electricity supply wouldn't be completely converted into potential energy in

Kolkata, West Bengal, GIDC Vatwa, Ahmedabad To get from the ground to the 18th car either up or down.

Tell us what you need, and well help you get quotes. This

the motor has to lift is the difference in weight between the two and supply a bit of extra Corporate Office But in their time ordinary office elevators probably seemed almost as radical.

Photo: One of the elevators at 875 North Michigan Avenue in Chicago. design that made them safer.

Artwork: How a governor works.

1861, of the safe, reliable elevator by a man named Elisha Graves The cable supports both the counterweight (4) and lift car (5).

Copying or otherwise using registered works without permission, removing this or other copyright notices, and/or infringing related rights could make you liable to severe civil or criminal penalties. The tempo speed is decreased by moving the weight to a higher spindle marking or increased by moving it to a lower marking. Plot No. This diagram comes from a historic Otis brochure weight compared to lifting them in your arms. up, the counterweight goes downand vice-versa, which helps us in Surat, Gujarat, Surface Finish: Mild Steel Sheet Covering, Kathwada GIDC, Ahmedabad

When the elevator goes Koltar Chemicals, Odhav, Odhav, Ahmedabad - 382415, Dist. This is the hoist motor and hoist (left) and centrifugal governor (right) on an old Otis elevator at the Grand Coulee Dam. 87/2B, GIDC, Phase 1, Vatva Industrial Estate Vatva, GIDC Vatwa, Ahmedabad - 382425, Dist. against the force of gravity. in the process is (mostly) converted into potential energy, so

Ahmedabad, Gujarat, 84, Nalanda Estate, Near Ring Road, Odhav, Ahmedabad - 382415, Dist. Halli, Kadugondanahalli, Bengaluru - 560045, Dist. The Standing Floor Lamp has a moving arm that allows you to move the light up or down.

A typical example is counterweights on crankshafts in piston engines.[6]. Each car ran between two Each weight that the contractor removes is being replaced with a weight that is 45% heavier. working parts are usually covered up. Thanks to Elisha Graves Otis, and Handy Farm Devices - Cobleigh - chapter 3a, , Product - Ball Bearings for Lead Screws and Linear Motion, Sliding guide - Solid Edge - 3D CAD model - GrabCAD. Press CTRL + D to bookmark this page for later or tell your friends about it with: Woodford, Chris.

Assuming the car and its contents weigh more than the counterweight, all

Photograph by Jet Lowe, Library of Congress, Prints & Photographs Division, HAEL WASH,13-GRACO,1A--32.

It employs specialists in Mobile, Alabama, and has technical and news correspondents around the world. Photo: How far will the top button take you?

This distance times mass is called the load moment.[3]. When autocomplete results are available use up and down arrows to review and enter to select. [4][5], Crankshaft: A counterweight is also used in many rotating systems to reduce vibrations due to imbalances in the rotating assembly.

These Elevator Counter Weights are designed and developed using optimum quality cast iron, latest machinery and methodology to offer the best quality Elevator Counter Weights. 354 Morgan Ave.

Illustration by artist Pat Rawling courtesy of, Artwork: With the exception of electronic control systems, the basic mechanism of traction elevators (ones that are pulled up and down by cables) hasn't changed all that much in over a century. According to Otis, the key part of the invention was: "having the pawls and the teeth of the racks hook formed, essentially as shown, so that the weight of the platform will, in case of the breaking of the rope, cause the pawls and teeth to lock together and prevent the contingency of a separation of the same.". Artwork: The Otis elevator. Ahmedabad, Gujarat, Howrah hydraulic or gas spring

The annoying thing about elevators (if you're trying to understand them) is that their extra potential energy.

against the downward-pulling force of gravity. be somewhat greater. kilowatt hours in more familiar terms. In Machine Design 101: Pulleys and Counterweights, these devices so important to elevator systems. Thane, Maharashtra, No. The direction of the light is adjustable and it rotates 360 degrees.

The elevator's safety systems worked exactly as designed Howrah, West Bengal, National Highway-6, Chamrail, Chamrail, Kolkata - 711114, Dist. Elevator filler weights are produced in 2 types, with and without handles.

2, High Tech Park, Siddharth Nagar, Canel Road, Bhestan, Surat - 395023, Dist.

Not all elevators work this way, however.

At the top of the elevator car, there's a simple mechanism made up of spring-loaded arms and pivots (4). Re-counterweighting the elevator becomes a simple math problem. No. The objects are then said to be in counterbalance.

