Elevator system with safety circuit and method for operating same

Abstract

The following embodiments relate to an elevator system (1), having an elevator shaft (2) with a shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6), a first elevator car (3.1) with a first elevator car door (4.1), and a first drive device, wherein the first elevator car door (4.1) has a first safety contact (8) which makes contact when the first elevator car door (4.1) is closed, and the shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6) has a second safety contact (9) which makes contact when the shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6) is closed, wherein the first safety contact (8) and the second safety contact (9) are connected in series in a safety circuit (13), wherein the safety circuit (13) is designed in such a way that an operation of the first drive device (6.1) is possible only when the safety circuit (13) is closed, wherein the safety circuit (13) has a switchable bridging (16) of the safety contacts (8, 9) and wherein the safety circuit (13) has an isolating switch (18) behind the two safety contacts (8, 9) and in front of a return (19) of the bridging (16) to the safety circuit (13).

Description

[0001] TD 41980 - 1 - October 2025

[0002] Elevator system with safety circuit and method for operating such a system

[0003] Technical field

[0004] The following descriptions relate to an elevator system comprising an elevator shaft with a shaft door, a first car movable along the elevator shaft with a first car door, and a first drive device for driving the first car, wherein the first car door has a first safety contact that makes contact when the first car door is closed, and the shaft door has a second safety contact that makes contact when the shaft door is closed, wherein the first

[0005] The safety contact and the second safety contact are connected in series in a safety circuit, and the safety circuit is designed in such a way that operation of the first drive device is only possible when the safety circuit is closed.

[0006] Furthermore, the following explanations concern a procedure for operating such an elevator system when starting a journey from an open first car door and an open shaft door.

[0007] Technical background

[0008] Elevator systems for transporting people and / or goods are an integral part of modern residential and commercial buildings. A typical elevator system comprises one or more elevator shafts, in each of which one or more cars are moved between landing positions by means of drives such as suspension drives or linear drives.

[0009] In such elevator systems, there is a constant need to minimize travel times and thus maximize the elevator's transport capacity. Furthermore, it is known that car doors and shaft doors are equipped with safety contacts, whereby the safety contacts of the elevator system form a safety circuit and prevent the drive of a respective car from being stopped. (TD 41980 - 2 - October 2025)

[0010] The elevator system can only operate if the respective door and thus the safety circuit are closed, in order to prevent injury to passengers at open doors when the elevator car is moving.

[0011] In accordance with the aforementioned ongoing need, it is known that the safety contacts of a car door and a shaft door can be bypassed when the car is directly at the shaft door and moving only slightly. In this way, the doors can begin to open before the car has come to a complete stop, thus reducing the time the car spends at the shaft door.

[0012] Based on this situation, the task at hand is to propose an elevator system in which the dwell time of the elevator car at a shaft door can be reduced.

[0013] Description - Technical Solution

[0014] The present problem is solved by the features of the independent claims. Advantageous embodiments are specified in the dependent claims, the description, and the drawings. Where technically feasible, the teachings of the dependent claims can be combined arbitrarily with those of the main and dependent claims.

[0015] In particular, the problem is solved by an elevator system comprising an elevator shaft with a shaft door, a first car movable along the elevator shaft with a first car door, and a first drive device for driving the first car, wherein the first car door has a first safety contact that makes contact when the first car door is closed, and the shaft door has a second safety contact that makes contact when the shaft door is closed, wherein the first safety contact and the second safety contact are connected in series in a safety circuit, wherein the safety circuit is designed such that operation of the first drive device is only possible when the safety circuit is closed.wherein the safety circuit has a switchable bridging of the first safety contact and the second safety contact and wherein the safety circuit has a disconnect switch behind both TD 41980 - 3 - October 2025,

[0016] safety contacts and before the bridging is returned to the safety circuit.

[0017] The following sections explain advantageous aspects and subsequently describe preferred modified embodiments. Explanations, particularly regarding advantages and definitions of features, are essentially descriptive and preferred, but not limiting, examples. If an explanation is limiting, this will be explicitly stated.

