AN IMPLEMENT FOR DISPLACING CROP LYING ON THE SOIL

Abstract: An implement for displacing crop lying on the soil, said implement comprising at least one rake member which is driven so as to be rotatable about an upwardly orientated axis and which is provided with one or more outwardly extending arms (18) pivoting in upward direction about one or more pivotal axes (19), the ensemble of one or more arms (18) and one or more tines (25, 26) having such a centre of gravity (Z) that, when the implement is operative, the resultant of the gravitational and the centrifugal force moves one or more arms (18) with one or more tines (25, 26) towards the ground.

Description: AN IMPLEMENT FOR DISPLACING CROP LYING ON THE SOIL The invention relates to an implement for displacing crop lying on the soil, said implement comprising at least one rake member which is driven so as to be rotatable about an upwardly orientated axis and which is provided with one or more outwardly extending arms that are pivotable in upward direction about one or more pivotal axes, which arms are provided with one or more outwardly extending tines that are pivotable about one or more pivotal axes, while, in the transport position, one or more tines of one or more arms are pivoted downwards . Such an implement is described in the Dutch patent application 7607884. The known machine is provided with arms carrying tines at their free ends. The arms consist of straight hollow box girders to which the tines are fitted, which tines are capable of pivoting upwards about pivotal axes during operation. This construction has proved to function less effectively, especially on uneven soils. The invention aims at improving this machine. In accordance with the invention, the ensemble of one or more arms and one or more tines have such a centre of gravity that, when the implement is operative, the resultant of the gravitational and the centrifugal force moves one or more arms with one or more tines towards the ground. By means of the measures of the invention it is achieved that deviating movements of the tines caused by unevennesses in the soil are adjusted more quickly. As a result thereof the tines always move close along the ground, also in case of unevennesses in the soil. The arms and tines of the known machine can be brought into a transport position by an upward pivoting movement of the arms and a downward pivoting movement of the tines. The rake member has a conical housing which is made of plate material and to which the arms are fastened. This construction is relatively heavy and, besides, offers no protection to the arms in the folded up position. According to a further aspect of the invention, the rake member is provided with a frame with one or more arms that pivot into the transport position in upward direction about one or more pivotal axes. In this manner there can be obtained a lighter frame and a better protection of the arms . For the purpose of bringing the machine of the known construction into the transport position, the arms and the tines pivot upwards and are locked by means of hooks . According to a further aspect of the invention, the rake member is provided with a screen disposed around the rake member and located above the arms . By this measure there can be attained a threefold purpose, i.e. that the tines are stored under the screen in the transport position and that no separate locking means are required, the screen furthermore serving as a guide member for crop when the machine has to displace much crop. Finally the screen prevents the crop from reaching the rotor and thus from impeding a good operation of the implement. The lower side of the screen may be located at a height above the ground which is smaller than the height above the ground of the upper point of an upwardly pivoted arm. In this manner there is obtained sufficient freedom of movement on the ground and the arm is enabled to pivot freely. According to a further inventive feature, one or more pivotal axes of the arms are at a fixed distance from the axis of rotation and the pivotal axes are located in the direction of a tangent that touches almost tangentially the path described by the pivotal axes. In a preferred embodiment the arms describe a circular path, so that the pivotal axes are located on a circle. According to another inventive feature, the pivotal axes of one or more tines are at a fixed distance from the axis of rotation, and the pivotal axes of one or more tines are located in the direction of a tangent that touches almost tangentially the path described by the pivotal axes . In accordance with a further aspect of the invention, when the implement is operative, one or more tines enclose an angle of approximately 15° with the ground. One or more arms may be provided with one or more groups of tines . According to another inventive feature, one or more tines of an arm have such a centre of gravity that, when the implement is operative, the resultant of the gravitational and the centrifugal force moves one or more tines towards the ground. In this manner it is achieved that, at a fixed rotational speed, the position of the tines relative to the ground always remains equal. According to another inventive feature, in the working position, the centre of gravity of a group of tines is situated at a greater distance from the ground than the pivotal axis. The centre of gravity of the ensemble of the arm and one or more tines may also be situated at a greater distance above the ground than the pivotal axis of the arm. Also in that situation the resultant of the gravitational and the centrifugal force moves the arm and the tines towards the ground. According to again another inventive feature, one or more tines of the arms pivot about one or more upwardly orientated axes that are connected to the arms. In this manner it