Braking device for electric motor and electric motor

Abstract

The utility model relates to a braking device used for a motor, the motor comprises a motor housing and a motor shaft extending out of the motor housing along the axial direction, the braking device is characterized in that the braking device comprises an annular base body and at least two braking elements capable of elastically deforming, the base body comprises a continuous outer surface, and the outer surface of the base body is provided with a plurality of braking elements capable of elastically deforming. The braking element protrudes inwards from the inner surface of the base body and makes contact with the motor shaft in an interference fit mode, and therefore sliding friction is formed between the motor shaft and the braking element in the rotating operation process of the motor shaft. In addition, the utility model also relates to a motor with the brake device.

Description

Technical Field

[0001] The utility model relates to a braking device for a motor and a motor including the braking device. Background Art

[0002] In the field of electric furniture, electric furniture can have various postures. For example, for an electric sofa, there are sitting postures, TV postures, and lying postures, and for an electric bed, there are lowering and lifting postures. The change processes of these postures are all completed by driving with a motor connected to a mechanical structure. However, during the posture change process, the load force on the motor is too large, resulting in the motor often not being able to brake immediately when it stops moving. This untimely braking will bring potential safety hazards, such as the user being pinched or bruised, and the uncontrolled accidental collision of the movable furniture itself with obstacles, such as walls.

[0003] To achieve safe operation, sometimes motors with a large self-locking force are used. However, in such motors, there are often problems such as too high cost of electric push rods and difficult processing. As an alternative, external resistance is also used to achieve braking. For example, an independent brake pad is installed outside the end cover of the motor housing where the motor shaft extends out as a stopping device. However, this design and assembly process is cumbersome and will bring additional working hours and manufacturing costs.

[0004] Therefore, the existing designs of motors on the current market often cannot meet the needs. Summary of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide a motor with a simple structure, a simple installation process, and safer operation.

[0006] To solve the above technical problem, the utility model provides a braking device for a motor, and the motor includes a motor housing and a motor shaft extending axially from the motor housing. According to the utility model, the braking device includes an annular base body and at least two elastically deformable braking elements, wherein the base body includes a continuous outer surface, and the braking elements protrude inward from the inner surface of the base body and contact the motor shaft in an interference fit manner, so as to form a sliding friction between the motor shaft and the braking elements during the rotational operation of the motor shaft.

[0007] Compared with the motor braking devices in the prior art, the base body of the braking device according to the present utility model as a whole includes a continuous outer surface. That is to say, at any point on the outer surface of the base body, when a tangent line is made, the part of the base body adjacent to the tangent point is located on the same side of the tangent line. In other words, the outer surface of the base body does not include recessed structures such as grooves, cuts, slits, etc. This design makes the base body of the braking device convex and smooth to a certain extent, thereby reducing the manufacturing difficulty and reducing the installation man-hours. The braking element of the braking device is always in interference fit with the motor shaft, so as to always apply an appropriate degree of braking force to the motor shaft. Therefore, when the motor stops running, the braking device can timely and effectively achieve the complete and thorough braking of the motor shaft. It should be noted here that the braking effect of the braking device on the motor shaft will not overly affect the normal rotation of the motor shaft. That is to say, the braking device will not lock the rotating motor shaft, but form a sliding friction between the two.

[0008] Preferably, the braking device is of an integral structure. Here, the braking device can be injection-molded at one time or in steps using an injection-molding material. A heat-resistant polymer material can be used here, and its hardness is preferably lower than that of the motor shaft.

[0009] According to a preferred embodiment of the present utility model, at least a part of the base body includes a cylindrical outer surface. Preferably, the outer surface of the base body can be completely cylindrically configured or partially configured as a cylinder, such as a cylinder with chamfers.

[0010] According to a preferred embodiment of the present utility model, the braking elements are uniformly arranged along the circumferential direction of the inner surface of the base body at the same angular distance. Thereby, the braking force is uniformly applied to the motor shaft, so as to achieve stable motor operation and avoid excessive noise and unnecessary tremors during operation. Preferably, the braking device includes three braking elements. In this case, the three braking elements are uniformly distributed at an angular distance of 120°.

[0011] According to a preferred embodiment of the present utility model, the braking element includes a protruding arm extending inward from the inner surface of the base body and a braking arm connected to the protruding arm, wherein the braking arm is configured to be in frictional contact with the motor shaft. Here, the "extending inward from the inner surface of the base body" is in reference to the geometric center of the annular base body. In this case, one end of the braking arm connected to the protruding arm points to the center of the circle, that is to say, points inward.

