An energy-saving sonic motor for an electric toothbrush

Abstract

The present invention relates to the technical field of sonic motors, and in particular to an energy-saving sonic motor for an electric toothbrush. It comprises a motor housing, the motor housing is rotatably connected to a rotating shaft, a stator core is installed in the motor housing, a rotor is installed on the rotating shaft, the motor housing is fixedly connected to a rear housing, the coil lead on the stator core in the motor housing is connected to the mainboard wire of the electric toothbrush, a fixing ring is fixed in the rear housing, the fixing ring in the rear housing is rotatably connected to a connecting piece, the connecting piece is fixedly connected to a spline sleeve, a rotor spring is fixedly connected between the connecting piece and the rear housing, and a pressure sensor is fixedly connected to the rotor spring. The present invention installs a pressure sensor on the rotor spring so that the pressure sensor senses two vibration changes at the same time, and the pressure sensor accurately feeds back the sensed vibration changes to the mainboard of the electric toothbrush, and then realizes accurate control of the vibration frequency of the rotor.

Description

Technical Field

[0001] This invention relates to the field of acoustic motor technology, and more particularly to an energy-saving acoustic motor for electric toothbrushes. Background Technology

[0002] As people's living standards improve, they are paying more and more attention to oral health. Due to the advantages of sonic electric toothbrushes, such as strong cleaning ability and convenience, sonic electric toothbrushes have gradually come into people's view. As the popularity of sonic electric toothbrushes increases, the technology of sonic electric toothbrushes is also becoming more and more mature. Now people's requirements for sonic motors are trending towards motor stability and the versatility of electric toothbrush functions.

[0003] To adjust the vibration frequency of the brush head based on the pressure between the brush head and teeth during brushing, existing sonic electric toothbrushes mount a pressure sensor on the output shaft of the sonic motor. This sensor detects the pressure of the brush head on the teeth and controls the friction between them to prevent excessive tooth wear. However, when the pressure sensor is mounted on the output shaft, it only detects vibration changes in one direction. Vibration changes perpendicular to the output shaft are not detected, leading to errors in the pressure sensed. This results in inaccurate control of the rotor's vibration frequency, preventing the brush head from precisely adjusting the vibration frequency based on the pressure between it and the teeth. Consequently, the friction between the brush head and teeth is not effectively controlled, resulting in a poorer user experience. Summary of the Invention

[0004] In order to overcome the shortcomings of existing sonic electric toothbrushes that cannot adjust the vibration frequency of the sonic motor rotor by accurately detecting the pressure between the brush head and the teeth, the present invention provides an energy-saving sonic motor for electric toothbrushes.

[0005] The technical solution is as follows: An energy-saving sonic motor for an electric toothbrush includes a motor housing, a rotating shaft rotatably connected to the motor housing, a stator core installed inside the motor housing, a rotor installed on the rotating shaft, a rear shell fixedly connected to the motor housing, coil leads on the stator core inside the motor housing connected to the mainboard wires of the electric toothbrush, a retaining ring fixedly connected inside the rear shell, a connector rotatably connected to the retaining ring inside the rear shell, a spline sleeve fixedly connected to the side of the connector near the rotating shaft, a spline on the end of the rotating shaft near the spline sleeve, the rotating shaft engaging with the spline sleeve via the spline on the spindle, a rotating bullet fixedly connected between the side of the connector away from the spline sleeve and the rear shell, a pressure sensor fixedly connected to the rotating bullet, a lead of the pressure sensor passing through the rear shell, the lead of the pressure sensor connected to the mainboard wires of the electric toothbrush, and the pressure sensor used to monitor the vibration changes of the rotating bullet.

[0006] As a further preferred embodiment, the rotating bullet is made of stainless steel to ensure that the rotating shaft generates stable vibration.

