Motor and oral cleaning device
By adjusting the central angle and spacing of the magnets in the motor, the cogging torque is reduced and the motor swing angle is increased, thus solving the problem of insufficient swing amplitude of the electric toothbrush motor and achieving a more efficient teeth cleaning effect.
Patent Information
- Application Number
- CN202520341080.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-27
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-02-27
AI Technical Summary
Existing electric toothbrush motors have a small oscillation range, which cannot effectively clean the tooth surface, especially when performing the Bass brushing technique, as they cannot achieve the required 45-60 degree angle.
A motor structure was designed that reduces cogging torque and increases electromagnetic force by adjusting the central angle and spacing of the center lines of two magnets in the same group, thereby increasing the swing angle of the motor and driving the cleaning attachment through the rotor shaft to achieve a greater cleaning range.
The motor's output torque and load-bearing capacity were improved, the swing amplitude of the cleaning attachments was increased, and the cleaning ability of the oral cleaning equipment was enhanced.
Smart Images
Figure CN223829210U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the technical field of oral cleaning devices, and in particular to a motor and an oral cleaning device. BACKGROUND
[0002] An electric toothbrush can effectively clean teeth and oral cavity by high-frequency vibration of a brush head generated by rapid rotation or vibration of a motor, and thus has been favored by more and more consumers due to improved cleaning ability compared with a traditional toothbrush.
[0003] The motor of an existing electric toothbrush has a small swing range, and thus cannot effectively clean the surface of teeth. For example, the world-recognized correct Bass toothbrushing method requires that the bristles form an angle of 45-60 degrees with the teeth. Therefore, how to increase the swing range of the motor of an electric toothbrush is a problem to be solved in the field. UTILITY MODEL CONTENT
[0004] The present disclosure aims to overcome the deficiencies of the prior art and provide a motor and an oral cleaning device.
[0005] According to a first aspect of the present disclosure, a motor is provided, which comprises:
[0006] a rotor shaft;
[0007] a rotor member fixedly arranged on the rotor shaft and having two winding mounting arms extending in opposite directions in a radial direction of the rotor shaft, the winding mounting arms being configured to mount windings;
[0008] a stator assembly arranged around the rotor member;
[0009] two groups of magnets arranged on the stator assembly and corresponding to the two winding mounting arms respectively, and each group of magnets comprising two magnetically opposite magnets;
[0010] In at least one plane perpendicular to the rotation axis of the rotor shaft, the central angle a of the center lines of the two magnets in the same group, with the intersection of the rotation axis and the plane as the center, ranges from 40° to 50°.
[0011] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the central angle a of the center lines of the two magnets in the same group, with the intersection of the rotation axis and the plane as the center, ranges from 44.5° to 45.5°.
[0012] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the included angle β between the adjacent sides of the two magnets in the same group ranges from 35° to 45°.
[0013] In one embodiment of the present disclosure, the single-side swing angle of the rotor member ranges from 5° to 15°.
[0014] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the minimum value H1 of the side-to-side spacing of the two magnets in the same group and the width H2 of the winding mounting arm of the corresponding rotor member have a ratio ranging from 1: (1.15-1.22).
[0015] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the minimum value H1 of the side-to-side spacing of the two magnets in the same group ranges from 4mm to 5mm.
[0016] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the minimum value H1 of the side-to-side spacing of the two magnets in the same group ranges from 4.55mm to 4.75mm.
[0017] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the rotor member comprises a circular ring surrounding portion fixed on the rotor shaft, the winding mounting arm comprises an arm stem portion extending radially from the circular ring surrounding portion towards the stator assembly side, and two stop portions extending in the opposite direction circumferentially from the arm stem portion, and the winding is wrapped around the arm stem portion.
[0018] In one embodiment of the present disclosure, when in the balanced position, the two magnets in the same group are symmetrically arranged relative to the arm stem portion of the corresponding winding mounting arm, and the two magnets in the same group and the winding mounting arm overlap in the projection portion of the radial center projection with the rotation axis point as the projection center.
[0019] In one embodiment of the present disclosure, after the winding is energized, in the swing range of the rotor member around the rotor shaft relative to the stator assembly under the magnetic force, the stator assembly side towards the rotor member is a circular arc surface, the winding mounting arm side towards the stator assembly is a circular arc surface, and the radial air gap between the two circular arc surfaces ranges from 0.1mm to 0.2mm.
[0020] In one embodiment of the present disclosure, the winding mounting arm side towards the stator assembly is provided with a groove extending along the rotation axis on the circular arc surface, and when in the balanced position, the groove is located between the two magnets in the same group.
[0021] In one embodiment of the present disclosure, the motor further comprises an insulation layer arranged between the winding and the winding mounting arm of the rotor member.
[0022] In one embodiment of the present disclosure, the width H2 of the winding mounting arm of the rotor member is 5mm to 6mm in at least one plane perpendicular to the rotation axis of the rotor shaft.
