Device for changing throughgoing openings in separation area of a concave of a harvester

A device for changing throughgoing openings through which grain passes in a separating area of a concave in an agricultural harvester in which the concave is composed of at least one frame, and a plurality of beater strips and wires which form therebetween the throughgoing openings the concave separating area, the device comprising an adjusting device composed of a plurality of individual tines which are in operative connection with one another through at least one tine strip, a switching shaft, and at least one cam arranged on the switching shaft and controlling the tine strip, wherein the adjusting device is being configured so as to change a size of the throughgoing openings so as to determine a comminution degree of a product mat between a threshing drum and the concave.

BACKGROUND OF THE INVENTION

The present invention relates to a method of and a device for changing throughgoing openings of a concave in an agricultural working machine, in particular a self-propelled combined harvester.

The individual throughgoing openings of the concave separating area are determined by the distance between the beater strips and wires of the concave. The size of the throughgoing openings is decisive for the efficiency of the threshing of different crop types. For different crop types, differently sized throughgoing openings are needed to guarantee an unobjectionable threshing of the grain. Corn grains for example require greater throughgoing openings than wheat grains.

When the throughgoing openings are too great, a higher portion of non-grain components is separated on the concave, which leads to greater contamination of the grains separated on the concave. To the contrary, the throughgoing openings which are too small lead for example to clogging of the throughgoing openings, and therefore of the concave, with greater grains. Thereby the danger of corn breakage increases, so that the not thrashed crop above the concave separating area is blocked by further subsequent crop and in addition reduces contacting by the threshing drum.

German patent document DE 3832996 discloses a device for adjusting the distance between two successive rods on a concave. The rods are components of the concave and determine the throughgoing size for the crop. By adjusting the distance between two successive rods, in the same concave, without reconstruction of the elements, each type of harvest can be sufficiently threshed and separated. This is achieved in that each second rod is supported turnably. Flap elements are stationarily mounted on the rotatable rods. By turning the rods, the flap elements are moved in the corresponding rotary direction and in the space located in front of the movable rods. The turning rod is moved by the movement to the non-turnable rod.

The disadvantage is here the position which the flap elements assume in the turned position. In the lowered condition the flap elements are arranged inclined under the throughgoing openings. In this way the passage of the crop is prevented. The threshing of the crop is limited, since the free space under the separating surface of the concave is partially filled by the flap elements, that finally limits the further feeding of the crop after the threshing. Since the crop can no longer pass without obstacle between the rods, this leads to clogging in connection with grain breakage.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide a method of and a device for changing throughgoing openings in an agricultural harvester, in particular a combined harvester, which is convertable in a structurally simple and cost-favorable manner and allows a fine threshing of different crops without any negative effects.

In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated in a method for changing throughgoing openings in a separation area of a concave in an agricultural harvester in which the concave is composed of at least one frame, a plurality of beater strips and wires together forming the concave separating area, the method comprising the steps of arranging at least one adjusting device under the concave separating area; and adjusting a width of the throughgoing openings by the at least one adjusting device.

The other feature of the present invention resides, briefly stated, in a device for changing throughgoing openings in a separating area of a concave in an agricultural harvester in which the concave is composed of at least one frame, and a plurality of beater strips and wires which together form the concave separating area, the device comprising an adjusting device composed of a plurality of individual tines which are in operative connection with one another through at least one tine strip; a switching shaft; and at least one cam arranged on said switching shaft and controlling said tine strip.

Since the width of the throughgoing openings is changeable by at least one adjusting device arranged under the concave separating area, no change is needed for the available concave. In addition with the change of the width of the throughgoing opening it is guaranteed that a separation in an inlet region of the concave is avoided, so that under the action of the centrifugal force on the threshed grain, an increase of the concentration of grains in a threshing gap in the region of the concave can be performed, before a grain-chaff mixture is separated on the concave. This is especially advantageous in that the part of the separated non-grain component can be reduced, so that overloading phenomena at the following working elements, in particular in the cleaning device, can be avoided in a simple manner.

The adjusting device is arranged in the concave, and in accordance with the present invention is located under the concave separating area. Thereby the concave during harvesting can be fully loaded, without negatively influencing the crop harvesting by the adjusting device. An adjustment of individual rods or beater strips relative to one another is no longer necessary.

