US3804028A

US3804028A - Apparatus for securing lading on railway flat cars

Info

Publication number: US3804028A
Application number: US00273231A
Authority: US
Inventors: J Hammonds; R Dare; Leary W O; D Thornton
Original assignee: ACF Industries Inc
Current assignee: ACF Industries Inc
Priority date: 1970-10-13
Filing date: 1972-07-19
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16

Abstract

A tie-down system for carrying loads, such as lumber, on the deck of a railroad car is disclosed having resiliently anchored banding providing tie-downs to secure the loads onto the deck so that a minimum travel or shifting of the loads longitudinally along the deck is obtained when the loads settle and impact forces are exerted against the car. The banding is arranged in an endless double loop over the load with the free ends of the bands positioned over the upper surface of the load for tensioning and securement. The double loop permits the banding to slip longitudinally about its anchor points thereby to provide a mechanical advantage and permitting a relatively high initial tensioning to be obtained with conventional tensioning equipment without the use of power tools. Various means are employed to reduce any pretensioning in the banding upon removal of the banding and unloading the flat car. The tie-down assembly is further designed to reduce or substantially eliminate lateral movement of the lading. The tie-down assembly comprises a resilient means for pretensioning the banding, a means for receiving the banding preferably designed to avoid stress concentrations in the banding passing therethrough, and means for providing at least some rotational movement of the tie-down assembly about its own generally vertical axis at least about 20*. Means may be provided on the car for storing the tie-down assembly when not in use. And the tie-down assembly may include means for mounting the same on the car in such a manner that upon removal of the banding therefrom, the assembly automatically assumes a stored position on the car.

Description

atent n91 llnited States ULeary et al.

[451 Apr. 16, 1974 APPARATUS FOR SECURING moms 0N RAILWAY lFlLAT CARS [75] Inventors: Walter E. OLeary, Creve Coeur;

Duane V. Thornton; James C.

Ellammonds, both of St. Charles; Roy R. Dare, OFallon, all of Mo.

[73] Assignee: ACF Industries incorporated, New

York, N.Y.

[22] Filed: July 19, 1972 [21] Appl. No.: 273,231

Related US. Application Data [63] Continuation-impart of Ser. No. 80,284, Oct. 13,

1970, Pat. NO. 3,678,866.

2,970,552 2/l96l Baker 105/368 T 3,298,l73 l/l967 Empson.... 105/369 A 3,229,952 l/l966 Zumbo 248/361 A 2,312,119 2/1943 Nystrom et al. 105/369 A Primary Examiner-Drayton E. Hoffman Attorney, Agent, or FirmHenry W. Cummings [57] ABSTRACT A tie-down system for carrying loads, such as lumber,

on the deck of a railroad car is disclosed having resiliently anchored banding providing tie-downs to secure the loads onto the deck so that a minimum travel or shifting of the loads longitudinally along the deck is obtained when the loads settle and impact forces are exerted against the car. The banding is arranged in an endless double loop over the load with the free ends of the bands positioned over the upper surface of the load for tensioning and securement. The double loop permits the banding to slip longitudinally about its anchor points thereby to provide a mechanical advantage and permitting a relatively high initial tensioning to be obtained with conventional tensioning equipment without the use of power tools. Various means are employed to reduce any pretensioning in the banding upon removal of the banding and unloading the flat car. The tie-down assembly is further designed to reduce or substantially eliminate lateral movement of the lading.

The tie-down assembly comprises a resilient means for pretensioning the banding, a means for receiving the banding preferably designed to avoid stress concentrations in the banding passing therethrough, and means for providing at least some rotational movement of the tie-down assembly about its own generally vertical axis at least about 20. Means may be provided on the car for storing the tie-down assembly when not in use. And the tie-down assembly may include means for mounting the same on the car in such a manner that upon removal of the banding therefrom, the assembly automatically assumes a stored position on the car.