[0023] In one embodiment of the present disclosure, the width H2 of the winding mounting arm of the rotor member is 5.45mm to 5.55mm in at least one plane perpendicular to the rotation axis of the rotor shaft.
[0024] In one embodiment of the present disclosure, the stator assembly further comprises a housing and a fixing seat shaped to fit the housing, and the magnet is fixedly arranged in the fixing seat.
[0025] In at least one plane perpendicular to the rotation axis of the rotor shaft, the housing has a swing space for the rotor member to swing around the rotor shaft relative to the magnet, the swing space is formed by two circular arc segments and two straight line segments, and the two circular arc segments are concentrically arranged with the rotation axis of the rotor shaft, and the two straight line segments are parallel to the extension direction of the winding mounting arm in the balanced position.
[0026] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the cross-sectional shape of the magnet is in the shape of a circular arc, the magnet comprises an outer circular arc segment, an inner circular arc segment distributed in the radial direction, and two side edges respectively connecting the corresponding two ends of the outer circular arc segment and the inner circular arc segment; the corresponding central angles of the outer circular arc segment and the inner circular arc segment are the same.
[0027] In one embodiment of the present disclosure, in at least one plane perpendicular to the rotation axis of the rotor shaft, the length of the side edge is 1mm to 1.5mm.
[0028] In one embodiment of the present disclosure, the rotor shaft is configured to have a fluid channel extending along the extension direction of the rotor shaft.
[0029] In one embodiment of the present disclosure, when the rotor shaft is driven by a torque component in the circumferential direction of the rotation axis, the rotor shaft rotates to a first preset position in the direction of the torque component, and then when driven by a torque component in the opposite direction, the rotor shaft rotates to a second preset position in the opposite direction.
[0030] According to a second aspect of the present disclosure, an oral cleaning device is provided, the oral cleaning device comprising a main body, a cleaning accessory movably arranged on the main body, and a motor arranged in the main body, the motor being configured to drive the cleaning accessory to swing through a rotor shaft, characterized in that the motor is the motor described in any one of the above embodiments.
[0031] In one embodiment of the present disclosure, the oral cleaning device further comprises a pump, an outlet end of the pump being in communication with the fluid passage of the rotor shaft.
[0032] One beneficial effect of the motor of the present disclosure is that, due to the existence of cogging torque, the greater the swing angle, the smaller the electromagnetic force, the motor adjusts the central angle of the center of the two magnets in the same group by means of a special structure, changes the distance between the two magnets, the greater the central angle, the greater the distance between the magnets, and the farther the center position of the magnet from the winding mounting arm, the cogging torque decreases, the electromagnetic force of the motor increases, thereby increasing the angle of reciprocating swing. And due to the reduction of cogging torque, the electromagnetic force of the motor that overcomes the cogging torque during rotation is reduced, the electromagnetic force acting on the output torque of the motor is increased, the efficiency of the motor is improved, the output torque of the motor is improved, and the load capacity of the motor is improved.
[0033] It should be noted that the oral cleaning device of the present disclosure comprises the above-mentioned motor, has the same technical effect as the motor of the present disclosure, and will not be described here. In addition, the oral cleaning device of the present disclosure further comprises a pump, an outlet end of the pump being in communication with the fluid passage of the rotor shaft, the pump provides sufficient pressure to send water or special cleaning liquid to the cleaning accessory, and the oral cleaning device uses liquid to help remove food residues and dental plaque between teeth, thereby improving the cleaning ability of the oral cleaning device for the oral cavity. BRIEF DESCRIPTION OF DRAWINGS
[0034] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0035] Figure 1 is a first radial cross-sectional view of the motor provided in an embodiment of the present disclosure;
[0036] Figure 2 is a second radial cross-sectional view of the motor provided in an embodiment of the present disclosure;
[0037] Figure 3 is a perspective view of the motor provided in an embodiment of the present disclosure;
[0038] Figure 4 is an axial cross-sectional view of the motor provided in an embodiment of the present disclosure;
[0039] Figure 5 is a third radial cross-sectional view of the motor provided in an embodiment of the present disclosure.
[0040] Figures 1-5 The one-to-one correspondence between the names of the components in the figure and the reference numerals is as follows:
[0041] 1-rotor shaft; 11-fluid passage;
[0042] 2 - rotor member; 21 - winding mounting arm; 211 - arm stem portion; 212 - stop portion; 2121 - groove; 22 - winding; 23 - circular ring portion;
[0043] 3 - stator assembly; 31 - fixing seat; 32 - housing;
[0044] 4 - magnet; 5 - insulation layer. DETAILED DESCRIPTION
[0045] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of the components and steps set forth in these embodiments, the numerical expressions, and the numerical values are not limiting to the scope of the present disclosure unless otherwise specifically stated.
[0046] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way limiting to the scope of the disclosure and its applications or uses.
[0047] Techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail herein, but should be considered as part of the specification, where appropriate.
