TRACTOR

Description

[0001] The invention relates to an agricultural tractor having a frame which connects a front tractor part and a rear tractor part to one another via a connecting element, a driver's seat in the region of the rear tractor part, a drive and at least four wheels, wherein the connecting element of the frame which connects the rear tractor part and the front tractor part to one another is arranged at least 60 cm above the driver's seat and extends substantially horizontally to the front tractor part.

[0002] Today, agricultural tractors are predominantly powered by diesel engines. Heavy tractors weighing over 5 tons are predominantly used in arable farming. Their job is to pull large and heavy agricultural machinery. For the cultivation of low-growing plants arranged in rows, such as in vegetable gardens or tree nurseries, smaller tractors weighing only between 1.5 and 3 tons are used. Since these plants are planted in rows with spaces between them, the lower weight of the tractor reduces unwanted soil compaction between the shorter rows.

[0003] To prevent weeds or grass growth between rows, pesticide spraying can be used. Hoes or hoe brushes (see https: / / www.baertschi.com / de / fobro-schar- und-sternhackgerate / ) can also be used to mechanically remove weeds between rows or damage their roots so that they can no longer grow and thus compete with the crop for nutrients from the soil. This mechanical tillage is primarily used in organic vegetable cultivation.

[0004] A special vehicle that fulfills this task is the Fobro-Mobil (https: / / fobro-mobil.ch / de / fobromobil-d49 / ). This vehicle is powered by a diesel or gasoline engine. The Fobro-Mobil has three attachments for implements, such as cultivators or hoeing brushes. These implements can be attached at the rear of the tractor, at the front of the tractor, and in the middle of the tractor, directly in front of the driver's seat. For this purpose, the front and rear axles are connected above the driver's head with two pipes. This allows the driver to see the cultivator attached in the middle attachment directly in front of them and to steer it precisely between the rows without damaging the crop. Normal tractors do not have a middle attachment and must attach them to the rear of the tractor. This usually requires an additional employee to sit on the cultivator and steer it between the rows so that the plants are not damaged. This is time-consuming and expensive.

[0005] The driver of the Fobro-Mobil sits next to the diesel or petrol engine, offset from the center. This has the advantage that the weight on the rear axle is evenly distributed across both wheels, ensuring good propulsion and even pressure on the ground. In the direction of travel of the Forbo-Mobil, for example, the driver's weight is closer to the rear left wheel and the weight of the engine is closer to the rear right wheel. The front and rear wheels of the Fobro-Mobil are connected by two tubes or profiles, which has the disadvantage that when driving on the road, the driver sees a connecting tube directly in front of them, which obscures their view straight ahead. The second tube or profile, to the right of it in the direction of travel, obscures their view to the right of the roadside, which can be dangerous for pedestrians and makes it difficult to judge the distance to the roadside.

[0006] Another vehicle that can fulfill this task is the Mastertrac (http: / / www.rath-maschinen.com / de / mastertrac.html). This vehicle is also powered by a diesel engine and has three attachment mounts: one at the rear, one at the front, and one in the middle of the vehicle, directly in front of the driver. The rear pair of wheels is also connected to the front pair of wheels, but with a curved profile next to the driver, or more precisely between the side-mounted engine and the driver's seat. The driver's head is roughly at the same height as this wheel connection. The driver's view of the hoe, mounted in the middle section, is obstructed by the wheel connection being centrally located at head height. Visibility in traffic is also obstructed by the positioning of this axle connection to the side of the road. Another disadvantage of this tractor is the lack of clearance between the bottom edge of the axle connection and the ground. This prevents large implements from being lifted sufficiently, which is a disadvantage when transporting over uneven terrain.

[0007] Such specialized tractors for tilling row crops are delivered without cabs, as these would otherwise obstruct the view of the hoeing tools and add weight. With these specialized tractors for tilling low-growing row crops, it is important to eliminate any unnecessary weight to avoid increasing soil pressure.

[0008] These specialty tractors, with three attachments for soil tillage equipment, are all powered by diesel or gasoline engines. With increasingly stringent environmental regulations and the reduction of CO2 emissions, it is becoming increasingly expensive to find suitable engines equipped with suitable exhaust aftertreatment systems to reduce CO2 and particulate matter emissions to legal requirements.

[0009] Another concern is the driver's health. The driver typically spends several hours working the soil on the specialty tractor. They sit directly next to the diesel or gasoline engine. Because these vehicles are designed without a cab, the driver is highly exposed to harmful exhaust emissions. Due to their proximity to the engine, the driver is also unprotected from the loud engine noise. As a result, they are usually forced to wear ear protection.

[0010] DE 10 55 377 A discloses a tractor for agriculture having a frame which connects a front tractor part and a rear tractor part via a connecting element, has a driver's seat in the area of ​​the rear tractor part, a drive and at least four wheels, wherein the connecting element extends horizontally to the front tractor part.

[0011] The object of the invention is to create a tractor for agriculture that avoids the above-mentioned disadvantages.

[0012] This object is achieved according to the invention by a tractor for agriculture having the features of claim 1.

