Dental implant machine and motor torque regulation method thereof

Abstract

The application provides a dental implant machine and a motor torque regulation method thereof. The output rotation speed of the motor in the dental implant machine is controlled by a rotation speed control loop of a main machine in the dental implant machine. In the motor torque regulation method, when the motor is stopped, the output of a PI controller in the rotation speed control loop is greater than zero, so the adjustment amount of the duty cycle in the rotation speed control loop is limited to zero, the output of the PI controller is limited to zero, the duty cycle output by the rotation speed control loop remains unchanged, and thus the output torque of the motor remains unchanged. Since the motor stop can indicate that the motor encounters a sudden load, the motor torque regulation method provided by the application can realize the motor torque maintenance function of the dental implant machine.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology, and in particular to a dental implant machine and a method for adjusting the torque of its motor. Background Technology

[0002] There are many factors that usually affect the success or failure of dental implant surgery, such as the hardware circuit design of the implant machine, the doctor's mastery of dental implant technology, the patient's bone condition, and postoperative care. Among these, the motor torque maintenance function of the dental implant machine is an important factor that has not been given much attention.

[0003] Specifically, motor torque maintenance function is the ability of a dental implant machine to maintain a constant output torque when its motor encounters a sudden change in load; however, dental implant machines on the market currently do not have torque maintenance function.

[0004] Therefore, how to achieve torque maintenance in dental implant machines is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] In view of this, the present invention provides a dental implant machine and a method for controlling the torque of its motor, so as to achieve the torque maintenance function of the dental implant machine.

[0006] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0007] This application provides a method for controlling the motor torque of a dental implant machine, wherein the output speed of the motor in the dental implant machine is controlled by a speed control loop of the main unit in the dental implant machine; the method for controlling the motor torque includes:

[0008] Determine whether the motor has stopped;

[0009] If the motor stops, the adjustment of the duty cycle in the speed control loop is limited to zero.

[0010] Optionally, after determining that the motor has stopped, the method further includes:

[0011] The commutation strategy in the host is reset to: the power supply voltage of the motor is commutated once every preset time interval.

[0012] Optional, the preset time is 40us.

[0013] Optionally, the speed control loop includes a proportional-integral (PI) controller; the PI algorithm executed by the PI controller includes:

[0014] Determine whether the previous output of the PI controller is less than or equal to the minimum value of the preset limit range;

[0015] If the previous output is less than or equal to the minimum value of the preset limit range, then the PI controller will only integrate the motor speed deviation in the speed control loop that is greater than zero this time.

[0016] If the previous output is greater than the minimum value of the preset limit range, then determine whether the previous output is greater than or equal to the maximum value of the preset limit range;

[0017] If the previous output is greater than or equal to the maximum value of the preset limit range, the PI controller will only integrate the motor speed deviation that is less than zero this time.

[0018] This application also provides a dental implant machine, comprising: a main unit and a motor; the main unit includes: an inverter circuit, a drive circuit, a controller, and three Hall position sensors; wherein:

[0019] The three Hall position sensors are installed inside the motor to detect the position of the rotor in the motor; the output terminals of the three Hall position sensors are respectively connected to the corresponding signal receiving terminals of the controller.

[0020] The AC side of the inverter circuit is connected to the motor; the control terminal of the inverter circuit is connected to the signal output terminal of the controller through the drive circuit, and is controlled by the speed control loop in the controller.

[0021] The controller is used to perform the motor torque control method for a dental implant machine as described in any of the preceding aspects of this application.

[0022] Optionally, it also includes: a multi-functional foot pedal; the main unit further includes: a speed module; wherein:

[0023] The controller is used to determine the set speed of the motor based on the real-time voltage of the multi-functional pedal sampled by the speed module.

[0024] Optionally, the host further includes: three hardware low-pass filter circuits; wherein:

[0025] The three Hall position sensors are each connected to the controller through a corresponding hardware low-pass filter circuit.

[0026] Optionally, the hardware low-pass filter circuit includes: a resistor branch and a capacitor branch; wherein:

[0027] One end of the resistor branch is connected to one end of the capacitor branch, and the connection point serves as the output terminal of the hardware low-pass filter circuit.

[0028] The other end of the resistor branch serves as the input terminal of the hardware low-pass filter circuit, and the other end of the capacitor branch is grounded.

