The invention relates to a system for removing manure from a floor in a barn for keeping animals, such as manure from cows, with an electrically driven, autonomous manure removing vehicle. "Removing manure" comprises not only the taking up of manure from a floor, for example by sucking up, picking up, scooping up and the like, but also the moving of manure over a floor with slotted holes, i.e. a "grid floor" or "slatted floor", in order to remove the manure to a manure reservoir beneath the floor. In the case of a grid floor, the manure can be removed from the floor by moving the manure through the slotted holes, so that the manure drops into the manure reservoir or manure pit beneath the floor.

The Lely Discovery 120 Collector ® is known. This is an autonomous manure removing vehicle for removing manure from the floor of a barn. The vehicle is located in a very contaminated environment among the animals in the barn, as a result of which during operation the vehicle becomes very contaminated with manure and urine from the animals, and for example also with straw, sand and/or sawdust from the barn. The vehicle can find its way autonomously by means of an electronic control system with sensors, such as an ultrasonic sensor and a gyroscope. On the basis of the signals detected by the sensors, the control system controls a drive system with electric drive motors for the wheels of the vehicle. Consequently, the vehicle can be steered and can travel along a desired route. The drive system and the control system are powered by a battery system on board the vehicle. The battery system is connected to electrically conductive charging strips that extend on the outside of the vehicle. In order to charge the battery system, the vehicle travels to a charging station with charging electrodes. In the charging station, the vehicle maneuvers in such a way that the charging strips on the outside of the vehicle make contact with the charging electrodes of the charging station, and charging current can be supplied to the battery system.

However, the charging current is limited for reasons of safety. When the charging strips of the vehicle make contact with the charging electrodes of the charging station there is a risk of an electric spark, while explosive manure gases may be present in the vicinity of the charging station. The charging current is limited to prevent an electric spark leading to an explosion. However, the lower the charging current, the longer it takes to charge the battery system. Therefore charging takes a relatively long time, which adversely affects the capacity (in liters of manure removed per day). It is an object of the invention is to provide an improved system for removing manure from a floor in a barn with animals, wherein in particular, charging of the autonomous manure removing vehicle takes less time and at the same time reliability remains ensured.

This object is achieved according to the invention by a system for removing manure and/or urine from a floor in a barn for keeping animals, such as dairy cows, cows for meat production, pigs or goats, said system being provided with:

• an autonomous manure removing vehicle for removing manure and/or urine from the floor in the barn, wherein the vehicle comprises

- a drive system for driving the manure removing vehicle, said drive system being provided with at least one electric drive motor,

- an electronic control system, which is connected to the drive system for control thereof,

- a battery system for storing electrical energy, said battery system being connected to the drive system and the control system,

• a charging station for charging the battery system of the manure removing vehicle, wherein the charging station comprises a transmitting body with a primary coil, and the manure removing vehicle comprises a receiving body with a secondary coil, wherein the receiving body is fastened rigidly to the manure removing vehicle, and wherein the transmitting body of the charging station is pretensioned to a waiting state or initial state, for example by means of a spring device, and is movable from the waiting state against the action of the pretension, through engagement with the receiving body of the manure removing vehicle that enters the charging station in a direction of travel, in such a way that the primary coil of the transmitting body and the secondary coil of the receiving body are mutually aligned in a charging state to transfer electrical energy wirelessly from the primary coil to the secondary coil for wireless charging of the battery system of the manure removing vehicle.

The manure removing vehicle according to the invention is configured to follow autonomously at least one route among the animals in the barn. If it is desired to charge the battery system, the manure removing vehicle travels to the charging station. The charging station defines a charging position for the manure removing vehicle during charging of the battery system. If the vehicle is located in the charging position, according to the invention the primary coil of the transmitting body of the charging station and the secondary coil of the receiving body of the manure removing vehicle can be mutually aligned for wireless energy transfer between them.

In particular, the transmitting body comprises a transmitting plate with the primary coil. The transmitting plate is for example arranged adjacent to a flat surface of the transmitting body. The receiving body may comprise a receiving plate with the secondary coil, wherein the receiving plate is arranged for example adjacent to a flat surface of the receiving body. The transmitting plate and the receiving plate may each be formed by a round disk ("charging pad"), in particular with a diameter from 10 to 30 cm and/or a thickness from 1 to 2 cm. The transmitting body and the receiving body with such a "charging pad" may have another suitable shape, such as a droplet shape, a rectangular shape or some other. The primary and secondary coils may each comprise one or more induction coils, for example a stack of induction coils. The term "coil" is to be understood as meaning a device that comprises one or more induction coils. In particular, in the charging state, the primary coil of the transmitting body and the secondary coil of the receiving body are at a distance apart that is less than 5 cm, preferably less than 3 cm, such as substantially 2 cm or less. In that case efficient wireless energy transfer is possible.

With the wireless charging system according to the invention, the risk of an electric spark has disappeared. During wireless transfer of electrical energy from the transmitting body to the receiving body, there cannot be any spark formation, which in the presence of explosive manure gases could lead to dangerous situations. Therefore it is possible according to the invention to increase the charging current without compromising safety. Therefore charging of the autonomous vehicle takes less time, so that the vehicle has more time to drive around for carrying out the manure removal task. This increases the capacity (liters of manure removed per day).

At the same time, the reliability of charging of the autonomous manure removing vehicle is guaranteed. The manure removing vehicle can be maneuvered to some extent in the charging position, i.e. within the charging station, to move the receiving body relative to the transmitting body of the charging station. Nevertheless, it is difficult to align the primary coil of the transmitting body and the secondary coil of the receiving body just by controlling the manure removing vehicle. For wireless energy transfer it is important to align the primary coil of the transmitting body and the secondary coil of the receiving body (very) accurately relative to each other, in particular to an accuracy of cm order of magnitude, for example as already mentioned above to a distance apart of max. 2 cm or less.

