US901331A - Electric railway-signal. - Google Patents

Description

E. A. EVERETT. ELECTRIC RAILWAY SIGNAL. APPLICATION nun mun, 100a.

Patented Oct; 20

1908. 2 SHEETS-SHEET 1.

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E. A. EVERETT. BLEOTRIG RAILWAY SIGNAL. APPLICATION rmm mm: 27, 1900.

Patented 0011.20, 1908. 2 BEEET-BEBET 2.

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EDWARD A. EVERETT, OF DETROIT, MICHIGAN.

Emo'mrc RAILWAY-SIGNAL.

Specification of Letters Patent.

Patented Oct. 20, 1908.

Application filed June 27, 1906. Serial No. 328,667.

To all whom it may concern:

Be it known that I, EDWARD A. EVERETT, a citizen of the United States, residing at Detroit, in the county of Wayne, State of Michigan, have invented certain new and useful Improvements in Electric Railway- Signals; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

This invention relates to electric railwaysignals, and consists in the construction and arrangement of parts hereinafter fully set forth and pointed out particularly in the claims.

The object of the invention is to provide simple and efficient means in connection with the relays employed in the operation of antomatic block signals for effecting an auxiliary release or circuit-breaking device, whereby upon the release of the relay or electro-magnet, the signal circuit will be automatically broken, even in the event of the fusing of the contacts at the point where the circuit is usually broken in the ordinary op eration of the device.

The above object is attained by the structure illustrated in the accompanying drawings, in which Figure 1 is a diagrammatical View of a portion of a block signal system, associated with a railway track, and illustrating the application of my invention. Fig. 2 is an enlarged view in elevation, showing the relay or electro-magnet and associated parts,including my automatic release or circuit breaker. Fig. 8 is a similar View, showing a slightly modified form of the invention. Fig. t is a sectional view through the base of a relay, as on line 4-4 of Fig. 5, showing in a complete apparatus the embodiment of the structure illustrated in Fig. 3. Fig. 5 is a horizontal section as on line 5-5 of Fig. 6. Fig. 6 1s a sectional vlew through the base of a relay, illustrating a complete embodiment of the structure shown in Fig. 2. Fig. 7 is a sectional view through the glass mercury cup, which, in conjunction with a movable contact forms the auxiliary circuit breaker. Fig. 8 is a perspective view of said cup. Fig. 9 is a View similar to Fig. 2, showing the position of parts when the circuit is opened by the auxiliary circuit breaker.

Fig. 10 is a rear elevation of the yoke in which the jointed armature is mounted.

It is common in the art of automatic block signal systems to employ carbon or graphite contacts on relays or electro-magnets for making and breaking the signal circuits; these materials are objectionable however, because of their high resistance and the small amount of pressure which is available for forcing the contact points together. Of the metals suitable for contact points in relay controlled signal circuits, platinum is considered the best, but is objectionable because of the great danger of its fusing at the contact points during electrical storms, thereby preventing the opening of the signal circuit and showing a false signal in the clear po sition, indicating a clear track for a certain block when said track might be occupied by a train. I overcome the possibility of such a condition by providing an auxiliary circuit maker and breaker which in the event of the platinum contacts becoming fused,

will operate to open and close the circuit until the fault can be remedied, preventing the giving of false signals and maintaining the system in operative condition until the damaged contact is repaired.

Referring to the characters of reference, 1 designates the rails of a railway which are separated electrically into blocks by insulating material 2. Connected with each block is a track circuit 3 including a battery 4 or other source of electric energy, and including a relay or electro-magnet 5.

In illustrating the application of my invention, I have shown only so much of a block signal system as is necessary to con vey a correct understanding of the operation of my device.

