Infrasound generating device driven by stepper motor

Abstract

The present invention discloses an infrasound generating device driven by a stepper motor, characterized in that the device comprises: a Bluetooth module, an MCU, a stepper motor controller, a stepper motor driver, and a stepper motor infrasound speaker. The intensity of the infrasound generated by the device is controlled by changing the travel distance of the stepper motor or the caliber of the infrasound speaker vibration membrane; the frequency of the generated infrasound is changed by changing the stepper motor reversing time interval. The infrasound generating device has the advantages of simple working principle, simple structure, convenient manufacture, small size, and compact structure.

Description

Technical Field

[0001] The invention relates to the technical fields of circuits, motors and infrasound, in particular to an infrasound wave generating device driven by a stepping motor. Background Art

[0002] Infrasound is a wave below 20Hz, which is lower than the bass hearing range of human ears. Infrasound can be used in the medical field. For example, the Infrasound 8TM and Infrasound 8000 therapeutic instruments developed by CHI in the United States can randomly emit infrasound below 90dB, and are approved by the US FDA. They have many functions such as improving microcirculation, increasing immunity, anti-inflammatory, analgesic, and sedative sleep, and are widely used in clinical practice. For another example, the α wave music sound field produced by the infrasound band and the α wave close to the brain wave and music has significant effects on improving memory and improving sleep. With the continuous deepening of the scientific community's research on infrasound, the advantages of infrasound such as long propagation distance, strong penetration ability, and no interference from the electromagnetic environment have gradually been discovered by people, and its application in industrial production, medical and health care, environmental monitoring, military and political aspects has also attracted people's attention.

[0003] A stepper motor is an electromechanical actuator that converts an electrical pulse signal into a corresponding angular displacement. Each time an electrical pulse is input, it rotates through a fixed angle. The angular displacement of a stepper motor is proportional to the number of input pulses, that is, its speed is related to the pulse frequency and step angle. By controlling the input pulse frequency and number, and the connection sequence of each phase winding of the motor, the motor's single angular displacement speed and rotation direction can be controlled. The existence of this linear relationship, coupled with the characteristics of stepper motors that only have periodic errors but no cumulative errors, makes it very simple to use stepper motors to control speed, position and other control fields. In addition, the stepper motor open-loop control system has the advantages of simple structure, stability, reliability, easy control and low cost.

[0004] A loudspeaker is an effective way to generate infrasound. It uses electric current to excite the vibration of the diaphragm of the infrasound speaker, thereby generating infrasound waves of a certain frequency. However, the defects of existing loudspeakers and other methods of generating infrasound are that the infrasound generating device is large in size and has low transducer efficiency. In particular, when infrasound is used in the medical field, the existing laboratory infrasound wave generating devices have the problems of large structure, heavy use, complex structure, and high cost, and are not suitable for clinical operation. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a stepper motor driven infrasound wave generating device. The stepper motor driven infrasound wave generating device comprises: a Bluetooth module, an MCU, a stepper motor controller, a stepper motor driver, and a stepper motor infrasound speaker:

[0006] The Bluetooth module is used to communicate data with smart devices;

[0007] The MCU is used to run the control program of the infrasound wave generating device through the input and output interface;

[0008] The stepper motor controller is used to control the rotation of the motor according to the control pulse and the control signal;

[0009] The stepper motor driver is used to drive the stepper motor to rotate;

[0010] The stepper motor infrasonic speaker is used for the stepper motor to generate reciprocating linear motion under the control of an electrical signal, thereby driving the vibration membrane to generate infrasonic waves.

[0011] According to one aspect of the present invention, the stepper motor infrasonic speaker is driven by the stepper motor to rotate, driving the inner sleeve on the screw rod to linearly extend and retract along the outer sleeve, thereby driving the vibration membrane attached to one end of the inner sleeve to vibrate and generate infrasonic waves.

[0012] Preferably, when the infrasonic amplitude of the speaker is zero, the inner sleeve stops at the midpoint of the outer sleeve, and the vibration membrane is in a freely released state.

[0013] Furthermore, within the infrasonic wave cycle, the stepper motor drives the inner sleeve to move outward from the midpoint to the farthest point from the outer sleeve; then moves back from this point through the midpoint, and continues to move to the point where the inner sleeve is closest to the outer sleeve; then moves back to the midpoint, completing a cycle of vibration, and the vibration membrane generates a cycle of infrasonic waves.

