US2600357A - Apparatus for closing dump car doors - Google Patents

Description

J1me 1952 c. E. ZIMMERMAN APPARATUS FOR CLOSING DUMP CAR DOORS 2 SHEETS-SHEET 1 Filed Feb. 11, 1950 FIG. I

FIG. 2

a INVENTOR 1! 4r a: .Z'mmmmn ATTORNEYS June 10, 1952 c, E. ZIMMERMAN APPARATUS FOR CLOSING DUMP CAR DOORS 2 SHEETS SHEET 2 Filed Feb. 11 1950 I W M ATTORNEYS W mm a M m Patented June 10, 1952 APPARATUS FOR CLOSING DUMP CAR DOORS Charles E. Zimmerman, Globe, Ariz., assignor to Inspiration Consolidated Copper Company, a

corporation of Maine Application February 11, 1950, Serial No. 143,615

7 Claims. 1

This invention relates to apparatus for closing the discharge doors of bottom-dump ore cars. More particularly the invention is concerned with a fluid-operated apparatus designed to replace the manually operated mechanism ordinarily provided for closing the doors of such dump cars.

Heretofore, after the doors of a bottom opening dump car have been opened to discharge ore carried by the car, it has been necessary, in order to close the doors, to manually operate a crank mechanism which raises the doors to closed position. The doors must then be maintained by the crank mechanism in the closed position until a latching mechanism, secured to the dump car, may be operated to lock the doors in such closed position. Because of the weight of the doors for an ordinary dump car, the manual closing requires considerable labor, is slow and tedious, and is not altogether safe. Additionally, in order to speed up the use of the manually operable closing mechanism, two men must be employed, one to operate the closing mechanism and another to operate the latching mechanism for locking the doors in closed position after the closing mechanism has been operated.

It is the object of this in vention to provide a fluid-operated mechanism to take the place of the former manually operated mechanism and to accomplish the closing of the doors of a dump car quickly, safely and without the tedious and laborious manual effort that has heretofore been required. The invention contemplates the accomplishment of this object by a fluid-operated mechanism controlled entirely by a single valve means. The fluid-operated mechanism contemplated provides an equal closing force for each door of the dump car, whereby each door may be fully closed despite any resistance to closing encountered by another door. Furthermore, the fluid-operated mechanism for closing the doors includes a time-delay device, whereby the doors are automatically held in closed position for a predetermined period of time before the fluid-operated mechanism ceases to exert the closing forces on them so that the door latching means carried by the car may be operated to lock the doors in closed position safely and without any danger to the operator.

Briefly, the fluid-operated mechanism for closing the doors of a bottom-dump ore car comprises a pressure-tight cylinder mounted on the center sills of the car and provided with fluid under pressure through an opening in its lower end. A reciprocable piston, supporting an upwardly extending piston rod, is mounted in the cylinder and adapted to be moved upwardly under the pressure of fluid supplied to the cylinder. A sheave or pulley is attached to the upper end of the piston rod and freely supports a cable, the

opposite ends of which. are connected to the car doors. Upon the admission of fluid under pressure to the cylinder the piston, piston rod, and} pulley are moved upwardly, thereby drawing the cable upwardly, and as the cable is freely supported by the pulley, equal forces are provided to the car doors to urge them closed. The flowof fluid to and from the pressure-tight cylinder is controlled by a valve operable in one direction to permit the flow of fluid to the cylinder and in the opposite direction to permit the flow of fluid from the cylinder. The valve is so designed that it is normally urged in the latter direction. However, a latching mechanism is additionally provided whereby its operating handle may be main,-

tained in the position in which the valve is operable to supply fluid to the cylinder. A time-delay device is associated with the operating handle of the valve to unlatch it after a predetermined interval and permit the valve to return to a position in which fluid already supplied to the pressure-tight cylinder may flow through it from, or out of, the cylinder. The time-delay device is operable in response to the position of the piston in the cylinder and/or in response to the volume and pressure of the fluid supplied to the pressuretight cylinder, and is actuated when the piston has been moved upwardly in the cylinder to the position at which it lies when the car doors are closed. The period between this time and that at which the time-delay device has effectively acted to unlatch the valve-operating handle thereby releasing the fluid from the elevating cylinder is sufliciently long to permit the operation of the latching means by which the doors of the car may be permanently maintained in closed position.

