The invention is generally directed to a portable studio hoist for use in raising and lowering lighting and other items from the pipe grids used in television studios, which are generally suspended from the building structure. The portable studio hoist is utilized to move studio lighting fixtures, which are affixed to the pipe grid vertically between the floor and the pipe grid. It may also be used to move lighting fixtures and other loads in other settings secured to appropriate fixed structural locations
Generally, existing hoists in theater and studio applications are intended for permanent installation, and typically, because of their size, weight and power requirements, must be installed as part of the building construction project. The hoists are affixed to the building's structural steel and permanently wired with three-phase power and a hard wired control circuitry, usually utilizing conduit wiring to meet building codes and electrical codes for permanent installations. As a result, the location of moving pipes must, therefore, be anticipated in the design process when a theater or studio is being built.
However, most U.S. television studios are equipped with pipe grids. These are static pipe structures suspended from the building structure. In turn, studio lighting fixtures are affixed to this grid. The fixtures are frequently moved and adjusted, requiring operators to climb ladders for access. Generally, standard hoists can only be added to the building steel or with the addition of structural steel because the pipe grid does not have sufficient weight bearing capacity to support the weight of these hoists, and lifted weight, which generally run about 750 or more pounds.
The pipe grids are typically equipped with lighting power distribution strips carrying power to all locations on the grid. This permits optimum flexibility for the lighting. The power, however, is single-phase 120 VAC, which is sufficient for the lighting. If a typical hoist is added to this system, three-phase power must be run to that location, which becomes a fixed location for that hoist. Accordingly, there is a need for an improved hoist that can carry a modest payload, up to about 300 pounds, and could be quickly moved anywhere on a grid and be quickly provided with existing power. That need is typically only identified by the studio operators after the studio has been built and in use for a time and, thus, there is also a need for the portable hoist to be of a sort which can be brought to a site when and as needed or be rented from a lighting rental house, together with studio lighting fixtures. It is also necessary to develop a portable hoist system which can be moved around the grid to areas where workers are either adding, removing or modifying studio lighting fixtures in connection with a production.
The invention is generally directed to a portable studio hoist, which includes a mechanism for removably connecting the portable studio hoist to the pipe grid structure used in television and theatrical studios and performance venues, which allows studio lighting fixtures to be raised and lowered from the grid to different operating positions and the floor safely and without the need for dedicated wiring or structural modifications to the theater and studio to support the hoist.
The invention is also directed to a portable hoist incorporating a removable shaft associated with the motor so that the end user can modify the shaft depending upon its specific application without affecting the performance or operation of the portable hoist. The portable hoist can also be controlled remotely via a light-weight, low power and voltage remote, either directly or through a remote control center into which one or more portable hoists at a site may be controlled.
Accordingly, it is an object of the invention to provide an improved portable hoist to improve access to lighting fixtures and efficiency of broadcast studios by allowing studio lighting fixtures to be raised and lowered from the pipe grid without having to bring in special power or structural elements to the pipe grid.
It is another object of the invention is to provide an improved portable hoist for use in theater and studio applications utilizing a single-phase 120 VAC current which may be removably secured to the pipe grid wherever it is needed without the need for special tools or additional installation hardware.
Yet another object of the invention is to provide an improved portable hoist which includes a motor with a shaft that is removable and replaceable with shafts of different lengths to adapt for different batten lengths and other conditions.
Still another object of the invention is to provide an improved portable hoist in which the shaft may be replaced by the end user without affecting the operation of the hoist.
Yet still a further object of the invention is to provide an improved portable hoist which may be connected either parallel to the standard pipes of the pipe grid or at an angle to the pipe grid so as to provide enhanced flexibility of positioning of the portable hoist.
Another object of the invention is to provide a hierarchical system of connecting a series of portable hoists to a pipe grid or similar structures where the portable hoists are connected to a control hub, which in turn can be connected to a selector station and operated by use of a pendant controller.
Still yet a further object of the invention is to provide a system of connecting a series of portable hoists to a pipe grid or similar structures where the portable hoists are connected to a selector station and operated by use of a pendant controller.
Still other objects and advantages of the invention will, in part, be obvious and will, in part, be apparent from the specification.
The invention accordingly comprises the features of construction, combinations of elements and arrangements of parts which will be exemplified in the construction as hereinafter set forth, and the scope of the invention will be indicated in the Claims.
For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawings, in which:
The portable hoist was developed to address the need for a safe, low cost and portable hoist to improve access to lighting fixtures and efficiency of broadcast studios. While existing hoists in theater and studio applications are intended for permanent installation and typically must be installed as part of the building construction project, the portable studio hoist constructed in accordance with a preferred embodiment of the invention is easily movable and portable in existing studios.
