US3548353A

US3548353A - Actuating magnet of flat construction

Info

Publication number: US3548353A
Application number: US751869A
Authority: US
Inventors: Edmund Bausch
Original assignee: Binder Magnete GmbH
Current assignee: Binder Magnete GmbH
Priority date: 1967-08-11
Filing date: 1968-08-12
Publication date: 1970-12-15
Anticipated expiration: 1987-12-15
Also published as: FR1575302A; GB1232446A

Description

Dec. 15, 1970 E. BAUSCH ACTUATING MAGNET OF FLAT CONSTRUCTION Filed Aug. 12, 1968 Sheets-Sheet 1 III III IIIIL III IIIIIlIIlIlIl-m Fig.2

Fig.1

[N V EN TOR.

Dec. 15, 1970 E. BAUSCH 3,548,353

ACTUATING MAGNET OF FLAT CONSTRUCTION Filed Aug. 12, 1968 3 Sheets-Sheet 2 INVENTOR. Fig. 4

Dec. 15, 1970 BAUSCH 3,548,353

ACTUATING MAGNET OF FLAT CQNSTRUCTION Filed Aug. 12, 1968 3 Sheets-Sheet 5 INVENTOR.

United States Patent 3,548,353 ACTUATING MAGNET OF FLAT CONSTRUCTION Edmund Bausch, Kirchen-Hausen, Germany, assignor to Binder Magnete KG, Villingen, Black Forest, Germany, a corporation of Germany Filed Aug. 12, 1968, Ser. No. 751,869 Claims priority, application Germany, Aug. 11, 1967, 1,589,539 Int. Cl. H01f 7/08 US. Cl. 335-476 8 Claims ABSTRACT OF THE DISCLOSURE Actuating magnet of fiat construction, particularly for ofiice machines, data processing installations and the like, includes an E-shaped core having outer legs surrounded by a respective energizing coil so that the respective ends of the outer legs are located within the respective coil, and a double-armed armature rotatably mounted on the middle leg of the core so that one arm of the armature is displaceable into the interior of one of the coils, and the other arm into the interior of the other coil.

SPECIFICATION My invention relates to an actuating magnet of fiat construction as may be used, for example, for oifice machines, data processing installations and the like.

In addition to the general requirements of the office machine industry for actuating magnets having small overall volume (fiat construction), large numbers of switching operations without requiring maintenance (long life), short switching times and low cost, there has recently arisen the requirement for obtaining, with the smallest possible magnet dimensions, relatively high peak forces at the commencement of the lift or stroke. These peak forces occur, for example, in both directions of a yes-no circuit.

This problem has heretofore been avoided by using a polarized electromagnct having a stroke starting position fixed by a permanent magnet. Such magnets are sluggish in operation, are subject to considerable wear, and provide the required forces only when they have a relatively large overall volume.

It is accordingly an object of my invention to provide an actuaing magnet of extremely small dimensions, having a magnet force-distance characteristic which is adaptable to various problems in the application thereof, for example to a characteristic having high initial peak forces as required in office machines.

With the foregoing and other objects in view, I provide, according to the invention, an E-shaped core, having outer legs that are each surrounded by a respective energizing coil so that the leg ends are located within the coil. On the middle leg of the core there is rotatably mounted a two-armed armature, one of the arms thereof being displaceable into the interior of one coil and the other arm into the interior of the other coil.

In an actuating magnet according to the invention, therefore, two active air gaps are each located respec tively inside an energizing coil and are defined at least partly by the iron core which is formed of laminations of iron plates. By varying the construction of iron plate de- 3,548,353 Patented Dec. 15, 1970 fining these active air gaps, a great variety of magnet force-distance characteristic curves may be produced. The construction according to the invention also provides a very favorable iron circuit with very small inactive air gaps, and the armature is provided with a very small mass. Due to the fact that the armature is rotatably mounted, the magnet force can be taken directly off the armature without the interposition of further structural elements. The magnet force is applicable in various possible directions in the plane of movement of the armature. Purely rotational and purely linear forces and also forces along general curves are capable of being represented. More particularly, it is significant that the magnet forcedistance characteristic is independent of the magnitude of the stroke, i.e. the force-distance characteristic obtained both for strokes larger in comparison with the angle of rotation of the armature as well as for strokes smaller in comparison with that angle is the same as for a normal stroke, since the characteristic is dependent solely upon the magnet system and not upon the location at Which the force is taken from the armature. In addition, the full mechanical energy output of the magnet system is available in each direction of the force and for each stroke. This signifies a particular advantage for short strokes, since even with very short strokes, for example of only a few tenths of a millimeter in length, the full stroke work or energy output and every desired character istic are available, for example also a falling or decreas ing charactertistic. In the case of the heretofore known magnet structures, shortening of the stroke results in a loss of stroke work or energy output. Furthermore, in the heretofore known magnets, a falling or decreasing characteristic can be obtained only with considerably longer strokes. Moreover, with the magnet according to the invention, there is no limitation in the length of stroke, since the initial position of one armature side is fixed by the end position of the other armature side.