[0018] Where ordinal numbers, such as "first," "second," etc., are used, for example to designate a component, an element, a process step, or a process action, these ordinal numbers are solely for differentiation in the designation and do not indicate any dependencies or sequences. This means, in particular, that a device does not need to have a "first component" to have a "second component." A device can also have a "first component" and a "third component" without necessarily having a "second component." Multiple units with the same ordinal number are also possible, for example, multiple "first components."

[0019] According to the present understanding, an elevator system is designed, for example, with at least one vertical and / or horizontal elevator shaft and at least one first elevator car, but can also have several elevator shafts and / or several elevator cars, in particular several elevator cars per elevator shaft.

[0020] For example, a car is held and driven by means of a load-bearing element, wherein a drive device transmits a drive torque to the load-bearing element via a drive shaft. The load-bearing element is preferably connected to a counterweight associated with the car. A drive device is, in particular, arranged in a machine room or in the shaft head. In particular, a drive device for a car driven by means of a load-bearing element is designed as an electric machine, for whose operation a converter is provided. The converter is then, for example, supplied with electrical voltage only when the safety circuit is closed. A load-bearing element is, in particular, designed as a rope, belt, strap, chain, or the like and carries tensile loads in the direction of its longitudinal extension. TD 41980 - 4 - October 2025

[0021] Alternatively, an elevator car can be held and driven by a linear actuator. A linear actuator consists, for example, of a primary part extending along the elevator shaft and a secondary part located on the elevator car. The primary part is formed by coils arranged in a line, each with its own converter. An energizer is applied to the coil to generate a magnetic field when the elevator car is within the area of ​​the respective coil, thus moving the car. The secondary part consists of a permanent or electromagnet that interacts with the magnetic fields of the coil. Alternatively, an elevator car can also be driven by another known method, such as pneumatically or hydraulically.

[0022] An elevator shaft is a continuous shaft that extends over several floors and / or along several areas of a building and has a cross-section designed for the passage of the elevator car. An elevator shaft can extend vertically and / or horizontally.

[0023] A shaft door of the elevator shaft is arranged in a landing position, which is defined in particular by a floor or area of ​​the building. The shaft door, in conjunction with a car door, forms a passage between the car in the elevator shaft and the floor or area of ​​the building. The shaft door is formed, for example, by a door portal in a wall between the floor / area and the elevator shaft. Operating elements for sending car calls and / or information elements for displaying information concerning the elevator system are typically located on the wall outside the elevator shaft. The car door and the shaft door are designed to be mechanically coupled or to open and close synchronously when the car stops at the shaft door, either mechanically or by signal exchange. This coupled opening and closing can occur simultaneously or with a time delay.

[0024] A safety contact comprises two contact elements that, when the car door or shaft door is closed, make contact with each other, forming a conductive, closed safety contact. For example, one contact element is located in a door leaf and the other in a door frame. A safety contact is closed (TD 41980-5-October 2025) when the respective door is fully closed, and open in all other cases. If the safety contacts are connected in series, a safety circuit is closed by the safety contacts when both safety contacts are closed. Arranging the safety contacts in series does not preclude the arrangement of further circuit elements between the safety contacts.

[0025] A closed safety circuit is understood to mean, in particular, both a safety circuit in which all safety contacts connected in series are closed, and a safety circuit in which any open safety contacts are bridged by a closed jumper. A safety circuit can be formed by a physical series connection of safety contacts, or it can be formed by a bus system in which signals from individual safety contacts are combined and processed centrally. In this case, a series arrangement is, for example, digitally represented.

[0026] A switch, or its function, is understood to mean that the switch can be selectively closed to establish a conductive connection or opened to break that conductive connection. A switching operation is selectively the change from the open to the closed state or vice versa.

[0027] The aforementioned solution to the problem with an elevator system now comprises the teaching that, by providing a disconnect switch, the two safety contacts, in particular one safety contact arranged in series behind the other, are separated from the subsequent feedback of the bypass. Thus, the presence of a signal on the return side of the safety contacts, or of the safety contact furthest behind in the series, depends solely on the closed state of the safety contacts, or of the safety contact furthest behind in the series. It can then be determined for both safety contacts individually or together whether they are open or closed when the bypass is closed. Advantageously, this allows the closing states of the doors to be checked while the safety circuit is closed via the bypass, thereby enabling operation of the drive device.Preparations for travel by the drive unit, which rely on a closed safety circuit, can then begin simultaneously with the closing process of the doors (TD 41980 - 6 - October 2025). For example, such preparations include switching on contactors of the first drive unit, charging an intermediate circuit of the first drive unit, and / or releasing a brake of the first car.

