| United States Patent | 3,696,240 |
| Potter | October 3, 1972 |
LIGHT FIXTURE FOR A LOADING DOCK
Abstract
A light fixture for a loading dock. The light fixture includes an inner arm which is mounted for pivotal movement with respect to a fixed support, and an outer arm is pivotally connected to the outer end of the inner arm by a tubular coupling. A shell in which a light bulb is mounted is connected to the outer arm by a tension spring which provides shock absorbing characteristics for the shell. The arms are arranged to pivot in a common plane from an extended position in which the outer arm is located in axial alignment with the inner arm to a retracted or folded position in which the outer arm is located parallel to the inner arm. An electrical cord extends through the hollow inner arm, through a passage in the coupling, through the hollow outer arm and spring and is connected to the bulb in the shell.
| Inventors: | Potter; Roderick B. (Milwaukee, WI) |
| Assignee: |
Kelley Company, Inc.
(Milwaukee,
WI)
|
| Appl. No.: | 05/057,511 |
| Filed: | July 23, 1970 |
| Current U.S. Class: | 362/418 |
| Current International Class: | F21V 15/00 (20060101); F21V 15/04 (20060101); F21V 21/14 (20060101); F21V 21/26 (20060101); F21V 21/28 (20060101); F21s 001/02 () |
| Field of Search: | 240/73BJ,90 287/92 267/178 |
| 2458967 | January 1949 | Wiedenhoeft |
| 3287549 | November 1966 | Lantery |
| 2925294 | February 1960 | Schwartz |
| 1848514 | March 1932 | Cunningham |
| 629185 | July 1899 | Arnold |
I claim:
1. A light fixture for use on a loading dock, comprising a first tubular arm, a second tubular arm, a coupling pivotally connecting the first arm and the second arm, said second arm being mounted for movement between a first folded position in which the second arm is disposed substantially parallel to the first arm and located on one side of the first arm to an extended position in which the first and second arms are in axial alignment to a second folded position in which the second arm is disposed substantially parallel to the first arm and located on the opposite side of said first arm, said coupling having a generally straight passage therethrough communicating with the interior of both of said first arm and said second arm, said passage being disposed in axial alignment with the interior of both the first and second arms when the second arm is in the extended position, illuminating means connected to the outer arm, and an electrical cord extending through the interior of the first arm, through said passage and through the interior of said second arm and being connected to said illuminating means, the surfaces of the coupling bordering the ends of the passage being generally curved to permit the cord to bend smoothly over the surfaces when said arms are moved between the extended and folded positions.
2. The light fixture of claim 1, wherein said illuminating means includes a shell connected to said second arm, and a light bulb mounted within the shell.
3. The light fixture of claim 1, and including a tension spring connecting said second arm and said illuminating means, said tension spring including a series of turns with adjacent turns being in substantially contiguous relation.
4. A light fixture for use on a loading dock, comprising mounting means to be connected to a fixed support, a generally horizontal first tubular arm, pivotal means for pivotally connecting the inner end of said first arm to said mounting means, a generally horizontal second tubular arm, coupling means pivotally connecting the outer end of said first arm to the inner end of said second arm, said coupling means including a pair of first connecting members connected to the outer end of the first arm and projecting beyond said outer end at diametrically opposite locations and a pair of second connecting members connected to the inner end of said second arm and projecting beyond said inner end at diametrically opposite locations, said coupling means also including a tube having a central passage disposed in communication with the interior of both said first and second arms, the projecting portions of said first connecting members being pivotally connected to one end of said tube and the projecting portions of said second connecting members being pivotally connected to the opposite end of said tube, said second arm being mounted for movement between a first position in which the second arm is disposed substantially parallel to the first arm and located on one side of the first arm to a second position in which the second arm is disposed substantially parallel to the first arm and located on the opposite side of said first arm, illuminating means connected to the second arm, and an electrical cord connected to a source of electrical energy and extending through the interior of said first arm through the passage in said tube and through the interior of said second arm and being connected to said illuminating means.
5. The light fixture of claim 4, wherein surfaces of the tube bordering the ends of said passage are generally curved to permit the cord to bend smoothly over the surfaces when said arms are moved between the extended and folded positions.
6. The light fixture of claim 4, wherein said pivotal means includes a hollow sleeve mounted for pivotal movement with respect to said mounting means and secured to said first arm, said electrical cord extending within the hollow interior of said sleeve.
