Abstract:
A mounting and lowering system for supporting one or more luminaires or similar devices having use within an indoor space or similarly configured space such as an open-air pavilion or the like, the system comprising a support assembly capable of being raised and lowered above a location within such a space not conveniently available for use in the servicing of luminaires or devices mounted by the system. The present system includes a latching mechanism permitting remote latching and unlatching of the support assembly. Vertical displacement of the support assembly can be effected without power interruption. Primary drive components are positioned within the system to facilitate service and replacement. The invention further contemplates transition apparatus capable of use in indoor spaces having differing ceiling angles.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application is a continuation-in-part of U.S. patent application Ser. No. 11/120,449, filed May 4, 2005, now U.S. Pat. No. 7,393,124 for “Architectural Mast-Mounted Support System”. 

   BACKGROUND OF THE INVENTION 
   1. Field of Invention 
   The invention relates generally to systems for hoisting utilitarian devices between use and service positions and particularly to such systems wherein a luminaire or cluster of luminaires are raised and lowered between use and service positions within an indoor or similar facility. 
   2. Description of the Prior Art 
   Luminaires and other utilitarian devices are often mounted indoors in dwellings, commercial and industrial buildings and even within the confines of structures such as open-air pavilions and the like in situations wherein access to the luminaires or other devices is impeded. In such situations, maintenance and repair are difficult due to the disposition of furniture, equipment and/or machinery inter alia directly below such luminaires or similar devices obviate the use of lift devices, ladders or the like for maintenance of such devices. In domestic situations, chandeliers or similar lighting fixtures are often mounted in spaces having furnishings and the like directly below such lighting fixtures, maintenance and lamp replacement not being possible except in a lowering of such fixtures to a height enabling access to the fixture or fixtures. Similarly, commercial situations such as retail stores, warehouses and the like have display cases, elevated shelving and other equipment located below lighting fixtures and other utilitarian devices with a result that access to such devices is difficult through use of ladders and the like especially in situations wherein the devices are located at substantial heights above the floor of such spaces. Industrial situations wherein machinery including chemical processing equipment and the like are located below luminaires mounted at heights above such machinery present additional though similar problems. In all such situations, personal safety must be considered when ladders and other expedients are used that require repair or maintenance personnel to ascend to the “in use” position of the lighting fixtures or other utilitarian devices mounted at heights above floor levels. 
   Systems intended to address the problems inherent in maintaining luminaires and the like in situations such as are noted herein have been devised previously, one such system being available from Aladdin Light Lift Incorporated for lowering chandeliers and the like, this system having all active components thereof mounted above a ceiling. Glebe, in U.S. Pat. No. 5,556,195 discloses a motorized system for lowering a luminaire from an “in use” position at or near a ceiling of a room to a maintenance position at or near a floor immediately below the “in use” position, the system including a cable to which a luminaire is connected and which is movable by an electric motor mounted above or on a ceiling. Glebe is distinguished from the Aladdin system by the ability of the Glebe system to function without interruption of electrical power to a winch/motor used to lower and then raise the luminaire in need of maintenance, repair or replacement. Pfaff, Jr., in U.S. Pat. No. 3,610,584, similarly discloses a luminaire lowering system wherein active lowering mechanisms are located above a ceiling as does Falls et al in U.S. Pat. No. 5,105,349 and Evans in U.S. Pat. No. 5,420,772. In these systems, service of active components of the lowering systems themselves is difficult due to the location of the active components such as motors, switches and electrical and mechanical connections inter alia either in enclosed locations above ceilings or in locations difficult to access for reasons similar to inability to access luminaires or the like such as initially requires use of these lowering systems. Lowering systems of varying description are also disclosed by Sakurai in U.S. Pat. No. 4,381,539; by Mier-Langner et al in U.S. Pat. No. 6,843,581 and by Weinhuber in U.S. Pat. No. 6,758,581. The prior art as represented by the foregoing systems as disclosed in the listed patents and as practiced in the disclosed systems are configured such that active components of such lowering systems are difficult to access for maintenance and repair. Further, lowering systems of the prior art as represented by the patents and systems referred to above are not susceptible to ready retrofit in existing buildings and, in any event, are configured to be disposed in essence only above or at a ceiling of a building. Still further, the lowering systems of the prior art do not provide positive latchment of one or more luminaires such as can be mountable to a lowering box or the like so that the luminaire or luminaires are mounted with an exceptional degree of stability when disposed in the “in use” position at or near a ceiling of a building. The prior art therefore remains in need of a lowering system useful in environments as referred to herein and which yields solution to previously unaddressed or unresolved problems inherent in the use of prior lowering systems, the present invention addressing such problems in a novel lowering system for single or multiple luminaires or similar utilitarian devices as disclosed herein. The present invention further addresses the need to accommodate mechanical elements of the present lowering systems to ceiling configurations having differing angles. 
