Frictionless Electronic Safety Actuator

Abstract

A frictionless electronic safety actuator (100) for use in an elevator system includes at least one electromagnet (110) and a magnetic plate (120) attached to a connection arrangement (190). The connection arrangement (190) is configured to connect the magnetic plate (120; 220) to an actuatable link (80) so as to move a safety brake (24) into frictional engagement with an elevator guide rail (20). The at least one electromagnet (110) is operable to selectively generate a magnetic force that acts on the magnetic plate (120) to displace the magnetic plate (120) and thereby move the connection arrangement (190) to actuate the link (80) without the magnetic plate (120) frictionally engaging the elevator guide rail (20).

Description

Technical Field

[0001] The present disclosure relates to a frictionless electronic safety actuator for use in elevator systems. Background Art

[0002] It is known in the art to install safety brakes on elevator components that move along guide rails to quickly and safely stop the elevator components, particularly in emergency situations. In many elevator systems, the elevator car is lifted by a tensioning member whose movement is guided by a pair of guide rails. Typically, a speed governor is used to monitor the speed of the elevator car. Standard safety regulations require such elevator systems to include an emergency braking device (commonly known as a safety brake, "safety device," or "safety element") that can stop the elevator car's downward movement by grabbing the guide rails even if the tensioning member breaks. Safety brakes can also be installed on the counterweight or other components that move along the guide rails.

[0003] Instead of relying solely on a mechanical governor, electronic safety actuators (ESAs) are now commonly used to trigger the safety brake. ESAs typically activate the safety brake by dragging a magnet (permanent magnet or electromagnet) against the guide rail, using friction to pull up on a linkage attached to the safety brake. Relying on frictional interaction between the magnet and the guide rail presents numerous problems, particularly in high-rise elevator systems, as the interaction causes wear on the rail and can lead to wear and debris accumulation. Any degradation of the guide rail's condition is a concern, as it impacts the safety of the entire elevator system.

[0004] Therefore, there is a need for improved electronic safety actuation of safety brakes. Summary of the Invention

[0005] According to a first aspect of the present disclosure, there is provided a frictionless electronic safety actuator for use in an elevator system, comprising:

[0006] at least one electromagnet and a magnetic plate attached to the connection arrangement;

[0007] wherein the connection arrangement is configured to connect the magnetic plate to an actuatable link so as to move the safety brake into frictional engagement with the elevator guide rails; and

[0008] At least one of the electromagnets is operable to selectively generate a magnetic force acting on the magnetic plate to displace the magnetic plate and thereby move the connecting arrangement to actuate the connecting rod without the magnetic plate frictionally engaging the elevator guide rail.

[0009] It will be appreciated that, according to the present disclosure, the frictionless electronic safety actuator provides actuation of the safety brake without the assistance of frictional contact between the electronic safety actuator and the guide rails. This provides the following advantages: the actuation of the safety brake is not affected by the state of the elevator guide rails, and therefore, debris from the elevator hoistway or dust from the elevator guide rails cannot interfere with the actuation of the frictionless electronic safety actuator.

[0010] It will be further understood that the location of the frictionless electronic safety actuator is no longer limited by the need to contact the guide rails and can be positioned anywhere on the elevator component where the linkage can then actuate the safety brake. Thus, in some examples, the components of the frictionless electronic safety actuator do not make frictional contact with the elevator guide rails.

[0011] Those skilled in the art will appreciate that the connection arrangement can be any type of connection between the magnetic plate and the connecting rod, and while certain examples of types of connection arrangements are disclosed herein, these are by way of example only. The movement of the connecting rod can be a vertical movement intended to push or pull the safety brake into engagement with the elevator guide rails. In other examples, the movement of the connecting rod can be in any direction to move the safety brake into engagement with the elevator guide rails.

[0012] According to a first set of examples, the connection arrangement is configured to convert horizontal displacement of the magnetic plate into vertical movement of the connecting rod. The connection arrangement may be in the form of a scissor mechanism that converts horizontal displacement of the magnetic plate into vertical movement of the connecting rod. Such an arrangement may be advantageous in locations where there is limited vertical space for placing the frictionless electronic safety actuator relative to the safety brake.

