US1935098A - Crossing signal - Google Patents

Description

Nov. 14, 1933.

B. D. NEWTON 1,935,98

CROSSING SIGNAL Original Filed Nov. 5, 1923 3 Sheets-Sheet 1 f/W EN roe flwezs rr 0. NEWTON,

Nov. 14, 1933. B. D. NEWTON 1,935,098

CROSSING SIGNAL Original Filed Nov. 5, 1923 3 Sheets-Sheet 2 //v l/E/V TO/E. flue/(Err Q NEWTON) fly WM HT Toe/v6 X B. D. NEWTON CROSSING SIGNAL Nov. 14, 1933.

3 Sheets-Sheet 3 Original Filed Nov. 5, 1923 ATTQQ/VEY,

Patented Nov. 14, 1933 pairs tenses CROSSING SIGNAL I Burliett D. Newton, Southlasadena, Oalif., as-

signor to Magnetic Signal Company, Los Ari-'- geles, Calif., a'corporation of California Continuation of application Serial No. 672,841, November 5, 1923. This application September 15, 1928. Serial No. 306,112

Claims. (O1. 177+329) This application is a'continuation of my application entitled AuXiliary crossing signal, Serial No. 672,841, filed November 5, 1923.

My invention relates to railway crossing sig- 5 nals and is particularly applicable to what has become known in the trade asfwigwag flagmen. These signals are usually constructed with a round target which is hung as a pendulum from suitable mechanism andelectrically illuminated and oscillated whenever a train approaches a highway crossing which the signal is set to protect. Usually a loud gong is also simultaneously put in action, so that the'driver of a vehicle approaching the crossing on the highway is warned by the swinging target, thered light in the signal and by the gong. While my invention may be applied to other forms of signal, it has a special utility in connection with a wigwag flagman, which is the standard form of signal now in .0. general, use throughout the United States.

Wigwag signals aremanufactured and sold by several concerns and have been developed to a high degree of reliability. They are usually electrically operated byprimary batteries. It is, of course; essential that any signal of this character be highly reliable, since due to the congestion of the highways with automobile traffic, any failure ofthe signal to properly function may result in fatal accidents. In spite of the best efforts of the designers of such signals and of the operating stalls of the railroads maintaining them, signal failures will occur. 1 v y y y I To guard against; or perhaps we should say, to neutralize these-failures, the so-called three position signal has been adopted. Such a signal may consist of the usual wigwag llagman which at rest indicates safety and in motion indicates danger, plus means for producing a third position indicating that the signal is out of orders v For examplea shield may be provided behind which the target of the wigwag is retired to indicate safety. Such three position signals are in limited use, but involve certain modifications of the standard wigwag which increase their liability to failure. They are also objectionable in that the out-of-order position is not of such" a nature as to be instinctively'understood by the public. In other words, a truck driver does not instinctively understand that because the target is not behind the shield but is hanging down, the signal is out of order and he must exercise great caution in crossing the railroad tracks.

It is an object of my invention to provide an auxiliary signal which can be added to or used with thestandard form of wigwag fiagman, without detracting from the reliability of the flagman, and which will give an out-of-order indication which will be readily understood by an person approaching on the highway;

The failure of an electrically operatedv signal to operate usually arises from one of two causes. It may fail due to a failure of the signal to get an adequate supply of electric current. Such a fail: ure may be called electrical; Or it may fail due to some mechanical defect or failure in the signal proper. Such a failure may be called mechanical. t

It is a further object of my invention to provide an auxiliary signal which gives an out-of-order. indication upon either an electrical 'or a mechanical failure of the main signal with which it is used. 1 It is a further bject o'f my invention to provide an auxiliary signal which can be readily and efiiciently applied to the standard form of wigwag flagman,

' i It is. a further object of my invention to provide an'auxiliary signal which will give an outof-order indication upon electrical or." mechanical failure of the-main signal and which will also automatically reset into its non-indicating positionupon-removal of 'the cause of such. failure. Y Y v It is also an object of my invention to provide an auxiliary signal having the properties above described which will have a definite time element so that it will not respond to transient conditions.

Further objects and advantages will be disclosed hereinafter.

