Rotating mirror device and laser radar

Abstract

The invention provides a rotating mirror device and a laser radar. The rotating mirror device comprises a lens support used for bearing a reflector, a driving motor used for driving the lens support to rotate and an anti-shake assembly. The anti-shake assembly comprises a first flange plate and a second flange plate. Wherein the first flange plate is fixed relative to the position of the driving motor, and the second flange plate is fixedly connected with the lens bracket; the second flange plate abuts against the surface of the first flange plate and can slide relative to the surface of the first flange plate. According to the invention, the first flange plate and the second flange plate which abut against each other are added between the driving motor and the lens support, so that friction between the surfaces of the second flange plate and the first flange plate can be carried out when the driving motor drives the lens to rotate; the power output shaft of the driving motor is prevented from shaking by the acting force generated between the power output shaft and the lens support, so that the lens support is prevented from shaking along with the power output shaft, shaking of the reflector can be weakened, and stability of detection and imaging results of the laser radar is improved.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular, to a rotating mirror device and a lidar. Background Art

[0002] A lidar is a device that measures parameters such as the distance and speed of a target object by sending laser light to the surface of the object and then measuring the arrival time of the reflected light beam, etc., and it is widely used in scenarios such as autonomous driving. A common lidar system can be a rotating mirror optical path system; specifically, the rotating mirror optical path system uses a rotating mirror device to drive multiple mirrors to rotate, so as to achieve the divergence of the emitted laser light by reflecting the laser signal. Therefore, there are relatively high requirements for the rotational stability of the rotating mirror device during rotation.

[0003] Currently, in practical applications, the rotating mirror device usually uses an electric motor as the rotation drive source to drive the mirror to rotate. However, since the power output shaft of the electric motor is a rotating shaft with a certain length, it is inevitable that the rotating shaft will shake at high speeds, which will in turn cause the multiple mirrors connected to the rotating shaft to shake, resulting in large errors in the laser signal emitted by the lidar and the received echo signal. Summary of the Invention

[0004] The present invention aims to at least solve the problem that the rotating mirror device of the existing lidar is prone to jitter, and provides a rotating mirror device and a lidar.

[0005] To achieve the object of the present invention, a rotating mirror device is provided, which includes:

[0006] A lens holder for carrying a mirror;

[0007] A driving motor having a power output shaft; the power output shaft is connected to the lens holder to drive the lens holder to rotate;

[0008] An anti-vibration component includes a first flange and a second flange; wherein, the first flange is fixed relative to the driving motor, and the second flange is fixedly connected to the lens holder; the second flange abuts against the surface of the first flange and can slide relative to the surface of the first flange.

[0009] Optionally, at least one of the first flange and the second flange is made of a self-lubricating material.

[0010] Optionally, the self-lubricating material includes Teflon material.

[0011] Optionally, the mirror rotating device further includes: a motor bracket, the motor bracket including a bracket main body; an accommodation space is provided inside the bracket main body, and the driving motor is fixed inside the accommodation space; an installation through hole is provided on the bracket main body; the power output shaft of the driving motor passes through the installation through hole and extends outside the accommodation space.

[0012] Optionally, the motor bracket further includes an installation boss; the installation boss is provided on the surface of the bracket main body facing the lens bracket side; the installation through hole penetrates through the installation boss;

[0013] The first flange is annular; the first flange is arranged around the outer periphery of the installation boss.

[0014] Optionally, the second flange includes a first annular portion and a second annular portion;

[0015] The first annular portion is used for connecting and fixing with the lens bracket;

[0016] The second annular portion is located on the side of the first annular portion away from the lens bracket and is used for abutting against the first flange.

[0017] Optionally, the first annular portion is connected and fixed with the lens bracket by screws.

[0018] Optionally, the motor bracket further includes at least one rotary bearing; the outer ring of the rotary bearing is fixed inside the accommodation space, and the inner ring of the rotary bearing is in fit connection with the outer periphery of the power output shaft.

