Electric grinder device and control method

Abstract

The invention provides an electric grinder device and a control method, and relates to the technical field of electric tools. An electric grinder device comprises a main machine and an electric grinder body, a flexible shaft is arranged on the main machine, a transmission shaft is arranged on the electric grinder body, the transmission shaft is connected with the flexible shaft, and the electric grinder body further comprises a shell. The rotor is arranged on the transmission shaft in a sleeving manner; the electromagnetic coil is arranged on the shell; the circuit board is arranged in the shell, and the circuit board is electrically connected with the electromagnetic coil; wherein the host drives the transmission shaft to rotate through the flexible shaft, the transmission shaft drives the rotor to rotate, the electromagnetic coil generates induced voltage, and the electromagnetic coil supplies power to the circuit board. The invention further provides a control method of the electric grinder device. Relative movement of the rotor and the electromagnetic coil is set in the electric grinder body, voltage is induced and generated in the electromagnetic coil, and the voltage is supplied to the circuit board after rectification and voltage stabilization, so that the control module does not need to depend on a power supply circuit led out from a built-in battery or a host, the internal structure is effectively simplified, and the failure rate is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electric tools, and particularly relates to an electric grinder device and a control method. BACKGROUND

[0002] As a common handheld electric tool, the electric grinder device is widely used in the fields of metal processing, wood finishing, ceramic polishing and dental medical treatment. The traditional soft shaft electric grinder device is usually composed of a main machine and an electric grinder body, wherein the main machine is built-in with a motor, and the rotary power is transmitted to the grinding head of the electric grinder body through the soft shaft, so that the grinding or cutting operation on the workpiece is realized.

[0003] In the prior art, the start-stop control and the speed regulation function of the electric grinder device generally depend on the operation buttons or knobs at the main machine end, and the user needs to frequently go back and forth between the main machine and the work site during the operation process, which is extremely inconvenient to use. In order to improve the control experience, some products attempt to add a dedicated signal transmission cable between the main machine and the electric grinder body to realize the remote control function. However, such a scheme not only destroys the integrity of the overall appearance of the device, but also the additional wire is prone to breakage, poor contact and other problems under complex working conditions such as long-term bending and twisting, which seriously affects the reliability and service life of the device.

[0004] In addition, if an electronic control module is integrated on the electric grinder body, it must be provided with a stable power supply. The traditional method usually adopts a built-in battery or a power supply line drawn from the main machine, and the former is limited by the battery capacity and the replacement and maintenance cost, and the latter also faces the problems of complex wiring, easy loss and failure.

[0005] Therefore, there is an urgent need for an electric grinder device with simple structure, high reliability and without additional wiring or battery, which can realize self-powered intelligent control function while using the existing mechanical transmission structure, so as to improve the user experience and product stability. SUMMARY

[0006] The purpose of the present application is to solve the above-mentioned problems in the prior art, and a kind of electric grinder device and control method.

[0007] The purpose of the present application can be realized by the following technical scheme: an electric grinder device, comprising a main machine and an electric grinder body, a soft shaft is arranged on the main machine, a transmission shaft is arranged on the electric grinder body, the transmission shaft is connected with the soft shaft, and the electric grinder body further comprises:

[0008] a housing;

[0009] a rotor, the rotor is sleeved on the transmission shaft;

[0010] an electromagnetic coil, the electromagnetic coil is arranged on the housing;

[0011] A circuit board is arranged in the shell and electrically connected with the electromagnetic coil.

[0012] The host drives the transmission shaft to rotate through the soft shaft, the transmission shaft drives the rotor to rotate, the electromagnetic coil generates an induced voltage, and the electromagnetic coil supplies power to the circuit board.

[0013] As a further improvement of the application, the transmission shaft is provided with a mounting portion which protrudes radially from the transmission shaft, and the rotor is sleeved on the mounting portion.

[0014] As a further improvement of the application, the rotor can slide radially relative to the mounting portion.

[0015] As a further improvement of the application, the rotor is provided with a mounting hole, the mounting portion is arranged in the mounting hole, the length of the longest side of the cross section of the mounting hole is greater than the length of the longest side of the cross section of the mounting portion, and there is a gap between the mounting hole and the mounting portion.

