Hopper Gate Latching Mechanism

Abstract

This disclosure deals with a lock mechanism for a discharge gate of a railway hopper car. The gate includes a frame secured to the lower end of a hopper of the car and extending around the hopper opening, a door plate movably supported by the frame, and means for horizontally moving the door plate between a closed position where it closes the hopper opening and an open position where it uncovers the opening. A lock mechanism is provided for holding the door plate in its closed position. The lock mechanism is both manually engageable and self engageable. In the event the trainmen neglect to manually engage the lock mechanism, shifting of the door plate when the car is moved results in automatic or self engagement of the mechanism.

Description

Hopper cars are commonly used in the railroad industry to convey a variety of commodities, such a car including one or more hoppers on the underside thereof and a discharge gate for each hopper to control the discharge of the commodity from the car. A common type of gate for a hopper car of the type used to haul finely divided commodities such as wheat or cement or the like includes a frame secured to the hopper around the discharge opening thereof, a door plate slidably mounted on the frame for horizontal movement between open and closed positions, and a manually operated mechanism for moving the door plate. Such a gate usually also includes a manually operable lock for holding the door plate in its closed position.

A problem frequently arises with such a construction when a trainman neglects to engage the lock after emptying the car. Subsequent movement of the car, as during switching, results in the door plate shifting back and forth on the frame, and such shifting can be violent enough to damage parts of the gate or result in loss of the door plate.

The foregoing problem is eliminated in accordance with the present invention by providing a discharge gate including a lock which is both manually engageable and also selfengageable. The lock includes a latch which is movably mounted adjacent the door plate of the gate. When the door plate is closed and the latch is in its engaged position, the latch abuts the door plate and holds it shut, and when the latch is in its disengaged position, the latch is displaced from the door plate and it may be opened. If the latch were left in its disengaged position, shifting of the door plate would result in the plate striking the latch and moving it to a tripped position. When the door plate subsequently shifts to its closed position the latch automatically drops by gravity into its engaged position where it holds the plate closed until manually disengaged.

The objects and advantages of the invention will further become apparent from the following detailed description taken in conjunction with the accompanying figures of the drawings, in which:

FIG. 1 is a fragmentary plan view of a discharge gate embodying the present invention;

FIG. 2 is a sectional view taken on the line 2--2 of FIG. 1;

FIG. 3 is a partial sectional view taken on the line 3--3 of FIG. 1;

FIG. 4 is a fragmentary enlarged plan view of a portion of the gate showing a lock mechanism thereof in its engaged position;

FIG. 5 is a view generally similar to FIG. 4 but showing the lock mechanism in a tripped position;

FIG. 6 is a sectional view taken on the line 6--6 of FIG. 4;

FIG. 7 is a view similar to FIG. 6 but showing the lock mechanism in a fully disengaged position; and

FIG. 8 is another view similar to FIG. 6 but showing the lock mechanism in its tripped position.

With specific reference to the drawings, FIGS. 1 through 3 show a discharge gate adapted to be attached to the lower end of a hopper of a hopper car. The discharge gate comprises a generally square frame 10, a door plate 11 mounted on the frame 10 for sliding movement in a generally horizontal plane, a manually operated gear mechanism 12 for moving the plate 11 between open and closed positions, and a lock mechanism 13 for holding the door plate 11 in its closed position. The frame 10 fits around the lower end of the hopper and is open at its center, and the door plate 11, when in its closed position as in FIG. 2, closes the opening of the frame. The gear mechanism 12 may be manually operated to move the door plate 11 toward the right, as seen in FIG. 2, to uncover the center opening of the frame 10 when the contents of the hopper car are to be discharged. The lock mechanism 13, when engaged, holds the door plate in its closed position.

The frame 10 comprises a pair of spaced-apart side plates 16 and 17 which, when the gate is installed on a hopper car, extend longitudinally of the length of the car and are fastened to the walls (not shown) forming the hopper at the lower end thereof. As shown in FIG. 3, each side plate 16 and 17 slants downwardly and inwardly from its upper edge, the upper slanting portion of each plate being secured, as by welding, to the outside of a hopper wall. At the lower end of the slanting portion, each side plate is bent to extend generally horizontally and thus form a ledge 18, and then extends straight downwardly to form a wall 19 of the discharge opening or chute of the gate. The lower end of each side plate is bent laterally outwardly, as at 19a (FIG. 3), in order to strengthen the side plate.