[0007] As a further preferred embodiment, it also includes a rotating plate rotatably connected to the spline sleeve. The rotating plate and the connecting piece are in close contact. Symmetrical fixed posts are fixedly connected to the side of the rotating plate near the rotating shaft. Guide frames are slidably connected to the fixed posts. Symmetrical fixed tubes are fixedly connected inside the rear shell. Both ends of the fixed tubes are fixedly connected to sealing caps. Sliding posts are slidably connected between adjacent sealing caps. The sliding posts are located inside the fixed tubes. Pistons are fixedly connected to the sliding posts. The pistons are sealed and slidably connected to adjacent fixed tubes. Air with an initial pressure greater than atmospheric pressure is injected between the pistons and adjacent sealing caps. Both ends of the sliding posts are fixedly connected to adjacent guide frames via L-plates.

[0008] As a further preferred embodiment, the fixing post is fixedly connected to a mounting plate, the mounting plate of the fixing post is slidably engaged with the adjacent guide frame, and ball bearings for reducing friction are installed between the fixing post and the adjacent guide frame.

[0009] As a further preferred embodiment, a sealing ring is installed on the outer side of the piston to maintain the same air pressure on both sides of the piston.

[0010] As a further preferred embodiment, a seal is installed between the fixed tube and the adjacent sealing cap, and a seal is installed between the sealing cap and the adjacent sliding column to prevent air leakage from both sides of the piston.

[0011] As a further preferred embodiment, it also includes four first neodymium magnets, which are respectively fixed to both sides of the symmetrical pistons. A second neodymium magnet is fixed to the side of the sealing cap near the adjacent piston, and the opposite ends of the second neodymium magnet and the adjacent first neodymium magnet have the same magnetic poles.

[0012] As a further preferred embodiment, both the first neodymium magnet and the second neodymium magnet are configured as rings, and neither the first neodymium magnet nor the second neodymium magnet contacts the adjacent sliding post, thereby reducing the wear of the sliding post.

[0013] As a further preferred embodiment, the device also includes a micro motor fixedly connected to the rear housing and electrically connected to the mainboard of the electric toothbrush. A lead screw is rotatably connected to the rear housing, and the output shaft of the micro motor is fixedly connected to the lead screw. The connector has symmetrical through holes, and limit posts are slidably connected within these through holes. A rotating ring is fixedly connected to the symmetrical limit posts. The rotating plate has symmetrical blind holes, and the limit posts are matched with adjacent blind holes on the rotating plate. A connecting ring is rotatably connected to the side of the rotating ring away from the spline sleeve, and the connecting ring is threadedly connected to the lead screw via a mounting plate.

[0014] As a further preferred embodiment, the end of the limiting post near the rotating plate is provided with an inclined annular surface, which facilitates the insertion of the limiting post into the adjacent blind hole of the rotating plate.

[0015] In summary, the beneficial effects of this invention are as follows: By installing a pressure sensor on the rotor, the pressure sensor simultaneously senses two vibration changes. The pressure sensor accurately feeds back the sensed vibration changes to the mainboard of the electric toothbrush, thereby achieving precise control of the rotor's vibration frequency. This not only improves the user's brushing experience but also saves the electric toothbrush's power. Furthermore, this invention utilizes the piston's up-and-down compression of air and the magnetic interaction between the second neodymium magnet and the adjacent first neodymium magnet to provide partial reset force to the rotor, thereby mitigating the problem of reduced rotor vibration frequency caused by decreased rotor elasticity and mechanical strength. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0017] Figure 2 This is a cross-sectional perspective view of the rear shell of the present invention.

[0018] Figure 3 This is a three-dimensional structural diagram of the connector and rotating bullet piece of the present invention;

[0019] Figure 4 This is a three-dimensional structural diagram of the rotating plate and fixed tube components of the present invention;

[0020] Figure 5 This is a cross-sectional perspective view of the connector and rotating plate of the present invention.

[0021] Figure 6 This is a cross-sectional perspective view of the fixing tube and sealing cap of the present invention.

[0022] The following are the labels in the diagram: 1. Motor housing, 2. Rotating shaft, 3. Rear housing, 4. Connecting piece, 5. Spline sleeve, 6. Rotating bullet piece, 7. Pressure sensor, 8. Rotating plate, 9. Fixed column, 10. Guide frame, 11. Fixed tube, 12. Sealing cover, 13. Sliding column, 14. Piston, 15. First neodymium magnet, 16. Second neodymium magnet, 17. Micro motor, 18. Lead screw, 19. Limiting column, 20. Rotating ring, 21. Connecting ring. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] With the continuous advancement of sonic electric toothbrush technology, research has revealed that existing electric toothbrushes use pressure sensors to detect the pressure between the brush head and teeth. However, these sensors are typically mounted on the output shaft of the sonic motor. Mounting the sensor on the output shaft only detects vibration changes in a single direction; it cannot sense vibration changes in the vertical direction. This results in the pressure sensor not being able to effectively and accurately sense the pressure between the brush head and teeth, thus hindering the precise adjustment of the sonic motor's vibration frequency. The following implementation method addresses these issues.