The rotatably mounted armature permits the use of the actuating magnet of my invention as a rotary magnet, exactly the same as a linear stroke magnet. In accordance with further features of my invention, by means of a spring or by external forces, one position or both end positions of the armature are set as the zero position, and there is afforded a simple subdivision of the stroke into two diametrical operating ranges. The magnet may thus be used as simple stroke or lift magnet, double and and reversing stroke magnet, hinged armature magnet or double or reversing rotary magnet. The magnet is preferably provided with a symmetrical construction, however, it may also be constructed asymmetrically with regard to the location of the coils, air gaps, core plates, armature and zero position of the armature.

Other features which are considered as characteristic for the invention are set forth inthe appended claims.

Although the invention is illustrated and described herein as embodied in Actuating Magnet of Flat Construction, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of a specific embodiment when read in connection with the accompanying drawings, in which:

FIG. 1 is a plan view, partly broken away and partly in section, of an actuating magnet according to the invention;

FIG. 2 is a view of FIG. 1 taken along the section line IIII in the direction of the arrows;

FIGS. 3a, 3b and 3c are fragmentary perspective views of different embodiments of the core and cover plates at the air gap in the magnet of FIG. 1;

FIG. 4 is a plot diagram of magnetic force-distance characteristic curve, corresponding to the magnet having the modifications shown in FIGS. 3a, 3b and 30;

FIGS. 5a and 5b are diagrammatic views of part of the armature of the magnet shown in FIG. 1 showing a resetting spring therefor connected at different locations thereto.

Referring now to the drawings and first, particularly to FIGS. 1 and 2, there is shown an actuating magnet according to the invention having a movable armature 1, an E-shaped core 3, which may consist of a single plate, as shown in FIG. 2, or of a number of plates, U-shaped cover plates 4 and 5 mounted laterally on the core 3, and energizing

coils

2a and 2b, surrounding the outer legs of the core 3. The armature 1 is rotatably mounted in a bush 6 means of a pin 7 extending between two T-

shaped plates

9 and 10 that are secured to the middle leg of the E-shaped core 3-. One arm 1a of the armature 1 extends into the interior of the coil 2a, and the other arm 1b of the armature extends into the interior of the other coil 2b. When one of the two

energizing coils

2a and 2b is energized, the armature 1 rotates about its bearing pin 7 and the respective end arm of the armature 1 then plunges into the respective coil and abuts against an end face, provided with an adhesion surface 11, of a respective outer leg of the E-shaped core 3.

FIGS. 3a, 3b and 30 show different construction of the core and cover plates of the outer legs of the E-shaped core, the cover plates forming cooperating members for the armature end arms. Depending on the particular configuration shown in FIGS. 3a, 3b or 30 of the core and cover plates in the actuating magnet of my invention, a magnetic force-distance characteristic curve a, c or b is obtained, as shown in FIG. 4. These magnetic force-distance characteristic curves remain constant, independently of the particular stroke of the magnet.

The actuating force may be determined or taken off directly from the armature 1. Several possible ways of doing this are apparent from FIG. 1. Thus, the magnitude and direction of the actuating force may be taken off directly as a linear force, as in the case of a lifting magnet, by means of a diagrammatically illustrated rod 12. Another possible way is to take oif the actuating force as a purely rotational force by way of the shaft or pin 7 bearing the armature l. A third possible way for the direct takeoff of force is to provide the armature 1, either on one or on both sides thereof with a cam surface 13 as shown in broken lines, which cooperates with a roller 14 so that, depending on the shape of this cam surface 13, force can be taken off along a predetermined curve path.

