Mowing machine

A mowing machine comprising at least three mower members which are arranged rotatably about substantially vertical axes on a supporting beam containing drive means. The drive means includes a rotating torsion shaft which is driven at both ends thereof and carries gears for driving the mower members.

BACKGROUND OF THE INVENTION 
The invention relates to a mowing machine comprising at least three mower 
members which are arranged rotatably about substantially vertical axes on 
a supporting beam having accommodated therein drive means for driving the 
mower members. The supporting beam, during operation, extends 
substantially transversely to the direction of operative travel. The drive 
means are driven, near the two ends of the supporting beam, by means of 
mechanically intercoupled drive shafts. 
A mowing machine of this type is disclosed in the Netherlands Patent 
Specification No. 171,955, which describes a disc mower comprising mowing 
discs provided above a supporting beam, the two outermost mowing discs 
including a drum-shaped crop guide. Above, and parallel to the supporting 
beam, there is disposed a main drive shaft which is connected via gear 
wheels to two secondary drive shafts. Each secondary drive shaft is 
accommodated in one of the drum-shaped crop guides and is connected to an 
outermost mowing disc. Thus, the two outermost mowing discs on the 
supporting beam are driven. A series of meshing gear wheels is arranged in 
the supporting beam in such a manner that each one of the other mowing 
discs is driven from one of the secondary drive shafts. Preferably, the 
mowing disc which relative to the hauling vehicle, is the outermost disc, 
is driven via on of the secondary drive shafts and the remaining mowing 
discs are driven via the other such drive shaft. The reason for this is 
that the mowing disc most remote from the hauling vehicle is loaded to the 
highest extent due to the presence of the crop guide in the thick of the 
crop. 
SUMMARY OF THE INVENTION 
The object of the invention is to provide a mowing machine wherein the 
power supplied to the mower members is distributed optimally over the two 
secondary drive shafts. To this end, the drive means include a torsion 
shaft which is capable of rotating, extends through the supporting beam 
and carries gear wheels for driving the mower members. The use of a 
torsion shaft, extending in the longitudinal direction of the supporting 
beam provides for all mower members being flexibly interconnected. A 
section of the torsion shaft, functioning as a torsion spring, is provided 
between each pair of interconnected, adjacent mower members. This flexible 
interconnection renders it possible for all the mower members to be 
intercoupled, while permitting the drive means at the two ends of the 
supporting beam to be driven by means of secondary drive shafts which are 
intercoupled mechanically, i.e. non-flexibly. Since the entire row of 
mower members is flexibly intercoupled, the extent to which each mower 
member is driven from either the one or the other secondary drive shaft 
will depend upon the load carried by the furthest removed mower members. 
Thus, an optimum force distribution is obtained automatically. 
It will be obvious that, when gear wheels are used for intercoupling the 
mower members, as described in Netherlands Patent Specification No. 
171,955, a non-flexible connection between the mower members is obtained, 
which precludes driving a mower member via both secondary drive shafts. 
According to a further feature of the invention, the torsion shaft may have 
an out-of-round cross-section and the gear wheels which are fitted 
slidably on the torsion shaft are provided with an appropriately shaped 
center hole. This renders it possible to slide the torsion shaft axially 
the gear wheels and relative to the supporting beam and, thereby remove 
the shaft from the supporting beam. For example, the torsion shaft may be 
of a square cross-section with a thickness that permits sufficient power 
to be transferred, while providing sufficient flexibility. 
In accordance with a further feature of the invention, the supporting beam 
may be located just above the soil during operation and the mower members 
may be provided with discs arranged above the supporting beam. For 
example, the discs may be of a circular or oval shape and may have a 
somewhat upwardly directed convex form. One or a plurality of cutters may 
be mounted on the periphery of the discs. In addition, according to the 
invention, the drive of the torsion shaft may be effected via the two 
outermost mower members arranged on the supporting beam. The power 
supplied is then passed to the torsion shaft via each of the two mower 
members and the gear wheels, by means of which the mower members are 
connected to the torsion shaft, so that the torsion shaft need not be 
engaged separately in order to be driven. 
In accordance with a further feature of the invention, the outermost mower 
members may be provided with upwardly extending drums accommodating the 
secondary drive shafts for driving the torsion shaft. In this connection, 
a "drum" should be understood to mean a crop guide which may have a 
variety of shapes and, in particular, may be provided with means arranged 
on its circumferential surface area for exerting a force on the crop 
during rotation. The drums may be of a substantially cylindrical shape, 
although other shapes are possible as well. Consequently, the word "drum" 
should be interpreted broadly. 