[0025] Example 1: An energy-saving sonic motor for electric toothbrushes, such as... Figures 1-3As shown, the device includes a motor housing 1, a rotating shaft 2 rotatably connected to the motor housing 1, the rotating shaft 2 passing through the left side of the motor housing 1, and a bearing installed between the motor housing 1 and the rotating shaft 2. A stator core is installed inside the motor housing 1, and a rotor is installed on the rotating shaft 2. A rear housing 3 is fixedly connected to the right side of the motor housing 1. A coil is wound on the stator core, and the coil leads pass through the rear housing 3. When an alternating voltage is applied to the coil on the stator core, the coil generates an alternating magnetic field, which, in conjunction with the rotor's magnetic force, causes the rotor to reciprocate at high frequency. The coil leads on the stator core inside the motor housing 1 are connected to the mainboard wires of the electric toothbrush. A retaining ring is fixedly connected inside the rear housing 3, and a connector 4 is rotatably connected to the retaining ring inside the rear housing 3. The connector 4 is located on the right side of the rotating shaft 2. A spline sleeve 5 is fixedly connected to the left side, and the right end of the rotating shaft 2 is set as a spline. The rotating shaft 2 engages with the spline sleeve 5 through the spline on it. During the high-frequency reciprocating rotation of the rotor, the rotating shaft 2 drives the spline sleeve 5 and the connecting piece 4 to reciprocate synchronously through the spline. A rotating bullet 6 is fixedly connected between the right side of the connecting piece 4 and the rear shell 3. The rotating bullet 6 is made of stainless steel to ensure that the rotating shaft 2 generates stable vibration. A pressure sensor 7 is fixedly connected to the rotating bullet 6. The pressure sensor 7 is an existing working element. The lead of the pressure sensor 7 passes through the rear shell 3 and is connected to the wire of the electric toothbrush motherboard. The pressure sensor 7 is used to monitor the vibration change of the rotating bullet 6, and then adjust the frequency of the input alternating current to control the frequency of the rotor's reciprocating rotation.

[0026] After the user starts the electric toothbrush, the rotor begins to rotate at a high frequency. The rotor drives the rotating shaft 2 to rotate synchronously. The rotating shaft 2 drives the spline sleeve 5 and the connecting piece 4 to rotate synchronously via the spline. The connecting piece 4 rotates back and forth along the fixed ring. During the reciprocating motion, the connecting piece 4 causes the left end of the rotating bullet piece 6 to twist. The rotating bullet piece 6 generates a reaction force, causing the rotor to spring back. After the frequency of the input alternating voltage reaches a certain value, the rotating bullet piece 6 resonates, thereby increasing the output force of the rotating shaft 2. The pressure sensor 7 monitors the changes in the vibration of the rotating bullet piece 6 in real time and transmits the detection signal to the main board of the electric toothbrush. The pressure sensor 7 senses the vibration changes of the rotor immediately. There is no external force acting on the rotating shaft 2. When the output shaft is in operation, the rotating bullet 6 mainly vibrates in the front-to-back direction. When the rotating shaft 2 is subjected to external pressure, the rotating bullet 6 generates a reverse force. At this time, the rotating bullet 6 exhibits both front-to-back and vertical vibration changes. The pressure sensor 7 detects both vibration changes simultaneously and accurately feeds the detected vibration changes back to the main board of the electric toothbrush. This allows for precise control of the rotor's vibration frequency, improving the user's brushing experience and saving the electric toothbrush's power. After the toothbrush is turned off, the rotor stops rotating. Under the elastic force of the rotating bullet 6, the connecting piece 4 and its spline sleeve 5 are reset. Subsequently, the spline sleeve 5 drives the rotating shaft 2 and its rotor to reset.

