Safety device for a stairlift and stairlift
The safety device for stairlifts uses centrifugal levers and pre-tensioned springs to ensure reliable activation and stop the stairlift when unsafe downward movements occur, addressing reliability and mechanical immobility issues.
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Utility models
- Current Assignee / Owner
- HEERS JOSEF
- Filing Date
- 2025-12-23
- Publication Date
- 2026-04-23
AI Technical Summary
Existing stairlift safety devices struggle with unreliable activation and potential mechanical immobility, leading to unsafe downward movements and the inability to switch states effectively.
A safety device with centrifugal levers and a catching mechanism, featuring pre-tensioned springs and cams, ensures robust and reliable activation by automatically transitioning to a wedge position when excessive speed is detected, preventing downward movement and engaging the rail to stop the stairlift.
The solution provides a robust, space-saving, and reliable safety device that reliably activates to prevent unsafe downward movements, ensuring the stairlift stops when necessary, with predefined actuation and rollover protection.
Smart Images
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Abstract
Description
[0001] The invention relates to a safety device for a stairlift with a stationary rail and a chassis, wherein the chassis of the stairlift is movable along a longitudinal axis of the rail in a deactivation state of the safety device by means of a safety roller of the safety device rolling on the rail of the stairlift, and wherein the chassis is prevented from a downward movement along the longitudinal axis of the rail in an activation state of the safety device by means of the safety device.
[0002] Stairlifts and safety devices for stairlifts are already known in the prior art. The stairlift is typically equipped with a stationary rail, a chassis, and a safety device. In a deactivated state, the chassis can move along a longitudinal axis of the rail by means of a safety roller rolling on the rail. In an activated state, the chassis is prevented from moving along the longitudinal axis of the rail by the safety device. The safety device serves to automatically stop the stairlift if it moves downwards at a speed exceeding the permissible limit.
[0003] The object of the present invention is to improve a safety device for a stairlift and a stairlift with a safety device.
[0004] To solve the problem, the catching device according to the invention, in conjunction with the preamble of claim 1, is characterized in that two centrifugal levers of the catching device are pivotally mounted on the catching roller parallel to an axis of rotation of the catching roller about a lever pivot axis by means of a pivot bearing, wherein a lever spring is tensioned between the respective centrifugal lever and the pivot bearing of the other centrifugal lever such that the respective centrifugal lever is biased against the centrifugal force, and wherein the catching device is designed such that, in the activation state of the catching device, at least one of the two centrifugal levers actuates a switching plate of the catching device by means of the centrifugal force acting on this centrifugal lever and against the aforementioned bias such that a catching claw of the catching device is moved from a rest position in which the catching claw on the switching plate is in the direction of a wedge position,The catch claw, which is clamped between the catch roller and the rail, is held pre-tensioned by a catch claw spring located between the catch claw and a bracket of the catch device, and can be automatically moved into the wedge position. During this transition, the catch claw is automatically moved from its rest position, corresponding to the deactivation state of the catch device, to its wedge position, corresponding to the activation state of the catch device, due to the spring action of the pre-tensioned catch claw spring. Since the respective lever spring is tensioned between the respective centrifugal lever and the pivot bearing of the other centrifugal lever in order to pre-tension the respective centrifugal lever against the centrifugal force, a defined, and therefore predetermined, position is achieved that is independent of the movement of the other centrifugal lever.Preloading of the respective lever spring is achievable. Furthermore, this problem is solved by a stairlift with the features of claim 10.
[0005] The particular advantage of the invention lies in the improved design of a safety device for a stairlift and a stairlift with a safety device. Due to the inventive design of the safety device and the stairlift, a robust and reliable safety device for a stairlift and a corresponding stairlift are provided. Furthermore, the safety device according to the invention can be designed to save space.