[0013] In the special tractor according to the invention, the front tractor section and the rear tractor section are connected by a single connecting element, preferably consisting of a profile or tube or several closely spaced profiles or tubes. This connecting element, which connects the front tractor section and the rear tractor section, is mounted in such a way that the driver has a clear view to the right below the connecting element in the direction of travel. For this purpose, the distance from the height of the driver's seat, measured vertically upwards from the front edge of the seat, to the height of the lower edge of the connecting element must be at least 60 cm. The connecting element extends essentially horizontally to the front tractor section (which means that it can also slope slightly towards the front tractor section) and there merges into a vertical element from which the front wheels are suspended.The connecting piece is thus positioned above the driver's field of vision. The driver can then look to the right below the connecting element and also to an implement positioned behind the front of the tractor. This enables precise maneuvering when tilling rows of plants.

[0014] The connecting element is mounted centrally on the longitudinal axis of the special tractor so that the driver has a clear view to the front and to the side of an implement mounted in the middle of the tractor and has an unobstructed view straight ahead and to the side of the road when driving on the road.

[0015] A further development of the invention consists in that the connecting element of the frame, which connects the rear and the front part of the tractor, is arranged at least 70 cm, preferably at least 80 cm, above the driver's seat.

[0016] Thus, the connecting element is preferably mounted centrally on the longitudinal axis of the special tractor so that the driver has a clear view to the front and to the side of an implement mounted in the middle of the tractor and has an unobstructed view straight ahead and to the side of the road when driving on the road.

[0017] This prevents the driver's field of vision to the front from being restricted by the connecting element.

[0018] An advantageous embodiment of the invention is that the wheels are individually suspended and individually driven.

[0019] Alternatively, it is also possible for pairs of rear wheels or front wheels to be connected via one axle each and to be driven jointly via the connecting axle.

[0020] Two wheels or all four wheels can be driven.

[0021] A preferred embodiment of the invention is that at least one electric motor is provided as the drive.

[0022] In this context, it is preferred that the electric motor acts on the rear wheels.

[0023] However, it is also possible to provide all-wheel drive.

[0024] A preferred embodiment is explained in more detail below with reference to drawings.

[0025] It shows Fig. 1 a perspective view of a tractor according to the invention, Fig. 2 a side view of the tractor according to the invention, Fig. 3 the section AA to Fig. 2 , Fig. 4 a front view of the tractor according to the invention, Fig. 5 the section BB to Fig. 4 , Fig. 6 a plan view of the tractor according to the invention.

[0026] The agricultural tractor according to the invention comprises a frame 1 that connects a front tractor section 3 and a rear tractor section 4 via a connecting element 2. A driver's seat 5 and a drive 6 are provided in the rear tractor section 4. The tractor has at least four wheels 7a, 7b, preferably a pair of front wheels 7a and a pair of rear wheels 7b that are aligned with each other. The wheels 7a, 7b can be individually suspended or connected in pairs via an axle.

[0027] The connecting element 2 of the frame 1, which connects the rear tractor part 4 and the front tractor part 3, is arranged at least 60 cm, preferably at least 70 cm and particularly preferably at least 80 cm above the driver's seat 5 (height H in Fig. 4) and extends essentially horizontally to the front part of the tractor 3. In the present example, the essentially horizontal connecting element is designed to slope slightly forward. The underside of the connecting element 2 at the level of the front wheels 7a can be arranged up to 20% lower than the highest point of the underside of the connecting element 2. The connecting element 2 is arranged centrally between the rear wheels 7b and preferably also centrally between the front wheels 7a.

[0028] In the embodiment shown, the driver's seat 5 is arranged to the left of the connecting element 2 so as not to obstruct the driver's view to the front.

[0029] This type of arrangement of the connecting element 2 allows the driver to keep an eye on the implement arranged behind the front part of the tractor 3 while working in the field and also to have a clear view when driving on the road.

[0030] Either only the rear wheels 7b can be driven or there can be all-wheel drive.

[0031] Instead of a diesel or gasoline engine, one or more electric motors are preferably used to power the drive, hydraulics, and attached equipment. This avoids harmful exhaust emissions for the environment and the driver, as well as noise pollution for the driver. For this purpose, an electric-drive tractor according to the invention can be used in greenhouses. A further advantage of using an electric motor is the use of solar, wind, or biogas energy, which can be produced on-site by the user. This can significantly reduce the operating costs of the electric tractor.

[0032] The electric motor(s) can drive the vehicle directly by acting directly on the axles or wheels 7a, 7b, or the electric motor supplies power to a hydraulic circuit that drives the vehicle indirectly via the hydraulic system. The attached implements can also be driven directly by the electric motor(s) or supplied with power indirectly via hydraulic motors and hydraulic pumps. For this purpose, the tractor according to the invention has one or more hydraulic motors, one or more hydraulic pumps, and one or more hydraulic oil circuits.

[0033] The electric motor(s) used have a total power of at least 25 kW, preferably at least 30 kW, and most preferably at least 35 kW. Each electric motor has a voltage of at least 100 volts, preferably at least 360 volts. They are air-cooled or, preferably, water-cooled.

