Patent Description:
Elevator systems may be configured with an electronic safety actuator as an alternative to the typical, centrifugal governor. In such electronic safety actuators, a bi-stable magnetic actuator is used to engage the safeties, and thus enable stopping of an elevator car. The safety actuators include magnet assemblies that are configured to provide a friction interface to generate a braking force when activated and engaged with a guide rail of an elevator system. It may be advantageous to provide improved magnet assemblies that may have increased life, lower costs, and/or high braking force.

<CIT> discloses a brake member actuation mechanism for a safety brake member of a hoisted structure includes a brake actuator formed of a ferro-magnetic material configured to be electronically actuated to magnetically engage a guide rail upon detection of the hoisted structure exhibiting a predetermined condition, wherein the magnetic engagement of the brake actuator and the guide rail actuates movement of the safety brake member into a braking position.

<CIT> discloses an elevator system including at least one guide rail. Safety features include safeties to respectively selectively impede or permit movement of an elevator car along a corresponding guide rail, and first and second electronic safety actuators (ESAs) respectively coupled to a corresponding safety. The first ESA includes a first braking surface located a first distance from the corresponding guide rail, the second ESA includes a second braking surface located a second distance from the corresponding guide rail and the first and second braking surfaces are deployable across the first and second distances, respectively, to contact the corresponding guide rails. The elevator system further includes a sensing system to determine the first and second distances and a control system to deploy the first and second braking surfaces toward the corresponding guide rails in response to an overspeed or an over-acceleration condition with synchronization based on the first and second distances.

In accordance with some embodiments, magnet assemblies of electromechanical assemblies for elevator systems are provided in accordance with claim <NUM>.

Some embodiments of the magnet assemblies may include that the material of the encapsulating body is plastic.

Some embodiments of the magnet assemblies may include that the at least one rail engagement block is two rail engagement blocks arranged on opposite sides of the magnet.

Some embodiments of the magnet assemblies may include that the at least one rail engagement block comprises a plurality of teeth.

Some embodiments of the magnet assemblies may include a magnet assembly extension configured to operably connect to a connecting rod of an electromechanical actuator.

Some embodiments of the magnet assemblies may include at least one fastener configured to attach the magnet assembly extension to the at least one rail engagement block.

Some embodiments of the magnet assemblies may include that the target extension is configured to position the proximity switch target at least <NUM> from the magnet.

Some embodiments of the magnet assemblies may include that the proximity switch target is formed from steel.

Some embodiments of the magnet assemblies may include a connector pin configured to engage with a connecting rod to enable actuation of a safety brake.

Some embodiments of the magnet assemblies may include that the connector pin is housed within the encapsulating body.

According to some embodiments, electromechanical actuators of elevator systems are provided in accordance with claim <NUM>.

Some embodiments of the electromechanical actuators may include that the material of the encapsulating body is plastic.

Some embodiments of the electromechanical actuators may include that the at least one rail engagement block is two rail engagement blocks arranged on opposite sides of the magnet.

Some embodiments of the electromechanical actuators may include that the at least one rail engagement block comprises a plurality of teeth.

Some embodiments of the electromechanical actuators may include a magnet assembly extension configured to operably connect to a connecting rod of an electromechanical actuator.

Some embodiments of the electromechanical actuators may include at least one fastener configured to attach the magnet assembly extension to the at least one rail engagement block.

Some embodiments of the electromechanical actuators may include a connecting rod attached to the magnet assembly extension at a first end and a safety brake at a second end.

Some embodiments of the electromechanical actuators may include at least one guide, wherein the electromagnet assembly is moveably mounted on the at least one guide.

Some embodiments of the electromechanical actuators may include a proximity switch, wherein the proximity switch is mounted on an end of the at least one guide and wherein the proximity switch is configured to detect the presence of the proximity switch target.

Some embodiments of the electromechanical actuators may include a proximity switch fixedly positioned within the housing and wherein the proximity switch is configured to detect the presence of the proximity switch target.

The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:.

The position reference system <NUM> can be any device or mechanism for monitoring a position of an elevator car and/or counter-weight, as known in the art.

