Automatic focusing device and projection optical machine

Abstract

The application discloses an automatic focusing device and a projection light machine, and relates to the technical field of micro laser projection, wherein the automatic focusing device comprises a support, a focusing mechanism, a positioning mechanism and a shielding mechanism; the focusing mechanism comprises a driving assembly, a transmission assembly and a lens assembly; the driving assembly is in transmission connection with the lens assembly through the transmission assembly; the positioning mechanism comprises a magnetic positioning piece and a positioning detection piece; the shielding mechanism comprises a fixed shielding shell and a sliding shielding shell; one of the magnetic positioning piece and the positioning detection piece is arranged in the fixed shielding shell, and the other is arranged in the sliding shielding shell. The magnetic signal of the magnetic positioning piece is detected by the positioning detection piece, so that the position of the lens assembly can be acquired in real time, the position of the lens assembly can be adjusted directly through the driving assembly, the process of driving the lens assembly to reset is saved, the focusing time is reduced, and the focusing accuracy is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of micro laser projection, in particular to an automatic focusing device and a projection light machine. BACKGROUND

[0002] The current light machine lens adopts the inductive technology of photo-coupler to determine the rotation angle of the gear, and then determines the current position of the light machine shell lens. However, only the positions of the two photo-coupler points can have position data reading, and the position information of the transmission of the focusing part and the rotation of the gear has no visibility in the rotation process. In addition, due to the gear transmission design of the reduction box and the motor itself, the stepping motor will generally produce an empty return phenomenon in the rotation process. Once the motor rotates empty or the gear transmission cooperates with the sliding tooth deviation, the motor drive signal issued by the micro control unit controlling the motor cannot accurately control the focusing position of the motor rotation direction. Therefore, in order to avoid the deviation of the focusing position caused by the motor rotation empty or the gear transmission cooperating with the sliding tooth, the existing automatic focusing technology is to completely retreat the gear to the starting point photo-coupler position, and then positively push the motor and the gear to rotate to the focusing clear position of the focusing part, which will cause the automatic focusing time to be too long. SUMMARY

[0003] The main purpose of the present application is to provide an automatic focusing device and a projection light machine, which aims to improve the automatic focusing accuracy and reduce the automatic focusing time.

[0004] To achieve the above purpose, the automatic focusing device provided by the present application comprises:

[0005] A support;

[0006] A focusing mechanism, the focusing mechanism comprising a driving assembly, a transmission assembly and a lens assembly, the driving assembly being connected with the support, the driving assembly being drivingly connected with the lens assembly through the transmission assembly, so that the driving assembly can drive the lens assembly to move along the axial direction of the lens assembly through the transmission assembly;

[0007] A positioning mechanism, the positioning mechanism comprising a magnetic positioning part and a positioning detection part, the positioning detection part being used to acquire the position of the magnetic positioning part in real time by detecting the magnetic field strength change of the magnetic positioning part; the positioning detection part being electrically connected with the driving assembly, so that the driving assembly can drive the lens assembly to move or be stationary according to the position of the magnetic positioning part;

[0008] The shielding mechanism comprises a fixed shielding shell and a sliding shielding shell, the fixed shielding shell and the sliding shielding shell enclose a closed space, the sliding shielding shell is movably installed on the fixed shielding shell for adjusting the size of the closed space, the fixed shielding shell is connected with the support, the sliding shielding shell is connected with the lens assembly, one of the magnetic positioning member and the positioning detection member is arranged in the fixed shielding shell, and the other is arranged in the sliding shielding shell.

[0009] In an embodiment, the transmission assembly comprises a focusing lens barrel and a focusing member, the focusing lens barrel is connected with the support, the focusing member is sleeved on the periphery of the focusing lens barrel and can rotate relative to the focusing lens barrel, the focusing lens barrel is provided with a guide hole extending along the axial direction of the lens assembly, the focusing member is provided with a screw adjusting hole, the lens assembly comprises a lens body and a guide pin connected with each other, the sliding shielding shell is connected with the lens body, the guide pin passes through the guide hole and the screw adjusting hole, and the driving assembly is in transmission connection with the focusing member, so that the driving assembly can drive the focusing member to rotate relative to the focusing lens barrel, and the focusing member can also drive the lens body to move through the guide pin.

[0010] In an embodiment, the transmission assembly further comprises a gear and an arc-shaped rack, the driving assembly comprises a driving motor, the driving motor is connected with the support, the positioning detection member is in electrical connection with the driving motor, the gear is arranged on the rotating shaft of the driving motor, the arc-shaped rack is arranged on the outer wall of the focusing member, the gear is in meshing connection with the arc-shaped rack, and the driving motor can drive the focusing member to rotate relative to the focusing lens barrel and drive the lens body to move through the gear and the arc-shaped rack.

[0011] And / or, the inner wall of the focusing lens barrel is in abutment with the outer wall of the lens body, for limiting the movement of the lens body relative to the focusing lens barrel along the radial direction of the lens body;

[0012] And / or, the inner wall of the focusing member is in abutment with the outer wall of the focusing lens barrel, for limiting the movement of the focusing member relative to the focusing lens barrel along the radial direction of the lens body;

[0013] And / or, the two hole walls of the guide hole are in abutment with the guide pin, for limiting the movement of the lens body relative to the focusing lens barrel along the circumferential direction of the lens body;

[0014] And / or, the number of the guide holes is at least two, the at least two guide holes are arranged at intervals along the circumferential direction of the focusing lens barrel, the number of the screw adjusting holes is consistent with and one-to-one corresponds to the number of the guide holes, and the number of the guide pins is consistent with and one-to-one corresponds to the number of the guide holes.