Referring to the drawings which are purely forillustrative purposes,

Fig. 1 is an elevation of a wigwag fiagman and an auxiliary signal as seen from the highway with both signals in their normal or,safety position I v Fig. 2 is a similar view withthe auxiliary signal indicating out-of-order. I i Fig. 3 is a side elevation, on a larger scale, of the auxiliary signal. Fig. 4 is a side elevation, on a still larger scale, of the reset mechanism. Fig. 5 is a front view of that mechanism. Fig. 6 is a side elevation of the tripping mecha-- nism. v

Fig. 7 is a section on a plane indicated bythe line 77 of Fig. 6 viewed in the direction of the arrows adjacent to that line.

Fig. 8 is a diagram of connections. Fig. 9 is a section on theline 99 of Fig. 8. 110

j energized and to alternately attract an armature 16 carried by a shaft 17. The shaft 1'7 carries a switch mechanism 19 and a target 20 which is waved when the wigwag operates.

The switch 19 may be of any well known design used to alternately energize coils in the wigwag.

The switch 19 as shown is similar to the switch shown in the prior art patent to Morse, No. 1,356,- 875, patented October 26, 1920. Depending from the shaft 17 is a flexible finger 21, which is flexed by a guide 22 into contact first with a contact 23 and then on an opposite oscillation of the wigwag into contact with a contact 24. A complete description .of the details of construction and operation of the switch 19 may be read in the Morse Patent No. 1,356,875.

Mounted on the knee braces 13 is an auxiliary signal 25. This signal consists of an arrow 26 pivoted on a shaft 26a and normally obscured, as shown in full lines in Fig. 3, in a case or shield 27. The arrow 26 preferably has the words Out-of-order printed thereon, and it may be provided with a red disc or light 265. The arrow 26 is so weighted that it naturally tends to fall into the out-of-order position, as shown in Fig. 2 and in dotted lines in Fig. 3.

The tendency of the arrow 26 to'so fall is resisted by a hook 28 rigidly attached to the arrow 26, and so placed as to be engaged by a latch 29 pivoted at 29a on a member 30 carried inside the case 27. The latch 29 is provided with a keeper 31, which is caught and held by'two cores 32, forming part of a complete magnetic circuit, of which the keeper 31 is a part. Wound upon each of the cores is a coil 33. Each of the coils hasa continuous copper jacket 34,, (shown in Fig. 7) and wound outside each of the jackets 34 is a coil 35. I g

' The magnetic circuit is normally energized by the coils 33 and the parts are held in the position shown in Fig. 3. When, for any reason, the magnetic circuit is deenergized, the latch 29 releases the hook 28 and the arrow 26 falls into its out-of-order position.

For the purpose of returning the arrow from its out-of-order position, as shown in dotted lines in Fig. 3, to its set position shown in full lines in that figure, I employ a reset mechanism consistingof coils 40 surrounding a reset magnetic circuit, of which an armature 41' is a part. -This armature is attached to the arrow 26 and is pulled from the position shown in full, lines in Fig. 4 into the position shown in dotted lines in that figure, by the attraction of pole pieces 42 forming a part of the reset magnetic circuit, this attraction. being due to the-magnetic field caused by electrically energizing the coils 40 which surround the pole pieces 42. A finger 45 is secured in, but electrically insulated from, the case 2'7 and presses upon a segment 46 secured to, but electrically insulated from the arrow, 26. The segment 46 is'of such length that electrical contact between it and the finger 45 is broken as the arrow reaches its resetposition, shown in full lines, in Fig. 3.

The method of electrical interconnection of the main and auxiliary signals is shown in Fig. 8. Electrical energy is supplied from a suitable source, not shown, such for example as primary batteries. The current is supplied through wires 50 and 51. A circuit is completed, upon the approach of a train, between the wire 51 and a wire 53 by a track relay 52 in accordance with standard practice in wigwag flagman operation.

