Device for cutting the stems of a harvested mushroom

Abstract

Device for cutting the stipe of a harvested mushroom, comprising: - A knife blade connected to a rotation shaft, rotatably mounted by means of rotation of said shaft around an axis of rotation coinciding with the centre of the shaft, the knife having a cutting edge that extends from the shaft along a straight or curved path with at least one directional component in the radial direction of the axis; - A drive device for driving the shaft; - A control device for the drive, configured for: - Discontinuously driving the shaft, to each time turn a maximum of between one and one and three quarter full revolutions from a rest position and preferably to turn the shaft about one and a quarter revolutions from the rest position; - Returning the shaft to the rest position when exceeding a full revolution. - Subsequently stopping the shaft at the rest position.

Description

[0001] Device for cutting the stems of a harvested mushroom

[0002] The present invention relates to a device for cutting the stems of harvested mushrooms.

[0003] Mushrooms are harvested by cutting their stipe from the substrate they are grown on.

[0004] Commonly, this is a layer of compost with casing soil. The harvesting may be done manually or in an automated matter, as described in International patent application PCT / EP2024 / 062359 by the same applicant. In both cases, the mushroom stipe may need to be cut again, in orderto obtain a mushroom that is suitable to be presented in a consumer package, or to be further processed for consumption.

[0005] It is known in the art to cut mushroom stipes during conveyance of the mushrooms on a harvesting conveyor. While the stipes protrude through holes in the conveyor, they are cut by a knife that is configured for cutting all stipes at a predetermined distance below the conveyor surface.

[0006] However, arranging mushrooms on a harvesting conveyor still requires manual labour in most cases, and the predetermined distance with respect to the conveyor surface may be set at an average optimum value, but as a result, it is not necessarily the best setting for each individual mushroom.

[0007] It is also known in general to use a disc-shaped knife for cutting mushroom stipes. However, such knives have an impact on the stipe in the direction of the speed of their circumferential edge. This impact may cause the mushroom to tilt during the cutting of the stipe, or require a grabbing force to avoid the tilting, which force causes damage to the mushroom.

[0008] It is therefore a goal of the present invention, to provide a device for cutting the stems of harvested mushrooms that takes away the disadvantages of the prior art. More in particular it is a goal of the present invention to provide a device for cutting mushrooms each at an individual, optimised way. It is a further goal of the present invention to provide a useful alternative to the prior art.

[0009] Forthat purpose, the present invention proposes a device for cutting the stipe of a harvested mushroom, comprising:

[0010] A knife blade connected to a rotation shaft, rotatably mounted by means of rotation of said shaft around an axis of rotation coinciding with the centre of the shaft, the knife having a cutting edge that extends from the shaft along a straight or curved path with at least one directional component in the radial direction of the axis;

[0011] A drive device for driving the shaft. Contrary to a disc-shaped knife, a knife having a cutting edge that extends from the shaft along a straight or curved path with at least one directional component in the radial direction of the axis allows the mushroom to be brought in the cutting plane of the knife in a direction opposite to the momentary direction of the knife at the moment the knife touches the mushroom stipe. The cutting edge of the knife then cuts the stipe in a radial direction of the stipe. In an embodiment, wherein the mushroom is moving while its stipe is cut, the cutting direction may me essentially or exactly opposite to the direction of movement of the mushroom.

[0012] To avoid the mushroom stipe being hit by the knife twice, the knife may extend in only one direction from its axis, or in other words be a single knife, nit extending to both (or more) sides of the axis.

[0013] It is also possible that a mushroom is first positioned in a cutting position and is held still there without further movement. The device according to the invention may therefore further comprise:

[0014] A control device for the drive, configured for:

[0015] Discontinuously driving the shaft, to each time turn a maximum of between one and one and three quarter revolutions from a rest position and preferably to turn the shaft about one and a quarter revolutions from the rest position;

[0016] Returning the shaft to the rest position when exceeding a full revolution. Subsequently stopping the shaft at the rest position.

