EP3310699B1 - Safety device of a lift system - Google Patents

Description

The invention relates to a safety device of an elevator system with a reduced shaft height and an elevator system with such a safety device.

Elevator systems have a large number of safety devices in order to prevent uncontrolled movement of a car in the elevator system. A distinction is typically made here between safety devices that are used during normal travel of the elevator car and safety devices for maintenance personnel. Normal travel is understood to mean the typical operation of the elevator system when transporting passengers. In contrast, safety devices for maintenance personnel also cover inspection trips. The inspection run of a car is understood to mean the movement for inspection and maintenance purposes. For example, maintenance personnel can be on the roof of the elevator car during an inspection trip.

From the DE 699 38 524 T2 and the EP 2 033 927 A1 various safety devices for inspection trips are known. In particular, both documents deal with foldable railings on the car roof.

The EP 2 457 860 A2 on the other hand, discloses a safety device to prevent uncontrolled movement of a car with open doors during normal travel.

The U.S. 2009/0288920 A1 discloses an elevator system with a safety zone above and below the car in the respective shaft ends. Two end position switches are provided, one for normal travel and one for inspection travel. In order to determine which end position switch is to be observed in the respective operating mode, the operating mode is read out from the elevator control. If necessary, the car is braked if it is determined by means of the end position switch to be observed that the car is about to enter the respective safety zone.

The object of the present invention is to provide an elevator system that ensures both the safety of the passengers during a normal journey and the safety of the maintenance personnel on the car roof during an inspection journey.

This object is achieved by a safety device according to claim 1. By means of the evaluation device, based on output signals from the measuring device, it is possible to recognize that at least one door zone has been left with an open car door or that impermissible accelerations and/or speeds of the car have been reached within the door zone, and a control signal can be generated. due to which the car is braked. In particular, the safety device can also be further developed in such a way that, using the evaluation device based on output signals from the measuring device, both the leaving of at least one door zone with an open car door and the reaching of impermissible accelerations and/or speeds of the car within the door zone can be detected and a control signal can be generated is due to which the car is braked.

Furthermore, the safety device has a safety circuit connected to the evaluation device to ensure a first safe zone in the shaft head of an elevator shaft during an inspection run. The safety circuit has a safety switch and the car includes a triggering device for triggering the safety switch. In this case, the safety switch and the triggering means have a first position relative to one another, in which their position relative to one another defines the first safe zone in the elevator shaft, so that the car can be prevented from entering the first safe zone during the inspection trip by triggering the safety switch by using the evaluation device can generate the same control signal due to the triggering of the safety switch, on the basis of which the elevator car is braked.

According to the invention, the position of the safety switch and/or the triggering device can be changed and can have a second position relative to one another, in which their position relative to one another defines a second safe zone in the elevator shaft, so that an elevator car can enter the second safe zone during normal travel Triggering of the safety switch can be prevented. In this configuration, due to the triggering of the safety switch, the evaluation device can generate the same control signal on the basis of which the elevator car is braked. This variant has the additional advantage that the safety circuit is also used during normal travel. Even with normal driving it is necessary to provide a second safe zone in the chess head, into which the car cannot enter. However, the second secure zone has a vertical extent that is less than the vertical extent of the first secure zone. This is typically solved by providing an additional mechanism. This can be a limit switch on the counterweight buffer, for example. The simultaneous use of the safety circuit for this purpose makes it possible to dispense with the additional mechanism.