[0016] As a further improvement of the application, the end of the transmission shaft connected with the soft shaft is provided with a shaft sleeve, the diameter of the shaft sleeve is greater than that of the transmission shaft, the shaft sleeve is provided with a connecting hole, and the soft shaft is inserted into the connecting hole.

[0017] As a further improvement of the application, the rotor is provided in a cross shape, four notches are uniformly distributed on the circumferential surface of the rotor, and the notches are composed of two mutually perpendicular surfaces.

[0018] As a further improvement of the application, the circuit board is provided with a start button and a speed control button, and the start button and the speed control button protrude from the outer surface of the shell.

[0019] As a further improvement of the application, the rotor bearing is provided with two rotor bearings arranged on the two axial sides of the rotor, respectively, the grinding head is connected with the transmission shaft through the shaft head.

[0020] The application also provides a control method of the electric grinder device, the electric grinder device comprising a host, a soft shaft, an electric grinder body, the electric grinder body being provided with a transmission shaft, a rotor, an electromagnetic coil and a circuit board, the control method comprising the following steps:

[0021] The soft shaft is driven by the host to drive the transmission shaft and the rotor to rotate at a high speed, so that the rotor generates an induced voltage in the electromagnetic coil;

[0022] The induced voltage is transmitted to the circuit board through a wire;

[0023] The rectification and voltage stabilization circuit and the power filter circuit on the circuit board are used to process the induced voltage and stabilize it to a preset working voltage range.

[0024] After stable power supply is obtained on the circuit board, the MCU on the circuit board is woken up.

[0025] The MCU detects the switch instruction and / or speed adjustment instruction input by the user.

[0026] The switch instruction and / or speed adjustment instruction are encoded and sent to the host through the wireless sending circuit on the circuit board to realize remote switch control and / or speed adjustment of the electric grinder.

[0027] As a further improvement of the application, the MCU is in a low-power sleep state when no valid power supply is detected or no user operation is performed; when the voltage output by the rectification and voltage stabilization circuit reaches a preset threshold, the MCU is automatically woken up from the sleep state and starts to monitor the switch instruction and speed adjustment instruction; the wireless sending circuit uses one of Bluetooth BLE, ZigBee, Sub-1GHz radio frequency, or 2.4GHz proprietary wireless protocol to send the encoded instruction to the receiving module of the host in the form of a wireless signal.

[0028] Based on the above technical solution, the application can at least produce the following technical effects:

[0029] 1. By arranging the relative motion structure of the rotor and the electromagnetic coil inside the electric grinder body, the rotor is driven to rotate at high speed by the flexible shaft, and a voltage is induced in the electromagnetic coil, which is used to supply power to the circuit board after rectification and voltage stabilization. This ingenious design converts mechanical kinetic energy into electrical energy, so that the control module does not need to rely on the built-in battery or the power supply line from the host, effectively simplifying the internal structure and reducing the failure rate.

[0030] 2. After the circuit board obtains stable power supply, the MCU can be automatically woken up, the user's operation on the start button or speed control button is detected in real time, and the instruction is encoded and sent to the host through a wireless manner to realize remote start-stop and stepless speed regulation of the electric grinder. The user can complete all control operations directly at the grinding work position, avoiding frequent trips to the host end, significantly improving work efficiency and use safety.

[0031] 3. This scheme eliminates the additional wires for signal transmission or power supply in traditional electric grinders, and only relies on the flexible shaft to transmit power and simultaneously realize energy harvesting, which not only reduces the internal space occupation, but also avoids problems such as breakage and poor contact caused by long-term bending of multiple cables. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort based on these drawings.

[0033] Figure 1 is a sectional view of the electric grinder device of the present application.

[0034] Figure 2 is a schematic view of the electric grinder body in the electric grinder device of the present application.

[0035] Figure 3 is a schematic view of the transmission shaft and rotor in the electric grinder device of the present application.

[0036] Figure 4 is a circuit system block diagram of the electric grinder device of the present application.

[0037] Figure 5 is a flow chart of the control method of the electric grinder device of the present application.