[0006] In principle, the safety device according to the invention can be freely selected within wide suitable limits with regard to type, function, material, and dimensions. Accordingly, the invention can be advantageously applied to very different stairlifts. By selecting a specific mass for the respective centrifugal lever, the centrifugal force-induced deflection of this lever can be preset. For example, to achieve an earlier deflection of the respective centrifugal lever, and thus an earlier transition of the safety device from its deactivation state to its activation state, the mass of the respective centrifugal lever can be increased as desired by appropriately selecting its material thickness. An increase in material thickness from 6 mm to 8 mm or 10 mm is purely an example.The advantage is that the other dimensions of the respective centrifugal lever can remain unchanged despite an increase in mass. The term "stairlift" is to be interpreted broadly here and encompasses any type of elevator, in particular inclined elevators, that has a carriage moving along a rail on its longitudinal axis. The invention is advantageously applicable not only in the domestic sector but also in commercial settings or public facilities.
[0007] An advantageous embodiment of the trapping device according to the invention provides that each of the two centrifugal levers has an external cam, wherein, in the activation state of the trapping device, at least one of the two centrifugal levers, by means of its external cam, actuates the switching plate, preferably a switching cam of the switching plate, by means of the centrifugal force acting on this centrifugal lever and against the aforementioned preload, such that the trapping claw can be automatically moved from its rest position to its wedge position. In this way, a defined, i.e., predetermined, and very powerful actuation of the switching plate by means of at least one of the two centrifugal levers is achieved. This applies in particular to the preferred embodiment of this embodiment.
[0008] A further advantageous embodiment of the catch device according to the invention provides that the two centrifugal levers are limited in their pivoting movement about the lever pivot axis of the respective pivot bearing by means of a stop of the catch device corresponding to the respective centrifugal lever, preferably that the respective stop is arranged to transmit force on the catch roller, and particularly preferably that the stop is designed as a pin joined to the catch roller. This limits the respective centrifugal lever in its pivoting movement about its lever pivot axis, so that the respective centrifugal lever cannot overturn in an undesired manner. If the respective centrifugal lever were to overturn, its function, namely the aforementioned centrifugal force-induced actuation of the switching plate, would no longer be performed if required.This rollover protection is particularly important for the so-called free-fall fall of the stairlift equipped with the safety device according to the invention. According to the preferred and especially the particularly preferred embodiment, the stop can be implemented in a very simple manner from a design and manufacturing perspective. For example, the pin can be pressed into a blind hole in the safety roller. Of course, embodiments of this further development are also conceivable in which the stop is designed as an integral part of the safety roller.
[0009] A particularly advantageous embodiment of the catching device according to the invention provides that each of the two centrifugal levers has an inner cam and the catching device has an impulse cam arranged on a catching roller axis of the catching roller in a torque-transmitting manner, wherein the catching device is designed such that in the deactivation state of the catching device both centrifugal levers with their inner cams rotate about the axis of rotation with the catching roller and can be actuated by the stationary impulse cam in an impulse-like manner and in the direction of the centrifugal force, preferably that the catching device is designed such that the catching claw can be automatically moved from its rest position to its wedge position when a predetermined rotational speed of the catching roller is exceeded.In this way, it is ensured in a very simple manner from a design, manufacturing, and operational perspective that the centrifugal levers in the deactivation state of the safety device according to the invention do not freeze in an undesirable way in their position corresponding to the deactivation state, i.e., do not become mechanically immobile over time to such an extent that, when necessary, the safety device cannot actually be switched from its deactivation state to its activation state. Instead, by means of this further development, the two centrifugal levers are forcibly moved repeatedly in the deactivation state of the safety device, namely with every movement of the chassis along the longitudinal axis of the rail, so that the aforementioned malfunction is effectively prevented.The preferred embodiment of this further development has the additional advantage that the aforementioned actuation of the switching plate by means of the impulse cam is not only supported, but is mainly carried out by means of the impulse cam.