[0014] Furthermore, the stepper motor drives the inner sleeve to move outward in a straight line until it reaches the farthest point, generating [0, ] interval infrasound; the stepper motor drives the inner sleeve to move back in a straight line, returning to the midpoint, generating [ , ] interval infrasound; the stepper motor drives the inner sleeve to move beyond the midpoint to the farthest point at the bottom of the outer sleeve, generating [ , ] interval infrasound; the stepper motor drives the inner sleeve back to the midpoint, generating [ , ] interval infrasound.

[0015] According to another aspect of the present invention, the frequency of the infrasonic waves generated by the vibration of the infrasonic horn is determined by the reversing time interval of the movement of the inner sleeve.

[0016] Furthermore, the frequency of the infrasonic waves generated by the vibration of the infrasonic speaker is determined by the commutation time interval of the stepping motor.

[0017] Furthermore, the time length of generating one cycle of infrasound is , [ , ]Start, in Point reversing , ], then Commutation , ],exist Time returns to the midpoint, producing a complete cycle of infrasound.

[0018] Furthermore, the frequency of the generated infrasound wave is calculated by the following formula:

[0019] (1).

[0020] Further, the commutation time of the stepper motor is changed , the infrasound frequency generated by the infrasound speaker also changes accordingly.

[0021] According to another aspect of the present invention, the vibration amplitude of the infrasonic speaker driven by the stepper motor is controlled by the moving distance of the inner sleeve in linear motion. The greater the moving distance, the greater the vibration amplitude and the stronger the radiation energy.

[0022] Furthermore, by controlling the rotation angle of the stepper motor within an infrasonic wave cycle, the maximum linear motion stroke of the inner sleeve is controlled, thereby controlling the intensity of the infrasonic sound generated by the infrasonic speaker.

[0023] Furthermore, by increasing the number of control pulses of the stepper motor within the infrasonic wave period, the rotation angle of the stepper motor can be controlled, thereby allowing the infrasonic speaker to generate stronger infrasonic waves.

[0024] Further, the stepper motor rotation angle is calculated by the following formula:

[0025] (2)

[0026] It is the rotation angle per unit pulse of the stepper motor.

[0027] Preferably, the vibration amplitude of the infrasonic speaker is also determined by the diameter of the vibration membrane. The larger the size, the stronger the radiation energy generated by the vibration.

[0028] Furthermore, the larger the diameter of the vibration membrane is, the greater the thrust required is, and the greater the motor power of the stepper motor is.

[0029] Preferably, when a sufficiently small speaker size and a sufficiently small stepping motor are selected, the infrasound wave generating device can be made very small, and can be made into an α-wave music playing earphone together with an ordinary music earphone.

[0030] Preferably, when a sufficiently large speaker size and a stepper motor with sufficiently large thrust are selected, the infrasound wave generating device can generate very strong infrasound waves, which can be used in other scientific devices requiring strong infrasound.

[0031] The beneficial effects of the above technical solution of the present invention are as follows:

[0032] The present invention provides an infrasound wave generating device driven by a stepper motor, wherein the stepper motor drives a vibrating membrane to generate infrasound waves. Compared with other existing technologies and devices, the device has the advantages of small size and simple structure. The frequency and intensity of the generated infrasound waves can be conveniently controlled by controlling the commutation time interval of the stepper motor and the control pulse frequency. The device has important application value in the medical field and many scientific fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is the structural principle of the stepping motor infrasound wave generating device of the preferred embodiment of the present invention;

[0034] Figure 2 It is the principle of generating infrasound waves by the stepping motor infrasound speaker of the preferred embodiment of the present invention;

[0035] Figure 3 It is a stepping motor infrasound speaker structure of a preferred embodiment of the present invention;

[0036] Figure 4 This is the working process of the stepping motor infrasound wave generating device of the preferred embodiment of the present invention. DETAILED DESCRIPTION

[0037] The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments. These drawings are simplified schematic diagrams, which only illustrate the basic principles, basic structures and basic functions of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0038] A person skilled in the art may be aware of some variations and equivalent substitutions of the present invention, but these variations and equivalent substitutions should not be construed as exceeding the protection scope of the present invention.

