US2582866A - Magnetoelectric machine - Google Patents

Description

Jan. l5, 1952 P. HARscH ErAL 2,582,866

MAGNETOELECTRIC MACHINE Filed April 7, 1949 2 SHEETS-SHEET 1 rigs mmemm P. HARSCH TAL MAGNETOELECTRIC MACHINE Jan. l5, 1952 2 SHEETS-SHEET 2 Filed April 7, 1949 me ffm/@41M Md M 11n-Maw? Patented Jan. 15, 1952 MAGNETOELECTRIC MACHINE Paul Harsch, Nurnberg-Eibach, Bavaria, and

Franz Rinkel, Nurnberg, Bavaria, Germany, assignors to Firma Noris Zund-Licht, Aktiengesellschaft, Bavaria, Germany Application April 7, 1949, Serial No. 85,966

In Germany November 6, 1948 8 Claims.

Lighting dynamos of this type for internal combustion engines are known in which a system consisting of permanent magnets rotates about one or more coils.- The rotatory magnet system was originally constructed in such a way that at first two bar magnets were bent and provided with pole shoes. These magnets were accommodated in a casing of a non-magnetizable material. This design resulted from the fact that the chromium and cobalt steels used in the beginning of the development of these devices had a relatively small coercitive force. When high-quality material for magnets became available, the magnets could be gradually reduced in size and a greater number of magnets could be accommodated on the same circumference. However, a casing of a non-magnetizable material consisting of brass, bronze, aluminum castings or the like continued to be used for the magnets.

This arrangement has the disadvantage that the total weight is relatively high. for a given flywheel moment. Another drawback of the said arrangements consists in that owing to the relatively low tearing strength of the alloys used for the casing the danger of an explosion of the aggregate existed if the internal combusion engine by any chance was operating with excessive speed. Such explosions actually did happen in practice. Therefore, the manufacturers were compelled to specify a maximum speed.

Since the rotatory magnetic system with its carrier simultaneously served as a flywheel for the internal combustion engine, it was oftentimes Tnecessary to accommodate the magnetic system with its non-magnetic armoring in an iron casing. In this case, it was necessary, however, to provide a certain distance from the magnet in order that the lines of magnetic force were not deflected.

Finally, the machines also have to be protected against dirt and water; to this end in the previous types a protective cap of a nonamagnetizable material had to be provided, whereby the manufacturing costs, of course, were increased.

It is the object of the present invention to provide a design by'which all the said disadvantages of the known designs with non-magnetic casing are avoided.

Further objects of the invention will appear as the specification proceeds.

According to the invention a magnetic material closing the outer magnetic circuit between the single magnets is used as a carrier for the magnet. More particularly, iron is used for this purpose. The magnets are radially disposed on their carrier so that contrary to the existing types the lines of magnetic force in the magnet run approximately parallel to the radius passing through the centre of the magnet, while the magnetic ux in the know types followed approximately the direction of the circumference in the bent magnets. A further advantage of the system according to the invention resides in the fact that the magnets can be produced as simple prismatic bodies which engage the carrier and possibly the pole shoes with a relatively large base surface.

The magnets may be either provided with separate pole shoes or their head portion itself may be formed as a pole shoe. In the first case the pole shoes may consist of flat iron while it had been necessary so far to make them of high quality dynamo sheets. The pole shoes may be provided with steps so that the adjustment of the ignition moment is facilitated without requiring any turning of the coil system. The pole shoes or the magnets respectively are advantageously secured to the carrier with the aid of fixing means of a non-magnetic material, e. g., by brass pins, so as to avoid any magnetic connection from the pole shoe or its inner pole surface to the carrier. Owing to its construction from a magnetic material, more particularly iron, the carrier can be drawn in the form of a pot and may consist of an integral piece with the hub, whereby the machining operations and parts so far required for fixing the hub can be dispensed with. It is also possible to weld the hub directly to the casing while this was impossible, for reasons of mechanical strength, with the materials used so far.

Very frequently it is necessary to ilt the lighting dynamo into the blower wheel serving for cooling the internal combustion engine. According to the invention the casing or carrier for the permanent magnets may be formed as an iron ring in this case also and accommodated in the blower wheel. By this design the whole expensive construction of the blower wheel of a non-magnetizable material and the additional flywheel masses which had to be'spaced by a considerable distance from the magnet can be dispensed with. The use of iron for the blower wheel caused a reduced eiciency in the previous designs unless a larger distance was provided from the edge of the blower to the magnets, with its known disadvantages. Moreover, the magnets may now be accommodated directly in a blower wheel consisting of iron. The protective cap may be made of sheet iron in the same manner.