   SUMMARY OF THE INVENTION 
   The invention provides hoisting systems for lowering a luminaire or clusters of luminaires mounted to a support frame in a ceiling of a building so that maintenance, repair or replacement can occur at a position at or near the floor of a building, the systems being particularly usable within buildings having ceilings or other structure from which said luminaire or luminaire-supporting structure is mounted in an “in use” position. The systems of the invention can be used with suspended, recessed or surface-mounted luminaires inter alia and with utilitarian devices other than luminaires. Buildings within which the present systems can be utilized include dwellings, commercial buildings and industrial buildings as well as open-air pavilions and the like, such structures typically having ceiling or roof structure to which a luminaire or other device is normally mounted. The systems of the invention further provide variable angle transition apparatus capable of causing mechanical elements to follow ceilings of differing configurations. 
   The systems of the invention find particular use in indoor environments and include winch and cable arrangements operable by motive power devices such as electrical motors, air motors and the like. Winch and motive power devices as used in the present systems are typically disposed on interior surfaces of walls of the buildings in which the systems are used, such drive systems of the systems also being positionable within such walls or externally of the buildings such as on exterior walls thereof. In open-air pavilions, such drive systems can be mounted to a suitable support plate or contained within a suitable housing. Drive systems of the present invention connect to a luminaire or cluster of luminaires or the like through wire cables that are caused to follow pulley and sheave arrangements, distal ends of such cables being connected to a luminaire-bearing support frame that mounts the luminaire or luminaires in a use position and being lowered on activation of the drive systems to displace said luminaire or luminaires to a maintenance position at or near a floor of the building. Cables including electrical power cables typically are disposed within conduit mounted against wall and ceiling surfaces, housings for the pulley and sheave arrangements connecting to such conduits being capable of modification to accommodate ceilings of differing configuration. 
   The support frame of the present lowering systems includes mechanisms capable of releasably and positively latching to cooperating structure carried by a stationary head frame permanently fixed to building structure at or near a ceiling, such structure comprising a latching mechanism employed to maintain the movable support frame to the stationary head frame when in a use position. The latching mechanism includes at least one cam-following pin slidable within a pin housing and mounted to the movable support frame, the pin engaging camming surfaces formed in a cam plate fixed to the stationary head frame. Each pin engages the camming surfaces on raising of the support frame into latching relation with the head frame, the pin sliding within the pin housing to assume a position whereby the support frame latches to the head frame. The support frame is raised slightly preparatory to lowering thereof by action of the motive power devices acting through the cables to disengage the support frame from the head frame, the support frame then being controllably lowered to a maintenance position near the floor so that luminaires or other devices mounted to the support frame can be maintained, repaired or replaced as necessary. 
   Latching mechanisms useful according to the invention can take forms other than referred to hereinabove. However, a particular latching mechanism preferably used according to the invention finds particular utility in that this latching mechanism is unlikely to jam during latching and unlatching operation. Use of the latching mechanism according to preferred embodiments of the invention more positively mounts the support frame and the luminaire or luminaires mounted thereto and thereby render an installation more safe. 
   Lowering systems configured according to the invention permit more ready access to motive power devices such as motors, winching devices and the like for service, replacement or repair being facilitated due to location of such devices in preferred embodiments at permanent positions at or near floor level proud of a wall of a building or interiorly of such a wall or even exteriorly of a wall. By so disposing the motive power devices at such locations, the present systems can be more easily used in retrofit situations. 
