An apparatus and a method for processing a fish product

Abstract

An apparatus (1) for processing a fish product, the apparatus comprising: - a pressing structure (6) arranged to engage the fish product with an engagement pressure to thereby influence the shape of the fish product; and - a processing structure for processing the fish product while the pressing structure engages the fish product with the engagement pressure. To make the processing more uniform for different fish products, the apparatus comprises an electronic control structure (10) configured to read a deformability parameter representing an ability of the fish product to deform, and to control the pressing structure to engage the fish product with an engagement pressure which depends on the deformability parameter.

Description

[0001] AN APPARATUS AND A METHOD FOR PROCESSING A FISH PRODUCT

[0002] INTRODUCTION

[0003] The present invention relates to processing of fish products such as processing of whole fish or fish fillets.

[0004] BACKGROUND

[0005] In food industry, fish processing typically includes removal of the head and the fish intestines.

[0006] The head is typically removed in a de-capitating apparatus where the fish is gripped near the collar bone, and a knife separates the head from the body close to the collar bone.

[0007] Subsequently, the fish is typically split longitudinally and vertically into two fish fillets and the backbone. Herein, removal of the head is referred to as de-capitating and the subsequent splitting is referred to as filleting . Fish which are typically filleted includes white fish and fish from the Salmonidae family including salmon.

[0008] The spine part of the fish is the part extending upwardly from the backbone to the upper back of the fish. The lateral sides are on opposite sides of the backbone and include the belly part of the fish extending downward from the backbone to the abdomen or belly. The center plane of the fish is a longitudinally extending vertical plane intersecting the middle of the backbone between the two lateral sides and thus the fillets. The fillets are the pieces of meat arising when the fish is split as described above. By definition herein, the thickness of the fish is the dimension from the outer surface of one of the two lateral sides to the opposite one of the two lateral sides, i.e. a horizontal dimension transverse the swimming direction of the fish. Also, by definition herein, the height of the fish is the dimension from the lower surface of belly to the upper surface of the back, i.e. a vertical dimension transverse to the swimming direction of the fish. Also, by definition herein the length of the fish is the dimension from head to tail, i.e. a horizontal dimension parallel to the swimming direction of the fish.

[0009] When separating the fillets from the backbone, the pin bones and potentially also rib bones remain in the fillet. The pin bones are also referred to as nerve bones, and they are typically cut free from the backbone and remain in the fillets. After filleting and after removing any rib bones, it is common to remove these pin bones in devices for automatic deboning. This process is herein referred to as pin boning.

[0010] When removing skin from fish fillets, it is well known to use skinners where the fish fillet slides across a skinning knife which cuts off the skin.

[0011] De-capitating, filleting, and pin boning devices of different kinds exist, e.g., devices for fish in the Salmonidae family such as salmon and trout. Pin boning devices, mentioned as an example, typically work with a roller or press which contacts the fish or the fish fillet and influences the shape during the processing. This may improve the quality of the processing, the speed of the processing, and / or the yield obtained by the processing.

[0012] During pin boning, the bones may be pulled out of the fish fillet while the meat is compressed to thereby raise the pin bones from the surface of the meat.

[0013] During skinning, the fish fillet may be pressed against the surface of the skinner to obtain a more uniform skinning process.

[0014] Automated processing equipment is suitable for fast and identical processing of large amounts of fish products. Typically, however, each fish reacts differently to identical processing, e.g., due to different hardness or stiffness of the meat. Accordingly, the processing result, e.g., the quality, processing speed, and / or the yield may differ between different fish even though the process as such is carried out identically.

[0015] SUMMARY OF THE INVENTION

[0016] It is an object of embodiments of the present invention to provide an improved fish processing apparatus which can provide a more uniform processing of fish products to potentially improve quality, processing speed, and / or yield.

[0017] For this and other objects, the present invention provides an apparatus and a method of processing a fish product according to the independent claims.

[0018] The pressing structure is arranged to press against the surface of the fish product and thereby engage the fish product with an engagement pressure which influences the shape.

[0019] The pressure may e.g. support and keep the shape of the fish product while it is processed. An example is when the pressure maintains a specific shape of the fish product while the processing takes place. If the processing structure includes a knife for filleting the fish product, then the pressing structure may apply a pressure which counteracts the pressure of the knife and thereby maintains the shape of the fish product.

[0020] Alternatively, the engagement pressure may amend the shape of the fish product when it is processed, e.g., to obtain a more homogenous shape of a plurality of fish products each having individual shape. An example of this is when the pressure changes the thickness of the fish product while the processing takes place.

[0021] The pressing may particularly be considered as pressing against the meat of the fish product, and it may particularly be considered as pressing against the exposed meat, i.e. meat which is not protected by fish skin etc. Accordingly, this is different from pressing e.g. against entrails during gutting of the fish etc.

[0022] When the processing depends on the deformability parameter, it allows the application of as much pressure as possible without destroying typically vulnerable exposed meat of a fish product such as the exposed meat of the inner surface of a fish fillet. That allows optimal processing without destroying the meat and therefore potentially increases the quality of the processed fish product and potentially increases the processing speed.

[0023] The processing structure may particularly be a cutting structure including a knife penetrating the fish product, or the processing structure may be configured for removing pin bones.

[0024] Even though pressing against the surface during processing may stabilize the shape or amend the shape of the fish product and thereby improve the ability to process the fish product, the pressing against the surface may also damage the fish product, e.g. leaving pressure marks in the meat or otherwise reducing the appearance or quality of the fish product.

[0025] Since the apparatus comprises an electronic control structure which can control the pressing structure based on the deformability parameter and thereby engage the fish product with an engagement pressure which depends on the deformability of the fish product in question, the pressure against the fish product may be applied differently depending on the ability of the fish product to deform or withstand the pressure.

[0026] Accordingly, those fish products which are easily deformed, e.g., due to a soft and elastic structure, may only be pressed with a relatively low force, whereas fish products being more rigid or hard and therefore less easily deformed, could be pressed with a relatively high force. Less stress leads to a better fish product without gaping and downgrading. Accordingly, the invention improves the ability to process the fish product while protecting the fish product against excessive and potentially damaging pressures which may increase the quality.