28 Claims, 23 Drawing Figures PATENTED PR 1 IBM 3x30411328 sum 3 or a PATENTEUAPR 15 1974 sum 5 or 6 APPARATUS FOR SECURING LADING ON RAILWAY FLAT CARS CROSS REFERENCE TO RELATED APPLICATION BACKGROUND OF THE INVENTION Various types of tie-downs have been employed heretofore on railway flat cars to secure loads thereon. For example, chains have had their ends resiliently anchored over loads to hold the loads onto the deck of the car. However, prior art tie-downs employing banding are characterized in that only a relatively small amount of takeup is provided. Thus upon a settling or compaction of the load during transit, any pretensioning in the tie-downs is reduced or limited. The elimination or reduction in pretensioning permits the load to shift on the deck of the car, particularly during impacts. The shifting of the load is undesirable, particularly if a shift of over around 12 to 24 inches is permitted. Some shifting will probably result upon repeated impact loads being exerted against the car, particularlyrepeated impact loads from the same end, and as long as the shifting of the load is held within a minimum range then such shifting is not particularly harmful.

SUMMARY OF THE INVENTION The present invention is directed to a system of banding loads on flat cars and a tie-down assembly therefor so that a minimum shifting of the load results. The system employs a relatively high pretensioning of the banding over the load to be secured and such pretensioning is maintained, although at a lower level, even upon a compaction or settling of the load as much as 1.5 inches. The banding is arranged in an endless double loop over the lading which permits the banding to slip lengthwise and to provide a two to one mechanical advantage when the ends of the banding are drawn tight for pretensioning and securement. This permits conventional hand tools to be employed for drawing the ends of the banding tight and for supplying a pretensioning load of at least 2,000 preferably around 3,000 to 4,000 pounds. The resilient means preferably substantially ceases resilient deflection after the lading has travelled longitudinally on the car a maximum of about 24 inches.

A tie-down assembly is provided including resilient means to provide the necessary pretensioning, for example, a coil spring or rubber in shear; means for receiving the banding and applying the tension thereto preferably designed to avoid imparting stress concen-,

trations to the banding passing therethrough, such as a clevis or a link. In one embodiment part of the means for receiving-the banding is rotatable, for example, by providing a rotatable pin in a clevis. A collar may be provided on the pin to further avoid imparting stress concentrations to the banding passing therethrough. Means are also included in the assembly for allowing rotational movement of the assembly about its own generally vertical axis to the extent of at least about 20, and preferably allowing unlimited rotation about this axis.

The tie-down assembly is affixed to each side of the car and the banding extends about the banding receiving means with the ends of the banding positioned in overlapped fashion over the upper surface of the load. The ends of the banding are drawn tight and the resilient means on each side of the car is compressed to provide a pretensioning load on the associated banding.

Under high pretensioned loads, the cutting or snipping of the banding could be a safety hazard. Several separate embodiments are disclosed for reducing the tensioning in the banding prior to removal of the banding and unloading of the load.

The tie-down assembly may include meansfor mounting the assembly so that it automatically assumes a stored position on the car deck or adjacent the side of the car upon removal of the strapping therefrom. The car may contain means for supporting the assembly during transit when the assembly is not in use.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the claims which follow.

I THE DRAWINGS In the accompanying drawings, in which several of various possible embodiments of the invention are illustrated,

FIGS. 1 and IA are side elevations of a railway flat car illustrating bundled lumber secured thereon by the tie-down arrangement comprising the present invention, FIG. 1 showing one-half the length of the flat car and FIG. IA showing the other half of the length of the flat car;

FIG. 2 is an enlarged fragement of FIG. 1A showing the load and banding thereon'after the load has shifted longitudinally on the flat car;

FIG. 3 is an enlarged side elevation of the tie-down assembly device for tensioning the steel banding about the load on the flat car;

FIG. 4 is a side elevation of the tie-down assembly in a stored position along the outer surface of the side sill structure;

FIG. 5 is an end elevation of the tie-down assembly illustrated in stored position in FIG. 4;

FIG. 6 is a top plan of the banding arrangement over the upper surface of the load on the flat car indicating the end portions of the banding secured by a crimped connector;

FIG. 7 is an elevational view of a corner protector for the load over which the banding is positioned;

FIG. 8 is a modified form of the invention in which a separate banding loop is provided to release the tensioning of the banding for removal of the banding;

FIG. 8A is a further embodiment of the banding loop;

FIG. 9 is an end view looking along the side of the car of means to release the tension on the banding for removal of the banding and illustrates a gradual release of the pretensioned load;

FIG. 10 is a side elevation of the means for releasing tension shown in FIG. 9;

FIG. 11 is a section taken generally along line 1l11 of FIG. 10;

FIG. 12 is an elevation of a further form of means for releasing tensioning on the banding and illustrates an overcenter device;

FIG. 13 is a side elevation of the tensioning release means shown in FIG. 12.