Further objects and features will be seen from the following detailed description in connection with the accompany-ingI drawingI showing by way of example and'purely schematically some embodiments of the invention and in which:

Fig. 1 is an axial section through a lighting ma.- chine,

Fig. 2 is a front view of the permanent mag'- net system of Fig. 1, the coil'sand the cores thereof being indicated by dottedzlines,

Fig. 3 is an axial section through a'A magnetic system in which the carrier consists of a ring,

Fig. 4 is a front View of a magnetwhichisin-` serted in an annular carrier and whose-head-face is in itself formed as a pole shoe,

Fig. 5 is a partial view same as FigA; show.- ing a stepped pole shoe for the adjustment of different ignition times,

Fig. Gis a section through a lighting machine with dust cap and fan blades, andr Figi. 7 isa partial viewlof'Fig. 6.

Similar reference numerals denote similar partsfin the different V-iews.

Referring now tothe drawings ingr-eater detail, it` will be seen that the magnets are shown at I, four suchmagnetsbeing provided according to Fig. 2;

Thesemagnets, consisting of 'high quality magnet alloys,- e. g. of a nickel, aluminum, iron. alloy with small additions of cobalt, chromium or tungsten, or of iron, nickel, cobaltl andv titanium, aresecured withy theirY endface'2 to theerimf 3` ofa-pot-shaped casing 4, e. g. of iron whichmay be'formed integral with the hubV 5, a set of coils ii. being provided inside said casing in known manner. llhe whole system is covered by'a cap 'Lofr magnetic material.

In the embodiment as per Fig. 3 the magnets Iiv arey built into an annular.` carrier 8.v which is` inserted in the casingY 9 of-magnetizable material.

In the embodiments according to. Figs;.11to.3.

pole shoes IE which according to the invention fz may consist of vflat liron are attachedto` the inner end faces of f the magnets .andi the magnets'. arey held by means of fixing pins II consisting of 1a non-magnetizable material, e. g., of brass..

As shown-in Fig; 4, the 'polefsurface I2iof..the. magnets- I- canbe'designed'in suchra' way that' additional -pole shoesmay-be dispensedfwith.

Moreover, as shownin Fig..5,vv itiisxpossible'stov provide the -poleshoes with -steps 1 I 3"in.sich a way. that two breaking-edges I4 andl |51A are-formed whichA render it possibleI in known mannen to adjust the ignitiontime withoutreadjusting .the coil plate, possibly by means-of automatic adjustment of the breaking cam or by readjustment' of the break.

Inthe embodimentras perligs.` andv` 'y fan blades I6 also consistingfof'iron orl the'likeand forming the blower wheel'serving forcooling. the. motor are vprovided on the casingli;`A In this case it is possible-to usethev blowery wheellitselfiasxai carrier vforv thepermanent magnet. This `figure also shows how the hub 5'is welded into .the casing. dat-I1.

Asyariouspossible embodiments might bemande ofthe above invention, and aszvarious. changes.

might be made in the embodiments. ab'ovefsetY forth, it isV tov be understood that. all matter: herein set forth or. shown in the accompanying., drawing isi-to be interpretedas.r illustrative.y and'Y not in a limiting sense;

Having thus described our invention, we claim as new and desire to secure by Letters Patent:

1. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magnetic material and having a hub; a plurality of permanentmagnets having` center lines radially disposed and arranged ina symmetrical conguration in said carrier with respect to said hub and with equal distances therefrom; and at least. one coil. arranged between said hub and said magnets and having a magnetic core arranged with. the axis.v thereof at any moment at rig-htv angles. to` one of the radial directions from said hub'to said carrier, whereby the magnetic circuit extends from said magnetic carrier throughfcnefof: said magnets substantially parallelitotheecenter line thereof, said core of said coil, and another of said magnets substantially parallel' to the center line thereof and back to said magnetic carrier.

2. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magnetic material and having a hub; a plurality "of permanent magnets having center lines radially'disposed and arranged with-the axes thereof infradial directions, respectively, and inI symmetrical coniigurationinlsaid carrier with respect-to saidhub and with equal distances therefrom, said magnets being in direct contact with said carrier; and at leastv one'coil arrangedbetween said hub and said magnets and having s. magnetic core arranged with the axis-thereof at any momentat right angles to one ofthe radial directions from said hub -to saidicarrier, whereby the'magnetic circuit extends from saidmagnetic carrier through one of said magnetsv substantially parallel to thecenter line thereof, said core ofsaid'coil, and another of said magnets substantially parallel to the center line thereof Aand'backl i; to said magnetic carrier.

