Patent Description:
Agricultural vehicle such as tractors are provided with connections means for allowing the connection of a trailer to the tractor. Indeed, tractor-trailer combinations are widely known and used for a plurality of different working operations both in the fields and on road.

The aforementioned connection means are usually provided in form of a pick-up hitch assembly. Such assembly may be realized in different known ways to define a connection between the tractor and the trailer as shown for example in <CIT>.

Briefly and making reference to <FIG>, a known pick-up hitch assembly 1a' comprises a cassette <NUM>' configured to carry in movable manner a first hitch point element <NUM>'. Such cassette <NUM>' is carried by tractor's body in a movable manner, usually by a hinge connection <NUM>' realized in its inner portion with respect to the tractor. Accordingly, the first hitch point element <NUM>' is carried on an outer portion opposed with respect to the inner portion and it is configured to move up and down according to the circumferential path defined by the aforementioned hinge connection <NUM>'.

Further making reference to <FIG>, a known lift assembly 1b' comprises a pair of hydraulic cylinders <NUM>' having a first extremity connected to a cantilever arm <NUM>' hinged at one extremity portion to an upper portion of the vehicle and a second extremity connected to the outer portion of the cassette <NUM>'.

The lift assembly 1b' comprises two lateral arms <NUM>', comprising a first portion hinged to the tractor's body and a second portion carrying respectively a second and a third hitch point elements <NUM>' for further connecting the tractor with the trailer.

The two lateral arms <NUM>' are furthermore connected to the cantilevered arm <NUM>' via a mechanical tie rod <NUM>' which is hinged in an intermediate position with respect to the extremities portions of each of the lateral arms <NUM>' and the cantilevered arm <NUM>'.

The pick up hitch assembly 1a' and the lift assembly 1b' are linked in some operational conditions via a pair of telescopic arms <NUM>' hinged at their extremities to respectively a portion of cassette <NUM> comprised between hinge <NUM> and first hitch element <NUM>' and to the extremity of the cantilevered arm <NUM>' opposite to the one hinge to tractor's body.

In a first operational condition, cassette <NUM>' is maintained fixed to tractors' body, e.g. thanks to a mechanical lock <NUM>' and therefore the telescopic arms do not interfere with the normal movement of the operation of lifting cylinders <NUM>.

In a second operational condition, mechanical lock <NUM>' leaves cassette <NUM> moving and therefore, it is transported by telescopic arms <NUM>' are configured to allow the movement of cassette <NUM>' about hinge <NUM>', in function of their extension or retraction with respect to cantilevered arm <NUM>'.

Furthermore, even if not clearly visible from figure <NUM>', the vehicle comprises a Power Take Off (PTO) <NUM>' usually positioned in a substantially centered position with respect to telescopic arms10' and with respect to vehicle's body.

Accordingly to the preceding described geometry and as clearly shown in <FIG>, such telescopic arms <NUM>' are laterally comprised with respect to lateral arms <NUM>' and are vertically spaced across all the extension of the pick-up hitch assembly <NUM>'.

Therefore, it is undoubted that telescopic arms <NUM>' occupy a consistent space in rear of the a tractor, reducing accessibility and freedom of operation in such an important area.

According to the above, the need is felt to provide a rear control assembly which can accomplish to all standard maneuvers of lateral lifting arms and pick-up hitch assembly via a reliable, compact, robust and economic control system.

An aim of the present invention is to satisfy the above mentioned needs in an economic and optimized manner.

The aforementioned aim is reached by an agricultural vehicle comprising a pick-up hitch assembly as claimed in the appended set of claims.

<FIG> discloses an exemplarily embodiment of a rear connection assembly <NUM> according to the invention configured to connected a work vehicle <NUM>, e.g. a tractor, to an trailer (not shown) to define a tractor-trailer combination. As per se known, pick-up hitch assembly <NUM> is carried by a vehicle's body 2a, preferably beneath the vehicle and more preferably in a rear side of this latter.

In particular, connection assembly <NUM> comprises a cassette <NUM> configured to carry a first hitch point element <NUM> and a pair of lateral arms <NUM> configured each to carry a respective coupling element <NUM>. Hitch point elements may be of any typology, e.g. comprising drawbars, hooks or ball coupling elements and are configured to allow the connection of a corresponding mating element carried by the trailer.

In further detail, cassette <NUM> is a standard pick-up hitch cassette and has a substantially parallelepiped shape and is hinged at a rear portion 3a via a first hinge <NUM> underneath vehicle's body 2a and carry the first hitch point element <NUM> at a front portion 3b opposite with respect to the rear portion 4a. Accordingly, the first hitch point element <NUM> may move about a circumferential path about an axis A defined by first hinge <NUM>.

Lateral arms <NUM> are known lifting assembly arms and each comprises an inner portion 5a connected to vehicle's body 2a via a second hinge <NUM> and an outer portion 5b, opposite with respect to the inner portion 5a. Accordingly, such lateral arms <NUM> may each move about a circumferential path about an axis B defined by second hinge <NUM>.