[0019] Optionally, a ring groove is provided on the surface of the first flange facing the second flange; the ring groove has the same shape as the end of the second annular portion and is used for cooperating with the second annular portion.

[0020] Optionally, the mirror rotating device further includes a shaft locking mechanism; the shaft locking mechanism includes two clamping pieces fixed on the lens bracket; the two clamping pieces are arranged oppositely and are used for clamping on both sides of the power output shaft; the shaft locking mechanism further includes at least one locking screw; the locking screw penetrates through the two clamping pieces and is used for reducing the distance between the two clamping pieces.

[0021] As another technical solution, an embodiment of the present invention further provides a lidar, which includes: a laser signal transceiver module and the mirror rotating device as described above;

[0022] The signal transceiver port of the laser signal transceiver module is arranged facing the circumferential surface of the mirror rotating device, so as to emit a laser signal to a reflecting mirror fixed on the mirror rotating device and receive the laser signal reflected by the reflecting mirror to the signal transceiver port.

[0023] The embodiments of the present invention have the following beneficial effects:

[0024] For the galvanometer device and lidar provided by the embodiments of the present invention, by adding a first flange and a second flange that abut against each other between the driving motor and the lens holder, the second flange can rub against the surface of the first flange during the process of the driving motor driving the lens to rotate, so as to utilize the acting force generated between the two to hinder the shaking of the power output shaft of the driving motor, thereby avoiding the shaking of the lens holder, and further reducing the shaking of the mirror, so as to improve the stability of the detection and imaging results of the lidar. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of a galvanometer device in the related art;

[0026] Figure 2 It is a schematic structural diagram of the galvanometer device provided by the embodiments of the present invention;

[0027] Figure 3 It is a perspective view of the driving motor and the motor holder provided by the embodiments of the present invention;

[0028] Figure 4 It is a perspective view of the galvanometer device provided by the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] Next, the technical solutions in some embodiments of the present disclosure will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present disclosure.

[0030] Unless the context otherwise requires, throughout the specification and claims, the term "comprise" and its other forms, such as the third-person singular form "comprises" and the present participle form "comprising", are to be construed in an open, inclusive sense, i.e., "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example", or "some examples", etc., are intended to indicate that a particular feature, structure, material, or characteristic related to the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials, or characteristics may be included in any one or more embodiments or examples in any suitable manner.

[0031] Hereinafter, 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 quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present disclosure, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0032] "At least one of A, B, and C" has the same meaning as "at least one of A, B, or C", and both include the following combinations of A, B, and C: only A, only B, only C, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B, and C.

[0033] "A and / or B" includes the following three combinations: only A, only B, and the combination of A and B.

[0034] As used herein, "parallel", "perpendicular", and "equal" include the stated cases and cases similar to the stated cases, where the similar cases are within an acceptable deviation range, and the acceptable deviation range is determined by a person of ordinary skill in the art considering the measurements being discussed and the errors associated with the measurements of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, where the acceptable deviation range for approximate parallelism can be, for example, within a deviation of 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, where the acceptable deviation range for approximate perpendicularity can also be, for example, within a deviation of 5°. "Equal" includes absolute equality and approximate equality, where the acceptable deviation range for approximate equality can be, for example, that the difference between the two equal values is less than or equal to 5% of either one of them.

[0035] Exemplary embodiments are described herein with reference to cross-sectional views and / or plan views that are idealized exemplary drawings. In the drawings, the dimensions of some components are adjusted for clarity. Thus, variations in the shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances can be envisioned. Therefore, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but include shape deviations caused by, for example, manufacturing. Thus, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shape of the regions of the device and are not intended to limit the scope of the exemplary embodiments.