[0013] In some examples of the first group of examples, the connection arrangement includes a compression spring arrangement configured to convert horizontal displacement of the magnetic plate into vertical movement of the connecting rod; the compression spring arrangement generates a spring bias to return to a relaxed state, which actuates vertical movement of the connecting rod to move the safety brake into frictional engagement with the elevator guide rail. The use of a compression spring arrangement allows for the introduction of a bias, wherein the spring biases the magnetic plate into a position in which, when the connection arrangement is free to move, the connecting rod actuates the safety brake. This can be achieved by removing the magnetic force, wherein an electromagnet can selectively operate the magnetic force to maintain the magnetic plate in a position in which the connecting rod is not actuated, i.e., a normal operating position. When the magnetic field is removed or reversed, the magnetic plate can be pulled into a position actuating the connecting rod by the bias of the compression spring arrangement. In some examples, the compression spring arrangement includes at least one leaf spring. In some examples, the compression spring arrangement includes a buckling spring.

[0014] In some examples of the first group of examples, the connection arrangement includes a plurality of leaf springs connected in series to form an accordion-like member in a vertical direction, with one end fixed and one end movable in the vertical direction; and a connecting rod connection point located at the movable end of the accordion-like member. Optionally, the plurality of leaf springs may have a relaxed state biased toward a position that actuates the connecting rod, and during normal operation, the magnetic force between the at least one electromagnet and the magnetic plate may pull the plurality of leaf springs in a horizontal direction against their bias. Optionally, the plurality of leaf springs comprise thin metal sheet material. Such leaf springs may be able to deform easily without exceeding their yield strength, yet be able to provide sufficient spring bias and displacement distance. It will be appreciated that the use of multiple leaf springs allows a small horizontal deflection to be converted into a larger vertical deflection, which can provide a large actuation distance for the connecting rod.

[0015] In some examples of the first group of examples, vertical movement of the plurality of leaf springs is guided, such that first sides of the plurality of leaf springs are fixed in the horizontal direction and guided in the vertical direction, and second sides of the plurality of leaf springs are guided in the vertical direction and movable in the horizontal direction; wherein the second sides of the plurality of leaf springs are attached to a magnetic plate, and the horizontal movement is determined by operation of at least one electromagnet. This fixing helps prevent loss of vertical movement due to spring imbalance, thereby improving the efficiency of transferring spring force from the horizontal direction to the vertical direction.

[0016] In some examples of the first group of examples, at least one electromagnet is operable to remove or reverse the magnetic field so as to displace the magnetic plate. It will be understood that this may mean triggering of the frictionless electronic safety actuator. By reducing the horizontal deflection, the plurality of leaf springs may be allowed to return to their relaxed state, wherein the reduction in the horizontal direction is converted into movement in the vertical direction, so that the actuating link is actuated. This trigger state is the natural state of the spring (a plurality of leaf springs or any other form of compression spring), which has the advantage of making the movement to the trigger position as efficient as possible. In addition, it will be understood that this may introduce a fault protection, since the frictionless electronic safety actuator may automatically trigger the safety brake if at least one electromagnet loses power.

[0017] In some examples of the first set of examples, the magnetic plate includes at least one permanent magnet. By using at least one permanent magnet, it will be appreciated that the power requirements for the frictionless electronic safety actuator can be significantly reduced, as continuous power is not required to deactivate the linkage, but rather only a small amount of power is required to release the magnetic plate. Optionally, when no current is running through the electromagnet, the magnetic attraction between the permanent magnet and the electromagnet is greater than the spring force of the plurality of leaf springs.

[0018] In the example where the magnetic plate includes at least one permanent magnet, the arrangement is similar to that of many conventional ESA systems (although now actuation is performed in a frictionless manner). This means that existing ESA layouts can be retained. It will be appreciated that the operation of the at least one electromagnet can also be similar to that of many conventional ESA systems, and thus can allow for an easy upgrade to a frictionless ESA as disclosed herein.

[0019] In some examples of the first set of examples, at least one electromagnet is operable to generate a magnetic field to repel the magnetic plate. It will be appreciated that when the magnetic plate additionally includes at least one permanent magnet, a magnetic field is required to move the magnetic plate from the normal operating position to the triggered position. This may be assisted by the spring bias of the compression spring arrangement, thereby effectively actuating the connecting rod.