[0010] Another advantageous embodiment of the trapping device according to the invention provides that the holder is designed for fastening the trapping claw spring and / or for fastening the switching plate, preferably that the switching plate is pivotably arranged on the holder about a switching plate pivot axis, wherein the switching plate is pivotable from a retaining position, in which the trapping claw pre-tensioned by means of the trapping claw spring is held on the switching plate by means of a retaining flag of the switching plate, into a release position, in which the trapping claw can be automatically moved from its rest position to its wedge position under the action of the trapping claw spring, particularly preferably that a pivoting force required for the aforementioned pivoting of the switching plate can be pre-adjusted by means of an adjusting device of the trapping device comprising at least one switching plate spring.This allows for a very simple design and manufacturing process for attaching the catch spring and / or the switching plate. The preferred embodiment of this development also offers advantages in actuating the switching plate when transitioning it from its retaining position, corresponding to the deactivation state of the catch device, to its release position, corresponding to the activation state of the catch device. For example, after this transition, the switching plate can be easily returned from its release position to its retaining position simply by pivoting it back around its pivot axis in the opposite direction. The particularly preferred embodiment of this development further has the advantage that the pivoting force required for the aforementioned transition can be preset to a predetermined value.For example, the at least one switching plate spring can be designed as at least one disc spring, which can be pre-tensioned in the desired manner by means of an adjusting screw of the aforementioned adjusting device.
[0011] An advantageous further development of the latter embodiment of the arresting device according to the invention provides that the arresting device is designed such that it can be at least partially attached to the chassis by means of the bracket. In this way, the attachment of the arresting claw spring and / or the attachment of the switching plate to the chassis can be implemented in a very simple manner from a design and manufacturing perspective.
[0012] Further advantages, features, and details of the invention can be found in the dependent claims and the following description. Features mentioned therein may be essential to the invention individually or in any combination. The drawings serve only as examples to clarify the invention and are not intended to be limiting.
[0013] They show: Fig. 1a an embodiment of the stairlift according to the invention with the safety device according to the invention in partial representation, in a partially cut-away side view, Fig. 1b the embodiment according to the Fig. 1a, in a top view, Fig. 2 a centrifugal lever of the exemplary embodiment in a top view (above) and a side view (below), Fig. 3 a spring holder of the exemplary embodiment for attaching a lever spring of one of the two centrifugal levers to the catch roller in a side view (top), a top view (middle) and as a preliminary product (bottom), Fig. 4 the catching claw of the exemplary embodiment in a detailed view perpendicular to the axis of rotation of the catching roller, Fig. 5 the switching plate of the embodiment in a side view (top) and in a top view (bottom), Fig. 6 an impulse plate of the exemplary embodiment with the impulse cam in a top view (above) and in a cut side view (below) and Fig. 7 the holder of the embodiment in a side view (top left), a front view (top right) and in a top view (bottom).
[0014] The Fig. Figures 1a to 7 show an embodiment of the stairlift according to the invention with the safety device according to the invention. Identical components are identified by the same reference numerals.
[0015] Stairlift 2 is in the Fig. 1a and Fig. 1b only partially shown. Fig. Figures 2 to 7 show only individual parts of the embodiment. The stairlift 2 has a fixed rail 4, a chassis 6 and a safety device 8, wherein the chassis 6 is mounted in a housing in the Fig. 1a and Fig. In the deactivation state of the safety device 8 shown in Figure 1b, the trolley 6 is movable along a longitudinal axis 12 of the rail 4 by means of a safety roller 14 of the safety device 8 rolling on the rail 4, and in an activation state of the safety device 8 (not shown), the trolley 6 is prevented from moving downwards along the longitudinal axis 12 of the rail 4 by means of the safety device 8. The trolley 6 of the stairlift 2 is movable along the longitudinal axis 12 of the rail 4 in the deactivation state of the safety device 8 by means of the safety roller 14 of the safety device 8 rolling on the rail 4 of the stairlift 2. The safety roller 14 is rotatably mounted on the trolley 6 of the stairlift 2 about a pivot axis 15.
