US1720644A - Train control - Google Patents

Description

FIG].

|AS|c July 9, 1929.

F. 1.. DODGSON 1.720.64

TRAIN CONTROL Original Filed Jan. 28, 1924 5 sheets-Sheet l I IN E NTOR. Q 5?- r ATTORNEY H F. L. DODGSON TRAIN CONTROL Juli} 9, 192 9.,

Original Filed Jan. 28; 1924 5 sheets-sheet 2 I N V EN TOA.

F. L. DODGSON TRAIN CONTROL Jul 9, 1923.

5 Sheets-Sheet 3 Original Filed Jan. 28, 1924 MNVENTOR.

July 9, 1929. F. DODGSON TRAIN CONTROL 5 Sheets-Sheet 4 Original Filed Jan. 2 8, 1924 i L!!! dill/P3 July-9, 1929. F. L. DODGSON TRAIN CONTROL Original Filed Jan. 28, 1924 5 Sheets-Sheet 5 mmm mi m8 Patented July 9, 1929.

with; STATES I men Pl @FEQE.

FRANK L. DODGSQ N, OF ROCHESTER, NEXV YORK, ASSIGNOR 'IO GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW YORK.

TRAIN CONTROL.

This invention relates to train control systems, and more particularly to means for stimulating the vigilance of the engineer and his obedience to the wayside signals, and for inflicting a penalty if the engineer does not manually apply the b 'akes before the speed of the train is excessive.

In applying automatic train control apparatus to railroads it is considered desirable to employ such apparatus as an additional safeguard over that obtainableby a careful, alert and prudent engineer rather than as a substitute for such engineer. In other words, it is desirable to have the safety 5 of the train depend on both the automatic train coi'rtrol apparatus and the engineer, rather than either of these two standing alone. Also, in applying automatic train control apparatus which limits the speed of the train (speed control systems) as distinguished from a system which stops the train depending alone on traflic conditions ahead (automatic stop systems) it is found ditiicult to determine what the safe speed at which a train may run at the various points in a block is when the next block in advance is occupied, especially as the blocks are different in length, have different grades and curves, or the like. lVith the above and other considerations in 3Q) mind it is proposed in accordance with the present invention tojset up arbitrary speed limits at various points in a block which are on the side of safety,'and .are suitable speed limits at which all trains may safely run,

even though perhpas less than the safe speed limits for certain trains; and to provide means for inflicting a penalty if an automatic brake application occurs because the train passes such a point at a speed in excess of the arbitrary speedliiuit unless the engineer has anticipated such automatic brake application by initiating a manual application. Another object and feature of the present invention contemplates the provision of a simple and direct way of determining when an adequate brake application, such as the usual service application, has been effected so far as manual control is concerned, it being desirable to know if an adequate brake application has 59 been initiated and will take place, because a certain amount of time transpires between the completion of the manual control of a brake application and the brake application itself, this determination or manifestation of the.

. as .ap n opriate in. nnal. control of a brake appli Application filed January 28, 1924, Serial No. 689,020. Renewed July 30, 1927.

cation continuing only so long as the manual control is undisturbed and in time will consummate the brake application. More specifically the proposed apparatus inone form includes a time element device, or clockwork 60 mechanism, which is adapted to suppress the action of a penalizing means providing the engineer has had the usual engineefis brake valve in the service brake applying position for a predetermined interval of time and has not in the meantime returned the brake valve to the running or release position.

Other objects, purposes and characteristic features of the invention will appear as the 7 description thereof progresses.

In describing the invention in detail reference will be made to the accompanying drawings in which Fig. 1 shows the trackway equipment of a train control system of the continuous inductive type, a portion of the car-carried equipment being shown, and speed restricting and train performance curves of a particular block to which the present train control apparatus is applied being illustrated;

Fig. 2 illustrates in a diagrammatic and conventional manner the car-carried equip ment of the train control system just referred to;

Fig. 3 illustrates a car-carried system simi- 5 lar to that shown in Fig. 2 (portions thereof being omitted) employing a modified circuit arrangement for the penalty suppressing apparatus;

Fig. 4t illustrates a car-carried system such as shown in Fig. 2 employing a modified type of penalty suppressing means which does not include a clockwork mechanism;

Fig. 5 illustratesa train control system of the inductive intermediate time-distance in- 'terval type employing a penalty suppressing arrangement including clockwork mechanism; and

Fig. 6 shows the car-carried apparatus of the system as shown in Fig. 5 including a penalty suppressing means similar to that shown in Fig. l.

The specific embodiments of the invention as illustrated in the drawings consist of a novel arrangement for penalizing the engineer if he does not attend to his duty as ap plied to two distinctive types of systems,

nan'iely, (1.) train control system of the continuof inductive type as illustrat d in Figs. 1, 2, 3 and. at; and (2) an intermittent speed no control system of the time-distance interval type as shown in Figs. 5 and (3.

Continuous system.

Traclmoay (LP}P(I/I(ZZ 'L(-t'.-IH Fig. 1 there have been illustrated the usual track rails 1, divided by insulating joints 2 into blocks in the usual manner, only the block I and the adjacent ends of two other blocks H and J being shown. Since the various blocks are the same, like parts of each block have been (.les'ignated bylike reference characters having distinctive exponents. Although the train control system embodying the present invention may be used in connection with wayside si'gi'ials of any type, such as semaphore signals, position light signals and color light signals, it has for convenience been shown applied to a system employing sei'naphore signal Z, which have been shown conventionally without illustrating any particular form of their well-known control circuits and control mechanism.

Each of the blocks is provided with a suitable source of alternating current energy at the exit end thereof, illustrated as a track transformer 3, and a suitable track relay 4 at its entrance end. T his forms the well-known closed track circuit which needs no further discussion.

Inaddition to the usual track circuit current flowing in the rails of a block, there is provided a circuit to permit the flow of alternating current in the two rails in multiple in 7 the same direction, which for convenience will hereinafter be referred to as the simplex circuit. In order to permit the flow of cur rent in this simplex circuit, including in multiple the rails of a portion of a block or the rails of the entire block, three balancing resistances 5, 6 and 7- are bridged across the rails at the entrance, at an intermediate point, and at the exit end of each block respectively. In order to supply alternating current energy to these two circuits, a transmission line including wires 8 is strung along the track, the energy for the simplex circuit of each block being supplied by the transformer 9.

In order to cause the simplex current to flow in one particular direction as compared with the direction of How of the loop circuit or track circuit current along the entire length ofthe block at one time, and cause it to flow in the opposite direction through a portion of the block only at other times, front contacts, as 12 and 13 operated by the track relay of the block next in advance, as l are provided. Referring to the block I, by looking at the circuits governed by these two front contacts 12 and 13 it is readily apparent that if the track relay 4 is in its normal energized condition, current is permitted to flow through the two rails in mul tiple in the block I from the middle point of the balancing resistance 7 to the middle point of the balancing resistance 5, and that when this track relay l dcenergized, current will flow in a reverse direction from the middle point of the balancing resistance 5 through the tworails in multiple to the middle point of the balancing resistance 6 located at an intermediate point in the block. In practice the constants of these simplex circuits with respect to the constants of the loop circuit including the track transformer are so chosen that the phase displacement between these two currents is as large as possible or practical, so that if these currents are detected by suitable apparatus on the train, that is, amplified and applied to a two element or three position relay, this, relay produces a torque in one direction or the other depending on the phase relation between these two currents and in turn on the position of contacts 12 and 13 of the track relay ahead.

Influence co'nmmaicating means-On the vehicle, which has been conventionally shown by axles l5 and wheels 16, is a pair of loop or track circuit influence receiving elements LE, comprising cores 17 terminating in pole pieces 18, each having a winding or coil .19 thereon. in a manner so that the voltages induced therein, due to currents flowing in the opposite direction in the two rails, are cumulative, and these coils are connected to a suitable amplifying devicecAL (not shown in detail) which comprises thermionic or vacuum tub'e amplifiers of well-known commercial or special construction. The output lead wiresof this amplifying device AL are connected to the winding LR of the control re lay B.