[0020] In some examples of the first set of examples, the at least one electromagnet is operable to generate a magnetic field to reposition the magnetic plate; wherein the magnetic plate moves in a horizontal direction against the bias of the compression spring arrangement. It will be understood that such movement can move the magnetic plate from the triggered position back to the normal operating position. Optionally, during normal operation, the magnetic plate can be held in place by the magnetic force of the at least one electromagnet.

[0021] In a first set of examples, the connection arrangement is configured to convert horizontal movement of the magnetic plate into vertical movement of the connecting rod. Advantageously, a small horizontal movement can be converted into a larger vertical movement to actuate the connecting rod. Some configurations of elevator components and their safety brakes may have spatial constraints, and this first example of a frictionless electronic safety actuator is more suitable for such spatial constraints. However, there are various alternative connection arrangements suitable for use in a frictionless electronic safety actuator. This article provides a second set of examples of embodiments of a frictionless electronic safety actuator.

[0022] According to a second set of examples, at least one electromagnet is configured to vertically displace the magnetic plate and its attached connection arrangement to directly displace the connecting rod in the vertical direction. It will be appreciated that such an arrangement can actuate the connecting rod and activate the safety brake in an uncomplicated manner. In this second set of examples, the connection arrangement can be relatively simple, with fewer parts that can cause errors.

[0023] In some examples of the second set of examples, the single electromagnet is configured to move the magnetic plate in a vertical direction to vertically displace the connecting rod.

[0024] In some examples of the second set of examples, the pair of electromagnets are positioned to be vertically displaced such that a magnetic force is selectively generated to vertically displace the magnetic plate between the two electromagnets such that the connecting rod is actuated.

[0025] It will be appreciated that the electromagnets can be configured to push the magnetic plate upward in a vertical direction to vertically displace the connecting rod, and / or the electromagnets can be configured to push the magnetic plate upward in a vertical direction to vertically displace the connecting rod. It will also be appreciated that using a pair of magnets to displace the magnetic plate between them will require smaller electromagnets and may require less power than a single electromagnet. The combined magnetic field generated by the paired electromagnets can be more easily adjusted to control the movement of the magnetic plate and allow for more efficient actuation of the connecting rod.

[0026] In some examples of the second set of examples, the magnetic plate is displaced toward a stopper, wherein the stopper is resiliently mounted. The resilient mounting of the stopper can allow for overtravel in the displacement of the magnetic plate, which can allow for greater tolerances in the connection of the connecting rod to the safety brake, thereby accommodating variable actuation distances. The stopper can be a magnetic plate, a permanent magnet, or an electromagnet.

[0027] In some examples of the second set of examples, the resilient mounting member of the stop member is arranged to relax to assist in resetting the magnetic plate. Optionally, the resilient mounting member may be a spring.

[0028] In some examples of the second set of examples, at least one electromagnet is operable to generate a magnetic field to displace the magnetic plate vertically upward, i.e., to actuate the connecting rod. It will be appreciated that displacement of the magnetic plate can be caused by various combinations of magnetic fields, depending on the number of electromagnets used in the frictionless electronic safety actuator. If a single electromagnet is used at the bottom, a repulsive magnetic field can be generated to repel the magnetic plate upward. If a single electromagnet is used at the top, an attractive magnetic field can be generated to attract the magnetic plate upward. If a pair of electromagnets is used, a combination of fields can be generated to cause upward movement.

[0029] In some examples of the second set of examples, at least one electromagnet is operable to remove or reverse the magnetic field to displace the magnetic plate. It will be appreciated that the magnetic plate can fall back to its normal operating position under the force of gravity. This means that resetting the frictionless electronic safety actuator is easily performed without external influence. The magnetic plate can be actively displaced downward by operation of the at least one electromagnet, which assists the magnetic plate's natural movement due to gravity.

[0030] In some examples of the second set of examples, the magnetic plate is a permanent magnet. The permanent magnet can generate a larger magnetic field, facilitating interaction between the magnetic plate and the at least one electromagnet. Consequently, less power can be required from the at least one electromagnet to move the magnetic plate into the trigger position. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Certain preferred examples of the present disclosure will now be described, by way of example only, and with reference to the accompanying drawings, in which:

[0032] Figure 1An example of an elevator system employing a mechanical speed governor is shown;

[0033] Figure 2A shows a schematic side view of a frictionless electronic safety actuator during normal operation of an elevator according to a first example;

[0034] Figure 2B shows a schematic side view of a frictionless electronic safety actuator in a tripped position according to a first example;