[0015] In an embodiment, the transmission assembly comprises a focusing lens barrel connected with the bracket, the focusing lens barrel is provided with a guide hole extending along the axial direction of the lens assembly, the lens assembly comprises a lens body and a guide pin connected with each other, the sliding shield shell is connected with the lens body, the focusing lens barrel is sleeved on the lens body, the guide pin passes through the guide hole, the two oppositely arranged hole walls of the guide hole are in abutment with the guide pin, for limiting the movement of the lens body along the circumferential direction of the lens body relative to the focusing lens barrel, and the driving assembly is in transmission connection with the guide pin, so that the driving assembly can drive the lens body to move along the axial direction of the lens body through the guide pin.

[0016] In an embodiment, the inner wall of the focusing lens barrel is in abutment with the outer wall of the lens body, for limiting the movement of the lens body along the radial direction of the lens body relative to the focusing lens barrel.

[0017] And / or, the number of the guide holes is at least two, the at least two guide holes are arranged at intervals along the circumferential direction of the focusing lens barrel, and the guide pin is arranged in one-to-one correspondence with the number of the guide holes.

[0018] In an embodiment, the automatic focusing device further comprises a calibration mechanism, the calibration mechanism comprises an adjusting member and an elastic member; the magnetic positioning member is located in the sliding shield shell and is in movable connection with the sliding shield shell, the positioning detection member is located in the fixed shield shell and is in fixed connection with the fixed shield shell, one end of the adjusting member is located outside the sliding shield shell, the other end of the adjusting member is located in the sliding shield shell and is in abutment with the magnetic positioning member, the elastic member is located in the sliding shield shell, one end of the elastic member is connected with the magnetic positioning member, and the other end of the elastic member is connected with the sliding shield shell, the adjusting member is movably installed on the sliding shield shell, so that the adjusting member and the elastic member can drive the magnetic positioning member to reciprocate along the axial direction of the lens assembly.

[0019] In an embodiment, the calibration mechanism further comprises two guide plates arranged at intervals, a guide channel extending along the axial direction of the lens assembly is formed between the two guide plates, the magnetic positioning member is located in the guide channel, one end of the elastic member towards the adjusting member is in abutment with the magnetic positioning member, and the adjusting member and the elastic member can drive the magnetic positioning member to reciprocate along the axial direction of the lens assembly in the guide channel.

[0020] In an embodiment, the adjusting member is an adjusting screw, the elastic member is a spring, the sliding shielding shell is provided with a threaded hole, the adjusting screw is threadedly connected with the threaded hole, one end of the spring is in abutment with the magnetic positioning member, and the other end of the spring is connected with the sliding shielding shell.

[0021] In an embodiment, the fixed shielding shell is provided with a first opening in communication with an internal cavity of the fixed shielding shell, the sliding shielding shell is provided with a second opening in communication with an internal cavity of the sliding shielding shell, one end of the sliding shielding shell provided with the second opening is inserted into the fixed shielding shell through the first opening, so that the internal cavities of the fixed shielding shell and the sliding shielding shell are in communication with each other to form the sealed space, and the outer wall of the sliding shielding shell is in sliding fit with the inner wall of the fixed shielding shell.

[0022] In an embodiment, the inner wall of the fixed shielding shell is inwardly protruded to form a guide rail extending along the axial direction of the lens assembly, and the outer wall of the sliding shielding shell is formed with a guide sliding groove in sliding fit with the guide rail.

[0023] The application further provides a projection light machine comprising a housing and the automatic focusing device.

[0024] The technical scheme of the application acquires the position of the magnetic positioning member by detecting the magnetic signal of the magnetic positioning member through the positioning detection member, and acquires the position of the lens assembly in real time through the positioning detection member when the magnetic positioning member is located in the sliding shielding shell, so that the lens assembly is driven to adjust the position by the driving assembly and the transmission assembly according to the position of the lens assembly, the process of adjusting the position after the lens assembly is driven to reset is saved, and the focusing time is reduced. The positioning detection member controls the driving assembly to stop running when the lens assembly moves to the specified position, so that the lens assembly stays at the position, and the focusing accuracy is improved. The magnetic positioning member and the positioning detection member are arranged in the sealed space, so that the interference of the external magnetic field on the positioning detection member is reduced, the accuracy of the positioning detection member is improved, the position of the lens assembly is more accurately acquired by the positioning detection member, the position of the lens assembly is more accurately adjusted, and the focusing accuracy is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to make the technical solutions in the embodiments of the present application or the prior art clearer, the accompanying drawings needed in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description only show some embodiments of the present application, and for those skilled in the art, other drawings can be obtained from the structures shown in the drawings without any creative effort.

[0026] Figure 1 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0027] Figure 2 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application; Figure 1 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0028] Figure 3 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application; Figure 1 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0029] Figure 4 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0030] Figure 5 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application; Figure 4 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0031] Figure 6 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application; Figure 4 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0032] Figure 7 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application; Figure 4 Partial structural schematic diagram of an embodiment of the automatic focusing device provided by the present application;

[0033] Figure 8 Structural schematic diagram of an embodiment of the shielding mechanism provided by the present application;

[0034] Figure 9 Structural schematic diagram of an embodiment of the shielding mechanism provided by the present application and the lens body and the support;

[0035] Figure 10 Structural schematic diagram of an embodiment of the shielding mechanism provided by the present application.