is achieved that the tines can also move in a plane extending substantially parallel to the ground. According to another aspect of the invention, one or more stops that are connected to one or more arms limit the pivoting movement of the arm about the pivotal axis. In accordance with another aspect of the invention, in the transport position, one or more arms rest in a locking device. This locking device may consist of a flexible element, such as a flexible plate provided with a recess in which the arm can be clamped. The flexible element may have a round shape. According to a further inventive feature, the flexible element is made of elastic material, such as plastic or rubber. Instead of a flexible element provided with a recess, the locking device may also consist of a plate having one or more recesses and a spring. According to a further inventive feature, for the purpose of being locked one or more arms may be provided with one or more limiting cams. According to again another aspect of the invention, seen in side view, one or more arms have at least substantially the shape of an inverted U. According to another inventive feature, seen in side view, one or more arms are substantially straight. In accordance with a final inventive feature, when the implement is operative, the points of the tines, seen from above, describe circumferential paths that overlap each other. The invention will be explained in further detail with reference to an exemplary embodiment. Figure 1 is a plan view of a machine according to the invention; Figure 2 is a side view according to the arrow II in Figure 1; Figure 3 is, at an enlarged scale, a side view according to the arrow III in Figure 1; Figure 4 is, at an enlarged scale, a side view according to the arrow III in Figure 1, in which the rake member has an alternative embodiment, and Figure 5 is, at en enlarged scale, a plan view of a detail of Figure 4. The implement according to this embodiment can function as a tedder and as an implement for raking swaths . The machine comprises two rake members 1 and 2, which are rotatable about an upwardly orientated axis 3, 4 respectively. For that purpose the rake members are disposed on a frame beam 5 which is mounted on a frame portion 6 which extends forwardly in the direction of travel A during normal operation. To the frame portion 6 there is fastened a trestle 7 by means of which the implement can be coupled in a manner known per se to the three-point lifting hitch of a tractor. The trestle 7 comprises for the purpose lower coupling points 8 and an upper coupling point 9. In a manner known per se the frame portion 6 is pivotable relative to the trestle about an upwardly orien- tated axis 10. It is also possible to cancel the pivotability of the frame portion 6 relative to the trestle 7 upon lifting of the machine, which is advantageous when transporting the machine. In the frame beam 5 there is disposed a non-shown power supply, known per se, for the rake members, which power supply can be connected to the power take-off shaft of a tractor by means of a coupling shaft 11 and a non-shown intermediate shaft. During operation the rake members 1 and 2 are driven in opposite directions of rotation B and C, in such a manner that they have a rearward movement in the middle of the machine. At the rear side of the frame beam 5 there is fastened a carrier frame 12 on which, by means of a frame beam 13 that is connected to the carrier frame 12 so as to be pivotable upwards about horizontal axes 14, two swathers 15 are mounted. These swathers are connected to the frame beam 13 so as to be pivotable about upwardly orientated axes 16 and can be adjusted into a number of positions. The implement is provided in a manner known per se with a protective bracket 17 which is disposed around the front side and the rear side of the machine. In a particular embodiment the rake members 1 and 2 are each provided with ten arms 18 which are connected about axes 19 to a frame 20 of the rake member. The axes 19 cross the axes of rotation 3 and 4 at least approximately at an angle of 90°, and an imaginary line through the axes 19 constitutes a tangent relative to an imaginary circle that can be drawn around the axes 3 and 4. As shown in Figure 3, the arms 18 comprise a stop 21 which can come into contact with a hoop-shaped frame beam 22 of the frame 20 of the rake member. The downward movement of an arm is limited hereby. In side view, as shown in Figure 3, the arms 18 have the shape of an inverted U. By means of a leg 23 the arm 18 is connected to the frame of the rake member via the pivotal axes 19. In this exemplary embodiment, there are fastened two rake tines 25 and 26 to the other leg 24 of the arm 18. However, it is also possible that there are fitted one or three tines to each arm. In Figure 3 the arm 18 and the rake tines 25 and 26 are represented in the working position in which they extend outwardly. In this position the centre of gravity X of the arm is preferably situated at a greater distance 27 from the ground than the distance 28 of the pivotal axis 19 above the ground. The rake tines 25 and 26 are disposed on a carrier 29 which is connected to the leg 24 of the arm 18 so as to be rotatable about a pivotal axis 30. The pivotal axis 30 crosses the axes of rotation 3 or 4 of the corresponding rake member and is orientated during operation at least substantially horizontally and is located at least approximately tangentially relative to a circle extending around the axis 3, 4 respectively, the axis preferably enclosing an angle from 10° to 20° with the tangent. In a preferred embodiment the tine encloses an angle of 15° with the ground. The rake tines 25 and 26 and the carrier 29 have a centre of gravity Y which is situated at such a distance 31 above the ground that, under normal operational conditions, upon