A shock absorbing brushless motor for fitness equipment

Abstract

The application discloses a shockproof brushless motor for a fitness equipment, which comprises a stator and a rotor, the stator comprises a central core shaft and an outer winding core, the rotor is located outside the winding core and is connected through a bearing and the core shaft; a through hole is arranged in the center of the winding core, a core shaft sleeve is arranged inside the through hole, an annular mounting plate is arranged outside the core shaft, the mounting plate and the winding core are connected through bolts or pins, a sliding ring is slidably connected to the core shaft on the side of the mounting plate away from the winding core, a plurality of first connecting rods are hingedly connected to the sliding ring, the first connecting rods are hingedly connected to sliding blocks, the sliding blocks are slidably connected to sliding grooves, the sliding grooves are arranged on the winding core, springs and shock-absorbing blocks are arranged between the sliding ring and the mounting plate, and the springs and the shock-absorbing blocks are sleeved on the core shaft. The structure of the application can exert a pre-tightening force between the mounting plate and the winding core, increase the lateral friction force, reduce the lateral displacement amplitude between the mounting plate and the winding core, and further reduce the vibration and noise.

Description

Technical Field

[0001] This invention relates to the field of brushless motor technology, and specifically to a shockproof brushless motor for use in fitness equipment. Background Technology

[0002] Brushless DC motors have advantages such as simple structure, high efficiency, good speed regulation, and long service life, and have been widely used in fields such as robotics, drones, new energy vehicles, fitness equipment, and smart homes. The brushless motor body with an external rotating structure consists of an outer permanent magnet rotor and an inner winding stator. The permanent magnets on the rotor establish an excitation magnetic field, while the central windings in the stator slots generate an armature magnetic field. The interaction of these two magnetic fields produces a continuous driving torque, enabling the brushless motor to operate continuously.

[0003] A winding stator typically consists of an inner spindle and an outer winding core. The winding core is usually made of multiple stacked silicon steel sheets. The spindle is connected to the permanent magnet rotor via bearings, and the spindle and winding core are fixed with bolts or pins. However, uneven stress distribution at different fixing positions can cause slight lateral misalignment of the connected parts due to vibration. This can lead to slippage between the threaded surfaces, reduced friction, and bolt loosening. In more severe cases, it can cause axial loosening of the bolts, a sharp decrease in preload, and deformation of the connecting parts. Ultimately, this results in axial displacement of the stator and rotor, increasing motor vibration and noise, affecting motor stability, and damaging the stator structure through fatigue. This vibration is particularly noticeable in some fitness equipment, such as treadmills and exercise bikes, where the movement inevitably causes vibration. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a shock-resistant brushless motor for fitness equipment.

[0005] Technical solution:

[0006] A shock-resistant brushless motor for fitness equipment includes a stator and a rotor. The stator includes a central spindle and an outer winding core. The rotor is located outside the winding core and connected to the spindle via bearings. The winding core has a through hole at its center, and the spindle is fitted inside the through hole. An annular mounting plate is provided on the outer side of the spindle. The mounting plate and the winding core are connected by bolts or pins. A sliding ring is slidably connected to the spindle on the side of the mounting plate away from the winding core. Multiple first connecting rods are hinged to the sliding ring. The first connecting rods are hinged to sliders. The sliders are slidably connected to a sliding groove, which is provided on the winding core. A spring and a damping block are provided between the sliding ring and the mounting plate. Both the spring and the damping block are fitted onto the spindle.

[0007] Furthermore, a drive ring is rotatably connected to the spindle, the drive ring is fixedly connected to the rotor, and a plurality of second connecting rods are symmetrically hinged to the side of the drive ring. A weighted ball is fixed to the end of the second connecting rod, and a third connecting rod is hinged to the middle position of the second connecting rod. The third connecting rod is hinged to a rotating ring, and the rotating ring is rotatably connected to a sliding ring.

[0008] Furthermore, the slider has a T-shaped cross-section, which matches the T-shaped groove of the connecting groove. One end of the groove is a closed structure, and the other end is provided with a sealing block.

[0009] Furthermore, the rotor includes a front housing, an annular housing, and a rear housing. The two ends of the spindle extend from the central holes of the front housing and the rear housing to the outside, respectively. Multiple permanent magnets are arranged on the inner side of the annular housing. The permanent magnets are close to the winding slots on the outer side of the winding core. The mounting plate is located on one side of the rear housing, and the bearing is located inside the front housing.

[0010] Furthermore, the winding core is provided with a positioning groove in the middle, and the mounting plate is positioned and installed in the positioning groove. The bottom of the positioning groove is provided with multiple threaded holes or pin holes.

[0011] Furthermore, there are four first connecting rods, and two second connecting rods and two third connecting rods.

[0012] Furthermore, mounting portions are provided at both ends of the mandrel.

[0013] Furthermore, the front housing has a first connecting part in the middle and a second connecting part on the inner side. Each of the first and second connecting parts is provided with a bearing, and the bearing in the second connecting part is larger in size.

