US1578876A - Train control - Google Patents

Description

March 30 1926. 1,578,876

C. S. BUSHNELL TRAIN CONTROL Filed Oct. 9, 1922 2 Sheets-Shea?v 1 l 22 '26 l 25 E s. [Q m ATTORNEY March 30", 1926. 1,578,876

c. s. BUSHNELL. 1

TRAIN CONTROL Filed Oct. 9, 1922 2 Sheets-Sheet 2 Patented Mar. 30, 1926.

1,578,&75

"UNITED STATES PATENT 'orrica.

CHARLES S. BUSHNELL, OF ROCHESTER, NEW YORK, ASSIGNOB, TO GENERAL RAIL- WAY SIGNAL COMPANY, OF GATES, NEW YORK, A CORPORATION OF NEW YORK.

TRAIN CONTROL.

Application filed October 9, 1922. I Serial No. 598,874.

To all whom it may concern:

Be it known that I, CHARLES S. Busrr NELL, a citizen of the 'United States of America, residing at Rochester, in the connty of Monroe and State of New York, have invented certain new and useful Improvements in Train Controls, of which the following is a specification.

This invention relates to automatic train control systems for railroads.

In safeguarding the movement of railwvay trains, it is desirable to make the a.uto-' matic brake application or other control dependent uponcthe speed of the train, since at a given'pointthe speed of the train usu'- ally determines whether or not the train is being safely or unsafely Controlled. For example, upon approaching another train ahead and passing a restrictive caution signal, the following train should reduce its speed; and while the following train may.

travel safely throughout the length of this caution block, its speed at the various points in this block should be such that it may be brought to a stop by its brakes at the end of the block. Similarly, certain track hazards, such as sharp curves, down grades, yard limits, and the like, demand that the speed of the train should be restricted irrespective B0 of the presence or absence of other trains.

ln'accordance with this invention it is proposed to make the automatic brake application at a given point dependent upon the speed of the train at that point in conform- 'it-y with what may be called the time-distance interval principle, that is, the brakes are applied if the train takes less than a given interval of time, measured by a time interval device on the train, in'travelin the given 40' interval of distance, determined y the-spacing of trackway influence devices: This inventiondeals more particularly with the construction of the time interval device, b

7 means of which relatively short interva s 4 of time such as two seconds, may be accu rately measured off. A further object is to provide a time interval device for systems of the character described which has a minimum number of movm and wearing parts, which has its operation dependent upon fundamental factors of mass and accelera tion, and which is so constructed and controlled as tobe thoroughly reliable in'its operation, the interruption of circuits or failure of an essential part resulting in an operation on the side of safety.

In connection with the application of automatic train control to railway-s, it is considered important to retain as far as possible all of the vigilence and care that engineers now observe in controlling their trains, in order that the automatic train control system may afford protection. supplementary to that already existing in the ordinary o eration of railroads, instead of being a su stitute, with the result that before an accident can result not only must the engineer fail to exercise his ordinary care, but also the train control equipment must fail to function.

movement afforded by the vigilance and care of the engineer, it is believed necessary to make provisions to encourage and substantially enforce such vigilance, when an automatic train control equipment is added to the train, otherwise the engineer will be. naturally inclined to rely upon the train control system and allow it to do his work for him. Following out this theory, it is proposed in accordance with this invention to rovide' a manually operable acknowledging device which the engineer must opcrate at each trackway control point under unsafe tralfic conditions, 'in order to avoidan immediate brake application, failure on the part of the engineer to make proper and timely operation of the acknowledging device resulting in the imposition of a penalty, such as, maklng it necessary for the engineer to stop the train and restore the apparatus from the ground in order to proceed. According to this invention, this acknowledging device is incorporated in the system of speed control above mentioned in such a manner that the engineer, by manipulation of the acknowledging device, can not prevent an automatic brake application due to excessive speed.

' The, primary objects of this invention may'be said to consist in the provision of simple, efiicient and reliable mechanism and electrical circuits performin the functions and resultsabove describe t other with other functions essential or desira la in a speed control system of this character.

Various detail purposes, objects and characteristic features of the invention will appear hereinafter-as the description progresses.

In describing the invention in detail, reference will be made to the accompanying drawings in which the apparatus for carryequipped with trackway apparatus adapted to cooperate with suitable car-carried equipment to enforce gradually decreasing speed limits of such car when moving in the direction of the arrow under caution trafiic conditions: r

Fig. 2 illustrates diagrammatically and partly in perspective and section car-carried equipment adapted to enforce decreasing speed limits when used in connection with the trackway system shown in Fig. 1;

Fig. 3 shows a part of the balance wheel and holding or starting magnet of the time control device, and is taken on the line 3-3 of Fig. 2, as viewed in the direction of the arrow; and

Fig. 4 shows the trackway and car-carried equipment of a train control system including an acknowledging device for enforcing recognition of a caution and danger signal, and speed control means for enforcing obedience to a caution signal.

In describing the invention in detail, the

system shown in Figs. 1 and 2 will first be described, this system not being provided with an acknowledging device, that is, a device requiring the engineer to perform a certain act in recognition of a caution or danger signal in order to prevent an automatic brake application, as does the system described in Fig. 4} The system shown in -Figs. 1 and 2 merely enforces speed reduction in obedience to a caution signal, that is compels the engineer to make apredetermined reduction in speed in order to avoid an automatic application of the brakes.

In the embodiments of the invention illustrated, the transmission of the desired.

of two other blocks H and J being shown. The parts and circuits associated with the various blocks are the same, and for convenience will be given like reference char.

acters with distinctive exponents. Each of the blocks is provided with a track'battery 3 and a track relay 4, the same as in ordinary block signal systems. The invention is preferably used with'the usual fixed signals; but these are well known, and I have illustrated such fixed signals Z conventionally, without attempting to illustrate their well known control circuits and devices.

