US2441978A - Latch tripping mechanism - Google Patents

Description

4 Sheets-Sheet l Wom Q Nu hwmew awe/Mom f/VGH IA .SFA/FORO,

May 25, 1948. H. w. SANFORD I LATCH DRIPPING MECHANISM Filed Jan. 20, 1943 May 251, 1948. w, n' v 2,441,978

LATCH TRIPPING MECHANISM Filed Jan. 20, 1943 4 Sheets-Sheet 2 May 25, 1948. H/w. SANFORD 2, 8

LATCH TRIPPING' MECHANISM Filed Jan. 20, 1943 v 4 Sheets-Sheet 3 May 25, 1948. H. w. SANFORD LATCH TRIPPING MECHANISM Filed Jan. 20, 1943 4 Sheets-Sheet 4 Patented May 25, 1948 jUNlTED STATES PATENT; OFFICE v i v LATCH :rrnrrnve MECHANISM Hugh W, Sanford, Knoxville, Tenn, assignor to The Sanford Investment Company, Wilmington, Del., a corporation of Delaware. Application January 20, 1943, Serial No. 473,013

the like, particularly such as employ mine cars,

provision is made. for the automatic dumping of such conveyors by releasing the drop bottom doors when theconveyor reaches the bin or other point .ofdischarge. ,It has been customary and desirable for a series of drop bottom doors to be interconnectedfor successive droppingin 12-3 order from front to rear of the car when the car :reachesthe point of dumping,

This has been accomplished usually by supporting atiree edge of a forward door upon a hinged edge'of the; next :rearward door in such manner that the'opening .of the latter will relea'seia'utomatically theforward door for dropping. The rearmost door of thecarhasit's free edgesupported by latch means adapted to be released'when the car reaches the point of dumping.

Such automatic cars as generally used heretofore haverequired latch barmechanism located outside the car for controlling the dropping of thedoors. Such latch bar mechanism has been objectionable and expensive.

I have set forth in my prior application on Door latch mechanism, Ser. No. 432,341, Patent No. 2,399,708, improved latch mechanismsfor controlling the release of the doors. 1

, The object of this invention is to improve'the construction; of the tripping mechanism for the door; latches,ito facilitate the release of the -latches by mechanism having improved characteristics, while enclosing the latches in protected positionso'n the car.

I haveshown the invention in several modified ,iorms inthe accompanying drawings, in which:

,- 1 is a side elevation of a mine car and track, showing latches of the character here used;

; Fig. 2 is'an' enlargedside elevation-of an end portion of the car, showing one form of tripping device;

;',Fig. 3 is a diagrammatic view of aportion of -the car and showing the tripping device in one pos ion;

4.-is a similar-view showing the tripping device-in' another position 18 Claims. (01. 21458) Fig. 5 is a diagrammatic end elevation, in section therethrough; n

Fig. 6 is an end elevation of the control switch partly for the tripping device;

Fig. '7 is a side elevation thereof; and

Fig. 8 is a diagrammatic view from the side of the car showing a modified form-of tripping device. 7

The invention is shown as applied to a drop bottom mine car adapted for the conveying of coal or other loose vlading from areceiving point to a pit or other point of discharge: The mine car is shown generally ofthe type set forth, for instance, in my prior patent} No. 2,001,471, granted May 14, 1935, representing a four-wheel mine car having three drop bottom doors, adapted to travel on a track formed bya pair of rails designated generallyR .L v c The general structure of the car comprises side and end walls I and 2, respectively, the side walls I rising from a pair of oppositely disposed side sills 3 connected together at the ends of the car by means of combined end-sills and bumpers the adjacent axle 6.

' The car is shown as of thecharacterprovided with three drop bottom doors adapted for discharge in 1,-23 order from front torearof the car, which doors are designated respectively [0, II and [2, The forward door I0 is pivotally supported on a hinge rod J3, while each ofthe middle and rear doors H and, I2 is slidably and pivotally mounted. on a hinge rod l4, extending between opposed boxes,.with the extreme forward edge of said door projecting laterally from the hinge rod and arranged to support the free edge vof the next forward ,door. 7 Thus upon release of the rear door it may, drop suificient to drag and move bodily rearward, thereby'releasingithe free edge of the middle door which will likewise move downward and rearward releasing the freeedge of the forward 'door.. This occurs usually just before the car reaohesthe' bin and permits dropping of the forward, door forpdischarge of the lading as-soon as .room enough is provided in the bin therebeneath, the otherfdoors dropping in succession during forward movement of the car over the bin, in 123 order from front to rear of the car.