Turning to <FIG>, a schematic illustration of a prior elevator car overspeed safety system <NUM> of an elevator system <NUM> is shown. The elevator system <NUM> includes an elevator car <NUM> that is movable within an elevator shaft along guide rails <NUM>. In this illustrative embodiment, the overspeed safety system <NUM> includes a pair of braking elements <NUM> that are engageable with the guide rails <NUM>. The braking elements <NUM> are actuated, in part, by operation of lift rods <NUM>. The triggering of the braking elements <NUM> is achieved through a governor <NUM>, typically located at the top of the elevator shaft, which includes a tension device <NUM> located within the pit of the elevator shaft with a cable <NUM> operably connecting the governor <NUM> and the tension device <NUM>. When an overspeed event is detected by the governor, the overspeed safety system <NUM> is triggered, and a linkage <NUM> is operated to actuate a combination of lift rods <NUM> simultaneously to cause actuation (e.g., self-engagement) of the braking elements <NUM> (e.g., safety wedges) that engage with the guide rail and cause a smooth and even stopping or braking force to stop the travel of the elevator car. As used herein the term "overspeed event" refers to an event during which a speed, velocity, or acceleration of an elevator car exceeds a predetermined threshold of the respective state of motion, and is not intended to be limited to constant speed, but rather also includes rates of change (e.g., acceleration) and also direction of travel of motion the elevator car (e.g., velocity). The linkage <NUM>, as shown, is located on the top of the elevator car <NUM> and ensures simultaneous operation of the braking elements <NUM>. However, in other configurations, the linkage may be located below a platform (or bottom) of the elevator car. As shown, various components are located above and/or below the elevator car <NUM>, and thus pit space and overhead space within the elevator shaft must be provided to permit operation of the elevator system <NUM>.

Turning now to <FIG>, schematic illustrations of an elevator car <NUM> having an overspeed safety system <NUM> in accordance with an embodiment of the present disclosure are shown. <FIG> is an isometric illustration of an elevator car frame <NUM> with the overspeed safety system <NUM> installed thereto. <FIG> is an enlarged illustration of a portion of the overspeed safety system <NUM> showing a relationship with a guide rail. <FIG> is a schematic similar to <FIG>, but with the guide rail removed for clarity of illustration.

The car frame <NUM> includes a platform <NUM>, a ceiling <NUM>, a first car structural member <NUM>, and a second car structural member <NUM>. The car frame <NUM> defines a frame for supporting various panels and other components that define the elevator car for passenger or other use (i.e., define a cab of the elevator), although such panels and other components are omitted for clarity of illustration. The elevator car <NUM> is moveable along guide rails <NUM> (shown in <FIG>), similar to that shown and described above. The overspeed safety system <NUM> provides a safety braking system that can stop the travel of the elevator car <NUM> during an overspeed event.

The overspeed safety system <NUM> includes a first safety brake <NUM>, a first electromechanical actuator <NUM>, and a controller or control system <NUM> operably connected to the first electromechanical actuator <NUM>. The first safety brake <NUM> and the first electromechanical actuator <NUM> are arranged along the first car structural member <NUM>. A second safety brake <NUM> and a second electromechanical actuator <NUM> are arranged along the second car structural member <NUM>. The control system <NUM> is also operably connected to the second electromechanical actuator <NUM>. The connection between the control system <NUM> and the electromechanical actuators <NUM>, <NUM> may be provided by a communication line <NUM>. The communication line <NUM> may be wired or wireless, or a combination thereof (e.g., for redundancy). The communication line <NUM> may be an electrical wire to supply electrical power from the control system <NUM> and an electromagnet of the first electromechanical actuator <NUM>. It will be appreciated that in alternative configurations, the communication may be a wireless communication system, both for data/information and/or wireless power transfer. It will be appreciated that the overspeed safety system <NUM>, in accordance with embodiments, can include any number of safety brakes, such as one, two, three, or more.

