Planetary gear transmission systems or components – With means to vary drive ratio or disconnect drive – Orbit braked
Patent
1990-08-31
1992-09-29
Braun, Leslie A.
Planetary gear transmission systems or components
With means to vary drive ratio or disconnect drive
Orbit braked
475141, 192 8711, 192 8714, F16H 344
Patent
active
051510685
DESCRIPTION:
BRIEF SUMMARY
The invention concerns a driving mechanism, especially for mobile excavators and similar construction machines, which has a power-shiftable two-gear transmission driven by a prime mover, two speed levels alternatively engageable and disengageable via hydraulically shiftable friction clutches, and an oil pump for supplying pressurized and lubricating oil to the transmission, one of said friction clutches being designed as spring accumulator clutch controllable by oil pressure
For construction machines such as mobile excavators and wheel bearings which can travel quicker than 25 km/h, the legislator has established different requirements and directive relative to the brakes. In a single-circuit braking system, there must be an auxiliary service brake together with the normal service brake A parking brake is likewise required
EP-B1-0 070 420 has disclosed a driving mechanism for a mobile excavator which includes the above features. In said publication a parking brake designed as shoe brake is situated on an output shaft. Such a brake is actuated by oil pressure. This requires a brake control line which in a wheel excavator, for instance, must be conveyed from the upper chassis to the lower chassis through the rotary guiding duct. In any case, such a parking brake requires a certain installation space which is limited, especially in the case of wheel loaders and also in mobile excavators.
The problem to be solved by the invention is to adapt a driving mechanism of the kind mentioned above to the limited installation space in mobile excavators and similar construction machines and to obtain a simplification of the brakes and of the direction of the hydraulic pipes.
In the driving mechanism said problem is solved by the fact that both friction clutches are designed as spring accumulator clutches controllable by oil pressure which are radially telescoped, serving both for shifting the gears and as a parking brake and an auxiliary service brake. The radially external friction clutch is designed as a brake. At the same time the driving mechanism is compacted by telescoping the friction clutches. A parking brake and a separate line for actuating such brake can be eliminated.
If for the first gear, which can also be called the cross-country gear, the radially external larger friction clutch is engaged, then said clutch must be capable of absorbing a multiple of the input torque. But since in the second gear, shifted by the engaged internal friction clutch, the radially external larger friction clutch is disengaged, then at the higher speeds occurring in the second gear, the external clutch can absorb a great braking energy when braking. The heat appearing during braking can be dissipated via the housing. The internal, smaller friction clutch must transmit in second gear only part of the input torque so that said clutch can be designed smaller. When braking in first gear at lower traveling speed, the radially internal clutch must absorb only a small braking energy. The slight heat that generates then is eliminated by appropriate lubrication. Therefore, the internal smaller friction clutch and the external large one are adapted, with the smallest dimensions, to the torque to be transmitted at any given time.
By disposing a separating clutch between the two-gear transmission and the spur gear set, it is possible to interrupt the transmission line when the vehicle is towed in case of emergencies or for relocation. By virtue of the separating clutch, the drive of the transmission line is limited starting on the load side to the range of the spur gear set. The planetary-gear set of the two-gear transmission, the friction clutches and the prime mover are not rotated along.
The invention is not limited to the combination of features of the claims Other logical possible combinations of claims and individual features thereof result for the expert according to the problem to be solved.
The invention is explained in detail herebelow with reference to an embodiment shown in the drawings. In the drawings:
FIG. 1 diagrammatically s
REFERENCES:
patent: 3069929 (1962-12-01), Hansen
patent: 4026167 (1977-05-01), Archer
patent: 4128023 (1978-12-01), Kinder
patent: 4178814 (1979-12-01), Ahlen
patent: 4516444 (1985-05-01), Herr, Jr.
patent: 4732253 (1988-03-01), Hiramatsu et al.
patent: 4741422 (1988-05-01), Fuehrer et al.
patent: 4955852 (1990-09-01), Morisawa
patent: 4971185 (1990-11-01), Hayakawa et al.
patent: 5024636 (1991-06-01), Phebus et al.
Froslie et al., "Ratio Change-Friction Elements", Design Practices-Passenger Car Automatic Transmission vol. 5, 1988, (SAE, Warrendale PA) pp. 116-124 TL 263.D17.
Eymuller Helmut
Mann Egon
Stutzle Siegfried
Braun Leslie A.
Levi Benjamin
Zahnradfabrik Friedrichshafen AG
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