Tower Light System

The invention is concerned with high level mounting of beacons, as signal lights or other warning signal fixtures, on TV and radio towers and other stabilized elevated structures requiring such signal fixtures at the top portion thereof. Repair or replacement of such fixtures has presented the problem of danger to service personnel in climbing to and from such elevated locations, such dangers being increased during inclement weather, if not rendering servicing impossible during such conditions. Insurance rates have been high under such conditions as well as the expense of repair at such elevated locations, normally based on a dollar amount per footage. Efforts to alleviate these problems have been made such as the provision of unitized replacement fixtures at pole ends (U.S. Pat. No. 3,679,891); cable and like mechanisms for lowering the fixtures, as flood lights (U.S. Pat. No. 3,686,498; U.S. Pat. No. 3,856,639), and signal lights (U.S. Pat. No. 3,292,322). However, the expenses of such mechanical details must be considered.

According to the present invention, the assembly includes a light or other signal fixture mounted on a carriage which is movable between an upper signal emitting position relative to the tower or other elevated structure, and a lower position relative to the tower affording ready access to the fixture for repair, replacement or other servicing, either at ground or low support level, thus eliminating the necessity for climbing to dangerous heights for such servicing. Provision is also made for automatic energization of the signal fixture at the upper operative position thereof, and for disconnecting the fixture from its energizing source upon descent thereof to a lower accessible servicing position, thus eliminating danger to servicing personnel, as from electric shock or the like.

An object of the invention is to provide an assembly substantially of the above type wherein the elevating and lowering mechanism for the carriage is substantially free from the effects of weather conditions, such as wind, snow, freezing conditions and the like.

Another object of the invention is to provide such an assembly including a substantially sealed tubing arrangement in supported association along the height of the tower or like structure, and within which tubing arrangement the carriage and included fixture may be elevated to operative position adjacent the top of the tower or like structure by fluid pressure, with permissive release for descent thereof to an accessible servicing position.

A further object of the invention is to provide such an assembly with automatic energization of the fixture at the upper operative position thereof and disconnection of the operation of the fixture upon descent thereof to the lower accessible position.

The above and other objects of the invention will in part be obvious and will be hereinafter more fully pointed out in the description of the drawings in which:

FIG. 1 is an elevational view of a tower structure with the elevator tubing arrangement in association therewith;

FIG. 2 is an enlarged fragmentary perspective view of the lower portion of the tubing arrangement with the light access opening exposed;

FIG. 3 is a further slightly enlarged section view of the upper portion of the tubing arrangement with the carriage and light fixture in operative position; and

FIG. 4 is a similar view, partly in section, of the lower portion of the tubing arrangement with the carriage and fixture in the lower position for access.

With reference to the accompanying drawings, and particularly FIG. 1 at this time, the tower structure may be of suitable stabilized construction and is illustrated as including upstanding inclined support legs 10 of tubular or solid steel, aluminum or similar material and substantially braced and connected by an array of diagonal brace elements 12. In addition, there may be provided horizontal bracing members 14 joining a sealed tube 16 and the legs and bracing elements for stable support along the length of the tower. The top of the tubing arrangement is closed by a glass casing 18 through which the light in its upper position will be visible as a beacon. The lower end of the tubing is closed by a bottom cover 20 and a lower part of the tubing is provided with an access opening sealingly closed by a closure 22. A lower transverse member 14a may serve as a support platform at a reasonable and safe height above ground level for servicing the fixture upon opening the closure 22. In this connection, the door 22 is shown opened in FIG. 2 for access to the light bulb 24 or other signal which is supported by the carriage, and is provided with a trim gasket 25 for sealing around the access opening when closed. The opening is sized according to the size of the fixture to be serviced as by operator hand insertion thereinto.

With reference to FIGS. 2 and 3, the service operator may remove and replace the bulb 24 by hand through the access opening as shown in FIG. 2. The bulb is mounted in a threaded socket 26 welded or otherwise suitably secured to the carriage 28 which is in the form of a piston or plunger with upper and lower flanges 30, 30a closely adjacent the interior wall of the cylindrical tubing. The lower flanges 30a has suitably secured thereto a gasket 32 in sliding friction sealing contact with the interior wall of the tubing. Upon replacement or other servicing of the signal fixture 24, the door 22 is closed to seal the tube and a preferably gaseous fluid, e.g., air, under pressure from a suitable source (not shown) is flowed through conduit 34 to the lower portion of the tubing 16 beneath the carriage flange 30a. For this purpose, the conduit 34 may have a suitable quick connect and disconnect coupling to valve V.sub.1 housing 36 for an open-closed type of valve manipulated at this time by handle means 36a to open position. Also at this time, an open-closed type of exhaust valve V.sub.2 in housing 38 is closed by handle means 38a.

Ingress of fluid under pressure will act on the carriage 28 through its gasket 32 seal with the tubing 16 until it reaches the upper position shown in FIG. 4 to which reference is now made. In this elevated position of the carriage and included light fixture, the carriage flange 30, or other abutment, will engage a stop 40 interiorly at the upper end of the tubing, and a spring 42 pressed plunger 44 of solenoid 46 will have been urged outwardly by the carriage flange 30, or other abutment, passing by the beveled edge thereof and will then be spring urged into the position of FIG. 3 underlying the carriage flange 30, or other abutment, to latchingly hold the carriage and included fixture in the uppermost signaling position. Then, either automatically by interlock, or by hand, valve V.sub.1 will be closed and the fluid pressure source disconnected.

In arriving at this upper position of the carriage, trapped air in the tube will vent through opening 48 which may be louvered for protection against weather conditions. Suitable electrical connections are provided from a wired power source 50 to the bulb and socket and include a switch mechanism with resilient contacts 52, 54 insulatedly extending through the tubing. Each contact will resiliently engage a conductive (copper) ring 53, 55, respectively, arranged concentrically on an insulating surface 57 on the top surface of the piston, if made of metal. However, the piston may be formed of a non-conductive material consistent with desired weight characteristics for efficient ascent and descent operation, in which case the insulating surface 57 is not required. Thus, the circuit to lamp 24 will be completed at the upper position of the carriage (FIG. 4) and both contacts are resilient to assure continuity of contact even though there may be some lost motion of the carriage flange 30 between the stop 40 and the plunger latch 44. The carriage may be guided within the tube for rectilinear movement therealong to insure switch contact but if there is some relative rotation between the carriage and the tubing during ascent, the contact rings will insure contact with a respective switch element 52, 54.

When it is necessary to service the light fixture, a key 56 (FIG. 2) may be manipulated in on-off switch 58 to energize solenoid 46 (through suitable wiring connections 60) to withdraw plunger 44 against the action of spring 42 and thus free the carriage flange 30 for descent to the lower accessible position (FIGS. 2 and 3). Initial descending movement of the carriage will break the contacts, 52, 54 and deactivate the light. The exhaust valve V.sub.2 is selectively opened for this descending movement of the carriage and this movement is resisted by sliding friction of the carriage gasket 32 with the tubing and under abnormal conditions, the valve V.sub.1 may be manipulated to admit fluid under pressure to control descent, if necessary. The operation will be apparent from the foregoing description and the tubing may be formed of suitable material, such as aluminum tubing in sections joined as illustrated by collars or the like to the horizontal tower elements or otherwise for stable support. For example, a tubing arrangement may serve as the sole support for the light fixture as well as an elevator, as in street or highway lighting, and similar installations.

While shown for illustrative purposes, it will be understood that variations in details and arrangement of parts may be made without departing from the scope of the invention as set forth in the appended claims.