US2826686A - Control apparatus for highway crossing gate and signal - Google Patents

Description

March 11 1958 c. w. FAILOR CONTROL APPARATUS FOR HIGHWAY CROSSING GATE AND SIGNAL Filed 001;. 25, 1951 5 Sh ets-Sheet 1 INVENIOR. Charles W Halon w x uzdt HIS arrow/1 mm Q ||ll| llllllll llNmlllllL RN N March 11, 1958 c. w. FAILOR CONTROL APPARATUS FOR HIGHWAY CROSSING GATE AND SIGNAL 5 Sheets-Sheet 2 Filed Oct. 25, 1951 R N M W lllllvvlllL Q E S B fi INVENTOR. Charles W Fzilor'. BY

H15 ATTORlViY March 11, 1958 c. w. FAILOR 2,82

CONTROL APPARATUS FOR HIGHWAY CROSSING GATE AND SIGNAL Filed Oct. 25. 1951 s Sheets-Shest 3 0012 amt Closgc? 1'12 6Z0$ed ('11 Jimmy. Lowenmy QQLMQNN Q IN VEN TOR.

Chables W Fallon 7 H15 ATTORNEY United rates CONTROL APPARATUS FOR HHGHWAY Ciiifiiifiiih-JQ GATE AND Si GN AL Charles W. Failor, Forest Hills, Pan, assignor to v -testinghouse Air Brake Company, Wilmerding, Pa a cargo ration of Pennsylvania Application Gctoher 25, 1951, Serial No. 253365 13 Claims. (Cl. 246-136)} =My invention relates to control apparatus for highway crossing gates and signals, and more particularly to apparatus for automatically controlling highway crossin gates and the signals associated therewith.

A highway crossing gate is provided with a mechanism to which there is attached an arm operable between an obstructing and a nonobstructing position. Generally speaking the obstructing position is a substantial horizontal or lowered position where the arm extends across the highway and the nonobstructing position is a substantially vertical or raised position where the arm clears highway traffic. The mechanism is biased by counterweights or otherwise to operate the arm to its horizontal position and is provided with an electric motor adapted to raise the arm to the vertical position against the force of the bias. However, in many cases the motor is. reversible and used to drive the gate arm down for at least a portion of the movement from the vertical posi tion as well as to raise the gate arm. Dynamic braking of the motor is generally provided for snubbing the arm during a final portion of the movement of the arm toward the horizontal or lowered position.

The gate mechanism is further provided with a circuit controller which is operatively connected to the mechanism to be actuated from a first extreme position to a second extreme position as the arm moves between its horizontal and vertical positions. A slot magnet is included in the mechanism to latch the mechanism when the slot magnet is effectively energized and its armature is attracted to a picked up position. When the slot magnet is deenergized the armature is released and unlatches the mechanism and it is free to be moved. In a preferred form, the slot magnet is provided with a draw up winding and a holding winding, and an armature operatively attached to a pawl which engages a ratchet, the arrangement being such that the armature is drawn up to its latching position where the pawl engages the ratchet only when both of the windings are energized, but once drawn up to this latching position, the armature is retained in that position by the energizing of the holding winding only.-

Automatic control of highway crossing gates is ordinarily effected by track circuits provided in the track in the approach to the highway crossing. The gate arm is raised and latched in its vertical or raised position as long as the approach track sections are unoccupied and is moved to its horizontal or lowered position across the highway in response to a train entering any one of the approach sections. When the train has passed beyond the intersection, the gate arm is again raised to its vertical position unless a second train or some other trafiic condition makes it unsafe for highway traffic to pass over the intersection. As a safeguard against the lowering of a gate arm of an automatically controlled highway crossing gate immediately in front of or on top of a highway vehicle, it is customary to provide visual and/ or audible warning signals which are controllably associated with the gate in such a manner that the warning signals Z,ti2$,ti8ti Patented Mar. 11, 1958 are set into operation a selected time interval before movement of the gate arm toward its lowered position is started, a selected time interval of the order of five sec onds being considered satisfactory, but other time intervals can be used. Thus, for example, a standard flashing light signal and an electric hell are usually provided and set into operation at once when a train enters an approach track section but the lowering of the gate arm is not started until the end of a selected 5 seconds delay period. This gives the operator of a highway vehicle an opportunity to stop clear of the crossing or to get out of the way of the gate arm before the arm reaches its lowered position. Generally, a flashing light signal and a steady burning red light are mounted on the gate armand are illuminated so as to clearly identify the location of the arm to highway trafiic, the steady burning lamp being preferably placed on the tip of the arm. The electric bell is preferably deenergized and becomes silent when the gate arm has reached its lowered position but the usual flashing light signals are retained illuminated until the arm is again raised.

It is apparent that with this operating condition used heretofore, a gate arm which is being raised in response to a train having passed over the intersection but has not yet reached its full vertical position, is at once lowered from whatever intermediate position it may have reached when a second train enters an approach track section during the raising of the arm. Under such circumstances, an operator of a highway vehicle has little opportunity to stop or get out of the way of the lowering arm and an accident may result due to the highway vehicle running into the arm or the arm coming down on top of the vehicle.

To overcome this unsatisfactory condition in automatic operation of highway crossing gates,'it has been proposed to provide a stick circuit arrangement for the control circuit and once the movement of the gate arm toward its raised position is started the movement must continue and be completed before the lowering of the arm is effected in response to a second train entering an approach section while the gate is being raised. With such a stick circuit arrangement some time may be lost in the raising of the gate to its full vertical position before it can be lowered again and it is necessary to increase the length of the approach track section in order to make sure that a high speed train does not reach the intersection before the gate has had time to reach its horizontal or lowered position. Longer approach track sections greatly increase the cost of such installations and also tend to cause an undesirable long warning period for slow moving trains.

Accordingly, a feature of my invention is the provision of highway crossing gate control apparatus incorporating improved means for holding the gate arm stationary at any point in its upward movement for a selected time interval and then allowing the arm to move toward its lowered position at the end of the time interval.

A further feature of my invention is the provision of highway crossing gate control apparatus incorporating novel means which automatically prevents the gate arm from descending until a selected time interval should the control apparatus be switched to its position for lowering the gate arm during the raising of the gate due to a second train entering an approach section or some other such traffic condition.

Again, a feature of my invention is the provision of highway crossing gate and signal control apparatus wherewith a gate arm that is being raised is held stationary for a. selected delay period and a warning signal not at that time being operated is set into operation when a secand train enters an approach track section, this additional a) Warning signal serving as a warning that the gates are about to be lowered.

Another feature of my invention is the provision of improved apparatus for automatically controlling highway crossing gates and the signals operatively associated therewith.

Other features, objects and advantages of my invention will appear as the specification progresses.

