US2567290A

US2567290A - Magneto

Info

Publication number: US2567290A
Application number: US77800A
Authority: US
Inventors: Stanley D Livingston
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-02-23
Filing date: 1949-02-23
Publication date: 1951-09-11
Anticipated expiration: 1968-09-11

Description

p 1951 s. D. LIVINGSTON 2,567,290

MAGNETO Filed Feb. 25, 1949 Ti q-E.

' INVENTOR. 0/ 3, 36 BY 4mm 5. W

A TTORA/EY Patented Sept. 11, 1951 UNITED STATES PATENT OFFICE 2,567,290 MAGNET?) Stanley D. Livingston, Freeport, N. Y. Athenian retina-3 23, 1949, seen no. 75.800 8 Claims. (01. 171 -209) This invention relates to the generation of electricity, especially to the generation of electricity by means of an electro-magnetic,machine and particularly one in which an armature of magnetic material is moved in the path of the magnetic flux of a permanent. magnet.

A principal object of this'invehtio'n is to produce an electric generator of the magneto type operable intermittently by a manual operation which is suitable for being built into an ordinary portable camera for the purpose of furnishing the necessary electric current to ignite the ordi nary and well known flash, light bulbs.

A further object of theinventien is to produce a device of the characte'rstated which is so constructed that after each manual operation it returns automaticallyto initial position as soon as the force used in operating it iswithd'rawn.

Other objects and advantageswillappear as the description of the particular physical embodiment selected to. illustrate the invention progresses and the novel features willbe particularly pointed out in the appended claims. I r

.In describing the invention in detail and the particular physical, embodiment selected to illustrate the invention, reference will be had to the accompanying drawings and the severalviews thereon, in which like characters of reference designate like parts throughout the several views,

andin which: v, p v

Fig. 1 isa front elevationalview of a device embodying my invention; Fig.2 is a side. elevational view of the device as shown by Fig. l, viewed from the right hand side thereof; Fig. 3 illustrates magnetic flux lines under one condition of the device as shown by Fig. 1; and Fig. 4 shows another condition of magnetic flux lines when the device of Fig. l is in a different condition from that shown in Fig.3; Fig. 5 is an elevational view of a modified form of device embodying my invention.

The core of my magnetois in two parts designated l and 2. l extends from the point ,3 to the point 4. 2 extends from the point 5 to thepoint B. Each of the cores l and 2 is formed, of course, in accordance with best engineering practice. They are preferably formed of stacked thin magnetic material. I prefer the well known'silicon steel as the material. v

The face 1 is formed on core 2 and a face 8 is formed on core I. Betw'een'th'ese faces is positioned a permanent ni'agriett, the end faces of which bear against the faces 1 a 'r 1d'8. v v .In order to keep parts I, Z Iandlinproperposition and relation, rempmyniestrap In. This strapis made of a non-magnetic material and is preferably attached by drive screws such as l I, I2, I3 and I4 driven through orifices in the strap l0 directly into the material of the laminations of the cores I and 2, after these cores have been brought together so as to tightly and strongly maintain the permanent magnet 9 in place. The strap [0 is formed with a through out outportion [5. If, after the strap has been put inplace, the permanent magnet 9 is not sufficiently tightly held, then the sides of the cut-out portion 15 and the sides 16 and I! of the cut-out portion f5 are caused to move away one from the other by anysuitable tool so as to draw the cores I and 2 more tightly together against the permanent magnet9. Y 7 p i I I I The dimensions of the parts are such thatwhen the cores are in place with the permanent magnet 9 therebetween and the strap 10 holding them together, a relatively small air gap l8 isprcsent between the ends of the cores l and 2 aswell as a greater air gap at the point I 9.

Wire wound coils

20 and 2| connected in series are positioned one upon the core 2 and the other upon the core I, each being between two air gaps. Spanning the air gap I9 is an armature 22. This armature is formed of a magnetic material and preferably, is laminated in accordance with usual and best engineering practice. In the position as shown in Fig. 3 the armature 22 connects core I with core 2 so that there is a path for magnetic flux through the permanent magnet through the core I and armature 22 as shown by full line 23 in Fig. 3. This path is one of'small reluctance as compared with the path for the magnetic flux when the armature has been positioned as shown in Fig. 4 as there then will exist the air gap between one end of the armature and the core 2.

The member H3, or strap, serves not only to hold the parts together but it also has an extension 24 projecting beyond the main cores 1 and 2. The strap 10 is in duplicate, that is, as best shown in Fig. 2, there is a strap ID on one side of the cores and also an identical strap on the other sides of the cores. Between these two straps and attached thereto is a pin 25 which extends out beyond the straps on each side as best'shown in'Fig. 2. An actuating lever 26 is pivoted upon the pin 25 so that it may rotate on the pin 25. This actuating lever may extend in any direction,'either downwardly as shown in Fig. l or to the right or left or upwardly. This actuating leveris in the form of a U, that is, one

side of'theu "extends along one side or the cores v r 3 and the other side of the U along the other side of the cores, as best shown in Fig. 2. There are projecting legs, as 21, one projecting from each of the legs of the U. At the outer end of these projecting legs 21 there is a rod 28 connected therebetween.

