US3930212A

US3930212A - Method of orienting electrically conductive bodies, preferably non-magnetic ones, in a magnetic field and apparatus for performing same

Info

Publication number: US3930212A
Application number: US433885A
Authority: US
Inventors: Benyamin Alexandrovich Ioffe; Robert Karlovich Kalnin; Vyacheslav Semenovich Dorcfeev; Viktor Georgievich Sirotenko; Vladimir Borisovich Larin; Gunar Yanovich Sermons; Alexandr Alexandrov Shevchenko
Original assignee: INST FIZ AN LATVSSR
Current assignee: INST FIZ AN LATVSSR
Priority date: 1968-12-25
Filing date: 1974-01-16
Publication date: 1975-12-30
Anticipated expiration: 1992-12-30

Abstract

A method of orienting electrically conductive bodies, preferably, non-magnetic ones, in a magnetic field, wherein a body is oriented under the action thereupon of a non-uniform magnetic field induced by an alternating electric current, by means of electromagnets connected to an alternating current supply, the pole pieces of these magnets defining therebetween an orientation zone, whereby a body can be oriented both from an arbitrary position and from any intermediate position into a predetermined final spatial position, with the final oriented position of the body being retained.

Description

United States Patent [1 1 Ioffe et al.

[ 1 Dec. 30, 1975 METHOD OF ORIENTING ELECTRICALLY CONDUCTIVE BODIES, PREFERABLY NON-MAGNETIC ONES, IN A MAGNETIC FIELD AND APPARATUS FOR PERFORMING SAME [75] Inventors: Benyamin Alexandrovich Ioffe;

Robert Karlovich Kalnin; Vyacheslav Semenovich Dorcfeev; Viktor Georgievich Sirotenko, all of Riga; Vladimir Borisovich Larin, Smolensk; Gunar Yanovich Sermons; Alexandr Alexandrovich Shevchenko, both of Riga, all of U.S.S.R.

Institut Fiziki Akademii Nauk Latviiskoi SSR, U.S.S.R.

221 Filed: Jan. 16,1974

2| Appl. No.: 433,885

Related US. Application Data [63] Continuation of Ser. No. 885,190, Dec. 15, 1969.

[73] Assignee:

[30] Foreign Application Priority Data Dec. 25, 1968 U.S.S.R 1289054 Dec. 25, 1968 U.S.S.R 1289056 52 U.S.Cl. ..33s/2s4;33s/250;335/2s1; 335/282; 335/299 51 lnt.Cl. ..H01F 7/20 [58] Field of Search 335/229, 234, 250, 281,

[56] References Cited UNITED STATES PATENTS 698,024 4/1902 Knapp 335/234 2,400,869 5/1946 Lovell 335/250 V 3,054,026 9/1962 Lovell 335/250 FOREIGN PATENTS OR APPLlCATlONS 181,481 10/1964 U.S.S.R 335/229 Primary ExaminerJ. D. Miller Assistant ExaminerFred E. Bell Attorney, Agent, or FirmHaseltine, Lake & Waters [57] ABSTRACT A method of orienting electrically conductive bodies, preferably, non-magnetic ones, in a magnetic field, wherein a body is oriented under the action thereupon of a non-uniform magnetic field induced by an alternating electric current, by means of electromagnets connected to an alternating current supply, the pole pieces of these magnets defining therebetween an orientation zone, whereby a body can be oriented both from an arbitrary position and from any intermediate position into a predetermined final spatial position, with the final oriented position of the body being retained.

1 Claim, 9 Drawing Figures U. S Patent Dec 30, 1975 Sheet 1 0f 5 3,930,212

US. Patent Dec.301975 Sheet2of5 3,930,212

US. Patent Dec.30, 1975 Sheet3of5 3,930,212

US. Patent Dec. 30, 1975 Sheet40f5 3,930,212

U.S. Patent Dec.30, 1975 shws 0f5 3,930,212

METHOD OF ORIENTING ELECTRICALLY CONDUCTIVE BODIES, PREFERABLY NON-MAGNETIC ONES, IN A MAGNETIC FIELD AND APPARATUS FOR PERFORMING SAME This case is a continuation of application 885,190, filed Dec. 15, 1969.

The present invention relates to a method of orienting electrically conductive bodies, including, non-magnetic ones, in a magnetic field and to and is useful in various industries in which electrically conductive bodies are to be oriented for further treatment. The invention can be widely used for introducing automation into processes which various articles and workpieces are to be oriented in the course of their being manufactured or assembled into units, machines, apparatus, and so forth A method of orienting electrically conductive bodies is known, according to which the orientation operation is performed due to an interaction of the magnetic field of a permanent magnet with alternating electric currents induced in the bodies being oriented.