[0029] Optionally, the speed control loop further includes: a digital filtering module; wherein:

[0030] The digital filtering module is positioned before the input of the PI controller in the speed control loop.

[0031] Optionally, the output of the digital filtering module is equal to the weighted sum of the previous output and the current input of the digital filtering module.

[0032] As can be seen from the above technical solution, the present invention provides a method for regulating the motor torque of a dental implant machine, wherein the output speed of the motor in the dental implant machine is controlled by the speed control loop of the main unit in the dental implant machine. In this motor torque regulation method, since the output of the PI controller in the speed control loop is greater than zero when the motor stops, limiting the adjustment of the duty cycle in the speed control loop to zero can limit the output of the PI controller to zero, thus keeping the duty cycle of the speed control loop output unchanged, thereby maintaining the output torque of the motor constant; and since the motor stopping indicates that the motor has encountered a sudden load change, the motor torque regulation method provided in this application can realize the motor torque maintenance function of the dental implant machine. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0034] Figure 1 A control block diagram of one implementation of a speed control loop;

[0035] Figure 2 and Figure 3 These are schematic flowcharts illustrating two implementation methods of the motor torque control method for a dental implant machine provided in this application.

[0036] Figure 4 A flowchart illustrating a PI algorithm executed by the PI controller provided in an embodiment of this application;

[0037] Figures 5-11 These are schematic diagrams illustrating seven different implementations of the dental implant machine provided in this application.

[0038] Figure 12 This is a control block diagram for another implementation of the speed control loop. Detailed Implementation

[0039] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0040] In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0041] In existing technologies, during the low-speed implantation of dental implants, the motor may encounter sudden load changes. If the dental implant machine does not have a motor torque maintenance function, the motor will suddenly release torque under the control of the speed control loop, which will seriously affect the dentist's implantation experience and feel.

[0042] In order to achieve the motor torque maintenance function of a dental implant machine, this application provides a method for adjusting the motor torque of a dental implant machine.

[0043] As shown in the figure, in the dental implant machine, the motor 200 and the curved handpiece 300 are connected together through the transmission mechanism 400, and the output of the motor 200 is transmitted to the curved handpiece 300 by the transmission mechanism 400, that is, the motor 200 drives the curved handpiece 300 to move; in addition, the output torque of the motor 200 is controlled by the speed control loop in the main unit 100 connected to the motor 200.

[0044] It should be noted that the curved handpiece 300 is a device held by the doctor to drive the implant surgery instruments to complete the dental implant surgery. It is the same as existing technology and will not be described in detail here.

[0045] In practical applications, the speed control loop is used to adjust the output torque of the motor 200 by adjusting the duty cycle of the switching transistor of the inverter circuit 110 in the host 100, based on the motor speed deviation, i.e., the difference between the reference speed of the motor 200 and the feedback speed.

[0046] The reference speed is used to characterize the set speed of motor 200, that is, there is a mapping relationship between the reference speed and the set speed. The set speed of motor 200 is set by the user. However, in actual application, the set speed of motor 200 is indirectly set by the user. That is, the set speed of motor 200 is determined by the output speed of bending handpiece 300 set by the user and the speed ratio between bending handpiece 300 and motor 200.

[0047] For example, assuming the output speed of the bending handpiece 300 is set to 40 prm, and the ratio between the output speed of the bending handpiece 300 and the output speed of the motor 200 is 20:1, then the set speed of the motor 200 is 800 prm.

[0048] Feedback speed is used to characterize the output speed of motor 200, that is, there is a mapping relationship between feedback speed and output speed; in practical applications, the output speed is calculated based on the rotor position information collected by three Hall position sensors installed inside the motor.

[0049] The process of controlling the output torque of motor 200 according to the duty cycle is the same as the existing technology and will not be repeated here. The following is a detailed description of one implementation method of the speed control loop:

[0050] like Figure 1 As shown, the speed control loop includes a PI controller 10, a limiting module 20, a filtering module 30, and a duty cycle generation module 40.

[0051] The relationship between the output and input of the PI controller 10 is: outZ=Kp×up+ui=Kp×(Ref-Fbk)+ui, where outZ is the output of the PI controller 10, Kp is the proportional coefficient, up is the motor speed deviation, ui is the integral term output parameter, Ref is the reference speed, and Fbk is the feedback speed.