Each of the electro magnets 5 in the track circuits of the several blocks provided with an "armature 6 mounted upon and extending between the parallel bars 7 pivoted at their rear ends on a yoke 8 upon a transverse pin 9. The forward ends of the bars 7 are connected by a transverse rod or pin 10 upon which is pivoted near its forward end the central lower bar 11 whose rear end is pivoted at 12 to the upper end of an angle lever 13, fulcrumed at 14 on a suitable support. The forward end of the lower bar 11 is pivoted at 15 to the upper face of the contact arm 16 having an upwardly bent end carrying a platinum contact point 17. The

rear end of the contact arm is pivoted at 18 in the yoke 8. Extending downwardly from the cross rod 10 is a curved finger 19 which engages under the contact arm 16 and normally supports said arm. Mounted in the case 20 of the relay, is a binding post 21 carrying one of the circuit conductors 22 of the signal controlling circuit. The lower end of the binding post carries a platinum contact plate 23 with which the point 17 engages to close the signal controlling circuit when the magnet 5 is energized, as shown in Figs. 2 and 6. Attached to the free end of the lever 13 is a platinum point 24 which dips into a glass cup 25 having mecury 26 therein. Electrically connected with the mercury in the cup 25 is the other electrical conductor 27 of the signal circuit, in which is included a battery 28. It will now be understood that the signal controlling circuit includes the mercury cup 25 and that the flow of current under ordinary conditions is through said cup. Connecting the lever 13 and the contact arm 16 is a conductor 29 for the purpose of insuring a more perfect electrical connection between said parts than might be afforded through the pivotal connections 14 and 18.

In the signal controlling circuit is a relay magnet 30 adapted to close at 31 the signal circuit proper 32 including a battery 33, or other source of electrical energy, and a suitable signal 34. The signal circuit remains closed while the magnet 30 is energized.

On referring to Fig. 1, it will be seen that under ordinary conditions, the track circuit 3 is closed through the magnet 5 maintaining said magnet energized and holding the signal controlling circuit closed at contact 17. Should a train enter a block, as shown at 35 in said figure, the track circuit will be short circuited through the wheels thereof, thereby cutting out the relay 5 of that block of the track, permitting the armature 6 to drop and open the signal controlling circuit at 17, thereby opening the signal circuit at 31 to display a signal that indicates the presence of a train in the block. Upon the passage of the train from the block, battery 4 will again energize magnet 5 and close the signal controlling circuit at 17, thereby energizing the relay 30 and closing the signal circuit at 31, restoring the parts to their normal position, as will be well understood.

Should the contacts at 17 become fused sufficiently to cause it to stick, the deenergization of magnet 5 through the presence of a train in the block, would not operate to open the signal controlling circuit at that point, and were provision not made for opening said circuit, the signal would indicate a false condition. The cup of mercury and movable platinum contact therein affords an auxiliary circuit breaker for the signal controlling circuit, in case the contact "shown in Fig. 9, thereby breaking the signal controlling circuit at that point. Upon the energization of the magnet 5, the armature is attracted and the bar 11 raised to actuate the lever 13 and carry the platinum point 24 again into the mercury, thereby closing said circuit, said device forming an auxiliary circuit breaker which will operate to close the circuit until the fused contact point 17 can be restored to its normal working condition, insuring a perfect operation of the signals at all times. Because of the fact that the mercury circuit opener and closer is seldom used, the contact point which dips into the mercury is practically always immersed therein, whereby it is kept free from oxidation and is therefore always clean and ready for use.

When the device is operated to open and close the circuit through the mercury contact, it will be noted that finger 19 drops away from the contact arm 16 upon the opening of the circuit, but reengages said arm when the magnet is energized, the presence of said. finger being necessary to a proper working of said instrument when the circuit is being opened and closed at the contact 17.

The shape of the mercury cup 25 is such that the mercury cannot be spilled therefrom, should the relay be turned over as the space 36 at the top of the cup is sufficient to hold the mercury and prevent it flowing out the reduced opening around the platinum contact 24 under such conditions, while the smallness of the aperture in the top of the cup through. which the contact passes, prevents any serious loss of mercury through evaporation. The cup 25 is made preferably of glass to enable its contents to be viewed at all times, and to provide insulation for the platinum contact 24 when withdrawn from the mercury so as to insure a perfect breaking of the circuit.

