Method and apparatus for opening bivalve molluscs

Abstract

This invention relates to a method of shucking bivalve molluscs of the type having a body (11) enclosed within a two-part shell (12) comprising a first shell (13) and a second shell (14) each having a peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge (17), and wherein the body includes at least one adductor muscle (20) having a first end that is connected to the first shell and a second end that is connected to the second shell. The method includes creating an opening (25) in either the first shell 13 or the second shell (14) and using a blade (76) of an adductor cutter (50) that has been threaded through the opening to sever the adductor muscle.

Description

[0001] METHOD AND APPARATUS FOR OPENING BIVALVE MOLLUSCS

[0002] This invention relates to both a method and apparatus for opening an oyster .

[0003] This invention has particular but not exclusive application to both a method and apparatus for opening an oyster and wherein reference will be made to same . However, it will be appreciated that the invention may also have application to both a method and apparatus for opening other bivalve molluscs, such as clams, scallops and mussels .

[0004] Oysters typically include a soft body that is enclosed within a rough, generally irregular shaped, two-part shell comprising a bottom shell or left valve that resembles an open topped receptacle or cup and a substantially flat top shell or right valve .

[0005] The peripheral shapes of the bottom and top shells of an oyster generally complement each another . Their shape may generally resemble that of a tear drop or a pear, and each may include a first end portion that is narrow and / or pointed and an opposing second end portion that is often much wider and generally having a curved shape . The top shell is typically connected to the bottom shell by a hinge, which is located near the pointed end of both shells and adj acent to a conical shaped structure associated with the bottom shell known as the umbo .

[0006] Both the top and bottom shells each include a ragged, often sharp, peripheral edge portion commonly referred to as a fringe and wherein, when the two shells are in their closed position, the fringe of the top shell is often located behind the fringe

[0007] tHAG02103de script ion 14 January2026of the bottom shell which generally extends upwardly and outwardly therefrom so as to form of a protective lip .

[0008] The oyster' s body includes a muscle, commonly referred to as the adductor muscle, which runs through the oyster' s body, and which connects the top and bottom shells together . Like most bivalve molluscs, the adductor muscle is the only point of attachment between the oyster' s body and its shell . When you are holding an oyster with the bottom shell facing down and the hinge facing towards you, the adductor muscle will be located on the right side of the shell' s longitudinal axis and generally midway between its opposing end portions .

[0009] When the adductor muscle contracts, the top shell will tightly close the receptacle of the bottom shell such that there will be very little if any gap between the fringe of the top shell and the fringe of the bottom shell and wherein access to the fringe of the top shell will be at least partially protected by the fringe of the bottom shell . When the adductor muscle relaxes, the rounded end portions of the top and bottom shells will separate thereby creating a significant gap between the fringes of the two shells .

[0010] Many people enjoy eating the body of the oyster . However, removing the body of the oyster from its protective two-part shell, known as shucking, is difficult and can be quite dangerous in that the person may injure themselves quite severely.

[0011] While there are many methods for opening an oyster, most involve the use of a knife or a similar tool having a handle, a pointed end and at least one cutting edge that extends rearwardly from the pointed end in the general direction of the handle .

[0012] tHAG02103de script ion 14 January2026One method involves using one hand to either hold the oyster or to press down on the oyster, which is resting on a work surface, while inserting the pointed end of the tool, which is being held in the other hand, into the hinge and then twisting the tool so as to tear the hinge apart .

[0013] The cutting edge of the tool, which is located between the top and bottom shells, may then be slid towards the opposite end of the two-part shell such that the cutting edge severs the adductor muscle thereby effectively breaking the connection between the top and bottom shells .

[0014] The tool may then be used as a lever to separate the top shell from the bottom shell thereby exposing the body of the oyster .

[0015] The cutting edge of the tool may then be positioned between the body of the oyster and the bottom shell, and between the adductor muscle and one end of the bottom shell, before sliding the cutting edge towards the opposite end of the bottom shell, such that the cutting edge severs the adductor muscle thereby separating the oyster' s body from the bottom shell .

[0016] Alternatively, instead of using the tool to break the oyster' s hinge, some people prefer to insert the pointed end of the tool between the fringe of the top and bottom shells and generally opposite the hinge, before using the tool as a lever to partially prise the top and bottom shells apart . Having done so, the cutting edge may be slid between the top and bottom shells so as to cut the adductor muscle in a manner similar to the other method .

[0017] Regardless of which method is used, it has been observed that considerable force must be applied to the tool so as to penetrate

[0018] tHAG02103de script ion 14 January2026the hinge or create a gap between the fringe of the top shell and the fringe of the bottom shell and wherein any unintentional sliding of the tool relative to the oyster may result in the pointed end of the tool piecing the person' s hand that is holding the oyster and / or the cutting edge cutting the person' s fingers .

[0019] Bacteria like Mycobacterium szulgai or marrinum can be present in shellfish, including oysters . If the bacteria should enter a cut on the skin, the bacteria can cause infections that may spread to tendons, bones, and other parts of the body.

[0020] It has also been observed that using the aforementioned tool in the manner described may cause fragments of the two shells to break away and wherein the fragments may become embedded in the person' s hands or eyes . In the case of the eye, this can lead to severe inflammation and, in some instances, blindness .

[0021] Further, the repetitive motions and awkward positions required for shucking can lead to musculoskeletal disorders in the hands, wrists, and shoulders .

[0022] For these reasons, it is recommended that persons should only use tools that have been designed specifically for shucking oysters and that they wear protective gloves and eyewear .

