Prism device and laser radar

Abstract

The embodiment of the utility model provides a prism device and a laser radar, and relates to the technical field of laser radars. The laser radar comprises a prism device, the prism device comprises a prism motor and a plurality of driving parts, the prism motor comprises a rotor and a stator which are connected, the outer side of the rotor is provided with a plurality of reflectors which are arranged at intervals in the circumferential direction, the sides, away from the rotor, of the reflectors are reflecting surfaces, and the rotor can drive the reflectors to rotate around a first axis. The plurality of driving parts and the plurality of reflectors are arranged in a one-to-one correspondence mode, the reflectors can rotate around a second axis through the driving parts, and an included angle is formed between the second axis and the first axis. Under the action of the driving piece and the mover, the reflecting mirror on the outer side of the mover can rotate in multiple directions, so that three-dimensional scanning is realized, the use of two motors for respectively driving a prism and a galvanometer is avoided, and the size of the whole structure can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of laser radar, and in particular to a prism device and a laser radar. Background Art

[0002] With the rise of intelligent driving, scanning radar has also been widely used. The current scanning methods of radar include single-point or linear array radar plus mechanical scanning of motors.

[0003] The inventors have found that when the prism and the galvanometer in some existing three-dimensional scanning mechanisms are moving, two motors are needed to drive the laser radar and the galvanometer to rotate respectively, and the overall volume is relatively large. Utility Model Content

[0004] The utility model aims to provide a prism device which can reduce the overall volume.

[0005] The embodiment of the utility model is achieved as follows:

[0006] In a first aspect, the utility model provides a prism device, comprising:

[0007] The prism motor includes a mover and a stator connected to each other. A plurality of reflectors arranged at intervals along the circumferential direction are arranged on the outer side of the mover. The side of the reflector away from the mover is a reflective surface. The mover can drive the reflector to rotate around a first axis.

[0008] Multiple driving members are arranged one by one with multiple reflectors. The reflectors can be rotated around a second axis through the driving members. The second axis forms an angle with the first axis. For each reflector, the reflector has a first end and a second end relative to each other in its own length direction. When the reflector rotates around the second axis, one of the first end and the second end is relatively close to the mover, and the other of the first end and the second end is relatively far away from the mover.

[0009] Through the above arrangement, under the action of the driving member and the mover, the reflector on the outside of the mover can rotate in multiple directions, thereby realizing three-dimensional scanning, avoiding the use of two motors that drive the prism and the galvanometer respectively, thereby reducing the volume of the overall structure.

[0010] In an optional embodiment, there is a driving member between each reflector and the outer peripheral wall of the mover, the driving member includes an electromagnetic ring, and a magnetic member is provided on the side of the reflector close to the mover. The electromagnetic ring can cooperate with the magnetic member to drive the reflector to rotate around the second axis.

[0011] Through the above arrangement, the reflection mirror can be rotated around the second axis through the cooperation between the magnetic member and the electromagnetic ring.

[0012] In an optional embodiment, each driving member includes two electromagnetic coils, and the two electromagnetic coils in the driving member are respectively located at the first end and the second end of the reflector.

[0013] Through the above arrangement, the lower sides of both ends of the reflector can be driven by the two electromagnetic coils respectively, so as to realize the rotation of the reflector around the second axis.

[0014] In an optional embodiment, the prism device also includes a disc slip ring, which is connected to the stator and is located at one end of the mover, and a plurality of electrical connection parts arranged along the intervals are provided at one end of the mover close to the disc slip ring, and the electrical connection parts are electrically connected to the electromagnetic coil, and the electrical connection parts are used to be electrically connected to the disc slip ring, and a plurality of connecting cables are provided at one end of the disc slip ring away from the mover, and the electromagnetic coil is electrically connected to the electrical connection parts.

[0015] Through the above arrangement, electrical connection between the rotating mover and the fixed disc slip ring is achieved.

[0016] In an optional embodiment, a plurality of circumferentially spaced mounting grooves are provided on the outer side of the mover, and each reflector has a first side and a second side relative to each other in its width direction. A connecting shaft is provided on the first side and the second side, and the connecting shaft is rotatably connected to the inner side wall of the mounting groove, and the axis of the connecting shaft is the second axis.

[0017] Through the above arrangement, the area of ​​the reflector exposed to the outside is reduced by the mounting groove, thereby reducing the influence of external impurities on the reflector.

[0018] In an optional embodiment, the number of the reflectors and the number of the driving members are both four, and the four reflectors are evenly spaced and arranged along the circumference of the mover.