[0028] Because the pre-travel preparations are carried out during the door closing process, the elevator can begin traveling immediately after the doors are fully closed, once the disconnect switch has closed and the bypass has opened. This eliminates the time-consuming process of performing pre-travel preparations after the safety circuit has been closed again via the two safety contacts. As a result, the elevator car can start traveling more quickly and / or the dwell time at the shaft door can be reduced. This reduces travel times and / or increases the elevator's transport capacity.

[0029] Furthermore, in the aforementioned elevator system, the drive mechanism is advantageously available for continuously controlling the precise position of the elevator car relative to the shaft door during the first car's stop at the shaft door, thanks to the permanently closed safety circuit. For example, after a change in the car's weight due to passengers boarding or alighting, and the resulting lifting or lowering of the car, the car position can be moved back into alignment with the shaft door or maintained in that position.

[0030] Alternatively or additionally, the switchable bypass may include a transceiver, in particular an SR module. A transceiver can be configured, on the one hand, to receive a test signal encoded with specific conditions for closing or opening the bypass, and on the other hand, to output a switching signal for closing or opening the bypass. Thus, a transceiver can both receive information about the conditions for bypassing the safety contacts and output switching signals for closing and / or opening the bypass.

[0031] Alternatively or additionally, the transceiver can be configured to close the bypass when the first car is positioned near the shaft door and below a certain speed threshold. This allows for slow and spatially limited movement of the first car (TD 41980 - 7 - October 2025) by means of the first drive device in the vicinity of the shaft door when the first car door and / or the shaft door are open. The doors can then be opened even below a low speed threshold if the first car is already in the vicinity of the shaft door when approaching it.Furthermore, during the stop and thus with the doors (fully) open, a position correction of the first car is made possible by means of the first drive device in order to maintain a level alignment of the first car to the shaft door, especially when the car weight changes due to passengers entering and / or exiting or loading or unloading goods.

[0032] Alternatively or additionally, the disconnect switch can be designed as a relay. The disconnect switch can then be opened and / or closed in response to a signal, for example, a control signal from the bypass, a control signal from a signal pickup at any point within the safety circuit, or a higher-level control system. In particular, the relay can also be controlled simultaneously by multiple signal transmitters.

[0033] Alternatively or additionally, the elevator system can be configured to open the disconnect switch when the first safety contact in the series circuit closes. At this point, when it is certain that the first safety contact in the series is closed, any signal present on the reverse side of the safety contacts then depends solely on the safety contact further down the series, so that the closed state of both safety contacts can be checked individually.

[0034] Alternatively or additionally, a first signal pickup can be provided between the safety contacts connected in series, with the safety circuit configured so that the disconnect switch is opened depending on the signal received at the first signal pickup. Thus, if the first safety contact is closed and a signal is subsequently present at the first signal pickup, the disconnect switch is opened to allow the closed state of the second safety contact to be checked individually.

[0035] Alternatively or additionally, a second signal pickup can be provided between the rear of the two safety contacts and the disconnect switch, wherein, according to TD 41980 - 8 - October 2025, the safety circuit is configured so that the disconnect switch is closed depending on the signal received at the second signal pickup. The closed state of the safety contacts, or the second safety contact, can then be verified using the second signal pickup. With the disconnect switch open, a signal is only present at the second signal pickup if both safety contacts are closed, whereby the closed state of the first safety contact can be verified by the aforementioned first signal pickup.

[0036] Alternatively or additionally, the first safety contact in the series circuit can be arranged before the second safety contact. In this case, if the doors close in stages, the car door will close first.