FIG. 14 is a plan view illustrating another embodiment of the present invention with the tie-down assembly in the stored position; I

FIG. 15 is a side elevation of the embodiment shown in FIG. 14;

FIG. 16 is a view looking along the side of the car of the embodiment of the invention shown in FIGS. 14 and 15 with the tie-down assembly in operative position to secure the lading;

FIG. 17 is an enlarged view of the lading receiving means shown in FIG. 16 at 90 thereto;

FIG. 18 is a view looking along the side of the car of another embodiment of the present invention with the tie-down assembly in operative position to secure the lading;

FIG. 19 is a plan view of the embodiment shown in FIG. 18 with the tie-down assembly in the stored position;

FIG. 20 is a side elevation of the view in FIG. 19; and

FIG. 21 is an enlarged view of the lading receiving means in FIG. 18 at 90 thereto.

DETAILED DESCRIPTION Referring now to the drawings for a better understanding of this invention and more particularly to the embodiment shown in FIGS. 1-7, a railway flat car is generally indicated 10 having a center sill 12, a side sill structure generally indicated 14, and a deck 16 forming the upper surface of flat car 10. As shown particularly in FIGS. 4 and 5, side sill structure 14 comprises an outer angle 18 having an outer vertical leg 20 and a horizontal leg 22 to which deck 16 is welded. A vertical web 24 of side sill structure 14 has an outturned lower flange 26 at its lower end.

Mounted on deck 16 are a plurality of loads L comprising bundles oflumber banded together by bands B. Wooden transverse support members S are placed on deck 16 and between separate loads L of the banded lumber to space loads L from each other and from the deck to permit a forklift truck to load and unload the lumber from car 10.

Spaced along the length of flat car 10 are a plurality of tie-down assemblies generally indicated 28 and arranged in pairs aligned transversely of flat car 10. Each assembly 28 comprises a compression spring 30 mounted around a pair of

yokes

32 and 34. A follower 36 on the end of yoke 34 and a follower 38 on the end of yoke 32 engage opposite ends of spring 28 for compressing spring 30 upon outward movement of

yokes

32 and 34. A chain 40 has one end mounted about yoke 34 and has an end link 42 on its opposite end welded to the outer face of leg 20 thereby to prevent removal of compression spring assembly 28 from railway flat car 10. A link 44 connects yoke 32 with a clevis 46. Hooks 48 are secured to the outer face of vertical web 24 and are adapted to engage yokes 34 and clevis 46 as shown in FIGS. 4 and 5 for maintaining compression spring assembly 28 in a stored position when not in use.

To secure the bundles of lumber L onto the deck of flat car 10, a plurality of tie-downs are spaced along the length of car 10 each comprising an endless metal banding generally indicated 50 and positioned over loads L. Each endless looping of metal banding 50 is connected to a pair of compression spring assemblies 28. To mount metal banding 50 over loads L, a strip of metal banding is first positioned over the upper surface of the load and the free ends are threaded through clevises 46. The banding strip is then passed unwardly over load L with end portions overlapping each other over the upper surface of load L. In this position, metal banding 50 is ready to be tightened or tensioned. A conventional Windlass tensioning tool with a handle extension may be employed to pretension steel banding 50 to around 3,000 pounds. As an example, steel 0.035 inch thick with a breaking strength at around l2.000 pounds. After the banding has been pretensioned a predetermined amount, a splice or connector 52 is placed about the end portions of banding 50 and is crimped about the banding to hold the end portions of banding 50 together in a pretensioned relation. A crimping tool is best employed to crimp spice 52 about the banding.

To prevent steel banding 50 from damaging or biting into the corners of the bundled lumber, steel corner protectors 54 as shown particularly in FIGS. 6 and 7 are provided and have a central groove formed between raised portions 56 to receive banding 50.

