US3220063A - Retaining device for railroad car doors - Google Patents

Description

Nov. 30, 1965 T. 2. HERR 3,220,063

RETAINING DEVICE FOR RAILROAD CAR DOORS Filed May 22, 1963 2 Sheets-Sheet 1 FIG. I

22 2| L# n II I I I J I I I I I F J IE] X 29 28 30 I6 47 I9 \II [IF 2 o I I 10A 1L: I \34 I3 24 3 I 25 INVENTOR. THEODORE Z. HERR AT T0 R NEYS Nov. 30, 1965 T. Z. HERR RETAINING DEVICE FOR RAILROAD CAR DOORS Filed May 22, 1963 2 Sheets-Sheet 2 #34- 44 4s A y INVENTOR. 2;; r: ,I

L THEODORE Z.HERR -I P. h flu BY I I I l V j a 3 [0 45 43 MAXIMUMTRAVEL i g 3 BEFORE LATCHING ATTORNEYS United States Patent corporation of Ohio Filed May 22, 1963, Ser. No. 282,401 6 Claims. (CI. 20-23) This invention relates to a sliding railroad car door and more specifically to a mechanism for restraining the sliding movement of such car doors.

In its broadest aspect, this invention relates to a lever system for controlling the operation of a latching device.

In its most specific aspect, the invention contemplates a latching device secured to a railroad car door with the latching device functioning to secure the door in a plurality of adjusted positions thereby to restrain the door from free rolling movement.

The plug door is a commonly used type of door in the railroad car industry and is one which is flush with the external siding of the railroad car when in the closed position. To expose the door opening, it is necessary to displace the door laterally away from the side of the car and along slide tracks longitudinally the length of the car. These doors are attached to the car through rollers mounted on a track and represent a potentially freerolling body, but ordinarily move with the car until the car has encountered a decelerating or accelerating force. Upon application of an external decelerating or accelerating force on the car and inasmuch as the doors are ordinarily mounted for movement relative to the car on rollers having a minimum of friction, the door, due to its inertia, continues at its initial velocity until restrained by an external force.

This external force heretofore has taken the form of a stop secured to the side of the car which abruptly halts the rolling movement of the door at the completion of its travel. Since these railroad car doors are of a considerable weight and are brought to a halt within a very short distance, the forces on the door frequently are in the order of 70,000 lbs. Obviously, with forces of this magnitude acting on the door, considerable damage frequently results from the impact.

In order to lessen the effects of the restraining impact, it would be conceivable to extend the distance over which the restraining force is applied and thereby reduce the adverse elfects on the door. However, this is impractical because of the expense and space limitations.

Accordingly, it is an object of this invention to provide a device for a railroad car door to minimize the restraining forces on the door.

Another object of this invention is to provide a means for restraining the free rolling movement of a railroad car door.

It is a further object of this invention to provide a latching device for a railroad car door wherein the door may be secured in a plurality of adjusted positions along the longitudinal length of the supporting track.

It is a still further object of this invention to provide a latch device for restraining movement of a railroad car door which latch device is inexpensive and of minimum dimensions and easily attached to existing doors.

It is another object of this invention to provide a lever system for controlling the operation of a latching device on a railroad car door.

It is a more specific object of this invention to provide a latching device for restraining a railroad car door wherein a plurality of slots are provided in the car door track and a spring biased latch device including a manually operable handle are secured to the car door with the latch "ice device being receivable in any selected one of the slots in the track thereby securing the car door in an adjusted position along the longitudinal length of the track.

It is a still more specific object of this invention to provide a railroad car door restraining mechanism including a plurality of slots in the car door supporting track, a spring biased latched mechanism secured to the car door with the latch mechanism including a portion receivable in the slots in the track, and a manually operable lever pivotally mounted on the car door and operable to pivot the latching mechanism against the bias of its biasing means thereby to remove the restraint on the car door.

To the accomplishment of the foregoing and related ends, said invention then consists of the means hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail one approved means of carrying out the invention, such disclosed means, however, constituting but one of the various ways in which the principles of the invention may he used.

In the drawings:

FIG. 1 is a front elevational view showing the invention as it is incorporated on a railroad car door;

FIG. 2 is a fragmentary side elevational view taken along line 2-2 of FIG. 1 showing the latching mechanism;

FIG. 3 is a front elevational view of the latching mechanism illustrated in FIG. 2.