In each block are provided pairs of track elements T and t at the several points in the block at which the speed of the train is to be checked, the spacing between the elements T and t of each pair determining the distance a train is permitted to run in a predetermined time at this point in the controlled trackway elements T and-t is located a repeater track or line relay 8,

these relays 8 being connected in multiple between the line wire 9 and a common return wlre C (not shown), and are energized when the track relay 4 of the block in advance is energized. Since the pairs of track elements at successive points .in the block are substantially the same, except for the spacing between these elements, they will be given the same reference-characters with distinctive alphabetical exponents.

- The energizing circuit for the repeater track relays 8 may be traced as follows starting from the terminal B of a suitable source of energy, wire 10, front contact 11 of the track relay 4, line wire 9,

wire'12, winding of the repeater track relay 8, wire 13 back to the common return .WilB C which is connected to the other side of the source of energy. Fromxthis it is readily apparent that, when the track relay of the block in advance is energized, all of the repeater track relays 8 will likewisebe energized, thus closing their front contacts .14 and including the coils 7 on the back yokes of the track elements t in closed circuits of preferably low resistance.

The car-carried apparatus of one specific embodiment of the present invention has been illustrated in Fig. 2. and comprises suitable devices which will first be separately described. 7 One of these devices coinprises a car element L adapted to be inductively influenced by the track elements T and t along the trackway. This car element L consists of a U-shaped core 15, preferably constructed of agood grade of laminated transformer iron, which terminates in enlarged pole pieces 16, and which is provided with a primary coil- P on one leg,

purpose for which it is intended. Although these relays have been illustrated in the same manner, this illustration is merely conventional and in practice the control relay GR is constructed with much smaller moving parts and controls smaller contacts than do the relays RR and SR, and will therefore function on a' smaller change of current... These relays have their moving parts well balanced sothat they will not be affected by jars and vibration, and are preferably 'I'nountedin a comparatively heavy spring supported relay casing, which may be provided with a glass panel and locked or sealed in any suitable manner. I

The car apparatus. iiiciudes a train control device K which may control the train in any.

suitable manner. This device K has been illustrated as an electric-pneumatic valve, and is intended to cause an automatic application of the brakes, for instance, by venting the brake pipe to make a predetermined reduction only, and simultaneously with such venting cut off main reservoir pressure from the engineers brake. valve'so that the engineer'can not prevent the applicationcf the brakes by operating this brake valve to the release position. The particular construction of this train control device K does not come within thescope of the present invention and has notbeen illustrated in detail.

Another element of the car-carried ap paratus embodying the present invention comprises atime control device TC. This time control-device employs the fundamental factors of mass and-accelerating force to measure time, similar to {the well-known bal-- ance wheel .used in watches- This time control device TC acts .to interrupt and. complete certain circuits after a fixed predetermined interval o'f-"time'after this device has been initiated. W

1 More specificallygithis time'control device H3. comprisesla e plate 20 preferably supported in'a itar ger casing (not shown) in a direction away from these contacts 33 shaft 24 is splined a balance or inertia wheel clearly shown in Fig. 3 of the drawings.

somewhere on the tender, or at any other suitable place on the locomotive or tender, or on an electrically propelled vehicle. On top of the base plate 20 is screw fastened a casing 21 of a general inverted bowl shape, this casing. 21 being provided with an opening and a flange 22 extending around this opening to form a ball race for a thrust ball bearing. To the top of the casing 21 is fastened an upstanding member 23 many 7 suitable manner as by bolts, said member having a forwardly extending portion provided with an opening to serve as a bearing which is in alignment with the flange Pivotally supported in the bearing provided in this upstanding member 23 is a shaft 24 provided with a flanged collar 25 resting on balls 26 to form a thrust ball bearing. I

To the lower end of the shaft 24 is fastened a crank 27 by a pin 28. To the top end of the shaft24 is fastened an enlarged portion 29 by a pin 30. This enlarged por- 1 tion is provided with a saw slotin which is fastened the spring switch member 31 by pins 32. Under normal conditions, this switch member is distorted by bearing against stationary contacts which have been conventionally illustrated by the arrows33 and 34, this switch member 31 being biased and 34 by the spiral spring 35 fastened to the shaft 24by the headed pin 36, and having itsother end fastened by a pin 37 to a sup- 2 port extending from the casing 21. To the hm 40 by the key 41. This balancewheel 40 is preferably constructed of non-magnetic material, 'and has screw fastened to the periphery thereof an armature 42 ofgeneral U- shape having its ends tapered as more clear- 1y shown in Fig. 3. The balance wheel 40 is preferably perfectly balanced in any wellknown manner after the armature '42 has been fastened thereto. y

Supported from the casing 21 by any suitable means (not shown) is an electro-magnet, which will for convenience be called a time starting magnet and designated ,SC, and comprises a back yoke 45 having extending legs 46 terminating in enlarged pole pieces 47 constructed of agood grade of'magnetic material. The pole pieces .47 are pointed-on oneend and provided with an outwardly extending heel at the other end, as more The legs 46 of the electro-magnet are each provided with acoil 48.-"-Tl1is holding or starting magnet ,jSC is normally energized to hold the armature 42against the heels of switch blade 31, to start the balance wheel 40 in rotation. The inertia of the balance wheel 40 will carry the spring switch blade 31 beyond the position to which it is biased and to the dotted position, where it will engage stationary contacts conventionally illustrated by arrows 50 and 51. The Spiral spring 35 will at this time be tensioned in the opposite direction, thereby swinging the balance wheel 40 back to Within a small distance of its original position against the heels of the pole pieces 47. If the starting electro-magnet SC is again energized at the time the wheel 40 returns nearly to its former initial position, said electro-magnet will attract the armature 42, by flux emanating from the pointed extensions of the pole pieces :Ttoward the pointed extensions of the armature to its original position, as illustrated in Figs. 2 and Another element or device of the car-car ried apparatus of this invention comprises a reset device. The primary function of this reset device is to restore the part of the car equipment changed from normal as a result ofa brake application due to excessive speed. In the particular arrangement shown, this resetting, device comprises a shaft 52 suitably journaled in the base plate. 20 and provided with an extending arm 53 and a knob fAoutside of the casing for facilitating rotation of said shaft. A switch member55 is fastened to the extension 53 but insulated therefrom by insulation 56. This switch member 55- is arranged to engage stationary insulated contacts, shown conventionally as arrows, in two extreme positions.