[0036] Explanation of the reference signs:

[0037] 100, automatic focusing device; 1, support; 2, focusing mechanism; 21, driving assembly; 22, transmission assembly; 221, focusing lens barrel; 2211, guide hole; 222, focusing piece; 2221, screw adjusting hole; 223, gear; 224, arc-shaped rack; 23, lens assembly; 231, lens body; 232, guide pin; 3, positioning mechanism; 31, magnetic positioning piece; 32, positioning detection piece; 4, shielding mechanism; 41, fixed shielding shell; 411, first opening; 42, sliding shielding shell; 421, second opening; 43, closed space; 5, calibration mechanism; 51, adjusting piece; 52, elastic piece; 53, guide plate.

[0038] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments in combination with the accompanying drawings. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0040] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.

[0041] In addition, if the embodiments of the present application involve descriptions of "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In addition, "and / or" or "and / or" appearing throughout the text means that the three parallel schemes are included, for example, "A and / or B" includes A scheme, or B scheme, or A and B are satisfied at the same time. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of protection claimed by the present application.

[0042] The current optical machine lens adopts the inductive technology of optical coupling to determine the rotation angle of the gear, and then determine the current position of the optical machine shell lens. However, only the position of the two optical coupling points can have position data reading. In the process of rotation, the position information of the transmission of the focusing part and the rotation of the gear cannot be seen. In addition, due to the gear transmission design of the reduction box and the motor itself, the stepping motor will generally produce an empty return phenomenon in the rotation process. Once the motor rotates empty or the gear transmission cooperates with the sliding tooth deviation, the motor driving signal sent by the micro control unit controlling the motor cannot accurately control the focusing position of the motor rotation direction. Therefore, in order to avoid the deviation of the focusing position caused by the motor rotating empty or the gear transmission cooperating with the sliding tooth, the existing automatic focusing technology is to completely retreat the gear to the starting point of the optical coupling position, and then positively push the motor and the gear to rotate to the focusing clear position of the focusing part. This will result in a long time for automatic focusing.

[0043] The inventor found that the existing method of using two optical couplings to obtain the position of the lens cannot obtain the position of the lens in real time. The distance between the two can only be obtained after the light emitted by one optical coupling is received by the other. Therefore, the optical coupling cannot know the position of the lens after focusing each time, so it cannot further adjust the position of the lens according to the current position of the lens. Therefore, the lens needs to be reset first because the starting position is determined, and then the position of the lens is adjusted. Therefore, the existing adjustment method basically experiences a reset each time the lens focuses, which results in a long time for focusing. Since the optical coupling detection cannot obtain the real-time position of the lens in real time, the existing adjustment method basically controls the position of the lens through the driving signal of the control unit. In simple terms, if the position to be reached by the lens requires the rotation shaft of the driving motor to rotate two circles, the control unit will send a control signal to the driving motor to rotate two circles. However, the existing stepping motor generally has an empty return phenomenon (the empty return phenomenon of the stepping motor refers to the phenomenon that the motor shaft rotates slightly in the opposite direction or deviates from the position without a driving signal after the motor stops driving due to the gap in the mechanical structure or the electromagnetic characteristics). This results in that although the motor receives a signal to rotate two circles, it also completes the task of rotating two circles. However, due to the empty return phenomenon, the lens may not accurately stop at the position where the motor rotates two circles. Since the optical coupling cannot detect the position of the lens in real time, the lens may not only move to the specified position after the motor rotates, but also cannot detect whether it moves to the specified position, which results in low focusing accuracy. In order to avoid the influence of the superposition of several rotations after multiple rotations, the existing technology resets the lens before adjusting, so that the rotation phenomenon caused by each adjustment occurs at most once, to ensure the focusing accuracy.

[0044] The application provides an automatic focusing device and a projection light machine, aiming at improving the automatic focusing precision and reducing the automatic focusing time.

[0045] Please refer to Figure 1 、 Figure 4 and Figure 9 In an embodiment of the application, the automatic focusing device 100 comprises a support 1, a focusing mechanism 2, a positioning mechanism 3 and a shielding mechanism 4. The focusing mechanism 2 comprises a driving assembly 21, a transmission assembly 22 and a lens assembly 23. The driving assembly 21 is connected with the support 1. The driving assembly 21 is in transmission connection with the lens assembly 23 through the transmission assembly 22, so that the driving assembly 21 can drive the lens assembly 23 to move along the axial direction of the lens assembly 23 through the transmission assembly 22. The positioning mechanism 3 comprises a magnetic positioning member 31 and a positioning detection member 32. The positioning detection member 32 is used to acquire the position of the magnetic positioning member 31 in real time by detecting the magnetic field strength change of the magnetic positioning member 31. The positioning detection member 32 is electrically connected with the driving assembly 21, so that the driving assembly 21 can drive the lens assembly 23 to move or be static according to the position of the magnetic positioning member 31. The shielding mechanism 4 comprises a fixed shielding shell 41 and a sliding shielding shell 42. The fixed shielding shell 41 and the sliding shielding shell 42 enclose a closed space 43. The sliding shielding shell 42 is movably installed in the fixed shielding shell 41 and is used to adjust the size of the closed space 43. The fixed shielding shell 41 is connected with the support 1. The sliding shielding shell 42 is connected with the lens assembly 23. One of the magnetic positioning member 31 and the positioning detection member 32 is arranged in the fixed shielding shell 41, and the other is arranged in the sliding shielding shell 42.