At its forward end, the frame includes a front plate 21 (FIGS. 1 and 2), the upper portion thereof also slanting and being secured to the outside of a hopper wall. The front plate 21 is also bent inwardly to form a generally horizontally extending ledge 22 at the same level as the ledges 18 of the side plates 16 and 17. The lower portion of the front plate 21 slants downwardly and inwardly to form another wall 23 of the discharge opening of the gate. The front plate 21 is secured to the two side plates 16 and 17 and to the hopper wall, as by welding, which process may also be used to secure other parts of the frame together.

The back or rearward side of the frame includes a rear upper plate 26 and a rear lower plate 27, the upper plate 26 slanting downwardly and inwardly and being secured to the outside of another wall of the hopper. The lower plate 27 also slants downwardly and inwardly and forms the fourth wall of the discharge opening of the gate. The two plates 26 and 27 are vertically separated, thus forming a space 28 therebetween through which the door plate moves. The upper end portion of the lower plate 27 is bent rearwardly to form a horizontally extending ledge 29 which is also at the level of the ledges 18 and 22 of the side and front plates.

In addition, the frame 10 includes a plurality of bars and angles which are indicated generally by the reference numeral 31 in FIG. 2. These members are secured as by welding to the frame plates described above in order to strengthen them. Further, a longitudinally extending door support plate or bar 32 (FIGS. 1 to 3) extends between and is secured to the front plate 23 and the rear lower plate 27 at approximately the center of the discharge opening of the gate. The upper edge of the bar 32 is at the level of the upper surfaces of the ledges 18, 22 and 29, as shown in FIG. 2, and it supports the center area of the doorplate.

The door plate 11, when in its closed position as shown in FIG. 2, is supported at its edges by the ledges 18, 22 and 29 and at its center by the bar 32. The rearward end portion of the door plate 11 extends through the space 28 between the upper and lower plates 26 and 27 and is bent upwardly, as indicated at 36 in FIG. 2. A pair of guide plates or bars 37 (FIG. 3) are secured to the two side plates 16 and 17 above the ledges 18, and the side edges of the door plate 11 extend into the spaces between the ledges 18 and the guides 37. Further, a plurality of hold-down lugs 38 are secured to the front plate 21 above the ledge 22, and the forward end portion of the door plate 11 fits snugly in the space between the ledge 22 and the lugs 38 when the door plate is fully closed. Thus, the door plate 11 is slidably supported on the ledges 18, 22 and 29, and it may be moved toward the right from the closed position shown in FIG. 2 to its open position where the discharge opening of the gate is uncovered. The two guides 37, of course, prevent the doorplate 11 from tipping in the clockwise direction, as viewed in FIG. 2, when it is partially or entirely open.

The gear mechanism 12 for moving the door plate 11 between its open and closed positions includes two racks 41 and 42 (FIGS. 1 to 3), each rack consisting of three segments or sections. The racks 41 and 42 are secured to the underside of the door plate 11 adjacent the side edges thereof and extend longitudinally in the direction of movement of the door plate 11. With reference to FIGS. 2 and 3, portions at the ends of the lower plate 27 are cut and bent horizontally to provide clearance for the racks 41 and 42. The two racks 41 and 42 project rearwardly from the plate 11 and overlie two spur gears 44 and 45, and teeth on the undersides of the racks mesh with the spur gears 44 and 45. As shown in FIGS. 1 and 2, a metal block 50 is rigidly secured to the upper surface of the portion of each rack which extends rearwardly of the door plate 11 in order to strengthen this area of the racks. The gears 44 and 45 are secured to a laterally extending operating shaft 46 below the level of the plate 11, the operating shaft 46 being rotatably supported on bearings 47 fastened to rearwardly extending end portions of the two side plates 16 and 17 of the frame. Each bearing 47 is secured to the associated side plate, as, for example, by nut and bolt combinations indicated by the reference numeral 48. Thus, turning of the operating shaft 46 results in turning movement of the two spur gears 44 and 45 and movement of the racks and the door plate in one direction or the other, depending, of course, on the direction of rotation of the shaft 46. To enable the operating shaft 46 to be turned, a socket 49 is secured to each end thereof. Each socket 49 has at least one opening 51 formed therethrough so that a trainman may insert a bar in an opening 51 in order to turn the shaft 46.