[0017] By discontinuously driving the shaft and therewith the knife, the device according to the invention allows to position an individual mushroom in a cutting plane described by rotation of the knife, being the circular surface through which the knife moves. As the knife makes less than two revolutions, the mushroom can be positioned at a cutting location where the cutting edge of the knife passes only once.

[0018] Returning the shaft to the rest position may therefore be done in opposite rotary direction of the rotary direction while cutting. The knife may have a limited width in a tangential direction, in order to leave space for positioning mushroom stipes in the cutting plane. In particular, the knife may protrude in only one direction and at only one side from the shaft. Preferably the knife has a surface that is less than 25% of the cutting plane and preferably less than 10%. The knife preferably extends over less than 90 degrees of the cutting plane and more preferably less than 45 degrees. The control device may be configured to achieve a speed progression wherein the speed increases to a maximum speed when rotating the blade and then decreases again to standstill, in particular accordingto a progression that is built up from a ramp-up and a ramp-down. This speed progression leads to the highest possible peak speed, which occurs at the instant between the ramp-up and the ramp down. The location of the knife at that instant may be selected as a cutting position for a mushroom, since the best cut is made at the highest speed. The control device may be configured to build up the speed to a maximum of at least 3000 rpm, preferably to a maximum of at least 4000 to 5000 rpm and more preferably around 4500 rpm. It has been determined that at this speed, in particular with knife specifications as provided further on, a sharp cut can be obtained, without having an impact that substantially moves the mushroom.

[0019] In an embodiment, on a side facing away from the direction in which the blade extends the shaft is provided with a counterweight, such as a thickening, for balancing the shaft. Such counterweight may be configured and / or dimensioned to have the same moment as the knife. The device accordingto the invention may comprise a mushroom gripping and moving means, configured for gripping a mushroom at or under the cap of the mushroom, such that the end of the stipe of the mushroom is accessible, and for positioningthe mushroom in a cutting plane described by rotation of the knife, being the circular surface through which the knife moves. The gripping means of such device may comprise a vacuum suction cap, clamping means, hook means or other lifting means, and be configured and / or adapted to pick individual mushrooms from a harvesting conveyor belt in case it is used in combination with manual harvesting or a picking robot that places harvested mushrooms in a harvesting belt, which is a conveyor belt with holes for mushroom stipes, or from a cloth or foil which may be used in combination with automated harvesting methods, as described in the above mentioned international patent application.

[0020] As the knife extends in a radial direction from the shaft, the cutting plane is disc-shaped.

[0021] The control device may be configured to control the gripping and moving means, and is further configured to place a mushroom stipe to be cut at a position in the cutting plane that is located at an angle of between 120 and 270, more particularly between 180 and 240 degrees and even more particularly around 225 degrees around the axis of rotation, from the rest position. The cutting position may be chosen to be at the position where the knife has a high or preferably the highest speed, which latter is at the angular position where the speed is altered from a ramp-up to a ramp-down. Depending on the amount of turns (between one and one and three quarter turns) this may be halfway the total number of turns, as will be elucidated into more detail with reference to the figures.

[0022] The control device may further be configured to control the gripping and moving device for placing it at a position in the cutting plane where the rotating knife has its maximum rotational speed.

[0023] The mushroom gripping and moving means may comprise a robot arm. Such robot arm may carry a vacuum suction cap, clamping means, hook means or other lifting means. The robot arm may further be used and configured to place the mushroom in a mushroom container after its stem is cut. This may for instance be done in the way described in the Dutch patent NL2030561 by the same applicant, which is hereby incorporated by reference.

[0024] Herein it is explained that a transport device for moving mushrooms from at least one harvesting location to a packaging location - in the present application referred to as mushroom gripping and moving means - may comprise a conveyor designed to lift one or more mushrooms simultaneously and measure their individual weight. Such a conveyor may comprise a robot, or an XY or XYZ conveyor; an assembly of linear actuators capable of achieving movements in two orthree dimensions.