The foregoing objects, features and advantages of my invention are obtained by the provision of a novel and improved control circuit network which includes a slow acting control relay and a quick acting control relay, and both of which relays are made responsive to occupancy of the approach track sections, both relays being energized and picked up when the sections are unoccupied and both relays being deenergized when a train enters an approach section. Contacts of these control relays in cooperation with contacts of the controller of the gate mechanism are used to control the slot magnet of the mechanism and the associated signals in such a manner that the slot magnet is effectively energized and the mechanism latched and held stationary at any point in its movement when a train enters an approach track section during the raising of the gate arm. Furthermore, the arrangement of the circuits is such that the slot magnet is not energized until the supply of current to the motor is interrupted and undue wear and strain on the usual pawl of the slot magnet due to its being slipped over the teeth of the ratchet is avoided. An associated warning signal that is not ordinarily operated during the raising of the gate is at once set into operation when this second train enters the approach section and serves to give highway users a warning that the gate is about to be lowered. At the end of the selected delay interval the operation of lowering the gate from this int rmediate point is initiated and carried through in the usual manner. In this way the lowering of the gate arm from any intermediate point in its movement toward the raised position to its lowered position requires an interval no longer than the usual interval required for operating the gate from its fully raised position to its lowered position and approach sections of the usual length are satis factory.

I shall describe two forms of apparatus embodying my invention and shall then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1 and 2 are diagrammatic views showing a first and a second form of apparatus, respectively, embodying my invention when used for automatically controlling highway crossing gates and signals at a highway crossing of a two direction single track railway. Fig. 3 is a chart showing the positions at which the controller contacts of the gate mechanisms of Figs. 1 and 2 are opened and closed.

In each of the two views like reference characters are used to designate similar parts.

It will be apparent as the specification progresses that apparatus embodying my invention is not limited to automatic control of highway crossing gates and this control apparatus is useful where highway crossing gates are manually controlled and where a gate is controlled in part manually and in part by railway traflic.

Referring to Fig. l, the reference characters 1a and 1b designate the track rails of a single track railway over which trafiic moves in either direction and which track is intersected at grade by a highway H. This intersection is provided with two highway crossing gates G71 and G2, one on each side of the railway, two flashing light signals S1 and S2, one oneach side of the railway, and an audible signal S3 in the form of an electric bell. These gates and signals will be referred to more fully hereinafter.

The track rails in and 1b are formed by the usual insulated rail joints into three track sections ET, WT and XT, section ET being to the east or right-hand side of the intersection, section WT being to the west or lefthand side of the intersection, and the section XT being a short section which includes substantially only the intersection itself. Thus, the section ET is an approach section for westbound trains and the section WT is an approach section for eastbound trains and they would be made of a length such that a train moving at the maximum permissible speed for all trains would consume a given time interval in moving from the remote end of the section to the intersection, a time interval of the order of 20 seconds being usually satisfactory. Each track section is provided with a track circuit and as here shown the track circuits are of the usual direct current type, the circuits for the sections WT and ET including an interlocking relay IR having a winding ETR associated With the section ET and a winding WTR associated with the section WT. The interlocking relay IR may be of any suitable type such as that shown and described in United States Patent No. 1,799,629, granted to William K. Lockhart and Thomas I. OMeara on April 7, 1931, for Interlocking Relay. Relay IR includes the windings ETR and WTR controlling separate armatures interconnected by an interlocking mechanism. Each of the armatures has a set of contacts associated with it. The interlocking mechanism is so arranged that when both windings are energized, if one of the windings becomes deenergized the armature controlled thereby will release sulficiently to open its associated front contacts and close its associated back contacts. When a winding thus becomes dcenergized while the other Winding is still energized,

the interlocking mechanism is actuated in such manner that if the other Winding subsequently becomes deenergized the armature controlled by such other Winding will not release suificiently far to open its associated front contacts and close its associated back contacts. Furthermore, once the interlocking mechanism has been operated by the deenergization of a winding, the back contacts controlled by the armature last to be released cannot become closed upon the reenergization of the winding first to become deenergized, but the armature will remain in its interlocked position until the winding last to become deenergized is reenergized. The winding ETR is connected across the rails of the section ET over a front contact 11 of the track relay XTR of the short section XT, and the winding WT R is connected across the rails of the section WT over a from contact 10 of the relay XTR. It follows that for a westbound train the winding ETR is deenergized and its armature released to its full down position as the train approaches the intersection and remains in this position until the rear of the train vacates the section XT, and the armature of the Winding WTR is held by the interlocking feature of the relay as the westbound train recedes from the intersection through the track section WT. Similarly, for an eastbound train, the winding WTR is deenergized and its armature is released to its full down position and remains in that position until the eastbound train clears the section XT, and the armature of the winding ETR is held by the interlocking feature of the relay IR as the eastbound train recedes through the section ET.

It is to be pointed out that any one of the other well known arrangements for directional control of the track circuits at a highway crossing may be employed in place of the interlocking relay directional control shown in Fig. I. It is also to be pointed out that each of the windings WTR and ETR with its associated armature constitute a relatively quick acting relay that is responsive to occupancy of the associated track section.

The highway crossing gates G1 and G2 are shown conventionally for the sake of simplicity since these gates may have anyone of several known structures. It is sufiicient for the present application to point out that the gates G1 and G2 are provided with gate arms 12 and 13, respectively, and each of which arms is moved between a lowered position where the arm extends hori- S t it zont' ally across at least a portion of thehighway tri obstruct highwaytraffic and a raised position where the arm extends substantially vertical and does not obstruct highway traflic. Each gate is provided with an operating mechanism, the mechanism for the two gates G1 and G2 being preferably alike. Consequently the mechanism and the control thereof for the G1 only is disclosed in Fig. l for the sake of simplicity because the mechanism and control for the gate G2 would be a duplication thereof.

The mechanism for the gate G1 is indicated as a whole by a dot and dash rectangle 9, this mechanism being operatively connected with the gate arm 12 by a suitable drive mechanism indicated in the drawing by a dotted line 14. The gate mechanism 9 includes a motor M1, a slot magnet SM and a circuit controller Cll, all of which are operatively associated and connected to the gate arm 12. Furthermore, two control relays SN and DN adaptable of being mounted in the housing of the gate mechanism are provided, these relays being referred to hereinafter.

The motor M1 is a direct current reversible motor having an armature i and a field winding is. The motor Ml when supplied with current which flows in its armature 15 in a given direction with respect to the flow of current in field winding 16, is operated as required to raise the arm 12 through the drive mechanism against the usual biasing force, the gate mechanism being counter balanced by weights for the arm 12 to be gravity biased to its lowered position. When the motor Mil is supplied with current which flows in its armature 1.5 in a direction reverse to said given direction, the motor is operated to drive the gate arm toward its lowered position aiding the bias force.

in the following description, the position of the gate mechanism corresponding to the lowered position of the arm will be at times referred to as a zero degree position and the position of the mechanism corresponding to the raised position of the arm will be referred to at times as a 90 degree position. It will be understood, however, that my invention is not limited to a mechanism having a 90 degree movement and a greater or lesser movement may be used. Furthermore, it is to be understood that preferably the mechanism is arranged so that it has a slightly greater than 90 degree movement in order to permit adjustment.

The slot magnet SM includes a draw up winding 17, a holding winding 18 and an armature 19. Preferably, the slot magnet is of the well known construction, wherein the armature 19 carries a pawl which. engages a ratchet gear operatively attached to a suitable element of the drive mechanism, and the armature 19 when picked up causes the pawl to engage the ratchet gear and prevent movement of the arm toward its lowered position. When the armature 19 is released the mechanism is unlatched and free to move in either direction. The arrangement is such that the armature 19 is picked up to its latching position only when both windings 1'7 and 18 are energized but once picked up the armature is held in its latching position by the energizing of the holding winding 13 alone.

