US1626833A - Train-control system - Google Patents

Description

y A. E. HUDD ET AL TRAIN CONTROL SYSTBI Filed Oct I 29. 1921 5 ShQOtWOQZ 1 A. E. HUDD ET AL TRAIN CONTROL SYSTEI mm on. 39. 1921 5 Sheets-Shoot 3 y A. E; HUDD ETAL TRAIN CONTROL SYSTEI Filed on. 29. 1921 5 Shanta-Shut 4 FIG.7,

May 3, 1927; 1,626,833

' A. E. Hunt; ET AL ruin CONTROL sys'rsu Filed on. g9. 1921 s shuts-sheet 5 I '56 L fi J40 m'f%//z/////////////////////////////////////% 154 Patented May 3, 1927.

Qumran .zSiTAT ES mama-Nit so as-res.

@ALFRED ERNEST HUDD,'0F LIVERPOOL, ARTHUR'FBANK'BOUNI J, OE TIMPERLEY, Y's-ENGLAND, ASSIGNORS, BY- MESNE ASSIGNMENTS, TO AUTOMATIC ELECTRIC-INCL,

on CHICAGO, ILLINOIS.

TRAIN-CONTROD- SYSTEM.

Application fi1ed=0ctober 29, 1921, Serial No. 511,322.,k-ai1'diin Gr'c at Britainfloveinber 18;!3920.

'T he present d1wentionconcernsimprove *ments in or-relat1ng to train control systems. In order that such" systems i should be of generalapplioation, it is important that in addition to being reliableand efiicient, theyishould be simple and avoid-any undue interference with the normal runs 'ning'of the trains, while inaddition, thecost of the apparatus should not be unduly thigh. "It is also important that :the apparatusshotild meet varyingv conditions in idi'ifer ent'ipla'ces and should operateequally effectively at all times.

is to providea ramp or tripping devlceat -is=still at danger when. reached, an emergencytapplication of the brake is applied.

This arrangement fails,=because the engine,

may be'running at too great a speed when avmistake on the part of the driver) to be pulled up in time toavoid an accidental- It is therefore important; that the 10me signal shouldainot be passed at an excesyond the home signal. Preferably two;

brake cont-rolling elements are provided, one as usual at: the' home signal which'wo'uld pull up within the *block'clearance a train travellingat saygBO miles an hour, whereas,

trains exceeding this speed at a point where the fastest train could be pulled up within the blockclearance.

It will thus be seen that the emergency application is only applicable ifa train is at a distance from the' home signal and travelling at such a speed, that unless the brake is immediately applieth'the train will One arrangement npass beyond the regulation' block clearance with the home signal at danger.

: Briefly, the rules governing the invention maybe summarized in the following statement :-The distance run by the fastest 'train beyond thehome signal, assuming that such a train "had-the emergency application of the-brakes applied at a predetermined positi on,-:sh0uld equal the distance run by': -a

"slow train which has its brakes applied at the home signal and which? is running at such a speed as to just permit' 'it passing the predetermined position-without having itsbrake's applied. By this mean's' having 'thewclistant signalso that=if-zth1s signalis at danger,. a service application of the brakeiislappliedywhile if thewhome signal the necessary data for. any particular location, the position-at which the firsti"emer-' gency applicationmay be: applieidgcan be readily obtained.

By varying the point of application ac cording to the speed of the train, a reduction I v -may bmm'ade v in the staridard blockl clear- PELSSlIlg the home slgnal (due to neglector' ance operating on- English railways, so

v whereas, existing known systems would, if though the emergency application is ap lied.

absolute safety is to be secured, necessitate v creased-as trains trave'lling at'1high' s eds sive speed. :Agannan engine'drlver shouldhave complete liberty to speed up his train ,V as soon as the home signal :is lowered, and

on a falling gradient might'travel a dis tance Well over 100%in excess of block clearance when not' tripped till passing the home signal itself. I r

Another feature of the invention consists of atime element device adapted to ("be used for determining the speed of a-train and for'rontrolling' the applie'ationof the brakes if the train passes between two points in lessthan a predetermined time;

According to the invention'the time ele- 1 'ment is adapted to be set'in oper'ation against a continually acting restoring forcenvhen the train passes a certain point. and is subsequentlymaintained in operation while the train asses over a given J track. 'By its operation it causes the brakes to be" applied.

if the train reaches ajgiven point before the other HDPllCfltlOl'l would be applledto a predetermined time, while after the'train has left the track the time element device is adapted to be automatically restored to I i 'normal. Such an arrangement 'is applicablev with. train control systems in which it is required to bring the train to rest within a given block clearance as described above, when in such a case, the application of the brakes would be jointly under the control of the signalling system and the time ele ment device, so that if the signals were clear, the brakes would not be applied the time element device being only operable if the signals are at danger.

In the preferred form of the invention track circuits are provided which are controlled by the train for effecting the application of the brakes if the train should exceed. a predetermined speed. while another feature of the invention is a time element device controlled by periodic moven'ient. By way of example. a preferred form of carrying the invention into ellect will be described although it, will be understood that considerable modifications may be made therein by those versed in the art without departing from the spirit of the invention.

Referring to the drawings, Figure 1 illustrates a diagrammatic lay-out of the apparatus required for one construction of the invention in the vicinity of the home and distant signal. Figure 2 shows diagrammatically the apparatus provided on the train and the circuit connections while Figure 8 is an amplification of Figure 2 giving the mechanical features ingrcater detail; Figur 4 illustrates diagrammatically a modification of the train control system shown in Figure 1 embodying the principles of the present invention. Figures 5, 6, T and 8 illustrate in greater detail the time element device shown diagrammatically in Figure 4.

Referring to Figure 1, the rails of the track are represented by the references 1, 2, while the distant and home signals which are manually controlled are represented by the reference letters I) and H respectively. To the left of the home signal a short length of track constituted by the rails 3 and 4 is isolated from the main track, said isolated section having a battery 5 connected across the rails at one end,and a track relay 6 connected across the rails at the other end. Adjacent the track and in a suitable posi tion to engage with shoes on the passing engine are four ramps 7. S. 9, while T represents a time clement device for the pun pose oi ascertaining the speed of the train between the ramps 8 and 9 i. e. whether the speed exceeds or "falls below a certain speed according to the time taken to pass from ramp 8 to ramp 9.