[0023] It is therefore an obj ect of the present invention to provide both a method and apparatus for shucking oysters which will alleviate at least some of the potential hazards associated with the prior art and which will be both reliable and efficient in use .

[0024] With the foregoing and other obj ects in view, this invention relates to a method of shucking bivalve molluscs of the type

[0025] tHAG02103de script ion 14 January2026having a body enclosed within a two-part shell comprising a first shell and a second shell each having a peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge, and wherein the body includes at least one adductor muscle having a first end that is connected to the first shell and a second end that is connected to the second shell, said method including:

[0026] providing a first tool that is capable of creating an opening in the mollusc' s shell ;

[0027] using the first tool to make an opening in either the first or second shell adj acent the adductor muscle;

[0028] providing a second tool of the type having a handle at one end and a cutter located at the opposite end and wherein the cutter is capable of severing the adductor muscle, said handle being connected to said cutter by a stem;

[0029] threading the cutter through the opening such that the cutter is located adj acent a portion of the shell that surrounds the opening;

[0030] at least partially rotating the handle of the second tool such that the cutter severs the adductor muscle which will in turn enable the peripheral edge portions of the two shells to be easily separated such that there exists a gap therebetween;

[0031] providing a lever having a first end portion that is adapted for location within the gap and an opposing second end portion that is capable of being used as a handle;

[0032] locating the first end portion in the gap between the two shells and applying a force to the handle in a direction that is generally perpendicular to a plane generally containing said shells which is at least sufficient to displace one of the shells relative to the other so as to permit removal of the body.

[0033] Preferably the bivalve mollusc is an oyster and wherein the first shell or top shell is substantially flat and wherein the

[0034] tHAG02103de script ion 14 January2026second shell or bottom shell resembles a receptacle . In particular, the bottom shell crudely resembles a bowl having curved sides for holding the oyster' s body which will be floating in a fluid known as oyster liquor .

[0035] In one embodiment, the first tool may be a handheld punching tool that is adapted to punch a hole in a shell of a bivalve mollusc . For example, the punching tool may include a body having a pointed first end portion and an opposing second end portion that is adapted to be struck by a handheld hammer or, in the case of a spring-loaded punching tool, either a spring-loaded hammer, a tumbler or a striking rod.

[0036] Alternatively, the first tool may include two opposing j aws that are hingedly connected together and which are each connected to a respective divergent handle and wherein urging the two handles together shall cause the aws to clamp about an obj ect, such as a two-part shell, that is located therebetween, and wherein one of the j aws may include a pointed protrusion that is adapted to create a hole in the mollusc' s shell, and wherein the protrusion extends outwardly from the j aw in the general direction of the opposing j aw.

[0037] In still yet another embodiment, the first tool may be a drill having a drill bit that is adapted to create a hole in the mollusc' s shell, such as a manual drill that uses human power to spin a drill bit or a power drill, such as an electrically powered drill .

[0038] Preferably the first tool is a hand-held, battery operated, electric drill having an electric motor that is contained within a housing from which there depends a handle and a drill bit holder, such as a chuck or a lockable bit holder, that is

[0039] tHAG02103de script ion 14 January2026operatively connected to the electric motor via an output shaft and a drill bit having an end portion that may be selectively held tight by said drill bit holder .

[0040] The drill bit may include one or more sharp cutting edges at the bit' s tip which are adapted to scrape and shave away shell fragments as the bit spins and wherein the drill bit may include one or more flutes that run along the operative length of the bit and which are designed to convey at least most of the shell fragments away from the hole .

[0041] The drill bit may further include a shoulder that is axially spaced from the bit' s tip and which extends outwardly away from the flutes . The shoulder in use shall abut against the exterior of the shell and thereby limit the length of the tip of the drill bit that may protrude into the interior of the two-part shell . Preferably the distance from the tip to the shoulder is calculated to ensure that the bit' s cutting edge will not engage the mollusc' s body.

[0042] The drill bit preferably includes an elongate body having a first end portion or shank that is locatable within an axially extending bore of the chuck and which may be selectively retained therein by suitable retaining means, such as a plurality of moveable j aw like members, and an opposing, pointed, second end portion .

[0043] In one embodiment, the shank may be substantially cylindrical in shape . However, in other embodiments the shank may include one or more substantially flat, longitudinally extending, side walls or faces . For example, the shank may have a hexagonal transverse cross-sectional shape .

[0044] tHAG02103de script ion 14 January2026Preferably the second end portion includes two opposing radial cutting edges that extend radially outwardly away from a common, centrally located, pointed end portion or tip .

[0045] Preferably the drill bit also includes two opposing, winding flutes formed in the body and which each extend longitudinally away from a distal end of a respective one of the radial cutting edges . The opposite end of each flute preferably terminates at a shoulder which is axially spaced from the tip and which extends outwardly away from the body beyond the flutes . Further, each flute may include at least one sharpened edge portion or lip .

[0046] Preferably the drill bit is approximately 30 mm long and wherein the diameter of pointed end portion, including the flutes, lies with the range of 2.00mm and 6.00mm. Preferably the diameter of the pointed end portion is 4.5mm.

[0047] Preferably the diameter of the shoulder is larger than the diameter of the pointed end portion. Where the diameter of the pointed end portion is 4.5mm, preferably the diameter of the shoulder is approximately 6.5mm.

[0048] Preferably the axial distance separating the tip and the shoulder lies within the range of 2.00mm and 8.00mm. Preferably the distance separating the tip and the shoulder is approximately 6.00mm.