As shown in FIG. 2, corner protectors 54 maintain the banding spaced as it passes from the top of the lading to clevis 46. This spacing applies a moment to clevis 46 urging the same to rotate during tightening of the banding. If the assembly 28 could not rotate to accommodate this moment, stress concentrations would be introduced into the banding by clevis 46 which would sometimes lead to failure of the banding. However, the links of chain 40 provide the desired rotational freedom which has been found to be at least about 20.

As an example of spring assembly 28, spring 30 may be a length of 12 inches and have a total compression of around 3 inches with a spring rate of L500 pounds per inch of compression. Thus, to obtain a tensioning of 3,000 pounds in banding 50, spring 30 would be compressed 2 inches which would leave 1 inch of compression remaining after pretensioning of bands 50. Thus, even if loads L compacted or settled as much as (1 /2) some pretensioning, about 750 pounds, would r'er'iiinin banding 50 Eur ther, springs 30 would not bottom out until the total 3 inch travel had been effected in spring 30. As end bulkheads are not provided to restrain the longitudinal shifting of loads L, it is desirable that the longitudinal shifting be minimized particularly to repeated impact loads from the same end. The amount of restraint by the tie-down would be dependent on the total number of tie-downs and on the amount of cushioning the flat car has. For example, with only conventional draft gear employed, the spacing of the tie-downs would be relatively small while with along travel end of car cushioning unit, such as a cushioning unit at each end of the car having a travel of 15 inches, a relatively large spacing between the separate tie-downs for the loads might be provided.

As a specific example, a flat car 89 feet in length was loaded with l65,000 pounds of finished pine lumber consisting of bundles 2 feet by 4 feet in lengths of 8 feet, 10 feet, 12 feet, 14 feet, 18 feet and 20 feet. The flat car employed end of car. cushioning with a 15 inch travel. Steel banding was applied using 1 inch wide by 0.035 inch thick banding as shown in FIGS. 1-7 and the banding was tensioned to around 3,000 pounds. Chain 40 contained 12 links allowing 27 of rotation of assembly 28 about its generally vertical axis. Seventeen tie-downs were spaced around 4.5 feet apart along the length of the railway flat car and the car was impacted by three repeated miles per hour impacts with a 220,000 pounds striking car and no backup cars. A total average load shift of around 12 inches was obtained and none of the tie-downs exceeded 80 percent of their breaking strength during the three high speed impacts from the same end.

Thus, the present banding arrangement permits the banding from going slack even with a settlement of the load in transit and thereby minimizes any undue shifting of loads L. A tension is maintained on the load under substantially all conditions and lengthwise shifting of loads L on the car, particularly where long travel end-of-car cushioning devices are provided, is within acceptable limits. The arrangement of the banding in an endless double loop arrangement permits the banding to slip lengthwise upon tightening, thereby providing a two to one mechanical advantage which permits a conventional tensioning tool to be employed for providing a 3,000 pounds pretensioning on each of the tiedowns. The two strands or passes of the banding over the upper surface of the load are laterally spaced from each other and two corner protectors 54 are positioned over each upper corner of the load which also facilitates the slipping of the banding lengthwise upon pretensioning. It is noted that the amount of pretensioning may be determined visually by inspecting the amount of deflection in spring assemblies 28.

In general, the spring should be capable of being tensioned to at least about 2,000 pounds, preferably to at least about 3,000 pounds. The spring should be capable of retaining a minimum of at least 750 pounds after load settlement. This should be the case even where the lading has settled as much as 1.5 inches, which is very unusal. It is preferred that the tension be at least 1,000 pounds after settlement. Most preferably the tension should be at least 1,500 pounds after settlement of 1 inch.

It is further preferred that the lading not travel more than about 24 inches longitudinally before resilient deflection of the resilient means substantially ceases. For example, in the case of a metal spring the spring would go solid at this point. Alternatively, for a metal spring or a resilient means comprising rubber in shear, stops may be provided to limit travel of the resilient means. It is most preferred that resilient deflection substantially cease after longitudinal lading travel of not more than about 12 inches.

While load L has been illustrated as packaged lumber, it is to be understood that this banding arrangement may be employed on other loads, and is particularly adapted for loads having a generally rectangular cross section. Further, while the resilient means has been illustrated as compression spring assemblies 28, other resilient means may be employed satisfactorily, such as rubber in shear. However, the deflection of other resilient means would be roughly the same as the spring assemblies 28 and would pretension the banding about the same amount as spring assemblies 28.