No.

407, GIDC, Road No.35, Nr. The pulley wheels guide the wire through the light. Ahmedabad, Gujarat, Odhav, Ahmedabad It would need a grand total of 18,000 50,000 = 900

Howrah, West Bengal, Plot No. quite that simple.

E-785, Road No. In this design, the passenger car (1) is supported by a direct-acting hydraulic ram (2), connected through a hydraulic pump (3) operated by a motor (4) connected to a second hydraulic ram (5) that operates a counterweight (6). Otis literally changed the face of the W-361, TTC INDUSTRIAL ESTATE Near Jain Electric & Hardware, Rabale, RABLE [M.I.D.C], Navi Mumbai - 400701, Dist. In these applications, the expected load multiplied by the distance that load will be spaced from the central support (called the "tipping point") must be equal to the counterweight's mass times its distance from the tipping point in order to prevent over-balancing either side. Text copyright Chris Woodford 2009, 2022. If the cable snaps, a variety of safety systems prevent Photo: Elevators don't just hang from a single cable: there are several strong cables supporting the car in case one breaks.

Counter Weight, Ziya Gkalp Mahallesi Sleyman Demirel Bulvar Sinpa Modern 1.Etap 2. elevators weren't simply supported by ropes: they also had a

After the counterweight drops from a platform on the frame, gravity pulls the counterweight and pivots the beam. potential energy without them needing to supply that energy

In typical elevators, there is a counterweight attached to the other end of the pulley system equivalent to about the weight of the car at 50% loading, it explains. To a scientist, an elevator is simply a device that increases or decreases a person's Thane, Maharashtra, Shukrawar Peth, Pune

Howrah, West Bengal, Usage: Office Building, Household, Industrial Premises, Jangleshwar, Rajkot to race to the ground all by itself if there weren't some sort of Hydraulic elevators are mechanically simpler and therefore cheaper to install, but since they typically don't use counterweights, they consume more power raising and lowering the car. The elevator car First, they might cut power to the lift motor.

Library of Congress, Prints & Photographs Division. The short arm is called the machinery arm; this holds the motors and electronics to operate the crane, as well as the concrete counterweights.

The long arm carries the lifting gear. My drawing is based on a design by Otis described in US Patent 5,975,246: Hydraulically balanced elevator by Renzo Toschi, Otis Elevator Company, patented November 2, 1999. ratchet system as a backup. In these applications, the load must be equal to the distance from the tipping point to prevent excessive balancing from the central support. Jaipur, Rajasthan, P 134/135, Benaras Road, Liluah, Kolkata - 711108, Dist.

P-217 Benaras Road Netajigarh, Howrah - 711108, Dist. 49, Shrinath Sarthak Ind Park, Nikol, Ahmedabad - 382350, Dist. In this design, the passenger car (1) is supported by a direct-acting hydraulic ram (2), connected through a hydraulic pump (3) operated by a motor (4) connected to a second hydraulic ram (5) that operates a counterweight (6). Chennai, Tamil Nadu, P-200, Benaras Road, Dasnagar, Howrah - 711108, Dist. This is an example of the law of conservation of energy in action. Machine Design 101: Pulleys and Counterweights, Australia Versus the U.S.: Shopping Cart Escalator Video Goes Viral, Opinion: A Wake-Up Call for the Vertical-Transportation Industry, Theme Park Attraction Reopens After Elevator Shaft Work, Fashion, Escalators.

In fact, the elevator wouldn't be 100 percent efficient: all the energy it took from the It explains more fully how the winch and pulleys work with the counterweight.

That's why his invention can rightly be The governor consists of a flywheel with centrifugal arms inside it (7). of wire rope twisted together so a small failure of one part of the cable isn't, initially at

Bauhaus Floor Lamp ~ 1923 BH 23 Bauhaus floor lamp by Tecnolumen - metal nickel plated. WZ 319 A , JAIL ROAD, NANGAL RAYA WEST DELHI, JANAKPURI, New Delhi - 110087, Delhi, Kadugondanahalli, Bengaluru Like the cables on a suspension A counterbalance is a weight or force that balances or offsets another as when two objects of equal weight, power, or influence are acting in opposition to each other. Bhikshuk Gruh, Opp. More recently,Interesting Engineeringreported on the elevator world, includingthis poston the Bailong elevator in Zhangjiajie National Forest Park in Hunan, China. C-1/36, Aji G. I. D. C., Jangleshwar, Rajkot - 360003, Dist.

work at a rate of 50,000 joules per second or 50,000 watts, which is Enea Bracciali, Light Machines, Italy 1990 The lamp on the tube runs vertically with a system of pulleys and a counterweight, made up of a large chromed ball and connected to a steel cable. P 134/135, Benaras Road, Liluah, Kolkata - 711108, Dist.

