[Background Art] Elevators and escalators are used for mass-transportation of large number of passengers in the buildings like department stores, subways, airports, cinemas, stadiums or others in which many people move.

The elevator, which vertically moves single cage up and down, is usually used for higher buildings of over 5 stories. The elevator travels relatively fast but its accommodation is limited and passengers have to wait for a while for the cage to come back as the cage stops and moves floor to floor. Therefore, the elevator is not suitable to transport large number of passengers between lower floors of a building.

The escalator is a transportation system of a caterpilla-like

staircase continuously moving on the slant so that passengers get on and off anytime as it moves. For this difference from the elevator, it is usually used for lower floors of the buildings.

As the escalator, however, moves much slower than the elevators, its transportation efficiency is low. On top of that, the escalator is not so economic because it occupies large space and consumes much electricity.

Besides the economic aspects in installation and operation, the elevator has some safety problems; for instance, if a passenger falls down for slips or sudden stop, following passengers are likely to fall down which may cause serious casualties. It happens sometimes that a passenger crushes his head into the wall when he absent-mindedly pull his head out over the guard rail. It also occurs sometimes that the passengers'dress or other belongings are stuck at the chink between the elevator's guard rail and steps.

Meantime, the escalator has separate upward and downward steps.

Therefore, the passenger cannot go back on the moving steps and he has to trouble to walk around to the other side of the escalator to go back.

Therefore, it is an object of the present invention to provide a

totally new lifting system faster with higher transportation efficiency per unit area than the escalators It is another object of the invention to provide an economic lifting system for its lower cost for installation, operation and maintenance.

It is still another object of the invention to provide a lifting system safer and more convenient.

[Disclosure of Invention] In order to satisfy the objects of the invention, the present invention comprises a pair of multi-cage lifts each having a multiplicity of cages in a vertical direction where passengers go on board, a driving system which sets the pair of the lifts parallel to move in a seesaw way where one lift moves up while the other moves down and vice versa and to stop the pair of lifts in the way where the cages of both lifts except the top cage of one lift and the bottom cage of the other lift, face each other, and a door operating means to control the entrances and transferring doors of each cage when the lifts stop.

A preferred embodiment of the seesaw-like moving lifts in pair according to this invention is described in detail referring to the drawings.

[Brief Description of Drawings]

Fig. 1 is a cross sectional view showing outlined system of the present invention Fig. 2 is a transectional view of the present invention showing arrangement of the entrance and transferring door.

Fig. 3 is a sectional view illustrating a part of the driving system of the present invention.

Fig. 4a illustrates a floor height adjuster of the present invention.

Fig. 4b shows how the floor height adjuster works Fig. 5 shows the operation of the multi-cage lifts in pair according to the present invention.

Fig. 6 is the invention having another embodiment of the driving system with practical description of the passengers.

Fig. 7 is a transectional view of an embodiment of the present invention with the lifts in the shape of octagon.

Fig. 8 is a transectional view of an embodiment of the present invention with the lifts in the shape of circle.

[Best Mode for Carring Out the Invention] Fig. 1 shows seesaw-like moving lifts for 4-floored building comprising a pair of multi-cage lifts having 3 cages (10,10'), driving system (20) to move both lifts to reverse directions as seesaw moves, a floor-height adjuster (30,30') to adjust height of the cage

of the multi-cage lifts (10,10') to the height of the floor, and buffer (40,40') for buffering the load of the descending lifts (10, 10t).

Each multi-cage lift (10,10') has 3 cages (11,11') in a column. As shown in Fig. 2, the multi-cage lifts (10,10') have entrances (12a, 12b, 12c) at the three walls for passengers to enter the each cage (11, 11') at each floor and transferring door (13) for passengers to move into the neighboring cage of the other lift. Therefore, when the entrances (12a, 12b, 12c) coincide with the porch at each floor, passengers can get in or out the cages (11,11t) and simultaneously passengers can also move to the adjacent cage (11') from a cage (11) through the transferring door (13).

The entrances (12a, 12b, 12c) and the transferring door (13) are, of course, closed for safety purpose while the lifts are in motion. Usual automatic door system of an elevator can be applied.

Preferably, the number of cages of each lift is one floor less than the total number of the floors so that each lift vertically travels the distance same as the height of a floor but to the adverse direction like seesaw. Consequently, in this embodiment, two cages of each lift always duplicate when stops.

The driving system (20) is for operating the pair of lifts to move in a seesaw way comprising a rope (21) at the both ends of which two lifts (10,10') are hanged, a guiding roller (22,22') for supporting and guiding the rope (21), reversible motor (23), a chain sprocket (24) speed-reductively driven by the motor (23) to move the rope (21), a flywheel (25) to rotate coaxially to the chain sprocket (24) for enhancing the moment of rotation, a support (26) able to absorb shock, a chain (27) linked in the middle of the rope (21) to directly engage to the chain sprocket (24), and a break (28) and a break lining (29) to safely hold the rope (21) when stops.