7. The light fixture of claim 6, wherein said sleeve is mounted to pivot about a vertical axis and said arms are mounted to pivot in the same horizontal plane.
8. The light fixture of claim 4, and including a preloaded tension spring connecting the outer end of said second arm and said illuminating means, said tension spring including a series of turns with adjacent turns being in substantially contiguous relation.
This invention relates to a light fixture, and more particularly to a light fixture to be used on a loading dock.
A loading light is normally installed on a loading dock to facilitate loading and unloading of railway cars, semi-trailers, and the like. Even during daylight hours, the interior of a railway car or semi-trailer is relatively dark so it is desirable to utilize a light to illuminate the interior. The conventional loading light is adjustable so that the beam can be directed toward the area being loaded or unloaded and in addition, the loading light must be mounted in a manner so that it will not interfere with the operation of a forklift truck or other unloading equipment, nor will it interfere with the normal use of the dock when the loading light is not in use.
The present invention is directed to an improved adjustable light fixture for a loading dock, More specifically, the light fixtures includes an inner arm having one end pivotally connected to a fixed support on the dock, and an outer arm is pivotally connected to the outer end of the inner arm by a tubular coupling. The outer arm is arranged to pivot from an extended position, in which the outer arm is located in axial alignment with the inner arm, to a retracted or folded position in which the outer arm is located parallel to the inner arm. Connecting the outer arm to a shell, which houses a light bulb, is a tension spring that provides shock absorbing characteristics for the shell.
The electrical connection to the bulb is provided by a cord which extends through the hollow interior of the inner arm, passes through an axial passage in the coupling and extends through the hollow outer arm and spring to the shell.
The light fixture of the invention is fully adjustable from the extended position, in which the outer arm is located axially with respect to the inner arm, to the folded or retracted position in which both arms are parallel and can be located along the wall or other supporting structure.
As the electrical cord extends completely through the arms as well as through the coupling, a more attractive unit is provided which minimizes the mount of exposed electrical cord. In addition, the construction acts to shield the cord so that it will not be accidentally contacted by a forklift truck, or other object.
As a further advantage, the arms can be pivoted with respect to each other without interference from the cord, and there is no possibility of the cord being crimped or severed between the arms during the pivotal movement as can occur in conventional light fixtures.
The use of the preloaded tension spring for connecting the outer arm to the shell, which houses the light bulb, provides improved shock absorbing characteristics for the unit and enables the light fixture to withstand a substantial impact without danger of breaking of the light bulb.
Other object and advantages will appear in the course of the following description.
The drawings illustrate the best mode presently contemplated of carrying out the invention.
In the drawings:
FIG. 1 is a side elevation of the light fixture of the invention as mounted on a loading dock;
FIG. 2 is a plan view of the light fixture of FIG. 1 in the folded or retracted position;
FIG. 3 is an enlarged vertical section showing the mounting structure for connecting the inner arm to the dock;
FIG. 4 is an enlarged plan view with parts broken away showing the details of the coupling with the arms being in the extended position; and
FIG. 5 is an enlarged plan view of the coupling with parts broken away and showing the arms in the folded position.
The drawings illustrate a light fixture 1 to be mounted on a fixed support 2, such as a wall of a building bordering a loading dock, a post or a fixed standard. As shown in FIGS. 1 and 2, the light fixture 1 includes a mounting bracket 3 which is connected to the wall or other supporting structure 2 and a pair of lugs 4 extend outwardly from the mounting bracket 3 in vertically spaced relation. As best shown in FIG. 3, a tube 5, having a generally square cross section, is located between the lugs 4 and suitable washers 6 are positioned between the respective ends of the tube 5 and the corresponding surfaces of the lugs 4.
A cylindrical sleeve 7 is mounted within each open end of the tube 5 and is secured within the tube by a plug weld 8. The outer end of each sleeve 7 projects beyond the corresponding end of tube 5 and is journaled within an opening in the respective lug 4 by a bearing 9 so that the sleeves 7, as well as the tube 5, will rotate with respect to the mounting bracket 3 and lugs 4. The washers 6 serve as thrust bearings for the rotational movement.
One end of a tubular inner arm 10 is welded to the outer surface of tube 5 and a pair of gusset plates 11 are secured between the arm 10 and tube 5 for added reinforcement. The outer end of arm 10 is secured to the inner end of tubular outer arm 12 by a coupling 13 which permits pivotal movement between the arms 10 and 12.
