EP0810177A1

EP0810177A1 - Control equipment for lift doors

Info

Publication number: EP0810177A1
Application number: EP97108353A
Authority: EP
Inventors: Nicola Tesio
Original assignee: TESIO Srl
Current assignee: TESIO Srl
Priority date: 1996-05-28
Filing date: 1997-05-23
Publication date: 1997-12-03
Also published as: IT1285374B1; ITTO960461A1; ITTO960461A0

Abstract

Control equipment for lift doors includes a support structure (12) having guides (24, 26) along which two carriages (20, 22) for carrying respective door panels (16, 18) can run. The equipment includes a screw (34) and nut (40) drive mechanism associated with a motor (32) and adapted to drive the translational movement of the slower carriage (20). A flexible transmission member (50) is interposed between the slower carriage (20) and the faster carriage (22) and cooperates with a pair of transmission members (48) carried by the slower carriage (20).

Description

The present invention relates to equipment for controlling lift doors.
The present invention has been developed specifically to actuate lift doors including two panels movable in concordant directions between an open position and a closed position. In lifts of this type, one of the two door panels must travel twice the distance of the other door panel during an opening or closing movement. Hence the control equipment must be able to drive the two door panels at different speeds and, more precisely, the door panel which effects the longer travel must be moved at about twice the speed of the door panel which effects the shorter movement.
Various devices have already been proposed which enable this type of movement to be achieved but the main problem with these known devices is that they consist of a large number of components which take up a lot of space and are expensive.
The object of the present invention is to provide simple and reliable control equipment with as small a number of components as possible.
According to the present invention, this object is achieved by equipment having the characteristics forming the subject of the claims.
Further characteristics and advantages of the present invention will become clearer from the detailed description which follows, given purely by way of non-limitative example, with reference to the appended drawings, in which:

Figures 1 and 2 are schematic perspective views illustrating the equipment according to the invention in the open and closed positions of the door respectively,
Figure 3 is a front elevational view of the part indicated by the arrow III in Figure 2,
Figure 4 is a section taken on the line IV-IV of Figure 1,
Figures 5 and 6 are perspective views of the part indicated by the arrow V in Figure 1, on an enlarged scale,
Figure 7 is a front elevational view of the part indicated by the arrow VII in Figure 2,
Figure 8 is a partially sectioned plan view taken on the arrow VIII of Figure 7, and
Figure 9 is a schematic view illustrating the transmission equipment between the two carriages.