The same element device T consists of an electromagnet 11 having an armature 12 which is adapted to pull up immediately the electromagnet is excited and close contacts 13 and 14. The attraction of the armature p aces a tension on the open helical spring 15 so that a torce is exerted on the toothed sector 16 pivoted at 17 to cause this to rotate. The toothed sector 16 is geared with a pinion 17 coupled on the same shalt as a spur wheel l8 which gears with a pinion 15) on a shal't carrying a fly or air brake 20; the sector lb can only rotate comparatively slowly and therefore some time will elapse before the contacts 21 and 22 are closed. ll for any reason the electromagnet 11 should become (lo-energized, the armature 12 tends to resume its normal position under its own weight and thereby the sector 16 is permitted to return to normal also under gravity control. It should be mentioned that sccured to the sector 16 is a. leaf spring 23 adapted to engage with the adjustable contarts 24 and 25 The purpose of these adjustable contacts is two-fold. Firstly. they control the initial energizing circuit for the electromagnet l1, and secondly. they adjust the length of travel of the sector 16 so that the time taken for the arm 16 to travel from its normal to its operated position may lIO adjusted within a considerable range to suit various speeds of the train or various lengths of track over which the speed of the train is to be regulated. The contacts 26 and 27 are controlled by the starting and home signal levers respectively, the full lines showing the position of the contacts when the signal levers are in their normal position and the dotted. lines showing the position of the levers when in the ()l'lelzllltitl position. The contacts 28 and 29 are provided in connection with single line working only and are operated to the positions shown in full lines or dotted lines respectively, according as to whether the direction of running is from right to left as illustrated or in the reverse direction. When used for double line working. the terminals 30 and S1, and 32 and 33 are connected together as shown by the lines of (lots. while when used for single line working the connection shown by lines of alternate dots and dashes are used.

.lefore (flescribing the operation or" the system, a description will be given of the apparatus provided on the cno ine. and for this purpose. reference should be made to Figures 2 and The principal apparatus comprises a electromagnet 34 which controls by its arm ature 35 a valve 36 which when open admits air to the vacuum chamber i)? thereby causing a full application of the brakes. In addition an electron'iagnet 38 is provided adapted to control by its armature il the valve 10 which, when open permits a restricted amount of air to pass through the opening 41 and the reed 42 into the vacuum chamber 37. thereby causing partial apoih cation of the brakes and the emission of a warning signal to the driver. other ap paratus comprises a battery l3. A. bell l-l,

lltl

restoring plungers and '46 and a device 47 for resetting the valve 36 011 its'seat; a reversing switch 4-8 adapted to be controlled either by the position of the engine reversing gear or by thc'd'irection oi the rotation of the axles is provided for switching'over the electrical connections totheshoes 49- and 53, 54: and normally engage,'so that these are normally all in contact. When however, the shoes are deflected tothe right or to the-left, one of the brushes in and 55 is isolated in the insulated gap 57 inthe contact plate 56. The reason for this will be underdescribed. Having g,'ene1"ally described the apparatus empl0yed,a description willno'w be given of the operation ofthe system and later on a description will .be given of the operation of certain details of the invention which are important in providing a thoroughly reliable and practical system of train control.

It will be assumedinthefirst case that a train is amaroachingin the direct on shown" by the arrow and that both the distant and home signals are clear. In 'suchcircumhen the engine approaches ramp 7, it will be noted that the shoe 49 i will be deflected towards thetrain sothat a Ca the brush 55 will be isolated. Now, normal ly, the electromagnet 88 is energized in the "following circuit: positive pole of battery ,4l3,-lead 60, contact device61 (which will be described later) brush 5.3,"contactp'late56, brush 55, right hand winding of electromagnet 38 and winding of electromagneh(56 and arn'iature 67 in parallel, contact (32, ari'nature 39, contact 63 to negative pole oi It Will thus be appreciatedthat valve 40 closed. However, when arn 49 is deflected, this normal energizing circuit is broken, butas the ramp 7 connected to battery 58, a circuit may be traced through the shoe 49 and its support 64 through the left hand winding of the electron'iagnet 88 to the, frame of the; engine and thence to the rail .2 to negative'pole of battery 58, the

-electromagnet 38 is therefore maintained energized so'that the armature 39 cannot fall fore without effect.

away and there will "beno partialapplicati'on otthe brakes at this point. "The-"electroinagnet 66 is however tie-energized and 1 at itsarmature '67 closes a *circui.t for the bell itt'whrch maybe traced as l ollowsw- 70 Positive pole-oi b'attery ei-i, bell le't, armature 67 and its 'right-hand contact, contact G2,ar1-'nature 39,contact 63 to negative pole of battery'eli. The bell 44 therefore rings shoe 50 'willbe engaged. Under 'this conand indicatesto the engine-man that-he has' dition, a "circuit "is'closed for the electro-" magnet 11 -follows-:-Positive p ole of=-battery' 43, lead 60, supporting bracket 65,sh0e 5. V), ramp8, terminal strap 32, 33, contact '25, leaf springQS, contact'Qt, electromagnet ll'to rail Q'and frame of engine to whi ch the negative p o'le o't' battery 43 is connected.

Electromagnet 11 is thereby energized-but is immediately ale-energized when *the train stood when the operation oi the system islea-ves ramp 8 due to its normal locking'c'ir- 7 tact 26, the "time elementdevice=being there- This locking circuit eX- t'en'ds from rail 2, over battery 58,1'armatime 59, contact '26, lead 69, contacts 13, 14,

train reaches ramp 9, the shoe 49 is defi'ected outwards 'and thecontact 54 is theremagnet 341 is broken, this circuit being 1 traced as follows :--Ne'gative pole ot'battery stances, battery 58 will be connected 'direct' to ramp 7 through 'armature59 of track relay6 and-its workingcontact, and contacts "26 and 27 in theirdotted position, terminals 30 and 31.

53, contact 65 ,-armature 35, contact 66, left hand winding of electromagnet 34, brush 54E, brush 53, contact deviceolflead 69'to. positive pole of battery 43. circuit is completed from positive pole of battery 58, armature 59 and its Working contact, contacts 96 and 27in the operated position, terminal straps 3O and 3t, ramp 9,

1 electromagnet 11., back to rail 2. 7 When the S however,

shoe 4L9, s'upp'ort ti t, right hand winding of electromagnet 34 to the frame of the engine andthen'ce to rail 2 and negativepole' of bat tery 58, electromagnetB iis maintained energized and the valve 36 remains closed. On passing the ramp 10 exactly the same Circuits are completed the ramp'lt) being connected to battery 58 through armature 59 and contacts 26 and 27 in their operated position. hen the train. passes over the rails 3 and L, the track circuit relay 6 is-de energized, thereby breaking battery connection with. the ramps 7, 9 and 10 subsequently thehome and starting signalsare returned to the normal or danger so that the connection of battery 58 with the ramps 7, 9 and 10 is broken at contacts '26 and 27.

i It will next be assumedth'at the home and distant signalsare" at danger when the train is approaching. Consequently, when,, the shoe 49 engages'with the ramp 7 and is deflected inwards, battery 58 will be disconnected from the ramp 7 and therefore there will be no circuit for the left hand winding of the electromagnet 38, and as the circuit of the right hand winding and the winding of relay 66 is broken at brush 55 the armature 67 will fall away and armature 39 will be released, thereby permitting the valve 40 to open and allowing air to enter through the opening 41 and past the reed 42.

