Hatch cover structure

A plastic hatch cover is secured over a hatch opening by a hold-down bar extending across the hatch opening above the hatch cover. The hold-down bar has one end pivotally connected with a hinge bracket on the upper deck and another end engageable with a latch structure for sealing the hatch cover. The hatch cover is secured to the hold-down bar by clips on the hold-down bar adjacent the latch structure and adjacent the hinge. The clip adjacent the hinge detaches from the rest of the hold down bar when the hinge bolt is withdrawn, allowing removal of the hatch cover. Lug portions extend upwardly from the hatch cover to engage the hold-down bar to prevent lateral motion of the hatch cover with respect to the hold-down bar. The hatch cover is provided with reinforcing webs on its upper surface and on its lower surface.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an apparatus for the securement of a hatch cover 
over an opening, particularly an opening in a railroad hopper car. 
2. Description of the Prior Art 
Numerous designs exist in the prior art for securing a hatch cover over an 
opening in a railway car. However, the hatch covers in the prior art are 
generally constructed from relatively expensive materials, making 
replacement of the hatch covers costly. Also, replacement of the hatch 
cover in these designs is generally rendered difficult by the hatch cover 
being rigidly affixed to the rest of the hatch sealing apparatus. Some 
designs, such as U.S. Patent Nos. 4,179,999 and 4,248,160, have disclosed 
apparatus for sealing a hatch cover over an opening wherein the hatch 
cover has mounting flanges thereon for hinged mounting of the cover to the 
body of the railway car. These mounting flanges are vulnerable to damage. 
SUMMARY OF THE INVENTION 
The present invention provides for a hatch cover sealing apparatus wherein 
the hatch cover may be readily replaced. The hatch cover is composed of 
relatively inexpensive plastic material, and is retainingly engaged with a 
locking bar which extends across a coaming in a hopper car and is 
pivotally associated with the opening. A simple arrangement for 
entrappingly securing the hatch cover to the locking bar is provided. 
The hatch cover is secured only to the locking bar, and the pivot mounting 
flanges, which would be especially vulnerable in a plastic hatch cover, 
are eliminated. 
Further objects and advantages of the invention will be disclosed 
hereinafter in the specification, and the scope of the invention will be 
articulated in the claims.

Description of the Preferred Embodiment 
As best shown in FIGS. 1 and 2, a railway hopper car or other container has 
an upper deck surface or deck means 9 having a hatch ring or annular 
coaming 10 extending vertically upward therfrom and defining a hatch 
opening in the deck surface 9. This opening is closed by hatch cover 11 
which is sized to cover the opening. A seal is maintained by hatch cover 
gasket 12 held between hatch cover 11 and coaming 10. 
Hatch cover 11 is secured over coaming 10 by hold-down bar or retaining 
member 15 which extends across the top of hatch cover 11. One end of the 
hold-down bar 15 is operatively associated with the hinge structure 
generally designated at 16. Hinge structure 16 includes hinge bracket 17 
rigidly affixed to coaming 10. Pivot pin means or bolt 19 pivotally 
connects hold-down bar 15 with bracket 17. 
The end of the hold-down bar 15 distal to the hinge structure 16 is 
provided with latching portion 21 which is engageable with the latching 
structure generally designated at 23. Latching structure 23 may be engaged 
with latching portion 21 to cammingly press latching portion 21 downward, 
securing the hold-down bar 15 across the coaming and applying downward 
force on the cover 11 to seal it over the coaming 10. Latching structure 
23 may be pivoted to unseal the hatch cover 11 and will retain the cover 
11 in a blow-off position, restricting movement of the cover 11 but 
allowing pressure in the railway car to escape between the coaming 10 and 
the cover 11. Latching structure 23 may be pivoted completely clear of the 
latching portion 21 and away from the coaming 10 to be supported above the 
deck surface 9, as shown in FIG. 3. With the latching structure 23 in this 
position, the cover 11 is free to pivot fully away from the coaming 10. 
