GB1559424A - Seed drill - Google Patents

Description

(54) SEED DRILL (71) We, AMAZONEN-WERKE H. DREYER of Am Amazonenwerk, 4507 Has bergen-Gaste, Federal Republic of Germany; a German company do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a seed drill capable of being hitched to a tractor and has a storage container and outlet openings from which material contained in the storage container is supplied to the soil via a metering device and conduits connected thereto.

Materials are supplied to the conduits and drop therefrom into the tracks formed by the tractor wheels and are controlled by means of a control device so as to be switched-off and switched-on in periodical repetition, whereby for this control a unilaterally acting overrunning clutch device is provided adapted to be driven by the movement of a tractor part during a turn at the end of the field. The overrunning clutch device during each turning movement is turned through an equal part of a circle and is positively connected with a guide element by means of which the elements for switching-off and switching-on again of the material feed are actuated. The purpose of such drilling devices is to permit the execution of so-called"tramlines"whereby with seeding in periodical repetition the tractor tracks are kept clear of seed material, so that these tracks may be repeatedly used by implements for subsequent top dressing treatments without damage to the growing plants/seedlings.

A seed drill is disclosed in German Offenlegungschrift 21 61 643 wherein an overrunning clutch device comprises a stepping mechanism having a thrust wheel which is provided at its periphery with three teeth and a guide element protrudes laterally beyond the region of a tooth and against which element the switch lever of a change-over switch of the device is retained in abutment for switching material supply off and on. This switching off and on of the material supply for the particles of material dropping into the track of the machine towed by the tractor is effected by disengaging the corresponding cam wheels of the metering device from their driving device and connecting such thereto again. The switching device is fitted with an electric motor which on the one hand is connected via a linkage and coupling elements to the corresponding cam wheels of the metering device and on the other hand is electrically connected to the change-over switch. Within the circuit controlled by the change over switch an indicating device is provided in the form of an electric light bulb located within the field of view of the tractor driver and which bulb is constantly lighted during the interruption of the material supply. The thrust wheel of the clutch device is mechanically actuated during the turn by the steering spindle pushrod of the tractor towing the machine or by a guide rod of the power lift of the tractor. Moreover, the whole apparatus may be switched off manually.

This seed drill has the disadvantage of being a relatively costly and breakdown-prone construction of the whole switching device. Above all, however, it is disadvantageous in that following implements such as, for example, fertilizer spreaders and field sprays used during the lane method may only have a working width which is either divided accurately by the numeral three or a multiple of this number corresponding to the working width of the seed drill. It is necessary to note that with perfectly equal working widths the whole switching device has to be switched off in a state in which the cam wheels for discharging the material particles in the tractor tracks are disengaged from their drive. If the seed drill, for example, has a working width of 4 metres, then the implements following on can be used only if their working width is 4.12 metres or 24 metres. For agricultural purposes this implies that when obtaining a seed drill suitable for use in connection with the lane method, existing trailing machines which do not fit in the aforesaid system of working widths have to be replaced at the same time. There is one disadvantage with regard to the indicating device and this is that in the unlit state of the bulb the tractor driver only knows that the material supply is open. He is, however, unable to see how many turns have still to be carried out before that the material supply is again cut. More especially, when the thrust wheel of the overrunning clutch device is actuated by a guide rod of the tractor power lift, and the seed drill, for example, for removing the toppings and root parts possibly adhering to the shares during straight travel, there occurs the forcibly actuation of the thrust wheel which then leads to the interference with the periodic return for the switching off operation without the tractor driver being particularly referred thereto.

German Offenlegungsschrift 15 57 906 discloses a seed drill suitable for use in the lane method, in which all the outlet openings are closable by sliders and the sliders of the outlet openings, from which the material is fed to the tractor tracks, are connected to a manually actuatable device for switching the material supply off and on. This seed drill has the advantage that the implements following-up may have the working width of the seed drill or a multiple of this working width. Similarly, with a working of the seed drill width of 4 metres the follow-up implements may have a working width of 4,8,12,16,20,24.... m.

Furthermore, the apparatus for switching the material supply off and on again is of simple construction.

It is, however, a disadvantage of this seed drill in that the tractor driver during the whole use of the machine must not forget the manual control of the apparatus and accurately note the stage at which the material supply for the tractor tracks has to be switched off in accordance with the working width of the follow-up implements. Excessive demands are thus placed on the tractor driver who should be essentially concentrating on driving accurately in line so that many errors in shutting off the material supply result in practice which cannot be subsequently remedied without damage to the growing plants.

