Patent Description:
In a no-headroom or low-headroom elevator, the height of the shaft is such that a person or an object on the elevator car roof will be crushed when the elevator car approaches the top landing. For the overall safety of such elevators, it is imperative to monitor that there is no undue presence on the elevator car roof when the elevator is in operation. For such elevators, one way of providing the necessary safety or refuge space for elevator maintenance operations, such as service and inspection for components in an elevator shaft, is to establish it inside the elevator car. The maintenance may be performed, for example, through an opened car ceiling and roof, flooring or walls or through open car doors. In this case, the permanent and natural refuge space is located at least partially inside the elevator car. In the above-mentioned applications, a car inspection drive may be performed from inside the elevator car by using an opened car roof as the service access to the elevator shaft above the car.

<CIT> discloses a solution for an elevator having a low headroom.

<CIT> discloses an elevator car with a working platform.

Example embodiments provide an elevator car roof system for providing a safe and an easy access for elevator maintenance by monitoring an opening state of an elevator car roof. In an example embodiment, the elevator car roof system enables an object detection on top of the elevator car roof to further enhance the safety. These benefits may be achieved by the features of the independent claim <NUM>. Further implementation forms are provided in the dependent claims, the description, and the drawings.

According to an aspect, there is provided an elevator comprising an elevator car roof system. The elevator car roof system comprises a plurality of movable roof panels forming an elevator car roof, at least one sensor configured to indicate positions of the roof panels and to detect an object on at least one roof panel, the positions comprising at least a first state in which the roof is fully closed, a second state in which the roof is fully open and a third state in which the roof is partially open. The elevator further comprises a control system configured to receive at least one signal from the at least one sensor of the elevator car roof system. The control system is configured to enable normal elevator operation based on at least one signal received from the at least one sensor only in the first state when no object is detected on the roof, the control system is configured to, based on at least one signal received from the at least one sensor, disable any elevator operation in the third state or when an object is detected on the roof, and the control system is configured to enable an elevator inspection drive based on at least one signal received from the at least one sensor only in the second state.

In an example embodiment, the roof is partially open when at least one roof panel has turned away from a plane of an elevator car roof relative to a longitudinal axis of the roof panel.

In an example embodiment, the roof is fully open when all roof panels have turned away from the plane of the elevator car roof relative to the longitudinal axis of the roof panels and moved to one side of the elevator car roof opening.

In an example embodiment, wherein the roof is fully closed when the roof panels are positioned side by side in the same plane, covering the whole area of the elevator car roof opening.

In an example embodiment, the at least one sensor comprises a first sensor, a second sensor and a third sensor, and wherein the system further comprises a frame of the elevator car roof; a first folding lever movably coupled to one side of the frame, and a second folding lever movably coupled on the opposite side of the frame than the first folding lever. The first folding lever is configured to enable triggering of at least one of the first sensor and the second sensor, and the second folding lever is configured to enable triggering of the third sensor.

In an example embodiment, in the first state and when weight is applied on any of the roof panels, the first folding lever is configured to trigger the first sensor.

In an example embodiment, in the third state, the first folding lever is configured to trigger the first sensor and the second sensor.

In an example embodiment, in the second state, the second folding lever is configured to trigger the third sensor to override the first sensor and the second sensor, to enable an inspection drive.

In an example embodiment, the system further comprises at least one pushing member associated with each roof panel arranged to face the first folding lever, and wherein when weight is applied if the first state, the at least one pushing member is configured to move the first folding lever and in response to the movement, the first folding lever is configured to trigger the first sensor.

In an example embodiment, the first folding lever extends along the whole side of the frame.

In an example embodiment, the second folding lever extends only partially along the side of the frame.

Many of the attendant features will be more readily appreciated as they become better understood by reference to the following detailed description considered in connection with the accompanying drawings.

The accompanying drawings, which are included to provide a further understanding of the example embodiments and constitute a part of this specification, illustrate example embodiments and together with the description help to understand the example embodiments. In the drawings:.

Reference will now be made in detail to example embodiments, examples of which are illustrated in the accompanying drawings. The detailed description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present example may be constructed or utilized. The description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be accomplished by different examples.