[0038] In the figure, 100, main machine; 200, flexible shaft; 300, electric grinder body; 310, transmission shaft; 311, mounting portion; 312, shaft sleeve; 320, housing; 330, rotor; 331, notch; 332, mounting hole; 340, electromagnetic coil; 350, circuit board; 351, start button; 352, speed control button; 360, rotor bearing; 370, grinder head; 380, shaft head. DETAILED DESCRIPTION

[0039] It should be noted that all the direction indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the direction indications will also change accordingly. In addition, the descriptions such as "first", "second", "one", etc. in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited. In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixation", etc. should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium; can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the scope of protection claimed by the present application.

[0040] The following is a specific embodiment of the present application, and the accompanying drawings are combined Figures 1-5 The technical solutions of the present application are further described, but the present application is not limited to the following embodiments.

[0041] The electric grinder device described in the present application mainly includes three parts of a main machine 100, a flexible shaft 200 and an electric grinder body 300. The main machine 100 is internally provided with a driving motor for providing rotary power; one end of the flexible shaft 200 is connected with the output shaft of the main machine 100, and the other end is connected with a transmission shaft 310 in the electric grinder body 300, so as to transmit the rotary motion generated by the main machine 100 to the electric grinder body 300, and drive the grinding head 370 to perform grinding work. Unlike the traditional electric grinder device, the present application ingeniously integrates an energy collection and wireless control module in the electric grinder body 300, so that it can realize remote start and stop and speed regulation function of the main machine 100 without external power supply or additional signal cable.

[0042] The electric grinder body 300 is composed of a shell 320 made of high-strength engineering plastic or metal material, which has good mechanical strength and heat dissipation performance. The shell 320 is provided with a transmission shaft 310, a rotor 330, an electromagnetic coil 340, a circuit board 350, a rotor bearing 360, a shaft head 380, a grinding head 370 and other key components. One end of the transmission shaft 310 is connected with the flexible shaft 200 through a shaft sleeve 312. The diameter of the shaft sleeve 312 is larger than that of the transmission shaft 310, and a connecting hole matched with the flexible shaft 200 is formed in the shaft sleeve 312. After the flexible shaft 200 is inserted into the connecting hole, reliable connection is achieved through fasteners or interference fit, ensuring efficient power transmission. The other end of the transmission shaft 310 is connected with the grinding head 370 through the shaft head 380. The grinding head 370 can be replaced with accessories such as grinding wheel, drill bit and polishing wheel according to different application scenarios.

[0043] A radially protruding mounting portion 311 is arranged at the position of the transmission shaft 310 close to the connecting end of the flexible shaft 200. The cross section of the mounting portion 311 can be square, rectangular or polygonal to enhance the torque transmission capacity between the mounting portion 311 and the rotor 330. The rotor 330 is sleeved on the mounting portion 311, and an installation hole 332 matched with the shape of the mounting portion 311 is arranged in the rotor 330. It is worth noting that the length of the longest side of the cross section of the installation hole 332 is slightly larger than that of the corresponding side of the mounting portion 311, and a small gap is reserved therebetween, so that the rotor 330 can slide in the radial direction of the mounting portion 311. This design not only helps to relieve stress concentration caused by manufacturing tolerance or assembly deviation, but also absorbs part of the vibration during high-speed rotation, improving the running stability.

[0044] In the embodiment, the rotor 330 is arranged as a magnetic steel, and the rotor 330 has a cross structure. Four notches 331 are uniformly distributed on the outer circumferential surface of the rotor 330 in the circumferential direction. Each notch 331 is composed of two mutually perpendicular planes, forming a geometric feature similar to an "L" shape. This structure not only helps to reduce the mass and moment of inertia of the rotor 330, but more importantly, when the rotor 330 rotates at high speed, the edge profile of the rotor 330 can periodically cut the magnetic induction lines of the electromagnetic coil 340, thereby generating an alternating induced electromotive force in the electromagnetic coil 340. The electromagnetic coil 340 is fixedly installed on the inner wall of the shell 320 and surrounds the outer periphery of the rotor 330. The number of turns, wire diameter and core material of the winding of the electromagnetic coil 340 are optimized to obtain sufficient and stable induced voltage in the typical working speed range.

[0045] The generated induction voltage is led out through a wire and connected to a circuit board 350 arranged inside the housing 320. The circuit board 350 is integrated with a rectifier and voltage stabilizing circuit, a power filter circuit, a microcontroller unit (MCU), a wireless transmission circuit, and user interaction elements (such as a start button 351 and a speed control button 352). The rectifier and voltage stabilizing circuit is usually composed of a bridge rectifier and a DC-DC step-down module, which is used to convert alternating current induction voltage into direct current and stabilize the output to a preset working voltage range; the power filter circuit includes capacitors, inductors, and other elements, which are used to suppress voltage ripple and electromagnetic interference, ensuring the stable operation of subsequent electronic components.