In addition, in accordance with the invention, the supporting beam may be 
connected to the rest of the frame of the mowing machine by means of the 
two secondary drive shafts, which also secondary drive the torsion shaft. 
Due to the presence of two drive shafts, it is possible, at least when the 
shafts are adequately supported by bearings to connect the supporting beam 
to the rest of the mowing machine frame without the use of additional 
attachment means. 
In accordance with a further feature of the invention, the drive may be 
effected via a main drive shaft which extends substantially parallel to 
the supporting beam and drives the two secondary drive shafts positioned 
substantially perpendicularly to the main drive shaft, each of which 
secondary drive shafts drives the torsion shaft near an end of the 
supporting beam. 
In accordance with a further feature of the invention, the secondary drive 
shafts may include a flexible coupling, such as a universal joint and/or a 
joint provided with flexible material and/or a joint having portions which 
are axially slidable relative to each other. Such a flexible connection 
may be of importance in order to give the supporting beam as it moves over 
the soil, some freedom of movement during operation or to permit a less 
accurate positioning of the supporting beam with respect to the rest of 
the frame. 
According to the invention, the main drive shaft may be driven via gear 
wheels located between the connections to the secondary drive shafts, 
wherein the main drive shaft may consist of two sections which are 
substantially in alignment and are located on both sides of the location 
where the main drive shaft is engaged via gear wheels. It is alternatively 
possible to drive the main drive shaft from a position near its end. 
In accordance with a further feature of the invention, the machine may be 
provided, in addition to a mowing implement, with a crop processing 
implement, e.g. a conditioner. Such an implement can exercise a beating 
action on the crop, thereby crushing same, which facilitates drying. 
In accordance with a further feature, drum-shaped crop guides may be 
mounted on the outermost mower members and, taken in the lateral direction 
of the machine, the crop processing implement may be shorter than the 
length of the supporting beam. By means of the crop guides, the crop is 
directed slightly inwardly, as a result of which the crop processing 
implement may be of a somewhat shorter length than that of the supporting 
beam. By means of further crop guiding members, such as swath boards, the 
mown and optionally processed crop can ultimately be deposited on the soil 
in a narrow strip (swath). 
In addition, in accordance with the invention, a frame portion may be 
provided with wheels, in which frame portion the supporting beam is 
suspended capable of movement, the mowing machine including means for 
hitching same to a tractor. In such a special support for the mowing 
machine, a mowing implement of a considerable length is usually employed, 
in which connection a supporting beam that is driven from two ends can be 
particularly useful. 
In accordance with a further feature of the invention, the supporting beam 
is assembled from sections which are arranged against each other in the 
longitudinal direction of the supporting beam, a number of such sections 
being drive units for the mower members. A particularly advantageous 
construction of a mowing implement assembled from such units is obtained 
when, in accordance with a further feature of the invention, the sections 
are kept together by means of a tensile rod extending through all of said 
sections. 
For relatively large mowing machines, to which the present invention 
relates in particular, it is of the utmost importance that such an 
implement be down for repairs for as little time as possible during its 
period of operation. Due to the construction comprising modules which can 
be replaced as units, it is possible to carry out a repair rapidly by 
replacement. For this purpose, in accordance with a feature of the 
invention, the tensile rod and the torsion shaft, both parallel to and 
extending through the sections of the supporting beam, are removable, so 
that the seconds of the supporting beam are detachable and replaceable 
individually. 
For a better understanding of the invention and to show how the same may be 
carried into effect, reference will now be made, by way of example, to the 
accompanying drawings illustrating some embodiments of a mowing machine 
according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In the drawings, which give only a schematic rendering of the embodiments, 
corresponding component parts have been given the same reference numerals. 
The mowing machine of FIG. 1 includes a supporting beam 1 which is 
assembled from a plurality of adjoining sections 2, 3. Each of the 
sections 2 is fitted at its upper side with a mower member 4 capable of 
rotation about a substantially upwardly directed shaft. The mower member 4 
includes a disc-shaped portion having at its outer periphery one or more 
knives 5. In addition, each of said sections 2 of the supporting beam 1 is 
provided with a slide shoe 6, which slides over the soil during operation. 
In addition, the mowing machine is provided with a frame 7 which is 
connected to the two ends of the supporting beam 1 and extends rearwardly 
and thereafter upwardly from said connecting points, a hollow tube 8 
constituting part of the said frame. The hollow tube 8 has both its ends 
connected to gear boxes 9, 10, which are mounted rigidly in said frame 7. 
