The invention relates to an automatic control system by means of which the operator in the car controls the doors of the lif s.

Lifts are known as devices which raise people or things by means of cars or cages and a special motor unit. Lifts are normally provided with two sets of doors, one on the outside, i.e. at the floor, and the other on the inside, i.e. on the car.

The outer door cannot open unless it is actuated by the inner door, thus preventing many accidents.

Both the inner and outer doors normally have a horizontal sliding motion. These doors can have one single wing or two wings which move in opposite directions.

The horizontal motion of the doors creates considerable problems particularly as regards the amount of space occupied in those cases where only a restricted amount of space is available for the lift.

In many cases the vertical motion of the doors would not only solve the problem of space but could also facilitat the passage of people or of things with considerabl structural and functional advantages. However this vertical motion, particularly in automati

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systems, generally creates considerable structural and functional complications which jeopardise the advantages. The invention in question solves the problem with simple and rational means as will be illustrated hereunder. The object of the invention is a system by means of which the operator in the car automatically controls the doors in lifts generally composed of two wings sliding vertically, comprising a pair of toothed wheels connected by a horizontal chain. These wheels are each integral to another toothed wheel on each of which a vertical chain spanning the same engages. The two ends of the branches of these vertical chains spanning the two toothed wheels on the same side, are fastened to the upper wing while the two ends of the other two branches of these chains are fastened to the lower wing. Therefore when the electric motor of the car drags the horizontal chain by running in one direction, the two wings move vertically apart from one another thus bringing the door into the open position whereas when the the motor runs in an opposite direction, they move together, still vertically, one towards the other, thus bringing the door into the closed position.

Each floor is provided with an installation similar to the one already described for the door wings of the car. This installation therefore comprises a pair of toothed

wheels positioned in one end and in the other end of the space for the door at the floor, connected by a horizontal chain. These toothed wheels are each integral with another toothed wheel on which a vertical chain spanning this toothed wheel engages.

The ends of the branches of the two chains positioned on the same side on said toothed wheels are fastened to the ^■ upper wing of the two vertically sliding door wings which form the door at the floor while the ends of the other two branches of these chains are fastened to the lower wing of the door in question.

Therefore when the horizontal chain translates in one direction the two wings move vertically apart from one another thus bringing the door into an open position, whereas when the same horizontal chain moves in an opposite direction the two door wings come together, again vertically, one towards the other, bringing the door into a closed position. Connected to the horizontal chain of the car is a coupling carriage, sliding horizontally, provided with an oblong thrusting' means positioned vertically while on the horizontal chain of the installation at each floor another σarriage is connected, sliding horizontally, provided with a pair of idle rollers. The dimensions and position of the oblong thrusting means on

the carriage of the car and of the pair of rollers on the carriage of the installation at the floor are such that when the car is at a floor, the oblong thrusting means of the carriage of the car moves into position between the pair of rollers of the carriage at the floor.

Therefore the opening motion of the door of the car generated by the electric motor positioned in the same and running in one direction, will be transmitted by the thrusting means of the carriage of the car and by means of the rolle s o ^* f the carriage of the installation at the floor to the latte_r carriage, thus bringing about the simultaneous movement of the door at the floor opening and the vertical sliding of the door wings at the floor together with the door wings or ^" the car. When the carriage of the car moves in an opposite direction, due to the kinematic phenomena described

'previously, it brings about the simultaneous closure of the doors of the car and of those at the floor, both with the wings sliding ^* vertically one towards the other. The advantages of this invention are clear.

The dragging by the electric motor in the car, by means of the kinematic motions described, of the carriage positioned at each fl@ør and the translation of the horizontal motion of the carriages of the car and of the carriages at the floor into a vertical motion of the door wings, are

performed by simple, safe, reliable and economical means, solving those problems which at present are unsolved, with considerable advantages and a significant advance in this technological field. The characteristics and the objects of the invention are made even clearer by the example of execution hereunder accompanied by schematic drawings.

Example of execution

Fig. 1) Diagram of the door installation at the floor Fig. 2) Diagram of the door installation in the car

The door at a floor is formed by two wings 10 and 11 slidng vertically (Fig. 1).

The carriage 12 comprising the rollers 13 and 14, in a pair, placed virtually at the two ends of this carriage can slide horizontally on the upper part of the installation 9 of the door.

On both sides of the carriage and a short distance from the two ends of the space in which the door wings slide the toothed wheels 20 and 21, supported idly on pins, are connected by the horizontal annular chain whose ends 26 an

27 are fastened respectively to the two sides of the carriage itself.

Integral with the wheels 20 and 21 are respectively another two toothed wheels 22 and 23 having the same diameter as th first, being covered by the wheels 20 and 21 in the diagra

in Figure 1.

The wheel 20 is integral with the wheel 22 while the wheel 21 is integral with the wheel 23.

