CN216546446U

CN216546446U - Wheel body assembly and movable equipment

Info

Publication number: CN216546446U
Application number: CN202121531154.5U
Authority: CN
Inventors: 许汉军; 宗振国
Original assignee: Weilan Continental Beijing Technology Co ltd
Current assignee: Weilan Continental Beijing Technology Co ltd
Priority date: 2021-07-06
Filing date: 2021-07-06
Publication date: 2022-05-17
Anticipated expiration: 2031-07-06

Abstract

The wheel body assembly and the movable equipment provided by the embodiment of the utility model are provided, wherein the wheel body assembly is applied to the movable equipment, the movable equipment comprises a machine body, and the wheel body assembly comprises: one end of the wheel shaft is connected with the wheel body, and the other end of the wheel shaft is inserted into the machine body; and the wheel shaft can move relative to the machine body; the detection device comprises a sensing piece and a triggering piece, wherein the sensing piece is used for being fixed on the machine body, the triggering piece is arranged on the wheel shaft in a surrounding mode along the circumferential direction of the wheel shaft, when the machine body is lifted, the wheel shaft moves relative to the machine body, and the relative distance between the sensing piece and the triggering piece in the moving direction of the wheel shaft changes. According to the wheel body assembly and the movable equipment provided by the technical scheme, once the movable equipment is lifted or falls, the detection device can detect in time, and then the movable equipment can be controlled to execute related actions, so that the use safety of the movable equipment is improved.

Description

Wheel body assembly and movable equipment

Technical Field

The utility model relates to the technical field of electric tool structure design, in particular to a wheel body assembly and movable equipment.

Background

The movable equipment, such as a mower, realizes the moving walking of the mower through wheels at the bottom. However, in the related art, once the mower falls or is manually lifted, the whole device cannot detect in time, but the bottom of the mower is provided with a cutter head to cut grass, and when the mower falls or is manually lifted, the cutter head at the bottom of the mower is easy to accidentally injure people, so that how to detect the falling or the manual lifting of the mower is particularly important.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention is directed to a wheel assembly and a mobile device that solve, or at least partially solve, the above problems.

The embodiment of the utility model provides a wheel body assembly, which is applied to movable equipment, wherein the movable equipment comprises a mounting seat, and the wheel body assembly comprises: one end of the wheel shaft is connected with the wheel body, and the other end of the wheel shaft is inserted into the machine body; and the wheel shaft can move relative to the machine body;

the detection device comprises a sensing piece and a triggering piece, wherein the sensing piece is used for being fixed on the machine body, the triggering piece is arranged on the wheel shaft in a surrounding mode along the circumferential direction of the wheel shaft, when the machine body is lifted, the wheel shaft moves relative to the machine body, and the relative distance between the sensing piece and the triggering piece in the moving direction of the wheel shaft changes.

In some embodiments, the trigger is uniformly circumferentially disposed on the axle along a circumference of the axle.

In some embodiments, the axle is rotatably coupled relative to the body, and the trigger is capable of following the axle for rotation.

In some embodiments, the vehicle body further comprises an upper limiting piece, the upper limiting piece is arranged on the wheel shaft and used for abutting against the machine body so as to limit the limit descending position of the wheel shaft;

and/or the lower limiting piece is arranged on the wheel shaft and is used for abutting against the machine body so as to limit the limit ascending position of the wheel shaft.

In some embodiments, an upper restraint is included that is removably coupled to the axle.

In some embodiments, the trigger member is located above the sensing member, and the trigger member moves toward the sensing member during the descending of the wheel axle;

or the triggering piece is positioned below the sensing piece, and the triggering piece moves towards the direction far away from the sensing piece in the descending process of the wheel shaft.

In some embodiments, the trigger is removably coupled to the axle;

and/or the trigger part is annular.

In some embodiments, at least two pins are inserted into the wheel shaft in the radial direction, the at least two pins have a spacing in the axial direction of the wheel shaft, and the trigger is limited in the spacing.

In some embodiments, the detection device comprises a hall sensor, the trigger comprises a magnet, and the sensor comprises a hall element.