It is an object of the invention to develop a machine to provide automatic actuation of an overrunning clutch device during the turning operation or the raising of the seed drill necessary therefor to cut off the material supply to the tracks of the tractor wheels so that, with simple means, adaptation of its periodical return to a large number of working widths possible for the following up implements is attained.

According to the present invention there is provided a seed drill capable of being coupled to a tractor, comprising a storage container and outlet openings from which the material when contained in the storage container is supplied to the ground via metering devices and conduits connected thereto wherein from some of which conduits in use the material drops into the tracks formed by the-ractor wheels and wherein the material supply for said some conduits may be switched on and off again by means of a switching device in periodic repetition; a drivable overrunning clutch device provided for the switching device and cooperable with a tractor part so as to be displacable during a turn at the end of the field, said overrunning clutch device during each turn being rotated through an equal portion of a circle and being positively connected with a guide element which actuates elements for said switching off and switching on of the material suppty ; and an indicating device for indicating the condition of said supply, characterised by the feature that there is a positive connection between the overrunning clutch device and the guide element and said guide element is provided so as to be disengageable or detachable.

It is thus consequentially possible with the drill of the invention in a simple manner to exchange an existing guide element for a different one, so that, as in the seed drill with material supply adapted to be manually shut off, the subsequent working implements may have a working width which is equal to the working width of the seed drill or is a multiple of this working width.

An embodiment of the invention provides for the freewheel device, the guide element and the indicating device to be arranged on one shaft, whereby the indicating device has the shape of a body provided with varying symbols and the number of symbols corresponds to the number of turning operations of the seed drill which are conditioned bv the shape of the guide element are necessary from inclusive one to the next shutting off of the material supply. The tractor driver can consequently ascertain at any time how many turning operations have to be carried out with the seed drill until the material supply to the tracks of the tractor wheels is again in a shut off state, for one working lane. This monitoring possibility has a particular significance when the seed drill is adapted purely as an attachment machine and the clutch device for the switching off and on again of the material supply to the tracks of the tractor wheels is actuated by one of the guide arms of the tractor power lift during lifting of the seed drill. If such a case the seed drill has, for any reason, to be lifted during straight travel i. e. from a working track, then the indicating device, noticeable to the tractor driver, progressively switches by a stroke. This provides the possibility for him by a single or repeated subsequent lifting and lowering of the machine to cause the switching device to again assume the correct stroke for switching off the material supply.

Because the guide element and the indicating device are connected to form a unit, the means for the above-described adaptability are still further substantially simplified. The embodiment of the invention herewith also provides for the freewheel device, during each movement in the same direction of the tractor part positively connected thereto, to be progressively rotated through an angle of 6 . With the corresponding exchange of the guide elements and the indicating device with the automatically acting switching device, the same number of working widths for the following working implements may thereby be automatically attained as in the known manually actuated apparatus.

A particularly operationally reliable embodiment resides in that the clutch device is formed in known manner as a stepping mechanism and that its pawl wheel is fitted with twelve equidistantly arranged teeth, whereby, with each movement, the thrust wheel is progressively rotated with the tractor part positively connected thereto by one tooth. A slight disadvantage results in that the trailing implements with a fivefold working width of the drill cannot be used, but this is compensated again by the simplicity of the design and for practical purposes, is of subordinate importance.

In a preferred embodiment of the invention, moreover, the sliders are provided in front of the outlet openings, and the switching off and switching on again of the material supply is effected by closing and re-opening the outlet openings by means of these sliders. The guide element comprises a cam disc having the cams equidistantly located on the outer circumference and wherein the switching device is provided with a sensor element which on the one hand is retained in abutment on the guide element and on the other hand is connected to the sliders of the outlet openings from which the material is conducted towards the tracks formed by the tractor wheels. This embodiment is also distinguished by considerable simplicity and operational reliability.

In the event of sliders adjacent to one another having to be moved simultaneously, for each tractor wheel track owing to its width there requires to be provided for actuation of these sliders a hydraulic cylinder connected to a control valve, whereby this control valve is connected via a hydraulic conduit to the pressure end of the hydraulic cylinder provided on the tractor towing the machine and for actuating its power lift. Further the control element of the control valve is positively connected to the sensor element. A simplification is thus attained in that the sensor element is located on the control member of the control valve.

Finally, an embodiment of the invention provides for the overrunning clutch device, the guide element, the sensor element to be located, in a closed housing. This measure provides a particularly suitable arrangement for rough agricultural operations since the most essential functional components in contact with each other are protected against external influences.

