Note: Descriptions are shown in the official language in which they were submitted.
12
273~2-2/
The present invention relates to a quick-acting coupling
for the simultaneous connection of agricultural machinery to
the drawbar system and the the power takeoff connector of a
tractor, this consisting of a coupling frame that is
permanently mounted on the drawbar system and a connector
frame that is permanently mounted on the machinery, and of a
drive-shaft stub that is connected to the power takeoff of
the tractor by means of a cardan shaft, particularly a
cardan shaft that can be adjusted for length, and a locking
system that locks the coupling frame to the connector frame,
the coupling frame that is permanently connected to the
tractor hydraulic system being in the approximate shape of
an equilateral triangle and having a bearing for the drive-
shaft stub; the connector frame that is arranged on the
machinery is formed as an approximately equilateral
triangular counterframe, with the apex of the coupling frame
and the apex of the connector frame being uppermost./
~ coupling of this kind is known, for example, from
DE-OS 2031 ~63. In this system, the triangular frames are
U-shaped, and the coupling frame has to be slid into the
connector frame, attached to the machinery, from below. The
two coupling members are connected rigidly to the frame, and
, ~,
4~
this results in the disadvantage that it is impossible to
move the coupling members relative to the particular
associated frame./
Thus, however, it is practically impossible to perform
a coupling operation by simply driving the tractor up to the
machinery that is to be coupled to it, since on the one hand
the tractor must driven beneath the machinery to which it is
to be coupled, while at the same time the two coupling
members must be aligned axially with each other. In
addition, it must also be borne in mind that the coupling
frame of the tractor must be driven up almost vertically in
the frame of the machinery, which results in difficulties
with the projecting portions of the drive shaft coupling./
According to EP-OS 63 533 a coupling frame for a
tractor w~th an associated connector frame on the machinery
is already known. In its upper, roof-like portion this
consists of U-sections into which the upper portion of the
coupling frame is introduced. For this reason, in order to
join the two frames, they must first be in contact, when the
coupling frame is inserted into the U-section of the
connector frame by being raised. To this end, of course,
both frames must be exactly parallel./
Finally, DE-OS 330~ 588 describes a quick coupler for
field tractors, this having a coupling frame that is
attached to a drawbar device having a quick-coupliny hook
that is open on top./
~L~7~
It is the aim of the present invention to avoid the
disadvantages set out above and to propose a coupling of the
type described, which permits rapid and secure coupliny by
driving the tractor up to the machinery in question./
This has been achieved according to the present
invention in that the connector frame, which has a cross-
section that is in particular box-like, has projections
and/or flanges that protrude in the direction of the tractor
only on two of the triangle sides that extend from the apex,
and which, in order to provide for shape-locking coupling of
the coupling frame with the connector frame is pushed over
the side surfaces of the coupling frame, and that an
approximately horizontal cross-piece that is displaced
towards the connector frame is provided to support a drive
shaft dog clutch with push-type connectors for the
hydraulic, pneumatic, and electrical system connectors.
Thus, it becomes possible to drive the frame of the tractor
in an axial direction into the frame of the machinery,
whereupon the frames are centred by the projecting flange
and by the displaced cross-piece. The cross-piece that is
displaced towards the connector frame and which supports the
drive shaft dog clutch also makes it possible to incorporate
a longer power takeoff shaft. Because of the dog clutch it
is possible to achieve an immediate connection with the
'
~L2~
drive shaft of the machinery when the coupling frame is
slid onto the connector frame, and to do this without the
use of additional aids./
It is preferred that the apex of the coupling frame,
which extends beyond the cross-piece, be provided in the
already familiar manner with a rotating roller, the axis of
which is perpendicular to the direction of coupling of the
two frames. It is made significantly easier to introduce
the coupling frame into the apex of the connector frame by
the use of such a roller./
Connection of the two frames is further simplified by
the fact that the flanges on the connector frame in the
vicinity of the upper apex are joined to each other so as to
form a run-up surface for the roller that is secured to the
coupling frame. In order to ensure a secure connection of
the two frames, all that has to happen is that the coupling
frame with its attached roller has to move up the run-up
surface, whereupon the roller reduces the friction that is
generated./
Another advantageous version of the present invention
is seen in the fact that in its lower, free end area the
run-up surface has an inclined face that is oriented in the
direction of the coupling frame. This inclined surface
makes it much simpler to insert the coupling frame with the
roller, and slight displacements of the two frames cause no
hindrance to the coupling procedure./
. .
