US664061A - Electric switch. - Google Patents

Description

- .No. 664,06l. I Patented 066. I8, |9 0.

. c. w. SCOTT.

ELECTRIC SWITCH.

(Application filed Aug. 16, 1900.)

2 Sheets-Sheet I.

(No Model.) v

THE uoams versus co vucTau-mou WASHINGTON 0.1:,

' No. 664,06l. Patented Dec. 18, I900.

C. W. SCOTT.

ELECTRIC SWITCH.

plication filed Aug. 16 1993 (No Moda l.) 2 Sheets-Sheet 2.

1a fill 5% zw a' jifl/ew/or CWM 74552 0517 N'ITED STATES PATENT Fries.

CHARLES WV. SCOTT, OF LYNOHBURG, VIRGINIA.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 664,061, dated December 18, 1900.

Application filed August 16, 1900. Serial No. 27,095. tNo model.)

To all whom it may concern..-

Be it known that I, CHARLES W. SCOTT, a citizen of the United States,residing at Lynchburg, in the county of Campbelland State of Virginia, have invented new and useful Improvements in Electric Switches, of which the following is a specification.

I My invention relates to electric switches, the same being particularly designed for use in connection with the switchboard of atelephone-exchange system.

One object of the invention is to provide means whereby a plurality of circuits leading to the drops of the switchboard may be simultaneously broken or cut out and afterward simultaneously grounded.

A further object of the invention is to provide means whereby in the event of trouble on the circuit to one or more of the drops said circuit or circuits may be cut out and grounded without interfering with the remaining circuits.

Other objects and advantages of the invention will hereinafter appear, and the novel features thereof will be set forth in the claims.

In the drawings forminga part of this specification, Figure 1 is a sectional side elevation of my improved switch. Fig. 2 is a front elevation of the same, and Figs. 3 and 4 are cross' sectional views showing the movable portion of the switch in two of its positions.

Like reference-numerals indicate like parts in the different views.

My improved switch is mounted in a frame or casing, and consists of a back piece 1, of wood, hard rubber, or other insulating material, vertically disposed and secured at its upper and lower ends to the frame or casing in which it is mounted. In the front surface of the back piece 1 are formed two preferably V- shaped channels 2 and 3, extending throughout the length thereof. The channel 3 has communicating with it at its apexa groove 4,in which is located a grounded metallic conductor 5. Located within the channel 3 and arranged at regular intervals apart is a plurality of spring contact-strips 6 6, each of said strips being bent at an intermediate point, as shown at 7, and coiled around and soldered to the grounded conductor 5, so as to make close contact therewith, One end of each of the contact-strips '6is free, while the other end thereof is bent outwardly upon the face of the back piece 1 and secured thereto. The means of attachment of this end of each of the strips 6 to the back piece 1 may be by a screw 8 and washer 9, as shown, 'or it may be by any other suitable means which Will provide for the electrical connection of a wire with the strip 6 at the point named. In the channel 2 is secured a plurality of spring contact-strips 10, arranged at regular-intervals apart, but directly opposite the strips 6 in the channel 3. One end of each of the strips 10 is free, as shown, while the other end is bent around the front and side of the back piece 1 and is connected, through the wire 11, with one of the drops of the switchboard. In the event that a metallic-return-circuit system is employed two of the strips 10 may be utilized in each circuit to each annunciator of the switchboard, whereas if a common return is employed one only of the strips 10 will be required in each circuit to the annunciator-drops.

In connection with the foregoing parts I employ a movable bar 12, extending from the top to the bottom of the back piece 1 and adapted to be supported in its movements upon the sill 1 3 of the frame or casing in which the device is mounted. This bar 12 is formed with a tapering edge 14:, corresponding to the size and shape of and adapted to fit within either'the channel 2 or the channel 3. Said bar is also provided with knobs or handles 15, by means of which it may be readily manipulated. Secured to the bar 12 and extending around the tapering edge 14 thereof is a plurality of contact-strips 16, located at regular intervals apart and designed to engage the contact- strips 6 or 10 in the channels 3 and 2. One end of each of the strips 16 is secured to the side of the bar 12, while the other'end after passing around the tapering portion 14 of said bar is secured to the front edge thereof or that edge opposite the tapering portion 14. The means of connection between this end of each of the strips 16 and the front edge of the bar 12 may be by means of a screw 17 and Washer 18 or by any other means which will provide for the connection of a circuit-wire with said strip 16. Each of said strips 16 has in effect connected with it by means of the screw 17 and washer 18 an insulated coiled wire 19, connected with the line. The Wires 19 are insulated to prevent any contact except that desired and to prevent injury to the same through the manipulation of the bar 12. They are also coiled to make them pliable or yielding and to permit of the free movement of the bar 12. The normal position of the bar 12 is in the channel 2 in the back piece 1. When in this position, the contact-strips 16 engage the contact-strips 10, and the circuit is closed from the line through the annunciator-drops of the switchboard. In the event of an electrical disturbance dueto an approaching storm or a high-tension cross all of the annunciatordrops may be instantly cut out by removing the bar 12 from the channel 2 and breaking the circuits between the contact- strips 16 and 10. These circuits may then be grounded by introducing the bar 12 into the channel 3 and bringing the strips 16 and 6 into contact with each other. As the strips 6 are directly connect-ed with the grounded conductor 5, it will be obvious that all of the circuits through the wires 19 from the line will be grounded through the conductor 5.