In some embodiments, the wheel axle includes a vertical portion inserted into the machine body and a horizontal portion for mounting the wheel body, and the rotation axis of the wheel body coincides with the axis of the horizontal portion.

In some embodiments, the vehicle further comprises a mounting base connected to the body, the axle being mounted to the body by the mounting base.

In some embodiments, the mount is removably coupled to the body.

According to a second aspect of the embodiments of the present invention, there is provided a mobile device, including a body, and a wheel assembly as described in any one of the above.

In some embodiments, the bottom of the body has a recess facing the recess, and the mounting seat is detachably mounted to the recess.

In some embodiments, further comprising:

the driving device is connected with the executing device of the movable equipment and is used for driving the executing device to operate;

and the control device is electrically connected with the driving device and the detection device and is used for controlling the driving device to execute relevant actions when the detection device detects that the wheel axle descends.

According to the wheel body assembly and the movable equipment provided by the embodiment of the utility model, the wheel shaft capable of moving relative to the machine body is arranged on the mounting seat, and the detection device is arranged on the wheel shaft and the machine body, so that the movement action of the wheel shaft relative to the machine body can be detected, and therefore, when the movable equipment is lifted or falls, the movable equipment can be detected in time, and the use safety and the rationality of the movable equipment are improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of a wheel assembly according to an embodiment of the present invention;

FIG. 2 is a schematic view of a lawn mower with a wheel assembly according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of the wheel assembly mounted to a mower in accordance with an embodiment of the present invention;

fig. 4 is an electrical control schematic diagram of a lawn mower with a wheel assembly according to an embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the utility model, and not restrictive of the full scope of the utility model. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, and a person skilled in the art can solve the technical problem within a certain error range to substantially achieve the technical effect.

Furthermore, the term "coupled" is intended to include any direct or indirect coupling. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices. The following description is of the preferred embodiment of the utility model for the purpose of illustrating the general principles of the utility model and is not intended to limit the scope of the utility model. The scope of the present invention is defined by the appended claims.

It should be understood that the term "and/or" as used herein is merely a relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B, may represent: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The inventor has found through creative work that, for a movable device, usually, a wheel assembly at the bottom thereof is supported on a walking surface, and moves and walks, generally, an axle of the wheel assembly is fixedly mounted on a machine body of the movable device, and the whole wheel assembly cannot move relative to the machine body. Therefore, when the whole machine falls or is lifted, the machine cannot sense the falling or lifting condition in time, and therefore, if the whole machine is still in a working state, the user is easily injured by the execution device. For example, when a mower falls during operation, a user needs to pick up the mower again to return the mower to a normal operating area, and the mower is not stopped, so that the mower is still in operation, and in such a state, the user approaches the mower, and the mower is easily damaged by mistake.

In order to solve the above specific technical problems, the present invention provides the following embodiments to accurately detect whether the mobile device falls or is lifted, so that the mobile device can be controlled to generate corresponding actions to deal with the situation that the mobile device falls or is lifted. Thereby improving the safety and rationality of use of the mobile device.

FIG. 1 is a schematic structural view of a wheel assembly according to an embodiment of the present invention; FIG. 2 is a schematic view of a lawn mower with a wheel assembly according to an embodiment of the present invention; FIG. 3 is a cross-sectional view of the wheel assembly mounted to a mower in accordance with an embodiment of the present invention; fig. 4 is an electrical control schematic diagram of a lawn mower with a wheel assembly according to an embodiment of the present invention.

Referring to fig. 1 to 4, a wheel assembly according to an embodiment of the present invention is applied to a mobile device, the mobile device includes a body 100, and the wheel assembly 200 includes: the wheel axle 10, the wheel body 20 and the detection device 30.

One end of the wheel shaft 10 is connected with a wheel body 20, and the other end of the wheel shaft 10 is inserted into the machine body 100; and the wheel axle 10 can move relative to the machine body 100.

It should be noted that in one embodiment, the wheel 20 is supported on the ground or other medium, and the axle 10 can move up and down relative to the body 100 when the body 100 is lifted or dropped.