After dumping in passing over the bin, the doors are adapted to be closed by the usual doorclosing rails located in the track, said doors having indentations I to ride thereon, which successively-svving them into their closed positions. The doors may be pushed forward'into tightly engaged supporting positions by wedge blocks having upwardly and forwardly inclined front faces in position for. engagementhy?lugst attachedv to the free edge of the rearward door I2 and projecting therefrom, as set'forth mpre fully in my prior Patent No. 2,0013471grantedMayl l, 1935.

As shown in Figs. 1 to 5, provisioniisimadeior latching the free edge of the rearward .door .I2.

for thereby holding the. doors I0, II and"'i2'in their closed positions, retaining the lading in the ing. For this purpose latches iii are-provided adjacent the-rear end'of=the" carpivotally sup-" *Each'of the'latches-has a conoave-seat -2ll formed therein in position to engage a trunnion ZI attached to thefree edgefof-the' rearward door I2 to *support 'said' rearward "door. As shown in Fig.8; the seat 20 is located on the opposite-side of the vertical "planepassing through the axis of the'shaft I 9 from the door I2, so that the weight ':of the doorandthe' 'la'ding thereontendsto'maintain'. the"latched relation without anytendency for this "wei'ghtito "push' the l atch" to one side. This'is particularly true becauseof the concave shape of the seat 20 engagedby'theconveirend oit'he .trunnioni' I whereby-anymovementof the :latchi'tendin'gto'releasdthe door must flrst raise upthe' free 'e'dge'bf thedoor.

Each offthe ilat'ches I 8' has afl'at'eralfpin"2 2" at-- tached "theretoiaridi'projecting through a' slot- 23 in theleidjacentipor'tion of the ende'sill '4; sothatia lever can be 'insertedfove'r said sill,'beneath the pin-22; fori'the'manu'alrelease of said latch.

I "A coiled spring"245 is iinterposed'fbetween"the. finneri face .of the end 'sill 4"an'd"lthe1atchI8, tending to help'.to return; said "latch" to"'a'"posi- Lt'ion where fit'w'i'll engage and support the trunjni'o'n 2 I. The lowefforward edgeof:ieaclf"latch I 8" is .providd'with" a shoiilderi'fi tobe engaged for releasing the'latchfash'ereinafter explained.

.As shown in Figs. .2 and 3, 'thela'tches" tiliare interposed be'tween"the""ifree.v end or .theu'earward door-1'2 and-"the adjacent:eridrmFMbeneath: a "guard. p1 ate" 2;! andaretdijsposd" .vvholly' above fthe'iower edge of saidend-sillbr bumper;and also above th lowerj porti'ontfoithe'rear door inpro- ;tected positions. This. prevents"disarrangement I of theilatchesior acci'dental'finj uryith'ereto inf the :event of wreckage .ofithe 'car;:as*frequentiy :oc- "curs, thus'tinsuring adequate protection of "the latches'to maintain-the same ini'prop'erf operative -po"s'itions.

One i form ii of 'ielectri'caliy actuated trippin'g mechanism is. shown "in "Eigs."2"to"7,' in "which however,"theltri'ppingi armfiis' mounted'ffor slid-- 'ing" movement to release eachofi thexlatches l 8 whichsupport" the free-edge hf'the'door'i 1 2;

7The free edge "or the doorIIZ isfprovideidwith a shoulder 1 3I normally "disposed immediately "over 'ithe upper lend" of thetr ippingfa;rm "I 32,as shown inFigZ a -isaid upbf 'r end'of the" tripping 4 adapted to enter the space between the door and the forward edge of the latch I8 to move said latch to its released position, as shown in Fig. 4.

The tripping arm I32 is arranged vertically 5 and slidably mounted by means of rollers I 33 in 10 solenoid I 31; A coiled spring I38 acts on the "plunger I36 tending to move the latter to an ex- #:tendedposition, asshown in Fig. 5.