For a more detailed description of one type of apparatus which falls within the scope of this invention, reference may be made to the accompanying drawings in which:

Fig. 1 is a perspective View of a bottom-dump ore car provided with a fluid-operated door closing mechanism according to my invention,

Fig. 2 is an end view of the car shown in Fig. 1 in which parts of the car are shown in section in order that my novel closing device may be seen more clearly,

Fig. 3 is a sectional View taken along line 3-3 of Fig. 2 and shows the cable raising mechanism and time-delay device,

Fig. 4 is a sectional view taken along line 4-'4 of Fig. 2 and shows, in detail, the valve mechanism employed for controlling the flow of fluid to and from the door closing mechanism, and

Fig. 5 is a sectional view taken along line 55 of Fig. 2 showing more clearly the structure of the upper end of the cable-carrying piston rod and the guides therefor.

By reference to Figs. 1 and 2, a bottom opening dump car, and features thereof that are old, will first be described. The dump car has upright side walls 2 and sloping end walls 3, only one of each of which may be seen in the drawings. The bottom of the car is partially formed by downwardly opening doors 4 and 4' (Fig. 2)

partially supported by shafts 5 and 6, which The extend throughout the length of the car. remainder of the bottom is formed by a longitudinally extending fixed member or members) 1, which is triangular in cross-section so as to direct the car contents through the doors when the latter are opened by being pivoted downwardly about shafts 5 and 6. The car is adapted to be supported on railway rails 8 and 9 by a four-wheel truck at each of its ends, only oiie'truck being shown in the drawings. Each of the doors 4 and 4' is supported bya'plurality ofhinges ll secured to the underside of the doors at spaced intervals along their longitudinal extent. The inner end of each hinge is formed with a loop [2, which is adapted to surround the longitudinally extending shaft or 6 and to therebysupport the inner end of the hinge and inner edge'of the door. Each hinge i l is of sufficient length to extend a short distance beyond an outer side wall 2 of the car when it supports a door in closed position. Door latches 13, one for each door hinge, are pivotally supported by pins M on the outer face of side sills l5 of the car; Connecting rods it, one for each side of the car, connect the upper ends of the latches and are themselves connected by a transversely extending rod I! by which all the latches on the car may be pivoted or operated from one posi-, tion. The lower ends of the latches have projecting portions l8 which are adapted to pass beneath the outer ends of the door'hinges when the doors are in closed position and to'thereby support the hinges and therefore the doors. The outer end of each door hinge H is formed with a rearwardly and upwardly extending portion [9 which efiectively prevents the 1ower end of its corresponding latch from sliding off the end of the hinge when the latch and the hinge are in locking relationship. Pivot brackets 20, extending partially beneath doors 4 and 4 and secured thereto at spaced intervals along the length of the doors, are supported by shafts 5 and 6 to which they are fixedly secured as by keys. Op crating brackets 21 are also secured to shafts 5 and 6 by keys at the end of the car outside sloping wall 3 thereof and normally extend upw'ardly above the plane of the bottom of the car.

The structure above described is old in the art and for its operation there was formerly supportedat the end of the car between operating brackets 2|, a crank and windllass assembly by which the operating brackets 2i could be pivoted upwardly to close car doors ti and 6'. With that closing mechanism, however, which was manually operated, the closing of the doors was a tedious and laborious operation requiring "considerable time. Additionally, the mechanism had to be manually maintained in door-closing condition until the latches l3 could be operated to lock the doors in closed position. Also, as the mechanism was individually secured to brackets 2|, theforce supplied by the crank and Windlass mechanism to close the doors was not equalized between the doors and if, for any reason, one of the car doors would not close, the otherwould not close either.

The apparatus of my invention is aimed at the replacement of the former manually operated mechanism by an automatically operated mechanism which providesequal closingiforces to the car doors and which also provides a time lag after it has been operated to close the doors and before it has been deactivated and returned to its original position, in which the latches l3 may be safely pivoted to secure the doors in closed position. To this end my apparatus comprises a fluid pressure cylinder 22 supported at one end of the car on the center sill structure 23 of the car between longitudinally extending shafts 5 and 6; For the purposes of this description and as contemplated for actual use, the fluid to be used in the operation of the mechanism will be compressed air. An inlet conduit 24 is provided to supply compressed air to the lower end of cylinder 22.

