Rotating mirror module

Abstract

The embodiment of the application discloses a rotating mirror module, which comprises a stator assembly, a rotor assembly and a rotating mirror. The stator assembly comprises a sleeve, an iron core, a base and an electric control board, and the rotor assembly comprises a shell, a rotating shaft, a cylindrical magnetic ring and an encoding disc. The sleeve is fixedly connected with the iron core and the base respectively, the electric control board is fixed on the base, and a photoelectric detection module is arranged on the electric control board. The photoelectric detection module is used for emitting detection light and receiving echo light formed by reflection of the detection light on the encoding disc. The shell is fixedly connected with the rotating mirror, the rotating shaft is in interference fit with the shell, the cylindrical magnetic ring is fixedly connected with the shell, the encoding disc is fixedly connected with the cylindrical magnetic ring, and the encoding disc is provided with a plurality of reflection areas and non-reflection areas which are arranged alternately. The rotating shaft is centrally arranged in the sleeve along the axial direction of the sleeve, and the iron core is arranged in the interior of the cylindrical magnetic ring. The rotating mirror module adopts a reflection type photoelectric detection module and a detachable stator assembly, can fully utilize the installation space, and is favorable for compressing the volume of the rotating mirror module.

Description

Technical Field

[0001] This application relates to the field of laser scanning equipment technology, and in particular to a rotating mirror module. Background Technology

[0002] The rotating mirror module is a crucial component of laser scanning systems, widely used in laser printers, barcode scanners, lidar, and laser displays. The rotating mirror module primarily utilizes the interaction between an alternating magnetic field generated by a coil and a permanent magnet to produce a rotational torque, driving a reflector to oscillate at high speed, thereby achieving the deflection and scanning of the laser beam.

[0003] However, in existing rotating mirror modules, the overall size of the motor is relatively large due to limitations in structural design and assembly processes, which is not conducive to the miniaturization and lightweighting of the equipment. Summary of the Invention

[0004] The rotating mirror module of this application aims to solve the problem of the large size of existing rotating mirror modules.

[0005] In a first aspect, embodiments of this application provide a rotating mirror module. The rotating mirror module includes a stator assembly, a rotor assembly, and a rotating mirror. The stator assembly includes a sleeve, an iron core, a base, and an electronic control board. The rotor assembly includes a housing, a rotating shaft, a cylindrical magnetic ring, and an encoder disk. The sleeve is fixedly connected to both the iron core and the base. The electronic control board is fixed to the base and has a photoelectric detection module. The photoelectric detection module includes a light-emitting element and a photodetector. The light-emitting element emits detection light, and the photodetector receives the echo light formed by the detection light reflected by the encoder disk. The light-emitting element and the photodetector are located on the same side of the encoder disk. The housing is fixedly connected to the rotating mirror, the rotating shaft is interference-fitted to the housing, the cylindrical magnetic ring is fixedly connected to the housing, and the encoder disk is fixedly connected to the cylindrical magnetic ring. The encoder disk has multiple alternately arranged reflective and non-reflective areas. The rotating shaft passes centrally through the sleeve along its axial direction, and the iron core is located inside the cylindrical magnetic ring.

[0006] In some embodiments, the rotating mirror is disposed outside the housing, which includes a first end and a second end. The first end is the end of the housing away from the base, and the second end is the end of the housing close to the base. A first groove is formed on the outer surface of the first end, and the top of the rotating mirror is bonded to at least a portion of the outer surface of the first end. A limiting protrusion is provided at the first end, and a limiting through hole corresponding to the limiting protrusion is formed on the top of the rotating mirror, with the limiting protrusion passing through the limiting through hole.

[0007] By using the limiting protrusions that pass through the limiting through-hole, the circumferential positioning between the rotating mirror and the housing can be achieved, ensuring that the rotating mirror will not rotate relative to the housing during actual operation.

[0008] In some embodiments, the inner surface of the rotating mirror is covered with a black coating, and the rotor assembly and the electronic control board are located within the receiving space formed by the rotating mirror and the base.

[0009] The black coating covering the inner surface of the rotating mirror can effectively absorb stray light from the external environment, preventing stray light from being further reflected into the electronic control board and effectively reducing interference to the photoelectric detection module.

[0010] In some embodiments, the minimum circumcircle of the rotating mirror is covered by the radial plane projection of the base; wherein, the minimum circumcircle of the rotating mirror is the circumcircle of the projection of the rotating mirror along the axial direction of the rotating axis onto a radial plane perpendicular to the axial direction, and the radial plane projection of the base is the projection of the base along the axial direction onto a radial plane.

[0011] With this structural design, the base can completely cover the area swept by the rotating mirror during rotation, thereby further reducing the interference of stray light from the external environment on the photoelectric detection module.

[0012] In some embodiments, the encoder disk is an annular component with a circular mounting hole at its center. The projection of the mounting hole along the axial direction of the rotating shaft onto a horizontal plane covers the projection of the sleeve along the axial direction onto a horizontal plane. The diameter of the mounting hole is smaller than the inner diameter of the cylindrical magnetic ring.

[0013] The reduction in the diameter of the mounting holes allows for a corresponding reduction in the size of the encoder disk, which in turn effectively reduces the size of the motor, creating favorable conditions for the overall miniaturization of the rotating mirror module.

[0014] In some embodiments, the rotating mirror module further includes a bearing and a limiting component, the limiting component being used to limit the axial movement of the bearing; each bearing includes an inner bearing ring, an outer bearing ring, and a lubrication component, the lubrication component being located between the inner bearing ring and the outer bearing ring; the sleeve has a bearing cavity inside, the outer bearing ring being fixed inside the bearing cavity and having a clearance fit with the bearing cavity.

[0015] The bearings and limiting components provide support for the shaft, reduce friction between the shaft and the sleeve, and suppress radial runout and axial movement that may occur during high-speed rotation of the shaft.

[0016] In some embodiments, the bearing includes a first bearing, and the limiting component includes a first limiting component, which includes an elastic support structure and a pressure ring; the elastic support structure is sleeved on the rotating shaft, and its two ends abut against the first end and the pressure ring respectively; the pressure ring is sleeved on the rotating shaft, and the pressure ring abuts against the end face of the first bearing near the first end.

[0017] The elastic support structure can continuously apply axial preload to the first bearing, automatically compensating for bearing clearance through elastic deformation, while the pressure ring provides stable axial positioning. Thus, reliable preload and positioning of the first bearing by the first limiting assembly are achieved.

[0018] In some embodiments, the bearing includes a second bearing, and the limiting component includes a second limiting component, which includes a retaining ring and a washer; the inner ring of the second bearing is fixedly connected to the rotating shaft, and the second limiting component is sleeved on the rotating shaft; the lower end face of the second bearing abuts against the upper end face of the washer, and the lower end face of the washer abuts against the upper end face of the retaining ring. The upper end face is the end face away from the base, and the lower end face is the end face close to the base.

[0019] The spring and washer achieve axial positioning of the second bearing through a rigid contact force transmission path, which features simple structure and convenient assembly.

[0020] In some embodiments, the rotating mirror is a regular polygonal prism, and a counterweight groove is provided at each apex of the bottom of the rotating mirror; wherein, the counterweight groove is used to hold counterweight material, the counterweight material is used to adjust the mass distribution of the rotating mirror, and the bottom of the rotating mirror is the end of the rotating mirror that is close to the base.

[0021] By using the counterweight material contained within the counterweight tank, a compensating torque equal in magnitude and opposite in direction to the original eccentric mass can be generated in the circumferential direction of the rotating mirror, ensuring that the center of gravity of the rotating mirror coincides with its geometric center. Moreover, the counterweight material can be completely encapsulated within the counterweight tank, without affecting the optical working surface of the rotating mirror.

[0022] In some embodiments, the bottom of the rotating mirror is provided with an opening, and a rotating mirror groove is provided on the inner surface of the rotating mirror along the circumference of the opening. The rotating mirror groove is used to accommodate the electronic control board; wherein, the electronic control board and the rotating mirror groove form a first corner, and the bottom of the rotating mirror and the base form a second corner.

[0023] The placement of the first and second corners significantly attenuates the energy of stray light or other interfering light from the external environment before it enters the photoelectric detection module, effectively reducing interference to the photoelectric detection module.

[0024] The rotating mirror module provided in this application uses a reflective photoelectric detection module and sets the sleeve and base as two separable components, allowing the encoder disk to fully utilize the radial space inside the rotating mirror module, significantly reducing the volume of the rotating mirror module. Furthermore, by embedding the reflective photoelectric detection module within the space formed by the rotating mirror and the base, the influence of external stray light on detection accuracy is effectively reduced, ensuring the resolution and precise control of the rotating mirror module. Attached Figure Description

[0025] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0026] Figure 1 This is an exploded view of a rotating mirror module provided in an embodiment of this application;

[0027] Figure 2 This is an exploded view of the stator assembly of a rotating mirror module provided in an embodiment of this application;

[0028] Figure 3 This is an exploded view of the rotor assembly of a rotating mirror module provided in an embodiment of this application;

[0029] Figure 4 This is a cross-sectional view of a rotating mirror module provided in an embodiment of this application;

[0030] Figure 5 This is a schematic diagram of a rotor assembly provided in an embodiment of this application, showing a case where part of the cylindrical magnetic ring and the housing have been removed;

[0031] Figure 6 This is an assembly diagram of a rotor assembly and a rotating mirror provided in an embodiment of this application, showing a case where part of the rotating mirror has been removed;

[0032] Figure 7 This is an assembly diagram of a motor and a rotating mirror provided in an embodiment of this application, showing a case where part of the rotating mirror has been removed;

[0033] Figure 8 This is a schematic diagram of a rotating mirror module provided in an embodiment of this application, showing the case where part of the rotating mirror is removed;

[0034] Figure 9 This is a top view of a rotating mirror module provided in an embodiment of this application on a radial plane perpendicular to the axis of rotation;

[0035] Figure 10 This is a schematic diagram of the assembly of a rotor assembly and a sleeve provided in an embodiment of this application, showing the case where parts of the housing, sleeve, and bearing are removed.

[0036] Figure 11 This is an exploded view of a rotor assembly and sleeve provided in an embodiment of this application, showing the case where part of the housing and sleeve have been removed;

[0037] Figure 12 This is a schematic diagram of an encoding disk provided in an embodiment of this application;

[0038] Figure 13This is a schematic diagram of a rotating mirror provided in an embodiment of this application;

[0039] Figure 14 This is a schematic diagram of an assembly forming a first component AS1 provided in an embodiment of this application;

[0040] Figure 15 This is a schematic diagram of an assembly forming a second component AS2 according to an embodiment of this application;

[0041] Figure 16 This is a schematic diagram of an assembly forming a third component AS3 according to an embodiment of this application;

[0042] Figure 17 This is a schematic diagram of an assembly forming a motor AS4 provided in an embodiment of this application;

[0043] Figure 18 This is a schematic diagram of an assembly forming a rotating mirror module AS5 according to an embodiment of this application;

[0044] Figure 19 This is a schematic diagram of an electric motor provided in an embodiment of this application;

[0045] Figure 20 This is a simulation result of an optoelectronic encoder provided in an embodiment of this application;

[0046] Figure 21 This is a simulation result of another photoelectric encoder provided in the embodiments of this application.

[0047] Explanation of reference numerals in the attached figures:

[0048] Stator assembly 10; Sleeve 11; Iron core 12; Base 13; Electrical control board 14; Photoelectric detection module 15;

[0049] Bearing cavity 111; Support through hole 131; Fixing through hole 132; Operating opening 133;

[0050] Rotor assembly 20; housing 21; shaft 22; cylindrical magnetic ring 23; encoder disk 24;

[0051] Assembly hole 211; Glue overflow groove 212; First groove 213; Limiting protrusion 214; Mounting hole 241;

[0052] Rotating mirror 30; limiting through hole 301; opening 302; rotating mirror groove 303; counterweight groove 304; circular groove 305;

[0053] Bearing 40; Inner ring of bearing 41; Outer ring of bearing 42; Lubrication component 43

[0054] Limiting component 50; elastic support structure 51; pressure ring 53; snap ring 52; washer 54;

[0055] Reflective area A1; Non-reflective area A2; First end 21F; Second end 21S; Bottom of the rotating mirror 30B; Top of the rotating mirror 30T; Black coating S1; Accommodation space S2; Minimum circumcircle of the rotating mirror R1; Radial plane projection of the base R2;

[0056] First corner C1; Second corner C2; First bearing 40F; Second bearing 40S; First limiting component 50F; Second limiting component 50S; First component AS1; Second component AS2; Third component AS3; Motor AS4; Rotating mirror module AS5; Support mechanism F. Detailed Implementation

[0057] The present application will now be described in detail with reference to specific embodiments. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope and application of the present application.

[0058] It should be noted that, unless otherwise expressly specified and limited, the terms "center," "longitudinal," "lateral," "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., used in this specification to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. The terms "installed," "connected," "linked," and "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features; thus, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more; and "and / or" includes any and all combinations of one or more related listed items. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0059] In practical use, the rotating mirror module requires an optical encoder for angle detection to obtain the current operating status of the rotating mirror. One typical optical encoder works as follows: LEDs and photodetectors are placed on either side of an encoder disk that rotates with the rotor. Light emitted from the LEDs passes through a light-transmitting hole on the encoder disk and is received by the photodetector on the opposite side. As the encoder disk rotates with the motor, the light-transmitting hole and the light-blocking area alternately pass through the light path, generating pulse signals at the photodetector. Angular displacement information can be obtained by counting these pulse signals (hereinafter referred to as a through-beam optical encoder). Due to the working principle of the through-beam optical encoder, the transmitter and receiver elements must be arranged on both sides of the encoder disk, requiring sufficient installation space along the axial direction of the rotating mirror module. Simultaneously, the encoder disk itself needs a large structural dimension to ensure sufficient mechanical strength. These factors combined result in the through-beam optical encoder inevitably occupying a large space, ultimately leading to a large overall size of the rotating mirror module, making it difficult to meet the requirements for equipment miniaturization.

[0060] Furthermore, the resolution of a through-beam photoelectric encoder depends on the number of light-transmitting holes on the code disk, which is limited by the code disk diameter and manufacturing process. With a given code disk diameter, increasing the number of light-transmitting holes requires reducing the spacing between them (hereinafter referred to as code distance). However, excessively small hole spacing can lead to signal crosstalk, affecting the reliability of detection. Therefore, when the motor is running at low speeds, the number of pulses generated per unit time is relatively small, and this limitation of code distance directly results in a reduction in angle detection resolution, failing to meet the requirements for high-precision angle detection.

[0061] During the research process for this application, the applicant discovered that by adopting a reflective detection principle, the functional units for emitting detection light and receiving echo light are integrated into a photoelectric detection module located on one side of the encoder disk. This eliminates the need for separate detection elements on both sides of the encoder disk, significantly reducing the installation space in the axial direction and making the entire detection system more compact. Furthermore, the encoder disk only needs to be machined on one side for both reflective and non-reflective areas, eliminating the mechanical strength issues caused by the light-transmitting holes in the encoder disk of through-beam photoelectric encoders. Therefore, a smaller diameter encoder disk can be designed. This structural design improves space utilization and effectively reduces the overall volume of the rotating mirror module. In addition, the reflective detection principle allows for the machining of denser reflective and absorptive areas within a smaller area, achieving more detection cycles within the same size. This characteristic results in more pulse signals generated per unit time, even when the motor is running at low speeds, thus achieving higher angle detection resolution and better meeting the needs of precision control.

[0062] To fully describe the inventive concept of this application, the following detailed description, in conjunction with the accompanying drawings, describes the specific implementation of the rotating mirror module using the photoelectric encoder based on the above-described reflective detection principle.

[0063] Figure 1 This is an exploded view of a rotating mirror module provided in an embodiment of this application. Figure 1 As shown, the rotating mirror module includes: stator assembly 10, rotor assembly 20 and rotating mirror 30.

[0064] The stator assembly 10 is a general term for the components of the rotating mirror module that maintain a fixed position during operation. Correspondingly, the rotor assembly 20 is a general term for the components of the rotating mirror module that rotate relative to the stator assembly 10 during operation. The rotating mirror 30 is a component with specific reflective properties on one or more surfaces, used to change the propagation direction of the light beam. The rotating mirror 30 is connected to the rotor assembly 20 and rotates with it.

[0065] The stator assembly 10 and rotor assembly 20 constitute a motor. The motor operates according to the principle of electromagnetic induction, converting externally supplied electrical energy into kinetic energy to drive the rotor assembly 20 to rotate. The rotating mirror 30 and the rotor assembly 20 move synchronously, causing the light beam incident on the surface of the rotating mirror 30 to deflect, thereby scanning the target area. During the scanning of the target area, the photoelectric encoder inside the rotating mirror module, based on the principle of reflection detection, detects changes in the position of the encoder disk through reflected light signals to provide real-time feedback on the position information of the encoder disk, thereby achieving precise control of the motor and improving the motor resolution and the positioning accuracy of the rotating mirror.

[0066] The photoelectric encoder mainly consists of an encoder disk 24 and a photoelectric detection module 15. The encoder disk 24 is located in the rotor assembly 20, and the photoelectric detection module 15 is located in the stator assembly 10. The photoelectric detection module 15 includes a light-emitting element and a photodetector. The light-emitting element is used to emit detection light, and the photodetector is used to receive the echo light formed by the detection light reflected by the encoder disk. The light-emitting element and the photodetector are located on the same side of the encoder disk 24. (The following description is in conjunction with...) Figures 2 to 4 The specific structural components of the rotating mirror module are described in detail.

[0067] Figure 2 This is a schematic diagram of the structure of a stator assembly provided in an embodiment of this application. In some embodiments, such as Figure 2 As shown, the stator assembly 10 includes: a sleeve 11, an iron core 12, a base 13, and an electrical control board 14. The sleeve 11 is fixedly connected to the iron core 12 and the base 13 respectively, and the electrical control board 14 is fixed on the base 13.

[0068] Sleeve 11 is used to provide rotational support for the rotor assembly. The specific structural dimensions and shape of sleeve 11 can be set according to actual needs. For example, sleeve 11 can be generally cylindrical and have specific axial length and inner diameter dimensions.

[0069] The iron core 12 is used to construct a closed magnetic circuit to generate a corresponding induced magnetic field. Specifically, the iron core 12 includes a core body made of laminated silicon steel sheets and a coil wound in the winding slots of the core body.

[0070] The base 13 is used to support the entire motor structure and provide a mounting interface. The base 13 can be made of any suitable material or size structure, as long as it can provide sufficient mechanical strength and stability to ensure that the overall rigidity of the motor meets the usage requirements.

[0071] The control board 14 is a printed circuit board that integrates and sets one or more functional circuits (including but not limited to drive circuits, signal processing circuits, etc.) to realize the power supply, control, and signal processing functions of the rotating mirror module. A photoelectric detection module 15 is provided on the control board 14. The photoelectric detection module 15 includes a light-emitting device and a receiving device. The light-emitting device emits detection light of a specific wavelength, and the receiving device receives the echo light reflected back from the reflective area of ​​the encoder disk surface and converts the echo light into an electrical signal. The signal processing circuit in the control board 14 can accurately detect the rotation angle, speed, and direction of the rotating mirror module based on the electrical signal provided by the receiving device of the photoelectric detection module 15, thereby ensuring precise control of the motor.

[0072] Figure 3 This is a schematic diagram of the structure of a rotor assembly provided in an embodiment of this application. In some embodiments, such as Figure 3 As shown, the rotor assembly 20 includes: a housing 21, a rotating shaft 22, a cylindrical magnetic ring 23, and an encoder disk 24. The rotating shaft 22 is fixed to the housing 21 by an interference fit, the cylindrical magnetic ring 23 is fixedly connected to the housing 21, and the encoder disk 24 is fixedly connected to the cylindrical magnetic ring 23.

[0073] The housing 21 is used to mount and secure the rotor components. The housing can have a specific shape and size depending on the actual situation, as long as it can provide overall protection for the rotor assembly and ensure the coaxiality of the components.

[0074] The rotating shaft 22 is used to bear radial and axial loads and transmit torque. The rotating shaft 22 acts as the main shaft of the motor, supporting the rotor assembly 20 to rotate axially about the shaft. An interference fit between the rotating shaft 22 and the housing 21 ensures that there is no relative displacement between them during high-speed rotation. In one embodiment, the interference fit can be achieved by: a mounting hole 211 is provided in the center of the housing 21, and the outer diameter of the end 22A of the rotating shaft 22 is slightly larger than the inner diameter of the mounting hole 211 in the housing 21, thus achieving a reliable fixed connection between the rotating shaft 22 and the housing 21 through a press-fit method.

[0075] The cylindrical magnetic ring 23 is a cylindrical permanent magnet used to generate electromagnetic interaction with the iron core 12 in the stator assembly 10, realizing the conversion of electrical energy into mechanical energy. In some embodiments, the cylindrical magnetic ring 23 is fixed to the inside of the housing 21 by an adhesive. Adapted to the use of adhesive fixing, such as... Figure 5 As shown, the inner surface of the housing 21 is provided with a corresponding overflow groove 212 to accommodate excess adhesive.

[0076] The encoder disk 24 is a disc-shaped component. Areas on the surface of the encoder disk 24 have different optical properties, allowing it to cooperate with the photoelectric detection module 15 to achieve accurate detection of angular position information. Areas on the encoder disk 24 that can reflect detection light and form echo light are called reflective areas A1, and areas that cannot form echo light are called non-reflective areas A2. Multiple reflective and non-reflective areas are alternately arranged on the encoder disk 24. This alternating arrangement means that the reflective and non-reflective areas are distributed along the circumference of the encoder disk 24 and arranged alternately at specific intervals. For example, as... Figure 12 As shown, in the circumferential direction of the encoder disk 24, there must be a non-reflective area A2 between two adjacent reflective areas A1, and a reflective area A1 between two adjacent non-reflective areas A2, forming a regular periodic arrangement. This alternating arrangement enables the photoelectric detection module 15 to generate a stable pulse signal when the encoder disk 24 rotates, thereby accurately detecting the angular displacement of the rotor assembly.

[0077] Figure 4 This is a cross-sectional view of a rotating mirror module provided in an embodiment of this application, showing the assembly relationship between the stator assembly 10 and the rotor assembly 20. For example... Figure 4 As shown, in the rotating mirror module, the rotating shaft 22 is centrally inserted through the sleeve 11 along the axial direction of the sleeve 11, and the iron core 12 is disposed inside the cylindrical magnetic ring 23.

[0078] During the operation of the rotating mirror module, as current is applied to the coil inside the iron core 12, the iron core 12 generates a corresponding electromagnetic field. This electromagnetic field interacts with the permanent magnetic field of the cylindrical magnetic ring 23, generating a tangential electromagnetic force, which in turn forms a driving torque on the cylindrical magnetic ring 23. Under the action of the driving torque, the rotor assembly 20 rotates around the axis of the sleeve 11. Simultaneously, the rotation of the rotor assembly 20 drives the encoder disk 24 to rotate synchronously. When the reflective area A1 on the encoder disk 24 passes through the photoelectric detection module 15, the detection light emitted by the photoelectric detection module 15 is reflected to form an echo light, while when the non-reflective area A2 passes through the photoelectric detection module 15, the detection light is absorbed. This alternating change of reflection and absorption generates periodic electrical signal pulses. By counting and processing these pulses, the signal processing circuit integrated on the electronic control board 14 can obtain the precise angular position of the rotor assembly 20 in real time, thereby achieving precise control of the rotating mirror module.

[0079] The following combination Figure 5 and Figure 6 The connection relationship between the rotating mirror 30 and the rotor assembly 20 is described in detail.

[0080] Figure 6 A cross-sectional view of the rotating mirror and rotor assembly provided in an embodiment of this application. (See attached image.) Figure 6 As shown, the rotating mirror 30 is mounted outside the housing 21 of the rotor assembly 20 and rotates synchronously with the housing 21.

[0081] For ease of description, the end of housing 21 away from the base is referred to as "first end 21F", and the end of housing 21 near the base is referred to as "second end 21S"; the end of rotating mirror 30 near the base is referred to as "bottom of rotating mirror 30B", and the end of rotating mirror away from the base is referred to as "top of rotating mirror 30T".

[0082] In some embodiments, the top 30T of the rotating mirror can be fixed to part or all of the outer surface of the first end 21F of the housing 21 by adhesive bonding. Accordingly, as Figure 5 As shown, the outer surface of the first end 21F is provided with a first groove 213 for accommodating excess adhesive.

[0083] In some embodiments, to ensure synchronous rotation between the rotating mirror 30 and the housing 21, additional locating pins or similar pin structures may be added. For example, such as... Figure 6As shown, a limiting protrusion 214 is provided at the first end 21F. A limiting through hole 301 corresponding to the limiting protrusion 214 is provided at the top 30T of the rotating mirror. When the rotating mirror 30 is covered outside the housing 21 of the rotor assembly 20, the limiting protrusion 214 passes through the limiting through hole 301 to achieve circumferential positioning between the rotating mirror 30 and the housing 21, ensuring that the rotating mirror 30 will not rotate relative to the housing 21.

[0084] The following combination Figures 7 to 13 This application provides a detailed description of several embodiments for reducing external environmental interference and stray light effects.

[0085] In some embodiments, such as Figure 7 As shown, the inner surface of the rotating mirror 30 is covered with a black coating S1, and the rotor assembly 20 and the electronic control board 14 are both located within the accommodating space S2 formed by the rotating mirror 30 and the base 13. Interference or stray light from the external environment can be absorbed by the black coating on the inner surface of the rotating mirror 30 and will not be further reflected into the electronic control board 14, reducing interference to the photoelectric detection module 15 and avoiding the generation of erroneous position detection electrical signals.

[0086] In other embodiments, such as Figure 9 As shown, the smallest circumcircle of the rotating mirror 30 is covered by the radial plane projection of the base 13. The smallest circumcircle of the rotating mirror refers to the circumcircle R1 of the projection of the rotating mirror 30 along the axial direction of the rotation axis 22 onto a radial plane perpendicular to the axial direction. The radial plane projection of the base refers to the projection R2 formed by the base 13 along the same axial direction onto a radial plane. The base 13 can cover the area swept by the rotating mirror 30 during rotation, thereby further reducing the interference of stray light from the external environment on the photoelectric detection module 15.

[0087] In some other embodiments, such as Figure 13 As shown, an opening 302 is provided at the bottom of the rotating mirror 30, and a rotating mirror groove 303 is provided on the inner surface of the rotating mirror along the circumference of the opening 302. The edge of the electronic control board 14 is accommodated in the space formed by the rotating mirror groove 303. Figure 8 As shown, a first corner C1 is formed between the electronic control board 14 and the rotating mirror groove 303. Simultaneously, the bottom of the rotating mirror 30 cooperates with the base 13 to form a second corner C2. Stray light or other interfering light from the external environment experiences significant energy attenuation after passing through the first corner C1 and the second corner C2, thus weakening the external light entering the photoelectric detection module 15. This structural arrangement effectively reduces the interference of external light on the photoelectric detection module 15.

[0088] The rotating mirror used in the rotating mirror module can be selected with a suitable shape according to the actual needs. For example, the accompanying drawings of this application show a rotating mirror 30 that is a regular quadrilateral prism. In some embodiments, other regular polygonal prisms, such as a rotating mirror that is a regular triangular prism, can also be used.

[0089] In some embodiments, such as Figure 13 As shown, when using a rotating mirror 30 in the shape of a regular polygonal prism, a counterweight sink 304 for accommodating counterweight material is provided at each apex of the bottom 30B of the rotating mirror.

[0090] Due to factors such as processing errors and uneven material density, the mass distribution of the rotating mirror 30 will inevitably be uneven, meaning its center of gravity may deviate from the axis of rotation. This eccentricity can cause unnecessary centrifugal force during high-speed rotation, affecting stable operation. To ensure stable operation as much as possible, by filling the specific counterweight groove 304 with counterweight material, a compensating torque equal in magnitude and opposite in direction to the original eccentric mass can be formed in the circumferential direction of the rotating mirror 30. This makes the center of gravity of the rotating mirror 30 coincide with its geometric center (or makes the center of gravity fall on the axis of rotation), thereby ensuring that the rotating mirror 30 maintains a stable operating state during high-speed rotation. Moreover, this structural arrangement allows the counterweight material to be completely encapsulated within the counterweight groove 304 at the bottom corner, without affecting the optical working surface of the rotating mirror.

[0091] In some embodiments, please continue reading Figure 6 A circular recess 305 for accommodating counterweight material is provided at the top 30T of the rotating mirror. The center of the circular recess 305 is located on the axis of the rotating shaft 22. The circular recess 305 is a reserved position for dynamic balancing. By controlling the weight and position of the counterweight material, dynamic balance of the rotating mirror during rotation can be achieved, reducing vibration and eccentricity during high-speed rotation. For example, a mass can be loaded at any point on a circle, making the adjustment process simple and direct.

[0092] In other embodiments, each of the top corners of the top 30T of the rotating mirror is provided with a corner groove for accommodating counterweight materials, which facilitates subsequent motor calibration and improves the production efficiency of dynamic balancing debugging.

[0093] In the rotating mirror module, one or more additional auxiliary structures can be added to provide necessary support for the rotating shaft 22, reduce the friction between the rotating shaft 22 and the sleeve 11, and suppress the radial runout and axial movement that may occur during the high-speed rotation of the rotating shaft 22, so as to ensure that the rotational movement of the rotor assembly is more stable, accurate and reliable.

[0094] The following combination Figure 10 and Figure 11This application provides a detailed description of various embodiments of the auxiliary structure provided, in order to fully illustrate the structural features and working principle of the auxiliary structure.

[0095] Figure 10 This is a schematic diagram of a rotating shaft and sleeve provided in an embodiment of this application. Figure 10 As shown, the rotating mirror module also includes a bearing 40 and a limiting component 50.

[0096] The bearing 40 is assembled between the shaft 22 and the sleeve 11 to bear radial loads and achieve low-friction relative rotation between the two.

[0097] The limiting component 50 is used to control the axial position of the bearing 40. The limiting component 50 is connected to the bearing 40. By applying appropriate axial preload to the bearing 40, the internal clearance of the bearing is eliminated, thereby improving the radial stiffness and rotational accuracy of the bearing.

[0098] Figure 11 This is an exploded view of a rotating shaft and sleeve provided in an embodiment of this application. Figure 11 As shown, the sleeve 11 has a bearing cavity 111 inside to accommodate the bearing 40. Figure 10 As shown, each bearing 40 includes an inner bearing ring 41, an outer bearing ring 42, and a lubrication component 43. The inner bearing ring 41 is interference-fitted with the rotating shaft 22, and the outer bearing ring 42 is clearance-fitted with the bearing cavity 111. This fit ensures the positioning accuracy of the bearing and facilitates its assembly and replacement.

[0099] In some embodiments, the outer ring 42 of the bearing is bonded and fixed to the bearing cavity 111. In other embodiments, considering factors such as assembly difficulty, maintenance convenience, and reliability, other suitable types of fixing methods such as snap ring fixing or end cap clamping can be used.

[0100] In some embodiments, the lubrication component 43 is located between the inner ring 41 and the outer ring 42 of the bearing to reduce friction between them. Specifically, the lubrication component 43 includes, but is not limited to, rolling elements, cages, or lubricating oil.

[0101] For example, Figure 10 The illustration shows a configuration with two bearings 40. However, those skilled in the art will understand that the number of bearings can be increased or decreased as needed, and is not limited to this configuration. Figure 10 The two bearings shown are referred to as "first bearing 40F" and "second bearing 40S" for ease of explanation. Correspondingly, the limiting components used to restrict the axial movement of the first bearing are referred to as "first limiting component 50F" and "second limiting component 50S".

[0102] The following combination Figure 11 Taking the first bearing 40F and the second bearing 40S as examples, this paper describes in detail the connection relationship between the bearings and their corresponding limiting components, as well as the limiting design concept. Figure 11 In this context, "upper end face" refers to the end face furthest from the base, while "lower end face" refers to the end face closest to the base.

[0103] In some embodiments, such as Figure 11 As shown, the first limiting component 50F includes an elastic support structure 51 and a pressure ring 53. The elastic support structure 51 is sleeved on the rotating shaft 22, and its two ends abut against the first end and the pressure ring 53, respectively. The pressure ring 53 is sleeved on the rotating shaft 22, and the pressure ring 53 abuts against the end face of the first bearing 40F near the first end.

[0104] This design allows the elastic support structure 51 to indirectly abut against the inner ring 41 of the first bearing 40F through the pressure ring 53, continuously applying axial preload to the first bearing 40F. The bearing clearance is automatically compensated through elastic deformation, while the pressure ring 53 provides stable axial positioning. The two work together to achieve reliable preload and limit of the bearing.

[0105] In other embodiments, please continue to refer to Figure 11 The second limiting component 50S includes a retaining ring 52 and a washer 54. The inner ring 41 of the second bearing 40S is fixedly connected to the rotating shaft 22. The retaining ring 52 is sleeved on the rotating shaft 22. The upper end face of the washer 54 abuts against the lower end face of the second bearing 40S. The lower end face of the washer 54 abuts against the upper end face of the retaining ring 52. Thus, through a rigid contact force transmission path, the axial limiting of the second bearing 40S is achieved. This second limiting component has the characteristics of simple structure, convenient assembly, and the ability to provide a stable axial positioning effect.

[0106] It should be noted that the first limiting component 50F and the second limiting component 50S described above respectively demonstrate a pre-tightening limiting method based on an elastic support structure and a rigid limiting method based on a retaining spring. The appropriate limiting method can be selected based on the specific needs of the actual application scenario (such as assembly space, pre-tightening force requirements, assembly convenience, etc.), and is not limited to the scenario described in the embodiments of this application.

[0107] During the assembly of the rotating mirror module, the stator assembly 10 and rotor assembly 20 are typically assembled separately before the rotor assembly 20 is assembled onto the stator assembly 10. In this assembly method, because the stator assembly 10 needs to be inserted entirely from the bottom of the rotor assembly 20, the inner diameter of the mounting hole at the center of the encoder disk 24 at the bottom of the rotor assembly 20 must be larger than the outer diameter of the iron core 12 of the stator assembly 10; otherwise, assembly cannot be completed. This structural constraint necessitates a larger inner diameter for the mounting hole of the encoder disk 24, which in turn affects the overall dimensions of the encoder disk 24 and the motor.

[0108] During the research of this application, the applicant discovered that by setting the sleeve 11 and the base 13 as two separable parts, during assembly, the encoder disk 24 can be first fixed to the cylindrical magnetic ring 23 in the rotor assembly 20 through the sleeve 11, and then the base 13 (and the stator assembly fixed on the base 13) can be assembled with the sleeve 11. In this way, the mounting hole of the encoder disk 24 does not need to consider the size limitation of the iron core 12, and only needs to ensure that the sleeve 11 can pass smoothly through the mounting hole of the encoder disk 24, which creates favorable conditions for the overall miniaturization of the rotating mirror module.

[0109] To fully describe the inventive concept of this application and demonstrate the specific advantages and principles of using separate components for the sleeve 11 and the base 13, the following will be combined with... Figures 12 to 17 The encoder disk and its rotating mirror module with this split structure are described in detail.

[0110] Figure 12 This is a schematic diagram of the encoding disk 24 provided in an embodiment of this application. Figure 12 As shown, the encoder disk 24 is an annular component with a circular mounting hole 241 at its center.

[0111] The lower limit of the size of the mounting hole 241 is that the projection of the mounting hole 241 along the axial direction of the rotating shaft onto the horizontal plane covers the projection of the sleeve 11 along the axial direction onto the horizontal plane, ensuring that the sleeve 11 can pass through smoothly. The upper limit of the size of the mounting hole 241 can be set to: the diameter of the mounting hole 241 is smaller than the inner diameter of the cylindrical magnetic ring, thereby reducing the size of the motor. It is understood that the smaller the size of the circular mounting hole 241, the better the effect of reducing the motor size. Technicians can set specific size values ​​according to actual needs, as long as they are not less than the aforementioned lower limit.

[0112] During motor assembly, such as Figure 14 As shown, firstly, the iron core 12 is assembled and fixed onto the sleeve 11 to form the first component AS1, and, as... Figure 15 As shown, the rotating shaft 22 and the cylindrical magnetic ring 23 are assembled and fixed onto the housing 21 to form the second component AS2. Then, as... Figure 16As shown, align the rotating shaft 22 with the insertion sleeve 11, assembling the first component AS1 into the second component AS2 (at this time, the iron core 12 is surrounded by the cylindrical magnetic ring 23). Then, pass the encoder disk 24 through the sleeve 11 and assemble and fix it onto the cylindrical magnetic ring 23, forming the third component AS3. Finally, as shown... Figure 17 As shown, the control board 14 is secured to the base 13 using screws or other locking accessories, and the base 13 is then assembled and secured to the sleeve 11, resulting in a complete motor AS4. It should be noted that the above motor assembly process is for illustrative purposes only and is not intended to limit the specific motor components and their assembly sequence. As long as the third component AS3 is formed later than the second component AS2 (i.e., the encoder disk 24 is fixed to the cylindrical magnetic ring 23 after the iron core 12 is surrounded by the cylindrical magnetic ring 23), the effect of lowering the lower limit of the mounting hole 241 size can be achieved. After completing the assembly of the motor AS5, as... Figure 18 As shown, it is also necessary to further fix the rotating mirror 30 cover onto the housing 21 to obtain the final rotating mirror module AS5.

[0113] In some embodiments, such as Figure 19 As shown, the base 13 has one or more support through holes 131.

[0114] Applying sufficient holding pressure during the assembly of the rotating mirror 30 can reduce the installation tilt angle of the rotating mirror 30, but excessive holding pressure can cause wear on the bearings between the stator assembly 10 and the rotor assembly 20. To minimize the negative impact of the holding pressure and ensure a sufficiently strong holding pressure can be used during the assembly of the rotating mirror, a removable support mechanism F (e.g., a support rod or similar rod-like object) abuts against the housing 21 through the support through-hole 131 during the assembly of the rotating mirror 30, thereby providing support force. Thus, most of the holding pressure applied during the assembly of the rotating mirror 30 is transferred to the support mechanism F and does not directly act on the bearings 40 between the stator assembly 10 and the rotor assembly 20, effectively avoiding the negative impact of the holding pressure. Therefore, a stronger holding pressure can be safely used for the assembly of the rotating mirror 30.

[0115] To verify the reliability of the rotating mirror module provided in the embodiments of this application, this application further conducted optical performance simulation experiments on the photoelectric detection module provided in the above embodiments. Figure 20 and Figure 21 These are the results of optical performance simulation experiments for two photoelectric detection modules. In the optical performance simulation experiments, the incident light source was set as an ideal parallel beam to simulate solar radiation conditions, and the light source emission power was 1W.

[0116] like Figure 20 and Figure 21As shown, under normal operating conditions of the rotating mirror module, the photoelectric detection module can stably receive optical signals. The received energies of the two photoelectric detection modules are 2.46×10⁻¹² W and 1.76×10⁻¹¹ W, respectively.

[0117] The noise level of the photoelectric detection module is less than 1×10 -6 W indicates that the received signal has a sufficient signal-to-noise ratio margin (signal strength is much lower than the noise threshold by about 5-6 orders of magnitude), which shows that the photoelectric detection module has good anti-interference ability and signal detection reliability. This verifies that the rotating mirror module provided in the above embodiment can provide a stable and reliable position feedback signal in the actual working environment.

[0118] Based on the rotating mirror module provided in the above embodiments, this application further provides a lidar. Please continue reading. Figure 19 The base 13 of the rotating mirror module can also be provided with several fixing through holes 132 and operation openings 133.

[0119] The rotating mirror module can be fixed to the lidar using screws or similar locking accessories through the fixing through-hole 132 on the base 13. The operating opening 133 on the base 13 allows for the welding of the power supply wires to the iron core 12 and dynamic balancing adjustments, ensuring reliable and stable operation of the rotating mirror module.

[0120] It should be noted that one or more structural components disclosed in the above embodiments may be reduced or added as needed to provide corresponding functions or technical effects. The above structural components are not mutually exclusive or related and can be arbitrarily combined to form multiple different embodiments.

[0121] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. Those skilled in the art can make various modifications and improvements without departing from the concept of this application, and all of these fall within the scope of protection of this application.

Claims

1. A rotating mirror module, characterized in that, The system includes a stator assembly, a rotor assembly, and a rotating mirror. The stator assembly includes a sleeve, an iron core, a base, and an electronic control board. The rotor assembly includes a housing, a rotating shaft, a cylindrical magnetic ring, and an encoder disk. The sleeve is fixedly connected to the iron core and the base respectively. The electronic control board is fixed on the base. The electronic control board is provided with a photoelectric detection module. The photoelectric detection module includes a light-emitting element and a photodetector. The light-emitting element is used to emit detection light, and the photodetector is used to receive the echo light formed by the detection light reflected by the encoder disk. The light-emitting element and the photodetector are arranged on the same side of the encoder disk. The housing is fixedly connected to the rotating mirror, the rotating shaft is interference-fitted to the housing, the cylindrical magnetic ring is fixedly connected to the housing, the encoder disk is fixedly connected to the cylindrical magnetic ring, and the encoder disk has multiple alternately arranged reflective areas and multiple non-reflective areas; The rotating shaft is centrally inserted through the sleeve along the axial direction of the sleeve, and the iron core is disposed inside the cylindrical magnetic ring.

2. The rotating mirror module according to claim 1, characterized in that, The rotating mirror cover is disposed outside the housing, and the housing includes a first end and a second end, wherein the first end is the end of the housing away from the base, and the second end is the end of the housing close to the base; A first groove is formed on the outer surface of the first end, and the top of the rotating mirror is bonded to at least a portion of the outer surface of the first end; The first end is provided with a limiting protrusion, and the top of the rotating mirror is provided with a limiting through hole corresponding to the limiting protrusion, and the limiting protrusion passes through the limiting through hole.

3. The rotating mirror module according to claim 1, characterized in that, The inner surface of the rotating mirror is covered with a black coating, and the rotor assembly and the electronic control board are located within the accommodating space formed by the rotating mirror and the base.

4. The rotating mirror module according to claim 3, characterized in that, The smallest circumcircle of the rotating mirror is covered by the radial plane projection of the base; Wherein, the smallest circumcircle of the rotating mirror is the circumcircle of the projection of the rotating mirror along the axial direction of the rotating axis onto a radial plane perpendicular to the axial direction, and the radial plane projection of the base is the projection of the base along the axial direction onto the radial plane.

5. The rotating mirror module according to claim 1, characterized in that, The encoder disk is a ring-shaped component with a circular mounting hole at its center. The projection of the mounting hole along the axial direction of the rotating shaft onto the horizontal plane covers the projection of the sleeve along the axial direction onto the horizontal plane. The diameter of the mounting hole is smaller than the inner diameter of the cylindrical magnetic ring.

6. The rotating mirror module according to claim 2, characterized in that, It also includes a bearing and a limiting assembly, the limiting assembly being used to limit the axial movement of the bearing; Each of the bearings includes an inner bearing ring, an outer bearing ring, and a lubrication component located between the inner bearing ring and the outer bearing ring; The sleeve has a bearing cavity inside, and the outer ring of the bearing is fixed inside the bearing cavity and has a clearance fit with the bearing cavity.

7. The rotating mirror module according to claim 6, characterized in that, The bearing includes a first bearing, and the limiting component includes a first limiting component, which includes an elastic support structure and a pressure ring; The elastic support structure is sleeved on the rotating shaft, and the two ends of the elastic support structure abut against the first end of the housing and the pressure ring, respectively. The pressure ring is sleeved on the rotating shaft, and the pressure ring abuts against the end face of the first bearing near the first end.

8. The rotating mirror module according to claim 6, characterized in that, The bearing includes a second bearing, and the limiting component includes a second limiting component, which includes a retaining ring and a washer; The inner ring of the second bearing is fixedly connected to the rotating shaft, and the second limiting component is sleeved on the rotating shaft; The lower end face of the second bearing abuts against the upper end face of the washer, and the lower end face of the washer abuts against the upper end face of the snap ring, wherein the upper end face is the end face away from the base, and the lower end face is the end face close to the base.

9. The rotating mirror module according to claim 1, characterized in that, The rotating mirror is a regular polygonal prism, and a counterweight groove is provided at each apex of the bottom of the rotating mirror; The counterweight trough is used to hold counterweight material, which is used to adjust the mass distribution of the rotating mirror. The bottom of the rotating mirror is the end of the rotating mirror that is close to the base.

10. The rotating mirror module according to claim 9, characterized in that, The bottom of the rotating mirror is provided with an opening, and a rotating mirror groove is provided on the inner surface of the rotating mirror along the circumference of the opening. The rotating mirror groove is used to accommodate the electronic control board. The electronic control board forms a first corner with the rotating mirror groove, and the bottom of the rotating mirror forms a second corner with the base.

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