The ellect of this is to give a partial application of the brakes thereby somewhat restricting the speed of the train, and at the same time, by causing the reed 42 to vibrate due to the passage of the air, a warning signal is given to the driver. As the armature 39 has been forced upward by the pressure of the outside air on valve 40, the circuit tor the bell. 44 will not be completed. It will therefore be appreciated, that by this means a different signal is given to the engine man according as to whether he is passing a distant signal at danger or at clear.

The engine man can remove the partial brake application by pressing on the diaphragm 46 thereby closing the contact springs 68 so that once the shoe has been restored to normal the circuit of the right hand winding 01 the magnet 38 is again completed from positive pole of battery, lead 60, contact device 61, brush 53, contact plate 56, brush 55, right hand winding of electromagnet 38, contact 68 to negative pole of battery and the armature 39 attracted to close the valve 40. If desired, arrangements could be provided whereby this restoration of the armature 39 and the removal of the partial brake application could only be effected it the engine man had himself taken steps to apply the brakes. Such an arrangement is not described as means for bringing the idea into efiect may be readily developed by those versed in the art.

The restoration of the armature 67 ot the electromagnet 66 can be ellected by pressing the diaphragm 45 as will be readily understood by reference to Figure 3.

The engine next approaches the ramp 8 where the shoe 50 is deflected inwards. In this position, the circuit will first be cornpleted as beforedcscribed for the electro magnet 11. which attracts its armature 12 and at contacts 13 and 14 closes a locking circuit which may be traced as followsz Battery 58, armature 59, and its working cont-act, contact 26 in its position shown in full lines, lead 69, contact 13, armature 12, contact 14, electromagnet 11 to rail 2 and back to negative of battery 58. Electromagnet 11 is therefore maintained energized until either the starting or both the starting and home signal levers are operated to the clear position or until the train passes over the track 3 and 4 and short circuits the track relay 6, so that the armature 59 falls away. Armature 12 by its attraction puts a tension on the open helical spring 15 to cause the toothed sector 16 to rotate about its pivot 17; consequently, the sector 16 cominences to travel slowly towards contacts 21 and 22. The first ettect of this is the opening of leaf spring 3 of the initial energizing circuit of the electromagnet 11 through contacts 24 and 25. It the train exceeds a given speed for which the disance between the ramps 8 and 9 is chosen and the time element device T is set, it will reach the ramp 9 before the contacts 21 and 22 are closed.

Consequently when. the shoe 4-9 is deflected outwards by the ramp 9, there will be no flow of current from the ramp through the right hand winding of the electromagnet 34 and as the left hand winding will be de-energized due to brush 54 being isolated, the armature 35 will fall away and the valve 36 will open to admit air to the vacuum chamber 3"? and cause a full emergency application of the brakes. If on the other hand, the train was traveling below the predetermined speed, then the sector 16 would have engaged with the contacts 21 and 22 and battery 58 would be connected in the following circuit to the ramp 9; battery 58, armature 59 and its working contact, contact 26 in the normal position corresponding to the danger position of the signal, lead 69, contact 13, armature 12, contact 14, contact 22, toothed sector 16, contact 21 to ramp 9, shoe 49, bracket 64, right hand winding of of electromagnet 34, to frame. Electromagnet 34 would therefore be maintained energized, and consequently the brakes would not be applied.

It will be seen that in case a train should be present in the section of track 3, 4, when shoe 50 engages ramp 8, the track relay 6 would be (lo-energized and consequently the locking circuit for magnet 11 would be opened at armature 59. Consequently, in this case contacts 21 and 22 cannot be closed however slowly the train is proceeding and a full. emergency application of the brakes will take place at ramp 19 as described above.

lVhen the train approaches the ramp l0, this ramp depends solely for its connection to battery on the operation of both the home and starting signal levers, it will be evident that as this ramp is shaped identical with the ramp 9, there will be a full brake application whether or not there has been a full brake application at ramp 9. Usually, the ramp 10 will be placed at the home signal and adapted to pull up trains travelling below a certain speed within the block clearance, while trains exceeding that speed will be tripped. at the ramp 9. Obviously, additional' ramps to suit various speeds coul'd'bef is connected. direct to the ramps 9 and 10' and therefore the train has. a free passage and can speed up without any possibility of the brakes. being applied.

As. soon as the train passes over the rails 3 and 4, the track relay 6 is short circuited and at 59 the battery connection to the ramp 9 is broken and also the time element device is deenergized and restored to normal in readiness for the passing of the next train. An important feature of this construction is that the ramp 9'is always in the danger condition except for the short interval which elapses between the time when the train passes the ramp 9 and the time when it reaches the rails 3 and 4. The time element device is firstenergized by a supply of energy on the train (battery 43) is subsequently maintained energized independently thereof by a second source of energy (battery 58) and issubsequently permitted to restore to normal immediately the latter source of energy is removed. Further its restoration being under gravity control, there is no danger of brokensprings or the .likepreventing its return. 'It willfbe obviousthat that part ofF-i-gure 1 which includes the ramps 8 and 9 the time element device T and the small insulatedtra'ck. section 3 and 4 may be utilized. independently of the signalling system. in. any place where a permanent speed reduction is required, for instance, it may be applied at the turn out of junction or where the configuration of the line is on a sharp curve; the circuit arrangements would sucha casesimply consist of a straight connection from the front contact of armature 59 direct to contact 13, and the contacts 26 and 27 would be eliminated. I

For single line working, it will be understood that a set of ramps similar -to the ramps 7, S, 9 and 10 would be provided at each end of the track and consequently, in order to prevent the ramp 8 becoming equivalent to the ramp 7 for the reverse direction of running a special lever 28, 29 is provided which takes the positions shown infulllines for the direction of running described and the position shown in dotted lines for the reverse direction of running. It will thus be appreciated that in the reverse direction of running, the ramp 8 is connected direct to battery 58 and consequently the brakes will notbe applied to the train running in the reverse direction when passing-the ramp 8,

and further, the connection between the ternzinals 39 and 31. will be broken. Special interlocking meanswould be provided to ensure conformity between theposition of the special lever with the starting and home signal levers.

