DESCRIPTION:

Technical field of the invention

The invention relates to a knife cassette for use in a cutting device for cutting leaves from flowers of plants, comprising: a frame, and a knife roller mounted in the frame and which comprises: a rotation shaft, and at least two knives attached to the rotation shaft and provided with cutting edges spaced from the rotation shaft and extending between the ends of the rotation shaft, and a further knife roller which is also mounted in the frame, the two knife rollers being parallel to each other, wherein the knives are substantially closed between the rotation shaft and the cutting edges, and during rotation the knife rollers rotate in opposite directions.

The rotation shaft is formed, for example, by a tube that is rotatable about an shaft fixed to the frame or by a shaft that is rotatably mounted in the frame. The cutting edges of the knives do not extend perpendicular to the rotation shaft, but in the longitudinal direction of the rotation shaft, whereby the cutting edges need not be straight.

Background of the invention

A cutting device provided with a knife cassette according to the preamble of claim 1 is known from US 2019/388902 Al. Furthermore, US 8 757 524 B2 discloses a cutting device in which the knife roller is located in a closed housing which is provided with a first opening through which the leaves to be cut enter and a second opening into which the cut leaves are discharged from the housing. Suction means are connected to the second opening for sucking the leaves to be cut off into the housing via the first opening so that they can be cut off better and for sucking the cut-off leaves out of the housing via the second opening.

Summary of the invention

An object of the invention is to provide a knife cassette of the type described in the preamble with which leaves of flowers and plants can be cut off more quickly and efficiently. To this end, the knife cassette according to the invention is characterized in that the knife rollers are present at a distance which is less than twice the radial distance from the rotation shaft to the cutting edge, so that the knives mesh with each other.

By making the knives substantially closed and allowing them to rotate into each other, a pumping action occurs whereby air is sucked in on one side and air is blown out on the other side. This pumping action sucks the leaves towards the knives and blows away the cut leaves. By interlocking the knives, the pumping effect is considerably increased so that leaves of plants can be cut off in an even more efficient manner. As a result, it is not necessary to use a closed housing and extraction means can be omitted.

The knives are preferably completely closed between the rotation shaft and the cutting edges, so that a maximum suction effect occurs during rotation and the parts to be cut off (leaves of plants) are sucked towards the knives.

The cutting edges of the knives preferably extend in an imaginary cylindrical shell with a center line that coincides with that of the rotation shaft. As a result, an imaginary cylinder shell forms the plane in which the knives move, so that the position of the cutting edges in relation to the rotation shaft is clear.

The cutting edges of the knives can extend helically (with a large pitch) in the imaginary cylinder shell. Preferably, however, the cutting edges of the knives extend parallel to the rotation shaft, so that the knife rollers are simpler to manufacture and a better pumping effect occurs.

An embodiment of the knife cassette according to the invention is characterized in that the frame comprises a housing provided with a first opening through which parts to be cut off enter and a second opening into which cut-off parts are discharged from the housing, with the housing outside this opening being substantially closed. By using a housing, the cut leaves can be discharged in a targeted manner. In order to ensure that the knife rollers rotate synchronously, a gear wheel is preferably arranged on each rotation shaft at one end of the knife cassette, and the two gear wheels on the rotation shafts mesh with each other.

In order to be able to repair the knives easily and quickly in the event of damage (deformation, bending) of the knives, the knives are preferably manufactured substantially from memory metal. Alloys often used as memory metal (shape memory alloy) are copper-zinc-aluminium alloys. Preferably, however, a nickel-titanium alloy (Nitinol) is used as memory metal for the knives, despite the fact that this is much more expensive than the more common copper-zinc-aluminium alloys. Advantage of Nitinol as memory metal compared to other memory metals is that it is relatively strong, so that objects made from it can be made thin.

In order to further reduce the risk of damage (deformation, bending) of the knives, an embodiment of the knife cassette is characterized in that the knives are flexible.

The invention also relates to a cutting device for cutting leaves from flowers of plants, comprising: a wall provided with through holes, provided with a working side over which products to be processed during operation are moved, as well a knife roller provided with at least two knives, each provided with a cutting edge that rotates close to the wall during operation, and a drive for rotating the knife roller, which cutting device comprises at least one knife cassette according to the invention as described above, of which said knife roller forms part.

