DE19802371A1 - Drive arrangement for a tandem axle - Google Patents

Description

The present invention relates to a drive assembly tion for a drive axle of a self-propelled work machine no. It is a tandem axle with two on both Two-armed swing arms arranged on the sides of a chassis. At the ends of these wings are the driven ones Bikes.

Such vehicles or work machines are for example as Construction, agricultural or forestry machines are used in rough terrain puts. The rotation is initiated by a prime mover moments via a cardan shaft, a differential gear and a Planetary gear in the swinging axis of the rocker. One of the like drive arrangement is known from DE-AS 25 22 542. In this known arrangement is the initiation of the rotation moments in the swing arm via a swingable in the vehicle frame mounted axle tube.

In contrast, for driving that can be used in rough terrain I prefer to just move the swing arm directly to the vehicle frame to arrange their swing axis swingable. The deflection, distribution and Reduction gears don't just have to be for smooth Distribution of torque to the driving wheels, rather also - and that is the essential task of the present Invention - for a constant grip of the wheels in the rough seedy terrain. In particular, in an intermediate planetary gears did not switch the gears momentarily Are exposed to counter-torques from the drive wheels in difficult terrain can be generated without immediately for to provide compensation.

This problem is solved according to the present invention tion generally in the fact that a second planetary gear so one is added that the ring gear of the reduction planetary gear bes is supported on the sun gear of the second planetary gear. The ring gear of the second planetary gear is fixed to the Swing arm and the web of the second planetary gear is fixed with connected to the chassis. This creates between driving frame and the swingarm a "measuring" and compensating planetary tightness shoots. That gelie from the differential to the main planetary gear The specified shaft torque is translated in the "measuring gear" and is the same This torque is timely due to a supporting moment in the tooth wreath, which is proportional to the input or output torque, measured. This supporting moment is due to the second planetary ge drive in at the point at a distance from the oscillation axis the swing arm initiated.

The effect of the two torques results in advantageous sometimes a sufficiently large restoring torque that is achieved by correct choice of gear ratios to meet the demands of the Practice can be adjusted.

It is known from DE 41 20 801 C2, two planetary ge to install drives in the path between the differential and the swing arm. But these two planetary gears are connected in series. The ring gear of the planetary gear on the drive side is supported here on the chassis and the ring gear of the wheel-side tarpaulin The gearbox is supported by the swing arm. This too If necessary, the arrangement generates a restoring torque. There Here, however, the planet gears of both gears are the same size are, the same translations result, which is directly an drive way is also useful.

In contrast, the gear ratio between main and "Measuring" transmission according to the present invention is more advantageous wisely designed differently depending on the requirements of the practice be.

Further details, features and advantages emerge from the following description of a graphically shown Aus management example and a numerical example compared to the State of the art.

The drawing shows in section an embodiment of the invention. A rocker arm 10 is articulated in the bearing 12 on a chassis 14 . A drive shaft 20 , connected to a multi- disk brake 30 , extends from a differential (not shown) to a sun gear 42 of a first measuring planetary gear 40 . As is known, the web 44 of this transmission 40 carrying planetary gears 46 is connected to an output shaft 60 which runs coaxially to a swing axis 62 and is mounted in bearings 64 in the swing arm 10. On this output shaft 60 sits a gear 70 which, as is known, meshes with other gears 72 on both sides of the rocker arm 10 in order to transmit the torque to the wheels, not shown here, which sit at both ends of the rocker arm 10.

The planet gears 46 roll on a ring gear 48 which is connected to a sun gear 52 of a second or “rotating” planetary gear 50 . Planetary gears 56 seated on a web 54 roll on a ring gear 58 which is firmly connected to the rocker arm 10 . The web 54 is firmly connected to the chassis 14 a related party.

It should be noted that the rocker 10 also continues above the gear 70 in the present illustration to a second drive wheel, not shown, although not in the plane of the drawing of the illustration shown. The rocker 10 need not be designed to be stretched. In practical implementation, the rockers often form a downwardly bent obtuse angle with the axis 62 as a Schei tel, as indicated in Fig. 3 of DE 41 20 801 C2.

In the following an exemplary embodiment is given numbers. This is based on an axis with the following assumptions:

AL = L <axis 16,000 kg Tire radius 570 mm Swing cant 200 mm wheelbase 1500 mm Coefficient of friction 0.8 translation 23.294

Distribution of translations

Total: 2,067.3.0,7878.1,052.4.53 = 23.28

Wheel torque at µ = 0.8; r = 0.57 m and 8 t load (= 80 kM)

M _wheel = 80,000.0,8.0,57 = 36,480 Nm

Support moment of the ring gear of the measuring planet 40 :
3239. (i _{M ei} -1) = 6478 Nm
= Input torque in the rotating planet

Output torque in the rotating planet 50 :
6478.4 = 25,912 Nm

Output torque central spur gear 70 :
= 3239.i _MA = 3239.3 = 9717 Nm

Total restoring torque of the rocker arm 10 :
M _RS = 25 911 + 9717 = 35 628 Nm

Setup moment due to tensile force:
Pulling force: 80,000.0.8 = 64,000
M _A = 64,000 (0.57 + 0.2) = 49,280 Nm

Differential torque:
M _D = 49 280 - 35 628 = 13 652 Nm

Wheel load 1: 40,000 - 9101 = 30,899 N
Wheel load 2: 40,000 + 9101 = 49,101 N

Comparison with a rocker according to DE 41 20 801 C2 with the same output data and effective ratio 1.82:

Setup torque: M _A = 49 280 Nm

Differential torque: 49 280 - 20 043 = 29 236 Nm

Wheel load 1: 40,000 - 19,490 = 20,510 N
Wheel load 2: 40,000 + 19,490 = 59,490 N

better or balanced.

To get the same "degree of compensation" as with a solution according to To have DE 41 20 801, an effective translation of 1.376 would have to be achieved be, d. H. a BB planetary gear ratio of 7.57 (instead of 5.71). Since the same torque ver must be worked as with 5.71, would be a larger space (∅ approx. 30% larger) required.

For example

Diameter of the ring gear: 36% 90.4.5 = 405 @ 66.4.5 = 297

This in turn requires a larger turntable, larger support wreath and more height on the swing arm.

In comparison to the state of the art, with regard to Pressure forces on the ground and with regard to the structural dimensions are the same good or better values.

Claims (2)

1. Drive arrangement for a drive axle of a self-propelled work machine, even in rough terrain, with two-armed rocker arms arranged on both sides of a chassis, at the outer ends of which there are driven wheels, the drive torque being passed into each rocker arm via a planetary gear in the rocking axis of the rocker arm , characterized in that the ring gear (48 ) of the planetary gear ( 40 ) with the sun gear ( 52 ) of a second planetary gear ( 50 ), the ring gear (58 ) of the second planetary gear ( 50 ) fixed to the rocker ( 10 ) and the web ( 54 ) of the second planetary gear ( 50 ) is firmly connected to the chassis ( 14 ) at a distance from the oscillating axis ( 62 ). 2. Drive arrangement according to claim 1, characterized in that the second planetary gear ( 50 ) with respect to the first planetary gear ( 40 ) by different sized plane tenräder ( 46 , 56 ) translate differently.