[0016] According to the invention, the catching device 8 has two centrifugal levers 16, wherein the two centrifugal levers 16 are pivotally mounted on the catch roller 14 parallel to the axis of rotation 15 of the catch roller 14 by means of a pivot bearing 18 of the catching device 8 about a lever pivot axis. The lever pivot axis of the respective pivot bearing 18 runs in the Fig. 1a perpendicular to the plane of the image. Between the respective centrifugal lever 16, namely a spring retainer 17 of the respective centrifugal lever 16, and a retaining screw 19 of the other centrifugal lever 16, a lever spring 20 of the catch device 8 is tensioned such that the respective centrifugal lever 16 is biased against the centrifugal force, wherein the catch device 8 is designed such that, in the activation state of the catch device 8, at least one of the two centrifugal levers 16, by means of the centrifugal force acting on this centrifugal lever 16 and against the aforementioned bias, actuates a switching plate 22 of the catch device 8 such that a catch claw 24 of the catch device 8 is opened from one side into the Fig. 1a and Fig. 1b shown rest position, in which the catch claw 24 on the switching plate 22 in the direction of a wedge position not shown, in which the catch claw 24 is clamped between the catch roller 14 and the rail 4, is held pre-tensioned by means of a catch claw spring 26 of the catch device 8 arranged between the catch claw 24 and a holder 38 of the catch device 8, can be automatically transferred into the wedge position.
[0017] In the present embodiment, each of the two centrifugal levers 16 has an external cam 28, wherein, in the activation state of the catch device 8, at least one of the two centrifugal levers 16, by means of its external cam 28, actuates the switching plate 22, namely a switching cam 30 of the switching plate 22, by means of the centrifugal force acting on this centrifugal lever 16 and against the aforementioned preload, such that the catch claw 24 can be automatically moved from its rest position to its wedge position. Furthermore, the pivoting movement of the two centrifugal levers 16 about the lever pivot axis of the respective pivot bearing 18 is limited here by means of a stop 32 of the catch device 8 corresponding to the respective centrifugal lever 16, wherein the respective stop 32 is arranged on the catch roller 14 in a force-transmitting manner, namely such that the respective stop 32 is designed as a pin joined to the catch roller 14.
[0018] Furthermore, in the present embodiment, each of the two centrifugal levers 16 has an internal cam 34, and the catch device 8 has an impulse cam 36 arranged on a catch roller axle 48 of the catch roller 14 to transmit torque. The catch device 8 is designed such that, in the deactivation state of the catch device 8, both centrifugal levers 16 with their internal cams 34 rotate about the axis of rotation 15 with the catch roller 14 and can be actuated by the stationary impulse cam 36 in an impulse-like manner and in the direction of the centrifugal force. The catch device 8 is further designed such that, if a predetermined rotational speed of the catch roller 14 is exceeded, the catch claw 24 can be automatically moved from its rest position to its wedge position by means of the impulse cam 36. One of the two centrifugal levers 16 is in the Fig. 2 is shown in more detail in two separate illustrations.
[0019] The two centrifugal levers 16 are identical in design, so that the descriptions for one of the two centrifugal levers 16 also apply to the other. The same applies to the other identical parts, namely the two spring retainers 17 for holding the respective lever spring 20 on the corresponding centrifugal lever 16. One of the two spring retainers 17 is in the Fig. Figure 3 shows three separate illustrations. The impulse cam 36 is arranged to transmit torque to the catch roller axle 48 of the catch roller 14 by means of an impulse plate 37 and a socket head screw 100. See in particular the Fig. 6.
