An arrangement for preventing access to an elevator shaft

Abstract

Elevator shafts commonly have a pit in the bottom of the elevator shaft. Access to the elevator shaft and particularly to this pit is prevented by using an arrangement that detects that the elevator is on a floor and prevents moving of the elevator car from the floor when the landing door is still open. The arrangement improves the safety of the maintenance personnel as they cannot access the elevator shaft and particularly the pit, wherein they would in at a risk of crushing under the elevator car.

Description

[0001] AN ARRANGEMENT FOR PREVENTING ACCESS TO AN ELEVATOR SHAFT

[0002] DESCRIPTION OF BACKGROUND

[0003] The following disclosure relates to elevators and particularly to improving safety related features of an elevator . More particularly the disclosure relates to improved safety features with respect to the maintenance of the elevator .

[0004] Modern elevators comprise an elevator car traveling in an elevator shaft . The elevator shaft is not accessible to the passengers . Some of the elevator components are located in elevator shafts and may require inspection, maintenance and reparation . Thus , the components in elevator shafts need to be accessed . Uncontrolled access to elevator shafts , however, is potentially dangerous and often regulated by the law or other of ficial regulations .

[0005] Elevator shafts often have space below the lowest elevator landing floor . The space can be used, for example , for providing safety buffers . The space i s also often used by maintenance people for elevator maintenance . The empty space below the lowest f loor is called a pit , which may contain in the following disclosure a free space , refuge or other opening beyond the extreme position of the elevator car . Thus , i f the elevator car for some reason would hit the buf fer on the bottom of the elevator shaft , the safety space in the pit would allow the maintenance person to be in safety inside the pit . Because of this reason, some regulators have considered it necessary to have a pit that is large enough to provide safety for the person working in the elevator shaft .

[0006] Deep pits , however, have drawbacks that may need to be addressed . For example , deep pits make building structures more complex due to ground water pressure . Many cities are located on a coastal area or close to big rivers . This often causes problems with ground water . Thus , it is desired to reduce the need for deep pits as it may be technically complex, causes unnecessary expenses and may limit the freedom of designing the surroundings of the elevator pit .

[0007] One known solution is to have an opening in the floor of the elevator car so that when the cover of the opening is removed the elevator car cannot hit the maintenance person in the pit . In some cases , the pit comprising all equipment that needs to be serviced is not deep so that the maintenance person can perform several di f ferent tasks even from the elevator car by reaching serviced obj ects from the elevator car . When these tasks are performed from the elevator car, there is no risk of being accidentally crushed by the elevator car .

[0008] Another known solution is to remove the emergency opening mechanism from the lowest elevator landing floor and possibly also from other floors . This prevents easy opening of the elevator doors so that the maintenance persons cannot misuse the emergency mechanism to open the landing door for accessing the bottom of the elevator shaft or other parts higher in the elevator shaft , when the elevator car is not on that floor . This , however, has a drawback that it does not prevent opening the landing doors or keeping the landing doors open after opening them using force and di f ferent tools . For example , it is possible to put an obstacle to block the landing doors from closing and then try to move the elevator car so that the elevator car does not block the access to the elevator shaft .

[0009] In Elevators , particularly in high rise buildings , it may be tempting for some maintenance persons to access the bottom of the elevator shaft even i f it may not be safe . This may be seen as a pos sibility to perform the necessary maintenance tasks faster so that the elevator can be kept in operation without unnecessarily long breaks which will cause inconvenience to users of these buildings by increasing waiting times and fuller elevator cars with more stops during j ourneys . Thus , there is a need for providing additional safety mechanisms . Furthermore , as the elevators are critical for the users of multi-storey buildings , there is always a need for technological improvement for making the elevator construction and maintenance simpler and more cost ef ficient , while providing ef ficient and safe elevators for both to passengers and maintenance persons .

