DE102018216089A1 - Drive for a four-wheel drive vehicle with four wheels - Google Patents

Abstract

Drive (1) for an all-wheel drive vehicle with four wheels (3), two of which form the front wheels (3V) and two form the rear wheels (3H), as well as two drive motors (5) for driving the wheels (3) and two drive shafts (7) , which are each assigned to a drive motor (5) and two wheels (3) in order to transmit a rotary movement of the drive motor (5) to the two associated wheels (3), a drive shaft (7) having a left front wheel (3V) and a left rear wheel (3H) and the other drive shaft (7) drives a right front wheel (3V) and a right rear wheel (3H).

Description

The invention relates to a drive for a four-wheel vehicle with four wheels and the use of the drive for a maintenance machine.

Drives for driving motor vehicles are well known. A conventional car with a motor and four wheels typically has a front or rear wheel drive, with the vehicle being steered via the two front wheels. In these cases, the two front wheels and the two rear wheels are each arranged on one axle, namely the front and the rear axle. Differences in speed between the wheels of the front and rear axles can be compensated for.

All-wheel drive is used in conventional automobiles, in particular sports cars, with one engine and four driven wheels, particularly when the engine is at high power, in order to achieve sufficient traction. All-wheel drive is used in conventional automobiles, in particular off-road vehicles, with one motor and four driven wheels in order to achieve good off-road mobility of the vehicle, even if one or two wheels are not in contact with a surface, the four-wheel vehicle is driven by these remaining wheels possible with the differential lock switched on, in which case the steering ability is reduced. In both cases, the front and rear wheels are arranged on a front and rear axle, respectively, with a differential compensating for the speed differences between them.

Semi-trailers with a tractor and a trailer are also known, the trailer having two or more axles with associated wheels, the wheels of one axle having a certain steerability in order to steer the trailer in a desired direction. The expression “certain steerability” refers to the fact that the wheels can only be steered over a small angular range, for example only 10-20 °.

In a forklift truck, the front wheels are arranged on a rigid front axle in order to be able to carry heavy loads with the forklift truck. The two wheels on a rear axle of the forklift are used to steer it.

• Mit herkömmlichen Allradfahrzeugen lassen sich bestimmte Lenkmanöver nur beschränkt und/oder mit erhöhtem technischen Aufwand realisieren: In 1a) ist bspw. eine Allradlenkung dargestellt, bei der die Vorderräder 3V nach rechts und die Hinterräder 3H nach links geneigt sind, um einen kleinen Wendekreis zu ermöglichen bzw. enge Kurven fahren zu können. In 1b) ist ein Hundegang gezeigt, bei dem alle Räder 3V, 3H in die gleiche Richtung zeigen und dies unter einem Winkel zur Längsachse des Fahrzeugs von rund 45°. Auf diese Weise ist ein Querversatz des Fahrzeugs besonders einfach zu erreichen. In 1c) ist eine Ortslenkung dargestellt, bei der die Vorder- und die Hinterräder 3V, 3H jeweils unter 45° nach innen geneigt sind, um eine Drehung auf der Stelle zu ermöglichen.

The known drives for all-wheel drive vehicles with one engine and four wheels have in common that they offer only limited possible uses in certain areas of application or have only limited maneuverability:

• With conventional all-wheel drive vehicles, certain steering maneuvers can only be carried out to a limited extent and / or with increased technical effort: In 1a) an all-wheel steering is shown, for example, in which the front wheels 3V to the right and the rear wheels 3H are inclined to the left to allow a small turning circle or to be able to make tight turns. In 1b) is shown a dog walk with all wheels 3V , 3H point in the same direction at an angle of around 45 ° to the longitudinal axis of the vehicle. In this way, a transverse offset of the vehicle is particularly easy to achieve. In 1c ) is shown a steering system, in which the front and rear wheels 3V , 3H are inclined inward at 45 ° to enable rotation on the spot.

Conventional all-wheel drive vehicles have an increased technical outlay, for example a differential lock and / or a longitudinal differential, in order to be able to carry out such steering maneuvers, but can usually not perform these steering maneuvers at all or only in the beginning.