[0020] The bracket 38 is designed here for fastening the catch claw spring 26 and for fastening the switching plate 22, wherein the switching plate 22 is pivotably arranged on the bracket 38 about a switching plate pivot axis 40 by means of a switching plate rotary bearing 39, and wherein the switching plate 22 is guided by a Fig. 1a and Fig. The retaining position shown in Figure 1b, in which the catch claw 24, pre-tensioned by the catch claw spring 26, is held on the switching plate 22 by a retaining flag 23 of the switching plate 22, can be pivoted into a release position (not shown), in which the catch claw 24 can be automatically moved from its rest position to its wedge position under the action of the catch claw spring 26. In the present embodiment, the pivoting force required for the aforementioned pivoting of the switching plate 22 is adjustable in advance by means of an adjusting device 44 of the catch device 8, which has at least one switching plate spring 42.The at least one switching plate spring 42 is designed here as a stack of disc springs, wherein the stack of disc springs is positioned under preload between an end face of the switching plate pivot bearing 39 of the switching plate 22 on one side and a screw head of an adjusting screw 46 of the adjusting device 44 screwed into the switching plate pivot bearing 39 of the switching plate 22 on the other side. In the present embodiment of the invention, the catch device 8 is designed such that the catch device 8, namely the switching plate 22 and the catch claw spring 26, can be attached to the chassis 6 indirectly by means of the bracket 38 and directly, namely a portion of the catch device 8, by means of the catch roller axle 48 of the catch roller 14. The bracket 38 is attached to the chassis 6 by means of two screw connections.
[0021] The catch claw 24 is designed here as a disc rotatable about the axis of rotation 15 of the catch roller 14, wherein the disc has a mounting tab 50 for attaching the catch claw spring 26 and, essentially diametrically opposite this, a retaining stop 52 for holding the catch claw 24 on the switching plate 22, namely on the retaining flag 23 of the switching plate 22, in the rest position of the catch claw 24. The catch claw 24 further has a defined wedge section 54 for clamping the catch claw 24 between the catch roller 14 and the rail 4 in the wedge position of the catch claw 24, wherein the wedge section 54 extends from the retaining stop 52 over an angular range of 30° to 40°, namely 35°, and that the wedge section 54 has teeth that engage with the rail 4 in the wedge position of the catch claw 24. See in particular the Fig. 4.
[0022] The switching plate 22 of the present embodiment additionally has a shut-off flag 25 for automatically shutting off a drive of the stairlift 2 (not shown) in the release position of the switching plate 22 (not shown). See in particular the Fig. 5.
[0023] The following describes the functioning of the stairlift according to the invention with the safety device according to the present embodiment, based on the Fig. 1a to 7 briefly explained.
[0024] First, the catching device 8 is located, as can be seen from the Fig. 1a and Fig.As shown in Figure 1b, the stairlift 2 is in its deactivation state. The chassis 6 of the stairlift 2 can therefore be moved along the longitudinal axis 12 of the rail 4 of the stairlift 2. This is done in the usual way by means of the drive of the stairlift 2 (not shown). In the deactivation state of the safety device 8, the chassis 6 of the stairlift 2 moves along the longitudinal axis 12 of the rail 4 by means of the safety roller 14 of the safety device 8, which rolls on the rail 4 of the stairlift 2. The safety roller 14 rotates on the safety roller axle 48, which is fixedly screwed into the chassis 6. The impulse cam 36 is stationary. The safety roller 14 rotates around the impulse cam 36 with the two centrifugal levers 16, which are forcibly pushed outwards by the impulse cam 36 via the inner cams 34 with each revolution of the safety roller 14. The rotational speed of the safety roller 14 is below the speed specified below.The centrifugal levers 16 are therefore regularly pivoted around the lever pivot axes of the two pivot bearings 18 during normal operation of the stairlift 2; however, not in such a way that the centrifugal levers 16 with their outer cams 28 would actuate the switching cam 30 of the switching plate 22.