According to an example embodiment, an elevator car roof system is provided for monitoring safety of a service access located on an elevator car roof. The elevator car roof system may monitor a change in an opening state of the elevator car roof. Positions of a plurality of roof panels may indicate when the elevator car roof is partially open, fully open or fully closed. The positions of the roof panels may cause at least one sensor of the elevator car roof system to provide a signal to a control system of the elevator. Further, the elevator car roof system may detect if there is an object on the roof. Based on the detected object on the roof, the elevator car roof system may provide at least one signal to enable controlling operation of the elevator. The elevator car roof system may, for example, enable or disable normal operation of the elevator, or enable or disable performing an inspection drive on the elevator.

The monitoring mechanism may comprise a plurality of roof panels within a frame of the car roof. The roof panels may form a platform on the car roof when they are closed, i.e. the elevator car roof top. The roof panels may be separate or connected, and they may be moved such that they are stowable or foldable on one end or side of the frame of the elevator car roof. Hence, the elevator car roof may be fully opened to provide a service access from inside the elevator car. Further, the stowing or folding of the panels on one side may enable that visibility to the elevator shaft is not blocked by the roof when the roof is opened. A normal operation of the elevator may be enabled only when the elevator car roof is fully closed and there is no object on the elevator car roof. An inspection drive may only be enabled when the elevator car roof is fully opened. This is enabled by monitoring the opening state of the roof panels and, respectively, the opening state of the elevator car roof. For enhanced safety, the elevator car roof system may further detect objects on the roof panels and restrain operation of the elevator in response to detecting an object on at least one panel. The solution may provide a safe and a practical service access from the elevator car to the shaft.

<FIG> illustrates a schematic representation of a control system <NUM> of an elevator system comprising an elevator car roof system <NUM> according to an embodiment. Although the control system <NUM> is illustrated as a single device, it is appreciated that, wherever applicable, functions of the control system <NUM> may be distributed to a plurality of devices.

The control system <NUM> may comprise a control unit <NUM>, such as an elevator controller. The control unit <NUM> may comprise at least one processor, for example, one or more of various processing devices, such as for example a co-processor, a microprocessor, a controller, a programmable logic controller (PLC), a digital signal processor (DSP), a processing circuitry with or without an accompanying DSP, or various other processing devices including integrated circuits such as, for example, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a microcontroller unit (MCU), a hardware accelerator, a special-purpose computer chip, or the like.

The control unit <NUM> may further comprise at least one memory. The memory may be configured to store, for example, computer program code or the like, for example operating system software and application software. The memory may comprise one or more volatile memory devices, one or more non-volatile memory devices, and/or a combination thereof. For example, the memory may be embodied as magnetic storage devices (such as hard disk drives, magnetic tapes, etc.), optical magnetic storage devices, or semiconductor memories (such as mask ROM, PROM (programmable ROM), EPROM (erasable PROM), flash ROM, RAM (random access memory), etc.).

The control system <NUM> may comprise the elevator car roof system <NUM>. The elevator car roof system <NUM> may comprise an electrical safety control interface <NUM> configured to provide signals for the control unit <NUM>. The electrical safety control interface <NUM> may comprise, for example, one or more sensors or switches connected to the control unit <NUM>. The electrical safety control interface <NUM> may further comprise one or more safety input modules configured to detect safety-related switching states of the sensors such as position switches, safety contacts, magnetic switches, roll safety switches, or the like. In an example embodiment, the safety input modules may comprise instructions to turn on and off outputs based on input conditions and an internal program. The instruction may be stored, for example, on a PLC configured in the safety input module. Alternatively, the safety input modules may provide output signals based on the input conditions for a separate controller, such as the control unit <NUM>. In an embodiment, the control unit <NUM> may be integrated on the one or more safety input modules. The electrical safety control interface <NUM> may further comprise a communication interface configured to enable the elevator car roof system <NUM> to transmit and/or receive information, to/from other devices, such as service or maintenance devices, or the like.

