve of the trailing surface 1 lb is preferably greater than the radius of curvature of the shell of the shellfish in the slot when the Received at IPONZ on 10 June 2011 li shellfish is in an incorrect position. Therefore, the shellfish will be less stable and may be easily moved, rotated or flipped into the desired orientation when they are disturbed by the rotating rollers. With the configuration shown, the geometry and centre of gravity of the mussels will interact with the geometry of the slots, to flip or rotate the mussels into the desired orientation 5 and the mussels will be positioned in respective slots 11.

The radius of curvature of the leading surfaces 11a and/or the radius of curvature of the trailing surfaces lib may be non-constant. For example, the radius of curvature of the leading surfaces 11a may be smaller toward a forward end of the leading surfaces than toward a rear end of the 10 leading surfaces, and the radius of curvature of the trailing surfaces lib may be smaller toward a rear end of the trailing surfaces than toward a forward end of the trailing surfaces. Alternatively, as shown, the radius of the curvature of the leading surfaces 11a may be constant, and the radius of curvature of the trailing surfaces lib may be constant.

In the embodiment shown in Figures 1 to 4, the desired orientation of the mussel in the slots is one with the hinged, curved edge 29 down, the long edge 23 up, the sharp end of the mussel directed toward the exit end of the apparatus and the second end 7b of the rollers, and positioned against the trailing surfaces 9b of the flutes.

Figure 3 shows example dimensions of a preferred configuration of the apparatus suitable to singulate and orientate medium sized New Zealand green-lipped mussels such as those shown in Figure 4 and 6. In this embodiment, the length RL of the fluted part of the rollers is at least about 700 mm to about 800 mm long, with an outer dimension RD of each roller of about 80 mm. With improved efficiency, the rollers could be less than 700 mm long. The flute pitch FP is 25 about 110 mm, so up to seven slots 11 are defined per pair of adjacent rollers when the helical flutes on adjacent rollers are aligned. The flute pitch of about 110 mm corresponds to approximately 10% longer than the longest average length of a medium sized New Zealand green-lipped mussel to be processed, which is 85-100 mm, depending on the weight of the mussels. The flute profile on the rollers has a depth FD of about 10 to about 11 mm, and 30 preferably about 10.5 mm. The curve LSC of the leading surface 9b has a radius of about 340 mm and the curve TSC of the tangential trailing surface 9a has a radius of about 47 to about 57 mm, and preferably about 55 mm; however, these measurements are not critical. The pitch angle a is about 30 degrees.

Received at IPONZ on 10 June 2011 12 The dimensions described for the device may be varied to alter the performance of the device or make the device suitable for use in orienting different types and/or sizes of shellfish. For example, any one or more of the roller outer dimension, length, gap, flute pitch, curvature of leading and trailing surfaces, flute depth could be varied. Varying these parameters will affect the 5 performance of the apparatus. For example, the gap between the rollers affects the height of the mussels in the slots and thereby the rotation of the mussels, the outer dimension of the rollers influences the angle of the helix and angle of contact with the mussel, as well as deflection of the roller in use. The depth of the flute will influence the mussel rotation.

By way of example only, the outer diameter of the fluted part of each roller would typically be between about 70 mm and about 90 mm. The flutes could have a pitch of between about 100 mm and about 120 mm, depending on the shellfish to be processed. The major axis of each slot could be between about 100 mm and about 120 mm long, and the minor axis of each slot could be between about 20 mm and about 25 mm long. For some applications, the dimensions could 15 be smaller or larger.

Tests have shown the performance of the apparatus is more sensitive to the curve of the leading surfaces 9a of the flutes (the trailing surfaces lib of the slots) than the curve of the trailing surfaces 9b of the flutes (the leading surfaces 11a of the slots). If the curve of the trailing 20 surfaces of the slots is too shallow, the mussels tend to slide out the back of the slot as the rollers rotate and will not be transported along the rollers. If the curve of the trailing surface of the slot is too deep, the mussels do not pivot forward into the correct orientation.