[0025] The conveyor may be designed to pick up one or more mushrooms from the harvesting conveyor and, after measuring, return the mushrooms to the harvesting conveyor, particularly at the same location on the harvesting conveyor. Harvesting conveyors are often equipped with holes, which define precise mushroom locations. By weighing the mushrooms and then returning them to the packaging location, the weight of the mushrooms on their way to the packaging location is known, allowing for advance calculation of which selection of individual mushrooms should be added to a ready-made package and which mushrooms should be buffered. In an alternative embodiment, however, the conveyor is designed to pick up one or more mushrooms from the harvesting belt and, after measurement (directly, i.e., without replacing them), place the one or more mushrooms in a buffer and / or packaging.

[0026] From the above, itwill be clearthat a transport device accordingto the present invention can comprise a series of one or more devices, such as picking or harvesting belts, chains, conveyors such as robots, particularly linear XYZ robots, and other devices.

[0027] When placingthe mushroom with the cut stem in a container, the mushroom gripping and moving means may be configured to control the positioning and placement of the container in the mushroom container in a way as described in the Dutch patent publication NL2022795B1 , which is herein incorporated by reference.

[0028] As the mushroom gripping and moving means already takes a mushroom from a harvesting conveyor or a conveyor on which it is deposited when it is selected for cutting its stem, there is a synergy when the same mushroom gripping and moving means position the mushroom in the containerwhere it is to be delivered in the end, directly.

[0029] Furthermore, as described below, the present invention may comprise an optical recognition device. This device may be used to determine a cutting position for the stem, but also to gather information with respect to any relevant optical feature of the mushroom, such as its size, colour or shape, and based on this information a position and / or orientation in a mushroom container may be determined. Data gathered in the same way from mushrooms already positioned in the same or another container may be taken into account. Several mushroom containers may be filled simultaneously, as to create an optimal or desired filling of the containers.

[0030] The invention also relates to a device for cutting the stipe of a mushroom in any of the ways and with any of the described (combination of) features above, also configured to place the mushroom in a container once its stem is cut, in particular in a way described above.

[0031] The device according to the invention may further comprise an optical recognition device, such as a camera system, for monitoring the stipe of a mushroom, before or during gripping and moving a mushroom held by the gripping and moving device, wherein the control device is configured to determine a cutting position on the stipe of the mushroom stiped on information provided by the optical recognition device, and is configured to control the gripping and moving device to cut the mushroom with the cutting position in the cutting plane.

[0032] The optical recognition device may be coupled to the gripping and moving device or be placed and / or directed at the mushroom bed or at the position of the knife.

[0033] The control device may be configured to determine the cutting position on the stipe of the mushroom on at least one of the following criteria:

[0034] - The shape of the stipe;

[0035] - The height to which there are contaminants such as casing soil and / or compost on the stipe; or - The ratio between the cap diameter or cap height and the stipe length. The control device may be configured to position the mushroom with its entire stipe just in the extreme range of the cutting plane by the mushroom gripping and moving means.

[0036] A knife for use in a device according to the invention may have a blade length from the axis of rotation to an end of the blade is between 6 and 10 cm, and in particular between 7 and 9 cm, and more in particular about 8 cm. Such blade may decrease in width from the axis of rotation, and / or taper, and / or be substantially scythe-shaped, and / or substantially have the shape of the black or white part of a yin and yang shape.

[0037] The blade may have a cutting angle of between 5 and 10, and in particular between 6 and 7 and more in particular about 6.5 degrees.

[0038] The invention will now be elucidated into more detail, with reference to the following figures. Herein:

[0039] Figure 1 shows a perspective view of a device according to the invention;

[0040] Figure 2 shows a detail of a knife blade fora device according to the invention;

[0041] Figure 3 shows a schematic overview of the use of a device according to the invention; and

[0042] Figure 4 shows a speed curve during use of a device according to the invention.