This has several advantages. Because the safety device ensures both braking during normal travel with the doors open and braking of the elevator car during an inspection travel, the number of safety-relevant components in the elevator installation can be reduced. According to the structural regulations, it is necessary for the safety device to bring the car to a standstill within a predefined stopping distance in the event of an unintentional journey with the doors open. This stopping distance must be guaranteed for all possible states of the elevator system, for example for all possible loads in the elevator car. In order to ensure this, the entire safety chain between the triggering of the measuring device, evaluation of output signals from the measuring device by an evaluation device, up to the activation of a braking mechanism by the evaluation device and the braking behavior of the braking mechanism must be checked and calculated separately. For example, any time delay in the evaluation of the output signals leads to a longer stopping distance. This check and calculation must be carried out for all load situations, since, for example, the braking effect of the braking mechanism depends on the loading status of the car. Accordingly, it is also necessary for the elevator car to be brought to a standstill in good time by the safety device during an inspection trip, so that there is always sufficient safety space on the roof of the elevator car for the maintenance personnel. The same complex calculation and testing of the safety chain is required for this in order to be able to guarantee compliance with the specified stopping distance. The partial combination of the two safety chains (from the evaluation unit to the braking mechanism) according to the invention significantly reduces the effort involved in testing and calculating the corresponding components. Since the evaluation device generates the identical control signal for the braking mechanism in both cases (travel with open doors outside a door zone, undesired entry into the shaft head), the maximum stopping distance is also identical in both cases.

In addition, a simplification of the certification of the elevator installation can also result. According to the standards for elevator systems, some countries require certain safety devices to be certified by independent testing institutes. By partially merging the two safety chains, it may be possible to obtain simplified certification for safeguarding the inspection drive, since the corresponding components are at least partially already certified in connection with a normal drive.

The triggering means for triggering the safety switch is in particular an emergency limit switch curve. This includes, in particular, a running track which is arranged at a slight angle to the vertical and which is connected to the elevator car. When the car enters the shaft head, the safety switch and the emergency limit switch curve engage with each other. Due to the slight inclination to the vertical, the safety switch is moved the more the more the car enters the shaft head. From a certain vertical position of the car and thus the emergency limit switch curve, this triggers the safety switch.

In one embodiment of the invention, the control signal is designed to switch off the drive motor. In particular, the control signal can be suitable for causing a short circuit in the drive motor. This leads to a particularly quick shutdown of the drive motor.

In a further embodiment of the invention, the control signal is designed to bring about application of the service brake. The service brake can in particular be approved as a safety brake, such as in the case of gearless drives.

The position can be changed, for example, by designing the safety switch or the triggering means to be displaceable. In particular, the triggering means is designed in such a way that it can be displaced in a receptacle on the elevator car and can latch with the receptacle both in the first position and in the second position.

In a further developed variant, the triggering means for triggering the safety switch relative to the elevator car can be adjusted between the first position and the second position in the vertical direction such that the vertical extent of the first safe zone is greater than the vertical extent of the second safe zone. The adjustment of the triggering means in the vertical direction is a variant that is structurally particularly easy to implement. In particular, the release means can be reached much more easily by maintenance personnel, since it is connected to the elevator car. The release means can therefore be moved from the first to the second position in a simple manner by the maintenance personnel. If, for example, the triggering means is an emergency limit switch curve, the adjustability can be implemented by simply pulling the emergency limit switch curve up and locking it in the second position.

In a special embodiment of the invention, the safety circuit also includes a switch for monitoring the position of the triggering means. The switch is also in signal connection with the evaluation device. When the switch is triggered due to an unintentional adjustment of the triggering means, the evaluation device generates a control signal, on the basis of which the elevator car is braked. In this way it is ensured that the elevator installation is switched off in the event of an inadvertent adjustment of the triggering means, since the elevator installation is no longer in the safe operating mode.

The invention also relates to an elevator system with a prescribed safety device. This has the same advantages as explained above with reference to the safety device.

In a special embodiment of the elevator system, the car has a railing on a car roof, which can be moved between a first position and a second position in is adjustable in the vertical direction. The railing is intended to prevent maintenance personnel from being too close to the edge of the car roof during an inspection run. In some cases, the installation of such a railing is necessary due to building regulations. The adjustability has the advantage that, on the one hand, the railing has a sufficient height during an inspection run, so that its safety purpose can be fulfilled. On the other hand, the car can still drive far into the shaft head during normal travel without being prevented by the height of the railing.

In a special development of the elevator system, the safety circuit includes an additional switch that monitors the position of the railing. For this purpose, the switch is in signal connection with the evaluation unit. This has the advantage that if the railing is unintentionally displaced (for example from the second position towards the first position), the switch is triggered. Due to the triggering of the switch, the evaluation device then generates a control signal, on the basis of which the elevator car is braked. This prevents the inspection drive from being continued in an unsafe operating mode.

