US559988A - Theodore berdell - Google Patents

Description

T. BERDELL.

(No Model.)

TELEPHONE.

No. 559,988. Patented May 12, 1896.

AN DREW B GBMAM. PHDTO-Lm-ICL WASHIN Gran. D c.

- UNITED STATES PATENT OFFICE.

THEODORE BERDELL, OF NEIV YORK, N. Y.

TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 559,988, dated May 12, 1896.

Application filed March 8, 1895. Serial No. 540,982. (No model.)

To aZZ whom, it may concern:

Be it known that I, THEODORE BERDELL, a citizen of the United States, residing in the city, county, and State of New York, have invented a new and useful Improvement in Telephones, of which the following is a specification.

My invention relates to telephones, particularly to such as are employed for transmitting articulate speech, and has for its object the provision of a telephone simple in construct-ion and very sensitive to sound.

My invention consists, essentially, in locating the diaphragm in a magnetic field in a position of stable magnetic equilibrium or position of magnetic equipoise as contradistinguished from an unstable position or position of magnetic bias. hen mounted in accordance with my invention, the movement or vibrations of the diaphragm in either direction away from normal position are in such direction with reference to the lines of magnetic force that it will be restored by the magnetic forces to the normal position.

My invention further consists in mounting a diaphragm which is unsecured or free to vibrate at its edges in a magnetic field in a position of stable magnetic equilibrium. \Vhen such a diaphragm is so mounted in a magnetic field and properly guided, it is practically fioated in the magnetic field.

I11 carrying out my invention the diaphragm, which is of magnetic material, as well understood in the art, may be placed in the magnetic field or lines of force joining two poles either of the same or separate magnets, its plane being practically coincident with or parallel to said lines, or the field in which it is placed may be produced by the single pole of a magnet. In either case the direction of vibration of the diaphragm would practically be transverse to the lines of force or in such direction as to tend to carry the diaphragm from a stronger to a weaker field, whereby it would be restored or drawn back to the central or normal position, which is the position of magnetic equipoise. I do not, however, limit myself to the number or special disposition of the magnetic poles or form or special direction of lines of force with reference to the diaphragm, as any mounting of the diaphragm in a position of magnetic equipoise or equilibrium in a magnetic field would be within my invention.

My invention also consists in certain other novel and useful combinations or arrangements of parts and peculiarities of construction and operation, all of which will be hereinafter first fully described, and then pointed out in the claims.

In the accompanying drawings, forming a part hereof, Figure 1 is a longitudinal vertical sectional view of a telephone embodying my invention, taken at line a a of Fig. 2. Fig. 2 is a vertical cross-sectional view at line x x of Fig. l, and Fig. 3 is a like View at line y 1 of the same figure. Fig. 4 shows the, diaphragm as located between the poles of two separate magnets, and Fig. 5 as opposite the pole of a single magnet.

Similar numerals of reference wherever they occur indicate corresponding parts in all the figures.

I will first describe my invention as carried out with a horseshoe-magnet, which, for illustration only, is shown and described as a permanent magnet.

1 is such a magnet. Between the two poles of the magnet is a box or case 2, of any approved insulating material, having an opening 3 at its front for the admission of sound.

is a diaphragm of soft iron, preferably free at its edges and guided in said case in anysuitable way. The diaphragm, as shown, is located in the magnetic field between the two poles of the magnet, and its plane is practically coincident with the direction of the lines of force joining said poles. The proper position may be practically determined by allowing the diaphragm to move in the space between the poles in a direction at right angles to the line joining said poles until it finds its position of rest or equilibrium, which, as is well known, would be just back of the ends of the poles and in the strongest portion of the field between them. If moved from this position in either direction in a line transverse to a line joining the poles, the magnetic forces would restore it to the normal position. I have found that a diaphragm so mounted is very sensitive to sound-waves, particularly to such as are produced by articulate speech. A diaphragm so mounted and arranged in a magnetic field is practically floated in a magnetic field, being kept out of contact with the 'magnet and being so floated without any mechanical clamping or holding devices at its edge is particularly free to respond to sound Vibrations.

IVhen the diaphragm operates upon electrodes, the latter are preferablymounted and supported as follows: Placed across the case 2 are pencils or cylinders 4, preferably of carbon, forming one of the electrodes of the telephone. These pencils are yieldingly supported at their ends by being held in (himbles of rubber or equivalent yielding material 5. The pencils at are electrically connected at 6, and are alsoelectrically connected to a binding-post '7, fixed in the case The binding post 8 is connected with the diaphragm or the electrode thereon. Attached to the rear of the diaphragm is a carbon electrode 11, which bears against the pencils 4. By the peculiar arrangement of yielding supports for the ends of the electrodeseall buzzing or snapping sounds are eliminated, while ample provision is made for the requisite yibration.

The parts of my telephone may be mounted and inclosed in any convenient case when in use.

I have particularly illustrated my invention as employing a magnet of the horseshoe type; but two separate magnets may be used, or a single magnet,tl1e results being practically the same. In Fi a the diaphragm 10 is shown supported upon a non-magnetic piece 12, between the poles 1 of separate magnets, and in Fig. 5 but a single magnet placed above the diaphragm is used. In all these cases the diaphragm occupies a position of magnetic equilibrium, so far as concerns vibrations of the same in response to sound-waves.

That I claim as my invention is- 1. In a telephone, a diaphragm mounted in a magnetic field in a position of magnetic equipoise or stable equilibrium, as and for the purpose described.

In a telephone, a diaphragm free at its edges and floated in a magnetic field, as and for the purpose described.

3. In atelephone, the combination,substantially as described, with a diaphragm free at its edges, of a guiding-case therefor, and a magnet or magnets in the field of which the diaphragm floats, as and for the purpose described.

4. In a telephone instrument, the combination, with a horseshoe-magnet, of a diaphragm floated in a position of magnetic equipoise in the field between the poles of said magnet, and an electrode or electrodes upon which the diaphragm operates, substantially as and for the purpose set forth.

5. In a telephone instrument, the combina tion with an insulating-support, of an electrode yieldingly mounted therein, a magnet, and a diaphragm loosely resting upon said electrode and mounted in a position of magnetic equilibrium between the poles of said magnet.

6. In a telephone instrument, a suitable support, a magnet, and an electrode formed of cylinders of carbon mounted at their ends in yielding rings within the support, in combination with a diaphragm resting upon said cylinders and loosely held in place with its plane parallel to the lines of force joining the poles of said magnet, substantially as shown and described.

7. In a telephone instrument, a support, a magnet and a pair of carbon cylinders yieldingly mounted within the support and forming an electrode, in combination with a diaphragm loosely held in place in or about the position of magnetic equipoise in the field of force of said magnet and bearing an electrode, as and for the purpose described.

THEODORE BERDELL. V itnesses:

A. M. PIERCE, E. D. \VRIGHT.

Images