With reference initially to Figures 1 and 2, control equipment for lift doors is generally indicated 10 and includes a support structure 12 intended to be fixed to the lift cabin. In the drawings, the door opening of the cabin is indicated 14 and two sliding door panels, which are moved from an open position illustrated in Figure 1 to a closed position illustrated in Figure 2 and vice versa, are indicated 16 and 18. In the open position of Figure 1, the leading and trailing front edges respectively of the two door panels 16 and 18 are substantially alongside each other and the two panels are to one side of the door opening 14. In the closed position of Figure 2, the rear trailing edge of the panel 18 is partially superposed over the leading edge of the panel 16 so as to close the opening 14 completely. Hence, during the opening and closing movements, the panel 18 must travel twice the distance travelled by the panel 16. Given that the opening and closing times are the same for the two panels, the equipment 10 must be able to move the panel 18 at substantially twice the speed of the panel 16.
The panels 16 and 18 are carried by respective carriages 20 and 22 which will be termed the slow carriage and the fast carriage below for brevity. The carriages 20 and 22 have freely-rotatable wheels indicated 28 and 30 in Figure 4 whereby they run along respective guides 24 and 26.
As seen in Figure 1, the guides 24 and 26 are carried by the stationary support structure 12 and are of different lengths because of the different translational movements of the carriages 20 and 22.
The support structure 12 carries an electric motor 32 which could be a DC or an AC motor, associated with an electronic control unit, not illustrated. The motor 32 rotates a screw 34 carried by two end supports 36. The supports 36 also carry a pair of guide rods 38 along which a nut 40 is movable, the nut engaging the screw 34.
The nut 40 is connected to the slow carriage 20 by an automatic release and engagement device 42 which will be described in detail below. The length of the travel of the nut 40, indicated A in Figures 1 and 2, is equal to that of the travel of the carriage 20 from the open position of Figure 1 to the closed position of Figure 2.
With particular reference to Figure 9, the movement of the carriage 20 is transmitted to the fast carriage 22 through a speed-multiplier transmission device 44. The device 44 comprises a flange 46 fixed to the slow carriage 20 and carrying two idle transmission members 48 constituted, for example, by pulleys. A transmission member 50 constituted for example by a belt, cable or the like, passes over the transmission members 48. One pass of the transmission member 50 is fixed to the stationary structure 12 by means of an anchoring element indicated 52. The other pass of the transmission member 50 carries a thrust element 54 which engages the fast carriage 22. The transmission device 44 causes the pass of the transmission member 50 carrying the thrust element 54 to move at a velocity equal to 2V, where V is the translational velocity of the carriage 20 (equivalent to the linear translational velocity of the axes of rotation of the pulleys 48), this velocity 2V being transmitted to the fast carriage 22.
With reference now to Figures 1 and 7, the fast carriage 22 carries a pair of plates 56 and 58 which are movable relative to the fast carriage 22 between a spaced position (Figure 1) and a juxtaposed position (Figure 7). The plates 56 and 58 are slidable by means of pins 60 and 62 carried by the fast carriage 22 and slidably engaged in respective slots 64 and 66. The plates 56 and 58 also have vertical slots 68 and 70 engaged by respective pins 72 and 74 carried by a rocker arm 76 carried by the fast carriage 22 so as to be freely rotatable about the point 78. The interconnection of the two plates 56 and 58 by means of the pivotable rocker arm 76 means that, if only one of the two plates 56 is moved horizontally, the other plate is moved in the opposite direction.
The two plates 56 and 58 have respective integral flanges 80 and 82 which project from the plates 56 and 58 perpendicular to the planes thereof. The flanges 80 and 82 are intended to engage and release a generally known mechanism which can lock the landing doors (not illustrated) in their closed position. When the door of the lift cabin is closed, the two flanges 80 and 82 are juxtaposed, as illustrated in Figure 7 and, in this position, the locking mechanism for the landing doors is locked. The landing doors are released in generally known manner by the movement of the flanges 82 from their juxtaposed positions to their spaced positions.
With reference to Figure 8, it may be seen that the thrust element 54 fixed to the transmission member 50 (constituted, in the embodiment illustrated in Figure 8, by a cable) is fixed to the plate 56 by screws 84. The thrust element 54 bears against a helical compression spring 86, the other end of which acts against a stop 88 fixed to the fast carriage 22.
Still with reference to Figure 8, during the closure of the door, the flexible transmission member 50 moves in the direction indicated by the arrow 92. The thrust element 54 applies a force to the fast carriage 22 through the spring 86. The spring 86 is sufficiently stiff for it not to be compressed at all as long as the fast carriage 22 is free to run on its guide. When the fast carriage 22 reaches the end of its closing travel, it contacts an abutment 90 fixed to the support structure 12. The flexible transmission member 50 travels a further distance in the direction indicated by the arrow 92 and compresses the helical spring 86 between the stop 88 fixed to the fast carriage 22 and the thrust element 54 fixed to the transmission member 50. This additional travel of the thrust member 54 causes the plate 56 to move through the same distance in the direction 92 relative to the fast carriage 22. Consequently, the two plates 56, 58 are moved from their spaced positions to their juxtaposed positions.
Starting from the configuration illustrated in Figure 8 in which the door is closed, the opening command for the doors causes the flexible transmission member 50 to move in the direction indicated by the arrow 94 in Figure 8. As a result of this movement, the helical spring 86, which had previously been compressed, extends in a first phase and hence causes the plates 56 and 58 to move from their spaced positions to their juxtaposed positions. The further movement of the flexible transmission member 50 in the direction 94 is transmitted directly from the plate 56 to the carriage 22 since the pins 60 bear against the ends of the respective slots 64.
With reference now to Figures 5 and 6, the operation of the automatic engagement and release device 42 which connects the slow carriage 20 to the nut 40 will now be described. The device 42 includes a coupling member 96 which is articulated to the slow carriage 20 about an axis 98 and is movable between a raised position, illustrated in Figure 5, and a lowered position illustrated in Figure 6. The coupling member 96 has a first coupling portion 99 formed with a recess 100 connected to a wedge surface 102. The recess 100 is intended to engage a second coupling member constituted, for example, by a pin 104 fixed to the nut 40.
The coupling member 96 also has a second coupling portion 106 formed with a recess 108 and an inclined lead-in surface 110.
As also visible in Figure 3, the pivotable coupling member 96 has a slot 112 through which a rod 114 extends with clearance, the rod having a head 116 which can bear on the upper face of the coupling member 96. The rod 114 extends with clearance through an aperture in an abutment element 118 fixed to the slow carriage 20. The rod 114 is formed with two shoulders 120 and 122, both rigid with the rod. The shoulder 120 (formed, for example, by a nut and lock-nut pair) is intended to bear on the upper surface of the abutment element 118. A helical compression spring 124 is disposed between the shoulder 120 and an under surface of the coupling member 96. The second shoulder 122 is located at the lower end of the rod 114 and acts on a second helical compression spring 126, the other end of which acts on an under surface of the abutment element 118.
The first spring 124 exerts a force which biases the coupling member 96 into the position shown in Figure 5. This force prevails over that of the spring 126 which, on the contrary, biases the coupling member 96 to pivot downwardly (towards the position illustrated in Figure 6). In normal operating conditions, the pin 104 fixed to the nut 40 engages the recess 100 in the coupling member 96. In this situation, illustrated in Figure 5, movements of the nut 40 in both directions are transmitted to the carriage 20 by means of the engagement and release device 42.
When, however, the door meets an obstacle during its closing movement, indicated by the arrow 130 in Figure 6, the carriage 20 remains stationary while the nut 40 continues to move in the direction 130. This causes the pin 104 to disengage the recess 100, this being made possible by the pivoting of the coupling member 96 in the direction 132, against the action of the spring 124. The device 42 thus carries out the important safety function of annulling the thrust on the door in the closing direction immediately an obstacle is encountered.
After the device 42 has been released as described above, the device 42 is re-engaged automatically immediately the nut 40 is moved in the direction indicated by the arrow 134 in Figure 6. Indeed, in this situation, the carriage 20 is stationary and the pin 104 encounters the inclined surface 102, making the coupling member 96 pivot downwardly. The coupling member 96 returns to its normal operating position, illustrated in Figure 5, immediately the pin 104 reaches the recess 100.
The second coupling portion 106 of the coupling element 96 serves to lock the lift door in the closed position.
As illustrated in Figure 3, in the closed position, the recess 108 of the second coupling portion 106 engages a pin 136 fixed to the stationary support structure 12. The engagement of the coupling member 96 with the stationary pin 136 is ensured by the spring 126 which acts on the coupling member 96 through the rod 114.

Claims

Control equipment for lift doors, comprising:
- a support structure (12) having guides (24, 26) on which two carriages (20, 22) carrying respective door panels (16, 18) can run, the carriages (20, 22) being movable in concordant directions between an open position and a closed position and vice versa,

- drive means (32) for driving the translational movements of the carriages (20, 22), and

- transmission means for imparting a translational velocity to one of the carriages (22) which is substantially twice that of the other carriage (20), characterised in that it includes a screw (34) and nut (40) drive mechanism associated with the drive means (32) for driving the translational movement of the slower carriage (20) and a transmission device (44) interposed between the slower carriage (20) and the faster carriage (22), the transmission device including a flexible transmission member (50) which cooperates with a pair of transmission members (48) carried by the slower carriage (20), the flexible transmission member (50) carrying a thrust element (54) for transmitting the movement to the faster carriage (22).
Equipment according to Claim 1, characterised in that it includes an automatic engagement and release device (42) interposed between the nut (40) and the slower carriage (20) for releasing the carriage (20) from engagement with the nut (40) when the door (16, 18) encounters an obstacle during a closure phase.
Equipment according to Claim 2, characterised in that the automatic engagement and release device comprises a pair of coupling members (96, 104) carried by the slower carriage (20) and the nut (40) respectively, at least one (96) of which is movable between positions in which it is engaged with and disengaged from the other member (34) and in that resilient means (124) are provided for biasing the coupling members (96, 104) to the mutually engaged position.
Equipment according to Claim 1, characterised in that the faster carriage (22) carries a pair of plates (56, 58) having respective flanges (80, 82) movable in opposite directions relative to the carriage (22) between a mutually spaced position and a juxtaposed position, the flanges (80, 82) being adapted to engage and release a mechanism for locking the landing doors in their closed position as a result of their movement from their juxtaposed position to their spaced position.
Equipment according to Claim 4, characterised in that the thrust element (54) of the flexible transmission member (50) is fixed to one of the plates (56) and in that a resilient member (86) is interposed between the thrust element (54) and the faster carriage (22) so that, when the faster carriage (22) reaches its closed position, the thrust element (54) travels a further distance so as to compress the resilient element (86) and cause the plate (56) associated therewith to move relative to the carriage (22).
Equipment according to Claim 5, characterised in that the automatic release and engagement device (42) includes a coupling portion (106) for engaging a fixed abutment (136) in the closed position of the door (16, 18), resilient means (126) being provided to maintain the coupling portion (106) and the fixed abutment (136) in a mutually coupled position.