A main drive shaft 11, which at both ends is provided with a bevel gear 
wheel 12, 13, each of which is accommodated in one of the gear boxes 9, 10 
is located inside the said hollow frame tube 8. The said bevel gear wheels 
12, 13 mesh with respective bevel gear sheels 14, 15 mounted on respective 
secondary drive shafts 16 and 17. Said secondary drive shafts 16, 17, 
whose other ends are connected to the two outermost mower members 4, are 
each divided into three sections by means of universal joints 18, 19, 20 
and 21. 
As is apparent from FIG. 2, the universal joints 18, 19 are single ones in 
this embodiment. A crop guide member 22, in the shape of a substantially 
cylindrical drum, is connected to the middle section of the drive shaft 
16, 17. The said drum-shaped crop guide member 22 rotates along with the 
drive shaft 16 and hence with the mower member 4, which is provided with 
an edge 23 that is contiguous to the drum-shaped crop guide member 22. At 
its upper side, the drum-shaped crop guide member 22 is contiguous to a 
screening hood 24 fitted to the frame 7. 
A bevel gear wheel 25, by which the main drive shaft can be driven, is 
mounted on the main drive shaft 11. To that end, the bevel gear wheel 25 
meshes with a gear wheel 26 which is connected, for example, via the 
necessary intermediate shafts to the power take-off shaft of a tractor. A 
trestle 27 attached to the hollow tube 8 of the frame 7 provides the means 
to hitch the mowing machine to a tractor. 
As has been described in the foregoing, the two outermost mower members 4 
of the supporting beam 1 are driven via the main drive shaft 11 and the 
two secondary drive shafts 16 and 17. The supporting beam 11 accommodates 
a torsion shaft 30 (FIG. 2) which has a substantially square cross-section 
and extends substantially through the entire supporting beam. In each of 
the sections 2 of the supporting beam 1, the torsion shaft 30 is provided 
with a gear wheel, which has a square center-hole corresponding to the 
cross-section of the torsion shaft 30. Each gear wheel is mounted on the 
torsion shaft so that it might slide in the longitudinal direction but is 
rigidly secured against rotation. The gear wheel in each of the sections 2 
of the supporting beam 1 drives the mower member 4 mounted on the relevant 
section 2. Consequently, all the mower members 4 are interconnected by 
means of torsion shaft 30 in a flexible manner, i.e. the torsion shaft 30 
functions as a torsion spring between every two adjacent mower members. 
The use of this flexible connection allows for direct drive of the two 
outermost mower members, driving each of the further mowing members via 
the outermost mower members in dependence on the load distribution of the 
mowing machine. 
The component sections 2, 3 of the supporting beam are kept together by a 
tensile rod 31 (FIG. 2) which extends through recesses in each of said 
sections 2, 3 and is provided at its ends with thread, so that by 
tightening nuts provided thereon the component sections 2, 3 are drawn up 
against each other and hence constitute one integral whole. In addition, 
the tensile rod 31 can extend through sections of the frame 7, so that the 
supporting beam 1 is fixed in the frame 7. 
Although in FIG. 1 there is shown a trestle 27 for coupling the mowing 
machine to either the rear or front of a tractor, the mowing machine may 
alternatively be provided with wheels and be drawn by a hauling vehicle or 
it may be mounted in an implement in which there are, for example, also 
provided means for processing the mown crop. In this use, the main drive 
shaft 11 may alternatively be driven near one of its ends. 
The embodiment shown in the FIGS. 4 and 5 differs from the one described in 
the foregoing by the absence of universal joints in the drive shafts 16, 
17. In addition, there are lacking frame portions to couple the supporting 
beam 1 to the superjacent portion of the frame, i.e. the hollow tube 8. 
The supporting beam 1 is mounted only by means of drive shafts 16, 17 
which are bearing 32 supported in the superjacent frame portion. The drive 
shafts 16, 17 have their other end rigidly connected to the outermost 
mower members 4 on the supporting beam. Such a construction has the 
considerable advantage in that it prevents the so-called "piling" of the 
crop, i.e. the accumulation of crop against stationary frame portions. 
Also the embodiment shown in FIGS. 4 and 5 can be connected by means of a 
trestle 27 to a vehicle or be accommodated in a mowing machine which is 
drawn by a vehicle and wherein optionally also additional crop processing 
members, such as a crusher, are incorporated. 
It will be obvious that the use of the above-described drive of the mower 
members, whereby the two outermost mowing members are driven directly and 
all the interposed mower members are interconnected in a flexible manner, 
allows for the advantageous distribution of the forces when, for example, 
one of the central mower members is all of a sudden loaded heavily, which 
extra load need only be taken in part by either of the drive shafts 16, 
17. Therefore, an improved distribution of the drive forces is the result 
of the construction as described. 
The invention is not limited to the features described in the foregoing and 
as claimed in the claims but also comprises any combination of measures as 
described in the description and as illustrated in the drawings.