The invention will be described further by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic fragmentary plan view of a field tilled by way of the lane method with a machine in accordance with the ; Figure 2 is a longitudinal section along the working direction of a seed drill as an attachment machine; Figure 3 is an enlarged longitudinal section, an upper part of the machine of Figure 2 showing a metering device: Figure 4 is a longitudinal section through a central part of a switching device; and Figure 5 is a section on the line A-B of Figure 4 through the central part of the switching device.

A seed drill 4 is shown coupled to the power take-off 2 of a tractor 3 and is driven to and fro over field 1 so that the working tracks 5 and 5'of the seed drill 4 are accurately adjacently interrelated. The furrows 6 supplied with seed are illustrated by broken lines. As is shown the material supply for the region of the tracks 7 of the tractor wheels 8,8'is shut off in each third working track 5 so that these tracks remain open or unseeded and are to be used for the traversa of a trailing working implement. Switching off and on of the material supply is effected in a manner to be described subsequently by the actuation of the power take-off 2 during the turning operation effected at the end of the field and indicated by arrows 9. In this embodiment the trailing working implements will have treble the working width of the seed drill 4.

The essential parts of the seed drill 4 are shown in Figure 2 wherein the drill is attached to the power take-off 2 of the tractor 3 and has a frame 10 which in the lowered working position is supported on the ground via two running wheels 11 and which has a material storage container 12 mouned thereon. The material contained in the storage container is conveyed by means of a screw conveyor 13 into an upper container 14 and via'outlet openings 16 closable by means of sliders 15 arrives at a metering device 17. This metering device 17 comprises cam or seed metering wheels 18 driven in known manner (by means not shown) with regulatable speed, and an adjustable base flap 19 to enable material to be supplied to the ground in accurately regulatable quantities via the seed conducting tubes 20 and the share 21. Sliders 15 are operable to close the outlet openings 16 from which material is supplied to the tracks 7 of the tractor wheels 8,8' and are positively connected to the switching device 22. The switching device 22 comprises an upper part 23 located on the container 14 and a central part 24 located at the front of the storage container 12.

The upper part 23, shown in Figure 3 on an enlarged scale, inclues the elements used for switching off and again switching on the material supply for the tractor tracks 7. These elements comprise two struts 25 which on the one hand are connected to the sliders 15 for actuating the switching device 22, and on the other hand each connected to a lever 26 secured to a shaft 27 rotatably mounted on the container 14. A lifting arm 28 is non-rotatably mounted on the shaft 27 and has connected thereto the connecting rod 29 of a unilaterally acting hydraulic cylinder 30 and a tension or return spring 31 also connected to the hydraulic cylmder 30. A flexible hydraulic hose or pipe 32 leads into the lower part of the hydraulic cylinder 30. hydraulic cylinder 30.

This hydraulic pipe 32 as shown in Figures 4 and 5 is connected to a control valve 33 located in the central part 24 of the switching device 22. On the side of the control valve 33 opposite the connecting point of pipe 32, a further flexible hydraulic hose or pipe 34 is connected and leads to the pressure side of a hydraulic cylinder 35 located on the tractor3 and effecting the actuation of the power lift 2. The piston 36 of the control valve 33 has a bore 37 formed therein which in the position shown in Figure 4 interconnects the two hydraulic pipes 32 and 34 so that the hydraulic fluid can pass from one pipe to the other*.

A roller 38 is rotatably mounted on the lower end of the piston 36 as a sensor element and by means of the spring 39 roller 38 is retained in abutment with a guide element 40 comprised of a cam disc. Cams 41 are equidistantly located on the guide element 40 and have a height which is greater than the diameter of the bore 37. The guide element 40 is rotatably mounted on a shaft 43 by means of the bush 42 and said shaft is fixedly mounted in the housing 44 and on the side of the guide elements 40 which together with the bush 42 protrude from the housing 44. A ratchet wheel 45 of an overrunning clutch device 46 is also rotatably mounted on this shaft and adapted as a stepping mechanism and has twelve equidistantly spaced teeth 47 over its circumference. The ratchet wheel 45 and the guide element 40 are positively interconnected by a simple socket coupling 48. For the axial securing of the guide element 40 and the ratchet wheel 45 a bearing disc 50 is secured on the head end of the shaft 43 and externally of the housing by means of a wing screw 49 and bush 42 loosely abuts thereagainst.