[0046] The technical scheme of the present application detects the magnetic signal of the magnetic positioning member 31 by the positioning detection member 32, thereby obtaining the position of the magnetic positioning member 31, and taking the magnetic positioning member 31 located in the sliding shielding shell 42 and the positioning detection member 32 located in the fixed shielding shell 41 as an example, since the sliding shielding shell 42 is connected with the lens assembly 23, the magnetic positioning member 31, the sliding shielding shell 42 and the lens assembly 23 are synchronously moved, which helps to reduce the detection range of the positioning detection member 32, the positioning detection member 32 obtains the position of the magnetic positioning member 31 in real time, which can be regarded as obtaining the position of the lens assembly 23 in real time, thereby the lens assembly 23 can be directly driven by the driving assembly 21 cooperating with the transmission assembly 22 according to the position of the lens assembly 23, the process of driving the lens assembly 23 to reset and then focusing is saved, and the focusing time is reduced, for example, if the existing lens is in the A position, if the lens is moved to the B position in front of the A position (the route to the B position must pass through the A position), the lens in the A position needs to be reset first, and then the reset lens is moved to the B position; the present application is different, since the present application can obtain the position of the lens assembly 23 in real time, the driving assembly 21 can directly control the lens assembly 23 to move from the A position to the B position, thereby the process of moving the lens assembly 23 from the A position to the starting position and then moving the lens assembly 23 from the starting position to the A position is saved, the focusing process is reduced, and the focusing time is shortened.

[0047] And, since the position detection member 32 can acquire the position of the lens assembly 23 in real time, the position detection member 32 controls the driving assembly 21 to stop running at the same time after detecting that the lens assembly 23 moves to the specified position, so that the lens assembly 23 stays at the position, which improves the accuracy of focusing. Even if the motor rotation phenomenon occurs, the deviation caused by the rotation phenomenon will not be superimposed, thereby improving the accuracy of focusing. For example, the existing technology directly outputs the corresponding control signal according to the position to be reached. If the position to be reached is A, the controller outputs a control signal for rotating the motor two turns, and after the motor rotates two turns, the lens is at the A position. If the motor rotates, the lens will move from the A position to the A1 position behind the A position. At this time, if the lens is not reset, but the corresponding control signal is directly output to the motor according to the preset distance between the A position and the B position, the motor continues to rotate, for example, two turns. Since the motor has rotated before, the starting point of the lens is not the A position but the A1 position. If the motor does not rotate again, the lens cannot move to the B position but moves to the B1 position behind the B position. Once the motor rotates again, the lens moves to the B2 position behind the B1 position. As can be seen, the deviation caused by the rotation of the motor twice is superimposed, which seriously affects the accuracy of focusing. The present application focuses in real time according to the position of the lens assembly 23. When the lens assembly 23 moves to the A position, even if the motor rotates and the lens assembly 23 moves to the A1 position, the position detection member 32 can detect this phenomenon and control the driving assembly 21 to move the lens assembly 23 to correct the deviation. Even if the deviation is not corrected, when the lens assembly 23 needs to move to the B position, the driving assembly 21 will stop only after the position detection member 32 detects that the lens assembly 23 moves to the B position. Whether the motor rotates before or not, since the present application acquires the position of the lens assembly 23 in real time through the position detection member 32, the deviation caused by the motor before will not affect the subsequent movement. The driving assembly 21 will not stop before the lens assembly 23 moves to the B position. Therefore, even if the motor rotates after the lens assembly 23 moves to the B position, it will move to the B1 position (assuming that the displacement of the lens caused by each rotation is the same) based on the B position. The deviation caused by the rotation of the motor twice will not be superimposed. Therefore, compared with the focusing of the prior art, the focusing accuracy is higher in the case of multiple continuous focusing. Since the deviation caused by the rotation of the motor in the embodiment of the present application is at most only once and will not be superimposed, it can be basically ignored.

[0048] Furthermore, the embodiment sets the fixed shielding shell 41 and the sliding shielding shell 42, and sets the magnetic positioning member 31 and the positioning detection member 32 in the closed space 43, thereby reducing the interference of the external magnetic field on the positioning detection member 32, improving the accuracy of the positioning detection member 32, i.e. the positioning detection member 32 can more accurately obtain the position of the lens assembly 23, so as to more accurately adjust the position of the lens assembly 23, thereby further improving the accuracy of focusing. The materials of the fixed shielding shell 41 and the sliding shielding shell 42 can be copper, aluminum or tinned steel, which are not limited herein. It should be noted that the magnetic positioning member 31 is arranged in the fixed shielding shell 41, and the positioning detection member 32 is arranged in the sliding shielding shell 42, which still has the beneficial effects described above, and the principle is basically the same as the above, which will not be repeated here. In addition, the magnetic positioning member 31 and the positioning detection member 32 can be realized by using existing magnetic members and existing magnetic inductors.

[0049] Please refer to Figure 2 and Figure 3 In an embodiment, the transmission assembly 22 includes a focusing lens barrel 221 and a focusing member 222. The focusing lens barrel 221 is connected with the support 1, and the focusing member 222 is sleeved on the periphery of the focusing lens barrel 221 and can rotate relative to the focusing lens barrel 221. The focusing lens barrel 221 is provided with a guide hole 2211 extending along the axial direction of the lens assembly 23. The focusing member 222 is provided with a screw adjusting hole 2221. The lens assembly 23 includes a lens body 231 and a guide pin 232 connected with each other. The sliding shielding shell 42 is connected with the lens body 231. The guide pin 232 penetrates through the guide hole 2211 and the screw adjusting hole 2221. The driving assembly 21 is in transmission connection with the focusing member 222, so that the driving assembly 21 can drive the focusing member 222 to rotate relative to the focusing lens barrel 221, and the focusing member 222 can also drive the lens body 231 to move through the guide pin 232. The driving assembly 21 drives the focusing member 222 to rotate relative to the focusing lens barrel 221, so that the hole wall of the moving screw adjusting hole 2221 pushes the guide pin 232 to move in the guide hole 2211, and then the guide pin 232 drives the lens body 231 to move along the axial direction, so as to adjust the position of the lens body 231. It should be noted that the sliding shielding shell 42 and the lens body 231 can be directly connected, or connected through a connecting column or a connecting rod or other structural members, which are not limited herein.