[0025] If a malfunction occurs, causing the chassis 6 to move downwards along the longitudinal axis 12 of the rail 4 in an uncontrolled and unsafe manner, faster than intended, the safety device 8 is automatically switched from its deactivated state to its activated state. In this process, at least one of the two centrifugal levers 16, by means of the centrifugal force acting on it and contrary to the aforementioned preload, actuates the switching cam 30 of the switching plate 22 with its outer cam 28, thus switching the switching plate 22 from its retaining position to its releasing position. During this process, the switching plate 22 is rotated about the switching plate pivot axis 40, and the retaining flag 23 of the switching plate 22 on one side and the holding stop 52 of the safety claw 24 on the other side are disengaged. The pivoting force required for this is preset by means of the adjusting device 44.During the aforementioned transition, the catch claw 24 is moved from its rest position, in which the catch claw 24 was held biased against the switching plate 22 towards its wedge position by means of the catch claw spring 26, to its wedge position (not shown), in which the catch claw 24 is clamped between the catch roller 14 and the rail 4, by means of the spring force of the catch claw spring 26. The actuation of the switching cam 30 by means of at least one of the two centrifugal levers 16 is supported at least by the aforementioned impulse cam 36 and its interaction with the inner cams 34, namely, for example, in such a way that the catch claw 24 can be automatically moved from its rest position to its wedge position when a predetermined rotational speed of the catch roller 14 is exceeded.Depending on the specific design of the safety device 8, the impulse cam 36 can either merely assist or primarily cause the aforementioned movement of the centrifugal levers 16 in the direction of centrifugal force. The stops 32 prevent the two centrifugal levers 16 from overturning in an undesired manner. In its wedge position, the safety claw 24 presses against the rail 4 with its wedge section 54. The teeth arranged in the wedge section 54 engage with the rail 4, thus providing a very effective stopping action. To prevent the drive of the stairlift 2 (not shown) from working undesirably against the clamping effect of the safety claw 24 between the catch roller 14 and the rail 4, the drive of the stairlift 2 is automatically switched off by the shut-off flag 25 of the switching plate 22 when the switching plate 22 moves from its restraint position to its release position.
[0026] However, the invention is not limited to the present embodiment. See in particular the relevant explanations in the introductory section of the description and the alternatives and options mentioned in the specific description section.
Claims
[1] Safety device (8) for a stairlift (2) with a stationary rail (4) and a chassis (6), wherein the chassis (6) of the stairlift (2) is movable along a longitudinal axis (12) of the rail (4) in a deactivation state of the safety device (8) by means of a safety roller (14) of the safety device (8) rolling on the rail (4) of the stairlift (2), and wherein the chassis (6) is prevented from a downward movement along the longitudinal axis (12) of the rail (4) in an activation state of the safety device (8) by means of the safety device (8), characterized by, that two centrifugal levers (16) of the catching device (8) are pivotally mounted on the catching roller (14) parallel to a pivot axis (15) of the catching roller (14) by means of a pivot bearing (18) of the catching device (8) so as to be pivotally movable about a lever pivot axis, wherein a lever spring (20) of the catching device (8) is tensioned between each centrifugal lever (16) and the pivot bearing (18) of the other centrifugal lever (16) such that the respective centrifugal lever (16) is biased against the centrifugal force, and wherein the catching device (8) is designed such that in the activation state of the catching device (8) at least one of the two centrifugal levers (16) actuates a switching plate (22) of the catching device (8) by means of the centrifugal force acting on this centrifugal lever (16) and against the aforementioned bias such that a catching claw (24) of the catching device (8) is moved from a rest position,in which the catch claw (24) on the switching plate (22) in the direction of a wedge position, in which the catch claw (24) is clamped between the catch roller (14) and the rail (4), is held pre-tensioned by means of a catch claw spring (26) of the catch device (8) arranged between the catch claw (24) and a holder (38) of the catch device (8), can be automatically moved into the wedge position. [2] Catching device (8) according to claim 1, characterized by , that each of the two centrifugal levers (16) has an external