By guiding the adjusting device from above between the wires of the concave, the threshing and working region above or on the concave separating area remains not contacted.

The lateral and/or outward displacement of the adjustment device enhance the threshing of the crop. The adjusting device in its initial condition can be arranged so that the grains falling on it can be transported further without being limited by the adjusting device. A crop clogging is thereby excluded. In addition, the adjusting tines are introduced in the space between two neighboring beater strips, without a distance change between the beater strips or wires, that provides a significant technical simplification.

In view of the simple construction of the total adjusting mechanism, the adjusting tines can be lowered when not in use, without negatively influencing the further harvesting process, whereby the grains are directly threshed without negatively influencing their further transportation. Since the lowering is performed at a certain increased concentration of the crop on the concave separating area, correspondingly clean crop is separated, since the non-grain components are transported further before this.

The adjusting device is composed of a plurality of adjusting tines, which are in operative communication via at least one tine strip, and the tine strips are controlled via at least on cam arranged on a switching shaft. Therefore, the adjusting of the width of the throughgoing openings is controlled synchronously, and the adjustment of the width of the throughgoing openings is performed also synchronously and simultaneously. This guarantees a uniform threshing.

This synchronous adjustment can be expanded in a structurally simple manner to a plurality of tine strips connected in series. For this purpose all tine strips are controlled by a single switching shaft.

A particularly uniform threshing is provided when the adjusting tines of the adjusting device are arranged in lower condition on the vertical plane under the wires and/or beater strips. Due to this arrangement, the threshed grains pass without obstacle through the concave and so that the adjusting tines do not limit the required space.

The vertically adjustable arrangement of the adjusting device between the beater strips acts so that the adjusting tines can be also vertically adjustable in the vertical position between the wires of the concave. It is possible to position the adjusting tines deeper than the wires. Thereby during the threshing process first and mainly the beater strips and the wires are loaded, and after the adjusting tines. The load distribution serves for clearing the adjusting device and in particular the adjusting tines. On the other hand, the adjusting tines can be arranged also on one plane with the wires. Thereby a uniform separating area is provided.

In a structurally simple manner the distance of the adjusting devices relative to one another and/or the distance of the individual tines relative to one another can be equal or different. Thereby the size of the throughgoing openings can be additionally varied.

With the exchangeability of the total adjusting device is guaranteed that the exchange or the removal of the adjusting device can be performed also during the use in a simple manner. This in particular has the advantage that it is possible to react to changing harvesting conditions fast and without expensive conversion works.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1is a view showing a threshing mechanism of a not shown combine harvester on a side view. The threshing mechanism includes a drivable threshing drum2and an associated concave3. The concave3is composed of a frame4and a plurality of webs5and beater strips6stationarily integrated in it.

FIG. 2shows a perspective view of an adjusting device10under the concave3. Several tine strips30are located one behind the other in a row.FIG. 2shows that in a structurally simple manner any number of the tine strips30can be arranged under the concave3. The adjusting device10can cover basically the whole region under the concave3. For providing a synchronous control the tine strips30when needed, they are controlled simultaneously and synchronously by a single switching shaft16. An adjustment is performed in accordance with the principle which is illustrated inFIGS. 4 and 5.

Wires7which are located parallel to one another extend through openings inside the beater strips6. Individual throughgoing openings8of a concave separating area9are formed by the distances between the wires7and the beater strips6with respect to one another. The size of the throughgoing openings8determines the comminution degree of the product mat between the threshing drum and a concave. For different crop types, differently dimensioned throughgoing openings8are required, to guarantee an efficient threshing and separation of the grains.

The inventive adjusting device10is arranged under the concave separating area9. The width of the throughgoing openings8is adjustable by the adjusting device10. The adjusting device10is composed of a plurality of adjusting tines15which are arranged behind and near one another, separated by neighboring beater strips6. They extend radially at an angle to the threshing drum rotary axis A shown inFIG. 1, in correspondence with the concave shape. The adjusting tines form a structural unit with a tine strip30. The switching shaft16serves for adjusting the adjusting tines15or the tine strips30and is connected at an outer side through a console17stationarily with the frame4. At the rear end of the switching shaft16it can be formed with a wrench width18for adjustment. Thereby the adjusting can be performed manually. In a further embodiment of the present invention, the adjustment can be performed by an electric motor19shown in a broken line inFIG. 1or an adjusting lever19a.