To provide the connection between arms 10 and 12, a pair of saddles 14 are secured to the outer end of arm 10 and are provided with a generally U-shaped cross section with a contour to complement the circular contour of the arm 10. A weld joins the longitudinal side edges of the saddles 14 together, as well as securing the saddles 14 to the tube 10.
A generally flat extension 15 extends outwardly from each of the saddles 14 and button head screws 16 extend through openings in the respective extensions 15 and are threaded within openings in a hinge tube 17 of coupling 13. Suitable washers 18 are located on either side of the extension 15. This connection permits the hinge tube 17 to pivot with respect to the inner arm 10.
A second pair of saddles 19, similar to saddles 14, are secured to the inner end of arm 12. The saddles 19 are generally U-shaped in cross section and a weld joins the longitudinal side edges of the saddles 19 together as well as securing the saddles to the end of the outer arm 12. Extensions 20, similar to extensions 15 extend outwardly from saddles 19 and screws 21 extend through openings in the extensions 20 and are threaded within openings in the hinge tube 17. Washers 22 are located on either side of the extensions 20. With this connection, the outer arm 12 can pivot with respect to the hinge tube 17 of coupling 13.
As best illustrated in FIGS. 4 and 5, the hinge tube 17 is provided with a central passage 23 which is disposed in alignment with the axes of arms 10 and 12.
Connected to the outer end of outer arm 12 is a tension spring 24. As best shown in FIG. 1, the end of outer arm 12 is located within the spring 24 and a clip 25 serves to connect the end of the spring to the arm. The outer end of spring 24 is provided with a loop 26 which is secured to the central portion of a U-shaped bale 27 by bolt 28. The ends of bale 27 are pivotally connected to the opposite sides of a shell or head 29 by studs 30. The pivotal connection of the bale 27 to the shell 29 permits the shell to be pivoted vertically and the pivotal connection of the bale to the loop 26 by virtue of bolt 28, permits the shell to be pivoted horizontally.
An electric light bulb 31 is threaded within a socket 32 mounted in the shell 29. To provide added protection against breakage, the light bulb can be supported within the shell by a resilient mounting mechanism not show. The socket 32 is connected to a suitable electric junction box by electrical leads that are housed within a cord 33. As shown in FIG. 1, the cord extends upwardly from the junction box within the hollow interior of the lower sleeve 7 and then through a plastic bushing 34 mounted in the wall of tube 5. The cord 33 extends through the hollow interior of arm 10, through the passage 23 in the coupling 13 and through the hollow interior of the outer arm 12. The cord then extends from the outer end of the arm 12, through spring 24 and then passes through a plastic bushing 35 in shell 29 and is connected to the socket 32 for the electric light bulb 31.
The coupling 13 is designed so that the arms of 10 and 12 can be pivoted with respect to each other without crimping, shearing or interfering with the electrical cord 33. The edges 36 bordering the ends of the passage 23 are rounded, and when the outer arm 12 is pivoted to the folded position with respect to the inner arm, as illustrated in FIG. 5, the cord will bend on the rounded edges 36 so that it will not be crimped during pivotal movement of the arms.
As the electrical cord 33 is completely contained within the light fixture from the mounting bracket 3 to the outer end of the spring 24, the appearance of the light fixture is improved, for it minimizes the amount of exposed cord and thereby decreases the possibility of the cord being caught on the mast of a lift truck or other object during the loading and unloading operations.
The light fixture is completely adjustable in that the arms 10 and 12 can be moved from the extended position, as shown in FIG. 1, in which the arms are in axial alignment, to a folded position in which the arms are parallel, as shown in FIG. 2. Moreover, the pivotal connection of the sleeves 7 with the lugs 4 permits the arms to be folded parallel to the wall. In addition to the adjustments of the arms, the head or shell 29 can be adjusted horizontally with respect to the axis of the arm 12.
The use of the tension spring 24 provides improved shock absorbing characteristics for the light fixture and enables the shell and other portions of the fixture to withstand substantial impact without danager of breaking of the light bulb or other components.
While the drawings illustrate the light fixture mounted on the wall of a building adjacent a loading area, it is contemplated that the light fixture can also be mounted on a post, a movable standard, or other supporting structure.
Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.
Copyright 2008−2012 Patents.com
