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Publication numberUS3836186 A
Publication typeGrant
Publication dateSep 17, 1974
Filing dateMay 10, 1973
Priority dateMay 10, 1973
Publication numberUS 3836186 A, US 3836186A, US-A-3836186, US3836186 A, US3836186A
InventorsH Kennedy
Original AssigneeH Kennedy
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lock mechanism for freight car doors
US 3836186 A
A lock mechanism including a plate of substantial mass for locking engagement with door mounted followers. The plate mass requiring lifting by means other than manual effort to prevent unauthorized entry into the car. Limited vertical travel of the plate engages inclined plate surfaces with the door mounted followers to impart initial opening movement to the door. Plate travel in an opposite direction imparts final closing movement to the door. The plate is adapted to receive lifting instrumentalities such as a lift truck fork for door opening purposes.
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Description  (OCR text may contain errors)

United States Patent 1 Kennedy Sept. 17, 1974 LOCK MECHANISM FOR FREIGHT CAR DOORS [76] Inventor: Harvey J. Kennedy, 127 Bauer Ln.,

Eugene, Oreg. 97402 [22] Filed: May 10, 1973 [21] App]. No.: 358,875

[52] US. Cl. 292/189, 292/D1G. 32

[51] Int. Cl. E05c l/04, E05b 65/14 [58] Field of Search 292/25, 96, 101, 116, 117, 292/120, 130, 131, 136, 138, 145, 156, 157,

162, 164, 175, 183, 184, 189, 302, DIG. 32,

DIG. 68; 70/70, 71, 72, 393, 407

[56] References Cited UNITED STATES PATENTS 232,448 9/1880 Bradley 292/25 787,038 4/1905 Hahn 292/58 1,178,774 4/1916 Albright 70/134 1,258,826 3/1918 Thompson 292/162 1,602,865 10/1926 Stockov 70/72 1,715,558 6/1929 Long 70/72 2,568,592 9/1951 OConnor 292/87 3,403,432 [0/1968 Bencene 27/17 3,751,949 8/1973 Castle 70/144 Primary Examiner-Albert G. Craig, Jr. Attorney, Agent, or FirmJames D. Givnan, Jr.

[5 7 ABSTRACT A lock mechanism including a plate of substantial mass for locking engagement with door mounted followers. The plate mass requiring lifting by means other than manual effort to prevent unauthorized entry into the car. Limited vertical travel of the plate engages inclined plate surfaces with the door mounted followers to impart initial opening movement to the door. Plate travel in an opposite direction imparts final closing movement to the door. The plate is adapted to receive lifting instrumentalities such as a lift truck fork for door opening purposes.

2 Claims, 7 Drawing Figures LOCK MECHANISM FOR FREIGHT CAR DOORS BACKGROUND OF THE INVENTION The present invention concerns a locking mechanism for railway car doors.

For some period of time a steady increase has occurred in the number of unauthorized entries into freight cars by thieves or vandals. To a large extent conventional door locking mechanisms on railway cars do not provide adequate security but rather rely upon the deterent effect of a seal, the breaking of which constitutes a Federal crime. For one reason or another such a deterent is no longer adequate.

The value of goods transported within railroad merchandise cars and the ready disposal of same through illegal channels results in such cars being subject to frequent theft. The resulting lose of merchandise results in higher insurance rates which ultimately, for the most part, are passed on to the consumer.

Another problem encountered by existing freight car door structures is the problem of initiating car door movement from a locked position. The car door is of considerable mass with the metal bearing surfaces supporting same being subjected to the weather all of which requires considerable force to overcome during the initial stages of door opening.

SUMMARY OF THE INVENTION The present locking mechanism includes an elongate plate of substantial mass which locks and unlocks the car door by movement along a vertical path. Lifting equipment such as a lift truck or hydraulic equipment is required for such movement of the plate. Such equipment is of a cost and size so as to be not readily available to a thief or vandal.

The plate defines inclined surfaces which during vertical plate movement function as cam surfaces to impart initial opening and conversely final closing movement to the door. Said locking plate additionally defines a recessed area within which a lift fork end or a jack component may be inserted for plate lifting. The plate is retained for limited vertical movement adjacent a sidewall of the car by keeper means on the car sidewall.

An important object of the present invention is to provide a lock for railway car doors which requires special equipment for opening and which equipment is normally available on a loading dock but not readily available to or conveniently transported by a wrongdoer. Accordingly, the present lock lends itself to convenient opening by authorized people operating equipment normally found on elevated loading docks while oppositely being inoperable without such equipment. Accordingly, unauthorized entry to a car parked on a siding would be extremely difficult.