Furthermore, a switching lever 51 is pivotally mounted at one end in the housing 44 and is so connected at its front end by a cable 52 to a gear housing 53 of the tractor 3 that the switching member 54 pivotally mounted on the lever 51 within the housing 44 abuts against a tooth 47 of the ratchet wheel 45. The operating lever 51 is also connected to the housing 44 by a tension spring 55 which exerts a force on the operating lever 51 in direction opposite to that of the ratchet wheel 45. Firmly connected outside the housing 44 is indicating device 56 adapted as a cup-shaped disc and on the peripheral surface of which in accordance with four times the number of teeth 47 on the ratchet wheel 45 the symbols 57 comprised of two and three lines are located equidistantly relative to each other. A marker device 58 is also mounted on the housing 44 outside the indicating device 56 and points with its tip to a symbol 57.

The switching device 22 operates as follows: Commencing with the outlet openings 16 which enable the material to be supplied into the tracks 7 of the tractor wheels 8,8'being closed by the sliders 15 and as is the case in the given third working tracks or lanes 5 corresponding to Figure 1. As shown in Figure 2, the seed drill 4 is in the lowered, working position, so that the pressure end of the hvdraulic cylinder 35 located on the tractor 35 is without pressure. Furthermore, in accordance with Figure 4, the roller 38 located on the piston 36 is on a cam 41 of the guide element 40 so that the bore 37 assumes such a position that the hydraulic fluid flows back through the hydraulic pipes 32 and 34 into the hydraulic system of the tractor 3 so that the hydraulic cylinder 30 is in a condition without hydraulic pressure. Accordingly, the spring 31, via a lifting arm 28, the shaft 27, the levers 26 and the struts 25, has slid the sliders 15 into the closed position and retains them in this position.

For lifting the seed drill 4 prior to turning at the end of the field, hydraulic fluid is pumped into the pressure end of the hydraulic cylinder 35 in known manner (not shown) so that the hydraulic fluid flows via the hydraulic pipe 34, the bore 37 and the hydraulic pipe 32 into the hydraulic cylinder 30 urges the hydraulic piston with the connecting rod 29 upwards, so that the sliders 15 via the lifting arm 28, the shaft 27, the two levers 26 and the struts 25 are drawn upwards and hence expose or open the outlet openings 16.

At the same time, the piston 59 of the hydraulic cylinder is forced backwards so that the power lift 2 pivots upwards by means of the lifting mechanism 60 connected to the piston 59 and the seed drill 4 is thus lifted into the transportation position. The operating lever 51 via the cable 52 is thereby pivoted downwards so that the operating member 54 rotates the ratchet wheel 45 through the spacing distance between two teeth 47, i. e. through 30 . The guide element 40 is now also rotated through the same angle whereby the roller 38 rolls off the cam 41 located at the top and the piston 36 of the control valve 33 is pushed downwards by the spring 39. The bore 37 is consequently also moved downwards, so that the hydraulic pipe 32 is isolated from the fluid supply through hydraulic pipe 34.

Following the lowering of the seed drill 4 after the turn, the hydraulic fluid is now prevented from flowing back from the hydraulic pipe into the hydraulic system of the tractor 3 and the sliders 15 remain open during the next working track 5'. The operating lever 51 is again pivoted upwards by the force of the tension spring 55 so that the switching or operating member 54 abuts against the next tooth 47 of the ratchet wheel 45. To prevent the ratchet wheel 45 from turning in a reverse direction, a resilient locking member 61 is located on the housing 44 on the opposite side of the ratchet wheel 45 and with its upper part also abuts against a tooth 47.

Renewed lifting of the seed drill 4 at the next and opposite end of the field again causes the ratchet wheel 45 and the guide element 40 to turn on the shaft 43 through 30 . The roller 38 and hence the piston 36 of the control valve 33 thus remain in the lower position, so that when lowering the seed drill 4 after executing a turn, the hydraulic fluid is prevented from flowing from the hydraulic cylinder 30 via the hydraulic pipe 32 and for the subsequent working track 5'the sliders also remain in the upper position. Accordingly, material can be supplied through the outlet openings 16 in the predetermined adjusted quantity and to the tracks 7 produced by the tractor wheels 8,8'.

Upon the next lifting of the seed drill 4 at the opposite end of the field, the ratchet wheel 45 and hence the guide element 40 is again caused to be turned through 30 . Herewith, however, the roller 38 and hence the piston 36 is lifted by the next cam 41 into the position shown in Figure 4, so that the path for the hydraulic fluid through the bore 37 of the hydraulic pipe 34 to the hydraulic hose 32 and vice versa is exposed. During the lowering of the seed drill 4 after the turn, the hydraulic fluid can flow back from the cylinder 30 in the hydraulic system of the tractor 3 so that the sliders 15 are pushed into the lower closed position by the spring 31 and no material drops into the tracks 7 of the tractor wheels 8,8' during the next working track 5.