[0010] SUMMARY

[0011] In the following disclosure an arrangement for preventing access to an elevator shaft and particularly to the pit of the elevator shaft is disclosed . Elevator shafts commonly have a pit in the bottom of the elevator shaft . Access to the elevator shaft and the pit is prevented by using an arrangement that detects that the elevator is on the lowest floor and prevents moving of the elevator car from the lowest floor when the landing door is still open . Similarly, the arrangement can be used to prevent access to the elevator shaft from any other floor, when the elevator car is not appropriately on that floor . The arrangement improves the safety o f the maintenance personnel as they cannot access the pit, wherein they would in at a risk of crushing under the elevator car . Furthermore , as the maintenance staf f cannot access the elevator shaft there the risk of falling to the elevator shaft is reduced .

[0012] In an aspect an elevator is disclosed . The elevator comprises an elevator car in an elevator shaft connected to a hoisting machine conf igured to move the elevator car, a landing door opening zone at a floor configured to enable opening the landing door of the floor when the elevator car is in the landing door opening zone , and a switch configured to prevent moving of the elevator car from the landing door opening zone while the landing door of the floor is at least partially open . It is beneficial to have an arrangement that prevents movement of the elevator car so that the safety of the maintenance staf f is increased .

[0013] In an example implementation the switch i s an electro-mechanical switch configured to disconnect the power of the brakes . It is beneficial to have an electromechanical switch that forces disconnecting the power of the brakes so that the elevator cannot be moved until the power to the brakes is engaged again .

[0014] In an example implementation the electromechanical switch engages when the elevator car arrives at the landing door opening zone . It is beneficial to engage the switch when the elevator is in the door opening zone . When the elevator is in the door opening zone the elevator is located so that the moving in and out of the elevator is safe and convenient . Thus , it is not poss ible to access the pit when the elevator is in the door opening zone .

[0015] In an example implementation the electromechanical switch comprises a delay timer after which the power is disconnected . It is beneficial to have a timer so that the switch can be engaged before the elevator car is stopped . The timer facilitates a smooth stop before the timer expires and prevents moving of the elevator car .

[0016] In an example implementation the switch engages when the landing door is opened . It is beneficial to arrange the switch so that it is engaged when the landing door is opened . This guarantees that the elevator has already been stopped .

[0017] In an example implementation the switch is a magnetic switch configured to disconnect the power of the brakes . It is beneficial to have a switch that is based on the magnetic force . This facilitates using a switch that is less prone to mechanical wearing .

[0018] In an example implementation the switch is configured to actuate a mechanism to disconnect the power of the brakes . It is beneficial to have a separate mechanism that disconnect the power from the brakes . This facilitates positioning the mechanism for disconnecting the power to a location that is optimal for the purpose .

[0019] In an example implementation the switch is configured to receive a signal from one or more safety switches . It is beneficial to connect to other safety switches of the elevator so that all prevailing conditions can be taken into account . Thi s increases the security as any reason that should prevent moving of the elevator car can be taken into account and the elevator car will not move and open the access to the pit .

[0020] In an example implementation the switch is configured to : receive an indication from the lowest landing door that the door is open and the elevator car door is closed; and as a response to the received indication the switch is configured to prevent moving of the elevator car . It is beneficial to include a separate check if both of the doors are closed . I f only passenger safety inside the elevator car is considered it may open a pos sibility for maintenance personnel to access the elevator pit and it may cause dangerous situations .

[0021] In an example implementation the switch is configured to receive the pos ition o f the elevator car from a position sensor ; and wherein, the position sensor indicates that the elevator car is in the lowest landing door opening zone , the switch is further configured to prevent moving of the elevator car from the lowest landing door opening zone when the landing door on the lowest floor is at least partially open . It is benef icial to use a pos ition sensor of the elevator so that it is not necessary to install additional components to the lowest floor .

[0022] In an example implementation the switch is configured to prevent the moving by transmitting instructions to a controller of the hoisting machine . It is beneficial to provide instructions to the controller of the hoisting machine so that the hoisting machine does not move the elevator car before the instructions to prevent moving are li fted . This provides a possibility to prevent moving of the elevator car without additional components that need to be installed to the electrical circuit of the brakes .

