Machine element or mechanism – Elements – Gear casings
Patent
1995-10-27
1997-11-04
Luong, Vinh T.
Machine element or mechanism
Elements
Gear casings
74417, F16H 5702
Patent
active
056827997
DESCRIPTION:
BRIEF SUMMARY
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a national phase of PCT/GB 94/00004 filed 28 Apr. 1994 and based, in turn, upon Bulgarian national application 97677 of 28 Apr. 1993 under the International Convention.
FIELD OF THE INVENTION
This invention relates to an improved external cylindrical gearing, e.g. for use in gearboxes, and, more particularly, in gear drives of prime movers and all kinds of processing machines.
DESCRIPTION OF THE PRIOR ART
An enclosed bearing facilitates manufacture of gear boxes and the like. As an example, consider the facilitated assembly and disassembly of a reduction gear box having a case receiving bearings, gear-wheels and shafts. The fabrication of the split case, however, is both labor-intensive and expensive. With enclosed bearings, used particularly in machine tools and automobile transmission gears, the case can be of a nonsplit type and inexpensive to manufacture but assembly and disassembly of the gear-wheels and bearings within the case can be a limitation.
A construction of a two-stage (two-speed) gear box meeting stringent limited-noise requirements is well known, this gearbox being built with a split case and having helical gears with parallel axes only, the reducing gearing thereof being made with two pairs of gears with reverse directions of the helix angles (i.e. LH runs with RH), see S.U. invention certificate 1,096,421.
The substantial drawback of this reduction gearbox is that, e.g., for a better flood oiling of all mating gears thereof, the gear ratio of gearing-up is accomplished by decreasing the gear ratio of gearing down, and as a consequence, the overall dimensions and the weight of the reducer are increased.
Also, known is a construction of a multipath external cylindrical gearing of the kind in which the power is divided between distinct paths. In a first step the power is partitioned and in a second step the power paths are combined, the gearing having an input pinion stem in engagement with the gear wheels of no less than two of the compound cluster spur gears thereof. The axes of the cluster spur gears are located round the periphery of a cylindrical surface and this surface lies along the axis of the input pinion-stem. The pinions of the cluster spur gears are engaged with a central gear wheel. The central gear wheel is journaled in such a way that it lies along the axis of the pinion stem. The rolling contact bearings are mounted in respective holes (bearing housings) of the case and cover thereof. The bearings support the cluster spur gears, and a friction coupling used to transmit the torque. The coupling serves not only to prevent an overload but more particularly, to gain the relative angular orientation of the rings of the cluster spur gears, in order to make meshing possible. The assembly proper of the bearings and cluster spur gears may be executed from the exterior of the case, see EP 0,271,898.
The above-mentioned gearing design if not free from the limitations for example the disclosed construction is tied up with a specific use and, as consequence, is not suitable for the general case of machine drives. It is impossible to add more stages in order to reach a still higher gear ratio. The gearing design if complicated which is due to the parts used and the respective locations thereof. The pinion stem and axle thereof are not easy to manufacture.
SUMMARY OF THE INVENTION
The external cylindrical gearing of the invention features a nonsplit case (one-piece case), an input pinion stem, an intermediate pinion stem fitted with respective gear wheels, and an output shaft fitted with a final gear wheel thereon. In accordance with the invention, the intermediate pinion stem has two journal necks and is journaled in radial roller bearings. The bearings are supported by the nonsplit case and in two collars on the respective outer races thereof, whereby in nonloaded zones of the bearing housings in the case radial installation slots are provided, each of the slots having a width greater than the maximum diameter of the
REFERENCES:
patent: 4435994 (1984-03-01), Hata et al.
patent: 5095767 (1992-03-01), Spridco et al.
patent: 5099715 (1992-03-01), Baiker
patent: 5193501 (1993-03-01), Klejeski et al.
patent: 5245883 (1993-09-01), Min
patent: 5291801 (1994-03-01), Hanada et al.
patent: 5375479 (1994-12-01), Kouno et al.
patent: 5404772 (1995-04-01), Jester
patent: 5501117 (1996-03-01), Mensing et al.
patent: 5505101 (1996-04-01), Curtis
Dubno Herbert
Luong Vinh T.
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