The gaps between adjacent rollers 7 are such that the slots 11 between adjacent rollers are not 25 large enough for the shellfish to pass through. Preferably, the spacing of the rollers 7 is adjustable so the apparatus can be fine-tuned by the operator to accommodate variations in the shellfish population being processed. For example, the size and length to width ratios of green-lipped mussels can vary depending on the growing area of the mussels, and the amount of growth on the shells can also differ. Wider mussels or mussels having significant growth on their 30 shells may need larger gaps between rollers for effective orientation, for example. Varying the gaps between adjacent rollers will influence the contact angle between the shellfish and the rollers, and thereby the rotation of the mussels into the desired orientation.

Received at IPONZ on 10 June 2011 13 The rollers 7 are configured to be rotatable in the same direction and at the same speed, with a synchronised rotation. In a preferred embodiment, the rollers 7 are rotatable via a drive arrangement 13 operatively connected to the rollers 7 at a first end 7a. Alternatively the drive arrangement 13 could be operatively connected at or near the second end of the rollers 7b. The 5 drive arrangement may, for example, comprise a gear arrangement, a belt drive arrangement, a chain and sprocket arrangement with sprockets are mounted on the rollers, or another arrangement where rotation of the rollers is coupled.

If the rotation speed is too slow, the shellfish can more readily maintain a less stable undesirable 10 orientation in a slot. If the rotation speed is too fast the shellfish may not have time to settle into a slot or the shellfish may be more likely to be damaged by the apparatus, for example by the impact of a shell against a quickly rotating roller, they also may bounce off the apparatus or along the rollers. For the apparatus shown in Figure 3 and 4, the rollers are preferably rotated at between 60 and 180 rpm. The speed of rotation of the rollers may be adjustable by the operator 15 to influence shellfish orientation success.

In use, the shellfish to be orientated, for example medium sized green-lipped mussels, are fed onto the fluted part of the rollers 9 towards a first end of the rollers 7a, for example using a conveyor or a vibrator. The shellfish that are fed onto the rollers will typically have been cooked 20 by an upstream machine. Upstream of the conveyor or vibrator, a mussel grading apparatus would typically be provided, where the mussels are graded into small, medium and large sizes. The medium sized mussels having a length of between about 85 mm and about 100 mm would be delivered to the apparatus of the preferred embodiment.

The rollers 7 and helical flutes 9 of the apparatus are rotated in the same direction at the same speed via the drive arrangement 13. In the form shown, the rollers are rotated R in an anticlockwise direction when viewed from the first end 7a of the rollers, causing the defined slots 11 to move from the first end of the rollers 7a toward the second end of the rollers 7b. As the rollers 7 rotate, the shellfish fall into the defined slots 11 and are moved from a position toward 30 the first end of the rollers toward the second end of the rollers, in direction of travel T shown in Figure 1.

The apparatus uses gravity and the asymmetry of the shellfish to orientate the shellfish in the desired common orientation. Depending on the speed of rotation of the rollers and the Received at IPONZ on 10 June 2011 14 orientation of the shellfish when they lands on the rollers, the shellfish may flip over and/or move between two or more slots before finally settling into a slot in the desired orientation of the shellfish as shown in Figure 2 and 4. Most often the shellfish will settle into a slot by adopting the desired orientation, since this is the most stable orientation.

A greater number of slots per pair of adjacent rollers corresponds to a higher success rate as there is more opportunity for shellfish to move into their desired orientation. However, longer rollers also require more space and also are more expensive than shorter rollers providing fewer slots, that extra cost must be balanced against the diminishing improvements in success rates.

There will also be more deflection of the rollers between the end supports in longer rollers.

In some instances, not all shellfish will be positioned in a desired orientation. To increase the success rate of an apparatus A having rollers with a given flute length positioning shellfish in a desired orientation, the apparatus may comprise a means for disturbing the mussels in the slots.

For example, this may be a means for blowing compressed air onto the mussels in a direction across the rollers and above the surface of the rollers, to cause mussels in less stable orientations to rotate or move into another slot, increasing the chances of those mussels adopting the more stable desired orientation. Blowing air over the mussels in the embodiment shown in the accompanying drawings and discussed improved the success rate of the apparatus by about 10%.

Alternatively, the means for disturbing the mussels may be a mechanical means, such as a rotating brush. The apparatus may comprise an optical sensor to detect when mussels are not in a desired orientation as they travel along the rollers, and operate the means for disturbing the mussels in response to that detection.