[0049] Further, the angle formed at the tip where the two cutting edges meet may be between 11 degrees and 135 degrees . However, preferably the tip angle is 120 degrees .

[0050] Preferably, when shucking an oyster according to the present method, the bottom shell is either held in the palm of a user' s

[0051] tHAG02103de script ion 14 January2026hand or supported on a solid surface, such as a table top, such that the top shell is facing generally upward and wherein a hole is formed in the top shell adj acent the adductor muscle using a suitable tool or implement, such as an electrically powered drill .

[0052] When the oyster is in this position, it will be appreciated that the body of the oyster will be floating in oyster liquor that is largely contained in the bottom shell . Consequently, after having cut a hole in the top shell, should the tip of the drill bit make contact with the oyster' s body, it is believed that the oyster liquor will allow the oyster' s body to move out of the way of the approaching drill bit thereby minimizing the likelihood of the drill bit tearing the oyster' s body.

[0053] Because the bottom shell is more curved than the top shell, if the drill bit is used to create a hole in the bottom shell as opposed to the top shell, conceivably the axial distance separating the tip of the drill bit and the shoulder will need to be potentially greater than as described above . Accordingly, in some embodiments, the length separating the tip and the shoulder may be configured so as to encourage the user to create the hole in the top shell and / or to prevent the user from creating the hole in the bottom shell .

[0054] However, the present method is not limited to creating a hole in the top shell . For example, if the hole is created in the bottom shell, after having severed the portion of the adductor muscle that is attached to the bottom shell using the cutting tool and having prised the two shells apart using the third tool, the oyster body may be presented to a consumer still attached to the top shell by the adductor muscle and wherein the top shell may crudely resemble a plate .

[0055] tHAG02103de script ion 14 January! 026The handle may include an internal cavity which is open at one end and wherein the opening may be selectively closed by a cover . The cavity may be adapted to store therein the second tool and / or the lever and / or the drill bit .

[0056] The housing may also include one or more recesses that are adapted to receive and retain therein the drill bit . For example, the recess may be elongate and may generally resemble the shape of the drill bit . Further, the recess may include one or more resilient protrusions that extend outwardly from one or more walls of the recess and wherein the one or more resilient protrusions are adapted to releasably engage the drill bit so as to retain it in the recess .

[0057] Where a drill bit is used to create the opening in the shell, the opening in the first or second shell will have a substantially circular transverse cross sectional shape and wherein preferably the centre of the opening is located between the area of shell to which the adductor muscle is connected and a longitudinal axis of the shell .

[0058] In the case of the bottom shell, the longitudinal axis generally extends between the umbo and the opposing curved end of the shell and, when looking at the internal side of the bottom shell, it has been observed that the adductor muscle is generally connected to the bottom shell just above a transverse axis that bisects the longitudinal axis and generally to the right of the longitudinal axis . That is to say, when looking at the internal side of the bottom shell, the adductor muscle is connected to the first quadrant of the bottom shell .

[0059] In the case of the top shell, the longitudinal axis generally extends from a mid-point of the hinge to an opposing curved part

[0060] tHAG02103de script ion 14 January! 026of the shell and, when looking at the internal side of the top shell, it has been observed that the adductor muscle is generally connected to the top shell just above a transverse axis that bisects the longitudinal axis and generally to the left of the longitudinal axis . That is to say, when looking at the internal side of the top shell, the adductor muscle is connected to the fourth quadrant of the top shell .

[0061] It has also been observed that in the case of mature Southern Pacific oysters that are between one and three years old, and which are commonly referred to in the seafood industry in Australia as plate sized oysters, the length of the top shell between the hinge and the opposing curved edge portion is typically between 60mm and 70mm and wherein the width of the top shell in the vicinity of the transverse axis is between 45mm and 55mm. It has also been observed that the adductor muscle generally has a diameter between 10mm and 15mm and wherein the centre of the adductor muscle is generally located midway between the longitudinal axis and the fringe .

[0062] Accordingly, preferably when looking at the external side of the top shell, the centre of the hole will be roughly located on the transverse axis and to the right of the longitudinal axis . More preferably the centre of the hole will be spaced from the longitudinal axis approximately one sixth of the width of the transverse axis .

[0063] Alternatively, in the case of plate sized oysters, the centre of the hole may be located on the transverse axis approximately 16 mm from the fringe .

[0064] The cutter may include a body that extends outwardly away from the second end portion and wherein the body may be generally

[0065] tHAG02103de script ion 14 January! 026perpendicular to the longitudinal axis of the first end portion or a longitudinal axis of the handle .

[0066] The body may be flat or substantially flat and may include a distal end portion that is spaced from the second end portion of the stem and wherein the distal end portion may include a sharp tip . However, in the preferred embodiment the distal end portion includes a blunt or generally rounded tip .

[0067] The body may include opposing elongate edge portions and wherein at least one of these edge portions may include cutting means that extends along all or at least much of the length of at least one edge portion of the body.

[0068] In one embodiment, the cutting means may consist of a sharpened edge portion of the body. However, in other embodiments, the cutting means may include a plurality of teeth and wherein each of the teeth may include a point and one or more sharp edge portions that trail away from said point .

[0069] Assuming the opening formed in the shell has a substantially circular transverse cross section and wherein the opening lies generally between the longitudinal axis of the shell and the generally circular shaped area of the shell to which the adductor muscle is attached, preferably the longitudinal axis of the opening and the longitudinal axis of the second end portion are substantially coaxial and wherein the length of the body is approximately the same as, or slightly less than, the distance separating the centre of the opening and the edge or fringe of the shell to right thereof . In other words, preferably the length of the body is approximately two thirds of the maximum width of the shell, namely the maximum distance separating the opposing left and right edge portions of the shell .