[0048] In all of the examples shown and discussed herein, any specific values should be interpreted as merely illustrative and not as a limitation. Thus, other examples of exemplary embodiments can have different values.
[0049] It should be noted that like numbers and letters refer to like items throughout the drawings, and that, as such, no further discussion on these items is required.
[0050] In this document, "upper", "lower", "front", "rear", "left", "right", and the like, are used to describe relative positions between the relevant parts, and are not intended to limit the absolute positions of these relevant parts.
[0051] In this document, "first", "second", and the like, are used to distinguish between the relevant parts from each other, and are not intended to indicate the importance and order, and the premise of each other.
[0052] In this document, "equal", "same", and the like, are not strictly limited in the mathematical and / or geometric sense, but also include the errors that can be understood by those skilled in the art and allowed by manufacturing or use, etc.
[0053] In this document Figure 1 , Figure 2 , Figure 5For the same cross-sectional view, in order to clearly mark the structure and size parameters, it is divided into a first radial cross-sectional view, a second radial cross-sectional view, and a third radial cross-sectional view.
[0054] It should be noted that, in order to better understand the technical solutions of the present disclosure, first, the orientation word setting rules and professional terms involved in the present disclosure are explained.
[0055] In the present disclosure, axial refers to the direction along the rotation axis of the rotor, circumferential refers to the circumferential direction around the rotation axis of the rotor, and radial refers to the direction extending outward from the rotation center in a plane perpendicular to the rotation axis of the rotor.
[0056] Cogging torque: Cogging torque is the torque generated by the interaction between the permanent magnet and the stator core when the winding of the permanent magnet motor is not powered on. It is caused by the tangential component of the interaction force between the permanent magnet and the armature teeth.
[0057] Duty cycle: Duty cycle refers to the ratio of energization time to total time within one pulse cycle.
[0058] The existing motor of the electric toothbrush has a small swing amplitude. Therefore, the present disclosure provides a motor and an oral cleaning device. In order to facilitate understanding, the specific structure and working principle of the motor and the oral cleaning device of the present disclosure will be described in detail below with reference to Figures 1-5
[0059] The motor of the present disclosure comprises a rotor shaft 1, a rotor member 2, a stator assembly 3, and two groups of magnets. The rotor member 2 is fixedly arranged on the rotor shaft 1 and has two winding mounting arms 21 extending in opposite directions along the radial direction of the rotor shaft 1, and the winding mounting arms 21 are configured to mount windings 22. The stator assembly 3 is arranged around the rotor member 2. The two groups of magnets are arranged on the stator assembly 3 and correspond to the two winding mounting arms 21, respectively, and each group of magnets comprises two magnetically opposite magnets 4. In at least one plane perpendicular to the rotation axis of the rotor shaft 1, with the intersection of the rotation axis and the plane as the center, the central angle α of the center lines of the two magnets 4 in the same group ranges from 40° to 50°.
[0060] The motor disclosed herein, due to the presence of cogging torque, exhibits a decreasing electromagnetic force as the oscillation angle increases. This motor utilizes a special structural setting to adjust the central angle α of the center lines of two magnets 4 within the same group, altering the distance between the two magnets 4. A larger central angle α results in a larger distance between the magnets 4, and simultaneously, a greater distance between the center positions of the magnets 4 and the winding mounting arm 21, leading to a decrease in cogging torque and an increase in the motor's electromagnetic force, thereby increasing the reciprocating oscillation angle. Furthermore, due to the reduction in cogging torque, the electromagnetic force required to overcome the cogging torque during motor rotation decreases, while the electromagnetic force acting on the motor's output torque increases, thus improving motor efficiency, increasing output torque, and enhancing the motor's load-bearing capacity.
[0061] When the motor is not powered on, the rotor component 2 is in the initial position. At this time, the center of the winding mounting arm 21 is furthest from the magnet 4, and the cogging torque is minimal. Due to the small cogging torque during startup, the motor's starting characteristics are superior. When the motor's electromagnetic torque overcomes the cogging torque output, the swing angle of the rotor component 2 can be controlled. The electromagnetic conversion process is relatively simple and direct. When a control signal is received, the motor can react quickly to achieve the change in rotation angle.
[0062] See Figure 1 , Figure 2 The motor disclosed herein comprises a rotor shaft 1, a rotor component 2, a stator assembly 3, and magnets 4. The winding mounting arm 21 is designed to be symmetrically arranged with a set of two magnets 4. The rotor component 2 and the stator assembly 3 achieve energy conversion through electromagnetic interaction, resulting in a compact structure and efficient torque output.
[0063] The rotor shaft 1 is typically made of high-strength alloy steel with a hardened surface. Both ends are fixed to the motor housing 32 by precision ball bearings.