In another development of the elevator installation, the railing is coupled to the triggering device in such a way that the railing and the triggering device can only be adjusted together between the first and second positions. In particular, the coupling can consist in the fact that the triggering means is attached to the railing. The coupling has the advantage that the maintenance personnel can move both the railing and the triggering means from the first to the second position with just one movement before starting an inspection run. This accelerates the start of maintenance work.

The invention also relates to a method for operating an elevator system with a car and a prescribed safety device. The evaluation device recognizes in a normal mode based on the output signal of the measuring device that at least one door zone has been left with an open car door or that impermissible accelerations and/or speeds of the car have been reached within the door zone. As soon as such an unintended journey is detected, the evaluation device generates a control signal, on the basis of which the elevator car is braked. Here, under the normal mode, the usual operation of the elevator system in the carriage understood by passengers. Normal journeys are thus carried out during the normal mode.

In the inspection mode, on the other hand, the evaluation device detects a triggering of the safety switch and, as a result, generates the same control signal, so that the car is braked. An inspection mode is understood to mean operation of the elevator system for inspection and maintenance purposes. No passengers are transported in inspection mode. Consequently, inspection trips are carried out during the inspection mode, during which, for example, maintenance personnel can be located on the roof of the elevator car. The method has the same advantages as explained above with reference to the safety device.

• Figur 1 eine schematische Darstellung einer Aufzugsanlage,
• Figur 2 eine detaillierte Darstellung des Schachtkopfes während einer Inspektionsfahrt,
• Figur 3 eine detaillierte Darstellung des Schachkopfes während einer Normalfahrt bei einer nicht erfindungsgemäßen Ausführungsvariante,
• Figur 4 eine detaillierte Darstellung des Schachtkopfes während einer Normalfahrt bei einer erfindungsgemäßen Ausführungsvariante.

The invention is explained in more detail with reference to the figures. show here

• figure 1 a schematic representation of an elevator system,
• figure 2 a detailed representation of the shaft head during an inspection drive,
• figure 3 a detailed representation of the chess head during a normal run in an embodiment variant not according to the invention,
• figure 4 a detailed representation of the shaft head during a normal journey in an embodiment variant according to the invention.

In figure 1 is a schematic representation of an elevator installation 1 with an elevator car 3, which can be moved up and down in a vertical direction in an elevator shaft 7 by means of a drive device 5, whereby it stops at various stops, of which in figure 1 only three stops 9, 11, 13 are shown, can stop to be loaded and unloaded.

The drive device 5 comprises a drive motor 15 which is controlled by a control unit 17 , a supply voltage being provided to the drive motor 15 via the control unit 17 . In addition, the drive device 5 includes a traction sheave 19 which is set in rotation by the drive motor 15 . A rope 21 is guided around the traction sheave 19 and connects the car 3 to a counterweight 23. The traction sheave 19 is a Assigned service brake 25, which is just like the control unit 17 connected to an elevator control 27.

At each stop 9, 11 and 13, zone flags 29 are arranged in the elevator shaft 7, which can be detected by a door zone sensor 31. The door zone sensor 31 is fixed to the car 3 and connected to the elevator control 27 . The zone flag 29 specifies a door zone. As long as the door zone sensor 31 detects the zone flag 29, the car 3 is within the door zone.

As already mentioned, the car 3 can be moved in the elevator shaft 7 by means of the drive device 5 . For loading and unloading, the elevator car 3 can assume a position flush with a stop 9, 11, 13. The weight of the car 3 changes as a result of the loading and unloading. This can lead to the car 3 changing its position relative to the stops 9, 11, 13 slightly. The position of the elevator car 3 can then be readjusted relative to the respective stop 9, 11, 13 by activating the drive device 5. The adjustment movement takes place at a very low speed and very low acceleration within the door zone, which is defined by the zone flag 29 .