[0027] The deformability parameter could be determined for a batch of fish products or individually for each fish product being processed. In practice, the deformability parameter may depend on various factors including temperature, humidity, duration since slaughter of the fish, geographical location of the fish, and transportation etc., it may be an object to measure the deformability parameter just before the processing of the fish product.

[0028] The term "fish product" when used herein denotes e.g., a whole fish, a fish with or without tail and / or intestines, a fish fillet, and / or other parts of a fish. Particularly, the fish product could be a fish or a fish fillet from fish of the Salmonidae family, and particularly, it may exclude Thunnus or other genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. The fish product may be a fish or fish fillet with a length in the range of 25-125 cm.

[0029] The term "deformability" when used herein denotes how easy it is to deform the fish product, i.e. how dense the fish product is, i.e., it could alternatively be referred to as a density even though it is not necessarily an exact measure of weight per volume unit etc. but a more general indication of denseness and therefore typically a measure of hardness and / or elasticity. Accordingly, the corresponding deformability parameter does not necessarily refer to a measure of weight per cubic unit or a shore hardness or a coefficient of elasticity etc., but simply a number defining how easy it is to deform the fish product relative to other fish products in the row of fish products being processed. Accordingly, the term deformability could, alternatively, be density, the term deformability parameter could be density parameter, the term deformability meter structure could be a density meter structure, and the term deformability sensor could be density sensor.

[0030] The deformability parameter of the fish product, dF, could be provided by the following equation which herein is one example of a deformability parameter equation: dF=d / mp / dP where: dimp is the impact, i.e., the degree of deformation of the fish product. This could e.g. be a change in thickness obtained when changing between different pressures or it could be a penetration depth when penetrating an element into the fish product, dimp could be measured e.g., in millimeter (mm). dP is the change in pressure or force against the fish product providing the impact. For a specific structure being pressed against the fish product, dP could be measured in Newton (N).

[0031] The deformability parameter may depend on further parameters like the time of the day, the temperature, the air-humidity, the relative air-pressure etc. The electronic control structure may take such parameters into consideration when controlling the pressing structure based on the deformability parameters. In one example, the electronic control structure utilizes a formula defining a control parameter for the pressing structure as a function of the deformability parameter and one of the mentioned parameters. If the parameter is temperature, then the result would be that temperature variations would introduce variations in the control parameter for the pressing structure etc.

[0032] I.e., the deformability parameter expresses the impact of the pressure, e.g., the change in the thickness of the fish product when the fish product is compressed.

[0033] In one embodiment, filleting, defined as splitting the fish into two fish fillets and the backbone, is excluded from the scope, i.e. the processing could be any kind of processing except filleting and / or gutting.

[0034] In one embodiment, it should be understood that the following features in combination are excluded :

[0035] An apparatus for filleting a fish, the apparatus comprising :

[0036] - a conveyor for conveying the fish in a conveying direction with a backbone of the fish following a center plane of the apparatus and with lateral sides of the fish on opposite sides of the center plane;

[0037] - a cutting structure configured for filleting the fish;

[0038] - a shaping structure arranged to engage the lateral sides to obtain a desired shape of the lateral sides; - an electronic control structure configured to read a deformability parameter representing an ability of the fish to deform, and to control the shaping structure to engage the lateral sides with a pressure depending on the deformability parameter during filleting of the fish.

[0039] In one embodiment, it should be understood that the following combination of method steps are excluded :

[0040] A method of filleting a fish wherein a plurality of fish is conveyed in a row of fish following a conveying direction with a backbone of the fish following a virtual center plane of the apparatus and with lateral sides of the fish being on opposite sides of the center plane; and wherein the lateral sides are urged towards each other and / or away from each other with a force determined based on the ability of the fish to deform while the lateral sides are released from the backbone and the ribs.

[0041] Moreover, a pressing structure configured to apply pressure against entrails, e.g. during gutting may not be seen as part of the invention.

[0042] These above apparatuses, features, and method steps may therefore in one series of embodiments be seen as not being within the scope of the independent claims.

[0043] In contrast to the above mentioned examples of filleting and gutting, the apparatus and method of the independent claims may concern a pressing structure configured for pressing against an exposed meat surface of the fish product with the engagement pressure to thereby influence the shape of the meat of the fish product.

[0044] Also, the deformability meter structure may be configured to apply the measuring pressure to an exposed meat surface of the fish product and to determine the deformation of the exposed meat surface of the fish product obtained by the pressure.

[0045] This is in contrast to the filleting and gutting where pressure may be applied to a skin surface where the meat is not exposed, or applied to entrails.

[0046] The term "conveyor" may include any means for conveying a fish product, particularly a belt conveyor, e.g., with an endless belt. In a first series of embodiments, the apparatus according to the invention defines a pin boner. In this series of embodiments, the apparatus comprises a conveyor for conveying in a downstream direction, a stream of the fish products, particularly in the form of fish fillets and the first series of embodiments will be explained in the following relative to fish fillets. Each fish fillet has a lateral outer side and a lateral inner side. In this first line of embodiments, the pressing structure is arranged to compress a portion of the lateral inner surface which constitutes an exposed meat surface and which contains pin bones. This portion is herein referred to as a pin bone portion.

[0047] This compression of the pin bone portion could be done by pressing against the inner or outer lateral surface, i.e. the area of the lateral inner or outer surface where pin bones could be found.

[0048] The compression could be made with a plate shaped or a comb shaped element or a roll, e.g., having projecting pins engaging the fish fillet pointwise or having a lattice structure, e.g., having a surface made from a mesh.

[0049] The engagement pressure could be applied while the fish fillet is conveyed, and the intention is to force an end portion of the pin bones out of the lateral inner side of the fish fillet such that the end portion projects from the surface of the meat.

[0050] In the first series of embodiments, the processing structure forms a pin boning structure configured for pin boning the lateral inner side while the fish fillet is conveyed and while the pin bone portion and thus an exposed meat surface of the fish product is compressed by the pressing structure.

[0051] The pressing structure may either compress the pin bone portion with a fixed engagement pressure throughout the fish fillet, or with an engagement pressure which varies in a length direction of the fish fillet.

[0052] Such a pin bone removal apparatus may allow a more efficient removing of pin bones in fish fillets, such as salmon and trout fillets, and particularly it may better protect the fish fillet against excessive compression and potential damage while still releasing the ends of the pin bones for an efficient pin bone removal.