For this purpose, according to the invention the transmitting body is movable relative to the charging station, whereas the receiving body is fastened rigidly to the manure removing vehicle. In other words, the freedom of movement for alignment is fully realized on the side of the transmitting body of the charging station, and the receiving body has no moving parts. Therefore the adverse effect of manure and other fouling on the alignment is minimized. Since the manure removing vehicle travels around among the animals in the barn, the manure removing vehicle is more liable to fouling with manure than the charging station, which is located at a fixed position in the barn or even outside the barn. It is then advantageous that the receiving body of the manure removing vehicle has no moving parts that are extra sensitive to faults through the action of manure.

In addition, the transmitting body of the charging station is pretensioned to the waiting state, i.e. the transmitting body is located in the waiting state always in the same accurately defined position. The transmitting body always returns to the same position when the manure removing vehicle has left the charging station. Therefore, for alignment, the transmitting body always begins at the same position. As a result, the manure removing vehicle can travel into the charging station in such a way that the receiving body can reliably engage each time on the transmitting body in the waiting state. Moreover, it is favorable that through engagement of the receiving body on the transmitting body, these two charging bodies come into contact with each other. It is therefore guaranteed that the primary coil of the transmitting body and the secondary coil of the receiving body can be mutually aligned with the desired accuracy for reliable and efficient wireless charging of the battery system of the manure removing vehicle.

In an embodiment, the receiving body and the transmitting body are adapted to each other in such a way that when the manure removing vehicle enters the charging station in the direction of travel, the receiving body of the manure removing vehicle engages on the transmitting body of the charging station to entrain the transmitting body from the waiting state in the direction of travel, wherein the transmitting body is arranged to the charging station in such a way that on entrainment of the transmitting body in the direction of travel, the transmitting body is movable relative to the charging station in a direction transverse to the direction of travel and/or in the vertical direction. When the transmitting body is entrained in the direction of travel, the transmitting body may perform a motion of translation relative to the charging station in a direction transverse to the direction of travel and/or in the vertical direction. In this case the transmitting body is movable according to two or three degrees of freedom for translation. The transmitting body can move not only in the direction of travel, but also transverse to the direction of travel in order to be accurately aligned relative to the receiving body of the manure removing vehicle.

It is also possible that on entrainment of the transmitting body in the direction of travel, the transmitting body is rotatable relative to the charging station about a substantially vertical rotation axis and/or about a substantially horizontal rotation axis that is parallel to the direction of travel and/or about a substantially horizontal rotation axis that runs in a direction transverse to the direction of travel. In this case the transmitting body is also movable according to at least one degree of freedom for rotation. In particular, the transmitting body is at least rotatable relative to the receiving body while the transmitting body and the receiving body are substantially parallel to each other. If the transmitting body is for example on top of the receiving body, the transmitting body can then swivel about a substantially vertical swivel axis.

It is preferable according to the invention for the transmitting body of the charging station in the waiting state to abut against a front stop, which defines a front position, and wherein the transmitting body is movable from this front position over a length in the direction of travel to a rearmost position, wherein the rearmost position for example is defined because the manure removing vehicle comes up against a stop of the charging station, and wherein the transmitting body is arranged substantially freely movably to the charging station between the front and rearmost position, i.e. over said length. "Freely movable" is understood to mean that the transmitting body is movable relative to the charging station between the front stop and the rear stop in order to adjust the position and orientation of the transmitting body to the receiving body of the manure removing vehicle while the manure removing vehicle enters the charging station and the receiving body engages on the transmitting body.

In an embodiment the receiving body and the transmitting body are configured in such a way that in the charging state the flat surfaces of the transmitting body and the receiving body press against each other, i.e. exert a compressive force on each other, in particular under the effect of the pretension and/or gravity. When the manure removing vehicle enters the charging station, the receiving body pushes the transmitting body out of the waiting state. In other words, the transmitting body is moved from the waiting state through engagement with the receiving body, against the action of the pretension and/or gravity. In consequence, in the charging state the flat surfaces are pressed against each other. The compressive force created by the pretension may be so great that manure or other fouling that is possibly present on the receiving body is squeezed out at least partially from between the flat surfaces. Nevertheless, wireless energy transfer is even possible if there is still manure between the flat surfaces - provided that the distance between the primary and secondary coil is small enough, energy can be transferred wirelessly through the manure. This is ensured by pressing the flat surfaces of the transmitting body and receiving body on each other.

In an embodiment, the receiving body comprises, on a front side thereof, a centering edge, which projects substantially transversely from an outermost wall of the manure removing vehicle, wherein the centering edge surrounds the receiving plate of the receiving body at least partially, and wherein the receiving plate defines a central axis, which in particular runs parallel to the direction of travel, and on either side of the central axis, the centering edge deviates transversely from the central axis in a direction opposite to the direction of travel, i.e. backwards, and wherein the transmitting body is configured in such a way that the transmitting body and the centering edge engage on each other as the manure removing vehicle enters the charging station in the direction of travel, so that the primary coil of the transmitting body and the secondary coil of the receiving body are mutually aligned in the charging state. The receiving body is fastened to an outermost wall of the manure removing vehicle and projects relative to said outermost wall. The vertical collar, which projects from the outermost wall, forms the centering edge. The centering edge runs at least partially around the receiving plate. The centering edge runs backwards away from the central axis of the receiving plate, which extends through the center of the receiving plate and substantially parallel to the direction of travel. As a result, it is possible to align reliably into the charging state in the (very) contaminated barn environment, even if the manure removing vehicle enters the charging station somewhat obliquely. Furthermore, the forces are well distributed and are led away on mutual engagement of the receiving body and the transmitting body.

It is preferable for the centering edge on the front of the receiving body to be substantially symmetrically curved, in particular having the shape of an arc of a circle, such as comprising the shape of at least a semicircle. As a result, it is guaranteed that the transmitting body may perform a motion of translation sideways, i.e. transversely to the direction of travel, for accurate alignment. In other words, the transmitting body is self aligning. Furthermore, the frictional forces are minimal while the receiving plate of the manure removing vehicle and the transmitting plate of the charging station are brought over and/or against each other to reach the charging state. There is also minimal risk of the receiving body of the manure removing vehicle remaining stuck on the transmitting body of the charging station when the manure removing vehicle travels back out of the charging station after wireless charging is completed.