[0050] Please refer to Figure 2 and Figure 3In an embodiment, the transmission assembly 22 further comprises a gear 223 and an arc-shaped rack 224, the driving assembly 21 comprises a driving motor, the positioning detection member 32 is electrically connected with the driving motor, the driving motor is connected with the support 1, the gear 223 is arranged on the rotating shaft of the driving motor, the arc-shaped rack 224 is arranged on the outer wall of the focusing member 222, the gear 223 is engaged with the arc-shaped rack 224, and the driving motor can drive the focusing member 222 to rotate relative to the focusing lens barrel 221 and simultaneously drive the lens body 231 to move through the gear 223 and the arc-shaped rack 224; the driving motor drives the gear 223 to rotate, the rotating gear 223 drives the arc-shaped rack 224 engaged with the gear 223 to move, the arc-shaped rack 224 drives the focusing member 222 connected with the arc-shaped rack 224 to rotate relative to the focusing lens barrel 221, and the lens body 231 is driven to move through the guide pin 232. In this embodiment, the driving motor drives the lens body 231 through a simple structure, the number of parts is reduced compared with the existing driving form, and the cost is reduced.

[0051] In an embodiment, the inner wall of the focusing lens barrel 221 is attached with the outer wall of the lens body 231, so as to limit the movement of the lens body 231 along the radial direction of the lens body 231 relative to the focusing lens barrel 221. By attaching the inner wall of the focusing lens barrel 221 with the outer wall of the lens body 231, the movement of the lens body 231 along the radial direction of the lens body 231 relative to the focusing lens barrel 221 is prevented, so as to provide a guarantee for the accuracy of focusing.

[0052] In an embodiment, the inner wall of the focusing member 222 is attached with the outer wall of the focusing lens barrel 221, so as to limit the movement of the focusing member 222 along the radial direction of the lens body 231 relative to the focusing lens barrel 221. By attaching the inner wall of the focusing member 222 with the outer wall of the focusing lens barrel 221, the movement of the focusing member 222 along the radial direction of the lens body 231 relative to the focusing lens barrel 221 is avoided, so as to provide a guarantee for the accuracy of focusing.

[0053] In an embodiment, the two hole walls of the guide hole 2211 are both in abutment with the guide pin 232, so as to limit the movement of the lens body 231 along the circumferential direction of the lens body 231 relative to the focusing lens barrel 221. The two hole walls of the guide hole 2211 are both in abutment with the guide pin 232, so as to limit the movement of the guide pin 232 along the extension direction of the guide hole 2211, limit the rotation of the guide pin 232 relative to the focusing lens barrel 221, and further limit the movement of the lens body 231 connected with the guide pin 232 along the circumferential direction of the lens body 231 relative to the focusing lens barrel 221, so as to provide a guarantee for the accuracy of focusing.

[0054] In an embodiment, the number of guide holes 2211 is at least two, the at least two guide holes 2211 are arranged at intervals along the circumference of the focusing lens barrel 221, the number of screw adjustment holes 2221 is consistent with and one-to-one corresponds to the number of guide holes 2211, and the number of guide pins 232 is consistent with and one-to-one corresponds to the number of guide holes 2211. By arranging two or more guide holes 2211, and arranging the number of screw adjustment holes 2221 consistent with and one-to-one corresponding to the number of guide holes 2211, and arranging the number of guide pins 232 consistent with and one-to-one corresponding to the number of guide holes 2211, when one of the guide pins 232 fails, another guide pin 232, and the guide hole 2211 and the screw adjustment hole 2221 matched therewith can still guarantee the accuracy of focusing. It should be noted that the focusing member 222 is a cylindrical structure, which can be a circular cylinder or a square cylinder, and is not limited here.

[0055] Please refer to Figures 5 to 6 In an embodiment, the transmission assembly 22 includes a focusing lens barrel 221 connected with the bracket 1, the focusing lens barrel 221 is provided with guide holes 2211 extending along the axial direction of the lens assembly 23, the lens assembly 23 includes a lens body 231 and a guide pin 232 connected with each other, the sliding shielding shell 42 is connected with the lens body 231, the focusing lens barrel 221 is sleeved on the lens body 231, the guide pin 232 passes through the guide hole 2211, and the two hole walls of the guide hole 2211 arranged oppositely are both in abutment with the guide pin 232, for limiting the movement of the lens body 231 along the circumference of the lens body 231 relative to the focusing lens barrel 221, and the driving assembly 21 is in transmission connection with the guide pin 232, so that the driving assembly 21 can drive the lens body 231 to move along the axial direction of the lens body 231 through the guide pin 232. The two hole walls of the guide hole 2211 arranged oppositely are both in abutment with the guide pin 232, so as to limit the movement of the guide pin 232 along the extension direction of the guide hole 2211, limit the rotation of the guide pin 232 relative to the focusing lens barrel 221, and further limit the movement of the lens body 231 connected with the guide pin 232 along the circumference of the lens body 231 relative to the focusing lens barrel 221, thereby providing guarantee for the accuracy of focusing. Moreover, the driving assembly 21 of the present embodiment can be a linear driving assembly 21, for example, a screw mechanism, the guide pin 232 is connected with the sliding block of the screw mechanism, and the motor directly drives the screw to rotate, thereby driving the guide pin 232 to move through the sliding block; or a gear 223 and a rack meshing transmission form can be adopted, the rack is linear and is connected with the guide pin 232, and the gear 223 is connected with the rotating shaft of the motor. The form of the driving assembly 21 is not limited here.