[0023] In an example implementation the switch is further configured to prevent moving by transmitting instructions to a brake controller to keep the brakes in a closed position . It is beneficial to send a message to the brake controller to keep brakes engaged until the instructions are li fted . This provides a possibility to prevent moving of the elevator car without additional components that need to be installed to the electrical circuit of the brakes .

[0024] In an example implementation closing the landing door is conf igured to disengage the switch . It is beneficial to couple the switch with the landing door . When the landing door is completely closed, it is safe to move the elevator car again .

[0025] In an aspect a method for preventing access to the elevator shaft pit is disclosed . The method comprises : detecting an elevator car arriving at a landing door opening zone at a floor ; preventing moving of the elevator car from the landing door opening zone when the landing door of the floor is at least partially open .

[0026] In an example implementation of the method the preventing moving of the elevator car further comprises disconnecting the power of the brakes . It is beneficial to disconnect the power of the brakes so that the elevator cannot be moved unti l the power to the brakes is engaged again .

[0027] The aspects and example implementations described in the above provide a possibility to prevent the access to the elevator pit and improve the safety of the maintenance personnel by reducing the risk of being crushed under the elevator car . Furthermore , the above aspects and example implementations may be used in preventing access to the elevator shaft al so higher locating floors . This reduces the risk of falling to the elevator shaft and thus reduces accidents that can cause severe inj uries and be li fe threatening .

[0028] BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings , which are included to provide a further understanding of the arrangement for preventing access to an elevator shaftto an elevator shaft and constitute a part of this speci fication, illustrate embodiments and together with the description help to explain the principles of the arrangement for preventing access to an elevator shaftto an elevator shaft . In the drawings :

[0030] Fig . 1 is a block diagram of an example embodiment of the arrangement for the arrangement for preventing access to an elevator shaftto an elevator shaft ,

[0031] Fig . 2 is a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft ,

[0032] Fig . 3 is a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft ,

[0033] Fig . 4 is a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft , and

[0034] Fig . 5 is a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator .

[0035] DETAILED DESCRIPTION

[0036] Reference will now be made in detail to the embodiments , examples of which are illustrated in the accompanying drawings .

[0037] In figure 1 a block diagram of an example embodiment of the arrangement for preventing access to an elevator shaft is disclosed . In the figure an example of an elevator is shown . This elevator is only an example of an elevator . The present arrangement is suitable for any elevator and particularly for those with a pit extending below the lowest floor . Furthermore , the present arrangement is also suitable for preventing any access to the elevator shaft from any of the floors . Even i f the lowest floor is discussed in more detail , the same arrangements can be constructed in any of the floors .

[0038] In the example of figure 1 only one elevator is shown, however, particularly in high rise buildings there are typically a plurality of elevators in an elevator group and some of the services may be shared with other elevators . Many of the safety related features , however , may need to be independent for each of the elevators in an elevator group so that highest possible level of security can be reached . Many other features may be shared and the information from neighboring elevators may be used . For example , elevator j ourneys may be scheduled using the knowledge on locations of other elevator cars and scheduled calls and j ourneys . Furthermore , the elevator car of the following examples is located on the lowest floor as it is the most common example because of the possibility of using the pit is potentially more often used inappropriately . As mentioned earlier, the similar principles may be used in preventing access to the elevator shaft on any of the floors .

[0039] The elevator of the example comprises an elevator shaft 100 , wherein an elevator car 102 runs up and down . The elevator car 102 is connected to a hoisting arrangement 104 using one or more ropes 106 . The ropes are also connected to a counterweight 108 . The counterweight runs into the opposite direction with the elevator . The ropes are arranged to run through one or more sheaves . The ropes are used only as an example of hoisting means . Instead of ropes it is possible to use , for example , a belt or any other suitable means .