[0053] Since the engagement pressure depends on the deformability parameter, sufficient pressure may be applied to raise the pin bones out of the meat while avoiding excessive pressures potentially damaging the meat.

[0054] The pin boning structure may be configured for pin boning the lateral inner side while the fish fillet is conveyed on the conveyor with the lateral inner side facing upwards and away from the conveyor. The pin boning structure could be a pin boning roll arranged to roll with a roll pressure against the pin bone portion. Such pin boning rolls are known in the art.

[0055] In one embodiment, the pin boning roll could form part of a single unit including the pressing structure and the pin boning roll. Accordingly, the pin boning roll may form at least a part of the pressing structure and the roll pressure may depend on the engagement pressure or it may be identical to the engagement pressure.

[0056] Such a single unit may particularly hold the pressing structure a bit closer to the fish fillet than the pin boning roll such that the pressure is primarily, or only, applied by the pressing structure and not by the pin boning roll.

[0057] The difference in distance between the pressing structure and the fish fillet and the pin boning roll and the fish fillet, respectively, could be adjustable by adjustment of the position of the pin boning roll relative to the pressing structure. The adjustment may be static, i.e. the same adjustment is used for a batch of fish fillet, or the adjustment may be dynamic, i.e., changed depending on a measure of the fish fillet. The measure could be the deformability parameter, or a dimension such as thickness, or length of the fish fillet. The adjustment may depend on the engagement pressure.

[0058] The apparatus may comprise a bone raising structure arranged upstream the pin boning roll. The bone raising structure may be constituted by a mesh or steel grid sliding over the fish fillet and thereby raising the pin bones upon contact with the mesh or grid. The bone raising structure may alternatively be constituted by a roll, e.g. a roll rotating against the direction of the fish fillet on the conveyor and thereby raising pin bones sticking out of the lateral inner side.

[0059] In a second series of embodiments, the apparatus defines a skinner for removing skin from the lateral outer side of the fish product, in this case, the fish product may particularly be fish fillets and the second series of embodiments will be explained in the following relative to fish fillets. In this series of embodiments, the apparatus comprises a conveyor for conveying a stream of fish products in the form of fish fillets with a lateral outer side of each fish fillet towards a surface of the conveyor and an opposite lateral inner side of each fish fillet facing away from the conveyor surface.

[0060] The pressing structure is arranged to press the lateral outer side of a fish fillet towards the surface of the conveyor while the fish fillet is conveyed, particularly by applying the engagement pressure against the exposed meat surface of the inner side of the fish fillet. In the second series of embodiments, the processing structure forms a skinning structure configured for removing skin from the lateral outer side while the fish fillet is conveyed and while the portion of the lateral inner side of the fish fillet is compressed by the pressing structure. The skinning structure may comprise a knife edge elevated a short distance above the surface of the conveyor to cut or scrape off the skin or part of the skin when the fillet travels across the knife edge.

[0061] Due to the engagement pressure which depends on the deformability parameter, the fish fillets can be pressed towards the conveyor surface while the knife edge cuts the skin away, and the pressure may be sufficiently high to ensure a good skinning quality and still not destroying the meat.

[0062] The pressing structure may comprise pressing rollers with variable diameter and arranged to press with different force across the fish fillet. This supports different cutting depth across the fish fillet.

[0063] The electronic control structure may be configured to control the pressing structure to engage the fish fillet with an engagement pressure which varies for different parts of the fish fillet. In one embodiment, the pressure varies across the height of the fish fillet and depends on the deformability parameter, in another embodiment, the pressure varies along the length of the fish fillet and depends on the deformability parameter, and in another embodiment the pressure varies both along the length of the fish fillet and across the height of the fish fillet and depends on the deformability parameter.

[0064] In a third series of embodiments, the apparatus defines a de-capitating apparatus configured for processing fish products, particularly in the form of whole fish with or without tail and / or intestines, i.e. to cut off the head of a fish. In the following, the third series of embodiments is explained relative to gutted, whole fish.

[0065] The de-capitating apparatus comprises a gripper arranged to grip the fish. In the third series of embodiments, the pressing structure forms part of the gripper which is arranged to compress a gripped portion of the fish with the engagement pressure.

[0066] The processing structure forms a de-capitating structure configured for removing the head of the fish while the fish is compressed by the gripper.

[0067] Since the gripper presses the fish with the engagement pressure which depends on the deformability parameter, e.g., a deformability parameter of that specific fish, the fish may be deformed consistently, i.e., each fish in series of fish may be compressed based on the engagement pressure such that the compression becomes more uniform for different fish having different deformability. That enables a more uniform de-capitation with less loss of meat and less quality problems where parts of the head remain on the fish body after the decapitation.

[0068] The gripper may comprise a row of individual claws arranged to grip the fish. In the row, one of the claws could be referred to as a collar claw. This claw terminates one end of the row, and it is configured to grip very close to the collar bone of the fish.

[0069] The compression of the gripped portion of the fish with the engagement pressure is caused by the collar claw, and the processing structure is configured to cut the head off very close to the collar claw, e.g. in a V-shaped cut extending close to the collar claw.

[0070] When the collar claw grips with the engagement pressure, i.e. a pressure adjusted based on the deformability of the fish, it may place different fish more uniformly relative to the knives which cut off the head, and that can improve the quality and yield since the knives can cut very close to the collar bone still leaving the collar bone on the head part of the fish.

[0071] The following disclosure relates to any apparatus and method according to the independent claims, including but not limited to the first, second, and third series of embodiments.

[0072] The apparatus may comprise a data interface configured to communicate the deformability parameter of the fish product between an external data interface. The communication could be data communication between the apparatus and a previous fish processing device in a factory, or the communication could be with a user interface where the operator can enter a deformability parameter. In this case, the deformability parameter could be keyed in by a human operator, or it could be received from processing equipment located upstream the apparatus in a series of fish product processing equipment.

[0073] The fish product may change the deformability parameter during the period following the slaughtering of the fish, particularly because of the pre and post rigor states. The electronic control structure may be configured to translate a certain duration after slaughtering into a deformability parameter. Such a feature may involve an empirical model included in the control structure and configured, e.g. based on a selection of a specific kind of fish from a library and a duration after slaughter, to determine an estimate of the deformability parameter. Alternatively, or additionally, the apparatus may comprise a deformability meter structure arranged upstream the pressing structure and configured to determine the deformability parameter of the fish product before the fish product reaches the pressing structure.