cam (28), wherein in the activation state of the catching device (8) at least one of the two centrifugal levers (16) with its external cam (28) actuates the switching plate (22), preferably a switching cam (30) of the switching plate (22), by means of the centrifugal force acting on this centrifugal lever (16) and against the aforementioned preload, such that the catching claw (24) can be automatically transferred from its rest position to its wedge position. [3] Catching device (8) according to claim 1 or 2, characterized by , that the two centrifugal levers (16) are limited in their pivoting movement about the lever pivot axis of the respective pivot bearing (18) by means of a stop (32) of the catch device (8) corresponding to the respective centrifugal lever (16), preferably that the respective stop (32) is arranged to transmit force on the catch roller (14), particularly preferably that the stop (32) is designed as a pin joined to the catch roller (14). [4] Catching device (8) according to any one of claims 1 to 3, characterized by, that each of the two centrifugal levers (16) has an internal cam (34) and the catching device (8) has an impulse cam (36) arranged on a catching roller axis (48) of the catching roller (14) in a torque-transmitting manner, wherein the catching device (8) is designed such that in the deactivation state of the catching device (8) both centrifugal levers (16) with their internal cams (34) rotate about the axis of rotation (15) with the catching roller (14) and can be actuated by the stationary impulse cam (36) in an impulse manner and in the direction of the centrifugal force, preferably that the catching device (8) is designed such that the catching claw (24) can be automatically moved from its rest position to its wedge position when a predetermined rotational speed of the catching roller (14) is exceeded. [5] Catching device (8) according to any one of claims 1 to 4, characterized bythat the holder (38) is designed for fastening the catch claw spring (26) and / or for fastening the switching plate (22), preferably that the switching plate (22) is pivotably arranged on the holder (38) about a switching plate pivot axis (40), wherein the switching plate (22) is pivotable from a retaining position, in which the catch claw (24) pre-tensioned by means of the catch claw spring (26) is held on the switching plate (22) by means of a retaining flag (23) of the switching plate (22), to a release position, in which the catch claw (24) is automatically movable from its rest position to its wedge position under the action of the catch claw spring (26), particularly preferably that a pivoting force required for the aforementioned pivoting of the switching plate (22) is pre-adjustable by means of an adjusting device (44) of the catching device (8) having at least one switching plate spring (42). [6] Catching device (8) according to claim 5, characterized by, that the arresting device (8) is designed such that the arresting device (8) can be attached at least partially to the chassis (6) by means of the bracket (38). [7] Catching device (8) according to any one of claims 1 to 6, characterized by , that the catch claw (24) is designed as a disc rotatable about the axis of rotation (15) of the catch roller (14), preferably that the disc has a fastening tab (50) for fastening the catch claw spring (26) and, substantially diametrically opposite this, a retaining stop (52) for holding the catch claw (24) on the switching plate (22) in the rest position of the catch claw (24). [8] Catching device (8) according to claim 7, characterized by, that the catching claw (24) has a defined wedge area (54) for clamping the catching claw (24) between the catching roller (14) and the rail (4) in the wedge position of the catching claw (24), preferably that the wedge area (54) extends from the holding stop (52) over an angle range of 30° to 40°, in particular 35° and / or that the wedge area (54) has teeth engaging with the rail (4) in the wedge position of the catching claw (24). [9] Catching device (8) according to any one of claims 5 to 8, characterized by , that the switching plate (22) has a shut-off flag (25) for automatically shutting off a drive of the stairlift (2) in the release position of the switching plate (22). [10] Stairlift (2) comprising a fixed rail (4), a chassis (6) and a safety device (8), wherein the chassis (6) in a deactivation state of the safety device (8) is movable along a longitudinal axis (12) of the rail (4) by means of a safety roller (14) of the safety device (8) rolling on the rail (4), and wherein the chassis (6) in an activation state of the safety device (8) is prevented from a downward movement along the longitudinal axis (12) of the rail (4) by means of the safety device (8), characterized by , that the catching device (8) is designed according to one of claims 1 to 9.