   The lowering systems of the invention find particular use in buildings wherein that floor space below the luminaire or other device mounted at or near ceilings is not accessible through use of ladders or lift systems. Such situations include in relatively simple forms a chandelier or the like disposed above a dining table or above stairs in a stair well. In commercial situations, luminaires or the like can be disposed over retail displays or elevated shelving in warehouses or the like. Industrial situations in which the lowering systems of the invention find particular utility include manufacturing facilities wherein machinery not readily movable is disposed below such luminaires. Particular situations include chemical processing plants such as petrochemical plants wherein explosive materials being processed require use of air motors rather than electrical motors as preferred motive power devices. The present systems thus find particular utility in hazardous locations. 
   Accordingly, it is an object of the invention to provide lowering systems particularly intended for indoor applications wherein a luminaire or similar utilitarian device can be lowered from an “in use” position at or near a ceiling to a maintenance position at or near a maintenance position below said “in use” position. 
   It is another object of the invention to provide a lowering system particularly intended for indoor applications whereby a luminaire or cluster of luminaires or similar utilitarian devices mounted to a support frame engaged to a stationary head frame located at or near a ceiling of a building can be released from the head frame and lowered to a maintenance position below an “in use” position, raising of the support frame to engage the head frame permitting positive latching of said frame together by means of a latching arrangement having a high degree of operational reliability. 
   It is a further object of the invention to provide lowering systems wherein motive power devices used to lower luminaires or similar utilitarian devices from an “in use” position above a building floor to a maintenance position at or near the floor are disposed on, in or exteriorly to a building wall. 
   It is yet another object of the invention to provide variable angle transition apparatus capable of housing pulley and cable arrangements necessary for operation of the present lowering systems to permit accommodation of ceiling conformations of differing configuration. 
   Further objects and advantages of the invention will become more readily apparent in light of the following description of the preferred embodiments of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a lowering system configured according to the invention wherein the system is used in a building having a flat ceiling; 
       FIG. 2  is an elevational view in section of a lowering system driven by an electrical motive power arrangement; 
       FIG. 3  is a detail view of a motive power arrangement used in certain embodiments of the lowering system such as is shown in  FIG. 2 ; 
       FIG. 4  is a detail view in section of a pulley and sheave arrangement of the lowering system of  FIG. 2  used to change direction at a right angle; 
       FIG. 5  is a detail view in section of a stationary head frame of the lowering system of  FIG. 2 ; 
       FIG. 6  is a detail view in section of a movable support frame of the lowering system of  FIG. 2 ; 
       FIGS. 7A through 7C  are detail views of a preferred latching mechanism used in the lowering system of the invention; 
       FIGS. 8A and 8B  are perspective views illustrating mounting of respective portions of the latching mechanism of  FIGS. 7A through 7C  to the movable support frame and to the stationary head frame; 
       FIG. 9  is an elevational view of a lowering system configured according to the invention wherein the system is used in a building having a vaulted ceiling, the building being a hazardous location such as for processing of petrochemicals or the like; 
       FIGS. 10A through 10D  are detail elevational views of portions of the lowering system of  FIG. 9 . 
       FIGS. 11A through 11C  are detail views of a variable angle transition capable of accommodating ceiling surface conformations of differing configuration; 
       FIG. 12  is a perspective view of a lowering system including the variable angle transition of  FIGS. 11A through 11C ; 
       FIG. 13  is a side elevational view of an installation having a sloped ceiling; and, 
       FIG. 14  is a side elevational view in partial section and partially cut-away of the transition of  FIGS. 11A through 11C . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The disclosures of U.S. Pat. Nos. 3,610,584; 5,556,195; 5,105,349 and 5,420,772 are incorporated hereinto by reference. The disclosure of U.S. patent application Ser. No. 11/120,449, filed May 4, 2005 and entitled “Architectural Mast-Mounted Support System”, of which the present application is a continuation-in-part, is incorporated hereinto by reference. 
   Referring now to the drawings and particularly to  FIG. 1 , a lowering system configured according to a first embodiment of the invention is seen at  10  to be comprised of a movable support frame  12  releasably latched to a stationary head frame  14 , the support frame  12  having one or more luminaires  16  mounted thereto and movable with the support frame  12  from an “in use” position as shown to a maintenance position below the “in use” position to a position at or near floor  18 . The head frame  14  is fixed to a ceiling  20  by means of suitable expedients (not shown) or to suitable structural elements (not shown) such as are conventionally disposed above a ceiling such as the ceiling  20 . The ceiling  20  is seen to be disposed at right angles to walls  21  of the space within which the system  10  is located. 