Specifically, the machine body 100 may be a main housing of the mobile device, and the wheel assembly 200 may be disposed below the machine body 100 to support the whole machine body 100. Generally, for a mobile device, since the body 100 has a certain volume, at least two wheel assemblies 200 may be disposed below the body 100 to stably support the body 100.

In this embodiment, as shown in fig. 1, the wheel axle 10 may be a special-shaped wheel axle, the wheel axle 10 may include at least a vertical portion 11 and a horizontal portion 12, the vertical portion 11 may be inserted into the machine body 100, the horizontal portion 12 may be used to mount the wheel body 20, and the rotation axis of the wheel body 20 coincides with the axis of the horizontal portion 12. Therefore, the wheel body 20 can be supported on the walking surface, and the movable equipment can walk smoothly.

The detecting device 30 includes a sensing member 31 and a triggering member 32, the sensing member 31 is used to be fixed to the machine body 100, and the triggering member 32 is disposed on the wheel axle 10 along the circumferential direction of the wheel axle 10. The trigger 32 may include a plurality of, or when the trigger 32 is a plurality of, a plurality of triggers 32 may be arranged at intervals in the circumferential direction of the axle 10. When there is only one trigger 32, the trigger 32 itself may be a ring structure, and the entire ring-shaped trigger 32 may be sleeved outside the axle 10. The triggering element 32 is mounted on the wheel axle 10, the wheel axle 10 can move relative to the machine body 100, the triggering element 32 can move along with the wheel axle 10, the sensing element 31 is fixed on the machine body 100, when the machine body 100 is lifted, the wheel axle 10 moves relative to the machine body 100, the distance between the triggering element 32 and the sensing element 31 changes due to the movement of the wheel axle 10, and the magnitude of the sensing signal between the triggering element 32 and the sensing element 31 changes due to the change of the distance between the triggering element 32 and the sensing element 31. The up and down movement of the wheel axle 10 can be sensed according to the change of the magnitude of the sensing signal. Therefore, the movement of the axle 10 is sensed by the triggering part 32 on the axle 10 and the sensing part 31 of the machine body 100, so that the movable equipment can be detected in time when being lifted or falling, thereby improving the use safety and rationality of the movable equipment.

In a specific application scenario, when the mobile device normally works in a working area, a ground surface or other walking surface supports the wheel body 20 and the wheel shaft 10, the triggering member 32 on the wheel shaft 10 may be at a first height, and when the mobile device suddenly falls or is suddenly lifted, the wheel shaft 10 and the wheel body 20 may naturally descend under the action of gravity, and the triggering member 32 on the wheel shaft 10 also descends to approach the sensing member 31 in the height direction, so that the sensing member 31 senses the height change of the triggering member 32 and the wheel shaft 10. Thereby knowing that the entire mobile device has fallen or been lifted.

In a preferred embodiment, the detection means 30 comprise a hall sensor, the trigger 32 comprises a magnet and the sensing member 31 comprises a hall element. The magnet is fixed on the wheel axle 10 and can move up and down along with the wheel axle 10, and the Hall element senses the magnetic field change of the magnet, so that the wheel axle 10 is determined to move up or down.

The embodiment of the present invention is not particularly limited with respect to the specific location of the trigger 32 on the axle 10. As shown in fig. 3, in an exemplary embodiment, the triggering member 32 may be located above the sensing member 31, when the mobile device is lifted or dropped, the axle 10 is lowered, and during the lowering of the axle 10, the triggering member 32 moves toward the sensing member 31, and the distance between the triggering member 32 and the sensing member 31 decreases. When the detecting means 30 is a hall sensor, the magnet provided on the wheel axle 10 is lowered, and the hall element senses an increase in magnetic field strength, thereby determining that the wheel axle 10 is lowered. When the movable equipment returns to the normal working area again and the wheel body 20 is supported on the walking surface, the wheel axle 10 rises, and during the rising process of the wheel axle 10, the triggering piece 32 moves towards the direction away from the sensing piece 31, and the distance between the triggering piece 32 and the sensing piece 31 becomes larger. When the detecting device 30 is a hall sensor, the magnet provided on the wheel axle 10 rises, the distance from the hall element increases, and the hall element senses the decrease in the magnetic field strength, thereby determining that the wheel axle 10 rises.