The controller C1 includes a series of circuit controlling contacts identified in Fig. 1 by the numerals O to 8, inclusive. These contacts are operated by the mechanism between a first extreme position corresponding to the (l degree position and a second extreme position corresponding to the 90 degree position of the gate mechanism. in Fig. 1, these control contacts are shown conventionally and the portion of the movement in degrees between the two extreme positions at which each specific contact is closed is set forth in the chart of Fig. 3. It should be noted that the contact i of the controller is closed from 0 to 89 degrees in one direction of movement of the mechanism and from 83 to 0 degrees in the other direction of movement. The means by which this controller contact is opened at the two different positions in the movement of the gate arm is asaaisse' preferably that "disclosed and claimed in Letters Patent of the United States No. 2,363,936, granted November 28, 1944, to Herbert L. Bone, for Circuit Controllers, and the construction and function for such a contact are fully set forth in that patent.

The two relays SN and Di t are standard direct current relays which are provided with heavy current carrying contacts for control of the motor operating circuits.

The signals Sit and S2 are indicated conventionally in l as flashing light signals by the symbol commonly u to indicate a dashing light type signal, and only the circuits for the signal S1, which is operatively associated with the gate G1 are shown in detail since the signal S2 which is operatively associated with the gate G2 would be a duplication of signal S1. The signal S3 is an audible signal, such as an electric bell.

The control apparatus for the gate G11 and the signals Si and S3 as disclosed in Fig. 1 includes in addi-.

tion to the traclt circuits described hereinbefore, a group of control relays comprising a slow releasing relay TPR, two repeater relays TPA and TPCR, a stick relay XSR and a signal control relay XGR, together with a flasher relay EOR. As shown, these control are of the direct current type but other types relays can he used. As shown relay TFR is provided with resistor in a capacitor 23 which are connected series across the winding of the relay to provide the re 1y i a slow release characteristic, the parts being proportioned so that the relay TPR has a slow release period of the order of, say, 5 seconds, but other slow release periods can be used. The remaining relays of the group are direct current neutral relays of the usual acting typ except relay EOR which is a standard form of a ll... er relay well known to the art.

It is to be noted that since direct current is used for operating the gate mechanism and also for energizing the control relays, the apparatus is proyied with a source of direct current such as a battery, not shown, the positive and negative terminals of this source of direct current being indicated by the reference characters B and N, respectively. Preferably, a source of alternating current, the terminals of which are indicated at BE and EN, is also provided for supplying energy for the signals 51 and S2.

The apparatus of Fig. l is shown in the position it occupies under normal conditions, that is, when no train occupies the section ET, X1 or WT and the track relay XTR and the interlocking relay are energized.

Under this normal condition of the apparatus, the slow release relay TPR is energized by a circuit extending from terminal B of the current source through front contacts 22 and 23 of the windings WTR and ETR, respectively, and winding of relay to terminal N of the current source. Thus this relay is normally energized and is deenergized in response to occupancy of any one of the track sections, but the relay does not release its armature for a predetermined slow release period, here assumed as 5 seconds for illustration. In other words, the relay TPR is a slow release relay responsive to occupancy of the track sections.

The repeater relay T PCR is provided with a simple circuit including front contact 2d of relay TPP. and thus this relay TPCR does not release until the end of the selected slow release period for re ay TPR when train enters an approach traclt section. The repeater relay TPA is provided with alternate energizing circuits, one of which includes terminal B, front contacts and 12.6 of the wind ings WTR and ETR, respectively, front contact of re lay T PR, winding of relay This and terminal N; and the other of which circuits extends from terminal B through controller contact 1 closed at the 86 to 93 degree position of the gate mechanism, front contact 27 of relay TPR and winding of relay TPA to terminal N.

Thus the relay TBA responds quickly to tramc conditions .of the track. se ons l except when the gate is at its vertical position and controller contact 1 is closed.

Under normal conditions, the signal control relay XGR is energized by current flowing from terminal B through front contacts 30 and 31 in multiple of relay TPA, wires 32 and 33, controller contact 2 closed at the 86 to 93 degree position of the mechanism, winding of relay XGR and front contacts 34 and 35 in series of the interlocking relay to terminal N. Also, under normal conditions, the holding winding 18 of the slot magnet SM is energized by a simple circuit including front contact 2'9 of the slow release relay TPR. Thus with the gate mechanism raised to its vertical position in a manner to appear later it is held in this vertical position under normal conditions.

In view of the foregoing description for this group of control relays, it is to be seen that the interlocking relay IR and the relay XGR are released relatively quick when a train enters an approach track section, but that the relays TPR and TPCR are released only after a selected time delay period when a train enters an approach section. Also, the relay TPA is released after the delay period with the gate at its vertical position when a train enters an approach section but is released relatively quick when the gate is at some intermediate posiiton and a train enters an approach section.

I shall next assume that a westbound train approaches the crossing to enter the approach section ET and then advances to pass over the crossing and recede from the crossing through the section WT. When the train enters the section ET the winding ETR is shunted and its armature is at once released to its full down position where the front contacts 23, 26 and 34 are open and the full down contacts 23 and 26 are closed. The opening of front contact 23 deenergizes the slow acting relay TPR but that relay does not release until the end of its slow release period of 5 seconds and thus the holding Winding 18 of the slot magnet SM is retained energized for this delay period. The opening of front contact 34 of winding ETR causes the relay XGB. to be deenergized and immediately released closing back contacts 37 and 38. The closing of back contact 37 completes the operating circuit for the flasher relay EOR and that relay is operated to alternately close its two contacts 39 and 46). The closing of back contact 33 of relay XGR prepares a circuit for supplying energy to the signal S1 so that with the flasher relay EOR operated energy is applied alternately to the two lamps of each of the two pairs of lamps 41 and 42, and 43 and 44, provided for the signal S1 and the lamps of each pair are alternately flashed as a warning signal to highway users. With the armature of a flasher relay EDR in the position shown in Fig. l, lamps 41 and 43 will be energized by a circuit which may be traced from terminal EB of the alternating current source, over back contact 38 of relay XGR, lamps 41 and 43 in multiple, and contact 40 of relay EOR to the negative terminal EN of the alternating current source. At this time, lamps 42 and .4 are effectively short circuited by contact 4-0 of relay EOR and, accordingly, they Will be dark. When the armature of relay EOR moves to its reverse position, thereby opening contact 40 and closing contact 39, lamps 42 and 44 will become energized by a circuit which may be traced from terminal EB of the alternating current source, over back contact 38 of relay XGR, contact 33 of relay EOR, and the lamps 42 and 4-6, in multiple, to the negative terminal EN of the alternating current source. At this time, lamps 41 and 43 will be short circuited by contact 39 of relay EOR and will be dark. Also, the closing of back contact completes a circuit for energizing the lamp 25 and that lamp is steadily illuminated. Preferably, one pair of the flashing lamps of signal S1 and the lamp 45 would be mounted on the gate arm 12. Furthermore, the closing of back contact 23 of the winding ETR of the interlocking relay completes a circuit for energizing the signal bell 53, current flowing from terminal B through front contact 22 for the winding WTR,

