US3730360A

US3730360A - Unit train automatic unloading system

Info

Publication number: US3730360A
Application number: US00145676A
Authority: US
Inventors: H Aquino; W Knippel
Original assignee: Pullman Inc
Current assignee: Pullman Standard Inc; Pullman Inc
Priority date: 1971-05-21
Filing date: 1971-05-21
Publication date: 1973-05-01
Anticipated expiration: 1990-05-01

Abstract

An automatic control system for regulating the opening and closing of railway hopper car discharge doors and including an electrical and a hydraulic system which senses the approach of a unit train to actuate trackside cam and sensing means to discharge the load, such as, coal into below track pits. Pit sensors sense the height of the coal in each successive pit and signal the electrical and hydraulic control system to prevent discharge of coal into a full pit. Safety control means are included in the system to prevent the door opening cam track means from being raised under the locomotive and from being raised under the caboose. The speed sensor in the control circuit will determine if the train is approaching at too high velocity, and will lower the cam devices and the sensing devices away from trackside so as not to be damaged by the approaching overspeed train.

Description

United States Patent [191 Aquino et al.

May 1, 1973 UNIT TRAIN AUTOMATIC UNLOADING SYSTEM [75] Inventors: Herman A. Aquino, Hobart, lnd.;

Willis H. Knippel, Palos Park, 111.

[ 73] Assignee: Pullman Incorporated, Chicago, 111. [22] Filed: May 21, 1971 21 Appl. No.: 145,676

[52] U.S. Cl. ..214/63, 105/241 C [51] Int. Cl ..B65g 67/24 [58] Field of Search ..214/58, 63; 105/241 C [56] References Cited UNITED STATES PATENTS 3,080,075 3/1963 Giesking ..214/63 3,446,373 5/1969 Keister et a]. .....214/63 3,433,373 3/1969 Carey et a1. 1 ..2l4/63 3,041,448 6/1962 Pascoe et a1 ..214/58 X Primary Examiner-'Robert G. Sheridan Attorney-Hilmond O. Vogel and Richard J. Myers 15 7] ABSTRACT An automatic control system for regulating the opening and closing of railway hopper car discharge doors and including an electrical and a hydraulic system which senses the approach of a unit train to actuate trackside cam and sensing means to discharge the load, such as, coal into below track pits. Pit sensors sense the height of the coal in each successive pit and signal the electrical and hydraulic control system to prevent discharge of coal into a full pit. Safety control means are included in the system to prevent the door opening cam track means from being raised under the locomotive and from being raised under the caboose. The speed sensor in the control circuit will determine if the train is approaching at too high velocity, and will lower the cam devices and the sensing devices away from trackside so as not to be damaged by the approaching overspeed train.

23 Claims, 10 Drawing Figures PATENTEU H973 sum 1 hr 4 INVENTORS HERMAN A. AOUINO WILLIS H. KNIPPEL PAT AGENT v PATENTEI] m 1 m3 sum 3 or 4 INVEN TORS HERMAN A. AQUINO WILLIS H. KNIPPEL Ea MM ar a GENT M PATENTEDMM 1 1973 sum u 0F 4' Ill" 0 All INVENTDRS HERMAN A. ounvo WILLIS H KNIPPEL 2 PA? AGENT QBY UNIT TRAIN AUTOMATIC UNLOADING SYSTEM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention pertains to a railway hopper car automatic discharge control system.

2. Description of the Prior Art Existing prior art automatic hopper door opening arrangements generally include mechanisms aimed at opening and closing the hopper doors ata given point as the train passes over a discharge pit. Sensing devices generally embodied in present automatic discharge devices are located only at the point of opening of the hopper generally directly above the trackside mechanism. Problems are encountered with this type of opening arrangement and sensing mechanism since only one sensor is used to sense the position of the hopper car and since all the car lading is discharged at the same point for all cars the pit into which the lading is discharged will build up specifically at the point directly below the opening mechanism. This is somewhat troublesome since pits are generally very large and are not utilized to their fullest capacity because of a lading peak in the pit below the point where all the cars are opened. The sides and ends of the receiving pit are oftentimes not fully utilized. Another difficulty with prior art hopper discharge mechanisms and sensing devices is that the mechanism has no facility for sensing the approach of the train or for sensing the passage of the train. This requires a manual operation to lift the cam track or other trackside actuating device into position after the locomotive has cleared and requires a second manual operation to lower the actuating track or the actuating mechanism or trackside device after the caboose has passed over the discharge area. It is necessary to lower the trackside actuating device because of the generally low or varying clearances between the top of the rails and the bottom of both the locomotive and the caboose.

The present invention overcomes these difficulties with a combination of an electrical sensing circuit coupled with a hydraulic circuit to perform the sensing and mechanical functions. An electrical sensing circuit detects the approach of the train and automatically raises and lowers trackside actuating devices.

The control system of the present invention is adapted to be used with the structure of a door operating mechanism shown and disclosed in U. S. Pat. No. 3,459,317 to William R. Shaver which application is assigned to the assignee of the present invention and incorporated herein by this reference thereto.

SUMMARY OF THE INVENTION The invention involves a train sensing and hopper car door opening and closing system having train sensing devices positioned at trackside to sense both the approach of the train and the open or closed condition of the hopper doors. An automatic electrical sensing circuit which is operated by an approaching train is coupled to a hydraulic power circuit which raises and lowers hopper door opening and closing members. Sensing switches positioned at trackside sense the depth of the discharged lading at various points along the discharge area to sense a predetermined build-up or level at which point no additional hopper cars'will be discharged at the point of ladingbuild-up.

An object of the present invention is to provide a train sensing and hopper car door operating system which is actuated by the approach of a unit train having hopper cars to thereby raise and lower hopper car door opening and closing devices.

It is another object of the present invention to provide a unit train sensing system, including an electrical circuit coupled with a hydraulic circuit, which also senses the condition of the hopper doors of the cars included in the train to determine whether a door opening mechanism should be raised to open the doors and discharge the lading of the hopper cars.

A further object of the present invention is to provide discharged load depth sensing devices at various points along the discharge area adjacent the tracks to permit progressive tilling of the discharge and storage pits and insuring complete utilization of the available pit area.

Another object of the present invention is to provide trackside sensing devices which sense the approach of a particular type of train to turn on the sensing system of the present invention and also to provide sensing devices which sense the passage of the train to de-energize or turn off the sensing system, thus rendering the trackside system fully automatic.

It is also an object of the present invention to provide a sensing device and a system to sense the approach speed of a train and if the velocity is in excess of a predetermined maximum speed to thereby de-energize or de-activate the sensing and actuating mechanisms associated with the system to prevent their damage by a train moving at a prohibitive velocity.

Another object of the present invention is to provide a hopper door operating system having safety switches or safety sensor employed in the system to sense the open or closed condition of the hopper cars in the approaching train to prevent inadvertent raising of a door opening track or mechanism to open hopper doors that have already been opened at a prior station.

