Brushless motor system and treadmill employing the same

Abstract

The application relates to the motor technical field and discloses a brushless motor system and a treadmill adopting the system. The brushless motor system comprises an inner rotation brushless motor, an induction module and a mounting module. An NS pole magnet is fixedly installed on an output shaft of the inner rotation brushless motor. The NS pole magnet cooperates with the induction module to perform non-contact induction sampling. The induction module is fixed at an end of the mounting module and the output shaft of the inner rotation brushless motor. An anti-interference module is arranged between the mounting module and the inner rotation brushless motor. When vibration is generated, the anti-interference module drives the induction module and the NS pole magnet to keep central alignment, the induction collection part of the induction module cannot be separated from the collection area, the magnetic field sampling is continuous, and the stability of an encoder output signal is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the motor technology field, more particularly, it relates to a brushless motor system and a treadmill using the same. BACKGROUND

[0002] The motor of the treadmill needs to cope with different exercise modes, such as walking, running, intermittent running, etc., which require the motor to run at different speeds and loads. In order to ensure smooth transition of these modes and avoid unexpected shutdown or power shortage, precise speed and position feedback of the motor of the treadmill is required to improve control accuracy.

[0003] Using an encoder to sample the rotating state of the motor has been maturely applied in treadmills, but the traditional encoder has wear and maintenance problems due to its contact design with the motor shaft, which limits its use in high-speed applications. Therefore, it is necessary to provide an integrated system of a brushless motor and a high-speed induction module to realize non-contact induction sampling and improve durability and measurement accuracy.

[0004] The magnetic rotary encoder relies on magnetic field changes to detect the movement of the motor shaft. When sampling, if the sensing part of the magnetic rotary encoder is not aligned with the center of the shaft, the magnetic field change received by the sensor will be irregular, resulting in signal distortion, affecting measurement accuracy, and causing magnetic field sampling to be discontinuous, thereby affecting the stability of the encoder output signal and causing system control errors. However, in actual use, due to the application of the motor sampling system in the treadmill, the high-speed rotation of the motor itself and the force of the human foot stepping on the treadmill will cause the motor to vibrate up and down in the vertical direction, causing some interference to the sampling work of the encoder. Therefore, how to eliminate the interference of vibration has become a problem to be solved in the application of the integrated system of the brushless motor and the high-speed induction module. SUMMARY

[0005] The present application provides a brushless motor system and a treadmill using the same, which solves the technical problem of interference of vibration caused by the high-speed rotation of the motor itself and the force of the human foot stepping on the treadmill on the sampling work of the encoder in the related art.

[0006] The present application provides a brushless motor system, which comprises an internal rotation brushless motor, an induction module and a mounting module. The output shaft of the internal rotation brushless motor is fixedly installed with an NS pole magnet. The NS pole magnet cooperates with the induction module to perform non-contact induction sampling.

[0007] The induction module is fixed to the opposite end of the mounting module and the output shaft of the internal rotation brushless motor. The mounting module and the internal rotation brushless motor are cooperated with an anti-interference module.

[0008] The anti-interference module comprises an outer frame, an inner frame and an automatic following assembly, the inner brushless motor is externally fixed with the inner frame, and the upper and lower end faces of the inner frame and the upper and lower end faces of the installation module are both provided with the automatic following assembly, when vibration occurs at the inner frame, the automatic following assembly drives the installation module to vibrate synchronously, so that the NS pole magnet and the induction module are kept in central alignment.

[0009] As a further scheme of the present application, the automatic following assembly comprises a first rotating shaft, a second rotating shaft, a first rotating disc, a second rotating disc, a synchronous belt, a winding wheel, a steel cable, a hanging joint and a torsion spring, the first rotating shaft and the second rotating shaft are both rotatably installed in the outer frame, the first rotating disc is fixedly arranged on the first rotating shaft, the second rotating disc is fixedly arranged on the second rotating shaft, the first rotating disc and the second rotating disc are matched by the synchronous belt, the winding wheel is fixedly installed on the first rotating shaft and the second rotating shaft, the steel cable is wound on the winding wheel, one side of the steel cable is fixed with the installation module through the hanging joint, and the other side of the steel cable is fixed with the inner frame, and the second rotating shaft and the outer frame are matched with the torsion spring.