At a suitable point on therailwa'y vehicle is a simplex element SIC, which comprises a long core 20 terminating in enlarged pole pieces 21 and having a coil 22 thereon for detecting the how of simplex current in'the two rails in multiple. This coil 22 is connected to the input side of a similar amplifying device AS which has its output terminals connected to the other winding SE of the control relay It. It is thus apy iaren't that, with currents flowing in the loop circuit ahead of the train and in the simplex circuit under the train ha ving a certain phase displaccn'ient, currents will be supplied by the two amplifying devices AL and AS of a similar phase relation and will cause the relay It to be operated in a certain direction, and that, if one of the track currents has its relative current flow reversed, the control relay It will be operated The coils 19 are connected in series magnet CSL of a suitable speed restricting apparatus to be described hereinafter, the currents for energizing these two magnets being derived from a suitable source of energy such as a battery. The battery is not shown, but B designates a connection to one terminal, and C a connection to the other terminal.

Train performance speed chara0terist2'0s. Directly over the block I of the trackway shown has been illustrated a solid line curve 23 which shows the permissive speeds at which the train may run without exceeding the speed limit set up by the car-carried apparatus to be described hereinafter. It will be noted that this curve has a drooping characteristic in the first part of the block I, eontinues as a straight line corresponding to a constant speed for a distance, and then again droops until it reaches a low constant speed limit of miles per hour. Thefirst droop in the curve is caused by the high cam to be described hereinafter, and the second droop in the curve is due to the low cam. The particular block I in connection with which these curves have been shown is assumed to be either va clown-grade block or a block in which the braking ability of the train is poor for some other reason, and therefore requires a longer distance of movement to bring the train to a certain value than the distance in which one or the other of these cams run from a maximum to a minimum speed posit-ion.

The dot-and-dash line 24 illustrated shows the speeds of the train at different points along the track if the brakes are applied when the train enters the block I at a speed of about 65 miles per hour. .It is thus noted that, with the character of block assumed, even though the engineer does apply the brakes upon entering the block I, he will be unable to stay below the permissive speed line set up by the high cam, this being shown by the fact that the dot-and-dash performance curve 24 crosses solid permissive speed curve 23 at the point 25. Also, if the engineer releases the brakes when he gets below l0 miles per hour limit, and proceeds at a constant speed until he reaches the point X in the block, he will not be able to stay below the permissive speed curve enforced by the low cam, even though he applies the brakes when passing the pointX, as illustrated by the fact that the dotand-dash performance curve .24; crosses the solid permissive speed curve 23 at the point 26. The continuation of the first droop in the dot-a-nd-dash line 24 has been shown by a dotted line 27 which illustrates the speed at the various points in the block that the train assumes if the brake application is continued, that is, shows the brake performance curve for a complete stop from high speed. It should be understood that the particular speed-distance curves illustrated apply only to the particular set of conditions which have been assumed in order to bring out certain advantageous features of the present invention, and that these curves are notnecessarily characteristic of train performances for all trains in all blocks or portions of the railroad. The speed-distance curves of permissive speed and train performances are merely typical and are not intended to be accurately shown, being susceptible to'wide variation in practice to conform with the different speed limits required for different kinds of equipmentand varying practices on railroads.

Oar-carried apparatus 0 f Fig. Z.

Penn/{satire and actual speed 77260]t(l7lx2ih'771-.

Since the high cam and low cam operating mechanisms are substantially the same. except to the particular shape of the cam and the speed limit enforced, the high cam and its associated mechanism only has been illustrated. The influence communicating apparatus for controlling both the high and the low cam has already been referred to, and is shown in 1, the cam starter magnet CSH of this apparatus being shown in Fig. 2. On the vehicle l5 l6 a shaft 30 driven by the wheels of the vehicle in a suitable manner. Qn this shaft 30 is a worm 31 meshing with a worm wheel 32 which through reduction gears 33 and 3st drives a pinion 35 pivotally secured in the bifurcated end of an arm 36 which is pivoted about the axis of the gear 34-, so that the pinion 35 may be moved into or out of engagement with a mutilated gear 37 without disturbing its meshed relation with the gear lhis g'ear 3'? is pinned to a cam shaft 88 having a cam 39 fixed thereon. The arm 36 is urged upwardly by a compression spring 4-1, disposed around a guide 4-2, so that if the cam starter magnet CSH is deenergized the pinion 35 is urged upward into meshed rela tion. with the mutilated gear 37, whereupon movement of the vehicle along the track gradually turns the cam shaft 38 and its associated cam 39. In order to return the shaft 38 back to its normal position in the event that the cam starting magnet CSH is again energized, a gear sector 43, pivoted at 4%, engages a pinion i5 on the cam shaft 38; and this gear sector 43 is biased to an intermediate position by initially tensioned springs 4:6.

011 the shaft 30 is mounted a centrifugal speed-responsive device G of usual and wellknown construction. which comprises a collar 47 pinned to the shaft 30, another similar but grooved collar 48 slidably mounted on this shaft, these collars being coupled together by links L9 having a weight 50 at their pivotal junction, and a compression coil spring 51 between these collars.

Parallel and preferably adjacentto the 'shaft 38 is a speed shaft 53 to which is pinned a bifurcated arm 54 engaging the groove in the collar 48. Pinned to this shaft 53 a speed arm 55 and a speed cam 56. An increase in the speed of the sh aft causes the collar 4:8 to move in response to the centrifugal force acting on the weights 50 in opposition to the spring 51, so that the speed shaft 53 an d speed arm 55 and the speed cam 56 are moved in a clockwise direction. To the lower and free end of the speed arm, 55 is pivotally secured one end of a floating lever 57 which carries a roller at its other end engaging the cam surface oi he cam 39. At an intermediate point on thefloating' lever 57 is pivotally secured one end of a link 58 which has its other end pivotally secured to an eccentrically located pin on the sector 59, which sector is pivotally supported on a pin 60. Adjacent the sector 59 secured a spring linger ()1 which has a roller 62 pivotally secured thereto which rides on the cam surface of the-sec tor 59. This spring); linger 61 normally cooperates with a stationary linger 63 to control a suitable circuit more clearly described hereinafter. Adjacent to the speed cam 56 are provided similar contacts 64 and 65 which cooperate with this cam 56.

By looking at this structure it will be readily understood that the sector 59 will move in a clockwise direction in response to moven'ient' of the cam 39 from its normal position. It will also appear that this sector 59 moves in the same or clockwise direction in responseto an increase in the speet as indicated by the governor G, so that either an in crease in speed or movement of the cam 49 from its normal position tends to move the sector 59 in the same direction and eventually allows the roller 62to ride into the contracted or reduced portion of this sector, thereby opening the contacts 6163. In other words, after the cam 39 moves from its normal position, the speed of the train must be correspondingly reduced to avoidopening of these contacts. Also. it will be noted that decreasing the speed of the train to a certain value, assumed to be two miles per hour, causes the cam 56 to close a circuit at the contacts 64; and 65 for reasons more clearly de scribed hereinafter.

Brake apply 510g deoicc.-The present train control system assumes the provision of means to automatically apply the brakes of the train under certain conditions of the can carried apparati'ls. In order to accomplish such a brake application, a brake z'q'i ilying device has been illustrated convention ally by the electro-pneuIna-tic valve EPV. This device EPV may vent the brake pipe directly, may operate a suitable engineer-s brake valve actuating means, or may control a suitable pneumatically operated brake applying device which vent-s the brake pipe to a predetermined eXtent and at a predetermined rate.