Current is supplied to the solenoidl31 through aflvirteliifif Roma-"gravity switch I39 which is jgu shown-asi'aizmercury switch. The switch I39 is "eonstructed in the usual manner of a tubular 'fbodywoffinsulatingmaterial enclosing a pool of mercuric. and having a pair of contacts at one "endp'ortion of the switch body which have electrical connection through the pool of mercury car until the latching means is released for dump- V 'whenithe bodyrlis tilted-iimione directionmszshuwn 'linl i'gs'z3lande lrbuteareroutzoft electriealecon ion l with achcoth'er 'wh'emthe switcliziisetiltd insanotheridirectionIasrslititvninfi'ig.1J7.

I Thimercluliyisiiiitch I-ISBiissupportEdbyEamarm tee pivotallym-ounted onaa shaft iflafidprevidd with a counterweight- 1 flwhibi'tinormallyractsito move the arml Hmtoiits lowered position'yasvshuwn iull linesiim'Fig: 7,i:whereztthezeounterweight .1 r I 42 2 stops:theLfdownwam.swmgingim'ovementlhy thelan'gular portionzifizz'thereoi. ii'rhe sher MAI :i-s'supperted abeaningebox '14 ipand .a'lsmhas mounted? thereon an :a'ctuatingearm at: l lii'which has -a shouldered: connectionfwith theiiarm Hi0,

so. as to "lifttthe latteriiarmr'irometh'e'izpositlon showna inEF F-igfi' 'htoithe position fshownzinim'gss ii 'and e, while the actuatingxarmi-MS s'irnevertheless free for movement'relativtotitheiarm flw to the: dottediline position:mfi Eig.1 7. :Z'Iheaarmflfl e *haslan" o'ii staridiri zioracket fiiconnected therewilth from whichia counterweight 'lflaissusperided tozreturn the actuatingjza'mn fl mmmzthefposition shown'f in "dotted ilinesizinisEig; II, to'i'thefiullrime zpositiorrtherein.

= when the -actuating arm ii isi-engagdzhvithe lug' fl on -the ibo'ttom of th'e' ear -sidesillfiarfd is moved thereby from the full line positionin lil'g. 7, -which is its normal position asdescribed to the position shown in -Fig. 3. ""l his cemse the poorer-mercury to' be tiited into en'gag'emen with the contacts in the 's'vv itch,=' blosing theelectmc circuit through the Wire-138 i'tci the@sb1enoid 1I1, 'energizingg the' latter. IIhe oppositeiiside bfkm S'Wit'ch IBQ aridnof the "so1eneidare connec d to '55 "any suitable oridesirable source of electriehl iiurrent sufii-cient to -actuate the sele'neid. "i'rheienergizingof t-he' solenoid W31" retracts theiphmger 136 against the tension 'f the spring wee-wed "slides -the"trippingarmfli,i upwarkily; lid- 'ingmovementzofsaid 'trippinggrm-isstoppe by -7 the actuating arm, the counterweight I 42 i"tncns said arm-:to its normal uptightcposition: as shown in Figs-'1. "iihis imm'ediately breaks' ithe eireiiit at the switch and deenergizes the solenoid fll, allowingthe spring] 38 to move the tripping arm am- 132 isshown'as substantially"-we'dge shaped 76 I32 to its lowered positiomiFigi )Fwhere ifiis door.

It will be noted that the wedging enact the arm I32 is so sloped thatthere will be no tendency for the engagement thereof by the latch I8'to push the arm I32 downward against the force of the solenoid. Therefore, the only required function of the solenoid is to raise the tripping arm up to its operating position at the proper time, and to permit it to be lowered at the proper time,lwhere the latch has beenreleased and before the end-sill strikes the upper end of the tripping arm.

When the car moves over the tripping mechanism in the reverse direction, the lug 41 will engage the actuating arm I45 and. move it to the dotted line position in Fig. '7, but such movement is relative to the arm I40 carrying the mercury switch, and therefore the circuit is not closed through the'switch. Thus the reverse movement of the car does not cause a raising movement of the tripping arm I32.

- The design illustrated has provision for supporting the free edge of the door by two latches on respectively opposite sides of the center line of the car, and each arranged for release by a solenoid-actuated tripping arm. However, if desired, the construction may utilize one solenoid for actuating two separate. tripping arms, and if two separate solenoids be provided, both of those may be controlled from a single switch.

The circuit controller shown in Fig. 8 may be substituted for that shown in Fig. 3, if desired, or vice versa, inasmuch as each controls the operatlonof a solenoid, and may be used to control the operation of either type of tripping arm.