FIG. 3shows a section of a detail ofFIG. 1identified with a dash-dot line. It illustrates the arrangement of the adjusting device10and the adjusting tines15relative to the beater strip6and the concave wires7.

In the initial position or rest position, the adjusting tines15as shown inFIG. 1, are located under the wires7and in the same vertical plane. The tine strip30is movably connected by a pin20with a console17which is additionally welded on the beater strip6. A rotatable control plate22is integrated between a screw head21and a console17. The pin20which passes through the free end of the console17is associated with the adjusting device10which obtains a predetermined arrangement relative to the beater strip6by a cover disk23which is fixed with a nut24. The control plate22is connected with a further pin25. This connection corresponds to the previously described connection of the pin20and therefore is not explained in detail.

The nature of the cooperation of the arrangement of the pins20,25, the control plate22, and the adjusting device10can be seen fromFIGS. 4 and 5.

FIG. 4shows the adjusting device10in a lowered condition. The adjusting tines15are located directly under the wires7of the concave3. The tine strips30follow, as the beater strips6, the geometry of the concave3. In the region of the webs5, the tine strips30are provided with recesses31that allow a lateral displacement of the tine strips30of the adjusting device10. In the region between the adjusting tines15, the tine strips30have depressions32that allow a movement of the adjusting tines15in the intermediate spaces between the wires7, without limiting the adjustment ability of the tine strips30by the available wires7of the concave3.

A console17is shown in dash-dot line behind the tine strip30inFIGS. 4 and 5. This console17is fixedly connected with the beater strip. The console17is in turn in operative connection with a control plate22arranged stationarily but rotatably on the tine strip30. The control plate22is also shown in a dash-dot line and is connected in its end regions by the corresponding screw pins20,25rotatably with the console17and the tine strip30. During displacement of the adjusting device10along the tine strip30, the pin20leads the tine strip30along an elongated hole33provided in the tine strip30. Due the connection between the control plate22, the tine strip30and the console17, as well as the shape of the elongated hole33, the adjusting tines15are turned to the corresponding position. The shape of the elongated hole33determines a curved path36(FIG. 4), over which the adjusting tines15move from their lowered position37to their raised position38for at least partially closing the throughgoing openings8.

In the lowered position of the adjusting device10, the adjusting tines15are arranged directly under the wires7of the concave3. This position is adjusted by turning of the cam34. The cam34moves inside a switching coulisse35and is located in a disengaged position37of the adjusting tine15flush at the right side of the switching coulisse35. The switching coulisse35is preferably U-shaped. For performing the adjustment of the device10, the cam34that is stationarily integrated on the switching shaft16, can be controlled manually, mechanically or hydraulically and turned in an arrow directions39.

The lowering of the adjusting device10is performed in accordance with the present invention when high quantity of grains are concentrated on the concave separating area9. By the correspondingly performed lowering of the adjusting device10the collected grains with a small part of non-grain components move over the wires7into a not shown working unit, for example a cleaning device.

As can be seen fromFIG. 5, the adjusting device10after complete adjustment of the cam34is located in a raised position, and the adjusting tines15are located in their set up position38. The cam34abuts then flush at the left side of the switching coulisse35. Thereby the tine strips30are displaced to the left by the length of the cam34. For positioning of the adjusting tines15of the tine strips30accurately between the wires7of the concave3, the tine strips30as described herein above, are connected with a console17which is arranged stationary on the beater strip6.

By controlling the cam34the tine strip30is displaced inclinedly upwardly. This displacement is obtained by displacing the control plate22to the left by an identical amount as the tine strip30. Thereby the pin20of the tine strip30, which is in operative connection with the control plate22and the console17, is guided along the elongated hole33. In this manner the adjusting device10obtains the accurate adjustment.

The present invention, and in particular its method and a device for performing the method, are not limited only to the concave3of an agricultural harvester, but instead can be used in any working machine for obtaining the same effect.

While the invention has been illustrated and described as embodied in method of and device for changing throughgoing openings in separation area of a concave of a harvester, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.