In a preferred embodiment, the centering edge of the receiving body comprises a groove, wherein the transmitting body is provided with at least two centering bosses, which are configured to engage in the groove of the centering edge on either side of the central axis as the manure removing vehicle enters the charging station in the direction of travel, i.e. forward. In particular, the centering bosses have an undercut shape. The undercut shape prevents the transmitting body shooting past the receiving body and thus returning to the waiting state. When the manure removing vehicle enters the charging station, the groove of the centering edge is caught by the centering bosses of the transmitting body. As the manure removing vehicle then travels further forward into the charging station, the centering edge pushes the transmitting body out of the waiting state by means of the centering bosses, against the action of the pretension. The transmitting plate of the transmitting body is pulled toward the receiving plate of the manure removing vehicle, so that the transmitting plate ends up above and/or against the receiving plate. As a result, alignment in the direction perpendicular to the receiving and transmitting plates is particularly reliable.

In an embodiment the receiving body is arranged on an upper side of the manure removing vehicle and the flat surface of the receiving body faces upward, wherein the flat surface of the transmitting body of the charging station is downward facing and is located at a height that is adapted to the height of the upward facing flat surface of the receiving body of the manure removing vehicle in such a way that these flat surfaces can be brought over and/or on each other into the charging state. In this case the transmitting body of the charging station in the waiting state is suspended substantially freely movably on the charging station. Through engagement with the receiving body of the manure removing vehicle that enters the charging station, the transmitting body may end up above or on the receiving body so that electrical energy is transferable wirelessly from the primary coil of the transmitting body to the secondary coil of the receiving body. In this case the transmitting body in the waiting state is higher than the receiving body, and as the manure removing vehicle travels under the transmitting body through into the charging station, the receiving body entrains the transmitting body and the transmitting body can move from the front stop somewhat downward, onto the receiving body. The transmitting body "falls" as it were onto the receiving body and also remains thereon under its own weight. On the top of the manure removing vehicle, the receiving body is less liable to fouling with manure and the like, which may hamper alignment.

In a preferred embodiment, the manure removing vehicle comprises a water system for spraying water on the floor, said water system being provided with at least one water reservoir for receiving water, at least one spray head for spraying water on the floor, and a water feed connection for feeding water to the water system. The water feed connection, the water reservoir and the spray head of the water system are connected to each other by means of a pipe system. Moreover, the charging station comprises a water supply connection, which is couplable to the water feed connection of the water system for supplying water to the water system, to fill the water reservoir. After the primary coil of the transmitting body and the secondary coil of the receiving body have reached the charging state, the transmitting body of the charging station is movable further against the action of the pretension through engagement with the receiving body of the manure removing vehicle that travels further into the charging station in the direction of travel, i.e. forward, in such a way that the water feed connection of the manure removing vehicle is coupled automatically to the water supply connection of the charging station. Moreover, the control system of the manure removing vehicle is configured to, once the water reservoir is filled, have the manure removing vehicle travel in the charging station opposite to the direction of travel, i.e. backward, over a distance such that the water feed connection is decoupled automatically from the water supply connection while the primary coil of the transmitting body and the secondary coil of the receiving body remain aligned in the charging state. The distance is for example between 10 and 30 cm, such as about 15 cm.

In this case the water supply connection is installed in such a way that as the manure removing vehicle travels forward into the charging station, coupling of the water feed connection of the manure removing vehicle to the water supply connection takes place after the primary coil of the transmitting body and the secondary coil of the receiving body are mutually aligned in the charging state. In other words, first the manure removing vehicle travels into the charging station to align the primary coil of the transmitting body and the secondary coil of the receiving body in the charging state, then the manure removing vehicle travels further forward into the charging station, so that water coupling is brought about for supplying water to the water reservoir of the manure removing vehicle. Meanwhile the primary coil of the transmitting body and the secondary coil of the receiving body remain mutually aligned in the charging state.

Water coupling comprises for example a mechanically controllable valve device. Water coupling is automatic, i.e. during coupling of the water feed connection of the manure removing vehicle to the water supply connection of the charging station, the water coupling opens so that water is fed to the water reservoir of the manure removing vehicle. If the water feed connection of the manure removing vehicle is decoupled, i.e. the connection to the water supply connection of the charging station is broken, the water coupling shuts automatically. A water coupling of this kind has a low cost price, but is not always completely hermetic. In other words, leakage may occur during filling of the water reservoir. However, charging of the battery system takes much longer than filling of the water reservoir of the manure removing vehicle. If the water coupling were to remain in place for the complete charging time, there would therefore be a risk of water wastage. By making it possible for the water feed connection to be decoupled from the water supply connection while wireless charging is in progress, the risk of high water consumption through leakage is practically excluded. Alternatively, a high-quality water coupling could be chosen, which is almost leakproof, or a water coupling that is controllable with a switch for opening and closing the water coupling, but such alternatives are more expensive and comprise extra components that are susceptible to wear and faults.

The manure removing vehicle may be configured in various ways. In an embodiment, the manure removing vehicle comprises a manure slider or manure scraper for moving and/or scraping manure over the floor. During travel of the manure removing vehicle, the manure slider slides over the barn floor. The manure slider is in contact with the floor in order to move and/or scrape manure that is present thereon. With a solid barn floor, a quantity of manure is then accumulated or pushed up in front of the manure slider, i.e. a "manure bath" forms in front of the manure slider. The manure removing vehicle may comprise a manure feed device for in-feed of manure from the floor and moving of the fed-in manure to a manure storage container. For example, the manure accumulated in front of the manure slider is sucked up or picked up, such as raised by a rotary feed, and stored temporarily in the manure storage container. In other words, as it travels over the floor the manure removing vehicle collects manure from the floor into the manure storage container.

The manure removing vehicle may further comprise a manure discharge opening for discharging manure from the manure storage container, which in particular is arranged at the bottom of the manure storage container. It is possible for the manure discharge opening to be combined with the manure feed opening, i.e. the manure feed opening and the manure discharge opening are formed by one and the same opening, or for the manure discharge opening to be a separate, second opening, which for example is closable by a controllable discharge valve. Once the manure storage container is full, the manure feed device stops the in-feed of manure and the manure removing vehicle travels to a dump in order to empty the manure storage container. The dump comprises a dump opening, which opens into a manure reservoir.