[0027] Example 2: Based on Example 1, as follows Figures 3-6As shown, it also includes a rotating plate 8, which is rotatably connected to the spline sleeve 5. The right side of the rotating plate 8 is in contact with the left side of the connector 4. Two symmetrical fixed posts 9 are fixedly connected to the left side of the rotating plate 8. A guide frame 10 is slidably connected to the fixed posts 9. The guide frame 10 is rectangular. Two symmetrical fixed tubes 11 are fixedly connected inside the rear shell 3. Both ends of the fixed tubes 11 are fixedly connected to sealing caps 12. A sliding post 13 is slidably connected between adjacent sealing caps 12. The sliding post 13 is located inside the fixed tube 11. The central axis of the sliding post 13 coincides with the central axis of the fixed tube 11. A piston 14 is fixedly connected to the sliding post 13. The piston 14 is sealed and slidably connected inside the adjacent fixed tube 11. A sealing ring is installed on the outside of the piston 14 to raise the piston 14 and the adjacent fixed tube. The inner wall of 11 is sealed to maintain the same air pressure on both sides of piston 14. Air with an initial pressure greater than atmospheric pressure is injected between piston 14 and adjacent sealing cover 12. Both ends of sliding column 13 are fixed to adjacent guide frame 10 through L-plates. Mounting plate is fixed to fixed column 9. Mounting plate of fixed column 9 slides with adjacent guide frame 10. Ball bearings are installed between fixed column 9 and adjacent guide frame 10 to reduce friction and reduce wear between fixed column 9 and adjacent guide frame 10. Seals are installed between fixed tube 11 and adjacent sealing cover 12, and seals are installed between sealing cover 12 and adjacent sliding column 13 to prevent air leakage from both sides of piston 14, which would reduce the air pressure between piston 14 and adjacent sealing cover 12.

[0028] like Figure 6 As shown, it also includes four first neodymium magnets 15, which are fixed to both sides of the two pistons 14 respectively. Second neodymium magnets 16 are fixed to the opposite sides of the two adjacent sealing caps 12. The opposite ends of the second neodymium magnets 16 and the adjacent first neodymium magnets 15 have the same magnetic poles. The first neodymium magnets 15 and the second neodymium magnets 16 are both set as rings, and neither the first neodymium magnets 15 nor the second neodymium magnets 16 contact the adjacent sliding column 13, thereby reducing the wear of the sliding column 13 and improving the sealing performance between the sliding column 13 and the two adjacent sealing caps 12.

[0029] like Figure 3 and Figure 5As shown, it also includes a micro motor 17, which is fixedly connected to the rear shell 3 and electrically connected to the electric toothbrush mainboard. The micro motor 17 is an existing electric device, and its specific structure is not shown in the attached drawings. A lead screw 18 is rotatably connected to the rear shell 3, and the output shaft of the micro motor 17 is fixedly connected to the lead screw 18. The connecting piece 4 is provided with two symmetrical through holes, and limit posts 19 are slidably connected in the through holes of the connecting piece 4. The two limit posts 19 are jointly fixedly connected to a rotating ring 20. The rotating plate 8 is provided with a pair of The two blind holes are respectively, and the limiting post 19 is matched with the blind hole adjacent to the rotating plate 8. After the limiting post 19 is inserted into the blind hole adjacent to the rotating plate 8, the rotating plate 8 will rotate synchronously with the connecting piece 4 at high frequency. The right side of the rotating ring 20 is rotatably connected to the connecting ring 21. The connecting ring 21 is threadedly connected to the lead screw 18 through the mounting plate. When the lead screw 18 rotates, the lead screw 18 drives the connecting ring 21 to move to the left. The left end of the limiting post 19 is provided with an inclined ring surface, which makes it easy for the limiting post 19 to be inserted into the blind hole adjacent to the rotating plate 8.

