fish filleting machine

Abstract

A machine (1) for filleting fish, comprising a filleting station with two circular rotating cutting blades arranged to perform a planar cut in the fish, the cutting blades being movable towards or away from each other by a linear actuator to increase the yield.

Description

[Technical field]

[0001] The present invention relates to a machine for cutting fillets from the vertebrae of fish. [Background technology]

[0002] Filleting a fish generally involves removing the head and viscera of the fish. The fish is then split lengthwise and vertically into three pieces: two side pieces, referred to herein as "fillets," and one middle piece, referred to herein as the "skeleton." The skeleton includes the vertebrae.

[0003] In the following text, the anatomical structures of fish will be referred to as follows:

[0004] The dorsal portion of a fish is that portion that extends upward from the vertebrae to the top of the fish's back. This portion terminates upwardly by what is referred to herein as the "dorsal edge" of the fish, i.e., the dorsal edge is the upper edge of the fish.

[0005] The ventral part of a fish is the portion extending downward from the vertebrae and includes the abdomen or abdomen together with the tail, which is located between the abdomen and the tail. This portion terminates downwardly by what is referred to herein as the "ventral edge" of the fish, i.e., the ventral edge is the lower edge of the fish.

[0006] The vertical midplane is an imaginary plane introduced to aid in the definitions herein: it is a longitudinal vertical plane that passes through the middle of the vertebrae and intersects centrally between the two fillets.

[0007] The skeleton is simply used for industrial purposes, such as for example the production of fishmeal, whereas the fillets, with or without skin, represent the valuable part of the fish and can be further processed, for example by smoking.

[0008] Generally, the process of filleting at least some fish species is widely automated. In existing machines, one or more knife devices fillet the fish by either cutting through one end of the fish, or by cutting partially through the dorsal and ventral edges of the fish. Most often, the filleting machine is provided with one or more pairs of adjacent two circular rotating knife blades. Apparently, the rotating knife blades make planar cuts in the fish.

[0009] To prevent the loss of valuable fish meat, some machines are provided with a pair of circular knife blades arranged to form an angle between them. In this way, the blades define an area with a relatively open gap and an opposing area with a relatively narrow gap. In this way, the blades can cut a triangular section from the fish relatively close to the vertebrae. However, because each blade makes a primarily flat cut, a relatively large amount of meat, especially at the ventral edge of the fish, is cut from the fillet and removed along with the worthless skeleton.

[0010] In some machines, a band knife is used to free the fillet from the vertebrae and backbone of the fish. Summary of the Invention

[0011] It is an object to improve the yield and quality of the fillets. For this and other objects a machine and method for filleting fish is provided according to the independent claims. Other objects are to provide a system which reduces the risk of mechanical failure, reducing stoppages in the filleting process due to e.g. fish parts getting caught in the machine, reducing inspection times and thus providing a system which can function for a longer time.

[0012] The machine may have several filleting stations and may further have other processing stations, for example a harvesting station arranged to harvest fins and / or fat and cartilage from the fish. Other processes, for example image capture and quality control, may also be part of the machine.

[0013] The filleting station may be based on either a planar cut, generally a rotating disk, and a band knife capable of making curved cuts. The cutting station is generally based on a planar cut, generally a rotating disk.

[0014] The machine is a first cutting blade disposed on one side of a vertical central plane and configured to cut fish while the first cutting blade rotates about a first axis of rotation; a second cutting blade disposed on an opposite side of the vertical central plane and configured to cut the fish while the second cutting blade rotates about the second axis of rotation; a gap control structure configured to vary a gap between the first cutting blade and the second cutting blade based on the detected width of the fish while the fish is being cut; At least one flat cutting fillet station having a

[0015] To improve the ability to make precise cuts, particularly for filleting purposes, the planar cut filleting station may be configured to maintain a fixed angle between the first and second cutting blades during gap changes, such that the gap can be adjusted while the angle between the blades is maintained.

[0016] The gap control mechanism may be configured to vary the gap by linear movement of both cutting blades inwardly toward each other or outwardly away from each other, which allows for fast control and transfer of relatively large forces with good precision, and may further simplify construction and increase reliability, as compared to, for example, rotational movement of the cutting blades about a hinge point.

[0017] The gap control structure may be configured to vary the gap by linear motion in a direction that is not perpendicular to the downstream direction, for example. In one example, the gap control structure may be configured to vary the gap by linear motion in a direction toward the corresponding axis of rotation of each of the first and second cutting blades, i.e., perpendicular to the circular blades. This direction may form an angle that is not perpendicular to the downstream direction, for example, an angle on the order of 80-85° to the downstream direction.

[0018] The first axis of rotation may not be parallel to the second axis of rotation. If the linear motion is in the direction of the axis of rotation, it means that the motion of one of the circular blades is in one direction and the motion of the other circular blade is in the other direction.

[0019] One of the at least one flat cut filleting stations may form a ventral filleting station arranged to cut the fish along a ventral edge of the fish, and the other of the at least one filleting station may form a dorsal filleting station arranged to cut the fish along a dorsal edge of the fish.

