WO2003037091A1

WO2003037091A1 - Shellfish opener

Info

Publication number: WO2003037091A1
Application number: PCT/NZ2002/000225
Authority: WO
Inventors: David Walter Corbin; Brian Walter Corbin
Original assignee: CORBIN DIANE MARGRET ELLEN
Current assignee: CORBIN DIANE MARGRET ELLEN
Priority date: 2001-10-29
Filing date: 2002-10-29
Publication date: 2003-05-08
Anticipated expiration: 2004-04-29
Also published as: NZ515126A

Abstract

Shellfish, eg mussels, which have been at least partially cooked, are transported on cleated conveyor (1). The shells are partially open and, if correctly orientated, encounter an opening plate positioned above and parallel with conveyor (1). This plate cooperating with cleated, inclined conveyor (3), running in an opposite direction to conveyor (1), flips the upper shell halves over so the shellfish assume a flat (180°) state. As the shellfish continue they are sandwiched between conveyor (1) and press conveyor (6) which extends around end roller (9) so that the shellfish are bent beyond 180°. The shell halves are separated by this action and fall into respective sorting chutes (10, 11). A spinning bar, positioned just ahead of the opening plate, may be used to force the edges of shells further apart to assist the opening action.

Description

SHELLFISH OPENER

Field of the Invention The invention relates to apparatus for processing shellfish and in particular for opening shellfish.

Background to the Invention

The following discussion and invention are particularly directed at the Mussel industry. However, it will be apparent to the skilled addressee that much of the discussion is also relevant to other shellfish industries, which are not excluded from the scope of the invention.

To date shellfish have been opened by hand. No real success has been achieved in automating this process. This has caused a number of difficulties within the industry.

The shellfish industry, particularly the Mussel industry, has grown to the stage where a large number of openers are required. Finding enough staff for this function can be difficult. Even with a sufficient quantity of hand openers there is a limit on the daily output that can be achieved.

Further, shellfish opening is a highly repetitive task and, amongst other things, there is a danger of repetitive stress type injuries. This can have a significant cost in both monetary and social terms to the industry and to the public at large.

It is an object of the present invention to provide an apparatus for processing shellfish and in particular for opening shellfish which avoids or ameliorates the above-mentioned disadvantage, or which at least provides a useful alternative. Summary of the Invention

According to a first aspect of the invention there is provided a shellfish opening apparatus including:

main conveyor means for transporting unopened shellfish from a loading position to an unload position;

an opening plate positioned to intercept shellfish being transported on the main conveyor;

a flipping means mounted in juxtaposition with the opening plate;

a separator means at or near the unload position;

the arrangement being such that, in use, the main conveyor means presents the unopened or partially opened shellfish to the opening plate which engages between the shell halves which are then flipped open on the main conveyor to substantially 1 80 degrees by the flipping means, the main conveyor then moves the shellfish to the separator means which is adapted to bend the shellfish through an angle adequate to separate the joint between the two halves of the shellfish shell to thereby separate the shellfish halves at or immediately before the unload position.

Preferably the apparatus includes a loading means at the loading position of the conveyor.

Preferably the apparatus includes a spinner bar in front of the opening plate, the spinner bar being adapted to help orientate the shellfish correctly for the opening plate. Preferably the apparatus includes a sorting means at the unload position adapted to sort the separated halves of the shellfish.

The invention envisages that the opening plate is disposed above the main conveyor such that it engages between the shell halves of a partially open shellfish. The flipping means engages one of said shell halves and flipping the shell open to substantially 1 80 degrees. The separator means bends the shell halves back further thus severing the joint between the shell halves.

Preferably the flipping means is associated with an inclined conveyor which is positioned above the main conveyor. One end of the inclined conveyor is in juxtaposition with the opening plate. The inclined conveyor can have on the surface thereof a series of generally transverse cleats which are adapted to engage with an open or partially opened edge of one half of the shellfish to thereby flip the shell halves open to about 1 80 degrees.

Preferably the shellfish is partially open by at least partial cooking prior to being deposited onto the loading means.