In other alternative embodiments, the triggering member 32 is located below the sensing member 31, the axle 10 descends when the mobile device is lifted or dropped, and the distance between the triggering member 32 and the sensing member 31 increases when the triggering member 32 moves away from the sensing member 31 during the descending of the axle 10. When the detecting device 30 is a hall sensor, the magnet provided on the wheel axle 10 is lowered, the distance between the magnet and the hall element is increased, and the hall element senses the decrease of the magnetic field strength, thereby determining that the wheel axle 10 is lowered. When the movable equipment returns to the normal working area again and the wheel body 20 is supported on the walking surface, the wheel axle 10 rises, the triggering piece 32 moves towards the direction close to the sensing piece 31 during the rising process of the wheel axle 10, and the distance between the triggering piece 32 and the sensing piece 31 becomes smaller. When the detecting device 30 is a hall sensor, the magnet provided on the wheel axle 10 rises, the distance from the hall element decreases, and the hall element senses the increase of the magnetic field strength, thereby determining that the wheel axle 10 rises.

It should be noted that the specific structures of the triggering element 32 and the sensing element 31 in this embodiment are only examples, and those skilled in the art may also select other sensors capable of detecting the distance or the position, such as a laser sensor, an infrared sensor, etc., and the present invention is not limited thereto, as long as the descending of the axle 10 can be detected.

As shown in fig. 4, further, in order to realize that the mobile device can perform corresponding actions after falling or being lifted. In some embodiments, a corresponding control device 40 may be provided in the movable apparatus, the control device 40 may be electrically connected to the detection device 30, and the control device 40 may also be electrically connected to a driving device 50 in the movable apparatus, the driving device 50 being connected to an actuating device 60 of the movable apparatus for driving the actuating device 60 to perform a corresponding action. In this embodiment, when the detecting device 30 detects that the wheel axle 10 descends, the control device 40 can control the driving device 50 to drive the executing device 60 to execute the relevant action, so as to control the mobile device to stop operating or change the operating state. For example, the cutter head of the mower is controlled to stop rotating, or the rolling brush of the sweeping robot is controlled to stop rotating.

According to the wheel body assembly provided by the embodiment of the utility model, the wheel shaft capable of ascending and descending is arranged on the machine body, and the detection device is arranged on the wheel shaft and the machine body, so that the movement action of the wheel shaft relative to the machine body can be detected, when the movable equipment is lifted or falls, the movable equipment can be detected in time, and the use safety and the reasonability of the movable equipment are improved.

In some embodiments, the trigger 32 may be detachably connected to the axle 10, and specifically, as shown in fig. 1, at least two pins X may be radially inserted into the axle 10, and at least two pins X have a distance in the axial direction of the axle 10, and the trigger 32 is limited in the distance. The trigger 32 is axially limited through the two pins X, so that the trigger 32 is fixed on the wheel shaft 10 in the axial direction, the structure is simple, the assembly and the assembly are convenient, and the trigger 32 is detachably fixed on the wheel shaft 10 and can be conveniently assembled and replaced.

Of course, in other embodiments, the trigger 32 may be non-removably attached to the axle 10, such as an interference fit, or the trigger 32 may be glued to the outside of the axle 10.

Further, the axle 10 may be rotatably coupled with respect to the body 100, and the trigger 32 may be capable of following the rotation of the axle 10. Specifically, the vertical portion 11 of the axle 10 may be rotatably connected with the machine body 100, and the horizontal portion 12 of the axle 10 may be rotatably connected with the wheel body 20, and the wheel body 20 may be rotatable with respect to the axle 10. In this way, the wheel body 20 itself is formed as a universal wheel, and the wheel body 20 can rotate about the horizontal portion 12 and can rotate about the axis of the vertical portion 11. Through the arrangement, the wheel body 20 can rotate flexibly, and the movable equipment can move straightly and turn conveniently.

Of course, more specifically, the triggering member 32 may be uniformly arranged on the wheel axle 10 around the wheel axle 10 along the circumference of the wheel axle 10, so that the relative position relationship between the triggering member 32 and the sensing member 31 only changes along the moving direction of the wheel axle 10 no matter how the triggering member 32 rotates relative to the machine body 100.