[0030] As the electric toothbrush is used for a longer period of time, the elasticity and mechanical strength of the rotor shrapnel 6 decrease, resulting in a reduction in the rotor's vibration efficiency. When the pressure sensor 7 detects that the vibration frequency of the rotor shrapnel 6 has decreased to a specified value, the mainboard of the electric toothbrush activates the micro motor 17. The output shaft of the micro motor 17 drives the lead screw 18 to rotate. The lead screw 18 drives the connecting ring 21 to move to the left via a thread. The connecting ring 21 drives the rotating ring 20 to move to the left simultaneously. The rotating ring 20 drives the two limiting posts 19 to slide to the left. The limiting posts 19 slide along the adjacent connecting piece 4. As the through hole slides to the left, the connecting piece 4 reciprocates along the fixing piece during the movement of the limiting post 19 to the left. Driven by the connecting piece 4, the two limiting posts 19 drive the rotating ring 20 to rotate along the connecting ring 21 until the two limiting posts 19 are respectively inserted into the adjacent blind holes of the rotating plate 8. Then, under the limiting action of the two limiting posts 19, the rotating plate 8 reciprocates synchronously with the connecting piece 4. After the limiting post 19 is fully inserted into the blind hole of the rotating plate 8, the main board of the electric toothbrush shuts down the micro motor 17, and the main shaft of the micro motor 17 stops rotating.

[0031] During the reciprocating rotation of the rotating plate 8 with the connecting piece 4, the rotating plate 8 drives the two fixed posts 9 to move synchronously. At the same time, the fixed posts 9 drive the adjacent guide frames 10 to move up and down reciprocally. The fixed posts 9 slide back and forth within the adjacent guide frames 10. Taking the reciprocating movement of the front guide frame 10 as an example, the guide frame 10 drives the middle sliding post 13 to move up and down reciprocally through the two L-plates on it. When the sliding post 13 drives the piston 14 and the two first neodymium magnets 15 on it to move upward, the air between the piston 14 and the upper sealing cover 12 is compressed. At this time, the air is compressed again, and at the same time, the upper second neodymium magnet 16 and the first neodymium magnet 15 on the piston 14 repel each other. When the sliding post 1 When piston 14 begins to move downward, the air between piston 14 and upper sealing cover 12 returns to its initial pressure. At the same time, the second neodymium magnet 16 and the first neodymium magnet 15 on the upper side exert a repulsive force, thus providing initial downward force to piston 14 and sliding column 13. This causes sliding column 13 to rebound quickly. Then, sliding column 13 continues to move downward, and the air between piston 14 and lower sealing cover 12 is compressed again. By using piston 14 to compress air up and down, and through the magnetic force between second neodymium magnet 16 and adjacent first neodymium magnet 15, partial restoring force is provided to rotor bullet 6, thereby mitigating the problem of reduced rotor vibration frequency caused by reduced elasticity and mechanical strength of rotor bullet 6.

[0032] The technical principles of the embodiments of the present invention have been described above with reference to specific examples. These descriptions are merely for explaining the principles of the embodiments of the present invention and should not be construed as limiting the scope of protection of the embodiments of the present invention in any way. Based on the explanation herein, those skilled in the art can conceive of other specific embodiments of the present invention without creative effort, and these embodiments will all fall within the scope of protection of the embodiments of the present invention.

