Abstract:
Methods and apparatus for a lift system for translating equipment mounted on a vehicle between an operational position and a servicing position is provided. The lift system includes a support frame fixedly mounted to the vehicle, a transport member slidably coupled to the support frame, and a lift platform coupled to the transport member wherein the lift platform is configured to support the equipment in the operational position and in the servicing position.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is entitled to the benefit of, and claims priority to, provisional U.S. Patent Application Ser. No. 60/728,718, filed Oct. 20, 2005 and entitled “Hydraulic Assist For The Servicing Of On-Board Fire Suppression Systems,” which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention generally relates to fire suppression systems and more particularly, to methods and apparatus for maintaining fire suppression systems. 
         [0003]    Fire suppression systems that are installed on mobile platforms present a unique problem when servicing is required. Service may include, but not be limited to, recharge of agents, pressurizing cylinders, and hydro-testing of tanks. At least some known systems require maintenance personnel to climb onto the vehicle to conduct such service, using, for example, ladders, fold-down steps, both of which may be integral to the vehicle, or the use of external devices to allow access to the roof of the vehicle. Such approaches put personnel at risk of falling from vehicles, lifting heavy objects under elevated conditions, and otherwise placing personnel in awkward positions on unstable platforms. For example, personnel are required to climb on-board the platform to conduct recharge and refilling operations or other scheduled maintenance items. 
         [0004]    Solutions to such problems have included the use of personnel protective equipment, most notably safety harnesses and the use of grab rails to provide support. In general, passive protection is applied to protect personnel while the fire suppression system is maintained in a fixed position. However, the standard practice has not eliminated the hazards associated with servicing on-board systems at elevation, but rather attempt to insure personnel are protected from injury using protective equipment. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0005]    In one embodiment, a lift system for translating equipment mounted on a vehicle between an operational position and a servicing position is provided. The lift system includes a support frame fixedly mounted to the vehicle, a transport member slidably coupled to the support frame, and a lift platform coupled to the transport member wherein the lift platform is configured to support the equipment in the operational position and in the servicing position. 
         [0006]    In another embodiment, a method for gaining access to equipment that is positioned remotely during operation is provided. The method includes operating the equipment in an operational position on a vehicle, moving the equipment to a servicing position on the vehicle to perform maintenance on the equipment wherein the servicing position provides greater access to the equipment than the operational position. 
         [0007]    In yet another embodiment, a vehicle for transporting equipment includes an enclosure housing the equipment, a support frame fixedly mounted to the vehicle, a transport member slidably coupled to the support frame, and a lift platform coupled to the transport member wherein the lift platform is configured to support the equipment in an operational position and a servicing position. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a side schematic view of an exemplary vehicle, such as an emergency response vehicle, in accordance with an embodiment of the present invention; 
           [0009]      FIG. 2  is a rear schematic view of the vehicle shown in  FIG. 1 ; 
           [0010]      FIG. 3  is a side schematic view of another exemplary embodiment of the vehicle shown in  FIG. 1 ; and 
           [0011]      FIG. 4  is a rear schematic view of another embodiment of the vehicle shown in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0012]      FIG. 1  is a side schematic view of an exemplary vehicle  100 , such as an emergency response vehicle, in accordance with an embodiment of the present invention. In the exemplary embodiment, vehicle  100  includes wheels  102  coupled to a frame  104  through a suspension system (not shown). Vehicle  100  also includes an occupant cab  106  and an equipment enclosure  108  for housing equipment, for example, fire-suppression equipment, such as a tank  110 , a tank  111 , and a pump  112 , which may be driven by an engine  114  housed in an engine compartment  116 . In an alternative embodiment, pump  112  may be driven by a portable engine  117 . Equipment enclosure  108  also includes lockers  118  for storing personnel protective equipment, consumable items and tools. As described herein, the term “vehicle” may be used to refer to a self-powered apparatus that may travel through the air, water, and/or on or under the ground. For example, vehicles may include vans, trucks, railcars, tracked vehicles, water craft and aircraft. Additionally, “vehicle” also refers to un-powered conveyances that are normally pulled or towed, for example, trailers, carts, skids, barges, gliders and the like. 
         [0013]    Vehicle  100  also includes a lift assembly  120  that substantially reduces the need for personnel to climb on-board vehicle  100  to conduct maintenance activities. In an operational condition, the fire-suppression equipment requiring service is typically located in a restricted access location, such that it is protected from the environment during transit and operation. In the exemplary embodiment, vehicle  100  utilizes lift assembly  120  to position the fire-suppression equipment requiring service in a position outside of outer perimeter of enclosure  108  and/or outside an outer perimeter of vehicle  100 . Servicing can then be conducted from a stationary ground level servicing position. Such a servicing position is illustrated in  FIG. 1 . The servicing position significantly reduces the hazard associated with climbing on-board a vehicle to service the equipment. In the servicing position, the equipment to be maintained is isolated from the vehicle and/or moved outside the confines of the vehicle, making it possible to service the equipment at ground level and/or free of encumbrances to access. As described herein, the phrase “fire-suppression equipment” refers to equipment primarily used for detecting, monitoring, and fighting a fire, or in conducting rescue operations. 