[0040] The hoisting arrangement 104 is illustrated here in the top of the shaft 100 , however, this is only for illustrative reasons . The hoisting machine and other components illustrated in the figure may be located in di f ferent locations , which depending on the component , may be located in the shaft or outside the shaft . In very traditional elevators the hoisting machine and machine room were located on the top of the shaft 100 , however, in some elevators separate machine rooms are not needed . Furthermore , hoisting may be arranged also from the bottom of the shaft by arranging the ropes appropriately so that the possible machine room may be located at any floor considered suitable for the building . In the bottom of the shaft the elevator according to the example of figure 1 comprises a pit area 116 that is below the lowest floor . The dashed line 118 shows the floor level on the lowest floor . The doors of the elevator are opened when the elevator reaches door opening zone 120 . The door opening zone enables opening the doors . This should be understood as an authori zation or activation of a possibility to open the doors . The arrival to the door opening zone does not open the doors as such but there is a separate mechanism that can be used only in the door opening zone . The elevator doors are typically arranged so that the lowest floor does not have a possibility to open the doors from the floor-side , but the doors are opened by the elevator car or other component that cannot be manually operated from the landing side . When the elevator reaches the door opening zone, the locking mechanism of the landing doors is opened and the door mechani sm of the elevator car can open the landing doors . It is possible that other types of door mechanisms are used, however, the basic principle that the doors are opened only when the elevator car is at the door opening zone is followed . The elevators may have di f ferent mechanisms for detecting that the elevator car is in the door opening zone . There may be speci fic sensors or controllers for that or the elevator may know the location of the elevator car otherwise . It is also possible to design opening mechani sms so that when the elevator car doors is opened, it will open only i f it is located in the door opening zone and it will also open the landing doors simultaneously .

[0041] The example of figure 1 further comprises a switch 122 , that is configured to prevent access to the elevator shaft by preventing moving of the elevator car when the lowest landing door is open . The switch may be implemented in various ways as explained in the following .

[0042] The switch may be implemented as a mechanical switch, electro-mechanical switch, software implemented switch or similar or any combination of those . The switch must be implemented in a manner so that it prevents moving of the elevator car when the switch is engaged or activated . The prevention of movement can be implemented, for example , by disconnecting the power from the brakes so that the brakes are engaged until the switch is released and the brakes get power again or simply placing instructions to an elevator controller 110 that controls the elevator movement , or in any other suitable manner that prevents moving of the elevator car while the switch is engaged, activated or in a state configured to prevent moving of the elevator car . The instructions may include , for example , instructions that the brakes cannot be released or that the instructions instructing the hoisting machine to move the elevator are blocked .

[0043] One example of a switch comprises a mechanical part that forces the electric circuit of the brakes open . Thus , when the elevator car arrives at the lowest landing floor, or any other floor with a similar switch, a mechanical actuator part , such as a ramp or s imilar, mechanically pushes or pulls the circuit open . The mechanical part keeps the circuit open until the elevator car is moved out of the door opening zone . The mechanical switch can be arranged so that it is located in any location on the elevator car and has a counterpart in the corresponding location in the elevator shaft side . The location must be arranged so that the switch is activated when the elevator car arrives at the door opening zone and preferably before the doors are opened . In order to prevent a sudden stop that may be inconvenient to the passengers the switch may include an additional timer part , which, for example, keeps the switch disengaged or open until a predetermined time period has passed after which the switch engages and opens the electrical circuit of the brakes . When the doors are closed again, and cannot anymore be opened from the outside , the switch is disengaged . This may be arranged by having a switch that is mechanically connected to the doors or using an electric actuator to release the switch or similar automatically when the doors are closed again . Another example of a switch is a magnetic detector that is activated when the counter parts of the switch meet when the elevator car arrives at the door opening zone . The magnetic detector may activate an electric actuator that opens the circuit similarly as the mechanical actuator part . Instead of a mechanical actuator the electricity can be turned of f by us ing an electrical switch that disconnects the brakes from the power when the elevator car is at the door opening zone . When the electricity is turned of f , the brakes cannot be opened and it is not possible to move the elevator car . Accordingly, the magnetic switch arrangement can comprise a delay timer that turns the electricity of f only after a predetermined period of time so that smooth landing can be guaranteed instead of a fast stop . The magnetic switch, as well as the mechanical switch of the previous example , may be connected to the doors . Thus , in that case the switch engages only when the doors are opened . The engagement may be implemented so that the switch is engaged when doors are still closed but the opening mechanism starts to open the doors . In that case the delay timer is not necessary as the elevator car has already been stopped . The magnetic switch may also be used with a mechanism that uses a computer program to engage the brakes or prevent the moving of the elevator car . The switch sends a signal to the controller of the elevator so that the controller prevents all further moving until the switch is disengaged .

