US3789776A - Hopper car hatch cover and lock assembly - Google Patents

Abstract

A hatch cover and lock ring assembly is provided for use in sealing the hatch of a pressurized railroad hopper car, with the cover in sealing engagement with the upper lip of the coaming. There is a circular cover hingedly attached to the railroad car and having an elastomeric gasket attached to the bottom surface of the cover, adjacent its periphery to be compressible between the cover and the upper lip. An annular lock ring having end portions and a generally U-shaped cross section is held by retaining means in a uniform spaced relationship with respect to the cover. An over-center clamp mechanism is connected to the end portions of the lock ring and when locked, it draws the lock ring into tight sealing engagement about the cover and upper lip causing the cover to approach the upper lip, compressing the gasket therebetween for an air-tight uniform seal. The cover and lock ring assembly enables the use of a cover made from fiber reinforced plastic (FRP), rather than a heavier and more expensive aluminum or stainless steel casting, with improved sealing capability and less labor time and skill.

Description

United States Patent 1191 Funkey Feb. 5, 1974 HOPPER CAR HATCH COVER AND LOCK [57] ABSTRACT ASSEMBLY A hatch cover and lock ring assembly is provided for [7 51 Inventor; Donald J. Funkey, Ionia Mich use in sealing the hatch of a pressurized railroad hopper car, with the cover in sealing engagement with the [73] Assrgnee; The General Tire & Rubber upper lip of the coaming. There is a circular cover Company Akron Ohio hingedly attached to the railroad car and having an [22] Filed; No 7, 1972 elastomeric gasket attached to the bottom surface of the cover, adjacent its periphery to be compressible PP N05 304,445 between the cover and the upper lip. An annular lock ring having end portions and a generally U-shaped [52 US. Cl. 105/377 Cross Section is held by retaining means in a uniform 51 1m. (:1 B6ld 39/00 Spaced relationship With respect to the cover [58] Field of Search 105/377; 220/24 over'cehtei clamp mechanism is to the end portions of the lock ring and when locked, it draws the [56] References Cited lock ring into tight sealing engagement about the UNITED STATES PATENTS cover and upper l1p caus1ng the cover to approa f:h the 1,747,591 2/1930 Moore 220/46 fi 1 gasket jf i or an 2,572,963 10/1951 Wily 105/377 2 12 i:; 1 g 2$:$ 3,664,270 5/1972 Stark et a1. 105/377 Primary Examiner-Robert G. Sheridan Assistant Examiner-Richard A. Bertsch forced plastic (FRP), rather than a heavier and'more expensive aluminum or stainless steel casting, with improved sealing capability and less labor time and skill.

PATENTED E 51974 SHEEI 1 0F 4 FIG! PATENTEB FEB 74 SHEET 3 BF 4 FIG. 4

FIG. 5

HOPPER CAR HATCH COVER AND LOCK ASSEMBLY BACKGROUND OF THE INVENTION This invention relates to railroad cars and, more particularly, to hatch cover and locking assemblies for railroad hopper cars.

For many uses of railroad hopper cars it is desirable to pressurize the car so that, for example, dust and dirt in the air are unable to get inside the car and contaminate the contents, such as plastic pellets covered with a layer of inert gas; Hatch covers for pressurized cars typically have a nominal diameter (measured by the ID. of the coaming" or hatch) of inches. Using a cover of that size, under pressure, results in problems in the attempt to effectively seal the hatch.

Conventionally, the covers have been cast aluminum or cast stainless steel, held down by three or more threaded hand wheels.'The use of more than three hand wheels is an attempt to eliminate the problem of uneven sealing pressure (a good seal adjacent the hand wheels and a poor seal between the wheels). To improve the sealing capability, the covers were made thicker and more rigid, thus increasing their material cost. In an effort to reduce the excessive material cost of the cover, the prior art hatch covers were made from fiber reinforced plastic (FRP), but it was found not to be economically feasible to make FRP covers which would be rigid enough to prevent leakage from the hatch. By necessity, therefore, railroad car manufacturers have continued to make the hatch covers from aluminum or stainless steel castings and the continued use of the hand wheel sealing apparatus involves additional problems, of the type normally anticipated where it is necessary to constantly run a threaded member into and out of another member having internal threads. Not only do the threaded portions corrode, jam and cross-thread, but also a considerable amount of time, skill and care are required to run-down the series of threaded hand wheels so that the seal pressure is as uniform as is possible with such a cover and lock arrangement, while not damaging the gasket. It is most advisable to tighten the wheels alternately and in stages as is done with the lug-nuts for an automobile wheel.