One end of a flat spring 29 is wound about the rod 28 so as to be held from displacement. This spring extends to the right, as viewed in Fig. 1, and its free end passes above and rests on a rod 30 connecting the straps on each side of the cores.

The left hand end of extension of the leg 21 moves upwardly as the manually actuating lever pivots on the pin 25. As this leg 2'! moves up, it initially tensions the spring 29 against rod 3| but no movement takes place of armature 22 until .the arm 21 actually contacts the end of rod or protuberance 3| whereupon the armature is moved upwardly a slight amount necessary to separate one end thereof from the core 2 and then the spring 29 has sufficient tension therein to snap the armature upwardly to a position as shown in Fig. 4. The limit of upward movement of the armature 22 is governed by the pin 25 because that pin rides in a slot 32 of the armature.

As long as manually actuating lever 2'6 is held sufiiciently to the left, the armature 22 cannot return to its initial position as shown in Fig. 3, but upon releasing arm 26, it moves toward the position as shown in Fig. l and the armature 22 moves downwardly toward the position as shown in Fig. 3, but before it reaches its final position, the rod 3| contacts spring 29 and the position to which the armature will drop is such that the magnetic attractive force toward the right hand end of the armature exerted by the end of core 2 will be sufficient to snap the armature down into place as shown in Fig. 3 and at the same time slightly tension the spring 29.

With the armature in the position as shown in Fig. 3, a major portion of the magnetic flux is through the path designated by the full line 23 and a minor portion through the path indicated by the dotted line designated 33. When the armature is moved to the position as shown in Fig. 4 a minor portion of the flux is through the path indicated by the dotted line 23 of Fig. 4 and a major portion through the path indicated by dotted line 33 of Fig. 4. The result is, that there is a reduction or collapse of flux through coil 2| and an increase of flux through coil 29 so that in both coils a magneto-motive force is generated which will cause a flow of current through the

terminals

34 and 35.

In the preferred form of my device I prefer to make the two paths for

magnetic flux

23 and 33,

such that when the armature 22 is in the positionas shown in Fig. 3, the main path, 23, has about ten times the flux therethrough as through the path 33. When the device is in the condition as shown in Fig. 4, the path 23 will contain about one-tenth the magnetic flux of the path 33.

In my preferred form I use, as a permanent magnet 9, a body of magnetic material composed of aluminum and nickel and cobalt and known by the trade name of Alnico.

Fig. 5 is a View of a modified form of my invention. In this form of my invention an air gap such as [8 of Fig. 3 is formed as shown at 36 of Fig. 5 is made at an angle other than a right angle to the core 31 and core 38. This provides an air gap of greater area.

The permanent magnet 39 of Fig. 5 is not placed on the skew as in the other forms.

The armature d of the form in Fig. is generally formed in that it has a somewhat semi:

circular contour M which contacts with

curved portions

42 and 43 of the

cores

38 and 31. The area of contact of the armature 40, in the form shown by Fig. 5, is, therefore, greater than the area of contact in the other form shown.

The spring 44, in Fig. 5, is looped around the pin 30 rather than around the pin 28 as in the other figures. In the form shown in Fig. 5 the rod 25 of the other figures would not be made continuousbut only have its ends used so as not to interfere withthe spring 44.

The device hereinbefore described is employed for furnishing the necessary current for firing the well known flash bulbs used in photography for illuminating subjects to be photographed. The above device can be made in a size for application to the majority of small cameras in a size such that it is not more than 2 inches by 2% inches by of an inch so that it will add very little to the bulk ofa camera, but a camera equipped therewith is independent of batteries for firing flash bulbs.

Although I have particularly described one par-' ticular physical embodiment of my invention and explained the construction and principle thereof,

What I claim as new and desire to secure by Letters Patent is: I

1. A magneto, comprising, in combination: core formed with an air gap therein; a permanent magnet connected to the core causing a' magnetic flux therethrough; an armature spanning the air gap; a manually operable pivoted lever; a protuberance on the armature positioned to lie in the path of the-pivoted lever when operated; a fiat spring attached atone end to the lever; a member fixed with respect to the core supporting the other end of the lever and said protuberance bearing against the mid-portion of the spring whereby a movementof the lever causes an initial separation of the armature from one end of the core and the spring causes a wide snap separation of the armature and said one of greater reluctance than the other, coils, one positioned to be threaded by the magnetic flux in one pa th, and another positioned to be threaded by the magneticflux in the other path, an armature of magnetic material bridging the larger air gap and means to disturb the positioning of the armature to increase the reluctance of the mag-I netic circuit through the path in which the air gap of greater reluctance is positioned, said coils connected for cumulative effect whereby the movement of the armature causes a decrease in magnetic flux in one path and an increase in magnetic flux in the other path.

