US178216A

US178216A - Improvement in electro-magnetic annunciators

Info

Publication number: US178216A
Authority: US
Publication date: 1876-05-30
Anticipated expiration: 1893-05-30

Description

A. s. WETMORE. ELECTRO-MAGNETICJANNUNCIATOR.

No. 178,216 Patented May 30,1876.

N.PEYERS. FNOTO-LITHOGRAPHER, WASHINGTON. D c.

UNITED STATES PATENT QFFIC'EL ALBERT s. WETMoRE, oFoLEvELANn, OHIO, ASSIGNOR OF oNE-HALEHIs RIGHT To EDWARD MILL, OF SAME PLACE.

IMPROVEMENT IN ELECTRO-MAGINETIC ANNU'NCIATORS.

Specification forming part of Letters Patent No. 178,21 6, dated May 30, 1876; application filed October 29, 1875.

To all whom it may concern:

of Ohio, have invented an Electric Annunciator, of which the following is a specification:

This invention relates to a new construction of electromagnetic annunciators and consists in the combination, with an electro-inagnet, of a thin, magnetized steel armature, poised or balanced in an opening made in a plate covering the front ends of the magnet, said plate also serving to insulate the armature from the magnet. The armature has a rear projecting arm, which serves as a counter-balance to hold it up when disengaged, and bymeans of which it is also disengaged from the magnet, in connection with a suitable mechanical appliance for that purpose. The said armature has upon its outer face a number, which is brought into view when drawn down by the electromagnet.

To enable others to fully understand my invention, I proceed to describe the same in detail with the aid of the accompanying drawing, in which- Figure 1 is a front view. Fig. 2 is a vertical section in line m w of Fig. 1. Fig. 3 is a detached View of the armature.

A is an electro-magnet, incased in a suitable box, B. To the front of said box Ifix a metal plate, 0, next to the ends of the cores of the magnet A. The front side of said plate 0 may be coated with silver or covered with paper. This plateinsulates the armature from the magnet. D is a thin plate of magnetized steel, which serves both as the armature and the number-plate. It has anarm, '11, which reaches inward, and. serves as a counterbalance to hold the armature up when disengaged from the magnet. The said armature is poised in a triangular opening, e, made in the plate 0, it having notches in the edge of the arm at its junction with the plate, so that it cannot slip out, and it is very easily tilted by the attractive force of the magnet. F is a frame supported in springs ff, and is situated just behind the plate G, and has a knob ,outside the case. This frame is employed for disengaging the arm-ature from the magnet.

The operation of this arrangement is as follows: On closing the electric circuit the armature D is attracted, and quickly turns down by the attractive force of the electro-magnet, bringing the number into View, as seen in Fig. 1, and it, being a permanentmagnet, will remain in that position after the electrical circuit has been broken, and it also adheres with considerable tenacity, so it is not liable to' be jarred or shaken off. When it is desired, however, to release it, the frame is drawn down by the knob, which throws itinto the position seen in Fig. 2, and the arm d, over-balancing it, holds it up until the circuit is again closed. I Having described my invention, I claim-- 1. The plate 0, placed in front of the magnets A as an insulating medium, through which the armature D is actuated, substantially as specified.

2. The combination, with themagnet A and ALFRED ELWELL.