[0070] tHAG02103de script ion 14 January2026The adductor muscle may be severed from the shell by rotating the body of the second tool through an arc measuring approximately 80 degrees to 145 degrees, commencing from where the cutting means first engages the adductor muscle . However, for the sake of simplicity, and to ensure that the adductor muscle is completely severed, preferably the body of the second tool is rotated through an angle of 360 degrees .

[0071] The lever may resemble a knife and may include a handle and a cutting edge, and wherein the pointed end portion may be used to prise open the two-part shell while the cutting edge may be used to sever the adductor muscle that is still connected to one of the two shells .

[0072] In another aspect, this invention relates to a drill bit for use in shucking a bivalve mollusc of the type having a body enclosed within a two-part shell comprising a first shell and a second shell each having a peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge, and wherein the body includes at least one adductor muscle having a first end that is connected to the first shell and a second end that is connected to the second shell, said drill bit being adapted to create a hole in one of said shells adj acent the adductor muscle while preferably also avoiding contact with the mollusc' s body, said drill bit including :

[0073] an elongate body having a longitudinal axis, said body having a first end portion and an opposing second end portion, and wherein said first end portion is locatable within a chuck of a drill, and wherein said second end portion includes a pointed tip and at least two opposing radial cutting edges that extend radially outwardly from said tip, and

[0074] tHAG02103de script ion 14 January! 026at least two opposing winding flutes formed in said body and wherein each of said flutes extends longitudinally away from a distal end of a respective one of said radial cutting edges and wherein the opposite end of each of said flutes terminates as a shoulder which extends outwardly from said body beyond said flutes, each of said flutes having at least one sharpened edge portion .

[0075] In use, it is envisaged that the shoulder will engage an outer portion of the shell and wherein the maximum depth that the tip may extend into the confines of the mollusc is limited by the axial spacing between the tip and the shoulder . Preferably the longitudinal distance separating the tip and the shoulder will be sufficient to ensure that a hole is created in the shell but wherein the tip will not interfere with the mollusc' s body.

[0076] Preferably the drill bit is approximately 30 mm long and wherein the diameter of pointed end portion, including the flutes, lies with the range of 2.00mm and 6.00mm. Preferably the diameter of the pointed end portion is 4.5mm.

[0077] Preferably the diameter of the shoulder is larger than the diameter of the pointed end portion. Where the diameter of the pointed end portion is 4.5mm, preferably the diameter of the shoulder is approximately 6.5mm.

[0078] Preferably the axial distance separating the tip and the shoulder lies within the range of 2.00mm and 8.00mm. Preferably the distance separating the tip and the shoulder is approximately 6.00mm.

[0079] tHAG02103de script ion 14 January2026Further, the angle formed at the tip where the two cutting edges meet may be between 110 degrees and 135 degrees . However, preferably the tip angle is 120 degrees .

[0080] In still yet another aspect, this invention relates to a tool, namely an adductor cutter, for use in shucking bivalve molluscs of the type having a body enclosed within a two-part shell comprising a first shell and a second shell each having a peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge, and wherein the body includes at least one adductor muscle having a first end that is connected to the first shell and a second end that is connected to the second shell, and wherein one of the shells includes a hole that has been created therein and wherein the hole is located adj acent one end of the adductor muscle, said adductor cutter including:

[0081] an elongate stem having a first end portion and an opposing second end portion, said first end portion having a longitudinal axis ,

[0082] a handle that is connected to said first end portion; a blade that is connected to said second end portion and which extends outwardly away from said second end portion in a direction that is generally perpendicular to said longitudinal axis, said blade having a tip that is remote from said second end portion and at least one cutting means that extends at least partway between said tip and said second end portion.

[0083] Preferably the blade includes first and second cutting means located on opposite edge portions of the blade .

[0084] Preferably the cutting means includes a sharpened edge portion of the blade .

[0085] tHAG02103de script ion 14 January2026Preferably the tip is rounded or blunt .

[0086] Preferably the size and shape of the blade will permit the blade to be extended through the hole in the shell .

[0087] In one embodiment, the stem may include at least one bend and wherein said second end portion as a consequence is offset from said longitudinal axis . Where the adductor tool is housed within a cavity, it is envisaged that the inclusion of at least one bend in the stem will reduce the volume of the cavity required for the storage of the tool .

[0088] In order that this invention may be more easily understood and put into practical effect, reference will now be made to the accompanying drawings wherein:

[0089] FIG. 1 is a side pictorial view of a typical oyster that includes a two-part shell comprising a cup like bottom shell and a substantially flat top shell;

[0090] Fig. 2 is a top view of the oyster shown in figure 1 ;

[0091] Fig. 3 is a top view of the top shell shown in figure 1, including a method according to the present invention for determining the location of a hole to be made in the top shell adj acent the oyster' s adductor muscle;

[0092] Fig. 4 is an internal top view of the top shell of the oyster shown in figure 1 ;

[0093] Fig. 5 is a top view of the oyster shown in figure 1 but wherein the top shell has been removed to reveal the soft fleshy body of the oyster contained within the bottom shell ;

[0094] Fig. 6 is a right side view of an electric drill that has been constructed in accordance with the present invention; Fig. 7 is a left side view of the electric drill that is shown in figure 6;

[0095] tHAG02103de script ion 14 January2026Fig. 8 is a schematic cross-sectional side view of the electric drill;

[0096] Fig. 9 is a side view of an adductor cutter that has been constructed in accordance with the present invention;

[0097] Fig. 10 is a side view of a knife or lever;

[0098] Fig. 11 is a side view of a drill bit that has been constructed in accordance with the present invention, and Fig. 12 is a top view showing a method of cutting the adductor muscle of the oyster which is shown in figure 1 using the adductor cutter that is shown in figure 9.