All-wheel drive vehicles as maintenance machines for tillage, e.g. for milling and scarifying and plowing a soil, or for green area maintenance, e.g. for mowing grass, or for area maintenance, e.g. sweepers, however, especially require these expanded or better applications, for example regarding maneuverability or controllability in the field or in a confined space.

Since these all-wheel drive vehicles are to be operated increasingly autonomously and should also be suitable for use on steep slopes, there are additional requirements for the applicability of such vehicles.

It is therefore an object of the present invention to provide a drive for an all-wheel drive vehicle with four wheels, which meets the increased demands on usability and requires only a small amount of technical effort.

According to the invention, this object is achieved by the features of claim 1 and the use according to the further independent claim.

At least one drive motor is advantageously selected from a group consisting of an electric motor, gasoline engine, diesel engine, hybrid engine or controllable hydraulic motor.

At least one drive motor and the associated drive shaft preferably each have one Pulley on and runs between them a toothed belt to transmit a rotary movement of the drive motor to the associated drive shaft.

At least one drive shaft is advantageously a cardan shaft.

Each wheel is preferably assigned a gear, in particular a worm gear, which converts the rotary movement of the respective drive shaft to the associated wheel.

A steering cylinder and an angular gear are preferably assigned to each wheel, one end of each steering cylinder being fixedly connected to the all-wheel-drive vehicle and one end to the angular gear in order to move the associated wheel in a desired direction.

The four-wheel drive vehicle is advantageously a maintenance machine for area maintenance, for example a sweeper, a maintenance machine for green area maintenance, for example a mower, or a maintenance machine for tillage, for example a machine for scarifying or plowing a soil.

The use of the drive according to the invention for driving a care machine is advantageous.

• 1 a) eine Allradlenkung eines Allradfahrzeugs, bei der die Vorderräder nach rechts und die Hinterräder nach links lenken, um einen möglichst geringen Wendekreis des Allradfahrzeugs zu ermöglichen,
• 1 b) eine Hundeganglenkung eines Allradfahrzeugs, bei der die Vorderräder und die Hinterräder in die gleiche Richtung lenken, um einen Versatz des Allradfahrzeugs auf einfache Weise zu ermöglichen,
• 1 c) eine Ortslenkung eines Allradfahrzeugs, bei der die Vorderräder und Hinterräder jeweils 45° nach innen geneigt sind, um das Allradfahrzeug auf der Stelle zu drehen,
• 2 eine schematische Draufsicht auf einen erfindungsgemäßen Antrieb eines Allradfahrzeugs mit vier Rädern, und
• 3 eine schematische Seitenansicht des Antriebs der 2, bei der die Räder um 90° nach außen gedreht sind, um die Winkelgetriebe darzustellen.

Further features, details and advantages of the invention emerge from the claims and the following description of preferred embodiments and from the drawing. Show it:

• 1 a) an all-wheel steering of an all-wheel drive vehicle, in which the front wheels steer to the right and the rear wheels to the left, in order to enable the smallest possible turning circle of the all-wheel drive vehicle,
• 1 b) a crab steering of a four-wheel drive vehicle, in which the front wheels and the rear wheels steer in the same direction, in order to enable the four-wheel drive vehicle to be displaced in a simple manner,
• 1 c) a steering of an all-wheel drive vehicle, in which the front wheels and rear wheels are each inclined 45 ° inwards in order to turn the all-wheel drive vehicle on the spot,
• 2nd is a schematic plan view of an inventive drive of a four-wheel vehicle with four wheels, and
• 3rd is a schematic side view of the drive of the 2nd , with the wheels turned outwards by 90 ° to show the angular gear.

2nd shows a drive 1 an all-wheel drive vehicle that has four wheels 3rd has, namely two front wheels 3V and two rear wheels 3H . How to 2nd can see, the drive is symmetrical, ie the in 2nd left half of the drive 1 is symmetrical to that in 2nd right half of the drive, which is why only the right half is described below.

From a drive motor 5 , in the present case an electric motor, rotates on a pulley 9 transmitted, from which it uses a toothed belt 11 on a pulley 9 on a drive shaft 7 is transmitted.