[0020] The gap control structure may be configured to vary the gap by symmetrical movement of both cutting blades relative to the vertical center plane, but may also be configured to control the first blade completely independently of the second blade, or vice versa, to increase yield.

[0021] The machine may be equipped with a lifting structure for lifting the fish. This is relevant during the operation of the ventral filleting station. When the fish is cut by the ventral filleting station, it is generally intended to cut only the last part in the length direction, close to the tail, the ventral part having the ventral bone, and it is often desirable to free the fillet from the ventral bone by using a more flexible band knife that can make a curved cut. If the front end of the fish is not lifted, the first and second cutting blades may accidentally cut through the ventral bone, making it difficult or impossible to make fillets with the knives of the later bands.

[0022] The lifting structure is for example defined by a plate which rotates about a drive axis extending perpendicular to the plate.

[0023] This causes the points of the plate, particularly the corner points, to rotate circumferentially in a vertical central plane. These points are referred to herein as "lifting points". During rotation, these points are configured to sequentially engage and lift vertebral points along the lower edge of the vertebrae of the fish in the series. Rotation of the plate allows it to move downstream while in contact with the vertebrae, and rotates to disengage the vertebral points as it moves to a level below the fish. Further rotation then allows it to engage and lift vertebral points along the lower edge of the vertebrae of subsequent fish in the series.

[0024] In one example, the lifting point glides relative to the vertebrae during movement, in another example, the speed of the lifting point is adjusted to match the speed of transport of the fish, in which case the lifting point may be stationary relative to the vertebrae point.

[0025] To protect the fish from damage whilst at the same time ensuring a firm grip during transport of the fish and therefore optimum control of the position of the first and second knife blades during cutting, the transport system may have an adjustable entrance clearance.

[0026] The transport system may in particular form at least one endless belt on one side of a vertical central plane and at least one endless belt on an opposite side of the vertical central plane.

[0027] Each of the belts extends between an upstream pulley and a downstream pulley, and an inlet gap is defined between the upstream pulleys.

[0028] The machine may comprise an inlet clearance controller arranged to read the detected width and control the position of at least one of the upstream pulleys relative to the position of the other upstream pulley to vary the inlet clearance based on the width, thereby allowing good protection and a firm grip and therefore accurate positioning of the fish as it moves through the machine.

[0029] When the fillets and skeleton are delivered to the outfeed, the fillets are fragile, mainly because they are no longer supported by the skeleton. The machine can provide a controllable exit gap to protect the fillets and reduce damage.

[0030] The conveying system may thus define an exit gap defined between the downstream pulleys to deliver the string of fish between the endless belts, and an exit gap controller configured to read the detected width and control the position of at least one of the downstream pulleys relative to the position of the other downstream pulley to vary the exit gap based on the width of the fish detected upstream of the exit gap, such as upstream of the entrance gap.

[0031] The conveying system may define a first section having a first endless belt on one side of a vertical central plane and a second endless belt on an opposite side of the vertical central plane, and the machine includes a second section downstream of the first section having a third endless belt on one side of the vertical central plane and a fourth endless belt on the opposite side of the vertical central plane, the first section extending at a first height and the second section extending at a second height different from the first height.

[0032] As mentioned above, the machine may have a cutting station in addition to the filleting station. One cutting station may for example be provided for cutting the back part, referred to herein as the back cutting station, and the other for cutting the ventral part, referred to herein as the ventral cutting station. The back cutting station may be arranged in one of the first and second conveying sections, and the ventral fillet station may be arranged in the other section of the conveying system. In particular, the section of the conveying system in which the back cutting station is arranged may be at a lower height than the section in which the ventral fillet station is arranged, thereby obtaining more space for making the cutting cuts.

[0033] In one example, the dorsal cutting station is located upstream relative to the ventral cutting station and the first section of the conveying system is at a lower elevation than the second section of the conveying system.

[0034] As mentioned above, it may be desired to free the fillets from the vertebrae and ventral bones by a knife capable of making a curved cut. To that end, the machine may include a band knife arrangement arranged downstream relative to at least one planar cut fillet station. The band knife may have two flexible, rotating, closed-loop knife bands arranged to provide a curved cut on either side of the vertebrae of the fish while the fish is advanced between the two belts.

[0035] A pair of pushing nippers are positioned to provide pushing pressure on the right and left sides of the fish against the two belts, for example by use of pneumatic or spring actuators which push plates against the outer surface of the fish.

[0036] The abdominal plate structure having two abdominal plates can be placed between the left and right abdominal sides. The abdominal sides are pushed outward by the abdominal plates towards the pushing nippers. During this process, the gap between the abdominal plates changes according to the size of the fish.

[0037] The machine may be equipped with a belly plate motor structure controlled based on the width of the fish to vary the belly plate gap between the belly plates according to the width of the fish. In this way, the belly plates can be more precisely controlled, potentially leading to better yields with the bandknife.

[0038] At least one, but preferably all, of the planar cutting fillet stations may have a height control structure configured to vary the height of the first and second cutting blades while the fish is being cut. The height adjustment may in particular be made at a fixed angle between the first and second cutting blades, in particular by means of a linear actuator.