The concern over the prevention of dirt getting to the contents of the hopper car is well illustrated by the procedure followed when the contents are unloaded. Before the underside of the car is opened to permit removal of the contents, filters are placed over the tops of the hatches to prevent dirt from being sucked in by the partial vacuum created as the material is dumped from the bottom of the hopper. Therefore, it can readily be appreciated that the ability to lock and unlock the hatch cover quickly is of importance to the railroads.

SUMMARY OF THE INVENTION It is a further object of the present invention to provide ahatch cover and'lock assembly which makes it possible to seal the hatch with more uniform pressure around the periphery of the cover.

It is also an object of the present invention to provide an apparatus whereby it is possible to lock and unlock the hatch cover much more quickly than in the past.

It is another object of the present invention to provide a locking assembly for a railroad hatch cover which eliminates the use of threaded members and the related problems.

In accordance with these and other objects of the present invention, a hatch cover and lock assembly is provided which can be advantageously used to seal the hatch of a pressurized railroad hopper car, with the cover in sealing engagement against the upper lip of the coaming. The cover is preferably a circular member having oppositely disposed top and bottom surfaces and including means for hingedly attaching the cover to the car. An elastomeric gasket is attached to the bottorn surface of the cover, adjacent its periphery and located to be compressible between the cover and the lip. A generally annular lock ring is positioned about the periphery of the cover and has a pair of end portions and a generally U-shaped cross section with oppositely disposed top and bottom flanges diverging. As the lock ring closes about the cover, the top flange slidingly engages the peripheral portion of the top surface of the cover and the bottom flange slidingly engages the underside of the upper lip, causing the cover to approach the lip and compressing the gasket therebetween. There are means attached to the end portions of the lock ring for clampingthe lock ring into tight sealing engagement about the periphery of the cover. Also provided is means for movably mounting the lock ring in a substantially uniform spaced relationship with the cover while allowing for generally radial movement of the lock ring with respect to the cover member. Because of the disclosed cover and lock ring arrangement, it is possible to quickly andreliably seal the hatch in such a way that there is uniform pressure on the gasket around the periphery of the hatch.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the hatch cover and lock assembly of the preferred embodiment of the present invention in a locked position;

FIG. 2 is a cross section taken on line 22 of FIG. 1;

FIG. 3 is a fragmentary plan view of the preferred embodiment of the present invention in an unlocked position, onthe same scale as FIGS. 1 and 2;

FIG. 4 is a fragmentary plan view showing the lock ring in an open position, on the same scale as FIGS. 13;

FIG. 5 is a cross section similar to FIG. 2, butvon a larger scale, showing the lock ring in an open position;

FIG. 6 is a cross section taken on line 6-6 of FIG. 1, but on the same scale as FIG. 5;

FIG. 7 is a cross section taken on line 77 of FIG. 1, on the same scale as FIGS. 5 and 6;

FIG. 8 is a cross section taken on line 8-8 of FIG. 1, on the same scale as-FIGS. 5-7.

DESCRIPTION OF A- PREFERRED EMBODIMENT Referring specifically to the drawings which are for the purpose of illustrating a preferred embodiment of the present invention and not for the purpose of limiting the same, FIG. 2 illustrates the manner in which the hatch cover and lock assembly are employed to seal the hatch of a pressurized hopper car. The hatch opening is defined by the coaming 12 which includes a vertical cylindrical wall 14 terminating in an outwardly turned upper lip 16. It is the inside diameter of cylindrical wall 14 which defines the nominal diameter of the hatch cover.

The Cover and Lock Ring Assembly The hatch cover and lock ring assembly comprises a circular cover member having a top surface 22. The cover member 20 is preferably relatively thin, deriving the necessary rigidity from a plurality of radially extending reinforcing ribs 24, and a cylindrical reinforcing rib 26 which is concentric with the periphery 29 of the cover 20. In the subject embodiment, the cover '20 is made from a fiber reinforced plastic (FRP), and more specifically, from a fiberglass reinforced polyester resin, which can easily and economically be fabricated into the illustrated configuration by means of matched-metal molds, in which case the cover 20 and the reinforcing ribs 24, 26 can be molded integrally for desirable rigidity and good wear properties.

As is shown in FIG. 5, an elastomeric gasket 30 is attached to the underside surface 28 of the cover, to be compressed between the surface 28 and the upper lip 16 of the coaming 12. Preferably, reinforcing rib 26 is disposed in a closely spaced relationship with, and inward of, the wall 14 so that a portion of the gasket 30 will be compressed between rib 26 and wall 14. The gasket 30 has a configuration which defines enclosed annular voids 32, 34 and allows the cover to move either horizontally or vertically without stressing the bond between the cover and the gasket material. The gasket 30 may be fixedly attached to the cover with a glue, and the gasket is preferably extruded from an elastomeric material, for example, neoprene and spliced.