[0074] The deformability meter structure may comprise one or more deformability sensors. The deformability sensor could be a structure which is pressed against the fish product by any suitable mechanism such as magnetism, e.g., by an electrical motor, or by pneumatic or hydraulic forces. The deformability meter structure thereby applies a measuring pressure to the fish. The deformability sensor could have any surface shape towards the fish product, e.g., a flat or spherical shape facing the fish product. The measuring pressure may be applied to an exposed meat surface of the fish product, e.g. an inner surface of a fish fillet where the meat is not protected by skin or entrails etc.

[0075] The deformability meter structure may comprise several deformability sensors arranged either at the same location of the conveyor, or placed along the conveyor, and each deformability sensor may be arranged to apply the pressure at different locations on the fish product. This could e.g. be near the head end, near the tail end, at the thickest point on the fish product, or elsewhere on the fish product.

[0076] Particularly, the deformability meter structure may provide an electrical deformability signal, e.g., a digital signal, e.g., communicated by cable or wirelessly to an electronic controller.

[0077] The deformability meter structure may comprise at least two deformability sensors both configured to measure the position of the fish product, such as the exact location in the processing apparatus and hereby the location of the fish through the apparatus may be determined during the processing. At least one of the deformability sensors could be configured to apply a measuring pressure to the fish product while measuring the position of the fish product.

[0078] The two deformability sensors could be located at a distance from each other in the conveying direction.

[0079] A deformability sensor could be a sensor having a contact element by which the surface of the fish product is contacted and optionally compressed. During this process, the ratio between the contact pressure and the deformation of the fish product is recorded and converted into the deformability parameter. In one example, the deformability parameter could be a scale from a lowest value pertaining to a low deformability to a highest value pertaining to a high deformability, e.g., a digit from 1 to 10. The two deformability sensors may be configured to apply different measuring pressures to the fish product. In one example, the measuring pressure is applied from an outer side of the fish product, e.g., perpendicular to the length direction and / or perpendicular to a height direction, and in another example, the measuring pressure is applied from an inner side of the fish product, e.g., perpendicular to the length direction and / or perpendicular to a height direction. The deformability sensors may also apply the measuring pressure at different locations of the fish product.

[0080] At least one of the at least two deformability sensors could be arranged to apply the measuring pressure at a location of the fish product where the distance from the center plane to the lateral sides of the fish product is larger than at any other location of the fish product. This location may e.g. be where the maximum thickness of the fish product is found.

[0081] At least one of the at least two deformability sensors could be configured to provide an additional measure of the fish product. In one example, it is constituted by, or integrated into a sensor which measures a dimension, e.g., the thickness of the fish product, or a sensor which registers the position of the fish product when it travels in the conveying direction.

[0082] The deformability meter structure may e.g., be configured to calculate an average value from different deformability sensors, or it could be configured to calculate a difference between measurements of the at least two deformability sensors. In this case, the actual deformability parameter could be based on said average or said difference. Alternatively, the deformability parameter is calculated based on a transfer function defining translation of data from the deformability sensors to a deformability parameter.

[0083] The deformability parameter may exclusively represent ability of the fish product to deform elastically and the deformability meter structure may therefore be configured to apply the measuring pressure to the fish product such that the measuring pressure elastically deforms the fish product without plastically deforming the fish product.

[0084] The deformability sensors may be configured for determining the deformability parameter for a specific spot on the fish product. The spot could define a narrow point on the fish product or a line over a surface of the fish product. The deformability sensors could be configured for defining a plurality of such points e.g., along lines or in a matrix spread over the surface of the fish product. The plurality of points spread over the surface of the fish product will provide a more exact image of the deformability.

[0085] The pin boner of the first series of embodiments may be combined with the skinner of the second series of embodiments to thereby process fish fillets by first pin boning the fillets and subsequently skinning the fish fillets, alternatively skinning the fish fillets before pin boning them.

[0086] In a second aspect, the invention provides a method for processing fish products. The method comprises:

[0087] - pressing a pressing structure against the fish product with an engagement pressure; and

[0088] - processing the fish product while the shape is influenced by the engagement pressure; wherein the engagement pressure is determined by reading a deformability parameter representing an ability of the fish product to deform and determining the engagement pressure based on the deformability parameter, to thereby process the fish product.

[0089] The deformability parameter may be determined by applying a measuring pressure to the fish product, by determining a deformation of the fish product obtained by the measuring pressure, and by determining a ratio between the measuring pressure and the deformation.

[0090] The measuring pressure may be selected to elastically deform the fish product without plastically deforming the fish product. This may prevent permanent deformation and thus a potential quality reduction of the fish product. The elastic range could be provided based on experiments for a certain batch of fish or species of fish. When the deformability meter structure has access to the elastic range, it can use this knowledge to apply only measuring pressures within that range.

[0091] The processing of the fish product may comprise pin boning a fish fillet while the pressing structure is pressed against the fish fillet with the engagement pressure, particularly against the exposed meat surface of the inner side of the fish fillet, to make end portions of pin bones project from a surface of the fish fillet.

[0092] The processing of the fish product may comprise skinning a fish fillet while the pressing structure is pressed against the fish fillet with the engagement pressure, particularly against the exposed meat surface of the inner side of the fish fillet.

[0093] The processing may comprise de-capitating a fish while the pressing structure presses against the fish near its collar bone with the engagement pressure.

[0094] The method may further comprise any steps being implicit in the description of the apparatus according to the first aspect of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Figs. 1-3 illustrate an apparatus for pin boning fish fillets;

[0096] Figs. 4-6 illustrate details of a deformability meter structure;

[0097] Figs. 7-8 illustrate further details of the apparatus in the form of a pin boning apparatus;

[0098] Fig . 9 illustrates a perspective view of an apparatus for skinning fish fillets;

[0099] Figs. 10-11 illustrate a perspective view of an apparatus for de-capitating a fish;

[0100] Fig . 12 illustrates schematically a collar claw;

[0101] Fig . 13 illustrates a fish gripped by the collar claw just behind the collar bone;

[0102] Fig . 14 illustrates a process diagram illustrating a method of pin boning a fish fillet; and

[0103] Fig . 15 illustrates a meter structure for determining the deformability parameter at different locations of a fish product.