It will be obvious also that the tripping arm may be actuated pneumatically, instead of by the electrical solenoid, by connecting the piston of a of the end sill structure and the bottom of thedoor.

that the latch hooks do not project below the bumper sill and are protected between the bottom door and the bumper sill in such'fashion that they will not be interfered with by obstructions on the track. All of the different devices likewise provide for raising the unlatching arm so that it will come'up to the point of engaging the hooks for unlatching at .the proper time and without contact with the normal drop bottom door and without possible contact with the end sill. The release of the unlatching mechanism always takes place in time to permit it to drop away from the latch hooks themselves immediately after these latch hooks have been rotated around the pivot far enough to release the latch hooks from their supporting engagement with the drop bottom door.

In the form shown in Fig. 8, a tripping arm 95 has a head 96 in position to be moved into engagement with a forward face of thedoor supporting latch I8b which normally supports, the free edge of the doorIZb by means of a trunnion m, as described above. Thetripping arm .95 is All of the different forms embody the feature pivotally supported at 91 on a bracket 98, and has a counterweight 99 on the opposite end thereof from the head 96. This counterweight 99 reduces the amount of power required to'raise the tripping arm 95, but does not prevent it from falling promptly when released. 1

The tripping arm has a shoulder I00 in position for engagement by a wedge I04 carried at the forward end of a member I02, slidably mounted upon rollers I03 within a guide member I04. The guide I04 has a .slot I05 in the under side thereof through which an arm I06 projects, which arm is rigidly formed on the wedge member I02. The arm I06 is pivotally connected at I01 with a plunger I08 on an electrical solenoid I09. A coiled spring H0 is sleeved over the plunger I08 and has a bearing engagement therewith at its outer end at III, tending to move the. plunger in an outer direction relative to the solenoid I09. 7

The solenoid is controlled by a switch which is actuated by ,a shoe 2 in position for engagement with a lug 41b secured to the under face of the side sill of the car as described. The

shoe H2 is secured to a sleeve II3 slidably connected at H4 with a rocker member H5 which is pivotally supported at MB.

A coiled spring I I1 is housed within the sleeve I I3 and tends to extend the shoe I.I2 relative .to the rocker member I I5. The rocker member I I5 is free to turn in a clockwise direction .in'Fig. 8 about the pivot '6, but has its movement in the opposite direction limited by an arm I I8 adapted toengage a rigid stop I I9 mounted in a fixed position beneath the track. A spring I20 is connected between the rocker member I I5 and a stationary anchor I2 I, tending to restore the rocker member and the shoe I I2 to a central position, as shown, if moved out of said position.

The sleeve I I3 has an arm I22 projecting laterally therefrom and supporting a plunger I23 sliclably mounted therein through an insulatingbushing I24. A coiled spring I25 tends to move the plunger 123 in one direction. The free end of the plunger I23 carries a contact I26 in position to engage a contact I21 secured to the rocker member H5 but insulated therefrom. The contact I 21 is connected through a wire I28 with the solenoid I09. The contact I26 and opposite side of the solenoid coil may be connected with a track circuit, or other source of electrical supply through suitable connections as shown, adapted toenergize the solenoid upon the closing of the switch I26I2'I.

When the shoe H2 is engaged by the lug 41b and depressed, this will close the contacts I26, I21, sufficiently to energize the solenoid I09. When the solenoid is thus energized, the plunger I08 is moved to the right in Fig. 8, thereby moving the wedge I M to its dotted line position, pressing upward on the shoulder I00 and raising the tripping arm 95 to the dotted line position illustrated. This moves the head 96 in position to engage the forward face of the latch I81) upon v further forward movement of the car to release the door for dropping. As soon as the lug 41b passes over the shoe H2 the latter is raised by the spring I I! disengaging the contacts I26, I21, which causes deenergizing of the solenoid coil I09. This allows the spring I I0 to move the Wedge I0=I back to the full line position, and allowing the tripping arm 5 to be lowered out of the path of the latch I82), and the end sill of the car, for dumping of the doors in the manner desc i d a e.

when the car moves over. theadumpingjbin .and

the tripping mechanism in .a reverse direction (toward the right .in Fig. 28).,=the shoe zlzl2i'will' be .rotatedtoward the right bysth'e engagement of the lug 41b. The switch will :rotate with the shoe since it is carried by :therocker member 1:15.