As shown, the control system <NUM> is located on the top or ceiling <NUM> of the car frame <NUM>. However, such position is not to be limiting, and the control system <NUM> may be located anywhere within the elevator system (e.g., on or in the elevator car, within a controller room, etc.). The control system <NUM> may comprise electronics and printed circuit boards for processing (e.g., processor, memory, communication elements, electrical buss, etc.). Thus, the control system <NUM> may have a very low profile and may be installed within ceiling panels, wall panels, or even within a car operating panel of the elevator car <NUM>. In other configurations, the control system <NUM> may be integrated into various of the components of the overspeed safety system <NUM> (e.g., within or part of the electromechanical actuator <NUM>).

The overspeed safety system <NUM> is an electromechanical system that eliminates the need for a linkage or linking element installed at the top or bottom of the elevator car. The control system <NUM> may include, for example, a printed circuit board with multiple inputs and outputs. In some embodiments, the control system <NUM> may include circuitry for a system for control, protection, and/or monitoring based on one or more programmable electronic devices (e.g., power supplies, sensors, and other input devices, data highways and other communication paths, and actuators and other output devices, etc.). The control system <NUM> may further include various components to enable control in the event of a power outage (e.g., capacitor/battery, etc.). The control system <NUM> may also include an accelerometer or other component/device to determine a speed of an elevator car (e.g., optical sensors, laser range finders, induction sensors, mechanical sensors, wheel on a rail, etc.). In such embodiments, the control system <NUM> is mounted to the elevator car, as shown in the illustrative embodiments herein.

The control system <NUM>, in some embodiments, may be connected to and/or in communication with a car positioning system, an accelerometer mounted to the car (i.e., a second or separate accelerometer), and/or to the elevator controller. Accordingly, the control system <NUM> may obtain movement information (e.g., speed, direction, acceleration) related to movement of the elevator car along an elevator shaft. The control system <NUM> may operate independently of other systems, other than potentially receiving movement information, to provide a safety feature to prevent overspeed events.

The control system <NUM> may process the movement information provided by a car positioning system to determine if an elevator car is traveling at a speed in excess of a threshold speed. If the threshold is exceeded, the control system <NUM> will trigger the electromechanical actuators and the safety brakes. The control system <NUM> will also provide feedback to the elevator control system about the status of the overspeed safety system <NUM> (e.g., normal operational position/triggered position). It will be appreciated that although referred to as an "overspeed" system, the systems may be configured to determine if an elevator car is accelerating at a rate in excess of a threshold acceleration, and the term "overspeed" is not to be limiting to merely a constant rate of motion.

Thus, the overspeed safety system <NUM> of the present disclosure enables electrical and electromechanical safety braking in the event of overspeed events. The electrical aspects of the present disclosure enable the elimination of the physical/mechanical linkages that have traditionally been employed in overspeed safety systems. That is, the electrical connections allow for simultaneous triggering of two separate safety brakes through electrical signals, rather than relying upon mechanical connections and other components such as wheels, ropes, etc..

With reference to <FIG>, details of parts of the overspeed safety system <NUM> are shown. The first electromechanical actuator <NUM> is mounted to the first car structural member <NUM> using one or more fasteners. The first electromechanical actuator <NUM> includes a magnet assembly <NUM> that is configured to magnetically engage with the guide rail <NUM>. The first electromechanical actuator <NUM> is operably connected to the control system <NUM> by the communication line <NUM>. The control system <NUM> can transmit an actuation signal to the first electromechanical actuator <NUM> (and the second electromechanical actuator <NUM>) to perform an actuation operation when an overspeed event is detected. As used herein the term "overspeed event" refers to an event during which a speed, velocity, or acceleration of an elevator car exceeds a predetermined threshold of the respective state of motion, and is not intended to be limited to constant speed, but rather also includes rates of change (e.g., acceleration) and also direction of travel of motion the elevator car (e.g., velocity). The first electromechanical actuator <NUM> will actuate a connecting rod <NUM>, by means of the magnet assembly <NUM> that is operably connected to the first safety brake <NUM>. When the connecting rod <NUM> is actuated, the first safety brake <NUM> will actuate to engage with the guide rail <NUM>, e.g., using a safety brake element <NUM>, such as a safety roller or wedge. In some embodiments, the two-part illustrated configuration may be integrated into a single unit, thus potentially eliminating the connecting rod.

