US1656458A

US1656458A - Electromagnet construction

Info

Publication number: US1656458A
Application number: US58592A
Authority: US
Inventors: Leo J Wahl
Original assignee: Individual
Current assignee: Individual
Priority date: 1925-09-25
Filing date: 1925-09-25
Publication date: 1928-01-17
Anticipated expiration: 1945-01-17

Description

Filed Sept. 25, 1925 L J WAHL ELECTROMAGNET CONSTRUCTION Jan. 17, 1928.

Patented Jan. 17, 1928.

,UNITED STATES PATENT OFFICE.

LEO J. WAHL, OF STERLING, ILLINOIS.

ELECTBOMAGNET CON STRUGTION.

pers in which the coil of the electro-magnet extends transversely of the casing of the device. In such a device, it is particularly important that the same is so constructed that it will have a minimum width at the portion thereof where it is gripped by the hand of the operator. It is accordingly very important to make the coil and core of the electro-magnet as short as is possible to still obtain the desired amount of power therefrom.

It is particularly a purpose of my inven 1 tion to provide a core for an electro-magnet of this of this character that is so constructed as to provide a better path for the magnetic flux than has previously been the case.

. It is articularly important in a device character to reduce the width of the core portions that lie between theend of the coil and the casing. In order to do this, the thickness thereof is increased to thus obtain substantially the same cross sectional area for the portion of the core lying between the casing and the end of the coil as would be the case if the same were made of a greater width at said portion. This has been previously accomplished by inserting lamiiations in the core that do not extend through the coil, but which extend transversely thereof between the casing and the end of the coil. Preferably, these laminations have end portions that are wider than the transversely extending portions thereof so that icrews or other securing devices can be passed through the same for holding the same in position in the casing. The laminations that extend through the center of the coil are rovided with similar transversely extendmg portions havin similar ends. In the arrangement'with the inserted laminations or added laminations, however, there are numerous air gaps in the path of the flux due to the fact that the flow is partially, in the transversely extending portion of the core, from certain laminations that continue into the center of the coil to the laminations that do not extend into said center.

It is a purpose of my invention to increase the efficiency of the electro-magnet further by eliminating said air gaps. This is accomplished by making the transversely extending portions of the core or the portions lying between the casing and the end of the coil of laminations, all of which continue into the center of the coil. In order to at the same time obtain the desired narrowness and thickness of this portion of the core, I bend the laminations in the portion of the core extending transversely of the coil at an angle, preferably a right angle, to the portions thereof extending through the center of the coil in the form shown herein to obtain the desired amount of iron in the core at this point.

Other objects and advantages of the invention will appear as the description of the accompanying drawings proceeds. However, I desire to have it distinctly understood that I do not intend to limit myself to the exact details shown or described, but that I intend to include as part of my invention all such obvious changes and modifica tions of parts as would occur to a person skilled in this art and as would fall within the scope of the claims.

In the drawings:

Fig. 1 is a view partly in vertical section and partly in elevation of an electro-magnetic clipper embodying my invention;

Fig. 2 is a plan view thereof showing the major portion of the cover broken away and taken substantially on the line 22 of Fig. 1;

Fig. 3 is a section taken on the line 33 of Fig. 1; and

Fig. 4 is a perspective view of one of the laminations.

Referring in detail to the drawings, my invention is shown as being applied to a clipper having a casing comprising the main body portion 10 and the cover 11, the cover being held in place on the main body portion by any suitable fastening means such as those indicated by the numeral 12 in Fig. 2. The main body portion 10 of the casing is provided with a pair of upwardly extending lugs or bossesvl3 for supporting the electromagnet comprising the coil 14: on said casing.

The coil 14 is wound on a core comprising a central main core portion 15 lying within and extending through the coil 14, a portion 16 extending transversely of the coil and portions 17 that. lie on opposite sides of the coil 14 and extend substantially parallel to the central core portion 15. The transverse 1y extending portion 16, it will be noted, is quite narrow as compared to the ends 17 and hes between the side wall 18 of the casing and the end of the coil 15 adjacent thereto, the other side wall being indicated by the numeral 19 in Fig. 2. The end portions 17 are made wider in order to provide suflicient material for extending the fastening means 20 through the same. While the portions 16 are made narrow in order to reduce the width of the casing between the walls 18 and 19 as much as possible and yet get as long a coil between said walls as is possible without increasing the distance between said walls, the portion 16 is furthermore thickened in order to provide a greater amount of material in the portions of the core extending transversely of the coil than would be possible, if the same were made an thicker-than the central portion 15 thereo In order to obtain the desired shape to the core with the thickened transversely extending portion and yet have the magnetic flux travel through the iron throughout the length of the core without passlng acrossany air gaps, the laminations are made as shown more clearly in Figs. 3 and 4.