This known method, however, provides merely for orienting successive bodies or workpieces from an arbitrary position into a single predetermined intermediate position, and does not provide for orienting a body into a desired final position both from an arbitrary position and from any intermediate position, depending on a characteristic feature of said body, e.g., a projection, an aperture, a groove or slit in one of the sides of the body, a structural difference between the portions of the body, and so forth. Additionally this known method is incapable of retaining the bodies being oriented in a desired position, which is essential for the majority of production processes.

It is an object of the present invention to overcome the disadvantages of the known method.

The present invention has as a more specific object the provision of a method of orienting electrically conductive bodies, including non-magnetic ones, in a magnetic field, and of apparatus for performing the same which method should provide for a bodys being simultaneously oriented and retained in an oriented position, relative to two or more perpendicular reference planes, This method should further provide for simple and efficient control of the parameters of the magnetic field created in the zone where said bodies are oriented, and should additionally provide for either simultaneous orientation of several streams of successive bodies, or for orienting successively supplied bodies under the action of different types of non-uniformity of a magnetic field, as these bodies are falling through a plurality of serially arranged magnetic systems.

According to the present invention, a method is provided for orienting electrically conductive bodies wherein a body is oriented under the action of a nonuniform magnetic field induced by an alternating electric current, a inductance of said field decreasing in a direction toward the central portion of the orientation zone.

It is advantageous for the frequency of said alternating electric current inducing said magnetic field to be selected in accordance with a predetermined ratio of the inductive reactance to the resistance of said body being oriented.

A method, embodying the present invention, may be performed by the following types of apparatus:

an apparatus comprising at least one electromagnet having a winding adapted to be connected to an alternating current supply source and a magnetic core including at least one pair of pole pieces defining therebetween an orientation zone, said pole pieces beinig shaped and arranged relative to each other to create a non-uniform magnetic field of which the inductance decreases toward the central portion of said orientation zone; each one of said pole pieces preferably having at least one V-shaped cut facing said orientation zone;

an apparatus comprising at least two electromagnets, each including a C-shaped magnetic core, said respective magnetic cores being adjustably mounted for selective positioning thereof relative to one another, each one of said electromagnets being adapted to be connected to a source of alternating electric current of adjustable frequency;

an apparatus comprising an electromagnet including a plurality of generally C-shaped magnetic cores, all of said magnetic cores being associated with a pair of pole pieces the first one of said pair of pole pieces being disposed above the second one of said pair of pole pieces, said first pole piece having at least one passage therethrough through which a body can be introduced into an orientation zone, said second pole piece having at least one aperture therethrough through which a body can leave said orientation zone after the orientation operation.

In a further modification of the last-mentioned type of apparatus, the magnetic core assembly may be a multi-level one, having a respective pole piece at each of the levels thereof, all of said apertured pole pieces being preferably shaped as truncated pyramids, the small bases of said truncated pyramids of the adjacent ones of said pole pieces facing each other, the crosssectional shape of each one of said apertures through which a body can leave said orientation zone corresponding to the contour of said body in a plan view.

The herein disclosed method of orienting electrically conductive bodies in a magnetic field and the apparatus performing same have been found to attain successfully the above specified aims and objects.

The present invention will be better understood from the following detailed description of some of the preferred embodiments of a method of orienting electrically conductive bodies in a magnetic field, as well as of several embodiments of apparatus for performing the same, with due reference being had to the accompanying drawings, wherein:

FIG. 1 shows schematically and in perspective a general view of an apparatus, embodying the invention, with pole pieces having a V-shaped cutaway portion;

FIG. 2 illustrates the distribution of magnetic flux in the space between the pole pieces and indicates the forces acting upon a body in the respective areas of the orientation zone;

FIG. 3 shows in detail the pole pieces of an apparatus, according to FIG. 1, having their respective V- shaped cuts slanting relative to a vertical plane, defining an orientation zone which flares up wardly;

FIG. 4 shows in detail the pole pieces of an apparatus, as shown in FIG. 1, each of the pole pieces having a pair of adjacent V-shaped cuts;

FIG. 5 shows an apparatus, embodying the invention, having a pair of electromagnets, each with a Cshaped magnetic core;

FIG. 6 shows a structure wherein a plurality of apparatus of the kind shown in FIG. are mounted for relative adjustable positioning;

FIG. 7 shows the general view of an apparatus, embodying the invention, including an electromagnet with a plurality of individual C-shaped magnetic cores associated with a single pair of pole pieces, adapted for orienting a single stream of successive bodies;

FIG. 8 shows a view similar to that in FIG. 7, with pole pieces adapted for orienting simultaneously two parallel streams of successively fed bodies; and

FIG. 9 shows an apparatus, of the kind shown in FIG. 7, having a multi-level magnetic core, with a pole piece at each level.