[0037] Alternatively or additionally, the elevator system may include a second car traveling along the elevator shaft, with a second car door and a second drive unit for propelling the second car. The elevator system is configured so that the car traveling behind the other operates at a reduced speed, reduced acceleration, and / or reduced rate of change of acceleration (jerk). The operating parameters are reduced compared to the nominal parameters or travel curve parameters intended for the car traveling behind the other car, and especially compared to the nominal parameters or travel curve parameters of the car traveling ahead. In this way, a collision between the two cars is reliably prevented, as the distance between them increases during travel.

[0038] Accordingly, a stronger deceleration and / or a greater change in deceleration when stopping may be provided for the car traveling behind the other.

[0039] Particularly advantageous is the reduction of several driving parameters over an entire travel curve, or the reduction of the entire travel curve, so that the relative distance, i.e., the speed-normalized distance, between the elevator cars is maintained or increased in every driving situation. This objective can be achieved particularly advantageously even if the following elevator car has nominally higher rated values, for example, a higher rated speed and / or a higher rated acceleration. TD 41980 - 9 - October 2025

[0040] Alternatively or additionally, it can be provided that if both elevator cars stop simultaneously in adjacent landing positions, i.e., at adjacent shaft doors, and thus in close proximity to each other, the reduced travel parameters are taken into account at the start of the journey. With a simultaneous start, it is then ensured that the distance between the elevator cars can only remain the same or increase, but not decrease. Advantageously, the start of the following elevator car can occur simultaneously with the start of the preceding elevator car. The start of the following elevator car then advantageously occurs particularly early, without the preceding elevator car having to first establish a safety distance after its own start.

[0041] Alternatively or additionally, it can be provided that if both elevator cars stop simultaneously in adjacent landing positions, i.e., at adjacent shaft doors and thus in close proximity to each other, the start of travel for the first car (if it is the one following the second car) is delayed even if the doors and thus both safety contacts are closed, as long as the second car has not yet started moving. For example, the closing of the isolating switch can be triggered, on the one hand, by the closed state of the second safety contact and, on the other hand, by a signal from the second car containing information about its start of travel.

[0042] The problem is further solved by a method for operating a previously described elevator system when starting a journey from an open first car door, an open shaft door and a closed bypass, comprising the steps: optionally closing the door assigned to the safety contact arranged in series before the other, opening the disconnect switch, performing travel preparations of the first drive device and / or the first car with the bypass closed and the disconnect switch open, closing all remaining open doors, closing the disconnect switch, opening the bypass, starting the journey of the first car.

[0043] It is preferred that the sequence of process steps may be varied, unless a specific sequence is technically required. In particular, individual steps may be varied. TD 41980 - 10 - October 2025

[0044] Doors, in particular the door assigned to the safety contact arranged before the other in the series circuit, are closed before or after the disconnect switch is opened. Furthermore, the bypass can be opened before or after the disconnect switch is closed. A switching sequence that enables a continuously closed safety circuit is preferred, especially with regard to travel preparations that do not permit an interruption of the drive unit's operation between travel preparation and the start of travel. The closing of all still-open doors occurs, in particular, simultaneously with or overlapping in time with the execution of the travel preparations of the first drive unit and / or the first elevator car.

[0045] Preparations for travel are understood to be, in particular, those measures that must be carried out before the elevator car begins to move, but which do not yet trigger the start of travel. The start of travel is understood to be when the elevator car is set in motion.

[0046] Closing all open doors means closing both the first car door and the shaft door, provided neither door was closed before the disconnect switch was opened. Closing all open doors also means closing the door associated with the safety contact located before the other in the series circuit, provided that the closing occurs before the disconnect switch is opened.

[0047] The solution to the problem using the aforementioned method essentially comprises the teaching previously described for the elevator system, applied accordingly and offering the same advantages. Thus, a safety circuit, closed via a bypass, is established by means of the disconnect switch, which is opened before all doors are closed. This allows operation of the first drive unit, while simultaneously ensuring reliable monitoring of the doors' closing status. The bypass and the disconnect switch then make it possible to perform the pre-travel preparations while the doors are still closing, allowing the elevator to begin traveling immediately after the doors close.