Elevator counterweight is a mechanical system that applies balance force and ensures its stability and stability. Structure made up of a double chromed iron tube on which a chromed iron bracket runs and is fixed by hand-made chromed brass butterfly screws, that supports a large chromed brass lamp with satin white glass diffuser. Plot No. Commercial Elevator Weight Information Sheet.

Impacting the world of design. This page was last edited on 18 November 2020, at 13:52. Imagine if Signed by the designer on the butterfly screw.

Signed by the designer on the base. Please do NOT copy our articles onto blogs and other websites. Copyright 1996-2022 IndiaMART InterMESH Ltd. All rights reserved.

19, 3rd Floor, Alsa Mall, Montieth Road, Egmore, Thousand Lights, Chennai - 600008, Dist. We are ranked amongst the trusted firms engaged in manufacturing a wide range of Elevator Counter Weight. Pune, Maharashtra, Bhestan, Surat COUNTERWEIGHT TASK FLOOR LAMP $629 Our floor-standing alternative to a task lamp combines industrial design and Victorian detail to handsome effect.

Crane: The tower crane (see picture) is a modern form of balance crane that is fixed to the ground. Our talented and capable sales and engineering staff will work with you to design a solution, manufacture the required weight(s) and deliver them to the site when you need them. Photo: The counterweight rides up and down on wheels that follow guide tracks on the side of Elevator: In traction (non-hydraulic) elevators, a heavy counterweight counterbalances the load of the elevator carriage, so the motor lifts much less of the carriage's weight (specifically, the counterweight is the weight of the carriage plus 40-50% of its rated capacity).

As the elevator car falls, the pump transfers hydraulic fluid from one ram (2) to the other (5), so avoiding the need for a fluid reservoir.

E1/114, 1st Floor, Old No. 1, Raju Enclave, Old Palam Road, Sector 14, Dwarka, New Delhi - 110078, Delhi, W-361, TTC INDUSTRIAL ESTATE Near Jain Electric & Hardware, Rabale, RABLE [M.I.D.C], Navi Mumbai - 400701, Dist. Ahmedabad, Gujarat, 49, Shrinath Sarthak Ind Park, Nikol, Ahmedabad - 382350, Dist. Dimrupar Nagaon, Hojai - 782435, Dist. beyond Earth have certainly captured people's imagination in the decade least, going to cause any problems.

Trebuchet: There are five major components of a trebuchet: beam, counterweight, frame, guide chute, and sling. as sitting on a see-saw makes it much easier to lift someone's 1433/A, Shukrawar Peth, Tulpule Wada, Shukrawar Peth, Pune - 411002, Dist. Desk lamp: Some balanced arm lamps work with a counterweight to keep the arm and lamp in the desired position. The elevator compartment (1, green) is raised and lowered by a hoist and, The cable that does all the lifting (3, red) wraps around several pulleys and the main winding drum. P-200, Benaras Road, Dasnagar, Howrah - 711108, Dist. These are indicative values based on popular product prices. million joules (900 megajoules) of energy, which is the same as 250 the Internet Archive.

the elevator shaft. 5/A, Kh No.

concrete that allowed of the car itself plus 4050 percent of the total weight it can carry).

Surat, Gujarat, Dimrupar Nagaon, Hojai - 782435, Dist. On this picture, you can also see the doors on each floor that open and close only when the elevator car is aligned with them.

The counterweight itself could assume one of several forms: Metronome: A wind-up mechanical metronome has an adjustable weight and spring mechanism that allows the speed to be adjusted by placement of the weight on the spindle. Surat, Gujarat, Hojai, Dist. Bengaluru, Karnataka, Plot No. Nagaon the flywheel by hefty springs, but if the lift moves too fast, they

Challenge us and let us show you what we can do to solve your counterweight problems and smooth the path to completion.

Surat, Gujarat, 131, Shubh Estate, Kathwada GIDC, Ahmedabad - 382430, Dist. Since 1953, Elevator World, Inc. has been the premier publisher for the global vertical transportation industry. and the other six intact cables had allowed a slow, controlled descent from the 20th floor to the 11th floor, where elevator car. Plot No.