In accordance with embodiments of the present disclosure, portions of the overspeed safety system are bolted or other attachment means are used to fix the components to the upright. That is, the overspeed safety system in accordance with some embodiments of the present disclosure does not float within the upright, and it is not guided by the rail. For example, in normal operation, the overspeed safety system has no contact with the guide rail. Therefore, as the elevator car floats in the front-to-back direction, the components of the overspeed safety system (e.g., a housing) move with the elevator car and the magnet assembly is sometimes closer to the blade of the guide rail and sometimes farther from the guide rail. One advantage of such approach, in accordance with embodiments of the present disclosure, is that guiding elements are not needed, and therefore, the risk of noise from the guiding elements rubbing along the rail is eliminated. Similarly, for example, there is no risk of these guiding elements wearing because they are not included in the design.

Turning now to <FIG>, schematic illustrations of an electromagnet actuator <NUM> that may incorporate embodiments of the present disclosure is shown. The electromagnet actuator <NUM> may be a part of an electromechanical actuator, as shown and described above. The electromagnet actuator <NUM>, as illustratively shown in this example embodiment, includes a magnet assembly <NUM> that is operably (and magnetically) connectable to an electromagnet assembly <NUM>. The magnet assembly <NUM> includes optional rail engagement blocks <NUM> and a magnet <NUM> (e.g., a permanent magnet or other magnetic structure/device), and may be connected to a connecting rod (not shown), as will be appreciated by those of skill in the art, or directly connected to a safety brake in a single unit. The rail engagement blocks <NUM> provide for a contact structure or surface for engaging with a guide rail of an elevator system when the electromagnet actuator <NUM> is activated to provide a stopping or braking force. The rail engagement blocks <NUM> may, optionally, include teeth or friction surfaces. The teeth of the rail engagement blocks <NUM> are configured to grip into and frictionally engage with the guide rail such that a braking force is generated. A friction surface (e.g., a grit surface) may also provide similar braking force.

In this illustrative non-limiting configuration, the electromagnet assembly <NUM> includes a coil <NUM> arranged around a core <NUM> (e.g., formed from steel or steel plates). One or more lead wires <NUM> are electrically connected to the coil <NUM> to supply electricity thereto and thus generate a magnetic field by means of the coil <NUM> and the core <NUM>. The coil <NUM> and the core <NUM> are located within a housing or other part of an elevator car (e.g., a frame) and movably mounted thereto (e.g., along springs or other biasing elements). The magnet <NUM> of the magnet assembly <NUM> is releasable from the electromagnet assembly <NUM> during a braking operation and thus cause a connecting rod to engage a safety brake of an elevator car. It will be appreciated that other configurations of electromagnetic assemblies may be employed without departing from the scope of the present disclosure (e.g., a one-piece safety configuration where the actuator is also the safety itself, with no need for a connecting rod). As shown, the coil <NUM> and the core <NUM> are mounted to a flange support <NUM> by one or more fasteners <NUM> (e.g., bolts). The biasing elements are configured to apply a biasing force against the flange support <NUM>, as will be appreciated by those of skill in the art.

<FIG> illustrates a front elevation view, illustrating details of the magnet assembly <NUM>. In particular, <FIG> illustrates the arrangement of teeth <NUM> of the rail engagement blocks <NUM>. As shown, the teeth <NUM> are arranged in columns, and in particular, three columns of teeth <NUM> are provided on each rail engagement block <NUM>. The teeth <NUM> are configured to provide a gripping or friction engagement with a guide rail during a braking operation. The teeth <NUM> will contact the material of the guide rail to generate a frictional braking force.

The illustration of <FIG> may be considered representative of a configuration of a rail engagement block. This configuration illustrates the inclusion of the three columns of teeth <NUM> which may be intentionally designed in view of operational, functional, and manufacturing considerations. The two primary considerations for formation and arrangement of the teeth are (i) maximizing the amount of tooth material (e.g., steel) in proximity to a guide rail so that a magnetic attraction of the magnetic to the guide rail can be maximized and (ii) minimizing the amount of tooth material that is actually in contact with the guide rail so that the pressures applied by the tips of the teeth can be high and the teeth can "cut into" the guide rail. That is, there is a balance between material frictional contact and magnetic contact between the magnet assembly and the guide rail to ensure a desired braking or stopping force to be generated. Alternative engagement features/surfaces may be used without departing from the scope of the present disclosure, including grit surfaces, textured surfaces, and the like.

