SPECIAL ELEVATORS Reporter: ESMUNDO, ANNA BETH BSCE 2-2 A. Unique Transaction Design 1. Sky Lobby Elevator System - involves transporting large group of people from the street lobby to the upper lobby of sky plaza where passenger will be transferred to another elevator to continue their upward journey. 2. Double Deck Elevators -an elevator with two cabs attached together, one on top of the other. This allows passengers on two consecutive floors to be able to use the elevator simultaneously 3. Observation Car Elevators - creates places of character and destination where people can meet. 4. Slant Elevators -Unlike a standard elevator, it can go up tilted grades, and can be used for both residential and commercial purposes. The purpose of inclined elevators is to provide accessibility to steep hillsides and inclines at minimal effort to the user. Inclined elevator is a form of cable railway. 5. Rack and Pinion Elevators - operate differently as there are no hoist ropes or cables. The drive motor is attached to the top of the car and the drive gear, called a pinion, is attached to the motor. This allowed for there to be a permanently mounted gear track, creating a no slip elevator system for use in harsh environments, like on an outdoor construction site. B. Hydraulic Elevators -are elevators which are powered by a piston that travels inside a cylinder. An electric motor pumps hydraulic oil into the cylinder to move the piston. The piston smoothly lifts the elevator cab. Electrical valves control the release of the oil for a gentle descent. -The principle of hydraulics is based on Pascal’s law of the incompressibility of fluids: any change in pressure applied at any point in the fluid is transmitted undiminished throughout. This pressurized fluid is used for the generation, control, and transmission of power. -Benefits of Hydraulic Elevators • No need for reinforcement. The cylinder that lifts the elevator cab is supported by the ground underneath (for holed hydraulic only). • Are usually cheaper than traction units. • If the line breaks, the elevator will fall no faster than oil can escape. C. Residential Elevators and Chair Lifts Of the two designs, the stairlift is more evident because there is no way to conceal it, although some do fold up when not in use. The stairlift may have a seat or platform, and some may also have safety bars or straps Elevators that use a shaft can be concealed from view with different styles of panels or doors on the exterior. The inside also has a variety of style choices. Elevators that do not use a shaft, such as pneumatic elevators, are meant to be in the open. Elevators do add resale value to the home, particularly if they were built into the home at the time of initial construction. Other factors also contribute to the resale value such as if they are concealed from view and have a cab and shaft that are designed to match the rest of the home. Reports vary, but most agree that adding an elevator increases the total value of your home by around 10%, which can give you a 60% to 100% return on investment for the elevator depending on the cost of the project and the current value of your home. Stairlifts do not add value to the home because they may not be needed by the future occupants, although they can be easily removed. FREIGHT ELEVATORS A. FREIGHT CAR CAPACITY -Capacities corresponding to a specific platform size are due to the varying square-foot loads that are permissible. This is taken into account by the American Society of Mechanical Engineers (ASME) Standard A17.1, which has established five load classifications for freight elevators: Class A. General Freight Loading by hand truck.Single items may not exceed 25% of the carrated load. - The rated load is based on 50 pounds per square foot (psf) (244 kg/m2) of net inside platform area.Class B. Motor Vehicle Loading. The elevator car will carry automobiles or automobile trucks. The rating is based on a load of 30 psf (146 kg/m2) of net inside platform area. Class C1. Industrial truck loading; truck carried. Class C2. Industrial truck loading; truck not carried.Cla ss C3. Concentrated loading; no truck used; increments greater than 25% of rated capacity. For classes C1, C2, and C3 the rated load is based on 50 psf (244 kg/m2). Cars have automatic leveling. B. FREIGHT ELEVATOR DESCRIPTION -As speeds are generally between 50 and 200 fpm (0.25 to 1.0 m/s), a geared-type traction machine or a hydraulic unit is used. The preferred system of control is collective, with a variable-voltage, dc supply, either unit multivoltage (UMV) or variable-voltage, variable-frequency (VVVF). If the car is used infrequently (fewer than five trips a day), economy is very important, accurate leveling is not essential, and a rougher ride is tolerable, then a two-speed acrheostatic control may be used. -General-purpose freight elevators, whether traction or hydraulic, in load ranges of up to 20,000 lb (9072 kg), are standard design items applicable to all types of commercial and industrial buildings. -This item is of great importance in larger car installations, because traction unit rails must be supported every few feet and additional steel provided to accomplish this. C. FREIGHT ELEVATOR CARS, GATES, AND DOORS -Cars for freight service are normally built of heavy gauge steel with a multilayer wooden floor, the entire unit being designed for hard service. Guarded ceiling light fixtures are required. Car gates slide vertically and are a minimum of 6 ft (1.8 m) high. -Hoistway doors are normally vertical lift, center opening, manual or power-operated. Both car gateand hoistway doors are counterweighted and open fully to give complete floor and head clearance. D. FREIGHT ELEVATOR COST DATA -The cost of a freight elevator installation, as with passenger elevator installation, is dependent upon many factors, principally capacity, type of control, use, and type of door operation. Exact pricing, like specific selection, is outside the scope of this discussion. A reputable manufacturer or elevator consultant should be sought for such information. Some general remarks on pricing, however, follow: 1. Variable-voltage-controlled equipment, depending on the type, costs 20% to 50% more than rheostatically controlled equipment. 2. Above a basic two-floor rise, the cost increases linearly with rise. 3. Electric door operation can increase the cost of a car installation 10% to 25%.