This reset device may be called upon to perform two functions, first, closure of said circuits by movement of the switch member 55, and second, rotation of the balance wheel 40 back to its normal or initialcondition.

The first function is accomplished by turn-- ing the knob 54 in the counter-ciockwise direction as viewed from the top, to move the switch blade 55 from the position shown to a diametrically opposite position into engagement with three stationary contacts. A. second function is performed by the engagement of the extending arm 53 with the downward extending pin of the crank 27, the parts beingso proportioned and arranged that movement of the shaft 52 to its other extreme or operated position will carry with it the crank 27 and the balance wheel 40. if these are displaced from the normal position. back to the normal position.

In. order that this reset device may not he carelessly or maliciously fastened or left in its operated position, and thus prevent the proper operation of thesystem, both by interfering with the movement of the baiance "wheel as, and by maintaining certain cir train proceed, the reset device including switch member 55 .must be restored to and left 111 the normal position shown.

Operation of Figs. 1 and 2.-Let usessume that the car-carried apparatus is in its normal condition shown,that is, is on a car moving between control points in a block when the next block in advance thereof is clear. Under these conditions, the control relay CR is energized through a stick circuit which may be traced as follows:beginning at one terminal B- of a suitable source of energy, such as a battery, Wire 60, front contact 61 of the control relay OR, wires 62 and 63, winding of the control relay CR, wire 6%, secondary coil S of the car element L, wire 65 back to the common return wire C which is connected to the other side of said source of energy.

\Vith this control relay GR in its energized. condition, a stick circuit for-the repeater relay ER is completed which may be traced as follows :beginning at the terminal B of a battery, wire 66, front contact 67 of the control relay CR'wires 68 and '69, front contact 70 of the repeater relay RR, wires 71 and 72, winding of the repeater relay RR, wire 73 back tothe common return wire C.

The energization of the control relay CR also energizes a stick circuit for the stop relay SR which may be traced as follows beginning at the terminal B of a battery, wire 60, front contact 61 of the control re lay CR, wires Hand 75, front contactxiti of the stop relay SR, wires 77 and 8, Windthe common return wire C. The stick circuit for the stop relay SR just traced is also adapted to receive current from a source of energy through a circuit which may be traced as follows :beginning at the terminal B of a battery, stationary contact 323, spring switch member 31, stationary contact 34-, wires 80 and through the rest of the stick circuit of the stop relay SR as heretofore traced back to the'conunon return wire C.

l/Vith the repeater relay ltlt in its energized condition, an energizing circuit for the starting magnet SC may be traced as follows :-beginning at the terminal 18 of a battery, wire 81, front contact 82 ofthe repeater reiay RR, wire 83, coils 48 of the starting magnet SiCm'ir 84c back to the common return wire C.

With the stop reiay in its energized 111g of the stop relay SR, Wire 79 back to SR, wire 87, Winding of the train control common return wire C.

device K, wire 88, stationary contact 57, movable contact 55 of the reset device, stationary contact 58, wire 89, primary coil P of the car element L. wire 90 back to the 'The energization of the rimary coil P produces a inagneto-motiveorce in the core of the car element L, which is in the same direction but greatly predominates the magneto-motive-force produced by the secondary coil S which is connected in the energizing circuit of the control relay, CR. This is due to the fact that the current flowing through the control relay GR is very small, that is, this current is just sufficient to maintain the control relay'CR in its energized condition.- The magneto-motive-force produced by the primary and secondary coils, although being in the same direction, produces very little flux linking both of these coils, this being due to the large gap between the pole pieces 16.

With the car-carried apparatus in its normal condition, as just described, let us assumethat the vehicle equipped therewith is entering the block I when the block J is occupied. lVith the block J occupied, the track relay 4 will be shunted by'th'e wheels and axles of the train in block J, therebydropping the front contact 11 and deenergizing the repeater track relays 8 to open-circuit the coils 7 of the track elements i.

As the car element passes over the first track element T, the reluctance through thecore 15 of the car element is'momentarily reduced. This chan e in reluctance causes a sudden increase of flux through the second: ary coil S, and then a decrease to its normal condition, partly due to a diwrsion of flux from leakage paths and partly due to an increase in the total flux through the )rimary coil P. This sudden increase and recreate of flux through the secondary coil S induces a Volta e therein similar to that of a single cycle 0 alternating current E. M. F. The secondary winding S is preferably so connected with respect to the battery that the first wave of the unicycle of E. M. F. opposes that. of the battery, thereby reducing the energizing current flowing in the winding of the control relay CR to an extent to drop its'armature by the action of the spring 91. Since the control relay GR is connected in a stick circuit, it will be permanently de- .;-cnergized until picked up by some other is not interrupted, because this stick circuit is energized through-the circuit heretofore traced through the spring switch blade 31. The deenergization of the control relay CR does, however, interrupt the stick circuit for the repeater relay RR, thereby causing it to drop its armature and deenergize the starting magnet SC. Simultaneously with the deenergization of the starting magnet SC, the repeater relay RR closes a circuit for picking up the control relay CR which may e traced as follows :-beginning at the terminal B of a battery, stationary contact 33, spring switch member 31 (which has not yet broken its contact with the stationary contacts 33 and 34), wires 80 and 93, back contact 94 of the repeater relay RR, wires 95 and 63, winding of the control relay CR, wire 64, secondary coil S of the car ele-- ment L, wire 65 back to the common return wire C, thereby again energizing the control relay CR through its stick circuit heretofore traced.

The deenergization oi the starting mag-- net SC allows the spiral spring 35 to start the balance wheel 40 upon its cycle of operatlon. lit should, however, be noted that the control relay CRbecomes again ener ized,

' 31 in its extreme position, stationary contact 51, wires 97, 98 and 72, winding of the repeaterv nelay RR-, wire 73 back to the common return Wire C, thereby again energiziug the repeater relay RR through its sti'ckcircuit heretofore tracedJ The energization of the repeater relay RR again closes its front contact 82, thereby energizing the starting magnet SC.