[0036] As Figure 1 As shown, in the existing rotating mirror device, the driving motor 01 usually includes two bearings 03 and a power output shaft 02; wherein, the two bearings 03 are sleeved on the outer periphery of the end of the power output shaft 02 to define the rotation axis of the driving motor 01. In order to ensure the normal rotation of the bearings 03, a certain gap needs to be reserved between the balls and the bearing rings in the two bearings 03 to fill the lubricant, that is, the oil gap. However, this gap causes the power output shaft 02 of the driving motor 01 to vibrate slightly during operation, which in turn causes the entire rotating mirror device to vibrate, which will have a great impact on the detection and imaging accuracy of the lidar. Moreover, the conventional oil gap size is usually in the range of 10 - 15um, and if the vibration of the rotating mirror device is to be reduced, the oil gap needs to be controlled within 5um, which will greatly increase the cost of the driving motor, and thus increase the manufacturing cost of the lidar.

[0037] To solve the above technical problems, the present embodiment provides a rotating mirror device that can be applied to a lidar. As Figure 2 shown, the rotating mirror device includes a lens holder 1, a driving motor 2, and an anti-vibration assembly 3.

[0038] Among them, the lens holder 1 is used to carry the reflector 4; specifically, the number of reflectors 4 is multiple, and all are used to reflect the laser emitted by the laser signal transceiver module and reflect the received echo laser to the laser signal transceiver module; further, the reflector 4 is, for example, adhered to the lens holder 1 with an adhesive.

[0039] The drive motor 2 has a power output shaft 21; the power output shaft 21 is connected to the lens holder 1 to drive the lens holder 1 to rotate, so as to drive the multiple reflectors 4 to rotate.

[0040] The anti-vibration component 3 includes a first flange 31 and a second flange 32. Among them, the first flange 31 is fixed relative to the drive motor 2; the second flange 32 is fixedly connected to the lens holder 1, so that the second flange 32 can rotate synchronously with the lens holder 1 during the rotation of the lens holder 1, and thus the second flange 32 can rotate relative to the first flange 31. Moreover, the surface of the second flange 32 abuts against the surface of the first flange 31 and can slide relative to the surface of the first flange 31; in this way, during the process of the drive motor 2 driving the lens holder 1 to rotate, the second flange 32 will rotate relative to the first flange 31, so that continuous friction occurs between the surface of the second flange 32 and the surface of the first flange 31, and the mutual force generated between the two can hinder the shaking movement of the power output shaft 21, thereby preventing the lens holder 1 from shaking accordingly, and further weakening the shaking of the reflector, so as to improve the stability of the detection and imaging results of the lidar.

[0041] It should be noted that, as described above, since one end of the power output shaft 21 is usually installed in the drive motor 2 with a bearing, and the other end extends outside the drive motor 2, the shaking of the power output shaft 21 usually takes the position connected to the bearing as the base point and makes a swinging movement relative to the axis of the initial position of the power output shaft 21, and then it will cause the rotating mirror holder and the second flange 32 connected to the power output shaft 21 to have a swinging tendency. Under this movement tendency, the second flange 32 will exert a force inclined to the surface of the first flange 31 on the first flange 31. Correspondingly, the first flange 31 will exert a reverse frictional force and a supporting force on the second flange 32 to offset the swinging tendency of the second flange 32, thereby preventing the power output shaft 21 from shaking and weakening the shaking of the reflector fixed on the lens holder 1.

[0042] In some embodiments, at least one of the first flange 31 and the second flange 32 is made of a self-lubricating material to reduce the wear of the two during the continuous friction between the first flange 31 and the second flange 32, thereby improving the service life of the anti-vibration component 3.

[0043] Further, in some preferred embodiments, the above self-lubricating material includes Teflon material.

[0044] In some embodiments, the rotating mirror device further includes a motor bracket 5 for mounting the driving motor 2. Specifically, the motor bracket 5 is fixed to the bottom plate of the lidar by screws, for example. As Figure 2 and Figure 3 shown, the motor bracket 5 includes a bracket body which has an accommodation space inside; the driving motor 2 is fixed inside the accommodation space; the bracket body is provided with a mounting through hole; the power output shaft 21 of the driving motor 2 passes through the mounting through hole and extends outside the accommodation space to be connected to the lens bracket 1.