Each lateral arm <NUM> is furthermore connected to a respective cantilever arm <NUM> connected to an upper portion of vehicle's body. In particular, each cantilever arm <NUM> comprises an inner portion 11a connected to vehicle's body 2a via a third hinge <NUM> and an outer portion 11b, opposite with respect to the inner portion 11a. The connection of each lateral arm <NUM> is realized between this latter and the outer portion 11b of the respective cantilever arm <NUM> via a connection element <NUM>.

Furthermore, the movement about third hinge <NUM> of cantilever arm <NUM> is substantially free towards the opposite with respect to tractor's body <NUM>, while it is limited on the opposite direction thanks to stop means <NUM>, e.g. an abutment carried by tractor's body <NUM>, into which the respective cantilever arm <NUM> may be supported when reached its maximum downwards extension.

The connection element <NUM> is preferably a mechanical damper comprising an upper portion 13a hinged with respect to the outer portion 11b and an inner portion 13b hinged with respect to the lateral arm <NUM> in an intermediate position between his inner and outer portions 5a, 5b. According to the described geometry, lateral arms <NUM> may be lowered or lifted according to the movement of outer portion 11b of cantilever arm <NUM> which follows a path around an axis C defined by third hinge <NUM>. It is specified that connection element <NUM> simply connected, in a damped or non-damped way, the two elements but it is not an active actuator for moving lateral arms <NUM>.

Indeed, rear connection assembly <NUM> further comprises actuation means <NUM> operatively interposed between each lateral arm <NUM> and the respective cantilever arm <NUM> and configured control the movement of lateral arms <NUM>. In particular, actuation means <NUM> may comprise an actuator cylinder <NUM>, better a hydraulic cylinder, comprising a casing 16a and a stem 16b.

The stem 16b of actuator cylinder <NUM> is connected in a terminal portion to cantilever arm <NUM> via fourth hinge <NUM> between its inner and outer portions 11a, 11b while the casing 16a of actuator cylinder <NUM> is connected via fith hinge <NUM> to a portion 2a of said vehicle <NUM> via the locking element <NUM>. Advantageously, actuator cylinder <NUM> is a double acting cylinder.

Preferably, rear connection assembly <NUM> may comprise locking means <NUM> configured to lock fourth hinge <NUM>, i.e. to rigidly couple the terminal portion of stem 16b with vehicle's body 2a. Preferably, locking means <NUM> are integrated into fourth hinge <NUM>. Locking means may be alternatively mechanically actuated means, e.g. a pin to be inserted manually into a hole, or electrically/automatically actuated means, i.e. comprising an actuator controller by an electronic control unit to selectively lock or unlock fourth hinge <NUM>.

According to a further aspect of the invention, the casing 16a of actuator cylinder <NUM> is furthermore connected in a terminal portion via fifth hinge <NUM> to cassette <NUM> in an intermediate position comprised between its rear and front portions 3a, 3b.

In particular, as better appreciated in <FIG> and <FIG>, the connection of casing 16a to cassette <NUM> is realized via a joint element <NUM>, e.g. flange having a predefined shape. Such joint element <NUM> essentially comprises a first portion 21a hinged to fifth hinge <NUM> and a second portion 21b coupled to cassette <NUM> via a mechanical coupling <NUM>.

Preferably, the mechanical coupling <NUM> is realized between a pin <NUM> preferably carried by joint element <NUM> and a guide <NUM> realized carried by cassette <NUM>. The guide <NUM> has a shape configured to compensate both horizontal and vertical displacement of joint element <NUM> during the movement defined hereinafter and linked to movement of cassette <NUM> with respect to vehicle's body 2a.

According to a further aspect of the invention, fifth hinge <NUM> comprises locking means <NUM> configured to lock fifth hinge <NUM>, i.e. to rigidly couple the terminal portion of casing 16a to vehicle's body 2a. Similarly to what stated for locking means <NUM>, also locking means <NUM> may be alternatively mechanically actuated means, e.g. a pin to be inserted manually into a hole, or electrically/automatically actuated means, i.e. comprising an actuator controller by an electronic control unit to selectively lock or unlock fifth hinge <NUM>.

In the exemplarily described embodiment, locking means comprises a triangular element <NUM>, e.g. a plate-like element comprising three vertexes 26a, 26b, 26c. A first vertex 26a is coupled to casing 16a via fifth hinge <NUM>, a second vertex 26b is coupled to vehicle's body via a sixth hinge <NUM> and a third vertex 26c is selectively coupled to vehicle's body 2a via locking means <NUM>. When the third vertex 26c is coupled, triangular element <NUM> cannot move with respect to vehicle's body, being fixed in second and third vertexes 26b, 26c; conversely, when third vertex 26c is uncoupled, triangular element <NUM> can move with respect to vehicle's body, since it can move about an axis D defined by sixth hinge <NUM> of second vertex 26b.

Advantageously, elements <NUM> and <NUM> are fixedly coupled together and, preferably, are realized as one piece.