The chain 31 with two parallel and vertical branches 32 and 33 engages on the toothed wheel 22.

The end 34 of the branch 32 is fastened to the arm 35 of the upper wing 10 of the door while the end 36 of the branch 33 of the chain is fastened to the arm 37 of the lower wing 11. The chain 40 with two parallel and vertical branches 41 and 42 engages on the toothed wheel 23.

The end 43 of the section 41 is fastened onto the arm 44 of the upper wing 10 of the door while the other end 45 of the branch 42 is fastened to the arm 46 of the lower wing 11. As is clear from the diagram, when the carriage 12 is on the right of the drawing with its vertical axis coinciding with the geometrical axis 28 of the installation indicated in this Figure 1, the wings 10 and 11 are positioned one against the other when the door is in the closed position but if the carriage is moved in the direction of the arrow 29, it will drag the chain 25 in the direction indicated by the small arrows creating a movement of rotation of the wheels 20 and 21 and thus of the wheels 22 and 23 in a clockwise direction. Consequently the end 34 of the chain 31 dragged by the wheel 22 will rise at the same time as the end 43 of the chain 40

dragged by the wheel 23 rises and therefore simultaneous to the rise of the upper wing 10.

At the same time the simultaneous lowering of the end 36 of the chain 31 and of the end 45 of the chain 40 respectively integral with the lower wing 11, will cause the latter to lower resulting in the open position of the door.

In Figure 1, 10' and 11' denote respectively the intermediate positions of the wings 10 and 11 in the phase of opening. If the carriage 12 moves in an opposite direction to the arrow 29 the said phenomena will reverse and the door will return to the closed position corresponding to that of Fig.

1).

The installation 50 of the door of the car (Fig. 2) comprises the upper wing 51 and the lower wing 52 sliding vertically.

On the top of the car the coupling carriage 53 can slide horizontally.

On both sides of this carriage, at the two ends of the car, the toothed wheels 54 and 55 are supported idly on pins and connected by the horizontal annular chain 56 whose ends 57 and 58 are fastened respectively to the two sides of the carriage itself.

To the toothed wheels 54 and 55 are respectively integral other toothed wheels 60 and 61 having the same diameter as

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the first, being covered by the said toothed wheels 54 and 55 in the diagram in Fig. 2.

The chain 62 with two vertical and parallel branches 63 and 64 engages on the toothed wheel 60. The end 65 of the branch 63 is fastened to the arm 66 of the upper wing 51 of the door while the other end 67 is fastened to the arm 68 of the lower wing 52.

The chain 70 with two vertical and parallel branches 71 and 72 engages on the toothed wheel 61. The end 73 of the branch 71 is fastened to the arm 74 integral tt the upper wing 51 while the other end 75 is fastened to the arm 76 integral with lower wing 52. Positioned on the top of the car is the motor 80 and the reduction assembly 81 which, by means of the wheels 82, 83, 84, 85 and the chains 90, 91, 92, drive the toothed wheel 93, integral with the toothed wheel 55, and covered by the latter inT?ιg. 2. Fixed on the carriage 53 is the thrusting means composed of the pair of vertical elements 94 and 95 whose width is virtually equal to the distance between the rollers 13 and 14 of the carriage 12 positioned in the installation 9 at each floor illustrated in Fig. 1) . When the car, obviously with the doors closed, (Fig. 2) reaches the door at a floor (Fig. 1) the pair of vertical eleme'nts 94 and 95 of the coupling carriage 53 move into position between the pair of rollers 13 and 14 of the

carriage 12 of the installation at the floor. The axis of the carriage 12 at the floor and the axis of the carriage 53 of the car coincide with the geometrical axis 28 indicated in Figures 1 and 2. The horizontal movement of the carriage 53, due to the motion of the motor 80 and of the reduction assembly 81 in the direction of the arrow 100 (Fig. 2), cause by the action of the element 94 on the roller 13 the translation of the carriage 12 together with said carriage 53 of the installation in the car and therefore, due to the kinematic phenomena already described, the simultaneous opening of the doors of the car and of those at the floor.

This opening will occur with the simultaneous raising of the upper wings and with the simultaneous lowering of the lower wings respectively of the car and of those at the floor.

As is clear the two carriages 12 and 53, the first dragged by the second, during the opening of the doors, move horizontally, determining however by this motion the vertical movement, respectively in opposite directions, of the two wings of the door of the car and of the door at the floor.

What is described for the floor and illustrated in Fig. 1) is also true for the other floors taking into consideration the generical diagram in Fig. 1) for all the installations of each floor.

Naturally all the movements described take place in reverse when the doors have to be closed.

For this closure it is therefore sufficient for the electric motor of the car to be controlled to run in an opposite direction to the motion which brought about the opening of the doors.