Turning now to <FIG>, schematic illustrations of an electromechanical actuator <NUM> that may incorporate embodiments of the present disclosure are shown. <FIG> illustrates an isometric illustration of the electromechanical actuator <NUM> and <FIG> is a partial cross-sectional view of the electromechanical actuator <NUM>.

The electromechanical actuator <NUM> includes a first housing <NUM> and a second housing <NUM> that are fixedly connected together. Although shown, two separate housing components <NUM>, <NUM> are configured to form a housing assembly <NUM>. In alternative embodiments, the housing assembly <NUM> may be a single body, structure, or component that has substantially the same shape, structure, and configuration as the illustrative first and second housings <NUM>, <NUM>. The electromechanical actuator <NUM> further includes an electromagnet assembly <NUM> and a magnet assembly <NUM>. As shown in <FIG>, the electromagnet assembly <NUM> may be housed between the first housing <NUM> and the second housing <NUM> and the magnet assembly <NUM> is housed within a track <NUM> defined by the second housing <NUM>. In operation, the magnet assembly <NUM> may move along and within the track <NUM>.

The electromagnet assembly <NUM> is a preformed structure that includes a coil and a core (e.g., laminated core, machined piece(s), etc.). Although shown and described as a laminated core, other core structures are possible without departing from the scope of the present disclosure. For example, in some embodiments, the core may be steel cores (e.g., formed from machined pieces) or ferrite cores. The electromagnet assembly <NUM> may be moveably mounted within the housing <NUM>, <NUM> along one or more guides <NUM> and be biased to a rest position by one or more biasing elements <NUM> along the guides <NUM>. Additionally, lead wires electrically connected to the coil of the electromagnet assembly <NUM> may be securely retained or installed within the unitary structure. The electromagnet assembly <NUM> includes an encapsulating body <NUM> which contains the components of the electromagnet assembly <NUM>. The encapsulating body <NUM> may be, for example, a preformed body, a cast body, a molded structure, or a potted structure that has the components of the electromagnet assembly <NUM> embedded therein (e.g., coil, laminated core, lead wire, etc.). In some embodiments, the encapsulating body <NUM> may be preformed and the components installed therein and in other embodiments, the encapsulating body <NUM> may be formed around the components. The lead wire may electrically connect to an electrical connector <NUM>. The electrical connector <NUM> may be fixedly attached to or mounted to the first housing <NUM> and can provide for electrical connection between the electromagnet assembly <NUM> and an electrical source of the control system (e.g., as shown and described above).

The first housing <NUM> is configured to be mounted to or affixed to a portion of an elevator car, such as a frame. The second housing <NUM> is configured to be a portion of the structure that is moveable along (e.g., adjacent or relative to) a guide rail of an elevator system. That is, the second housing <NUM> defines a portion of the electromechanical actuator <NUM> that is adjacent to or proximate the guide rail. This results in the magnet assembly <NUM> being arranged and retained within the track <NUM> of the second housing <NUM> between material of the first and/or second housing <NUM>, <NUM> and the guide rail. It will be appreciated that the second housing <NUM> preferably does not contact the guide rail. That is, although the elevator car and electromechanical actuator <NUM> may float away from the guide rail (e.g., relative movement/motion), the dimensions of the magnet assembly <NUM> are such that the magnet assembly <NUM> never leaves the track <NUM>.

As shown in <FIG>, the electromagnet assembly <NUM> is an encapsulated component of the electromechanical actuator <NUM>. However, as described herein, other components, such as the magnet assembly <NUM> may be alternatively or additionally encapsulated.