Referring to Fig. 4, it will be seen that each lamination comprises a central core formin portion 21 and cars 22 lying in substantia y the same plane as the central core forming portion 21 to provide the ends 17 for the core. A transversely extending portion 23 connects the ends or ears 22 0 each lamination with the central portion 21. Said transversely extending portion is bent or flanged as indicated at 24 to provide a portion extendingat an angle to the ends 22 and the central portion 21 lying preferably. in a plane substantially at right angles to the plane of the

portions

21 and 22. Preferably, the blanks are made substantially alike and are bent over or flanged after being assembled, the blanks being-held in proper relation by any suitable means so as not to shift relative to each other. This causes the flanges 23 to have a stepped formation, such Cooperating with the electro-magnet 1s a vibratory armature 26 carrying a movable clipper blade 27 which cooperates with a stationary blade 28 in a well known manner. The armature 26 is offset inwardly at 29 and 30 so as to have the said

portions

29 and 30 thereof lie near the ends 17 of the core, thus having an ofiset to accommodate the coil and core of the electro-magnet. Said vibratory member is preferably clamped in position by suitable clamping means 31 and is vibrated by alternating current passing through the electro-magnet in a well known manner.

Having thus described my invention, what I desire to claim and secure by United States Letters Patent is:

1. In a device of the character described, a casing, an} 'ele'ctrormagnet having a coil lying transversely of said casing and a core in said coil having a portion lying between the endyof said coil and said casing, said core comprising laminations having portions extending at an angle to the axis of said coil lying between said casing and said coil.

2. In a device of the character described, a casing, an electro-magnet having a coil lying transversely of said casing and a core in said coil having a portion lying between the end of said coil and said casing, said core being laminated, and the ortion thereof lying between the end of sai coil and said casing projecting transversely of said coil beyond the portion thereof in said coil, all the laminations of said core externally of said coil extending into said coil.

a casing, an electro-magnet having a coil lying transversely of said casing and a core in said coil having a portion lying between the end of said coil and said casing, said core comprising laminations having portions extending substantially parallel to the axis of said coil and portions extending substantially perpendicularly to'said axis lying between said casing and said coil.

4. In an electro-magnet, a core comprising laminations having flanges thereon extending. transversely of said core, said flanges having projections at the ends thereof extending parallel to and in the planes of said laminatio'ns;

5. In a device of the character described, a casing, an electro-magnet having a coil lying transversely of said casing and a core in said coil, said core comprising laminations' having flat portions within said coil extending substantially parallel to the axis thereof and portions lying between said casing and said coil extending tothe periphery of said coil, said casing and core having cooperating means thereon holding said coil in position transversely of and in spaced relation to said casing.

6. In a device of the character-described,

a casing, a pair of spaced supportstherein, an electro-magnet having a coil between said mamas 3 supports and a core in said coil, said core having oppositely directed portions extending outwardly be 0nd the Cperipher of said c011 at one end t ereof an secure to said supports.

7 In a device of the character described, a casing, a pair of spaced supports therein, an electro-magnet having a coil between said supports and a core in said coil, said core comprising laminations having portions inside said coil extending substantlally parallel to the axis thereof, portions outside said coil secured to said supports and intermediate portions extending transversely of said coil at one end thereof connecting said inside and outside portions.

8. In a device of the character described,

a casing, a pair of spaced supports therein, an electro-magnet having a C011 between said supports and a core in said coil, said core comprising laminations having portions inside said coil extending substantially parallel to the axis thereof, portions outside said coil secured to said supports and intermediate portions extending transversely of said coil at one end thereof connecting said inside and outside portions, said intermediate portions being bent substantially right angles to the lane of said inside portions.

In witness whereof, I hereunto subscribe my name this th day of September, A. D. 1925.

\ LEO J. WAHL.