It is a further object of the present invention to provide automatically actuated hopper door unlocking devices positioned at trackside and operable on the approach of a train.

These and other objects of the invention will become apparent from reference to the following description, attached drawings and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a unit train having a locomotive, caboose, and two intermediate hopper cars of the type involved with the present invention;

FIG. 2 is a top plan view of the train illustrated in FIG. 1 showing in particular the actuating devices extending transversely from the cars of the train;

FIG. 3 is a schematic of the portion of the electrical circuit involved in the control of the hopper discharge at the beginning of the hopper car discharge area;

'FIG. 3a is an electrical schematic diagram showing the remainder of the circuit illustrated in FIG. 3 and showing in particular the circuitry involved at the 0105- ing station at the end of the hopper car discharge area; FIG. 4 is a schematic of the hydraulic circuit involved;

FIG. 5 is a partial sectional view of the side sill area of a hopper car and showing in particular the circuit actuating device or flag which is rotated into the phantom line position upon opening of the hopper car doors;

FIG. 6 is a partial sectional view of the device which is actuated by the flag illustrated in FIG.

FIG. 7 is a view taken along line 7-7 of FIG. 6;

FIG. 8 is a side elevational view of the hopper door mechanism locking bar in a raised or unlocked position with its associated lifting cam device; and

FIG. 9 is a top plan view of the device as illustrated in FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings and in particular to FIG. 1 which illustrates the typical makeup of a unit train 10 which is involved in the present invention, the unit train (includes only a particular type of car) is comprised of a locomotive unit 11 and hopper cars 12 with a caboose member 13 at the end of the unit train. Only two hopper cars 12 are illustrated; however, a unit train contemplated to be utilized with the invention is not limited to any particular number of cars. As indicated in FIGS. 1 and 2, actuating members or flags are positioned on the cars comprising the unit train and these actuating devices engage trackside readers and sensing switches which control the opening and closing of the hopper car doors. At the rear of the locomotive 11 is a locomotive mounted switch actuating tripping member or flag member 14 which extends transversely of the locomotive. Positioned on the hopper cars 12 are hopper door actuated indicators or flags 15 which also extend transversely of the hopper cars when the hopper car doors are open to indicate the opened condition to sensing devices at trackside. The caboose 13 includes a pair of actuating members including a first caboose mounted switch actuating tripping member or flag 16 at the forward portion of the caboose and a second caboose mounted switch actuating means or indicator flag 17 positioned at the central portion of the caboose, and extending outward of the caboose at the same level as the hopper door indicators 15. The locomotive flag 14 and the caboose tripping member 16 are positioned at different levels to permit actuation of their associated sensing members.

FIGS. 5, 6, and 7 illustrate the mechanical configuration of the hopper door indicator 15 which includes a motion multiplying type of mechanism which rotates the door indicator 15 a greater degree than the amount of movement of the actuating doors 18. As illustrated in FIG. 5, the hopper car 12 includes longitudinally extending hopper doors 18 rotatable from the position illustrated in FIG. 5 to an approximate vertical position. The doors 18 are pivoted at 19 which is a pivot point in the area of the side sill 20. The hopper construction includes slope sheet 21 to direct the discharge of the load, such as coal. The hopper door indicator 15 is rotated by a mechanism connected to the hopper door 18 and having a link 22 connecting the door 18 with a slide member 23 to produce movement of the slide member 23 outward of the hopper car upon rotation of the hopper door 18. This outward movement of the slide member 23 produces a multiplied rotation of the hopper door indicator flag 15. Thus the limited and relatively small rotation of the hopper doors is multiplied to move the hopper door indicator 15 an amount to protrude sufficiently from the railway hopper car to actuate trackside readers or sensing devices. The hopper door indicator 15 includes an arm portion 24 extending away from the pivot 19 and having a bar or contact member 25 welded to its outer end.

As indicated in FIG. 6, a typical trackside reader or sensing device 26 is illustrated with the associated typical mechanical components. The trackside reader 26 includes a pivoted arm 27 having

telescoping portions

28, 28a which permit a height adjustment of the pivoted arm. At the upper end of the arm 27 is buffer or contact portion 29 which includes a roller 30. Extending from the pivoted arm 27 is a follower linkage 30a which converts the rotation of the am into reciprocating horizontal movement of the cam 31 which actuates the limit switch 32. The limit switch 32 is enclosed in a housing 33 to protect it from the elements. The indicator light 34 positioned atop the housing 33 indicates when the limit switch 32 or associated circuitry is actuated.

Each hopper car 12 includes a hopper door actuating mechanism as described in US. Pat. No. 3,459,317 issued to W. R. Shaver on Aug. 5, 1969 and incorporated herein by reference. This patent describes a rotary type of hopper door opening mechanism having a crank or arm which has portions protruding vertically downward from the hopper car and engageable with a cam track of the trackside mounted door operating means which is positioned between the rails. When this rotary crank type of door operating mechanism is utilized the hopper car also includes a locking lever such as that illustrated in FIGS. 7 and 8. The rotary crank of the door operating mechanism is illustrated in FIGS. 7 and 8 and indicated by the numeral 35. A locking lever 36 is pivoted at 36a and includes a lock lifting cam portion 38 and a lock lowering cam portion 39. The pivot includes a fastening device such as a bolt as illustrated constraining a pair of Belleville springs which are biased to keep the locking lever in a raised position upon actuation by trackside cam 40.

The trackside cam 40 is a pivoted and vertically movable actuating member which is raised and lowered upon operation of the hydraulic cylinder 41. The hydraulic cylinder 41 is controlled by a hydraulic circuit which is in turn controlled by the electric sensing circuit included in the present invention. The piston of the hydraulic cylinder includes a plunger 42 and a spring 43 to cushion any impact resulting from the operation of the power cylinder in raising the trackside cam 40. It is noticed that the lifting cam section and the lowering

cam section

38 and 39 respectively are offset (see FIG. 9) so as to provide independent actuation from a raising and a lowering type of cam attached to an associated hydraulic cylinder.

An additional type of train carried actuated device or flag is positioned on the locomotive and indicated by the numeral 14 and also positioned on the caboose and indicated by the

numerals

16 and 17. This actuating device or flag is a manually positioned actuating arm which extends traversely from the car of the train to engage a trackside switch. This arm is similar to the hopper door indicator arm 15 insofar as these flags also include a bar or contacting member similar to that indicated in FIG. 7 by the numeral 25 which engages a switch or a switching actuating device.

The electrical and hydraulic circuitry coupled with the mechanical equipment involved in the present invention are aimed at controlling the discharge of lading from a unit train. The discharge of various hopper cars of the unit train can be controlled along the length of a single discharge pit or can be controlled between individual spaced discharge pits. To obtain this controlled discharge, the present invention includes, along with other components, a transmitter and receiver combination, the transmitter emitting a radio signal from the locomotive 11 of an approaching unit 12. This signal is received by the receiver illustrated in FIG. 3 and denoted by the letter R. The radio signal from a transmitted on the locomotive 11 is received by the antenna indicated by the letter A and actuates switching circuitry within the receiver to switch on the main power relay 45 which in turn energizes the circuit by applying line power indicated by the letter P which is generally 110 volt AC power supply. The main power relay 45 is the common electro mechanical type having a coil or winding 46 and a pair of normally open contacts indicated at 47 and 47 Electro mechanical switching devices are indicated in the circuitry of the present invention; however, the invention is not limited to these electro mechanical devices and transistorized or integrated circuit switching devices can be used.