[0039] The height detection mechanism may be located at an upstream position relative to the filleting station and configured to detect the height of the fish, i.e. the dimension from the ventral edge to the dorsal edge.

[0040] The height control structure may be configured to vary the height of the first and second cutting blades based on the detected height of the fish.

[0041] The machine may further comprise a length detection mechanism disposed at an upstream position relative to the filleting station and configured to detect the length of the fish.

[0042] The gap control structure and / or height control structure may then use the length in varying the gap or height of the first and second cutting blades.

[0043] The first cutting blade may be formed in a first cutting unit having at least a part of the gap control structure. More specifically, the first cutting unit may define a chassis to which a rotation motor and a displacement motor are fixed. These two motors respectively cause the displacement and rotation of the corresponding cutting blade, which may be detached from the machine as one single component for easy inspection and repair.

[0044] In order to provide a slim, robust and space-optimized design, the first cutting unit may have a drive shaft extending in the direction of the first rotation axis, the drive shaft being connected to the cutting blade and rotated by a rotation motor. The displacement motor may be arranged to displace the drive shaft and the cutting blade as one component, for example by displacing an outer tube in which the drive shaft is supported.

[0045] The drive shaft may have an elongated tooth structure configured to engage with a rotational motor during displacement, thereby allowing continuous rotation and cutting while displacing the blade laterally to adjust the gap.

[0046] The rotational engagement may include engagement between a drive wheel of the rotary motor and an elongated cogwheel extending in the direction of the first rotational axis on an outer surface of the drive shaft.

[0047] The second cutting blade may be formed in a second cutting unit which is identical to the first cutting unit or may constitute the first cutting unit mirrored in the central plane. In total, the machine may have, for example, four such units, two constituting the dorsal filleting station and two constituting the ventral filleting station. Each unit may have a connector, for example a single plug, for power and signal communication with the machine, in particular for the exchange of control signals with the computer control unit.

[0048] At the time of installation or service, a technician can simply mount the units and the computer control unit can begin a synchronization procedure, for example, where the displacement motors are driven to their extreme positions so that their positions are known to the control unit. The gap can then be controlled by operation of one or both displacement motors in one of the dorsal and / or ventral fillet stations.

[0049] In a second aspect, the disclosure provides a method of filleting fish by use of said machine. The method may comprise moving the first and second cutting blades towards or away from each other while cutting the fish without changing the angle between the blades. This allows the gap to be dynamically adjusted throughout the cut of the dorsal portion. Dynamic adjustment of the cutting blades may also be provided when cutting the ventral portion of the fish. By dynamic it is meant "while the fish is being cut or measured".

[0050] In a third aspect, the present disclosure provides a machine for filleting fish, the machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with a dorsal side of the fish facing upward and left and right sides of the fish on opposite sides of a vertical center plane; at least one filleting station arranged to cut the fish as it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; Equipped with The machine includes a lifting structure defining rotatable lifting points along a circumference in a vertical central plane, the lifting points being configured during rotation to sequentially engage and lift vertebral points along the lower edge of the vertebrae of a fish in the series, move downstream while in contact with the vertebrae, e.g. while in contact with the vertebral point, disengage from the vertebrae, and engage and lift the vertebral point along the lower edge of the vertebrae of the next fish in the series.

[0051] In a fourth aspect, the present disclosure provides a machine for filleting fish, the machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with a dorsal side of the fish facing upward and left and right sides of the fish on opposite sides of a vertical center plane; at least one filleting station arranged to cut the fish as it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with The conveying system forms an endless belt on one side of a vertical central plane and an endless belt on an opposite side of the vertical central plane, each of the endless belts extending between an upstream pulley and a downstream pulley, an inlet gap being defined between the upstream pulleys for receiving a string of fish between the endless belts, and the machine further comprises an inlet gap controller configured to read the detected width and control a position of at least one of the upstream pulleys relative to a position of the other upstream pulley to vary the inlet gap based on the width of the fish.

[0052] In a fifth aspect, the present disclosure provides a machine for filleting fish, the machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with a dorsal side of the fish facing upward and left and right sides of the fish on opposite sides of a vertical center plane; at least one filleting station arranged to cut the fish as it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with The conveying system has an endless belt on one side of a vertical central plane and an endless belt on an opposite side of the vertical central plane, each of the endless belts extending between an upstream pulley and a downstream pulley, an outlet gap being defined between the downstream pulleys to deliver the string of fish between the endless belts, and the machine further comprises an outlet gap controller configured to read the detected width and control a position of at least one of the downstream pulleys relative to a position of the other downstream pulley to vary the outlet gap based on the width of the fish.

[0053] In a sixth aspect, the present disclosure provides a machine for filleting fish, the machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with a dorsal side of the fish facing upward and left and right sides of the fish on opposite sides of a vertical center plane; at least one filleting station arranged to cut the fish as it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; Equipped with The conveying system forms an upstream conveying section and a downstream conveying section, each of which forms an endless belt on one side of a vertical central plane and an endless belt on an opposite side of the vertical central plane, with the endless belt in one of the upstream and downstream sections extending at a higher height than the other of the upstream and downstream sections.