[0104] The drawing figures are not necessarily drawn to scale. Instead, they are drawn to provide a better understanding of the components and are not limited in scope but to provide exemplary illustrations. The figures illustrate exemplary configurations of the apparatus and in no way limit the structures or configurations of the apparatus according to the present disclosure.

[0105] DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

[0106] Embodiments of an apparatus overcome limitations of existing systems by providing an apparatus that advantageously allows for better yield without compromising the quality of the processing. In the following, the apparatus for processing fish products is exemplified by three different devices. Figs 1-3 and 7-8 relate to a pin boning apparatus, Fig. 9 illustrates a skinning apparatus, and Figs. 10-13 illustrate a de-capitating apparatus. Correspondingly, the fish product is a fish fillet relative to the pin boning and the skinning apparatuses and considered to be a whole fish with or without entrails and tail etc. when considering the decapitating apparatus. The remaining figures relate to processing in general including pin boning, skinning, and de-capitating . Fig. 1 illustrates an apparatus 1 for pin boning fish fillets. The apparatus comprises a conveyor 2 with a conveyor surface 3 carrying a fish fillet 4 with a lateral outer side of each fish fillet towards the conveyor surface 3 and an opposite lateral inner side 5 of each fish fillet facing away from the conveyor surface. The conveyor is typically a belt conveyor.

[0107] The apparatus comprises a pressing structure 6 arranged to compress a pin bone portion of the exposed meat surface of the lateral inner side of a fish fillet in the stream of fish fillets with an engagement pressure while the fish fillet is conveyed.

[0108] The engagement pressure against the surface forces the end portions of the pin bones out of the lateral inner side of the fish fillet and thereby enables that the pin boning structure 7 can catch the pin bones and pull them out of the fish fillet. The pressing structure is illustrated only schematically by a pressure element applying the engagement pressure against the surface of the fish fillet. The pressing structure also comprises an actuator 8 which is only illustrated schematically.

[0109] The actuator 8 is configured for adjusting the pressure. Such an actuator could be implemented with a counterweight 9 being movable by a servo drive or step motor to thereby apply a variable weight onto the pressure element.

[0110] The apparatus comprises an electronic control structure 10 configured to read a deformability parameter representing an ability of the fish product to deform. Based on the deformability parameter, the electronic control structure controls the pressing structure 6 to engage the pin bone portion with an engagement pressure such that this pressure depends on the deformability parameter.

[0111] The control structure 10 may e.g., use standard hardware circuits, using software programs and data in conjunction with a suitably programmed digital microprocessor or a general- purpose computer e.g. a PLC programmed with suitable computer code for enabling translation of the deformability parameter into corresponding control codes for controlling the pressing structure. The control structure may include an application specific integrated circuitry, e.g. using standard servo systems or step motors controllers for controlling servo drives or step motors of the pressing structure to thereby apply the engagement pressure which is adequate for the specifically read deformability parameter of a specific fish product.

[0112] Electronic control structure 10 may be constituted by a CPU with memory and computer executable code for enabling various functions including reading the deformability parameter and providing control instructions for the pressing structure. Software program instructions and data may be stored on a non-transitory, computer-readable storage medium, and when the instructions are executed by the CPU these functions are carried out. In one example, the electronic control structure comprises an empirical model translating the deformability parameter into control codes for the pressing structure, this could e.g., be a model represented by a table of different values of the deformability parameter and corresponding control codes.

[0113] The electronic control structure comprises a data interface 11 configured to communicate the deformability parameter of the fish product between an external data interface and in internal data interface 12 configured for controlling the pressing structure 6 via the control interface 13.

[0114] Fig. 2 illustrates the apparatus seen in a side view and Fig. 3 illustrates an enlarged view of the pressing structure 6, the processing structure 7 which, in this case, is a pin boning structure, and the counterweight 9.

[0115] The counterweight 9 is mounted to a comb structure 20 by a connector part 21 which is axially extendable in the direction indicated by the arrow 22. The connector part could be constituted by a linear actuator of a kind known in the art, e.g. based on a rotatable spindle etc. and controllable as a servo-controlled drive.

[0116] Processing structure 7 comprises a pin boning roll 23 of a kind known in the art. Such a roll comprises longitudinal grooves 24. Due to the engagement pressure applied to the inner side of the fish fillet by pressing structure 6, the end portions of the pin bones will stick slightly out of the fish fillet. During processing, the pin boning roll 23 rolls with a rotational speed matching the conveying speed of the fish fillet such that the end portions of the pin bones can get caught in grooves 24, and as the fish fillet passes the pin boning roll, the pin bones are pulled out of the fillet. The pin bones, now stuck in the grooves, subsequently pass the comb structure 20 which pulls the pin bones out of the grooves, and they are finally removed from the apparatus by blowing water or air across the comb structure.

[0117] Fig. 4 illustrates schematically further details of an apparatus for processing fish products, e.g. a pin boning, a skinning, or a de-capitating apparatus. The apparatus defines a conveying direction indicated by arrow 40 and includes a deformability meter structure 41 arranged upstream the pressing structure 6 and processing structure 7, e.g. a pin boning structure, a skinning structure, or a de-capitating structure.

[0118] The deformability meter structure is configured to determine the deformability parameter.

[0119] The deformability meter structure comprises two deformability sensors 50, 60 illustrated in further detail in Figs. 5 and 6. The deformability meter structure is described further in the following and can determine the deformability parameter for each fish product being processed.

[0120] The deformability meter structure may function by applying pressure to the fish product and by determining a deformation of the fish product obtained by the pressure. The ratio between the pressure and the deformation may indicate the deformability of the fish product.

[0121] The deformability sensors 50, 60 may be arranged to apply different pressure to the fish product and to record a corresponding position of the surface of the fish product where the pressure is applied.

[0122] The first sensor may e.g., register a thickness of the fish product with a first pressure, and the second sensor may register a thickness of the fish product with a second pressure. The deformability parameter of the fish product, dF, could be provided by inserting dimp and dP into the deformability parameter equation dV=dimp / dP.