[0099] Figure 1 shows a typical bivalve mollusc, such as an oyster 10 having a soft body 11 that is enclosed within a rough, generally irregular shaped, two-part shell 12 comprising a bottom shell or left valve 13, that resembles an open topped receptacle or cup, and a substantially flat top shell or right valve 14.

[0100] The peripheral shapes of the bottom and top shells generally compliment each other and wherein when the two shells are in their closed position, as shown in figure 1, the ragged, often sharp, peripheral edge portion or fringe 15 of the top shell 14 is often located behind the peripheral edge portion or fringe 16 of the bottom shell 13.

[0101] The top and bottom shells 14 and 13 respectively are connected by a hinge 17 that is located near the pointed end 18 of the bottom shell and adj acent a conical shaped structure known as the umbo 19.

[0102] The oyster' s body 11 includes a muscle 20, commonly referred to as the adductor muscle, which runs through the oyster' s body, and which includes a first end portion 21 that is attached to the interior face of the top shell 14 at 22 and a second end

[0103] tHAG02103de script ion 14 January2026portion, (not shown) , that is attached to the interior of the bottom shell 13. When the adductor muscle contracts, the top shell 14 will tightly close the receptacle of the bottom shell 13 such that there will be very little if any gap between the fringe 15 and the fringe 16.

[0104] To minimize the risk of a person injuring themselves when shucking an oyster, the inventor has developed a method for shucking oysters which involves creating a hole 25 in the top shell 14 adj acent to the portion 22 of the shell to which the first end portion 21 of the adductor muscle 20 is attached, (shown in dotted outline in figure 3) .

[0105] Further, for the purpose of creating the hole 25, the inventor has developed a first tool in the form of a hand-held, battery powered, electric drill 30 that includes an electric motor 31 which is operably connected to a rechargeable battery 32 and wherein the electric drill also includes control means, including a printed circuit board 33, that is operably connected to both the motor and the battery for controlling the motor current and the battery recharging system. The printed circuit board 33 may also manage the speed of the motor, battery protection and power efficiency.

[0106] The electric drill 30 also includes a drill bit holder 34 for holding a drill bit . In one embodiment, the drill bit holder 34 may include a chuck. However, in other embodiments, the drill bit holder may include a quick release drill bit holder, a lockable bit holder or a magnetic drill bit holder .

[0107] The drill bit holder 34 is operably connected to the motor 31 by an output shaft 35 such that rotation of the output shaft, which is driven by the motor 31, shall cause the drill bit holder

[0108] tHAG02103de script ion 14 January202634 to rotate . The drill bit holder 34 includes a centrally located blind bore 35a equipped with a spring loaded clamping mechanism, not shown, for selectively holding a shank of a drill bit securely when located in the bore .

[0109] The motor 31, battery 32 and printed circuit board 33 are all housed within a generally cylindrically shaped motor housing 36 of a housing 37 that is made from a suitable plastics material .

[0110] The housing 37 also includes a hollow handle or grip 38 that is attached to, and which extends away from, one end of the motor housing 36.

[0111] The handle 38 includes a trigger 39 that is located at the front of the handle, and which is covered by a waterproof rubber seal 40. The trigger 39 is operably connected to the printed circuit board 33 and when pressed will actuate the motor 31, and wherein the speed at which the output shaft rotates may be selectively controlled by the extent by which the trigger is pressed. For example, the more the trigger is pressed, the faster the motor will run.

[0112] The handle 38 also includes an internal cavity 40 that includes an access opening 41 located in the bottom or free end 42 of the handle and wherein the opening 41 is selectively closed by a lid 43 that is hingedly attached to the handle by a hinge 44. The cavity 40 is adapted to receive and store a second tool or adductor cutter 50, for severing the adductor muscle adj acent to where it is attached to the top shell 14, and a lever 51, for prising the curved ends of the two shells 13 and 14 apart,

[0113] The motor housing 36 includes at least one external, elongate, recess 52 that is formed in the housing and a magnet, (not

[0114] tHAG02103de script ion 14 January2026shown) , which is located inside the motor housing and behind the recess 52. The recess 52 is adapted to receive a drill bit 53 which is retained in the recess by magnetic attraction to the magnet . The drill bit recess 52 has two opposing elongate side walls 54 that are adapted to engage, or nearly engage, the drill bit 53 and wherein the recess further includes a finger recess 55 located partway along one of the side walls 54 to enable a user to use one of their fingers to remove the drill bit from the recess .

[0115] The drill bit 53 includes an elongate body 60 having a first end portion or shank 61 that is locatable in the bore of the chuck 34 and an opposing, substantially cylindrical shaped, second end portion or working end 62 for cutting or grinding a hole in the top shell 14 .

[0116] The working end 62 includes a centrally positioned, pointed, end or tip 63 and two radial cutting edges 64 that radiate away from the tip, and wherein the exterior angle between the two radial cutting edges, which is commonly referred to as the tip angle, is approximately 120 degrees, and wherein the diameter of the working end is approximately 4.5mm.

[0117] The working end 62 also includes two winding side flutes 65 formed in the side wall of the working end and wherein each flute includes one winding cutting edge 68 which extends from an outer edge of a respective radial cutting edge 64 to a shoulder 66 that is axially spaced approximately 6mm from the tip 63.