[0056] In an embodiment, the inner wall of the focusing lens barrel 221 is in abutment with the outer wall of the lens body 231, for limiting the movement of the lens body 231 along the radial direction of the lens body 231 relative to the focusing lens barrel 221; by setting the inner wall of the focusing lens barrel 221 in abutment with the outer wall of the lens body 231, the movement of the lens body 231 along the radial direction of the lens body 231 relative to the focusing lens barrel 221 is prevented, thus ensuring the accuracy of focusing.

[0057] In an embodiment, the number of the guide holes 2211 is at least two, the at least two guide holes 2211 are arranged in a circumferential direction of the focusing lens barrel 221, and the guide pins 232 are arranged in one-to-one correspondence with the number of the guide holes 2211. By setting two or more guide holes 2211, and arranging the screw adjusting holes 2221 in one-to-one correspondence with the number of the guide holes 2211, and arranging the guide pins 232 in one-to-one correspondence with the number of the guide holes 2211, when one of the guide pins 232 fails, another guide pin 232, as well as the guide hole 2211 and the screw adjusting hole 2221 matched therewith, can still ensure the accuracy of focusing.

[0058] Please refer to Figure 8 and Figure 10In an embodiment, the automatic focusing device 100 further comprises a calibration mechanism 5, the calibration mechanism 5 comprising an adjusting piece 51 and an elastic piece 52; the magnetic positioning piece 31 is located in the sliding shielding shell 42 and movably connected with the sliding shielding shell 42, the positioning detection piece 32 is located in the fixed shielding shell 41 and fixedly connected with the fixed shielding shell 41, one end of the adjusting piece 51 is located outside the sliding shielding shell 42, the other end of the adjusting piece 51 is located in the sliding shielding shell 42 and abuts against the magnetic positioning piece 31, the elastic piece 52 is located in the sliding shielding shell 42, one end of the elastic piece 52 is connected with the magnetic positioning piece 31, the other end of the elastic piece 52 is connected with the sliding shielding shell 42, the adjusting piece 51 is movably installed in the sliding shielding shell 42, so that the adjusting piece 51 and the elastic piece 52 can drive the magnetic positioning piece 31 to reciprocate along the axial direction of the lens assembly 23.The inventor has found that due to the manufacturing and installation errors of the lens body 231 and the production and manufacturing errors of the lens on the lens body 231, even if the magnetic positioning member 31 and the positioning detection member 32 are added to obtain the position of the lens body 231 in real time, different batches of lens bodies 231 or different lens bodies 231 produced in the same batch have some unavoidable errors in shape and installation position, and the lens on the lens body 231 also has some unavoidable manufacturing and installation errors, so that even if the magnetic positioning member 31 and the positioning detection member 32 are used to adjust the position of the lens body 231, the focusing effect obtained is uneven and difficult to unify. In order to eliminate the interference caused by these errors, the calibration mechanism 5 is added, and specifically, the position of the magnetic positioning member 31 is adjusted by the adjusting member 51, so as to eliminate the above-mentioned errors. For example, if the lens body 231 needs to move from the starting position to the ideal focusing position, the position corresponds to a distance information, assuming that the distance information is X, the positioning detection member 32 stops the driving assembly 21 after detecting that the magnetic positioning member 31 moves to X, at this time the lens body 231 stops at position A (without considering the motor rotation and other factors), but due to the above-mentioned deviation, the display effect of position A cannot meet the requirements, and the ideal focusing position is at position A1, the distance difference between position A1 and position A is calculated to obtain a value C, and the magnetic positioning member 31 is driven to move a distance C by the adjusting member 51. If position A1 is located in front of position A, the magnetic positioning member 31 is driven to move a distance C backward by the adjusting member 51 to complete the calibration and realize the matching of the distance information X and position A1, that is, if the lens body 231 moves from the starting position to the ideal focusing position, the positioning detection member 32 detects whether the magnetic positioning member 31 moves to position X, if the magnetic positioning member 31 moves to position X, the lens body 231 is located at position A1 instead of position A, that is, the ideal focusing position, realizing the matching of the actual position of the lens body 231 and the preset distance information, thereby eliminating the influence of the above-mentioned deviation and improving the focusing accuracy and the display effect after focusing. It should be noted that after calibrating one position, other positions are also calibrated, so it is not necessary to repeat the calibration process for each position. Similar to the calibration of a watch, after calibrating the time at a certain time on the watch, the subsequent time is correct and does not need to be calibrated at each time. The present application calibrates one position to match the distance information with the actual position of the lens body 231. After the distance information of the position matches the actual position of the lens body 231, other distance information also matches the actual position of the lens body 231, that is, other positions are also calibrated, thereby improving the focusing accuracy. The adjusting member 51 can be a bolt or a stud, which is not limited herein. The elastic member 52 can be a spring or a rubber block, which is not limited herein.

[0059] It should be further noted that the rearward movement of the adjusting member 51 relative to the sliding shielding shell 42 can drive the magnetic positioning member 31 to move rearward, and the rearward movement of the magnetic positioning member 31 compresses the elastic member 52. The forward movement of the adjusting member 51 relative to the sliding shielding shell 42 can drive the magnetic positioning member 31 to move forward under the elastic force generated by the elastic member 52. The elastic member 52 can generate an elastic force to abut the magnetic positioning member 31 against one end of the adjusting member 51 located in the sliding shielding shell 42, so as to adjust the position of the magnetic positioning member 31 in the front-rear direction. As shown in Figure 9 the front-rear direction is parallel to the axial direction of the lens body 231.