[0012] According to a preferred embodiment of the present utility model, the braking arm is configured to be arcuately concave. Herein, the "concave" is with reference to the side of the braking arm facing the motor shaft. The extending trend of the concave braking arm generally matches the circumferential surface of the motor shaft, so as to establish the largest possible braking surface between the braking arm and the motor shaft, and thus provide a greater braking force with limited spatial dimensions.

[0013] According to a preferred embodiment of the present utility model, the braking elements respectively include two protruding arms and a braking arm connecting the two protruding arms. Preferably, in this embodiment, when observing from the outside to the inside along the radial direction of the braking device, the distance between the two protruding arms of the braking element gradually increases. In this case, each braking element is respectively configured in a C shape by its two protruding arms and a braking arm, wherein the braking element as a whole gradually expands from its bottom end to its top end. When the top end of the braking element, that is, the braking arm, interacts with the motor shaft, the braking element is more likely to deform, thereby increasing the frictional braking force on the motor shaft and improving the braking effect.

[0014] According to an alternative embodiment of the present utility model, the braking elements respectively only include one protruding arm and a braking arm connected to the protruding arm. In this case, each braking element is respectively configured in a T shape by its one protruding arm and a braking arm, wherein the braking element as a whole suddenly expands from its bottom end to its top end. Similarly, when the top end of the braking element, that is, the braking arm, interacts with the motor shaft, the braking element is more likely to deform, thereby increasing the frictional braking force on the motor shaft and improving the braking effect. Preferably, in this embodiment, the protruding arm extends obliquely with respect to the radial direction of the braking device.

[0015] According to an alternative embodiment of the present utility model, when observing in the axial direction of the braking device, the braking elements extend within the base body. That is to say, the dimension of the braking element in the axial direction does not exceed the dimension of the base body in the axial direction.

[0016] According to a preferred embodiment of the present utility model, the braking device further includes at least one holding portion arranged on the base body, and the braking device is fixedly installed relative to the motor housing by using this holding portion. Preferably, two holding portions are arranged on the base body. More preferably, the two holding portions are arranged opposite to each other. Thereby, the braking device is symmetrically configured as a whole, reducing the processing difficulty and simplifying the assembly process.

[0017] To solve the above technical problem, the present utility model further provides a motor, which includes a motor housing, a motor shaft and the above-mentioned braking device. Description of the Drawings

[0018] The embodiments of the present utility model will be described in detail below with the aid of the drawings.

[0019] Figure 1 Schematic side view showing a motor according to the present utility model;

[0020] Figure 2 Schematically showing Figure 1 Perspective view of the shown motor;

[0021] Figure 3 Schematic perspective view showing a braking device for a motor according to a first embodiment of the present utility model;

[0022] Figure 4 Schematically showing Figure 3 Front view of the shown braking device;

[0023] Figure 5 Schematically showing Figure 3 Side view of the shown braking device;

[0024] Figure 6 Schematic perspective view showing a braking device for a motor according to a second embodiment of the present utility model;

[0025] Figure 7 Schematically showing Figure 6 Front view of the shown braking device;

[0026] Figure 8 Schematically showing Figure 6 Side view of the shown braking device;

[0027] Figure 9 Schematic partial cross-sectional view showing a mounting manner of the braking device according to the present utility model on the motor; and

[0028] Figure 10 Schematic view showing the connection manner of the braking device and the motor end plate according to the present utility model. Detailed implementation manners

[0029] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0030] As used herein, "one embodiment" or "an embodiment" refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present utility model. In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. Moreover, the terms "first", "second", etc. are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present utility model described herein can be implemented in an order other than those illustrated or described herein.

[0031] Figure 1 and Figure 2 respectively schematically show a motor 1 according to the present utility model, which includes a motor housing 10 with a front end cover 12 and a rear end cover 14, a motor shaft 20 protruding outward from the front end cover 12, a front bearing 40 supporting the motor shaft 20 at the front of the motor, and a braking device 30.

[0032] The motor 1 can be configured as a brushed DC motor, for example, and it also includes magnetic tiles, iron cores, commutators, brush holders, etc. that are not specifically labeled. Since its basic working principle is known, it will not be elaborated here.

[0033] According to the present utility model, the braking device 30 is sleeved on the motor shaft 20 from the front of the motor housing 10, wherein the braking device abuts against the end face of the front bearing 40 and is fixedly installed relative to the motor housing 10.

[0034] The braking device 30 includes an annular base body 31 and at least two braking elements 32. As Figures 3 to 10 shown, the braking device 30 preferably includes three braking elements 32.