[0046] When the host 100 is started and drives the soft shaft 200 to rotate, the transmission shaft 310 rotates at high speed, thereby driving the rotor 330 to rotate synchronously inside the electromagnetic coil 340. At this time, the electromagnetic coil 340 starts to continuously output an induction voltage. In the initial stage, due to the low speed, the induction voltage may not be sufficient to activate the circuit system, and the MCU is in a low-power sleep state to save energy. As the speed increases, the voltage output by the rectifier and voltage stabilizing circuit gradually rises, and once it reaches a preset threshold (such as 2.8V), the MCU is automatically awakened from the sleep state. After being awakened, the MCU immediately starts to scan the user input signal to detect whether the start button 351 or the speed control button 352 is pressed.

[0047] The start button 351 and the speed control button 352 are both protruding from the outer surface of the housing 320, which is convenient for single-handed operation by the user when holding the electric grinder body 300 to work. When the user presses the start button 351, the MCU recognizes the switch command and encodes it into a specific data frame; if the speed control button 352 is also operated, the MCU can obtain the corresponding speed level information. Subsequently, the MCU sends the above-mentioned command to the host 100 in the form of a wireless signal through the wireless transmission circuit. The wireless transmission circuit can use one of the low-power Bluetooth (BLE), ZigBee, Sub-1GHz radio frequency, or 2.4GHz proprietary wireless protocol, and the specific choice depends on the communication distance, power consumption requirements, and anti-interference performance. The host 100 end is provided with a corresponding wireless receiving module, which receives the command and is parsed and executed by the host chip to perform corresponding operations, such as starting the motor and adjusting the PWM duty cycle to change the output speed.

[0048] It is worth emphasizing that the entire control process completely relies on the induction power generated by the relative motion of the rotor 330 and the electromagnetic coil 340, without the need for an internal battery or any additional power supply or communication cables between the host 100 and the electric grinder body 300. This not only greatly simplifies the product structure, reduces assembly difficulty and material cost, but also fundamentally avoids common faults such as cable breakage and poor contact caused by long-term bending and pulling, significantly improving the reliability and service life of the equipment.

[0049] In addition, two rotor bearings 360 are arranged on both sides of the rotor 330 respectively, for supporting the transmission shaft 310 and ensuring the rotation accuracy thereof. The bearings adopt high-precision micro ball bearings or oil-containing copper sleeves, and have the characteristics of low friction, wear resistance and high-speed operation. The shaft head 380 and the transmission shaft 310 can be connected with the grinding head 370 through threads, clamping springs or quick-change clamps, so as to facilitate users to quickly replace different types of processing accessories.

[0050] In actual use, the user only needs to connect the electric grinder device to the power supply of the main machine 100, and after turning on the switch of the main machine 100, the grinding head 370 on the electric grinder body 300 starts to rotate. The user holds the electric grinder body 300 close to the area to be processed for processing, and presses the speed control button 352 on the shell 320 to remotely control the rotation speed of the main machine 100. After the processing is completed, the start button 351 is pressed, and the main machine 100 stops rotating. The whole operation process is smooth and natural, without the need to look away from the work surface or interrupt the work to operate the main machine 100, which greatly improves the human-machine interaction experience and work efficiency.

[0051] In summary, the application introduces electromagnetic induction power generation and wireless communication technology on the basis of the traditional electric grinder structure, and constructs a new type of electric grinder device with self-power supply, intelligence and high reliability. The core innovation is that the power transmitted by the flexible shaft 200 is used to synchronously drive the rotor 330 to rotate, to generate electric energy in the fixed coil and to supply power to the local control circuit; and the user's instruction is returned to the main machine 100 through a wireless manner, to realize closed-loop control. The scheme not only solves the pain points of the existing products, such as inconvenient operation, complex wiring and easy failure, but also provides a feasible technical path for the future development of battery-free, modular and intelligent electric tools.