Preferably at the unload position is a discharge conveyor having an incline of 45 degrees wherein empty shell halves are discharged to a first position and shell halves with shellfish meat are discharged to a second position.

According to a second aspect of the invention there is provided a mechanical method of opening a shellfish, the method including:

at least partially cooking the shellfish to partially open the two halves of the shellfish;

using a mechanical shellfish opening apparatus to open the partially open shellfish so the shell halves extend open to substantially 1 80 degrees; using the mechanical shellfish opening apparatus to bend the shellfish halves back further to sever the joint between the shell halves.

In a further aspect of the invention there is provided a shellfish, preferably a Mussel, opened using an apparatus or method as hereinbefore defined.

Further aspects of the invention will become apparent from the following description, which is given by way of example only.

Brief Description of the Drawings

The invention will now be described with reference to the accompanying drawings in which:

Figure 1 : illustrates a schematic of a mechanical shellfish opener according to the invention;

Figure 2: shows detail of A in Figure 1 to illustrate a first stage in the interaction between a shellfish and the apparatus during shellfish opening;

Figure 3: shows detail of A in Figure 1 to illustrate a second stage in the interaction between the shellfish and the apparatus during shellfish opening; Figure 4: shows detail of B in Figure 1 to illustrate a third stage in the interaction between the shellfish and the apparatus during shellfish opening. Figures 5(a) to (d): shows respectively technical drawings of a complete mechanical shellfish opener according to the invention in which:

(a) shows a plan view of the shell fish opener;

(b) shows a front view of the shell fish opener;

(c) shows an end view of the shell fish opener; and (d) shows a perspective view of the shell fish opener. Description of the Preferred Example

The invention will now be described with reference to a shellfish opening machine adapted to open mussels. However, it will be appreciated that an apparatus according to the invention could be used for opening different varieties of shellfish.

A schematic overview of the apparatus is illustrated in Figure 1 . There shown is a main conveyor 1 for transporting shellfish from a loading position 8 to an unloading position 7. Positioned above, and parallel to, the main conveyor 1 is an opening plate 2 (shown in detail in Figures 2 and 3). The opening plate 2 can be mounted on an adjustable bracket so that its height above conveyor 1 can be varied in order to adapt the apparatus for different varieties and sizes of shellfish. Positioned higher above main conveyor 1 and partially over opening plate 2 is a second and shorter inclined conveyor 3. Inclined conveyor 3 can also be mounted on adjustable brackets so that its height and incline can be adapted to suit different varieties of shellfish. Critical to the invention is that lower end 4 of the inclined conveyor 3 is in juxtaposition with the opening plate 2 and preferably is adjacent or just in front of an opening edge 5 of the opening plate.

Main conveyor 1 has ridges or cleats 1 6 at regular intervals such as at 300mm intervals. The cleats can be angled at 85° to the longitudinal axis of the main conveyor 1 and on its upper surface. Cleats 1 6 grip the shellfish and move the shellfish on the surface of the main conveyor 1 . Similar cleats 1 7 are positioned and orientated at 1 50mm intervals along the surface of inclined conveyor 3. Main conveyor 1 and inclined conveyor 3 travel in the direction of the arrows shown. In the area of opening plate 2 lower surface 1 7a of inclined conveyor 3 is moving in the opposite direction to the direction of movement of the upper surface of the main conveyor 1 . In the preferred embodiment main conveyor 1 is moving at approximately 52 meters per minute ( 1 51 RPM x 1 1 0mm diameter rollers). Inclined conveyor 3 moves at the same speed.

Extending between opening plate 2 and the unloading position 7 of main conveyor 1 is a "press" conveyor 6. The press conveyor 6 is positioned at an adjustable height above main conveyor 1 such that opened shellfish which have passed opening plate 2 are sandwiched between press conveyor 6 and main conveyor 1 . Press conveyor 6 extends around a roller 9 to create a curve at unloading position 7 of main conveyor 1 and downwardly at 45 degrees over a short section 1 9. Below this 45 degree section 1 9 are two sorting chutes 10 and 1 1 which lead to two further conveyors 1 2 and 1 3 respectively that carry shellfish halves from the apparatus for further processing.