[0014] Beneficial effects:

[0015] This invention provides a shock-resistant brushless motor for fitness equipment. The stator spindle and winding core are connected by interference-fit bolts or pins. To prevent loosening of the interference fit due to vibration, a tensioning structure consisting of a sliding ring, a first connecting rod, a slider, and a groove is provided. The spring's thrust on the sliding ring drives the first connecting rod to tighten the winding core, and the spring's reaction force pushes the mounting plate, thus applying a preload between the mounting plate and the winding core. This preload, combined with shock-absorbing blocks, increases lateral friction, reduces the lateral misalignment between the mounting plate and the winding core, and can... To reduce or directly avoid axial displacement between the mounting plate and the winding core, and to further reduce the impact of vibration during brushless motor operation, a structure consisting of a drive ring, a second connecting rod, a weighted ball, a third connecting rod, and a rotating ring is further designed. The centrifugal force generated by the rotor rotation drives the weighted ball to swing, and the swinging second connecting rod pulls the sliding ring outward, ultimately creating a tendency to pull the winding core outward. This force increases the preload between the mounting plate and the winding core, making the connection less prone to loosening during brushless motor operation, thereby reducing the risk of rotor and stator misalignment and reducing vibration and noise. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the front external structure of the brushless motor of the present invention; Figure 2 This is a schematic diagram of the rear external structure of the brushless motor of the present invention; Figure 3 This is a schematic diagram of the internal structure of the brushless motor of the present invention after the housing is removed; Figure 4 This is a schematic diagram of the rear structure of the brushless motor of the present invention when the rotor is removed; Figure 5 This is a schematic diagram of the front structure of the brushless motor of the present invention when the rotor is removed.

[0017] In the diagram, 1. mandrel, 2. winding core, 3. mounting plate, 4. bolt, 5. sliding ring, 6. first connecting rod, 7. slider, 8. groove, 9. spring, 10. damping block, 11. drive ring, 12. second connecting rod, 13. weighted ball, 14. third connecting rod, 15. sliding ring, 16. sealing block, 17. front housing, 18. annular housing, 19. rear housing, 20. winding groove, 21. bearing, 22. threaded hole, 23. mounting part. Detailed Implementation

[0018] The present invention will now be described in detail with reference to the accompanying drawings.

[0019] As attached Figure 1 To be continued Figure 5 . Specific implementation examples:

[0021] A shockproof brushless motor for fitness equipment includes a stator and a rotor. The stator includes a central spindle 1 and an outer winding core 2. The rotor is located outside the winding core 2 and is connected to the spindle 1 via a bearing 21. The winding core 2 has a through hole in its center, and the spindle 1 is fitted inside the through hole. An annular mounting plate 3 is provided on the outer side of the spindle 1. The mounting plate 3 and the winding core 2 are connected by bolts 4 or pins. A sliding ring 5 is slidably connected to the spindle 1 on the side of the mounting plate 3 away from the winding core 2. Multiple first connecting rods 6 are hinged to the sliding ring 5. The first connecting rods 6 are hinged to sliders 7. The sliders 7 are slidably connected to a sliding groove 8. The sliding groove 8 is provided on the winding core 2. A spring 9 and a shock absorber 10 are provided between the sliding ring 5 and the mounting plate 3. Both the spring 9 and the shock absorber 10 are fitted onto the spindle 1.

[0022] Spring 9 is always in a compressed state. It acts on the sliding ring 5, pushing it outwards. The sliding ring 5 pulls the slider 7 via the first connecting rod 6. When the slider 7 stops sliding, the first connecting rod 6 is in a tensioned state. The reaction force of spring 9 acts on the mounting plate 3. Therefore, there is a preload between the mounting plate 3 and the winding core 2. This preload increases lateral friction, reduces the lateral misalignment between the mounting plate 3 and the winding core 2, and can reduce or directly prevent axial displacement between them. This preload is always present regardless of whether the brushless motor is working, thus resisting the influence of external vibrations on the interference fit of the bolts 4 or pins, reducing vibration and noise.

[0023] The vibration of a brushless motor is amplified when it is working. For example, when a treadmill is running, the vibration is amplified when a person runs on it. In order to further reduce the impact of vibration, the following structure is set up: a drive ring 11 is rotatably connected to the spindle 1, the drive ring 11 is fixedly connected to the rotor, and multiple second connecting rods 12 are symmetrically hinged to the side of the drive ring 11. A weight ball 13 is fixed to the end of the second connecting rod 12, and a third connecting rod 14 is hinged to the middle position of the second connecting rod 12. The third connecting rod 14 is hinged to the rotating ring 15, and the rotating ring 15 is rotatably connected to the sliding ring 5.

[0024] When the brushless motor is working, the drive ring 11 rotates synchronously with the rotor. Due to centrifugal force, the rotation of the drive ring 11 causes the second connecting rod 12 and the weighted ball 13 to tend to swing upwards, which further pulls the rotating ring 15 through the third connecting rod 14, thereby pulling the sliding ring 5. To resist this centrifugal force, the preload between the mounting plate 3 and the winding core 2 is increased, thereby increasing the friction and further resisting the impact of the increased vibration on the interference fit of the bolts 4 or pins, thus reducing vibration and noise.