For example, turning now to <FIG>, a schematic illustration of an electromechanical actuator <NUM> that may incorporate embodiments of the present disclosure is shown. The electromechanical actuator <NUM>, as shown, includes a unitary formed housing <NUM> similar to that shown and described above (but in single-body form). The electromechanical actuator <NUM> includes an encapsulated electromagnet assembly <NUM> and an encapsulated magnet assembly <NUM>. The encapsulated electromagnet assembly <NUM> is housed in a portion of the housing <NUM> and translatable or moveable along guides <NUM>, similar to that described above. The encapsulated magnet assembly <NUM> is housed within a track <NUM> defined by a portion of the housing <NUM>. In operation, the encapsulated magnet assembly <NUM> may move along and within the track <NUM>.

Similar to the described encapsulated electromagnet assemblies described above, the components of the magnet assembly of the electromechanical actuator <NUM> are encased within a material to protect such components and improve part life. As shown, the encapsulated magnet assembly <NUM> includes an encapsulating body <NUM> that houses a magnet <NUM>, which may include one or more rail engagement blocks. The encapsulating body <NUM> also houses a connector pin <NUM> that is configured to engage with a connecting rod to enable actuation of a safety brake when the encapsulated magnet assembly <NUM> moves upward along the track <NUM>. The formation and structure of the encapsulated magnet assembly <NUM> may be substantially similar to that of the encapsulated electromagnet assemblies described above. That is, similar materials and/or manufacturing processes may be employed to form the encapsulated magnet assembly <NUM>.

The connector pin <NUM> may be part of a component integrator <NUM> that allows for different locations/arrangements of connection to a connecting rod. Depending on a specific application and arrangement of parts (e.g., of the safety brake) some safeties lend themselves to lifting from the top of a wedge (e.g., most symmetric safeties) and others lend themselves to lifting from a face of a wedge (e.g., most asymmetric safeties). The preformed structure of the component integrator <NUM> permits different connection points to the connector pin <NUM>, and thus enables greater versatility as compared to prior configurations.

The triggering of the electromechanical actuators may be by operation of a proximity switch target. The proximity switch target is configured to detect the location of the magnet assembly (e.g., on the electromechanical actuator as compared to engaged with a rail) by sensing a target (e.g., steel) that is arranged in proximity to the magnet assembly. In accordance with embodiments of the present disclosure, a proximity switch target is encapsulated within the encapsulated magnet assembly. For example, and without limitation, the proximity switch target may be installed or inserted using an injection molding process. In such processes, the components of the encapsulated magnet assembly and the proximity switch target are placed within a mold and plastic is injected into the mold in order to encapsulate the components and the proximity switch target within a single body.

Turning now to <FIG>, schematic illustrations of an electromechanical actuator <NUM> in accordance with an embodiment of the present disclosure are shown. The electromechanical actuator <NUM>, as shown, includes a unitary formed housing <NUM>. The electromechanical actuator <NUM> includes an encapsulated electromagnet assembly <NUM> and an encapsulated magnet assembly <NUM>. The encapsulated electromagnet assembly <NUM> is housed in a portion of the housing <NUM> and translatable or moveable along guides <NUM>. The encapsulated magnet assembly <NUM> is housed within a track <NUM> defined by a portion of the housing <NUM>. In operation, the encapsulated magnet assembly <NUM> may move along and within the track <NUM>.

The encapsulated magnet assembly <NUM> includes a component integrator <NUM> configured to enable connection between the encapsulated magnet assembly <NUM> and a connecting rod <NUM>. The component integrator <NUM> includes a magnet assembly extension <NUM> and a connector pin <NUM>. When the encapsulated magnet assembly <NUM> engages with a guide rail, the encapsulated magnet assembly <NUM> will cause actuation of the connecting rod <NUM> to in turn actuate a safety brake.

It may be required to know the state or position of the encapsulated magnet assembly <NUM> relative to the housing <NUM>, a guide rail, and/or the encapsulated electromagnet assembly <NUM>. To detect the position of the encapsulated magnet assembly <NUM>, a proximity switch <NUM> may be mounted to or otherwise attached to one of the guides <NUM> of the housing <NUM>. It will be appreciated that in other embodiments, the proximity switch may be attached or affixed in another location and/or to another component of the housing <NUM> and/or other part of the electromechanical actuator <NUM>, and the configuration is provided for illustrative and explanatory purposes only. The proximity switch <NUM> has a fixed position relative to the housing <NUM> such that detection of a component moving relative to the proximity switch <NUM> may be detected.