[0064] Furthermore, the rotor shaft 1 is configured to have a fluid channel 11 extending along the extension direction of the rotor shaft 1. The fluid channel 11 can be straight, spiral, or other shapes depending on design requirements. Taking a straight shape as an example, the fluid channel 11 is a circular channel coaxial with the rotor shaft 1. When liquid passes through the fluid channel 11, the high-speed rotating rotor shaft 1 and the fluid channel 11 still maintain rotation around the axial direction without deviation, thus keeping the rotor shaft 1, the fluid channel 11, and the liquid passing through the fluid channel 11 stable during operation. The fluid channel 11 can use a pump or other driving element to deliver water or cleaning fluid to the cleaning attachment connected to the rotor shaft 1, improving cleaning capability.
[0065] The rotor component 2 is integrally cast from a magnetically conductive material and includes a central circular ring 23 and a winding mounting arm 21 extending radially from the circular ring 23 in the opposite direction along the rotor shaft 1. The circular ring 23 is fixedly connected, and the winding 22 is mounted around the winding mounting arm 21.
[0066] The stator assembly 3 is generally formed by a plurality of annular silicon steel sheets stacked together and surrounds the rotor member 2. The stator assembly 3 further comprises a housing 32 and a fixing base 31 which is shaped to fit the housing 32, and the magnets 4 are fixedly arranged in the fixing base 31. In at least one plane perpendicular to the rotation axis of the rotor shaft 1, the housing 32 has a swing space for the rotor member 2 to swing around the rotor shaft 1 relative to the magnets 4, and the swing space is formed by two circular arc segments and two straight line segments, the two circular arc segments are concentrically arranged with the rotation axis of the rotor shaft 1, and the two straight line segments are parallel to the extension direction of the winding mounting arm 21 in the balanced position. The circular arc segments of the housing 32 are adapted to the circular arc segments of the winding mounting arm 21, so that the rotor member 2 swings at the position of the circular arc segments of the housing 32, and the straight line segments are arranged to compress the space of the motor, so that the overall structure of the housing 32 of the motor is compact.
[0067] The magnets 4 are symmetrically designed with the winding mounting arm 21, and one winding mounting arm 21 corresponds to two magnets 4 of the same group with opposite magnetic properties, and is fixedly arranged on the fixing base 31 of the stator assembly 3. The cross-sectional shape of the fixing base 31 is the same as that of the housing 32, so that the fixing base 31 can be inserted into the housing 32 for fixation. By changing the fixed position of the magnets 4 on the fixing base 31, the spacing between the magnets 4 can be adjusted.
[0068] Since the cogging torque is affected by the arrangement position of the magnets 4, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the center angle a of the center lines of the two magnets 4 in the same group is 40° to 50° with the rotation axis as the center.
[0069] When the rotor shaft 1 is driven by a torque component along the circumferential direction of the rotation axis, the rotor shaft 1 rotates in the direction of the torque component to a first preset position, and then when it is driven by a torque component in the opposite direction, the rotor shaft 1 rotates in the opposite direction to a second preset position. The first preset position is the position where the single-side swing angle of the rotor member 2 reaches the maximum value, and the second preset position is the position where the rotor member 2 rotates in the opposite direction and the single-side swing angle reaches the maximum value.
[0070] Working principle:
[0071] Reference Figure 1, when the rotor member 2 is in the balanced position, the position of the rotor member 2 is taken as the 0° angle position, i.e. the initial position, and the cogging torque is also 0 or close to 0. The rotor member 2 is deflected by an angle θ from the 0° angle position as the starting point to one side, and the angle θ is the single-side swing angle of the rotor member 2. When a positive current is applied to the motor, the electromagnetic torque pushes the rotor member 2 to swing counterclockwise, the cogging torque is opposite to the electromagnetic torque, and during the swinging process of the rotor member 2, the cogging torque gradually increases, when the single-side swing angle of the rotor member 2 exceeds the preset swing angle value, the cogging torque increases to be equal to the electromagnetic torque, at this time, the output torque is 0, and the single-side swing angle of the rotor member 2 reaches the maximum value. When a reverse current is applied to the motor, the electromagnetic torque pushes the rotor member 2 to swing clockwise, after passing through the 0° angle position, the cogging torque is opposite to the electromagnetic torque, which is the same as when the rotor member 2 swings counterclockwise, when the single-side swing angle of the rotor member 2 exceeds the preset swing angle value, the cogging torque increases to be equal to the electromagnetic torque, at this time, the output torque is 0, and the single-side swing angle of the rotor member 2 reaches the maximum value. Then, the above process is repeated. The preset swing angle value is the maximum value of the single-side swing angle.
[0072] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the central angle α of the center lines of the two magnets 4 in the same group ranges from 44.5° to 45.5° with the rotation axis of the rotor shaft 1 and the intersection of the plane as the center.
[0073] Specifically, through repeated experiments, when the central angle α of the center lines of the two magnets 4 in the same group ranges from 44.5° to 45.5°, the cogging torque is reduced, the electromagnetic force of the motor is increased, the maximum value of the single-side swing angle of the rotor member 2 can reach the required value, and the performance of the motor is relatively optimal.