As illustrated in FIG. 3 the discharge pit is indicated by the numeral 1 and has a rectangular enclosed area which is a trackside area into which the lading of hopper cars is to be discharged. Enclosed within the perimeter of the pit and illustrated in FIG. 3 are a pair of lading depth sensors which are commercially available and will sense the depth of lading in the pit. When the discharged lading reaches a certain height the contacts associated with the depth sensors will open. Also outside the perimeter of pit l is a limit switch 14a and just inside the perimeter is a second limit switch 141). As noticed, these light switches are adjacent a line indicated by the letter L. Switches on the line L are actuated by the locomotive tripping member 14. The switch 14a includes normally

open contacts

49 and 50 which move in unison in response to movement of the switch 14a by the locomotive flag 14. Associated with the limit switch 14a is a solenoid 51, a switching relay 52 having an associated normally open contact pair 52a, and an indicator light 53. Associated with the solenoid 51 and in the hydraulic circuit is the solenoid activated valve 51a which controls flow of hydraulic fluid to the cylinder 41. The locomotive tripping member 14 is illustrated schematically in FIG. 3 adjacent the switches 14a, 14b.

Limit switch 14b which is within the perimeter of the pit 1 is a limit switchhaving a normally open contact 55. Associated with this limit switch is a solenoid 56, a

switching relay 57 having normally open contacts 57,.

57a, and an indicator light 58. Associated with the solenoid 56 is a solenoid valve 56a which regulates the flow of hydraulic fluid to the cylinder 56b. I

The limit switch 16a positioned in front of the pit area number 1 and adjacent the horizontal line denoted by the letter C in FIG. 3 includes a single normally closed contact 60. Furthermore, in the remainder of the specification, all limit switches were are adjacent the horizontal line indicated by the letter C are limit switches which are actuated by the caboose tripping member l6.

The devices indicated by the

numerals

61, 62, 63 and 64 are depth sensing devices which are commercially available on the market. Each sensing device has an associated normally

closed contact

61a, 62a, 63a, and 64a, respectively. These pit sensors sense the depth of coal in a given pit area and when a particular depth is reached, the normally closed contacts will open.

A relay coil 65 which is in series with the limit switch 16a has a pair of normally open contacts 65a, 65b.

The receiver R also includes a speed sensing device which may be inductive devices positioned at trackside, optical devices or even a radar type of pulse emitted from the receiver R to sense the speed of an approaching train. If the speed is prohibitive, the receiver R will actuate the relay 66 which has a single normally closed contact pair 66a which is then opened.

Referring now to FIG. 3a for a description of the circuitry and mechanical sensing equipment involved at a second pit indicated by the numeral 2, horizontal lines indicated by letters a, b, c, d are continuations of horizontal lines similarly indicated in FIG. 3. A mechanical latching relay 67 having a pair of coils 67a, 67b and a single normally open contact pair 68 is located in the circuit and actuated by a railway car passing through pit 2. The contacts 68 are closed when the coil 67a is energized and the contacts 68 remain closed by a mechanical latch after the coil 67a is deenergized. Upon actuation of the coil 6712, the mechanical latch is disengaged and the contacts 68 are allowed to open.

At pit 2, limit switches which are actuated by the locomotive tripping member 14 are adjacent the horizontal line indicated by the letter L to indicate locomotive actuated limit switches. Switches actuated by the hopper door indicators 15 are adjacent the line indicated by the letters DR indicating door. The limit switch actuated by the caboose indicator 17 is adjacent the horizontal line indicated by the letter C. The

locomotive tripping member is illustrated schematically in FIG. 3a and indicated by the number 14.

Pit 2 is traversed by the train moving from the right to the left as illustrated in FIG. 3a. The limit switch 69 which is actuated by the hopper door indicator 15 includes a single normally closed contact 69a.

The second limit switch at the entrance to pit 2 is indicated at 70 and includes a normally closed contact 70a and a normally open contact 70b. A third limit switch at pit 2 is indicated at 71 and includes a normally open contact 71a. This limit switch 71 is actuated by the locomotive tripping member 14. Associated with the locomotive actuated limit switch 71 is a solenoid 72 which actuates the valve 72a in the hydraulic circuit to operate the hydraulic cylinder 72b. Also associated with the limit switch 71 is a relay coil 73 and an associated pair of normally open contacts 73a. An indicator light is represented at 74.

A fourth limit switch 75 is actuated by the hopper door indicators 15 and includes a single normally open contact pair 75a.

At this point it should be noted that any additional pits which would be necessary or utilized with the present invention would have the circuitry and mechanical components identical with those utilized at pit 2 and previously described.

The hydraulic circuit illustrated in FIG. 3 includes a reservoir 76 and a pump 77 driven by the motor m. Filters f filter the hydraulic fluid coming to and from the reservoir 76. A safety valve 78 prevents damage to the hydraulic circuit if a blockage or other similar situation would occur. A needle valve 79 and a pressure guage 80 are used to obtain the line pressure. Hydraulic accumulators 800 are pressurized hydraulic fluid to provide for fluid flows which cannot be provided by the pump 77.

The trackside actuating devices and limit switches which are positioned at the end of the pit area are illustrated at the upper left portion of the circuit diagram of FIG. 3a. Adjacent the line designated by the letter L is a limit switch 81 which is actuated by the locomotive tripping member 14 and operates a circuit connected with a hydraulic cylinder to raise and lower the first part of a two-part cam track which closes the hopper car discharge doors. Associated with the limit switch 81 is a normally open contact 81a, a solenoid 82 which operates the control valve 82a of hydraulic cylinder 82b in the hydraulic circuit to raise and lower the first part of the hopper car discharge door closing cam track (not illustrated). A relay 83 is also associated with the limit switch 81 and has a pair of normally open contacts 83a operatively connected thereto. An indicator light 84 is associated with the relay 83 to indicate when the relay is energized. A second limit switch 85 is operated also by the locomotive tripping member 14 and functions to actuate circuitry which raises the second portion of the closing door cam track. The hydraulic components associated with this limit switch 85 include valve 850 and cylinder 85b. The electrical circuitry is identical with the circuitry illustrated as associated with the limit switch 81 and has been omitted from the schematic diagram for purposes of clarity.

A third limit switch 85 is also actuated by the locomotive tripping member 14 and functions to actuate electrical circuitry and hydraulic equipment, valve 86a and cylinder 86b, at the end of the door closing operation to move the locking lever 36 of the hopper door mechanism into position to prevent unintentional opening of the hopper doors. The electrical circuitry associated with this limit switch 86 is illustrated at the bottom center of FIG. 3a and also includes the usual normally open contact 860 with a solenoid 86d and a relay 862 having an associated normally open contact 86fand an indicator light 86g.