rotation of the rake member the tines pivot downwards by centrifugal force about the pivotal axis 30. Preferably the distance 31 above the ground is greater than the distance 32 of the pivotal axis 30 above the ground. The centre of gravity Z of the ensemble of the arm 18, the tines 25 and 26 and the carrier 29 is situated at such a distance 33 above the ground that, under normal operational conditions, upon rotation of the rake member the arms (18) with the tines (25, 26) pivot downwards by the resultant of the gravitational and the centrifugal force. Preferably the distance 33 above the ground is greater than the distance 28 from the pivotal axis 19 to the ground. In a manner known per se the tines are connected to the carrier 29 so as to be adjustable about an upwardly orientated axis 34, so that the tines can be adjusted into different positions, e.g. a position for creating a swath, in which the tines are in the most trailing position (Figure 1, rake member 2), and a position for the tedder, in which they are at least in a less trailing position (Figure 1, rake member 1 ) . Seen from above, the arm 18 has a shape in which, viewed in the direction of rotation B, C, the legs 23 and 24 extend somewhat rearwards . The frame 20 of the rake member consists of a carrier frame 35 to which five downwardly extending frame beams 36 are fastened. The lower sides of the frame beams 36 are fastened to the circular frame beam 22, so that there is created a carrier frame for the arms 18 and the rake tines 25 and 26. In this embodiment a total of 10 arms are disposed at equal mutual distances from the frame beam 22. By means of a number of arms 37, a screen 38 made of flexible material, such as a fabric coated with synthetic material, is fitted to the carrier frame 35 and disposed around the rake member, which screen 38 serves as a guide member for the crop that is displaced by the tines . The lower side of the screen 38 is located at a height 39 above the ground, which height 39 is smaller than the distance from the upper point of an upwardly pivoted arm 18 to the ground. However, the distance 39 of the lower side of this screen above the ground is greater than the distance 40 of the upper side of the arms 18 above the ground in the region of the screen. The height 41 from the upper side of the screen to the frame beam 22 is greater than the distance from the pivotal axis 19 to the outermost lateral side of the leg 24. The distance 39 is greater than 30 cm and amounts preferably to approximately 40 cm. The arms 18 and the tines 25, 26 can be brought into a transport position which is shown in Figure 3. The construction of the screen enables the arms 18 to pivot together with the rake tines 25 and 26, that are pivotable about the pivotal axes 30, in such a manner that they can be brought into a transport position along the lower side of the screen. For that purpose the rake tines 25 and 26 rotate anti-clockwise until they are positioned beside the arms 18 and then the arms and the rake tines can be brought together into the transport position along the lower side of the screen 38 that can be folded upwardly. In their folded up position the arms 18 are located between the frame beams 36 of the rake member. In that situation the arms and tines can no longer simply pivot outwardly. This is only possible when the screen 38 is pulled up. Because of the position of the centres of gravity Y and Z, the arms 18 with the tines 25, 26 are pushed against the ground during operation by the resultant of the gravitational and the centrifugal force exerted thereon. In this situation it is important that not only the tines, but also the combination of arms and tines, are subjected to this resultant, so that the effect of the tines is also favourable in case of an uneven soil, even in case of great unevennesses therein. As shown in Figure 1, the circles described by the tine points overlap each other. To that end the tines of the rake members are arranged in a somewhat staggered position. In this embodiment each arm is provided with two tines. Of course, an alternative in which the arm is provided with only one tine or more than two tines will be possible as well. As usual, the rake members are supported by running wheels 42 disposed thereunder. Figure 4 shows an alternative embodiment of the arm 18. Figure 5 shows a detail of Figure 4 at an enlarged scale. The direction of rotation is indicated as B and corresponds to the direction of rotation of the rake member in Figure 1. In this situation the arm is straight in side view. Like in the situation of the U-shaped arm, the leg 23 extends somewhat rearwards, as shown in Figure 5. Because of the position of the pivotal axes 19, 30 and the centres of gravity X of the arm and Y of the tines and the combined centre of gravity Z of the arm and the tines, there is still a resultant of the gravitational and the centrifugal force by which the arm 18 and the tines 25, 26 move towards the ground. In a preferred embodiment the tines enclose an angle of 15° with the ground. The movement of the arm towards the ground is limited by stops 21. There is not provided a screen 38. Instead thereof, in the transport position, the arms 18 come into a locking device 43 in which they are locked by clamping. In this situation the tines pivot downwardly in an equal manner as in the embodiment of Figures 1 - 3. In this embodiment the locking device is constituted by a flexible round-shaped plate provided with a recess in which the round tube of the arm 18 is clamped. In a preferred embodiment this locking plate is made of synthetic material or rubber. As an alternative the locking device may be constituted by a plate provided with a recess and a spring, in which situation the recess of the plate is pulled by the spring over a limiting cam provided on the arm 18.