[0054] In a seventh aspect, the present disclosure provides a machine for filleting fish, the machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with a dorsal side of the fish facing upward and left and right sides of the fish on opposite sides of a vertical center plane; at least one filleting station arranged to cut the fish as it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; Equipped with The machine is a band knife structure disposed downstream relative to the at least one flat cut fillet station and having two flexible rotating closed loop knife bands arranged to provide curved cuts on either side of the fish vertebrae while the fish is advanced between the two belts; a pair of pushing nippers arranged to provide pushing pressure on the right and left sides of the fish against the two belts; an abdominal plate structure having right and left abdominal plates arranged to define an abdominal plate gap between the abdominal plates and arranged to press the right and left sides of the abdomen of the fish away from each other against a compressive pressure; an abdominal plate motor structure controlled based on the width of the fish to change the abdominal plate gap between the abdominal plates according to the width of the fish; It further comprises:

[0055] Any aspect disclosed in relation to the machine of the first aspect may also apply to the machines of the third to seventh aspects. [Brief description of the drawings]

[0056] In the following, embodiments of the present disclosure are explained in more detail with reference to the drawings. [Figure 1] 1 shows a filleting machine. [Diagram 2] Showing a fish with a defined size of fish. [Diagram 3] Showing a fish with a defined size of fish. [Figure 4] Showing a fish with a defined size of fish. [Diagram 5] 1 shows a device for detecting fish width. [Figure 6] 1 shows the transport system of the machine. [Figure 7] 1 shows the transport system of the machine. [Figure 8] 1 shows the transport system of the machine. [Figure 9] 1 shows the transport system of the machine. [Figure 10] Shown is the dorsal filleting station. [Figure 11] The ventral fillet station is shown. [Figure 12] Shows cutting being done by the dorsal fillet station. [Figure 13] The lifting structure is shown. [Figure 14] The band knife structure and abdominal plate are shown. [Figure 15] 1 shows the belly plate structure in the machine. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0057] With reference to Figure 1, the filleting machine 1 comprises a frame 2 carrying a conveying system arranged to transport a string of fish in a downstream direction indicated by arrow 3 from an infeed 4, through a processing station to an outfeed 5.

[0058] Each fish is conveyed through the machine and thus through a number of sequentially arranged processing stations. The processing stations may include filleting stations and trimming stations. In one example, the machine comprises a ventral filleting station, a ventral trimming station, a dorsal trimming station, a dorsal filleting station and a band knife filleting station configured to release the fillets from the ventral, dorsal and ventral bones and from the vertebral bones. The band knife arrangement including band pulleys 6 can be seen at the rear of the machine.

[0059] As defined in this specification, the height direction of the machine is the direction vertically upward from the legs 7 .

[0060] FIG. 2 shows that the fish 20 to be filleted is positioned so that the dorsal fin 21 points upwards and the front of the headless fish faces downstream.

[0061] The fish are gutted and the head of the fish is generally removed prior to introducing the fish into the machine. The tail 23 is generally retained.

[0062] FIG. 3 shows a fish having certain dimensions as defined herein.

[0063] The fish extends in a length direction indicated by arrow 30 from the front end 22 to the tail 23. The fish has a width from left to right side, indicated by arrow 31. The height of the fish is indicated by arrow 32 and defines the distance between the end of the dorsal edge 33 and the end of the ventral edge 34.

[0064] The dorsal part of the fish is that part extending upward from the vertebrae 35 to the edge of the dorsal part 33 of the fish. The ventral part of the fish is that part extending downward from the vertebrae 35 to the edge of the ventral part 34. The vertical midplane is a longitudinally extending vertical plane that passes through the middle of the vertebrae and intersects center-wise between the two fillets.

[0065] The fish shown is a salmon (Salmon serrata), a species of Actinopterygii in the Salmonidae family, although the machine can fillet other species of fish.

[0066] Upon entering the machine the fish is gutted, i.e. the abdomen is cut open and the intestines removed. The open abdomen 40 is shown in Figures 3 and 4, with line 37 indicating the dorsal fillet cut in Figure 3.

[0067] Figure 4 shows a cross section of a fish with an open abdomen 40 providing free left and right lateral edges of the ventral parts 41, 42 on either side of a vertical central plane. Figure 4 also shows conveyor belts 43, 44 engaging either side of the fish.

[0068] As the fish progresses through the machine 1 it passes through a number of stations and eventually the essentially boneless fillets are delivered to an outfeed 5 for e.g. further processing or packaging.

[0069] Figure 5 shows a detail of the infeed 4, which is formed as a chute. Figure 5 further shows stations 50 and 51. Station 50 has means for detecting the width of the fish. The width of the fish is determined by the rotation of plate 52, which is lifted by the fish lying on its side, as it is transported on belt 53 below the plate. The determined width is transmitted to computer control unit 54 and used in several processes.

[0070] The next station 51 is an in-feed system configured to receive and rotate the fish from a sideways orientation with the width dimension facing upwards to an upward orientation with the dorsal edge of the fish facing upwards. Figure 5 only shows a portion of the in-feed system, further details can be found, for example, in WO2018146203A1, which is incorporated herein by reference.