Referring now to the drawings which illustrate one preferred embodiment of the invention, the numeral 10 designates one side wall of a conventional railroad car. A door opening 11 is formed in the side wall and is adapted to be closed by a laterally movable door 12. In the closed position, the door 12 is seated in the door opening and is substantially flush with the external surface of the side wall 10.

To move the door laterally out of the door opening 11 for longitudinal movement along the side wall 10 on track 13, there are provided spaced apart parallel vertical pipes 14, 15. Each of the pipes 14, 15 is rotatably secured to the door 12 by means of brackets 16, 17, 18, 19. Secured to the upper end of the pipes 14, 15 are cranks 20, 21, respectively. The cranks 20, 21 extend upwardly behind a retainer 22 and are provided with rollers which guide the door in its longitudinal movement and retain the upper portion of the door in the proper position relative to the car. Secured to the lower end of each of the pipes 14, 15 are cranks 24, 25 respectively. The cranks 24, 25 are journalled in roller hangers 26, 27 mounted upon the track 13 thereby to facilitate sliding movement of the door 12. It is believed apparent that upon rotation of the pipes 14, 15, the upper cranks 20, 21 and the lower cranks 24, 25 are caused to rotate. As is apparent from an inspection of FIG. 1, all of the cranks 20, 21, 24, 25 are normal to the plane of the door when the door is in the closed position. Thus, upon rotation of the pipes 14, 15, the cranks are pivoted to a position approximating a parallel relationship with the door thereby causing the door to be displaced laterally outward from the plane of the cars siding. After this has been accomplished, the door may be displaced longitudinally along the track 13 thereby exposing the door opening.

To accomplish the rotation of the pipes 14, 15, there is provided a pair of operating levers 28, 29. The free end of the levers 28, 29 are restrained in a latch mechanism 30 with the opposite ends of each of the levers being pivotally secured to clevises 31, 32 respectively. The clevises 31, 32 are attached to pipes 14, 15 so that upon rotation of the levers 28, 29 a corresponding rotation is imparted to the pipes.

Inasmuch as rollers are mounted on the upper ends of the cranks 20, 21 and the cranks 24, 25 are received on roller hangers 26, 27, it is believed apparent that the door, when displaced laterally from the door opening, constitutes a body capable of free rolling movement along track 13. As such, the door, due to its weight and iner tia, will react to any external force applied to the car independently of the reaction of the car itself. Thus, assuming the car to be moving at a constant velocity, the door will be at rest relative to the car and will be moving at the same velocity as the car. However, should the car receive an accelerating or decelerating force, the door wouldtend to maintain a constant velocity and, due to its free rolling characteristics, would roll along the track 13. Assuming the car is brought to an abrupt halt, the door would roll along the track substantially at its original velocity until it is halted by the fixed stop device commonly provided on the side of the railroad car.

The effect of the door reacting against a fixed stop on the car is to deliver a blow of substantial magntitude to the door. Assuming a car door of approximately 1200 lbs. and moving at a velocity of from to mph, the effect of the usual rigid stop device is to impart a blow of approximately 70,000 lbs. to the car door. Obviously, impacts of this magnitude are the occasion of substantial damage to the door and devices adequate to absorb this energy are difficult to design within the space and cost limitations.

A further problem represented by the existing doorandstop arrangement is the tendency of the door to be lifted from the track during impact causing permanent detrailment of the car door. Such a situation occurs due to a couple resulting from the impact, which couple tendsto cause the lower rear corner of the door to be raised from the track. Once the door is lifted from the track, the roller hanger is dropped and the door is derailed.

As a solution to these problems, there is illustrated in FIGS. 2 and 3 a latching mechanism which serves to retain thecar door in any adjusted position along the track thereby restraining its free-rolling characteristics. The latching mechanism comprises a latch designated generally by the reference numeral 33. This latch consists of an essentially bellcrank lever having a depending leg 34 and bifurcated arm portions 35a and 35b. The latch 33 is pivotally received'on a pivot member 36 which in turn is journalled in supporting brackets 37, 38 secured to the car door 12. A torsion spring 39 is mounted on the pivot pin 36 with one portion 40 of the spring 39 abutting the depending leg 34 and the other portion 41 of the spring 39 being in abutment with the bracket plate 42.

The latch 33 under the bias of the spring 39 tends to pivot in a clockwise direction around the pivot 36 as viewed in FIG. 2. However, the latch is restrained from a free pivoting movement due to the abutment of the oifset end 43 of the depending leg 34 with the track 13 and the abutment of arms 35 with plate 42.