The latching structure 23 shown in the preferred embodiment is similar to 
that disclosed in U.S. Pat. application Ser. No. 679,287, filed Dec. 7, 
1984, now U.S. Pat. No. 4,655,365, and titled "HATCH COVER LOCK", which is 
hereby incorporated by reference. However those skilled in the art will 
realize that a variety of other securing arrangements may be provided to 
restrain the hold-down bar 15 against movement away from coaming 10. 
As is visible in FIG. 3, when the hold-down bar 15 is released and pivoted 
away from the coaming 10, the hatch cover 11 moves with the hold-down bar 
15, uncovering the opening. Rotation of the hold-down bar 15 continues 
until the fully opened position shown in FIG. 4 is reached, wherein the 
hatch cover 11 has been moved fully away from the coaming 10. 
Hatch cover 11 is secured to hold-down bar 15 by entrapment means. The 
entrapment means comprises first cover clip means 25 extending through 
first recess or opening 27 in the hatch cover 11 adjacent the hinge 
structure 16, and second cover clip means or hook 31 connected to 
hold-down bar 15 extending downwardly therefrom and through second recess 
or opening 33 in hatch cover 11 adjacent the latching arrangement 23. 
Clip means 31 and 25 extend through recesses 33 and 27 in hatch cover 11 
and prevent hatch cover 11 from becoming separated from hold-down bar 15 
by vertical and lateral movement with respect thereto. Hatch cover 11 is 
also secured against lateral movement with respect to hold-down bar 15 by 
stop means comprising a pair of lug portions 35. One of the lug portions 
35 extends upwardly from the hatch cover 11 on each side of the hold-down 
bar 15. 
In the sealed position, hold-down bar 15 engages the hatch cover 11 only at 
center area 36, distributing an equal load about the perimeter of the 
hatch cover 11 above the gasket 12. During the operation of uncovering the 
opening, the only contact between the hatch cover 11 and the hold-down bar 
15 is at recesses 27 and 23 and with the lug portions 35, securing the 
cover 11 to move in concert with hold-down bar 15. 
The hatch cover provided with this invention is adapted to be readily 
replaced. In the preferred embodiment a high-impact styrene plastic 
material is used for the hatch cover, although those skilled in the art 
will readily see that other materials, as well as other designs of hatch 
cover, might be used without departing from the scope of the invention. 
The hatch cover 11 of the preferred embodiment is disclosed in FIGS. 6,7, 
and 8. As best shown in FIG. 6, the upper surface 38 of the hatch cover 11 
is provided with sixteen exterior reinforcing webs or ribs 37 extending 
upwardly from the upper surface 38 of the hatch cover 11 and radially 
outwardly from the center area 36 of the hatch cover 11. Each web 37 is 
oriented at 221/2.degree. relative to the adjacent web 37. 
The central web 37a extends across the cover 11 between recesses 27 and 33, 
and between lug portions 35 below hold-down bar 15. Central web 37a 
extends upward and terminates below the height of center area 36 to 
accommodate hold-down bar 15 which engages center area 36 during sealing. 
The first webs 37b adjacent central web 37a are formed as radially 
extending extensions of lug portions 35. The remaining webs, indicated by 
reference character 37c extend radially outwardly from the outer surface 
of lug portions 35. 
The inner surface or underside 40 of hatch cover 11 is provided with 
interior reinforcing webs or ribs 39 extending downwardly from the inner 
surface 40. The eight interior webs 39 extend radially away from center 
structure 42 and are spaced at angular intervals of 45.degree.. Interior 
webs 39 terminate at reinforcing ring or annular member 43, which is 
spaced radially inwardly of the perimeter of cover 11 to accommodate 
sealing gasket 12 supported adjacent the perimeter of cover 11. 
Reinforcing webs 37 and 39 serve to structurally strengthen the flattened 
conical shape of the hatch cover 11. This is desirable when the hold-down 
bar 15 is secured by latching mechanism 23, applying downward force at the 
center area 36. This downward force is transmitted radially outwardly 
through the body of the hatch cover 11 and through the reinforcing webs 37 
and 39 to the outer perimeter of the hatch cover 11 to result in a 
downward sealing force on gasket 12 and coaming 10. 