[0118] The shank 61 has a generally hexagonal transverse cross-section shape along much of its length and wherein the shank includes a transverse circumferential groove 67 having a curved continuous

[0119] tHAG02103de script ion 14 January 026side wall that in use is adapted to engage a clamping mechanism associated with the drill bit holder 34.

[0120] The circumradius of the shank is approximately 3.25mm and wherein the length of the shank from its free end to the shoulder is approximately 30mm. The width of the groove is approximately 5mm and wherein the groove is spaced approximately 6mm from the free end of the shank 61.

[0121] The adductor cutter 50 includes an elongate, rigid or substantially rigid, stem 70 having a first end portion 71 to which a there is attached a generally cylindrically shaped handle 72, and an opposing second end portion 73 to which there is connected cutting means 74. Preferably the longitudinal axis of the first end portion 71 and the longitudinal axis of the handle 72 are coaxial or substantially coaxial . Preferably the stem 70 has a substantially circular transverse cross-sectional shape and a diameter in the range of 2mm to 4mm and more preferably 3mm.

[0122] The stem 70 includes a bend 75, part way along its length, and wherein, because of the inclusion of this bend, the second end portion 73 is offset from the first end portion and the longitudinal axis of the handle .

[0123] The cutting means 74 resembles a blade 76 that extends outwardly away from the second end portion 73 and wherein the blade 76 is substantially perpendicular to the longitudinal axis of the first end portion 71 and the longitudinal axis of the handle 72.

[0124] The blade 76 is substantially flat and includes a distal end portion 77 that is spaced from the longitudinal axis of the second end portion 73 and wherein the distal end portion includes

[0125] tHAG02103de script ion 14 January2026a blunt or generally rounded tip 78. Preferably, the distance separating the tip 78 from the longitudinal axis is in the range of 10mm and 16mm and is more preferably 14mm.

[0126] The blade 76 includes two opposing sharpened edge portions 79 that extend along all or at least much of the length of the blade, namely from where the second end portion 73 is connected to the body to the tip 78.

[0127] The free end of the handle 72 includes a notch or finger recess 80 .

[0128] It is envisaged that the stem 70 and the blade 76 may be made from a suitable stainless steel, while the handle 72 may be made from a suitable plastics material .

[0129] The third tool or lever 51 resembles a knife and includes a handle 81 and a substantially flat blade 82 that is attached to the handle . The blade 82 includes a pointed tip 83 that is remote from the handle 81 and two opposing cutting edges 84 that each extend from the base or bottom of the handle 81 to the tip 83.

[0130] The free end of the handle 81 includes a notch or finger recess 85.

[0131] When the adductor cutter 50 and the knife 51 are stored in the cavity 40 and the two finger recesses 80 and 85 face each other, there exists a gap large enough that a user may insert at least a finger therein for extracting one or both tools from the cavity .

[0132] It is envisaged that the blade 82 may be made from a suitable stainless steel, while the handle 81 may be made from a suitable plastics material .

[0133] tHAG02103de script ion 14 January2026In order to separate the top shell 14 from the bottom shell 13 and thereby gain access to the body 11 of the oyster which is contained substantially within the bottom shell 13 and surrounded by oyster liquor, it is first necessary to create a hole 25 in the top shell 14 adj acent the portion 22 of the shell to which the free end portion 21 of the adductor muscle 20 is attached .

[0134] In order to make the hole 25 in the top shell 14, the user may either support the bottom shell 13 in the palm of one of their hands such that the top shell 14 is facing upwards or use one of their hands to support the bottom shell on a firm surface, such as a table, in a manner whereby the top shell is facing generally upwards . Next, the user may use a finger to trace an imaginary longitudinal axis 90 and an imaginary transverse axis 91 on the top shell while taking particular care to remember the approximate point at which the two axes intersect .

[0135] The centre of the hole 25 will lie preferably on the transverse axis 91 and to the right of the point at which the axes intersect . Preferably the centre of the hole is spaced from the point at which the axes intersect approximately one sixth of the length of the transverse axis or alternatively, in the case of a mature oyster, such as a Southern Pacific oyster, approximately 16mm from the fringe 15.

[0136] Having determined the approximate position of the centre of the hole 25, the user may then remove the drill bit 53 from the drill bit recess 52 and locate the shank 61 of the drill bit securely in the chuck 34 .

[0137] tHAG02103de script ion 14 January2026The tip 63 of the drill bit 53 is then placed against the surface of the top shell 14 where the user has previously determined the centre of the hole will be and shall, by depressing the trigger 39, actuate the drill' s motor 31 thereby causing the drill bit 53 to rotate . As the drill bit' s cutting edges 64 and 68 rotate they will in turn create the hole 25 and wherein the flutes 65 will convey at least most of the shell grit that is produced away from the hole where it will then collect on the exterior of the shell, generally surrounding the peripheral edge of the hole 25.

[0138] In most instances contact between the shoulder 66 of the drill bit 53 and the exterior of the shell 14 will prevent the tip 63 and the cutting edges 64 from contacting the body 11. However, in the unlikely event that the tip 63 does contact the body 11, the inventor believes that the oyster liquor between the body and the bottom shell will be displaced thereby permitting the body to move out of the away of the advancing working end of the drill bit .

[0139] After removing the drill bit 53 from the hole 25, the user may move the lid 43 from its closed position to an open position that will provide the user with access to the cavity 40 so that the user may remove the adductor cutter 50 and the knife 51 therefrom.