The elevator car roof system <NUM> may further comprise control mechanics <NUM> configured to trigger the input signals by the electrical safety control interface <NUM> to the control unit <NUM>. The control mechanics <NUM> may comprise, for example, one or more levers configured to trigger one or more sensors. For example, the levers may be configured to change a state of at least one switch in response to a changed position of the one or more levers. The control mechanics <NUM> may further comprise a plurality of panels, such as folding panels, hinged swing plates and/or floating plates. In an example embodiment, the roof panels are movably coupled within a frame of an elevator car roof as separate panels. In another example embodiment, the roof panels may be interconnected. The roof panels may be associated with the at least one sensor such that changed positions of the roof panels cause changes in states of the sensors. Each roof panel may be configured to be movable horizontally and vertically or to be pivotable. In an example embodiment, the one or more levers may be provided operatively coupled to the roof panels. Changes in positions of the roof panels may move the one or more levers. The elevator car roof system <NUM> may further comprise one or more springs coupled with the one or more levers and/or plates for keeping and/or returning the one or more levers and/or plates in a default position.

The functionality described herein may be performed, at least in part, by one or more computer program product components such as software components. According to an embodiment, the elevator car roof system comprises a processor or processor circuitry, such as for example a microcontroller, configured by the program code when executed to execute the embodiments of the operations and functionality described. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs), application-specific Integrated Circuits (ASICs), application-specific Standard Products (ASSPs), System-on-a-chip systems (SOCs), Complex Programmable Logic Devices (CPLDs), Graphics Processing Units (GPUs).

<FIG> illustrates a schematic representation of an elevator service access when an elevator car roof is fully closed according to an example embodiment.

An elevator car <NUM> may comprise a car ceiling panel <NUM>, which is opened inside the elevator car <NUM>. The elevator car roof may comprise a plurality of separately movable roof panels <NUM> within a frame of an elevator car top. In another example embodiment, the roof panels may be interconnected. The plurality of roof panels <NUM> may fill the frame so that they form a uniform surface within the frame. The plurality of roof panels <NUM> may form an outer surface of the elevator car roof, which may be used for service access. A working platform <NUM> for service and inspection purposes may be stored inside the elevator car roof, between the car ceiling panel <NUM> and the plurality of roof panels <NUM>. When the service access located on the roof is closed, the maintenance person <NUM> may, for example, work on landing door components <NUM> through an opened car door. The elevator car <NUM> may further comprise a car connection board <NUM>. The car connection board <NUM> may provide an interface for internal and external inputs/outputs. For example, the car connection board <NUM> may connect input signals from sensors coupled with the elevator car roof elements <NUM>, <NUM> and a control unit of the elevator. An inspection drive unit <NUM> may be coupled to the car connection board <NUM> by the maintenance person <NUM> to receive information about a state of the elevator and to switch on an inspection mode of the elevator. While the elevator car roof service access is fully closed, a normal operation of the elevator may be allowed.

<FIG> illustrates a schematic representation of the elevator service access of <FIG> when the elevator car roof is fully open according to an example embodiment. The plurality of roof panels <NUM> may be moved separately or in connection with each other and stowed or folded on one side of the elevator car roof opening to open the elevator car roof by a maintenance person <NUM> to form an open service access to the shaft. A roof panel may be in the opened position, when the panel is turned away from the plane of the frame, being preferably orthogonal to the plane of the frame. In the orthogonal position, the roof panels may be stowed in a smaller space next to each other to the one end of the frame. The working platform <NUM> may be folded downwards from the elevator car roof to provide a standing platform for the maintenance person <NUM>. The elevator car roof service access may enable service work on shaft components <NUM> located above the elevator car <NUM>. The shaft components <NUM> may comprise, for example, a motor and a counterweight of the elevator.

Stacking the roof panels <NUM> on the one end of the elevator car top frame may enable providing a refuge space inside the elevator car <NUM> to the maintenance person <NUM>. Further, the arrangement of stowing aside the roof panels <NUM> may enable providing a wider service access, for example, compared to having a roof which rises upwards outside the elevator car <NUM>. The stowing aside of the roof panels <NUM> may further overcome safety risks because visibility to the shaft is not blocked by the roof component rising outside the elevator car <NUM>. Good visibility to the elevator shaft is important during driving in inspection drive mode in the up direction. Further, maintenance and inspection operations may be a performed more easily compared to a rising elevator car roof solution. For example, by sliding and stowing the elevator car roof to one side, the maintenance person is able to replace ropes and a machine located on top of the car with less effort than in case of the rising elevator car roof. The changing operations would be time-consuming with the rising roof because the roof would need to be removed completely before the replacements can be done. Furthermore, maintenance of the landing door components <NUM> may be performed via the roof service access instead of the opened elevator door.