[0052] The specific embodiments described herein are merely illustrative of the spirit of the application. Those skilled in the art of the present application can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, without deviating from the spirit of the application or exceeding the scope defined by the appended claims.

Claims

1. A control method for an electric grinder device, characterized in that, The electric grinder device comprises a main machine (100), a soft shaft (200), and an electric grinder body (300) provided with a transmission shaft (310), a rotor (330), an electromagnetic coil (340), and a circuit board (350); and the control method comprises the following steps: The soft shaft (200) is driven by the main machine (100) to drive the transmission shaft (310) and the rotor (330) to rotate at a high speed, so that the rotor (330) generates an induced voltage in the electromagnetic coil (340); The induced voltage is transmitted to the circuit board (350) through a wire; The induced voltage is processed by a rectification and voltage stabilization circuit and a power filter circuit on the circuit board (350) to stabilize it to a preset working voltage range; After stable power supply is obtained on the circuit board (350), an MCU on the circuit board (350) is woken up; The MCU detects switch instructions and / or speed adjustment instructions input by a user; The switch instructions and / or speed adjustment instructions are encoded and sent to the main machine (100) through a wireless sending circuit on the circuit board (350) to realize remote switch control and / or speed adjustment of the electric grinder device.

2. The method of claim 1, wherein, When no valid power supply or user operation is detected, the MCU is in a low-power sleep state; when the voltage output by the rectification and voltage stabilization circuit reaches a preset threshold, the MCU is automatically woken up from the sleep state and starts to monitor the switch instructions and speed adjustment instructions; the wireless sending circuit sends the encoded instructions to a receiving module of the main machine (100) in the form of wireless signals by using one of Bluetooth BLE, ZigBee, Sub-1GHz radio frequency, or 2.4GHz proprietary wireless protocols.

3. An electric grinder device, comprising a main machine (100) and an electric grinder body (300), a flexible shaft (200) is arranged on the main machine (100), a transmission shaft (310) is arranged on the electric grinder body (300), and the transmission shaft (310) is connected with the flexible shaft (200), characterized in that, The electric grinder body (300) further comprises: a housing (320); a rotor (330) sleeved on the transmission shaft (310); an electromagnetic coil (340) arranged on the housing (320); a circuit board (350) arranged in the housing (320) and electrically connected with the electromagnetic coil (340); The main machine (100) drives the transmission shaft (310) to rotate through the soft shaft (200), the transmission shaft (310) drives the rotor (330) to rotate, the electromagnetic coil (340) generates an induced voltage, and the electromagnetic coil (340) supplies power to the circuit board (350).

4. The electrical grinding device of claim 3, wherein, The transmission shaft (310) is provided with a mounting portion (311) radially protruding from the transmission shaft (310), and the rotor (330) is sleeved on the mounting portion (311).

5. The electrical grinding device of claim 4, wherein, The rotor (330) can slide radially relative to the mounting portion (311).

6. The electrical grinding device of claim 4, wherein, The rotor (330) is provided with a mounting hole (332), the mounting portion (311) is arranged in the mounting hole (332), the length of the longest side of the cross section of the mounting hole (332) is greater than the length of the longest side of the cross section of the mounting portion (311), and a gap exists between the mounting hole (332) and the mounting portion (311).

7. The electrical grinding device of claim 3, wherein, One end of the transmission shaft (310) connected with the soft shaft (200) is provided with a shaft sleeve (312), the diameter of the shaft sleeve (312) is greater than that of the transmission shaft (310), the shaft sleeve (312) is provided with a connecting hole, and the soft shaft (200) is inserted into the connecting hole.

8. The electrical grinding device of claim 3, wherein, The rotor (330) is provided in a cross shape, four notches (331) are uniformly distributed on the outer circumferential surface of the rotor (330) in the circumferential direction, and the notch (331) is composed of two mutually perpendicular surfaces.

9. The electrical grinding device of claim 3, wherein, The circuit board (350) is provided with a start button (351) and a speed control button (352), and the start button (351) and the speed control button (352) protrude from the outer surface of the shell (320).

10. The electrical grinding device of claim 3, wherein, Further comprising a rotor bearing (360), a grinding head (370) and a shaft head (380), the rotor bearing (360) is provided with two and arranged on both sides of the rotor (330) in the axial direction, the grinding head (370) is connected with the transmission shaft (310) through the shaft head (380).

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