Electrical generator or motor structure – Dynamoelectric – Rotary
Patent
1980-01-03
1983-11-15
Skudy, R.
Electrical generator or motor structure
Dynamoelectric
Rotary
310 42, 310 58, 310 91, 310254, 29596, H02K 500
Patent
active
044158246
DESCRIPTION:
BRIEF SUMMARY
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to a stator casing for air-cooled electrical machines, comprising a sheet metal jacket to be placed on the stator core which has a plurality of shaped-on, axially extending, radially projecting and peripherally spaced cooling ribs.
Such a casing is already known from Swiss Pat. No. 92,809 but in this design it has been found that the sheet metal jacket used therein must be made slightly axially longer than the stator core. The jacket thus extends axially, on either side a casing part in addition to the non-supporting sheet metal jacket, which only serves a cooling function.
With the arrival of new technology in which the cast metal casing parts can be directly replaced by an extended sheet metal cooling rib jacket. The new jacket, however, has to be wholly or partly self-supporting, in addition to exercising its cooling function. Such constructions, for example Swiss Pat. No. 337,226 or West German Offenlegungsschrift No. 2,233,860 are connected by means of complicated and costly welds to the stator core surface in order to obtain the necessary surface termination or dissipation of heat and the transfer of forces.
SUMMARY OF THE INVENTION
The problem to be overcome by the present invention is to again wholly or partly move away from the welding technology and to return to the previously described pressing-in technology, while avoiding the disadvantages thereof and while fulfilling the requirements of having the stator casing being self-supporting and with completely satisfactory and uniform heat transfer over the entire contact surface area between core and casing.
According to the invention, this is achieved in that the inner surface of the sheet metal jacket is made axially convex and the inner edge diameters at both ends of the sheet metal jacket preferably correspond to the outside diameter of the associated stator core and that, at both ends, the sheet metal jacket has reinforcements which prevent an enlargement of the edge diameter when the stator core is pressed into the jacket.
As a result of these measures, it is now possible that with the stator core pressed into the stator casing the inner surface of the jacket parts of the stator casing located between the cooling ribs is uniformly and firmly mounted on the stator core by means of its complete square dimensions that stator casing and stator core substantially form a single unit, in which an optimum heat transfer is ensured and the stator casing completely fulfils the requirement of then being self-supporting.
The convex construction of the stator casing represents an initial stressing which, on pressing in the stator core ensures that the stator casing exerts on the stator core an adequate contact pressure, which is uniformly distributed over the complete square dimensions of contact.
The reinforcements located close to the edges and which prevent an enlargement of the internal edge diameter of the stator casing on pressing in the stator core can be external and/or internal thrust rings, which are connected to the sheet metal jacket in the vicinity of the edge, e.g. by means of welds. These thrust rings can then serve as supports for the bearing brackets of the machine.
However, it is also possible for the reinforcements to be formed by welded joints, close to the edges, on the base of the cooling ribs.
The present invention also relates to a use of the stator casing according to the invention on an air-cooled electrical machine, characterised in that the stator casing is pressed onto the stator core in such a way that the inner surface of the jacket parts located between the cooling ribs is mounted so uniformly and firmly on the stator core by the complete square dimensions thereof that stator casing and stator core, at least from the heat and force transfer standpoints substantially form a constructional unit.
According to a preferred development, an additional, axially extending keyed joint is provided between stator casing and stator core for producing a radial form-loc
REFERENCES:
patent: 1884573 (1932-10-01), Chapman
patent: 2761984 (1956-09-01), Adam
patent: 2795713 (1957-06-01), Woll
patent: 3229130 (1966-01-01), Drovard
patent: 3749949 (1973-07-01), Muller
patent: 3870909 (1975-03-01), Pangburn
patent: 4103192 (1978-07-01), Wendt
patent: 4244098 (1981-01-01), Barcus
Skudy R.
Zschokke Wartmann AG
LandOfFree
Stator casing for air-cooled electrical machines does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Stator casing for air-cooled electrical machines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stator casing for air-cooled electrical machines will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-161221