[0044] Instead of a mechanical , electro-mechanical or similar switch on the lowest floor, or any other floor, the switch may also be software implemented switch . The software implemented switch may be , for example , a computer program that i s executed in the control ler of the elevator . The software implemented switch acquires the position of the elevator car from elevator car position sensors or other sensors that are capable of providing exact location of the elevator car . One option is to acquire the information when the elevator car starts opening the doors and as a response will turn the brakes and / or hoisting machine into a mode where moving the elevator car is not possible . Similarly, when the software implemented switch acquires the information that the doors are closed again, the switch disengages and allows moving of the elevator car .

[0045] In figure 2 a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft is disclosed . In the method the elevator is operated in a usual manner and the elevator car is arriving at the lowest f loor . When the elevator car arrives at the lowest floor, the elevator is configured to detect the arrival also for purposes of the preventing pit access , step 200 . Pit acces s may be dangerous as i f there is not enough room below the elevator car there is a ri sk of crushing . In many cases the constructors and owners of the buildings do not want a deep pit below the elevator as it is structurally di f ficult and expensive to have deep pits . It is known that sometimes maintenance persons access the pit even i f that is not allowed . In order to improve the safety of an elevator access to the pit should be prevented in all conditions . This includes particularly us ing force to keep the elevator doors open and moving the elevator away from the lowest floor . Accordingly, the access to the elevator shaft from higher floors is obviously dangerous because of a risk of falling to the elevator shaft .

[0046] The detecting step 200 may be done in several di fferent ways . For example , there may be a switch that is configured to detect when the elevator arrives at the door opening zone . The door opening zone is a zone , wherein the doors of the elevator car can be opened . Typically the elevator car controls also opening the landing door . The door opening zone is determined so that passengers of the elevator car can access the elevator conveniently and safely . The switch may detect the arrival be fore opening the doors or when the doors are actually opened .

[0047] When the elevator detects that the elevator car is in the door opening zone on the lowest floor, the elevator prevents moving of the elevator, step 210 . Moving of the elevator includes here any moving in normal use o f the elevator than the ordinary moving o f the elevator after the doors have been closed and the elevator car starts next j ourney for transporting passengers from the lowest floor or travelling to a floor where passengers are waiting for an elevator . In addition to the moving in the normal use the moving includes any other moving, for example , forcing moving the elevator car in an unauthori zed manner using emergency mechanisms . Thus , the purpose of the method is to prevent moving the elevator when the landing door is open, for example , because of obstacles preventing closing of the door or some other mechanism that prevents closing of the door . When the elevator car cannot be moved while the door is at least partially open . Thus , it is not possible to access the pit . Partially open should be understood here to mean that the door is not completely closed . For example , a maintenance person could place a screwdriver or a flat piece of metal between the door leaves . This might partially close the door so that the screwdriver or other tool can be used to force the door to open again . For thi s reason, the arrangement is configured so that the door is completely closed before the switch is disengaged and allows moving of the elevator car .

[0048] In figure 3 a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft is disclosed . The example of figure 3 is suitable for implementations using an electro-mechanical switch . The method starts by detecting the elevator arriving at the door opening zone , step 300 . In the example of figure 3 the switch is implemented in a manner that it activates when the elevator stops . The switch may be exactly on the location where the stopping o f the elevator i s desired or the switch may be connected to the elevator car doors or landing doors .