[0074] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the included angle β between the adjacent sides of the two magnets 4 in the same group ranges from 35° to 45°.
[0075] Referring to Figure 2 , Figure 5 Specifically, in the case where the central angle α of the center lines of the two magnets 4 in the same group is determined, the included angle β between the adjacent sides of the two magnets 4 in the same group determines the minimum value of the shape and side spacing of the magnet 4. Through repeated experiments, when the included angle β between the adjacent sides of the two magnets 4 in the same group ranges from 35° to 45°, the cogging torque is reduced, the maximum value of the single-side swing angle of the rotor member 2 can reach the required value, and the performance of the motor is relatively optimal.
[0076] In one embodiment, the single-side swing angle of the rotor member 2 ranges from 5° to 15°.
[0077] Referring toFigure 1 , specifically, by adjusting the central angle a of the center line of the two magnets 4 in the same group and the included angle β between the adjacent sides of the two magnets 4 in the same group within the preset value, the single side swing angle of the rotor member 2 is 5° to 15°, the maximum single side swing angle of the rotor member 2 is 15°, and the rotor shaft 1 can carry the cleaning accessory to achieve a cleaning range of 30°. In addition, due to the small cogging torque at start-up, when the electromagnetic torque of the motor overcomes the cogging torque output, the rotor member 2 can be controlled to swing between -15° and 15°, and various swing modes can be adjusted.
[0078] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the ratio of the minimum value H1 of the side spacing of the two magnets 4 in the same group to the width H2 of the winding mounting arm 21 of the corresponding rotor member 2 is 1: (1.15-1.22).
[0079] Referring to Figure 2 , Figure 5 , specifically, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, due to the non-parallel sides of the two magnets 4, the side spacing is small near the axis and large away from the axis, and H1 is defined as the minimum value of the side spacing of the two magnets 4 in the same group, and H2 is the width of the arm rod part 211 of the winding mounting arm 21. In at least one plane perpendicular to the rotation axis of the rotor shaft 1, the ratio of the minimum value H1 of the side spacing of the two magnets 4 in the same group to the width H2 of the winding mounting arm 21 of the corresponding rotor member 2 is 1: (1.15-1.22), by limiting the relative size, the relative size of the spacing between the magnets 4 and the size of the winding mounting arm 21 is determined, so that the magnetic flux in the winding 22 and the magnetic field distribution meet the design requirements.
[0080] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the minimum value H1 of the side spacing of the two magnets 4 in the same group is 4mm to 5mm.
[0081] Specifically, the minimum value H1 of the side spacing of the two magnets 4 in the same group directly affects the magnetic field distribution generated by the magnets 4 and indirectly affects the magnetic flux of the winding 22, and through multiple experiments, the cogging torque and electromagnetic force of the motor meet the design requirements.
[0082] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the minimum value H1 of the side spacing of the two magnets 4 in the same group is 4.55mm to 4.75mm.
[0083] Specifically, through repeated experiments, when the minimum value H1 of the side spacing between two magnets 4 in the same group is 4.55mm to 4.75mm in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the cogging torque is reduced, the maximum single-side swing angle of the rotor member 2 can reach the required value, and the performance of the motor is relatively optimal.
[0084] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the rotor member 2 comprises a circular ring portion 23 surrounding the rotor shaft 1, the winding mounting arm 21 comprises an arm rod portion 211 extending radially from the circular ring portion 23 towards the side of the stator assembly 3, and two stop portions 212 extending in the opposite direction from the arm rod portion 211, and the winding 22 is wound around the arm rod portion 211.
[0085] Referring to Figure 2 Specifically, the circular ring portion 23 is the connecting part of the rotor member 2 and the rotor shaft 1, mainly used to provide sufficient mechanical strength to support other components on the rotor member 2, and is fixedly connected with the rotor shaft 1 to drive the winding mounting arm 21 to swing.
[0086] The arm rod portion 211 is an intermediate portion on the rotor member 2, formed by extending the circular ring portion 23 in the opposite radial direction, and is symmetrically arranged on both sides of the rotor shaft 1 of the motor, and the winding 22 is wound on the arm rod portion 211.
[0087] The free end of each arm rod portion 211 extends in the circumferential direction to form two stop portions 212, and the two stop portions 212 and the free end of the arm rod portion 211 form a complete circular arc segment, the projection length of the circular arc segment in the radial direction is greater than the width of the arm rod portion 211, the winding 22 is clamped on the arm rod portion 211, and the winding 22 is prevented from falling off the arm rod portion 211.
[0088] In one embodiment, when in the balanced position, the two magnets 4 in the same group are symmetrically arranged relative to the arm rod portion 211 of the corresponding winding mounting arm 21, and the two magnets 4 in the same group and the winding mounting arm 21 overlap in the projection part of the central projection along the radial direction with the point of the rotation axis as the projection center.