It will'be understood that the brakes will be controlled in'the usual way for trains running in. the direction for which the ramps are set. In case of engines travelling in the reverse direction, say for instance, tender first, then. obviously it is desirable. to reverse the current connections to the shoes, and this is effected by means of' a reversing switch 4'8 with movable contact arms 74t. Asbefore mentioned, the shoes 49 and 50 are of. identical. construction and as these are provided with .four different contacts one of which is used. for two different purposesaaccor'dingto the direction of" running a switch having 5 contact arms is required. The reversing switch may be conveniently controlled in accordance with the direction of rotation of the axles or with the position of the engine reversing gear. Consequently, thearrangement of the ramps 7', 8', 9, 10 shown in Figure 1, will control the application of the brakes in the manner described for trains running inthe direction of" the arrow whether tender first or otherwise, while by providing the speciallever controlling contacts 28 and 29v only that set of ramps which respond to the direction of running will be operative to control a train 'for single'line working.

Referring'to Figure 3 a brief description will be given of various details for carrying out the invention in a preferred manner.

For instance, in orderto render the valves 36and 40 and. also the special valve 7 5' the purpose of which will be described later,

as effective as possible, they are provided with a comparatively sharp engaging surface adapted to embed on to rubber rings 76, '77 and 78 respectively. Consequently, very little.f0rce other than that required to overcome the pressure of the outsideair will be required to ensure an effective seal. The valve 40 is adapted to be, replaced on its seating by the simple attraction of the armature 39 which is :allowed a comparatively limited movement this being possible in View of the valve 40 being provided for applying a partial brake application only.

The valve 36 is to applythe full :brake application audit is only to be applied in cases of emergency; it is necessary that this valve should only be replaced with considenable difiiculty and. that the operation must take some considerable time. This is effected by the mechanism 47 which consists of a handle 7 9 cranked to a shaft onwhich is fitted a small. pinion wheel 81 geared with a large toothed wheel 82 secured on the shaft of the special Valve 75 having athreaded portion 83 engaging with the. frame to ensure a vertical movement of the valve on rotation. The operator in order to replace the valve 36 on its seating has to turn the handle 79 thereby opening the valve 7 5 until its end 83 engages with the armature and forces this armature upwards and also forces the valve 36 back on to its seating 76; the armature 35 being restored to normal completes at contacts and 66 the circuit of its normal energizing winding which therefore holds the armature 35 in its operated position and maintains the Vttli'a' 36 closed. The brake application however is not yet removed as the chamber 37 is open to the atmosphere through the valve and ports 100 in the cover on the gear 82; it is still further necessary for the engine driver to rotate the crank 79 so as to bring the valve 75 back on to its seating 78. It will therefore be appreciated that it is practically impossible for the engine driver to remove the brakes until they have been on for a sufiient length of time to bring the train to a standstill. If desired the arm 79 could be secured with a seal so that a record would be given whenever it was used or a record could be made in any other convenient way.

Another feature of the invention is the construction of the shoes 49 and 50. As previously mentioned these shoes are normally pivoted at 51 and 52 so as to move at right angles to the direction of the running of tne train. The bearings supporting the shoes are in turn mounted on horizontal shafts 84 and 85 at right angles to the direction of the running oi the train, on which shafts are fitted springs 86 engaging with collars 87 thrusting these collars against the Sides of the bracket 89 fixed to the engine. Interposed between the collars 87 and the bracket 89 are friction discs 88 so that the bracket supporting the shoe 51 is enabled to rotate about the shaft 8% but only atter overcoming considerable friction. On the bracket 89 is secured a contact device 61, having a fixed contact 90 and a movable contact 91 which latter contact is adapted to be actuated by the rod 92 which passes through holes in the main frame and in the friction disc 88 into a recess in the flange of the shaft 84, so that whenever the shaft 84 is moved from normal position, the rod 92 is forced out oi the recess in a longitudinal direction and causes the contact 91 to break connection with the contact 90. As this contact device 61 is in the normal energizing circuit of the magnet maintaining the valves 36 and 4:0 closed, it will be appreciated that if the shoes 19 and 50 strike obstacles with suflicient force to cause the shoe 19 to rotate other than in the direction effected by the ramps, then the brakes would be immediately applied. Butter springs at 93 and 91 are provided to maintain the shoe 19 normally in a. central position.

Referring to the accompanying drawings,

7 to swing.

Figure 4 illustrates diagrammatically the operation of the train control system embodying the principles of the present invention; ldigure 5 shows a sectional elevation of the improved time control element, F i 'ure 6 shows a side section with mechanism and coils removed, Figure 7 shows an inverted plan with the base removed, while Figure 8 shows a side sectional elevation.

Before proceeding with the description of the operation of the system, the construction of the time control device illustrated in Figures 58 will first be explained.

The time control element consists of an clectromagnet controlling an armature 121. This armature 121 is pivoted at 124 and is provided with an arm 123 having a curved surface 125 on one side and a projecting member 126 on the other side which normally engages with a projection 127 on the shaft 128 carrying the balance weight 129.

A shaft 130 pivoted in brackets 131 and 132 carries a rachet wheel 133 and a cylindrical disc 134, while a bracket- 135 loosely supporting a roller 136 in close proximity to the surface of the disc 134 is pivoted on the shaft 130. Normally the roller 136 under gravity control rests in the position shown, although this position may be adjusted by the screw 137 to the left of that shown. When the electromagnet 120 is excited the armature 121 with its arm 123 moves a short distance suiiicient to permit the projections 126 and 127 to disengage so that the balance weight 129 can commence At the same time the arm 123 moves the roller 136 into engagement with the surface of the disc 131. This movement is suiiicient to break the connection between the contacts 138 and 139 (Figure 6) and the resting contacts; 140 and 1 1-1 respectively, but not sulhcient to permit the contacts 1 1-2 and to make connection with their working contacts 144. and 14-5 respectively. The release oi" the balance weight 129 causes this member with the shaft 128 to swing to and fro.