Referring now in particular to the appended drawings, the herein disclosed method of orienting electrically conductive bodies resides in the following:

A body 1 (FIG. 1) is introduced into the space between the pole pieces, where a non-uniform magnetic field created by an alternating electric current acts thereupon, whereby the body 1 is oriented in a desired direction. In the herein dislosed example, the nonuniform electric field is created by an electromagnet having a winding 2 connected to an alternating-current supply, and a magnetic core 3 with a pair of

pole pieces

4 and 5, defining therebetween an orientation zone for the body 1. It is essential that this non-uniform magnetic field created by the alternating current should have its inductance decreasing toward the central portion of the orientation zone, which can be attained by shaping the pole pieces correspondingly, and also by appropriately positioning them relative to each other. In the apparatus illustrated in FIG. 1 this feature is attained by the

pole pieces

4 and 5 being provided each with a V-shaped cutaway portion, or cut facing the orientation zone. Such configuration of the pole pieces is responsible for the creation of a distinct retaining plane (i.e., a plane where a body is retained in an oriented position thereof), which plane, as can be seen in FIG. 2, is disposed in the central portion of the space between the pole pieces, intermediate the spaced apices of the V-shaped cuts. The inductance in this portion of the orientation zone is lower than in any other portion thereof. The herein disclosed method provides for adjusting the torque acting upon the body being oriented, by means of controlling correspondingly in any known way the frequency of the alternating current creating the magnetic field. It is possible, for example, to select a frequency so that the inductive reactance and the resistance of the body equal each other, in which case the torque acting upon the body acquires a maximal value.

The V-shaped cuts in the

pole pieces

4 and 5 can be made slanting relative to a vertical plane, as is shown in FIG. 3, in which case an upwardly flaring orientation zone is defined, whereby a body is finally retained in an oriented position at a given point. The body 6 shown by way of example in FIG. 3 is a yoke, which in the orientation zone of the kind herein illustrated would be oriented from any initial position into the finally oriented position shown, and this oriented position would be retained.

The angular value of the V-shaped cut and the degree of the slanting thereof relative to a vertical plane are selected in order to obtain a distinct retaining plane, in accordance with the actual spacing of the pole pieces.

The pole pieces may have two or even more V- shaped cuts each, as is shown in FIG. 4. In this manner it becomes possible to retain a body in an oriented position, depending on several characteristic features thereof simultaneously, e.g., by several features. Shown by way of example in FIG. 4 is a cylinder-shaped body having a dielectric housing 7 receiving thereinside an electrically conductive non-magnetic member including a thin rod 8 carrying two discs 9 and 10. Bodies of this kind can be oriented by the herein disclosed method and can be retained in an oriented position, depending on the position of their internal members. To this end, the distance between the apices of the two V-shaped cuts of each of the two pole pieces is made equal to the spacing between the discs 9 and 10 of the internal member of the body. Moreover, an orientation zone of the last mentioned shape can be used for orienting and retaining more than two streams of successive bodies simultaneously, provided the dimensions of the bodies correspond to the spacing between the respective pairs of V-shaped cuts facing each other, and that the bodies are oriented depending on a single characteristic feature thereof.

The herein disclosed method of orienting electrically conductive bodies can be performed by another, basically similar apparatus, wherein a non-uniform magnetic field acting upon the bodies being oriented is created by two electromagnets including their respective C-shaped magnetic cores l1 and 11 (FIG. 5) and windings l3 and 14 adapted to be supplied with an alternating electric current. The two electromagnets are so positioned that their similar pole-pieces are brought adjacent to each other and create a common magnetic field in the orientation zone. In the example illustrated in FIG. 5 the body being oriented is an asymmetrical stem 15 heaving a threaded end, whereby the two end portions of the stem 15 feature different electrical conductivity, and, therefore, are oriented in the magnetic field with the desired one of the two ends leading.

A structure including two electromagnets is particularly suitable for establishing a desired degree of the non-uniformity of the magnetic field in the orientation zone, which is attained by placing the lower pair of the pole pieces of the two electromagnets at a distance from each other, which is slightly greater than the respective dimension of the body to be oriented, while the other, upper pair of the electrodes is spaced from each other by a distance which is experimentally found to be the most suitable for accurate orientation. Owing to interaction of such fanshaped non-uniform magnetic field with the body being oriented, there are applied to the opposite end portions of the body the two unequal resultant components of the electrodynamic forces, F, and F respectively, which tend to oust the body from the orientation zone, whereby the inequality of these components produce a torque which turns the body into a position indicated by dotted lines in FIG. 5. By turning the two electromagnets relative to each other in a given plane and spacing them suitably in the same plane, it is easy to form a non-uniform magnetic field in this very plane of the orientation zone, whereas for forming an orientation zone featuring a three-dimensionally non-uniform magnetic field, it is advisable to employ more than two C-shaped electromagnets.