Claims: CLAIMS 1. An implement for displacing crop lying on the soil, said implement comprising at least one rake member which rotates about an upwardly orientated axis and which is provided with one or more outwardly extending arms (18) that are pivotable in upward direction about one or more pivotal axes (19), which arms are provided with one or more outwardly extending tines (25, 26) that are pivotable about one or more pivotal axes (30), while, in the transport position, one or more tines (25, 26) of one or more arms (18) are pivoted downwards, characterized in that, when the implement is operative, the resultant of the gravitational and the centrifugal force moves one or more arms (18) with one or more tines (25, 26) towards the ground. 2. An implement as claimed in claim 1, characterized in that the rake member is provided with a frame (20) to which one or more arms (18) are connected, which arms (18), in the transport position, are pivoted in upward direction about one or more pivotal axes (19). 3. An implement as claimed in any one of the preceding claims, characterized in that the rake member is provided with a screen (38) disposed around the rake member and located above one or more arms (18). 4. An implement as claimed in claim 3, characterized in that the lower side of the screen (38) is located at a height (39) above the ground, which height (39) is smaller than the height above the ground of the upper point of an upwardly pivoted arm (18). 5. An implement as claimed in any one of the preceding claims, characterized in that one or more pivotal axes (19) of the arms (18) are at a fixed distance from the axis of rotation (4) and are located in the direction of a tangent that touches almost tangentially the circumferential path of the pivotal axes (19). 6. An implement as claimed in any one of the preceding claims, characterized in that, when the implement is operative, the pivotal axes (30) of one or more tines (25, 26) are at a fixed distance from the axis of rotation (4) and are located in the direction of a tangent that touches almost tangentially the circumferential path of the pivotal axes (30). 7. An implement as claimed in any one of the preceding claims, characterized in that, when the implement is operative, one or more tines (25, 26) enclose an angle of approximately 15° with the ground. 8. An implement as claimed in any one of the preceding claims, characterized in that one or more arms (18) are provided with one or more groups of tines (25, 26). 9. An implement as claimed in any one of the preceding claims, characterized in that one or more tines (25, 26) of an arm (18) have such a centre of gravity (Y) that, when the implement is operative, the resultant of the gravitational and the centrifugal force moves one or more tines (25, 26) towards the ground about the pivotal axis (30). 10. An implement as claimed in any one of the preceding claims, characterized in that, in the working position, the centre of gravity (Y) of a group of tines (25, 26) is situated at a greater distance (28) from the ground than the pivotal axis (30). 11. An implement as claimed in any one of the preceding claims, characterized in that the centre of gravity (Z) of the ensemble of the arm (18) and one or more tines (25, 26) is situated at a greater distance (33) above the ground than the pivotal axis (19) of the arm (18). 12. An implement as claimed in any one of the preceding claims, characterized in that one or more tines (25, 26) of the arms (18) pivot about one or more upwardly orientated axes (34) that are connected to the arms (18). 13. An implement as claimed in any one of the preceding claims, characterized in that the pivoting movement of the arm (18) about the pivotal axis (19) is limited by one or more stops (21) that are connected to one or more arms (18). 14. An implement as claimed in any one of the preceding claims, characterized in that, in the transport position, one or more arms (18) rest in a locking device (43). 15. An implement as claimed in claim 14, characterized in that the locking device consists of a flexible element provided with a recess in which the arm (18) can be clamped. 16. An implement as claimed in claim 15, characterized in that the flexible element has a round shape. 17. An implement as claimed in any one of claims 14 - 16, characterized in that the flexible element is made of elastic material, such as plastic or rubber. 18. An implement as claimed in claim 14, characterized in that the locking device consists of a plate having one or more recesses and a spring. 19. An implement as claimed in any one of claims 14 - 18, characterized in that one or more arms (18) are provided with one or more limiting cams. 20. An implement as claimed in any one of the preceding claims, characterized in that one or more arms (18) are tubular. 21. An implement as claimed in any one of the preceding claims, characterized in that, seen in side view, one or more arms (18) have at least substantially the shape of an inverted U. 22. An implement as claimed in any one of the preceding claims, characterized in that, seen in side view, one or more arms (18) are at least substantially straight. 23. An implement as claimed in any one of the preceding claims, characterized in that, when the implement is operative, the points of the tines (25, 26), seen from above, describe circumferential paths that overlap each other.

Inventors: KOORN MAARTEN, VAN HEMERT NORBERT, KOORN, MAARTEN, VAN HEMERT, NORBERT
Applicants: HEMERT NORBERT VAN, KOORN MAARTEN, MAASLAND NV, KOORN, MAARTEN, MAASLAND N.V., VAN HEMERT, NORBERT
Application year: 1998
Main classification: A01D78
IPC codes: A01D78