As in a. well known clock work movement a contact is closed for the elecirmnagnet 146 in circuit with a primary cell through the balance spring 147, shaft 128, contact 1 18 (Figs. 1, 7 and 8) and contact 1-19 supported by a leaf spring and arranged so that the shaft only makes electrical connection when moving in one direction. l llectromagnet 146 as is well known serves to attract the soft iron pole piece carried by the balance weight 129 as this approaches its core so maintaining the balance weight in movement. On the shaft 128 is a cam 150 adapted to engage with a roller 151 supported on a bracket 172. The bracket 172 pivoted at 173 and carries at its upper end a pawl so that the cam 150 by acting on the purposes.

a number of terminals by means or which roller 151 causes the pawl 170 to advance the ratchet wheel 133' and with it the disc 134' one step for every complete swing of the balance weight 129; The movement of the disc 131 is imparted to the roller 136 which advances step by step between the surface of the cylindrical disc 134 and the inner surface 125 of the arm 123 which is so shaped as to exert substantially uniform pressure on the roller 136 during its movement.

After a predetermined time the roller 136 advances to a position opposite recess 152 where the arm 123 can move freely and permit the armature 121 to complete its movement and cause the contacts 1.42 and 143to engage with the working contacts 144' and 145 (Figure 6). When the electromagnet 120 becomes de-energized the arm 123 falls back to its normal position releases the roller 1 25 which immediately is restored tonormal by gravity and permits the projecting member 126 to engage with the projection 127 when the balance weight 129 reaches the, position shown in Figure 5 of the drawings. It will be noted that the'projection 127is cam shaped in order to prevent any damping'of the movement of the balance weight 129 so that it is assured. that the member 129 will by its inertia, reach the position in which it is to be locked readyfor a ire-operation ot' the device. In Figure 1 it will be noted that an arm 122 is shown engaging at its extreme end with the member 129 at itsouter edge, and while this serves 1 for diagrammatic purposes, such a construction is not desirable nor is it found to be so satisfactory in practice as thatshown in Figure 5. It, might be mentioned that all the working parts shown in Figures 5, 6, 7 and 8 are supported by means of brackets 177 and 178 from the cover 153 of a box 154: having glass faces 155by which the operation of the parts may be observed for inspection The cover 153 is provided with connection may be made both to the contacts and to the electromagnets 146 and 120. In order to render the construction weatherproof a rubber or like gasket 156 is provided between the lid 153 and the box 15 1. The bracket 177 and 178 carries ball bearlugs 17 5-and 176 respectively on which the shaft 128 can oscillate with negligible damping.

A modification ol the train control system described with reference to Figs. 1, 2' and 3 will now be described. This system differs from the previous system in that, in place of ramps, mechanical tram stops are used such as are described, for instance, in British Patent No. 6807/14; while the initiation of the operation of the time control device is eflected by a circuit being closed by the train between a short insulated rail and anotherr'a'il; Another feature is the 'arrangementofthe circuits by which the time control" device illustrated in Figs. '5, 6,, 7 and 8 is arrangedto-operate in a train control system having the features of the invention; Referring-to Fig. 1, DS represents the distant signal and H represents the, home signal adjacent a length of-track over which it is assumed that it will be desirable-to control the speed of the train. At. the home signal H, starting signal X, and advance starting signal .Y, train stops TS are fitted, while at apoint somewhat in advance of these train stops is an auxiliary train stop ATS. The train stops may be of any well-known construction which involves a mechanical engagement with apparatus on a train except that'the train stop ATS must be eleotromagnetically controlled. Thetrain stop TS may be either electromagnetically controlled or mechanically controlled andis adapted to be-brought to the off position only when the corresponding signal shows clear. The apparatus on the train is well known and need not be described, one example of it being given in the British Patent No. 6807/14, above referred to;

The auxiliary train stop is loca'ted'at a position which is determinedby the local conditions. It is assumed that a certain block clearance is allowable beyondthe home signal H 'in which a train must pull up as to pass beyond this limit when the signal is at danger is to run the danger of an accident. Consequently if the train 7 is travelling below a certain speed the train stop TS would be able to bring it tor-est within the block clearance, but if the train is exceeding a certain speed, then the auxiliary train stop ATS must comeinto action and. the'position is so chosen that if a train is going at its maximum possible speed it will always be pulled up within'the block clearance past the home signal if thebrakes are applied by the train stop ATS.

If desirable of course, other auxiliary train stops could .be provided, to correspond to intermediate speeds, but in practice one auxiliary train stop will" usually be all that is desirable. The speed of the train is estimated by means ofa time element device comprising a neutral relay R and a time control device TC which is represented diagrammatically and is illustrated in greater detail in Figures 5-8. This time element device serves to determine whether the time taken for the train to pass over a measured track which extends from the insulators 101 to the auxiliary train stop ATS is less or greater than a predetermined amount.

On the righthand side of the insulator 101 on the upper rail, a short insulated rail is fitted in the main track. This insulated rail is electromagnetically connected to a battery B and to the armature 112 of the relay R. The rail 111 which extends from the insulator 101 to the left of the rail 110 beyond the auxiliary train stop ATS to the insulator 113 is also insulated and is electromagnetically connected to the working contact 114 of the armature 112. BVV represents the block wire which extends from one signal cabin to the next in series with polarized relay PR. This relay can only operate when the direction of current in the block wire corresponds to the signal train on line having been set up. Under these circumstances armature 116 is attracted and a circuit extends from rail 117 through armature 116 and its working contact, relay R, battery B to insulated rail 110. This circuit obviously cannot be completed until a train connects the rail 110 with the lower rail 117.