[0045] In some embodiments, the motor bracket can be fixed inside the lidar.

[0046] In some embodiments, as Figure 2 shown, the motor bracket 5 further includes a mounting boss 51. The mounting boss 51 is disposed on the surface of the bracket body facing the lens bracket 1, and the above-mentioned mounting through hole penetrates through the mounting boss 51 for the power output shaft 21 to extend outside the accommodation space. The first flange 31 is annular, and the first flange 31 is disposed around the outer periphery of the mounting boss 51 to radially fix the first flange 31.

[0047] In some specific embodiments, the first flange 31 is fixed to the surface of the motor bracket 5 by screws or adhesives.

[0048] In some embodiments, as Figure 2 shown, the second flange 32 includes a first annular portion 321 and a second annular portion 322. The first annular portion 321 is used for connecting and fixing with the lens bracket 1. The second annular portion 322 is located on the side of the first annular portion 321 away from the lens bracket 1, and the end face of the second annular portion 322 abuts against the first flange 31 to ensure that each position in the circumferential direction can contact the surface of the first flange 31. In this way, no matter which direction the power output shaft 21 sways, the second flange 32 and the first flange 31 can provide reaction forces in the corresponding directions, thereby ensuring to hinder the swaying action of the power output shaft 21.

[0049] In some specific embodiments, the first annular portion 321 is connected and fixed to the lens bracket 1 by screws.

[0050] In some embodiments, the motor bracket 5 further includes at least one rotary bearing 52. The outer ring of the rotary bearing 52 is fixed inside the accommodation space, and the inner ring of the rotary bearing 52 is in fit connection with the outer periphery of the power output shaft 21.

[0051] In some embodiments, a ring groove is formed on the surface of the first flange 31 facing the second flange 32; the ring groove has the same shape as the end of the second ring portion 322 and is used to cooperate with the second ring portion 322 so that the second ring portion 322 can be inserted into the ring groove and can rotate in the ring groove, thereby increasing the friction area between the first flange and the second flange. When the power output shaft 21 shakes, a greater frictional force can be generated between the two to offset the shaking of the power output shaft 21. Moreover, the side wall of the ring groove can also provide a lateral supporting force to the second ring portion 322 to block the lateral shaking of the second ring portion 322 when the power output shaft 21 shakes. However, it should be noted that since the ring groove can provide a large frictional force to the second flange, the driving motor 2 will be subject to a large resistance during the process of driving the lens holder 1 to rotate. It can be seen that the solution of forming a ring groove on the surface of the first flange 31 proposed in this embodiment is applicable to the case where the driving motor 2 has a large torque and may shake significantly.

[0052] In other embodiments, as Figure 3 shown, the surface of the first flange 31 facing the second flange 32 is a flat surface.

[0053] In some embodiments, the rotating mirror device further includes a shaft locking mechanism 6 for connecting the power output shaft 21. The shaft locking mechanism 6 includes two clamping pieces 61 fixed on the lens holder 1; the two clamping pieces 61 are arranged oppositely and are used to clamp both sides of the power output shaft 21; the shaft locking mechanism 6 further includes at least one locking screw 62; the locking screw 62 passes through the two clamping pieces 61 and is used to reduce the distance between the two clamping pieces 61 to clamp the power output shaft 21 and ensure the stable connection between the lens holder 1 and the power output shaft 21.

[0054] In some specific embodiments, as Figure 2 and Figure 4 shown, a mating through hole is formed in the lens holder 1 for the end of the power output shaft 21 to pass through. Moreover, the above-mentioned shaft locking mechanism is arranged on the side of the lens holder 1 away from the driving motor 2, and the two clamping pieces 61 are respectively arranged on both sides of the mating through hole to clamp the end of the power output shaft 21.