The lock mechanism 13 comprises a latch rod 56 which extends laterally between the two side plates 16 and 17. The rod 56 extends transversely or normal to the direction of movement of the plate 11 and is above the path of movement of the door plate 11, as shown in FIG. 2. The ends of the latch rod 56 are rotatably supported by a pair of bearing brackets 57 and 58 which are secured, as by welding, to the rearwardly extending end portions of the two side plates 16 and 17. As shown in FIGS. 2 and 4 through 8, the upper sloping portions of the two side plates 16 and 17 are cut away, as at 60, rearwardly of the rear plate 26 to provide clearance for the lock mechanism 13. The bearing brackets 57 are located such that the latch rod 56 is spaced a short distance rearwardly of the adjacent ends of the two racks 41 and 42 when the plate 11 is closed.

The lock mechanism 13 further includes two latches 61 rigidly secured to the latch rod 56, each of the latches 61 being located generally in alignment with one of the racks 41 and 42. Each latch 61 is secured to the latch rod 56 as by forming an indentation 62 in the lower edge thereof, positioning the latch perpendicularly to the rod 56 with the rod 56 in the indentation 62, and welding the latch to the rod. The indentation 62 of each latch is located closer to one end of the latch than the other, thus forming a relatively long "notched end" 61a (FIGS. 6 to 8) and a relatively short "trip end" 61b. The latch 61 shown in FIGS. 1, 4 and 6 is in its "engaged" position where the notched end 61a slopes downwardly and forwardly from the latch rod 56, and a notch 63 in the end 61a engages the rearward end of the associated rack. As best seen in FIG. 6, the notch 63 forms a horizontal edge 64 which is supported on the upper surface of the rack and a vertical edge 65 which extends downwardly behind the end of the rack. Thus, the edges 64 of the notches support the two latches on the racks and the edges 65 prevent rearward movement of the racks when the latches are engaged.

To disengage the lock mechanism, the latch rod 56 is pivoted in the clockwise direction, as viewed in FIG. 6, to move the two latches 61 to their "disengaged" positions shown in FIG. 7. A handle 67 (FIGS. 1 and 6 through 8) is rigidly secured to each end of the latch rod 56 on the outside of the associated bearing bracket 57 and 58 so that the rod 56 may be manually turned. In the present instance each handle 67 comprises a flat elongated bar which is positioned normal to the rod 56 and has one end portion secured to the end of the rod. The opposite end of the handle is bent laterally outwardly, as shown in FIGS. 1 and 5, and serves as an operating portion or crank. Further, the bearing brackets 57 and 58 also have the rearward ends thereof turned laterally outwardly, as at 57a and 58a, and when the rod 56 is turned to move the latches 61 to their fully disengaged position, the outwardly bent ends of the handles 67 rest against the outturned ends 57a and 58a of the bearing brackets 57 and 58 (FIG. 7).

It will be noted from FIG. 7 that when the latches are in their disengaged positions the center of gravity of the assembly, including the two latches 61 and the two handles 67, is rearwardly, or to the right of, the axis of rotation of the rod 56, and consequently gravity tends to hold the latches 61 in their disengaged positions once they have been placed there. On the other hand, when the latches 61 are placed in their engaged positions, shown in FIG. 6, the center of gravity of this assembly is forwardly of the axis of the rod 56, and consequently gravity also tends to hold the latches 61 in the engaged positions once placed there.

When the door plate 11 is closed and the latches are disengaged, the latches 61 extend substantially vertically and the trip ends 61b extend downwardly from the rod 56 into the paths of movement of the racks. Consequently, movement of the door plate 11 out of the closed position and toward the right, as seen in FIG. 7, results in the racks striking the trip ends 61b when the racks reach the dashed line position shown in FIG. 7. The racks move the latches to the "tripped" position illustrated in FIG. 8 where the notched ends 61a of the latches are supported on the upper surface of the door plate 11. Subsequent movement of the door plate 11 toward the left to its closed position results in the ends 61a sliding over the end portion 36 of the plate and the blocks 50 and then dropping downwardly into engagement with the rearward ends of the racks to the "engaged" position of FIG. 6.

When a hopper car including a discharge gate of the foregoing character is to be loaded, the door plate 11 is first moved to its closed position and the lock mechanism 13 is turned to engage the latches 61 with the racks (FIGS. 1, 2 and 6). When the hopper car is loaded the discharge gate may be sealed by threading a wire or band seal (not shown) through holes 76 and 77 formed in at least one of the handles 67 and the adjacent bearing bracket 57 or 58, the holes 76 and 77 being in alignment, as shown in FIG. 6, when the lock mechanism is engaged.