It will be assumed that the signals are at danger and the train has advanced beyond the distant signal. Under these circumstances the engine-driver should have reduced the speed of the train according to instructions. But whether or not he has done so, as soon as the front wheels of the train pass beyond the insulators 101; the rails 110 and 117 are electrically connected together and the relay .lrt is energized in the previously traced circuit. The relay then attracts its armatures 112, 118 and 119. At armature 112 it completes a locking circuit for itself independent 01' the rail 110 which may be traced as follows:-R ail 117, armature 11.6 and its working contact, relay R, battery 13, armature 112 contact 114, to rail 1.11 which is now connected by the train to the rail 117. The relay R therefore. remains energized until the last carriage of the train passes beyond the insulator 13. At its ar mature 119, a circuit is closed for the electromagnet of the time control device T C as tollows:Positive pole of battery ll, electromagnet 120, armature 119 and its working contact to'negative pole of battery B. The electromagnet 120 energizes and attracts it. arn'iature 121. This armature is provided with two arms 122 and 123, the arm corresponding" to the projection 126 (see Figure 5), while the arm 123 is substantially identical to that described with reference to Figures 5-8. The consequence is that the balance weight 29 is released and commences to oscillate under the control of the electromagnet 146. By means of its cam 150, the balance weight 129 causes the roller 151 by means of the pawl 170 to advance the ratchet wheel 133 step by step and to rotate with it the cylindrical disc 134-. As the arm 123 has also moved suiiiciently to force the roller 136 into engagen'ient with both the surface of the arm and the surface of the cylindrical disc 134, the roller advances and after a predetermined time comes opposite the recess 52 when the armature 121 is no longer prevented from moving to its fully attracted position to engage with the contacts 144 and 145 when a circuit is closed as follows: positive pole of battery B contact 144, armature 121, contact 145, contact 155, controlled by auxiliary train stop ATS, winding 157 of the electromagnet controlling said train stop, armature 118 to negative pole of battery B which is connected in series with battery B The train stop magnet is thereby excited and its arm moved to the off position. Now it the train had been exceeding a predetermined speed it would have reached the auxiliary train stop before this operation could have taken place as the time for the roller 136 to come opposite the depression 152 has been set to take a predetermined time according to the estimated speed which the train must not exceed; consequently the train on reaching train stop ATS would have its brakes applied. 11, however, it has been travelling below the predetermined speed, then it will not be affected and will only have its brakes applied if it passes the train stop TS. Normally the train should be pulled up at the home signal but if it should pass the train stop TS, its braking will be automatically applied; however, its speed will not be high enough to allow it to travel beyond the block clearance under these conditions.

On the assumption that everything is clear, then all the signals governing the motion of the train (in addition to the home signal, the starting signal X and the advance starting signal Y are also shown) will be at the clear position. Contacts 160, 161 and 162 which represent contacts controlled in the well known manner at the signal levers will be closed and a circuit for the electromagnet 120 may be traced follows: positive pole of battery B, electromagnet 120, lower rail 117 contacts 160, 161 and 162 in the operated position to negative pole o1 battery B; electron'iagnet 120 will therefore he energized as soon as the signals are lowcred, so that before ever the train reaches the rail 110 the roller 136 will have approached if not actually reached, the depression 152; consequently the arn'iature 121 will make contact with contacts 144 and 145 some time before the train reaches the train stop ATS. The circuit of the auxiliary train stop l TS however is not completed until relay R is energized as this is open at armature 1S and as this relay can only be energized by a train connecting rail 110 with rail 117, it follows that the auxiliary train stop will only be in an 011 normal position during the passage of a train over the rail 111. The auxiliary train stop ATS is provided as usual with a contact operating device corresponding to its oil and its on positions, the armature 155 being adapted when the train stop is in the off position, to be withdrawn. from connection with its resting contact as to bring into circuit a resistance 1G3 whereby the current consumption is reduced, it being understood of course that a 1 considerably heavier current is required for energizing the train stop 157 than for maintaining it in its of? position. Armature 164 is provided for detection purposes, positive or negative battery being connected by armature 164 from the rail 11'? to an auxiliary conductor 165 extending to a detector DE in the signal cabin, so that the position or the train stop may be observed.

It will. thus be appreciated that by means oi the present ii'ivention, a time element device has been produced which always starts under the same conditions, which rcquires very little energizing current, just suliicient to cause the roller to engage between the disc and the auxiliary arm of the arn'iature while the timing is highly accurate and the exact amount can be adjusted by varying the starting position of the roller. A single dry cell is snilicient for maintaining the oscillator and under orc i.

nary circumstances should last for several yea rs.

lt will be appreciated that by means oi? the invention a system has been evolved which reliable, adapted to interfere with the normal running of the trains as little as possible, while providing a maxin'inm amount oi safety, and further, the apparatus used is simple while the time element device for determining the speed of the train is accurate and requires little operating current, thereby ensuring that the maintenance costs will be low. i

it should be mentioned that the part of the invention comprising the track circuits, the elcctroinagnetically controlled train stop and the time element device with the neu. lral rela may he. applied to any part of the line where a permanent speed reduction is required. as on curves or the turnout oi a junction, while the provision of two trainstops, one controlled in accordance with the speed oi the train may be provided at terminal stations to ensure thata train (.loes not enter at too high a speed; such arrangements would oil? course be entirely in dependent of the normal signalling system.

What we claim and desire to protect by Letters Patent .is:

'1. A train control system comprising a track. a time element device located at the side oi the track. apparatus controlled by application of the brakes it the speed of the train is below a certain value and manually operated signalling means operable to con- .trol said llP-Qill'll'll? to prevent'the applicaoperated si nalling means adapted in addi-.

tion to controlling a visual signal to control said apparatus so as to prevent the application of the brakes when conditions are such that a train can pass without 13estriction.

3. A train control system comprising a track, apparatuslocated at two different points z-dongside said track for effecting the application of the brakes of a passing train, a time element device located at the side of the track and set in operation by the train to control, after a predetermined time, the apparatus which .islocated at that point which is nearer to an approaching train, means for controlling the apparatus which is located at that point which is further troni the approaching train, and manually operated signalling means adapted in addition to giving a visual signal to control said apparatus when conditions are such that a train can pass without restriction.

" l. A train control system comprising a track, apparatus located at two different points alongside said track for effecting the ap 'ilication ol thel'nrakes ot a passing train, a time element device located at the side of the track and set in operation by the train to control, atter a predetermined time,

to control said apparatusindependently of said time element device, and means for controlling the apparatus which is located at that point which further from the approaching train.

5. A train control system comprising a track, apparatus located at a given point alongside said track for controlling the application oi the brakes of a passing train, a time element device adapted to be set in op eration when a train passes a certain point and maintained in operation independently of its initial energizing source, a member movable under a continuously acting restorinc; force and adapted to be controlled by said time element device when in operation to prevent said apparatus causing the application of the brakes ii the train reaches a given point after a predetern'iined time, and releasing means controlled by the train on passing another point to effect the restoration of the n'io'vablc member to its normal position.

6. A train control system comprising :1 track, apparatus located at a given point alongside said track 'lor controlling the application of the brakes oil a passing train, a member adapted to be operated against a continuously acting restoring force when a train passes a certain point and maintained in operation, means under the control of the train after it has passed beyond the given point to permit the restoration of said men's her under the control of said force and a time controlling device adapted to be set in operation by the first member also againsta continuously acting restoring force to so afl'eet said apparatus alter a predetermined time as to prevent the brakes being; applied.