[0071] In the upward direction the fish is received by the conveying system of the machine.

[0072] The conveying system is shown in Figures 6-9 and comprises an endless belt on either side of a vertical central plane. The endless belt engages the fish and conveys it through the machine. The position of the fish can be determined by recording the progression of the endless belt. The endless belt is provided with a deflection means which encourages the endless belt to make firm contact with the fish being processed. Typically the surface of the endless belt is provided with a surface pattern, e.g. with spikes, to ensure a firm grip and prevent slippage between the belt surface and the fish.

[0073] Figure 6 shows the conveying system seen from above, showing the entrance gap where the fish is received from station 51. The gap is indicated by arrow 61. The exit gap 62 is where the fish fillets and skeleton leave the machine.

[0074] In figure 7 it is shown that the conveying system forms an upstream conveying section 70 and a downstream conveying section 71. The upstream conveying section 70 comprises a first endless belt 72 on one side of a vertical central plane and a second endless belt 73 on the opposite side of the vertical central plane.

[0075] The belt in the upstream section 70 extends between upstream pulleys 74, 75 and downstream pulleys 76, 77. The belt is driven by drive pulleys 78, 79.

[0076] The upstream pulley defines an entrance gap 61 shown in FIG. 6, ie, where fish can be received between the upstream pulleys.

[0077] The machine is equipped with an inlet clearance control device arranged to read the width of the fish detected at station 50 and to control the position of the upstream pulley by use of a servo motor 90, shown enlarged in FIG.

[0078] By varying the relative positions of the upstream pulleys to each other, the size of the inlet gap is actively varied by a servo motor controlled by the inlet gap controller to correspond to the width of the fish, thereby providing a predetermined clamping pressure from the belt to the fish.

[0079] The downstream conveying section forms a third endless belt 80 on one side of a vertical central plane and a fourth endless belt 81 on the opposite side of the vertical central plane. The third and fourth endless belts extend between upstream pulleys 82, 83 and downstream pulleys 84, 85 and are driven by drive pulleys 86, 87.

[0080] 8, an exit gap 62 is defined between downstream pulleys 84, 85 for delivering the whole piece of fish after it has been split into two fillets and a skeleton. The three pieces of fish are delivered to the exit gap between third and fourth endless belts 80, 81.

[0081] The machine is equipped with an outlet gap controller embedded in the computer control unit 54. The outlet gap controller is configured to read the detected width and control the position of at least one of the downstream pulleys 84, 85 by use of a servo motor 89. This allows the machine to apply a controllable clamping pressure from the belt to the fish at the delivery point, thereby reducing the risk of damaging the fillets.

[0082] 7 shows that the first and second endless belts, i.e. the belts of the upstream conveying section, extend at a first height, i.e. a first height in an upward direction, while the third and fourth endless belts, i.e. the belts of the downstream conveying section, extend at a second height, higher, i.e. in an upward direction.

[0083] One of the planar cut filleting stations between the infeed 4 and the outfeed 5 constitutes a ventral filleting station 100. The ventral filleting station is arranged to cut the fish along the ventral edge of the fish as it is being transported.

[0084] The other of the planar cutting fillet stations between the infeed 4 and the outfeed 5 constitutes a dorsal fillet station 110 arranged to cut the fish along the dorsal edge of the fish as it is being transported.

[0085] Generally, the dorsal fillet station is located downstream relative to the ventral fillet station.

[0086] The ventral filleting station is shown in Figure 10 and the dorsal filleting station is shown in Figure 11. Both filleting stations have a pair of rotating blade knives and functionally identical features are described with the same reference numerals.

[0087] The filleting station has a first cutting blade 101 disposed on one side of a vertical central plane. The first cutting blade is configured to cut fish while the first cutting blade rotates about a first axis of rotation 102.

[0088] A second cutting blade 103 is disposed on the opposite side of the vertical central plane and rotates about a second axis of rotation 104 that is angled relative to the first angle of rotation.

[0089] Both the dorsal and ventral fillet stations have a gap control structure that is partly embedded in the computer control unit 54 and partly constituted by a displacement motor 105 .

[0090] The gap control structure is configured to read the detected width of the fish and is configured to move the cutting blades relative to one another to vary the gap between the cutting blades The gap control structure is configured to make this adjustment while the fish is being transported through each filleting station, i.e. while the fish is being cut by the cutting blades.

[0091] The position of the cutting blades is varied by a displacement motor 105 in the form of a linear actuator which can move the blades towards or away from each other. During this movement, the blades 101, 103 are maintained at a fixed angle relative to the transport direction of the fish.

[0092] The filleting station further includes a rotation motor 106 disposed for each cutting blade for rotating the corresponding cutting blade.

[0093] As shown, the movement of the cutting blades is effected by individual linear actuators for each blade, so that each blade may move inward toward and outward from the other blade individually. However, the gap control structure is configured for both individual movement and synchronous movement in which both blades of a pair of blades move simultaneously toward or away from the other blade, i.e., symmetrically relative to the vertical center plane. During this movement, the angle of the circular blades remains at a fixed angle.