As the spiral spring 35 which is now-torsioned in the opposite direction swings the balance wheel 40, in the counter-clockwise direction (as viewed from above) back to: wards'itsnormal position shown, the armature 42 will be swung into the influence of the magnetism of the starting magnet SC, and will again be attracted to its normal position in cont-act with the heels of the pole pieces l7. l

Darin thiscycle of operation'of the time control device TC above described, the stop relay SR will not be deenergized, because the control relay CR will be picked up before the stick circuit of the stop relay SR through the spring switch member 31 is interrupted. Therefore, the train control assumed that the train did not reach the track element t before the time control device had completed its operating cycle.

Let us assume now that the train passes over the track element T, and thereby deenergizes the control relay CR which deenergizes the repeater relay RR, thereby starting the time control device and causing the back contact 94 to again close the pickup circuit for the control relay CR, as here-' tofore explained, without interrupting the stick circuit for the stop relay SR. If now the car element L passes over the second track element It before the operating cycle of thetime control device TC has been completed, the control relay CR will again be deenergized; and since the auxiliary stick circuit for the stop relay SR is not yet again completed by the spring switch member 31, the stop relay SR will be deenergized, thereby dropping its front contact 76 and inter 'rupting its stick circuit permanently The deenergization of the stop relay SR also causes it to drop its front contact 86, thereby deenergizing the train control device K and the primary coil P of the car element L. The deenergization of the train control device K will apply the brakes in any suitable.

manner as heretofore mentioned, thereby bringing the train to a stop. It is noted here'that the primary coil P is connected in series with the train control device K. This has been done so that the interruption of the circuit through the primary coil P,

due to circuit failure or reduction in cur-.

rent therein below the safe value, will also deenergize the train control device K, there- "by stopping the train.

. 'The train now having been brought to a stop, in order to again proceed, it will be necessary for the engineer to turn the knob 54 of the resetting device. If desired, this time control device TC may be so located on the tender or the like, that it will only be accessible from the ground, thereby requirin the train to be brought to a stop before this resetting device may be operated. If the engineer now operates the resetting de vice by turning the knob 5410 the right and in the counter-clockwise direction (as viewed from above), the contact member 55 will bridge the stationary contacts 100, 101 and 102 respectively, thereby completing pick-up circuits for the repeater relay RR and the stop relay SR.

- The pick-up circuit for the repeater relay R'R-may be traced as follows z-beginning at the terminal B of a battery, wire 105, stationary contact 102, contact member 55, stationary contact 100, wires 106, 98 and 72,

winding of the repeater relay RR, wire 7 3 back to the common return wire C.

The pick-up circuit for the stop relay SR may be traced as follows :beginning a-tithe terminal B of a battery, wire 105, stationary contact 102, contact member 55, stationary contact 101, wires 107 and 78, winding of the stop relay SB, wire 79 back to the com mon return wire C far enough for the switch arm 31to close both sets of its contacts, and also come within the range of influenze of the holding or starting magnet SC, the relays CR- and RR will be automatically re-energized and the balance wheel returned and held in the normal position. Such automatic restoration may not, however, occur under unfavorable conditions; and consequently provision is made whereby manipulation of the reset device may be used to restore the relays CR and RR, as well as relay SR, or the balance wheel, or all.

When the reset device is operated, as just explained, it will be notedthat the spring switch member 31 will come into contact with the stationary contacts 33 and 2-34 before the pick-up circuits for relays RR and SR are completed, thus completing a pickup circuit for the control relay CR through this spring switch blade 31 which has al-v ready beentraced heretofore and includes the back contact 94 of the repeater relay RR. Relay CR, when once picked up, is stuck up through its own stick contact 61. When switch arm55 engages contacts 100-102. The pick-up circuit for relay RR, above traced" is closed, and as soon as relay RR is picked up it is stuck through its front contact '70 and front contact 67 of relay (11. With relay RR energized, its contact 82 is closed 'to. energize the holding magnet SC to hold the balance wheel. If the balance wheel does'not return toward its normal po- (in which it is shown) to complete a circuit Lil between stationary contacts 57 and 58 for this train control device.

Let us assume now that a train equipped with the apparatus illustrated in Fig. 2, and with this apparatus in its normal condi- 'tion as shown, is passing through the block ment L passes over the track element T during the movement of the train, as just explained, the time control device TC and its I coacting apparatus will perform the same cycle of operation as heretofore explained. As the car element L asses over the track element t, no effect will be produced on the car apparatus regardless of whether the speed is hi h or low because the control relay CR wil not be actuated by this track element. Although a very slight change. of flux will take place through the secondary coil S as the car element passes over the track element t with its coil closed in a circuit of'low resistance, this slight change of flux will induce insufficient voltage to actuate the control relay CR, by bucking the voltage of the battery energizing this relay, and therefore will not actuate the same. This slight change of flux is accounted for by the fact that the initial change of flux through the track element causes a relatively large current to set up in the coil 7. i This current, by well-known laws of elec fro-magnetic induction, will be in a direction tooppose the flux producing it. Since only a slight'change of flux takes place through the secondary coil S under these conditions, the control relay CR will be .maintained energized, and the car-carried devices will not be influenced when passing over -a track element having its coil closed in a circuit of low resistance.

From the foregoing it will be seen that i the brakes of a car may be automatically applied at a selected control point along the track in the event that the car is then exceeding some arbitrary speed limit corresponding to the spacing of the track elements at that control point. Obviously, the spacing of the track elements at successive control points may be decreased, thereby allowing the train to travel a shorter distance at each successive point in a predetermined interval of time, and in this manner bring the train to a low speed .at the end of the block.

In Fig. 4 has been illustrated a train control system which in many respects employs the same apparatus as does the. system shown in Figs. 1 and 2, but this system is of more fied contacts.

way is provided with trackwayelements to enforce both recognition and obedience to such a caution signal.