The rear connection assembly <NUM> further comprises a control circuit (not shown) configured to control actuation means <NUM> and, when not actuated manually, locking means <NUM>, <NUM>. According to the described embodiment, the control circuit may comprise a hydraulic portion configured to control the actuator cylinder <NUM> and a hydraulic/pneumatic or electric portion configured to control locking means <NUM>, <NUM>.

The operation of the rear connection assembly <NUM> described above is the following.

In a first operation mode, both locking means <NUM> and <NUM> maintain fixed the position of actuator cylinder <NUM> and the position of cassette <NUM> and arms <NUM> is fixed.

In a second operation mode, i.e. a lateral arms moving phase, locking means <NUM> lock element <NUM> with respect to vehicle's body. At the same time, locking means <NUM> maintain free the movement of fourth hinge <NUM>. Accordingly, making reference to <FIG>, current position P' of fifth hinge <NUM> cannot be modified and is maintained fixed by triangular element <NUM> which is fixed in vertexes 26b, 26c. Accordingly, a retraction or an expansion of actuator cylinder <NUM> can move only lateral arms <NUM> via cantilevered arm <NUM>, thereby lowering or lifting second and lateral arms <NUM>.

In a third operation mode, i.e. a cassette moving phase, when cylinder <NUM> is totally retracted and therefore cantilever arm <NUM> is supported on stop means <NUM> while locking means <NUM> allow movement of third vertex 26c of triangle element <NUM>. It is noted that the weight of the system is sufficient to lock the position of the fourth hinge <NUM>. However, advantageously, locking means <NUM> can be provided to definitively lock fourth hinge <NUM>.

According to the above configuration, making reference to <FIG>, current position P'' of fourth hinge <NUM> cannot be modified and is maintained fixed with respect to vehicle's body 2a; therefore also cantilevered arm <NUM> cannot move and lateral arms <NUM> consequently. Accordingly, a retraction or an expansion of actuator cylinder <NUM> can move joint element <NUM>, which is linked to element <NUM> which can move freely about axis D sixth hinge <NUM>. Thus, thanks to mechanical coupling <NUM>, cassette <NUM>, which is carried by joint element <NUM>, can move about first hinge <NUM> thereby lowering or lifting first cassette <NUM>, i.e. point hitch element <NUM>, which can be furthermore be extracted or retracted by cassette <NUM>, as per se known.

In view of the foregoing, the advantages of an agricultural vehicle comprising a pick-up hitch assembly <NUM> according to the invention are apparent.

First, the proposed pick-up hitch assembly <NUM> avoid the use of the long support rods as known in the known pick-up assemblies thereby decreasing its encumbrance.

Again, the control of the pick-up hitch element is simpler since only the actuator cylinder <NUM> can be controlled to regulate the movement of both lateral arms <NUM> and cassette <NUM>. Furthermore such control can be implemented without the interference of the lift arms, differently from the prior art.

Furthermore, in view of the absence of support rods, the cantilevered arm can be realized shorter and lighter, thereby further reducing the dimension of the pick-up hitch assemblies and of cylinder actuator <NUM>.

It is clear that modifications can be made to the described agricultural vehicle comprising a pick-up hitch assembly <NUM> which do not extend beyond the scope of protection defined by the claims.

For example, it is clear that the proposed described arrangement of pick-up hitch assembly is merely exemplarily and may comprise different elements and may have a different shape.

Claim 1:
Rear connection assembly (<NUM>) for an agricultural vehicle (<NUM>) comprising:
a cassette (<NUM>) connectable via a first hinge (<NUM>) to a portion (2a) of said vehicle (<NUM>) and configured to carry a first hitch point element (<NUM>);
a pair of lateral arms (<NUM>) each connectable via a second hinge (<NUM>) to said portion (2a) of said vehicle and each configured to carry respective further hitch point elements (<NUM>),
wherein said hitch point elements (<NUM>, <NUM>) being configured to allow the connection with corresponding elements carried by a trailer in order to be trained by said vehicle,
a pair of cantilevered arms (<NUM>) connectable via a third hinge (<NUM>) to said portion (2a) of said vehicle and each positioned above the second hinge (<NUM>) of the respective lateral arms (<NUM>),
a pair of connection elements (<NUM>), each connection element (<NUM>) connecting a respective cantilevered arm (<NUM>) together with the corresponding lateral arm (<NUM>),
actuation means (<NUM>) interposed between each cantilevered arm (<NUM>) and the respective lateral arm (<NUM>),
wherein each actuation means (<NUM>) is connected via respective fourth and fifth hinges (<NUM>, <NUM>) to the cantilevered arm (<NUM>) and the portion (2a)of said vehicle,
the assembly is characterized in that said rear connection assembly (<NUM>) further comprises locking means (<NUM>, <NUM>, <NUM>) for selectively locking the position of said fourth and fifth hinges (<NUM>, <NUM>) with respect to said vehicle body (2a) and a joint element (<NUM>) connecting together said fifth hinge (<NUM>) to said cassette (<NUM>).