The limit switches 81, 85, 86 are all actuated by the locomotive tripping member 14 at the end of the pit discharge area. The reason for separating the closing cam track into a first and a second section is to permit sequential lifting of the lengthy cam track as the locomotive passes over the track and also to insure that the cam track is not lifted inadvertently up underneath the locomotive when sufficient clearance is not provided which would cause damage to the cam track.

As illustrated in FIG. 3a, there are

first limit switches

87, 88 and second

light switches

89, 90 adjacent the horizontal line indicated by the letters DR and which are actuated by the hopper door indicators of each hopper car and also actuated by the caboose indicator 17. Also, as noted from the schematic, the hopper car actuated

limit switches

87, 89 and the locomotive actuated limit switch 81 operate in conjunction with each other and will be more fully explained further on in the specification. The limit switches 88, 90, and 85 also operate in conjunction with each other and include circuitry identical with that illustrated as associated with the three just mentioned limit switches. The circuitry is omitted here for purposes of clarity.

Associated with the limit switch 87 is a normally closed contact 87a. The limit switch 89 includes a pair of normally open contacts 89a, 89b; and the limit switch 90 has a similar pair of contact pairs. Switches 87a and 8917 are in parallel with each other. Normally open contacts 81a, 89a, and the latching contacts 83a of relay 83 are also in parallel. These two parallel connections are in series with each other. Thus, to energize solenoid 82 at least one switch of each parallel pair must be closed simultaneously.

At this closing station there are also three

limit switches

91,92,93 adjacent the horizontal line indicated by the letter C. These three limit switches are actuated by the caboose tripping member 16 and function to de-energize the control circuit. The limit switch 91 has a single normally closed contact pair 91a and functions to lower the first part of the door closing cam track. It is to be understood that the limit switch 92 lowers the second part of the door closing cam track and also includes a single normally closed contact and associated circuitry which has been omitted here for purposes of clarity. The limit switch 93 which is actuated by the caboose tripping member 16 functions to lower a hydraulically operated cam which engages the cam portion 39 of each locking lever 36 to move the locking lever 36 on the hopper car into locking engagement with the door operating crank 35. The circuitry associated with this limit switch 93, for purposes of clarity, has been illustrated at the bottom of the diagram in FIG. 3a. Limit switch 93 includes a normally open contact pair 93a and a normally closed contact pair 93b.

Associated with the limit switch 93 is a mechanical latching relay 95 having a pair of coils 95a, 95b and a single normally open contact 950. This relay is designed so that the coil 95a will initially close the contact 950 when a momentary pulse is applied to the coil 95a. The relay also includes a mechanical latch which keeps the contacts closed after the pulse is released from the coil 95a. To open the contacts 950 and the coil 95b is operated to release the mechanical latch and permit the contacts to open.

THE OPERATION The method of operation will be best understood by referring to FIG. 3 and the pit indicated by the numeral 1 with the explanation aimed at describing the operation of the system as a unit train progresses from right to left across the pit area illustrated in FIG. 3 and FIG 3a. As the unit train 10 approaches pit l, a radio signal emitted from a transmitter on board the locomotive 11 is received through the aerial A of the receiver R illustrated in FIG. 3. Upon receipt of this ratio signal the receiver will energize the coil 46 of the main power relay 45 thereby closing the normally open contacts 47, 47'. In closing the contacts of the main power relay 45 line voltage is applied to the control circuit. Thus upon actuation of the relay 45 the line voltage is available at the contacts of the limit switch and at the limit switch 14b, limit switch 16, as well as at associated contacts of the pit sensors 6.1, 62, 63, and 64. The speed control relay 66 has a normally closed contact 66a and applies line voltage at contact 950 of the latching relay 95 to thereby make available the line voltage to the cam lowering section at the end of the pits when contact 95c is closed. Thus the overspeed relay 66 which is operated through the receiver R operates to lower the door door closing cam by opening contacts 66a in the event a train is approaching the pit area at a rapid or high velocity. The overspeed relay 66 also controls the voltage applied to the solenoid 56 to thereby lower the door opening cam when an overspeed train approaches.

It is noticed that the locomotive 11 has the tripping member 14 extending transversely therefrom and will initially engage the limit switch 14a. Upon engaging the limit switch 140 the

contacts

49 and 50 are closed momentarily to thereby apply a voltage across the solenoid 51 and the relay 52. Energizing the relay 52 closes the normally open contacts 52a and thereby enables the relay 52 to be self-locking or holding upon the application of a momentary pulse through the contact 50. Contacts 52a remain closed after contact 50 is reopened. upon operation of the solenoid 51 the associated solenoid valve 51a in the hydraulic circuit is operated to power the hydraulic cylinder 41 to thereby raise the trackside door lock lifter cam 40 into position to unlock the locking bars 36 from the operating crank 35 of the hopper door operating mechanism. Indicator light 53 signals that contact 52a is closed.

It is also noted that when the relay coil 46 is energized the coil 65 (located at left center of FIG. 3) is also energized closing the normally open contacts 650 and 65b and thereby applying the line voltage across the normally closed contacts 61a, 62a of the pit depth sensors.

As the locomotive proceeds from the limit switch 14a towards the limit switch 14b and the locomotive tripping member 14 engages the switch 14b closing the normally open contacts 55, the line voltage will be applied across the solenoid 56 and across the relay coil 57 as well as the indicator lamp 58. Energizing the solenoid 56 operates the valve 56a in the hydraulic circuit to send fluid to the hydraulic cylinder 56b to thereby lift the door opening cam track into position between the rails. This voltage also operates the relay 57 to close the associated normally open contacts 57 a thereby making the relay 57 self-latching so that it remains operated when the Contact 55 is opened as the locomotive passes the limit switch 14b. Thus it is noticed that after the locomotive has passed the limit switch 14b the cam track will have been raised into position between the rails to operatively engage the hopper cars. When the locomotive passes the two locomotive associated limit switches 14a, 14b the door unlock cam member 40 will have been raised into position to lift the locking bar 36 from its locking position on the hopper ill cylinder 56b to lower the hopper door opening cam track from its raised operative position. Another condition which would lower or de-energize the hydraulic cylinder 56b would be the approach of a unit train at a prohibitive velocity which would be sensed by the receiver R causing the speed control relay 66 to operate thereby opening the normally closed contacts 66a which are also in series with the solenoid 56 and which when opened will de-energize the solenoid and consequently lower the cam track from the raised between-rail position.

As the hopper cars proceed past the pit 1 and the caboose approaches, the caboose tripping member 16 will engage the limit switch and open the normally closed contact 60. Opening the contact 60 which is in series with the relay coil 65 opens the contact 65a, 65b to thereby remove applied voltage from the solenoid 56 and from the solenoid 51 to thereby lower the cam track from the raised position and also lower the door unlocking cam 40 from its raised position. The trackside cam 40 is lowered with the cam track to insure sufficient clearance for passage of the caboose over this area adjacent to the front of pit 1.