To discharge the contents of the hopper car, the seal is removed and, by turning one of the two handles 67, the latches 61 are pivoted clockwise to their fully disengaged position, as shown in FIG. 7. A bar (not shown) is inserted into one of the openings 51 in a handle socket 49, and the operating shaft 46 is turned to move the door plate 11 toward its open position. Movement of the door plate toward the open position causes the rearward ends of the two racks to strike the trip ends 61b of the two latches 61 and pivot the latches 61 to the tripped position, shown in FIG. 8. Subsequent movement of the door plate 11 to the closed position results in the notched ends 61a of the two latches 61 dropping into their fully engaged positions. Even if the door plate 11 were moved to its fully closed position and the latches were left in the disengaged position, the latches would automatically be tripped by shifting of the door plate 11 when the hopper car is moved, as during switching. For example, sharp movement of the car toward the left, as seen in FIG. 7, would cause the door plate 11 to shift toward the right and trip the latches. Subsequent slowdown of the car would cause the door plate 11 to shift to the left, and the latches would then immediately drop into the engaged position and prevent further movement of the door plate 11.

From the foregoing description, it will be apparent that a novel lock mechanism for a discharge gate of a hopper car has been provided. The mechanism is very simple and rugged in construction, which is an extremely important feature in a railway car. Further, the mechanism is both manually engageable and self-engageable in response to shifting movement of the door plate 11. Consequently, damage to the discharge gate or loss of the door plate is prevented even though a trainman neglects to engage the lock mechanism.

Claims

I claim:

1. A lock mechanism for a hopper car discharge gate of the type having a frame and a door plate supported on said frame for horizontal sliding movement between an open position and a closed position, said lock mechanism comprising an elongated latch, and a rod extending transversely through and supporting said latch intermediate its ends for rotation between an engaged position, a generally horizontal tripped position and a generally vertical disengaged position, said latch including a latch portion which when said latch is in said engaged position engages and holds the plate in its closed position and when said latch is in said disengaged position permits movement of the plate, said latch also including a trip portion which extends into the path of movement of the plate when the plate is in its closed position and said latch is in said disengaged position, said trip portion being shorter than said latch portion and disposed to be struck by the plate upon sliding of the plate toward its open position thereby rotating the latch away from said disengaged position to said tripped position in which said latch portion rests on said plate and is in position for subsequent movement into said engaged position upon return of the plate to its closed position.

2. A discharge gate and lock assembly for a hopper car having a discharge opening on the underside thereof, said assembly comprising a frame adapted to be attached to said car at said opening, a plate mounted on said frame for generally horizontal movement between a closed position where it covers said opening and an open position where it uncovers said opening, a latch rod pivotally mounted on said frame and extending generally transversely of the direction of movement of said plate, a handle on each end of said latch rod adjacent a side of said frame, and an elongated latch on said rod adjacent said plate, said latch being rotatable by turning either one of said handles between an engaged position in which one end portion of said latch engages and holds said plate in said closed position and a disengaged position in which the one end portion extends upwardly from the rod and permits opening movement of said plate and the opposite end portion of said latch extends downwardly from the rod in the path of movement of a portion of said plate and movement of said plate toward its open position resulting in said portion of said plate striking said opposite end portion and tripping said latch from said disengaged position toward said engaged position, said latch being positioned on said rod relative to said handles to be pulled by the weight of said handles and said one end portion into said engaged position after the tripping of said latch when said plate is returned to closed position.

3. An assembly as in claim 2, wherein said one end portion of said latch and said two handles are on one side of the axis of said rod when the latch is in said engaged position and said handles are shifted to the other side of said axis when said latch is moved to said disengaged position, whereby gravity tends to hold said latch in whichever engaged or disengaged position it is placed and to move said latch from a tripped position to said engaged position when said plate is moved to the closed position.

4. An assembly as in claim 2, wherein said other end portion of said latch when in said disengaged position extends downwardly into said path of movement of said portion of said plate to be struck and rotated to a tripped position upon movement of said plate toward said open position, said one end portion of said latch resting on the upper surface of said plate when in said tripped position and until said plate moves into said closed position.