Patent Application
20050072254
From the vehicle technology transmissions which comprise one input shaft and one output shaft are known. In addition, it is possible to provide a countershaft in the main transmission which actuates a power take off. It is also possible to rear mount a range change group on the main transmission. But in the already known transmission, the ratio steps for the power take off (PTO) are disadvantageously limited.
Publication DE 199 22 116 A1 has disclosed also a two-countershaft transmission. The two-countershaft transmission makes it possible to reduce a torque for the power take off without at the same time disturbing the load compensation of a gear wheel between the two countershafts so that a PTO operation no longer depends on the engaged gear and the centering of the constant can be eliminated. This is specifically obtained by the power take off shaft used being driven by a power take off wheel, via a main shaft wheel, the radial force between the power take off wheel and the main shaft wheel being absorbed by a plate mounted on the power take off shaft and on the main shaft wheel.
The problem on which the invention is based is to propose a transmission of the above mentioned kind in which the ratio step possible for the power take off are increased.
According to the invention this problem is solved by the features of claim 1. Advantages and further developments result from the sub-claims.
An inventive transmission for a vehicle is accordingly proposed in which a countershaft integrated in the range change group is provided for the transmission system of a power take off. The countershaft can be connected, via a gear change sleeve unit, with the input shaft and/or the output shaft according to the shifting state, the power take off being actuatable independently of an operating state of the vehicle. In this manner, the maximum number of available ratio steps for the power take off operation results from multiplication of the number of ratio steps of the main transmission and the number of ratio steps of the range change group. When additional groups are associated with the main transmission, the number of ratio steps available for the power take off range can increase further.
Within the scope of an advantageous development of the invention, the gear change sleeve unit can be provided with at least two gear change sleeves, it being preferred that the first gear change sleeve be located upon the input shaft and the second gear change sleeve upon the output shaft. The two gear change sleeves are situated on the shafts, respectively, axially displaceably and fixedly. The gear change sleeve unit can also have more than two gear change sleeves.
According to the invention, both gear change sleeves of the gear change sleeve unit are coupled, in an axial direction, via a connecting plate or the like with the connecting plate being actuatable via a shift fork.
One development of the invention can provide that the countershaft, integrated in the range change group, has a first wheel as a first ratio step and a second wheel as a second ratio step so that at least one two-step ratio can be implemented for the power take off. It is conceivable also to increase the number of ratio steps in the range change group.
With the gear change sleeve unit, different shifting states can be implemented for the power take off in the range change group. It is thus possible that the power take off is actuatable both when the vehicle is moving and when it is parked.
The invention is explained in detail herebelow with reference to the enclosed drawing wherein:
In FIGS. 1 to 5 is shown a possible embodiment of the inventive transmission for a vehicle. The transmission comprises a main transmission (not shown in further detail) with one input shaft 1 provided as intermediate shaft of the main transmission and one output shaft 2, the same as a range change group 3 and a power take off.
It is provided according to the invention that for actuating a power take off, which is indicated with an arrow 4 in FIGS. 1 to 4, a countershaft 5, integrated in the range change group 3 is provided. The countershaft 5 is connected, via a gear change sleeve unit 6, with the input shaft 1 and/or the output shaft 2 according to the shifting state. In this manner, the power take off is driven independently of the operating state of the vehicle.
Diagrammatically indicated in
In this embodiment, the countershaft 5 has two wheels 11, 12. The first wheel 11 forms the first ratio step I and the second wheel 12 forms the second ratio step II of the range change group 3. The first ratio step I is designated as ratio iStep I and the second ratio step II as ratio iStep II. In this manner, by virtue of the inventive transmission, different gear change states are implemented for the power take off by the gear change sleeve unit.
In
In
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In
In the inventive transmission shown here, the power take off in the range change group 3 is driven via the countershaft 5, the power take off being doubly shiftable by the two countershaft wheels 11, 12. It is to be observed here that as ratio step the number of gears of the rest of the transmission is added. In this manner, the number of ratio steps available for the power take off results from the modification of the number of ratio steps of the main transmission and the number of ratio steps of the range change group 3.
In instant invention thus proposes a transmission in which, especially by virtue of the gear change sleeve unit, the existing ratio steps can be used for the power take off both during the down time of the vehicle and also during the driving state.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102 41 743.1 | Sep 2002 | DE | national |