[0019] Through the above configuration, the four reflectors are evenly arranged, which can ensure that the optical signal can be reflected relatively evenly on the periphery of the mover.

[0020] In an optional embodiment, the prism device further includes a code disk, which is coaxially arranged with the mover and the mover is sleeved on the code disk, and the code disk is fixedly connected to the mover.

[0021] The above arrangement can facilitate the external control module to control the rotation of the mover.

[0022] In an optional embodiment, the code disc and the mover are an integral structure, or the mover and the code disc are bonded, or the mover and the code disc are interference fit.

[0023] Through the above settings, the connection strength between the code disc and the mover is guaranteed.

[0024] In an optional embodiment, the prism device further includes a bearing, the bearing is sleeved on the stator, and the code disc is sleeved on the bearing.

[0025] Through the above arrangement, the rotation efficiency of the mover can be better improved.

[0026] In an optional embodiment, the stator has a first end and a second end opposite to each other along its own axis direction;

[0027] The first end extends out of the mover for fixed connection with an external device, and / or the second end extends out of the mover for fixed connection with an external device.

[0028] Through the above-mentioned arrangement, it is possible to facilitate fixing the laser radar on an external device, thereby achieving fixation of the laser radar.

[0029] In an optional embodiment, the second axes of the plurality of reflectors are coplanar, the first axis is perpendicular to the preset plane, and the second axis is parallel to the preset plane.

[0030] In a second aspect, the utility model provides a laser radar, comprising a prism device according to any one of the aforementioned embodiments.

[0031] The beneficial effects of the embodiment of the utility model are as follows: the embodiment of the utility model provides a prism device and a laser radar, the laser radar includes a prism device, the prism device includes a prism motor and a plurality of driving members, the prism motor includes a connected mover and a stator, a plurality of reflectors arranged at intervals along the circumferential direction are arranged on the outer side of the mover, the side of the reflector away from the mover is a reflection surface, the mover can drive the reflector to rotate around a first axis, a plurality of driving members and a plurality of reflectors are arranged one by one, a driving member is provided between each reflector and the outer peripheral wall of the mover, the reflector can rotate around a second axis through the driving member, the second axis is at an angle to the first axis, the reflector has a first end and a second end relative to each other in its length direction, when the reflector rotates around the second axis, one of the first end and the second end is relatively close to the mover, and the other of the first end and the second end is relatively far away from the mover. Under the action of the driving member and the mover, the reflector outside the mover can rotate in multiple directions, thereby realizing three-dimensional scanning, avoiding the use of two motors that drive the prism and the galvanometer respectively, thereby reducing the volume of the overall structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic structural diagram of a prism device provided in an embodiment of the utility model.

[0034] Icons: 1-prism device; 100-prism motor; 110-stator; 111-first shaft end; 112-second shaft end; 120-bearing; 130-code disk; 140-mover; 141-mounting groove; 150-disc slip ring; 151-connecting cable; 160-electrical connection part; 200-reflector; 210-reflecting surface; 220-connecting shaft; 300-driving member; 310-electromagnetic coil. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0039] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0040] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] The specific structure of a prism device provided by an embodiment of the utility model and the corresponding technical effects it brings are described in detail below in conjunction with the patent drawings.

[0042] Please refer to Figure 1 A prism device 1 provided in an embodiment of the utility model includes a prism motor 100 and a plurality of driving components 300 .

[0043] The prism motor 100 includes a connected mover 140 and a stator 110. A plurality of reflectors 200 arranged at intervals along the circumferential direction are arranged on the outer side of the mover 140. The side of the reflector 200 away from the mover 140 is a reflecting surface 210. The mover 140 can drive the reflector 200 to rotate around a first axis. A plurality of driving members 300 are arranged one-to-one with the plurality of reflectors 200. A driving member 300 is provided between each reflector 200 and the outer peripheral wall of the mover 140. The reflector 200 can rotate around a second axis through the driving member 300. The second axis is at an angle to the first axis. The first axis is perpendicular to a preset plane. The second axis is at an obtuse angle or an acute angle to the preset plane, or the second axis is parallel to the preset plane.

[0044] In this embodiment, the second axis is not perpendicular to the preset plane.

[0045] That is to say, driven by the mover 140 and the driving member 300, each reflector 200 can rotate around the first axis and the second axis, and the first axis is coaxial with the rotation axis of the mover 140. Figure 1 For reference, the reflector 200 can rotate in the horizontal direction driven by the mover 140, and the reflector 200 performs a pitch motion outside the mover 140 under the action of the driving member 300. The reflector 200 has a relative first end and a second end in its own length direction. When the reflector 200 rotates around the second axis, one of the first end and the second end is relatively close to the mover 140, and the other of the first end and the second end is relatively far away from the mover 140.