[0123] When using several deformability sensors, each sensor may apply a pressure different from the pressure of the other sensors. In one example, a first measuring station comprises a device for measuring the thickness of the fish product. This device may not apply pressure, or at least only apply a very small pressure which essentially provides no deformation of the fish product. This measuring station could be considered as one of the deformability sensors since it provides a thickness of the fish product when no force is applied. Such a station is illustrated in Fig. 5.

[0124] A subsequent measuring station may comprise an element being pressed sideways against the fish product, and the thickness may simultaneously be determined. Such a station is illustrated in Fig. 6.

[0125] Fig. 5 illustrates a deformability sensor 50 forming part of the deformability meter structure. In this case, it is further configured to determine the thickness of the fish product. The measuring structure comprises a conveyor 51 on which the fish product is conveyed in a sideways orientation in which one lateral side faces the conveyor and the other lateral side faces the hinged plate element 52 under which the fish product is conveyed. The fish product lifts the hinged plate element while the plate element pivots about a pivot point 53. The angular displacement of the hinged plate determines the thickness of the fish product. At the same time, the hinged element exerts almost no pressure on the fish product or only a pressure which is inessential to the thickness of the fish product by registering the ratio between this applied pressure, i.e., almost no pressure, and the corresponding deformation of the fish product, the measuring structure provides a measure of a dimension of the fish product when essentially no pressure is applied to the fish product. The measuring structure illustrated in Fig. 5 may also, with the same structure, be configured to determine the length of the fish product. In this configuration, the length is determined by the speed of the conveyor and by the angular displacement of the plate element. When the fish enters under the plate element, the plate swings upwardly, until the fish has passed through the measuring structure. Accordingly, the length of the fish product can be determined based on the speed of the conveyor and the duration from the point in time where the displacement of the plate element starts until the plate element is back in its lowermost position. At the same time, the hinged element exerts a certain pressure on the fish product, i.e., essentially only a low pressure caused by the weight of the plate element, and by registering the ratio between this applied pressure and the corresponding deformation of the fish product, the measuring structure may be used both for length measurement and as a first deformability sensor forming part of the deformability meter structure and providing a first data set of pressure and a corresponding dimension of the fish product.

[0126] If the thickness, i.e. the highest dimension of the fish product above the conveyor surface is already known, then the ratio between the pressure or angular position of the plate element and the dimension of the fish product may be used directly as a measure of the deformability parameter. However, if the thickness of the fish product is unknown, the first deformability parameter sensor may be useful in combination with a second deformability sensor since the first sensor may provide the thickness of the fish product and the second may subsequently provide the deformation.

[0127] Conveyor 51 may be constituted by conveyor 2, or it may form part of a continuous conveying system which also includes conveyor 2 and thereby allowing the fish product to be conveyed directly from the measuring of the deformability parameter to the pin boning, skinning, and / or de-capitation process.

[0128] Fig. 6 illustrates an additional, second deformability sensor 60 forming part of the deformability meter. Again, in this embodiment, the fish product is conveyed in a sideways orientation with a lateral side facing the conveyor 61 and the other lateral side faces the hinged plate element 62. The fish product lifts the hinged plate element while the plate element pivots about a pivot point 63. In this case, plate element 62 has a higher weight due to the weight element 64. By registering, again, the ratio between this applied pressure and the corresponding deformation of the fish product, the second deformability sensor provides a second data set of larger pressure and a corresponding dimension of the fish product. By comparing the difference between the deformation, i.e. the difference between the angular orientation of the two plate elements 52, 62 with the different weights, the deformability meter can provide a parameter for the deformability. The conveyor 61 may be constituted by conveyor 2, or it may form part of a continuous conveying system which also includes conveyor 2 and thereby allowing the fish product to be conveyed directly from the measuring of the deformability parameter to the pin boning, skinning, and / or de-capitating process.

[0129] By means of an example, the thickness is known already, and the apparatus comprises only the deformability sensor 50. This sensor may be configured for applying a downwards force to a fish product in the order of 2 Newton. With a particular fish product, the thickness (corresponding to the height of the fish fillet above a conveyor surface) is known to be e.g., 2 cm along a part of the length, and the angular position of the deformability sensor 50 is convertible into 1,7 cm when the fish product passes under the deformability sensor 50. This is translated into 0,3 cm divided with 2 Newton, equivalent to 0,15 cm / N which could be an example of a deformability parameter.

[0130] By means of another example, the thickness is unknown, and the apparatus comprises an additional, second deformability sensor 60. This sensor may be configured for applying a downwards force to a fish product in the order of 4 Newton. With the above example of a particular fish product, the thickness was 1,7 cm along a part of the length measured with a 2 Newton downward force and the angular position of the deformability sensor 60 now measures a 1,4 cm thickness along the same part of the length when the fish product passes under the second deformability sensor 60. This is translated into (1,7-1, 4) cm=0,3 cm divided with (4-2) Newton, i.e., again a deformability parameter of 0,15 cm / N.

[0131] Figs. 7 and 8 illustrate two different embodiments of the apparatus when forming a pin boning apparatus and seen in an upstream direction against the conveying direction illustrated with the arrow 70. In this view, it is more clearly shown that the pressing structure is prior to the pin boning structure in the flow of fish fillets.

[0132] In Fig. 7, the pin boning roll forms at least a part of the pressing structure and the roll pressure indicated by the arrow 71 depends on the engagement pressure or is identical to the engagement pressure.

[0133] In Fig. 8, the pressing structure comprises a pre-pressing structure in the form of a comb with teeth 81. Alternatively, it could be a plate shaped element or a roll. The pre-pressing structure provides a pre-pressure indicated by the arrow 82 which depends on the engagement pressure or is identical to the engagement pressure.

[0134] Fig. 9 illustrates an apparatus wherein the processing structure 7 is configured for skinning fish fillets. The apparatus comprises a conveyor 2 with a conveyor surface 3 configured for carrying fish fillets. The fish fillets are carried with a lateral outer side of each fish fillet towards the conveyor surface 3 and an opposite lateral inner side of each fish fillet facing away from the conveyor surface. The apparatus comprises a pressing structure 6 arranged to compress a portion of the lateral inner side of a fish fillet in the stream of fish fillets with an engagement pressure while the fish fillet is conveyed.