Illustrated in FIG. 6 is yet another apparatus, embodying the invention, which comprises four electromagnets with their respective magnetic cores l6, 17, 18, 19 and

windings

20, 21, 22, 23 which latter are either connected to a single source of single-phase alternating current, or else are connected to their respective individual sources, and thus create the respective magnetic fields characterized by different frequencies. The respective

adjustable clamps

24, 25, 26, 27 carried by the upright supports 28, 29, 30, 31 hold the four electromagnets above the base 32, so that the positions of the electromagnets above the base 32, so that the positions of the electromagnets can be selectively adjusted relative to one another. With the electromagnets thus arranged, successive bodies in the shape of, for example, square cups may be not only oriented for their butt ends to acquire a desired position, but they may be simultaneously rotated into a desired position of their side walls.

A method of orienting successive bodies, embodying the present invention, can also be performed by an apparatus illustrated in FIG. 7. As can be seen from FIG. 7, the electromagnet in the last mentioned apparatus comprises a core assembly including a plurality of individual C-shaped core members 35 associated with a single pair of

pole pieces

33 and 34. The pole piece 33 is positioned above the pole piece 35, and each of the plurality of cores 35 has wound thereabout a respective winding 36 having a limited number of coils. The upper pole piece 33 has a vertical passage therethrough for a body 37 to be introduced into the orientation zone, whereas the lower pole piece 34 has its own vertical passage, through which the body can leave the orientation zone after the orientation operation, the cross-sectional shape of the passage in the lower pole piece corresponding to the contour of the body in a plan view, in a desired oriented position of this body. The

pole pieces

33 and 34 are shaped as truncated pyramids, the lower bases of the two pyramids facing each other, whereby the magnetic flux is concentrated within the peripheral outline of the body 37 in any initial position thereof. With the magnetic core thus arranged, there is a funnel-shaped non-uniform mangetic field created in the orientation zone, which field provides for orienting successive bodies even in the course of their short-distance descent through the orientation zone. By the cores 35 being arranged about the whole periphery of the

pole pieces

33 and 34, it becomes possible to attain a magnetic field which is more evenly distributed in the orientation zone, the inductance of the field decreasing toward the central portion of the zone.

The magnetic core structure of the kind shown in FIG. 7 can be readily built up from a desired number of easily attachable core members 35. By having in stock a comparatively small set of such core members, it becomes possible to build up various apparatus of a similar kind with extreme ease and flexibility.

An apparatus of the last-mentioned kind can be used also for orienting simultaneously several streams of succesively fed asymmetrical bodies. For example, for orienting simultaneously two streams of

bodies

38 and 39, respectively (FIG. 8), the apparatus features two orientation zones, each of them being similar to the orientation zone illustrated in FIG. 7.

Moreover, an apparatus of the last-mentioned kind may be a multi-level one, which arrangement shows utmost efficiency, when a body cannot be oriented into a final desired position within a single space between a pair of pole pieces.

Illustrated in FIG. 9 is an apparatus with a two-level magnetic core structure, which apparatus is meant for orienting, for example, cross-shaped pieces 40. The first stage, or level of this apparatus reliably orients the body 40 by one of the planes thereof relative to the direction of its descent through the apparatus, whereas in the second stage, or level of the apparatus, i.e., in the orientation zone defined between the pole pieces 33' and 34, the body is rotated into a desired spatial position of its cross-shaped cross-section about the axis of its descent.

All of the above described kinds of apparatus can be easily associated with known feeding arrangements and can be trusted for high efficiency and speed of their operation.

What is claimed is:

1. A method of orienting and fixing nonmagnetic electrically conductive bodies under the action of a non-uniform magnetic field induced by an alternating electric current, said method comprising distributing, in a zone of simultaneous orientation and fixation, the inductance of the magnetic field in such a way that bodies are acted upon by a field with at least one nonuniform part, forming a central plane section in said part of the field, the inductance of which field tapers in said section towards a center of fixation corresponding to a minimum value of the inductance of the field, and forming the cross-section of said section relative to the field direction depending upon the form of the crosssection of the body in its position of fixation.

Claims

1. A method of orienting and fixing nonmagnetic electrically conductive bodies under the action of a non-uniform magnetic field induced by an alternating electric current, said method comprising distributing, in a zone of simultaneous orientation and fixation, the inductance of the magnetic field in such a way that bodies are acted upon by a field with at least one nonuniform part, forming a central plane section in said part of the field, the inductance of which field tapers in said section towards a center of fixation corresponding to a miNimum value of the inductance of the field, and forming the cross-section of said section relative to the field direction depending upon the form of the cross-section of the body in its position of fixation.