hack contact 23 for the winding ETR, winding of the bell S3, wire 46 and controller contact 6 closed at the 10 to 93 degree position of the mechanism to terminal N. Thus the bell is sounded as an additional warning signal of the ap proach of the train. It follows that the warning signals S1 and S3 are at once set into operation but the gate arm does not move from its vertical position during the 5 seconds delay period. When the relay TPR is released opening front contact 29, the holding winding 18 is deenergized and the gate mechanism is unlatched and starts to move to ward its lowered position under the influence of its bias. The opening of front contact 24 of relay TPR causes the repeater relay TPCR to be deenergized and released. Also, the opening of front contact 27 of relay TPR opens both circuits for the repeater relay TPA and that relay is deenergized and released. Thus the relays TPR, TPCR and TPA respond to the train entering the track section ET only after the delay period. At this time there is completed an operating circuit for the motor M1, current flowing from terminal B through back contacts 30 and 31 in multiple of relay TPA, back contacts 47 and 48 in multiple of relay TPCR, wire 49, controller contact 0 closed at the 93 to 46 degree position, wire 50, and winding of relay DN to terminal N, and then with relay DN picked up, current flowing through the front contact 51 of relay DN, wire 52, armature 15 of the motor from right to left, wire 53, front contact 54 of relay DN, and field winding 16 of the motor to terminal N. With the motor M1 thus supplied with current, it is operated in the direction required for the motor to drive the gate mechanism toward its lowered position aiding the bias force of the gate. When the gate arm has reached the 46 degree position, the controller contact 0 is opened and energy for operating the motor is discontinued but the gate mechanism continues in its downward movement due to the force of the bias. Subsequent to the deenergizing of relay DN and the motor, the motor is provided with a snubbing circuit for dynamic braking and which snubbing circuit can be traced from the right-hand terminal of armature 15 through wire 52, back contact 51 of relay DN, field winding 16, terminal N and thence through resistor 55, back contact 56 of relay SN, back contact 54 of relay DN and wire 53 to the left-hand terminal of the motor armature 15. When the gate mechanism nears its lowered position, the controller contact 5 is closed at the 18 degree position and the snubbing circuit of the motor is completed from terminal N through controller contact 5 and back contacts 56 and 54 of relay SN and DN, respectively, and the motor is substantially short circuited to provide heavy dynamic raking as the gate arm nears its full down position. The section TE is made of such a length that the delay period of 5 seconds and the time required for gate G1 to move to its lowered position are consumed before the head end of the train reaches the crossing when the train is traveling at the maximum permissible speed.

It is to be noted that when the gate reaches the 10 degree position, the circuit for the bell S3 is opened at controller contact 6 and the bell becomes silent. Thus as the train passes over the intersection the flashing light signal S1 and the lamp 45 are illuminated as warning signals and the arm 12 of the gate G1 extends across the highway as a barrier to highway traflic.

It is also to be pointed out that in this downward operation of the gate of Fig. 1, the motor M1 is not energized to drive the gate down until after a slight delay subsequent to the deenergizing of the slot magnet and there is time for the usual pawl of the slot magnet to become fully disengaged from the ratchet gear. This slight delay is provided by the time required for relay TPA to release and transfer from its front to its back contacts plus the pickup time for the relay DN. This arrangement of the control relays and circuits is desirable because if the motor is energized before the slot magnet has had time to release the slot pawl there is undue Wear and strain between the pawl and the ratchet gear.

When the rear end of the train vacates the section XT,

essence the relay XTR and in turn the winding ETR of the interlocking relay are reenergized. The winding WTR of the interlocking relay is deenergized as the train enters the section WT in receding from the crossing but the armature of winding WTR is held by the interlocking feature of the relay 1R so that the contacts of the winding WTR are not actuated. The energizing of the winding ETR and the picking up of its armature to open back contact 23 opens the bell circuit at a second point and the closing of front contact 34 closes the circuit for the signal control relay XGR at one point but this circuit is now held open at the controller contact 2 with the result the flashing light signal S1 and the lamp 45 are still illuminated as a warning signal until the gate arm reaches the 86 degree position. The closing of front contact 23 of the interlocking relay completes the circuit for the relay TPR and that relay is picked up with the result the repeater relays TPCR and TPA are both reenergized and picked up. At this time another operating circuit is formed for the motor and which operating circuit extends from terminal B through front contacts Eli and 31 in multiple of relay TPA, wire 322, controller contact 4 closed for the to 89 degree position, wire 5'7, winding of relay SN to terminal N, and then with relay SN picked up, the motor circuit is extended over front contact 56 of relay SN, back contact 54 of relay DN, wire 53, motor armature 15 from left to right, wire 2, back contact 51 of relay DN and motor field winding 16 to terminal N. The motor M1 is now energized and operated as required to drive the gate from its lowered to is raised position.

1 shall next assume that before the gate arm has reached its full raised position and is at some intermediate point in this movement, such as, for example, the 60 degree position, a second westbound train enters the section ET and shunts the winding ETR causing the armature of that winding to be again released. It is to be observed that when relay TPR was reenergized subsequent to the first train clearing the crossing, the holding winding 18 of the slot magnet SM was reenergized but the armature 19 of the slot magnet was not picked up because the energizing of winding 18 alone is insufficient to pick up the armature 1?. Also, when the gate was lowered, the stick relay XSR was provided with a pickup circuit that includes the controller contact 7 closed at the 0 to degree position of the gate. Then the stick relay XSR is retained energized by a stick circuit including its own front contact 36 and controller contact 8 closed at the 6 to 86 degree position of the mechanism while the gate arm is being raised. Hence, when the second train enters the section ET, the closing of back contact 26 of winding ETR of the interlocking relay completes a circuit for the draw up winding 17 of the slot magnet, the circuit extending from terminal B through front contact 25 and back contact 26 of the interlocking relay, front contact 53 of relay TPCR, front contact 59 of the stick relay XSR and winding 17 to terminal N. With both of the windings 17 and 1a of the slot magnet energized the armature 19 is drawn up to its latching position to hold the gate mechanism at this intermediate position. Furthermore, it is to be noted that the opening of front contact 26 of the winding ETR of the interlocking relay causes the repeater relay TPA to be at once deenergized and released to open the motor operating circuit and operation of the motor is discontinued. It follows that the raising of the gate G1 is stopped at this intermediate position and it is held at that position during the delay period provided for the slow acting relay TPR. However, when the winding ET R of the interlocking relay was shunted and its armature released due to the second train entering section ET, the closing of the back contact 23 recloses the circuit for the bell S3 and the bell is set into operation as a warning that the gate is to be lowered from an intermediate position. At the end of the selected delay period of 5 seconds provided for relay TPR, this relay is released and the gate is unlatched due to the deenergizing of the slot magnet windings 18 and 17 and the gate is moved toward its lowered position in the usual manner explained for the first train. It is clear that the time consumed in holding the gate at an intermediate position for the usual delay period and then operating the gate from this intermediate position to its full lowered positionis something less than the delay period plus the time required to operate the gate from the full vertical position to its lowered position as provided for the first train, and hence the normal length of the section ET is sufficient to assure that the gate mechanism is lowered from an intermediate position to its down position prior to the second train reaching the intersection. Also a warning signal S3 is provided for the usual delay period that the gate is to be lowered and the possibility of lowering the gate in front of or on top of a highway vehicle without a proper warning is minimized.