[0049] The electro-mechanical switch may be configured so that a mechanical part pushes or pull s a second switch in the electric circuit controlling the electric supply to the brakes off the elevator, step 310 . The brakes are typically configured so that the brakes are kept open using electric power . In case of electricity outage , the brakes will activate , and the elevator will stop . Similarly, when the mechanical switch, such as a ramp, guidance rai l or other mechanism for pushing or pulling the circuit open will disconnect the brakes from the electric power and the elevator car cannot be moved anymore . The mechanical part can directly push or pull the electric circuit controlling the electric supply, or there may be other actuators that are operated, for example , by using an electric motor or other electronic components to disconnect the electric power of the brakes . The switch is typically configured in a manner that the electric power is disconnected by latest when the doors start to open .

[0050] After the stop on the lowest floor the elevator detects that the doors are again closed, step 320 . This may be done using the same switch or using a second separate switch, that detects that the landing door is completely closed and does not allow unauthori zed opening for accessing the pit or other parts of the elevator shaft . When the landing door i s closed again, the power of the brakes is connected, step 330 . Here it should be noted that it does not necessari ly mean that the brakes are immediately released, however, the circuit is again closed so that the brakes can be released when the controller of the elevator instructs to do so . Thus , the controller of the elevator may instruct the hoisting machine to move the elevator car again .

[0051] In figure 4 a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft is disclosed . The example of figure 4 is similar to the example of figure 3 , wherein an electro-mechanical switch detects that the elevator car arrives at the door opening zone on the lowest f loor, step 400 . In the example of figure 4 the switch i s arranged so that the switch engages when the elevator is still moving . The switch may be engaged when the elevator arrives at the door opening zone or even before the arrival . In the example of figure 4 the switch comprises or is connected to a delay timer that is activated, step 410 , when the elevator car is detected to arrive at the door opening zone . The delay timer may be set for any predetermined period so that when the elevator activates the switch, the predetermined time is suf ficient for allowing the elevator to stop smoothly . After expiration of the delay timer, the power of the brakes is disconnected, step 420 . In a further example , the controller is configured so that the elevator car cannot open the doors before the power is disconnected, when the elevator car is on the lowest floor . This is an additional and optional safety measure .

[0052] After the stop, the doors are again closed and the elevator detects completely closed doors , step 430 . After the success ful detection step, the power of the brakes can be connected, step 440 .

[0053] In figure 5 a flow chart of an example of a method of arrangement for preventing access to an elevator shaftto an elevator shaft is disclosed . In the example of figure 5 the elevator detects that the elevator car is arriving at the door opening zone, step 500 . In the previous examples electro-mechanical switches were used . It is pos sible that in the example of figure 5 the elevator car comprises a switch for detecting the location of the elevator car, however, this can be implemented as a software switch . The controller of the elevator may determine that the elevator car is located in the door opening zone on the lowest floor by using di f ferent positioning means that can provide the location of the elevator car to the controller and may be used also for other purposes . The position sensor may be optical or mechanical based on an own or shared rope running in the elevator shaft . The software implemented switch receives the location of the elevator car and sends a message to the elevator controlling part of the software or hardware to prevent all instructions to move the elevator car until the prevention order is li fted, step 510 . The component responsible for moving the elevator, such as the controller of the hoisting arrangement then prevents moving the elevator, step 520 . The component may be a controller sending instructions to the hoisting arrangement or a controller at the hoisting arrangement . Similarly, as with the example of figure 4 , the elevator may be configured so that the controller of the elevator al lows opening the doors on the lowest floor only when the prevention to move the elevator is in force . Thus , the arrangement is implemented as a sequence of actions , wherein the earlier action must be success fully performed before the next action can be taken .

[0054] When the controller receives a signal or message indicating that the doors of the elevator are again closed, step 530 , a second message is sent to the controller, step 540 . The second message instructs that the elevator can be moved again . In the example of figure 5 it is not necessary to disconnect the brakes from the electric power, however, it can be done i f desired, for example , because of local regulations .

[0055] In the examples above several specific ways to implement an arrangement for preventing access to an elevator shaft are disclosed . The examples may include use of additional information, such as receiving and combining information from other safety switches or other safety related devices . The purpose of the arrangement is to prevent moving the elevator car so that it is pos sible to gain the access to the elevator shaft pit . Even i f speci fic implementation details are given, it is possible to supplement this information by receiving any other reasons why the elevator car should not be moved . These features may be integrated to the present arrangement or be provided in an elevator as independent components or subsystems . In such implementation the elevator i s not moved i f any of the subsystems is indicating that the elevator car should not be moved .