A piston 25 (Figs. 3 and 5) is reciprocably mounted in cylinder 22 and supports'on its upper side a piston rod 26 of tubular shape which extends through an opening 21 in the upper wall 28 of cylinder 22. A pulley or sheave 29 is supported on a bearing 39 secured in the upper end of tubular piston rod 28. Guide followers 3| are secured to the outer side of piston rod 2 6 and are adapted to ride between guides 32 of a guiding framework which is supported on the upper end 28 of cylinder 22. For further support the upper ends of each of the members or elements 32 of the guidin framework are additionally se cured to end wall 3 of the dump car. As seen most clearly in Fig. 2', each pair of guiding elements $2 is provided with a pair of sheave supporting members 33 having a seriesof corresponding holes 34 in which bearings for guiding sheaves or pulleys 35 may be mounted. A cable 36 (Fig. 2) is adjustably attached at its opposite ends to operating brackets 2| of the car doors by means of auxiliary brackets 37 secured to operating brackets 2i andeach having a series of holes therein whereby the position of attachmerit may be varied. Pulley or sheave 29 supported at the upp r end of piston rod 26 is adapted to freely engage the center portionof the cable which. passes over it and which passes beneath fixed guiding sheaves 35. Itwill thus be seen that when compressed air is supplied to the lower end of cylinder 22 through conduit 24' that piston 25 and piston rod 26 will be urged up wardly and thatpulleyj or sheave 29 will in turn draw the, ends of. c'able'36 inwardly and upweu dly. to pivot operating brackets 2| on shafts 5 and 6,.

wall 3 of-the canto permit the piston rod 26' to be elevated a suflicient distance to closetightly the doors and a box-like covering member 3' is provided to cover the opening topreyentore loaded in the-carf-rompassing. through theopein. ing.

The supply of compressed air to conduit 24 is controlled by a three-way valve shown in detail. in Fig. 4. Briefly,.it comprises a block. 38 hayingv a valve chamber 39 in communication with which is conduit 24 which leads. from the valve to cylinder 22 and conduit 40 leading from a compressed air supplyconduit 40' (Fig; 2)" t'othe valve. A standard valve element M is reciprocably mounted within valve chamber 39 and is provided at each end with an air-tight piston cup 42. When in the position shown in Fig. 4, the valve element places conduit 24, and therefore the interior of cylinder 22, in communication with the atmosphere through the valve and a vent 43. A valve operating handle or lever 44, loosely pivoted by a pin 45 to a portion 46 of the valve body 38, is provided to urge valve element 4| inwardly in valve chamber 39. A roller bearing 47 is supported in the outer end of valve element 4| to receive, with negligible friction, the force supplied by lever 44 to the valve element. When the valve element 4| is urged to its inner position, as will be the case when lever 44 is moved to its position shown in dotted lines in Fig. 4, conduit 24 is placed in communication with conduit 4|] which leads from the source of compressed air, and therefore compressed air is supplied to cylinder 22. The valve, as described, is not in itself a part of my invention.

A bracket 48 is supported by the same portion of the framework that supports the valve and is provided with steps 49 and 59. Operating lever 44 rests on step 59 when the valve is in venting position and on step 49 when the valve is in air supplying position. When the valve element 4| is moved inwardly within chamber 39, a certain amount of air contained in the inner end'of chamber 39 is compressed between that end of the chamber and the inner end of the valve element because of the fact that piston cup 42 at this end of the valve element is air tight. In other words, when valve element 4| is moved inwardly in the valve chamber, it is so moved against the pressure of the compressed and trapped air. Therefore, it will be clear that the valve element 4| is always urged outwardly either by compressed air from conduit 49 or by the compressed air entrapped at the inner end of chamber 39. When lever 44 is moved to the dotted line position, it is so moved against an opposing force exerted on the valve element and when it is in dotted line position on step 49 and is released it will be urged against the shoulder between steps 49 and 59 and remain there until positively lifted above the shoulder so that it may return to its original position, and thus piston 25 and its supported structure will remain in their uppermost, or door closing, positions until the lever 44 is released.