The traekway equipment shown in Fig. 4 is in certain'respects the same as that shown in Fig. 1, and therefore like parts have been given the same reference characters. One outstanding distinctive feature of this trackway system consists of an additional track element which is constructed substantially the same as the other track elements for the purpose of enforcing recognition or acknowledgment of a caution or danger signal, and will for convenience be designated TA. This acknowledging track element TA is provided with a coil 7', which is normallv closed in a circuit of low resistance by the front contact of a distant relay D. This distant relay D'is energized from the line wire 9 and through a front contact 110 of the track relay 4. In this embodiment of the invention, the first track element T of each pair is provided with a coil 111 which is controlled by a front contact 112 of the repeater track relay 8. Although only one pair of track elements have been illustrated, it is proposed that a plurality of control points will be employed for enforcing successive decreasing speed limits substantially as shown in Fig.

The car-carried apparatus illustrated in Fig. 4 employs substantially the same devices as shown in Fig. 2, and-consequently like parts have been given the .same reference characters. The relays CR, RR and SR are the same but are provided with modi- The relays CR. RR and SR are provided with tension coil springs 130.

131 and 132 respectively for operating the movable contacts to their open position when these relays are deenergized.

The time control device TC, which has been conventionally shown, is substantially the same as the time control device shown in Fig. 2, the only distinction being that the nal, that is, in order for him to give evidence that he has recognized this signal and realizes that it is not a clear signal. This device, for convenience called an acknowledging device and designated AD, comprises an operating rod 116 slidably' supported in supports 117 and 118. The operating rod 116 is provided with a knob 119, and has a compression coil spring 120 inserted between this knob and the support 117. The operating rod 116 is provided with an insulating pin 121 adapted to close the movable contact 122 when the knob 119 is depressed, and is provided with another insulating pin 123 which is adapted to allow the spring 124 to pull the movable contact 125 downward against the opposition of the dashpot 126 when the knob 119 is depressed. The movable contact 125 is resilient and does not break connection with the stationary contact 127 until the hook 128engages the end thereof. lt will thus be noted that when the operating knob 119 is depressed the movable contact 12:2 will immediately close a circuit,

whereas the movable contact 125 will not interrupt a circuit until after a predetermined i' .terral of time depending on the retarding ability of the dash-pot- 126. Although any other type of retarding device, or time element device may be employed for postponmg the time of opening of the circuit, the dash-pot 126 has been shown to conventionally illustrate such a time element device.

Operation of Fig. 4.-With a car equipped with the car apparatus illustrated in Fig. d, and moving along the track under clear traflic conditions, the apparatus will be in the normal condition as illustrated. llnder this condition, the control relay CR Wlll be energized through a stick circuit including its own front contact, which may be traced as tollows:--beginning at the terminal B of a suitable source of energy, such as a battery, wire 133, front contact 134i of the control relay CR, wires 135 and 136, winding ofthe control relay CR, wire 137, secondary coil 5 of the car element L. wire 138 back to the common return wire 0 connected to the other terminal of said source of energy.

The energization of the control relay CR closes a circuit for energizing the repeater relay RR, which be traced as follows beginning at the terminal B of a battery. wire 133, front contact 13% oil? the control relay CR, wire 139, winding or" the repeater relay RR, wire 140- back to the common return wire C.

With the repeater relay RR in its energized position, a circuit will be closed for energizing the starting magnet SC, which may be traced as followskfbeginning at the terminal B of a battery. wire 1 11. winding of the starting magnet SC, wire 142. front contact 143 of the repeater relay; RR. wire v 144 back to the common return wire C.

With the repeater relay HR in its energized osition, a stick circuit for the stop relay SR will also be completed. This stick circuit maybe traced as follows :beginning at the terminal 18 of a battery, wire 145, front contact 146 of the stop relay SR, wires 147 and 148, winding of the stop relay Slit,

teasers SR, wire 151, stationary contact 127 of the 1 acknowledging device All), movable contact 125 of this device, wire 152, contacts 58, and 57 of the release device, wire 153. winding of the train control device K, wire 1.54. primary coil P of the car element L. wire 155 back to the common return wire C.

Assume now that a train equipped with the apparatus illustrated in Fig. l in its nor mal condition is moving in the block H, and is just about to enter the block Twhen either of the blocks T or J is occupied by another train. lit is readily seen from th drawing that the distant relay D will be deenergized it either of the. blocks l or J is occupied. With the distant relay deene'rgizcd, the coil if of the acknowledging track element TA will be. open circuited, thereby making this track element efiective to transmit an influence to the control relay CR.

Assuming that the engineer does not notice that the signal Z at the entrance of the block I is at caution or danger, as the case may be, and passes over the acknowledging track element TA, the passage of the car element L over this track element TA causes the armature of the control relay (lit to drop 51 by the action of, the spring 130, thereby deenergizing the repeater relay RE which in turn deenergizes the stop relay and the starting magnet SG, as is readily apparentfrom the drawing. 11s the time control dev ce TC starts on its cycle of operation, a pick-up circuit for the control relay CR will be completed, which may be traced as follows beginning at the terminal B of a battcry, w re 160, stationary contact 114, contact segment 113 on the balance wheel 10, stationary contact 115, wires 1G1 and 136, winding of the control relay CR, wire 13?, secondary coil S of the car element L, wire 138 back to the common return wire (1 The momentary energization of the control relay GR through this pick-up circuit causes it to close its front contacts, thereby again. completing its stick circuit heretofore traced.

The energization of this control relay CR again energiies the repeaterrelay ldlit which in turn energizes the starting magnet SC, so that as the balance wheel 40 completes its cycle of operation it will again be stopped in its normal position by the action of the starting magnet SC. The energization of the repeater relay Blit will, however, not reenergize the stop relay SR, because the dropping of this stop relay has interrupted its stick up circuit at the contacts 146, and

. connection with Fig. 2.

ea ers therefore this stop relay SR will be permanently dcenergizcd, thereby breaking the energizing circuit for the train control device K, and applying the brakes in substantially the same manner as heretofore explained in This function of the train control device K will bring the train to astop, the engineer being unable to operate the reset device, because this reset device is only accessible from the ground, or is locked in a box, the key of which is held by some other person, such as the conductor of a train.