[0135] The engagement pressure against the surface forces the lateral outer side of the fillet against the surface of the counter pressure roll 91 such that the fish fillet is squeezed between the pressing structure 6 and the counter pressure roll 91 when it reaches the skinning knife 92.

[0136] The pressing structure is illustrated only schematically by a pressure element applying the engagement pressure against the surface of the fish fillet. The pressing structure also comprises an actuator for adjusting the pressure. Such an actuator could be implemented in various ways inter alia with a counterweight being movable by a servo drive or step motor to thereby apply a variable weight onto the pressure element.

[0137] Figs. 10 and 11 illustrate an apparatus wherein the processing structure 7 is for de-capitating fish. The apparatus comprises a gripper holding the fish in a fixed position. The gripper comprises a plurality of claws 103 holding the fish, and a collar claw 6 constitutes the pressing structure arranged to compress the fish near its collar bone.

[0138] By applying the engagement pressure, the collar claw is adjusted based on the deformability of the fish, and the head position becomes more uniform, and the head is cut correctly even when the deformability changes between different fish.

[0139] The collar claw is operated by a separate servo system, and the additional claws 103 can therefore operate with a pressure which is different from the engagement pressure at which the collar claw is operated.

[0140] Fig. 11 illustrates the gripper and the knives 101, 102 which are arranged to cut close to the collar claw 106. Particularly, the knives are two circular blades forming a V-shape and moving along a surface of the collar claw.

[0141] Fig. 12 illustrates the collar claw seen from above and illustrates how the knives 101, 102 follow an outer surface of the collar claw. The collar clow compress with the engagement pressure right behind the collar bone of the fish and since the knives cut close to the surface, the head is cut off close to the collar bone and with the collar bone remaining on the head part. Since the collar claw applies the engagement pressure which depends on the deformability of the fish, the position of the collar bone relative to the collar claw becomes more uniform amongst the different fish irrespective of the difference in deformability of the fish. Accordingly, the knives can cut closer to the collar claw and the amount of wasted meat on the head part can be reduced.

[0142] Fig. 13 illustrates how collar claw 6 compresses a fish 130 right behind its collar bone and thereby positions the head in a correct position for the knives to cut close to the collar bone while still leaving the collar bone on the head part which is considered less valuable than the remaining body part of the fish.

[0143] Fig. 14 illustrates a process diagram illustrating a method of pin boning a fish fillet. In this diagram, the first process, A, is a step of receiving a plurality of fish fillets on a conveyer configured to convey the fish fillet in a row of fish products. Step B is a sensing step in which a deformability meter structure determines the deformability parameter by gently compressing the fish fillet while tracking the pressure against the surface of the fish fillet. Step C is a step of determining a control signal for a pressing structure. This step includes a calculation of a force which should be applied onto the surface of the fish fillet by the pressing structure. Step D is a step of compressing a pin bone portion of the fish fillet using a pressing structure until the end portions of the pin bones appear on the surface of the fish fillet. The compressing is carried out by the force calculated in step C. Finally, step E is a step of removing pin bones from the fish fillet.

[0144] Fig. 14 may alternatively illustrate a process of skinning a fish fillet. In this case, the first process, A, is a step of receiving a plurality of fish fillets on a conveyer configured to convey the fish fillets in a row of fish fillets. Step B is a sensing step in which a deformability meter structure determines the deformability parameter by gently compressing the fish fillet while tracking the pressure against the surface of the fish fillet. Step C is a step of determining a control signal for a pressing structure. This step includes a calculation of a force which should be applied to the fish fillet by the pressing structure. Step D is a step of compressing the fish fillet using a pressing structure. Finally, step E is a step of skinning the fish fillet as it passes a knife structure while it is compressed by the pressing structure.

[0145] Fig. 14 may alternatively illustrate a process of de-capitating a fish. In this case, the first process, A, is a step of receiving a plurality of fish on a conveyer configured to convey the fish in a row of fish. Step B is a sensing step in which a deformability meter structure determines the deformability parameter by gently compressing the fish while tracking the pressure against the surface of the fish. Step C is a step of determining a control signal for a pressing structure. This step includes a calculation of a force which should be applied by a collar claw of a fish gripper. The collar claw constitutes the pressing structure and places the head correctly relative to the knives. Step D is a step of compressing the fish using a pressing structure. Finally, step E is a step of removing the head by moving the knives relative to the collar claw. Fig. 15 illustrates a deformability meter structure comprising plurality of sensors for applying the measuring pressure to the fish product. In this embodiment, the sensors are located at the same position along the conveyor system, and the sensors are configured to obtain deformability parameters for different locations of the same fish. The sensors comprise finger shaped elements 150 pressing at different locations on the fish. The resulting plurality of deformability parameters for a fish may be useful since one fish may be pressed differently at different locations during the processing. As an example, a fish fillet may have a different deformability along one edge of the fish fillet compared with the deformability at the center of the fish fillet. The finger shaped elements may press with an identical pressure or with individual pressures.

[0146] The specifically disclosed deformability meter structure is configured for fish which have not yet been filleted, i.e. fish having two sides fixed at the backbone of the fish. During the determination of the deformability parameters, the fish ride with the backbone along the center plate 151.

Claims

CLAIMS1. An apparatus (1) for processing a fish product, the apparatus comprising :- a pressing structure (6) arranged to engage the fish product with an engagement pressure to thereby influence the shape of the fish product;- a processing structure (7) for processing the fish product while the pressing structure engages the fish product with the engagement pressure; and- an electronic control structure (10) configured to read a deformability parameter representing ability of the fish product to deform, and to control the pressing structure to engage the fish product with an engagement pressure which depends on the deformability parameter.

2. The apparatus according to claim 1, wherein the deformability parameter exclusively represents an ability of the fish product to deform elastically.

3. The apparatus according to claim 1 or 2, comprising a conveyor (2) for conveying in a downstream direction, a stream of the fish products in the form of fish fillets with a lateral outer side and a lateral inner side; wherein the pressing structure (6) is arranged to compress a pin bone portion of the lateral inner side with the engagement pressure while the fish fillet is conveyed to thereby force an end portion of the pin bones out of the lateral inner side of the fish fillet; and wherein the processing structure (7) forms a pin boning structure configured for pin boning the lateral inner side while the fish fillet is conveyed and while the pin bone portion is compressed by the pressing structure.