[0052] The relationship between the output and input of the limiting module 20 is: outX = IQsat(outZ, Umax, Umin), where outX is the output of the limiting module 20, IQsat is the limiting function, Umax is the maximum limiting value, and Umin is the minimum limiting value. In practical applications, Umax and Umin are set according to specific circumstances. By setting Umax and Umin, the smooth operation of the control can be ensured.

[0053] The relationship between the input and output of the filter module 30 is: outF=outX×K2 / (1-K 1), where outF is the output of the filter module 30, K1 is the first coefficient, and K2 is the second coefficient.

[0054] The relationship between the input and output of the duty cycle generation module 40 is: duty2 = duty1 + outF, where duty2 is the current duty cycle of the switching transistor of the inverter circuit in the host, and duty1 is the previous duty cycle of the switching transistor of the inverter circuit in the host.

[0055] As can be seen from the above, the specific control process of the speed control loop is as follows: when the output speed of the motor is less than the preset speed, that is, when the motor speed deviation up is greater than zero, the output outZ of the PI controller 10 is greater than zero, the output outX of the limiting module 20 is greater than zero, the output outF of the filter module 30 is greater than zero, and the current duty cycle duty2 of the switching transistor of the inverter circuit in the host is greater than zero, so the output torque of the motor is increased.

[0056] Therefore, it can be deduced that: if the output speed of the motor is lower, that is, the feedback speed Fbk is lower, the motor speed deviation up will be greater, the output outZ of PI controller 10 will be greater, the output outX of limiting module 20 will be greater, the output outF of filter module 30 will be greater, and the current duty cycle duty2 of the switching transistor of the inverter circuit in the host will be greater. Therefore, the speed control loop will increase the output torque of the motor more.

[0057] The specific process of this motor torque control method is as follows: Figure 2 As shown, the specific steps include:

[0058] S110, Determine if the motor has stopped.

[0059] If the motor stops, proceed to step S120; if the motor does not stop, end the motor torque control method.

[0060] In practical applications, when the motor stops, it indicates that the motor has encountered a sudden load change. Furthermore, as can be seen from the above explanation of the speed control loop, when the motor stops, the motor speed deviation is greater than zero, the output of the PI controller is greater than zero, and the duty cycle of the speed control loop output at this time, duty2, is greater than zero. Therefore, the output torque of the motor will be increased.

[0061] S120. Limit the adjustment of the duty cycle in the speed control loop to zero.

[0062] If the speed control loop is Figure 1 In the implementation shown, step S120 is specifically implemented by setting the maximum limiting value of the limiting module to zero.

[0063] Since the output of the PI controller in the speed control loop is greater than zero when the motor stops, limiting the adjustment of the duty cycle in the speed control loop to zero can limit the output of the PI controller to zero, thus keeping the duty cycle of the speed control loop output unchanged, and thus maintaining the output torque of the motor unchanged.

[0064] Since a motor stoppage indicates that the motor has encountered a sudden load change, the motor torque control method provided in this application can realize the motor torque maintenance function of the dental implant machine, thereby improving the dentist's implantation experience and feel.

[0065] In practical applications, when a motor encounters a sudden load change, the rotor may reverse. Because commutation cannot occur in time (i.e., the corresponding switching transistors cannot conduct), the stator cannot generate the necessary magnetic field to drive the rotor. Therefore, the motor may suddenly lose power, meaning it suddenly cannot output torque. To solve this problem, another embodiment of this application provides another implementation of a motor torque control method for a dental implant machine. The specific structure can be found in [reference needed]. Figure 3 (Taking only step S210 after step S120 as an example), this embodiment, based on the above embodiment, further includes the following steps after determining that the motor has stopped:

[0066] S210. Reset the commutation strategy in the host to: commutate the power supply voltage to the motor once every preset time interval.

[0067] It should be noted that, in this embodiment, the energizing phase sequence during commutation is the same as that in the prior art, and will not be described again here.

[0068] Preferably, the preset time is 40us. In practical applications, this may include, but is not limited to, this. No specific limitation is made here. It may be determined according to the specific circumstances, and all are within the protection scope of this application.

[0069] In practical applications, step S210 can be performed before, after, or simultaneously with step S120. No specific limitation is made here, and it can be determined according to the specific circumstances. All of these are within the protection scope of this application.