[0089] Specifically, when in the balanced position, the distance between the two magnets 4 in the same group and the winding mounting arm 21 is equal, and in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the two magnets 4 in the same group and the winding mounting arm 21 are centrally symmetric with the point of the rotation axis as the center, so that the magnetic field distribution generated by the magnets 4 is uniform, which is conducive to the relevant experiments of the motor, and the cogging torque of the motor is 0 or close to 0 at this time, and the starting performance of the motor can be improved when starting from the balanced position, and the motor can control the swing angle of the rotor member 2 through electromagnetic force.
[0090] In one embodiment, the winding 22 is energized, and under the magnetic force, the rotor member 2 swings within the swing range of the rotor shaft 1 relative to the stator assembly 3, the side of the stator assembly 3 facing the rotor member 2 is a circular surface, the side of the winding mounting arm 21 facing the stator assembly 3 is a circular arc surface, and the radial air gap between the two circular arc surfaces ranges from 0.1 mm to 0.2 mm.
[0091] Specifically, the width of the radial air gap affects the magnetic circuit characteristics of the motor, thereby affecting the cogging torque of the motor. When the width of the radial air gap increases, the magnetic resistance of the motor also increases due to the increase in the magnetic circuit length between the stator assembly 3 and the rotor member 2, thereby resulting in a decrease in the cogging torque of the motor. The width of the radial air gap also affects the electromagnetic induction characteristics of the motor, thereby affecting the cogging torque of the motor. When the width of the radial air gap increases, the magnetic field strength of the motor also decreases due to the decrease in the magnetic flux density of the rotor member 2, thereby resulting in a decrease in the cogging torque of the motor. Therefore, increasing the width of the radial air gap can effectively reduce the cogging torque.
[0092] However, increasing the width of the radial air gap will result in a decrease in the efficiency and maximum torque of the motor, so it is necessary to reasonably select the width range of the radial air gap. Preferably, the motor of the present disclosure adopts a radial air gap width range of 0.1 mm to 0.2 mm, which achieves the purpose of reducing the cogging torque of the motor while ensuring that the efficiency and maximum torque of the motor meet the working requirements.
[0093] In one embodiment, the side of the winding mounting arm 21 facing the stator assembly 3 is provided with a groove 2121 extending along the rotation axis, and when in the balanced position, the groove 2121 is located between the two magnets 4 of the same group.
[0094] Specifically, the motor generates heat during operation, and heat has a great impact on the performance of the motor. The groove 2121 can increase the surface area of the winding mounting arm 21, which helps the heat to dissipate more quickly. The groove 2121 design can improve the mechanical strength of the winding mounting arm 21 and reduce the risk of damage to the rotor member 2 due to vibration during rotation. The groove 2121 can also be used to more firmly fix the winding 22 to prevent displacement or loosening during operation of the motor.
[0095] In one embodiment, the motor further comprises an insulation layer 5 arranged between the winding 22 and the winding mounting arm 21 of the rotor member 2.
[0096] Specifically, the direct contact between the winding mounting arm 21 and the winding 22 can cause short circuit and other accidents, and in order to prevent current leakage of the winding 22. Therefore, in order to improve the insulation performance of the winding 22 and other components, an insulation layer 5 is arranged between the winding 22 and the winding mounting arm 21 of the rotor member 2, the insulation layer 5 covers part of the circular ring portion 23, the arm rod portion 211 and the stop portion 212 of the winding mounting arm 21, and only the side of the stop portion 212 close to the stator assembly 3 and the circular arc segment formed by the free end of the arm rod portion 211 are exposed. The insulation performance is greatly improved.
[0097] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the width H2 of the winding mounting arm 21 of the rotor member 2 is 5mm to 6mm.
[0098] Specifically, the width H2 of the winding mounting arm 21 of the rotor member 2 directly affects the magnetic flux of the winding 22, and affects the electromagnetic force and the cogging torque of the motor. Through multiple experiments, the cogging torque and the electromagnetic force of the motor meet the design requirements.
[0099] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the width H2 of the winding mounting arm 21 of the rotor member 2 is 5.45mm to 5.55mm.
[0100] Specifically, through multiple experiments, when the width H2 of the winding mounting arm 21 of the rotor member 2 is 5.45mm to 5.55mm in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the cogging torque is reduced, the maximum single-side swing angle of the rotor member 2 can meet the required demand, and the performance of the motor is better.
[0101] In one embodiment, in at least one plane perpendicular to the rotation axis of the rotor shaft 1, the cross-sectional shape of the magnet 4 is in the shape of a circular arc, the magnet 4 includes an outer circular arc segment, an inner circular arc segment distributed in the radial direction, and two side edges respectively connecting two ends of the outer circular arc segment and the inner circular arc segment; the central angles of the outer circular arc segment and the inner circular arc segment are the same.