[0035] Figure 3 shows a schematic side portion of a frictionless electronic safety actuator connected to an elevator safety brake in a tripped position according to a first example;

[0036] Figure 4 shows a schematic side view of a frictionless electronic safety actuator connected to a safety brake during normal operation of an elevator according to a second example;

[0037] Figure 5 shows a schematic side view of a frictionless electronic safety actuator connected to a safety brake in a semi-tripped position according to a second example; and

[0038] Figure 6 A schematic side view of an electronic safety actuator connected to a safety brake according to a second example is shown in a tripped position. DETAILED DESCRIPTION

[0039] Figure 1 An elevator system is shown, generally indicated at 10. Elevator system 10 includes a cable or belt 12, a car frame 14, an elevator car 16, roller guides 18, guide rails 20, a governor 22, and a pair of safety brakes 24 mounted on elevator car 16. Governor 22 is mechanically coupled by a connecting rod 26, a rod 28, and a lifting rod 30 to actuate safety brake 24. Governor 22 includes a governor pulley 32, a rope ring 34, and a tensioning pulley 36. Cable 12 is connected to car frame 14 and a counterweight (not shown) inside the hoistway. Elevator car 16, attached to car frame 14, is moved up and down within the hoistway by force transmitted to car frame 14 by cable or belt 12 from an elevator drive (not shown) in a machine room, typically located at the top of the hoistway. Roller guides 18 are attached to car frame 14 to guide elevator car 16 up and down within the hoistway along guide rails 20. A governor pulley 32 is mounted at the upper end of the hoistway. A rope eye 34 is partially wound around the governor pulley 32 and partially wrapped around a tensioning pulley 36 (located at the bottom end of the hoistway in this example). The rope eye 34 is also connected to the elevator car 16 at the rod 28 to ensure that the angular velocity of the governor pulley 32 is directly related to the speed of the elevator car 16.

[0040] exist Figure 1 In the elevator system 10 shown in FIG, if the elevator car exceeds a set speed while traveling inside the hoistway, the governor 22, a machine brake (not shown) located in the machine room, and a safety brake 24 function to stop the elevator car 16. If the elevator car 16 reaches an overspeed condition, the governor 22 first triggers to engage a switch, which in turn cuts off power to the elevator drive and releases the machine brake to prevent movement of the drive pulley (not shown), thereby preventing movement of the elevator car 16. However, if the elevator car 16 continues to experience an overspeed condition, the governor 22 may then function to trigger the safety brake 24 to prevent movement of the elevator car 16 (i.e., an emergency stop). In addition to engaging the switch to release the machine brake, the governor 22 also releases a clutch device that grabs the governor rope 34. The governor rope 34 is connected to the safety brake 24 via a mechanical linkage 26, a rod 28, and a lifting rod 30. As elevator car 16 continues its descent, governor rope 34, now blocked from movement by actuated governor 22, pulls on operating lever 28. Operating lever 28 actuates safety brake 24 by moving connecting rod 26 connected to lifting rod 30, and lifting rod 30 causes safety brake 24 to engage guide rails 20 to stop elevator car 16.

[0041] It will be understood that although a roped elevator is described herein, the examples of the electronic safety actuator described herein will function equally well with ropeless elevator systems, such as hydraulic systems and systems with linear motors.

[0042] While mechanical governor systems are still used in many elevator systems, other elevator systems are now implementing electronically actuated systems to trigger the emergency safety brake 24. Most of these electronically actuated systems utilize friction between a magnet and the guide rail 20 to then mechanically actuate a linkage to engage the safety brake 24. Examples of electronic safety actuators are disclosed herein that do not utilize friction against the guide rail 20 to actuate the safety brake 24.

[0043] Figure 2A A first example of a frictionless electronic safety actuator 100 during normal elevator operation is shown, and Figure 2B A first example of a frictionless electronic safety actuator 100 is shown in a triggered position. Figure 3A triggered frictionless electronic safety actuator 100 is shown in a tripped position positioned above a safety brake 24. The frictionless electronic safety actuator 100 comprises at least one electromagnet 110 and a magnetic (e.g., steel) plate 120. The magnetic plate 120 is attached to a connection arrangement 190 comprising a plurality of leaf springs 130 connected in series to form a concertina 135, the connection arrangement having a fixed side 150 with a fixing hole 180, a movable side 140, a fixed bottom plate 170, and a movable top plate 160 with a link connection point 195.