The trigger 32 in the embodiment of the present invention uniformly surrounds the axle 10 along the circumferential direction of the axle. Therefore, even if the wheel axle 10 rotates, a plurality of positions in the circumferential direction of the wheel axle 10 can be sensed by the sensing member 31, and the reliability of detection by the detecting device 30 is ensured.

It will be appreciated that the greater the number of triggers 32, the more closely spaced, and the more reliable the detection by the detection device 30. When the triggering member 32 is annular, any position in the circumferential direction of the wheel axle 10 can be sensed by the sensing member 31, so that no matter how the wheel axle 10 rotates and rotates at any rotating speed, the sensing member 31 can sense as long as the wheel axle 10 ascends and descends, and the reliability of detection by the detection device 30 is the best.

In some embodiments, the wheel assembly 200 provided by the embodiments of the present invention may further include a mounting seat 70, the mounting seat 70 may be connected to the machine body 100, and the wheel axle 10 may be mounted to the machine body 100 through the mounting seat 70. Preferably, the mounting base 70 can be detachably connected to the machine body 100, for example, the mounting base 70 can be detachably mounted to the machine body 100 by a fastener 80 such as a screw or a snap, and in the embodiment shown in fig. 1, the mounting base 70 can be mounted to the machine body 100 by three screws. A through hole through which the axle 10 passes may be provided in the mount 70, and the axle 10 may rotate in the through hole. When the wheel axle 10 is installed on the machine body 100 through the installation seat 70, the installation seat 70 can be directly fixed on the machine body 100 through a fastening piece, so that the installation of the wheel axle 10 is realized, the direct hole opening on the machine body 100 is avoided, the wheel axle 10 does not need to be installed in the whole machine, the installation is convenient, and the waterproof effect is good.

Of course, it is not excluded that, in some embodiments, the machine body 100 may be directly provided with a through hole for the axle 10 to pass through, and the axle 10 may be directly mounted on the machine body 100.

In some embodiments, in order to prevent the axle 10 from being separated from the machine body 100 during operation, as shown in fig. 1, the wheel assembly 200 may further include an upper limiting member 201, the upper limiting member 201 is disposed on the axle 10, and the upper limiting member 201 is configured to abut against the machine body 100 to limit the extreme descending position of the axle 10. The wheel assembly 200 may further include a lower stopper 202, the lower stopper 202 may be disposed on the axle 10, and the lower stopper 202 may be configured to abut against the machine body 100 to limit the extreme ascending position of the axle 10.

Specifically, the upper and

lower stoppers

201 and 202 may have a size larger than a through hole of the mounting base 70 through which the axle 10 passes, or larger than a through hole of the machine body 100 through which the axle 10 passes. This restricts the position of the wheel 10 that rises and falls.

When the movable equipment normally works in a working area, such as mowing grass on grass, the machine body 100 descends under the action of gravity due to the support of grass on the wheel shaft 10, the bottom of the machine body 100 abuts against the lower limiting piece 202 on the wheel shaft 10, the height of the wheel shaft 10 is high, and when the movable equipment falls or a user lifts the machine body 100, the wheel body 20 is separated from the grass, the wheel shaft 10 and the wheel shaft 10 descend under the action of gravity until the upper limiting piece 201 abuts against the machine body 100, so that the limit descending position of the wheel shaft 10 is limited, and the wheel shaft 10 is prevented from falling out of the machine body 100.

In some embodiments, at least the upper limiting member 201 can be detachably connected to the axle 10, and the user can insert the axle 10 into the mounting seat 70 or the machine body 100 and then install the upper limiting member 201 at a predetermined position, so as to facilitate the assembly of the wheel assembly 200. Of course, in other embodiments, the upper and

lower retainers

201, 202 may both be removably connected to the axle 10. The upper limiting piece 201 and the lower limiting piece 202 are detachably connected with the wheel shaft 10, so that the lower limiting piece 202 and the upper limiting piece 201 can be conveniently and independently replaced, and the maintenance cost is reduced.