[0035] The base body 31 of the braking device 30 is integrally constructed as an annular shape especially as Figure 4 and Figure 7 shown, wherein the outer surface of the base body 31 is continuous, that is, no recessed shapes such as grooves, cuts, slits, etc. are formed on the outer surface of the base body, but it extends in a substantially continuous arc. In addition, at least a part of the outer surface of the base body 31 is constructed as a cylindrical shape, wherein especially asFigure 3 , Figure 5 , Figure 6 and Figure 8 As shown in Figure 8 , the outer surface of the base body 31 includes a cylindrical circumferential surface 310 centered along the axial direction x, and a first transition surface 311 and a second transition surface 312 that are respectively located on both sides of the cylindrical circumferential surface 310 and are inclined and chamfered.

[0036] The braking element 32 protrudes inward from the inner surface of the base body 31, that is, in the direction of the geometric center O of the base body 31. The braking element 32 is preferably integrally formed with the base body 31. Among them, the braking element 32 can be integrally manufactured with the base body 31 by methods such as injection molding process and casting process, or can be fixedly connected to the base body 31 in a non-detachable manner by bonding, welding, etc. Especially as Figure 5 and Figure 8 shown, the braking element 32 extends within the dimension range of the base body 31 in the axial direction x and does not protrude outward from the base body 31 in the axial direction x.

[0037] In this embodiment, the three braking elements 32 are evenly distributed on the inner surface of the base body 31 at the same angular distance of 120°, so that a uniform braking force can be applied to the motor shaft 20.

[0038] As Figures 3 to 5 shown, each braking element 32 may include two protruding arms 321 extending inward from the inner surface of the base body 31 and a braking arm 322 connecting the two protruding arms 321, so that a C-shaped braking part is formed by the two protruding arms 321 and the braking arm 322.

[0039] When the braking device 30 is installed on the electric motor 1, the braking device 30 is sleeved on the motor shaft 20. Among them, the braking element 32 is in interference fit contact with the motor shaft 20, and among them, the three braking arms 322 surround the circumferential surface of the motor shaft 20 circumferentially, so as to form a sliding friction between the motor shaft 20 and the braking arms 322 during the rotational operation of the motor shaft 20. In order to provide a greater braking force with limited dimensions, when observed from the side of the braking arm 322 facing the motor shaft 20, the braking arm 322 is configured to be concave in an arc shape. Preferably in this case, the arc extension direction of the braking arm 322 generally matches the circumferential surface of the motor shaft 20, so that the braking arm 322 contacts the motor shaft 20 with as large a contact surface as possible, and a braking surface as large as possible is established between the two to improve the braking force. In addition, when observed along the direction from the inner surface of the base body 31 to the geometric center O of the base body 31, that is, along the radial direction R from the outside to the inside, the distance between the two protruding arms 321 of each braking element 31 gradually increases, so that the width of the C-shaped braking part gradually increases as a whole. This shape makes the C-shaped braking part prone to elastic deformation when subjected to an external force. The braking arm 322 deforms as the motor shaft 20 rotates, driving the protruding arm 321 to tilt accordingly, improving the braking effect.

[0040] As Figures 6 to 8 shown, the braking element 32 may include only one protruding arm 321 extending inward from the inner surface of the base body 31 and a braking arm 322 connected to the protruding arm 321, so as to form a T-shaped braking part by the protruding arm 321 and the braking arm 322. This T-shaped shape makes the braking part prone to elastic deformation when subjected to an external force. The braking arm 322 deforms as the motor shaft 20 rotates, driving the protruding arm 321 to tilt accordingly, improving the braking effect.

[0041] Similarly, when the braking device 30 is installed on the electric motor 1, the braking element 32 is in interference fit contact with the motor shaft 20. Among them, the three evenly arranged braking arms 322 surround the circumferential surface of the motor shaft 20 circumferentially, so as to form a sliding friction between the motor shaft 20 and the braking arms 322 during the rotational operation of the motor shaft 20. When observed from the side of the braking arm 322 facing the motor shaft 20, the braking arm 322 is configured to be concave in an arc shape, so that the arc extension direction of the braking arm 322 generally matches the circumferential surface of the motor shaft 20, so that the braking arm 322 contacts the motor shaft 20 with as large a contact surface as possible, and a braking surface as large as possible is established between the two to improve the braking force. In addition, the protruding arm 321 of each braking element 31 extends obliquely with respect to the radial direction R of the base body 31. This shape makes it easier for the braking element 32 to tilt in a certain direction, so as to realize directional adjustment of the braking force.