On the in 2nd upper and lower ends of the drive shaft 7 is a worm gear 13 arranged, the rotational movement of the drive shaft 7 on the respective associated wheel 3V , 3H transmits. Because the two of a drive shaft 7 assigned wheels 3V , 3H the same drive shaft 7 are assigned and the worm gear 13 are the same, the speed is that with the drive shaft 7 connected wheels 3V , 3H also the same.

Every bike 3V , 3H is a steering cylinder 15 with associated bevel gear 17th assigned to the associated wheel 3V , 3H to steer or turn in a desired direction. The steering cylinder 15 is firmly connected to the four-wheel drive vehicle at one end and engages with the other end in the angular gear 17th that the lifting movement of the steering cylinder in a rotary movement of the associated wheel 3V , 3H implements. The wheels 3rd are present from their zero position (wheel axis perpendicular to the vehicle, see 2nd ) can be rotated through 45 ° in any direction (steered to the right or left from the zero position).

3rd shows a side view of the 2nd from the direction labeled III. The drive train of each wheel is shown 3V , 3H by the drive motor 5 , over the pulleys 9 and the timing belt 11 to the drive shaft 7 leads, their rotary motion via the worm gear 13 at both ends of the drive shaft 7 the respective wheel 3V , 3H sets in rotation, the speed of the two wheels 3V , 3H is equal to. Furthermore, the 3rd the angular gear 17th can be seen from the steering cylinder 15 the rotation of the associated wheel 3V , 3H carries out. The wheels 3V , 3H are 90 ° to the 2nd turned outward to the bevel gear 17th to represent.

In the embodiment of the 2nd and 3rd are the wheels on one side of the all-wheel-drive vehicle each through a common drive shaft 7 coupled and driven together. Another implementation of the drive train, in the present case from the drive motor 5 over the pulleys 9 and the timing belt 11 on the drive shafts 7 to the worm gear 13 and the wheels 3rd leads is possible. In an alternative embodiment, for example, each wheel 3V , 3H an electric motor or a hydraulic motor, the motors being controlled so that the speed of the wheels 3V , 3H the right and left sides of the four-wheel drive vehicle are the same.

In the present case, the rotary motion of the two drive motors 5 on the respective drive shaft 7 by means of a toothed belt 11 and pulleys 9 transfer. However, the transmission can alternatively take place by means of the further techniques known in the prior art, for example by means of a cardan shaft, V-belt, chain or gear wheels.

In the present embodiment, a worm gear was in the drive train 13 for turning and steering the wheels 3V , 3H an angular gear 17th used. Other gears that are suitable for the respective application are known to the person skilled in the art, so that the use of different gears is possible.

Would be the steering cylinders 15 of the drive according to the invention 1 connected to each other, would be a local control 1c ) not possible. Due to the independence of the steering cylinder 15 can the three types of steering the 1 realize the extent of the steering of each wheel 3rd and thus the extent to which the steering types of the 1 can be realized by the respective steering cylinders 15 and the bevel gear 17th or depends on the angular range that the respective wheels 3V , 3H steer or turn.

The larger the angular ranges within which the respective wheels are 3V , 3H turn or steer, the greater the extent of steering or maneuverability and thus the extent to which the types of steering 1 let it be realized. The larger the size, the greater the possible uses of the all-wheel drive vehicle.

Do the steering cylinders 15 a large stroke and / or the associated bevel gear 17th a large gear ratio, large rotation angles of the wheels 3V , 3H realize. Do the steering cylinders 15 only a short stroke and / or the associated bevel gear 17th a low gear ratio, only small rotation angles of the wheels 3V , 3H achieve.

All four wheels are preferred 3V , 3H the same steering cylinders 15 , especially with a long stroke, and angular gear 17th assigned with a large gear ratio in order to ensure that the respective wheels can be rotated as much as possible 3V , 3H to reach.