In accordance with the present embodiment, the encapsulated magnet assembly <NUM> includes an encapsulated proximity switch target <NUM>. The proximity switch target <NUM> may be a metallic component that may be magnetically detected (e.g., steel, aluminum, or other metals and/or materials). Further, proximity switch targets, in accordance with embodiments of the present disclosure, may have any geometric shape, but may, preferably, be cylindrical (e.g., puck or cylinder), although other shapes, such as squared, rectangular, circular, triangular, hexagonal, polygonal, etc., may be used without departing from the scope of the present disclosure. In other embodiments, as described herein, the proximity switch target may have a tab-like configuration. In accordance with embodiments of the present disclosure, the encapsulated proximity switch target <NUM> can achieve robustness because variation in the target location due to tolerances can be minimized. Further, by arranging the proximity switch target <NUM> at a location remote from, yet attached to the encapsulated magnet assembly <NUM>, a separation between the metallic rail engagement blocks of the encapsulated magnet assembly <NUM> from the proximity switch target <NUM> may ensure that the magnetic field of the magnet of the encapsulated magnet assembly <NUM> does not influence an ability of the proximity switch <NUM> to detect the proximity switch target <NUM>.

Turning now to <FIG>, schematic illustrations of an encapsulated magnet assembly <NUM> in accordance with an embodiment of the present disclosure are shown. The encapsulated magnet assembly <NUM> includes a magnet <NUM> and rail engagement blocks <NUM> housed within an encapsulating body <NUM>. The rail engagement blocks <NUM> may include teeth or friction surfaces, as will be appreciated by those of skill in the art. The encapsulating body <NUM> may be formed from plastic, thermoplastic, thermoset, epoxy, resin, and the like. The encapsulating body <NUM> is formed from a non-magnetic material to provide structural support and housing while minimizing interference with operation of an electromechanical actuator to which the encapsulated magnet assembly <NUM> may be a part.

<FIG> illustrate the encapsulated magnet assembly <NUM> as a complete component and <FIG> illustrates the components of the encapsulated magnet assembly <NUM> without the encapsulating body <NUM>. The encapsulating body <NUM> includes a target extension <NUM> for supporting, retaining, or otherwise holding a proximity switch target <NUM>. It is noted that, in some embodiments, the target extension <NUM> may be configured to removably attach or retain the proximity switch target <NUM>. In other embodiments, the proximity switch target <NUM> may be permanently encapsulated within the material of the target extension <NUM>. A magnet assembly extension <NUM> is attached to the encapsulated magnet assembly <NUM> by one or more fasteners <NUM>. The fasteners <NUM> may securely affix the magnet assembly extension <NUM>, the rail engagement blocks <NUM> and the magnet <NUM> together. The magnet assembly extension <NUM> is configured to connect to a connecting rod that, in turn, is connected to a safety brake to enable actuation of the safety brake, as described above.

The target extension <NUM> of the encapsulating body <NUM> is sized, shaped, and configured to position the proximity switch target <NUM> relative to the rest of the components of the encapsulated magnet assembly <NUM> in addition to positioning it relative to a proximity switch of an electromechanical actuator, such as shown in <FIG>. A length of the target extension <NUM> is selected to ensure that the magnet <NUM> does not interfere with operation of the proximity switch interacting with the proximity switch target <NUM>. In some non-limiting embodiments, the length of the target extension may be set to a minimum of about <NUM> from the magnet, although other separation distances may be used without departing from the scope of the present disclosure. For example, in some embodiments, the proximity switch target may be positioned closer than <NUM> from the magnet, and in other embodiments, the separation distance may be larger than <NUM>, such as <NUM>, <NUM>, or even <NUM> or greater.