[0094] The translation axis for the linear motion is perpendicular to the circular blade, i.e. it moves the blade in the direction of the axis of rotation, but the axis of rotation is not parallel and therefore the inward and outward motions for adjusting the gap are not necessarily perpendicular to the conveying direction.

[0095] The displacement motor 105 and the rotation motor 106 are formed in the cutting unit, i.e. as one single component, with both the displacement motor and the rotation motor fixed to one and the same chassis 107. Both motors are therefore inelastically joined and can be mounted and removed from the machine as one single component without the need for adjustment between the motors.

[0096] The machine comprises four of these units, two units arranged opposite each other to form a dorsal fillet station and two units arranged opposite each other to form a ventral fillet station.

[0097] Each unit is reversibly fixed to the machine, for example by bolts, and wired to the machine at a plug interface. During servicing or repair of the machine, each of the four units can be independently removed, and when the plug interface is attached to the machine, the computer control unit 54 controls the units so that the desired gap can be created by use of the displacement motors 105 of one or both of the stations.

[0098] In one embodiment, the cutting blades 101, 103 are rotated by a drive shaft 108 that is rotatably supported within an outer tube 109. The drive shaft is shown in dotted lines as it is encased inside a protective shield 110 and is not visible on the assembled unit.

[0099] The outer tube 109 defines a bearing structure and rotatably fixes the blade to the machine. The displacement motor 105 moves the outer tube in the direction of the rotation axes 102, 104. To effect this movement, the outer tube 109 is slidably supported on the chassis 107, and the displacement motor may engage the outer tube 109, for example, via a spindle engagement or any other similar type of gear engagement. As the outer tube and the cutting blade move back and forth, the drive shaft 108 moves back and forth inside a protective shield 110 that is long enough to provide space for the lateral movement of the drive shaft. The rotation motor 106 is arranged to engage the drive shaft and rotate the drive shaft and the blade while the outer tube and the blade are moving laterally by use of the displacement motor 105. To effect this, the drive shaft may form a longitudinally extending tooth structure, and the rotation motor 106 may engage this tooth structure by means of a gear that may slide longitudinally along the tooth structure while the outer tube and the blade are moving laterally.

[0100] Figure 12 shows the result of the cut provided by the dorsal filleting station. The cut is indicated by the dark area 120 and runs along the entire length of the fish. Linear movement of the blades towards or away from each other changes the gap without affecting the angle of the cut. This is indicated by arrows 121.

[0101] The gap control structure adjusts the gap so that the slit in the dorsal side of the fish can vary over the length of the fish without affecting the cutting angle.

[0102] FIG. 13 shows a lifting structure 130 positioned to lift the fish and prevent the ventral filleting station from separating the ventral bones from the vertebrae.

[0103] The lifting structure 130 defines a plate which defines lifting points 131 located at the corners of the plate. The plate is fixed to a drive shaft 132 driven by a motor 133 so that the lifting points can follow a circumference indicated by the dotted line 134. The circumference lies in a vertical central plane.

[0104] As the lifting points rotate, they follow the sequence described below. Step 1) The fish enters the machine and the lifting point is below the level of the fish's vertebrae. Step 2) The fish enters the ventral fillet station and the lifting point rotates along the lower edge of the fish's vertebrae to a point where it engages and lifts the vertebral point. Step 3) The lifting point moves downstream while in contact with the vertebrae. In particular, the lifting structure may rotate at a speed coordinated with the speed of the transport structure so that the vertebrae point accurately follows the point on the fish that engages the fish. Step 4) After moving a certain distance downstream, the vertebral point disengages from the vertebral point and rotates to a waiting position to wait for the next fish in the series. Step 5) corresponds to step 1) and the sequence is repeated.

[0105] Figure 14 shows the band knife arrangement 140 of the machine. The band knife arrangement is located downstream relative to the filleting station and has two flexible rotating closed loop knife bands 141, 142 which rotate around pulleys not shown in Figure 14 but designated 6 in Figure 1.

[0106] The knife bands are positioned to make curved cuts on either side of the vertebrae while the fish is moving forward between the two belts.

[0107] A vertical central plane 143 extends centrally between the two knife bands.

[0108] The machine includes a pair of push-down nippers 144, 145 arranged to provide push-down pressure on the right and left side of the fish towards the two belts. The machine further includes a belly plate structure 146 as shown in FIG.

[0109] The abdominal plate structure has right and left abdominal plates 150, 151. The fish is transported to a position where the abdominal plates are between the free left and right side edges of the abdominal portions 41, 42. The right and left abdominal plates are on either side of a vertical central plane 143 and are positioned to press the abdominal edges of the fish away from each other against the compressive pressure from the nippers. This pressure from the abdominal plates positions the abdominal edges in a position where the band knives will sever the meat from the abdominal bones.