When it is desired to remove the load from flat car 10, it may be hazardous to cut or snip the banding while the banding is under a substantial tensioning, such as 3,000 pounds of tension, since the cut ends may whip or flail about. Thus, it is desirable to remove at least a portion of the tensioning in the steel banding. One arrangement for releasing the tensioning is shown in FIG. 8 in which a loop 60 has its end portions 62 secured by crimped connectors or splicer 64 to the banding 50A which has its ends secured by connectors 52A. Loop 60 bypasses the connected ends of banding A. To release the tensioning in banding 50A, a worker cuts band 50A at a position between the connectors 64 which snaps loop to a taunt relation and releases the tensioning in banding 50A. With the tensioning released, banding 50A may then be cut at another position to release the banding from about the lumber.

FIG. 8A illustrates another manner of forming the banding loop. An extending end portion 60A of banding 50A is looped over banding 50A and a crimped connector 64A secures the end portion 60A to banding 50A. In this position banding 50A may be cut between

connectors

64 and 64A to release the pretensioning.

Referring to FIGS. 9-11, a separate arrangement for releasing the tensioning in the banding is illustrated. A clevis 66 on the lower end of chain 40A is pivotally connected at 68 to the upper end of a movable rod 70 and a flexible seal 72 is secured adjacent the lower end of rod 70. An angle 74 is secured between leg 20A of side sill angle 18A and vertical web 24A. Secured to the underside of angle74 is a hollow cylinder 76 in which seal 72 is mounted for movement. Rod 70 extends through an opening 78 in the lower horizontal leg of angle 74 which opening is larger in diameter than rod 70 therefore permitting a release of air from cylinder 76 upon an upward movement of seal 72. Rod 70 has a reduced diameter portion 80 and lock lever 82 is pivotally mounted at 84 to angle 74. Lever 82 has an end hook portion 86 adapted to fit about the reduced diameter portion 80 of rod 70. A retainer 88 is mounted over the end of hook portion 86 and pins 90, which secure retainer 88, form stops for the end of hook portion 86. Lever 82 may be releasably secured in a locked position by pin 92 in bracket 94. In the position shown in FIG. 9, with rod 70 having its lower end seated on lower flange 26A and lever 82 engaged with reduced diameter 80, the banding is placed about the load and pretensioned as set forth above. When it is desired to release the pretensioning from the banding for removal of the banding, pin 92 is removed from bracket 94 and lever 82 is pivoted about pivot 84 to remove hook portion 86 from reduced diameter portion 80 of rod 70. Longitudinal rod 70 then moves upwardly in a relatively slow manner as seal 72 forces air from cylinder 76 through opening 78 thereby minimizing any snapping action in the banding when the tensioning is released.

Referring to FIGS. 12 and 13, a further embodiment for releasing the tensioning is illustrated in which a yoke 96 is pivotally mounted to the upper end of yoke 32A about pivot 98. An overcenter link 100 is pivoted about pivot 102 to yoke 96 and has an axis 103 about which banding 50B is mounted. Link 100 thus may be rotated or moved in an are A between an overcenter secured position shown in solid lines in FIGS. 12 and 13 and an unlocked position shown in broken lines in FIG. 12. A retaining pin 104 holds link 100 in the overcenter position. To release the tensioning, pin 104 is removed and a pry bar or the like is placed in the opening of yoke 96 beneath axis 103 and link 100 is urged outwardly past a dead center relation with respect to axis 102 thereby effecting movement of link 100 to the broken line position shown in FIG. 12 and a release of tensioning from banding 50B.

In accordance with another embodiment of the present invention as shown in FIGS. 14-l6, tie-down assembly 128, comprises a resilient means 130 for providing tension to the strapping, means 140 for providing rotational movement of the tie-down assembly about a generally vertical axis, and a means 141 for receiving the lading strapping. Resilient means 130 comprises spring 131 having tensioning properties as described above and having

followers

136 and 138.