Turning now to <FIG>, schematic illustrations of an encapsulated magnet assembly <NUM> in accordance with an embodiment of the present disclosure are shown. The encapsulated magnet assembly <NUM> includes a magnet <NUM> and rail engagement blocks <NUM> housed within an encapsulating body <NUM>. The encapsulating body <NUM> includes a component integrator <NUM> that provides for a target extension similar to that described above, for supporting, retaining, or otherwise holding a proximity switch target <NUM>. In this embodiment, the connection with a connecting rod is provided by a connecting pin <NUM> that is housed within the component integrator <NUM>. Similar to that described above, the proximity switch target <NUM> is retained at a fixed position relative to the rest of the encapsulated magnet assembly <NUM> within the component integrator <NUM>. As such, a target extension in this embodiment is provided by the component integrator <NUM>, or stated another way, the component integrator <NUM> in this embodiment includes the target extension described above. The encapsulating body <NUM> is formed of non-magnetic material that is formed and arranged to reduce, minimize, and/or eliminate magnetic interference with operation of a proximity switch and the proximity switch target <NUM>.

Turning now to <FIG>, an alternative configuration of a magnet assembly <NUM> in accordance with an embodiment of the present disclosure is shown. The magnet assembly <NUM> can be encapsulated with an encapsulating body, although such feature is not show for clarity. The magnet assembly <NUM> includes a magnet <NUM>, rail engagement blocks <NUM>, and a component integrator <NUM>. The component integrator <NUM> is configured to attach a connector pin <NUM> and a proximity switch target <NUM> to the magnet assembly <NUM>. In this configuration, the proximity switch target <NUM> is housed within a target housing <NUM> to provide magnetic insulation from the metal of the magnet assembly <NUM>.

Turning now to <FIG>, an alternative configuration of a magnet assembly <NUM> in accordance with an embodiment of the present disclosure is shown. The magnet assembly <NUM> includes an encapsulating body <NUM> having a magnet <NUM>, rail engagement blocks <NUM>, and a magnet assembly extension <NUM> for connecting to a connecting rod. A proximity switch target <NUM> extends from the magnet assembly <NUM>, and in this configuration is a tab-like structure or part.

<FIG> illustrates an alternative tab-style configuration of a magnet assembly <NUM>. The magnet assembly <NUM> includes an encapsulating body <NUM> having a magnet <NUM>, rail engagement blocks <NUM>, and a magnet assembly extension <NUM> for connecting to a connecting rod. A proximity switch target <NUM> extends from the magnet assembly <NUM>, and in this configuration is a tab-like structure or part.

In each of the above described embodiments, and in accordance with embodiments of the present disclosure, a proximity switch target is fixedly attached or connected to a magnet assembly in order to position the proximity switch target relative to the components thereof. The position of the proximity switch target is selected for detection by a proximity switch of an electromechanical actuator and to minimize or prevent interference from other metallic and/or magnetic components.

Accordingly, in accordance with embodiments of the present disclosure, electromechanical systems may incorporate one or more improved magnet assemblies, as shown and described above. Embodiments of the present disclosure provide for targets to be detected by proximity switches of electromechanical actuators. The targets may be encapsulated within plastic or other non-magnetic materials to achieve robustness with respect to target location, tolerances, and the like. Further, embodiments of the present disclosure can minimize or eliminate magnetic interference from magnetic components of the magnet assemblies by separating the position of the target relative to the rail engagement blocks and/or magnet while maintaining the target in a fixed position relative to the magnet assembly.

The terms "about" and "substantially" are intended to include the degree of error associated with measurement of the particular quantity and/or manufacturing tolerances based upon the equipment available at the time of filing the application.

Claim 1:
A magnet assembly (<NUM>) of an electromechanical assembly for an elevator system (<NUM>), the magnet assembly (<NUM>) comprising:
a magnet (<NUM>);
at least one rail engagement block (<NUM>);
an encapsulating body (<NUM>) encapsulating the magnet (<NUM>) and the at least one rail engagement block (<NUM>);
characterised in that:
the encapsulating body (<NUM>) is formed form a non-magnetic material; and
the magnet assembly further comprises:
a target extension (<NUM>) formed from the material of the encapsulating body (<NUM>) and extending away from the magnet (<NUM>) and the at least one rail engagement block (<NUM>); and
a proximity switch target (<NUM>) held within the target extension (<NUM>).