The coils 33 are permanently connected in series with each other, across the wires 50 and 51, and are fully energized at all times that the voltage of the electrical source is normal. Any failure of the electrical source or in the conductors 50 and 51 deenergizes the coils 33. The coils 35 are connected in series with each other and, through the coils of a cut-out relay 55, with the wire 53. The relay 55, when energized, opens the circuit through the coils 40 and this circuit is also opened at the'segment 46 just before the arrow 26 snaps into its set position, as shown in full lines of Fig. 3. The other terminal of the coils 35 is connected to the guide 22. It is not imperative for the coils;35 to be connected to the guide 22 and theyrmaybe connected to contacts 56 which are engaged by a finger 5'7 which is separate from the switch 19.

- The'flexible arm in Fig. 8 is held in engagement with the contact 23. When the, circuit is closed by a train, the coil 14 will be energized and the target swung to the right. On the return stroke the guide 'will cause the finger 21 to engage the contact 24 with the result that the coil 15 is energized and the target swung.

to the left.

The method of operation of my invention :is as follows:

If the signals are in normal condition, they will be in the position shown in Fig. 1. In this position the arrow 26 is held inside the case 2'7 by the holding coils 33 which are continuously energized. In this condition the signal 10 will operate in the standard manner whenever the coils 14 and '15 are energized'by the relay 52.

If for any reason, however, there has been a previous failure of the signal, the parts will be in the position shown in Fig. 2. In this position the arrow 26 points to thet'arget 20 and clearly notifies highway trarhc that the signal 10 is out of-order.

' If, however, at any time the'faulty condition is remedied, the auxiliary signal instantly resets. This is accomplished due to the flow of current from the wire 50 through the finger 45 to the segment 46, through the normally closed contacts of the relay 55, and through the coils armature 41 down and throw the arrow 26 up into its concealed or safety position. The eir cult through the coils 40 is broken, just before the arrow reaches its set positiongby the finger other causes. If the coils 33 are deenergized,

the. magnetic circuit set up thereby is broken to the wire 51. The energizing or" the cells 40 magnetizes the pole pieces 42, which pull the and the armature 31 is released. This releases 7 in this position until the potentialis restoredthe coils 35.

coils 40 before the signal can reset.

between the'wires 50 and 51, at which time; the signal resets as'explainedabove. 1

Mechanical failures are failures of the main signal 10 to operate,'although full potential is supplied between the wires 50 and 51. It may, for example, be'due to mechanical failure of some part so that the target 20 fails to oscillate. It may also be due to an electrical failure in the coils 14 or 1", or broken circuit in the wigwag signal mechanism, any one of which, excepting the circuit including the coils '33, would prevent the target from operating. Such a failure might be termed. a mechanical failure, since it prevents the target from operating. If this occurs with the target 20 in its normal, or central, inactive position-or at any position of the targets travel, the flexible finger 21 makes contact with the guide 22, and the circuit including the coils 35 is energized. The coils 35 are-wound to neutralize the coils 33 and thus deenergize the magnetic circuit setup, thereby thus releasing the armature 31 and allowing the arrow 26 to fall into the outoforder" position. The switch 19 may therefore be considered as a mechanical failure switch since it operates to release the' arrow 26 when a mechanical failure occurs.

If the mechanical failure switch shown in Fig. 10 is used, the finger 5'? will engage one of the contacts 56 to close the circuit which includes The armature 16 is, however, in its normal or central position whenever the cycle of operations start. 7

To prevent the auxiliary signal from operating whenever the relay 52 operates, it is necessary to provide a time delay element which is accomplished by the interposition of the soft copper sheath 34 between the windings 33 and 35. Whenever there is any tendency for the magnetic flux set up by the coils 33 to decrease, eddy or circulating currents are set up in the sheath 32 which resist this tendency of the flux to decrease. The result isthat a momentary energizing of the coils 35 will not greatly affect the flux and the finger 21. breaks circuit with the guide 22 before the flux falls enough to release the armature 31. This allows some delay in the movement of the mechanism of the signal 10 without dropping the arrow 26 to its out-oforder position. In practice the parts may be so proportioned that the armature 16 -must remain substantially stationary for ten seconds before the out-of-order indication is given.

At the same time that the coils 35 are energized the relay 55 is energized, which opens the circuit to the reset coils 49. As long as the relay 52 is set to operate the signal and the mechanical failure persists, the relay 55 remains open, thus preventing the resetting of the arrow 26 to its safety position. The opening of the relay 52 deenergizes the coils of the relay 55 and prevents loss of energy therein. Whenever the contacts of the relay 52 close and full potential exists between the wires 50 and'51, the relay 55 operates very rapidly, thus cutting out the reset This prevents the repeated resetting and-releasing of the arrow 26, when the relay 52 closes, and there is a mechanical failure but no electrical failure.

It will be noted that the case 25 can be readily and inconspicuously attached to the knee brace 13, now commonly used to support the arms 11 of the standard wigwag and that by using the contacts 23 and 24 and the arm 21 which now exists, the auxiliary signal can be interlocked with the standard wigwag and operated therewith. It can, therefore, be made a part'of the initial installation or added to existing-signals without much labor. The most'comrnon types of failure are probably electrical, that is, they are due to a failure to maintain a suflicient potential between the wires 50 and 51. Any such failure instantly sets the out-of-order signal. We are not, however, limited to failures of this class but trip our arrowv 26, if for any reason after current is appliec the target 20 does not start to swing and continue to swing thereafter as long as the relay 52 holds its contacts closed. If, for example, he 21 dwells on any of the contacts 23 or 24 for. an interval of more than a few seconds, the arrow 26 drops. This covers every possible contingency except a mechanical destruction of the auxiliary signal itself, which contingency is so remote it may be disregarded.

When soinstalled, it does not in any way in terfere mechanically with the operation of the standard wigwag which operatesiin its usual efficient manner. The auxiliary signal, therefore,

does not increase the liability of failure of the instantly understood. The arrow 26 has, therefore, a very high warning value.

My invention, therefore, provides means for making the present standard wigwag fiagman absolutely certain and reliable in its indication, whether in operating condition or not, in that it does not interfere in any way with its normal operation and instantly gives highway traffic notice of any abnormal or outoforder condition of the flagman. Y

I claim as my invention: 1. In combination: a wigwag signal; asource of, energy for operating said wigwag signal; an

out-of-order signal having an indicating and anon-indicating position; latch .means for normally holding said out-of-order signal in nonindicating position; reset means for returning said out-of-order signal to non-indicating position; means for causing said latch means to release said out-of-order signal when a mechanical failure in said wigwag occurs; and means preventing the operation of said reset means so long as said mechanical'failure continues.

2. In combination: a wigwag signal; an outof-order signal having an indicating and a non- 7 indicating position; means for supplying energy for operating said signals; latch means for releasably holding saidout-of-order signal in nonindicating position; reset means for moving said out-of-order signal from an indicating to a nonindicating position; electrical means for releasably holding said latch means in latching posi-- tion; means for operating said electrical means to release said latch means upon a mechanical failure of said wigwag, 'said electrical means also releasing said latch means upon an electrical failure; and means rendering said reset means inoperative during the continuance of said mechanical failure. 4

3. In combination: a wigwag signal; an outof-order signal having an indicating and a nonindicating position; means for supplying energy for operating said signals; latch means for releasably holding said out-of-order signal in nonindicating position; reset means for moving said out-of-order signal from indicating to non-indicating position; and means rendering said reset means inoperative upon a mechanical failure of said wigwag signal or upon afailure of said source of energy.

4. In combination: a wigvvag signal; an outof-order signal having an indicating and a nonindicating position; electrically-operated latch means for holding said out-of-order signal in non-indicating position; means operable upon a mechanical failure of said wigwag signal to operate said electrically-operated latch means and release said out-of-order signal, said electricallyoperated latch means releasing said out-of-order signal upon an electrical failure; reset means for moving said out-of-order signal from an indieating to a non-indicating position; andmeans rendering said reset means inoperative during the continuance of said mechanical failure.

5. In combination: a wigwag signal; an out of-ordersignal; a source of energy for operating said signals; latch means for holding saidoutofv-order signal in non-indicating position; electrical means for holding said'latch means in latching position; a means for neutralizing said electrical means upon failure of said wigwag to operate when energized, said electrical means releasing said latch means upon failure of said source of energy; reset means for returning said out-of-order signal to a non-indicating position; and means preventing the operation of said reset means so long as said Wigwag signal fails to oper ate when energized. l l

BURKETT D. NEWTON.

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