In a preferred embodiment the portable studio hoist weights only about 90 pounds and can be moved by two stage hands anywhere on the pipe grid found in most U.S. television studios and many theatrical and other studio installations. The compactness, light weight and connection details are specifically designed for attachment to a standard 1½ inch schedule 40 pipe grid. The portable studio hoist can also be attached to other installations, other than a pipe grid with suitable connectors. The portable studio hoist can be attached parallel to the pipe grid members or at an angle to the pipe grid members, providing maximum lighting position control. To the extent that alternative grid sizes or arrangements are found in other applications and other countries where different standards for pipe grids or similar rigid structures for supporting lighting and the like are found, minor adaptations to the connection hardware can be made without changing the effectiveness of the portable hoist.
The portable studio hoist is an electromechanical system that is specifically designed to move scenery, lights and/or other equipment in a vertical plane. It is designed with built-in safety factors and safety features. It operates on a single-phase 120 volt power. Its single phase power requirement permits it to obtain utility power directly from the lighting distribution raceways, which permit location and relocation anywhere on the grid. In alternative environments its suitability with standard single phase utility power and without hardwired power connections allows considerable flexibility and usefulness. In a current preferred embodiment the portable studio hoist system consists of one or more compact studio portable hoists that mount to the 1½ inch schedule 40 pipe grid. Power to each portable studio hoist is via a non-dim circuit at local connector strips or local utility power. Generally, a limit of one portable studio hoist per non-dim circuit is preferred. The control to the portable studio hoist is via a control hub located at the grid and a selector station with a remote pendant located at the deck level. All connections are soft cable “plug and play” systems. The control hub is a plug-and-receptacle station for preferably eight but up to ten or more portable studio hoists. In some installations multiple control hubs are used for convenience and to minimize the distance of connecting lines between the hoists and the control hub. The selector station contains a position switch and position indicators (service, play and storage) for each portable studio hoist, an e-stop (emergency stop) button and a keyed power switch. The remote pendant includes an e-stop button, power indicator light and momentary contact “run” button. In small installations with one or two portable hoists, a powered selector station can be used without the control hub, although this does not realize some of the benefits of the control hub in the system.
The portable studio hoist's hollow shaft gearbox provides dual cable suspension for greater payload stability. This feature also allows a longer shaft to be added into the system to support batten lengths up to six feet. Wider drums providing greater travel are also an option. Drums are solid 6063 anodized aluminum for easy assembly. Additional shaft, batten and drum kits (including a T-shaped guide) are available for use. Cable retention clamps allow lift lines to be easily replaced during routine maintenance procedures, or if lift lines are damaged. The T-shaped urethane cable guide rollers keep lift lines in place on the drums. The new T-shaped urethane cable guide rollers developed in connection with the invention support the variable drum feature. Contrary to other hoists which can generally only support a change of batten length up to about 20% longer but no shorter, the portable studio hoist constructed in accordance with the invention permits the batten length to nearly double to 6 feet, and for distance between pickup points to be altered, and for the vertical travel to be increased, these alterations being simple enough to perform with factory supplied parts so they can be performed in the field by reasonably sophisticated users. Such alterations would not be possible with existing hoists.
The portable studio hoist contains the following: 1) a motor which provides the force to move the load; 2) a gear box which reduces the speed of the motor and multiplies the torque; 3) a drive shaft to transmit force to the load; 4) an AC motor drive to control voltage to the motor; 5) a series of remote pushbuttons to operate the portable studio hoist; 6) a system of limits which is factory preset but is customizable; and 7) a system of lifting cables spooled on drums that attach to a short batten to support the load.
The general specifications in accordance with the current preferred embodiment of the invention are that a 15 amp service is required for each of the portable studio hoist and control hub. The motor is, in one preferred embodiment, a one and one half horsepower motor requiring a voltage of 120 VAC, one-phase at 60 hertz. The hoist capacity is rated at 300 pounds and the portable studio hoist unit's self weight is about 90 pounds. The batten travel is up to about 25 feet with the batten speed of about 14 feet per minute in a current preferred embodiment. There are pre-sets for play/storage/service with over travel limits for up, down. The lifting cables are ⅛ inch Galvanized Aircraft Cable (GAC).
For installation and operation it is important that one first verify that the voltage to each power source for the control hub and portable studio hoist is 120 VAC. Confirm that the power is off at the non-dim circuit or circuits assigned to the control hub and portable studio hoist(s). Clamp the control hub to the pipe grid in the desired location. Mount the selector station at deck level. Mount it securely to prevent the unit from falling or dropping. Next, mount the portable studio hoist or hoists onto the pipe grid in desired locations. Clamp the portable studio hoist to the grid using load-rated hardware. Connect the control wiring by connecting the control cables from the control hub to the portable studio hoist and then connect the main control cable from the control hub to the selector station. The selector station receives its power in the main control cable from the control hub. In configurations where there is no hub the selector station is directly connected to a local utility outlet. Connect the power wiring by plugging each portable studio hoist power cable into a non-dim circuit or utility outlet with a limit of one portable studio hoist per 15A non-dim circuit. Then plug the control hub into a 15A non-dim circuit. It is important with the current equipment not to plug the equipment into dim-able circuits which might result in damage to the equipment. Next, power is turned on at the non-dim circuit or circuits assigned to the portable studio hoists, the selector station is turned on. The power indicator light will then verify that the system is energized. If it is, then the pendant is plugged into the selector station, the portable studio hoist selected and its direction of travel of the load selected using the toggle switches on the selector station. The “run” pushbutton is pushed to operate the portable studio hoist, which will run until it reaches it's limit switch. The “run” pushbutton can be released at any time to stop the portable studio hoist. The red emergency stop pushbutton is used to stop the portable studio hoist in case of emergency. Generally, it is recommended that the toggle switches be returned to the stand-by position and the selector station be turned off when the portable studio hoist is not in use.