[0043] Figure 1 shows a device 1 for cutting the stipe 8 of a harvested mushroom 9, comprising a knife blade 2 connected to a rotation shaft 3, rotatably mounted by means of rotation of said shaft around an axis of rotation 4 coinciding with the centre of the shaft 3, the knife having a cutting edge 5 that extends from the shaft along a straight or curved path 6 with at least one directional component in the radial direction R of the axis 4. The device 1 may further comprise a drive device (not shown) for driving the shaft 3 and a control device (not shown) for the drive, configured for discontinuously driving the shaft 3, to each time turn a maximum of between one and one and three quarter full revolutions F from a rest position A (visible in figure 3 ) and preferably to turn the shaft 2 about one and a quarter revolutions from the rest position A, followed by returning the shaft 3 to the rest position when exceeding a full revolution and subsequently stopping the shaft 3 at the rest position. The device 1 further comprises mushroom gripping and moving means 11 , configured for gripping a mushroom 9 at or under the cap 7 of the mushroom 9, such that the end of the stipe 8 of the mushroom 9 is accessible, and positioning the mushroom 9 in a cutting plane P described by rotation of the knife 2, being the circular surface through which the knife 2 moves. The drive may also be configured for moving the mushroom through the cutting plane. In that case it is not necessary to start and stop the knife, although this combination is thinkable. Figure 2 shows a knife 2 according to the invention wherein the blade length Lfrom the axis of rotation 4 to an end of the blade is between 6 and 10 cm, and in particular between 7 and 9 cm, and more in particular about 8 cm. The blade 12 decreases in width W in a radial R direction X away from the axis of rotation 4, and / or tapers, and / or is substantially scythe-shaped, and / or has substantially the shape of the black or white part of a yin and yang shape. The blade 12 has a cutting angle of between 5 and 10, and in particular between 6 and 7 and more in particular about 6.5 degrees.

[0044] Figure 3 shows how a mushroom 9 stipe 8 to be cut is positioned at a position E in the cutting plane P where the rotating knife has its maximum rotational speed. In this example, the rest position may be at position A, and the control device may be configured for rotating the knife 2 one and a quarter turns, so that a tip 10 of the knife 2 starts at position A and then passes positions B and C while its speed V ramps up, before it reaches its maximum speed at position E, that is located at an angle of 225 degrees around the axis of rotation, from the rest position A, and then the speed is ramped down while the tip 10 passes positions D and A. It stops at position B and then returns to position A, rotating in an opposite direction from B to A. It is also possible that the knife is continuously driven for rotation. In either case it is also thinkable that the mushroom is moved through the cutting plane, in a direction X which is preferably essentially or exactly opposite to the momentary direction Y in which the part of the knife that hits the mushroom moves.

[0045] The control device is configured to position the mushroom 9 with its entire stipe 8 precisely in the extreme range Z of the cutting plane P by the mushroom gripping and moving means 11. Figure 4 shows how the control device is configured to achieve a speed progression wherein the speed V (which is the speed of the tip 10 of the knife 2) increases to a maximum speed when rotating the blade and then decreases again to standstill, in particular according to a progression that is built up from a ramp-up and a ramp-down. In the example shown, the maximum speed is 4500 rpm. As the knife 2 rotates 450 degrees, it has to rotate back with negative speed to rest position A.

[0046] The embodiments as described are examples only and do not limit the scope of protection of the following claims.

Claims

Claims1. Device for cutting the stipe of a harvested mushroom, comprising:A knife blade connected to a rotation shaft, rotatably mounted by means of rotation of said shaft around an axis of rotation coinciding with the centre of the shaft, the knife having a cutting edge that extends from the shaft along a straight or curved path with at least one directional component in the radial direction of the axis;A drive device for driving the shaft.

2. Device accordingto claim 1, comprising:A control device for the drive, configured for:Discontinuously driving the shaft, to each time turn a maximum of between one and one and three quarter full revolutions from a rest position and preferably to turn the shaft about one and a quarter revolutions from the rest position;Returning the shaft to the rest position when exceeding a full revolution. Subsequently stopping the shaft at the rest position.