[0039] Figure 1 This is the structural principle of the stepping motor infrasound wave generating device of the preferred embodiment of the present invention. Figure 1 As shown, the stepper motor driven infrasound generating device comprises: a Bluetooth module 1, an MCU 2, a stepper motor controller 3, a stepper motor driver 4, and a stepper motor infrasound speaker 5:

[0040] The Bluetooth module 1 is used to communicate data with a smart device, and obtain preset infrasound frequency and intensity parameters to be generated by the infrasound generating device from the smart device;

[0041] The MCU 2 is used to run programs, control the infrasound wave generating device and provide input and output interfaces;

[0042] The stepper motor controller 3 controls the motor to rotate a fixed angle after receiving each control pulse, and controls the stepper motor to rotate and reverse after receiving a reversing instruction; the selection control instruction and the reversing control instruction are amplified by the motor driver 4, and then the stepper motor is driven to complete the corresponding rotation and reversing; finally, the stepper motor drives the inner sleeve of the infrasonic speaker 5 to make reciprocating linear motion, thereby driving the vibration membrane to vibrate periodically to generate infrasonic waves.

[0043] Figure 2 This is the principle of the stepper motor infrasound speaker generating infrasound waves in the preferred embodiment of the present invention. Figure 2 As shown, the stepper motor infrasound speaker 5 is driven by the stepper motor 21 to rotate, driving the inner sleeve 25 on the screw rod 23 to linearly extend and retract along the outer sleeve 22, thereby driving the vibration membrane attached to one end 26 of the inner sleeve to vibrate and generate infrasound waves. In the embodiment of the present invention, when the amplitude of the infrasound wave is zero, the nut of the inner sleeve 25 stops at the midpoint of the outer sleeve 22; within one infrasound wave cycle, the stepper motor 21 drives the nut of the inner sleeve 25 to move outward from the midpoint to the farthest end, and then moves back through the midpoint to the point where the nut 25 is closest to the bottom of the outer sleeve 22, and finally returns to the midpoint, completing a cycle of motion, driving the vibration membrane to generate a cycle of infrasound waves. In the embodiment of the present invention, 21 drives 25 to move outward in a straight line, so that 26 reaches the farthest point, generating [0, ] interval infrasound; 21 reverses and drives 25 to move back in a straight line, returning to the midpoint, generating [ , ] interval infrasound; 21 continues to drive 25 to move across the midpoint to the bottom of the outer sleeve 22 to the farthest point, generating [ , ] interval infrasound; 21 reverses again, driving the inner sleeve back to the midpoint, generating [ , ] interval infrasound. Figure 2 As shown, the frequency of the infrasound generated by the device is determined by the movement reversing time interval of the inner sleeve 25, that is, by the rotation reversing time interval of the stepper motor. The shorter the reversing time interval, the higher the frequency of the infrasound generated. In the embodiment of the present invention, it is assumed that an infrasound cycle is , is one quarter cycle of the infrasound wave. During this period, 25 rotates and moves outward with 21. Time point reversal; , ] during the period, move to the point closest to the bottom of 22, Time point reversal; , ] during the period of moving back, When time returns to the midpoint, a complete cycle of infrasound is generated. Therefore, the frequency of the generated infrasound is calculated by the following formula:

[0044] (3).

[0045] Figure 3 This is a stepper motor subsonic speaker structure of a preferred embodiment of the present invention. Figure 3 As shown, the stepper motor speaker driver 31, the top of the inner sleeve of 31 is bonded to the vibration membrane 33, and 31 and 33 are installed on the basin frame 32. When the stepper motor of 31 rotates, the inner sleeve is driven to move outward, pushing 33 outward; when the inner sleeve of 31 retracts inward, 33 is pulled inward, passing the midpoint to the lowest point, that is, the inner sleeve of 31 is closest to the bottom of the outer sleeve; finally, the inner sleeve of 31 returns to the midpoint, and 33 also returns to the static position. The intensity of the infrasonic wave generated by the infrasonic speaker is determined by the caliber of 33 and the travel distance of the inner sleeve moving outward. In the embodiment of the present invention, the larger the caliber of 33, the larger the travel of the inner sleeve of 31, and the greater the intensity of the infrasonic wave generated; when the caliber of 33 is very small, 31 is also made very small, and the infrasonic speaker can be placed in headphones.