Now it may be that a disturbance will be noted by the switchboard attendant or operator upon one or more of the drops of the switchboard from one cause or another. In such event the bar 12 may be moved from the channel 3, breaking all of the circuits, and introduced into the channel 3, grounding all the circuits. The wires 19, corresponding with the circuits of the annunciator-drops which have indicated a disturbance,may then be disconnected from the strips 16 on the bar 12 and connected directly with the corresponding strips 6 in the channel 3. These circuits will then be grounded, and no further trouble can take place in the affected annunciators. At the same time the bar 12 may be returned to its position in the channel 2, closing the circuits from the line to the switchboard and permitting the remaining portion of the system to be operated. It will thus be seen that when one drop is out of order it is not necessary that the whole system should be cut out on account of it. In Fig. 2 of the drawings I have shown one of the wires 19 connected directly with one of the contacts 6, while the circuits are closed between the remaining wires 19 and the strips 16 and 10.

From the foregoing description it will be observed that by providing the connection described between the line and the switchboard the universal disadvantage caused by the old-style screw-and-Washer connection in the cross-heads of exchanges is entirely obviated. For it a safer and more satisfactory contact is furnished.

It is generally conceded that no lightningarrester or other device for short-circuiting or diverting high-tension currents gives absolute protection from the damaging results of such currents, which, as is well known,

cause in many instances the entire destruction of valuable plants and a daily annoyance, solicitude, and expense. It is also universally admitted that neither operators nor subscribers should be permitted to use telephones during a storm. It is further true that nearly every exchange suffers more or less from the electrical disturbances caused by storms of even small moment; yet with the old-style screw-andwasher connection the idea of disconnecting each conductor is out of the question, for the reason that the notification of the approach of a storm would not give sufficient time to disconnect the con- .ductors and for the further reason that the undertaking would be tedious and would require a greater loss of time than subscribers would consent to. Furthermore, it would require fully as much time to reconnect the switchboard as to open the line. By my invention, however, an exchange of one thousand subscribers may be disconnectedin less than ten seconds and reconnected just as quicklythat is to say, one thousand circuits can be broken and grounded within ten seconds, and within the same space of time the same number of circuits can be closed and ready for business.

The most fruitfulsource of constant an noyance and expense is due to sneak currents, which do not possess sufficient electromotive force to do violent sudden damage, but by reason of the stubborn continuity of attack, the great ditliculty of locating their origin, and the time required in removing the cause they create trouble by the burning of the insulation from the wires of the drops and by permanently magnetizing the armatures of the drops, thereby preventing the vibration of the drops and completely disabling incoming signals. By my invention this trouble and expense are entirely obviated, for at the lirstintimation of a current of abnormal pressure coming in on any conductor that portion of any section of the switchboard is at once disconnected without interference with other conductors and by immediately transferring the bar 12 of the section of the system corresponding with the affected section of the switchboard to the channel 3 the conductors 19, having the high-pressure current, are secured to the proper screws 17 and washers 18, which continues them grounded until the trouble is relieved. Afterward the bar 12, with the conductors not afiected, is returned to its normal position in the channel 2. When the conductors which are left grounded are relieved from the cause of the trouble, they are replaced by connecting them to their regular posit-ions on the bar 12 without disturbing the other conductors at all. Of course as the bar 12 is transferred to the channel 3, which grounds or short-circuits to earth the conductors of that particular bar, the wires or conductors carrying high-tension currents are easily detected by a sparking coil.

In the drawings I have shown twenty-four contact-strips 16 on the bar 12 and a corresponding number of contacts in the channels 2 and 3. I do not, however, limit myself to this particular number, as a greater or less number may. be successfully employed. I find it of advantage, however, to locate on each of the bars 12, which may be used in connection with a single switchboard, fifty contactstrips, so that two of my circuitbreakers will be necessary for each section of one hundred subscribers on theswitchboard.

I have described herein but one embodiment of my invention, which is deemed'by me at this time to be the preferable one. It will be apparent, however, that many minor changes and modifications may be made therein without departing from the nature or spirit of my invention. Ido not care, therefore, to be limited to the specific construction shown and described, except asdefined in the ap pended claims. 1

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

1. In an electric switch, the combination with a back piece having a channel therein and a plurality of contacts in said channel, of a movable bar having a tapering edge adapted to fit within said channel, and contacts secured to said tapering edge and adapted to engage respectively the contacts in said channel, as and for the purpose set forth.

2. In an electric switch, the combination with a back piece having a tapering channel therein, and a plurality of contacts in said channel connected with the switchboard of a telephone-exchange system, of a movable bar having a tapering edge adapted to fit within said channel and a plurality of contacts secured to said tapering edge, connected with the line wires of a telephone system and adapted to engage respectively the contacts in said channel, as and for the purpose set forth.

3. In an electric switch, the combination with a back piece having two channels therein, of a plurality of contact-strips in one of said channels connected with the switchboard of a telephone-exchange system, a plurality of contacts in the other of said channels connected to a grounded conductor, a movable bar having a tapering edge adapted to fit within said channels, and a plurality of conductors secured to said bar, connected with the line -wires of a telephone system and adapted to engage respectively the contacts in said channels, as and for the purpose set forth.

4. In an electric switch, the combination with a back piece of insulating material having a plurality of V-shaped channels therein and having a groove communicating with one of said channels, of a plurality of contactstrips separated one from the other secured within one of said channels and connected with the switchboard of a telephone-exchange system, a grounded conductor extending through said groove, a plurality of contactstrips separated one from the other secured within the other of said channels and wound around and secured to said grounded conductor, a movable bar having a tapering edge adapted to fit within said channels, a plurality of contact-strips separated one from the other, secured to said bar and adapted to engage respectively the contactstrips in said channels, and a plurality of coiled conductors connected with the line-wires of the telephone system and to the contact-strips on said bar, as and for the purpose set forth.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

CHARLES W. SCOTT.

Witnesses:

WM. M. STOCKBRIDGE, GEO. W. REA.

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