The train having now been brought to a stop, and proceeding on the assumption that the reset device is only accessible from the ground, the engineer may operate the knob 54 of the resetdevice to close a pick-up circuit for the stop relay SR, which may be traced as follows :beginning at the ter minal B of a battery, wire 162, stationary contact 102, switch member 55, contact 100 of the reset device, wires 163 and 148, winding of the stop relay SR, wires 149 and 150, front contact 143 of the repeater relay RR,

wire 144 back to the common return wire C.-

This pick-up circuit just traced will energize the stop relay SR, whereby its front contact 146 will be closed to complete the stick circuit for this relay, as heretofore traced. The energization of this stop relay SR will. however, not energize the train control device K until the operating knob 54 of the reset device will be returned to its normal position to complete the circuit for the train control device K through contacts 55, 57 and 58. It is thus seen that if the train passes either into a caution or danger block without acknowledgement of the engineer that he has observed he has passed a signal which does not indicate clear. by the operation of the acknowledging device AD, that the brakes of the train will be applied in a manner unpreventable by the engineer, thereby requiring the train to be brought to I a stop after which the train control apparatus may be reset to its normal condition by the engineer from the ground, and in this manner penalizing the engineer for not observing or recognizing such a caution or.

danger signal. i

Let us assume now that the train is entering the block I under either of the same trafli'c conditions (caution or danger) and that the engineer is operating the ackn0wledging device AD at the time that the car element L passes over the acknowledging track element TA. As the car element L passes over the acknowledging track element T A, the control relay CR will be actuated, thereby interrupting its stick circuit and also the energizing circuit for the repeater relay BR. The deenergization of the re peater relay RR deenergizes the starting magnet SC, thereby allowing the time control device TC to start upon its cycle of operation.

It should be noted at this time that the deenergization of the repeater relay RR does not deenergize the stop relay SR, because this stop relayis energized through a circuit which may be traced as follows :--Beginning at the terminal B of a battery, wire 145, front contact 146 of the stop relay SR, wires 147 and 148, winding of the stop relay SR, wires 149 and 165, normally open contact 122 of the acknowledging device AD, wire 166, stationary contact 34, movable spring contact 31, stationary contact 33 of the time control device TC, wire 167 back to the common return wire C. The first increment of movement of the time control device TC completes a pickup circuit for the control relay CR through the contact 113 as heretofore traced, thus causing the control relay CR to complete its own stick circuit and again be permanently energized. The ener-.

'gization of the control relay CR again energizes the repeater relay RR, which in turn again energizes the starting magnet SC, and also completes the main stick circuit for the stop relay SR heretofore traced.

. It should be noted that the control relay CR and repeater'relay RR will again be picked up, as just explained, before the cirlitlll Let us assume now that'the train in question is moving through the block Iwhen the block J is occupied by another train. Under this condition, the track elements T and t will have their coils open-circuited because the track relay 4 will be denergized, thereby deenergizing the repeater track relays 8 which will drop their armatures 14 and 112, thereby opening the circuits through the coil 7 of these track elements.

As the car element L passes over the first track element T, assuming that the engineer is aware that he is in a caution block'and is operating the acknowledging device, the car apparatus will be actuated through the same and cycle of operation as occurred when the train passed over the acknowledging track element TA, as just explained. If now the train has reduced its speed sufliciently so that it will not reach the second track element t until the time control device has completed its cycle, and has again completed the circuit through the spring switch blade 31 and the contact 122 of the acknowledging device AD, this same cycle of operation will be repeated when the train passes the track element t, and the brakes will not be applied providing the engineer has operated the acknowledgingdevice AD.

Let us assume now that the train has passed over the first track element T under caution trailic conditions. The engineer operating his acknowledging device Al), the

time control device will be started on its cycle of operation, thereby picking up the control relay CR which will energize the repeater relay BR, as heretofore explained. Assuming further that at this time the train is exceeding the speed limit enforced by the spacing of the particular track element in question, and that it passes over the second track element t before the time control device has completed that portion of its cycle through which the spring switch member 31 is not in contact with the stationary contacts 33 and 34, the deenergization of the control relay CR at this time, due to the passage of the car element L over the track element t, interrupts the energizing circuit for the repeater relay RR which in turn deenergizes the stop relay SR, because the auxiliary circuit for this stop relay SR through the normally open contact 122 of the acknowledging device AD is now open at the spring switch member 31. The deenergization of the stop relay SR will open the energizing circuit for the train control device K, and apply the brakessubstantially in the same manner as heretofore described, the engineer being required to reset the relay SR and train control device K from the ground before he can again proceed.

It should be noted that if the engineer attempts to defeat the purpose of the acknowledging device AD by tying it down or maintaining the operating knob 119 in its lower position in any other way, that the train control device K will be deenergized after an interval of time depending on the time element device illustrated'as a daslrpot 126. The time element device of the ac.- knowledging device AD may be adjusted to allow sufficient time, so that the engineer need not acknowledge each element but that a. pair of elements may be passed by a single actuation of this device.

It is thus seen that the train control sys tem disclosed in Fig. 4 may be used to en force'recognition of a danger or caution signal by providing an acknowledging track element TA just before the entrance to a block; that this system may be used for enforcing obedience to a caution signal by providing pairs of track elements in a block controlled by-the next block in advance which are spaced to enforce decreasing speed limits at successive points in the block in the direction of trailic to bring the train to a low speed. of, say, ten miles per hour before entering the next or danger block; and that this system may be used by providing both types of. track elements to enforce both obedience and recognition of a caution signal. This latter feature maybe desirable in very long blocks where a caution signal should be acknowledged upon the entrance to the'block, but the speed may not be required to be reduced until the train has passed a considerable distance into. such block. A

The present invention may be readily applied to enforce reduction in speed at the approach to sections along the trackway which are permanently hazardous, such as, approaches to curves, down grades, drawbridges, interlocked territory. and the like. This may be done by providing pairs of permanently active track elements, such as the element '1 shown in Figs. 1 and 2 of the drawings, at suitable points back of such point of hazard. If car apparatus such as shown in Fig. 4 is used, it will be necessary for the engineer to do both, acknowledge the passage of such elements and reduce the speed inaccordance therewith, in order to avoid an automatic brake application.