[0010] As a further scheme of the present application, the induction module comprises a magnetic exciter and a sensor plate, the magnetic exciter corresponds to the NS pole magnet, and the sensor plate is used for reading the rotation signal of the magnetic exciter.

[0011] As a further scheme of the present application, the resolution provided by the induction module is greater than or equal to 12 bits.

[0012] As a further scheme of the present application, the resolution allows the output of 4096 angle increment signals per circumference.

[0013] As a further scheme of the present application, the sampling rotating speed supported by the induction module is greater than or equal to 30000 RPM.

[0014] As a further scheme of the present application, the working temperature range supported by the induction module is from -40 DEG C to 125 DEG C.

[0015] A treadmill adopts the above brushless motor system, and the brushless motor system is used as a built-in power component of the treadmill.

[0016] The present application has the following advantages:

[0017] When vibration occurs at the inner frame, the automatic following assembly drives the installation module to vibrate synchronously, so that the induction module and the NS pole magnet keep synchronous movement, so that the induction module and the NS pole magnet can keep central alignment even when vibration occurs, the induction collection part of the induction module does not deviate from the collection area, the magnetic field sampling is continuous, and the stability of the encoder output signal is improved.

[0018] The present application provides a non-contact sensing sampling method, which reduces wear and maintenance requirements.

[0019] The present application realizes high-precision position and speed feedback, and improves the control precision of the motor.

[0020] The present application is suitable for high-speed applications, and widens the use range of the motor. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a whole front view structural schematic diagram of the brushless motor system according to the present application;

[0022] Figure 2 is a whole three-dimensional structural schematic diagram of the brushless motor system according to the present application;

[0023] Figure 3 is a structural schematic diagram of the automatic following assembly in the brushless motor system according to the present application;

[0024] Figure 4 is a schematic diagram of the working principle of the brushless motor system according to the present application;

[0025] Figure 5 is a schematic diagram of the cooperation of the induction module and the NS pole magnet in the brushless motor system according to the present application;

[0026] Figure 6 is a schematic diagram of the sensor board in the brushless motor system according to the present application.

[0027] In the figure: 10, inner rotating brushless motor; 100, NS pole magnet; 20, induction module; 30, installation module; 40, anti-interference module; 401, outer frame; 402, inner frame; 43, automatic following assembly; 431, first rotating shaft; 432, second rotating shaft; 433, first rotating disc; 434, second rotating disc; 435, synchronous belt; 436, winding wheel; 437, steel cable; 438, hanging joint; 439, torsion spring. DETAILED DESCRIPTION

[0028] The subject matter described herein will now be discussed with reference to example implementations. It should be understood that discussions of these implementations merely summarize aspects of the subject matter described herein and should not be construed to limit the scope or content of the disclosure in any way. Various example implementations can omit, substitute, or add various procedures or components as appropriate. Also, it should be understood that instead of esting features described with respect to one example, features from two or more examples can be combined.

[0029] EMBODIMENT

[0030] The present application discloses a brushless motor system, such as Figure 1 -Figure 6 As shown, it includes an internal rotary brushless motor 10, a sensing module 20 and a mounting module 30. An N-pole magnet 100 is fixedly mounted on the output shaft of the internal rotary brushless motor 10. The N-pole magnet 100 cooperates with the sensing module 20 to perform non-contact sensing sampling.

[0031] The sensing module 20 is fixed at one end of the mounting module 30 and the output shaft of the internal brushless motor 10, and an anti-interference module 40 is provided between the mounting module 30 and the internal brushless motor 10.

[0032] The anti-interference module 40 includes an outer frame 401, an inner frame 402, and an automatic following component 43. The inner frame 402 is fixed to the outer side of the inner brushless motor 10. Automatic following components 43 are provided between the upper and lower end faces of the inner frame 402 and the upper and lower end faces of the mounting module 30. When vibration occurs at the inner frame 402, the automatic following component 43 drives the mounting module 30 to vibrate synchronously, so that the N and S pole magnets 100 and the sensing module 20 are kept aligned at the center.