FIGS. 5a and 5b illustrate two practical application of my invention, in which, by means of a tension spring 8, the armature 1 is fixed in zero position either at two initial positions as in the embodiment of FIG. 5a, or at a middle position as in the embodiment of FIG. 5b, when the coils are de-energized. A very great variety of force-distance characteristic curves may be produced thereby.

Since the active air gaps of the magnet are always located within the

coils

2a or 2b, the yoke faces of the core 3 are extremely well protected from dirt, since any dust particles or other contaminating particles, such as iron particles or the like, can at best only reach the surfaces of the yoke or magnet core 3 through the narrow gap located between the armature arms In and 1b and the inner edge of the

respective coils

2a and 2b.

The effective air gap is preferably located in the region of the upper third to the upper half of each coil, as shown in FIGS. 1 and 2.

The armature 1, preferably constructed symmetrically with respect to its axis of rotation extending along the pin 7, is very insensitive to linear vibrations. The bearing 6, concentrated into a relatively small friction surface, ensures a long operating life.

All the parts conducting magnetic flux may be produced, for example, by a stamping operation and can be assembled by welding, adhesion or riveting. A very economical manufacture is thereby assured. The actuating magnet according to the invention may be operated by direct current or alternating current. In the latter case, the lamination plates of the core 3 and/or of the armature 1 should not be too thick and, for example, should be electrically insulated from one another by any suitable means.

I claim:

1. Actuating magnet of flat construction comprising an E-shaped electromagnetic core, having a pair of outer legs and a center leg therebetween, each of said outer legs being flat and having a free end, a cover plate respectively covering the opposite fiat sides of said outer legs and projecting beyond said free end of said outer legs, an energizing coil having a hollow center surrounding each of said plate-covered outer legs of said core, respectively, so that the free end of said outer legs is disposed within the hollow center of the respective coil, and a double-armed armature rotatably mounted on said center leg of said core so that one of the double arms thereof is displaceable into the hollow center of one of said coils and the other of the double arms into the hollow center of the other of said coils and both arms respectively receivable between the projecting cover plates of each of said outer legs and engageable with an end face at the free end of said outer legs, respectively.

2. Actuating magnet according to claim 1, wherein the respective positions of said cover plates project beyond said free ends of said outer legs have given configuration for producing a predetermined magnet forcedistance characteristic curve.

3. Actuating magnet according to claim 1, wherein said core and said cover plates are formed of stampedout metal plates, said metal plates being secured to one another.

4. Actuating magnet according to claim '1 wherein said core and said armature are formed of stamped-out laminations of magnetic flux-conducting metal plates, the laminations of said core and of said armature, respectively, being welded to one another.

5. Actuating magnet according to claim 1 wherein said core and said armature are formed of stamped-out laminations of magnetic flux-conducting metal plates, and layers of adhensive material between said laminations for bonding together the laminations of said core and of said armature, respectively.

6. Actuating magnet according to claim 1 wherein said core and said armature are formed of stamped-out laminations of magnetic flux-conducting metal plates, and rivet means for riveting together the laminations of said core and of said armature respectively.

7. Actuating magnet according to claim 1 wherein said armature is substantially centrally pivoted and including spring means anchored at one end to a point stationary relative to the pivot of said armature and extending transversely to said double arms of said armature over said pivot thereof and secured to said armature at a location thereof beyond said pivot in a direction from said stationary point.

8. Actuating magnet according to claim 1 wherein said armature is substantially centrally pivoted, and including spring means anchored at one end to a point sta- 5 tionary relative to the pivot of said armature and extending transversely to said double arms of said armature toward said pivot thereof and secured to said armature at a location thereof between said stationary point and said pivot.

References Cited UNITED STATES PATENTS 1,315,777 9/1919 King 335-181X 6 1,532,045 3/1925 Davis 335 -181X 1,538,950 5/1925 Price 335-481 2,679,563 5/1954 Katsumata 335268X BERNARD A. GILHEANY, Primary Examiner R. N. ENVALL, JR., Assistant Examiner US. Cl. X.R. 335281