7. A. train control svsteni comprising a track apparatus located a1 a given point alongside said track tor controlling the a plication of the brakes ot' a passing train an electrically controlled time element device adapted to have its circuit closed when a train passes a certain point, circuit closing members adapted to be operated when said device is energized to close a point in an independent circuit for maintaining said device in operation, a movable member under a continuously acting restoring 't'orce adapted to be controlled by said time element device when in operation to prevent said apparatus causing the application ol the brakes it the train reaches a given point after a predetermined time, and means for opening the circuit of the time element device when the train passes another point to a il ect the restoration of the movable member to its normal position.

8. A train control system comprising a track, a. ramp located at a given point:- alongside said track for influencing the apparatus controlling the application of the brakes on a passing train. a second ramp located at a second point alongside said track in the direction oi? an approaching train, an eleetrically controlled time element device adapted to have its circuit completed when a train passes the first ramp and maintained in operation in an l1l(l(-}]')9i1(l0fltcircuit. a movable member under a continuously acting restoring force adapted to be controlled by said time element device to complete a circu t to said second mentioned ramp and thereby influence the brake controlling apparatns on the train it it has not reached the given point before a predetermined time to prevent the brakes being applied and means for opening the independent circuit when the train passes another point to allect the rescation of the brakes ot a passing train and means controlled by said time element device to render said brake controlling means non-effective alter a predetermined time.

10. A train control system comprising a track an electroinagnet alongside said truck. a contact member adapted to be engaged by a passing train to complete an envrgiring circuit for said electron'iagnct', an armature for said electroniagnet a time element device adapted to be set in. operation when sa d armature is attracted. means tor contro ling: the application ol' the inches of a paasin i train, means including electrical cPrcuit connections for controlling the applicatimi oil the brakes cl. a passing train. and contact making devices controlled by said time element device to make certain ol said connections and thereby prevent the application (it the brakes a'l tie' a predetermined time.

11. A. train control system comprising: a track, an electromagrne' alongside said track, an electrical circuit including said electromagnet and adapted to he completed by the passage ol :1 train. a :-.-'.:ro:nl emrtrical circuit adapted to be -l'l'll')l(?i'0i'l when said Cl0(f't'1'()]'ll& l'1l(l' is elierg irrd to n'iaintain it energiycd independentl r ol' sa d first mentioned circuit for controlling: the applicacation oi the lunkcs oi a passing lil'tlln, time element 'irc adapted to be set in mieration when said clcrtroniagnet is cnergized. contact making devices ontrolled by said time element device it con'iplete said circuit and prevent the application of the ,rakes alter a prer'letcrmired time and (in cult opening means controlled by a missing train to elicit the opening of sa d Fecoi'u'l circuit to restore the time clement device to normal.

'12. A train control system comprising a track. an elcctroinagnet aonggsidc said track. an electrical circuit including said electromagnet and adapted to be comple ed by th passage or a train. six-0nd elect ii -i'ru l adapted to llQ completed when said electromagnct energized to maintain it r-nere'iyz-ed indepci'identlr o l said first mentioned circuit for controlling the application oi the lHtrlidH of a passing); train, a time clement devic adapted to be set in operation wnen said loo electromagnet is energized, contact making devices controlled by said time element device to complete said circuit and prevent the application of the brakes after a predetermined time, a short portion of track insu-' lated from said first mentionedtrack and located beyond the point where the brakes are adapted to be applied, a source of electrical energy connected across the rails of saidtrack, an eh-ictromagnet also connected across the rails of said track and adapted to be norn'nilly energized by said source of electrical energy, a contact adapted to be normally closed by said electromagnet to normally maintain the second circuit closed and to efl'ect its opening \vhenshort cireuited by a passing train.

13. A train control system comprising a track, apparatus located at a given point alongside said track for controlling the application of the brakes ot' a passing train, an electromagnet adapted to have its circuit completed when a train passes a. certain point, circuit closing members adapted to be operated when said electromagnet enersized to closea point in an independent circuit for maintaining said electromagnet energized, means operated when the train passes a point beyond the given point for positively opening said independent circuit for said electromagnet and a time controlled device adapted to be set in operation due to the energization of said electron'iagnet and to operate against a continuously acting restoring force to so allect said apparatus after a predctermined time as to prevent the brakes being applied.

14. A train control system comprising a track, a ramp located at a given point alongside said track for controlling the application oi the brakes ot a passing train, an electromaanet adapted to havevan energizing circuit completed when a train passes'a certain point and to be maintained energized in a different circuit until the train has passed the given point, and a time controllingdevice adapted to he set in operation due to the energization of said electromagnet and to operate against a continuously actlng resorting force, to connect a source of electrical energy to said ramp alter a predetermined time for the nn-pose of preventing the application ol the brakes.

15. A train control system comprising a track, a ramp located at one side of said track. an electrically controlled time element device connected to said ramp, and adapted to be set. in operation when a train passes said ramp, :1 second ramp situated ditferently from said first ramp with respect to the track and arranged to control the application of the brakes ot' a passing; train unless connected up to a source of electrical energy, and adapted to be so connected by said time element device after a predetermined time, a third ramp situated and vent a train passing a given point whatever its speed 1f the brakes are applied at that point, While the third ramp is located at such a position as to prevent the train passing the given point it the train has taken a longer time in passing from the first to the second ramp than the time element device has taken to operate.

16. A train control system comprising-a track, a shoe on a passing train, a ramp at the side of. said track for controlling the movement of said shoe in one direction so as to cause a partial application of the brakes and a second ramp at-thie side of said track for deflecting the shoe in another direction to cause the full application of the brakes.

17. A train control system comprising a track, a shoe on a passing, train, a ramp curved so as to cause said shoe to be deflected in a horizontal direction at right angles to the track to ause the partial application of'the brakes, and a second ramp curved in such a manner as to cause the shoe to be deflected in an opposite direction to the first ramp to cause the full application of the brakes.

18. A train control system,comprising a track, a ramp located alongside said track, speed determining apparatus adapted to be set in operation when the train completes a circuit through said ramp, and a second ramp on the other side of said track adapted toefi ect thea-pplication of the brakes unless the'speed determined by said speed determining apparatus is less than a predetermined amount.

19. In a. train control system, a locomotive having a shoe secured thereto and adapted to be deflected in different directions by ramps on the track, brake controlling apparatus controlled by said shoe to cause the full application of the brakes if the shoe is deflected in one direction and the partial application of the brakes it the shoe isdeflectcd in the other direction.