   The support frame  12  can mount utilitarian devices other than luminaires including speakers, heating and/or ventilation apparatus inter alia. Luminaires can be mounted to support arms or suspended from the support frame  12 , recessed thereinto or surface-mounted to said frame  12 . The support frame  12  can be configured to mount multiple luminaires or other utilitarian devices and functions with remaining portions of the lowering system  10  to lower the luminaires  16  and the like from an “in use” position at or near the ceiling  20  to a maintenance position at or near the floor  18  especially in operational situations wherein objects such as furnishings, equipment or machinery located beneath the luminaires  16  prevent use of ladders, lifts and the like to maintain the luminaires  16  and the like when located in the “in use” position. 
   The luminaire-bearing support frame  12  latches to the stationary head frame  14  by means of a latching assembly  24  not shown in  FIG. 1  but described in detail hereinafter, the latching assembly  24  preferably being identical with or similar to the latching mechanism disclosed in the aforementioned United States patent application incorporated hereinto by reference and of which the present patent application is a continuation-in-part. 
   As is best seen in  FIGS. 2 and 5 , the movable support frame  12  is lowered from an “in use” location adjacent the stationary head frame  14  by a suitable number of wire cables  26  carried one each by respective pulleys  28  mounted conventionally within the head frame  14  on opposite ends thereof. The cables  26  extend from the pulleys  28  through an open lower face of the head frame  14  and attach to the movable support frame  12 . The wire cables  26  enter the head frame  14  through an opening (not shown) in a side of the head frame  14  from a conduit  30  which houses the cables  26  between the head frame  14  and a fixed angle transition box  34 . 
   A power cord  32  extends into the head frame  14  from the conduit  30  preferably through the same opening (not shown) in the head frame  14  and is carried by a power cord sheave arrangement  36  mounted in the head frame  14 . The power cord  32  extends through the open face of the head frame  14  to a conventional attachment (not shown) in the movable support frame  12  for providing electrical power to the luminaires  16  (not shown in  FIG. 2 ). As is also seen in  FIG. 4 , the power cord  32  is housed within the conduit  30  along with the wire cables  26 , both the power cord  32  and the wire cables  26  extending into the transition box  34  through an opening therein (not shown), the power cord  32  and the wire cables  26  respectively being carried by an arrangement of sheaves  56  and a pulley  22  and change direction within the transition box  34  as seen in  FIG. 4  to extend downwardly from and out of the box  34  through an opening (not shown) in the box  34  and into conduit  38  mounted on or in proximity to a wall  21  of the space within which the lowering system  10  is located for use. The lowering system  10  is seen in a conformation wherein a transition of 90° must be accommodated due to the geometric relationship of the ceiling  20  to the wall  21 , that is, wherein the ceiling  20  is disposed at a right angle to the wall  21  in a conventional “flat” ceiling installation. 
   As can best be seen in  FIGS. 2 and 3 , the cables  26  and the power cord  32  extend through the length of the conduit  38  and into operative engagement with powered apparatus used to lower and raise the support frame  12  by means of the cable wires  26 . The conduit  38  is formed of a larger diameter than is the conduit  30  to allow housing of a clevis arrangement  40  to which the wire cables  26  connect. A winch and power unit  42  connects to the clevis arrangement  40  by means of a cable  41  and can be energized to lower and subsequently raise the luminaire-bearing support frame  12  for the purposes described herein. The clevis arrangement  40  also mounts a plug  44  terminating the power cord  32 , the plug  44  being connectable to a source of power for operation of the luminaires  16 . The clevis arrangement  40  connects to conventional mechanical expedients driven by a worm drive winch  46  operable by a motor  48 , preferably an electric motor preferably in situations wherein an explosive atmosphere is not present. The motor  48  is conventionally operated by a manually-controlled reversing switch  54 . 