[0070] Because the power supply voltage of the motor is commutated once every preset time, the power supply voltage of the motor can be quickly commutated to the correct state, that is, the magnetic field generated by the stator can drive the rotor to rotate, that is, the motor restores its torque output capability. Therefore, the motor torque control method of the dental implant machine provided in this embodiment can avoid the occurrence of motor power loss, thereby further ensuring the realization of the motor torque maintenance function of the dental implant machine.

[0071] Typically, speed control loops include a PI (proportional integral) controller. However, in practical applications, the output of the PI controller often remains in its saturation region for extended periods, meaning the PI controller cannot effectively control the controlled object, thus impacting the performance of the speed control loop. To address this issue, this application provides another PI controller. The specific flow of the PI algorithm executed by this controller is as follows: Figure 4 As shown, the specific steps include:

[0072] S310. Determine whether the previous output of the PI controller is less than or equal to the minimum value of the preset limit range.

[0073] If the previous output of the PI controller is less than or equal to the minimum value of the preset limit range, then step S320 is executed; if the previous output of the PI controller is greater than the minimum value of the preset limit range, then step S330 is executed.

[0074] The preset limit range refers to the range of the PI controller's output when it is in the non-saturation region. That is, when the output of the PI controller is within the preset limit range, the controlled object will respond to the output of the PI controller.

[0075] The S320 PI controller only integrates motor speed deviations greater than zero in this instance.

[0076] In practical applications, when the previous output of the PI controller is less than or equal to the minimum value of the preset limit range, it indicates that the PI controller has exceeded the lower limit of the response range of the controlled object due to long-term integration of the motor speed deviation which is less than zero. This is recorded as the PI controller entering the lower saturation region.

[0077] Since the controlled object will not respond to the current output of the PI controller when the PI controller enters the lower saturation region, regardless of whether the motor speed deviation less than zero is integrated, the execution of step S320 at this time will not only not affect the control of the controlled object by the PI controller, but also make the output of the PI controller increase faster, thereby shortening the time that the PI controller stays in the lower saturation region.

[0078] Assuming the preset limit range is (-50, 100), the previous output of the PI controller is -100, and the current motor speed deviation is less than zero, if the existing PI algorithm is executed, i.e., the PI controller needs to integrate the motor speed deviation, the output of the PI controller will be less than -100, for example, -200. However, if the PI algorithm provided in this embodiment is executed, i.e., the PI controller does not integrate the motor speed deviation, the output of the PI controller will be greater than -200. Therefore, the time required to recover from a value greater than -200 to above -50 is less than the time required to recover from -200 to above -50, thereby shortening the time the PI controller stays in the lower saturation region through step S220.

[0079] S330: Determine whether the previous output of the PI controller is greater than or equal to the maximum value of the preset limit range.

[0080] If the previous output of the PI controller is greater than or equal to the maximum value of the preset limit range, then proceed to step S340; if the previous output of the PI controller is less than the maximum value of the preset limit range, then proceed to step S350.

[0081] The S340 PI controller only integrates motor speed deviations that are less than zero.

[0082] In practical applications, when the previous output of the PI controller is greater than or equal to the maximum value of the preset limit range, it indicates that the PI controller has exceeded the upper limit of the response range of the controlled object due to the long-term integration of the motor speed deviation greater than zero. This is recorded as the PI controller entering the upper saturation region.

[0083] Since the controlled object will not respond to the current output of the PI controller when the PI controller enters the upper saturation region, regardless of whether the motor speed deviation greater than zero is integrated, the execution of step S340 at this time will not only not affect the control of the controlled object by the PI controller, but also make the output of the PI controller decrease faster, thereby shortening the time that the PI controller stays in the upper saturation region.

[0084] Assuming the preset limit range is (-50, 100), the previous output of the PI controller is 200, and the current motor speed deviation is greater than zero, if the existing PI algorithm is executed, i.e., the PI controller needs to integrate the motor speed deviation, the output of the PI controller will be greater than 200, for example, 500. However, if the PI algorithm provided in this embodiment is executed, i.e., the PI controller does not integrate the motor speed deviation, the output of the PI controller will be less than 500. Therefore, the time required to recover from a value less than 500 to below 100 is greater than the time required to recover from 500 to below 100. Thus, step S240 can shorten the time the PI controller stays in the lower saturation region.