[0110] The abdominal plate is movable by an abdominal plate motor structure having individual abdominal plate arms 152 movable laterally relative to the vertical central plane 143 by motors 153. The motors are controlled based on the width of the fish detected at station 50. This allows the abdominal plate to be positioned very accurately, thus optimizing the yield by positioning the ventral edge in such a way that the band knife cuts the ventral bone from the fillet without cutting into the fillet. During this process, the bone is pressed towards the central plane on the outside of the bone while cutting along the bone. In this way, the fillet is released from the bone with a small amount of meat on the bone.

Claims

1. A machine (1) for filleting fish, said machine comprising: A fillet station (100, 110); a conveying system (70, 71) configured to convey the series of fish in a downstream direction (3) through the filleting station (100, 110) while each fish in the series is oriented with its dorsal side facing upwards and its left and right sides on either side of a vertical central plane; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with At least one of the filleting stations comprises: a first cutting blade (101) arranged on one side of said vertical central plane and configured to cut said fish while said first cutting blade rotates about a first axis of rotation (102); a second cutting blade (102) disposed on an opposite side of the vertical central plane and configured to cut the fish while the second cutting blade rotates about a second axis of rotation (104); a gap control structure configured to vary a gap between the first and second cutting blades based on the detected width of the fish while the fish is being cut; and The machine is a planar cutting fillet station comprising:

2. each planar cut fillet station is configured to maintain a fixed angle between the first cutting blade and the second cutting blade during the change in the gap; 2. The machine of claim 1.

3. the gap control structure is configured to vary the gap by linear movement of both cutting blades in an inward direction toward one another or in an outward direction away from one another; 3. A machine according to claim 1 or 2.

4. the gap control structure is configured to vary the gap by linear motion in a direction not perpendicular to the downstream direction; 4. The machine of claim 3.

5. the gap control structure is configured to vary the gap by linear motion of each of the first and second cutting blades in the direction of the corresponding axis of rotation.

2. The machine of claim 1.

6. The first axis of rotation is not parallel to the second axis of rotation.

2. The machine of claim 1.

7. one of the at least one filleting station forms a ventral filleting station arranged to cut the fish along a ventral edge of the fish; 2. The machine of claim 1.

8. one of the at least one filleting station forms a dorsal filleting station arranged to cut the fish along a dorsal edge of the fish; 2. The machine of claim 1.

9. the gap control structure is configured to vary the gap by symmetrical movement of both cutting blades relative to the vertical central plane; 2. The machine of claim 1.

10. the machine includes a lifting structure defining a rotatable lifting point along a circumference in the vertical central plane, the lifting point being configured during rotation to sequentially engage and lift a vertebral point along a lower edge of a vertebra of a fish in the series, move in the downstream direction while in contact with the vertebra, disengage from the vertebral point, and engage and lift a vertebral point along a lower edge of a vertebra of a next fish in the series.

2. The machine of claim 1.

11. the rotational speed of the lifting structure is synchronized with the conveying speed of the fish so that the lifting points move in the downstream direction in contact with the vertebral points without slippage between the lifting points and the vertebral points; 11. The machine of claim 10.

12. the conveying system forming at least one endless belt on one side of the vertical central plane and at least one endless belt on an opposite side of the vertical central plane, each of the endless belts extending between an upstream pulley and a downstream pulley, an inlet gap being defined between the upstream pulleys for receiving the string of fish between the endless belts, the machine further comprising an inlet gap controller configured to read the detected width and to control a position of at least one of the upstream pulleys relative to a position of the other upstream pulley to vary the inlet gap based on the width.

2. The machine of claim 1.

13. the conveying system having at least one endless belt on one side of the vertical central plane and at least one endless belt on an opposite side of the vertical central plane, each of the endless belts extending between an upstream pulley and a downstream pulley, an outlet gap being defined between the downstream pulleys for delivering the string of fish between the endless belts, the machine further comprising an outlet gap controller configured to read the detected width and to control a position of at least one of the downstream pulleys relative to a position of the other downstream pulley to vary the outlet gap based on the width, 2. The machine of claim 1.

14. the conveying system defines a first section having a first endless belt on one side of the vertical central plane and a second endless belt on an opposite side of the vertical central plane, the machine comprising a second section downstream of the first section having a third endless belt on one side of the vertical central plane and a fourth endless belt on an opposite side of the vertical central plane, the first section extending at a first height and the second section extending at a second height different from the first height; 2. The machine of claim 1.

15. The machine comprises: a band knife arrangement disposed downstream relative to the at least one filleting station and having two flexible rotating closed-loop knife bands arranged to provide curved cuts on either side of a vertebra of the fish as the fish advances between the two belts; a pair of pushing nippers arranged to provide pushing pressure on the right and left sides of the fish towards the two belts; an abdominal plate structure having right and left abdominal plates arranged to define an abdominal plate gap between the abdominal plates and arranged to press the right and left sides of the abdomen of the fish away from each other against the pushing pressure; a abdominal plate motor arrangement controlled based on the width of the fish for varying the abdominal plate gap between the abdominal plates according to the width of the fish; Equipped with 2. The machine of claim 1.

16. at least one of the planar cutting fillet stations has a height control structure configured to vary the height of the first cutting blade and the second cutting blade while the fish is being cut.