When the inner ceiling <NUM> and the outer elevator car roof are fully open by stowing aside the roof panels <NUM>, normal operation of the elevator may be disabled. The maintenance person <NUM> may switch an inspection mode from the engaged inspection drive unit <NUM>, and the inspection drive may be allowed by the control unit via the car connector board <NUM> after detecting that the elevator car roof is fully open.

<FIG> illustrate the elevator <NUM> of <FIG>, when the elevator car roof is partially open.

In <FIG> the maintenance person <NUM> is standing on the partially closed elevator car roof on top of roof panels 200A which are in a closed position in a plane of the frame of the car top. One or more of the roof panels 200B are in the opened position stowed aside on one end of the frame. If the elevator <NUM> moves while there is a person on the roof, there is a risk of crushing due to insufficient free space above the elevator car. To ensure safety, the panels 200A, 200B may comprise elements that enable detecting an object on the roof panels. The elements may be configured to trigger a signal to the car connection board <NUM> informing about a detected object.

The control unit may further ensure that an inspection or a service drive is allowed only when there is a sufficient refuge space for the maintenance person. Therefore, a control signal allowing the inspection drive may be triggered only when all the panels 200A, 200B are in the opened position and stowed aside at the same end of the frame. In <FIG>, the maintenance person <NUM> is working from a narrow opening because the elevator car roof is not fully open. The refuge space may not be readily available due to the inconvenient working space and thus the inspection drive is disabled for safety.

<FIG> illustrates a schematic representation of an elevator service access when the elevator car roof is fully open depicted from an oblique point of view according to an example embodiment. The elevator service access may comprise a plurality of roof panels <NUM> within an elevator car top frame <NUM>. Dimensions of the roof panels <NUM> may correspond to the width of the frame <NUM> and to the length of the frame <NUM> divided by the number of the panels <NUM>. Sliding rails <NUM> may be coupled on both sides of the frame <NUM>. The sliding rails <NUM> may be configured on any opposite sides of the frame <NUM>.

The roof panels <NUM> may be movable along the sliding rails <NUM>. The roof panels <NUM> may be further movable in relation to their longitudinal axis. Each of the roof panels <NUM> may be separately turned orthogonally in relation to the plane of the frame and slid to one end of the frame. When the plurality of roof panels <NUM> are stowed aside on the one end of the frame <NUM>, the elevator service access may be provided for a maintenance person <NUM>. The maintenance person <NUM> may easily perform maintenance operations via the fully open panel roof, for example, by standing on a working platform <NUM>.

<FIG> illustrates a schematic representation of a monitoring mechanism of an elevator car roof system <NUM> according to an example embodiment. The elevator car roof system <NUM> may provide an integrated and combined system for both roof opening monitoring and person on car top detection. The elevator car roof system <NUM> may be used, for example, for an NHR (No Headroom) elevator application. Object detection and monitoring an opening state of the elevator car roof may be combined into the same mechanism as described.

The elevator car roof system <NUM> may comprise a frame <NUM>. The elevator car roof system <NUM> may further comprise a plurality of movable roof panels <NUM>, <NUM>, <NUM> within the frame <NUM>. In another example embodiment, the roof panels may be interconnected. The roof panels <NUM>, <NUM>, <NUM> may be supported by sliding rails on opposite sides of the frame <NUM>. The elevator car roof is fully closed when all roof panels <NUM>, <NUM>, <NUM> are positioned side by side in the plane of the elevator car top frame <NUM>. When the elevator car roof is fully closed, the plurality of roof panels <NUM>, <NUM>, <NUM> completely fills the frame <NUM>. The elevator car roof may be opened by sliding the roof panels <NUM>, <NUM>, <NUM> to one side of the frame <NUM> and stowing the roof panels to the same side. The roof panels <NUM>, <NUM>, <NUM> may pivotable around their longitudinal axis such that they may be stowed in a relatively small space in relation to the space available in their sliding direction.

The roof panels <NUM>, <NUM>, <NUM> may have a rectangular shape having relatively thin side surfaces and wider top and bottom surfaces. A roof panel may be in a closed position, when the top or bottom surface of the roof panel is in the plane of the frame of the elevator car roof. A roof panel may be in an opened position when the top and bottom surfaces of the roof panel are turned away from the plane of the frame <NUM> around a longitudinal axis of the roof panel within the frame.