[0060] Please refer to Figure 10 In an embodiment, the calibration mechanism 5 further comprises two guide plates 53 arranged at intervals, and a guide channel extending in the axial direction of the lens assembly 23 is formed between the two guide plates 53. The magnetic positioning member 31 is located in the guide channel, and one end of the elastic member 52 abuts against the magnetic positioning member 31. The adjusting member 51 and the elastic member 52 can drive the magnetic positioning member 31 to move reciprocally in the axial direction of the lens assembly 23 in the guide channel. The guide channel formed by the two guide plates 53 can guide the magnetic positioning member 31 to move in a determined direction, so as to ensure the accuracy of the position adjustment of the magnetic positioning member 31, and further provide a guarantee for the accuracy of focusing.

[0061] In an embodiment, the adjusting member 51 is an adjusting screw, the elastic member 52 is a spring, and a threaded hole is formed in the sliding shielding shell 42. The adjusting screw is threadedly connected with the threaded hole, one end of the spring abuts against the magnetic positioning member 31, and the other end of the spring is connected with the sliding shielding shell 42. The position of the magnetic positioning member 31 in the front-rear direction can be adjusted by rotating the adjusting screw. When the magnetic positioning member 31 moves rearward, the spring is compressed. When the adjusting screw moves forward relative to the sliding shielding shell 42, the elastic force generated by the spring drives the magnetic positioning member 31 to move forward and abut against the end of the adjusting screw, so as to adjust the position of the magnetic positioning member 31 in the front-rear direction.

[0062] Please refer to Figure 10In an embodiment, the fixed shielding shell 41 is provided with a first opening 411 communicating with the internal cavity of the fixed shielding shell 41, the sliding shielding shell 42 is provided with a second opening 421 communicating with the internal cavity of the sliding shielding shell 42, and one end of the sliding shielding shell 42 provided with the second opening 421 is inserted into the fixed shielding shell 41 through the first opening 411, so that the internal cavities of the fixed shielding shell 41 and the sliding shielding shell 42 are communicated with each other to form the sealed space 43, and the outer wall of the sliding shielding shell 42 is attached to and slidably matched with the inner wall of the fixed shielding shell 41. Wherein, the attachment of the outer wall of the sliding shielding shell 42 to the inner wall of the fixed shielding shell 41 ensures the stability of the movement of the sliding shielding shell 42.

[0063] According to an embodiment of the present application, the fixed shielding shell 41 is provided with a first opening 411 communicating with the internal cavity of the fixed shielding shell 41, the sliding shielding shell 42 is provided with a second opening 421 communicating with the internal cavity of the sliding shielding shell 42, and one end of the fixed shielding shell 41 provided with the first opening 411 is inserted into the fixed shielding shell 41 through the second opening 421, so that the internal cavities of the fixed shielding shell 41 and the sliding shielding shell 42 are communicated with each other to form the sealed space 43, and the outer wall of the fixed shielding shell 41 is attached to and slidably matched with the inner wall of the sliding shielding shell 42, thereby realizing the synchronous movement of the sliding shielding shell 42 and the lens body 231.

[0064] In an embodiment, the inner wall of the fixed shielding shell 41 is inwardly protruded to form a guide rail (not shown in the figure), the guide rail extends along the axial direction of the lens assembly 23, and the outer wall of the sliding shielding shell 42 is formed with a guide sliding groove (not shown in the figure) slidably matched with the guide rail. By setting the sliding matching of the guide rail and the guide sliding groove, the sliding shielding shell 42 can move along a certain direction, thereby ensuring the stability and accuracy of the direction of the movement of the sliding shielding shell 42.

[0065] The present application also provides a projection light machine (not shown in the figure), which comprises a housing and the automatic focusing device 100 described above, and the bracket 1 is connected with the housing. The specific structure of the automatic focusing device 100 is referred to the above embodiments, and since the projection light machine adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0066] The above description is only an exemplary embodiment of the present application, and does not limit the protection scope of the present application, and any equivalent structural transformation made according to the technical concept of the present application, or direct / indirect application in other related technical fields is included in the protection scope of the present application.

Claims

1. An automatic focusing device characterized by comprising: The automatic focusing device comprises a support, a focusing mechanism, a positioning mechanism and a shielding mechanism. The focusing mechanism comprises a driving assembly, a transmission assembly and a lens assembly. The driving assembly is connected with the support. The driving assembly is in transmission connection with the lens assembly through the transmission assembly. The driving assembly can drive the lens assembly to move along the axial direction of the lens assembly through the transmission assembly. The positioning mechanism comprises a magnetic positioning element and a positioning detection element.