Provided in the track 13 is a plurality of openings or slots 44 separated by land portions 45 with the alternate land and slot arrangement being provided along the entire longitudinal length of the track 13. It is to be noted that the slots 44 are provided in but one leg of the track 13 with the slots facing inwardly toward the railroad car; the other leg of the track 13 covers the slots so that hand contact with the slots is prevented. Projecting from the lower portion 43 of the depending leg 34 is a lug 46 which is receivable in the slots 44. With the lug 46 received in any of the slots 44, the car door is restrained from movement relative to the track 13 thereby preventing the free rolling and resulting impact described above.

The bias of the spring 39 serves to maintain the offset portion 43 of the depending leg 34 in engagement with the track 13 and thus retain the lug 46 in one of the slots 44. In order to remove the lug 46 from the slot 44, there is provided an actuating handle 47 which is independently pivotally secured at 48 to the upper end 49 of the bracket plate 42. The separate mounting of the handle 47 permits a limited amount of independent pivoting movement for the handle relative to the door and the latch. The handle 47 is disposed vertically along the face of the door 12 and has offset arms 50a, 5% adapted to abut the arms 35a, 35b respectively. However, in the normal upright position of the lever 47, both of the arms 50a, 5012 are removed from the abutting relationship. Should the handle 47 be pivoted to the position shown in dotted lines in FIG. 3, the arm 50b would abut the arm 35b of the latch 33 causing the latch to pivot about the pin 36 against the spring bias of the spring 39. This pivoting movement of the latch 33 would retract the lug 46 from the slot 44 in the track 13 thereby releasing the doorfor sliding movement longitudinally of the track. Similarly, should the handle be pivotedcounterclockwise, as viewed in FIG. 3, the arm 50:: would abut arm 35a and thereby retract the lug 46 from its associated slot.

The latching mechanism described here remains operative so long as the door is in the fully opened. position and will automatically latch the door in a position along the track upon release of the lever 47. In the event that the handle 47 is released at a position where the lug 46 is aligned with the land, 45, the door will be free to move relative to the track only a short distance and, as soon as the lug 46 is aligned with a slot 44, the bias of the spring 39 will force the lug into the slot whereby to latch the door in position. The lateral movement which occurs upon closing the door 12 serves to disengage the latch mechanism 33 from the track 13. However, the bias of the spring 39 is restrained by the engagement of the upper surface of the arm 35a, 35b with the retaining plate 42 on the arms 50a, 50b.

It is believed apparent that with the device above described, the door 12 is precluded from rolling movement relative to the railroad car. From computations that have been made, the force on a 1200-lb. door which is secured to a railroad car impacted by another car at humping speed is in the order of 12,000 lbs. Obviously, a force of 12,000 lbs. is more easily absorbed than the force of 70,000 lbs. which was developed, as described above, when the door was free rolling.

Further, the above-described derailment problem has been obviated with the instant latching device. Inasmuch as the center of gravity of the door lies midway between the two roller hangers 26, 27 and the latch 33 is in critical alignment with this point, any overturning couple present is insufficient to raise the door from the track. Also, any upward movement of the door is prevented by the abutment of the upperv surface of the lug 46 with the track slot 44.

Other modes of accomplishing the results disclosed above will be apparent to those having ordinary skill in the art. Thus, a friction member might be used in lieu of the lug and slot arrangement illustrated. Also, the actuating handle might be made integral with the lug carrying memben These. two alternatives are purely illustrative and not meant to be an exhaustive listing of the variations contemplated by this invention.

For ease of description, the principles of the invention have been set forth in connection with but a single illustrated embodiment. It is not my intention that the illustrated embodiment or the terminology employed in describing it be limitinginasmuch as variations in these may be made without departingfrom the spirit of the invention, but rather, it is my desire to be restricted only by the scope of the appended claims.

I claim:

1. In combination,

a railroad car having a door opening,

a door adapted to close the opening in the car,

a track spaced from and secured to said car and mounting said door for longitudinal movement therealong,

said track having a plurality of slots spaced along the longitudinal length thereof and facing said door with a portion of said track covering the slots on the side of the track opposite to the door,

latch means mounted on said door for movement toward and away from said track,

said latch means having a portion adapted to enter the slots in said track thereby to secure said door in a plurality of positions along the length of said track and prevent movement of said door relative to said car.