Referring now to FIG. 3a, and in particular to pit 2 and the circuitry connected therewith, it is noticed that pit 2 is a typical pit representing the configuration circuitry associated with all pits, other than pit 1. Once again, the first vehicle in the unit train to approach the pit area is the locomotive 10. Consequently, the first switch actuated will be the limit switch 71 which closes the normally open contact 71a in response to actuation by the locomotive tripping member 147 This momentary closure of the contact 710 energizes the solenoid 72 which operates the valve 72a in the hydraulic circuit and powers the hydraulic cylinder 72b to lift the door opening cam track into operative position Momentary closure of the contact 71a also pulses the relay coil '73 causing the contact 73a to be closed whereby the relay 73 will be self latching or holding when the contact 71a is re-opened. The indicator light 74 indicates that the contact 73a is closed. It is noticed that the contact 73a is in series with the contacts 63a, 64a of the pit sensors which will prevent the solenoid 72 and the relay 73 from operating if the depth of lading in the pits has reached a predetermined level causing the contact 63a, 64a to open and drop out the solenoid 72 and the relay 73.

Following the locomotive are the hopper cars 12 of the unit train 10 which actuate the limit switches adjacent the horizontal line indicated by the letters DR. The first limit switch to be actuated by the open hopper cars discharge doors and their associated indicators 15 is the limit switch 69 which, when actuated, will open its normally closed Contact 69a which is in series with the solenoid.72 and the relay 73 to lower the door opening cam track from its raised operative position if the hopper car doors have been opened at the previous pit. The limit switch 69 being actuated by the hopper door indicator 15 is only actuated when the hopper doors have been opened and the hopper door indicator has been moved outwardly of the car to actuate the trackside limit switches as indicated by the phantom line representation in FIG. 5. As the train progresses over the pit area, the hopper car having doors open which has actuated limit switch 69 progresses toward limit switch 75 in which case the hopper door indicator will engage the limit switch 75 and close its normally open contact 750 causing a momentary pulse to be applied to the solenoid 72 and the relay 73 actuating both members as aforementioned in the same manner as they are actuated when the contact 71a is closed momentarily. Thus it is seen that a hopper car which approaches a pit and has had its hopper doors opened at a previous pit will sequentially initially engage the limit switch 69 to lower the door opening cam track and then engage the limit switch 75 to raise the cam track after the car with the doors open has passed the door opening cam track area. This limit switch 75 is intended to raise the cam track into operative position to engage the successive hopper car of the train.

As the caboose approaches the pit area number 2 the caboose tripping member 16 will engage the limit switch 70 and open the normally closed contact 70a at the same time closing the normally open contact 70b. This switching caused by the engagement of the caboose tripping member 16 with the limit switch 70 and opening of normally closed contact 70a which is in series with the solenoid 72 and relay 73, deenergizes the solenoid 72 and the relay 73 to drop the hopper door opening cam track from the raised position to clear the caboose 13. Also, closing the contact 70b, which is part of limit switch 70, pulses the relay releasing coil 67b of the mechanically latching relay 67. It should be noted at this point that the relay coil 67a was initially operated by a momentary pulse applied as the normally open contact 49 of the limit switch 14a was actuated by the locomotive. This mechanical latching relay kept the contact 68 closed when the contacts 49 reopened. To open the contacts 68 it is necessary to pulse the coil 67b which is done by the contacts 70b which are closed when the caboose tripping member 16 passes the limit switch 70. Thus, after the caboose has passed and the contacts 70a, 70b return to the position illustrated in FIG. 3a, the door opening cam track will remain lowered since contacts 68 of relay 67 have been opened thereby cutting off current flow to solenoid 72.

Referring now to the upper left portion and the lower left portion of FIG. 3a, the discharge door closing sequence of operation will be described. Once again, the limit switches adjacent the horizontal lines denoted by the particular letters L for locomotive, DR for door, and C for caboose, will be actuated respectively by the locomotive tripping member 14, the hopper door indicator l5, and the caboose tripping member 16. Limit switches adjacent the line DR are also actuated by the caboose indicator 17. The first vehicle of the train to approach this closing station is the locomotive 11 which will actuate the limit switch 81 and thereby close the normally open contact 810 which, in turn, energizes the solenoid 82 and the relay 83 and the indicator light 84. Energizing the solenoid 82 will operate the associated hydraulic valve 820 to pass fluid to the hydraulic cylinder 82b which, in turn, raises the first part of the two-section door closing cam track. The closing cam track is a relatively lengthy member and is broken into two portions for sequential raising of the first and second portion to provide clearance as the locomotive passes over the track and yet permit the first part of the cam track to raise up to engage the hopper door actuating mechanism while the second part is still in a lowered position.

A second limit switch controls the second part of the closing cam track and has circuitry associated with it which is identical to the circuitry illustrated as associated with the limit switch 81 which controls raising and lowering of the first part of the closing cam track.

The limit switch 86 shown in its position relative to the other limit switches at the top left of FIG. 3a and with the associated circuitry at the bottom center of FIG. 3a controls a trackside cam which is raised and lowered to engage the locking bar 36 which is moved into position to lock the hopper door crank 35 after the crank has been rotated to an overcenter closed position by the closing cam track portions. The circuitry associated with the limit switch 86 includes the normally open contact 860, solenoid 86d, relay 86c, associated normally open contact 86f and indicator light 86g.

Following the passage of the locomotive, it is noticed that the cam track will have been raised into position between the rails and the door locking cam associated with the limit switch 86 will have been moved into operative position to lock the doors after hopper door operating mechanism of each car has been operated by the door closing cam track.

The next sequence of operation involves limit switches operated by the hopper door indicators 15. Following passage of the locomotive the first limit switch to be engaged by the first hopper door indicator 15 is the limit switch 87 which will open the associated normally closed contact 87a. It is noticed that this contact 87a is in series with the contact 83a which passes current to the solenoid 82 and the relay 83. Therefore, when the contact 87a is open the solenoid 82 will be de-energized along with the relay 83. Thus the first part of the cam track is lowered from its raised operative position.

As the first hopper car following the locomotive with the doors open progresses to the limit switch 88 the same functions occur since the limit switch has circuitry connected to it which is identical with the circuitry associated with the limit switch 87. Therefore, upon passage of a hopper car having its hopper doors open, the hopper door indicator 15 will successively actuate the limit switch 87 and then the limit switch 88 thereby effectively lowering both portions of the discharge door closing cam track from the raised to a lowered inoperative position. The exact purpose or objective in having this initial lowering of the cam track sections when a hopper car approaches having its doors open will be more fully appreciated further in the succeeding explanation of the operation.