In order. to give the engineer the proper information in regard to the speed reduction necessary, suitable permanently effective markers may be provided, either in the form of a sign board or an illuminated marker. Similarly, suitable marker lights may be provided at traffic controlled control points to inform the engineer whether he is in a caution or a clear block, what speed limit will be enforced at this control point under caution traffic conditions, or both, such marker lights being preferably controlled by the repeater relay 8 located at the particular control point.

In practicing the invention shown in Fig. a, certain portions of the trackway, for instance, such as a branch road used mostly for freight carrying purposes, may be provided with an acknowledging track element only which may be considered a sufficient: safeguard for this inferior trafl'ic territory; Whereas other portions may be provided with spaced pairs of elements to enforce predetermined permissive speed limits.

lln certain other territory, especially territory employing long blocks, it may be desirable to provide an acknowledging element just before the entrance to a block, and provide speed enforcing pairs of elements at later points in such block to afford the desired safety, thereby giving the full protection afforded by the system shown in Fig. 4 as has already been described in detail.

vcntion, there have been shown and described several typieal embodiments thereof which have been selected more with the view 0t facilitating explanation of the invention, than for the purposes-of disclosing the specific structure and arrangement of parts and circuits preferably employed in practice; and it should be understood that various adaptations, modifications and addi tions may be made to this particular disclosure without departing from the invention. For example, it is contemplated that the system may be used in conjunction with any suitable or well-known type of block signal system, using either direct or alternating current in its track circuits, and that various forms of mechanism for controlling the application of the brakes and the supply of propelling power may be used and governed in the same way as the train control device K, such brake control mechanism being of course designed to effect an automatic brake. application that can not be forestalled or prevented by the engineer, and in a manner conforming with recog nized air-brake practice.

Other deviations from the specific disclosure will be evident to those skilled in the art, and I desire to have it understood that the specific structure shown and described is merely illustrative of the invention, and

does not exhaust the various embodiments thereof.

What I claim is 1. A train control system of the type in which the train will be automatically re-' tarded if it traversesa predetermined distance in less than a predetermined time, in-

' eluding a time controlled device having a cycle of operation the time of which depends on the mass of an oscillatable moving part and the accelerating force of a spring acting to accelerate the mass first in one direction and then in the other. 1

2. Atrain control system of the type inwhich the train will be automatically re-' tarded if it traverses a predetermined distance in lessthan a predetermined time, 1n-

eluding a time controlled device having a cycle of operation requiring saidpredetermined time in which a mass is acted upon by a spring 'so as to be accelerated andthen deeelerated in one direction, and is then accelerated and decelerated back in the other direction toits normal position;

3. A train control system of the type in which the train will be automatically retard'ed tance in'l'essthan a predetermined time, including aetime controlled device having a cycle of operation in which a mass-is accelerated and then decelerated in one direction, and is then accelerated and decelerated back; in the other direction to its normal pesiti'on, and meansfor controlling traverses a predetermined distrolled bysaid time controlled device during each cycle of operation thereof.

4. Car apparatus for train control systems comprising, influence receiving means, a brake control apparatus, a normally energized stick relay for controlling said apparatus, and means for dropping said stick relay when two successive control influences are received in less than a predetermined time, said last mentioned means including a time element device having a cycle of operation dependent on the period of oscillation of a pivotally supported biased weight.

5. Car apparatus for train control systenis comprising, influence receiving means, a brake control apparatus, and means for actuating said brake control apparatus when two successive control influences are received in less than a predetermined time, said means including a time controlled device having a mass held in one position and biased to another position, whereby re leasing of said mass causes it to accelerate,

and then decelerate in one direction and then accelerate and again decelerate in the other direction and return substantially to its normal position after the expiration ofa predetermined period of time.

6.- Car apparatus for train control systems comprising, a control relay connected in a stick circuit, means actuated fromthe trackway for governing said control relay, a time controlled device employing the balance wheel principle for interrupting a circuit.

tuating said brake. control apparatus when two successive control influences are received in less than a predetermined time, said means including a time controlled device having a mass held in one position .and biased to another position, whereby releasing of said mass causes it to accelerate and then decelerate in one direct-ion and then accelerate and again decelerate in the other di rection and return substantially to its nor mal position after the expiration ofa predetermined period of time, and separate means for restoring said device to its normal position in the event it comes to rest in the biased position.

8. A train control system of the type in which the train will -be automatically retarded if it traverses a predetermined distance in less than a predetermined time, including a time controlled device havin a normal biased position, means for, resetting said device back to said normal position when it has changed to its biased position,

means is in its operative position.

9. Car-carried apparatus for train control vsystems, the combination of a brake control apparatus actuated when two successive control influences are received from the trackway in less than a predetermined time measured by a time element device, said time element device comprising a mass having a normal position and held there by a mag netic field, means for biasing said mass to a neutral position, and means for controlling said magnetic field to allow said mass to move beyond its biased neutral position and then back into said magnetic field.

10. Car-carried apparatus for train control systems, the combination'ot a brake control apparatus actuated when two successive control influences are received from the trackway. in less than a predetermined time measured by a time element device, said time element device being of the balance wheel type in which the balance wheel is held in a biased position and is released upon the reception of a control influence and is again held in such biased position after the expiration of a predetermined period of tlme.

11. In a train control system, the combination of a plurality of pairs of track elements which comprise inert magnetic bodies when in their active stopping condition, and devices on the vehicle adapted to receive influence from said track elements, and automatic means including a time element device of the balance wheel type for applying the brakes if two successive influences are received in less than a predetermined time.

12. A speed control system of the character described comprising, in combination with brake control apparatus on the vehicle including a time interval device of the balance wheel type, of means partly on the vehicle and partly on the track and cooperating through an intervening air gap for imposing control influences on said vehicle in succession dependent on the distance of travel of said vehicle.

13. Brake control apparatus for train control systems of the character described comprising, a main control relay and a repeater relay, brake control mechanism and a time controlled device of the balance wheel type, said device cooperating to produce an automatic brake application if two successive operations of the control relay occur in less than a predetermined time.-

14. In anautomatic train control system, the combination of influence transmitting devices along the traekway, influence receiving devices on the vehicle, an acknowledging device, a brake-setting appliance, and means for actuating said brake-setting appliance to its active condition if a single active influence transmitting device is passed over without the actuation of said acknowledging device, or it two successive active influence transmitting devices are passed over in less than a predetermined time regardless of whether said acknowledging device has been operated.