[0048] Alternatively or additionally, it may be provided that the execution of travel preparations for the first drive unit and / or the first car includes switching on contactors TD 41980 - 11 - October 2025 of the first drive unit, charging an intermediate circuit of the first drive unit, and / or releasing a brake of the first car. These travel preparations are relatively time-consuming and require the active operation of the drive unit. Therefore, by executing the travel preparations, the time required can be shifted to the period during which the doors close.

[0049] Alternatively or additionally, the opening of the disconnect switch can be configured to depend on the signal detected at the first signal pickup. In this case, the first safety contact is already closed due to the initial signal pickup, so that subsequently, when the disconnect switch is open, the presence of a signal on the reverse side of the safety contacts depends solely on the closed state of the safety contact further down the line in the series. The safety contacts can then advantageously be monitored individually.

[0050] Alternatively or additionally, it can be provided that the closing of the disconnect switch depends on the signal received at the second signal pickup. The disconnect switch then closes immediately after the closing of the second safety contact, and thus immediately after both doors are closed. The journey can then begin without any delay after the doors have closed.

[0051] Alternatively or additionally, the method for operating an elevator system with a second car traveling along the elevator shaft, a second car door, and a second drive unit for propelling the second car may be provided for when both cars start moving simultaneously. In this case, the car following the first car only begins moving at or after the other car has started moving. The following car therefore only starts moving when the preceding car begins moving, and not before. In particular, the isolating switch of the following car is also closed depending on a signal relating to the start of movement of the preceding car. TD 41980 - 12 - October 2025

[0052] Brief description of the drawings

[0053] A preferred technical solution is explained in more detail below with reference to the accompanying drawings and preferred embodiments. The term "figure" is abbreviated as "Fig." in the drawings.

[0054] The drawings show

[0055] Fig. 1 is a highly schematic representation of an elevator system according to the present disclosure;

[0056] Fig. 2a a front view of a car door in an elevator system according to Fig. 1; Fig. 2b a front view of a shaft door in an elevator system according to Fig. 1;

[0057] Fig. 3 is a schematic representation of a circuit diagram of a device from the state of the art.

[0058] Technology known safety circuit;

[0059] Fig. 4 shows a schematic representation of a circuit diagram of a safety circuit according to the present disclosure;

[0060] Fig. 5 is a diagram of a process according to the present disclosure.

[0061] Detailed description of the drawings

[0062] The described embodiments are merely examples that can be modified and / or supplemented in various ways within the scope of the claims. Each feature described for a particular embodiment can be used independently or in combination with other features in any other embodiment. Each feature described for an embodiment of a particular claim category can also be used accordingly in an embodiment of a different claim category.

[0063] Figure 1 shows an elevator system 1 with an elevator shaft 2, a first car 3.1, and a second car 3.2, both movable in the elevator shaft 2. The cars 3.1 and 3.2 each have a first car door 4.1 and a second car door 4.2, respectively, and are configured to stop at shaft doors 2.1, 2.2, 2.3, 2.4, 2.5, and 2.6 in landing positions 5.1, 5.2, 5.3, 5.4, 5.5, and 5.6 of a TD 41980 - 13 - October 2025

[0064] to be able to stop in the building in which the elevator system 1 is located. For example, in the illustration in Figure 1, the first car 3.1 stops at the fifth shaft door 2.5 and the second car 3.2 at the sixth shaft door 2.6. The cars 3.1, 3.2 are further driven by a simplified representation of a first drive device 6.1 and a second drive device 6.2, respectively, and by load-bearing elements 7.1, 7.2, for example, designed as suspension ropes or belts, which interact with the drive devices 6.1, 6.2. The cars 3.1, 3.2 are connected via the load-bearing elements 7.1, 7.2, for example, to counterweights (not shown in detail). The drive devices 6.1, 6.2 are, for example, electric machines and can only be operated if a safety circuit, which is explained in more detail below, is closed.

[0065] Figures 2a and 2b show the first car door 4.1 and a shaft door 2.5 in front view. Both the first car door 4.1 and the shaft door 2.5 each have two sliding door leaves and are shown in a slightly open position for illustrative purposes. A first contact element 8.1 of a first safety contact 8 is arranged on the right door leaf of the first car door 4.1, while a second contact element 8.2 of the safety contact 8 is arranged on the car 3.1 adjacent to the first car door 4.1. The safety contact 8 is closed when the first car door 4.1 is closed and the contact elements 8.1 and 8.2 are in contact with each other. In all other cases, the safety contact 8 is open. Similarly, a first contact element 9.1 is arranged on a door leaf at the shaft door 2.5, as is a second contact element 9.2 on a frame 10 of the shaft door 2.5, which together form a second safety contact 9.