[0044] exist Figure 2A 、 2B In the example shown in Figures 3 and 4, a plurality of leaf springs 130 are assembled together in the form of a plurality of elliptical leaf springs, which are connected in series at their vertices to form an accordion-shaped member 135. The first side of each leaf spring 130 is fixed on the horizontal axis but movable on the vertical axis, and the second side opposite the first side is movable on both the horizontal and vertical axes. The first side of each leaf spring 130 is connected to a fixed side 150 of a connecting arrangement 190 via a guide (not shown) to allow movement in the vertical direction. The fixed side 150 is configured to be attached to an elevator component, i.e., the elevator car 16 or the counterweight, via a fixing hole 180. The second side of each leaf spring 130 is connected to a movable side 140 of the connecting arrangement 190 via a guide (not shown), which is attached to a magnetic plate 120. In some examples, the magnetic plate 120 is a steel plate. The accordion-shaped member 135 of the leaf spring 130 is also attached to a fixed bottom plate 170 and a movable top plate 160, both of which extend horizontally between the movable side 140 and the fixed side 150. The fixed bottom plate 170 is fixed relative to the fixed side 150, and the top plate 160 moves vertically with the movement of the plurality of leaf springs 130. The connecting rod 80 ( Figure 2A and Figure 2B 160 at the connecting rod connection point 195. Figure 3 As shown in , the connecting rod 80 connects the frictionless electronic safety actuator 100 to the safety brake 24 , for example, the safety brake 24 mounted below the electronic safety actuator 100 .

[0045] The plurality of leaf springs 130 are designed to deform easily without exceeding their yield strength while still being able to provide the required actuation distance and spring force capable of actuating the connecting rod 80. In some examples, the plurality of leaf springs 130 comprise thin metal sheet plates. Various alternative compression spring arrangements are contemplated, such as an accordion-like member using buckling springs instead of leaf springs. In some examples, a single leaf spring may be used.

[0046] The at least one electromagnet 110 is positioned relative to the magnetic plate 120 such that when the at least one electromagnet 110 is operated, the generated magnetic field acts on the magnetic plate 120. Figure 2A 、 2B In the examples of Figures 1 and 3, the electromagnet 110 is positioned horizontally adjacent to the magnetic plate 120. The electromagnet 110 is shown as having an E-shaped core with paired coils, but of course it may take any suitable form, such as a straight core with a single coil or more than two coils.

[0047] Figure 2A The frictionless electronic safety actuator 100 is shown during normal elevator operation. In this example, the electromagnet 110 operates to generate a magnetic field that acts with a horizontal magnetic force on the magnetic plate 120, pulling the movable side 140 of the connecting arrangement 190 toward the electromagnet 110 and, as a result, deflecting the second side of the accordion 135 of the plurality of leaf springs 130 in a horizontal direction. As indicated by the force arrows, the electromagnet 110 acts to pull the magnetic plate 120 and the movable side of the accordion 135 of the plurality of leaf springs 130 horizontally against the force of the plurality of leaf springs 130, maintaining the accordion 135 in this position during normal elevator operation. Because the leaf springs 130 are attached together at their apexes in an accordion-type arrangement, this horizontal pulling combined with the vertical compression of the plurality of leaf springs 130 creates a combined effect.

[0048] Figure 2B The frictionless electronic safety actuator 100 is shown in a tripped position and can be used to actuate the safety brake 24 ( Figure 1 ). In this example, the electromagnet 110 operates to remove the magnetic field acting on the magnetic plate 120, thereby allowing the movable side 140 of the connecting arrangement 190 to be pulled away from the electromagnet 110 by the accordion-like member 135 of the plurality of leaf springs 130 applying a vertical force to return to its relaxed state, thereby reducing its horizontal deflection. This horizontal movement of the magnetic plate 120 is shown by the arrows. This produces a vertical movement in the top plate 160, which in turn moves the link connection point 195, causing the link 80 to be pulled upward ( Figure 2A and 2B ) to actuate the safety brake 24.

[0049] In this example, when the elevator is in normal operation ( Figure 2A ), the electromagnet 110 generates an attractive force on the magnetic plate 120. When it is necessary to engage the safety brake 24, the electromagnet 110 stops generating an attractive force, and the force of the plurality of leaf springs 130 actuates the connecting rod to pull the safety brake 24. This acts as a failsafe in the event of a power outage, because when the electromagnet 110 loses power, the safety brake 24 will be automatically actuated.