and will not be closedbyrthis rotary..movement becauseof the lackofmovementlof the shoe H2 and its. sleeve ll.3':relative to therocker member H 5. Thus the. solenoid vH39 :Will .not the energized to raise the tripping arm .35. After 'the-ca-r-tth-us. passes over the tripping mechanism. in the reversedirection described,- the spring I will :return the shoe H2 to its vertical position, where-:it-is heldby the stop l H). 7

As described above, oneor more latches may be used for supporting the :free edge ofthe door, and, if desired, the tripping arm 95 maybe provided for each latch. Gne solenoid could be-used,

if desired, to operate several tripping arms which correspond with the respective latches, or separate solenoids provided for the respective'trip ping arms, all of which may be controlled from a single switch orshoe.

I claim:

1. In conveying mechanism, the combination.

with a trackway, a dumping vehicle mounted on the trackway and including-a frame-structure having a drop bottom dumping door,-and latch means for holding the door closedand movable to release said door for'dropping o-f tripping mechanism mounted at the trackwayfor upward movement relative theretoin position -to-actuate the latch means, said tripping mechanism including an actuating armhaving an end-portion in position for engaging the latchmeansto release :the same, means mounting-said tripping arm for sliding movement, electro-magnet-ic means for actuating said arm, switch means -forcontrolling said electro-magnetic means, and swinga-ble means actuated in-responseto .movernent of the dumping vehicle to apredetermined position for operating said switch means;

2;.In conveying mechanism, latchtripping" mechanism adapted to be mounted ata track- Way to release latch mean's of a drop'b'cttom door, said latch tripping mechanismcomprising atripping member, means mounting said member fortro-magnetic means,and swingable means'adapted to be actuatedby movement of a vehicle-along the trackway for operating said switch -means;

'3. In conveying mechanism,--thecombination with a trackway, a dumpingconveyance "movable along the trackway and'including a frame structure having transverse-end-sil-l structure-and having a lading body with a drop bottom-=door,

veyance, of tripping mechanism including means' mounted at the trackway andmovable to-release' the latch means, electrically actuated means operatively connected with the latch release-means for .movingihe:latch'tripping. mechanism ;to=-en-. gaging position, and means actuated in response.-

tomovementrof the dumping conveyance torazpredeterminedrpositionionwthe. trackway-for controlling engaging of: :the. electrically-actuated means.

.41.;Inconveyingalmeohanism, the combination:

withsagtraokwayya, dumping conveyance movable alon'gzthe :trackwayland including .aframe. struce tur'eahavingatransverse. end-sill structure, and; having..;.a aladingbodyzwith a..drop bottom "door; latch-means :ifor holding the door in c'losed posi:

tion and movable to release the door for opening, said-latch :means being :located wholly above I the lowestcportion" of. the end-sill .:structure in the:

same longitudinal rvertical plane. of :the conveyanon, eof- 'tripping..imechanismincluding 'means mounted. at .the. track-way andmovable to release.

the-.;.lateh :means, electrically actuated means vmounted:atrthe trackwayin :positi'onuto begd-is.

posed-directly undertthe-drop bottom. door when the dumping conveyance passesxthereoversand.

connected WithiSdid latch:relea's ermeanssfor moving;;.the latch-tripping :mechanism to. engaging position,. (and means for controlling "the :action or the :-;e1ectrically-actuated means; and operated by thermovement of z the dumping; conveyance thereoven; 5:111conveying mechanism; the combination wit-ha trackway aidumping sconveyance-movable along the trac'lewayrand including.rasfram-e-struoturcrhaving transverse:endesillstmcture and having; a .ladingbody .with-za'drop "bottom door, latch" means .forszholdingl: :thQidflOI' in closed position it and: .movableto release the. door. for opening, .of

tripping mechanism :including. means mounted at :thetraokwayand movable into operatingrrelation with, the Jatchrmeans, andreleotro-magnetic means mounted attt-he ,trackway imposition :to be disposed: directly, under the'rdrop bottom: door when the; dumping-conveyance is :rpassing -th"ere- J over: and .oneratively. connected-with the 'tI'iIJ- pingmeans forymoving said tripping -.means into operativerelatiomrwith lithe latch; means to. reeafic-rrtheedoor; and means; for zzontrolling. the

actiona-of the -electroamagnetic mean's and op.-'

erated by the movement zo'f the dumping conveyancethereover.