3. Device accordingto claim 2, wherein the control device is configured to achieve a speed progression wherein the speed increases to a maximum speed when rotating the blade and then decreases again to standstill, in particular according to a progression that is built up from a ramp-up and a ramp-down.

4. Device accordingto claim 2 or 3, wherein the control device is configured to build up the speed to a maximum of at least 3000 rpm, preferably to a maximum of at least 4000 to 5000 rpm and more preferably around 4500 rpm.

5. Device accordingto one of the preceding claims, wherein the shaft on a side facing away from the direction in which the blade extends is provided with a counterweight, such as a thickening, for balancing the shaft.

6. Device accordingto any of the preceding claims, comprisinga mushroom grippingand moving means, configured for gripping a mushroom at or under the cap of the mushroom, such that the end of the stipe of the mushroom is accessible, and positioning the mushroom in a cutting plane described by rotation of the knife, being the circular surface through which the knife moves.

7. Device accordingto claim 6, wherein the mushroom grippingand moving means are configured for bringing the mushroom in the cutting plane of the knife in a direction opposite to the momentary direction of the knife at the moment the knife touches the mushroom stipe.

8. Device accordingto claim 7, wherein the mushroom grippingand moving means are configured for moving the mushroom is moving while its stipe is cut, wherein the direction of movement of the mushroom is essentially or exactly opposite to the cutting direction.

9. Device accordingto any of claims claim 6 to 8, wherein the control device is configured to control the gripping and moving means, and is further configured to place a mushroom stipe to be cut at a position in the cutting plane that is located at an angle of between 120 and 270, more particularly between 180 and 240 degrees and even more particularly around 225 degrees around the axis of rotation, from the rest position.

10. Device accordingto any of claims claim 6 to 9, wherein the control device is configured to control the gripping and moving device for placing it at a position in the cutting plane where the rotating knife has its maximum rotational speed.

11. Device according any of claims claim 6 to 10, wherein the mushroom grippingand moving means comprises a robot arm.

12. Device accordingto any of claims 6-11 , comprising an optical recognition device, such as a camera system, for monitoring the stipe of a mushroom, before or during gripping and moving a mushroom held by the gripping and moving device, wherein the control device is configured to determine a cutting position on the stipe of the mushroom stiped on information provided by the optical recognition device, and is configured to control the gripping and moving device to cut the mushroom with the cutting position in the cutting plane.

13. Device accordingto any of claims 6-11 , wherein the optical recognition device is coupled to the gripping and moving device or is placed and / or directed at the mushroom bed or is positioned at the knife.

14. Device accordingto claim 12, wherein the control device is configured to determine the cutting position on the stipe of the mushroom stiped on at least one of the following criteria: - The shape of the stipe;- The height to which there are contaminants such as casing soil and / or compost on the stipe; or - The ratio between the cap diameter or cap height and the stipe length.

15. Device according to one of claims 6-14, wherein the control device is configured to position the mushroom with its entire stipe precisely in the extreme range of the cutting plane by the mushroom gripping and moving means.

16. Device according to one of the preceding claims, wherein the blade length from the axis of rotation to an end of the blade is between 6 and 10 cm, and in particular between 7 and 9 cm, and more in particular about 8 cm.

17. Device according to any of the preceding claims, wherein the blade decreases in width from the axis of rotation, and / or tapers, and / or is substantially scythe-shaped, and / or has substantially the shape of the black or white part of a yin and yang shape.

18. Device according to any of the preceding claims, wherein the blade has a cutting angle of between 5 and 10, and in particular between 6 and 7 and more in particular about 6.5 degrees.

19. Mushroom harvesting device, comprisinga device accordingto any of the preceding claims.

20. Device for cutting the stipe of a mushroom, in particular accordingto any of the preceding claims 1-18, also configured to place the mushroom in a container once its stem is cut.

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