[0046] Obviously, increasing the control pulse frequency can increase the The rotation angle of the stepper motor is increased, so that the infrasonic speaker produces stronger infrasonic waves. The rotation angle of the stepper motor is calculated by the following formula:

[0047] (3)

[0048] It is the rotation angle per unit pulse of the stepper motor, which is determined by the characteristics of the stepper motor.

[0049] Figure 4 This is the working process of the stepping motor infrasound wave generating device of the preferred embodiment of the present invention. Figure 4 The workflow is as follows:

[0050] S11: MCU receives the infrasound frequency set by the smart device received by the Bluetooth / WiFi module and intensity parameters ;

[0051] S12: According to calculate (commutation control interval); then according to calculate Number of control pulses per time interval , used to control the angular displacement of the stepper motor at a specified frequency and intensity, setting ;

[0052] S13: The motor rotates counterclockwise to move the inner sleeve nut to the point closest to the bottom of the outer sleeve. ;

[0053] S14: Control pulse to control the stepper motor to rotate clockwise , ;

[0054] S15: Determine the number of control pulses, i.e. the rotation step angle. , if satisfied (has not reached the farthest point), return to S14; if not satisfied (reached the farthest point), enter S16;

[0055] S16: Motor rotation reversing, ;

[0056] S17: Control pulse to control the stepper motor to rotate counterclockwise , ;

[0057] S18: Judgment , if satisfied, return to S17; if not satisfied (reach the farthest point in the opposite direction);

[0058] S19: , enter S20;

[0059] S20: Is it finished? If not finished (continue to generate the next infrasound wave), return to S14; if finished, enter S21;

[0060] S21: The motor rotates clockwise , return to the midpoint, release the diaphragm and return to the origin;

[0061] S22: End.

[0062] With the above embodiments of the present invention as inspiration, through the above description, relevant staff can make various changes and modifications without departing from the technical concept of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A stepper motor driven infrasound wave generating device, characterized in that: The device includes: a Bluetooth module, an MCU, a stepper motor controller, a stepper motor driver, and a stepper motor infrasound speaker: The Bluetooth module is used to communicate data with the intelligent control device; The MCU is used to control the infrasound wave generating device and provide an input and output interface; The stepper motor controller is used to control the rotation of the motor according to the control pulse; The stepper motor driver is used to drive the stepper motor to rotate; The stepper motor infrasound speaker is used to drive the vibration membrane to produce reciprocating linear movement under the control of the electrical signal to generate infrasound waves; The stepper motor infrasound speaker is driven by the rotation of the stepper motor to drive the inner sleeve on the screw rod to linearly extend and retract along the outer sleeve, thereby driving the vibration membrane attached to one end of the inner sleeve to generate infrasound waves; The intensity of the infrasonic waves produced by the infrasonic speaker is determined by the diameter of the vibrating membrane and the distance the inner sleeve moves outward.

2. The infrasound wave generating device driven by a stepper motor according to claim 1, characterized in that: The stepper motor drives the inner sleeve to move outward in a straight line to reach the farthest point, generating infrasound waves in the interval [0,π / 2]; the stepper motor drives the inner sleeve to move back in a straight line to return to the midpoint, generating infrasound waves in the interval [π / 2,π]; the stepper motor drives the inner sleeve to move beyond the midpoint and continue to move toward the bottom of the outer sleeve to the farthest point, generating infrasound waves in the interval [π,π3 / 2]; the stepper motor drives the inner sleeve to return to the midpoint, generating infrasound waves in the interval [π3 / 2,2π].

3. The infrasound wave generating device driven by a stepper motor according to claim 1, characterized in that: The frequency of the infrasound waves generated by the device is determined by the rotation reversing time interval of the stepping motor. The shorter the reversing time interval, the higher the frequency of the infrasound waves generated.

4. The infrasound wave generating device driven by a stepper motor according to claim 1, characterized in that: The amplitude of the infrasound waves generated by the device is controlled by the distance of the linear motion of the inner sleeve. The greater the distance of movement, the greater the vibration amplitude and the stronger the radiation energy. By controlling the rotation angle of the stepper motor within an infrasound wave cycle, the maximum linear motion stroke of the inner sleeve can be controlled, thereby controlling the infrasound intensity generated by the infrasound speaker.

5. The infrasound wave generating device driven by a stepper motor according to claim 1, characterized in that: The size of the diaphragm of the infrasonic speaker can be changed to control the intensity of the infrasonic waves generated by the device.

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