The elevator car roof system <NUM> may comprise a first folding lever <NUM> configured under the roof panels <NUM>, <NUM>, <NUM>. The first folding lever <NUM> may be, for example, a longitudinal folding lever plate. The first folding lever <NUM> may be coupled on one side of the frame <NUM>. The roof panels <NUM>, <NUM>, <NUM> may be coupled from their one end to the same side of the frame <NUM> as the first folding lever <NUM>. The length of the first folding lever <NUM> may correspond to the length of the side of the frame <NUM> to which it is coupled to. Hence, the length of the first folding lever <NUM> may be sufficient to trigger at least one sensor <NUM>, <NUM> in response to at least one of the roof panels <NUM>, <NUM>, <NUM> being tilted or a plurality of them being folded. The at least one roof panel tilted or folded away from the plane of the frame <NUM> may simultaneously push the first folding lever <NUM> downwards. The roof panel may push the first folding lever <NUM> from a first position to a second position which may cause the opening state sensor <NUM> to trigger. In response to the triggering of the opening state sensor <NUM>, operation of the elevator may be disabled.

In an example embodiment, each of the roof panels <NUM>, <NUM>, <NUM> may comprise an element or elements enabling object detection on a roof panel or panels.

In <FIG> an exemplary roof panel <NUM> of the elevator car roof system <NUM> is depicted from a side view. The side-view illustrates a short end of the roof panel <NUM> coupled to the same side of the frame <NUM> as the first folding lever <NUM>. Each roof panel <NUM> of the elevator car roof system <NUM> may comprise a swing plate <NUM> coupled to a hinge <NUM>. The swing plate <NUM> may comprise at least one pushing member or a pushing pin <NUM> located above the first folding lever <NUM> when the roof panel <NUM> is in the closed position. In an example embodiment, the swing plate <NUM> may comprise two pushing members or pins <NUM> on both sides of the short end of the roof panel <NUM>. For example, when a person steps on the swing plate <NUM>, one of the pushing pins <NUM> pushes the first folding lever <NUM> so that the first folding lever <NUM> moves or turns and triggers the sensor <NUM>. The length of the one or more pushing pins <NUM> may be selected such that when they are pushed down, the first folding lever <NUM> may reach its intermediate position. When the first folding lever <NUM> is in the intermediate position, only the sensor <NUM> may trigger while the sensor <NUM> remains untriggered. Alternatively, a floating plate may be used instead of the hinged swing plate. Further, a spring or springs may be used to return the plates to their initial position when the object is removed. The spring may be coupled to the first folding lever <NUM>.

The elevator car roof system <NUM> may further comprise a second folding lever <NUM>. The second folding lever <NUM> may be, for example, a longitudinal folding lever plate. The second folding lever <NUM> may be positioned on the opposite side of the frame than the first folding lever <NUM>. The length of the second folding lever <NUM> may be shorter than the length of the first folding lever <NUM>. The second folding lever <NUM> may be partially extending along the length of the side of the frame <NUM> such that the stacking end of the roof panels <NUM> is not covered by the second folding lever <NUM>. For example, the second folding lever <NUM> may begin from the opposite end than where the roof panels <NUM> are stowed and it may extend towards the stacking end such that when all the roof panels <NUM>, <NUM>, <NUM> are in the stowed position in the end, none of the roof panels <NUM>, <NUM>, <NUM> is in connection with the second folding lever <NUM>.

The second folding lever <NUM> may be used to enable an indication when the elevator car roof is fully open. When all the roof panels <NUM>, <NUM>, <NUM> are slid and folded on the one end of the frame <NUM>, the second folding lever <NUM> may turn upwards and trigger the fully open sensor <NUM>. The second folding lever <NUM> may be spring-loaded. At least one roof panel <NUM>, <NUM>, <NUM> being at least partially aligned in with the second folding lever <NUM> in a vertical direction may keep the second folding lever <NUM> in a first position. When the second folding lever <NUM> is in the first position, the fully open sensor <NUM> may be kept untriggered by the second folding lever <NUM>. In response to the last roof panel disconnected from the second folding lever <NUM>, the spring may release the second folding lever <NUM> to a second position and trigger the sensor <NUM>.