20; A train control system comprising a locomotive a shoe secured to said locomotive and adapted to be deflected in different directions by ramps on the track, normally energized electromagnets tor controlling the partial or tull, application of the brakes respectively and means for opening; the circuit of one or other of said. electroniagnets to cause the full or partial application of the brakes according to the direction in \vhich the shoe is deflected. V

21. A train control system comprising a lift] Hill said locoto he deramps on locomotive two shoes secured to motive one of which adapted lected in dil'lerent directions by the track to cause either the full or partial application of the hralves While the other shoe is connected up to initiate the operation of speed determining ap 'iarat-us.

22. A t'ain control systen'i comprising a locomotive, shoes located one on each side ot said locomotive and adapted to be defiectcd in opposite directions one of whi h controls the circuit oi electromagnets controlling the application of: the brakes WllilC the other controls the circuit of speed determining apparatus, and switching means operable to change the electrical connections to the shoes in accordance with the direction in which the t'ain is running.

23. A. train control system comprising; a track, an electromagnet alongside said t *ack, an electrical circuit int-hiding: said electromap'net ada 'ited to he coi'npleted by the passage ol :1 train. a quick moving armature on said electromagnet, a time control device. spring connecting means hctwcen said armature and said time control device, adapted to :ausc said time control device to he set in operation when said armature is attracted, \vhile permitting: the armature to make a movement indepemlentlv of the time control device means for controlling the application of the h'akes on a passing train and means controlled by said time elerentdevice. to malro said hrike controlling means non-effective alter a predetermined time.

24. A train C(Jl'llil'Ol. system comprising a track, an eleclroinag nel alongside said l'aclt, an electrical circuit including: said electroniaanet adapted to he completed hy the passage of a train. a quicl; n'ioving armature on said electronmgnet, a time control device. a spring: connecting said armature to said time control device to cause said device to he set in action when said armature is at-t'acted. means for controlling the application oi the hraacs of a assinp; train and means controlled hv said time element device to render said hralie controlling means 110ii-ciict3ti8 after a predetcrn'iined time.

A train control svsten'i comprising a track an electromagnet alongside said track, a ramp alongside said track. an electrical circuit connecting said electromae net with said ramp and adapted to he con'ipletcd by a passine train to cause the energization of said electromagnet, an arn'iature for said olectromagne: contacts on said armature adapted to close a point in an independent circuit for maintaining said eleetromagrnet energized, a time controlled device adapted to be set in operation when said armature is attracted, means for controlling the applications of the brakes of a passing vain and masses system comprising a alongside said tracl-r,

etieci the icai on or no hralccs a source oi clcctr l. energy and contact making -hers :nlaptcl to he closed vvhcn said t 2 element dcv co has heen in operation time to connect said source to said ramp and thcroplication of the hralies ol:

1 ti-determined or electrical energy by prevent the a sing train.

A train control system comlin'ising a track, a ramp locatco alonsrside said t 'acli J. fl i V and adapted lo he controlled to cause the i application of the hral-zes ot a pass traii irrespective of the speed oi the l ramp located alongside said iled to he controlled to ellcct i itcation of the brakes it the tra'u escorts a certain speed and a third ramp located alongside said track adapted to he controlled to effect the full, application oi? the h 'alces whatever the speed of the train.

21*. fr train control system comprising a trade a ramp for controlling the partial appli 'al'ion o l the hrakes oi a passing; traiin a second ramp l'or initiating the opcratiim of s iecd determining ap aralus a third ramp adapted to control the lull application of the l,)l'2ll 0 it the speed of the train is greater than a certain amount as determined hy said speed determining :upparatus, and a Fourth ramp ada itcd lo conlrol the "full, application of the hralics irr(. spectivc of the spe d of the train,

29. A train control system comprising a tracle a ramp 'lor controlling the partial application of the brakes a second ramp for initiating the operation oi, a time control device, a third ramp l'or cii'eclinpthe tall application ot the hral es when the train reaches said third ramp he'l orc the time element device is fully operated, and a fourth ramp controlling the full application oi" the brakes.

305A train control. system comprising a track a. ramp located along ide said, i 'ach and adapted to he controliel to cause the partial applicatimi of the l'n-ahes of a passing train irre pective oi the SfjGQd of: the train, a second ramp located aloi'icside said tracl: and adapted to he controlled to eliecl the full application of the hrali'es ii the train exceeds a certain speed and a third ramp also located alongside said track adapted to be controlled to effect the full application also fill

lIO

of the brakes Whatever the speed of the train, and means for connecting a source of electrical energy to said ramps to prevent the application of the brakes being effected.

3].. A train control system comprising a track, a ramp located alongside said track causing the partial application of the brakes, a second ramp located in a different position with respect to said track for initiating the operation of speed determining apparatus and a third ramp shaped dilterently from said first ramp to cause the :full application of the brakes of a passing train it the speed of the train is greater than a predetermined amount.

32. A train control system comprising a track, a curved ramp located at the side of said track for controlling the partial appli cation of the brakes, a second ramp curved similarly to said first ramp on the other side of said track for initiating the operation of speed determining apparatus, and a third ramp located similarly to said first ramp but curved in an opposite direction with re- '.;i spect to said track for controlling the full application of the brakes as determined by said speed determining a )paratus.

33. A train control system con'iprising a ran'ip adapted to control the partial application of the brakes, a second ramp, an electromagnet, circuit connections extending between said ramp and said electromagnet and adapted to be completed by a passing train to cause the energization of said electromagll net, an armature controlled by said electromagnet adapted to operate contact members whereby said electromagnet is connected in a holding circuit independent of said second ramp, a time controlled element set in operation by said armature when attracted, contact members adapted to be connected up when said time controlled element has operated for a predetermined time, a third ramp for causing the full application of the brakes, circuit connections extending from said third ramp to said contacts controlled by said time controlled device to prevent the full application of the brakes it the train has taken longer to pass from the second ramp to the third ramp than the time taken for the time controlled element to operate, a fourth ramp for controlling the full application of the brakes, signal controlling means, contact devices operated by signal controlling means to connect a source of electrical energy to said first, third and fourth ramps to prevent the application of the brakes if the signals are operated, and circuit opening means controlled by a passing train to open the holding circuitof said electroinagnet to permit said electromagnet to become de-ener 'ized and the time element device to return to its normal position.

Signed by me at Liverpool, England, this 12th day of: October, 1921.

ALFRED ERNEST HUDD. Si ned by me at Liverpool, England, this 12th day of October, 1921.

ARTHUR FRANK BOUND.

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