The floor-height adjuster (30) is for adjusting the stopping position of the cage (11) when it travels floors of different height). As illustrated in the Fig. 1, upper cages (lla, 11a') which travel the second floor (2F) and the third floor (3F) of the same height are fixed to the body of the lifts (10,10') while middle cages (lie, lie') and bottom cages (12b, 12b') traveling floors of different height are adjusted by the floor-height adjuster (30) to be positioned at the right stopping point. The floor-height adjuster (30) may use a pantograph jack as shown in Fig. 4a and 4b. The follower (31) of the pantograph is linked with the bottom of the middle cages (llb, llb').

The bottom cages (lie, 11c') are linked to a tie bar (32) of the pantograph jack. A double screw (33) of the pantograph is engaged to a gear (34) which is driven by a motor (not shown) to control the

distance from the double screw (33) to the cages to adjust the stopping positions of the cages.

The buffers (40,40') such as spring are for softly stopping the lifts (10,10 by buffering the weight of the lift) when any of the lifts descends. It also works to decrease load to the motor (23) of the driving system (20) as the restoring force of the buffers (40, 40') pushes up the lift.

Fig. 1 shows auxiliary brakes (14,15) which operate to hold the pair of the multi-cage lifts on its way to stop to prevent the lifts from shaking or dropping, when the brake (28) or the brake lining (29) does not properly work,. The control circuit (50) in Fig. 1 is for sensing and controlling every part of the lifts including starting and stopping, opening and closing entrance and doors.

Fig. 5 illustrates how the multi-cage lifts in pair of the present invention works in a seesaw way. The figure at left shows the lifts at start to move and the figure at right shows the lifts at stop after moving. Driven by the motor of the driving system, each lift alternates position as shown in Fig. 5 and back to the original position again if the motor reversely works. The lifts stop after they set in the right position, and the entrances and transferring doors open for passengers to get in or out.

At the start position, the left lift (10) is down to the bottom floor (1B) while the right one (10') is up to the highest floor (3F). In this position, the upper cage (lla) and middle cage (llb) of the left lift (10) respectively face the middle cage (llb') and lower cage (llc') of the right lift (10') while the rest of the cages of both lifts (10,10') stand alone respectively at the bottom floor (1B) and the highest floor (3F).

At the stop position after moving, the left lift (10) is up to the highest floor (3F) while the right loft (10') is down to the bottom floor (1B). In this position, the middle cage (llb) and the lower cage (lie) of the left lift (10) respectively face the upper cage (lla') and the middle cage (llb') of the right lift (10') while the rest of the cages of both lifts (10,10') stand alone respective at the highest floor (3F) and the bottom floor (1B).

In the start position, passengers A and C are respectively in the upper and middle cages (lla, llb) of the left lift (10) and passenger B is in the middle cage (llb') of the right lift (10t). Then, as they move to facing cages through the open transferring doors and the lifts move again, passenger B is on the third floor and at the same time, passenger A and C respectively descend one floor below at the stop position. In this way, many passengers getting on the lift from the

different floors simultaneously move up or down to other floors.

Consequently, mass transportation of passengers at the same time is available as shown in Fig. 6.

Fig. 6 shows an embodiment using two hydraulic cylinders (70,70') instead of motor of the driving system and gives more realistic view of passengers getting in and out of the lifts. When the hydraulic cylinders (70,70') are used, buffers may not be needed.

The shape of combination of the multi-cage lifts in pair can be varied to meet the efficient application of the available space or for esthetic purpose, for instances, combination to form an octagon as shown in Fig. 7 or a circle as in Fig. 8.

As the embodiment disclosed above is for the building of 4 floors, it has a pair of lifts each having 3 cages but, of course, each lift can have 2 cages or more than 4 cages according to the number of floors of a building. It is possible that a multiple pairs of lifts can be combined depending on the number of floors of a building.

Industrial Applicability] As described above, the present invention provides a multi-cage lifts in pair each of lift having a multiple cages for transporting large number of passengers at a time by operating a pair of multi-cage lifts

in a seesaw way.

As the lifts according to the present invention vertically travels like an elevator, it transports passengers faster than an escalator and also enables many passengers to get in or out on a multiplicity of floors at a time. Therefore, it is possible to enhance the efficiency of transportation of the passengers.

As the invention requires less cost and less area to be installed than usual escalator, it is economic and maximizes the utility of building space. It also costs less for maintenance and operation. On top of that, it is safer than usual elevator as it has no danger to drop and unlike an escalator, as passengers are transported in a closed cage, they would not be injured by outside obstacles. The present invention is also convenient for passengers as they can move to other floor by walking a few steps as they work on a plane corridor.