If the car 3 approaches a stop 9, 11, 13, the car door 33 can already be opened before the car 3 has reached its flush position. The car door 33 can be opened as soon as the door zone sensor 31 detects the zone flag 29 .

In the example described, exactly one door zone is defined for each stop 9, 11, 13. Alternatively, it is also known to define multiple door zones per stop. For example, a first door zone can be defined for the adjustment movement and a second door zone for entering a stop.

For safety reasons, it is necessary that the car 3 does not leave the door zone with the car door 33 open. Furthermore, impermissible accelerations and/or speeds of the elevator car 3 must be prevented within the door zone. This is done using the safety device. The safety device includes an evaluation unit 35 which is formed by the elevator control 27 and the control device 17 . Elevator controller 27 and control device 17 are connected to one another for this purpose with a signal connection (bidirectional electrical connection). If the elevator controller 27 receives the signal from the door zone sensor 31 that the car 3 is leaving the door zone, and if the elevator controller 27 receives it from the door sensors 37 and/or 39 at the same time the signal that at least one door leaf is not closed, the evaluation device 35 generates a control signal on the basis of which the elevator car 3 is braked. For this purpose, the evaluation device 35 has a signal connection with the service brake 25 and the drive device 5. The zone flag 29, the door zone sensor 31 and the door sensors 37, 39 are therefore part of the measuring device 45 for monitoring the car status.

The result of the control signal is that the service brake 25 is activated and also that the drive motor 15 is switched off. It is also possible that the control signal only activates the service brake 25 or only switches off the drive motor 15 . Other known braking methods for a car 3 based on the control signal are also possible.

figure 2 12 shows a representation of the shaft head 47 of an elevator shaft 7. The elevator car 3 is located in the elevator shaft 7. The elevator car 3 can be moved along the guide rails 57 in the elevator shaft 7. FIG. in the in figure 2 illustrated operating mode, the elevator car 3 carries out an inspection trip. An emergency limit switch curve 49 is arranged on the car 3 . When driving into the shaft head 47, the emergency switch curve 49 triggers the safety switch 51, which is connected to the shaft wall in the shaft head 47. The safety switch 51 is part of a safety circuit that is connected to the evaluation device 35 . Due to the triggering of the safety switch 51, the evaluation device 35 generates the control signal on the basis of which the elevator car 3 is braked. As a result, a first safe zone 53 is specified in the shaft head 47, into which the car 3 cannot enter during the inspection run. Maintenance personnel who are on the car 3 during the inspection journey are thus secured against being crushed between the car 3 and the end 59 of the elevator shaft. In contrast to a normal trip, a significantly larger safety space above the car roof must be ensured for an inspection trip, since maintenance personnel can be on the car roof. However, it must be taken into account here that the elevator car still covers a certain stopping distance 55 between the triggering of the safety switch 51 and the complete standstill of the elevator car 3 . In order to be able to reliably prevent maintenance personnel from being crushed, the length of the stopping path 55 must be precisely known and also reproducible. All components that influence the length of the stopping distance 55 must be precisely determined and checked. In some cases, a special test or separate certification of the components is required for this. this concerns in particular the evaluation device 35, as well as all components that contribute to the deceleration of the elevator car 3. In the above example, these are the service brake 25, the drive motor 15 and the signal connection to these components. According to the invention, the evaluation device 35 generates the same control signal with which the car 3 is also braked when driving with the door leaves open outside a door zone. This has the advantage that the same components, which are subjected to a special test or separate certification for safety reasons, can be used for two fundamentally different applications. In this way, the number of specially tested components can be kept lower.

figure 3 shows the same shaft head 47 during normal travel of the elevator car 3 in an embodiment variant that is not according to the invention.

Compared to the representation in figure 2 the emergency limit switch curve 49 is offset downwards in the vertical direction in relation to the car 3 . The emergency limit switch cam 49 and the safety switch 51 thus have a second position relative to one another. In this second position, the elevator car 3 can move much further into the shaft head 47 and thus into the first safe zone without triggering the safety switch 51 . The distance between the car 3 and the end of the elevator shaft 59 is significantly smaller than in the illustration figure 2 . In this case, the end position of the elevator car 3 is ensured by an additional mechanism. This can be a known limit switch on the counterweight buffer, for example. The safety circuit with the safety switch 51 is therefore inactive.