Assuming next that a second train does not enter the section ET when the gate is being raised, and the operation of raising the gate is continued uninterrupted subsequent to the first train clearing the section XT. Under this condition the stick circuit for the relay XSR is opened at controller contact 8 at the 86 degree position and the relay XSR is at once released. The closing of back contact 59 of the relay XSR completes a circuit from the draw up winding 17 of the slot magnet, current flowing from terminal B through front contacts 30 and 31 in multiple of relay TPA, wire 32, controller contact 4, controller contact 3 closed at the 86 to 93 degree position of the mechanism, back contact 59 of relay XSR and winding 17 to terminal N. Thus the armature 19 of the slot magnet is drawn up to the latching position and the gate latched as the gate nears its raised position due to the energizing of the windings 17 and 13. When the motor operating circuit and the energizing circuit of the draw up winding 1'7 are opened at controller contact 4 at the 89 degree position or substantially at the raised position of the gate, the gate is held latched due to the energizing of holding winding 18.

It follows that when no second train enters the approach section ET while the gate is being raised the slot magnet SM is effectively energized to latch the mechanism by a normal circuit means which includes the path over front contact 29 of the slow release relay TPR for winding 18, and the path over back contact 59 of relay XSR, controller contacts 3 and 4 and from contact 30 of relay TPA for the winding 17. When a second train enters the section ET while the gate is being raised the slot magnet SM is effectively energized to latch the mechanism by an auxiliary circuit means which includes the path over front contact 29 of relay TPR for winding 18, and the path over front contact 59 of relay XSR, front contact 53 of relay TPCR and back contact 26 of the interlocking relayIR for winding 17.

Operation of the gate G1 for an eastbound train is similar to that described for the westbound train and the operation of the apparatus for an eastbound train will be apparent from an inspection of Fig. 1 taken in connection with the foregoing description of the operation of the apparatus for a westbound train.

In Fig. 2, the track layout, the track circuits and the highway crossing gates and signals provided at the highway crossing are the same as in Fig. 1. Also, the gate mechanism is of the same type as shown in Fig. 1. In Fig. 2 thecontrol apparatus includes a group of relays in addition to the track circuits and which group of relays comprises a slow release relay TPR, a repeater relay TPA, a signal control relay XGR and a relay XR in addition to the flasher relay EOR. The slow release relay TPR is provided with a slow release period by the connection of a resistor and a condenser in series across thewinding the same as in Fig. 1 and it is here assumed that the slow release period for the relay TPR of Fig. 2

1 l is of the order of 5 seconds the same as in Fig. 1. The relays XR, XGR and TPA are direct current neutral relays of the usual type.

Under normal conditions of Fig. 2, that is, when the track sections are unoccupied and the interlocking relay IR and track relay XTR are picked up, the slow release relay TPR is energized by a circuit including the front contacts 22 and 23 of the interlocking relay the same as in Fig. 1. With the relay TPR picked up closing front contact 6th, the repeater relay TPA is energized and picked up. Also, the closing of front contact 29 of relay TPR completes a circuit for the holding winding 18 of the slot magnet and the gate is latched at its raised position, assuming that the gate mechanism has been operated to the raised position in a manner to appear hereinafter. Under this normal condition the relay XR is provided with a simple energizing circuit including front contacts 61 and 62 of the interlocking relay. Also the signal control relay XGR is supplied with current from battery 8 through front contacts 34 and 31 in multiple of relay TPA, wire 32, controller contact 2 closed at the 86 to 93 degree position of the mechanism, front contact 63 of relay XR and winding of relay XGR to terminal N. Thus, under the normal condition of the apparatus of Fig. 2, the gate is latched at the raised position and the warning signals are inactive.

In describing the operation of the apparatus of Fig. 2, I shall assume that a westbound train approaches the crossing and enters the section ET shunting the winding ETR of the interlocking relay. The opening of front contact 23 of the winding ETR opens the circuit for the slow release relay TPR but that relay remains picked up for its delay period of 5 seconds and the gate is retained latched at its raised position. The opening of front contact 62 of winding ETR of the interlocking relay causes the relay XR to be deenergized and in turn the relay XGR to be deenergized and released. The closing of back contact 3'7 of the relay XGR completes the circuit for the flasher relay EOR and that relay is operated to alternately close its contacts 39 and 46), so that the lamps of the signal 31 are supplied with current alternately due to the closing of back contact 38 of the relay XGR and the operation of the flasher relay. That is to say, the lamps of each pair of lamps for the signal S1 are alternately flashed due to the operation of the flasher relay, and the lamp 45 is steadily illuminated due to the closing of back contact 38 of relay XGR. This operation of the signal S1 and the lamp 45 is the same as that provided by the apparatus of Fig. 1. The closing of the full down contact 23 of the winding ETR of the interlocking relay completes the circuit for the bell S3 and it is sounded, the bell receiving current through the controller contact 6 which is closed at the 10 to 93 degree position of the mechanism, the same as in Fig. 1.

When the relay TPR of Fig. 2 is released at the end of the delay period of 5 seconds, the opening of front contact 29 deenergizes the holding winding 18 of the slot magnet and its armature 19 is released to unlatch the gate mechanism and permit the mechanism to move toward the lowered position due to the bias force. Also, the opening of front contact 60 of relay TPR causes the repeater relay TPA to be released to close its multiple back contacts 39 and 31 and complete a motor operating circuit, current flowing from terminal l3 over back contacts and 31 in multiple, wire 64, controller contact 0 closed at the 93 to 46 degree position, and Winding of relay DN to terminal N, and thence when relay DN is picked up current flowing through front contact 51 of relay DN, wire 52, motor armature 15 from right to left, wire 53, front contact 54 of relay DN and motor field winding 2.6 to terminal N. This energizing of the motor M1 is of the polarity that the motor is operated to drive the gate mechanism toward its lowered position aiding the bias force. At the 46 degree position the controller contact 0 is opened and the relay DN and in turn the motor Ml are deenergized, but the gate continues its movement toward its lowered position due to the bias. The closing of back contacts 51 and 54 of relay DN completes the snubbing circuit for the motor through resistor 55 and back contact 56 of relay SN, the same as explained for Fig. 1. Also, at the 10 degree position of the gate, the closing of controller contact 5 shunts the resistor 55 and the motor M1 is substantially short circuited to provide heavy dynamic braking as the gate nears the 0 degree position. The opening of controller contact 6 at the 10 degree position deenergizes the bell S3 and it becomes silent. Thus, as the train passes over the crossing the flashing light signal Si. and the lamp 45 are illuminated as warning signals and the gate arm is at the lowered position to obstruct highway traffic.