[0056] In the above examples o f methods and required arrangements have been discussed . The person skilled in the art understands that these are only examples and is able to implement the arrangement also in various other ways provided that there is a switch or mechanism for detecting that the elevator arrives at the door opening zone on the lowest floor . As a response to the arrival the moving the elevator car is prevented using a mechanism that is appropriate for the particular elevator . Moving of the elevator car is allowed again only after the landing door is closed so that nobody can access the pit of the elevator shaft .

[0057] As stated above , the components of the exemplary implementations can include computer readable medium or memories for holding instructions programmed according to the teachings of the present inventions and for holding data structures , tables , records , and / or other data described herein . Computer readable medium can include any suitable medium that participates in providing instructions to a processor for execution . Common forms of computer-readable media can include , for example , a floppy disk, hard disk, magnetic tape , any other suitable magnetic medium, a CD-ROM, DVD, Blu-ray Disc, any other suitable optical medium, a RAM, a PROM, an EPROM, a FLASH-EPROM, any other suitable memory chip or cartridge , a carrier wave or any other suitable medium from which a computer can read .

[0058] It is obvious to a person skil led in the art that with the advancement of technology, the basic idea of the arrangement for preventing access to an elevator shaft may be implemented in various ways , arrangement for preventing access to an elevator shaftto an elevator shaft and its implementations are thus not limited to the examples described above ; instead they may vary within the scope of the claims .

Claims

CLAIMS1 . An elevator comprising : an elevator car in an elevator shaft connected to a hoisting machine configured to move the elevator car ; a landing door opening zone at a floor configured to enable opening the landing door on the floor when the elevator car is in the landing door opening zone ; and a switch configured to prevent moving of the elevator car from the landing door opening zone while the landing door on the floor is at least partially open .2 . An elevator according to claim 1 , wherein the switch is an electro-mechanical switch configured to disconnect the power of the brakes .3 . An elevator according to claim 2 , wherein the electro-mechanical switch engages when the elevator car arrives at the landing door opening zone .4 . An elevator according to claim 3 , wherein the electro-mechanical switch comprises a delay timer after which the power is disconnected .5 . An elevator according to claim 3 , wherein the switch engages when the landing door is opened .6 . An elevator according to claim 1 , wherein the switch is a magnetic switch configured to disconnect the power of the brakes .7 . An elevator according to claim 6 , wherein the switch is configured to actuate a mechanism to disconnect the power of the brakes .8 . An elevator according to claim 1 , wherein the switch is configured to receive a s ignal from one or more safety switches .9 . The elevator according to claim 8 , wherein the switch is configured to : receive an indication from the lowest landing door that the door is open and the elevator car door is closed; and as a response to the received indication the switch is configured to prevent moving of the elevator car .10 . The elevator according to claim 1 , wherein the switch is configured to receive the position of the elevator car from a position sensor ; and wherein, the position sensor indicates that the elevator car is in the landing door opening zone , the switch is further configured to prevent moving of the elevator car from the lowest landing door opening zone while the landing door on the floor is still open .11 . The elevator according to claim 10 , wherein the switch is configured to prevent moving by transmitting instructions to a controller of the hoisting machine .12 . The elevator according to the claim 10 , wherein the switch is further configured to prevent the moving by transmitting instructions to a brake controller to keep the brakes in a closed position .13 . An elevator according to any of preceding claims , wherein closing the landing door is configured to disengage the switch .14 . A method for preventing access to the elevator shaft pit , the method comprising : detecting an elevator car arriving at a landing door opening zone at a floor ;preventing moving of the elevator car from the landing door opening zone when the landing door on the floor is at least partially open .15 . A method according to claim 14 , wherein the preventing moving of the elevator car further comprises disconnecting the power of the brakes .

Images