In order to prevent the emergency limit switch curve 49 from accidentally leaving the first position during an inspection run, so that entry into the first safe zone 53 can no longer be reliably prevented, the safety circuit has a switch 61 that continuously monitors the position of the emergency limit switch -Curve 49 monitored. When the emergency limit switch curve 49 is displaced, the evaluation device 35 generates a control signal based on the triggering of the switch 61, on the basis of which the elevator car 3 is braked.

Before the start of an inspection trip, the maintenance personnel go onto the roof of the elevator car 3 and move the emergency limit switch cam 49 from the second position to the first position. This activates the switch 61, activates the safety circuit and prevents the car 3 from entering the first safe zone. An inspection run can only be carried out after the safety circuit has been activated. After completion of the For maintenance work, the emergency limit switch curve 49 is returned to the second position so that the car 3 can enter the first safe zone again.

figure 4 shows a variant of the elevator system 1 according to the invention during normal travel of the car 3. Compared to the illustration in FIG figure 2 Here, too, the emergency limit switch curve 49 is offset downwards in relation to the car 3. The emergency limit switch curve 49 and the safety switch 51 thus have a second position relative to one another. In contrast to the in figure 3 However, in the variant shown, the safety circuit is also active during normal travel and determines the end position of the car 3 in the elevator shaft 7 . Consequently, no additional mechanism is required to ensure the end position of the elevator car 3 . In the second position, the safety switch 51 and the emergency limit switch curve 49 specify a second safe zone 63 in the elevator shaft through their position relative to one another, so that the car 3 is prevented from entering the second safe zone 63 during normal travel by triggering the safety switch 51. The first safe zone 53 has a vertical extent that is greater than the vertical extent of the second safe zone 63 based on a comparison of FIG figures 2 and 4 is clearly recognizable. The same emergency limit switch curve 49 that appears during an inspection run ( figure 2 ) prevents the car 3 from entering the first safe zone 53, also prevents during normal travel ( figure 4 ) driving car 3 into the second safe zone 63. In both cases, the emergency limit switch curve 49 triggers the safety switch 51, whereupon the evaluation device 35 generates the control signal, on the basis of which the car 3 is braked.

In a further developed embodiment of the invention, the car 3 has a railing 65 on the car roof (also shown in FIGS Figures 2 to 4 shown). Such a railing 65 can be absolutely necessary due to building regulations during an inspection trip. The railing 65 can, for example, be designed to be foldable, so that it is only folded out during an inspection trip, or it can be designed to be variable in height, as is shown in FIGS Figures 2-4 is shown. During an inspection drive ( figure 2 ) the railing 65 is in a first position, thus preventing maintenance personnel from getting too close to the edge of the car roof and ensuring that it does not fall. During a normal drive ( figure 3 or. figure 4 ) is the railing 65 in a second position in which it has a significantly smaller vertical extent. The car can therefore move much further into the shaft head than would be possible with the railing in the first position

In order to prevent the railing 65 from accidentally leaving the first position during an inspection run, so that the safety of the maintenance personnel can no longer be adequately guaranteed, the safety circuit has a switch 67 which continuously monitors the position of the railing 65 . When the railing 65 is displaced, the evaluation device 35 generates a control signal based on the triggering of the switch 67, on the basis of which the elevator car 3 is braked.