An embodiment of the cutting device according to the invention is characterized in that the knife rollers are rotated by the drive at, at least 1,500 revolutions per minute and preferably at, at least 3,000 revolutions per minute. Due to the high speed, plant parts are divided by a combination of cutting and beating in half, so that the knives become less dirty than when plant parts are completely cut off because there is almost no adhesion of resin.

In a further embodiment, the wall is a drum wall of a drum which is rotated during operation by a further drive, the knife rollers extending parallel to the drum. Preferably, a number of knife cassettes are distributed over part of the circumference of the drum in order to cut off the leaves of a plant in a shorter time and thus increase the efficiency. In another embodiment, the wall is a stationary plate, wherein during operation the plants to be processed must be moved across the plate in a direction perpendicular to the knife rollers. Preferably, in the direction in which the plants are moved over the plate, a number of knife cassettes, parallel to each other, are present one behind the other in order to increase the efficiency. The knife cassettes can herein be present at a mutual distance from each other or, if the size of the plate is limited, be present directly next to each other. The plate can hereby extend horizontally or extend obliquely or straight upwards. Two plates with the working side facing each other can also be present at a distance from each other, the plants to be processed being moved between the plates during operation.

Brief description of the drawings

The invention will be explained in more detail below on the basis of drawings in which exemplary embodiments of the knife cassette and the cutting device according to the invention are shown. In the drawings:

Figure 1 shows a first embodiment of the knife cassette according to the invention in exploded view;

Figure 2 shows a cross-section of the knife cassette shown in Figure 1;

Figure 3 shows a number of the knife cassettes shown in Figure 1 next to a drum of a cutting device;

Figure 4 shows a second embodiment of the knife cassette according to the invention next to a drum of a cutting device;

Figure 5 shows a third embodiment of the knife cassette according to the invention in an exploded view;

Figure 6 shows a fourth embodiment of the knife cassette according to the invention in cross-section;

Figure 7 shows a first embodiment of a cutting device provided with three knife cassettes shown in figure 1 as seen on the drive for the knives;

Figure 8 shows the cutting device shown in figure 75 as seen on the drive for the drum;

Figure 9 shows a second embodiment of a cutting device provided with three knife cassettes shown in figure 1 in top view; and Figure 10 shows the cutting device shown in figure 9 in section along line X-X.

Detailed description of the drawings

Figure 1 shows a cross-section of a first embodiment of the knife cassette according to the invention. The knife cassette 101 has a frame 103 of which two carriers 104 are shown. Two bearings 106 are attached to each carrier. The two carriers 104 are connected to each other via a connecting construction, which is not shown. The knife cassette 101 further has two knife rollers 105 parallel to each other and each having four knives 109. The knives 109 are mounted on a rotational shaft 107, the ends of which are journalled in the bearings 106. At one end, the rotational shafts 107 pass through the bearings 106 and gears 108 are mounted on the ends. These gears 108 mesh with each other so that the knife rollers 105 rotate in opposite directions.

In figure 2 the knife cassette 101 is shown in cross-section. The knives 109 are each provided with a cutting edge 111 which extends parallel to the rotational axis at a distance from the rotation shaft 107. Between the cutting edge 111 and the rotation shaft 107, each knife 109 is closed, so that the knife rollers 105, during rotation, have a suction action on one side and a blowing action on the opposite side. The knife rollers 105 are spaced apart less than twice the radial distance from the rotation shaft 107 to the cutting edge 111, so that the knives 109 rotate into one another and the suction effect is increased.

In Figure 3, a number of knife cassettes 101 are shown next to a rotating drum 7 of a shearing device during cutting of leaves from a plant 121. The drum 7 has a wall formed by parallel spaced bars so that the leaves of the plants 121 can protrude through the gaps between the bars to be cut off while passing the knife cartridges 101.

Figure 4 shows the drum 7 with the knife rollers 105 in cross-section. In this second embodiment of the knife cassette according to the invention, the knife cassette 101a has a number of pairs of knife rollers 105 which are present in a housing 113. This housing 113 forms part of the frame. The carriers 104 are herein attached to end walls 113a of the housing. The side wall 113b of the housing extending between the end walls forms a receptacle for the cut leaves. The housing 113 is open on the drum 7 side. This side forms a first opening 115 through which the leaves of the plant protrude into the housing 113. The side wall 113b funnels to a second opening 117 through which cut leaves are discharged from the housing 113. Outside these two openings, the housing 113 is closed.