   A support tray  52  is secured to a receiver box  50  (shown in section for ease of illustration) by means of a pin (not shown) when the system is in a raising/lowering configuration. The tray  52  mounts the winch and power unit  42 , this structure being removable when not in use. When removed, a cover (not shown) can be placed over the box  50 . In  FIG. 3 , the conduit  38  is shown removed for ease of illustration. 
   As best seen in  FIGS. 2 and 3 , a cable  53  having a hook  55  attached to a free end thereof is connected to the receiver box  50  for mating with clevis  51  of the clevis arrangement  40 . Connection of the hook  55  to the clevis  51  occurs on removal of the winch and power unit  42  when the unit  42  is not in use. The cable  53  and hook  55  performs a safety function. 
   Referring again to  FIG. 5 , the pulleys  28  respectively function to each carry one each of the wire cables  26  that extend from the head frame  14  and connect to the support frame  12  so that the support frame  12  can be raised and lowered on operation of the motor  48 . The power cord  32  is carried by sheaves  59  of the power cord sheave arrangement  36 , the cord  32  extending to the support frame  12  and electrically connecting to the luminaires  16  to provide power thereto as previously noted. Although not configured for such function as shown in  FIG. 5 , the power cord  32  can be paid out as the support frame  12  is lowered to continue electrical power, if desired, to the luminaires  16  during raising and lowering of the luminaire-bearing support frame  12 . The pulleys  28  and the sheaves  59 , as well as the pulley  22  and sheaves  56  mounted for function within the box  34 , are mounted conventionally for rotational movement. 
   Referring now to  FIGS. 6 and 7A  through  7 C, the latching assembly  24  is seen to be comprised of a latch pin  80  mounted for sliding movement within a pin housing  82 , the pin housing  82  being carried by the support frame  12 . The latching assembly  24  is further comprised of a cam latch plate  84  mounted to the stationary head frame  14 . A camming pattern  86  is formed in the latch plate  84 , the pattern  86  being recessed into the plate  84 . On engagement of the latch pin  80  with the latch plate  84 , the pin  80  engages camming surfaces  88  of the camming pattern  86  formed in the latch plate  84  and follows the pattern  86  on upward movement of the support frame  12  relative to the stationary head frame  14 . The support frame  12  thus latches to the head frame  14  through the agency of the latching assembly  24 , the structure and operation of the latching assembly being described in detail in U.S. patent application Ser. No. 11/120,449, filed May 4, 2005, of which the present patent application is a continuation-in-part and the disclosure of which is incorporated hereinto by reference. The latching assembly  24  permits unlatching of the support frame  12  from the stationary head frame  14  for lowering of the support frame  12  for purposes noted herein. 
   As seen best in  FIGS. 8A and 8B , the pin housing  82  within which the latch pin  80  is capable of sliding movement is mounted to the support frame  12  while the latch plate  84  is mounted to the head frame  14 . Two of the latching assemblies  24  are preferably used to releasably latch the support frame  12  to the head frame  14 , the two assemblies  24  acting in concert to provide latching and unlatching functions. As can be appreciated in light of the intended scope of the invention, latching assemblies other than the latching assembly  24  can be employed to accomplish the latching and unlatching functions necessary to practice of the invention. In  FIG. 8A , the latching assemblies  24  are shown in the unlatched configuration while  FIG. 8B  shows the latching assemblies  24  in a latched configuration. 
     FIGS. 9 and 10A  through  10 D illustrate a lowering system  60  particularly usable in hazardous environments such as in a petrochemical plant wherein gases and other combustible material present an explosion hazard in the event of a spark from an electrical appliance such as an electrical motor. In such situations, an air motor (not shown) is used in place of the motor  48  of  FIG. 1 . The lowering system  60  is seen to be located in an installation wherein ceiling  62  is vaulted, transition box  64  therefore being configured to provide a transition between conduits  66  and  68  of greater than 90°. A transition box  70  is provided at the end of the conduit  68  to permit location of a horizontal conduit  72  that extends to stationary head frame  74  mounted to building structure, the head frame  74  being oriented horizontally and being releasably joinable to a movable support frame  76 , the head frame  74  and the support frame  76  being essentially identical to the head frame  14  and the support frame  12  shown in  FIG. 1 . The lowering system  60  through agency of the fixed angle transition boxes  64  and  70  permit installation in a situation wherein the ceiling  62  is an angled ceiling. 