Referring now to the loading position 8 of main conveyor 1 : a loading conveyor 14 brings shellfish to the shellfish opening apparatus. The loading conveyor 14 terminates in a chute 1 5 which deposits shellfish at the loading position 8 so that they spread across main conveyor 1 .

The remaining requirements for the shellfish opening apparatus are best described with reference to its method of operation. This is described in the following discussion.

Loading conveyor 1 4 delivers shellfish from a cooker (not shown) to the chute 1 5 which deposits them at the loading position 8 of main conveyor 1 . At this stage it is anticipated that a large proportion, possibly in the order of 90%, of shellfish will be partially or half open from the cooking process.

The shellfish travel on main conveyor 1 until they reach the opening plate 2. Figures 2 and 3 illustrate how the opening plate 2 engages with each shellfish. If a partially opened shellfish is orientated in the desired direction the opening plate 2 will enter between the partially opened shell halves 20a and 20b. This is illustrated in Figure 2. The shell half 20b of the shellfish in this position is pressed by a cleat 1 6 onto the main conveyor 1 while pressing against the opening plate 2. Cleat 1 7 on inclined conveyor 3 engages the upper most shell half 20a of the shellfish and movement of the conveyor 3 flips the shellfish open. To achieve the required timing between cleats 1 6 and 1 7 inclined conveyor 3 it may be necessary to adjust the speed of the inclined conveyor to be as much as one quarter of the speed of main conveyor 1 . To assist the correct engagement of the partially opened shellfish onto the opening plate 2, a spinning rod 21 is driven at high RPM in front of the opening plate 2. This spinning bar 21 is machined to a suitable shape as shown Figure 2. The shape is chosen so that the edges of the bar 21 will frictionaily engage with the surface of the shellfish or the edges of the partially open shellfish to force the edges apart.

During the "flipping" motion the lower shell half 20b is brought up underneath opening plate 2 and moves further along main conveyor 1 .

The aforementioned flipping motion results in the shellfish being flipped open to substantially 1 80 degrees. Main conveyor 1 can have no support under it in the area of the opening plate 2 so that it can be pressed down as needed to allow the shellfish to pass under the opening plate 2 as they are being flipped open.

Once past the opening plate 2 the two joined mussel halves 20a and 20b proceed along main conveyor 1 and are sandwiched between the main conveyor 1 and the press conveyor 6. Main conveyor 1 and press conveyor 6 can be driven at the same speed or slightly different speeds.

Near the unloading end 7 of main conveyor 1 , press conveyor 6 rolls around roller 9 and down at 45 degrees. When the 1 80 degree opened shellfish passes around roller 9 it is bent back thus breaking the joint joining the two shell halves 20a and 20b together. This action combined with the slightly different conveyor speeds, due to the conveyors going around the roller 9 at different diameters, separates the two halves 20a and 20b of the shellfish. One shell half contains meat. The other does not.

The two shell halves 20a and 20b are then free falling towards chute 1 1 . A spray pipe 22 has a jet of water streaming in the direction of arrow 23 towards the shellfish halves during freefall. The water jet tumbles the free falling shells, which jet separates the empty shell onto the rear chute 10, and the heavier meat shell onto the front chute 1 1 . The chutes 1 0, 1 1 then deposit the shells onto conveyors 1 2 and 1 3 to be carried away for further processing.

Referring back to the stage at which the partially opened shellfish engages with opening plate 2: if the shellfish is not half opened from the cooker or is of a shape or orientation which will not go over the opening plate 2 one of three things can occur.

Firstly, the shellfish can roll around in front of the opening plate 2 for a short amount of time. If the opening plate 2 has a transversely angled opening edge 5 the shellfish will make its way to the edge of main conveyor 1 during the rolling process. At the edge of main conveyor 1 can be a chute or reject belt which will deliver the shellfish back for further processing.