15. An automatic train control system of the type in which the train will be automatically stopped it' it traverses a predetermined distance in less than a predetermined time comprising, trackway influence com1nunieating devices located at successive points along the trackway spaced so that the distance between successive elements determines the distance the train may travel in a predetermined period of time, abrake setting device adapted to act on the usual air brake system and apply the brakes if actuated, means for actuating said brake setting device if two successive active track elements are passed over in less than a predetermined time, an acknowledging device, and means for actuating said brake setting device each time an active trackway device is passed by unless said acknowledging device is held in its active position during such passage.

16. In a train control system, the combination of a trackway system comprising territory having traekway equipment for enforcing predetermined restrictions in the speed of a. train under caution trafiic conditions, and territory for enforcing recognition of a signal indicating caution, car-carried equipment including a brake control device and an acknowledging device for applying the brakes if the speed is not restricted or the signal is not acknowledged to manit'est its condition when passing through the re'ipective territories under caution traflie conditions, and means for restricting the movement of the train it said acknowledging device is continuously held in its active con dition.

17. Car carried apparatus for automatic train control systems of the type in which the speed of the train is restricted by permitting it to travel only a predetermined but variable distance in a certain interval of time comprising, an influence receiving means, a brake setting device, a manually operable acknowledging device, and time controlled means for actuating said brake setting device if two successive control influences are received from suitable trackway devices in less than a predetermined period of time, said last mentioned means including means for actuating said brake setting device upon the reception of a single control influence unless said acknowledging device is simultaneously held in its active position.

18. Car carried apparatus for automatic train control systems of the time-distance interval type comprising, a brake settingdevice, a normally energized stick relay formaintaining said brake setting device inactive, a cyclic time controlled device of the balance wheel type adapted to maintain the stick circuit for said stick relay closed so long as this device is in its normal condition and which performs a cycle of operation requiring a predetermined period of time when initiated after which it again reaches its normal inactive position, a normally energized control relay normally maintaining an auxiliary stick circuit for said stick relay closed and maintaining said time controlled device in its normal dormant condition which is momentarily deenergized upon the reception of a control influence from the trackway, whereby the reception of a single control influence causes the time controlled device to perform a cycle of operation during which time it is incapable of maintaining the stick circuit for the stick relay elated during which cycle said stick relay ismaintained energized by said control relay and whereby if two control influences are received in less than a certain period of time the reception of the second control influence causes deenergization of said relay and initiation of said brake setting device.

19. Car carried apparatus for automatic train control systems of the time-distance interval type comprising, a normally energized stick device which if deenergized causes an automatic brake application by acting on the usual air brake system, a

normally energized control relaywhich When.

inits normal condition completes a stick circuit for said stick device and which assumes a deenergized position momentarily upon the reception of a control influence from the trackway, a time controlled device of the balance wheel type normally maintained in its inactive condition by said control relay and which when in said normal condition completes a stick circuit'for said stick device and which if deenergized performs a cycle of operation requiring a definite period of time by reason of the acceleration and deceleration of a mass, whereby the reception of a single control influence initiates said time controlled device upon its cycle of operation and the reception of a second control influence before the time element device returns to normal causes deenergization of said stick device.

20. Car-carried apparatus for train control systems including a cyclic time clement device and suitable control relays therefor, of an electro-responsive device connected in a stick circuit for controlling the brakes of the vehicle, means for interrupting said stick circuit by a single operation of said relays, means tor manually preventing such interruption, and means for interrupting said stick circuit if two successive operations off-said relays occur in less than a predetermined time which interruption can not be prevented by operation of said last mentioned means.

21. Car carried apparatus for automatic train control systems of the type in which the brakes are applied if two succe;sive control influences are received in less than a predetermined period of time comprising, a normally inactive brake setting device superimposed on the usual air brake system which if actuated causes an automatic application of the usual air brakes, a manually operable acknowledging device, and means including a time controlled device for causing actuation of said brake setting device upon the reception of a single control influence from the trackway unless said acknowledging device is held in its active position and for actuating said brake setting device regardless of whether or not said acknowledging device is held in its active position if two successive control influences are received from the trackway in less than a predetermined period of time.

22. Car carried apparatus for automatic train control systems of the time-distance interval type comprising, a normally energized stick control relay adapted to be deenergized upon reception of a momentary control influence transmitted from the trackway, a normally energized repeater stick relay having a stick circuit including a front contact of said control relay and which if deenergized completes a pick up circuit for said control relay, a normally energized stick brake control device having astick circuit including a front contact of said control relay which if deenergized causes an automatic brake application by acting upon the'usual air brake system, a time element device of the balance wheel type which is held in its normal position by a circuit including a front contact of said repeater relay and in this position maintains an auxiliary stick circuit for said brake control device closed and which when initiated upon a cycle oi operation by deenergization of said repeater relay again closes a pick up circuit for said repeater stick relay, whereby the reception of a single control influence from the trackway causes the relays and time element device to perform a cycle oi sequential operations and the reception of two'control influences in less than a pre determined period of time causes deen'ergization of said brake control device because both the stick circuit and the auxiliary stick circuit for said device are simultaneously broken.

23. Car carried apparatus for train controlsystems, the'combination of a brake control apparatus actuated when two suecessive control influences are received from the trackway in less than a predetermined time measured by a time element device, said time element device comprising-a pivotally supported balance wheel biased to a mentary deenergization of said electro 10 certain intermediate position by a spring, an magnet causes said balance Wheel to comelectro-magnet acting on an armature asplete one cycle of oscillation after WhlCh 1t sociated with said balance Wheel normally is again attracted to its normal position by holding said balance Wheel in one extreme said electro-magnet. position against the bias of said spring, and In testimony whereof I hereby aflix my 15 contacts opened and closed in a certain sesignature.

allence by oscillation of said balance Wheel,

e various parts being so designed that 1110- CHARLES S. BUSHNELL.

Images