Finally, there is another advantageous version of the
present invention in that slip coupling with an adjustable
compression spring is supported on the cross-piece of the
coupling frame as a coupling for the drive shaft; the
greatest possible security for the machinery and the
greatest possible use of said machinery by means of suitable
adjustment of the spring pressure on the coupling drum that
can be slid along the drive shaft./
The present invention will be described on the basis of
an exemplary version that is illustrated in the drawings
appended hereto. These drawings show the following:/
Figure 1: A view of the front of a tractor with a coupling
frame (in partial cross-section);/
F`igure 2: A view of the coupling frame;/
Figure 3: A cross-section through the coupling frame;/
Figure 4: A drawing as in Figure 1, although with the
connector frame of a mowing machine;/
Figure 5: A view of the connector frame for the mowing /
machine;/
Figure 6: A cross-section through the connector frame as /
in Figure 5;/
Figure 7: A perspective view of the tractor with the /
coupliny frame;/
Figure 8: A front view of the coupliny frame with a locking/
system;/
... . ..
Figure 9: A side view of the coupling frame;/
Figure 10: A dog clutch;/
Figure 11: A conical sliding coupling.
Figure 1 shows the front of a tractor with the tractor
hydraulic system 1 that consist of a three-point lifting
device intended for coupling machinery. This three-point
lifting device consists of an upper control arm 4 that can
be ad~usted for length, and two lower control arms 3. These
support a coupling frame 4, the connection between them
being by means of link pins. The lifting frame is in the
form of an equilateral triangle, the apex of which is
uppermost. At its apex the coupling frame 4 has a roller 5
that is supported on a shaEt that is perpendicular to the
direction of the coupling in such a manner as to be able to
rotate. In the lower third of the coupling frame there is a
horizontal cross-piece 6 that supports a drive-shaft dog
clutch 8 and accomodates the necessary push-type connectors
8' for hydraulic, pneumatic and electrical systems. The
drive shaft dog clutch 8 is driven by a cardan shaft 9,
which can be adjusted for length, from the tractor's power
takeoff connector 10./
As can be seen from Figure 3, the coupliny frame 4 has
a box-like cross-section./
Fiyures 4 and 5 show the associated connector frame 10'
that is permanently attached to the front-mounted mower
assembly 23. This has a sliding coupling 24 that
incorporates a spring that can be adjusted for pressure.
The connector frame 10' is also configured as an equilateral
triangle and is of a size that is e~ual to the coupling
frame 4, and has a similar box-like cross-section (Figure
6). On both sides of the connector frame 10' there are
flanges 20 that project in the direction of the coupling
frame 4; these are connected in the area of the apex by an
run-up surface 20 that makes it possible to drive the
assembly under and hook onto the coupling frame 4 with its
roller 5./
In its lower area the run-up surface 21 has a sloping
surface 22 that is inclined in the direction towards the
coupling frame 4. At the same level as the coupling frame
4, on the connector frame 10', there are also installation
possibilities for connectors for the hydraulic, pneumatic,
and electrical systems./
The coupling of machinery to the control arms 2,3 of
the tractor drawbar hydraulic system is done such that the
coupling frame 4 is completely lowered and the apex with the
roller is positioned correctly, from behind, in the opening
of the connector frame 10' or behind the run-up surface 21,
when the hydraulic [drawbar--Translator] is raised and the
upper control arm is retracted, whereupon the components are
locked in this position. In this way the machinery in
question can be coupled up without any intervention by the
operator seated on the tractor./
The locking system 11 consists of a double-acting
cylinder 12, preferably a hydraulic cylinder, which is
connected to the coupling frame 4; this cylinder has two
piston rods, the free ends of which are supported in the
guldes 13 on the lower ends of the triangle sides of the
coupling frame 4. In a similar way, there are projections
14 on the connector frame 10' and these can be introduced
into the guides 13; the piston rods can pass through these
projections. The hydraulic cylinder incorporates a
compression spring, the purpose of which is to retain the
piston rods in the locking position. In order to unlock the
assembly the two chambers of the cylinder 12 are pressurized
through a pressure line, whereupon the piston rods are
withdrawn from the guides to the point that the projections
can be introduced into the guides or withdrawn from these.
When the locking system 11 according to the present
invention is used a mower or the harvester can be coupled at
the front and the wagon can be coupled to the rear since the
machinery in question can be coupled or uncoupled very
quickly, without the operator having to dismount from the
tractor./