When the train has moved west and the rear of the train has vacated section XT, the track relay XTR and in turn the winding ETR of the interlocking relay are reenergized and picked up, the armature of winding WTR of the interlocking relay being held by the interlocking feature of the relay as the train recedes through the section WT. The opening of back contact 23 opens the bell circuit at a second point and the closing of front contact 23 causes the relay TPR to be reenergized and picked up and in turn the repeater relay TFA to be energized and picked up. Furthermore, the closing of front contact 62 of the interlocking relay completes a circuit for relay XR and that relay is picked up. However, at this time the circuit for the relay XGR is held open at controller contact 2 and the visual signal S1 and lamp 45 are still illuminated while the gate is being raised.

With the closing of front contacts 3'9 and 31 of relay TPA, a motor operating circuit is completed and current flows from terminal B over front contacts 30 and 31' in multiple, wire 32, controller contact 4, wire 65, front contact 6-6 of relay XR, wire 6'7, and winding -c nielay SN to terminal N of the current source, and

the'n'with relay SN picked up, current flows from wire 67 through front contact 56 of relay SN, back contact 54 of relay DN, wire 53, motor armature 15 from left to right, wire 52, back contact 51 of relay DN ar d field winding 16 of the motor to terminal N. The motor M1 is now operated in the direction required to raise the gate from its lowered position.

I shall assume that when the gate is being raised and has reached an intermediate point of, say, 6;) degrees, a second westbound train enters the section ET and shunts the Winding ETR causing its armature to he released. The closing of the full down contact 23 of the interlocking relay completes the bell circuit and hell at once sounded as a warning that the gate is about to be lowered. The opening of the front contact s2 of the winding ETR causes the relay XR to be at once released opening front contact 66 which is included in the motor operating circuit with the result the operation of the motor is discontinued and the raising of the gate stopped. The closing of back contact 66 of relay completes a circuit for the draw up winding 17 of the slot magnet, the circuit extending from terminal B through front contacts 30 and 31 in multiple of relay T PA, wire 32, controller contact 4, wire 65, back contact as of relay X wire 68 and winding 17 to terminal N. Since the holding winding 18 of the slot magnet is also energized at this time due to the closing of front contact 29 of the relay TPR, the armature 19 of the slot magnet is drawn up and the gate mechanism latched at this intermediate position.

At the end of the delay period for the release of relay TPR, the opening of front contacts 2) and 6d of that relay deenergizes the holding winding 13 of the slot magnet and also denergizes the repeater relay TPA which releases and opens the circuit for the draw up winding 17 The deenergizing of the slot magnet permits the gate naatresa 13 V mechanism to be unlatched and it starts movement toward its lowered position due to the bias force. The release of relay TPA closing back contacts 30 and 31 completes the operating circuit for the motor to drive the gate down to the 46 degree position where the motor operating circuit is opened at the controller contact 0, it being noted that this motor operating circuit includes back contacts 30 and 31 in multiple, wire 64, controller contact 0, wire Stl, winding of relay DN to terminal N and then with relay DN picked up the circuit is extended through front contact 51, wire motor armature 15 from right to left, wire 53, front contact 54- and field winding 16 to terminal N. it follows that in response to the second train entering the section ET, the bell S3 is at once sounded as an additional warning signal and the gate is stopped and held stationary at the point to which it has been raised and then at the end of the delay period, the gate is operated to its lowered position in the usual manner. Thus, when this second train reaches the crossing and passes over the intersection, the warning signals are operated and the gate arm is down extending across the highway, it being noted however, that the bell S3 becomes silent at the degree position of the gate mechanism.

Assuming, however, that a second train does not enter section ET when the gate mechanism is being raised, it is clear that the operation of raising the gate is continued to the vertical position and there the motor circuit is opened and the slot magnet armature drawn to the latching position to hold the gate up in the raised position in the same manner as described in connection with the apparatus of Fig. 1. Furthermore, it is clear that the operation of the apparatus of Fig. 2 for an eastbound train is substantially the same as that described above for a Westbound train, and this operation of the apparatus for an eastbound train will be apparent from an inspection of Fig. 2 taken in connection with the description of the operation of the apparatus for a westbound train.

It follows that in Fig. 2, when no second train enters the approach section ET while the gate is being raised the slot magnet SM is efiectively energized to latch the mechanism by the normal circuit means including the path over front contact 29 of relay TPR for winding 18 and the path over controller contacts 3 and 4 and front contact 30 of relay TPA for winding 17. When a second train enters the section ET while the gate is being raised the slot magnet is ei'fectively energized to latch the rnechanisrn by an auxiliary circuit means including the path over front contact 29 of relay TPR for winding 18 and the path over back contact 66 of relay XR, controller contact 4 and front contact 30 of repeater relay TPA for winding 17.

Apparatus such as here disclosed and described has the advantages that when a second train enters an approach section to a highway crossing when the gate mechanism is being raised, the mechanism is held stationary at the intermediate point to which it had been raised for the usual delay period and a signal not previously operated during the raising of the gate is set into operation as a warning signal that the gate is about to be lowered and then at the end of the delay period the gate is brought to its lowered position in the usual manner. Hence the lowering of the gate immediately in front of or on top of motor vehicles is avoided, and no increase in the length of the approach sections is required.

Although I have herein shown and described but two forms of control apparatus for highway crossing gates and signals embodying my invention it is to be understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination with a highway crossing gate mechanism having an arm operable to a substantially horizontal position and provided with an electric motor adapted when energized to raise the arm to a substantially vertical position, said mechanism being provided with a multiple contact circuit controller actuated by the mechanism and with a slot magnet adapted when elfectively energized to latch the mechanism against movement of the arm toward the horizontal position, control apparatus for holding the mechanism with the arm at any intermediate point between the horizontal and the vertical positions for a selected time interval and then allowing the arm to be moved, toward the horizontal position, comprising, circuit means having a first and second condition, a quick acting relay actuated by said circuit means to an energized or deenergized condition in accordance with the condition of said circuit means, a slow release control relay actuated to an energized or deenergized condition in accordance with the condition of said circuit means and having a slow release period equal to a selected time interval, control means for said motor comprising a contact closed in the energized condition of said quick acting relay and a contact of the controller of the gate mechanism closed except at the vertical position of the gate arm connected to the motor of the gate mechanism to energize the motor, a normal slot magnet circuit means including a front contact of said slow release control relay and a contact of the controller closed just prior to the vertical position of the gate arm connected to the slot magnet of the gate mechanism to elfectively energize said slot magnet; and an auxiliary slot magnet circuit means including a front contact of said slow release relay, a contact closed only when said quick acting relay is released, and a contact of said controller closed during a selected portion of the movement of the gate mechanism toward its vertical position connected to said slot magnet to effectively energize the slot magnetv 2'. in combination with a highway crossing gate mechanism having an arm operable to a substantially horizontal position and provided with an electric motor adapted when energized to raise the arm to a substantially vertical position, said mechanism being provided with a multiple contact circuit controller actuated by the mechanism and with a slot magnet adapted when effectively energized to latch the mechanism against move ment of the arm toward the horizontal position, control apparatus for holding the mechanism with the arm at any intermediate point between the horizontal and the vertical positions for a selected time interval and then allowing the arm to be moved toward the horizontal position, comprising, circuit means having a first and second condition, a quick acting relay and a slow acting relay actuated to energized or deenergized conditions in accordance with the condition of said circuit means, said slow release relay having a slow release period equal to a selected time interval, control means for said motor comprising a contact closed in the energized condition of said quick acting relay and a contact of the controller of the gate mechanism closed except at the vertical position of the gate arm connected to the motor of the gate mechanism to energize the motor, and slot magnet circuit means including a back contact controlled by said quick acting relay, a front contact of said slow release relay and a contact of said controller closed during a selected portion of the movement of the gate mechanism connected to said slot magnet to effectively energize the slot magnet.