A further object is to provide a door lock for railway cars which lock includes means for imparting opening movement to a car door. Oppositely, in a locking operation the weight of the locking plate urges the car door to its locked or seated position.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. I is a side elevational view of a portion of a freight car sidewall with the present lock mechanism in place thereon,

FIG. 2 is a view similar to FIG. 1 with the freight car door moved to a closed and locked position,

FIG. 3 is a horizontal section taken along line 33 of FIG. 2 disclosing details of the present lock mechal'llSm,

FIG. 4 is an elevational view taken along line 4-4 of FIG. 1 showing details of follower construction in place on the locking edge of the door,

FIG. 5 is a vertical section taken along line 55 of FIG. 2 showing a locking plate recess for lift fork engagement.

FIG. 6 is a view similar to FIG. 5 showing a modified recess, and

FIG. 7 is a view similar to FIGS. 5 and 6 disclosing a locking plate attachment for engagement with the end of a lift fork or other source of lifting force.

DESCRIPTION OF PREFERRED EMBODIMENTS With continuing reference to the accompanying drawings wherein applied reference numerals indicate parts similarly identified in the following specification, the reference numeral 1 indicates the sidewall of a railroad freight car with a roof structure at 2 all of conventional construction. The sidewall structure 1 defines generally an open area 3 through which cargo passes during loading and unloading operations. Supported by the car sidewall adjacent area 3 is a door framework 4 slidably supporting a car door 6 entrained for rectilinear movement within the framework 4. Friction reducing means such as rollers as at 7 may be utilized intermediate the door and its supporting framework facilitating opening and closing movement.

Located adjacent one side of door framework 4 is a locking plate 8 of substantial mass orientated in parallel relationship to an upright door frame member indicated at 4A. Locking plate 8, in one embodiment, is of steel having a thickness of approximately one inch and weighing approximately 650 to 800 pounds depending on its specific dimensions. In juxtaposition with locking plate 8 is a spacer member 9 having a friction reducing surface 9A constituting a bearing surface against which the locking plate may slide during movement of the latter. Retainer means or keepers at 10 for the locing plate terminate at their inner ends in suitable securement with the car sidewall structure and extending outwardly therefrom each terminating in a head 11 which confines the locking plate 8 into juxtaposition with spacer member 9. Elongate, upright openings 8A in the plate, cooperate in a sliding manner with retainer means 10 with said locking plate thereby adapted for limited vertical travel and normally resting in its lowermost position indicated in FIG. 1.

An upright edge 88 of locking plate 8 is provided with inset areas 12 defined by upper and lower inclined plate surfaces 13 and 14 which coact with door mounted follower means described below.

Mounted on said door and extending outwardly therefrom are a pair of door members 15 extending the height of the door and which in conjunction with the leading edge of 6A of the door form a channel-like structure as viewed in FIG. 3 for reception of locking plate edge 88. Said edge may be weatherstripped as at 19.

Follower assemblies at 16 are mounted intermediate door carried plate members 15 and as shown in FIG. 4 preferably incorporate friction reducing means such as roller bearings 22. The outer annular member of each follower 16 is of a diameter permitting at least half of the followers entry somewhat past the upright edge 88 of locking plate 8 and at least partially into an inset area 12. Such entry may occur only when the locking plate 8 is in an elevated position. In closing and locking door 6 the followers 16 need only be placed in a posi tion whereat the upper inclined surfaces 13 of the plate may act thereon during downward plate movement. Such movement results in said surfaces acting on the followers and hence door 6 to move same to a locked position as viewed in FIG. 2.

Within locking plate 8 is formed a recess 17 of adequate size to receive the end segment of a lift fork, the fork being indicated at F. As such forks are adjustably mounted for positioning toward and away from one another, recess 17 may be of a horizontal dimension adequate to receive both fork tips when the latter are positioned inwardly adjacent one another. Further, conventional fork truck structure also permits use of a single fork with the remaining fork being retracted into an unused position whereat it would not hinder use of the single plate engaging fork.

As viewed in FIG. 5, plate recess 17 may extend through plate 8 with lifting of the fork imparting unlocking movement to the plate. During such movement the end of the fork tip may slide upwardly along the surface 9A of spacer 9 with the inner surface of plate 8 moving in sliding, surfacial contact with surface 9A. During such movement of plate 8 the lower pair of inclined plate surfaces 14 act on followers 16 to impart initial door opening movement to same in the direction indicated by the applied arrows as viewed in FIG. 2.