[0140] The blade 76 of the adductor cutter 50 may then be inserted into the hole 25 such that the blade 76 is located adj acent the internal face of the top shell 14 and between the top shell 14 and the body 11. Further, should the blunt end 78 of the blade 76 contact the body 11 of the oyster, the inventor believes that the oyster liquor between the body 11 and the bottom shell 13

[0141] tHAG02103de script ion 14 January2026will be displaced thereby permitting the body 11 to move out of the away of the advancing blade 76 of the adductor cutter 50.

[0142] The user may then rotate the handle 72 of the adductor cutter 50 about the handle' s longitudinal axis, either in a clockwise or anticlockwise direction, as generally indicated by the arrows in figure 12, and whereby either one of the cutting portions 79 will eventually engage the end portion 21 of the adductor muscle 20, and wherein further rotation of the blade will sever the end portion 21 from the portion 22 of the shell 14.

[0143] Having broken the connection between the adductor muscle 20 and the top shell 14, the tip 83 of the knife 51 may then be inserted between the fringe 15 of the top shell 14 and the fringe 16 of the bottom shell 13 the top shell 14 and wherein the blade 82 may be used as a lever to prise the rounded end portions of the two shells 13 and 14 apart, thereby exposing the body 11 of the oyster . Because the adductor muscle 20 is no longer connected to the top shell 14, it will be appreciated that less force will be required to insert the tip 83 between the two shells than was previously required.

[0144] The user may then use their hands to tear the hinge and separate the top shell 14 from the bottom shell 13. Alternatively, either one of the blade' s cutting edges 84 may be used to cut the hinge .

[0145] One of the cutting edges 84 may be then used to sever the connection between the adductor muscle 20 from the bottom shell 13 allowing the body to be removed from the bottom shell and eaten .

[0146] It will be appreciated that the inventor' s method of shucking an oyster, which involves creating a hole in the top shell and

[0147] tHAG02103de script ion 14 January2026using a blade to sever the connection between the adductor muscle significantly reduces the risk of injury.

[0148] While the foregoing description has been given by way of example of the invention, it will be understood that the invention may be embodied in many other forms and all such forms are deemed to fall within the broad scope and ambit of the invention as hereinbefore defined in the appended claims .

[0149] tHAG02103de script ion 14 January2026

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS :

1. A method of shucking bivalve molluscs of the type having a body enclosed within a two-part shell comprising a first shell and a second shell each having a peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge, and wherein the body includes at least one adductor muscle having a first end that is connected to the first shell and a second end that is connected to the second shell, said method including:providing a first tool that is capable of creating an opening in the mollusc' s shell;using the first tool to make an opening in either the first or second shell adj acent the adductor muscle;providing a second tool, or adductor cutter, of the type having a handle at one end and a cutter located at the opposite end and wherein the cutter is capable of severing the adductor muscle, said handle being connected to said cutter by a stem;extending the cutter through the opening such that the cutter is located adj acent a portion of the shell that surrounds the opening;at least partially rotating the handle of the second tool such that the cutter severs the adductor muscle which will in turn enable the peripheral edge portions of the two shells to be easily separated such that there exists a gap therebetween;providing a lever having a first end portion that is adapted for location within the gap and an opposing second end portion that is capable of being used as a handle;locating the first end portion in the gap between the two shells and applying a force to the handle in a direction that is generally perpendicular to a plane generally containing said shells which is at least sufficient to displace one of the shells relative to the other so as to permit removal of the body.tHAG02103claims 14 January20262. A method of shucking bivalve molluscs as claimed in claim 1, wherein the bivalve mollusc is an oyster and wherein the first shell or top shell is substantially flat and wherein the second shell or bottom shell resembles a receptacle, and wherein the oyster' s body is surrounded by oyster liquor .

3. A method of shucking bivalve molluscs as claimed in any one of the preceding claims, wherein the mollusc is supported in a manner whereby the top shell is facing generally upwards .

4. A method of shucking bivalve molluscs as claimed in claim 3, wherein the opening is created in the top shell .

5. A method of shucking bivalve molluscs as claimed in any one of the preceding claims, wherein said first tool is a drill that includes a drill bit that is adapted to create a suitable sized opening in the mollusc' s shell .

6. A method of shucking bivalve molluscs as claimed in claim 5, wherein the opening in the mollusc' s shell will have a substantially circular transverse cross sectional shape and wherein the centre of the opening is located between the area of the shell to which the adductor muscle is connected and a longitudinal axis of the shell which extends generally from a mid-point of the hinge to an opposing curved part of the shell .

7. A method of shucking bivalve molluscs as claimed in claim 6, wherein the drill bit includes one or more sharp cutting edges at the bit' s tip and one or more flutes that run along the operative length of the bit .

8. A method of shucking bivalve molluscs as claimed in claim 7, wherein the drill bit includes a shoulder that is axiallytHAG02103claims 14 January2026spaced from the bit' s tip and which extends outwardly away from the flutes .

9. A method of shucking bivalve molluscs as claimed in claim 8, wherein the distance from the tip to the shoulder is calculated to ensure that the bit' s cutting edge will not engage the mollusc' s body.

10. A method of shucking bivalve molluscs as claimed in any one of the preceding claims, including:supporting the mollusc in a position whereby the top shell is facing generally upward and the hinge is pointing generally at the user,creating the opening in the mollusc' s top shell using the first tool, the opening being located to the right of a longitudinal axis that generally extends from a mid-point of the hinge to an opposing curved part of the shell and either on or just above a transverse axis that bisects the longitudinal axis .