The entire cover and lock assembly is attached to the railroad car only by means of the hinge butt 40, having an end portion 42 attached to the cover 20 by three rivets 44, each retained by a collar 46. The opposite end of the hinge is a hinge leaf 47 terminating in a generally cylindrical portion 48 which is restrained by a pin 49 attached to the railroad car. The opening in end portion 48 is substantially larger than the pin 49, thus allowing the cover assembly to move horizontally and self-center within the coaming, or move vertically to allow for sealing adjustment.

The lock ring 50 comprises an elongated member formed into a generally annular shape, and having a length just slightly less than enough to fit around the entire periphery of the cover. The lock ring 50 has a cross section which is roughly a U-shape including a top flange 52 and a bottom flange 54. In addition, the lock ring terminates in end portions 55, 56, having the same cross sections as the remainder of the lock ring. End portions 55, 56 of lock ring 50 are fixedly attached, such as by welding, to pivot brackets 57, 58 respectively.

As is best shown in FIGS. 1, 3 and 6, lock ring 50 is controlled, through pivot brackets 57, 58, by a mechanism 60, hereinafter referred to as an over-center clamp,- which comprises a top link 62, a bottom link 64,

a handle member 66 and three. rivets 68. Pivot bracket 57 is connected to the left end of the assembly of top link 62 and bottom link 64, while the pivot bracket 58 is connected to the end of handle 66.

When the over-center clamp 60 is in a locked position, as shown in FIG. 1, there is tension therein tending to force the handle 66 radially outward toward the open position. To prevent this, a lock bracket 70 is provided and welded, or attached by other means, to the lock ring, preferably on the outer surface of lock ring 50 as is best shown in FIG. 8. The lock bracket 70 terminatesvin an up-turned U-shaped portion 72 which serves to restrain the movement of handle 66. It may also be desirable to put overlapping slots in the lock bracket 70 and the handle 66, then insert a pin through the overlapping portions to further lock the handle in place.

Because it is desirable to maintain the lock ring and the cover member in an approximately uniformly, spaced relationship with respect to each other, a pair of retainer brackets has been provided, which serve as the only connection between the lock ring and the cover. The retainer bracket 80 includes a flat portion 82 and a contiguous arched portion 84, the underside of which is welded to the outer surface of top flange 52 of the lock ring. Within the flat portion 82 is an angled slot 86, which is restrained by bolt 88 so that the retainer bracket 80 can slide only in a rectilinear path (compare the views of the retainer bracket in FIGS. 1 and 4). The configuration of the bracket 80 and the angle of the slot 86 should be such that as the lock ring moves away from the cover, the cover will remain centered within the lock ring, to facilitate opening of the cover.

While a wide variety of materials can be used for the parts described herein, all of the parts other than the cover 20 are preferably metal, such as chromium or zinc plated steel stampings, or more preferably, stainless steel.

Operation With the separate parts of the cover and lock ring assembly having been described, a detailed description of the method of-operation of the assembly will follow, in terms of closing and locking the cover, the position illustrated in FIGS. 1 and 2.-The fragmentary view in FIG. 3 shows an unlocked position of the handle 66 and over-center clamp 60, which serves the purpose of opening the lock ring 50, so that it can assume a spaced relationship with respect to the upper lip 16 when the cover is placed thereon, as can best be seen in FIG. 5. An additional view of the lock ring in its spaced position is presented in FIG. 4, with the retainer bracket 80 having slid to its outermost location. The handle 66 is then pivoted toward the cover, drawing the lock ring inward in a generally radial direction. As can best be seen by comparing FIGS. 2 and 5, the inside surfaces of top flange 52 comes into sliding engagement with top surface 22 of the cover at about the same time that the inside surface of bottom flange 54 comes into sliding engagement with the underside of upper lip 16. Because of the divergence of the flanges 52, 54, as the lock ring moves further inward after initial contact with the cover and the upper lip, the cover is forced to approach the upper lip, thereby compressing the gasket 30 until the lock ring, upper lip, cover and gasket are in the relative positions shown in FIG. 2, at which time the cover is sealed and locked. The locking is completed when the handle 66 is hooked into the U-shaped portion 72 of the lock bracket 70.

The use of the cover and lock assembly of the present invention makes it possible to retain the pressure within the hopper car. It has been difficult with the cover assemblies of the prior art, such as those described previously to retain even a relatively low pressure, whereas the present invention can generally retain a gauge pressure of at least 5 psi. Perhaps of even greater importance, the ability to retain pressure necessarily results in the ability to keep out dirt, as well as moisture.

