US824046A - Electromagnet. - Google Patents

Description

No. 824,046. PATENTED JUNE 19, 1906.

I O. F. A. STURTS.

BLEGTROMA'GNET.

APPLICATION HLBD APR.28,1905.

FIG

15 W/ 7/1 55555 //v MFA 70R" CHARLES F. A. STURTS, OF SAN FRANCISCO, CALIFORNIA.

ELECTROMAGNET.

Specification of Letters Patent.

Patented June 19, 1906.

Application filed April 28,1905. Serial No. 257,878.

To all whom, it may concern:

Be it known that I, CHARLEs F. A. STURTs, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvements in Electromagnets, of which the following is a specification.

My invention relates to electromagnets capable of being used for all the purposes in general for which such magnets are adapted, but having especial reference to employment in situations where it is desirable that their operation shall be noiseless.

In constructing electrical winding apparatus for timepieces, such as that shown in my application for patent, Serial No. 21 1,056, filed June 3, 1904, I have found that in using ordinary magnets for operating the winding mechanism the direct pull of the armature into contact with the poles causes a sharp click, and as this noise is repeated many times in the course of a day it is to some eX- tent objectionable. The magnet which is the subject of the present application obviates this objection, its operation being noiseless, and this advantage is obtained without in any way affecting or detracting from its efiiciency.

I have shown my improved magnet in the accompanying drawings in connection with an arbor and ratchet-wheel as illustrative of one of its practical uses.

Figure 1 is a plan view of the magnet and armature in connection with a ratchet-wheel and arbor. Fig. 2 is a sectional elevation of the magnet and armature. Fig. 3 is a sectional elevation of the same at right angles, one spool having been removed.

The operative parts of the invention are shown as mounted upon a plate 1, which may be a support for a clock-movement or any other support. A shaft or arbor 2, journaled in the bridge 3, attached to the plate 1, carries a ratchet 4. For these devices any others can be substituted, as they are shown here only to illustrate one derivation of motion from the armature of the magnet. The ratchet-wheel and arbor may be supposed to form part of an electrical winding system for timepieces, the ratchet being moved intermittently, and so operating the arbor and any parts connected to it.

The electromagnet is composed, as usual, of two spools 5 6, having proper windings and provided with interior cores 7 8 the ends of which are preferably substantially even with the ends of the spools and form the poles. The cores are secured by countersunk screws 9 11 to the base 12, so that the cores are in magnetic connection. The basepiece 12 has a hole between the spools, in which is set the hollow standard or bearing 13, the end of which is reduced to fit said hole. The shoulder thus formed rests upon the base-piece.

Mounted loosely in the bearing 13 is a rod 14, one end of which projects beyond such bearing. The bore of the bearing is slightly reduced near its end adjacent to the basepiece, so as to form a stop for the rod 14, and the reduced part is threaded. A hole 15 in the plate 1 admits a screw 16, which enters and engages with the threaded part and can be caused to bear upon the end of rod 14, so that the osition of such rod 14 can be accurately a justed.

The projecting end of rod 14 carries the armature 17, which is a bar of soft iron of such length as to extend in both directions to and across the magnet-poles; but the adjustment is such that the armature is never in contact with the oles. The magnet is thus adapted to swing from the position shown by'full lines in Fig. 1 to the position shown by dotted lines in the same figure. The normal position when no current is in the coils is inclined to a line drawn between the centers of the two poles, as shown. When the magnet is energized, the armature swings by magnetic attraction to a position in which it is directly opposite and adjacent to said poles, but not in contact with either of them.

A coil-spring 18 is connected to the armature-rod 14 and to the standard 13, the tension of which is suflicient to hold the armature in its normal position and to return it to that position when the circuit is open. The spring is located between the armature and the coils, so as to be protected and out of the way, and the magnetic attraction is sufficient to overcome the spring when the circuit is closed.

As illustrating the transmission of mechanical energy by the armature I have shown an arm 19, secured to the rod 14 and projecting outwardly. This arm has a stud 21, which operates the ratchet one tooth whenever the armature is attracted. This arm is preferably made of thin elastic metal, so that it can be moved sidewise by the ratchet and will then spring in back of the next tooth, and

and holds such rod in place.

The operation of the device will be readily understood. hen the magnet-coils are energized, the attraction of the poles draws the ends of the armature in opposite directions to the position opposite and adjacent to them. As the armature is never in contact with either pole, its operation is noiseless, and the click caused by sudden sharp contact with the metal poles is done away with. At the same time it is perfectly effective as a means for transmitting mechanical energy.

In order to prevent the possibility of any noise caused by the armature striking its stops, I prefer to provide such stops with surfaces or cushions of leather or other suitable material, as shown at 25.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an electromagnet, the combination withthe spools and the pole piece or base upon which they are mounted, of a hollow standard on said base, an adjustable rod j ournaled in said standard and an armature carried by said rod.

2. In an electromagnet, the combination with the spools and the pole piece or base upon which they are mounted, of a hollow standard on said base, an adjustable rod journaled in said standard and an armature carried by said rod, and means for adjusting said rod in said standard.

3. In an electromagnet the combination with the spools and the pole piece or base upon which they are mounted, of a hollow standard on said base, an adjustable rod journaled in said standard and an armature carried by said rod, and a screw entering said standard and adapted to bear upon said rod.

4. In an electromagnet, the combination with the spools and the pole piece or base upon which they are mounted, of a hollow standard on said base, a rod journaled, in said standard, an armature carried by said rod, and a coiled spring connecting said standard and said rod.

5. In an electromagnet, the combination with the spools and the pole piece or base upon which they are mounted, of a hollow standard on said base, an adjustable rod journaled in said base, a coiled spring connecting the rod to the base, and an armature carried by said rod, substantially as described.

6. In an electromagnet, the combination with the magnetspools of an intermediate hollow standard or bearing, a rod j ournaled therein and projecting beyond it, an arma ture carried by said rod, and a three-branched bracket having one branch secured to said standard, the other branches of which are respectively stops for the opposite ends of the armature.

7. In an electromagnet, the combination with the spools and the pole piece or base upon which they are mounted, of a hollow standard on said base, an adjustable rod journaled in said standard, an armature carried by said rod, and an arm of thin elastic material having one end connected to said adjustable rod for transmitting power derived from the movement of the armature.

In testimony whereof I have affixed my signature, in presence of two witnesses, this 10th day of April, 1905.

CHARLES F. A. STURTS.

Witnesses:

CELESTE ANsELL, HENRIETTE BURT.

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