The apparatus may also comprise a guide and/or barriers 15 along at least part of the most lateral rollers, to direct shellfish towards the slots and/ or to contain the shellfish within the apparatus as they are flipped around and move between slots. Preferably the shellfish are fed onto the rollers at a rate that causes between half and two-thirds of the slots to be occupied by mussels, and the remaining slots to remain empty. For example, for every three or four slots, two slots may be occupied by mussels. This provides sufficient room on the rollers for mussels to be manipulated into a desired orientation in the slots.

Received at IPONZ on 10 June 2011 As well as orienting the shellfish in the desired common orientation, the apparatus singulates the shellfish, that is, the apparatus delivers the shellfish to a position at or toward the second end of the rollers as separate units. This enables the shellfish to be more readily processed by downstream equipment.

In a preferred embodiment, the rollers are orientated with their longitudinal axes LA in a horizontal plane. Alternatively the rollers may be inclined at an angle of less than about 30 degrees to horizontal, such that the angle of incline is not enough to cause the shellfish to dislodge from the slots. The incline may be such that the second end 7b of the rollers 7 is either 10 higher or lower than the first end of the rollers 7a.

In a preferred embodiment, the main support 1 has an aperture 16 under the un-fluted second ends 7b of the rollers, through which the orientated shellfish exit the apparatus after they reach the end of the fluted part of the rollers nearest the second roller end 7b. The gap between the 15 un-fluted second ends 7b of the rollers is large enough for the shellfish to pass through, and preferably larger than the minor dimension of the slots. Preferably any shellfish that are not correctly orientated as they near the second end of the rollers are removed from the apparatus before they reach the aperture. Alternatively incorrectly orientated shellfish may be removed after they exit the apparatus, and delivered back to the vibrator or conveyor to be fed into the 20 rollers again. The apparatus preferably comprises means for removing or rejecting incorrectly orientated shellfish and returning them to the start of the rollers. For example, a camera based system could be used to identify mis-oriented shellfish and control a mechanism to remove these from the apparatus A and return the start of the rollers 7 for re-processing.

In a preferred embodiment, the aperture 16 in the main support is operatively connected to a shellfish opening machine or a packaging machine that requires shellfish to be fed into the machine in a correct orientation via a delivery means. Alternatively, this delivery means could be operatively connected to another part of the apparatus A, for example near the second end of the rollers 7b. If the particular orientation required by the orienting or packaging machine 30 differs from that achieved by the shellfish orienting apparatus A, a mechanism such as a turret could be used to turn the shellfish exiting the orienting apparatus so that they are correctly orientated for input into the attached machine.

Received at IPONZ on 10 June 2011 16 The fluted rollers can be manufactured from any suitable material. For example, the rollers could be manufactured from food-grade polymeric material such as PETP (polyethylene terephthalate). Alternatively the rollers could be manufactured from acetyl, or polyester, or stainless steel, for example.

At least preferred embodiments of the present invention provide a device for singulating and orienting shellfish in a desired orientation, which has a low number of moving components and high reliability. The smooth profile of the flutes ensures the apparatus is easy to clean to the standards required by the food industry.

Preferred embodiments of the invention have been described by way of example only and modifications may be made thereto without departing from the scope of the invention as defined by the following claims.

For example, the apparatus is shown as having three parallel rollers 7 that are all configured to rotate in the same direction. The apparatus could instead have as few as two rollers, or alternatively could have four or more rollers. Each roller will be preferably sized and configured in the same way, with the same flute configuration, so that shellfish can be oriented and singulated between any two adjacent rollers. Alternatively, in a configuration having only two 20 rollers the flutes could be shaped slightly differently on each roller, but with the same pitch.

The shape and size of the slot may change as it progresses down the roller. For example, the rollers could have rotational axes that are non-parallel (and that taper toward the trailing end of the rollers for example), or the outer surfaces of the rollers could be tapered. The configuration 25 will still be such that each slot has a major axis extending generally in the same direction as the longitudinal axes of the rollers and a minor axis transverse to the major axis, although it will be appreciated that the major axis of the slots cannot be exactly parallel to the axes of the rollers, as they have tapering axes. Generally, the major axis of the slot will be positioned evenly between the two axes of the rollers if the axes are non-parallel. Alternatively, or in addition, the flute 30 pitch could vary along the length of the rollers.