The charging station may comprise the dump opening. In this case the charging station forms a dump at the same time, i.e. the battery system can be charged during dumping, which is efficient. Preferably, the dump opening is arranged in the floor for dumping manure from the manure discharge opening of the manure storage container through the dump opening to a manure reservoir or manure pit that extends under the floor. If the manure removing vehicle is located with the manure discharge opening above the dump opening, the manure is discharged from the manure storage container through the dump opening to the manure reservoir.

The charging station and/or the dump, each separately or combined, may also be placed outside the barn. Obviously it is also very well possible for the charging station and the dump to be separate from each other, i.e. the charging station is located at a distance from the dump. For example, the vehicle first travels to the dump to empty the manure storage container, and then from the dump to the charging station to charge the battery system. The dump may be located in the open air, while the charging station is for example installed in the barn.

It is also possible according to the invention for the manure removing vehicle to be configured for application with a grid floor or slatted floor, i.e. a floor with slots and a manure reservoir or manure pit under the barn floor for receiving manure that is moved through the slots by the scraping action of the manure removing vehicle. In other words, during travel of the manure removing vehicle the manure slider slides over the barn floor to push the manure through the slots, which then drops into the manure reservoir under the effect of gravity. In this way, the manure is removed from the grid floor.

The invention also relates, in combination, to a barn for keeping animals, such as dairy cows or cows for meat production, as well as a system as described above. In particular, the manure removing vehicle and the charging station are located in the barn, i.e. in the space for the keeping of animals. As already stated above, the charging station may, however, also be placed outside the barn.

The invention further relates to a method for removing manure and/or urine from a floor in a barn for keeping animals, such as dairy cows, cows for meat production, pigs or goats, wherein use is made of a system as described above, and wherein the method comprises:

• moving the autonomous manure removing vehicle over the barn floor to remove manure from the floor,

• moving the manure removing vehicle to the charging station,

• travelling or driving the manure removing vehicle into the charging station in the direction of travel, wherein the transmitting body of the charging station is moved from the waiting state against the action of the pretension, through engagement with the receiving body of the manure removing vehicle, in such a way that the primary coil of the transmitting body and the secondary coil of the receiving body are mutually aligned in the charging state, and

• wireless charging of the battery system of the manure removing vehicle in the charging station by wireless transfer of electrical energy from the primary coil of the transmitting body of the charging station to the secondary coil of the receiving body of the vehicle.

If the manure removing vehicle is configured with a manure storage container for temporary collection of manure that is removed from the floor, and the manure removing vehicle travels to the dump in order to empty the manure storage container when it gets full, the battery system is in particular charged during and/or after dumping the manure.

The method according to the invention has the same technical effects and advantages as described above in relation to the system according to the invention.

The invention will now be explained in more detail with reference to the appended figures.

Figure 1 shows a schematic top view of a barn with a system according to the invention, wherein the system is provided with an autonomous manure removing vehicle and a charging station that forms a dump.

Figure 2 shows a perspective view of the manure removing vehicle in the charging station of the system shown in Figure 1.

Figure 3 shows a partially cut-away side view of the manure removing vehicle shown in Figure 2 in the charging station.

Figure 4 shows a top view of the manure removing vehicle shown in Figure 3 in the charging station.

Figures 5A-5E show top views of various steps in aligning a receiving body of the manure removing vehicle relative to a transmitting body of the charging station for the system shown in Figures 1-4.

Figures 6A-6G show side views of various steps in aligning a primary coil of a transmitting body of the charging station relative to a secondary coil of a receiving body of the manure removing vehicle for the system shown in Figures 1-4, wherein the charging station is partially cut away.

Figure 7 shows an enlarged perspective view of the receiving body of the manure removing vehicle of the system according to Figures 1-6.

Figures 8 and 9 show perspective views of the charging station of the system according to Figures 1-6, wherein Figure 9 is partially cut away.

Figure 1 shows a system 1 for the removing of manure and/or urine from a solid floor 2 in a barn 3 that is configured as a typical loose housing barn for cows with cubicles 5. On the floor 2 there is manure and urine from the animals 4, and for example also straw, sand and/or sawdust, with which the cubicles 5 are lined. In this exemplary embodiment the system 1 comprises an autonomous manure removing vehicle 6 for removing manure. The manure removing vehicle 6 is located on the floor 2 among the animals 4. The manure removing vehicle 6 is supported on the floor 2 by means of two wheels 7 and a manure slider 8 (see Figures 3 and 4). The manure removing vehicle 6 may, however, also be supported in some other way, for example with a front wheel or a supporting element, such as a sliding block.

The manure slider 8 is configured for moving and/or scraping manure over the floor 2. During travel of the manure removing vehicle 6 over the floor 2, the manure slider 8 is in contact with the floor 2 in order to move and/or scrape manure that is present thereon. The manure slider 8 has for example a flexible bottom edge that scrapes over the floor 2. With the solid barn floor 2, a quantity of manure is then accumulated or pushed up in front of the manure slider 8, i.e. a "manure bath" forms in front of the manure slider 8. In this exemplary embodiment the manure slider 8 forms part of a manure feed device for feeding or introducing manure from the floor 2 and moving the fed-in manure to a manure storage container 16 (see Figure 3), which defines an interior, in which manure can be collected temporarily.

The manure removing vehicle 6 is unmanned and self-propelled. The manure removing vehicle 6 can find its way autonomously by means of an electronic control system 9 (see Figure 4) with sensors, such as an ultrasonic sensor and a gyroscope. On the basis of the signals detected by the sensors, the control system 9 controls a drive system with electric drive motors 10 for the wheels 7 of the manure removing vehicle 6. Because the wheels 7 are controllable independently of each other, the manure removing vehicle 6 can be steered and can travel a desired route through the barn 3.