As the hopper car with the hopper doors open proceeds from the limit switches 87, 88, with the door operating cam tracks now lowered, to the second pair oflimit switches 89, actuated by the hopper door indicator 15, a succeeding hopper car will approach the limit switches 87, 88. Because of the designed spacing between the hopper car door indicators 15 and the spacing between the pairs of

switches

87, 88 and 89, 90 the system is designed so that the adjacent hopper cars will both approach and contact the pairs of limit switches at the same time. As this is occurring, it is understood that the car at limit switch 87 is opening the contact 870 and thereby generating a signal to lower the door closing cam track. Also, at the same time the limit switch 87 is being actuated, the preceding car is actuating limit switch 89 which is giving an up cam signal to the door opening cam track by closing contact 89a and 89b. The actuation of the limit switches 87, 89 by adjacent hopper cars is so designed that the signal given to lower the cam track when the limit switch contact 87a is opened is overridden by the up cam track signal generated upon closing of the normally open contacts 89a. The sequence of operation of the limit switches 87 and 89 is designed so that successive adjacent hopper cars with hopper doors open at no time will cause the contact 87a and the contact 890 to be open at the same time which would result in the closing cam track remaining lowered and hopper doors not being closed. This result may be achieved, for instance, by including a lengthy contact member at the limit switch 89 which produces a longer switch actuating time as the hopper car passes the limit switch. A shorter contact period is contemplated for the limit switch 87 thereby insuring a condition wherein the contact 89a will be closed when the contact 87a is open.

Thus it is noticed that once the cam track is lifted by the passage of the locomotive the first hopper car entering the door closing area and having doors open will cause an initial lowering of both cam track sections as the hopper car indicator 15 passes the limit switches 87, 88. As the same car approaches and passes the limit switches 89 and 90 the two-section door closing cam track will be relifted into an operative between-rail position. Thereafter, passage of successive hopper cars with doors open will result in the door closing cam track remaining in a raised position. The purpose of the two opposite signals-one to raise the door closing cam track and the other to lower the door closing cam trackis to insure that a hopper car with unopened discharge doors will not have the door closing cam track raised as it passes over which would damage the door opening mechanism. A car with unopened discharge doors would not actuate any limit switch; however, a succeeding car with open discharge doors would supply actuation to limit

switches

87, 88 to lower the discharge door closing cam tracks as the car with unopened doors approached thus preventing damage.

The final operation of the control system is accomplished by the caboose 13 and both its associated tripping member 16 and the caboose indicator 17. The caboose indicator 17 corresponds in height and in distance extended beyond the side of the caboose to the positioning of the hopper door indicator l5 and will therefore actuate the same limit switches which are actuated by the hopper door flag 15. The longitudinal spacing between the caboose tripping member 16 and the caboose indicator 17 is designed to permit the caboose indicator 17 to engage the limit switch 87, and thereby de-energize the solenoid 82 and the relay 83 to lower the first part of the cam track from the raised operative position. The caboose indicator 17 then will contact and actuate the limit switch 88 to lower the second half of the cam track. As the caboose progresses between the limit switch 88 and the limit switch 89 the caboose tripping member 16 positioned on the forward end of the caboose will engage the limit switch 91 and open the normally closed contact 91a. The caboose tripping member 16 is designed to engage the limit switch 91 prior to the caboose indicator 17 engaging the limit switch 89. By having the caboose tripping member engage the limit switch 91 and opening the normally closed contact 91a which is in series with the solenoid 82 and the relay 83, the circuit to the solenoid and relay is opened. Thus, it is noticed that when the caboose indicator 17 engages the limit switch 89 to raise the cam track by closing the switches 89a and 8%, the effect of closing the switches is nullified by the prior opening of the Contact 91a which has deenergized the solenoid 82 and the relay 83 to render any further lifting of the. cam impossible. The caboose tripping member 16 in engaging and holding open the limit switches 91 and 92 until the caboose indicator 17 has passed by the switches 89, retains the cam tracks inoperative as the caboose passes over.

The caboose indicator 16 then engages the limit switch 93 illustrated schematically at the upper left portion of the schematic diagram in FIG. 3a and is shown with its associated circuitry in greater detail at the bottom portion of the same diagram. The limit switch 93 has been transposed from its position relative to the other limit switches for purposes of clarity and to facilitate the explanation. As illustrated, the limit switch 93 is actuated by the caboose tripping member 16 and includes a pair of contacts 93a, a normally closed contact, and 9312, a normally open contact. It is also noticed that the caboose tripping member 16 in engaging the limit switch 93 will open the contact 93a which is in series with the door locking cam limit switch 86 and its associated lifter to thereby remove the lifter from an engagement position at trackside. Also, when the limit switch 93 is actuated by the caboose tripping member 16 the normally open contact 93b will be closed temporarily thereby energizing the coil 95b of the mechanically latched relay 95. In pulsing the coil 95b the contact 950 will be open, thereby de-energizing the closing portion of the control system at the upper left hand portion of FIG. 3a.

At this juncture the unit train has passed the hopper car discharge area and the locomotive tripping member 14, the caboose tripping member 16, and the caboose indicator 17 may be moved from projecting outwardly of the train.

The foregoing description and drawings merely explain and illustrate the invention and the invention is not limited thereto, except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

What is claimed is:

1. A control device for regulating the discharge of lading from a train riding on tracks wherein the train has a locomotive car and a caboose car and hopper cars each with discharge door means including a door operating mechanism, said locomotive car, caboose car and hopper cars including car mounted switch actuating means to actuate trackside switch means, said control device including:

a trackside mounted hopper door operating means engageable with the car mounted hopper discharge door operating mechanism to open and close said discharge doors;

a lading discharge area adjacent the tracks and having a beginning portion and an end portion;

a first trackside mounted switch means responsive to the locomotive mounted switch actuating means;

said hopper car mounted switch actuating means operable in response to opening movement of an associated hopper discharge door;

second trackside mounted switch means responsive to both the hopper car mounted switch actuating means and to the caboose mounted switch actuating means;

third trackside mounted switch means responsive to the caboose mounted switch actuating means;

an electric circuit including the aforesaid first,

second and third trackside switch means and including solenoid means;

a hydraulic circuit including valve means operatively coupled with solenoid means of the electric circuit and said solenoid means selectively actuated by operation of the associated first, second and third trackside switch means;

said car mounted switch actuating means selectively operating the associated trackside switch means to actuate the associated trackside mounted door operating means for selective opening of the hopper discharge doors.

2. The invention according to claim 1, and

a speed control means in said electric circuit responsive to train speed and operative to deactivate said trackside mounted door operating device upon approach of the train above a preselected velocity.

3. The invention according to claim 1, and

lading depth sensing devices mounted adjacent said lading discharge area to sense lading buildup and signal the trackside mounted door operating means to prevent opening of said discharge doors to prevent discharge oflading in the builtup area.

4. The invention according to claim 1, and:

said trackside mounted hopper door operating means including a discharge door opening means positioned at the beginning of the lading discharge area and a discharge door closing means positioned at end of said discharge area;

said door operating means having cam track portions vertically movable between said tracks;

said discharge door closing means having cam track portions vertically movable between said tracks.