In this timed sequence, the switching operation is repeated during the whole field work, whereby the tractor driver can seen on the indicating device 56 in which timed sequence for opening and closing the outlet openings 16 the switching device 22 is situated. The positions marked by a dash show the closed positions and the positions marked by two or three dashes of the indicating device 56, represent the open position of the outlet openings 16.

If a different time sequence is to be obtained for trailing machines having other than treble the working width of the drill, then after unscrewing the wing nut 49 only the indicating device 56 with the bush 42 and the guide element 40 need be removed from the shaft 43 and replaced by correspondingly differently divided elements. For this purpose a circular opening 62 is formed in the side wall of the housing 44 and has a diameter of which is somewhat larger than the maximum diameter of the guide element 40. In this manner the following working width ratios relative to the working width of the seed drill may be obtained: Number of cams Number of different Ratio of the 41 equidistantly symbols 57 on the working width of spaced relative to indicating device 56 trailing machines each other on the relative to the guide element working width of the seed drill 4 2 2 x 6 symbol 6 : 1 3 3 x 4 symbol 4 : 1 4 4 x 3 symbol 3 : 1 6 6 x 2 symbol 1 : 1 12 or 13 x 1 symbol 1 : 1 continuous ring with or without the outer diameter of symbol. the cam If in addition five fold working width is also to be attained for the trailing machines, then a ratchet wheel with 60 teeth has to be used whereby such cam wheel may be progressively rotated only through 6 during lifting of the machine.

Claims (10)

WHAT WE CLAIM IS:

1. A seed drill capable of being coupled to a tractor, comprising a storage container and outlet openings from which the material when contained in the storage container is supplied to the ground via metering devices and conduits connected thereto wherein from some of which conduits in use the material drops into the tracks formed by the tractor wheels and wherein the material supply for said some conduits may be-switched on and off again by means of a switching device in periodic repetition; a drivable overrrunning clutch device provided for the switching device and cooperable with a tractor part so as to be displaceable during a turn at the end of the field, said overrunning clutch device during each turn being rotated through an equal portion of a circle and being positively connected with a guide element which actuates elements for said switching off and switching on of the material supply ; and an indicating device for indicating the condition of said supply, characterised by the feature that there is a positive connection between the overrunning clutch device and the guide element and said guide element is provided so as to be disengageable or detachable.

2. A seed drill as claimed in claim 1, in which the clutch device, the guide element and the indicating device are located on a shaft; said indicating device having the shape of a body provided with different symbols with the number of different symbols corresponding to the number of turning operations with the seed drill which is determined by the shape of the guide elements required from inclusive one to the next cut-off of the material supply.

3. A seed drill as claimed in claims 1 and 2, in which the guide element and the indicating device are interconnected to form a unit.

4. A seed drill as claimed in any of claims 1 to 3, in which the clutch device is turned progressively through an angle of 6 with each movement in the same direction of the tractor part positively connected therewith.

5. A seed drill as claimed in any of claims 1 to 3, in which the clutch device is formed as a stepping mechanism, and in which the ratchet wheel thereof is provided with twelve equidistantly spaced teeth whereby the ratchet wheel positively coupled thereto is progressively rotated by one tooth in the same direction with each movement of the tractor part.

6. A seed drill as claimed in any of the preceding claims, in which sliders are located in front of the outlet openings whereby the switching off and ori of the material supply is effected by closing and re-opening the outlet openings by means of these sliders, in which the guide element comprises a cam disc having cams provided on the outer circumference thereof and equidistantly spaced, and in which the switching device is provided with a sensor device which on the one hand is retained in abutment against the guide element and, on the other hand, connected to the sliders of the outlet openings, from which the material is conducted to the tracks formed by the tractor wheels.

7. A seed drill as claimed in claim 6, in which a hydraulic cylinder connected to a control valve is provided for actuating the sliders whereby this control valve is connected via a hydraulic conduit to a hydraulic cylinder provided on the pressure end of the tractor towing the machine for actuating the power lift, and in which the control element of the control valve is positively coupled to the sensor element.

8. A seed drill as claimed in claims 6 and 7, in which the sensor element is located on the control member of the control valve.

9. A seed drill as claimed in claims 6 to 8, in which the clutch device, the guide element, the sensor element and the control valve are located in a closed housing.

10. A seed drill constructed and arranged to operate, substantially as herein described with reference to and as illustrated in the accompanying drawings.