2. The machine of claim 1.

17. the machine comprises at least one height detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a height of the fish, and the height control structure is configured to vary the height of the first and second cutting blades based on the detected height of the fish.

17. The machine of claim 16.

18. the machine comprises at least one length detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a length of the fish, and at least one of the gap control structure and the height control structure is configured to vary the gap or the height of the first and second cutting blades based on the detected length of the fish.

17. The machine of claim 16.

19. the first cutting blade (101) is formed in a first cutting unit having at least a part of the gap control structure, the first cutting unit having a rotation motor arranged to rotate the first cutting blade and a displacement motor arranged to move the first cutting blade along the first rotation axis (102); 2. The machine of claim 1.

20. the first cutting unit has a drive shaft extending in the direction of the first rotation axis, the drive shaft being connected to the cutting blade (101), rotated by the rotation motor and displaced by the displacement motor; 20. The machine of claim 19.

21. the extension drive shaft is configured to permit linear displacement while rotational engagement between the drive shaft and the rotary motor is maintained during said displacement; 21. The machine of claim 20.

22. the rotational engagement includes engagement of a drive wheel of the rotary motor with an elongated cogwheel structure extending in the direction of the first rotational axis on an outer surface of the drive shaft; 22. The machine of claim 21.

23. the first cutting unit being reversibly detachable from the other machine as a single unit; 20. The machine of claim 19.

24. the second cutting blade (102) is formed in a second cutting unit which is identical to the first cutting unit or constitutes a mirror image of the first cutting unit in the central plane; 20. The machine of claim 19.

25. 13. A method of filleting fish by use of a machine according to claim 1, the method comprising moving the first and second cutting blades towards or away from each other without changing the angle between the blades, the blades moving while cutting the fish.

26. A machine (1) for filleting fish, said machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with its dorsal side facing upward and its left and right sides on opposite sides of a vertical central plane; at least one filleting station arranged to cut the fish while it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with The machine comprises a lifting structure defining a rotatable lifting point along a circumference in the vertical central plane, the lifting point being configured during rotation to sequentially engage and lift a vertebral point along a lower edge of a vertebra of a fish in the series of fish, move in the downstream direction while in contact with the vertebra, disengage from the vertebra, and engage and lift a vertebral point along the lower edge of the vertebra of a next fish in the series of fish.

27. A machine (1) for filleting fish, said machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with its dorsal side facing upward and its left and right sides on opposite sides of a vertical central plane; at least one filleting station arranged to cut the fish while it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with the conveying system forming an endless belt on one side of the vertical central plane and an endless belt on an opposite side of the vertical central plane, each of the endless belts extending between an upstream pulley and a downstream pulley, an inlet gap being defined between the upstream pulleys for receiving the string of fish between the first and second endless belts, the machine further comprising an inlet gap controller configured to read the detected width and to control a position of at least one of the upstream pulleys relative to a position of the other upstream pulley to vary the inlet gap based on the width.

28. A machine (1) for filleting fish, said machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with its dorsal side facing upward and its left and right sides on opposite sides of a vertical central plane; at least one filleting station arranged to cut the fish while it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with the conveying system having an endless belt on one side of the vertical central plane and an endless belt on an opposite side of the vertical central plane, each of the endless belts extending between an upstream pulley and a downstream pulley, an outlet gap being defined between the downstream pulleys for delivering the string of fish between the endless belts, the machine further comprising an outlet gap controller configured to read the detected width and to control a position of at least one of the downstream pulleys relative to a position of the other downstream pulley to vary the outlet gap based on the width.

29. A machine (1) for filleting fish, said machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with its dorsal side facing upward and its left and right sides on opposite sides of a vertical central plane; at least one filleting station arranged to cut the fish while it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with the conveying system forming an upstream conveying section and a downstream conveying section, each conveying section forming an endless belt on one side of the vertical central plane and another endless belt on an opposite side of the vertical central plane, the endless belt of one of the upstream and downstream sections extending at a higher height than the other of the upstream and downstream sections.

30. A machine (1) for filleting fish, said machine comprising: a conveying system configured to convey the series of fish in a downstream direction through at least one filleting station while each fish in the series is oriented with its dorsal side facing upward and its left and right sides on opposite sides of a vertical central plane; at least one filleting station arranged to cut the fish while it is being transported; at least one width detection mechanism disposed at an upstream position relative to the filleting station and configured to detect a width of the fish; It is equipped with The machine comprises: a band knife arrangement disposed downstream relative to the at least one planar cut fillet station and having two flexible rotating closed loop knife bands arranged to provide curved cuts on either side of a vertebra of the fish while the fish is advanced between the two belts; a pair of pushing nippers arranged to provide pushing pressure on the right and left sides of the fish towards the two belts; an abdominal plate structure having right and left abdominal plates arranged to define an abdominal plate gap between the abdominal plates and arranged to press the right and left sides of the abdomen of the fish away from each other against the pushing pressure; a abdominal plate motor arrangement controlled based on the width of the fish for varying the abdominal plate gap between the abdominal plates according to the width of the fish; The machine further comprises:

Images