The drive system and the control system 9 are supplied by a battery system 11 for storing electrical energy on board the manure removing vehicle 6. The battery system 11 comprises one or more rechargeable batteries, in particular 24V lithium batteries. The battery system 11 and electronic components of the control system 9, which are not resistant to manure or urine, are enclosed in a housing 12 of the manure removing vehicle 6. The housing 12 forms an electrical enclosure for housing electrical and/or electronic components of the manure removing vehicle 6.

In this exemplary embodiment this housing 12 is fitted substantially above and in front of the manure slider 8. The housing 12 comprises an access opening 14 at the top, for example for maintenance work. The access opening 14 is closable by a hinged cover 15. The cover 15 is movable between a closed state, in which the access opening 14 is closed by the cover 15, and an open state, in which the interior of the housing 12 is accessible via the access opening 14.

The manure storage container 16 is located behind the housing 12. The manure storage container 16 comprises a bottom 17, which slants toward a manure feed and discharge opening 18, which is arranged at a lowest level of the bottom 17. The interior of the manure storage container 16 is further delimited by the inside of the two side walls 19 of the manure removing vehicle 6. In each side wall 19 there is a wheel housing for receiving a wheel 7 and the associated electric drive motor 10 (see Figures 2 and 4).

Although in this exemplary embodiment the manure storage container 16 has a single manure feed and discharge opening 18, i.e. manure taken up from the floor 2 is fed via this opening 18 to the manure storage container 16 and during emptying of the manure storage container 16 the collected manure leaves the manure storage container 16 via the same opening 18, it is also possible for the manure removing vehicle 6 to have two separate openings: a first opening for supply of manure and a second opening for discharge of manure.

During travel, manure collects on the floor 2 in front of the manure slider 8, which extends partially around the manure feed opening and outlet 18. A "manure bath" is formed in front of the manure slider 8. In this exemplary embodiment the manure feed device comprises a vacuum pump in order to generate a partial vacuum in the interior of the manure storage container 16, so that manure in the manure bath is sucked up from the floor 2 and flows via the manure feed and discharge opening 18 to the interior of the manure storage container 16. The manure is stored therein until the manure storage container 16 gets substantially full.

A manure feed device for sucking up manure is described in detail in WO 2013/010785 A1, the contents of which are incorporated by reference in the present description, and will not be explained further. It should be noted that the manure feed device may also have some other configuration. Instead of sucking up manure as described above, the manure feed device may for example comprise a mechanical pick up mechanism for picking up or scooping up manure from the floor 2. Then the manure is for example moved upward by means of a rotor, and then ends up inside the manure storage container via a manure feed opening.

If the manure storage container 16 is full, the manure feed device stops the in-feed of manure and the manure removing vehicle 6 travels to a dump 20 in order to empty the manure storage container 8. At the dump 20, a dump opening 21 is installed in the floor 2, which opens into a manure reservoir or manure pit 22, which extends underneath the floor 2. If the manure removing vehicle 6 with the manure feed and discharge opening 18 is positioned above the dump opening 21 (see Figure 3), the control system 9 switches off the vacuum pump, so that the partial vacuum in the interior of the manure storage container 16 disappears and the manure flows under the effect of gravity from the manure storage container 16, through the dump opening 21, and into the manure reservoir 22.

The discharge of the manure may, however, also have some other configuration. In the case of a manure removing vehicle that picks up manure and brings it via a rotor upward to the manure storage container, for example a separate manure discharge opening is provided, which is closable by a controllable discharge valve. At the dump, the discharge valve for example swivels away to open the manure discharge opening, so that the manure drops from the manure storage container into the manure reservoir.

Although the manure removing vehicle 6 described above is configured for receiving the manure and moving the received manure to a dump 20, the autonomous manure removing vehicle may, however, also be configured for moving and/or scraping manure through slot-shaped openings of a "grid floor" or “slatted floor” of the barn (not shown). In other words, in this case, during travel of the manure removing vehicle the manure slider scrapes over a grid floor of the barn to push the manure through the slots, which then drops into the manure reservoir under the floor under the effect of gravity.

The system 1 according to the invention further comprises a charging station 23 for wireless charging of the battery system 11 of the manure removing vehicle 6. If it is desired to charge the battery system 11, the manure removing vehicle 6 travels to the charging station 23. The charging station 23 defines a charging position for the manure removing vehicle 6 during charging of the battery system 11.

In this exemplary embodiment the charging station 23 comprises the dump opening 21, i.e. the charging station 23 and the dump 20 are integrated in this case. During discharge of the manure, the battery system 11 of the manure removing vehicle 6 can be charged. Obviously it is also possible that the charging station 23 does not form a dump. Also, the charging station 23 and/or the dump 20, each separately or combined, may be placed outside the barn 3.

As shown in Figures 8 and 9, the charging station 23 comprises a transmitting body 24, which is provided with a transmitting plate 24a with a primary coil 25 (shown schematically in Figure 8). The transmitting plate 24a is mounted adjacent to a downward facing flat surface of the transmitting body 24. The flat surface of the transmitting body 24 of the charging station 23, viewed in a direction opposite to the forward direction of travel y as the manure removing vehicle 6 enters the charging station 23, extends slanting upward relative to the horizontal.

The manure removing vehicle 6 comprises a receiving body 26, which is provided with a receiving plate 26a with a secondary coil 27 (shown schematically in Figure 7). The receiving plate 26a is applied adjacent to an upward facing flat surface of the receiving body 26. The flat surface of the receiving body 26 of the manure removing vehicle 6, viewed in the forward direction of travel y toward the charging station 23, extends slanting downward relative to the horizontal.

The transmitting plate 24a and the receiving plate 26a are each formed by a round disk ("charging pad"), in this exemplary embodiment with a diameter of about 16 cm and a thickness of about 2 cm. The charging pads 24a, 26a are incorporated in the transmitting body 24 and the receiving body 26. The charging pads 24a, 26a comprise the primary coil 25 or the secondary coil 27, respectively. The primary and secondary coils 25, 27 may each comprise one or more induction coils, for example a stack of induction coils.

The receiving body 26 is fastened rigidly to an upper side 13 of the manure removing vehicle 6. The upper side 13 of the manure removing vehicle 6 is defined by a substantially flattened upper surface. The receiving body 26 lies along said upper surface. At this location, the receiving body 26 is less liable to fouling and corrosion, and the risk of damage through trampling by cows is also minimal.