Compared to continuously operating object detection means on the elevator car roof, for example, a sensor on the roof frame, unnecessary stops for an elevator car may be avoided while still ensuring safety. For example, a continuously operating sensor on the roof frame may disrupt an inspection drive if a sleeve of a maintenance person blocks the sensor while working. The unnecessary disruptions may be avoided because, once it is detected that the roof is fully open, the fully open sensor <NUM> will override the load on roof sensor <NUM> and enable an inspection drive. In addition, because the object detection is implemented with the same electromechanical mechanism as the opening state monitoring by sensor <NUM>, no additional costs are required by the implementation.

In <FIG> the roof panels <NUM>, <NUM>, <NUM> may be configured to turn in a downwards direction, but in another example embodiment the described operations may be also implemented in the opposite way such that the folding levers may trigger the sensors in response to the roof panels opening in an upwards direction.

<FIG> illustrates a schematic representation of a cross-section of an elevator car roof system when the elevator car roof is fully closed according to an embodiment.

The elevator car roof system comprises a plurality of roof panels <NUM> which may form a surface of the elevator car roof enclosed by the frame <NUM> of the elevator car top. Each of the roof panels <NUM> may have an identical width and the total width of the roof panels <NUM> may correspond to the inner length of the frame <NUM>. When the elevator car roof is fully closed, each roof panel <NUM> may be in the plane of the frame <NUM>.

<FIG> illustrates the elevator car roof service access depicted from above when the elevator roof is fully closed according to an embodiment. Each roof panel <NUM> may be longer in one dimension than in the other, and the length and width of the panels may depend on the dimensions of the frame <NUM>. The length of the roof panels <NUM> may correspond to the inner width of the frame <NUM>. When the elevator car roof is fully closed, the roof panels may form a substantially flat surface.

<FIG> illustrates a schematic representation of a cross-section of an elevator car roof system when the elevator car roof is fully open according to an example embodiment. <FIG> illustrates the elevator car roof system depicted from above. When the elevator car roof is fully open, all roof panels <NUM> are stowed aside on one end of the frame <NUM>, each tilted to an upright position. When the roof panels <NUM> are stowed, they may be in a substantially perpendicular position in relation to the frame <NUM>. Hence, a sufficient space for service access may be provided as the elevator car roof may be folded to side without blocking a view to an elevator shaft.

The elevator car roof system may comprise the first folding lever <NUM> for monitoring a partially open state of the car roof. The first folding lever <NUM> may extend through the whole length of the side of the frame <NUM>. The first folding lever <NUM> may fold downwards in response to at least one of the roof panels <NUM> being tilted to the upright position. In response, the first folding lever <NUM> may trigger the sensor <NUM> configured to disable any movement of the elevator car. The elevator car roof system may further comprise the second folding lever <NUM> for monitoring a fully open state of the car roof. The second folding lever <NUM> may be coupled on opposite side of the frame <NUM> than the first folding lever <NUM>. The length of the second folding lever <NUM> may be shorter than the length of the side of the frame <NUM>. The second folding lever <NUM> may fold upwards in response to all the roof panels <NUM> being stowed aside on the one end of the frame <NUM>. The second folding lever <NUM> may not extend to the stacking end of the roof panels <NUM>. The second folding lever <NUM> may trigger the sensor <NUM> (i.e. the fully open sensor) configured to override sensors <NUM> and <NUM>, thus enabling an inspection drive of the elevator. A roof panel positioned at least partially on top of the second folding lever <NUM> may obstruct the upward movement of the second folding lever <NUM>. Hence, when all roof panels are not stowed aside, the second <NUM> may not be triggered.

<FIG> illustrate a schematic representation of sequences for detecting an object and monitoring an opening state of an elevator car roof in an elevator car roof system according to an example embodiment.

The elevator car roof system may comprise a plurality of jointly or separately movable roof panels <NUM> configured within a frame <NUM> of an elevator car top. The elevator car roof system may further comprise the monitoring mechanism for monitoring opening state of the elevator car roof and a configuration for object detection as described earlier.

In <FIG>, the elevator car roof is fully closed. Each of the roof panels <NUM> is in a closed position in a plane of the frame <NUM> and positioned side by side in the frame <NUM>. The first folding lever <NUM> is in an upward first position and the sensors, such as the switches <NUM>, <NUM> coupled with the first folding lever <NUM>, are closed. On the opposite side of the first folding lever <NUM>, the second folding lever <NUM> is in a downward first position and the switch <NUM> coupled with the second folding lever <NUM> is open.