The plate recess 17 may be defined by internal plate surfaces including a surface other than in the normal relationship to the plate side surfaces as per the recess 17 shown in FIG. 6. The plate recess shown in FIG. has an inclined wall 18 to prevent any lifting by a medium not having adequate resistance to a horizontal component of force resulting from the inclined wall surface 18.

A still another arrangment may be provided wherein locking plate 8 requires the mounting of an appendage at 20 prior to engagement with a fork tip or other lifting instrumentality. The appendage 20 would be applied to the door by detachable fasteners 21 which only authorized personnel on a loading dock would have ready access to.

Importantly, recess 17 is a substantial distance above the railroad bed or siding right-of-way making same beyond the reach of an unaided person.

For unlocking of the car door when loading or unloading is to be performed at other than a loading dock, lifting of plate 8 may be by a hydraulic jack mounted on a truck bed with the working end of the moving lift component being fitted with a counterpart to the lift truck fork. The force required to raise plate 8 to its upper limit of travel to discharge followers 16 from inset areas 12 will be somewhat greater than the weight of plate 8 by reason of the added force required to displace door 6 through its initial opening movement. While such a force is easily within the capabilities of a lift truck or with a hydraulic jack in close coupled engagement with plate 8, an individual working from ground level at a considerable distance from plate recess 17 would find imparting such a force extremely difficult and requiring considerable equipment.

While not limited to freight cars of the merchandise class such class of cars may be readily converted to incorporate the present lock mechanism without extensive modification and attendant costs.

While I have shown but a few embodiments of the invention, it will be apparent to those skilled in the art that the invention may be embodied still otherwise without departing from the spirit and scope of the invention.

Having thus described the invention what I desire to secure under a Letters Patent is:

l. A door lock mechanism for railroad freight cars, said lock mechanism comprising,

a locking plate vertically disposed along the side wall of a freight car and adapted for limited vertical travel between a raised door unlocking position and a lowered door locking position, said plate of a weight requiring a mechanized lifting instrumentality such as a lift truck, said plate defining a transversely orientated recess for temporary inserted engagement with the lifting instrumentality enabling unlocking motion to be imparted to said plate,

a framework mounted on the freight car side wall and concealing the lower edge of said plate to prevent the application of a lifting force to said edge by unauthorized parties,

means mounting said plate to the freight car side wall permitting limited vertical movement of the plate along its major axis, and

said plate further defining at least one inset area formed along a vertical edge of the plate for reception of a door mounted follower. said inset area in the plate defined by a lower upwardly inclined plate surface which coacts with said follower in a cam-like manner to impart initial horizontal opening movement to a freight car door upon upward travel of said plate and an upper inclined plate surface which coacts conversely with said follower imparting final horizontal closing movement to said door coincident with gravitational movement of the plate.

2. The door lock mechanism as claimed in claim I wherein the transversely orientated recess is partially defined by plate surfaces other than normal to the plate exterior surface.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US232448 *Jun 22, 1880Sep 21, 1880 Lock for car-doors
US787038 *Dec 14, 1904Apr 11, 1905John J HahnDoor-fastening device for grain-doors.
US1178774 *Jun 28, 1915Apr 11, 1916Roy R AlbrightLock.
US1258826 *Mar 22, 1917Mar 12, 1918Thomas J ThompsonStorm-window fastener.
US1602865 *Sep 25, 1925Oct 12, 1926Perkiomen Trunk And Bag CompanLocking means for wardrobe trunks
US1715558 *Aug 2, 1928Jun 4, 1929 X t trunk lock
US2568592 *May 31, 1946Sep 18, 1951Lyon Metal Products IncHandle for locker latches
US3403432 *Mar 7, 1966Oct 1, 1968Weber Knapp CoLatching mechanism for a burial casket or the like
US3751949 *Oct 1, 1971Aug 14, 1973Castle ALocking device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5686899 *Feb 2, 1995Nov 11, 1997Hosmer; William F.Truck van door lock
US6739093Nov 8, 2002May 25, 2004Charles S. HolbertFarm gate stop device
US6854775 *Feb 11, 2003Feb 15, 2005Miner Enterprises, Inc.Bar lock assembly
US20040155471 *Feb 11, 2003Aug 12, 2004Senn Brian A.Bar lock assembly
US20110025145 *Mar 20, 2009Feb 3, 2011Siemens AktiengesellschaftMagnet apparatus of an electrical machine with a coolant line
U.S. Classification292/189, 292/DIG.320
International ClassificationE05B65/16, E05C19/00
Cooperative ClassificationE05B83/12, Y10S292/32, E05C19/001
European ClassificationE05B83/12, E05C19/00B