5. The invention according to claim 1, and

a link pivotally attached to said hopper discharge door means;

a slide member operatively connected to said link member and movable outwardly of the hopper car upon opening movement of said discharge doors to engage the hopper car mounted switch actuating means and move same outwardly of the hopper car for engagement with said second trackside mounted switch means.

6. The invention according to claim I, and

said first, said second, and said third trackside mounted switch means each including a pivoted arm member adjacent the track.

7. The invention according to claim 1, and

a door operating mechanism locking member positioned on said hopper car;

a ground mounted first cam member engageable with said locking member to thereby unlock the discharge door operating mechanism; I

a second ground mounted cam member engageable with said locking member to thereby lock the discharge door operating mechanism.

8. The invention according to claim 4, and said caboose mounted switch actuating means comprising a first caboose mounted switch actuating means and a second caboose mounted switch actuating means; said end portion of the lading discharge area including adjacent control switch means operable upon the hopper discharge door closing means to thereby close said discharge doors, said control switch means including: first trackside mounted control switch means including cam track operating switch means engageable by the locomotive mounted switch actuating means to thereby move said discharge door closing cam track portions into operative position to close said discharge doors; second trackside mounted control switch means having means engageable with both said hopper car mounted switch actuating means and with the caboose mounted switch actuating means; said second trackside mounted control switch means including spaced switch members; third trackside mounted control switch means having means engaging said caboose mounted switch actuating means to move the discharge door closing cam track portions from the operative to the inoperative position; said spaced switch members positioned at trackside and simultaneously operable by the hopper car mounted switch actuating means of passing hopper cars; said spaced switch members positioned at trackside and simultaneously operable by the second caboose mounted switch actuating means and the hopper door actuated indicator member of the preceding hopper car; the spaced switch members including means coupled with said hydraulic circuit to move said discharge door closing cam track portions to an operative position and also including means to move the discharge doorclosing means to an inoperative position; the spaced switch members including normally open and normally closed switching points in parallel to interpret the open and closed condition of the hopper car discharge doors to thereby move the door closing cam track portions to an inoperative position if discharge door means of an approaching hopper car are closed and move the door closing means to an operative position if the discharge door means are open. 9. The invention according to claim 4, and said discharge door closing means including a vertically movable cam track having a first cam portion and a second cam portion. 10. The invention according to claim 5, and the hopper door actuated indicator member including angled and rounded edge portions. 1 l. The invention according to claim 6, and said pivoted arm member including a roller portion engageable with the associated train mounted switch actuating means. 12. The invention according to claim 7, and said first and said second ground mounted cam members including associated hydraulic control means operatively connected thereto.-

13. The invention according to claim 7, and

said first trackside mounted control switch means including a cam member operating switch means engageable with the locomotive mounted switch actuating means;

said first ground mounted cam member positioned at the beginning of the lading discharge area and said second ground mounted cam member positioned at the end of the lading discharge area;

hydraulic cylinder means operatively connected with the first and with the second ground mounted cam members and actuated by the cam member operating switch means.

14. The invention according to claim 7, and

said first cam member and said second cam member being positioned between said rails and movable vertically to engage the door mechanism locking member.

15. The invention according to claim 8, and

said trackside mounted control switch means comprising trackside limit switch members;

a solenoid valve means operatively connected with said trackside limit switch members;

hydraulic cylinder means operatively connected with the solenoid valve means and with the cam track portions to thereby control raising and lowering of said cam track portions by operation of the limit switch members.

16. The invention according to claim 8, and

hydraulic cylinder means operatively connected to the cam track portions;

solenoid valve means operatively connected with the hydraulic cylinder means;

said spaced switch members including a first circuit portion having a normally closed contact and a normally open contact in parallel and a second circuit portion having a second normally open contact and a third normally open contact and a relay latching contact in parallel;

said first circuit portion in series with the second circuit portion.

17. The invention according to claim 16, and

an associated electromagnetic relay in series with said normally open relay latching contact to close said latching contact and thereby seize said relay in the operated position.

18. The invention according to claim 16, and

each spaced switch member including first and second limit switch operatively connected to and controlling operation of an associated portion of the cam track.

19. A control device for regulating the discharge of lading from a unit train of hopper cars having discharge door means and including:

ground mounted switch means responsive to passage of said unit train;

ground mounted discharge door actuating means having a hopper door opening portion and having a hopper door closing portion; trackside means actuated by the passing unit train to produce a signal for actuating said ground mounted discharge door actuating means;

means to sense a selected depth of discharged lading and signal the ground mounted discharge door actuating means to prevent hopper door opening and further lading discharge; safety means operable by said unit tram to control off train mounted discharge door actuating means to prevent actuation of the hopper door closing portion on a hopper car having unopened discharge doors.

20. The invention according to claim 19, and

said control device including speed responsive control means operable by approach of the unit train above a preselected velocity to de-energize the control device.

. 21. The invention according to claim 19, and

said control device including an electric circuit and a hydraulic circuit;

said electric circuit operatively connected with said off train mounted actuating means;

the hydraulic circuit including solenoid means and valve means operatively connected with electric circuit;

said solenoid means activated by the off train switch means to control operation of the off train mounted discharge door actuating means for controlled opening and closing of the discharge doors.

22. The invention according to claim 19, and

said safety means including spaced switch members including a first circuit portion having a normally closed contract means and a first normally open contact means in parallel and including a second circuit portion having a second normally open contact, a third normally open contact and a normally open relay latching contact in parallel;

the first circuit portion in series with the second circuit portion.

23. A control device for regulating the discharge of lading from a train having hopper cars with discharge doors, said control device including:

train mounted tripping means;

trackside mounted switch means operable in response to train mounted tripping means;

a trackside mounted discharge door opening and closing device;

hydraulic means operatively connected with said door opening and closing device; said trackside mounted switch means operatively connected with said hydraulic means for controlled and selective operation of the discharge door opening and closing device;

a trackside lading discharge area having a beginning portion including door opening mechanism and having an end portion including a discharge door closing mechanism;

safety control means operable by the train mounted tripping means to prevent actuation of the discharge door closing device when an adjacent hopper car has unopened discharge doors.

Claims

1. A control device for regulating the discharge of lading from a train riding on tracks wherein the train has a locomotive car and a caboose car and hopper cars each with discharge door means including a door operating mechanism, said locomotive car, caboose car and hopper cars including car mounted switch actuating means to actuate trackside switch means, said control device including: a trackside mounted hopper door operating means engageable with the car mounted hopper discharge door operating mechanism to open and close said discharge doors; a lading discharge area adjacent the tracks and having a beginning portion and an end portion; a first trackside mounted switch means responsive to the locomotive mounted switch actuating means; said hopper car mounted switch actuating means operable in response to opening movement of an associated hopper discharge door; second trackside mounted switch means responsive to both the hopper car mounted switch actuating means and to the caboose mounted switch actuating means; third trackside mounted switch means responsive to the caboose mounted switch actuating means; an electric circuit including the aforesaid first, second and third trackside switch means and including solenoid means; a hydraulic circuit including valve means operatively coupled with solenoid means of the electric circuit and said solenoid means selectively actuated by operation of the associated first, second and third trackside switch means; said car mounted switch actuating means selectively operating the associated trackside switch means to actuate the associated trackside mounted door operating means for selective opening of the hopper discharge doors.