[0066] Figures 3 and 4 each show partial views of safety circuits 12, 13 for the first car 3.1 at a shaft door 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, wherein the safety circuit 12 according to Figure 3 corresponds to the prior art and the safety circuit 13 according to Figure 4 to the present disclosure. The safety circuits 12, 13 are connected to the first drive device 6.1 such that the first drive device 6.1 can only be operated when the safety circuit 12, 13 is closed, and each has the safety contacts 8, 9 connected in series, wherein each safety contact 8, 9 refers, here purely by way of example, to a safety contact 8', 9' of a front of the first car door 4.1 or the shaft door 2.5 and a TD 41980 - 14 - October 2025

[0067] The safety contacts 8", 9" are located on the rear side of the first car door 4.1 or the shaft door 2.5. The safety contacts 8', 9' and 8", 9" are redundant to each other. Furthermore, the safety circuits 12, 13 include a first signal pickup 14.1 located between the first safety contact 8 and the second safety contact 9, and a second signal pickup 14.2 located downstream of the second safety contact 9. The signal pickups 14.1, 14.2 allow verification of whether a signal, such as an electrical voltage, is present at the respective points of the safety circuits 12, 13. A signal is present only if there is a closed connection via the safety contacts 8, 9 to a signal-conducting section of the safety circuits 12, 13. The signal pickups 14.1, 14.2 thus allow conclusions to be drawn about the closed state of the safety contacts 8, 9.

[0068] The safety circuits 12 and 13 also include a bypass 16, which comprises two redundant bypass switches 16.1 and 16.2, is connected in parallel to the safety contacts 8 and 9, and can be switched, for example, by a relay (not shown in detail here) and / or includes a transceiver (also not shown in detail) for detecting conditions for closing the bypass 16. Such conditions include, for example, a low speed of the first car 3.1 below a limit value and / or a position of the first car 3.1 in the immediate vicinity of the shaft door 2.1, 2.2, 2.3, 2.4, 2.5, or 2.6.

[0069] If safety circuit 12 detects that the first car 3.1, while approaching a landing position 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, is in the vicinity of one of the shaft doors 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 and is only moving at a low speed, the bypass 16 is closed, and the first drive unit 6.1 can continue to operate for the remaining approach and to compensate for any fluctuations, while the doors 4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 are already being opened or are already open. However, to determine the closed state of the second safety contact 9, the bypass 16 must be opened so that no signal is present at the second signal pickup 14.2 via the bypass. The first drive unit 6.1 can only be operated again for journey preparations when both safety contacts 8 and 9, and thus the safety circuit 12, are closed. TD 41980 - 15 - October 2025

[0070] In the safety circuit 13, according to the present disclosure, a disconnect switch 18 is further arranged downstream of the second safety contact 9 and upstream of the return path 19 of the bridging 16 to the safety circuit 13. The disconnect switch 18 is, for example, designed as a relay and configured to open when a signal is present at the first signal pickup 14.1. When the disconnect switch 18 is open, the return path 19 of the bridging 16 is disconnected from the second signal pickup 14.2, so that the presence of a signal at the second signal pickup depends solely on the closed state of the second safety contact 9 or on both safety contacts 8 and 9. The bridging 16 can then remain closed to operate the first drive device 6.1, while the closing status of the doors 4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 can be checked via the signal acceptances 14.1, 14.2 independently of the bridging 16.In this way, the closing of doors 4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 can take place in parallel with the preparations for travel of the first drive device 6.1 or the first car 3.1, so that the time required to make preparations for travel after the closing of doors 4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 is eliminated.