As green-lipped mussels grow, they tend to have a relatively constant ratio of about 3.6:1 of length to width. Also, different green-lipped mussels from different areas may have slightly different sizes. Accordingly, the operating parameters of the device are preferably adjustable to Received at IPONZ on 10 June 2011 17 accommodate the different sizes, such as the distance between the rollers, the rotational speed of the rollers, and the relative positioning of the rollers.

Claims (43)

Received at IPONZ on 10 June 2011 18 What I claim is:

1. An apparatus configured to orientate bivalve shellfish belonging to a selected shellfish population in a desired orientation, the apparatus comprising at least two adjacent elongate 5 rollers, each roller having a substantially helical flute extending along at least a major part of the roller, with the rollers being rotatable about respective longitudinal axes in the same direction and at substantially the same speed; wherein the rollers are arranged so that the substantially helical flutes of adjacent rollers define a series of slots between the adjacent rollers that are not large enough for the 10 shellfish to pass through, each slot having a major axis extending generally in the same direction as the longitudinal axes of the rollers and a minor axis transverse to the major axis; and wherein the profile of the substantially helical flutes is such that the defined slots are asymmetric across their minor axes, and are of a shape that generally corresponds to 15 the shape of a cross section of the shellfish to support the shellfish in the desired orientation, and the rollers are arranged such that the slots transport the shellfish along the rollers as the rollers rotate.

2. An apparatus as claimed in claim 1, wherein the apparatus is configured such that in use of 20 the apparatus, the shellfish are transported from a position generally toward a first end of the rollers to a position generally toward a second end of the rollers, and wherein a trailing portion of each slot behind the minor axis and toward the first end of the rollers is longer than a leading portion of each slot in front of the minor axis and toward the second end of the rollers. 25

3. An apparatus as claimed in claim 2, wherein the trailing portion of each slot comprises two curved trailing surfaces, and the leading portion of each slot comprises two curved leading surfaces, and wherein the radius of curvature of the trailing surfaces is larger than the radius of curvature of the leading surfaces. 30

4. An apparatus as claimed in claim 2, wherein the trailing portion of each slot comprises two substantially straight trailing surfaces, and the leading portion of each slot comprises two substantially straight leading surfaces, with the straight surfaces angled relative to one another. Received at IPONZ on 10 June 2011 19

5. An apparatus as claimed in claim 2, 3, or 4, wherein a gap between sides of each slot at the position of its minor axis is approximately equal to the length of the leading portion of the slot. 5

6. An apparatus as claimed in any one of the preceding claims, wherein the rollers are substantially identical and each defined slot is symmetric across its major axis.

7. An apparatus as claimed in any one of the preceding claims, wherein the longitudinal axes of the rollers are substantially parallel and substantially horizontal, and the major axis is 10 generally parallel to the longitudinal axes of the rollers and the minor axis is generally perpendicular to the longitudinal axes of the rollers.

8. An apparatus as claimed in any one of claims 1 to 6, wherein the rollers are inclined with their longitudinal axes at less than about 30 degrees from horizontal. 15

9. An apparatus as claimed in any one of claims 1 to 6 or 8, wherein the longitudinal axes of the rollers are non-parallel.

10. An apparatus as claimed in any one of the preceding claims, wherein the rotation speed of 20 the rollers is adjustable.

11. An apparatus as claimed in any one of the preceding claims, wherein the distance between adjacent rollers is adjustable. 25

12. An apparatus as claimed in any one of the preceding claims, wherein the fluted part of each roller is at least about 700mm long.

13. An apparatus as claimed in any one of the preceding claims, wherein the outer diameter of the fluted part of each roller is between about 70 mm and about 90 mm. 30

14. An apparatus as claimed in claim 13, wherein the outer diameter of the fluted part of each roller is about 80 mm.

15. An apparatus as claimed in any one of the preceding claims, further comprising a drive 35 arrangement operatively connected to each roller. Received at IPONZ on 10 June 2011 20

16. An apparatus as claimed in claim 15, wherein the drive arrangement comprises a gear arrangement.

17. An apparatus as claimed in claim 15 wherein the drive arrangement comprises a belt drive 5 arrangement.

18. An apparatus as claimed in claim 15 wherein the drive arrangement comprises a chain that engages with sprockets mounted to each roller. 10

19. An apparatus as claimed in any one of the preceding claims, further comprising a means for blowing air over the fluted part of the rollers, to assist with reorienting shellfish that are not in the desired orientation as they travel along the rollers.