3. In combination with a highway crossing gate mechanism having an arm operable to a substantially horizontal position and provided with an electric motor adapted when energized to raise the arm to a substantially vertical position, said mechanism being provided with a multiple contact circuit controller actuated by the mechanism and with a slot magnet having a draw up winding and a holding winding, said slot magnet being operable 1b to latch the mechanism against movement of the gate arm toward the horizontal position when both windings are energized, control apparatus for holding the arm of a gate mechanism located at a crossing of a highway and a railway against immediate movement of the arm toward the horizontal position when a train approaches within given limits of the crossing while the gate arm is being driven toward its vertical position, comprising, a slow release relay having a selected slow release period, a quick acting relay, means responsive to traffic approaching the crossing within said given limits and having connections to said relays to energize both relays when no train is approaching the crossing within said limits and to deenergize both relays when a train enters said given limits, a motor circuit means controlled by a front contact of said quick acting relay and including a contact of the controller of said gate mechanism closed except when the arm is in the vertical position to energize the motor of the gate mechanism, and a slot magnet circuit means having two paths one of which includes the holding winding of the slot magnet of said mechanism and a front contact of said slow release relay and the other of which paths includes the draw up winding of the slot magnet, 21 back contact controlled by the quick acting relay, a contact closed only when said slow release relay is picked up and a contact closed during a selected portion of the movement of the gate arm.

4. In control apparatus for a highway crossing gate mechanism having an arm biased to an obstructing position and provided with an electric motor connected to said mechanism and operable when energized to drive the arm to a nonobstructing position, said mechanism including a circuit controller actuated by the mechanism and a slot magnet having a draw up and a holding winding, said slot magnet having an armature which is drawn up to latch the mechanism against movement toward the obstructing position only when both of its windings are energized but which armature is retained in its latching position by the energizing of the holding winding only, the combination comprising, a track circuited section formed in the approach of a railway to a highway crossing at which a crossing gate is located, a slow rel-ease relay made responsive to occupancy of said section and provided with a selected slow release period, a quick acting relay made responsive to occupancy of said section, a motor circuit including a contact closed only when the quick acting relay is picked up and a contact of the controller of the gate mechanism at said highway crossing closed except at the nonobstructing position to energize the motor of the gate mechanism, a circuit connected to the holding winding of the slot magnet of the gate mechanism to energize that winding and including a front contact of said slow release relay, a normal circuit connected to the draw up winding of the slot magnet to energize that winding and including a contact of said controller closed only just prior to the nono'ostructing position of the gate arm, and an auxiliary circuit means connected to said draw up winding to energize that winding and including a contact closed only when said quick acting relay is released, a contact closed only when said slow release relay is picked up and a contact of said controller closed during a selected portion of the movement of the gate arm from its obstructing to its nonobstructing position.

5. in control apparatus for a highway crossing gate mechanism having an arm operable to a horizontal position and provided with an electric motor ada, ted when energized to drive the gate arm to a vertical position, said mechanism having a multiple contact controller actuated by the mechanism and having a slot magnet including a draw up and a holding winding, the combination comprising, a railway track having a highway crossing at which a gate mechanism is located, a track section having a track circuit formed in said track in the approach to crossing, a first control relay controlled by said track circuit and energized when the section is unoccupied and deenergized when the section is occupied, said first relay having a selected slow release period, a second control relay controlled by said track circuit and energized when the section is unoccupied and deenergized when the section is occupied, said second relay having a relatively quick release, a circuit including a front contact of said first relay to energize a holding winding of the slot magnet of said gate mechanism, circuit means including a front contact of said second relay and a contact of the controller of said gate mechanism closed except at the vertical position to energize a motor of the gate mechanism, a normal circuit means for energizing a draw up winding of the slot magnet of said gate mechanism and including a contact of said controller closed only just prior to the vertical position, and another circuit means for energizing said draw up winding and including a back contact of said second relay and a contact of said controller closed at a selected movement of the mechanism and opened at the vertical position.

6. In control apparatus for a highway crossing gate mechanism biased for movement to an obstructing position and provided with an electric motor adapted when energized to drive the mechanism toward a nonobstructing position, said mechanism including a multiple contact controller actuated by movement of the mechanism and a slot magnet adapted when effectively energized to latch the mechanism against its bias movement, the combination comprising, a railway having a highway crossing at which a gate mechanism is located, track circuit means formed in the track of the railway in the approach to the crossing and responsive to trains approaching the crossing, a relay having a selected slow release period and having connection to said track circuit means to be energized when no train approaches the crossing and to be deenergized when a train approaches the crossing, a quick acting relay having connections to said track circuit means to be energized when no train approaches the crossing and to be deenergized when a train approaches the crossing, circuit means including a front contact of said quick acting relay and a contact of the controller of the gate mechanism at said crossing closed except at' the nonobstructing position connected to the motor of the gate mechanism to energize the motor, a normal circuit means including a front contact of said slow release relay and a contact of the controller closed for a selected movement of the mechanism just prior to the nonobstructing. position connected to the slot magnet of the mechanism to efiectively energize the magnet, and an auxiliary circuit means including a back contact of said quick acting relay and a contact of the controller closed during the movement of the mechanism from the 0bstructing position to just prior to reaching the nonobstructing position connected to said slot magnet to effectively energize the magnet.

7. In combination with a highway crossing gate'mechanism operable to a horizontal position and provided with an electric motor adapted when energized to drive the gate to a vertical position and with a multiple contact controller actuated by movement of said mechanism and With a slot magnet having a draw up and a holding winding, control apparatus for holding the gate mechanism at a position intermediate the horizontal and vertical positions comprising in combination, a first control relay having a selected slow release period, a quick' acting second control relay, a circuit including a front contact of said first relay connected to said holding winding to energize that winding, a circuit means including a front contact of said second relay and a contact of said controller closed except at the vertical position connected to said motor to energize the motor, a

normal circuit means including a contact of said con-v troller closed for a selected movement of the mechanism just prior to the vertical position connected to said draw 'up winding to energize that winding, an auxiliary cir- 17 cuit means including a back contact of said second relay and a contact of said controller closed for a selected movement of the mechanism and opened at the vertical position connected to said draw up winding to energize that winding, and trafiic responsive means for controlling said first and second control relays.

8. In combination with a highway crossing gate mechanism operable to a horizontal position and provided with an electric motor adapted when energized to drive the gate to a vertical position and with a multiple contact controller actuated by movement of said mechanism and with a slot magnet having "a draw up and a holding winding, control apparatus for'holding the gate mechanism at a position intermediate the horizontal and vertical positions comprising in combination, a first control relay having a selected slow release period, a quick acting second control relay, a circuit including a front contact of said first relay connected to said holding winding to energize that winding, circuit means including a front contact of said second relay and a contact of said controller closed except at the vertical position connected to said motor to energize the motor, a normal circuit means including a contact of said controller closed for a selected movement of the mechanism just prior to the vertical position connected to said draw up winding to energize that winding, an auxiliary circuit means including a back contact of said second relay and a contact of said controller closed for a selected movement of the mechanism and opened at the vertical position connected to said draw up winding to energize that winding, and control circuit means responsive to traffic conditions and having connections to said control relays to govern the energization of the relays in accordance with the presence or absence of railway traffic adjacent said gate.