4. The apparatus according to claim 3, wherein the pressing structure is configured to compress the pin bone portion with an engagement pressure which varies in a length direction of the fish fillet.

5. The apparatus according to claim 3 or 4, wherein the pin boning structure is configured for pin boning the lateral inner side while the fish fillet is conveyed on the conveyor with the lateral inner side facing upwards and away from the conveyor.

6. The apparatus according to claim 5, wherein the pin boning structure comprises a pin boning roll (23) arranged to roll with a roll pressure against the pin bone portion.

7. The apparatus according to claim 6, wherein the pin boning roll forms at least a part of the pressing structure and the roll pressure depends on the engagement pressure or is identical to the engagement pressure.

8. The apparatus according to any of claims 3-7, comprising a bone raising structure arranged upstream the pin boning roll.

9. The apparatus according to any of claim 6-8, wherein the pin boning roll and the pressing structure are joined, the apparatus comprising an adjustment structure allowing adjustment of a position of the pin boning roll relative to the pressing structure.

10. The apparatus according to claim 9, wherein the adjustment structure is configured to adjust the position depending on the engagement pressure.

11. The apparatus according to claim 1, comprising :- a conveyor (2) for conveying a stream of the fish products in the form of fish fillets with a lateral outer side of each fish fillet (4) towards a surface (3) of the conveyor and an opposite lateral inner side (5) of each fish fillet facing away from the conveyor surface; wherein the pressing structure (6) is arranged to press the lateral outer side of a fish fillet towards the surface (3) of the conveyor while the fish fillet is conveyed; and wherein the processing structure (7) forms a skinning structure configured for removing skin from the lateral outer side while the fish fillet is conveyed and while the portion of the lateral inner side of the fish fillet is compressed by the engagement pressure applied by the pressing structure.

12. The apparatus according to claim 11, wherein the electronic control structure is configured to control the pressing structure to engage the fish fillet with an engagement pressure which varies for different parts of the fish fillet.

13. The apparatus according to claim 1, comprising a gripper arranged to grip the fish product in the form of a fish;wherein the pressing structure (6) forms part of the gripper which is arranged to compress a gripped portion of the fish with the engagement pressure; and wherein the processing structure (7) forms a de-capitating structure configured for removing the head of the fish while the fish is compressed by the gripper.

14. the apparatus according to claim 13, wherein the gripper comprises a row of individual claws, the row comprising a collar claw terminating one end of the row and being configured to grip near or at the collar bone of the fish, and wherein the compression of the gripped portion of the fish with the engagement pressure is caused by the collar claw.

15. The apparatus according to any of the preceding claims, comprising a data interface configured to communicate the deformability parameter of the fish product with an external data interface.

16. The apparatus according to any of the preceding claims, comprising a deformability meter structure arranged upstream the pressing structure and configured to determine the deformability parameter of the fish product before the fish product reaches the pressing structure.

17. The apparatus according to claim 16, wherein the deformability meter structure is configured to apply a measuring pressure to the fish and to determine a deformation of the fish product obtained by the pressure.

18. The apparatus according to claim 17, wherein the deformability meter structure is configured to determine a ratio between the measuring pressure and the deformation.

19. The apparatus according to any of claims 16-18, wherein the deformability meter structure comprises at least two deformability sensors for applying the measuring pressure to the fish product.

20. The apparatus according to claim 19, wherein the at least two deformability sensors are displaced relative to each other along the conveyor.

21. The apparatus according to claims 19-20, wherein the at least two deformability sensors are configured to apply different measuring pressures to the fish product.

22. The apparatus according to any of claims 19-21, wherein the deformability meter structure is configured to calculate a difference between measurements of the at least two deformability sensors, and wherein the deformability parameter is based on the difference.

23. The apparatus according to any of claims 17-22, wherein the deformability meter structure is configured to apply the measuring pressure to the fish product such that the measuring pressure elastically deforms the fish product without plastically deforming the fish product.

24. The apparatus according to any of claims 16 or 23, wherein the deformability meter structure comprises at least one sensor configured to determine the deformability parameter at a sensing spot on the surface of the fish product.

25. The apparatus according to any of the preceding claims, wherein the processing structure is not suitable for filleting a fish.

26. The apparatus according to any of the preceding claims, wherein the pressing structure is arranged to engage an exposed meat surface of the fish product with the engagement pressure to thereby influence the shape of the meat of the fish product.

27. The apparatus according to any of claims 17-26, wherein the deformability meter structure is configured to apply the measuring pressure to an exposed meat surface of the fish product and to determine the deformation of the exposed meat surface of the fish product obtained by the pressure.

28. A method for processing a fish product, the method comprising :- pressing a pressing structure against the fish product with an engagement pressure to the fish product; and- processing the fish product while the shape is influenced by the engagement pressure; wherein the engagement pressure is determined by reading a deformability parameter representing an ability of the fish to deform, and determining the engagement pressure based on the deformability parameter, to thereby process the fish product.

29. The method according to claim 28, wherein the deformability parameter is determined by applying a measuring pressure to the fish product, by determining a deformation of the fishproduct obtained by the measuring pressure, and by determining a ratio between the measuring pressure and the deformation.

30. The method according to claim 29, wherein the measuring pressure is selected to elastically deform the fish product without plastically deforming the fish product.

31. The method according to any of claims 28-30, wherein the processing of the fish product comprises pin boning a fish fillet while the pressing structure is pressed against the fish fillet with the engagement pressure to make end portions of pin bones project from a surface of the fish fillet.

32. The method according to any of claims 28-30, wherein the processing of the fish product comprises skinning a fish fillet while the pressing structure is pressed against the fish fillet with the engagement pressure.

33. The method according to any of claims 28-30, wherein the processing of the fish product comprises de-capitating a fish while the pressing structure presses against the fish near or at its collar bone with the engagement pressure.

34. The method according to any of the claims 28-33, wherein the fish product is a fish or a fillet of a fish selected from the Salmonidae family.

35. The method according to any of the claims 28-34, wherein the processing of the fish product is not filleting of a fish.

36. The method according to any of the claims 28-35, wherein pressing is against exposed meat of the fish product.

37. The method according to any of the claims 29-36, wherein measuring pressure is applied to exposed meat of the fish product.

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