Machine element or mechanism – Elements – Gear casings
Patent
1982-02-23
1984-09-18
Herrmann, Allan D.
Machine element or mechanism
Elements
Gear casings
74572, 60718, 180165, F16H 4704, G05G 300, F01K 2300
Patent
active
044716680
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Technical Field
The invention concerns a drive assembly that is intended especially for motor vehicles. The drive assembly has a prime mover or engine, a flywheel, and a continuously variable transmission with a first and second connection (11 and 12). The drive assembly also has a driven shaft, intermediate gearing, and four clutches, gearing, shaft.
2. State of the Art
Such a drive assembly is known from German Offenlegungsschrift No. 2 710 532 (corresponding to U.S. Pat. No. 4,126,200). In FIG. 1 of that document the prime mover is designated 10, the flywheel 17, the continuously variable transmission 15 and the drive shaft 31. The intermediate gearing consists of gear wheels 35, 40, and 39. Variable transmission 15 is coupled to both prime mover 10 and intermediate gearing 35, 40, and 39. The four clutches referred to above are made up of the components 37 and 42, 42 and 39, 33 and 44, and 35 and 44. Possible gearing states include
(1) an initial operating range (with clutches 37+42 and 35+44 engaged) in which the sum of the outputs from the prime mover and from the flywheel is transmitted through the continuously variable transmission and
(2) a subsequent operating range (with clutches 39+42 and 33+44 engaged) in which only the output from the flywheel is transmitted through the continuously variable transmission, with that from the prime mover transferred directly, and hence with practically no loss, to the drive shaft.
Page 29, paragraph 2 of the Offenlegungsschrift says that, although different types of continuously variable transmissions can be employed in the device, the power-distributing hydrostatic transmission described on pages 385 to 391 of the journal Olhydraulik und Pneumatik, 1971 is to be preferred. The advantage of this type of transmission over other continuously variable mechanisms is that one component of the output can be transmitted purely mechanically to improve efficiency. The hydraulic component of the power of the transmission is, except immediately after starting, relatively low.
The rotating housing employed in power-distributing hydrostatic transmissions, however, makes them relatively expensive. Another problem is that they are often relatively long overall. Still another drawback is that the mechanical coupling of the two hydrostatic units over a common rotating housing makes it impossible to optimize either of them alone with respect to maximal speed or minimal specific volume.
The known drive assembly shifts from the initial operating range to the subsequent operating range when the speed ratio of the hydrostatic transmission exceeds 1. The range in which the hydraulic power component of the power-distributing hydrostatic transmission is relatively low can thus be increased even further. The speed ratios of the significant drive components can, according to page 33 of the Offenlegungsschrift, also be adjusted to the transmission ratio of the hydrostatic device at the changeover point by dimensioning gear wheels 33, 35, and 37 to 40 appropriately so that the mechanism will shift from the initial operating range to the subsequent range (or vice versa) without relative speeds at the clutches. One disadvantage however is that a relatively large number of wheel gears, usually three or four, is required. It is also impossible to regulate power distribution directly because its continuing operation depends as mentioned above on the transmission ratio at the changeover point. To exploit the hydrostatic transmission to fullest advantage this ratio must be more or less maximal. Any alteration in the curve of power distribution will usually result in an alteration in the maximal volumetric delivery of the hydrostatic transmission, which will simultaneously necessitate an alteration in the transmission ratio of the wheel drive.
THE PROBLEM AND ITS SOLUTION IN ACCORDANCE WITH THE INVENTION
The object of the invention is to improve the drive assembly described in the introduction in such a way that the simplest possible continuously variable transmi
REFERENCES:
patent: 2803151 (1957-08-01), Clerk
patent: 3485037 (1969-12-01), Clerk
patent: 3641843 (1972-02-01), Lemmens
patent: 3665788 (1972-05-01), Nyman
patent: 3749194 (1973-07-01), Bardwick
patent: 3870116 (1975-03-01), Seliber
patent: 4110982 (1978-09-01), Regar
patent: 4126200 (1978-11-01), Miller et al.
patent: 4184385 (1980-01-01), Maeda
patent: 4232568 (1980-11-01), Maeda
patent: 4306467 (1981-12-01), Pollman
Dr.-Ing. Helmar Strauch, "Axialkolben-Umlaufgetriebe", Olhydraulik und Pneumatik 15, (1971), No. 9, pp. 385-391.
Herrmann Allan D.
Voith Getriebe KG
Wojciechowski Bruce F.
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