Further, the use of the device described herein enables the operator to quickly lock or unlock the cover by merely pivoting the one handle member, without the need for the time, skill or care required to operate a series of hand wheels. The present invention also eliminates the problem of expensive damage resulting from unequal pressure on the gasket or corrosion or crossthreading of the threads.

Economically, the present invention provides a twofold cost savings. The seal arrangement employed permits the use of a thinner, less rigid cover, requiring less material, and therefore costing substantially less. In addition, while cast aluminum and stainless steel, as were used for the prior art covers, can still be used, it is now feasible to use an FRP such as fiberglass reinforced polyester resin as in the subject embodiment, thus resulting in a further saving in material cost.

Within the scope of the present invention, the various parts of the cover and lock assembly can have configurations other than those herein illustrated. The cross section of the lock ring may vary from that described, as long as it is able to act as a pressure wedge and force the cover and upper lip together.

Likewise, a different form of over-center clamp could be employed to clamp the lock ring about the cover and upper lip, or alternatively, another clamping means could be utilized if it can perform the function of quickly and tightly clamping the lock ring about the cover, in which ,case the handle and lock bracket would probably also be modified. It should also be clearly understood that an arrangement involving more than one lock ring could be used within the spirit of this invention, which could, of course, require more than one clamping means.

Modifications and alterations of the preferred embodiment will occur to those skilled in the art upon reading and understanding the specification, and it is intended to include all such modifications and alterations as part of the invention insofar as they come within the scope of the appended claims.

What is claimed is:

1. A hatch cover and lock assembly for use in sealing the hatch of a railroad hopper car, the hatch having a coaming including an upper lip, the assembly comprising, in combination;

a. a cover member having oppositely disposed top and bottom surfaces and including means for hingedly attaching said cover member to the car;

b. an elastomeric gasket fixedly attached to said bottom surface adjacent the periphery of said cover, located to be compressible between said cover and the upper lip;

c. a lock ring having a pair of end portions, said lock ring adapted to engage, the peripheral portion of said top surface and the underside of said upper lip, causing said cover to approach the lip, compressing said gasket therebetween;

d. clamping means attached to said end portions of said lock ring for clamping said lock ring into tight sealing engagement about the periphery of said cover; and

e. mounting means for movably mounting said lock ring in a substantially uniformly spaced relationship with said cover member, while allowing for generally radial movement of said lock ring with respect to said cover member.

2. The assembly of claim 1 wherein said cover is circular and said lock ring is generally annular and has a generally U-shapedcross section with oppositely disposed top and bottom flanges diverging and adapted to slidingly engage, respectively, the peripheral portion of said top surface and the underside of the upper lip.

3. The assembly of claim 1 wherein said clamping means comprises an over-center clamp and a handle member for actuating said over-center clamp. I

4. The assembly of claim 1 wherein said cover member is formed from a fiber reinforced plastic material and includes a plurality of integral reinforcing ribs.

5. The assembly of claim 1 wherein said mounting means comprises at least one retainer plate fixedly attached to said lock ring, slidingly engaging the top surface of said cover member and including a slot acting in cooperation with a bolt threaded into said cover member to limit the movement of said retainer plate to a linear path.

Claims (5)

1. A hatch cover and lock assembly for use in sealing the hatch of a railroad hopper car, the hatch having a coaming including an upper lip, the assembly comprising, in combination; a. a cover member having oppositely disposed top and bottom surfaces and including means for hingedly attaching said cover member to the car; b. an elastomeric gasket fixedly attached to said bottom surface adjacent the periphery of said cover, located to be compressible between said cover and the upper lip; c. a lock ring having a pair of end portions, said lock ring adapted to engage, the peripheral portion of said top surface and the underside of said upper lip, causing said cover to approach the lip, compressing said gasket therebetween; d. clamping means attached to said end portions of said lock ring for clamping said lock ring into tight sealing engagement about the periphery of said cover; and e. mounting means for movably mounting said lock ring in a substantially uniformly spaced relationship with said cover member, while allowing for generally radial movement of said lock ring with respect to said cover member.

2. The assembly of claim 1 wherein said cover is circular and said lock ring is generally annular and has a generally U-shaped cross section with oppositely disposed top and bottom flanges diverging and adapted to slidingly engage, respectively, the peripheral portion of said top surface and the underside of the upper lip.

3. The assembly of claim 1 wherein said clamping means comprises an over-center clamp and a handle member for actuating said over-center clamp.

4. The assembly of claim 1 wherein said cover member is formed from a fiber reinforced plastic material and includes a plurality of integral reinforcing ribs.

5. The assembly of claim 1 wherein said mounting means comprises at least one retainer plate fixedly attached to said lock ring, slidingly engaging the top surface of said cover member and including a slot acting in cooperation with a bolt threaded into said cover member to limit the movement of said retainer plate to a linear path.

Images