[0025] Preferably, the slider 7 has a T-shaped cross-section, which matches the T-shaped opening of the connecting groove 8. One end of the groove 8 is a closed structure, and the other end is provided with a sealing block 16. When the spring 9 is tensioned, the slider 7 slides to the innermost side and is blocked by the sealing block 16. The T-shaped cross-section can prevent the slider 7 from falling out. The sealing block 16 is usually connected by screws or welding, while the groove 8 is integrally formed with the winding core 2.

[0026] Preferably, the rotor includes a front housing 17, an annular housing 18 and a rear housing 19. The two ends of the spindle 1 extend from the center holes of the front housing 17 and the rear housing 19 to the outside, respectively. A plurality of permanent magnets (not shown in the figure) are provided on the inner side of the annular housing 18. The permanent magnets are close to the winding groove 20 on the outer side of the winding core 2. The mounting plate 3 is located on one side of the rear housing 19, and the bearing 21 is located inside the front housing 17.

[0027] The winding core 2 has a positioning groove in the middle, and the mounting plate 3 is positioned and installed in the positioning groove. The bottom of the positioning groove has multiple threaded holes 22 or pin holes. The mounting plate 3 is used for positioning and installation to ensure the concentricity of the rotor and stator.

[0028] Preferably, there are four first connecting rods 6, and two second connecting rods 12 and two third connecting rods 14. Mounting portions 23 are provided at both ends of the spindle 1 for mounting the brushless motor.

[0029] The front housing 17 has a first connecting part in the middle and a second connecting part on the inner side. Each of the first and second connecting parts is provided with a bearing 21, and the bearing 21 in the second connecting part is larger in size.

[0030] The brushless motor of this invention is suitable for use in environments with significant vibration, such as fitness equipment like treadmills. It is small in size, powerful, and has fast heat dissipation. It uses an external brushless motor with a commonly used diameter of 125cm, a speed of 20,000 r / min, a power of 1,000w, and a conversion efficiency of over 98%.

[0031] Although the present invention has been disclosed above with reference to preferred embodiments, these are not intended to limit the invention. Any person skilled in the art can make various changes or modifications without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention should be defined by the scope of the claims of this application.

Claims

1. A shockproof brushless motor for fitness equipment, characterized in that, The device includes a stator and a rotor. The stator includes a central spindle and an outer winding core. The rotor is located outside the winding core and is connected to the spindle via bearings. The winding core has a through hole at its center, and the spindle is fitted inside the through hole. An annular mounting plate is provided on the outer side of the spindle. The mounting plate and the winding core are connected by bolts or pins. A sliding ring is slidably connected to the spindle on the side of the mounting plate away from the winding core. Multiple first connecting rods are hinged to the sliding ring. The first connecting rods are hinged to sliders. The sliders are slidably connected to a sliding groove, which is provided on the winding core. A spring and a damping block are provided between the sliding ring and the mounting plate. Both the spring and the damping block are fitted onto the spindle.

2. The shockproof brushless motor for fitness equipment according to claim 1, characterized in that, A drive ring is rotatably connected to the spindle, and the drive ring is fixedly connected to the rotor. Multiple second connecting rods are symmetrically hinged to the side of the drive ring. A weighted ball is fixed to the end of each second connecting rod. A third connecting rod is hinged to the middle of each second connecting rod. The third connecting rod is hinged to a rotating ring, and the rotating ring is rotatably connected to a sliding ring.

3. A shockproof brushless motor for fitness equipment according to claim 1 or 2, characterized in that, The slider has a T-shaped cross-section, which matches the T-shaped groove of the connecting groove. One end of the groove is a closed structure, and the other end is provided with a sealing block.

4. A shockproof brushless motor for fitness equipment according to claim 1, characterized in that, The rotor includes a front housing, an annular housing, and a rear housing. The two ends of the spindle extend from the center holes of the front housing and the rear housing to the outside, respectively. Multiple permanent magnets are arranged on the inner side of the annular housing. The permanent magnets are close to the winding slots on the outer side of the winding core. The mounting plate is located on one side of the rear housing, and the bearing is located inside the front housing.

5. A shockproof brushless motor for fitness equipment according to claim 1, characterized in that, The winding core has a positioning groove in the middle, and the mounting plate is positioned and installed in the positioning groove. The bottom of the positioning groove has multiple threaded holes or pin holes.

6. A shockproof brushless motor for fitness equipment according to claim 2, characterized in that, There are four first connecting rods, and two second connecting rods and two third connecting rods.

7. A shockproof brushless motor for fitness equipment according to claim 1, characterized in that, The mandrel has mounting parts at both ends.

8. A shockproof brushless motor for fitness equipment according to claim 4, characterized in that, The front housing has a first connecting part in the middle and a second connecting part on the inner side. Each of the first and second connecting parts is provided with a bearing, and the bearing in the second connecting part is larger.

Images