Before starting an inspection trip, the maintenance personnel go onto the roof of the car 3 and move the railing 65 from the second position to the first position. As a result, the switch 67 is triggered, the safety circuit is activated and the elevator car 3 is prevented from entering the first safe zone 53 . An inspection run can only be carried out after the safety circuit has been activated. After the maintenance work has been completed, the railing 65 is brought back into the second position, so that the elevator car 3 can enter the first safe zone again. <b>Reference List</b> elevator system 1 car 3 drive device 5 elevator shaft 7 bus stop 9 bus stop 11 bus stop 13 drive motor 15 control unit 17 traction sheave 19 Rope 21 counterweight 23 service brake 25 elevator control 27 zone flag 29 door zone sensor 31 car door 33 evaluation device 35 door sensor 37 door sensor 39 door leaf 41 door leaf 43 measuring device 45 shaft head 47 Emergency limit switch curve 49 safety switch 51 First safe zone 53 stopping distance 55 guide rail 57 shaft end 59 Switch 61 Second Safe Zone 63 railing 65 Switch 67

Claims (10)

1. Safety device of an elevator system (1) having an elevator car,

   comprising an evaluation device (35) and a measuring device (45), wherein, by means of the evaluation device (35), by using output signals from the measuring device (45), departure from at least one door zone with an open elevator car door (33) or reaching impermissible accelerations and/or speeds of the elevator car (3) within the door zone can be detected and a control signal, on the basis of which the elevator car (3) is braked, can be generated,

   wherein the safety device has a safety circuit that is connected to the evaluation device (35) in order to ensure a first safe zone in the shaft head of an elevator shaft (7) during an inspection run,

   wherein the safety circuit has a safety switch (51) and wherein the elevator car (3) comprises a tripping means for tripping the safety switch (51),

   wherein the safety switch (51) and the tripping means have a first position relative to each other in which, by means of their position relative to each other, they predefine the first safe zone (53) in the elevator shaft, so that the elevator car (3) can be prevented from moving into the first safe zone (53) during the inspection run by tripping the safety switch (51) in that, by means of the evaluation device (35), the control signal on the basis of which the elevator car (3) is braked can be generated on the basis of the tripping of the safety switch (51),

   characterized in that

   the safety switch (51) and/or the tripping means are variable in their position and can have a second position relative to each other in which, by means of their position relative to each other, they predefine a second safe zone (63) in the elevator shaft (7), so that an elevator car (3) can be prevented from moving into the second safe zone during a normal run by tripping the safety switch (51),

   wherein, by means of the evaluation device (35), the same control signal on the basis of which the elevator car (3) is braked can be generated on the basis of the tripping of the safety switch (51).
2. Safety device according to Claim 1,
   characterized in that
   the control signal is designed to effect deactivation of a drive motor (15).
3. Safety device according to one of the preceding claims,
   characterized in that
   the control signal is designed to effect engagement of an operating brake (25).
4. Safety device according to one of the preceding claims,
   characterized in that
   the tripping means for tripping the safety switch (51) can be displaced in the vertical direction with respect to the elevator car (3) between the first position and the second position in such a way that the vertical extent of the first safe zone (53) is greater than the vertical extent of the second safe zone (63).
5. Safety device according to one of the preceding claims,
   characterized in that
   the safety circuit has a switch (61) for monitoring the position of the tripping means.
6. Elevator system (1) comprising an elevator car (3) which can be moved in an elevator shaft (7), comprising a safety device according to one of the preceding claims.
7. Elevator system according to the preceding claim,
   characterized in that
   the elevator car (3) has a handrail (65) on an elevator car roof, which can be displaced in the vertical direction between a first position and a second position.
8. Elevator system (1) according to the preceding claim,
   characterized in that
   the safety circuit comprises a further switch (67), which monitors the position of the handrail (65).
9. Elevator system according to either of Claims 7 and 8,
   characterized in that
   the handrail (65) is coupled to the tripping means in such a way that the handrail (65) and the tripping means are displaceable only jointly between the first and the second position.
10. Method for operating an elevator system (1) having an elevator car (3) and a safety device according to one of Claims 1 to 5,

    wherein in a normal mode, on the basis of output signals from the measuring device (45), the evaluation device (35) detects the departure from at least one door zone with an open elevator car door (33) or the reaching of impermissible accelerations and/or speeds of the elevator car (3) within the door zone and generates a control signal, on the basis of which the elevator car (3) is braked,

    and wherein, in an inspection mode, on the basis of the tripping of the safety switch (51), the evaluation device (35) generates the control system on the basis of which the elevator car (3) is braked.

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