Claims

1. An energy-saving sonic motor for an electric toothbrush, comprising a motor housing (1), the motor housing (1) being rotatably connected to a rotating shaft (2), a stator core being mounted in the motor housing (1), a rotor being mounted on the rotating shaft (2), a rear housing (3) being fixedly connected to the motor housing (1), a coil lead on the stator core in the motor housing (1) being connected to a mainboard wire of the electric toothbrush, a fixing ring being fixedly connected in the rear housing (3), characterized in that: It also comprises a connecting member (4), the connecting member (4) being rotatably connected to a fixing ring in the rear shell (3), a spline sleeve (5) being fixedly connected to a side of the connecting member (4) close to the rotating shaft (2), an end of the rotating shaft (2) close to the spline sleeve (5) being arranged as a spline, the rotating shaft (2) being spline-matched with the spline sleeve (5) through the spline thereon, a rotating spring sheet (6) being fixedly connected between a side of the connecting member (4) away from the spline sleeve (5) and the rear shell (3), a pressure sensor (7) being fixedly connected to the rotating spring sheet (6), a lead wire of the pressure sensor (7) passing through the rear shell (3), the lead wire of the pressure sensor (7) being connected to an electric wire of a main board of the electric toothbrush, the pressure sensor (7) being used to monitor vibration changes of the rotating spring sheet (6); The invention also comprises a rotating plate (8), wherein the rotating plate (8) is rotatably connected to the spline sleeve (5), the rotating plate (8) and the connecting member (4) are mutually fitted, a symmetrical fixed column (9) is fixedly connected to one side of the rotating plate (8) close to the rotating shaft (2), a guide frame (10) is slidably connected to the fixed column (9), a symmetrical fixed tube (11) is fixedly connected inside the rear shell (3), both ends of the fixed tube (11) are fixedly connected to a sealing cover (12), a sliding column (13) is slidably connected between adjacent sealing covers (12), the sliding column (13) is located inside the fixed tube (11), a piston (14) is fixedly connected to the sliding column (13), the piston (14) is sealed and slidably connected to the adjacent fixed tube (11), air with an initial pressure greater than normal pressure is injected between the piston (14) and the adjacent sealing cover (12), and both ends of the sliding column (13) are respectively fixedly connected to the adjacent guide frame (10) through an L plate.

2. The energy-saving sonic motor for an electric toothbrush according to claim 1, characterized in that: The rotor spring (6) is made of stainless steel and is used to ensure that the rotating shaft (2) generates stable vibration.

3. An energy-saving sonic motor for an electric toothbrush according to claim 2, characterized in that: The fixed column (9) is fixedly connected to a mounting plate, the mounting plate of the fixed column (9) is slidably matched with the adjacent guide frame (10), and a ball bearing for reducing friction is installed between the fixed column (9) and the adjacent guide frame (10).

4. The energy-saving sonic motor for an electric toothbrush according to claim 3, characterized in that: A sealing ring is installed on the outer side of the piston (14) to keep the air pressure on both sides of the piston (14) the same.

5. The energy-saving sonic motor for an electric toothbrush according to claim 4, characterized in that: A seal is installed between the fixed tube (11) and the adjacent sealing cover (12), and a seal is installed between the sealing cover (12) and the adjacent sliding column (13) to prevent air leakage on both sides of the piston (14).

6. The energy-saving sonic motor for an electric toothbrush according to claim 5, characterized in that: It also includes four first neodymium magnets (15), which are respectively fixed to two sides of the piston (14) symmetrically. A second neodymium magnet (16) is fixed to one side of the sealing cover (12) close to the adjacent piston (14), and the opposite ends of the second neodymium magnet (16) and the adjacent first neodymium magnet (15) have the same magnetic poles.

7. An energy-saving sonic motor for an electric toothbrush according to claim 6, characterized in that: The first neodymium magnet (15) and the second neodymium magnet (16) are both arranged in a ring shape, and the first neodymium magnet (15) and the second neodymium magnet (16) are not in contact with the adjacent sliding column (13), thereby reducing the wear of the sliding column (13).

8. The energy-saving sonic motor for an electric toothbrush according to claim 7, characterized in that: The electric toothbrush further comprises a micro motor (17), the micro motor (17) being fixedly connected to the rear housing (3), the micro motor (17) being electrically connected to the main board of the electric toothbrush, the rear housing (3) being rotatably connected to a lead screw (18), the output shaft of the micro motor (17) being fixedly connected to the lead screw (18), the connecting member (4) being provided with symmetrical through holes, the through holes of the connecting member (4) being slidably connected to limit posts (19), the symmetrical limit posts (19) being fixedly connected to a rotating ring (20), the rotating plate (8) being provided with symmetrical blind holes, the limit posts (19) being limitedly matched with the blind holes adjacent to the rotating plate (8), the rotating ring (20) being rotatably connected to a connecting ring (21) on a side away from the spline sleeve (5), the connecting ring (21) being threadedly connected to the lead screw (18) via a mounting plate.

9. An energy-saving sonic motor for an electric toothbrush according to claim 8, characterized in that: An inclined annular surface is provided at one end of the limiting column (19) close to the rotating plate (8), so as to facilitate the insertion of the limiting column (19) into the adjacent blind hole of the rotating plate (8).

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