In this exemplary embodiment, the flattened upper surface has a somewhat rounded or round shape, but the upper surface may also define a substantially horizontal plane (not shown). The upper surface forms a portion of an outermost wall, i.e. the outer contour of the manure removing vehicle 6. The upper surface determines the height of the manure removing vehicle 6, which in this exemplary embodiment is about 60 cm.

As shown in Figure 7, in this exemplary embodiment the receiving body 26 is mounted on the cover 15, which defines a portion of the flattened upper surface. Viewed in the vertical direction, the receiving body 26 is located directly above the interior of the housing 12. As a result, a short connection to the control system 9 and the battery system 11 is possible, while said connection in addition runs exclusively in a region that is closed off from fouling by manure, urine and the like.

The receiving body 26 is, moreover, placed in a vertical central longitudinal plane A of the manure removing vehicle 6 (see Figure 4). The vertical central longitudinal plane A lies centrally between the side walls 19 of the manure removing vehicle 6. In other words, the receiving body 26 is placed at the top of the manure removing vehicle 6 centrally between the side walls 19. Viewed in a direction transverse to the straight forward direction of travel y of the manure removing vehicle 6, the receiving body 26 is located in the middle of the manure removing vehicle 6.

If animals 4 relieve themselves on the upper side 13 of the manure removing vehicle 6, manure may remain thereon. In practice this manure collects in particular in elongated strips on the upper side 13 adjacent to the side walls 19. In the middle, the upper side 13 of the manure removing vehicle 6 is less fouled with manure. Consequently, the receiving body 26 in the middle of the manure removing vehicle 6 has relatively little exposure to fouling and corrosion by manure.

In order to charge the battery system 11 wirelessly, the primary coil 25 of the transmitting body 24 and the secondary coil 27 of the receiving body 26 are mutually aligned in a charging state, in which electrical energy is transferable wirelessly from the primary coil 25 to the secondary coil 27. The height of the downward facing flat surface of the transmitting body 24 is adapted to the height of the upward facing flat surface of the receiving body 26 of the manure removing vehicle 6 in such a way that these flat surfaces can be brought over and/or on each other in the charging state.

The transmitting plate 24a and the receiving plate 26a lie on top of one another in the charging state. For reliable and efficient wireless energy transfer it is desirable to position the primary coil 25 of the transmitting body 24 close to the secondary coil 27 of the receiving body 26, in particular at a distance apart of for example max. 1 or 2 cm. Alignment is shown in steps in Figures 5A-5D and 6A-6F, while Figures 7-9 illustrate further details of the receiving body 26 and the transmitting body 24.

In order to align the flat surfaces of the transmitting body 24 and the receiving body 26 reliably on top of each other, first the receiving body 26 is cleaned in order to remove most of the manure and other fouling thereon. After all, during use, the receiving body 26 of the manure removing vehicle 6 becomes (very) fouled with manure from the animals 4, often also in combination with urine, straw, sand and/or sawdust, which lie on the floor 2. After a time the manure becomes hard ("caked"). There may also be pieces or lumps in the manure. In consequence, the receiving body 26 is usually covered with a layer of manure when the manure removing vehicle 6 enters the charging station 23.

This manure renders it more difficult to arrange the flat surfaces of the transmitting body 24 and receiving body 26 on top of each other. In order to align the primary coil 25 of the transmitting body 24 and the secondary coil 27 of the receiving body 26 mutually in the charging state, in which electrical energy is transferable wirelessly from the primary coil 25 to the secondary coil 27 for wireless charging of the battery system 11, the charging station 23 comprises a cleaning device 42 for removing manure, urine and the like from the receiving body 26 while the manure removing vehicle 6 enters the charging station 23 and before the primary coil 24a of the transmitting body 24 and the secondary coil 26a of the receiving body 26 are mutually aligned in the charging state (see Figures 6A, 6B and 8).

Although the receiving body 26 does not have to be completely clean, the cleaning device 42 removes the fouling by manure and the like to a sufficient degree from the receiving body 26 to make it possible for the primary coil 25 of the transmitting body 24 and the secondary coil 27 of the receiving body 26 to be mutually aligned in the charging state. After cleaning by the cleaning device 42, manure or other fouling no longer impedes alignment in the charging state. Moreover, owing to the cleaning device 42, the manure removing vehicle 6 entrains considerably less manure into the charging station 23, so that the transmitting body 24 of the charging station 23 also becomes fouled less quickly.

The cleaning device 42 comprises a scraping element 43 for scraping manure from the flat surface of the receiving body 26 while the manure removing vehicle 6 travels forward in the direction of travel y into the charging station 23. The scraping element 43 is made of a flexible plastic, which in this exemplary embodiment comprises polyurethane. The scraping element 43 comprises, on the underside thereof, a scraping edge 44, which comes into contact with the flat surface of the receiving body 26 when the manure removing vehicle 6 travels under the scraping element 43 and into the charging station 23. The scraping edge 44 forms a substantially horizontal, straight bottom edge, which extends substantially transversely relative to the direction of travel y of the manure removing vehicle 6.

As the scraping edge 44 moves over the flat surface of the receiving body 26 to remove manure, elastic deformation of the scraping edge 44 occurs. During contact with the flat surface of the receiving body 26, the scraping edge 44 is bent, so that during scraping, the scraping edge 44 exerts a compressive force on the receiving body 26. Manure is removed while the bent scraping edge 44 of the scraping element 43 moves over the flat surface of the receiving body 26. When the manure removing vehicle 6 is driven away from the charging station 23 and the scraping edge 44 no longer makes contact, the scraping element 43 bends back to the original shape as shown in Figure 8.

Optionally, the cleaning device 42 comprises a water device for application of water on the receiving body 26, which for example is configured as a water nozzle (not shown). The water nozzle sprays water on the flat surface of the receiving body 26 before the scraping element 43 scrapes over this flat surface to remove manure. By supplying water to manure that is present as fouling on the flat surface of the receiving body 26, the scraping element 43 can remove this manure more easily and more effectively.