Figure 5 shows a third embodiment of the knife cassette 101b according to the invention. In this knife cassette 101b, the knife rollers 105b are provided with straight instead of curved knives 109b. The knives 109b herein extend radially on the rotation shaft 107b and during operation parts of the plants are more knocked off than cut off by the cutting edges 11 lb.

Figure 6 shows a fourth embodiment of the knife cassette 101c according to the invention. This knife cassette 101c is also provided with a housing 113c with a first opening 115c through which the leaves of the plant protrude into the housing 113c and a second opening 117c through which cut leaves are discharged from the housing 113c. Outside of these two openings, the housing 113c is closed to obtain a better pumping effect.

Figures 7 and 8 show a first embodiment of the cutting device according to the invention for cutting leaves from plants. The cutting device 1 has a box 3 in which a frame 5 is arranged. In the frame 5 there is a rotatable drum 7 into which the plants to be treated are to be placed. The drum 7 has two rings 9 and 11 spaced apart, one at each end of the drum 7. The drum 7 also has a number of elongate wall elements, which at their ends are attached to the rings 9 and 11 and extend between the rings 9 and 11 in a direction parallel to the longitudinal axis of the drum 7. The wall elements are distributed over the circumference of the drum 7 and are spaced apart and form the wall 13 of the drum 7. During operation, the leaves to be cut protrude through the openings present between the wall elements. In this embodiment, the wall elements are formed by rods with a round cross-section with a diameter of 1 or 1.5 mm.

The cutting device 1 furthermore has three knife cassettes 101, see figure 8, which are present under the drum 7. The knife rollers of the knife cassettes are present close to the wall 13 of the drum 7 so that the cutting edges of the knives rotate close to the outside of the drum 7 during operation.

The cutting device 1 furthermore has first rotation means 19 for rotating the drum 7 about the longitudinal axis, see in particular figure 8. These first rotation means 19 have an electric motor 51 which, via a belt 53, drives a gear wheel 55 which meshes with a teeth present in one of the rings 11. Furthermore, the cutting device 1 has second rotation means 25 for rotating the knife rollers, see figure 8. These second rotation means 25 also have an electric motor 61 which, via a belt 63, drive pulleys 65 which are mounted on one of the rotation shafts of the knife rollers.

The ring 9 of drum 7 is loose on rolls (not visible in the figures) and the ring 11 of drum 7 is loose on two gears 55 and 59, see figure 8. The drum 7 can thus move upwards out of the cutting device can be taken out by opening a cover on top of the frame. To easily remove the drum 7 from the cutting device the drum is preferably made firm.

The cutting device 1 furthermore has adjusting means 41 with which the distance between the knife rollers and the longitudinal axis of the drum 7 can be adjusted. The carriers 104 of the bearings for the rotation shafts of the knife rollers are present on carriages 45. The slides 45 are movable in a direction radial to the longitudinal axis of the drum 7. The position of the slides 45 and thus the distance from the knives to the wall 13 of the drum 7 can be adjusted by adjusting screws 47.

Figures 9 and 10 show a second embodiment of the cutting device according to the invention for cutting leaves from plants. In this cutting device 71, the wall is formed by a straight plate 73 provided with slots 75. Three knife cassettes 101 are located below the plate, each of which has two knife rollers 105 provided with knives 109. The knives 109 are mounted on rotation shafts 107 which are mounted in bearing blocks 77. The distance between the rotation axes 107 is less than twice the distance from the cutting edges 111 of the knives 109 to the rotation axes 107, so that the knife rollers mesh with each other.

The plants to be processed must herein be moved transversely to the knife rollers 105 over the plate 73, with upright side walls 79 providing guidance. Due to the suction action of the counter-rotating high-speed knife rollers 105, the leaves are sucked through the slots 75 and are cut off better.

Although the present invention is elucidated above on the basis of the given drawings, it should be noted that this invention is not limited whatsoever to the embodiments shown in the drawings. The invention also extends to all embodiments deviating from the embodiments shown in the drawings within the scope of the invention defined by the appended claims.