BRAKING SYSTEM FOR AN ELEVATOR

Description

[0001] The present invention relates to a braking system, a traveling body component, an elevator system and a method for constructing and operating the braking system.

[0002] In an elevator system, a traveling body is typically moved vertically along a travel path between different floors or levels within a building. At least in tall buildings, a type of elevator is usually used in which the traveling body is held by rope- or belt-like suspension elements and is moved within an elevator shaft by moving the suspension elements using a drive motor. Alternatively, a suspension element can also be designed as a direct drive for the car, for example, by a friction wheel on a rail or by a linear drive. In order to at least partially compensate for the load of the traveling body to be moved by the drive motor, a counterweight is usually attached to an opposite end of the suspension element.In order to be able to hold the car on a floor without keeping the drive switched on or to hold the car in case the drive or the support mechanism fails, the elevator system has a braking system.

[0003] DE 10 2014 111 359 A1 shows that a car brake unit is provided with at least one, preferably several, hydraulic actuators, and that this is arranged on the car, i.e., an elevator cabin. DE 10 2014 111359 A1 discloses the preamble of claim 1.

[0004] Such braking systems have a limited service life. In particular, the brake pads wear out during operation. The braking system is usually designed so that the failure of one brake does not result in the failure of the entire braking system. The failure of one brake pad should therefore not cause the vehicle to crash in free fall. Because the brakes are less effective, the braking distance is longer. The longer braking distance means that more potential energy is released in the vehicle. This means that the remaining brakes have to absorb more energy. However, because when one brake pad reaches the end of its service life, the service life of the brake pads of the other brakes is also almost reached, they are no longer able to absorb the additional energy. There is then a risk that the failure of an individual brake pad will cause the other brake pads to fail in an emergency situation.This would mean that the brakes would no longer safely stop and hold the elevator car. Such a braking system would therefore no longer safely protect the elevator system and its passengers against the car falling.

[0005] It can therefore be seen as a task to make such a braking system safer.

[0006] According to a first aspect of the invention, a braking system for an elevator system solves the problem. The braking system comprises a first braking circuit, a second braking circuit, and a control unit. The first braking circuit and the second braking circuit each comprise a brake, and each brake comprises an actuator and a main spring unit. The actuator is preloaded by the main spring unit in the closing direction of the brake with the force required to apply the braking force. The actuator, activated by a control signal from the control unit, compensates for the force of the main spring unit, and the actuator thereby releases the brake. The control unit generates a first control signal for the first braking circuit and a second control signal for the second braking circuit. The control unit activates neither of the two control signals, only the first of the two control signals, only the second of the two control signals, or both control signals.When activating only one of the two control signals, the control unit selects between the activation of the first control signal and the activation of the second control signal such that the ratio of the number of activations of the first brake circuit and the number of activations of the second brake circuit strives for a specified ratio.

[0007] According to a second aspect of the invention, a vehicle body component with a braking system according to the first aspect of the invention achieves the object. The first braking circuit, the second braking circuit, and the control unit are attached to the vehicle body component for transport.

[0008] According to a third aspect of the invention, a vehicle with a braking system according to the first aspect of the invention or with a vehicle component according to the second aspect of the invention achieves this objective. The first braking circuit comprises a first brake and a second brake, and the first brake and the second brake are mounted on opposite sides of the vehicle. In particular, the second braking circuit comprises a third brake and a fourth brake, and the third brake and the fourth brake are mounted on opposite sides of the vehicle.

[0009] According to a fourth aspect of the invention, an elevator system with a braking system according to the first aspect of the invention or a traveling body according to the third aspect of the invention solves the problem. The elevator system has at least a first and a second rail system, wherein one of the two brakes of a braking circuit brakes on the first rail system, and the other of the two brakes of the same braking circuit brakes on the second rail system.

[0010] According to a fifth aspect of the invention, a method for constructing a vehicle according to the fourth aspect of the invention solves the problem. The method for constructing a vehicle with a braking system includes the steps: Attaching the first brake circuit and the associated brakes and the second brake circuit and the associated brakes and the control unit to a chassis component, assembling the chassis component with other components of the chassis to form an at least partially assembled chassis, transferring the brakes from the chassis component to one of the other components of the chassis.

[0011] According to a sixth aspect of the invention, a method for operating a braking system according to the first aspect of the invention solves the problem. The method for operating a braking system comprises the steps: Receipt or generation of a command to activate only one brake circuit by the control unit, selection of the brake circuit to be activated, activation of the selected brake circuit.

[0012] Possible features and advantages of embodiments of the invention may be considered, among other things and without limiting the invention, to be based on ideas and findings described below.

[0013] A braking system can be used to catch a traveling body. This means that if excessive speed is detected, the braking system brakes with an acceptable deceleration until it comes to a stop and then safely holds the traveling body in this position. A deceleration can be considered acceptable if the acceleration that occurs remains so small that neither people are injured nor the elevator system is damaged. Another function of the braking system can be to safely stop the traveling body on a floor after it has reached that floor and hold it there. In this process, the driving body is first stopped in the correct position by the drive. The traveling body essentially comes to a standstill there. At least some of the brakes of the braking system are then activated and hold the traveling body in this position so that the drive can be switched off.Furthermore, the braking system can also be used to slow down when entering a floor.

[0014] The braking system comprises several brake circuits, each with at least a first and a second brake. The brake comprises a main spring unit. The main spring unit can be designed as a steel spring or a gas pressure cylinder. Combinations of several steel springs and / or gas pressure cylinders can also form the main spring unit. The main spring unit serves to preload the brake in a closing direction such that a sufficient braking force is generated so that the brake can brake as required. The actuator serves to open the brake against the force of the main spring unit.

[0015] The braking system is usually activated to keep the elevator car on a floor. This braking system is activated every time the elevator system travels.

[0016] The control unit is capable of receiving a command to activate the brakes. Such a command can reach the control unit, for example, via a bus system. Such a command can contain the instruction to activate one brake circuit, two brake circuits, or all brake circuits. The control unit preferably has a microprocessor to receive and process the command. Alternatively, the control unit can also generate such a command itself. For this purpose, the control unit can, for example, evaluate other system data from the elevator system. This could be, for example, the speed or acceleration of the traveling body, a status of the safety circuit, or a load measurement in the traveling body. This means that the signals from other sensors can be processed on the control unit's microprocessor. One result of such processing could also be a command to activate the brakes, and in particular an individual brake circuit.

[0017] The control unit processes the command and decides which of the brake circuits are activated. The control unit has the option of selectively controlling the brakes of the individual brake circuits in the form of control signals. For example, the control signal can be the drop in electrical voltage on a cable that connects a brake circuit, whereby the drop in voltage is capable of deactivating the actuators designed as lifting magnets, and the brakes of this brake circuit are thereby closed. Alternatively, the control signal can also be an electrical voltage that controls electromagnetic valves of a hydraulic system, whereby the pressure can be released from a hydraulic circuit and the brakes are thereby closed. The control unit is preferably defined in such a way that the control of the valves is still seen as an internal function of the control unit.The control signal transmitted to the brake circuit is then the pressure of the hydraulic fluid in the brake circuit. An increase in pressure in the hydraulic lines of a brake circuit releases the brakes. A drop in pressure causes them to reapply.

[0018] The control unit typically receives the command to release all brake circuits before a journey. The vehicle is then moved.

[0019] Emergency stop situations can occur during travel, such as a power outage or the detection of a critical sensor failure. Power outages, in particular, can occur very frequently in certain regions, which means that emergency stop situations caused by a power outage can also become very common. The breaking of a support element can also be such an emergency stop situation. At least in the initial phase, it can be advantageous to brake with only one brake circuit to minimize deceleration. Even if the vehicle only needs to be stopped briefly for a stop on a floor, it can be advantageous to close only one of the brake circuits.

[0020] If an emergency stop situation occurs during the journey, or the elevator body is only required to stop briefly on a floor, the control unit receives a command from the elevator control system, which has detected the emergency stop situation, to brake using one of the brake circuits. Braking with only one brake circuit is advantageous in order to limit deceleration. If braking were always carried out with the same brake circuit in these cases, it would wear out very quickly. It is therefore advantageous to brake occasionally with one of the other brake circuits. For this reason, the control unit selects a brake circuit in cases where it could activate more brake circuits than are currently necessary. The control unit has a decision algorithm that makes this selection.

[0021] It is advantageous to have multiple brake circuits, but to activate only one of them when stopping at a landing, thus protecting the others. Using two brake circuits nearly doubles the service life of the brake pads. A braking system can also include more than two brake circuits.

[0022] The brakes of the individual brake circuits are each controlled by a control signal from the control unit. The control signal therefore originates in the control unit. This control signal preferably contains sufficient energy, i.e. the ability to perform work, to supply the actuator with enough energy to overcome the preload force of the main spring unit. The control signal can therefore be a pressure increase in a hydraulic line that moves a hydraulic actuator against the preload force of the main spring unit. Alternatively, the control signal can be an electrical power supply that supplies current to an electromagnet so that it moves against the preload force of the main spring unit.

[0023] However, it has now been recognized that with an even distribution of activations across both brake circuits, both brakes reach their end of life at approximately the same time. This poses the risk that the braking system may no longer be able to brake sufficiently at this point in time if an emergency stop situation occurs that requires the application of large braking forces and the absorption of large amounts of braking energy.

[0024] It is therefore proposed to control the selection of brakes so that the brakes of the first brake circuit age faster than those of the second brake circuit. Thus, in an emergency stop situation, even if the brakes of the first brake circuit are nearing the end of their service life, the brakes of the second brake circuit are still sufficiently far from their end of life. This makes the braking system more reliable against crashes.

[0025] The traveling body component can be designed in the form of a roof element of the elevator car. The control unit is already pre-assembled on the traveling body component. The brakes are also already attached to this traveling body component, even if this position does not correspond to the final position in the elevator system. Particularly with hydraulic brakes, it is advantageous that all connections to the brakes are firmly connected in the factory. This allows the connections to be permanently leak-free. The brakes are then only repositioned during assembly of the traveling body. The hydraulic lines, in particular, are designed to be flexible for this purpose. The advantage is that the braking system is assembled in the factory by a specialist. On the construction site, only the brakes need to be repositioned. This increases the quality of the assembly.Nevertheless, the brake can easily be transported as part of the chassis component along with the other parts.

[0026] On site, the chassis component can then be assembled with other components to form a chassis. During assembly, the brakes, which were attached to the chassis component during transport, can be moved to a location on the side of the chassis. Especially when hydraulic brakes are used, the hoses are designed to be flexible, allowing them to be installed on site without opening the fluid-carrying components.

[0027] Typically, a bogie is guided by two rail systems, which also serve as brake rails. A single rail system here refers to a single line, preferably consisting of adjacent rail elements. These rail systems run on opposite sides of the bogie. The brakes are mounted on opposite sides of the bogie so that they can engage and brake against the rail systems.

[0028] The method for operating the braking system responds to the receipt or generation of an activation command. Such a command can be received, for example, via a bus system for data communication. The braking system can also have sensors such as speed sensors and / or acceleration sensors that allow the braking system to decide when activation is appropriate. The command includes an indication of whether only one brake circuit or several brake circuits are to be activated. In this case, only one brake circuit, or a subgroup of all available brake circuits, is to be activated. The braking system selects which of the available brake circuits is selected. This brake circuit is then selected in such a way that the ratio of the number of activations of the first brake circuit to the number of activations of the second brake circuit strives for a specified ratio.

[0029] According to a preferred embodiment of the braking system, the braking system, and in particular the control unit, has a memory system that stores at least one state variable that, when only one braking circuit of the braking system is activated, is passed as a parameter to a decision algorithm that selects the control signal to be activated.

[0030] Depending on which of the following methods is used, the unit preferably stores at least a base for a random number or a position in a sequence and the sequence. The storage unit preferably also stores further data, such as the executable code of the decision algorithm.

[0031] According to a further embodiment of the method for operating a braking system, the selection of the braking circuit to be activated comprises the steps: Generation of a random number Selection of the brake circuit to be activated based on the random number, whereby the probability of activating a brake circuit is selected so that the specified ratio results.

[0032] The generation of a random number preferably involves passing an initial value from one call of the random number generator to the next. This can be stored in the memory system.

[0033] A random number between 0 and 1, for example, can be generated. If the random number is smaller than a certain value, the first brake circuit is activated. Otherwise, the second brake circuit is activated.

[0034] According to a preferred embodiment of the method for operating a braking system, the selection of the braking circuit to be activated comprises the steps: Defining a sequence of individual activations of the first or second brake circuit, the sequence including the activations of the first or second brake circuit in the defined ratio, Defining an indicator for a position in the sequence, Selecting the brake circuit to be activated from the sequence based on the indicator, Setting the indicator to the next position in the sequence, or Setting the indicator to the first position in the sequence if the indicator is set to the last position in the sequence.

[0035] For example, let's say you want a fixed ratio of 1.5 for the number of activations of the first brake circuit to the number of activations of the second brake circuit. This can be achieved with a sequence that activates the first brake circuit three times, then activates the second brake circuit twice, and then starts again from the beginning. The memory system stores the position of the braking system, i.e., the decision algorithm, in the sequence. This value is incremented by one after each activation and reset to the beginning after the entire sequence has been run through.

[0036] According to a preferred embodiment of the method for operating a braking system, the method further comprises one or more of the steps: Catching a traveling body by the braking system in response to the detection of an overspeed of the traveling body, holding the traveling body on a floor with the drive switched off, braking and safely holding the traveling body in an emergency stop situation, in particular in the emergency stop situations of a power failure, opening of a shaft door during a journey or detection of faulty measuring signals.

[0037] A braking system can be used to catch a vehicle. If excessive speed is detected, the braking system brakes with a reasonable deceleration until it comes to a stop, and then safely holds the vehicle in this position. Preferably, only one brake circuit is activated initially to minimize deceleration. Only after the vehicle has come to a stop are all brake circuits closed. This is advantageous because keeping the brakes open typically consumes energy.

[0038] Another function of the braking system may be to safely stop the vehicle on a floor after reaching that floor and hold it there. Preferably, only one brake circuit is activated for this purpose. Only during longer stops on a floor is it advantageous to close the brakes of all brake circuits to save energy.

[0039] A braking system can be used to decelerate and hold a vehicle in an emergency stop situation. Preferably, only one brake circuit is initially activated to minimize deceleration. Only after stopping are all brake circuits closed. This is advantageous because keeping the brakes open typically consumes energy.

[0040] According to a preferred embodiment of the braking system, the actuator is designed as a hydraulic cylinder, and a flow of hydraulic fluid acts as a control signal.

[0041] In other words, the actuators in the brakes are designed as hydraulic cylinders. Applying pressure to the hydraulic line connecting the control unit to the brake moves a piston in the brake housing. This movement counteracts the main spring unit, thereby releasing the brake.

[0042] According to a preferred embodiment of the braking system, the hydraulic cylinder has a piston, wherein the piston is actuated by the hydraulic fluid from only one side.

[0043] This has the advantage that only one hydraulic line needs to be routed to a brake. This is cheaper to manufacture and install.

[0044] According to a preferred embodiment of the braking system, each of the brakes has a plurality of hydraulic cylinders, each with its own piston in a common housing.

[0045] This multitude of pistons can transfer force more evenly to the brake pad. Furthermore, several smaller cylinders and pistons are cheaper to produce than one large piston.

[0046] According to a preferred embodiment of the braking system, a braking circuit comprises two brakes.

[0047] It is advantageous that at least one first brake and one second brake of one of the first and second brake circuits are arranged on opposite sides of the vehicle body. The resulting force generated when a brake circuit is activated acts closer to the center of gravity of the cabin than if all brakes of a brake circuit were acting on the same side of the cabin.

[0048] According to a preferred embodiment of the braking system, the predetermined ratio is between 20 to 1 and 1.01 to 1, preferably it is between 9 to 1 and 1.1 to 1, more preferably it is between 6 to 1 and 2.5 to 1, and most preferably the ratio is 4 to 1.

[0049] It is advantageous for one brake circuit to be activated slightly more often than the other, as this allows the more frequently activated brake circuit to detect when it has reached its intended service life, while the other brake circuit still has safety reserves because it has been activated less often. Ideally, one brake, i.e. its brake shoe, is activated four times more often than the other brake, i.e. its brake shoe. This means that the brake shoe that is activated less often has reached approximately 25% (=1 / 4) of its service life. In this situation, it is still sufficiently safe to be able to withstand very heavy loads. Depending on the safety requirements and the choice of material for the brake pads, other ratios within the ranges specified above may also prove advantageous.

[0050] Further advantages, features, and details of the invention will become apparent from the following description of exemplary embodiments and from the drawings, in which identical or functionally equivalent elements are provided with identical reference numerals. The drawings are merely schematic and not to scale.

[0051] Showing: Fig. 1 an elevator system with the braking system, Fig. 2 a hydraulic circuit diagram of the braking system, Fig. 3 a brake, Fig. 4 a braking system on a traveling body, Fig. 5 a traveling body component, Fig. 6 a course of the aiming of a ratio.

[0052] Fig. 1 shows an elevator system 100 with a braking system 10. The elevator system 100 has a drive 101 and a traveling body 60 suspended from support means 63. The traveling body 60 has a braking system 10. The braking system 10 has a control unit 13 and a total of four brakes 20. A first brake 41 is arranged on a first braking circuit 11 and a second brake 42 is arranged on a first braking circuit 11. In addition, a third brake 43 is arranged on a second braking circuit 12 and a fourth brake 44 is arranged on a second braking circuit 12. All brakes 20 act on a rail system 70. The first brakes of a braking circuit 41, 43 act on the first rail system 71. The second brakes of a braking circuit act on the second rail system 72. The braking system 10 can be hydraulic.

[0053] Fig. 2 shows a diagram of a hydraulic braking system as used in Fig. 1 is shown.

[0054] In addition to the electronic and electrical components not shown, the control unit includes a tank 112, a pump 115, two check valves 114, two electromagnetic valves 113, and a pressure relief valve 111. The two hydraulic lines 32 connect the control unit to the brakes 20, i.e., 41, 42, 43, and 44.

[0055] The pump 115 continuously pumps the hydraulic fluid 31. Both brake circuits 11 and 12 are each supplied with hydraulic fluid 31 via a check valve 114. To keep the brake closed, the electromagnetic valve 113 of the corresponding brake circuit 11 or 12 can drain the hydraulic fluid 31 directly into a tank 112. As a result, no pressure builds up in the brake circuits 11 or 12, and the brakes 20 remain closed. To close the electromagnetic valve 113, a voltage must be applied to the electromagnetic valve 113. This closes the electromagnetic valve 113 and hydraulic pressure builds up in the corresponding brake circuit, opening the brake 20. The hydraulic fluid presses on a piston 33 in a cylinder 30 as actuator 21. The build-up of pressure causes the brake 20 to be released and held released, contrary to the main spring unit 22.A pressure relief valve 111 ensures that a maximum permissible pressure in the hydraulic lines 32 is not exceeded, even if both electromagnetic valves 113 are set so that no hydraulic fluid 31 is drained into the tank 112. In this case, the hydraulic fluid 31 flows into the tank 112 via the safety valve 111.

[0056] The brake pads 35 close in the closing direction 29 and thereby press on parts of the rail systems not shown here.

[0057] During travel, the electromagnetic valves 113 are closed, allowing the hydraulic fluid 31 to release the brakes 20. After receiving or generating a command to activate only one brake circuit 11 or 12, the decision algorithm selects one of the brake circuits 11 or 12. As an example, the first brake circuit 11 is selected here. The electromagnetic valve 113 on the first brake circuit 11 is now opened, releasing pressure from the first brake circuit 11. The brakes 41 and 42 close and begin braking. The pressure in the second brake circuit 12 is maintained due to the check valve 114. Therefore, the brakes 43 and 44 remain in a released state.

[0058] Fig. 3 shows the traveling body of the elevator system from the Fig. 1 . The hydraulic lines 32 connect the control unit 13 to the brakes 20. Separate hydraulic lines 32 run for the first brake circuit 11 and the second brake circuit 2.

[0059] As in the previous figures, a first brake is arranged on the first brake circuit 41 and a second brake on the first brake circuit 42. Furthermore, a first brake is arranged on the second brake circuit 43 and a second brake on the second brake circuit 44.

[0060] A chassis component 61 is shaped as a roof. Fig. 4 shows the chassis component as it is delivered to the construction site. The control unit 13, the hydraulic lines 32 and the brakes 20 are attached to the chassis component 61. A roof element, as in Fig. 3 und 4 shown, is particularly well suited as a chassis component 61 for safely transporting the braking system 10 to the construction site. At the construction site, the roof is then assembled with the other components of the chassis, and the brakes 20 are moved from their transport position on the chassis component 61 to their deployment position. The deployment positions are preferably arranged laterally next to the chassis 60, preferably on opposite sides of the chassis.

[0061] Fig. 5shows a curve of the ratio of the number of activations of the first brake circuit to the number of activations of the second brake circuit, aiming for a specified ratio. The value of the ratio is plotted on the y-axis. The x-axis runs over the total number of activations. As the number of activations increases, the ratio 50 moves ever closer to a specified target ratio 51. At the beginning, the deviations A from the target ratio can still be large. As the number of activations x increases, these deviations B become increasingly smaller.

[0062] Finally, it should be noted that terms such as "having," "comprising," etc., do not exclude other elements or steps, and terms such as "a" or "an" do not exclude a plurality. Furthermore, it should be noted that features or steps described with reference to one of the above embodiments may also be used in combination with other features or steps of other embodiments described above. Reference signs in the claims are not to be considered as limitations.

Claims

1. Brake system (10) for an elevator system, comprising a first brake circuit (11), a second brake circuit (12) and a control unit (13), the first (11) and second brake circuits (12) each comprising a brake (20, 41, 42, 43, 44), and each brake (20, 41, 42, 43, 44) comprising an actuator (21) and a main spring unit (22), the actuator (21) being preloaded by the main spring unit (22) in the closing direction (29) of the brake (20, 41, 42, 43, 44), with the force required for the application of the braking force, and the actuator (21) being activated by a control signal of the control unit (13), compensating the force of the main spring unit (22), and thereby releasing the brake (20, 41, 42, 43, 44), the control unit (13) generating a first control signal for the first brake circuit (11) and a second control signal for the second brake circuit (12), the control unit (13) activating neither of the two control signals, only the first of the two control signals, only the second of the two control signals, or both control signals, characterized in that, upon activation, the control unit (13) selects only one of the two control signals between the activation of the first control signal and the activation of the second control signal, such that the ratio (50) of the number of activations of the first brake circuit and the number of activations of the second brake circuit aims at a fixed ratio (51).

2. Brake system (10) according to claim 1, characterized in that the brake system (10), in particular the control unit (13), has a memory system which stores at least one state variable, which, upon activation of only one brake circuit (11, 12), is transferred as a parameter to a decision algorithm that makes the selection of the control signal to be activated.

3. Brake system (10) according to either claim 1 or claim 2, characterized in that the actuator (21) is designed as a hydraulic cylinder (30), and in that a flow of a hydraulic fluid (31) acts as the control signal.

4. Brake system (10) according to any of the preceding claims, characterized in that a brake circuit (11, 12) comprises two brakes (20, 41, 42, 43, 44).

5. Brake system (10) according to any of the preceding claims, characterized in that the fixed ratio (51) is between 20 to 1 and 1.01 to 1, preferably between 9 to 1 and 1.1 to 1, particularly preferably between 6 to 1 and 2.5 to 1, and most preferably the fixed ratio (51) is 4 to 1.

6. Brake system according to claim 3, characterized in that the hydraulic cylinder (30) has a piston (33), the piston being actuated only from one side by the hydraulic fluid (31).

7. Brake system according to claim 6, characterized in that each of the brakes (20, 41, 42, 43, 44) has a plurality of hydraulic cylinders (30), each having a separate piston (33) in a common housing (34).

8. Travel member component (61) comprising a brake system (10) according to any of the preceding claims, characterized in that the first brake circuit (11), the second brake circuit (12), and the control unit (13) are fastened to the travel member component (61) for transport.

9. Travel member (60) comprising a brake system (10) or a travel member component (61) according to any of the preceding claims, characterized in that the first brake circuit (11) comprises a first brake (41) and a second brake (42), and the first brake (41) and the second brake (42) are attached on opposite sides of the travel member (60), in particular, the second brake circuit (12) comprises a third brake (43) and a fourth brake (44), and the third brake (43) and the fourth brake (44) are attached on opposite sides of the travel member (60).

10. Elevator system comprising a brake system (10) according to any of claims 1 to 7 or a travel member (60) according to claim 9, characterized in that the elevator system (100) has at least a first (71) and a second (72) rail system (70, 71, 72), in each case one of the two brakes (20, 41, 42, 43, 44) of a brake circuit (11, 12) braking on the first rail system (71), and in each case the other of the two brakes (20, 41, 42, 43, 44) of the same brake circuit braking on the second rail system (72).

11. Method for constructing a travel member (60) comprising a brake system (10) according to claim 9, comprising the steps of: - attaching the first brake circuit (11) and the associated brakes (20, 41, 42), and the second brake circuit (12) and the associated brakes (20, 43, 44), and the control unit (13), to a travel member component (61), - assembling the travel member component (61) together with further components of the travel member (60) to form an at least partially mounted travel member, - transferring the braking from the travel member component (61) to one of the further components of the travel member (60).

12. Method for operating a brake system (10) according to any of claims 1 to 7, comprising the steps of: - receiving or generating a command for activating only one brake circuit (11, 12), by the control unit (13), - selecting the brake circuit (11, 12) to be activated, - activating the selected brake circuit (11, 12).

13. Method according to claim 12, characterized in that the selection of the brake circuit (11, 12) to be activated comprises the steps of: - generating a random number - selecting the brake circuit (11, 12) to be activated on the basis of the random number, the probability for activation of a brake circuit (11, 12) being selected such that the fixed ratio results.

14. Method according to claim 12, characterized in that the selection of the brake circuit (11, 12) to be activated comprises the steps of: - determining a sequence of individual activations of the first (11) or second (12) brake circuits (11, 12), the sequence including the activations of the first or second brake circuit (11, 12) in the fixed ratio (51), - determining an indicator for a position in the sequence, - selecting the brake circuit (11, 12) to be activated from the sequence, based on the indicator, - setting the indicator to the next position in the sequence, or setting the indicator to the first position in the sequence if the indicator is set to the last position of the sequence.

15. Method according to any of claims 12 to 14, further comprising one or more of the steps of: - catching a travel member (60) by the brake system (10) in response to the detection of an overspeed of the travel member (60), - holding the travel member (60) at a floor when the drive (101) is switched off - braking and secure holding of the travel member (60) in an emergency stop situation, in particular in the event of emergency stop situations due to a power failure, opening of a shaft door during travel, or detection of incorrect measurement signals.