However, it is possible for the front wheels 3V Steering cylinder 15 with a smaller / larger stroke and angular gear 17th to use with a smaller / larger gear ratio and for the rear wheels 3H Steering cylinder 15 with a larger / smaller stroke and angular gear 17th to be used with a larger / smaller gear ratio, depending on the intended use of the all-wheel drive vehicle. Alternatively, it is possible for the wheels 3V , 3H a steering cylinder on the left 15 with a smaller / larger stroke and an angular gear 17th to use with a smaller / larger gear ratio and for the wheels 3V , 3H a steering cylinder on the right 15 with a larger / smaller stroke and an angular gear 17th to use with a larger / smaller translation.

The greatest possible maneuverability or maneuverability and thus the greatest possible applicability of the drive 1 and thus to be able to reach the all-wheel-drive vehicle are the largest possible rotation angles of the individual wheels 3V , 3H advantageous. In the drive according to the invention 1 point the wheels 3V , 3H each have an angle of rotation of -45 ° to + 45 ° based on their zero position. The wheels can be rotated in a larger angular range, for example rotation angles of greater than 60 ° are also possible. With respect to the zero position, the wheels can preferably be rotated in each direction by the same angular amount as in the present case by 45 ° in each direction. Alternatively, it is possible that at least one wheel can be rotated in one direction, for example to the right, by a larger / smaller angular amount than it can be rotated in the other direction. Will the drive of the invention 1 used in maintenance machines, so all wheels are preferably rotatable from their zero position in any direction by at least 45 ° to the in 1 to be able to implement the types of steering shown.

Generally, an all-wheel drive vehicle would have a front and a rear axle on which the front and rear wheels, respectively 3V , 3H would be arranged and via which a front or a rear wheel steering would be realized, a differential lock and / or a longitudinal differential would be necessary to the steering types 1 to realize what leads to an increased technical effort. In particular the 1b and 1c Steering types shown require rotatable or steerable rear wheels 3H , which must also be controlled to the correct angle in accordance with the selected type of steering. The local steering according 1c would still not be possible, however, because for this type of steering the wheels 3V , 3H the left side should have a different rotation than the wheels 3V , 3H the right side of the four-wheel drive vehicle.

In the drive according to the invention 1 an all-wheel drive vehicle drives a drive shaft 7 the two left wheels 3V , 3H and a drive shaft 7 the two right wheels 3V , 3H of the all-wheel-drive vehicle. The speed of the two wheels 3V , 3H One side (left or right side) of the all-wheel-drive vehicle is defined and the same without using a differential. In this way, the drive types or steering types of the 1 Realize in a particularly simple manner and very well in terms of their controllability, this being done without the use of a differential, for example a differential lock or a longitudinal differential, so that no increased technical outlay within the drive 1 is required. The extent to which the in 1 have the types of steering shown implemented. A high degree of rotatability (over a large angular range) of the wheels is advantageous in order to be able to implement the steering modes as well as possible (to the greatest possible extent) and thus to enable the all-wheel-drive vehicle to be used to a high degree.

For the drive according to the invention 1 is thus the arrangement of the wheels 3V , 3H one side of the all-wheel drive vehicle on a drive shaft 7 crucial, reducing the speed of the wheels 3rd one side is the same. This coupling of the wheels 3rd one side with the elimination of any differential allows the in 1 to realize the types of steering shown in a simple manner. The extent to which the types of steering can be implemented depends on the steerability or turnability of the wheels 3rd as described above.

The drive according to the invention is particularly suitable for use in maintenance machines for area maintenance, in maintenance machines for green area maintenance and in maintenance machines for soil cultivation, since these machines in particular require increased usability in the field, in particular increased maneuverability or steerability and also predetermined speeds of the wheels 3V , 3H to ensure maximum power transmission to the ground or floor regardless of the steering angle of the wheels 3V , 3H to reach.

In the present exemplary embodiment, the speed of the wheels is calculated 3V , 3H based on the steering angle of the wheels 3V , 3H (measured using angle sensors on each wheel 3V , 3H) and thus the selected steering type (this can be one of the steering types of the 1 or a forward or backward drive of the all-wheel drive vehicle) and the selected driving speed. The result of the calculation is the desired target speed of the wheels 3V , 3H . On the basis of this result, a corresponding control signal is sent to the respective engine 5 , which is set to a speed at which the wheels 3V , 3H rotate at the calculated target speed. The calculation is carried out separately for each side of the four-wheel drive vehicle, ie for the right and left side.