i6l' Int-conveying:mechanism, the. combination with a'itrackway, agdmnpingcconveyance movable along the trackway and including a frame structluichayingttransverse endsillstructureand havinga ilatiinglrbodyswith-a .drop.:.bottom door, latch meansifor holding the door in-clos'edpositionand movable 1120. release the zdoor for opening, .said

latclrmeans:beingilocated wholly aboveithelowest Dortionpf Zthfirifll'lidrfifllitlllfltlfl' inthelsame {Ion-- giitudinal;verticalizplane zofithjel-conveyance, of trinping::.mechanism ,i-rrcluding. T means mounted at 'ithelwtrackway iandimovablefinto aactuating en-' gagement with'ihe datchzmeans, electro-magneticmeans connected iwithisai'dlatch actuating means fiommovingzth'eilatch actuatingmeans .to engag;

ingrpositi'on; andar'rreans actuated in response/to movement zof. .afdumping. conveyance 'ior. icontrol'ling the eleotroemagneticmieans;

1'7... Fln gconveying :;mechanism,. the combinationwith axtrackway,a dumpingrconveyance movabl v tion and movablaftoreleasegthe 'door for-openingy oi tripping meohanismeinoluding means mounted at the trachwayiand-movable into operating relation with the latch means, electro-magnetic means for moving said tripping means into operative relation with the latch means to release the door and a switch electrically connected with said electro-magnetic means and having operating means therefor in position for operation by the movement of the dumping conveyance along the trackway to a predetermined position relative thereto.

8. In conveying mechanism, the combination with a trackway, a dumping conveyance movablealong the trackway and including a frame structure having transverse end-sill structure and having a lading body with a drop bottom door, latch means for holding the door'in closed position and movable to release the door for opening, of tripping mechanism including means mounted at the trackway and movable into operating relation with the latch means, power'means constructed foroperation by a source of power externally of the conveyance itself and mounted at'the trackway for moving the tripping means into operative relation with the latch means causing release of the door for dropping, and meansfor controlling the action of said power means and operated by the movement of the dumping conveyance to a predetermined position in the trackway.

9. In conveying mechanism, the combination with atrackway, a dumping conveyance movable along the trackway and including a frame structure having transverse end-sill structure and having a lading body with a drop bottom door, latch means for holding the door in closed position and movable to release the door ior opening, of tripping mechanism including means mounted at the trackway and movable into operating relation with the latch means, power means constructed for operation by a source of power externally of the conveyance itself and mounted at the trackway for moving the tripping means into operative relation with the latch means causing release of the door for. dropping, and means actuated in response tomovement of the dumping conveyance to a predetermined position on the trackway for controlling said actuation of the power means.

10. In conveying mechanism, the combination with a. trackway, a dumping conveyance movable along the trackway and including a frame structure having transverse end-sill structure and having a lading body with a drop bottom door, latch means for holding the door in closed position and movable to release the door for opening, said latch means being located wholly above the lowest portion of the end-sill structure in the same longitudinal vertical plane of the conveyance, of tripping mechanism including means mounted at the trackway and movable to release the latch means, electrically actuated means for moving the latch tripping mechanism to engaging position, and means actuated in response to movement of the dumping conveyance to a predetermined position on the trackway for causing energizing of said electrically actuated means and movement of said latch tripping mechanism.

11. In conveying mechanism, the combination with a trackway adapted to receive thereon a dumping conveyance for movement along the trackway and having a drop bottom door with latch means for holding the door closed and movable to release the door for dropping, of tripping mechanism including means mounted at the trackway for movement into operative relation with the latch means to release said latch means,

and electro-magnetic means connected with the latch tripping means for moving the tripping means into said operating position, and a. switch electrically connected with said electro-magnetic means and having operating means therefor in position for operation by the movement of the dumping conveyance along the trackway to a predetermined position relative thereto.

12. In conveying mechanism, the combination with a trackway adapted to receive thereon a dumping conveyance for movement along the trackway and having a drop bottom door with latch means for holding the door closed and movable to release the door for dropping, of tripping mechanism including means mountedat the trackway for movement into operative relation with the latch means to release said latch means, and electro-magnetic means connected with the latch tripping means. for moving the tripping means into said operating position, and means in position for actuation in response to movement of the dumpingconveyance to a predetermined position on the trackwayfor causing said actuation of the electro-magnetic means.

.13. In conveying mechanism, the combination with a trackway adapted to receive thereon a dumping conveyancefor movement along the trackway and having a drop bottom door with latch means for holding the door closed and movable to release the door for dropping, of tripping mechanism including means mounted at the trackway for movement into operative relation with the latch means to release said latch means, power means constructed for operation .by .a source of power externally of the conveyance itself mounted at the trackway connected with the latch tripping means, for causing said movement of the tripping means to a latch releasing position, and means for controlling the action of said power means and operated by the movement of the dumping conveyance to a predetermined position in the trackway. H

14. In conveying mechanism, the combination with a trackway adapted to receive thereon a dumping conveyance for movement alongthe trackway and having a drop'bottom door with latch means for holding the door closed and movable to release the door for dropping, of tripping mechanism including means mounted at the trackway for movement into operative relation with the latch means to release said latch means, and power means mounted at the trackway connected with the latch tripping means, for causing said movement of the tripping means to a latch releasing position, and means mounted at the trackway in position for actuation by the dumping conveyance when moved to a predetermined position on the trackway for controlling said actuation of the power means.

15. In conveying mechanism, the combination with a trackway, a, dumping conveyance movable along the trackway and including a frame structure having transverse end-sill structure and having a lading body with a drop bottom door, latch means for holding the door in closed position and movable to release the door for opening, of tripping mechanism including means mounted at the trackway and movable into operating relation with the latch means, and power means mounted at the trackway operatively connected with said movable means for moving the tripping means into operative relation with the latch means causing release of the door for dropping, and means actuated by the dumping conveyance in response to movement of the tripping meehanism including means mounted at t'lie"traokway I and movable; to. release the latch =means, electrically actuated meansoperatively 'conneoted'-Withsaid movable meansfor moving I the latch tripping mechanism; to: engaging position ,--and means mounted for-swinging: movement lengthwise: of; the trackway -and constructed for V circuit: closing action upon movement'in one direction only relative thereto-1andiactuatedl by the dumping-conveyance: in; responseto .movement off the: dumping conveyance. to: a. predetermined 1 position on: the .trackway; said circuit .olosing means: bein g v electrically connected. .wvitlrthe: electrically actuatedfmeans for: causing energizing: of said: electrically. actuated tmeans and. movement oi'lsai'd latchtrippinamechanismaupon:saidzmorvement; of. thez'sald circuit: closing; me ans.

:17; i Inrconveying: mechanism; the: combination of atnaokwayadaptedto receive th'ereonia dumping conveyance for movement along the :trackway and havinmardropbottom door' latch means: for holding thei'doort closed and movable to release the door foridroppin'g', tripping mechanismi includingmeans mounted. at. the trackway "formovement: into -operative relation with? the a latch means to release said latcl'r m'eans, electromagnetic means operatively-xconnected with said tripping means forzmoving the. tripping, means intosaidi operating position; and means in posi- 1 tion'; for: actuation by; the-:dumping conveyance f im'response to movement of the cluinping? convey- Number" V ancerinvone directionronly toaipredeterminedzposition: on; the: trackwayfionrcausing said-actuation of: the ..electro-magnetic'means.

18. 'In. conveyingcmechanism;theecombination of a t-rackwayaadaptedto-receivathereonia.dumping": conveyance. tor; movement; along the trackwayand having. a dro bottom: doorwit'h. latch means for holding-the door closeda-nd-movable to release the door for dropping, trippingfimechanismincluding. means, mounted: at; thentnackway for. movement into operative relation; with; the

latch means -,t0"'1:e1ease latch; meansyaand power means. mounted at: the trackwayr'andzxoperatively connected'ewithp saidlatohreleaseimeans for causing saidpmovement;of:.the-trippingrmeans toalatch releasing position, andmeansamountd at the trackway: in position: for actuation: by'the dumping: conveyance when: moved? in ,oneasdirection only to. a predetermined:rposition'onazthe trackvvay for-causing? said; actuation of, the power means. l l GH- W. -SANFQRD;

. V ,REEERENCES ormn The followingreferencesare "of''- record in" the file of this-patentr r UNITED STATES PATENTS.

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