[0102] Specifically, the central angles of the outer circular arc segment and the inner circular arc segment are the same, that is, the inner and outer circular arcs are concentric, only the radii are different, which helps to ensure the consistency of the magnetic field in the radial direction, so that the magnetic field inside the motor is more uniform. The two side edges not only connect the inner and outer circular arc segments, but also may cause unnecessary magnetic flux loss or interference due to the edge effect of the magnetic field, so the straight side edges are needed to facilitate the dimensional limitation of the side edges and reduce the impact on the magnetic field as much as possible. Uniform magnetic field can help the motor to achieve better performance. Therefore, the cross-sectional shape of the magnet 4 including the outer circular arc segment, the inner circular arc segment and the two side edges connecting the two segments is to ensure the uniformity of the magnetic field and maximize the use of space.
[0103] In one embodiment, the length of the side is 1mm to 1.5mm in at least one plane perpendicular to the rotation axis of the rotor shaft 1.
[0104] Specifically, the length of the side of the magnet 4 determines the size of the magnet 4, which is an important factor in determining the magnetic field distribution. Since the edge area of the magnet 4 usually has a stronger local magnetic field change, the magnetic field generated in the length direction may be more uniform as the length of the magnet 4 increases, and the magnetic force line has more paths to follow instead of concentrating at both ends. Therefore, by changing the length of the side of the magnet 4, the cogging torque of the motor can be changed. After multiple experiments, when the length of the side is 1mm to 1.5mm in at least one plane perpendicular to the rotation axis of the rotor shaft 1, and more preferably 1.2mm, the maximum single-side swing angle of the rotor member 2 can reach the required value, and the performance of the motor is better.
[0105] In addition to the above-mentioned motor applied to the oral cleaning device, the present disclosure also provides an oral cleaning device, which comprises a main body, a cleaning accessory movably arranged on the main body, and a motor arranged in the main body, the motor being configured to drive the cleaning accessory to swing through the rotor shaft 1, characterized in that the motor is the motor described in any one of the above-mentioned embodiments.
[0106] Specifically, the oral cleaning device includes an electric toothbrush, an electric water pick, a tongue cleaner and the like. The use of the motor of the present disclosure can improve the load resistance of the oral cleaning device and stabilize the operation, while increasing the swing amplitude of the cleaning accessory and improving the cleaning ability of the oral cleaning device for the oral cavity.
[0107] In one embodiment, the oral cleaning device further comprises a pump, and the outlet of the pump is in communication with the fluid channel 11 of the rotor shaft 1.
[0108] Specifically, the oral cleaning device is further provided with a water tank, and the water tank is connected with the pump through a pipeline. The pump provides sufficient pressure to make the liquid pass through the pipeline, the fluid channel 11 of the rotor shaft 1 and reach the cleaning accessory. The oral cleaning device uses the liquid to help remove food residues and dental plaque between teeth, thereby improving the cleaning ability of the oral cleaning device for the oral cavity.
[0109] Having described above several embodiments of the disclosure, any modifications and variations that fall within the scope of the described embodiments are also contemplated by the inventor(s). As such, the foregoing description is not intended to limit the scope of the disclosure, and it is recognized that modifications to embodiments of the disclosure, as well as implementations of other embodiments of the disclosure, can be made by a person of ordinary skill in the art without departing from the spirit and scope of the disclosure. The choice of words in this document is intended to best describe the principles of the embodiments, the practical application, or technical improvements in the art, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of the disclosure is defined by the appended claims.
Claims
1. An electric motor, characterized in that, The motor includes: Rotor shaft (1); The rotor component (2) is fixedly disposed on the rotor shaft (1) and has two winding mounting arms (21) extending in opposite directions along the radial direction of the rotor shaft (1), the winding mounting arms (21) being configured to mount windings (22). Stator assembly (3), the stator assembly (3) being arranged around the rotor member (2); Two sets of magnets are disposed on the stator assembly (3) and respectively corresponding to the two winding mounting arms (21), and each set of magnets includes two magnets (4) with opposite magnetic properties. In at least one plane perpendicular to the rotation axis of the rotor shaft (1), with the intersection of the rotation axis and the plane as the center, the central angle α of the center lines of the two magnets (4) in the same group ranges from 40° to 50°.
2. The motor according to claim 1, characterized in that, In at least one plane perpendicular to the rotation axis of the rotor shaft (1), with the intersection of the rotation axis and the plane as the center, the central angle α of the center lines of the two magnets (4) in the same group ranges from 44.5° to 45.5°.
3. The motor according to claim 1 or 2, characterized in that, In at least one plane perpendicular to the axis of rotation of the rotor shaft (1), the included angle β between adjacent sides of two magnets (4) in the same group ranges from 35° to 45°.
4. The motor according to claim 3, characterized in that, The single-sided swing angle of the rotor component (2) ranges from 5° to 15°.