[0050] In some examples, at least one electromagnet 110 operates to actively repel the magnetic plate 120, providing additional force to the force of the plurality of leaf springs 130 to return to their relaxed state. This can expedite the process of actuating the safety brake 24.

[0051] To reset the frictionless electronic safety actuator 100 , the at least one electromagnet 110 operates to generate a magnetic force to horizontally displace the magnetic plate 120 back to its original position against the bias of the accordion 135 of the plurality of leaf springs 130 .

[0052] exist Figure 2A and 2B In the example shown in FIG, the electromagnet 110 operates to generate an attractive magnetic field that acts on the magnetic plate 120 to pull the magnetic plate 120 back to its normal operating position. This pulls the plurality of leaf springs 130 into a deflected position.

[0053] Figure 3 An example of a frictionless electronic safety actuator 100 positioned above a safety brake 24 in a tripped position is shown. A connecting rod 80 is shown attached to a top plate 160 at one end at a connecting rod connection point 195 and to the safety brake 24 at the other end. The connecting rod has actuated the safety brake 24. The illustrated connection arrangement 190 includes a plurality of leaf springs 130, a fixed side 150 having a fixing hole 180, a movable side 140, a fixed base plate 170, a top plate 160, and a connecting rod connection point 195. In this example, the magnetic (e.g., steel) plate 120 also includes at least one permanent magnet 122.

[0054] exist Figure 3 In the example shown in FIG, the magnetic plate 120 includes at least one permanent magnet 122. The permanent magnet 122 acts to assist in attracting the magnetic plate 120 to the at least one electromagnet 110. In this example, no constant current is required in the at least one electromagnet 110 during normal operation of the elevator, and the at least one electromagnet 110 operates only to provide a force to help the plurality of leaf springs 130 return to their relaxed state and actuate the safety brake 24.

[0055] exist Figure 3 In the example shown, to reset the frictionless electronic safety actuator 100, the electromagnet 110 is switched off to allow the magnetic plate 120 to shift horizontally back to its normal operating position. In some examples, the electromagnet 110 operates to generate a force to shift the magnetic plate 120 horizontally back to its original position, assisting the force provided by the at least one permanent magnet 122. Once the magnetic plate 120 has returned to its normal operating position, the electromagnet 110 can be switched off. In this example, minimal power is required to operate the frictionless electronic safety actuator 100, which improves the operating efficiency of the system.

[0056] Figure 4 、 5 6 show a second example of a frictionless electronic safety actuator 200. The frictionless electronic safety actuator 200 includes a first magnetic plate 210, a second magnetic plate 220, a stopper 212, and a spring 230 located within a housing 250. A connection arrangement 290 connects the second magnetic plate 220 to the connecting rod 80, which is configured to actuate the safety brake 24. The connection arrangement 290 can be any connection that allows the second magnetic plate 220 to move to actuate the connecting rod 80. In this example, the connection arrangement 290 is a pin.

[0057] In an example, the first magnetic plate 210 is an electromagnet. In another example, the stopper 212 is an electromagnet. In another example, both the first magnetic plate 210 and the stopper 212 are electromagnets. The electromagnet can take any suitable form, such as a straight core with a single coil or more than one coil. The electromagnets 210, 212 are positioned so as to act on the second magnetic plate 220 and move the second magnetic plate 220 from the position indicated by the figure. Figure 4 The rest position during normal operation as seen in Figure 6 The actuated position is shown as being displaced vertically upward from the rest position. The second magnetic plate 220 may be made of a ferrous material, may include one or more permanent magnets, or may be a permanent magnet.

[0058] Although in some examples the stopper 212 is an electromagnet, it can be any form of physical stopper. In some examples, the stopper 212 is a permanent magnet. In some examples, the stopper is resiliently mounted, preferably so that the resilient mounting can assist in resetting the magnetic plate. Figure 4 、 5 In the examples shown in Figures 2 and 6, the resilient mounting member is a spring 230, but other types of resilient mounting members may also be suitable, such as an actuator, a hydraulic ram, a pneumatic ram, etc.