Yoke 132 has mounted therein an assembly generally designated 140 for permitting rotation of the tie-down assembly about its generally vertical axis during tensioning of the strapping. Assembly 140 preferably comprises one or

more links

147, 148 having means interconnecting them 149 to provide a wide degree of rotation movement about the axis of the hold down assembly. One example of an appropriate means for providing rotational movement is a swivel. The means for providing rotational movement are preferably but not necessarily connected directly respectively to the means for receiving the lading strapping 141 and resilient means 130.

The rotational freedom of movement reduces the stress concentration on the straps passing through the assembly because the separation of the straps as shown at 54 in FIG. 1 tends to cause the assembly to rotate during tensioning. Restraint of this rotation creates stress concentrations in the straps which can nucleate cracks and eventually lead to failure of the strapping.

lnterconnecting with assembly 140 for providing rotation is a lading strap receiving assembly 141. This assembly comprises link means for receiving lading strapping 151 in this embodiment comprising a chain clevis 142. A rotatable pin 144 may be provided in the clevis and strapping 151 may ride around rotatable pin 144. In accordance with another embodiment a collar 143 is provided on clevis 142 for receiving the strapping. Means are preferably provided on the collar to avoid the strapping bearing against the upward extension of legs of the clevis, for example, by providing the collar 143 with a diameter substantially equal to or in excess of the diameter of clevis 143 as shown in FIG. 17. If the strapping bears against the clevis legs, stress concentra' tions are introduced into the banding which can nucleate cracks which eventually cause failure of the bandmg.

It is not necessary that the means for allowing rotational movement 140 be located between the resilient means 130 and strapping receiving means 141. The means allowing rotational movement may be located below the resilient means, as shown, for example, in FIGS. 2 and 3.

As is also shown in FIGS. 14-17, tie-down assembly 128 is mounted within hold-down assembly 160 by means of pin 161 extending between and within

plates

163, 165 which are mounted on the car floor or on an appropriate support 166 on the side of the car such as a bracket 167. A horizontal portion 168 of bracket 167 is extended to provide support for spring assembly 128. Thus when strapping 151 is removed therefrom, the assembly pivots about pin 161 and falls automatically by gravity into the storing position shown in FIGS. 14 and 1S.

Plates

163, 165 guide the pivotal movement and the car floor or horizontal extension 168 supports assembly 128 in storage or in transit until it is again utilized.

Another feature of the present tie-down assembly is that it be mounted for pivotal movement to accommodate movement of the lading as shown, for example, in FIGS. 2 and 3. In this embodiment chain 40 is free to pivot about link 42. In the embodiment shown in FIGS. 14-16, clearance is provided between

plates

163, 165 and resilient means 130 (i.e., yoke 134 in FIG. 16) to allow such movement. Furthermore, there must be sufficient clearance to allow assembly 128 to pivot laterally inwardly toward the car to the extent of at least about 5 to accommodate varying load heights.

In accordance with another embodiment, a tie-down assembly 228 similar to the one shown in FIGS. 14-17 is shown in FIGS. 18-21 and includes a spring assembly 230 including a compression spring 231 mounted around a pair of

yokes

232 and 234. A follower 236 on the end of yoke 234 and a follower 238 on the end of yoke 232 engage opposite ends of spring 231 for compressing the same. A swivel means 246 is provided between spring assembly 230 and lading receiving means 240.

In this embodiment the lading receiving means 240 comprises a single piece link 241. As shown in FIG. 21, the end portions 241a, 241b, and 2410 are contoured to angles of approximately or less and rounded corners are avoided. This substantially avoids introducing stress concentration into the banding which would occur if rounded corners are used where the banding can partially move around the corner. Also, since the link is made in one piece there are no arms which bear against the strapping and introduce stress concentrations.

As is also shown in FIGS. 18-20, tie-down assembly 228 is pivoted at its opposite end about a hold-down assembly indicated generally at 260. The assembly 260 comprises

plates

263 and 265 in which pin 261 is generally mounted therebetween. Clearance as described in connection with FIGS. 14-17, is provided between the plates for pivotal movement of assembly 228 longitudinally and laterally.