[0071] Figure 5 shows a process flow diagram of a method 30 for operating an elevator system 1 when a journey begins with an open first car door 4.1, an open shaft door 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 and a closed bypass 16 according to the present disclosure. In an optional first step 31, the door 4.1 associated with the safety contact 8 arranged in series before the other is closed. In a second step 32, the disconnect switch 18 is opened. In a third step 33, travel preparations are carried out for the first drive unit 6.1 and / or the first car 3.1 with the bypass 16 closed and the disconnect switch 18 open. In a fourth step 34, all remaining open doors 4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 are closed. Therefore, if the first car door 4.1 is already closed, the shaft door 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 is also closed.6 or, if the first car door 4.1 is still open, the first car door 4.1 and the shaft doors 2.1, 2.2, 2.3, 2.4, 2.5, 2.6 are closed. The third step 33 and the fourth step 34 may overlap in time.

[0072] In a fifth step 35, the disconnect switch 18 is closed. In a sixth step 36, the bypass 16 is opened. The fifth step 35 and the sixth step 36 can occur in any order, overlapping and / or simultaneously. In an optional seventh step 37, on which the fifth step 35 optionally depends, the start of travel of the second car 3.2, which is traveling in front of the first car 3.1, is detected, whereby the disconnect switch 18 is only closed in the fifth step 35 once the start of travel of the second car 3.2 has been detected. In an eighth step 38, travel of the first car 3.1 begins.

[0073] TD 41980 - 17 - October 2025

[0074] Reference symbol list

[0075] 1 elevator system

[0076] 2 elevator shafts

[0077] 2.1 First shaft door of the elevator shaft

[0078] 2.2 Second shaft door of the elevator shaft

[0079] 2.3 Third shaft door of the elevator shaft

[0080] 2.4 fourth shaft door of the elevator shaft

[0081] 2.5 fifth shaft door of the elevator shaft

[0082] 2.6 sixth shaft door of the elevator shaft

[0083] 3.1 First carriage

[0084] 3.2 second passenger basket

[0085] 4.1 First car door (car door of the first car)

[0086] 4.2 Second car door (car door of the second car)

[0087] 5.1 First landing position

[0088] 5.2 Second landing position

[0089] 5.3 Third landing position

[0090] 5.4 fourth landing position

[0091] 5.5 fifth landing position

[0092] 5.6 sixth landing position

[0093] 6.1 First drive device (drive device of the first elevator car)

[0094] 6.2 Second drive device (drive device of the second elevator car)

[0095] 7.1 First lifting element (lifting element of the first car)

[0096] 7.2 Second lifting device (lifting device of the second car)

[0097] 8 first safety contact

[0098] 8' Safety contact of a front side, forming the first safety contact

[0099] 8" safety contact on one back side, forming the first safety contact

[0100] 8.1 First contact element of the first safety contact

[0101] 8.2 second contact element of the first safety contact

[0102] 9 second safety contact

[0103] 9' Safety contact of one front side, forming the second safety contact

[0104] 9' ' Safety contact on one reverse side, forming the second safety contact

[0105] 9.1 First contact element of the second safety contact TD 41980 - 18 - October 2025