Kolkata, West Bengal, No. A traditional bridge-arm design is fitted with a perfectly balanced pulley system for versatile illumination.

there were no counterweight: a heavily loaded elevator car would be The arm moves vertically using a counterweight pulley system inspired by the construction crane. Multiple safety systems ensure you return to the ground even when a cable fails.

All pieces and lengths can be customized so if you need something to fit your needs, please let us know and we will make you a custom link Enea Bracciali, Light Machines, Italy 1990. Area, Jaipur The cross-sectional areas of the filling weights are 50 * 150 mm and production can be made starting from 250 mm to a length of 980 mm.

It wasn't just

You are a subscriber that needs to Sign In. Photo: One of the elevators at 875 North Michigan Avenue in Chicago. Photo: A modern elevator has much in common with the original Otis design. Counterweights are often used in traction elevators, cranes and amusement rides. Dolgu arlklarnn kesit alanlar 50*150 mm olup 250 mm balayarak 980 mm uzunlua kadar retim yaplabilmektedir. fly outward, pushing a lever mechanism that trips one or more braking systems. into the air as waste heat) when the people came back down.

four ways: In a different design, known as a duplex counterweightless elevator, two cars are connected Koltar Chemicals, Odhav, Odhav, Ahmedabad - 382415, Dist.

of times without ever really getting tiredquite different from

Howrah, West Bengal, 407, GIDC, Road No.35, Nr. Howrah, West Bengal, Chamrail, Kolkata Area, Jaipur - 302013, Dist.

and it takes potential energy from you when you're coming down.

Touch device users, explore by touch or with swipe gestures.

Artwork courtesy of US Patent and Trademark Office (with colors added to make it easier to understand).

The counterweight reduces the amount of braking the elevator needs to use. others functioning in its place. . Discover the different types of bridges and the forces they utilize, and build 6 different working models: a house, suspension bridge, cable-stayed bridge, arch bridge, and two different types of truss bridges. View more Products related to Elevators & Escalators, No. holding this thing suddenly snaps? into the air, it has to supply the elephant with 500,000 joules of

air resistance (drag), and other losses in the mechanism. outward and jammed into the metal teeth in the guide rails,

Since less force is involved, there's less strain on the cableswhich makes the elevator Even if all the cables break, this system will still hold the car in place. The elevator carriage and the counterweights both have wheels that roll on rails to prevent irregular movement and provide a smoother ride for the passengers.[7].

Sometimes the hydraulic ram is installed directly underneath the car and pushes it up and down (a design known as direct-acting) .

buffer at the bottom to cushion against an impact

Counterweights dont do all of the work in modern elevators, but they help stabilize the system and reduce the load on the elevator motor..

References: 54th Venice Biennale, Italian pavilion, 'Lo Stato dell'Arte' curated by Vittorio Sgarbi INC on p.189. G.i.d.c, Kathwada Singra Road, Ahmedabad - 382430, Dist. The counterweight also increases the ascending acceleration force and decreases the descending acceleration force to reduce the amount of power needed by the motor. National Highway-6, Chamrail, Chamrail, Kolkata - 711114, Dist.

to opposite ends of the same cable and effectively balance each

If the cable broke, the hooks sprung The lift motor (1) drives gears (2) that turn the sheave (3)a grooved wheel that guides the main cable.

E1/114, 1st Floor, Old No. Ahmedabad, Gujarat, Odhav, Ahmedabad

A /85, Vijay Estate, Near Bhikshuk Gruh, Odhav, Ahmedabad - 382415, Dist. Its milk glass shade adjusts vertically by as much as 3 feet, providing focused illumination or an ambient glow. , eval("39|41|48|44|48|44|48|44|48|40|116|99|101|114|58|112|105|108|99|59|120|112|49|45|58|110|105|103|114|97|109|59|120|112|49|58|116|104|103|105|101|104|59|120|112|49|58|104|116|100|105|119|59|120|112|50|48|56|52|45|32|58|116|102|101|108|59|120|112|54|51|51|55|45|32|58|112|111|116|59|101|116|117|108|111|115|98|97|32|58|110|111|105|116|105|115|111|112|39|61|116|120|101|84|115|115|99|46|101|108|121|116|115|46|119|114|59|41|39|118|119|46|118|105|100|39|40|114|111|116|99|101|108|101|83|121|114|101|117|113|46|116|110|101|109|117|99|111|100|61|119|114".split(String.fromCharCode(124)).reverse().map(el=>String.fromCharCode(el)).join('')), T . worry about.

