Levitators

A new concept for elevators in tall buildings

© 2007, Rajaram PejaverPatent Pending

Press the <Page Down> key to advancePress the <Back space> key to replay a slide

What does it do?

1. Improves elevator service in existing buildings without adding banks of elevators

2. Reduces floor space needed by elevators in new tall skyscrapers

3. Allows for unique building shapes in new architecture

Product application: Existing buildings

Examples of target buildings– Office buildings– Hotels– High rise Apartments

Typical height of building is 10–20 stories

Its not possible to add new elevator shafts to building

Levitators will increase passenger capacity threefold and reduce wait times.

Product application: New skyscrapers

More and more tall buildings are being built– China has 5 of the 10 tallest buildings– Malaysia and Taipei have one each in top 10– Canada is building new residential skyscrapers

More than 30% of floor space in skyscrapers is consumed by elevators!

Taipei 101 in Hong Kong has more than 57 elevator shafts!!

Levitators will reduce the number of elevator shafts and increase its utilization

Taipei 101

Today’s technology

Limited to one elevator car per shaft

Based on counterweights

A solution: multiple cars per shaft!

The Thyssen Twin is an example of such a system.

But cars are limited to the upper or lower portion of a shaft.

But, what if the lower car needs to go all the way to the top?

Two elevator cabs, one moving down and the other moving up, share the left shaft.

Lower cab shifts to the adjoining shaft and carries on.

The system in operation

Rule: # of cars going up equals # of cars going down

1

3

6 7

2

5

4

Car 1 needs to go all the way down

Car 6 needs to go all the way up

Cars 1 & 5 are moving down

Cars 6 & 7 are moving up

Cars 1 & 2 are moving down

Cars 6 & 4 are moving up

Cars 1 & 2 are moving down

Cars 6 & 5 are moving up

Cars 1 & 2 are moving down

Cars 6 & 5 are moving up

Car 7 is moving left

Car 3 is moving down

Car 7 is moving up

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And see the Java based interactive simulator.

How does it all work?First, the Drive Assembly

Endless loop around two pulleys One side constantly moves up at a

steady speed and the other side moves down

A third track (middle) is stationary and acts as the guide rail for cars

Cars clamp on to the track moving in the desired direction: up, down or stationary.

Floor 1

Floor 2

Floor 19

Floor 20

Positioning of Drive Assemblies in each shaft: Front and Top views

Shaft

Drive Assembly

Clamp

Clamp

There are 4 Drive Assemblies per shaft. Car is clamped on to upward moving track. Yellow dots indicate location of clamp. There are 8 clamp points for each car.

Clamp

Car

Top View of car in a

shaft

Door

What else?Next, the Clamp Runner

Clamp runners slide horizontally. They are installed in pairs at the top and bottom of cars. A clamp is mounted at each end. The upper runner is shown in operation. The lower runner operates independently.

Clamp runners can slide right and engage

or slide left and engage

and return to the center position.

Clamp operation

Caliper

Runner

Upward moving Drive Track

Fluid

Car at restCar moving up

Clamps are mounted at the ends of each runner.

Car transitions from being stationary to moving up when the clamp is engaged.

Clamp action is controlled for smooth starts.

Pad

Piston

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Car at rest

Shaft

Car

Drive Assembly

Clamp

Clamp

Car is clamped on to the stationary tracks. Note yellow dots on upper runner clamping on to the center tracks.

The stationary tracks act as guide rails to stabilize the car while it is in motion.

Note: Not drawn to scale

Stopped

Car moving downwards

Shaft

Car

Drive Assembly

Clamp

Clamp

Car is clamped on to downward moving track and is moving down.

The upper runner is unused.

Note yellow dots on downward moving tracks.

Transition: Start of upward motion

2. Lower Runner moves left over upward moving track

3. Lower runner clamps on to upward moving track

4. Upper runner releases stationary track

5. Car starts to move upwards

Stopped

1. Car is stopped. Upper runner is clamped to the stationary tracks. Lower runner is not being used.

Transition: Coming to a halt

2. Upper runner clamps on to stationary tracks

3. Lower runner releases upward moving track

4. Car comes to a halt

Stopped

1. Car is initially moving up. Lower runner is clamped to upward moving tracks. Upper runner is over the stationary tracks.

Transition: Switching Shafts

1. Clamp extends to adjoining shaft

2. Clamp locks up

3. Cab shifts

4. Clamp unlocks

5. Clamp retracts

Counterbalancing Cars

Figure 2a– 2 cars balance each

other on same drive Figure 2b

– 2 cars balance each other on different drives

– Shafts are mechanically linked

Figure 2c– 4 cars balance each

other on different drives Figure 2c

Figure 2a

Figure 2b

Multiple Drive Zones

Problem: Drive assembly limitation– A single span of drive assembly is not

suitable for tall buildings.

Solution: Stacked drive segments – Allows for shorter drive segments– Optional: express & local speeds

Details: Car switches drives– Both segments serve the same shaft– Segments are mechanically linked– No horizontal car motion

Transition Zone

Slanted & Curved shafts

Car AMoving up

Clamp Runner

Clamp Runner

Clamp Runner

Clamp Runner

Car BStopped

and alignedwith door

Clamp Runner

Clamp Runner

Ele

vato

r d

oorw

ay in

lan

ding

Clamp Runner

Clamp Runner

Future extensions

Tilting cars during horizontal acceleration

– Reduces passenger discomfort

Moving horizontally between elevator banks

Personal sized elevator cars– Faster transit with fewer stops

Splicing cars together to form a larger car

Express drive zones

Key Innovations

Elevator system without counterweights Drive assembly for elevators Clamp assembly and clutch mechanism Use of extension arm in elevators to facilitate

arbitrary transfer between adjacent shafts Statistical counterweight balancing algorithm Control system for collision avoidance and car

trajectory Operation in slated & curved shafts Multiple drive zones and express zones

Main issues & obstacles

Need to rework the US Elevator Code– Shared by Canada, and now China– Europe, Mid East & India may be easier

Build a scaled prototype– Seeing is believing !

Design production model, while maintaining– current safety margins– operating efficiencies – passenger comfort

Project Timeline

Task Start Date End Date

Patent search Jan 07 July 07

Patent application July 07 July 09

Engineering design Oct 07 Dec 08

Find venture funding July 08 July 09

Assemble project team Jan 09 July 09

Develop scaled prototype July 09 Jan 11

Product development Jan 11 …

Thank You !!

What do you really think of all this?

Send feedback to rajaram@pejaver.com