In <FIG>, the elevator car roof is still fully closed, but a person may be standing on the roof panel <NUM>. The roof panel <NUM> may comprise a floating plate <NUM> comprising at least one pushing member or pin <NUM>. The weight on the roof panel <NUM> may cause the at least one pushing pin <NUM> to push the first folding lever <NUM> downwards to an intermediate position which causes the switch <NUM> to open. Hence, the elevator car roof system may detect an object on the car roof in response to the changed state of the switch <NUM>. In response to the opened switch <NUM>, the operation of the elevator may be disabled. Switches <NUM> and <NUM> remain in their initial state and therefore an inspection drive may not be allowed.

In <FIG>, at least one roof panel <NUM> is in an opened position where the at least one roof panel <NUM> has turned such that a top surface of the panel is no longer in the plane of the frame <NUM>. The turned roof panel or panels <NUM> may push the first folding lever <NUM> downwards to a second position past the intermediate position such that the first folding lever <NUM> causes both the switch <NUM> and the switch <NUM> to open. In response to the changed states of the switches <NUM>, <NUM>, normal operation of the elevator may be disabled by the elevator car roof system. However, when at least one roof panel <NUM> remains in the closed position, the switch <NUM> may remain open and inspection drive is not allowed. The person on top of the roof panel <NUM> may have left, and therefore the floating plate <NUM> may have returned to its initial position.

The open and closed states of the switches <NUM>, <NUM> and <NUM> refer to their connective states as parts of the elevator safety circuit, the switch <NUM> in closed, connective state overriding the switches <NUM> and <NUM> for enabling inspection drive.

In <FIG>, all the roof panels <NUM>, <NUM> within the frame <NUM> have been turned and stowed aside on one end of the frame <NUM>. In response to the last roof panel sliding away from the top of the second folding lever <NUM>, the second folding lever <NUM> may lift up and cause the switch <NUM> to close. When the switch <NUM> is closed, an inspection drive may be allowed by the elevator car roof system, while the normal movement of the elevator may be disabled.

<FIG> illustrates a schematic representation of the first folding lever <NUM> in a first position when an elevator car roof is fully closed according to an example embodiment. The first folding lever <NUM> may remain in the first position while each roof panel <NUM> and the respective swing plate <NUM> is in a horizontal position in a plane A of the roof panel <NUM>. The first switch <NUM> may be kept in a closed state when the first folding lever <NUM> is in the first position.

<FIG> illustrates a schematic representation of the first folding lever <NUM> in an intermediate position when there is an object on the elevator car roof according to an example embodiment. The weight of the object may cause the swing plate <NUM> to move from the plane A of the roof panel <NUM>. For example, one side of the swing plate <NUM> may lift and the other side to drop. The changed position of the swing plate <NUM> may cause the first folding lever <NUM> to move such that switch <NUM> opens but the switch <NUM> is still closed.

8C illustrates a schematic representation of the first folding lever <NUM> in a second position when the elevator car roof is at least partially open according to an embodiment. The roof panel <NUM> may have opened by turning to an upright position. Simultaneously, the first folding lever <NUM> may be pushed by the roof panel <NUM> to a second position. The changed position of the first folding lever <NUM> may cause the switch <NUM> (not shown in figure) to open while switch <NUM> remains open, as illustrated in <FIG>.

<FIG> illustrates a schematic representation of the second folding lever <NUM> in a first position when an elevator car roof is not completely open according to an example embodiment. At least one roof panel <NUM> in a closed position on the plane of the frame <NUM> retains the second folding lever <NUM> in a downwards position. The downwards position of the second folding lever <NUM> may keep the switch <NUM>, coupled with the second folding lever <NUM>, in an open position. Hence, the second folding lever <NUM> and the coupled switch <NUM> indicate the positions of the roof plates and that the elevator car roof is not fully open.

<FIG> illustrates <NUM> schematic representation of the second folding lever <NUM> in a second position when the elevator car roof is fully open according to an example embodiment. When each roof plate <NUM> is turned to an upright position and away from the position of the second folding lever <NUM>, none of the roof panels <NUM> may keep the second folding lever <NUM> in the downward position. Therefore, the second folding lever <NUM> may rise to an upright position. In the upright position, the second folding lever <NUM> may allow the switch <NUM> to close. In response to the closed switch <NUM>, an inspection drive of the elevator may be allowed.