2. The automatic focusing apparatus according to claim 1, wherein The positioning detection element is used to obtain the position of the magnetic positioning element in real time by detecting the magnetic field strength change of the magnetic positioning element. The positioning detection element is electrically connected with the driving assembly. The driving assembly can drive the lens assembly to move or be static according to the position of the magnetic positioning element. The shielding mechanism comprises a fixed shielding shell and a sliding shielding shell. The fixed shielding shell and the sliding shielding shell enclose a closed space. The sliding shielding shell is movably installed in the fixed shielding shell and is used to adjust the size of the closed space. The fixed shielding shell is connected with the support. The sliding shielding shell is connected with the lens assembly. One of the magnetic positioning element and the positioning detection element is arranged in the fixed shielding shell. The other one is arranged in the sliding shielding shell. The automatic focusing device further comprises a calibration mechanism. The calibration mechanism comprises an adjusting element and an elastic element. The magnetic positioning element is located in the sliding shielding shell and is movably connected with the sliding shielding shell. The positioning detection element is located in the fixed shielding shell and is fixedly connected with the fixed shielding shell. One end of the adjusting element is located outside the sliding shielding shell. The other end of the adjusting element is located in the sliding shielding shell and abuts against the magnetic positioning element. The elastic element is located in the sliding shielding shell. One end of the elastic element is connected with the magnetic positioning element. The other end of the elastic element is connected with the sliding shielding shell. The adjusting element is movably installed in the sliding shielding shell. The adjusting element and the elastic element can drive the magnetic positioning element to reciprocally move along the axial direction of the lens assembly. The transmission assembly comprises a focusing lens barrel and a focusing element. The focusing element is sleeved on the periphery of the focusing lens barrel and can rotate relative to the focusing lens barrel. The focusing lens barrel is provided with a guide hole. The guide hole extends along the axial direction of the lens assembly. The focusing element is provided with a spiral adjusting hole. The lens assembly comprises a lens body and a guide pin which are connected with each other. The sliding shielding shell is connected with the lens body. The guide pin penetrates through the guide hole and the spiral adjusting hole. The driving assembly is in transmission connection with the focusing element. The driving assembly can drive the focusing element to rotate relative to the focusing lens barrel. The focusing element can also drive the lens body to move through the guide pin.

3. The automatic focusing apparatus according to claim 2, wherein The transmission assembly further comprises a gear and an arc-shaped rack, the driving assembly comprises a driving motor, the positioning detection member is electrically connected with the driving motor, the driving motor is connected with the support, the gear is arranged on a rotating shaft of the driving motor, the arc-shaped rack is arranged on an outer wall of the focusing member, the gear is engaged with the arc-shaped rack, and the driving motor can drive the focusing member to rotate relative to the focusing lens barrel and simultaneously drive the lens body to move through the gear and the arc-shaped rack. The inner wall of the focusing lens barrel is matched with the outer wall of the lens body, so as to limit the movement of the lens body relative to the focusing lens barrel along the radial direction of the lens body. The inner wall of the focusing member is matched with the outer wall of the focusing lens barrel, so as to limit the movement of the focusing member relative to the focusing lens barrel along the radial direction of the lens body. The two hole walls of the guide hole are both in abutment with the guide pin, so as to limit the movement of the lens body relative to the focusing lens barrel along the circumferential direction of the lens body. The number of the guide holes is at least two, the at least two guide holes are arranged at intervals along the circumferential direction of the focusing lens barrel, the number of the screw adjusting holes is consistent with and corresponds to the number of the guide holes, and the number of the guide pins is consistent with and corresponds to the number of the guide holes.

4. The automatic focusing apparatus according to claim 1, wherein The transmission assembly comprises a focusing lens barrel, the focusing lens barrel is connected with the support, the focusing lens barrel is provided with a guide hole, the guide hole extends along the axial direction of the lens assembly, the lens assembly comprises a lens body and a guide pin which are connected with each other, the sliding shielding shell is connected with the lens body, the focusing lens barrel is sleeved on the lens body, the guide pin penetrates through the guide hole, the two hole walls of the guide hole are both in abutment with the guide pin, so as to limit the movement of the lens body relative to the focusing lens barrel along the circumferential direction of the lens body, and the driving assembly is in transmission connection with the guide pin, so that the driving assembly can drive the lens body to move along the axial direction of the lens body through the guide pin.

5. The automatic focusing apparatus according to claim 4, wherein The inner wall of the focusing lens barrel is matched with the outer wall of the lens body, so as to limit the movement of the lens body relative to the focusing lens barrel along the radial direction of the lens body. The number of the guide holes is at least two, the at least two guide holes are arranged at intervals along the circumferential direction of the focusing lens barrel, and the number of the guide pins is consistent with and corresponds to the number of the guide holes.

6. The automatic focusing apparatus according to any one of claims 1 to 5, wherein The calibration mechanism further comprises two guide plates which are arranged at intervals, a guide channel extending along the axial direction of the lens assembly is formed between the two guide plates, the magnetic positioning member is located in the guide channel, one end of the elastic member in the direction of the adjusting member is in abutment with the magnetic positioning member, and the adjusting member and the elastic member can drive the magnetic positioning member to reciprocate along the axial direction of the lens assembly in the guide channel.

7. The automatic focusing apparatus according to any one of claims 1 to 5, wherein The adjusting member is an adjusting bolt, the elastic member is a spring, a threaded hole is arranged on the sliding shielding shell, the adjusting bolt is in threaded connection with the threaded hole, one end of the spring is in abutment with the magnetic positioning member, and the other end of the spring is connected with the sliding shielding shell.

8. The automatic focusing apparatus according to any one of claims 1 to 5, wherein The fixed shielding shell is provided with a first opening communicating with an inner cavity of the fixed shielding shell, the sliding shielding shell is provided with a second opening communicating with an inner cavity of the sliding shielding shell, one end of the sliding shielding shell provided with the second opening is inserted into the fixed shielding shell through the first opening, so that the inner cavity of the fixed shielding shell and the inner cavity of the sliding shielding shell are communicated to form the closed space, and the outer wall of the sliding shielding shell is matched with and slidably connected to the inner wall of the fixed shielding shell.

9. The automatic focusing apparatus according to claim 8, wherein The inner wall of the fixed shielding shell is inwardly protruded to form a guide rail extending along the axial direction of the lens assembly, and the outer wall of the sliding shielding shell is formed with a guide sliding groove slidably matched with the guide rail.

10. A projection light engine, characterized by, The projection light machine comprises a shell and the automatic focusing device as claimed in any one of claims 1 to 9, and the support is connected with the shell.

Images