9. In combination with a highway crossing gate mechanism and highway crossing warning signal, said gate mechanism having an arm operable to a lowered and to a raised position and provided with a motor adapted when energized to drive the arm to the raised position and which mechanism includes a controller actuated by the mechanism and a slot magnet efiective when energized to latch the mechanism against being operated to its lowered position, said signal adapted to provide a distinctive indication when energized, control apparatus for operating the gate arm back to its lowered position from an intermediate point in the movement from the lowered to the raised position, comprising in combination, a gate mechanism and a warning signal located at a highway crossing, a first and a second control relay means, said first control relay means operable to a first position when energized and to a second position after a selected delay period when deenergized, said second control relay means operable to a first position when energized and to a second position relatively quick when deenergized, a motor operating means including a first position contact of said second relay menas and a contact of a controller of said mechanism closed except at the raised position connected to a motor of the mechanism to energize the motor, an auxiliary circuit means including a second position contact of said second control relay means, a first position contact of said first control relay means and contacts of said controller closed except at the raised position connected to a slot magnet of said mechanism to efiectively energize the slot magnet to latch the mechanism, a signal operating circuit including a second position contact of said second control relay means and a contact of said controller closed except at the lowered and at the raised positions connected to said signal to energize the signal, and circuit means responsive to traflic conditions and having connections to said first and second control relay means to govern the energizing and deenergizing thereof.

10. in combination with a highway crossing gate and a highway crossing warning signal located at the intersection of a railway and a highway, said gate including an arm operable to a lowered and to a raised position i and provided with an electric motor adapted when energized to drive the arm to the raised position, said gate having a controller actuated according to the position of the arm and a slot magnet for latching the gate against movement of the arm to the lowered position, said slot magnet having a holding and a draw up winding; control means including track circuits responsive to trains approaching the intersection within set limits, aslow re lease control relay having a selected slow release period, a quick acting control relay, said control relays having connections to said track circuits to energize both relays when no train approaches the intersection within said limits and to deenergize both relays when a train approaches the intersection within said limits, a motor circuit means including a contact closed only when said quick acting control relay is picked up and a contact of the controller of said gate closed except when the gate arm is raised connected to the motor of the gate to'energize the motor, a circuit including a front contact of said slow release relay to energize the holding winding of the slot magnet of said gate, a normal circuit to energize the draw up winding of said slot magnet and including a front contact of said quick acting relayand a contact of said controller closed just prior to the raised position of the gate arm, an auxiliary circuit to energize said draw up winding and including a back contact of said quick acting relay, a contact closed only when said slow release relay is picked up and a contact of said controller closed except at the raised position, and a signal circuit to energize said signal and including a back contact of said quick acting relay and contacts of said controller closed except atthe lowered and at the raised positions. l i

11. In combination with a highway crossing gate mechanism operable to a horizontal position and provided with an electric motor adapted when energized to drive the gate to a vertical position and with a multiple contact controller actuated by movement of said mechanism and with a slot magnet having a draw up and a holding winding, control apparatus for holding the gate mechanism at a position intermediate the horizontal and vertical positions comprising in combination, a first control relay having a selected slow release period, a quick acting second control relay, a repeater relay having alternate energizing circuit paths, one of which includes a front contact of said second control relay and the other of which paths includes a front contact of said first control relay and a contact of said controller closed at the vertical position of the gate, an operating circuit including a front contact of said repeater relay and a contact of said controller closed except at said vertical position connected to said motor to energize the motor, a circuit including a front contact of said first control relay connected to said holding winding to energize that winding, an auxiliary circuit means including contacts of said controller closed except at said horizontal and at said vertical positions, a contact closed only when said first control relay is picked up and a back contact of said second control relay connected to said draw up winding to energize that winding, and control means adapted to respond to traffic conditions and having connections to said first and second control relays to govern the energization of said first and second relays.

12. In combination with a highway crossing gate mechanism operable to a horizontal position and provided with an electric motor adapted when energized to drive the gate to a vertical position and with a multiple contact controller actuated by movement of said mechanism and with a slot magnet having a draw up and a holding winding, control apparatus for holding the gate mechanism at a position intermediate the horizontal and vertical positions comprising in combination, a first control relay having a selected slow release period, a quick acting second control relay, a repeater relay having an energizing circuit including a front contact of said first control relay,

19 another control relay having an energizing circuit including a front contact of said second control relay; an operating circuit including a front contact of said repeater relay, a contact of said controller closed except at said vertical position and a front contact of said another control relay connected to said motor to energize the motor; a circuit including a front contact of said first control relay connected to said holding Winding to energize that winding; an auxiliary circuit means including a back contact of said another control relay, a contact of said controller closed except at said vertical position and a front contact of said repeater relay connected to said draw up winding to energize that Winding; and control means responsive to trafiic conditions and having connections to said first and second control relays to govern the energization of said first and second relays.

13. In combination with a highway crossing gate mechanism having an arm operable to a substantially horizontal position and provided with an electric motor adapted when energized to raise the arm to a substantially vertical position, said mechanism being provided with a multiple contact circuit controller actuated by the mechanism and with a slot magnet adapted when eifectively energized to latch the mechanism against movement of the arm toward the horizontal position, holding the mechanism with the arm at any intermediate point between the horizontal and the vertical positions for a selected time interval and then allowing the arm to be moved toward the horizontal position comprising a first control relay having first and second conditions and requiring a predetermined time interval to operate from said first to said second condition, a quick acting second control relay having first and second conditions, control means having a first and a second condition, circuit means governed by said control means and having connections to both of said control relays for operating both of said control relays to their first conditions under said first condition of said control means and to operate both of said control relays to their second conditions under said second condition of said control means, an operating circuit means controlled by said second control relay and said circuit controller and efiective when said second control relay is in said first condition and said gate mechanism is not in said vertical position connected to the motor of said gate mechanism for energizing said motor, a normal slot magnet circuit means controlled by said first control relay and said circuit controller and effective when said first control relay is in said first condition and said gate arm is in a position just prior to the vertical position connected to the slot magnet of the gate mechanism for effectively energizing said slot magnet; an auxiliary slot magnet circuit means controlled by said first and second control relays and said circuit controller and effective when said first control relay is in said first condition, said second control relay is in said second condition and said gate mechanism is occupying a selected range of positions connected to said slot magnet control apparatus f 25 for effectively energizing said slot magnet.

References Cited in the file of this patent UNITED STATES PATENTS 1,879,919 Butterworth et al. Sept. 27, 1932 2,137,196 Sampson Nov. 15, 1938 2,312,758 Goodlin Mar. 2, 1943 2,368,745 Crago Feb. 6, 1945 2,435,824 Goodlin Feb. 10, 1948

Images