20. An apparatus as claimed in any one of claims 1 to 18, further comprising a mechanical 15 means for disturbing the shellfish to assist with reorienting shellfish that are not in the desired orientation as they travel along the rollers.

21. An apparatus as claimed in any one of the preceding claims, wherein the shellfish population is a mussel population, and the slots are configured to support the mussel in a 20 desired orientation with the hinge of the mussel directed downwardly and positioned toward a leading edge of the slot as the mussel is transported along the rollers.

22. An apparatus as claimed in claim 21, wherein the mussel population is a population of New Zealand green-lipped mussels. 25

23. An apparatus as claimed in claim 22, wherein the mussel population is New Zealand green-lipped mussels having a long dimension of between about 85 mm and about 100 mm.

24. An apparatus as claimed in any one of the preceding claims, wherein the helical flutes have 30 a pitch of 1.1 - 1.3 times the length of the shellfish.

25. An apparatus as claimed in any one of claims 1 to 24, wherein the substantially helical flutes have a pitch of between about 100 mm and about 120 mm. Received at IPONZ on 10 June 2011 21

26. An apparatus as claimed in claim 25, wherein the substantially helical flutes have a pitch of about 110 mm. 5

27. An apparatus as claimed in any one of the preceding claims, wherein the major axis of each slot is between about 100 mm and about 120 mm long, and the minor axis of each slot is between about 20 mm and about 25 mm long.

28. An apparatus as claimed in any one of the preceding claims, wherein the rollers comprise a 10 food-grade polymeric material.

29. An apparatus as claimed in any one of the preceding claims, further comprising a barrier or guide to direct shellfish towards the slots and/or to contain the shellfish within the apparatus. 15

30. An apparatus as claimed in any one of the preceding claims, further comprising means for removing incorrectly oriented shellfish from the apparatus and delivering them to a fluted part of the rollers towards a first end of the rollers. 20

31. An apparatus as claimed in claim 1, substantially as herein described with reference to any embodiment disclosed.

32. An apparatus for orienting shellfish belonging to a selected shellfish population in a desired orientation, substantially as herein described with reference to any embodiment 25 shown in the accompanying drawings.

33. A method of orienting bivalve shellfish belonging to a selected shellfish population in a desired orientation, the method comprising: providing an apparatus as claimed in any one of claims 1 to 32; 30 feeding shellfish onto the fluted part of the rollers towards a first end of the rollers; and rotating the rollers in the same direction and at the substantially the same speed so that at least a majority of the shellfish fall into the defined slots and are oriented in the desired orientation, and the defined slots move the shellfish toward a second end of the 35 rollers. Received at IPONZ on 10 June 2011 22

34. A method as claimed in claim 33, wherein shellfish are fed onto the fluted part of the rollers at a rate such that between half and two thirds of the slots are occupied by a shellfish. 5

35. A method as claimed in claim 33 or claim 34, further comprising the step of blowing air over the shellfish on the rollers to disturb shellfish that are in less stable undesired orientations, thereby encouraging them to assume the desired orientation.

36. A method as claimed in claim 33 or claim 34, further comprising the step using a rotating 10 brush to disturb shellfish that are in less stable undesired orientations, thereby encouraging them to assume the desired orientation.

37. A method as claimed in any one of claims 33 to 36, wherein shellfish are fed onto the rollers using a vibrator or a conveyor. 15

38. A method as claimed in any one of claims 33 to 37, further comprising the step of rejecting incorrectly orientated shellfish from the apparatus, and returning them to fluted part of the rollers toward the first end of the rollers. 20

39. A method as claimed in any one of claims 33 to 38, further comprising the step of transferring the orientated shellfish from the apparatus to a shellfish opening or packaging machine.

40. A method as claimed in any one of claims 33 to 39, wherein the shellfish population is a 25 mussel population.

41. A method as claimed in claim 40, wherein the mussel population is a population of New Zealand green-lipped mussels. 30

42. A method as claimed in claim 41, wherein the mussel population is New Zealand green-lipped mussels between about 85 mm and 100 mm long.

43. A method as claimed in claim 33, substantially as herein described with reference to any embodiment disclosed.