Referring again to Fig. 3, I will now describe the novel time-delay device by which the operating lever 44 is released from step 49 a certain predetermined length of time after the compressed air operating mechanism eifectively closes the doors of the car. A pressure-tight cylinder 5|, in which there is contained a fixed quantity of fluid 52, such as oil, has its upper end connected by a conduit 53 to the interior of cylinder 22 at a point just below the position in which piston 25 will be when it has moved upwardly in cylinder 22 to effectively close the doors of the car. A second fluid or pressure-tight cylinder 54 is supported on bracket 48 by a U-clamp 55 directly beneath step 49 of the bracket and has its lower end connected by a conduit 56 to the lower end of cylinder 5|. Conduit 56 is connected to cylinder 54 by a connecting member 51 having therein a restricted orifice 58. A piston 59 is reciprocably mounted in cylinder 54 and is spring urged towards the bottom of the cylinder by a spring 69 contained in the cylinder. A piston rod 6| is supported by piston 59 and extends through the upper end of cylinder 54, its own uppermost end being positioned just below the lever 44 on step 49 of bracket 48 when piston.

59 rests at the lower end of cylinder 54. Piston 59 is adapted to be urged upwardly against the force of spring 60 when compressed air is admitted to cylinder 5| through conduit 53, thereby forcing oil 52 through conduit 56 and restricted orifice 58 into cylinder 54. Compressed air is, of course, admitted to conduit 53 only when the operating lever 44 of the three-way valve is resting on step 49 and compressed air has thus been supplied to cylinder 22. When piston 59 rises in cylinder 54, piston rod 6| abuts the lower side of the operating lever and raises it, thereby releasing it from engagement with the shoulder between steps 49 and 50 and permitting-it to return to its position, as shown in solid lines in Fig. 4. Because of the restricted orifice 58, through which oil must pass from cylinder 5| to cylinder 54, the flow of oil between these cylinders is-relatively slow and a certain period elapses between the time when compressed air is initially admitted to cylinder 5|, above the oil level therein, and the time when a suflicient amount of oil has been admitted to cylinder 54 to raise the piston and the piston rod to release operating lever 44. It is contemplated that during this period, which may be made as long as desired as, for instance, by varying the size of the orifice 56 or the size of spring 60, the door latches I3 of the car may be operated to lock the doors in closed position.

A shield 62 (Fig. 1) is secured to the upper edge of end wall 3 of the car and extends outwardly therefrom over my apparatus to protect it from ore which may overflow the end of the car or which may be dropped over the end during loading.

The operation of my fluid-operated door closing mechanism in its entirety is briefly as follows: Assuming that the doors of the car are in opened position and that therefore piston 25 is at its lowest position in cylinder 22, the three- Way valve is operated by lever 44 to admit compressed air to cylinder 22, as described, operating lever 44 being maintained on step 49 by the shoulder between steps 49 and 50. Under the influence of the compressed air so admitted to cylinder 22, piston 25 moves upwardly in the cylinder, thereby moving sheave or pulley 29 upwardly and drawing cable 36 inwardly and upwardly to pivot the doors 4 and 4' of the car to closed position under equal forces. When the doors have thus been pivoted to closed position and piston 25 is in its uppermost position, the interior of cylinder 22 is in communication with the interior of cylinder 5| through conduit 53 and compressed air is thereby supplied to cylinder 5| above the level of the oil therein. Oil 52 then begins to flow through conduit 56 and restricted orifice 58 into cylinder 54 to force piston 59 and piston rod 6| upwardly therein. After a predetermined length of time, suflicient oil will have been admitted to cylinder 54 to cause piston rod 6| to rise sufiiciently to release operating lever 44 of the valve from step 49, thereby per= mitting valve element 4| to return to its normal position. As stated, during this period of time, latches I3 may be placed in looking position below the outer ends of door hinges to thereby lock the doors of the car closed. When valve element 4| returns to its original position, cylinder 22 is vented through conduit 24, the valve. and vent 43, and piston 25 descends within cylinder 22 to its original position where it remains untiili it has to be used again to clcse the car doors; Compressed for: 'tn'e o eration' of the mechanism may beprovidedfrom any source-but it is contemplatdithat it' will be supplied-from the :compressor i of the locomotive-engine used Ito draw the'dump carby means independent' of-the brake line or system;

1. I-n aL duzn p ca'r having 'a -pair 'ofido'wnwardly opening :doors an d latchingmearis' for 'maintainin'g thedoor' in closed-position after they have been closed, apparatus for closing thedoors which comprises a cable securedat one end tooneofthe doots and-at its other endlto the other door, means freely-engaging thecable int'ermediate -th'e cable en'd's, andmeaiis ior foreingl-said cable engaging means upwardly: to 'closethe doors; whereby the closing force acting up'onone door is' always --eq-ua-l to the closing force acting upon-the other door;