In Figs. 3 and 4, I have shown a slightly modified form of the circuit breaking apparatus, wherein the pivotal and fulcrum points of the bar 11 are transposed, causing the rear end of said bar to rise upon a release of the magnet 5 when the point 17 is fused, and to exert a direct upward pull upon the platinum contact 24 to withdraw it I from the mercury in the cup 25, as shown by dotted lines in Fig. 3.

In case the post not shown, which supports the housing in which the relay is mounted, should become broken, by a wreck or any occurrence which would cause such injury to the relay as to break it down, or throw it into a horizontal position, the signal controlling circuit would be opened to set the signal at danger by the flowing of the mercury from the platinum contact 24 should the mercury cup be placed in a hori- -zontal or in any other position except an upright one, in which case the device would serve as an emergency circuit breaker to call attention to the damaged condition of the relay and signal controlling circuit. This feature, however, of the mercury cup serving as an emergency circuit breaker, is more particularly described and claimed in my copending application for circuit breaker for automatic signaling apparatus, Serial No. 4:014:36.

It may be stated that the fusing of the main contact in the signal circuit is due to the imperfect electrical union between the plate and the point 17 because of lack of suflicient pressure to hold said parts firmly together, causing an are upon the passage of a heavy current. An arc does not occur at the mercury contact on the passage of a h mvy current through said parts, owing to the perfect electrical continuity of the circuit at that point.

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

1. In a signaling apparatus, the combination with an electro-magnet, of an armature carrying a contact, a signal circuit in which said contact is included, an auxiliary circuit opener and closer also included in said circuit, said auxiliary opener and closer consisting of a body of mercury, and a contact movably associated therewith, a cup of insulating material in which said mercury is confined, said cup being of such shape as to prevent the escape of the mercury should it become overturned, and means connected with the armature for actuating the auxiliary circuit opener and closer should the armature contact fail to open.

2. In a signaling apparatus, the combination with an electro-magnet, of an armature carrying a contact, a signal circuit in which said contact is included, an auxiliary circuit opener and closer also included in said circuit, said auxiliary opener and closer consisting of mercury and a contact movably associated, and means connected with the armature for actuating the auxiliary circuit opener and closer without movement of the armature contact parts, should the armature contact fail to open.

8. The combination with a relay magnet, of a movable armature, a signal circuit, a mercury circuit breaker in the signal circuit consisting of an insulating cup holding a body of mercury, and a contact movably associated therewith, said cup being shaped to prevent the escape of the mercury should it be overturned, and having a mercury receiving space of sufficient size to accommodate the body of mercury when inclined or in a horizontal position, the mercury when filling said space being free from said movable contact, and means for connecting the movable contact with said armature.

4. The combination with a relay magnet, of a movable armature, a signal circuit, a platinum contact carried by the armature to close said circuit, an auxiliary circuit breaker included in said circuit, said circuit breaker consisting of a body of mercury, and a contact movably associated therewith and movable parts connecting the movable contact of the auxiliary circuit breaker to the armature to cause an actuation of the auxiliary circuit breaker upon a movement of the armature.

5. In a signaling apparatus, the combination of a relay magnet, a movable armature, a signal circuit, a platinum contact carried by the armature to close said circuit, an auxiliary circuit breaker in said circuit consisting of a body of mercury and a movable contact operatively associated, and a movable member connecting said movable contact to the armature to break the signal circuit should the platinum contact become fused.

6. The combination with a relay magnet, of a hinged armature, a contact carried thereby, a body of mercury in an insulated receptacle, and a second contact remote from the armature contact but jointedly connected with the armature and actuated thereby, said contact being movably associated with and normally immersed in said mercury.

In testimony whereof, I sign this specification in the presence of two witnesses.

EDWARD A. EVERETT.

Witnesses:

E. S. WHEELER, I. G. HOWLETT.

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