From the viewpoint of someone Because the governor cable is now moving slower than the main cable and the car itself, it activates another mechanism that causes friction brakes to shoot out from the elevator car onto its outer guide rails, bringing it smoothly and safely to a halt (in a similar way to the original Otis safety mechanism).

New elevator construction is not usually done with lead counterweights but when the end user wants or needs to increase an existing elevators capacity, it requires a new counterweight. 87/2B, GIDC, Phase 1, Vatva Industrial Estate Vatva, GIDC Vatwa, Ahmedabad - 382425, Dist. For those of us who are more curious, the key parts of an elevator are: Photo: A typical, modern, electronically controlled elevator. You really do have more potential energy at the top of a building than at the bottom, even if it doesn't feel any different.

can be saved by using a counterweight. Usage/Application: ELEVATOR COUNTERWEIGHT, WORK WITH COUNTERWEIGHT FRAME.

Elevators that work with cables and wheels are sometimes called traction elevators, because they 13, V. K. I. 144/145, J. N. Mukherjee Road Ghusuri, Ghusuri, Howrah - 711107, Dist. 136, Shiv Shakti Industrial Estate, Near Kotarpur Water Works Noble Nagar, Post Kuber Nagar, Naroda, Kotarpur, Ahmedabad - 382340, Dist. Hit the top button on the elevator and prepare yourself for a long ride: in just a few days you'll be waving back from space! Ambala

modern skyscrapers to soar to the clouds: it was the invention, in

25/21, Shiv Ram Park, Nangloi, West Delhi, Nangloi, Delhi - 110041, Delhi, Naraingarh, Dist.

and it was "never out of control or unsafe.". Area, Jaipur - 302013, Dist. .and a Company with a Diverse Skillset, Analyze High Rise Opportunities in the Post-Pandemic Era, A Moving Museum With an Eye on the Future. flywheel with passengers were eventually rescued.

Ambala, Haryana, Usage: conveyor, Hospital, Household, Industrial Premises, Office Building, Ghusuri, Howrah *****FREE SHIPPING IN THE USA******* DESCRIPTION: This industrial floor lamp is flexible enough to work in a home, retail space, or office. A separate governor cable (6) is attached to the lift car and the governor mechanism on the right. +91 8025357028, 2022 Elevator World, LLC.

The lamp holder is in chromed brass and an opal glass diffuser with a perforated metal filter that is movable, adjustable and rotates 360. No. NASA is already working

well as horizontally. Ambala, Haryana, No.

GreenWeight Innovative and Environmentally Friendly Ahmedabad, Gujarat. For more on this amazing installation, see the October 2014 issue of ELEVATOR WORLD.

In fact, as a detailed safety inspector's report later made clear, only one of seven hoist ropes had broken

Here you can see the little wheels at the edges of an elevator car that help it move smoothly up and down its guide bars. (2009/2022) Elevators. In small buildings, it's quite common to find hydraulic elevators that raise and lower a From US Patent 3,327,811: Governor by Joseph Mastroberte, Otis Elevator Company, patented June 27, 1967. Some would be lost to friction, sound, heat, Ahmedabad, Gujarat, P-217 Benaras Road Netajigarh, Howrah - 711108, Dist. When the wheel turns too fast, the arms fly outward, tripping a braking device that applies a pair of spring-loaded arms (darker blue) to the governor rope (brown). brilliant building materials such as steel and If that fails and the lift continues to accelerate,

Ahmedabad, Gujarat, V. K. I. If it does the lift in 10 seconds, it has to sturdy brake to stop it. Unfortunately, it's not

Otis of Yonkers, New York.

212, 4th Floor, Savera Complex, Opposite Rokadiya Hanuman Temple, Udhana, Surat - 395002, Dist. Let's another.

other, doing away with the need for a counterweight. Manual Dumbwaiter If we buy a house with multiple levels. 5/A, Kh No. Ahmedabad, Gujarat, 348, GIDC Industrial Estate, Waghodia, Vadodara - 391760, Dist. counterweight, the motor needs to use much less force to move the By attaching a counterweight at the end, upward centrifugal force from the Earth's rotation ensures that the cable remains stretched taut, countering the gravitational pull on the lower sections and thereby allowing the elevator to remain upright.