Only after the flat surface of the receiving body 26 has been cleaned and the manure removing vehicle 6 has then driven further into the charging station (see Figures 5B and 6C), the receiving body 26 of the manure removing vehicle 6 engages on the transmitting body 24 of the charging station 23, which is in a waiting state or initial state. The receiving body 26 of the manure removing vehicle 6 then comes into contact with the transmitting body 24 of the charging station 23.

The transmitting body 24 is pretensioned to the waiting state by means of a spring 33. As shown in Figures 8 and 9, the transmitting body 24 is fastened to a slide 28 of the charging station 23, which is suspended movably on a carrying bar 32 at a height above the floor 2. In this exemplary embodiment, the slide 28 comprises a carrying bracket 29 and a supporting plate 30 with an opening 31. The carrying bar 32 passes with clearance through the opening 31, under the carrying bracket 29, and is received with clearance in an opening 35 of a carrying frame 34 of the charging station 23. As a consequence of this clearance in the opening 35 of the carrying frame 34, the carrying bar 32 is somewhat tiltable relative to the carrying frame 34.

On either side of the carrying bar 32, the slide 28 comprises in each case a bush 36. The bushes 36 are receivable in receiving jaws 37, which are fastened to the carrying frame 34. The receiving jaws 37 form a front stop for the slide 28 with the transmitting body 24 fastened thereon. The front stop determines a front position for the transmitting body 24. During alignment, the slide 28 is movable over a distance backwards to a rearmost position, which is defined in that the manure removing vehicle 6 cannot travel further than until a bumper 45 on the front of the manure removing vehicle 6 comes into contact with a stop of the charging station 23, which in this exemplary embodiment is formed by two buffers 46 (see Figures 6F and 8).

The spring 33 is pushed onto the carrying bar 32 and is pretensioned between the supporting plate 30 and the carrying frame 34, so that the bushes 36 of the slide 28 are received in the receiving jaws 37 with a pretensioning force. The transmitting body 24 is then in the waiting state. The transmitting body 24 consequently always returns to the same accurately defined position when the manure removing vehicle 6 has left the charging station 23. As a result, during alignment the transmitting body 24 always begins at the same position that corresponds to the waiting state.

The transmitting body 24 is substantially freely movable from the waiting state, against the action of the spring 33. "Freely movable" is understood to mean that the transmitting body 24, on moving from the front position, which is determined by the front stop formed by the receiving jaws 37, to the rearmost position, which is determined by contact of the manure removing vehicle 6 against the buffers 46, is movable relative to the carrying frame 34 of the charging station 23 to adjust the position and orientation of the transmitting body 24 to the receiving body 26 of the manure removing vehicle 6 while the manure removing vehicle 6 enters the charging station 23 and the receiving body 26 engages on the transmitting body 24.

The transmitting body 24 may perform a motion of translation in the direction of travel y, so that the bushes 36 are released from the receiving jaws 37. The transmitting body 24 may also perform a motion of translation in a direction transverse to the direction of travel y, i.e. to the left and right. Furthermore, the transmitting body 24 may swivel to the left and right about a substantially vertical swivel axis through displacement of the carrying bracket 29 over the carrying bar 32, and rotate slightly to the left and right about the carrying bar 32.

The transmitting body 24 further comprises two centering bosses 38, which are arranged on either side of the carrying bar 32. The centering bosses 38 are located in angular regions to the left and right of the transmitting body 24, so that the flat surface that is contiguous with the transmitting plate 24a remains free, i.e. the flat surface of the receiving body 26 can be applied thereto. The centering bosses 38 have an undercut shape. The undercut shape prevents the transmitting body 24 going beyond the receiving body 26 while the manure removing vehicle 6 travels forward into the charging station 23 in the direction of travel y.

As shown in Figure 7, the receiving body 26 comprises, on a front side thereof, a centering edge 40, which projects upward, substantially transversely from the cover 15 of the manure removing vehicle 6. The centering edge 40 forms a vertical collar, which partially surrounds the receiving plate 26a. Viewed in a direction opposite to the forward direction of travel y, i.e. backward from the front of the manure removing vehicle 6, the centering edge 40 on either side of the central axis of the receiving plate 26a runs away in an outward direction. In this exemplary embodiment the centering edge 40 has roughly the shape of a semicircle at the front of the receiving body 26. As a result, the centering edge 40 is self-aligning. The centering edge 40 further comprises a groove 41 , which is configured to interact with the undercut centering bosses 38 of the transmitting body 24.

The height of the groove 41 of the centering edge 40 of the receiving body 26 and the height of the centering bosses 38 of the transmitting body 24 are matched to each other, i.e. as the manure removing vehicle 6 enters the charging station 23, the centering edge 40 first comes into contact with at least one of the centering bosses 38 of the transmitting body 36 in the waiting state. The undercut shape of this centering boss 38 is received in the groove 41 , so that the transmitting body 24 does not shoot back over the receiving body 26 to the waiting state (see Figures 5B and 6C). With further travel of the manure removing vehicle 6, the other centering boss 38 also engages in the groove 41 (see Figure 5C). In other words, the groove 41 of the centering edge 40 is caught by the centering bosses 38 of the transmitting body 24. The centering bosses 38 then engage in the groove 41 of the centering edge 40 on either side of the central axis of the receiving plate 26a. Because the centering edge 40 is of semicircular shape, the transmitting body 24 is self-aligning, i.e. the transmitting body 24 performs a motion of translation sideways, i.e. transversely to the direction of travel y, for accurate alignment.

By means of the centering bosses 38, the centering edge 40 forces the transmitting body 24 out of the waiting state, against the action of the pretension. The bushes 36 then move from the receiving jaws 37 and down over tracks or paths 39, while the carrying bar 32 tilts slightly downward relative to the opening 35 in the carrying frame 34 (see Figure 6D). As a result, the flat surface of the transmitting body 24 also tilts against the flat surface of the receiving body 26, so that the transmitting plate 24a and the receiving plate 26a end up being substantially parallel to each other. The manure removing vehicle 6 is thereby maneuvered under the transmitting body 24 of the charging station 23 in such a way that the primary coil 25 of the transmitting body 24 is aligned in the charging state above the secondary coil 27 of the receiving body 26.