After the banding 250 is removed from spring assembly 228, the spring assembly may be dropped and

plates

265 and 263 will guide the spring assembly to a storing position on the car floor or on the side of the car as shown in FIGS. 19 and 20. Means 270 are provided to support the spring assembly adjacent the side of the car. For example, a suitable bracket 271 may be utilized having a horizontal extension 272 which engages the spring assembly in the stored position. In the stored position plate 263 also prevents spring assembly 228 from rotating downwardly in the stored position. Plate 263 is preferably made longer longitudinally than it extends in a vertical direction to aid its guiding function, and prevent the spring unit from swinging out excessively.

What is claimed is:

1. A tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car comprising:

a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading straps with said seat;

a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches;

means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20;

and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse t the side of the car,

said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches.

2. An assembly according to claim 1 wherein the means allowing rotational movement is a swivel.

3. An assembly according to claim 1 wherein the means for allowing rotational movement comprises a chain.

4. An assembly according to claim 1 wherein said resilient assembly is capable of retaining at least about 1,000 pounds after load settlement of one inch.

5. An assembly according to claim 1 wherein said lading strap receiving assembly comprises a clevis.

6. A tie-down assembly according to claim 5 wherein the swivel means is capable of unlimited rotational movement about its own generally vertical axis.

7. A tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping comprising:

a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading strapping with said seat;

lading strapping passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said lading strap receiving assembly;

a resilient assembly comprising means compressible to at least 3,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches;

a chain allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping;

and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car; said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 12 inches.

8. A tie-down assembly according to claim 7 wherein said lading strapping includes means to reduce the tensioning of the strapping prior to removal thereof from the banding.

9. A tie-down assembly according to claim 8 wherein the means to reduce tensioning of the strapping includes at least one loop adopted to be severed to release the tension.

10. A tie-down assembly according to claim 8 wherein the means to reduce the tensioning of the strapping comprises a fluid cylinder operatively connected to said strapping adjacent each side of the car and having a movable seal therein, and releasable securing means connected to said seal to hold said seal in one position during pretensioning of the strapping, said securing means upon release etTecting actuation of said seal within said cylinder and a relatively gradual movement of the seal to provide a gradual release of tensioning in the strapping.

11. A tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car comprising:

said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches;

a swivel means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20;

and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, and allowing limited pivotal movement about an axis parallel to the side of the car to provide automatic movement of said tiedown assembly to a stored position extending generally longitudinally of the car upon release of said straps.

12. An assembly according to claim 11 wherein the means allowing pivotal movement include spaced plates with a pin mounted therebetween which engages a portion of the tie-down assembly.

13. An assembly according to claim 12 wherein clearance is provided between the portion of the tiedown assembly mounted therein and said plates.

14. In a tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car the improvement comprising:

a lading strap receiving assembly including a curved seat and side restraining means maintaining engagement of said lading straps with said seat;

a swivel means allowing a wide degree of rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping in excess of at least about 20;

and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches.

15. An assembly according to claim 14 wherein the lading strap receiving assembly comprises a clevis.

16. An assembly according to claim 15 wherein said clevis is provided with a rotatable member engaging the strapping.

17. An assembly according to claim 16 wherein the clevis is provided with a collar mounted on said rotatable member.

18. An assembly according to claim 17 wherein said collar has a diameter equal to or greater than the diameter of the clevis legs.

19. An assembly according to claim 14 wherein the lading strap receiving assembly comprises a link having corners on the inside of the links without rounded edges for reducing stress concentrations in the strapping passing therethrough.

20. An assembly according to claim 14 wherein said resilient assembly is capable of retaining at least about 1,000 pounds of tension after settlement of the lading.

21. An assembly according to claim 20 wherein the resilient assembly is capable of returning at least 1,500 pounds of tension after lading settlement of one inch.

22. A tie-down assembly according to claim 14 wherein the swivel means is capable of unlimited rotational movement about its own generally vertical axis.

23. in a tie-down assembly to be mounted upon pposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car the improvement comprising:

a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 'l .5 inches;

24. A railway flat car comprising:

a plurality of tie-down assemblies mounted upon opposite sides along the longitudinal length of the car generally at the car deck level to secure a lading to the car deck;

expendable lading strapping having straps passing over the lading in a double-loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car;

swivel means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20;

and means allowing longitudinal pivotal movement of said tie down assembly about an axis transverse to the side of the car, said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches.