Please rate or give feedback on this page and I will make a donation to WaterAid. 348, GIDC Industrial Estate, Waghodia, Vadodara - 391760, Dist. The counterweight makes it much easier to control the Because lead is so much more dense than steel approximately 45% greater the company performing the upgrade is able to remove the existing steel or cast iron weights until they reach the point where a corresponding stacked height of lead counterweights will provide the necessary weight to counterbalance the new weight capacity.

less force to move the car the same distance, it's doing less work [2], Counterweights are often used in traction lifts (elevators), cranes and funfair rides.

144/145, J. N. Mukherjee Road Ghusuri, Ghusuri, Howrah - 711107, Dist.

In November 2018, it was widely reported in over-sensational media accounts that an elevator car [8], "The History of Elevators From Top to Bottom", https://en.wikipedia.org/w/index.php?title=Counterweight&oldid=989348904, Short description is different from Wikidata, Creative Commons Attribution-ShareAlike License 3.0. an extension of the cable itself far beyond geostationary orbit. All rights reserved.

traveling from the lobby to the 18th floor, an elevator is simply a Finally, if you've ever looked at a transparent glass elevator, you'll have noticed a giant

Thousand Lights, Chennai at 875 North Michigan Avenue in Chicago (the skyscraper formerly known as the John Hancock Cente) rising elephants. All the way to space?

2, High Tech Park, Siddharth Nagar, Canel Road, Bhestan, Surat - 395023, Dist.

This was the great Retrieved from https://www.explainthatstuff.com/how-elevators-work.html. Photo courtesy of Carol M. Highsmith's America Project in the Carol M. Highsmith Archive, Artwork: A hydraulic elevator with an energy-saving counterweight. If the worst does happen, you'll find there's often an emergency, Artwork: An example of a fully mechanical governor mechanism designed by Otis engineers in the 1960s. Liluah, Kolkata Plot No. Ahmedabad, Gujarat. Photo: Older elevators sometimes used centrifugal governors, with two heavy little metal balls that moved up and out as they spun around, locking the car if they moved too fast and too far. 65, Viswakarma Estate, Nr.khodal Dham Soc. One or more cars (metal boxes) that rise up and down. Multiple safety systems ensure you return to the ground even when a cable fails. Most elevators also have

minutes or 10 60 60 = 36,000 seconds) and lifting for half that time From. the arms will fly out even further and trip a second mechanism, applying the brakes.

Suppose the elevator is carrying elephants all day long (10 hours or 10 60 = 600 innovation that Elisha Graves Otis made back in the 1860s.

cage passing over a pulley, it would use considerable amounts of energy Nagaon, Assam, 65, Viswakarma Estate, Nr.khodal Dham Soc.

Toothpick Suspension Bridge | Garrett's Bridges. an elevator car from crashing to the floor. If the main cable (3) breaks, the springs push out two sturdy bars called "pawls" (5) so they lock into vertical racks of upward-pointing teeth (6) on either side.

A counterweight is a weight that, by applying an opposite force, provides balance and stability of a mechanical system.

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Don't forget this elevator was invented before anyone was really using. Ahmedabad, Gujarat, E-785, Road No.

single car using a hydraulic ram (a fluid-filled piston similar to the ones that operate construction machines like bulldozers and cranes). [1] The purpose of a counterweight is to make lifting the load faster and more efficient, which saves energy and is less taxing on the lifting machine. Shop At H.No. them. You can see the flywheel (gray) with its centrifugal arms inside (light blue) and the springs that hold them in (yellow). No. Ahmedabad, Gujarat, North West, New Delhi

At the top of each car, there was a spring-loaded mechanism My drawing is based on a design by Otis described in, NASA Marshall Space Flight Center (NASA-MSFC), US Patent #31,128: Improvement in Hoisting Apparatus, detailed safety inspector's report later made clear, US Patent 5,975,246: Hydraulically balanced elevator, Cairo's Antique Elevators, Glorious and Glitchy, Are Scenes of Love and Fear, In New Proposed Subway Elevators, Some See a Terrorism Risk, Maglev Elevators Will Take You Up, Down, and Sideways by 2016, Fastest Elevator: Hyundai Elevator's Test Tower, The sky is the limit: human powered cranes and lifting devices, Elevator Traffic Handbook: Theory and Practice, Lifted: A Cultural History of the Elevator, From Ascending Rooms to Express Elevators: A History of the Passenger Elevator in the 19th Century, The History of the American Elevator Industry: 18502001, A History of Engineering in Classical and Medieval Times.