[0085] The S350 PI controller integrates the motor speed deviation in this test.

[0086] In summary, the PI algorithm provided in this embodiment can shorten the time that the PI controller stays in the saturation region, thereby avoiding the situation where the PI controller cannot control the controlled object to a certain extent, and thus reducing the impact on the performance of the speed control loop.

[0087] Another embodiment of this application provides a dental implant machine, the specific structure of which is as follows: Figure 5 As shown, it specifically includes: a main unit 100, a motor 200, and a bending handpiece 300; the main unit 100 specifically includes: an inverter circuit 110, a drive circuit 120, a controller 130, and three Hall position sensors (in... Figure 5 (The Hall sensor located inside the motor 200 is not shown in the image).

[0088] Three Hall position sensors are installed inside the motor 200 to detect the position of the rotor in the motor 200; the output terminals of the three Hall position sensors are respectively connected to the corresponding signal receiving terminals of the controller 130.

[0089] Motor 200 and bending handpiece 300 are connected via transmission mechanism 400 (in) Figure 5 (Only a simple diagram is shown in the figure, and the specific transmission method is not shown.) The power supply terminal of the motor 200 is connected to the AC side of the inverter circuit 110; the DC side of the inverter circuit 110 is connected to the power transmission terminal of the controller 130, and the power supply terminal of the controller 130 is connected to the grid power supply 500; under normal circumstances, the power supply of the grid power supply 500 is 220V.

[0090] The control terminal of the inverter circuit 110 is connected to the signal output terminal of the controller 130 through the drive circuit 120 and is controlled by the speed control loop in the controller 130. The specific contents of the speed control loop have been described above and will not be repeated here. The controller 130 is used to execute the motor torque control method of the dental implant machine provided in the above embodiment.

[0091] It should be noted that if the inverter circuit 110 adopts a three-phase two-level inverter topology, the drive circuit 120 consists of three drive chips, each corresponding to one phase bridge arm. In practical applications, the inverter circuit 110 and drive circuit 120 may include, but are not limited to, this implementation method, depending on the specific situation. No specific limitation is made here.

[0092] In practical applications, when the motor 200 encounters a sudden load change, the duty cycle of the speed control loop output may fluctuate excessively, causing the motor 200 to vibrate. To alleviate the vibration of the motor 200, another embodiment of this application provides another implementation of the host 100, the specific structure of which is as follows: Figure 6 (Unsimplified view in) Figure 6 As shown in the figure (not including the transmission mechanism and the bending handpiece), this embodiment, based on the above embodiment, also includes: three hardware low-pass filter circuits 140.

[0093] Each of the three Hall position sensors is connected to the controller through a corresponding hardware low-pass filter circuit 140.

[0094] In this embodiment, after the signal uploaded by the Hall position sensor passes through the hardware low-pass filter circuit 140, a portion of the high-frequency signal can be filtered out, making the signal uploaded by the Hall position sensor smoother. This reduces fluctuations in the duty cycle of the speed control loop output, thereby suppressing motor vibration caused by sudden load changes.

[0095] This embodiment also provides a specific implementation of the hardware low-pass filter circuit 140, the specific structure of which is as follows: Figure 7 (The diagram only shows one hardware low-pass filter circuit 140 as an example) as shown, specifically including: resistor branch 141 (in Figure 7 (The example shown uses only one resistor R) and capacitor branch 142 (in...) Figure 7 (This example uses only one capacitor, C).

[0096] One end of resistor branch 141 is connected to one end of capacitor branch 142, and the connection point serves as the output terminal of hardware low-pass filter circuit 140; the other end of resistor branch 141 serves as the input terminal of hardware low-pass filter circuit 140, and the other end of capacitor branch 142 is grounded to GND.

[0097] Another embodiment of this application provides another implementation of a dental implant machine, the specific structure of which can be found in [reference needed]. Figure 8 (only in) Figure 5 Based on the above embodiments, this embodiment further includes: a multi-functional foot pedal 600; in this embodiment, the main unit 100 also includes: a speed module 150.