[0059] exist Figure 4 、 5 In the example shown in Figures 1 and 2, the first magnetic plate 210 is located at the bottom of the housing 250, and during normal operation of the elevator, the second magnetic plate 220 rests above the first magnetic plate 210. The stopper 212 is attached to the top of the housing 250 via a spring 230.

[0060] When the frictionless electronic safety actuator 200 is activated, the electromagnet is operable to generate a force that moves the second magnetic plate 220 from the Figure 4Its rest position shown in FIG is moved upwards toward the stopper 212. Figure 5 As shown in FIG, this movement actuates the connecting rod 80, which pulls the safety brake 24. Figure 6 As shown in FIG, the movement is then absorbed by the compression of the spring 230. The stopper 212 limits the upward movement of the second magnetic plate 220.

[0061] The use of spring 230 allows the distance between first magnetic plate 210 and stopper 212 to be shortened, wherein when second magnetic plate 220 is pushed upward by the electromagnet of first magnetic plate 210, the space for the large actuation distance is absorbed by the compression of spring 230. Spring 230 can also absorb some of the force of the movement of second magnetic plate 220 to prevent damage to stopper 212 and second magnetic plate 220. It also assists in resetting. Although spring 230 is discussed with reference to this example, those skilled in the art will understand that various types of resilient mounting members may be suitable.

[0062] In this embodiment, when both the first magnetic plate 210 and the stopper 212 are electromagnets, the first magnetic plate 210 is operable to repel the magnetic plate 220, and the stopper 212 is operable to attract the magnetic plate 220, thereby improving the actuation efficiency of the safety brake 24. In this example, each electromagnet requires less power than a single electromagnet.

[0063] In the case where the first magnetic plate 210 is an electromagnet, the stopper 212 can be a permanent magnet configured to attract the second magnetic plate 220. When the safety brake 24 applies friction against the guide rail 20, the magnetic attraction between the second magnetic plate 220 and the stopper 212 can help prevent the second magnetic plate 220 from shifting downward under the pull from the safety brake 24.

[0064] In some examples, no power is required during normal operation because the second magnetic plate 220 is held in place by its own weight. Advantages of this include improved energy efficiency. In other examples, the natural magnetic force between the first magnetic plate 210 and the second magnetic plate 220 provides additional force to hold the second magnetic plate 220 in place even when the electromagnet of the first magnetic plate 210 is not powered.

[0065] In an example, the electromagnet of the first magnetic plate 210 is operable to generate a magnetic field to hold the second magnetic plate 220 in place during normal operation. This prevents any abnormal movement of the elevator car 16 from moving the second magnetic plate 220 in a manner that could accidentally trigger the safety brake 24.

[0066] exist Figure 4 、 5 In the example shown in FIG. 6 , in order to change the frictionless electronic safety actuator 200 from Figure 6 The trigger state is reset back to the state seen in Figure 4 In the middle position, the electromagnet operates to generate a reverse magnetic field to attract the second magnetic plate 220 back to its normal operating position. The force of the spring 230 can assist gravity to assist this movement.

[0067] The frictionless electronic safety actuator 100, 200 is fixed to the elevator car 16 and positioned relative to the safety brake 24 so that the linkage can actuate the safety brake 24. The frictionless electronic safety actuator 100, 200 is positioned so as not to be in direct contact with the elevator guide rails 20.

[0068] Those skilled in the art will appreciate that many forms of linkage mechanisms 80 between the frictionless electronic safety actuator 100, 200 and the safety brake 24 will be suitable for actuating the safety brake 24 based on the movement of the frictionless electronic safety actuator 100, 200. In addition, various types of safety brakes 24 are suitable for being actuated by the linkage 80 in this manner, such as safety brakes 24 that use wedges or rollers. In the example shown, the safety brake 24 is positioned below the frictionless electronic safety actuator 100, 200, however, it will be appreciated that other configurations are possible, for example, the frictionless electronic safety actuator 100, 200 may even be positioned to the side of or below the safety brake 24, for example, depending on the linkage used.

[0069] The example described above offers numerous advantages over conventional electronic safety actuators. The actuation of the safety brake is independent of the state of the guide rails or the speed of the elevator car. Furthermore, since actuation is independent of the friction between the electronic safety actuator and the guide rails 20, the response time to braking is improved. Since the actuation of the safety brake is completely independent of any interaction between the elevator car 16 and the guide rails 20, movement of the car will not affect the actuation of the safety brake. This improves the safety of the entire elevator system. A frictionless electronic safety actuator also offers the advantage of not damaging the guide rails.