5. The motor according to claim 4, characterized in that, In at least one plane perpendicular to the rotation axis of the rotor shaft (1), the ratio of the minimum side spacing H1 of two magnets (4) in the same group to the width H2 of the winding mounting arm (21) of the corresponding rotor member (2) is 1: (1.15-1.22).
6. The motor according to claim 5, characterized in that, In at least one plane perpendicular to the axis of rotation of the rotor shaft (1), the minimum side spacing H1 of two magnets (4) in the same group is 4 mm to 5 mm.
7. The motor according to claim 6, characterized in that, In at least one plane perpendicular to the axis of rotation of the rotor shaft (1), the minimum side spacing H1 of the two magnets (4) in the same group is 4.55 mm to 4.75 mm.
8. The motor according to claim 5, characterized in that, In at least one plane perpendicular to the rotation axis of the rotor shaft (1), the rotor component (2) includes a circular circumferential portion (23) fixed to the rotor shaft (1), the winding mounting arm (21) includes an arm portion (211) extending radially from the circular circumferential portion (23) toward the stator assembly (3), and two stop portions (212) extending circumferentially in opposite directions from the arm portion (211), the winding (22) being wrapped around the arm portion (211).
9. The motor according to claim 5, characterized in that, When in the equilibrium position, the two magnets (4) of the same group are symmetrically arranged with respect to the arm part (211) of the corresponding winding mounting arm (21), and the two magnets (4) of the same group overlap with the projection part of the winding mounting arm (21) which is projected radially with the point of the rotation axis as the projection center.
10. The motor according to claim 7, characterized in that, After the winding (22) is energized, under the action of magnetic force, the rotor component (2) swings around the rotor shaft (1) relative to the stator assembly (3) within the swing range. The stator assembly (3) facing the rotor component (2) is an arc surface, and the winding mounting arm (21) facing the stator assembly (3) is an arc surface. The radial air gap between the two arc surfaces is 0.1 mm to 0.2 mm.
11. The motor according to claim 8, characterized in that, The winding mounting arm (21) facing the stator assembly (3) has a groove (2121) extending along the rotation axis on its arc surface, and when it is in the equilibrium position, the groove (2121) is located between the two magnets (4) in the same group.
12. The motor according to claim 8, characterized in that, The motor also includes an insulation layer (5) disposed between the winding (22) and the winding mounting arm (21) of the rotor component (2).
13. The motor according to claim 5, characterized in that, In at least one plane perpendicular to the rotation axis of the rotor shaft (1), the width H2 of the winding mounting arm (21) of the rotor component (2) is 5 mm to 6 mm.
14. The motor according to claim 13, characterized in that, In at least one plane perpendicular to the rotation axis of the rotor shaft (1), the width H2 of the winding mounting arm (21) of the rotor component (2) is 5.45 mm to 5.55 mm.
15. The motor according to claim 1, characterized in that, The stator assembly (3) also includes a housing (32) and a mounting base (31) adapted to the shape of the housing (32), and the magnet (4) is fixedly disposed in the mounting base (31); In at least one plane perpendicular to the rotation axis of the rotor shaft (1), the housing (32) has a swing space that provides the rotor component (2) with a swing space about the rotor shaft (1) relative to the magnet (4), the swing space being formed by two arc segments and two straight segments, the two arc segments being concentric with the rotation axis of the rotor shaft (1), and the two straight segments being parallel to the extension direction of the winding mounting arm (21) located at the equilibrium position.
16. The motor according to claim 1, characterized in that, In at least one plane perpendicular to the rotation axis of the rotor shaft (1), the cross-sectional shape of the magnet (4) is arc-shaped. The magnet (4) includes an outer arc segment and an inner arc segment distributed radially, and two side edges that respectively connect the two ends of the outer arc segment and the inner arc segment; the central angles of the outer arc segment and the inner arc segment are the same.
17. The motor according to claim 16, characterized in that, The length of the side is 1 mm to 1.5 mm in at least one plane perpendicular to the axis of rotation of the rotor shaft (1).
18. The motor according to claim 1, characterized in that, The rotor shaft (1) is configured to have a fluid passage (11) extending along the extension direction of the rotor shaft (1).
19. The motor according to claim 1, characterized in that, When the rotor shaft (1) is driven by a torque component along the circumferential direction of the rotation axis, the rotor shaft (1) rotates to a first preset position in the direction of the torque component. Subsequently, when driven by a torque component in the opposite direction, the rotor shaft (1) rotates to a second preset position in the opposite direction.
20. An oral hygiene device, characterized in that, The oral cleaning device includes a main body, a cleaning attachment movably disposed on the main body, and a motor disposed within the main body, the motor being configured to drive the cleaning attachment to swing via a rotor shaft (1), the motor being the motor according to any one of claims 1 to 19.
21. The oral hygiene device according to claim 20, characterized in that, The oral cleaning device also includes a pump, the outlet of which is connected to the fluid channel (11) of the rotor shaft (1).