[0033] For the integrated system of the brushless motor and the high-speed sensing module 20, vibration interference is eliminated through the anti-interference module 40. When the treadmill is in an idle state (no user applies any vibration), in the internal brushless motor 10 system, the sensing module 20 and the N / S pole magnet 100 are aligned. At this time, the sensing module 20 can accurately sense changes in the magnetic field. When the treadmill is in use, the force generated by the user's running motion is transmitted to the internal brushless motor 10, causing it to vibrate up and down. In practice, due to the sensing and acquisition unit of the sensing module 20... The sampling range of the position is smaller than the size of the NS pole magnet 100 and cannot completely cover it. When it vibrates up and down, the sensing and sampling part of the sensing module 20 will detach from the sampling area, resulting in sampling error. To eliminate this error, in this invention, when vibration occurs at the inner frame 402, the automatic follow component 43 drives the mounting module 30 to vibrate synchronously, so that the sensing module 20 and the NS pole magnet 100 move synchronously. In this way, even when vibration occurs, the sensing module 20 and the NS pole magnet 100 can still maintain center alignment, and the sensing and sampling part of the sensing module 20 will not detach from the sampling area, ensuring continuous magnetic field sampling and improving the stability of the encoder output signal.

[0034] like Figure 3As shown, the automatic following assembly 43 comprises a first rotating shaft 431, a second rotating shaft 432, a first rotating disc 433, a second rotating disc 434, a synchronous belt 435, a winding wheel 436, a steel cable 437, a hanging joint 438 and a torsion spring 439. The first rotating shaft 431 and the second rotating shaft 432 are both rotatably installed in the outer frame 401. The first rotating disc 433 is fixedly arranged on the first rotating shaft 431. The second rotating disc 434 is fixedly arranged on the second rotating shaft 432. The first rotating disc 433 and the second rotating disc 434 are matched through the synchronous belt 435. The winding wheel 436 is fixedly installed on the first rotating shaft 431 and the second rotating shaft 432. The steel cable 437 is wound on the winding wheel 436. One side of the steel cable 437 is fixed with the installation module 30 through the hanging joint 438. The other side of the steel cable 437 is fixed with the inner frame 402. The second rotating shaft 432 is matched with the torsion spring 439 between the outer frame 401.

[0035] The specific implementation that the induction module 20 keeps synchronous movement with the NS pole magnet 100 is realized through the automatic following assembly 43. When the inner rotating brushless motor 10 itself runs to generate up-down vibration and the user uses the treadmill to generate up-down vibration acting on the inner rotating brushless motor 10, the inner frame 402 will pull the steel cable 437. The movement of the steel cable 437 drives the winding wheel 436 to rotate, converts the linear motion of the up-down vibration into rotary output, thereby driving the second rotating shaft 432 to rotate. When the second rotating shaft 432 rotates, the synchronous rotating structure formed by the combination of the first rotating disc 433, the second rotating disc 434 and the synchronous belt 435 makes the first rotating shaft 431 generate the same rotation amount. In this way, the steel cable 437 on the side of the first rotating shaft 431 also generates the same up-down movement amount. In this way, the installation module 30 fixed through the hanging joint 438 generates synchronous up-down movement, that is, the induction module 20 keeps synchronous movement with the NS pole magnet 100, thereby eliminating the interference influence generated by the vibration.

[0036] It needs to be specially pointed out that, in the above, the torsion spring 439 is matched and arranged at the rotary connection end of the second rotating shaft 432, so as to provide the second rotating shaft 432 with rotation return capability.

[0037] The induction module 20 comprises a magnetic exciter and a sensor plate. The magnetic exciter corresponds to the NS pole magnet 100. The sensor plate is used for reading the rotation signal of the magnetic exciter.

[0038] The principle of the induction module 20 for non-contact induction sampling of the output shaft of the inner rotating brushless motor 10 includes the following specific implementations:

[0039] I. Hall effect sensing:

[0040] The sensor board is a Hall sensor, which determines the angle, speed or position of the shaft by detecting the change of the magnetic field on the shaft. A small magnet or magnetic marker (NS magnet 100) is installed on the output shaft of the inner rotating brushless motor 10, and the NS magnet 100 rotates with the output shaft of the inner rotating brushless motor 10. Due to the corresponding magnetic excitation body and NS magnet 100, synchronous rotation is generated. The Hall sensor detects the change of the magnetic field generated by the rotation of the magnetic excitation body, thereby calculating the specific position or speed of the output shaft of the inner rotating brushless motor 10.