2. Ina- -dump car 'h'a-vin'ga pairof downwa'rdly opening-doors and lat'ehingmeans for: maintaining th'e doors in closed 'position after theyhave been closed, apparatus for closing the doors which comprises a fluid pressure cylinder, a" piston within said "cylinder and movablethereinunder the force or a fluid admitted to the eviinder under=pressure,-a piston rod secured to said piston, means for "supplying fluid under pressure to the cylinder belmwthepiston; a cable secured atone end to one *of the' doors and at I its other end to "the-"other door, and means 'supportedon the-piston rod and freely engaging the cable intermediate theends-of the cable, whereby-when fluidunder pressure is supplied 3 to the cylinder the" piston therein is* urged upwardly thereby urging the cable engaging means upwardlyahd under pressure 'to 'the cylinder below the piston,

a c'abl'esecured at one en'd to one of the brackets and -at its-othe'r "end to the other bracket, and

means supp'ortedon the piston rod and freely' engaging the ce'rble intermediate the ends of the cable, whereby when fluid under "pressure is supplied to the cylinder the piston therein is urged upwardly thereby urging the" cable engaging means upwardly and exerting equal forces upon I the brackets secured to the pivotsupportsto urge the doors closed with equal force."

4. In a'dump car' h'aving downwardly opening doors, means operat'edby" fluid undr pressure for 'clo'sing said doors and-latching means for" maintaining the doors in closed position after they have been closed, apparatus "for controlling the fluid-operated means'which comprisesv'alve means for controlling the flow of fluid to and from. said fluid op'er'ated means, means 'for mov ing the val-ve to a-position to supply fluid underpressure to the fluid-operated means,--means for maintaining said' valve in said position, a time-- delay-device resp'oiisive' to movement of the fluidoperated-means to" deer erasing-position for mot 8. ing. said valve meansto its original positionin which thesup'ply of fluid to the fluid operated means is discontinued and in which fluid that has been supplied to the fluid-operated means is permitted to 'flow from the fluid-operated means, said time-delay device 'providing'aperiod of time'in which the car doors are-held closed by the fluid-operated means and during which the latching means may be adjusted to maintain :the doors in closed position.

5. In a dump car having downwardly opening doors, means operated by fluid under pressure for closing said doors and latching means for maintaining the doors in closed position after Ithey. have been closed, apparatus for controlling.

the fluid-operated means which comprises valve means-for controlling the flow of fluid to and from said fluid-operated means, manually operable meansfor moving the valve. to a position-to isupply fluid under pressure to the fluid-operated means, means for maintaining said'valve in said position, said valve when in said position being acted upon by a force which urges it toward its original position, and a time-delay device responsive to the volume and pressure of the fluid supplied to the fluid-operated means for releasing the valve so that it returns to its original position in which the supply of fluid to the fluid-operated means is discontinued and in :which fluidthat has been supplied to the fluidoperated means is permitted to flow from the fluid-operated means, said time-delay device providing. a period of time in which the doors are held closed by the fluid-operated means and :during which the latching means may be adjusted to maintain the doors in closed position. 6. Apparatus in accordance with claim 5'in which the time-delay device comprises a pressure-tight cylinder containing a supply of fluid. a second cylinder, a piston reciprocably mounted in said second cylindena piston rod supported by said piston and extending through one :end of said second cylinder and adapted toact upon said valve means to release the valve-so that it ;,may return to its original position, aconduit connecting one-end of said first-mentioned pres sure-tight cylinder to the fluid-operated means, a conduit having a restricted orifice and connecting the other end of said first-mentioned gcylinder to the end of said second cylinder below the piston contained therein, whereby the piston and its supported piston rod are urged away from said last-mentioned end 'of 'the second cylinderwhen the fluid under pressure :in the fluid goperated means is permitted'to enterthe first mentioned connecting .conduit.

7. Apparatus in accordance with claim- 6 which includes spring means contained in the second cylinder and acting. upon the piston therein to oppose movement of the piston as'a result of the admission into said second cylinder of flui'dfrom the first-mentioned cylinder .GFA'RESET car essness-crass The following references are ofrecord in the file of this patent:

UNITED STA-m PATENTS Number Name Date 732,348 fiaflis'ol l ua June 30, I903 FOREIGN PA'IENTS' Number M Country, D'ate 139,2?!) France- Oct-i2, i930

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