2. In combination,

a door adapted to close an opening in a railroad car,

a track on the car,

means rollingly mounting said door on said track,

operating means on said door for displacing said door from the door opening,

said track having a plurality of slots spaced along the longitudinal length thereof, with the slots facing said door,

latch means pivotally secured to said door,

said latch means having a portion adapted to enter the slots in said track,

a handle separate from said latch means,

means pivotally mounting said handle on said door,

said handle including a portion thereon adapted to abut said latch means in at least one position of said handle whereby said latch means may be caused to pivot on said door.

3. The combination of claim 2 wherein said latch means includes,

biasing means adapted to bias said portion of said latch means into the slots in said track when said portion is aligned with any of the slots.

4. In combination,

a door adapted to close an opening in a railroad car,

a track on the car,

means rollingly mounting said door on said track,

operating means on said door for displacing said door from the door opening,

said track having a plurality of slots spaced along the longitudinal length thereof,

latch means pivotally secured to said door,

said latch means having a portion adapted to enter the slots in said track thereby to secure said track in a plurality of positions along the length of said track,

biasing means adapted to bias said portion of said track means into engagement with the slots in said track, and

manually operable handle means on said door movable independently of said latch means and being operable to disengage said portion of said latch means from said slots in said track against the bias of said biasing means,

5. In combination,

a door adapted to close an opening in a wall,

a track secured to the Wall and mounting said door for longitudinal sliding movement therealong,

said track having a plurality of slots spaced along the longitudinal length thereof,

latch means pivotally mounted on said door for swinging movement toward and away from said door,

said latch means having a portion adapted to enter the slots in said track thereby to secure said door in a plurality of positions along the length of said track,

said latch means comprising a lever pivotally mounted on the door,

said lever including a depending leg portion and bifurcated arm portions,

said portion of said latch means comprising a lug on said leg portion,

biasing means normally biasing said lever to a position wherein said lug is in engagement with a slot in said track, and

a handle pivotally secured to the door, said handle having spaced apart arms adapted to engage said bifurcated arm portions of said lever and pivot said lever against the bias of said spring thereby to withdraw said lug from a slot in said track.

6. A latching mechanism adapted to restrain the movement of a sliding railroad car door comprising,

a lever pivotally secured to the door,

said lever including a depending leg portion and bifurcated arm portions,

a lug projecting from the lower end of said depending leg portion and adapted to enter slots spaced along the track mounting said door,

biasing means cooperating With said lever to bias said lug into one of the slots,

a handle secured to the door for pivotal movement,

said handle including spaced apart arms adapted to cooperate with the bifurcated arms on said lever whereby, upon pivoting of said handle in one direction, one of said spaced apart arms abuts one of said bifurcated arms on said lever causing said lever to be pivoted against the bias of said spring and withdraw said lug from its associated slot.

References Cited by the Examiner UNITED STATES PATENTS 1,430,555 10/1922 Jager 2022 1,468,053 9/ 1923 Townsend 2019 X 2,699,204 1/ 1955 Davis 2052.8

FOREIGN PATENTS 598,200 5/1960 Canada. 702,564 1/1931 France.

HARRISON R. MOSELEY, Primary Examiner.

Claims (1)

1. 4. IN COMBINATION, A DOOR ADAPTED TO CLOSE AN OPENING IN A RAILROAD CAR, A TRACK ON THE CAR, MEANS ROLLINGLY MOUNTING SAID DOOR ON SIAD TRACK, OPERATING MEANS ON SAID DOOR FOR DISPLACING SAID DOOR FROM THE DOOR OPENING, SAID TRACK HAVING A PLURALITY OF SLOTS SPACED ALONG THE LONGITUDINAL LENGTH THEREOF, LATCH MEANS PIVOTALLY SECURED TO SAID DOOR, SAID LATCH MEANS HAVING A PORTION ADAPTED TO ENTER THE SLOTS IN SAID TRACK THEREBY TO SECURE SAID TRACK IN A PLURALITY OF POSITIONS ALONG THE LENGTH OF SAID TRACK, BIASING MEANS ADAPTED TO BIAS SAID PORTION OF SAID TRACK MEANS INTO ENGAGEMENT WITH THE SLOTS IN SAID TRACK, AND MANUALLY OPERABLE HANDLE MEANS ON SAID DOOR MOVABLE INDEPENDENTLY OF SAID LATCH MEANS AND BEING OPERABLE TO DISENGAGE SAID PORTION OF SAID LATCH MEANS FROM SAID SLOTS IN SAID TRACK AGAINST THE BIAS OF SAID BIASING MEANS.

Images