By the drive according to the invention 1 can thus be driven an all-wheel drive vehicle that can drive forward and backward in a conventional manner, but at the same time that in 1 shown steering types resolves in a particularly good and technically simple manner. Because the types of steering 1 are particularly desired in maintenance machines, since often only a limited space is available for turning or steering maneuvers on the surfaces to be maintained, the drive according to the invention is particularly suitable for these maintenance machines.

It is advantageous if the maintenance machines are autonomous four-wheel drive vehicles, so that they are as small as possible and can also be active at times and in places where people are rarely active. The autonomous all-wheel drive vehicles can do their jobs at night, eliminating night work for operators of the all-wheel drive vehicles. They can also be active near train tracks or airports without endangering an operator. The route of the maintenance machines can be specified in any way known in the prior art, for example by GPS or by following a guide vehicle or by independent driving in a predetermined area which is defined by certain cables laid in the ground and with which the all-wheel drive vehicle in Communication is there. In an advantageous embodiment of the invention, the drive according to the invention is used in a maintenance machine or a maintenance machine has the drive according to the invention. The maintenance machine has exactly four wheels, all of which are driven. The maintenance machine can drive forwards and backwards and is set up, in particular only with the three types of steering 1 to be directed. The wheels on one side of the maintenance machine, ie the wheels on the right or left side, are set up to be driven only at the same speed. There is no differential in the drive train on each side of the maintenance machine. It is preferred that the care machine is set up to drive autonomously.

Reference list

1

Drive for an all-wheel drive vehicle

3rd

wheel

3H

Rear wheel

3V

Front wheel

5

Drive motor

7

drive shaft

9

Pulley

11

Timing belt

13

Worm gear

15

Steering cylinder

17th

Angular gear

19th

Axis of rotation

Claims (9)

Drive (1) for an all-wheel drive vehicle with four wheels (3), two of which form the front wheels (3V) and two form the rear wheels (3H), as well as two drive motors (5) for driving the wheels (3) and two drive shafts (7) , which are each assigned to a drive motor (5) and two wheels (3) in order to transmit a rotary movement of the drive motor (5) to the two associated wheels (3), a drive shaft (7) having a left front wheel (3V) and a left rear wheel (3H) and the other drive shaft (7) drives a right front wheel (3V) and a right rear wheel (3H). Drive after Claim 1 , characterized in that at least one drive motor (5) is selected from a group consisting of an electric motor, gasoline engine, diesel engine, hybrid engine or controllable hydraulic motor. Drive after Claim 1 or 2nd , characterized in that at least one drive motor (5) and the associated drive shaft (7) each have a pulley (9) and a toothed belt (11) runs between them in order to rotate the drive motor (5) onto the associated drive shaft (7) transferred to. Drive according to one of the preceding claims, characterized in that at least one drive shaft (7) is a cardan shaft. Drive according to one of the preceding claims, characterized in that each wheel (3) is assigned a gear (13), in particular a worm gear, which converts the rotary movement of the respective drive shaft (7) to the associated wheel (3). Drive according to one of the preceding claims, characterized in that each wheel (3) is assigned a steering cylinder (15) and an angular gear (17), one end of each steering cylinder (15) being fixed to the all-wheel-drive vehicle and one end to the angular gear ( 17) is connected to move the associated wheel (3) in a desired direction. Drive according to one of the preceding claims, characterized in that the all-wheel drive vehicle is a maintenance machine for area maintenance, for example a sweeper, a maintenance machine for green area maintenance, for example a mower, or a maintenance machine for tillage, for example a machine for scarifying or plowing of a floor. Use of a drive according to one of the preceding claims for driving a care machine. Use according to the preceding claim, characterized in that the maintenance machine is a maintenance machine for area maintenance, for example a sweeper, a maintenance machine for green area maintenance, for example a mower, or a maintenance machine for tillage, for example a machine for scarifying or plowing Floor.

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