11. A method of shucking bivalve molluscs as claimed in claim 10, wherein the centre of the opening is spaced from the longitudinal axis approximately one sixth of the width of the transverse axis .

12. A method of shucking bivalve molluscs as claimed in claim 10, wherein the centre of the opening is located on the transverse axis approximately 16 mm from the fringe .

13. A method of shucking bivalve molluscs as claimed in any one of the preceding claims, wherein the second tool includes a stem that connects the cutter to the handle and wherein the cutter includes a body that extends outwardly away from the stem and generally perpendicular to a longitudinal axis of the handle .tHAG02103claims 14 January202614. A method of shucking bivalve molluscs as claimed in any one of the preceding claims, wherein the cutter includes a substantially flat body having opposing elongate edge portions and wherein at least one of these edge portions includes cutting means .

15. A method of shucking bivalve molluscs as claimed in claim 14, wherein said cutting means consists of a sharpened edge portion of the body.

16. A method of shucking bivalve molluscs as claimed in 13, wherein the longitudinal axis of the opening and the longitudinal axis of the handle are substantially coaxial and wherein the length of the cutter is approximately the same as, or slightly less than, the distance separating the centre of the opening and the edge or fringe of the shell to the right thereof .

17. A method of shucking bivalve molluscs as claimed in claim 13, wherein the length of the cutter is approximately two thirds of the maximum width of the shell .

18. A method of shucking bivalve molluscs as claimed in claim 5, wherein the drill includes a handle having an internal cavity which is open at one end and wherein the opening is selectively closed by a cover and wherein the cavity is adapted to store therein the second tool and / or the lever and / or the drill bit .

19. A drill bit for use in shucking a bivalve mollusc of the type having a body enclosed within a two-part shell comprising a first shell and a second shell each having a peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge, and wherein the bodytHAG02103claims 14 January2026includes at least one adductor muscle having a first end that is connected to the first shell and a second end that is connected to the second shell, said drill bit being adapted to create a hole in one of said shells adj acent the adductor muscle while preferably also avoiding contact with the mollusc' s body, said drill bit including:an elongate body having a longitudinal axis, said body having a first end portion and an opposing second end portion, and wherein said first end portion is locatable within a drill bit holder of a drill, and wherein said second end portion includes a pointed tip and at least two opposing radial cutting edges that extend radially outwardly from said tip, andat least two opposing winding flutes formed in said body and wherein each of said flutes extends longitudinally away from a distal end of a respective one of said radial cutting edges and wherein the opposite end of each of said flutes terminates as a shoulder which extends outwardly from said body beyond said flutes, each of said flutes having at least one sharpened edge portion .

20. A drill bit for use in shucking a bivalve mollusc as claimed in claim 19, wherein said drill bit includes a shoulder that is axially spaced from the bit' s tip and which extends outwardly away from the flutes .

21. A drill bit for use in shucking a bivalve mollusc as claimed in claim 20, wherein the distance from the tip to the shoulder is calculated to ensure that the bit' s cutting edge will not engage the mollusc' s body.

22. A drill bit for use in shucking a bivalve mollusc as claimed in claim 21, wherein the drill bit is approximately 30 mm longtHAG02103claims 14 January2026and wherein the diameter of pointed end portion, including the flutes, lies with the range of 2.00mm and 6.00mm.

23. A drill bit for use in shucking a bivalve mollusc as claimed in claim 22, wherein the diameter of the pointed end portion is 4 . 5mm.

24. A drill bit for use in shucking a bivalve mollusc as claimed in claim 23, wherein the diameter of the shoulder is approximately 6.5mm.

25. A drill bit for use in shucking a bivalve mollusc as claimed in any one of claims 22 to 24, wherein the axial distance separating the tip and the shoulder lies within the range of 2.00mm and 8.00mm.

26. A drill bit for use in shucking a bivalve mollusc as claimed in any one of claims 22 to 24, wherein the distance separating the tip and the shoulder is approximately 6.00mm.

27. A drill bit for use in shucking a bivalve mollusc as claimed in any one of claims 19 to 26, wherein the angle formed at the tip where the two cutting edges meet is between 110 degrees and 135 degrees .

28. A drill bit for use in shucking a bivalve mollusc as claimed in any one of claims 19 to 26, wherein the angle formed at the tip where the two cutting edges meet is approximately 120 degrees .

29. An adductor cutter, for use in shucking bivalve molluscs of the type having a body enclosed within a two-part shell comprising a first shell and a second shell each having atHAG02103claims 14 January2026peripheral edge portion, said first and second shells being hingedly connected together at one end thereof by a hinge, and wherein the body includes at least one adductor muscle having a first end that is connected to the first shell and a second end that is connected to the second shell, and wherein one of the shells includes a hole that has been created therein and wherein the hole is located adj acent one end of the adductor muscle, said adductor cutter including:an elongate stem having a first end portion and an opposing second end portion, said first end portion having a longitudinal axis ,a handle that is connected to said first end portion; a blade that is connected to said second end portion and which extends outwardly from said second end portion in a direction that is generally perpendicular to said longitudinal axis, said blade having a tip that is remote from said second end portion and at least one cutting means that extends at least partway between said tip and said second end portion.

30. An adductor cutter as claimed in claim 29, wherein said blade includes a substantially flat body having opposing elongate edge portions and wherein at least one of these edge portions includes cutting means .

31. An adductor cutter as claimed in claim 30, wherein said cutting means consists of a sharpened edge portion of said body.tHAG02103claims 14 January2026

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