[0106] 9.2 Second contact element of the second safety contact

[0107] 10. Frame of the shaft door

[0108] 12 safety circuits according to the state of the art

[0109] 13 Security circle according to the present disclosure

[0110] 14.1 First signal acceptance

[0111] 14.2 Second signal acceptance

[0112] 16 Bridging

[0113] 16.1 First bypass switch of the bypass

[0114] 16.2 Second bypass switch of the bypass

[0115] 18 disconnect switches

[0116] 19 Return of the bridging to the safety circuit

[0117] 30 methods for operating an elevator system

[0118] 31 First step - optional: closing a first door

[0119] 32 Second step - Opening the disconnect switch

[0120] 33 Third step - Carrying out journey preparations

[0121] 34 Fourth step - Closing all remaining open doors

[0122] 35 fifth step - closing the disconnect switch

[0123] 36 sixth step - Opening the bridge

[0124] 37 seventh step - Recording the start of a journey for the second car

[0125] 38 eighth step - beginning of the journey of the first car

Claims

TD 41980 - 19 - October 2025 Claims 1. Elevator system (1) comprising an elevator shaft (2) with a shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6); a first car (3.1) movable along the elevator shaft (2) with a first car door (4.1); and a first drive device (6.1) for driving the first car (3.1); wherein the first car door (4.1) has a first safety contact (8) which makes contact when the first car door (4.1) is closed and the shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6) has a second safety contact (9) which makes contact when the shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6) is closed; wherein the first safety contact (8) and the second safety contact (9) are connected in series in a safety circuit (13); wherein the safety circuit (13) is designed such that operation of the first drive device (6.1) is only possible when the safety circuit (13) is closed; and wherein the safety circuit (13) has a switchable bridging (16) of the first safety contact (8) and the second safety contact (9); characterized in that the safety circuit (13) has a disconnect switch (18) behind both safety contacts (8, 9) and before a return (19) of the bridging (16) to the safety circuit (13).

2. Elevator system (1) according to claim 1, wherein the switchable bridging (16) comprises a transceiver, in particular an SR module.

3. Elevator system (1) according to claim 2, wherein the transceiver is configured to close the bridging (16) when the first car (3.1) is positioned in the vicinity of the shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6) and below a limit speed of the first car (3.1).

4. Elevator system (1) according to one of the preceding claims, wherein the disconnect switch (18) is designed as a relay. TD 41980 - 20 - October 2025 5. Elevator system (1) according to one of the preceding claims, wherein the elevator system (1) is configured to open the disconnect switch (18) when the first safety contact (8) in the series circuit is closed.

6. Elevator system (1) according to one of the preceding claims, wherein a first signal pickup (14.1) is arranged between the safety contacts (8, 9) connected in series, wherein the safety circuit (13) is configured to open the disconnect switch (18) depending on the signal received at the first signal pickup (14.1).

7. Elevator system (1) according to one of the preceding claims, wherein a second signal pickup (14.2) is arranged between the rear of the two safety contacts (8, 9) and the disconnect switch (18), wherein the safety circuit (13) is configured to close the disconnect switch (18) depending on the signal received at the second signal pickup (14.2).

8. Elevator system (1) according to one of the preceding claims, wherein the first safety contact (8) is arranged in series before the second safety contact (9).

9. Elevator system (1) according to one of the preceding claims, further comprising a second car (3.2) movable along the elevator shaft (2) with a second car door (4.2); and a second drive device (6.2) for driving the second car (3.2); wherein the elevator system (1) is configured such that one of the two cars (3.1, 3.2) moving behind the other car (3.1, 3.2) is operated at a reduced speed, a reduced acceleration and / or a reduced rate of change of acceleration.

10. Method (30) for operating an elevator system (1) according to one of the preceding claims at the start of a journey from an open first car door (4.1), an open shaft door (2.1, 2.2, 2.3, 2.4, 2.5, 2.6) and a closed bridging (16), comprising the steps: TD 41980 - 21 - October 2025 optional closing (31) of the door (4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6) assigned to the safety contact (8, 9) arranged in series before the other; Opening (32) of the disconnect switch (18); Exports (33) of travel preparations of the first drive device (6.1) and / or the first car (3.1) with the bypass closed (16) and the disconnect switch open (18); Close (34) all doors that are still open (4.1, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6); Closing (35) of the disconnect switch (18); Opening (36) of the bridge (16); Beginning (38) the journey of the first car (3.1).

11. Method (30) according to claim 10, wherein performing travel preparations of the first drive device (6.1) and / or the first car (3.1) comprises switching on contactors of the first drive device (6.1), charging an intermediate circuit of the first drive device (6.1) and / or opening a brake of the first car (3.1).

12. Method (30) according to one of claims 10 or 11, wherein the opening of the disconnect switch (18) is dependent on the signal received at the first signal pickup (14.1). 13 Method (30) according to one of claims 10 to 12, wherein the closing of the disconnect switch (18) is dependent on the signal taken at the second signal pickup (14.2).

14. Method (30) according to one of claims 10 to 13 for operating an elevator system (1) according to claim 9 with a simultaneous start of travel of both elevator cars (3.1, 3.2), wherein the travel of the elevator car (3.1, 3.2) traveling behind the other elevator car (3.1, 3.2) only begins with or after the start of travel of the other elevator car (3.1, 3.2).

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