         [0014]    Lift assembly  120  is integrated into frame  104  and enclosure  108  of vehicle  100 . In the exemplary embodiment, lift assembly  120  incorporates an outer steel channel  122  and inner steel tube  124  positioned along each side of vehicle  100 . Each of outer steel channel  122  and an inner steel tube  124  are lined with, for example, a relatively high density and ultra high molecular weight polypropylene to reduce frictional forces between outer steel channel  122  and an inner steel tube  124  during operation. The lined surfaces of outer channel  122  and inner tube  124  are in contact with each other throughout the operation of the lift and provide a low friction surface without additional moving parts, such as bearings or rollers. Inner tube  124  travels a distance of approximately 36 inches (914.4 mm) along the two tracks formed by outer steel channel  122  and an inner steel tube  124 , utilizing a drive unit  126 . In the exemplary embodiment, drive unit  126  includes a single hydraulic ram including a cylinder and a piston that is hydraulically and/or pneumatically actuated. In an alternative embodiment, drive unit  126  includes a lead screw assembly. Lift assembly  120  is powered by a 12 volt DC hydraulic pump  128  and is operated by a bi-directional toggle switch  130  to raise or lower lift assembly  120 . Tank  111  is permanently mounted to a lift platform  132  for operational efficiency. Tank  111  is lowered to a servicing position at ground level for servicing and raised to an operational position on-board vehicle  100 . In the operational position, a locking mechanism  134  substantially prevents ram  126  from moving. Locking mechanism  134  is interlocked with an electrical system (not shown) on-board vehicle  100  and may be engaged manually or automatically. The locking mechanism  134  engages when the lift assembly  120  is in the fully retracted position, and operates to prevent lift assembly  120  from being lowered in the event that a rear enclosure door  136  is not fully open or the vehicle is not secure such that movement of the vehicle is substantially blocked. 
         [0015]      FIG. 2  is a rear schematic view of vehicle  100  (shown in  FIG. 1 ). Lift assembly  120  is illustrated in the operational position wherein tank  111  is fully housed in enclosure  108  such that door  136  may be closed by rolling door  136  down from its open position in direction  200 . 
         [0016]      FIG. 3  is a side schematic view of an alternative exemplary embodiment of vehicle  100 . In an alternative embodiment, lift assembly  120  is oriented parallel to the ground (horizontal). Accordingly, lift assembly  120  is operable in both an inclined configuration (shown in  FIG. 1 ) and a configuration that is parallel to the ground (shown in  FIG. 3 ). 
         [0017]    During operation of vehicle  100 , tank  111  is housed in enclosure  108  with door  136  extended in a closed position, for example, during travel to the location of a fire or other emergency. After arrival at the emergency location, door  136  may be retracted to an open position exposing limited access to tank  111  to support operation of a fire suppression activity, for example. Such limited access may be desirable for monitoring tank  111  or operating valves and switches coupled to tank  111 . 
         [0018]    During servicing, with vehicle  100  secured or being disabled for movement, tank  111  is extended horizontally from the confines of enclosure  108  using lift assembly  120 . Lift assembly  120  is interlocked using switches coupled to 12 volt DC hydraulic pump  128  and toggle switch  130  to prevent operation of lift assembly  120  if door  136  is not fully retracted in the open position or if vehicle  100  is not fully secure. Additional interlocks may be employed depending on the particular configuration of vehicle  100  and the equipment. Tank  111  is extended by operating switch  130 , which aligns hydraulic valves to supply fluid to an extend side of ram  126 . Lift assembly  120  may be configured to be stopped in an intermediate position between fully retracted and fully extended positions. When the lift assembly is fully retracted, it may be locked in position using locking mechanism  134 . 
         [0019]      FIG. 4  is a rear schematic view of another embodiment of vehicle  100  (shown in  FIG. 1 ). In the exemplary embodiment, lift assembly  120  is configured to extend a piece of equipment, such as pump  400  from within enclosure  108  at a side  402  of vehicle  100  to an accessible position substantially outside the perimeter of enclosure  108  and/or vehicle  100 . In an alternative embodiment, lift assembly  120  is configured to raise and lower pump  400  from a position within enclosure  108  to a position proximate ground level similar to the embodiment illustrated in  FIG. 1 . 
         [0020]    The above-described means for removing the hazards associated with servicing such equipment as fire suppression systems at elevation is a cost-effective and highly reliable system. The various embodiments of the present invention allows, for example, the fire suppression system to be relocated at ground level or in a position such that it is no longer necessary for personnel to either climb onto a vehicle or work in an isolated space. Accordingly, the lift system facilitates operation of for example, fire-fighting or rescue equipment in a cost-effective and reliable manner. 
         [0021]    While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.