Since the transmitting body 24 is moved against the action of the pretension, the flat surfaces of the transmitting body 24 and receiving body 26 are pressed against each other in the charging state. Also owing to the weight of the slide 28 with the transmitting body 24, the flat surface of the transmitting body 24 "falls" firmly against the flat surface of the receiving body 26.

If the manure removing vehicle 6 travels further after reaching the charging state, the flat surfaces of the transmitting body 24 and the receiving body 26 remain lying on each other, while the slide 28 with the transmitting body 24 slides further over the carrying bar 32 in the direction of travel y. The bushes 36 then become free from the tracks 39 (see Figure 6E). As mentioned above, the manure removing vehicle 6 may continue its travel until the bumper 45 at the front thereof comes into contact with the two buffers 46 of the carrying frame 34 of the charging station 23 (see Figures 6F and 8).

The manure removing vehicle 6 further comprises a water system 50, which is configured for spraying water on the floor 2 (shown schematically in Figure 3). It is beneficial to wet the floor 2 to promote removal of manure from the floor 2. The water system 50 is optional. As can be seen in Figure 4, in this exemplary embodiment the water system 50 comprises a water feed connection 51 for feeding water to the water system 50. The water feed connection 51 is couplable to a water supply connection 52, which is located at the charging station 23. The water supply connection 52 is for example connected to a water main 53 or a water buffer tank (not shown).

The water feed connection 51 of the manure removing vehicle 6 is connected by means of a pipe system 54 to two water reservoirs 55 for receiving water. In this exemplary embodiment the water reservoirs 55 are formed as flexible water bags, as is also described in WO 2017/069615 A1. In Figure 3 the water bags 55 are not filled with water and so are substantially flat. When the water bags 55 are filled with water, the volume of the water bags 55 increases. Obviously it is possible to use just one water reservoir, and the water reservoir may be configured differently, for example as a plastic or metal tank (not shown).

By means of the pipe system 54, the water reservoirs 55 are further connected to one or more spray heads for spraying water on the floor 2 (not shown). For example, a spray head of the water system 50 is fitted on a front side of the manure removing vehicle 6, wherein this spray head sprays water on the floor 2 in front of the manure removing vehicle 6 while the manure removing vehicle 6 travels forward. In other words, this spray head always sprays water on an area of the floor 2 onto which the manure removing vehicle 6 travels. Furthermore, the water system 50 may comprise a further spray head, which for example is configured to spray water on the area of the floor 2 behind the manure removing vehicle 6. The water supply connection 52 is omitted in Figures 5A-5C and 6A-6E, but is shown in Figures 5D, 5E, 6F and 6G, which show the manure removing vehicle 6 during charging of the battery system 11 during and after filling of the water reservoirs 55. The water supply connection 52 of the charging station 23 and the water feed connection 51 of the manure removing vehicle 6 are coupled automatically to supply water to the water system 50 when the manure removing vehicle 6 enters the charging station 23. On coupling of the water feed connection 51 of the manure removing vehicle 6 to the water supply connection 52 of the charging station 23, the water coupling opens automatically so that water is fed to the water reservoirs 55 of the manure removing vehicle 6. The water coupling comprises for example a mechanically controllable valve device (not shown). While the manure removing vehicle 6 is being charged in the charging station 23, the water system 50 can be filled with water.

The water supply connection 52 is installed in such a way that as the manure removing vehicle 6 travels forward into the charging station 23, water coupling only takes place after the primary coil 25 of the transmitting body 24 and the secondary coil 27 of the receiving body 26 are mutually aligned in the charging state. In other words, as the manure removing vehicle 6 enters the charging station 23, first the charging state is reached, and then the manure removing vehicle 6 continues to travel forward into the charging station 23, so that water coupling takes place automatically for supplying water to the water reservoirs 55. The charging state is maintained, even if the manure removing vehicle 6 abuts against the buffers 46 (see Figure 5D and 6F).

Water is supplied for as long as the coupling between the water feed connection 51 of the manure removing vehicle 6 and the water supply connection 52 is maintained. After the water reservoirs 55 have been substantially completely filled with water, the water feed connection 51 of the manure removing vehicle 6 is decoupled by travelling back a small distance, for example about 10-15 cm, within the charging station 23. The connection to the water supply connection 52 of the charging station 23 is then broken, so that the water coupling closes automatically. The charging state is maintained during the backward travel of the manure removing vehicle 6 (see Figures 5E and 6G).

Charging of the battery system 11 takes much longer than filling of the water reservoirs 55. If the water coupling were to be maintained for the complete charging time, there would be a risk of water wastage through leakage. By making it possible for the water feed connection 51 to be decoupled from the water supply connection 52 while wireless charging is in progress, the risk of high water consumption through leakage is practically excluded. After the control system 9 has detected that the battery system 11 is charged sufficiently, the manure removing vehicle 6 travels out of the charging station 23. In this exemplary embodiment the manure removing vehicle 6 first moves back further, and then turns sideways away from the charging station 23. When the manure removing vehicle 6 has left the charging station 23, the transmitting body 24 is returned to the waiting state as a result of the pretension of the spring 33. The transmitting body 24 is then relocated in this waiting state in the same accurately defined position. Whenever the battery system 11 of the manure removing vehicle 6 (or of a second or further manure removing vehicle) has to be charged, alignment can take place reliably. The invention is not limited to the exemplary embodiment shown in the figures. A person skilled in the art can make various adjustments that are within the scope of the invention. In particular the manure feed device of the manure removing vehicle may be configured differently. Instead of sucking up manure as described above, the manure feed device may comprise a mechanical scooping mechanism for scooping up manure from the floor. It is also possible for the manure removing vehicle to comprise two separate openings for feed or discharge of manure, respectively, i.e. a manure feed opening and a manure discharge opening. The manure is then for example moved upward by means of a rotary feed, and goes via the manure feed opening into the interior of the manure storage container. The manure can be discharged via the manure discharge opening. With a manure removing vehicle of this kind, a water system may also optionally be used for wetting the floor as described above.