Loadings are also created in the cover 11 by forces near the perimeter of 
the cover 11 tending to rotate the cover 11 about an axis parallel to the 
hold-down bar 15. These forces are resisted by the lug portions 35 
engaging the hold-down bar 15 and the recesses 27 and 33 engaging the clip 
means 25 and 31. The portion of the hatch cover 11 between the point of 
applied force and the point of the reaction force at recesses 27 and 33 
and lug portions 35 acts as a moment arm, and the cover 11 is rigidified 
in this role by reinforcing webs 37 and 39. 
The use of first and second clip means 25 and 31 to support the hatch cover 
11 eliminates the hinge mounting flanges of prior art hatch covers. The 
elimination of mounting flanges is particularly beneficial where the hatch 
cover is formed of plastic material, which would be especially vulnerable 
to cracking in the hinge flanges. 
Replacement of the hatch cover 11 is effected by removing pivot bolt 19 
which allows hinge structure 16 to be disassembled as shown in FIG. 5. As 
best shown in FIG. 5, hold-down bar 15 includes hinge channel portion 44. 
Hinge channel portion 44 includes central web 46 and downwardly extending 
side flanges 48. Flanges 48 are each provided with openings 50 therein for 
receiving pivot bolt 19. Hold-down bar 15 also includes clip portion 54 
supporting clip means 25. Clip portion 54 has a central wall portion 56 
extending laterally with respect to hold-down bar 15, and flange portions 
58 extending longitudinally with respect to the hold-down bar 15 from the 
lateral ends of the wall portion 56. Flange portions 58 are provided with 
openings 60 for receiving pivot bolt 19. 
In the assembled condition shown in FIGS. 1 and 4, flanges 48 of hinge 
channel portion 44 extend between flange portions 58 of clip portion 54. 
The inward ends 61 of flanges 48 of channel portion 44 engage wall portion 
56 of clip portion 54, and bolt 19 extends through openings 50 and 60. As 
a result, relatively little relative motion between clip portion 54 and 
hinge channel portion 44 is possible, and clip portion 54 pivots with the 
rest of hold-down bar 15 when hold-down bar 15 is pivoted toward and away 
from the coaming 10. 
In the fully open position shown in FIG. 4, hinge channel portion 44 
engages hinge stop means 62 supported between vertical flanges 63 of hinge 
bracket 17. This prevents rotation of the hold-down bar 15 beyond the 
fully open position, and prevents the hold-down bar 15 from impacting the 
upper deck surface 9. 
Hatch cover 11 is entrapped by first clip means 25, second clip means 31, 
and lug portions 35 to move with hold-down bar 15. When bolt 19 is 
removed, clip portion 54 separates from channel portion 44 of the 
hold-down bar 15, which may be moved upward and away from the hinge 
structure 16. This withdraws hold-down bar 15 from between the lug 
portions 35. Hatch cover 11 is also permitted to move longitudinally with 
respect to locking arm 15 when clip portion 54 is detached. Longitudinal 
movement moves recess 33 away from second clip means 31 at the distal end 
of the hold-down bar 15, fully disengaging the hatch cover 11 from locking 
arm 15. 
A new hatch cover may be engaged with hold-down bar 15 by slipping recess 
33 of the hatch cover 11 over second clip means 31. The hatch cover 11 is 
symmetrical, so that either of the recesses may be fitted over second clip 
means 31 with the same result. The hatch cover 11 is moved towards 
hold-down bar 15 to receive hold-down bar 15 between its lug portions 35. 
Clip portion 54 is fitted over the channel portion 44, causing clip means 
25 to enter recess 27 in the hatch cover 11. The combined hatch cover and 
hold-down bar structure is inserted between generally vertical flanges 63 
of hinge bracket 17 until openings 50 and 60 align with openings 70 in 
hinge bracket flange 63. Pivot bolt 19 is inserted through openings 50, 60 
and 70 and secured therein by securing means or nut 73, completing the 
operation of replacement. 
The foregoing description and drawings merely explain and illustrate the 
invention, and the invention is not limited thereto except insofar as the 
eppended claims are so limited, as those skilled in the art who have this 
disclosure before them will be able to make modifications and variations 
therein without departing from the scope of the invention.