[0055] In some specific embodiments, as Figure 3 shown, a flat groove is further formed on one end of the power output shaft 21 that cooperates with the shaft locking mechanism 6 so as to be able to fit with the surface of the clamping piece 61, thereby further ensuring the stable connection between the lens holder 1 and the power output shaft 21.

[0056] As another technical solution, this embodiment further provides a lidar, which includes a laser signal transceiver module and the rotating mirror device described above. The signal transceiver port of the laser signal transceiver module is arranged facing the circumferential surface of the rotating mirror device, for emitting a laser signal to the reflecting mirror 4 fixed on the rotating mirror device and receiving the laser signal reflected by the reflecting mirror 4 towards the signal transceiver port, so as to realize the transceiver of the laser signal, and thus realize the detection and imaging functions through the analysis and calculation of the laser signal.

[0057] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principle of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

1. A rotating mirror device, characterized in that: include: A lens bracket, used for carrying a reflector; A driving motor having a power output shaft; the power output shaft is connected to the lens bracket to drive the lens bracket to rotate; The anti-shake component includes a first flange and a second flange; wherein the first flange is fixed relative to the driving motor, and the second flange is fixedly connected to the lens bracket; the second flange abuts against the surface of the first flange and can slide relative to the surface of the first flange.

2. The rotating mirror device according to claim 1, characterized in that: At least one of the first flange and the second flange is made of a self-lubricating material.

3. The rotating mirror device according to claim 2, characterized in that: The self-lubricating material includes Teflon material.

4. The rotating mirror device according to claim 1, characterized in that: Also includes: A motor bracket, the motor bracket comprising a bracket body; the bracket body has an accommodating space inside, and the driving motor is fixed inside the accommodating space; The bracket body is provided with a mounting through hole; the power output shaft of the driving motor passes through the mounting through hole and extends to the outside of the accommodating space.

5. The rotating mirror device according to claim 4, characterized in that: The motor bracket further comprises a mounting boss; the mounting boss is arranged on a surface of the bracket body on one side facing the lens bracket; the mounting through hole passes through the mounting boss; The first flange is annular; the first flange is arranged around the outer periphery of the mounting boss.

6. The rotating mirror device according to claim 1, characterized in that: The second flange includes a first annular portion and a second annular portion; The first annular portion is used to be connected and fixed to the lens bracket; The second annular portion is located at a side of the first annular portion away from the lens bracket and is used to abut against the first flange.

7. The rotating mirror device according to claim 6, characterized in that: The first annular portion is connected and fixed to the lens bracket by screws.

8. The rotating mirror device according to claim 4, characterized in that: The motor bracket further comprises at least one rotary bearing; the outer ring of the rotary bearing is fixed inside the accommodating space, and the inner ring of the rotary bearing is cooperatively connected with the outer periphery of the power output shaft.

9. The rotating mirror device according to claim 6, characterized in that: An annular groove is formed on the surface of the first flange facing the second flange; the annular groove is consistent in shape with the end of the second annular portion and is used to cooperate with the second annular portion.

10. The rotating mirror device according to claim 1, characterized in that: The rotating mirror device also includes a shaft locking mechanism; the shaft locking mechanism includes two clips fixed on the lens bracket; the two clips are arranged opposite to each other and are used to clamp on both sides of the power output shaft; the shaft locking mechanism also includes at least one locking screw; the locking screw passes through the two clips and is used to reduce the distance between the two clips.

11. A laser radar, characterized in that: include: A laser signal transceiver module and a rotating mirror device as claimed in any one of claims 1 to 10; The signal transceiver port of the laser signal transceiver module is arranged toward the circumference of the rotating mirror device, and is used to transmit laser signals to the reflector fixed on the rotating mirror device, and receive laser signals reflected by the reflector to the signal transceiver port.

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