[0098] The sampling terminal of the speed module 150 is connected to the multi-functional pedal 600, and the output terminal of the speed module 150 is connected to the sampling terminal of the controller 130. The controller 130 is used to determine the set speed of the motor 200 based on the real-time voltage of the multi-functional pedal 600 sampled by the speed module 150. Specifically, the higher the real-time voltage of the multi-functional pedal 600, the higher the set speed of the motor 200. However, it should be noted that the set speed of the motor 200 cannot exceed the specified maximum speed.

[0099] It should be noted that in practical applications, the multi-functional foot pedal 600 is equivalent to an adjustable resistor. The greater the pressure applied to the multi-functional foot pedal 600, the greater its resistance, and therefore the greater the voltage across its terminals. This is also the greater the real-time voltage of the multi-functional foot pedal 600 sampled by the speed module.

[0100] This embodiment provides another implementation of a dental implant machine, the specific structure of which can be found in [reference needed]. Figure 9 (only in) Figure 8 Based on the above embodiments, this embodiment further includes a peristaltic pump 700; the peristaltic pump 700 is controlled by the controller 130, the peristaltic pump 700 is used to provide power for water cooling of the surgical area during dental implantation, and the controller 130 can control the flow rate of the coolant through the peristaltic pump 700.

[0101] This embodiment provides yet another implementation of a dental implant machine, the specific structure of which can be found in [reference needed]. Figure 9 (only in) Figure 8 Based on the above embodiments, this implementation method further includes: an operation touch panel 800; the operation touch panel 800 is connected to the controller 130 in the host 100, and the operation touch panel can be used to operate or display the output speed of the bending machine 300, the speed ratio between the bending machine 300 and the motor 200, the maximum output torque of the bending machine 300, the rotation direction of the bending machine 300, the flow rate of the coolant, etc.

[0102] This embodiment provides another implementation of the host 100, the specific structure of which can be found in [reference needed]. Figure 10 (only in) Figure 9 Based on the above embodiments, this implementation also includes a current module 170 and a voltage module 180.

[0103] The controller 130 monitors the AC side voltage of the inverter circuit 110 through the voltage module 180; the controller 130 detects the AC side current of the inverter circuit 110 through the current module 170.

[0104] Another embodiment of this application provides a specific implementation of the controller 130, the specific structure of which can be found in [reference needed]. Figure 11 (only in) Figure 10 Based on the above (demonstration), it specifically includes: microprocessor 131, PWM logic processing module 132, and bus voltage generation module 133; wherein:

[0105] The microprocessor 131 is connected to the output terminals of the speed module 150, the voltage module 180, and the current module 170 via the ADC interface; the communication terminal of the microprocessor 131 is connected to the operation touch panel 800.

[0106] The power supply terminal of the microprocessor 131 is connected to the mains power supply 500. The microprocessor 131 is connected to the input terminal of the bus voltage generation module 133 through the GPIO port. The output terminal of the bus voltage generation module 133 is connected to the DC side of the inverter module.

[0107] Each signal receiving terminal of the microprocessor 131 is connected to the output terminal of the three Hall position sensors.

[0108] The signal output terminal of the microprocessor 131 is connected to the input terminal of the PWM logic processing module 132, and the output terminal of the PWM logic processing module 132 is connected to the control terminal of the inverter circuit 110.

[0109] The microprocessor 131 includes a motor torque regulation module. Figure 11 (Not shown in the image), the motor torque control module is used to execute the motor torque control method of the dental implant machine provided in the above embodiments.

[0110] The microprocessor 131 is used to determine the set speed of the motor 200 based on the real-time voltage of the multi-functional foot pedal 600 sampled by the speed module 150; to control the flow rate of the coolant through the peristaltic pump 700; to control the rotation direction of the motor 200; and to determine the position of the rotor based on the information uploaded by the three Hall sensors, thereby further determining the output speed of the motor 200.

[0111] It should be noted that in this embodiment, the microprocessor 131 is the same as in the prior art. In addition to the functions mentioned above, it also includes other functions, such as voltage space vector control, which will not be described in detail here.

[0112] The PWM logic processing module 132 includes a speed control loop. Specifically, the PWM logic processing module 132 is used to determine the duty cycle of the switching transistors in the inverter circuit 110 based on the output speed of the motor 200. In addition, the PWM logic processing module 132 is also used to determine the commutation time of each commutation based on the rotor position, and to commutate the power supply voltage of the motor at the corresponding commutation time according to the energizing phase sequence, thereby generating the conduction timing sequence of the switching transistors in the inverter circuit 110.