[0070] Those skilled in the art will appreciate that the present disclosure has been illustrated by describing one or more particular aspects thereof, but that the present disclosure is not limited to these aspects; many variations and modifications are possible within the scope of the appended claims.

Claims

1. A frictionless electronic safety actuator (100, 200) for use in an elevator system, comprising: at least one electromagnet (110; 210, 212) and a magnetic plate (120; 220) attached to the connection arrangement (190; 290); wherein the connection arrangement (190; 290) is configured to connect the magnetic plate (120; 220) to an actuatable link (80) so as to move the safety brake (24) into frictional engagement with the elevator guide rail (20); wherein the at least one electromagnet (110; 210, 212) is operable to selectively generate a magnetic force acting on the magnetic plate (120; 220) to displace the magnetic plate (120; 220) and thereby move the connection arrangement (190; 290) to actuate the connecting rod (80) without the magnetic plate (120; 220) frictionally engaging the elevator guide rail (20); wherein the connection arrangement (190) comprises a compression spring arrangement (130) configured to convert a horizontal displacement of the magnetic plate (120) into a vertical movement of the connecting rod (80); and wherein the compression spring arrangement (130) generates a spring bias to return to a relaxed state that actuates vertical movement of the link (80) to move the safety brake (24) into frictional engagement with the elevator guide rail (20).

2. The frictionless electronic safety actuator (100) according to claim 1, wherein The connection arrangement (190) includes a plurality of leaf springs connected in series to form an accordion-like member (135) in a vertical direction, wherein one end is fixed and one end is movable in the vertical direction; and a link connection point (195) located on the movable end of the accordion-like member (135).

3. The frictionless electronic safety actuator (100) according to claim 2, wherein: Vertical movement of the plurality of leaf springs is guided so that a first side of the plurality of leaf springs is fixed in a horizontal direction and guided in the vertical direction, and a second side of the plurality of leaf springs is guided in the vertical direction and movable in the horizontal direction; and The second sides of the plurality of leaf springs are attached to the magnetic plate (120), and the horizontal movement is determined by the operation of the at least one electromagnet (110).

4. The frictionless electronic safety actuator (100) according to any one of claims 1 to 3, wherein: The magnetic plate (120) includes at least one permanent magnet (122).

5. The frictionless electronic safety actuator (100) according to claim 4, wherein The at least one electromagnet (110) is operable to generate a magnetic field to repel the magnetic plate (120).

6. The frictionless electronic safety actuator (100) according to any one of claims 1 to 3, wherein: The at least one electromagnet (110) is operable to generate a magnetic field to reposition the magnetic plate (120); wherein the magnetic plate (120) moves in the horizontal direction against the bias of the compression spring arrangement (130).

7. The frictionless electronic safety actuator (200) according to claim 1, wherein The at least one electromagnet (210, 212) is configured to move the magnetic plate (220) and the connection arrangement (290) in a vertical direction to directly displace the connecting rod (80) in the vertical direction.

8. The frictionless electronic safety actuator (200) according to claim 7, wherein A single electromagnet (210, 212) is configured to move the magnetic plate (220) in a vertical direction to vertically displace the connecting rod (80).

9. The frictionless electronic safety actuator (200) according to claim 7, wherein: The paired electromagnets (210, 212) are positioned to be vertically displaced so that a magnetic force is selectively generated to vertically displace the magnetic plate (220) between the two electromagnets (210, 212) so as to actuate the connecting rod (80).

10. The frictionless electronic safety actuator (200) according to any one of claims 7 to 9, wherein: The magnetic plate (220) is displaced toward a stopper (212), wherein the stopper (212) is elastically mounted.

11. The frictionless electronic safety actuator (200) according to claim 10, wherein: The resilient mounting of the stop (212) is arranged to relax to assist in resetting the magnetic plate (220).

12. The frictionless electronic safety actuator (200) according to any one of claims 7 to 11, wherein: The at least one electromagnet (210, 212) is operable to generate a magnetic field to displace the magnetic plate (220) upward in the vertical direction.

13. The frictionless electronic safety actuator (100, 200) according to any one of claims 1 to 3, wherein: The at least one electromagnet (110; 210, 212) is operable to remove or reverse the magnetic field in order to displace the magnetic plate (120; 220).

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