[0046] In some existing laser radars, a prism is connected to a motor, and a galvanometer is connected to a motor, wherein the prism rotates around an axis driven by the motor, and when the prism is placed vertically, the rotation axis of the prism is perpendicular to the horizontal plane, and the galvanometer performs pitch motion around an axis driven by the motor, and the rotation axis of the galvanometer is parallel to the horizontal plane, and three-dimensional scanning is achieved under the action of the galvanometer and the prism, but it requires two electrodes, which is relatively large.

[0047] Under the action of the driving member 300 and the mover 140, the reflector 200 outside the mover 140 can rotate in multiple directions to achieve three-dimensional scanning, avoiding the use of two motors that drive the prism and the galvanometer respectively, thereby reducing the volume of the overall structure.

[0048] It should be noted that, in this embodiment, the outer side of the mover 140 should be understood as the outer peripheral wall of the mover 140 .

[0049] It should be noted that, in this embodiment, the second axis of rotation of each reflector 200 relative to the stator 110 is perpendicular to the first axis. Of course, the verticality in this embodiment should not be understood as verticality in a strict sense, as long as it is approximately vertical.

[0050] It can be understood that the directions of the second axis of rotation of each reflector 200 relative to the stator 110 are different, but the second axis of rotation of each reflector 200 relative to the stator 110 is parallel to the preset plane.

[0051] Of course, in some other embodiments, the second axis may also form an angle with the first axis.

[0052] Optionally, in some embodiments, the second axes of the plurality of reflectors 200 are all in a preset plane, and the preset plane is perpendicular to the first axis.

[0053] In this embodiment, the driving member 300 includes an electromagnetic coil 310. A magnetic member is provided on one side of the reflector 200 close to the mover 140. The electromagnetic coil 310 can cooperate with the magnetic member to drive the reflector 200 to rotate around the second axis. It can be understood that the electromagnetic coil 310 is relatively close to the first end or the second end of the reflector 200. When the electromagnetic coil 310 is energized, it can give the magnetic member an attractive or repulsive force to rotate the electromagnetic coil 310 around the second axis.

[0054] It should be noted that the electromagnetic coil 310 is fixedly disposed on the outer wall of the mover 140 .

[0055] Optionally, in this embodiment, each driving member 300 includes two electromagnetic coils 310, and the two electromagnetic coils 310 in the driving member 300 are respectively located at the first end and the second end of the reflector 200. It can be understood that the two electromagnetic coils 310 are respectively connected to the power supply control, and by arranging the electromagnetic coils 310 at the lower sides of the first end and the second end of the reflector 200, it is convenient for the user to individually control the two electromagnetic coils 310 of each driving member 300, so that the reflector 200 can pitch around the second axis.

[0056] The prism device 1 also includes a disc slip ring 150, which is connected to the stator 110 and is located at one end of the mover 140. A plurality of electrical connection parts 160 arranged at intervals are provided at one end of the mover 140 close to the disc slip ring 150. The electrical connection part 160 is electrically connected to the electromagnetic coil 310. The electromagnetic coil 310 is electrically connected to the electrical connection part 160. The electrical connection part 160 is used to be electrically connected to the disc slip ring 150. The electrical connection part 160 can also be electrically connected to other parts of the prism device 1. A plurality of connecting cables 151 are provided at one end of the disc slip ring 150 away from the mover 140. It can be understood that the connecting cables 151 are used for external power supply.

[0057] That is, the electromagnetic coil 310 is electrically connected to the disk slip ring 150 through the electrical connection portion 160 , and other components of the prism device are also electrically connected to the disk slip ring 150 through the electrical connection portion 160 .

[0058] It should be noted that the number of connecting cables 151 is the same as the number of electrical connecting parts 160 and they are electrically connected one-to-one, that is, the user can control the connection between the external power supply and the connecting cables 151 to control the power supply of the components electrically connected to the electrical connecting parts 160.

[0059] Optionally, in some embodiments, each electromagnetic coil 310 is electrically connected to an electrical connection portion 160 , that is, a user can control the connection between an external power source and the connecting cable 151 to control the power supply status of each electromagnetic coil 310 .