[0113] It should be noted that the speed control loop has been described in detail above and will not be repeated here.

[0114] In practical applications, with Figure 1 For example, Figure 12 As shown, a digital filter module is set before the input of the PI controller. Its output is equal to the weighted sum of the previous output of the digital filter module and the current input. Specifically, it can be expressed by the following formula: Yn=a*Xn+(1-a)*Yn-1, where: Xn is the current input of the digital filter module, Yn-1 is the previous output of the digital filter module, Yn is the current output of the digital filter module, and a is the filter coefficient. In practical applications, it is preferable to set a to 0.3.

[0115] By adding a digital filtering module, high-frequency signals can be further filtered out, thereby smoothing the signal uploaded by the Hall position sensor. This can further reduce fluctuations in the duty cycle of the speed control loop output, and thus further suppress motor vibration caused by sudden load changes.

[0116] The features described above in the disclosed embodiments can be substituted or combined with each other, enabling those skilled in the art to implement or use this application. The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention's technical solutions still fall within the protection scope of the present invention.

Claims

1. A method for controlling the motor torque of a dental implant machine, characterized in that, The output speed of the motor in the dental implant machine is controlled by the speed control loop of the main unit in the dental implant machine; The motor torque control method includes: Determine whether the motor has stopped; If the motor stops, the adjustment of the duty cycle in the speed control loop is limited to zero; The speed control loop includes a proportional-integral (PI) controller; the PI algorithm executed by the PI controller includes: Determine whether the previous output of the PI controller is less than or equal to the minimum value of the preset limit range; If the previous output is less than or equal to the minimum value of the preset limit range, then the PI controller will only integrate the motor speed deviation in the speed control loop that is greater than zero this time. If the previous output is greater than the minimum value of the preset limit range, then determine whether the previous output is greater than or equal to the maximum value of the preset limit range; If the previous output is greater than or equal to the maximum value of the preset limit range, the PI controller will only integrate the motor speed deviation that is less than zero this time.

2. The method for adjusting the motor torque of a dental implant machine according to claim 1, characterized in that, After determining that the motor has stopped, the process also includes: The commutation strategy in the host is reset to: the power supply voltage of the motor is commutated once every preset time interval.

3. The method for adjusting the motor torque of a dental implant machine according to claim 2, characterized in that, The preset time is 40us.

4. A dental implant machine, characterized in that, include: The host and motor; the host includes: an inverter circuit, a drive circuit, a controller, and three Hall position sensors; wherein: The three Hall position sensors are installed inside the motor to detect the position of the rotor in the motor; the output terminals of the three Hall position sensors are respectively connected to the corresponding signal receiving terminals of the controller. The AC side of the inverter circuit is connected to the motor; the control terminal of the inverter circuit is connected to the signal output terminal of the controller through the drive circuit, and is controlled by the speed control loop in the controller. The controller is used to perform the motor torque control method of the dental implant machine as described in any one of claims 1 to 3.

5. The dental implant machine according to claim 4, characterized in that, It also includes: a multi-functional foot pedal; the main unit further includes: a speed module; wherein: The controller is used to determine the set speed of the motor based on the real-time voltage of the multi-functional pedal sampled by the speed module.

6. The dental implant machine according to claim 4, characterized in that, The host also includes: three hardware low-pass filter circuits; wherein: The three Hall position sensors are each connected to the controller through a corresponding hardware low-pass filter circuit.

7. The dental implant machine according to claim 6, characterized in that, The hardware low-pass filter circuit includes: a resistor branch and a capacitor branch; wherein: One end of the resistor branch is connected to one end of the capacitor branch, and the connection point serves as the output terminal of the hardware low-pass filter circuit. The other end of the resistor branch serves as the input terminal of the hardware low-pass filter circuit, and the other end of the capacitor branch is grounded.

8. The dental implant machine according to any one of claims 4 to 7, characterized in that, The speed control loop further includes: a digital filtering module; wherein: The digital filtering module is positioned before the input of the PI controller in the speed control loop.

9. The dental implant machine according to claim 8, characterized in that, The output of the digital filtering module is equal to the weighted sum of the previous output and the current input of the digital filtering module.

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