   The boxes  64  and  70  seen best in  FIGS. 10C and 10D  respectively can be configured to be air-tight, if necessary, to negate the destructive effect of any spark generated by passage of wire cables (not shown in  FIGS. 10C and 10D ) over sheaves and/or pulleys (not shown) contained within said boxes  64  and  70 . Housing  63  seen in  FIG. 10A  has a housing cover  61  that opens to expose a winch and power arrangement (not shown) to include an air motor or the like.  FIG. 10B  illustrates a mounting arrangement  65  for maintaining the conduit  66  in place. 
   Referring now to  FIGS. 11A through 11C , and  12  through  14 , a lowering system  100  is seen in  FIGS. 12 and 13  to be installable in situations including flat ceilings such as ceiling  120  of  FIG. 12  and angled ceilings such as ceiling  162  of  FIG. 13 . A variable angle transition box  150  can be seen in each of the  FIGS. 11A through 11C  and  12  through  14 , the box  150  being seen in  FIGS. 11A ,  12  and  14  in a configuration wherein a 90° transition is required due to a flat ceiling  120 . In  FIGS. 11B and 13 , the box  150  is configured to accommodate sloped ceiling  162 .  FIG. 11C  illustrates the structure of the transition box  150  that permits accommodation of essentially any angled ceiling ordinarily encountered in conventional buildings. 
   Referring first to  FIG. 11C , the transition box  150  is formed of a housing seen generally at  152  to be formed of upper plates  154  and  156  mounted for rotation relative to each other, the plates  154  and  156  forming one side of the housing  152 . The plates  154  and  156  each have substantially circular base elements  158  and  160  respectively and respective extensions  162  and  164  each having flanges  166  and  168  extending outwardly from free ends of the extensions  162  and  164 . The plates  154  and  156  are mounted to pivot relative to each other about a central axis formed by a central pin  172  that also mounts pulley sheaves  174  for rotation within the box  150 . The pin  172  also mounts lower plates  176  and  178  for pivotal movement relative to each other in concert with pivoting movement of the upper plates  154  and  156 . The lower plates  176  and  178  are each provided with respective extensions  180  and  182  which have flanges  184  and  186  respectively extending outwardly from free ends thereof. The extensions  180  and  182  are each further provided with opposing walls  188 ,  190  and  192 ,  194 , each of the walls  188 ,  190 ,  192  and  194  having inwardly extending flanges  196 ,  198 ,  200  and  202  formed on upper free edges thereof. End plates  204  and  206  respectively join to respective ends of the joined upper plates  154 ,  156  and lower plates  176 ,  178  to enclose said ends. Curved walls  208 ,  210  and  212 , preferably segmented for ease of manufacture and operation, act to enclose annular regions about the periphery of the box  150  at those locations not enclosed by the walls  188 ,  190 ,  192  and  194  of the lower plates  192  and  194 . The curved walls  208 ,  210  and  212  slide relative to the plates  154 ,  156  and  192 ,  194  on pivotal movement thereof to configure the box  150  to accommodate angled ceilings from at least 90° as seen in  FIG. 12  to obtuse angles as seen in  FIG. 13 . A single transition box  150  therefore accommodates differing angles as is necessary to configure particular ceiling installations. 
   As best seen in  FIG. 11C , the end plates  204  and  206  have openings  214  and  216  formed respectively therein to receive conduits such as the conduits  130 ,  138  or conduits  166 ,  168 ,  172  through which cable wires  126  and a power cord  132  extend into the interior of the box  150  to thread respectively over a pulley  174  and a sheave arrangement  218  as has been described herein relative to other embodiments of the invention. Mounts  220  connect the conduits  130 ,  138  or conduits  166 ,  168 ,  172  to the box  150  and to walls. The lowering systems  100  and  160  are driven by apparatus such as has been described herein relative to the lowering systems  10  and  60 . 
   Although the lowering systems of the invention have been described relative to particular embodiments thereof, it is to be understood that the invention can be embodied other than as expressly shown and described herein, the scope of the invention being defined by the appended claims.