[0060] Optionally, in some other embodiments, the electromagnetic coils 310 in the multiple driving members 300 are divided into multiple groups. When the number of the electromagnetic coils 310 in each driving member 300 is two, the multiple electromagnetic coils 310 are divided into two groups. The two groups are arranged at intervals along the axial direction of the mover 140, and the electromagnetic coils 310 in each group are arranged at intervals along the circumferential direction of the mover 140. The electromagnetic coils 310 in each group are electrically connected to an electrical connection part 160 at the same time.

[0061] Optionally, a plurality of circumferentially spaced mounting grooves 141 are provided on the outer side of the mover 140, and each reflector 200 has a first side and a second side opposite to each other in its width direction, and a connecting shaft 220 is provided on both the first side and the second side, and the connecting shaft 220 is rotatably connected to the inner side wall of the mounting groove 141, and the axis of the connecting shaft 220 is the second axis. It can be understood that by providing the mounting groove 141, the area of ​​the reflector 200 exposed to the external space can be reduced, thereby reducing the impact of external debris on the reflector 200.

[0062] It should be noted that the width direction of the reflector 200 forms an angle with the length direction of the reflector 200 .

[0063] In detail, in this embodiment, the number of the reflectors 200 and the number of the driving members 300 are both four. Similarly, the number of the mounting grooves 141 is also four. The four reflectors 200 are evenly spaced along the circumference of the mover 140 so that the reflection effect of each part is relatively uniform when the mover 140 rotates.

[0064] Of course, in some optional embodiments, the number of the reflector 200, the driving member 300 and the mounting slot 141 is not limited to four, as long as there are more than one, and the more in this embodiment should be understood as two or more than two.

[0065] Optionally, the second axes of the plurality of reflectors 200 are coplanar, the first axes are perpendicular to the preset plane, and the second axes are parallel to the preset plane.

[0066] It should be noted that the uniformity in this embodiment is not limited to uniformity in a strict sense, as long as it is roughly uniform.

[0067] In order to facilitate the control of the external control module, in this embodiment, the prism device 1 further includes a code disk 130 , which is coaxially arranged with the mover 140 and the mover 140 is sleeved on the code disk 130 , and the code disk 130 and the mover 140 are fixedly connected.

[0068] The encoder rotates coaxially with the motor shaft to ensure that it can accurately measure every tiny rotation. This data is fed back to the control system so that the system can adjust the operation of the motor more accurately and achieve the desired speed control, position control or torque control.

[0069] Optionally, in some embodiments, the code disc 130 and the mover 140 are an integral structure, the mover 140 and the code disc 130 are bonded to each other, or the mover 140 and the code disc 130 are interference fit.

[0070] Of course, in some other embodiments, the code disc 130 and the mover 140 may also be detachably connected, for example, by snapping or by threaded fasteners or by latches.

[0071] Optionally, the prism device 1 further includes a bearing 120 , the bearing 120 is sleeved on the stator 110 , the code disc 130 is sleeved on the bearing 120 , and the mover 140 is sleeved on the code disc 130 . The bearing 120 can better improve the rotation efficiency of the mover 140 .

[0072] In this embodiment, the stator 110 has a first shaft end 111 and a second shaft end 112 relative to each other along its own axial direction. The first shaft end 111 extends out of the mover 140 for fixed connection with an external device, and the second shaft end 112 extends out of the mover 140 for fixed connection with an external device. Both the first shaft end 111 and the second shaft end 112 can be fixedly connected to an external device, thereby improving the stability of the fixation of the prism motor 100.

[0073] The embodiment of the utility model further provides a laser radar (not shown in the figure), including the above-mentioned prism device 1. It can be understood that since the laser radar includes the prism device 1, the laser radar also has the beneficial effects of the prism device 1, so the beneficial effects of the laser radar are not described in detail here.

[0074] In summary, the embodiment of the utility model provides a prism device 1 and a laser radar, the laser radar includes a prism device 1, the prism device 1 includes a prism motor 100 and a plurality of driving members 300, the prism motor 100 includes a mover 140 and a stator 110 connected to each other, a plurality of reflectors 200 arranged at intervals along the circumferential direction are arranged on the outer side of the mover 140, a side of the reflector 200 away from the mover 140 is a reflecting surface 210, the mover 140 can drive the reflector 200 to rotate around a first axis, and the plurality of driving members 300 are arranged on the outer side of the mover 140. 0 is arranged one by one with a plurality of reflectors 200, and a driving member 300 is provided between each reflector 200 and the outer peripheral wall of the mover 140. The reflector 200 can be rotated around a second axis through the driving member 300, and the second axis is at an angle to the first axis. The reflector 200 has a first end and a second end opposite to each other in its length direction. When the reflector 200 rotates around the second axis, one of the first end and the second end is relatively close to the mover 140, and the other of the first end and the second end is relatively far away from the mover 140. Under the action of the driving member 300 and the mover 140, the reflector 200 outside the mover 140 can rotate in multiple directions, thereby realizing three-dimensional scanning, avoiding the use of two motors that drive the prism and the galvanometer respectively, and thus reducing the volume of the overall structure.