25. A railway flat car comprising:

expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car;

and mounting means mounting said tie-down assemblies on the car and allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, and allowing limited pivotal movement about an axis parallel to the 27. A railway flat car as set forth in claim 26 wherein at least one of said plates has a greater horizontal extent than vertical extent.

28. A railway flat car as set forth in claim 27 wherein the outermost plate has a greater horizontal extent than vertical extent.

Claims

1. A tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car comprising: a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading straps with said seat; a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches; means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20*; and means allowing longitudinal pivotal movement of said tiedown assembly about an axis transverse to the side of the car, said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches.

7. A tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping comprising: a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading strapping with said seat; lading strapping passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said lading strap receiving assembly; a resilient assembly comprising means compressible to at least 3,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches; a chain allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping; and means allowing longitudinal pivotal movement of said tie-down assembly about aN axis transverse to the side of the car; said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 12 inches.

10. A tie-down assembly according to claim 8 wherein the means to reduce the tensioning of the strapping comprises a fluid cylinder operatively connected to said strapping adjacent each side of the car and having a movable seal therein, and releasable securing means connected to said seal to hold said seal in one position during pretensioning of the strapping, said securing means upon release effecting actuation of said seal within said cylinder and a relatively gradual movement of the seal to provide a gradual release of tensioning in the strapping.

11. A tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car comprising: a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading straps with said seat; a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches; said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches; a swivel means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20*; and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, and allowing limited pivotal movement about an axis parallel to the side of the car to provide automatic movement of said tie-down assembly to a stored position extending generally longitudinally of the car upon release of said straps.

13. An assembly according to claim 12 wherein clearance is provided between the portion of the tie-down assembly mounted therein and said plates.

14. In a tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car the improvement comprising: a lading strap receiving assembly including a curved seat and side restraining means maintaining engagement of said lading straps with said seat; a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches; a swivel means allowing a wide degree of rotational movement of said lading strap receiving assembly about its own generally verTical axis during tensioning of the strapping in excess of at least about 20*; and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches.

23. In a tie-down assembly to be mounted upon opposite sides along the longitudinal length of a railway flat car generally at the car deck level to secure a lading to the car deck with expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car the improvement comprising: a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading straps with said seat; a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches; said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches; a swivel means allowing a wide degree of rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping in excess of at least about 20*; and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, and allowing limited pivotal movement about an axis parallel to the side of the car to provide automatic movement of said tie-down assembly to a stored position extending generally longitudinally of the car upon release of said straps.

24. A railway flat car comprising: a plurality of tie-down assemblies mounted upon opposite sides along the longitudinal length of the car generally at the car deck level to secure a lading to the car deck; expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car; a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading straps with said seat; a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tEnsion after settlement of the lading of up to 1.5 inches; swivel means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20*; and means allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches.

25. A railway flat car comprising: A plurality of tie-down assemblies mounted upon opposite sides along the longitudinal length of the car generally at the car deck level to secure a lading to the car deck; expendable lading strapping having straps passing over the lading in a double loop with said straps being spaced at upper side corners of the lading and engaging said tie-down assemblies along the length of the car; a lading strap receiving assembly comprising means including a curved seat and side restraining means maintaining engagement of said lading straps with said seat; a resilient assembly comprising means compressible to at least 2,000 pounds to provide restraint of said lading mounted upon the car and capable of retaining at least 750 pounds of tension after settlement of the lading of up to 1.5 inches; said resilient assembly being characterized by deflection of the resilient assembly substantially ceasing after longitudinal lading travel of not more than about 24 inches; a swivel means allowing rotational movement of said lading strap receiving assembly about its own generally vertical axis during tensioning of the strapping to the extent of at least about 20*; and mounting means mounting said tie-down assemblies on the car and allowing longitudinal pivotal movement of said tie-down assembly about an axis transverse to the side of the car, and allowing limited pivotal movement about an axis parallel to the side of the car to provide automatic movement of said tie-down assembly to a stored position extending generally longitudinally of the car upon release of said straps.

26. A railway flat car as set forth in claim 25 wherein said mounting means comprise two spaced apart plates with a pin therebetween mounted on the car side.

27. A railway flat car as set forth in claim 26 wherein at least one of said plates has a greater horizontal extent than vertical extent.