3'. A- magneto-electric machinev comprising in combination, al rotatable carrier consisting of magnetic material and having a hub; a plurality of 'permanentmagnets-having`center lines radially disposed andy arranged in a` symmetrical conguration'in said carrierwithsrespect to Vsaid hub and'withequaldistances therefrom; aplurality of ironpole shoes' secured to said magnets, respectively, and having'- part-cylindrical surfaces arranged symmetricallyiaboutsaid hub;

and=at least one coi-l arranged-between said hub and said` pole-A shoes of saidfmagnets andhavinga magneticA core arranged with the axisv thereof atany-v moment at right angles to-one of; the radial directions-from said hub to said carrier, wherebyV thel magnetic circuit extends from saidmagneticcarrierthrough one of said magnets substantially "parallel tothe center line thereof; said core-of saidlcoil, and anotherA of saidmagnets substantially parallel to the'center iine thereof and back tosaidimagnetic carrier'.

4. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magneticY material Tandv havinga hub; a4 plurality of permanentmagnets having center lines radially dis'posed'and .arranged .ina symmetrical congurationinsaid carrier. with .respectto said hub and with equal distances therefrom a plurality of f iron polefshoes securedfto saidmagnets and formingA the head1 portions thereof, respectively, and having part-cylindrical surfaces: arranged symmetrically about saidphub; andsat least one coil arranged between said huband said. pole` shoes.; of saidmagnets: and` having a magnetic core arranged with the axis thereof at any moment at right angles to one of the radial directions from said hub to said carrier, whereby the magnetic circuit extends from said magnetic carrier through one of said magnets substantially parallel te the center line thereof, said core of said coil, and another of said magnets substantially parallel to the center line thereof and baci: to said magnetic carrier.

5. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magnetic material and having a hub; a plurality of permanent magnets having center lines radially disposed and arranged in a symmetrical configuration in said carrier with respect to said hub and with equal distances therefrom; a plurality of iron pole shoes secured to said magnets, respectively, and having part-cylindrical surfaces arranged symmetrically about said hub; at least one coil arranged between said hub and said pole shoes of said magnets and having a magnetic core arranged with the axis thereof at any moment at right angles to one of the radial directions from said hub to said carrier, whereby the magnetic circuit extends from said magnetic carrier through one of said magnets substantially parallel to the center line thereof, said core of said coil, and another of said magnets substantially parallel to the een ter line thereof and back to said magnetic carrier; and steps formed in said part-cylindrical surfaces of said pole shoes, said steps facilitating the change of the magnetic flux in said core when said magnets rotate.

6. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magnetic material and having a hub; a plurality of permanent magnets having center lines radially disposed and arranged in a symmetrical configuration in said carrier with respect to said hub and with equal distances therefrom; at least one coil arranged between said hub and said magnets and having a magnetic core arranged with the axis thereof at any moment at right angles to one of the radial directions from said hub to said carrier, whereby the magnetic circuit extends from said magnetic carrier through one of said magnets substantially parallel to the center line thereof, said core of said coil, and another of said magnets substantially parallel to the center line thereof and back to said magnetic carrier; and an end plate arranged on said carrier and forming a flywheel mass associated with said carrier.

7. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magnetic material and having a hub; a plurality of permanent magnets having center lines radially disposed and arranged in a symmetrical configuration in said carrier with respect to said hub and with equal distances therefrom; at least one coil arranged between said hub and said magnets and having a magnetic core arranged with the axis thereof at any moment at right angles to one of the radial directions from said hub to said carrier, whereby the magnetic circuit extends from said magnetic carrier through one of said magnets substantially parallel to the center line thereof, said core of said coil, and another of magnets substantially parallel to the center line thereof and back to said magnetic carrier; and an end plate arranged on said carrier and forming a ilywheel mass associated with said carrier and including a plurality of fan blades.

8. A magneto-electric machine comprising in combination, a rotatable carrier consisting of magnetic material and having a hub; a plurality of permanent magnets having center lines radially disposed and arranged in a symmetrical configuration in said carrier with respect to said hub and with equal distances therefrom; at least one coil arranged between said hub and said magnets and having a magnetic core arranged with the axis thereof at any moment at right angles to one of the radial directions from said hub to said carrier, whereby the magnetic circuit extends from said magnetic carrier through one of said magnets substantially parallel to the center line thereof, said core of said coil, and another of said magnets substantially parallel to the center line thereof and back to said magnetic carrier; and a protective cap consisting of a drawn sheet metal body and arranged so as to cover said carrier and said magnets.

PAUL HARSCH. FRANZ RINKEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,810,844 Morel June 16, 1931 2,104,707 Rawlings Jan. 4, 1938 2,446,761 Harmon Aug. 10, 1948 2,458,336 Brownley Jan. 4, 1949 2,462,761 Momberg Feb. 22, 1949 2,469,196 Goldberg May 3, 1949 2,472,313 Phelon June 7, 1949

Images