[0075] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A prism device, characterized in that: include: A prism motor (100), the prism motor (100) comprising a mover (140) and a stator (110) connected to each other, a plurality of reflectors (200) arranged at intervals in the circumferential direction are arranged outside the mover (140), a side of the reflector (200) away from the mover (140) being a reflective surface (210), and the mover (140) can drive the reflector (200) to rotate around a first axis; A plurality of driving members (300) are provided, wherein the plurality of driving members (300) and the plurality of reflecting mirrors (200) are arranged in a one-to-one correspondence, wherein the reflecting mirrors (200) can be rotated around a second axis through the driving members (300), wherein the second axis forms an angle with the first axis, and for each of the reflecting mirrors (200), the reflecting mirror (200) has a first end and a second end that are opposite to each other in its length direction, and when the reflecting mirror (200) rotates around the second axis, one of the first end and the second end is relatively close to the mover (140), and the other of the first end and the second end is relatively far away from the mover (140).

2. The prism device according to claim 1, characterized in that: A driving member (300) is provided between each of the reflectors (200) and the outer peripheral wall of the mover (140), and the driving member (300) comprises an electromagnetic ring (310). A magnetic member is provided on a side of the reflector (200) close to the mover (140), and the electromagnetic ring (310) can cooperate with the magnetic member to drive the reflector (200) to rotate around the second axis.

3. The prism device according to claim 2, characterized in that: Each of the driving components (300) comprises two electromagnetic coils (310), and the two electromagnetic coils (310) in the driving component (300) are respectively located at the first end and the second end of the reflector (200).

4. The prism device according to claim 3, characterized in that: The prism device further comprises a disc slip ring (150), wherein the disc slip ring (150) is connected to the stator (110) and is located at one end of the mover (140); a plurality of electrical connection parts (160) arranged along intervals are arranged at one end of the mover (140) close to the disc slip ring (150); the electrical connection parts (160) are electrically connected to the electromagnetic coil (310); the electrical connection parts (160) are used to be electrically connected to the disc slip ring (150); a plurality of connection cables (151) are arranged at one end of the disc slip ring (150) away from the mover (140); and the electromagnetic coil (310) is electrically connected to the electrical connection parts (160).

5. The prism device according to claim 2, characterized in that: The outer side of the mover (140) is provided with a plurality of circumferentially spaced mounting grooves (141), each of the reflectors (200) has a first side and a second side opposite to each other in its width direction, the first side and the second side are both provided with a connecting shaft (220), the connecting shaft (220) is rotatably connected to the inner side wall of the mounting groove (141), and the axis of the connecting shaft (220) is the second axis.

6. The prism device according to claim 1, characterized in that: The number of the reflectors (200) and the number of the driving members (300) are both four, and the four reflectors (200) are evenly spaced and arranged along the circumference of the mover (140).

7. The prism device according to claim 1, characterized in that: The prism device further comprises a code disc (130), the code disc (130) and the mover (140) are coaxially arranged and the mover (140) is sleeved on the code disc (130), and the code disc (130) and the mover (140) are fixedly connected.

8. The prism device according to claim 7, characterized in that: The code disc (130) and the mover (140) are an integral structure, or the mover (140) and the code disc (130) are bonded, or the mover (140) and the code disc (130) are interference fit.

9. The prism device according to claim 7, characterized in that: The prism device further comprises a bearing (120), wherein the bearing (120) is sleeved on the stator (110), and the code disc (130) is sleeved on the bearing (120).

10. The prism device according to claim 1, characterized in that: The stator (110) has a first axial end (111) and a second axial end (112) which are opposite to each other along its own axial direction; The first shaft end (111) extends out of the mover (140) for fixed connection with an external device, and / or the second shaft end (112) extends out of the mover (140) for fixed connection with an external device.

11. The prism device according to claim 1, characterized in that: The second axes of the plurality of reflectors (200) are coplanar, the first axis is perpendicular to a preset plane, and the second axis is parallel to the preset plane.

12. A laser radar, characterized in that: A prism device comprising any one of claims 1-11.

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