Since the lower limiting member 202 is used to abut against the machine body 100 when the movable device is in a normal operating state, the lower limiting member 202 is in contact with the machine body 100 for a long time and has relative motion, and therefore, the lower limiting member 202 may preferably include an abrasion-resistant material, for example, an abrasion-resistant layer is provided on a surface of the lower limiting member 202 abutting against the machine body 100, or the lower limiting member 202 is made of an abrasion-resistant material as a whole, so as to prevent the lower limiting member 202 from being continuously abraded to affect the service life.

Alternatively, in some embodiments, the lower retainer 202 may be axially fixed with the axle 10, but circumferentially movable, such that the axle 10 does not rotate with the axle 10 during rotation, and therefore, the lower retainer 202 is relatively stationary with respect to the body 100 with a low probability of wear therebetween during normal operation of the movable apparatus, and therefore, in such a case, the lower retainer 202 may also not include wear-resistant material.

The second aspect of the embodiment of the present invention further provides a mobile device, which includes a body 100, and a wheel assembly 200 as provided in the foregoing embodiment.

In some embodiments, the bottom of the machine body 100 may have a recessed portion C recessed away from the direction of the wheel body 20, and the mounting seat 70 is detachably mounted on the recessed portion C. The machine body 100 is provided with the concave part C for the installation of the installation seat 70, so that the whole structure is compact, the size structure of the whole machine is smaller, and the miniaturization design of the whole machine is facilitated.

In some embodiments, further comprising: the driving device 50 is connected with the actuating device 60 of the movable equipment and is used for driving the actuating device 60 to operate; and the control device 40 is electrically connected with the driving device 50 and the detection device 30 and is used for controlling the driving device 50 to execute relevant actions when the detection device 30 detects that the wheel axle 10 is lifted.

It should be noted that the structure and function of the wheel body assembly 200 provided in this embodiment are the same as those of the wheel body assembly 200 provided in the foregoing embodiment, and specific reference may be made to the description of the foregoing embodiment, which is not repeated herein.

Various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A wheel body subassembly is applied to mobile device, mobile device includes the organism, its characterized in that, the wheel body subassembly includes:

one end of the wheel shaft is connected with the wheel body, the other end of the wheel shaft is inserted into the machine body, and the wheel shaft can move relative to the machine body;

2. The wheel body assembly of claim 1, wherein the trigger is disposed on the axle in a uniform surrounding manner along a circumferential direction of the axle;

and/or the wheel shaft is rotatably connected relative to the machine body, and the trigger piece can rotate along with the wheel shaft.

3. The wheel body assembly according to claim 1, further comprising an upper limiting member, wherein the upper limiting member is disposed on the wheel axle and is configured to abut against the machine body to limit a limit descending position of the wheel axle;

4. The wheel assembly of claim 3, including an upper retainer removably coupled to the axle.

5. The wheel assembly of claim 1, wherein the triggering member is located above the sensing member, and the triggering member moves toward the sensing member during the lowering of the axle;

6. The wheel assembly of claim 1, wherein the trigger is removably coupled to the axle;

and/or the trigger part is annular.

7. The wheel assembly of claim 6, wherein the axle has at least two pins radially inserted therein, the at least two pins having a spacing in an axial direction of the axle, and the trigger is retained in the spacing.

8. The wheel assembly of claim 1, wherein the sensing device comprises a hall sensor, the trigger comprises a magnet, and the sensor comprises a hall element.

9. The wheel assembly of claim 1, wherein the axle comprises a vertical portion inserted into the machine body and a horizontal portion for mounting the wheel, and the rotation axis of the wheel coincides with the axis of the horizontal portion.

10. The wheel assembly of claim 1, further comprising a mounting base, the mounting base being connected to the housing, the axle being mounted to the housing via the mounting base.

11. The wheel assembly of claim 10, wherein the mounting base is removably coupled to the body.

12. A mobile device comprising a body and a wheel assembly as claimed in any one of claims 1 to 11.

13. The movable apparatus according to claim 12, wherein the bottom of the body has a recess facing the recess, and the mount is detachably mounted to the recess.

14. The removable device of claim 12, further comprising: