Area coverage scanning laser radar driving device

Abstract

The utility model discloses an area coverage scanning laser radar driving device, relates to the laser ranging radar and optical scanning field, the area coverage scanning laser radar driving device comprises a pedestal, a driving structure and a control panel, the pedestal is used for being installed on a sweeping robot, the driving structure comprises a stator assembly, a rotor assembly and a rotating shaft, the rotating shaft is rotatably installed on the base, the stator assembly comprises a first circuit board arranged on the base, a plurality of copper foil layers are arranged on the first circuit board, coils are etched on the copper foil layers, the winding directions of the coils are the same, the rotor assembly comprises a plurality of permanent magnets, and the permanent magnets are arranged on the peripheral side of the rotating shaft in the circumferential direction of the rotating shaft. The control panel is installed at the top end of the rotating shaft, and a laser transmitter is arranged at the top of the control panel and used for scanning the surrounding environment. The stator coil is directly etched on the fixed copper foil layer, and the permanent magnet is fixed on the rotating shaft, so that a highly concentrated structure is formed, and the size of the laser radar is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of laser ranging radar and optical scanning, and in particular to a driving device for an area coverage scanning laser radar. Background Art

[0002] Now that intelligent machines are becoming more and more advanced, many families have begun to use sweeping robots to automatically clean up garbage on the ground. When sweeping robots automatically clean the ground, they need to scan the environment in which they are located, so as to automatically avoid obstacles. The scanning environment is mostly achieved through laser radar. The driving device makes the laser radar rotate a circle to scan the environment around the sweeping robot, and then determine what obstacles there are in that direction that need to be avoided.

[0003] The laser radar drive device used in existing sweeping robots is often a DC brushed motor, which requires a pulley to drive the laser emitter to rotate. This makes the entire laser radar relatively large, especially too high. As a result, the sweeping robot cannot enter under some sofas or tables and chairs for cleaning, and users need to clean them themselves. Utility Model Content

[0004] The main purpose of this utility model is to propose an area coverage scanning laser radar driving device, which aims to reduce the size of the laser radar and facilitate the sweeping robot to enter the bottom of the sofa or table and chair for cleaning.

[0005] To achieve the above-mentioned purpose, the area coverage scanning laser radar driving device proposed in the present invention includes:

[0006] A base, used for installation on the sweeping robot;

[0007] A drive structure comprising a stator assembly, a rotor assembly, and a rotating shaft, wherein the rotating shaft is rotatably mounted on the base, the stator assembly comprising a first circuit board disposed on the base, wherein a plurality of copper foil layers are disposed on the first circuit board, wherein each of the copper foil layers is etched with a coil, and wherein each of the coils has the same winding direction, the rotor assembly comprising a plurality of permanent magnets, wherein the plurality of permanent magnets are arranged circumferentially along the rotating shaft and disposed on an outer peripheral side of the rotating shaft; and

[0008] A control board is installed on the top of the rotating shaft. A laser emitter is provided on the top of the control board for scanning the surrounding environment.

[0009] Preferably, the coil head and tail of each copper foil layer are provided with a soldering pad, the soldering pad is provided with a via hole, and the via holes of each soldering pad are coaxially aligned in the vertical direction.

[0010] Preferably, a conductive layer is provided on the hole wall of the via hole, and the conductive layer is made of copper.

[0011] Preferably, the pads on each copper foil layer are distributed axially symmetrically with the rotation axis as the center.

[0012] Preferably, a rotor disk is provided on the rotating shaft, and the rotor disk is located on the top of the copper foil layer. The rotor disk is an annular structure, and the multiple permanent magnets are embedded on the top of the rotor disk and arranged at equal intervals along the circumferential direction.

[0013] Preferably, a detection device is provided on the rotating shaft, and the detection device is used to detect changes in the magnetic field to obtain angular position information of the rotating shaft.

[0014] Preferably, the detection device includes at least one position sensor for detecting changes in the magnetic field to obtain position information.

[0015] Preferably, a protective shell is provided on the base, and the protective shell covers the laser emitter.

[0016] Preferably, a mounting structure is provided on the base, and the mounting structure includes a connector, and the connector is snapped into the protective shell to limit the protective shell from being separated from the base.

[0017] Preferably, the mounting structure further comprises a screw connection member, which passes through the side wall of the protective shell and is threadedly connected to the plug-in member to fix the protective shell.

[0018] In the technical solution provided by the present invention, the driving structure includes a stator assembly, a rotor assembly and a rotating shaft, the rotating shaft is rotatably installed on the base, the stator assembly includes a first circuit board provided on the base, a plurality of copper foil layers are provided on the first circuit board, each of the copper foil layers is etched with a coil, and the winding direction of each coil is the same, the rotor assembly includes a plurality of permanent magnets, and the plurality of permanent magnets are arranged along the circumference of the rotating shaft on the outer peripheral side of the rotating shaft, the stator coil is directly etched on the fixed copper foil layer, and the permanent magnet is fixed on the rotating shaft, forming a highly centralized structure, thereby reducing the size of the entire laser radar, so that the sweeping machine can enter narrower areas for cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0020] Figure 1This is an exploded diagram of an embodiment of the area coverage scanning laser radar driving device provided by the present invention;

[0021] Figure 2 for Figure 1 Schematic diagram of the connection structure between the stator assembly and the rotor assembly;

[0022] Figure 3 for Figure 2 Schematic diagram of the structure of the middle copper foil layer;

[0023] Figure 4 for Figure 1 Schematic diagram of the connection structure between the middle base and the protective shell;

[0024] Figure 5 for Figure 4 A magnified schematic diagram of part A in the figure.

[0025] Description of Figure Numbers:

[0026] 100. Area coverage scanning laser radar drive device; 1. Base; 2. Rotating shaft; 3. Rotor assembly; 31. Rotor disk; 32. Permanent magnet; 4. Stator assembly; 41. First circuit board; 42. Copper foil layer; 5. Control board; 6. Laser emitter; 7. Protective shell; 8. Mounting structure; 81. Connector; 82. Screw connector; 9. Detection device; 10. Solder pad; 11. Via.

[0027] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), such directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0031] The utility model provides a driving device 100 for an area coverage scanning laser radar. Figures 1 to 5 This is an embodiment of the area coverage scanning laser radar driving device 100 provided by the present invention.

[0032] Please also refer to Figures 1 to 3 The area coverage scanning laser radar driving device 100 includes a base 1, a driving structure and a control board 5, wherein the base 1 is used to be installed on a sweeping robot, the driving structure includes a stator assembly 4, a rotor assembly 3 and a rotating shaft 2, the rotating shaft 2 is rotatably installed on the base 1, the stator assembly 4 includes a first circuit board 41 provided on the base 1, a plurality of copper foil layers 42 are provided on the first circuit board 41, each copper foil layer 42 is etched with a coil, and each coil has the same winding direction, the rotor assembly 3 includes a plurality of permanent magnets 32, and the plurality of permanent magnets 32 are arranged along the circumference of the rotating shaft 2 on the outer peripheral side of the rotating shaft 2, the control board 5 is installed at the top of the rotating shaft 2, and a laser emitter 6 is provided on the top of the control board 5 for scanning the surrounding environment.

[0033] The stator assembly 4, rotor assembly 3, and shaft 2 actually form a miniature PCB motor. The stator assembly 4 is primarily composed of coils etched on a copper foil layer 42. The types of coils etched on the copper foil layer 42 include planar spiral coils and racetrack-shaped coils. The magnetic field strength is enhanced by increasing the number of copper foil layers 42. Multiple copper foil layers 42 are stacked on the first circuit board 41 to form a complete winding circuit. When the control circuit on the first circuit board 41 is passed through a current that changes according to a specific sequence, these coils generate a rotating magnetic field. The copper foil layer 42 is provided with an insulating substrate, such as a flexible polyimide substrate. An aluminum substrate can also be used to improve heat dissipation efficiency. The stator assembly 4 is primarily composed of multiple permanent magnets 32, and these permanent magnets 32 are arranged on the outer periphery of the shaft 2 along the axial direction of the shaft 2. The permanent magnets 32 are mostly fan-shaped or annular in shape to facilitate matching with the magnetic field distribution of the PCB coils. The rotating magnetic field generated by the stator coils exerts a Lorentz force on these permanent magnets, pushing or pulling the permanent magnets 32 to follow the direction of the magnetic field, thereby driving the shaft 2 to rotate.

[0034] The laser emitter 6 emits a low-power laser pulse beam of a specific wavelength that is invisible to the human eye, usually near-infrared light, such as 905nm or 1550nm. There is also a laser driving circuit for accurately controlling the emission timing and power of the laser pulse. The photodetector is usually integrated next to or on the board of the laser module to receive the weak light signal reflected back after the laser beam encounters an object. The receiving signal processing circuit is used to amplify, aluminum foil and process the received light signal. The ranging circuit calculates the time difference between the emission of the laser pulse beam and the reception of the reflected light signal, multiplying it by the speed of light and dividing it by 2 to calculate the distance to the surface of the object in front.

[0035] The main control system sends a control signal to the first circuit board 41 fixed on the base 1 through the connector. The driving circuit of the first circuit board 41 excites the coil etched on the copper foil layer 42 according to a specific timing and phase. When the coil is energized, a changing magnetic field is generated. This changing magnetic field interacts with the array of permanent magnets 32 fixed on the rotating shaft 2. The magnetic force acts on the permanent magnets 32 to form a torque, driving the rotating shaft 2 to start rotating. The speed and direction of the rotating shaft 2 are precisely adjusted by controlling the sequence of the coil current. While rotating, the laser emitter 6 is driven to rotate together through the control board 5 on the top. During the rotation process, the laser emitter 6 on the control board 5 continuously emits laser pulses. This high-speed rotating laser beam forms a 360-degree scanning sector in the horizontal direction. After the laser beam hits the surface of the obstacle, part of the light will be reflected The reflected light is emitted back and received by the photoelectric detector on the control board 5. The distance to the obstacle is calculated. In order to ensure that the photoelectric detector can receive the light reflected back after being emitted by the laser transmitter 6 in any direction, the receiving device of the photoelectric detector needs to be set in a circle around the laser transmitter 6 to ensure that the light reflected back from any direction can be received by the photoelectric detector. At the same time, due to the change in the receiving direction, there is a certain error in the calculated distance between the sweeping robot and the obstacle. Therefore, the sweeping robot will automatically turn after a certain distance from the obstacle to avoid the obstacle. Among them, the control board 5 is only responsible for controlling the laser transmitter 6. The power supply equipment of the stator assembly 4 and the rotor assembly 3 in the drive structure is arranged inside the sweeping robot, and its power supply equipment is also controlled by the control device inside the sweeping robot.

[0036] Therefore, in the technical solution provided by the present invention, the driving structure includes a stator assembly 4, a rotor assembly 3 and a rotating shaft 2, the rotating shaft 2 is rotatably mounted on the base 1, the stator assembly 4 includes a first circuit board 41 provided on the base 1, and a plurality of copper foil layers 42 are provided on the first circuit board 41, each copper foil layer 42 is etched with a coil, and the winding direction of each coil is the same, the rotor assembly 3 includes a plurality of permanent magnets 32, and the plurality of permanent magnets 32 are arranged along the circumference of the rotating shaft 2 on the outer peripheral side of the rotating shaft 2, the stator coil is directly etched on the fixed copper foil layer 42, and the permanent magnet 32 ​​is fixed on the rotating shaft 2, forming a highly centralized structure, thereby reducing the size of the entire laser radar, so that the sweeping machine can enter narrower areas for cleaning.

[0037] In order to connect the coils on different copper foil layers 42 in series or in parallel, a corresponding structure needs to be set up. Specifically, in the embodiment of the present invention, the head end and the tail end of the coil of each copper foil layer 42 are provided with a soldering pad 10, and a via 11 is opened on the soldering pad 10, and the via 11 of each soldering pad 10 is coaxially aligned in the vertical direction.

[0038] The soldering pad 10 can provide physical support for the component pins, and firmly fix the components on the circuit board through welding to prevent the components from falling off or loosening. Secondly, the soldering pad 10 acts as a bridge to connect the component pins with the copper foil traces inside the PCB to form a complete circuit path. The larger area of ​​the soldering pad 10 can help dissipate the heat generated when the component is working, improve the stability and life of the component, and the via 11 allows the copper foil layers 42 to achieve interlayer conduction with the shortest path, avoiding additional traces to reduce signal loss and interference, thereby saving a lot of space, making the entire driving structure more compact, and further reducing the size of the lidar.

[0039] Since the pad 10 is mostly made of insulating material, the inner wall of the via 11 formed therein is also insulating, preventing the two adjacent copper foil layers 42 from being connected in series or parallel. Therefore, a structure capable of passing current is required. Specifically, in the embodiment of the present invention, a conductive layer made of copper is provided on the wall of the via 11. A conductive path is formed by plating a layer of copper on the wall of the via 11, thereby electrically connecting the coils on the upper and lower copper foil layers 42.

[0040] Furthermore, the pads 10 on each copper foil layer 42 are distributed axially symmetrically with the rotation axis 2 as the center.

[0041] If the coil is a planar spiral coil, the pad 10 is usually located at the starting point and end point of the spiral and is symmetrically distributed on both sides of the rotating shaft 2 to ensure that the coil current path is symmetrical about the rotating shaft 2 to avoid magnetic field deviation. If it is a runway-shaped coil, the pad 10 may be located at both ends of the coil and symmetrically distributed along the axis of the rotating shaft 2 to make the magnetic field evenly coupled in the axial or radial direction. The symmetrical layout can offset the radial electromagnetic force generated when the coil is energized, reduce the risk of rotor eccentricity or vibration (especially in high-speed rotation scenarios), and improve mechanical stability. At the same time, the symmetrical setting facilitates mass production and reduces production costs, and also facilitates the simplification of the structure and reduction of the size of the lidar.

[0042] The permanent magnet 32 ​​can be installed by opening a groove on the circumferential side of the rotating shaft 2 and embedding it into the groove, but the one-piece annular permanent magnet 32 ​​cannot be embedded in it, so a more suitable structure that does not expand the size of the laser radar is needed. Specifically, in the technical solution of the present invention, a rotor disk 31 is provided on the rotating shaft 2, and the rotor disk 31 is located on the top of the copper foil layer 42. The rotor disk 31 is an annular structure, and multiple permanent magnets 32 are embedded on the top of the rotor disk 31 and are arranged at equal intervals along the circumferential direction.

[0043] A thin annular rotor disk 31 is fixed to the outer circumference of the rotating shaft 2, and then the permanent magnets 32 are installed on the rotor disk 31 in a set order. A certain gap is left between the rotor disk 31 and the copper foil layer 42 to facilitate the permanent magnets 32 to drive the rotating shaft 2 to rotate through the rotor disk 31.

[0044] In the PCB coil structure, the magnetic field generated by the coil needs to precisely match the magnetic field of the rotor permanent magnet 32 ​​. Specifically, a detection device 9 is provided on the rotating shaft 2 , which is used to detect changes in the magnetic field to obtain angular position information of the rotating shaft 2 .

[0045] Through angular position information, the controller can synchronize the current direction and magnitude of the multi-layer coils to avoid mutual cancellation of magnetic fields and maximize the efficiency of electromagnetic force output. At the same time, through abnormal fluctuations in the angular position signal, it can detect whether the rotating shaft 2 is stuck, whether the transmission components are loose, or whether the permanent magnet 32 ​​is detached. In extreme cases (such as loss of position feedback), the system can trigger a protection mechanism (such as power off and shutdown) to avoid equipment damage.

[0046] Furthermore, the detection device 9 includes at least one position sensor for detecting changes in the magnetic field to obtain position information.

[0047] There are many types of position sensors. For example, the integrated Hall sensor is usually installed in the sensing area reserved on the first circuit board 41. This area is generally close to the component that needs to detect the change of the magnetic field. In this application, it should be installed at the end of the rotating shaft 2 close to the permanent magnet 32. Another example is the optical encoder, which consists of an LED light source, a marking disk attached to the motor shaft and a photodetector. The LED light source and the photodetector are usually installed on the first circuit board 41 and are arranged relative to each other. The marking disk is installed on the rotating shaft 2. As the rotating shaft 2 rotates, the opaque and transparent areas on the marking disk will alternately block the light. The photodetector obtains the position information of the motor shaft by detecting the change in light.

[0048] Please also refer to Figures 4 and 5 The laser emitter 6 needs to be protected during use of the sweeping robot to prevent it from being damaged by direct collisions. Specifically, a protective shell 7 is provided on the base 1, and the protective shell 7 covers the laser emitter 6. A shell that can completely cover the laser emitter 6 protects it from being directly damaged by collisions. At the same time, in order to ensure the use of the laser emitter 6, the protective cover needs to be made of a material that does not hinder the penetration of the laser pulse beam, such as acrylic resin, cycloolefin polymer, etc.

[0049] Furthermore, the base 1 is provided with a mounting structure 8, which includes a connector 81. The connector 81 is snapped into the protective shell 7 to prevent the protective shell 7 from detaching from the base 1. The protective shell 7 needs to replace the laser emitter 6 to withstand impact, so the protective shell 7 is more susceptible to damage. To ensure the long-term use of the laser emitter 6, the protective shell 7 needs to be replaced in a timely manner after being damaged. Therefore, the protective shell 7 needs to be able to be removed from the base 1 at any time and a new, undamaged protective shell 7 installed.

[0050] Furthermore, the mounting structure 8 further includes a screw connector 82, which penetrates the side wall of the protective shell 7 and is threadedly connected to the plug connector 81 to fix the protective shell 7. The screw connector 82 locks the plug connector 81 to the base 1, preventing the protective shell 7 from being directly separated from the base 1 after being hit too violently during the movement of the sweeping robot, thereby losing the protection of the laser emitter 6. At the same time, the screw connector 82 also facilitates the user to disassemble and replace the protective shell 7. The screw connector 82 is more commonly a screw, which fixes the plug connector 81 through the threaded hole to lock the protective shell 7.

[0051] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made based on the contents of the present invention specification and drawings, or direct / indirect application in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A driving device for an area coverage scanning laser radar, characterized in that: include: A base, used for installation on the sweeping robot; A drive structure comprising a stator assembly, a rotor assembly, and a rotating shaft, wherein the rotating shaft is rotatably mounted on the base, the stator assembly comprising a first circuit board disposed on the base, wherein a plurality of copper foil layers are disposed on the first circuit board, wherein each of the copper foil layers is etched with a coil, and wherein each of the coils has the same winding direction, the rotor assembly comprising a plurality of permanent magnets, wherein the plurality of permanent magnets are arranged circumferentially along the rotating shaft and disposed on an outer peripheral side of the rotating shaft; and A control board is installed on the top of the rotating shaft. A laser emitter is provided on the top of the control board for scanning the surrounding environment.

2. The area coverage scanning laser radar driving device according to claim 1, characterized in that: The coil head end and the tail end of each copper foil layer are provided with a soldering pad, the soldering pad is provided with a via hole, and the via holes of each soldering pad are coaxially aligned in the vertical direction.

3. The area coverage scanning laser radar driving device according to claim 2, characterized in that: A conductive layer is provided on the hole wall of the via hole, and the material of the conductive layer is copper.

4. The area coverage scanning laser radar driving device according to claim 2, characterized in that: The pads on each copper foil layer are distributed axially symmetrically with the rotation axis as the center.

5. The area coverage scanning laser radar driving device according to claim 1, characterized in that: A rotor disk is provided on the rotating shaft and is located on the top of the copper foil layer. The rotor disk is an annular structure. The multiple permanent magnets are embedded on the top of the rotor disk and are arranged at equal intervals along the circumferential direction.

6. The area coverage scanning laser radar driving device according to claim 1, characterized in that: The rotating shaft is provided with a detection device, which is used to detect the change of the magnetic field to obtain the angular position information of the rotating shaft.

7. The area coverage scanning laser radar driving device according to claim 6, characterized in that: The detection device includes at least one position sensor for detecting changes in the magnetic field to obtain position information.

8. The area coverage scanning laser radar driving device according to claim 1, characterized in that: A protective shell is provided on the base, and the protective shell covers the laser emitter.

9. The area coverage scanning laser radar driving device according to claim 8, characterized in that: The base is provided with a mounting structure, which includes a plug-in component. The plug-in component is clamped in the protective shell to limit the protective shell from being separated from the base.

10. The area coverage scanning laser radar driving device according to claim 9, characterized in that: The mounting structure further includes a screw connection piece which penetrates through the side wall of the protective shell and is threadedly connected to the plug-in piece to fix the protective shell.

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