[0042] Of course, in an embodiment not shown, the protruding arm 321 may also extend along the radial direction R of the base body 31.

[0043] The electric motor 1 may further include a front end plate 16 axially mounted in front of the front end cover 12 along the axial direction x. As Figure 9 and Figure 10 shown, the front end plate 16 includes a cavity for partially accommodating the section of the motor shaft 20 protruding from the motor housing 10 and the braking device 30 mounted on the motor shaft 20.

[0044] To fixedly mount the braking device 30 relative to the motor shaft housing 10, the braking device 30 further includes a holding portion 33 disposed on the base body 31. The holding portion 33 may be fixedly connected to the outer surface of the base body 31 and protrude radially outward from the outer surface of the base body 31 along the radial direction R. According to an alternative embodiment not shown, the holding portion 33 may also be fixedly connected to the end side or the inner surface of the base body 31.

[0045] In this embodiment, two holding portions 33 are disposed opposite to each other on the base body 31. This symmetric design enables a simpler installation process. The front end plate 16 includes a receiving channel 160, and correspondingly, a clamping groove adapted to the holding portion 33 is formed on the inner wall of the receiving channel 160. The holding portion 33 is received in the clamping groove in a form-fitting manner while abutting against the front bearing 40 with its end side, thereby preventing the braking device 30 from moving axially x in the direction of the front end cover 12 or the front end plate 16 on the one hand, and preventing the braking device 30 from rotating with the motor shaft 20 on the other hand.

[0046] The above description has fully disclosed the specific embodiments of the present invention. It should be noted that any modification made by those skilled in the art to the specific embodiments of the present invention does not depart from the scope of the claims of the present invention. Accordingly, the scope of the claims of the present invention is not limited solely to the foregoing specific embodiments.

Claims

1. A braking device (30) for an electric motor (1), the electric motor (1) comprising a motor housing (10) and a motor shaft (20) extending axially (x) from the motor housing (10), characterized in that, The braking device (30) includes an annular base body (31) and at least two elastically deformable braking elements (32). Among them, the base body (31) includes a continuous outer surface, and the braking elements (32) protrude inward from the inner surface of the base body (31) and are in interference fit contact with the motor shaft (20), so as to form a sliding friction between the motor shaft (20) and the braking elements (32) during the rotational operation of the motor shaft (20).

2. The braking device (30) according to claim 1, characterized in that, The braking device (30) is of an integral structure.

3. The braking device (30) according to claim 1, characterized in that, At least part of the base body (31) includes a cylindrical outer surface.

4. The braking device (30) according to claim 1, characterized in that, The braking elements (32) are uniformly arranged along the circumference of the inner surface of the base body (31) at the same angular distance.

5. The braking device (30) according to claim 4, characterized in that, The braking device (30) includes three braking elements (32).

6. The braking device (30) according to claim 1, characterized in that, The braking element (32) includes a protruding arm (321) extending inward from the inner surface of the base body (31) and a braking arm (322) connected to the protruding arm (321). Among them, the braking arm (322) is configured to be in frictional contact with the motor shaft (20).

7. The braking device (30) according to claim 6, characterized in that, The braking arm (322) is configured to be concave in an arc shape.

8. The braking device (30) according to claim 6, characterized in that, Each of the braking elements (32) includes two protruding arms (321) and one braking arm (322) connecting the two protruding arms (321).

9. The braking device (30) according to claim 8, characterized in that, When observing in the direction from the outside to the inside along the radial direction (R) of the braking device (30), the distance between the two protruding arms (321) of the braking element (32) gradually increases.

10. The braking device (30) according to claim 6, characterized in that, Each of the braking elements (32) includes one protruding arm (321) and one braking arm (322) connected to the protruding arm (321).

11. The braking device (30) according to claim 10, characterized in that, The protruding arm (321) extends obliquely with respect to the radial direction (R) of the braking device (30).

12. The braking device (30) according to claim 1, characterized in that, When observing in the axial direction (x) of the braking device (30), the braking elements (32) extend within the base body (31).

13. The braking device (30) according to claim 1, characterized in that, The braking device (30) further includes at least one holding part (33) arranged on the base body (31), and the braking device (30) is fixedly installed relative to the motor housing (10) by using the holding part (33).

14. The braking device (30) according to claim 13, characterized in that, Two holding parts (33) are arranged on the base body (31).

15. A motor, characterized in that, The motor includes a motor housing, a motor shaft, and the braking device (30) according to any one of claims 1 to 14 above.

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