Since the applicability of any one of these of the present invention will be obvious and requires no specific showing, further description of this apparatus is deemed unnecessary.

The usual engineers brake valve has been shown conventionally, and is provided with a handle 66 and with suitable contact sectors 67, 68 and 69 which are adapted to close circuits in various positions of this valve as shown by the legends adjacent tothese seg ments in the drzuvings.

Directly below the engineefls brake valve is found a cut-out cock or doubleheaded cock in the usual air brake system, which has been conventionally shown by the cook 70 which is provided with a contact sector 71 which bridges the stationary contacts 7 2 when this valve is open, for purposes more clearly set forth in connection with the operation of the system.

Time? or clockwork meohaaism.ln order to suppress the penalty more clearly referred to hereinafter, it is desirable to close certain contacts, providing the engineer h had his brake valve in the service position for a certain period of time and has not thereafter moved it to either the running or the release position, and in order to control such a contact a suitable clockwork mechanism GM has been shown. This clockwork mechanism comln'is'es an escapement including a pallet 7 5 having headed screws 76 in opposite ends thereof which may be adjusted to change the moment of inertia of this pallet about its pivot 77, and consequently the period of oscillation of the pallet. This pallet is oscillated by an escapement wheel 78 which is driven through a gear train as shown terminating with a. gear-'79 connected to av shaft 80 through a ratchet wheel 8]. and a dog 82, said dog being urged into engagement with said ratchet wheel by a spring 83. On the upper end. of the shaft 80 is fixed a projecting arm Set having at its end apiece of insulation adapted to engz'l ge and close-contacts and 235 when said arm is moved to its extreme position.

Pivotally mounted and loose on this shaft 80 is a gear 86 which meshes wit-h a rack 87 connected to a piston 88 in a cylinder 89. This rack 87 and piston 88 are normally held in the extreme right hand position shown by a compression coil spring 90 within the cylinder 89. The shaft 80 is operatively connected to the gear 86 by aspiral spring: 91 for one direct-ion of movement, and is directly coupled to the shaft 80 for the other direction of movement of the gear by engagement of the pin 92, which anchors one end of the spring 9l-to the shaft 80, with a pin 93 fastened in: the gear 86.

Pressure is adapted to, be applied against the piston 88 by connecting the cylinder 89 to the main reservoir pressure of the air brake system by an electrically operated valve EV. This electrically operated. valve EV of usual and Well-known construction and includes two valve members 94 and 95 which are adapted to connect this cylinder to at1nospheric pressure or main reservoir pressure respectively, the valve 95 normally being closed by the action of the compression coil spring 96. In the upper compartment of this valve EV is an electro-magnot of the usual ironclad type, including an armature 97 and a Winding 98. If this winding 98 is energized, the valve 94 assumes the closed position and the valve 95 the open position, and main reservoir pressure flows into the cylinder 89. The flow of air pressure into the cylinder 89 moves the piston 88 to the left, thereby moving the pin 93 away from the pin 92, and simultaneously tensioning the spring 91. Under this condition of the apparatus the pallet 7 5 will be rocked back and forth in response to the torque on the escapement wheel 78 thereby slowly allowing the arm 8% to move in a clockwise direction and close the contacts 85 and 235 after a certain period of time, which is assumed to be about 6 or 7 seconds. This time interval, for which the clockwork mechanism CM is adjusted, is intended to correspond with the time required to vent the regular equalizing reservoir of the air-brake system through the engineers brake valve enough to cause a full service brake application, or such other application as the permissive speed limits require. If the electrically operated valve EV is again doenergized to allow the pressure to escape from cylinder 89, the spring 90 moves the rack 87 toits normal position and causes the pin 93 to engage the pin 02 and turn the shaft 80 back to its original position, this being permitted through the dog and ratchet engagement be-' tween the gear 7 9 and the shaft 80.

Operation.

Normal clam" 00mZri0n-9.-Under normal clear traffic conditions both the high and the low cam-assume their highest speed position whichcorresponds to the maximum permissive, speed limit, assumed in this case to be miles per hour, as shown by the curve 23 in Fig. 1. Assuming that the speed of the train' is less than this'value, which it is assumed to be as shown by the positions of the various devices in Fig. 2 of the drawings, the electro-pneun' atic valve EPV is energized by a stick circuit which may be traced as follows Beginning at the terminal B of a suitable source of energy, wire 100, contacts (l1 and 63, wire 101, winding of the EPV, wires 102 and 103, front contact 10% of the EPV, wire 105, back to common return 7 wire C. r i p r This circuit maintains the valve EPV in its normal inactive position, allowing the 'rain to proceed in accordance with the manner in which it is governed by the engineer.

If the engineer should allow the speed of the train to exceed the maximum limit of 65 miles per hour, the action of the governor G through the speed arm 55 causes contacts G1-63 to open, thereby interrupting the stick circuit for the EPV and applying the brakes of the train. lVhen the speed of the train has been reduced to, say, less than 2 miles'per hour, the contacts 64. and 65 close, thereby closing a pick-up circuit for the EPV, comprising wire 100, contacts 61 and 63, wire 101, winding of the EPV, wires 102 and 106, contacts 65 and 64:, wire 107, back to common return wire C. The completion of this circuit again picks up the EPV and this permits the engineer to release the brakes manually if he so desires. This requirement of bringing the speed down to practically a stop after exceeding the maximum speed limit, before the brakes can be released, is considered to be a penalty, and is assumed. to make him more vigilant in the control of the train to avoid such a brake application and penalty.

The penalty above described for exceeding the maximum speed limit is optional; and if desired, by a rearrangement of the circuits which will be very evident, this penalty may be omitted so far as the maximum speed limit is concerned, by making the electro-pneumatic valve EPV non-stick for clear traffic 2 is moving in the block H in the normal di- I rection of traffic as indicated by the arrow, and that the block J is occupied by another train. lVith the block J occupied, the track relay 4 is deenergized, thereby causing the simplex circuit between the entrance to the block I and the point X to be reversed. Consequently, when the following train in question enters the block I, the control relay R will swing to the reverse position, thereby deenergizing the high cam starter magnet CSl-l', but maintaining the cam starter magnet CSL energized. The high cam 89 is thus initiated and is gradually rotated in one direction or the other, depending on whether thereby gradually reducing the permissive speed, as indicated by the curve 23 in liig. 1. If the actual speed of the train does 'not exceed the permissive speed limits at any point, no automatic brake application will take efthe train is running pilot or tender first,

feet, it being assumed for the present that the permissive speed limits as indicated by the line 23 are not exceeded.

.Atter thetrain passes by the point X, no simplex current of any character can be detected, and therefore the low cam starting magnet-CSL is also deenergized. This condition of the apparatus causes the low cam to be gradually turned to restrict the speed of the train as indicated in the second droop of the solid line (Fig. 1). It the engineer does not allow the speed of the train to exceed at any point. these permissive speed limits, no automatic brake application takes eil ect.

Cautioncomiitioa; speed cmcessioe.-The gradually decreasing permissive speed limits, indicated by the curves .43 and the solid lines in Fig. 1,.are produced by movement of the two cams; and since these cams are driven from the car wheels, the curves of pern'iissive speed set up are the same for each block or control point on the railroad, whether on an upgrade or on a down-grade; and these pormi. ive speed curves are the same tor the particular locomotive equipped whet-her running alone or pulling a long or a short train. As previously explained, there sometimes are portions of track where it is not possible ilor all trains to keep below the permiss ve speed limits at all points in a caution block, unless the train is handled and braked in some unusual or peculiar manner. I

In conformity with the theory of train control on which this invention is based, it desired. to stin' ulate and enforce vigilance on the part of the engineer in obeying the indications of the block signals, particularly the caution signal. One way of maintaining such vigilance is to penalize the engineer each time he allows his train to exceed the permissive speed limits arbitrarily and automatically established, it being assumed that the engineer, in order to avoid such penalty, will keep vigilant and handle his train safely. Such an expedient for maintaining vigilance is found objectionable in many instances, because it is diflicult for the engineer to observe the arbitrary speed limits for all blocks without special manipulation. Obviously any penalty imposed should be one fair to the engineer and preferably one which the engineer can readily avoid by exercising ordinary prudence and care in the handling of the train.

In view of these considerations, it is proposed in the present invention to provide a penalty which the engineer may avoid in either of two ways, namely, maintaining the speed of histrain at all times below the arbitrary speed limits, or prior to exceeding such abitrary speed limit, manifesting his vigilance by initiating a brake application,

way and so long as alert and vigilant may readily avoid the penalty. In order to be sure that the engineer is alert and vigilant, it is required that he must take the appropriate action before any automatic bra 0 application or other operation occurs, othc wise the engineer might become careless and wait until. he :lclt the brakes being applied. before acting to forestall the penalty.

To facilitate the explanation of these fea tures wherea regular tull service brake application initiated at the block signal or corresponding control point, at which the cam is started, will not maintain the speed ot the train below the pern'iissive speed limits, it the train enters the block at its nori'nal running maximum speed, let us assume a train, running its normal speed of about (59, miles per hour, enters the block I, and suppose for the first set or conditions that the, cngineeris asleep, neglecttul, or otherwise fails to take appropriate action in obedience to the cantion signal. Asthe train continues at the maximum speed limit prescribed by the cam, the speed-distance contacts 6163 open, and decnergizethe electi.'o- )neumatic valve; and since this valve is energized by a stick circuit, once decnergizcd, it remains dcencr ized until picked up by closure of contacts (St-65 at a speed of 2 miles per hour, or substantially stop. In short, it the engineer is negligent, an automatic brake application occurs; and the train nu'lst be brought to a substantial stop before the brakes an be released and the train proceed. This constitutes the penalty for lack of vigilance.

Suppose, however, that the engineer sees and recognizes the caution indieatirm oi the block signal at the entrance to the block I,

and realizing the high speed at which his train is traveling, moves the handle oi? his regular engineers brake valve to the service position for the purpose of applying the brakes, this movement of the bra kc valve occurin before the permissive speed limits are exceeded. So lon as the engii'ieefs brake valve is in the ,1 ice position, it is obvious that the brakes are being applied at the service rate as rapidly as consistent with safety and as rapidly as can be suitably done by any auton atrc brake applying device. In other words, the engineeids manual action tends to slow down the train as efiectively as an automatic ap plication ot'the brakes. The engineer lnrs n'lanijlested in this way his A ance, and the penalty maybe suppressed. It is not necessary in the interests of safety to have the brakes fully applied at the instant the permissive speed limits are exceeded, since these permissive speed limits are se lected and set up on the assumption that the starting of a brake application at that particular point and speed will bring the train to a stop at the desired point. r-Xcco-rdingly, it is suflicient it the engineer gets his brake his brake valve out of the service valve in the service position before exceeding the speed limits, the time taken to get the brakes fully applied being no longer than that required for an automatic application, and due allowance for this time is made in determining the permissive speed limits.

Applying these principles to the specific system shown in Fig. 2, if the engineer is vigilant and puts his brake valve in the service position before the speed contacts 6163 open, the contact fingers 114 are bridged by the segment 67, thereby completing an auxiliary stick circuit for maintaining the valve EPV energized independently of its control. by the speed contacts G2-68, as follows Beginning at .15, contacts 61-114, wires 115 and 112, contacts 7172, wires 113 and 101, winding of the valve EPV, wires 102 and 10?), front contacts 104; of the EPV and wire 105 back to the other terminal C of the battery.

It will be observed that the engineer must move his brake valve to the service position and close contacts 67114 before the valve EPV is operated,otherwise the front contacts 104 of said valve are open and interrupt the auxiliary stick circuit above traced. Hence, the engineer cannot wait until some automatic operation occurs before acting In the ordinary type of air brake system contemplated by this invention, the brake pipe is vented by the action of the equalizing discharge piston valve responsive to pressure in the equalizing reservoir. The engineers brake valve exhausts the pressure from the equalizing reservoir, and the brake pipe pressure .in time assumes a corresponding pres sure, the length of time required to vent the brake pipev varying with. its volume, i. e. length of the train. In the ordinary brake equipment a full service application is made by about 20 pounds reduction; and the engineer may reduce the pressure in the equalizing reservoir about 20 pounds by keeping his brake valve in, the service. position for 6 or 7 seconds. It is unnecessary to exhaust the equalizing reservoir pressure any lower than this, otherwise there is a waste of air in blowing down the brake pipe pressure more than required to give a full service application, It frequently takes a much longer time than 0 or 7 seconds to stop the train; and to avoid this waste of air, the timing mecha-- nism CM is employed; so that if the engineer has kept his brake valve in the service position for 6 or 7 seconds (long enough to make the desired full service reduction in the equalizing reservoir pressure) the timing mechanism will serve to maintain the valve EPV energized and the engineer may then move position to the lap position. i

When the engineer moves his brake valve to the service position to initiate the control of a service brake application, the contact fingers 110 are bridged by the contact segment 69 so as to complete a circuit for the electrically operated valve EV, which is readily traced in the drawings. V'Vith the valve EV energized, the clockwork mechanism CM is started; and. after an interval of 6 or 7 seconds the contacts and 235 are closed, whereupon the device EPV is maintained energized through another partial circuit entirely in dependent of the speed contacts 61 and 63 and the valve contacts 67-114, which may be traced as follows :bcginning at the terminal B, wire 111, contacts 85, wire 112, contacts 7172, wires 113 and 101, winding of the EPV, wires 102-103, front contact 10%, wire 105, back to the common return wire G.

Since the engineer has held the. handle 66 of his brake valve in the service position for this period of time (6 or 7 seconds), the appropriate reduction in the equalizing reservoir pressure for a full service application is assumed, and he may'move his engineers valve into the lap position, the electrically operated *alvc EV being maintained energized through the following stick circuit :beginning at the terminal B, wire 111, contacts 235, wire 11, contacts 68-117, wire 118, front contact 119 of the valve EV, wires 120 and 121, winding of the valve EV, wire 122 back to common return wire C.

If the engineer should attempt to defeat the objects of the invention, and instead of making a full service reduction in equalizing reservoir pressure, should move his brake *alve out of the service position before the expiration of the time interval of 6 or 7 seconds, the valve EPV is deenergized, and thereafter the train must be brought to a substantial stop the bra kes can be released, this assuming of course that the speed of the train at the time in question is above the permissive speed limit. This result follows from the fact that, as soon as the engineer moves his brake 'alve out of the service position, the contacts 67'114 open; and since there has not been time enough for the contacts 85 to close, both auxiliary stick circuits for the valve EPV are interrupted. Also, if the engineer should attempt to release the brakes while the speed is excessive after he has made the recpiircd full service application, the valve EPV is deenergized and the penalty imposed, because in the releasing positions of the brake valve (release or running), thecontacts 6711-t are open, and likewise contacts 69110 are open. The opening of the latter contacts 69 110 dcenergizes the valve EPV and instantly restores the timing mechanism GM to the normal or initial position, opening contacts 85. Both of the auxiliary stickcircuits for the valve EPV are consequently open.

The contact segments 67, 68 and 69, as shown, are of such length that they bridge their corresponding pairs of fingers in the emergency position of the engineers brake (2 miles per hour) before valve as well as in the service position. This is optional but is done'so that, it the engineer makes an emergency application for any reason instead of a service, the penalty will be suppressed just as well as it a service application has been made, it being obviously unfair to penalize the engineer for using an emergency application instead of the service if conditions warrant,

Assume that the engineer has been vigilant and has taken the appropriate actions above described in obedience to the caution signal. As soon as the speed of the train has been re duced to a value less than, the permissive speed set up by the apparatus, the engineer may move his brake valve into the running or release position, releasing the brakes and proceeding at that speed, as shown by the horizontal dot-and-dash line at the point X in Fi 1, the brake control valve EPV being energized directly through the speed contacts 61-63. Since the second low speed cam is initiated at the point X, the engineer is required to again initiate a manual brake application before the permissive speed exceeded, which under the assumed crmdit-ion occurs at the point 26, and he will be required to hold the manual. brake application until the speed of the train has been reduced to less than 20 miles per hour, tor instance, in order to avoid an automatic brake application and the associated penalty, after which the brakes may be released and the train continue to move into the danger block at this limited speed.

Dam e1- coatlition. lien the train enters the block J assumed to be occupied by another train, the loop circuit influence receiving coils 19 will be deprived of trackway energy and the control relay R will assume its deen ergized position regardless of whether or not sin'iplex circuit current is flowing in the block J, because the track or loop circuit 'current is shunted away trom the train in question by reason of the train ahead. Assume now that, with the t "ain in question moving in the block J, the other train heretofore mentioned moves out of the block J into the following block. Under this condition the loop circuit apparatus of the train in question again receives energy from the loop circuit ahead of the train, and the simplex winding of the relay R a current of reversed relative directi on or flow therein, so that the relay R again assu mes the reversed position and permits the Modified for-m of speed c07l-t1' 0Z.-Th'e particular organization of car apparatus shown in Figs. 1 and 2 contemplates two cains governing speeds from a high to a medium, and from a medium to a low speed, respectively. It will be evident that the scheme for imposing vigilance which characterizes this invention is not restricted to this particular torin of speed control. For example, only one cam may be used,- establishing speed limits from an unlimited speed or a maximum down to a low or minimum. In fact, the gradual change in permissive speed limits pro vided by the cam or cams may be eliminated, if desired; and the system operated properly with abrupt changes in speed limit from a maximum to a minimum, or from a maximum to a medium and then to a minimum speed limit.

Double-beadiag.1n hauling heavy trains it is frequently necessary to couple two or more locomotives in the same train. Ordinarily this is done by "double-heading that is, coupling two engines together at the head. of the train. The air brake equipment for locomotives or the usual type is such that, when two locomotives are coupled together in a train, it is necessary for well-known reasons to close avalve between the main engineers brake valve and the brakepipe, commonly called the double-heading cock, on the second or other locomotive in the train in order that the brakes on this helper locomotive may be applied and released fromthe leading locomotive the same as if the helper locon'iotive was a car. in g cock commonly found on all engine equipment, it is possible for the engineer to cutout the automatic brake control, that is, eliminate the functions of i the automatic brake applying mechanism which is set into operation by the deenergization of the valve EPV. This is true whether the v'alve EPV controls an actuator for the regular engineers brake *alve or- "an additional brake applying valve, inasmuch as the connections to the brake pipe should be nia de above the doubleheading cock, otherwise the brakes will be applied on the train automatically I upon exceeding the n'linimum speed limit, because the helper locomotive is unable to pick up track or loop circuit current. In short, by closing the doubleheading cock the engineer may avoid theautomatic application.

Referring to this invention, it Will be evi dent that if the double-heading cock has been closed, the engineer may put his brake valve in the service position for 6 01-7 seconds without applying the brakes in so doing; *et so far as the control or the EPV heretofore described is concerned, such manipulation would. serve to maintain the valve EPV energized and suppress the penalty. As previously explained, however, it is one of the principles or this invention that the engineer On account of this double-headshould not be able to suppress the penalty eXcept by actually applying the brakes; and to assure that the double-heading cock cannot be used, together with the manipulation of the engineers brake valve, to suppress the penalty. the double-heading cock 70 is provided with a contact segment 71 bridging contact lingers 7 2 only if said double-heading cock is open, these contacts being open if the double-heading cock is closed. These contacts 71-72, it will be noted, are included in the auxiliary energizing circuit for the valve FPV. Consequently, if the engineer should close the double-heading cock, these contacts 7172 are opened by this movement, and it is not possible for the engineer to maintain the valve EPV energized and suppress the penalty. 13y reason of this penalty, it is considered that the use of the double-heading cock to forestall automatic brake application will be discouraged, it being much easier to make a brake application in the regular way and forestall the penalty.

Modificdpcn-altg suppressing means (Fig. 3

In Fig. 3 has been shown a portion of the car-carried apparatus of a system, such as shown in Figs. 1 and 2, in which the clockwork mechanism circuit is somewhat simplified by reason of a change in the circuit arrangement resulting from the fact that the device EPV and the valve EV have their windings connected in series at times. In this modified arrangement the electro-pneumatic brake applying device EPV has its winding designed slightly different and is energized by a circuit such. heretofore traced in F ig. 2 which has included therein a resistance 124.

This resistance 124 is substantially the same winding of the valve EV and not the resist ance 124.

In this penalty suppressing arrangement the device EPV is maintained energized independently of its control by the speed control mechanism when the engineers brake valve is in the service position through the following circuit :beginning at the terminal B, wire 125, contacts 126127, wire 128, winding of the-device EV, wire 130, contacts 71 72, wires 113 and 101, winding of the EPV, wires 102, and 103, front contact 104 of the device EPV, wire 105, back to common return wire C. The circuit just traced not only maintains the brake applying device EPV energized but also actuates the electrically operated valve EV thereby causing the contacts 85 to be closed after a predetermined time (0 or 7 seconds) by reason of the clockwork meuimnism CM shows, in. Fig. 2.

Modified penalty suppressing means (Fig. .4).

In the systems thus far described the penalty suppressing means becomes effective as soon as the engineer moves the brake valve to theservice position, and remains effective providing he leaves it there for at least 6 or 7 seconds. In certain railway systems it is deemed practical to require the engineer to maintain the engineers brake valve in the service position as long as the speed of the train is excessive; and in Fig. 4 has been illustrated a penalty suppressing relay PR which makes it possible for the engineer to suppress or avoid the penalty providing he moves his brake valve to the service position before an automatic brake application is initiated and keeps it there.

In the system shown in Fig. 4 (portions thereof being omitted) the devices used are the same those shown in Fig. 2, except that there has been added an additional contact 138 to the brake applying device EPV, and speed contacts, comprising contact fingers 139, which are closed when the speed of the train isless than 22 miles per hour.

Assume that the permissive speed is gradually decreasing and the speed of the train is such that it is just about to exceed the permissive speed limit. If now the engineer moves his valve to the service or emergency posit-ion before the device EPV is deenergized, a pick-up circuit for the penalty suppressing relay PR is completed which may be traced as follows :beginning at the terminal B of a battery. wire 137, front contact 138 of the device EPV, wires 140 and 141, winding of the penalty suppressing relav PR, wire 142, contacts 126127, wire,

143, back to the common return wire C. lVith this circuit completed the relay PR picks up and completes a stick circuit through its front contact 144 which may be traced as follows :beginning at the terminal B, wire 145. front contact 144, wires 146 and 141, winding of the relay PR, wire 142, c011- t'acts 126127, wire 143, back to the common return wire C.

It now the speed of the train exceeds the permissive speed set up by the cam 39, an automatic brake application will be initiated by the device This application may iii however be ineltectual since the auxiliary reservoir has already been partially vented by manual movement of the brake valve to the service position; Even though the device EPV has assumed its deenergized position and has opened contacts 138, the penalty suppressing relay PR is nevertheless maintained energizedthrough its stick circuit including contact 144;, so long as the engineers valve is kept in the service position. As soon as the train speed has been reduced to 22 miles per hour, contacts 139 are closed and the device EPV is picked up through the itollowing circuit :-beginning at. the terminal B, wire 100, contacts Gland '3, wire 101, winding of the device EPV, wires 102-l06 and 1&7, contacts 139, wire 148, contact 149, wire 150, back to common return wire C. After the device EIV is once picked up, it will again be stuck up through its stick circuit including contact 10 so long as the permissive speed setup by the cam is not ex ceded.

lad the engineer put his brake valve in the serviceposition after the brake applying device EPV was deenergizcd in response to excessive spce .l,'the penalty suppressing relay PR could not have been picked up, because the pick-up circuit including the. contacts 138 was not intact, and consequently a penalty would have been inflicted requiring the engineer 'to reduce the speed to less than 2 miles per hour before the device EPV could have again been picked up. Reducing the speed to 2 miles per hour causes closing of contacts (k and 65 and ener'giZation of this device EPV. In otl'i'er words, in the arrange- 1ncnt shown in Fig. 4 the engineer, it alert,

may anticipate the automatic actlon by a.

partial or co'mplete manual brake application, and by so doing is permitted to release the brakes as soon as the speed is less than 22 miles per hour; whereas it he fails to anticipate the ai'ito'n'i'atic action he is penalized by being required to bring the train to a low speed of, say, 2 miles per hour which practically corresponds to a stop.

In the arrangement of Fig. at, whenever the train exceeds the perm'issivespeed limits, the'engineer must keep his brake Valve in the service position until the train has been brought down to a low s1i eed,'assumed to be .22 miles per hour, Keeping the brake "valve in the service position for a11'el.\'ten'ded period of time may result in an unnecessary reduction in brake pipe pressure; but in some cases and under some circumstances, this may not be objectionable, the train 1 158- 'que'i'itl' being braked down to a speed less than a suitable control speedpsuch as 22 miles per hour, be'tore the brake pipe has been materially over reduced.

[Manama systems; ,descv'dptz'oa f Fig. particular Track/wag apparatus.The

type of intermittent system to which the penalty suppressing means embi'idying the present invention has been shown applied is one of the time-distance interval type. This system includes track elements for transmit. ting control influences to the car-carried apparatus of which a pair ol such elements is used to transmit two successive impulses in less than a certain time if the speed of the train is excessive as determined by the spacing of such pair of elements. In order to simplify the disclosure of the system shown in Fig. 5 only one pair of a series of pairs of track elements has been illustrated, this pair being shown at the exit end of the block M, one element of which is controlled by the track relay l of the block N next in advance, the

other element of this pair being permanently.

active.

The first element of each pair comprises a U-shaped core 152 tern'iinating in enlarged pole pieces 153 preferably constructed ot a high grade of laminated magnetic material. The second'el'ement of each pair comprises a similar core having a winding l thereon which is normally closed in a circuit of low resistance by the tront contact 155 of a line relay 156 which is energized when the block next in advance is unoccupied.

Oar-carried rcZays.The car-carried ap pa'ratu's shown in Fig. 5 includes a group oil sensitive and quick acting relays CR, RR and BB. These relays are of the tractive ar 'n'ature type and include wellbalanced light armatures pivotally supported about a vertical axis so as to make them immune to jars and vibrations and causes them to respondto small momentary changes in the flow of current therethrough. Since these relays may take any one of various forms as long as they are quick acting and innnune to vibrations they have been shown conventionally, and are provided with contacts con structed and insulated so as to serve; the purpose for which they are intended and as more clearly described in the operation of the system.

Time elem-eat (Zeo'z'0e.In order to apply the brakes of the train by the deenergization of the electro-p'neumatic valve EPV when two successivecontrol influences are received in less than a certain time, a suitable time element device is required. In the particular embodiment oi the invention illustrated this time element device TE has been shown diagrammatically. This time element de vice essentially comprises a balance wheel 15S which is nominally held in the position shown in the drawings by the time starting magnet TM in opposition to the bias of a spring 159 having its one end "fastened to the shaft 160 and the other end to a pinion 161. This time element device TE is so constructed "that if the timing magnet TM is momentarily deenergized the balance wheel 158 will move in a counter-clockwise direction through an angle of substantially 240 as shown by the dotted position of the contacts 162 and 168. If the timing magnet TM was deenergized for some time, the balance wheel 158 would finally assume an intermediate position substantially 120 toward the left of the normal position. In order to restore the time element device to its normal position when it assumes such an intermediate position, a suitable pneumatically operated restoring device has been provided.

Time element restoring cZe ve'ee.T'his restoring device comprises a rack 165 in engagement with a pinion 161 and adapted to be operated by a piston 166 contained in a cylinder 167 and urged to the extreme right hand position by a compression coil spring 168. An electrically operated device ED, which is constructed substantially identically to that of the device EV of Fig. 2, is provided to restore the time element device TE and certain other devices to their normal position or condition as more clearly pointed out hereinafter.

Speed responsive (Zem'0e.ln connection with the train control system as shown in Fig. a speed responsive device which in dicates the actual running speed of the train at any time is required. In order to simplify the description of the system, a speed governor G of the same centrifugal type shown in Fig. 2 has been illustrated. This device governs the position of a multiple contact speed arm 169 which is adapted to close various circuits under various existing speed conditions, as more specifically pointed out hereinafter.

L /stem wider nownal e0nttizfiona-Under 4 normal clear traflic conditions of the carcarried apparatus, the control relay CR is energized by a circuit which may be traced as follows Beginning at the terminal B of 175, back to common return wire G. This car element L comprises a U-shaped core of magnetic material similar to that of the track elements heretofore described, but arranged in inverted relation and adapted to cooperate with such track elements. lVith the control relay CR energized, the repeater relay R1 and the brake control. relay BR are maintained energized through. the following two circuits (1) beginning at the terminal B, wire 170, front contact 171, wires 176 and 177, lower winding of the repeater relay RR, wires 178 and 179, front contact 180, wire 181, back to common return wire C; and beginning at the terminal B, wire 170, front contact 171, wires 176 and 182, upper winding of the brake control relay BR, wire 188, back to the common return wire C.

lVith the repeater relay Bit and the brake control relay BR energized, a circuit for energizing the timing magnet TM may be traced as follows 2- beginning at the terminal B, wire 18-1, front contacts 185 of the brake control relay BR, wires 186 and 187, winding of the timing magnet TM, wire 188, front contact 189 of the repeater relay RR, wire 181, back to common return wire C.

With the brake control relay BR energized and the time element device energized and in its normal position as shown, a stick cir cuit for this brake control relay through its lower winding may be traced as follows beginning at the terminal B, wire 18 1, front contacts 185 of the brake control relay BR, wires 186 and 192, contacts 162 of the time element device, wires 193 and 194:, lower winding of the brake control relay BR, wire 195, back to the common return wire C.

With the brake control relay BB. in its energized position, a circuit for energizing the primary coil P of the car element L and the c.cctro-pneumatic brake control device EPV in series may be traced follows beginning at the terminal B of a suitable source of energy, wire 196, front contact 197 of the brake control relay BR, wire 198, resistance 199 (used for reasons hereinafter described), wires 200 and 201, primary coil 1, wire 202, contact 203 operated by the rack 165, wire 20 1, winding of the device EPV, wires 205 and 206, front contact 228 of the EPV, wire 229, back to common return wire G.

lVith the primary coil P of the ear element L energized by the circuit just traced, a certain magnetomotive-force is set up in the core of the care-lenient L which causes a certain. amount of flux to pass through the primary coil P. This flux, it is believed, passes to a large extent through leakage paths which do not include the secondary coil 0',

so that, if this car clement bridged by an active track element, the distribution of flux emanating from the leg containing the primary coil P is changed to produce a change of flux in the secondary coil S.

Operation.

relay 156 and putting the core 15% of the secondtrack element of the pair in an open circuit. As the train moves through the block 'N and reaches the first track element of the pair illustrated, the passage of this car element L over this track element causes a sudden increase of flux through the secondary coil S and then a sudden decrease of flux, whereby an alternating wave of elec tro-motive-t'orce generated in the secondary coil corresponding to that of a single cycle of alternating current. l he secondary coil S is preterably connected .in the circuit ot' the control relay OR in a manner so that the first wave of voltage induced therein opposes'that of the voltage of the battery energizing the control relay CR, so that the control relay (JR is momentarily deencr gizcd. This cycle of alternating current voltage induced in the secondary coil S is, it is believed, due to a large extent to diversion of flux from leakage paths through the secondary coil. S and to a certain extent to an increase in the total tlux passing through the primary coil P. The momentary deenergization of the control relay CR permanently deenergizes this relay because its stick circuit including the front contact 1'71 is ln'oken.

With the control relay CR dcenergized, the repeater relay RR is deene'rgized, and since this repeater relay ER is also connected in a stick circuit including its own contact 180, it is permanently deenergized until restored by some other means. lVit-h the repeater relay RR deenergized, the circuit for energizing the timing magnet TM is broken and the time element device TE starts on its cycle of operation. Before, however, the time element device TE has operated far enough to open its contacts 162, the back contacts 207 of the repeater relay RR closes a pick-up circuit for again picking up the control relay CR which may be traced as follows: beginning at the terminal B, wire 18 1, contacts 185 of the relay BR, wires 186 and 192, contacts 162 ot the time element device, wires 193 and 208, backcontacts 207 oi the repeater relay RR, wires 209, 210 and 173, winding of the control relay CR, wire 174-, secondary coil S, wire 175, back to the common return wire C. After the control relay CR has been picked up in this manner it is again in condition jto maintain. the brake control relay BR energized through the circuit heretofore traced, this brake control relay BE in the meantime having been held up by the circuit including the contact 162 of the time element device.

It shouldbe remembered that at the pa rticular stage in the cycle of operation just described the control relay GR is again picked up but the repeater relay is still in its deenergized position, the brake control relay BR being now held up by the control relay CR alone and not also by the circuit including contact 162 of the time element device. When the time element device swings in a countencloclc wise direction, the contact 163 of this device during the last portion of its stroke contacts with the stationary contact 5211 and completes a pick up circuit for the repeater relay RE which may be traced as follows beginning at the terminal B, wire 170, front contact 171 of the control relay CR, wires 176 and 177, lower winding of the relay RR, wires 178 and 219., contacts 211-163, wire 213. back to the common return wire G. Since, as has been assumed, the speed of the train not excessive, the time element device TE will. complete its cycle and return to its normal condition before the car passes by the second track element of the pair; this time element device being held in its normal position by the timing magnet TM, this magnet being energized because the repeater relay RE- is in its picked up position.

Assume that the train now passes over the second element of the pair of track elements, the time element device again starts from its inactive position and completes a cycle of operation in the same manner as just eX- plaincd without imposing a brake application.

Caution. condition (speed excessive, enginccr n01 alert) .Let us assume that the train in ques ion passes by the first element of the pair of track elements in the block M, when the next block in advance is occupied by an other train, and that the speed of the train is excessive. The passage of the train by this first element initiates the time element device TE for reasons heretofore given, so that this time element device has only partly completed its cycle of operation when the car element L passes over the second track element, which now has its coil open-circuited. As the car element passes over the second trackelement, the control relay GR is deenergized as here to'l'ore described. Since the time element device TE has already started on its cycle of operation, the contact 162 is open and theretore deenergization of the control relay CR- deenergizes the brake control relay BR, so that the trout contacts 185 of this relay BR open and thereby prevent the time starting magnet TM from again being energized and the control relay CR from again being picked up. The deenergization'otthe brake control relay BR also interrupts the stick circuit for the brake applying device EPV as heretofore traced, thereby causing an automatic application of the brakes and the stopping of the train, the engineer being unable to restore the device EPV until a penalty has been inflicted which, in the present system, consists in requiring him to reduce the speed to less than. 2 miles per hour.

The time element device TE and the various relays may be restored by the operation of the time element restoring rack 165, which is operated in respo to theenergization of the electroa'esponstvc device ED, W11

217, winding of the device El), wire 218, back I 151 it and will assume their deenergized poto common return wire C. Energizat-ion of this device ED permits the flow of air pressure into the c linder 67 causim the rack to be operated to the left, thereby returning the balance wheel 158 to its normal position, and completing the two following pick-up circuits :(1) beginning at the terminal B, wire 220, contact 203, wires 221, 210 and 173, winding of the control relay CR, wire 174, secondary coil S, wire 175, back to common return wire C; and (2) wire 220, contact 203 on the rack 165, wire 222, upper winding of the repeater relay RR, wire 223, back to conunon return wire C. With the control relay Cit and the repeater relay l-R energized and the time clement device TE in its normal position, the brake control relay BB is picked up, sothat a pick-up circuit for the brake applying device EVP is completed as soon as the push button 224 is released and. the rack 1G5 and its associated contact 203 has re-' turned to its normal position providing the speed of the train is less than 2 miles per hourgwhich circuitcomprises the normally energized circuit for the device EPV to the winding of this device from whence it comcpriscswires 205 and 225, contact 226 of the in thismanner may release the brakes and again proceed along the track in accordance with tra'tlic conditions ahead. The push button is used to avoid unnecessary operation of the time element restoring device every time the train stops.

Caution condition (speed excessioe, engincer (m ficipaz es automatic application) .In view of the foregoing operations of the system shown in Fig. 5 as described, it is of course:

understood that, if the train moves at a speed to receive two successive controlinfiuences in less than a predetermined tune, the relays CR,

sition and the time element device TE will assume its intermediate position. Let us assume now that the engineer has moved his brake valve handle 66 to the service brake ap-' plying position before he passes a pair of spaced elements at excessive speed and the brake control relay BB- is deenergized. Since, under this condition, the brake control device EPVis still up and its stick contact is still closed, a energizing circuit forthis device EPV and theelectrically operated valve EV'of the clockwork mechanism CM heretofore described in connection with Fig. 2 in series is completed and may be traced as follows beginning at the terminal B, wire 230, contacts 231 wire 23?), winding of the device EV, wires 234 and 201, primary coil P, wire 2 02, contact 203 operated by the rack 165', wire 20%, winding of the device EPV, ircs 205 and 206, front contact 228, wire 229, back to common return wire C. Sutlicient current is caused to flow in the branch including the electrically operated valve EV as distinguished from the branch including the resistance 199 by reason of the relative value of the ohmic resistances of thesetwo branches, and the resistance 199 has been added for the purpose of dividing the current for the primary coil P and the device EPV in series between. these two branches in such a way that the device EV responds when the brake valve is moved to the service position. This circuit maintains the brake ap-. plying device EPV energized and inactive and also starts the clockwork'n'iechanism CM described in connection with Fig. 2 so as to close the contacts and 235 a predetermined period of time after the brake application has been started (assumed to be 6 or 7 seconds); It is thus noted that the engincecr may procoed along the track without getting an automatic brake application even though "the speed restriction set up by the spacing of: track elements along the track has been exceeded, providing he has anticipated such an automatic brake application byplacing his brake valve in the service position and keeps it there long enough to make an effective manual application of the brakes and providing he keeps the brakes applied until the speed of the train has been reduced to 22 miles per hour as indicated by the governor G, If the engineers brake valve has been held in the service position for the predetermined time mentioned, that is, until the contacts 85 are closed, he may move the brake valve to the lap position, whereupon a circuit is closed including the device EVand EPV and the following partial circuit beginning at the terminal B, wire 236, contacts 237-238, wire 239, contacts 85, wires 24:0 and After the speed of the train has been reduced to less than 22 miles per hour, the re lays CR, RR and BB and the time element device TE may be restored to their normal condition by the depression of push button 224 which energizes the restoring electro-responslve device ED through thefollowing circuit beginning at the terminal B, wire 241, 7 contact 2420f the speed governor G, wire 243,

contacts 235, wire 24st, push button 224-, wire 217, winding of the device ED, wire 218, back to the common return wire, C. lVith the restor ng device ED energized, the time element device and other changed parts may be restoredto itsnoimalcondition, so as to allow the train to proceed in accordance with traffic conditions ahead: It should be noted that even though-the automatic brake con trol mechanism has been actuated no penalty (reduction ofspeed to less than 2 miles per hour) has been inflicted, because the engineer has anticipated-the automatic brake applica-- tion by a full service manual brake appliczn tion.

that the train inquestion passes by thepair of track elements ata speed in excess of that permitted by the spacing of these elements -wlicn the block N- is occupied; Under this condition ,the time element device TB is initiated on its cycle oi operation when the train passes by the first elemen t for reasons heretofore given. \Vhen the car element L passes by the second track element, even 'though the time element device has not 'yet returned to its normal condition no automatic brake application takes place. This is because the second element is not capable of'transmittinga control influence when its windingl5 l isclosed'in'a'circuitof low resistance. One theory of reasoning by which this immunity of 're'sponse'of the car element words, the-winding 154 on the track elementv acts, itlis believed, as a bucking coil, thereby preventing a material change of flux through the secondary coil of the car element L even though it is disposed in cooperative relation with a magnetizable core 152 of low reluctance. It is thus noted that only one control influence is transmitted from each pair of track devices under clear traffic conditions of a block so that no'speed restriction is set up by these pairs of elements.

Modified penalty suppressing vnetms.

In Fig; 6 of the drawings has been illustrated a system substantially the same as that shown'in Fig. 5 (certain parts thereof being omitted) vin which, the penalty suppressing means includes a" penalty suppressing relay PR substantially the same as that shown in Figgt'requirmg the engineer to anticipate an automatic brake application and requiringhim to keep his brake valve in the service position until the speed ofthe train has been reduced to, say, 22 miles per hour in order to avoidthe penalty of practically coming to a stop. In the embodiment of the iIlVGlltlQll' shown in Fig; 6, ii? the engineer moves hls brake valve to the service position, a circuit is completed-for picking up the penalty suppressing relay PR which may be traced as follows z-beginning at the terminal B, wire 196, front contact 197 of the brake control relay BR, wires 1.98 and 234:, wire 24G, winding of the relay PR, wire 247, contacts 2 i8-2-i9, wire 250, back to common return wire C.

iVith the relay PR in i ts energize-d position, a stick circuit forthis relay is completed as followsz wire 251, front contact 252 of the penalty suppressing relay PR, wires 253 and 2-l(i, winding of the relay PR, wire 247, contacts 2t8-2 l9, wire 250, back to common return wire G. Also, with this relay energized, another circuit for holdingthe device EPV in its energized position-is con'ipleted which maybe tracedas-follows beginning at the terminalB, wire 251, front contact 252 of the relay PR, wires 253, 234and'201, pri'l'nary coil P, wire 202, contact 203 operated by the rack 165, wi re 204, winding of the EPV, wires 205 and 206, front contact 228 of'the EPV, wire 229, back to the common return wire C.

It is thus noted that the train may proceed along the track without the imposition of anaut'omatic bral-Ie application. even though the speed set up by' the spaced track elements is exceeded under caution. trafiic conditions, providing the engineer has anticipated such an application by initiating a manual appli- "at ion. At'terthe speed of'the train has been reducedto 22 miles per hour under the conditions just mentioned, the time-distance brake applying mechanism maybe restored to its normal condition by the engineers operation of the push button 22st, by reason of which the following circuit is completed beginning at the terminal B, wire 254, front contact 255, of the relay PR, wire 256, contact 242, ot'the governor G, wire 244, push button contact; 224-, wire 2l7, winding of the device ED, wire 218, back to common return wire C. The completion o't this circuit returns the time-distance interval brake ap iilying mechanism to its normal position, thereby permitting the train to proceed in accordance with traffic conditions ahead as soon as the rack returns to its normal position.

lVhile'several specific forms of the invention'have been shown and described, and the invention has been applied to speed.- control systems both the continuous inductive control type and. the intermittent inductive control type based on the time-distance interval principle, in each form the primary purpose is to stimulate and maintain vigilance on the part ofjtheengineer, and requiring him un-- derpenalty of being obliged to stop-in order to proceed, to recognize and observe the inclications of the block signals, particularly the plication is initiated. Various penalty suppressing means have been provided for suppressing the penalty in accordance with various degrees of refinement. The first one of these permits the engineer, after initiating the brake application, to put the engineers brake valve back into the lap position, Whereby excessive venting of the brake pipe is provent-ed. This is desirable, so that a corresponding small. amount of air pressure only need be pumped into the brake pipe when the brakes are again released. In the second mentioned penalty suppressing means the engineer is required to keep his brake valve in the service position permanently until the speed oi the train has been reduced to a sate value, which has been taken at 22 miles per hour.

Having thus shown and described several embodiments of the invention as applied to several diili erent types of train control systems, the specific disclosures made have been shown to illustrate the nature of the invention rather than its scope, and it is desired to be understood that various changes and modifications may be made to adapt the invention to various other types of systems without departing from the spirit of the invention or the idea of means underlying the same.

lVhat I desire to secure by Letters Patent of the United States is 1. In an automatic train control system, the combination of means on the train for applying the brakes in the usual air brake system, means for setting up permissive speed limits for the train, penalty means if efiective requiring the train to be stopped each time the brakes are automatically applied before the brakes can be released, and means including a time element device superimposed upon said usual air brake system for preventing said penalty means from becol'i'iing effective and active if and only it the brake valve is in the service position or has been there at least long enough to cause a predetermined degree of brake application since the last time the train brakes have been released.

2. In an automatic train control system, the combination with the usual air brake system including means for applying the ed to the engineers brake valve and effective 1t and only it the brake valve is in the service position or has been there a period of time equal to or more than that necessary to cause,

a predetermined reduction in the equalizing reservoir pressure of said air brake system and has not thereafter been moved to a brake releasing position.

3. An automatic train control system comprising, an automatic brake applying device superimposed on the usual type of air brake system including the usual charged brake pipe, means for automatically actuating said device if predetermined. speed limits are exceeded, means tor penalizing the engineer it similar speed limits are exceeded, and. means for preventing the infliction of a penalty by said last mentioned means including a time element device operatively connected to the engineers brake valve of said system effective if the engineers brake valve has been in the brake applying position for a period of time corresponding to the time necessary to initiate an adequate brake ap iiliciu'ionand has not been returned to the brake releasing position thereafter.

4. In an automatic train control system, the combination of means for automatically applying the brakes ot the usual. air brake system of a train, and means for preventing such an automatic brake application including a time element device separate and distinct from the air brake system itself but governed by the engineefls brake valve which is effective to prevent such brake application a predetermined time atter said time elen'lent device has been initiated and providing the engineefisbrake valve has not therea'ttcr been moved to the running or release position, and

means for initiating said time elen'ient device effective it and only if the engineers brake valve is in the brake applying position.

5. In an automatic train control system, the combination of means for-automatically applying the brakes ot the train it the speed of the train is excessive, means for penalizing the engineer if the speed of the train is excessive, and means including a time element device in addition to the usual air brake system governed by the engineers brake valve for suppressing operation. of said penalizing means effective if and only it the usual engineers brake valve is in the brake applyin position or has been in such position tor a predetermined time and has thereafter not been moved toward the brake releasing position beyond the lap position.

6. In an automatic train control system of the time-distance interval type, the combinaot' a normally energized and normally inactive brake applying device, a penalty in dieting device, means partly on the trackway and partly on the vehicle for transmitting control influence to the car-carried apparatus and including trackway devices spaced in accord-

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