3. A magneto, including, in combination, a

permanent magnet, two cores of magnetic mate rial disposed about the permanent magnet, said cores positioned to provide two separate magnetic flux paths through the permanent magnet, each path including an air gap, one gap being of greater reluctance than the other, coils, one positioned to bethreaded b the magnetic flux in one path, and another positioned to be threaded by the magnetic flux in the other path, an armature of magnetic material bridging the larger air gap, a pivot fixedly positioned relative to the permanent magnet and cores, a crank having an arm for receiving force and an operating arm oscillatable about the said pivot, a protuberance on the armature positioned in the path of movement of the operating arm, a member fixedly positioned with relation to the said pivot, a spring engaging member on the operating arm, a flat spring having one end engaging the mem= ber fixedly positioned with relation to the said pivot, the other end with the spring engaging member on the operating arm and an intermediate portion engaging the protuberance on the armature.

4. A magneto, including, in combination, a permanent magnet, two cores of magnetic mate rial disposed about the permanent magnet, said cores positioned to provide two separate magnetic fiux paths through the permanent magnet, each path including an air gap, one gap being of greater reluctance than the other, coils, one positioned to be threaded by the magnetic flux in one path, and another positioned to be threaded by the magnetic flux in the other path, an armature of magnetic material bridging the larger air gap, a pivot fixedly positioned relative to the permanent magnet and cores, a crank having an arm for receiving force and an operating arm oscillatable about the said pivot, a protuberance on the armature positioned in the path of movement of the operating arm, a member fixedly positioned with relation to the said pivot, a spring engaging member on the operating arm, a fiat spring having one end engaging the member fixedly positioned with relation to the said pivot, the other end with the spring engaging member on the operating arm and an intermediate portion engaging the protuberance on the armature, said protuberance on the armature being so positioned with relation to the operating arm when the armature bridges the air gap and is closely held to the cores that the operating arm may be oscillated to somewhat tension the fiat spring before the operating arm comes in contact with the protuberance on the armature.

5. A magneto, including, in combination, a permanent magnet, two cores of magnetic material disposed about the permanent magnet, said cores positioned to provide two separate magnetic flux paths through the permanent magnet, each path including an air gap, one gap being of greater reluctance than the other, coils, one positioned to be threaded by the magnetic flux in one path, and another positioned to be threaded by the magnetic flux in the other path, an armature of magnetic material bridging the larger air gap, a pivot fixedly positioned relative to the permanent magnet and cores, a crank having an arm for receiving force and an operating arm oscillatable about the said pivot, a protuberance on the armature positioned in the path of movement of the operating arm, a member fixedly positioned with relation to the said pivot, a spring engaging member on the operating arm, a flat spring having one end engaging the member fixedly positioned with relation to the said pivot, the other end with the spring engaging member on the operating arm and an intermediate portion engaging the protuberance on the armature, said protuberance on the armature being so positioned with relation to the operating arm when the armature bridges the air gap and is closely held to the cores that the operating arm may be oscillated to somewhat tension the flat spring before the operating arm comes in contact with the protuberance on the armature, and means to limit the movement of the armature from the cores.

6. A magneto, including, in combination, a magnet presenting two spaced poles, an armature of magnetic material extending from pole to pole, a pivot fixedly positioned relative to the magnet, a crank having an arm for receiving force and an operating arm oscillatable about said pivot, a protuberance on the armature positioned in the path of movement of the operating arm, a member fixedly positioned with relation to the said pivot, a spring engaging member on the operating arm, a flat spring having one end engaging the member fixedly positioned with relation to the said pivot, the other end with the spring engaging the member on the operating arm and an intermediate portion engaging the protuberance on the armature.

7. A magneto, including, in combination, a magnet presenting two spaced poles, an armature of magnetic material extending from pole to pole, a pivot fixedly positioned relative to the magnet, a crank having an arm for receiving force and an operating arm oscillatable about said pivot, a protuberance on the armature positioned in the path of movement of the operating arm, a member fixedly positioned with relation to the said pivot, a spring engaging member on the operating arm, a fiat spring having one end engaging the member fixedly positioned with relation to the said pivot, the other end with the spring engaging member on the operating arm and an intermediate portion engaging the protuberance on the armature and means to limit the movement of the armature from the cores.

8. A magneto, including, in combination, a core, windings on the core, said core provided with an air gap, a permanent magnet bridging the air gap, an armature bridging the air gap, a pivoted two arm crank, cooperating members on one crank arm and the armature whereby the armature is raised at one end from the core by the manual operation of the other arm while the other end remains in contact with the core acting as a pivot point.

STANLEY D. LIVINGSTON.

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

UNITED STATES PATENTS Number Name Date 1,517,997 Louis Dec. 2, 1924 1,700,677 Hendrickson Jan. 29, 1929 1,708,095 Hubbell Apr. 8, 1929