[0034] The electric tractor according to the invention has one or more batteries, together with a total output of preferably at least 25 kW, preferably at least 30 kW, and most preferably at least 35 kW. One or more batteries can either be permanently installed or provided as replacement batteries, so that the user of the tractor according to the invention can extend the operating time by exchanging pre-charged batteries. Commercially available batteries used for operating electric cars are suitable. Lithium-ion batteries are particularly suitable.

[0035] The one or more batteries can be charged from a power grid or another power source, such as a photovoltaic system, a wind turbine, or a biogas plant directly via a power cable. The tractor according to the invention is electrically connected to a combination on-board charging system, which can preferably be connected bidirectionally to the electrical AC grid. This system can reverse the energy flow as needed, so that on the one hand the battery can be charged from the grid or, for example, from a photovoltaic system or wind turbine, and the stored energy can be fed back into the grid or to other consumers as needed. The battery can thus be used bidirectionally, i.e. on the one hand it can absorb and store power, and on the other hand it can feed stored power to supply external electrically operated devices with three-phase current.For this purpose, the electric tractor according to the invention has one or more standardized, commercially available sockets that can be used for power input or as power outputs. This allows the electric tractor to be used as a mobile power source independent of a power grid. If the driving operation of the electric tractor according to the invention is carried out indirectly via hydraulic motors acting on one or more drive axles or multiple drive wheels, the hydraulic motor(s) can have one gear or, preferably, two gears. With two-speed hydraulic motors, the speed of the first gear is preferably a maximum of 13 km / h with a tractive force between 7-12 kN. In the second gear, the speed is preferably a maximum of 40 km / h with a power between 4-7 kN.

[0036] The connecting element 2 between the rear tractor section 4 and the front tractor section 3 can be constructed from one or more angular profiles or tubes. The connecting element 2 is made of steel or dimensionally stable plastic, for example Kevlar. This connecting element 2 must not significantly impair the driver's visibility and has a width of a maximum of 50 cm, preferably a maximum of 40 cm, and most preferably a maximum of 30 cm in area a) (this is the area from the height of the wheel hub, starting 2 m upwards along the connecting element 2). The connecting element 2 can be designed, for example, as a hollow body, a U-profile, a double U-profile, a T-profile, a double T-profile, or a triangular profile. In this way, lines, cables, or hydraulic hoses can be routed within the connecting element 2 or attached to the connecting element 2 without significant loss of visibility for the driver.The distance from the bottom edge of connecting element 2 to the ground surface is at least 150 cm, including the mounted wheels. This ensures that the attached implements, such as hoeing tools, can be raised high enough from the ground in the center of the tractor.

[0037] The electric tractor according to the invention is equipped with a control system that optimally controls all hydraulic and electrical drive components, ensuring maximum efficiency at every operating point. The control and regulation of the electric motors and hydraulic components is achieved according to the invention in such a way that all components operate with maximum efficiency at every operating point of the tractor. This allows for better utilization of the battery capacity. For the selected operating time, a smaller battery can be selected, resulting in lower costs.

[0038] Additionally, the electric tractor can be equipped with an autopilot system. The autopilot system processes information from the electric tractor's instruments, sensors, cameras, and GPS and automatically keeps the electric tractor in the desired crop path.

[0039] The control system of all hydraulic and electric drive components can be connected to the autopilot system. This provides the control system with additional information from the autopilot system, such as position, inclination, acceleration, and speed, and improves the efficiency of the electric tractor through an internal algorithm.

Claims

1. Tractor for agricultural use having a chassis (1), which connects a front tractor part (3) and a rear tractor part (4) to one another via a connecting element (2), a driver's seat (5) in the region of the rear tractor part (4), a drive (6) and at least four wheels (7a, 7b), wherein the connecting element (2) of the chassis (1), which connects the rear tractor part (4) and the front tractor part (3) to one another, is arranged at least 60 cm above the driver's seat (5) and extends essentially horizontally to the front tractor part (3), characterised in that the front tractor part (3) and the rear tractor part (4) are connected with a single connecting element (2),which is arranged in the centre between the rear wheels (7b) and in the centre between the front wheels (7a) and the driver's seat (5) is arranged to the right or left of the connecting element (2), so that the driver has a clear view to the front and also to the side of an implement mounted in the centre of the tractor and has an unobstructed view when driving straight ahead and to the side of the road..

2. Tractor according to claim 1, characterised in that the connecting element (2) of the chassis (1), which connects the rear tractor part (4) and the front tractor part (3) to one another, is arranged at least 70 cm, preferably at least 80 cm, above the driver's seat.

3. Tractor according to any one of the preceding claims, characterised in that the wheels (7a, 7b) are individually suspended and individually driven.

4. Tractor according to any one of claims 1 to 3, characterised in that pairs of rear wheels (7b) or pairs of front wheels (7a) are each connected via an axle and are jointly driven via the connecting axle.

5. Tractor according to any one of the preceding claims, characterised in that at least one electric motor is provided as the drive (6).

6. Tractor according to claim 5, characterised in that the electric motor acts on the rear wheels (7).

7. Tractor according to any one of the preceding claims, characterised in that an all-wheel drive is provided.