To operate the portable studio hoist safely it is important to familiarize oneself with the operation and, prior to loading the batten or adjusting the play position limit switch, to run the batten full travel in both directions to verify that factory set limit switches are correct. It is important to not allow the batten terminations to run into the drum.
Next, evenly distribute the load on the batten and, prior to operating, check the load and look for places where the load could foul during its travel.
Setting the limits on the portable studio hoist is user accessible. The limits are set with a factory set up and down ultimate (or over-travel) limits, factory set storage (normal up) limit, service limit (normal down) and mid-range play limit. The ultimate, service and storage position limit switches protect the portable studio hoist from damage and should not be changed.
Reference is made to
The objects to be hoisted or maintained in position by portable studio hoist 100 are secured in a traditional fashion to batten 110. Batten 110, which includes batten end caps 111, is in a first preferred embodiment, 3 feet long. However, the batten length can be adapted and increased depending upon the needs of the object, such as a studio lighting fixture which are to be affixed to it for raising and lowering. In preferred embodiments, the shaft 105 can be substituted out with a different shaft of greater length, with the drums 106 and T-shaped guides 113 on either end of shaft 105 repositioned for a wider support of a batten 110 of a greater length such as six feet.
With reference to
Cable retainer 113, which has a generally T-shaped orientation with a thin connection to shaft collar 107 and sleeve 102 and includes twin urethane rollers exerts pressure against aluminum drum 106 to keep the cable 108, which, in a preferred embodiment, is ⅛th inch, 7×19 GAC, again, in a preferred embodiment, having a length of about 25 feet. The cable 108 is wound around each of the drums 106 and held in place so that it reliably and safely winds around drum 106 held in place by the cable retainer 113. Cable retainer 113 is generally in a conventional fashion biased against the cable 108.
Gear motor 101 is supported by mounting plates 120 seen in
Reference is next made to
Reference is next made to
The pendant 400 as shown in
However, in another preferred embodiment of the invention, pendant 400 can be a more complex arrangement including a touch screen in which the operator can exercise control of the hoists to be selected and operated on the pendant. The hoist selector station 300, for control by the touch screen pendant includes additional circuitry to allow this remote control of the selection. In addition, hoist selector station 300 is shown as connecting to a single hoist control hub 200. In other preferred embodiments, single hoist selector station 300 can be connected to a series of different hoist control hubs 200 in larger installations. Thus, rather than merely controlling 6 or 8 or 10 hoists from a single selector, an entire bank of 24 or 36 or other number of hoists can be connected to two or more control hubs 200 which can be controlled from a single selector station 300 and utilizing a single pendant 400.
As described above, a series of different control hubs 200 may also be connected to a single selector control outlet 300 depending upon the needs of a particular job. Generally, when a large installation with the capacity for many portable studio hoists is installed in a studio, a series of control hubs 200 are spaced and fixed throughout the pipe grid in a fashion which allows the lighting designers and others to hook up portable studio hoists to a relatively close control hub 200 as the hoists are secured to the pipe grid. Similarly, in large installations, the selector control unit 300 will likely be placed in an electrical enclosure. Such enclosure would be secured by a lock that would prevent unauthorized access to the hoist control system. Again, in larger installations, pendant 400 may also be enhanced to provide additional control at the pendant, rather than at the selector control unit. In large installations, the connections from the selector station 300 to pendant 400 can be enhanced so that connections to various locations around the studio are hard wired, so that the pendant control cable 405 is plugged into connectors which are distributed around the floor, rather than having a long cable which snakes all the way from the selector station 300 to the desired location. In this way the pendant control cable 405 can be made shorter and problems with a long cable avoided.
Reference is next made to
Accordingly, an improved portable studio hoist, which can be easily manipulated and maneuvered by one or two stage hands and then moved around the pipe grid of a television or theatrical studio to raise and lower studio lighting appliances and other relatively moderate weight items without the need for a dedicated hoist with permanent wiring and to provide hierarchical control of the portable studio hoists from a single control panel is provided. Additional configurations of hoists with the use of 120V AC power which can be moved around and organized with decentralized control hubs and a centralized selector station operated by a pendant is provided.
It will thus be seen that the objects set forth above, among those made apparent in the preceding description, are efficiently obtained and, since certain changes may be made in the above constructions without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative, and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention, herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.
This application claims the priority of provisional application Ser. No. 60/559,208 filed in the United States Patent and Trademark Office on Apr. 2, 2004.
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Number | Date | Country | |
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20050231148 A1 | Oct 2005 | US |
Number | Date | Country | |
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60559208 | Apr 2004 | US |