Secondly, the shellfish may go under the opening plate 2 whole. This is allowed because main conveyor 1 is unsupported beneath opening plate 2 and can press down to allow the whole shellfish to pass along to the next stage. If needed, the shellfish can be removed by hand sorters at a later stage.

Thirdly, because the lower surface 1 7a of the inclined conveyor 3 is moving in an opposite direction to main conveyor 1 the shellfish will be pushed back along main conveyor 1 for a short distance. It will be rotated by the cleats 1 6 and 1 7 during this action. It can then come forward again and if orientated in the correct direction it will engage the opening plate 2 in the desired manner.

It will be appreciated that one or more main conveyors can be placed side by side in a "lane" set-up to increase throughput of the apparatus.

Thus an apparatus according to the invention can take partially opened shellfish and separate the two shell halves. The two shell halves are then sorted onto alternative conveyors so that the shell half containing no meat can be discarded, if required, and the shell half containing meat can be taken for further processing. It may be desired that the shell halves containing meat are prepared for distribution/sale as is. Alternatively, the meat may be removed from the shell half for distribution/sale on its own.

By an apparatus according to the invention the time consuming and repetitive task of opening shellfish, particularly Mussels, can be automated thus reducing the requirement for large numbers of opening staff and ameliorating the problems associated with repetitive stress injuries.

Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth.

Although the invention has been described by way of example and with reference to a particular embodiment, it is to be understood that modifications and/or improvements may be made without departing from the scope or spirit of the attached claims.

Claims

1 . A shellfish opening apparatus including:

a main conveyor means for transporting unopened shellfish from a loading position to an unload position;

a flipping means mounted in juxtaposition with the opening plate;

a separator means at or near the unload position;

2. An apparatus as claimed in claim 1 which includes a loading means at the loading position of the conveyor.

3. An apparatus as claimed in claim 1 or claim 2 which includes a spinner bar in front of the opening plate, the spinner bar being adapted to help orientate the shellfish correctly for the opening plate.

4. An apparatus as claimed in any one of the preceding claims which includes a sorting means at the unload position adapted to sort the separated halves of the shellfish.

5. An apparatus as claimed in any one of the preceding claims wherein the opening plate is disposed above the main conveyor such that it engages between the shell halves of a partially open shellfish.

6. An apparatus as claimed in any one of the preceding claims wherein the flipping means engages one of said shell halves and flips the shell open to substantially 1 80 degrees.

7. An apparatus as claimed in any one of the preceding claims wherein the separator means bends the shell halves back further thus severing the joint between the shell halves.

8. An apparatus as claimed in any one of the preceding claims wherein the flipping means is associated with an inclined conveyor which is positioned above the main conveyor.

9. An apparatus as claimed in claim 8 wherein one end of the inclined conveyor is in juxtaposition with the opening plate.

1 0. An apparatus as claimed in claim 8 or claim 9 wherein the inclined conveyor has on the surface thereof a series of generally transverse cleats which are adapted to engage with an open or partially opened edge of one half of the shellfish to thereby flip the shell halves open to about 1 80 degrees.

1 1 . An apparatus as claimed in any one of the preceding claims wherein the shellfish is partially opened by at least partial cooking prior to being deposited onto the loading means.

2. An apparatus as claimed in any one of the preceding claims wherein at the unload position there is a discharge conveyor having an incline of 45 degrees wherein empty shell halves are discharged to a first position and shell halves with shellfish meat are discharged to a second position.

3. A mechanical method of opening a shellfish, the method including:

using a mechanical shellfish opening apparatus to open the partially open shellfish so the shell halves extend open to substantially 1 80 degrees;

using the mechanical shellfish opening apparatus to bend the shellfish halves back further to sever the joint between the shell halves.

4. A method as claimed in claim 1 3 using the apparatus as claimed in any one of claims 1 to 1 2.

5. A shellfish opened using an apparatus as claimed in any one of claims 1 to

1 2 or the method as claimed in claim 1 3 or claim 14.