[0041] Through the Hall effect sensor, it is widely used in position feedback, speed monitoring, angle sensing and other aspects in motor control system.

[0042] Second, magnetic encoder:

[0043] The non-contact measurement method combines magnetic induction and encoding technology. In this application, the sensor board has a built-in encoder counting module. A coding disc (NS magnet 100) with magnetic material is installed on the output shaft of the inner rotating brushless motor 10. When the output shaft of the inner rotating brushless motor 10 rotates, the magnetic material changes the distribution of the surrounding magnetic field. The sensor board detects these changes and compares them with the built-in encoder counting module to generate corresponding angle or position information.

[0044] Through the magnetic encoder, it is widely used in high-precision angle measurement, position detection and speed control system of motor rotating shaft.

[0045] The resolution provided by the sensing module 20 is greater than or equal to 12 bits.

[0046] The sampling speed supported by the sensing module 20 is greater than or equal to 30000 RPM.

[0047] The working temperature range supported by the sensing module 20 is from -40℃ to 125℃.

[0048] The above describes the embodiments of the present application, but the embodiments are not limited to the specific implementation described above. The specific implementation described above is only illustrative and not limiting. Those skilled in the art can make more forms of equivalent embodiments under the inspiration of the embodiments, which are all within the protection scope of the embodiments.

Claims

1. A brushless motor system, characterized in that, Includes an internal rotary brushless motor (10), a sensing module (20) and an installation module (30). An N-pole magnet (100) is fixedly installed on the output shaft of the internal rotary brushless motor (10). The N-pole magnet (100) cooperates with the sensing module (20) to perform non-contact sensing sampling. The sensing module (20) is fixed at one end of the mounting module (30) and the output shaft of the inner brushless motor (10), and an anti-interference module (40) is provided between the mounting module (30) and the inner brushless motor (10). The anti-interference module (40) includes an outer frame (401), an inner frame (402), and an automatic following component (43). The inner frame (402) is fixed to the outside of the inner brushless motor (10). The automatic following component (43) is provided between the upper and lower end faces of the inner frame (402) and the upper and lower end faces of the mounting module (30). When vibration occurs at the inner frame (402), the automatic following component (43) drives the mounting module (30) to vibrate synchronously, so that the NS pole magnet (100) and the sensing module (20) remain aligned in the center. The automatic following assembly (43) includes a first rotating shaft (431), a second rotating shaft (432), a first turntable (433), a second turntable (434), a timing belt (435), a winding reel (436), a steel strand (437), a lifting connector (438), and a torsion spring (439). The first rotating shaft (431) and the second rotating shaft (432) are both rotatably mounted in the outer frame (401). The first turntable (433) is fixedly mounted on the first rotating shaft (431), and the second turntable (434) is fixedly mounted on the second rotating shaft (432). The first turntable (433) and the second turntable (434) are connected by a synchronous belt (435). Both the first shaft (431) and the second shaft (432) are fixedly mounted with winding wheels (436). Steel strands (437) are wound on the winding wheels (436). One side of the steel strands (437) is fixed to the installation module (30) through a lifting joint (438), and the other side of the steel strands (437) is fixed to the inner frame (402). A torsion spring (439) is connected between the second shaft (432) and the outer frame (401).

2. The brushless motor system according to claim 1, characterized in that, The sensing module (20) includes a magnetic exciter and a sensor board. The magnetic exciter corresponds to the N and N pole magnets (100), and the sensor board is used to read the rotation signal of the magnetic exciter.

3. The brushless motor system according to claim 1, characterized in that, The sensing module (20) provides a resolution of 12 bits or more.

4. The brushless motor system according to claim 3, characterized in that, The resolution allows for the output of 4096 angular increment signals per circumference.

5. The brushless motor system according to claim 1, characterized in that, The sensing module (20) supports a sampling speed of ≥30000RPM.

6. The brushless motor system according to claim 1, characterized in that, The sensing module (20) supports an operating temperature range of -40°C to 125°C.

7. A treadmill employing a brushless motor system as described in any one of claims 1 to 6, characterized in that, The internal brushless motor (10) system of the treadmill is a built-in power component of the treadmill.

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