<FIG> illustrates a schematic representation of a monitoring mechanism of an elevator car roof system <NUM> according to another example embodiment.

The elevator car roof system <NUM> may comprise a plurality of separately movable roof panels <NUM>, <NUM> configured within a frame <NUM> of an elevator car top. The roof panels <NUM>, <NUM> may be coupled to sliding rails configured on opposite sides of the frame <NUM>. Each of the roof panels may have a relatively thin rectangular shape having side surfaces and top and bottom surfaces. Each of the roof panels <NUM>, <NUM> may turn around their longitudinal axis such that the roof panel is in a closed position when the top surface of the panel is in a plane of the frame <NUM> and in an opened position when the top surface of the panel is not in the plane of the frame <NUM>. The roof panels <NUM>, <NUM> may turn, for example, <NUM> degrees, <NUM> degrees, or preferably at least <NUM> degrees.

The elevator car roof system <NUM> may comprise at least two sensors <NUM>, <NUM> for roof opening monitoring. In an example embodiment, at least one of the sensors <NUM>, <NUM> may be a safety contact. In an embodiment, at least one of the sensors <NUM>, <NUM> may be a magnetic switch. In an embodiment, at least one of the sensors <NUM>, <NUM> may be a roll safety switch.

In an example embodiment, the elevator car roof system <NUM> may detect that the elevator car roof is fully open when all the roof panels <NUM>, <NUM> are stowed aside on one end of the frame <NUM>. When all the panels <NUM>, <NUM> are stowed aside on the one end, a safety circuit <NUM> on top or below the panel stack is closed. The circuit <NUM> may be coupled to a first sensor <NUM>. When the roof is at least partially closed, at least one roof panel <NUM> is in a closed position. The at least one roof panel <NUM> may close a second safety circuit <NUM> located on the opposite end of the frame <NUM> than the first safety circuit <NUM>. Closing the second safety circuit <NUM> may cause the second sensor <NUM> to trigger. Alternatively, each roof panel <NUM>, <NUM> may be coupled to a separate switch for indicating if the panel is closed. The sensors <NUM>, <NUM> and the respective safety circuits <NUM>, <NUM> may be coupled to a car connection board <NUM> on the frame <NUM>. Input from the sensors <NUM>, <NUM> may be provided via the connection board <NUM>, for example, to a control system of the elevator to at least one of enable only normal elevator operation, enable only inspection drive of the elevator, or disable normal elevator operation.

Rather, the specific features and acts described above are disclosed as examples of implementing the claims.

The operations described herein may be carried out in any suitable order, or simultaneously where appropriate. Aspects of any of the embodiments described above may be combined with aspects of any of the other embodiments described to form further embodiments without losing the effect sought.

The term 'comprising' is used herein to mean including the method, blocks, or elements identified, but that such blocks or elements do not comprise an exclusive list and a method or elevator car roof system may contain additional blocks or elements.

Although subjects may be referred to as 'first' or 'second' subjects, this does not necessarily indicate any order or importance of the subjects. Instead, such attributes may be used solely for the purpose of making a difference between subjects.

Claim 1:
An elevator comprising:
an elevator car roof system (<NUM>) comprising:
a plurality of movable roof panels (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) forming an elevator car roof;
at least one sensor (<NUM>, <NUM>, <NUM>) configured to indicate positions of the roof panels (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and to detect an object on any roof panel,
characterized in that
the positions comprise at least a first state in which the roof is fully closed, a second state in which the roof is fully open and a third state in which the roof is partially open; wherein
the elevator further comprises:
a control system (<NUM>) configured to receive at least one signal from the at least one sensor (<NUM>, <NUM>, <NUM>) of the elevator car roof system (<NUM>);
wherein the control system (<NUM>) is configured to enable normal elevator operation based on at least one signal received from the at least one sensor (<NUM>, <NUM>, <NUM>) only in the first state when no object is detected on the roof;
wherein the control system (<NUM>) is configured to, based on at least one signal received from the at least one sensor (<NUM>, <NUM>, <NUM>), disable any elevator operation in the third state or when an object is detected on the roof; and
wherein the control system (<NUM>) is configured to enable an elevator inspection drive based on at least one signal received from the at least one sensor (<NUM>, <NUM>, <NUM>) only in the second state.