2. The invention according to claim 1, and a speed control means in said electric circuit responsive to train speed and operative to deactivate said trackside mounted door operating device upon approach of the train above a preselected velocity.

3. The invention according to claim 1, and lading depth sensing devices mounted adjacent said lading discharge area to sense lading buildup and signal the trackside mounted door operating means to prevent opening of said discharge doors to prevent discharge of lading in the builtup area.

4. The invention according to claim 1, and: said trackside mounted hopper door operating means including a discharge door opening means positioned at the beginning of the lading discharge area and a discharge door closing means positioned At end of said discharge area; said door operating means having cam track portions vertically movable between said tracks; said discharge door closing means having cam track portions vertically movable between said tracks.

5. The invention according to claim 1, and a link pivotally attached to said hopper discharge door means; a slide member operatively connected to said link member and movable outwardly of the hopper car upon opening movement of said discharge doors to engage the hopper car mounted switch actuating means and move same outwardly of the hopper car for engagement with said second trackside mounted switch means.

6. The invention according to claim 1, and said first, said second, and said third trackside mounted switch means each including a pivoted arm member adjacent the track.

7. The invention according to claim 1, and a door operating mechanism locking member positioned on said hopper car; a ground mounted first cam member engageable with said locking member to thereby unlock the discharge door operating mechanism; a second ground mounted cam member engageable with said locking member to thereby lock the discharge door operating mechanism.

8. The invention according to claim 4, and said caboose mounted switch actuating means comprising a first caboose mounted switch actuating means and a second caboose mounted switch actuating means; said end portion of the lading discharge area including adjacent control switch means operable upon the hopper discharge door closing means to thereby close said discharge doors, said control switch means including: first trackside mounted control switch means including cam track operating switch means engageable by the locomotive mounted switch actuating means to thereby move said discharge door closing cam track portions into operative position to close said discharge doors; second trackside mounted control switch means having means engageable with both said hopper car mounted switch actuating means and with the caboose mounted switch actuating means; said second trackside mounted control switch means including spaced switch members; third trackside mounted control switch means having means engaging said caboose mounted switch actuating means to move the discharge door closing cam track portions from the operative to the inoperative position; said spaced switch members positioned at trackside and simultaneously operable by the hopper car mounted switch actuating means of passing hopper cars; said spaced switch members positioned at trackside and simultaneously operable by the second caboose mounted switch actuating means and the hopper door actuated indicator member of the preceding hopper car; the spaced switch members including means coupled with said hydraulic circuit to move said discharge door closing cam track portions to an operative position and also including means to move the discharge door closing means to an inoperative position; the spaced switch members including normally open and normally closed switching points in parallel to interpret the open and closed condition of the hopper car discharge doors to thereby move the door closing cam track portions to an inoperative position if discharge door means of an approaching hopper car are closed and move the door closing means to an operative position if the discharge door means are open.

9. The invention according to claim 4, and said discharge door closing means including a vertically movable cam track having a first cam portion and a second cam portion.

10. The invention according to claim 5, and the hopper door actuated indicator member including angled and rounded edge portions.

11. The invention according to claim 6, and said pivoted arm member including a roller portion engageable with the associated train mounted switch actuating means.

12. The invention according to claim 7, and said first and said second ground mounted cam memBers including associated hydraulic control means operatively connected thereto.

13. The invention according to claim 7, and said first trackside mounted control switch means including a cam member operating switch means engageable with the locomotive mounted switch actuating means; said first ground mounted cam member positioned at the beginning of the lading discharge area and said second ground mounted cam member positioned at the end of the lading discharge area; hydraulic cylinder means operatively connected with the first and with the second ground mounted cam members and actuated by the cam member operating switch means.

14. The invention according to claim 7, and said first cam member and said second cam member being positioned between said rails and movable vertically to engage the door mechanism locking member.

15. The invention according to claim 8, and said trackside mounted control switch means comprising trackside limit switch members; a solenoid valve means operatively connected with said trackside limit switch members; hydraulic cylinder means operatively connected with the solenoid valve means and with the cam track portions to thereby control raising and lowering of said cam track portions by operation of the limit switch members.

16. The invention according to claim 8, and hydraulic cylinder means operatively connected to the cam track portions; solenoid valve means operatively connected with the hydraulic cylinder means; said spaced switch members including a first circuit portion having a normally closed contact and a normally open contact in parallel and a second circuit portion having a second normally open contact and a third normally open contact and a relay latching contact in parallel; said first circuit portion in series with the second circuit portion.

17. The invention according to claim 16, and an associated electromagnetic relay in series with said normally open relay latching contact to close said latching contact and thereby seize said relay in the operated position.

18. The invention according to claim 16, and each spaced switch member including first and second limit switch operatively connected to and controlling operation of an associated portion of the cam track.

19. A control device for regulating the discharge of lading from a unit train of hopper cars having discharge door means and including: ground mounted switch means responsive to passage of said unit train; ground mounted discharge door actuating means having a hopper door opening portion and having a hopper door closing portion; trackside means actuated by the passing unit train to produce a signal for actuating said ground mounted discharge door actuating means; means to sense a selected depth of discharged lading and signal the ground mounted discharge door actuating means to prevent hopper door opening and further lading discharge; safety means operable by said unit train to control off train mounted discharge door actuating means to prevent actuation of the hopper door closing portion on a hopper car having unopened discharge doors.

20. The invention according to claim 19, and said control device including speed responsive control means operable by approach of the unit train above a preselected velocity to de-energize the control device.

21. The invention according to claim 19, and said control device including an electric circuit and a hydraulic circuit; said electric circuit operatively connected with said off train mounted actuating means; the hydraulic circuit including solenoid means and valve means operatively connected with electric circuit; said solenoid means activated by the off train switch means to control operation of the off train mounted discharge door actuating means for controlled opening and closing of the discharge doors.

22. The invention according to claim 19, and said safety means including spaced Switch members including a first circuit portion having a normally closed contract means and a first normally open contact means in parallel and including a second circuit portion having a second normally open contact, a third normally open contact and a normally open relay latching contact in parallel; the first circuit portion in series with the second circuit portion.

23. A control device for regulating the discharge of lading from a train having hopper cars with discharge doors, said control device including: train mounted tripping means; trackside mounted switch means operable in response to train mounted tripping means; a trackside mounted discharge door opening and closing device; hydraulic means operatively connected with said door opening and closing device; said trackside mounted switch means operatively connected with said hydraulic means for controlled and selective operation of the discharge door opening and closing device; a trackside lading discharge area having a beginning portion including door opening mechanism and having an end portion including a discharge door closing mechanism; safety control means operable by the train mounted tripping means to prevent actuation of the discharge door closing device when an adjacent hopper car has unopened discharge doors.