High-precision dovetail groove type focusing mechanism

Abstract

The embodiment of the invention provides a high-precision dovetail groove type focusing mechanism. In the CCD adjusting process, in order to guarantee stable operation and clear images, a focusing mechanism is designed to be matched with a dovetail groove pair, and clearance elimination processing is designed in the fit clearance of a groove; in order to ensure that the position of the CCD is stable after adjustment is completed, an attaching and tensioning mechanism is designed; meanwhile, in order to eliminate assembly stress caused by different shafts, a coupling is arranged in the transmission mechanism. According to the invention, the front and back micro-adjustment of the CCD target surface is realized, the servo motor is adopted to drive the dovetail groove sub-groove plate to smoothly move on the mother groove plate, and stable and effective focusing is realized in combination with various anti-clamping stagnation and gap eliminating mechanisms.

Description

Technical Field

[0001] The present application relates to the technical field of long focal length continuous zoom television sensors, and in particular to a high-precision dovetail groove focusing mechanism. Background Art

[0002] During the use of the continuous zoom TV sensor, when the distance of the observed object is different, zoom conversion is required to achieve the purpose of magnifying the distant target or expanding the observation field of view; due to certain errors in processing and assembly, as well as the influence of changes in meteorological conditions, the image after the zoom conversion may need further micro-focusing, and this focusing mechanism is achieved by micro-moving the charge-coupled device (CCD) target surface.

[0003] Since the slight movement of the CCD target surface has a great influence on the imaging quality, how to ensure that the motion mechanism is smooth, without jamming or shaking, and that the focal plane position is stable during the focusing process is a problem that needs to be solved in the design process of the focusing mechanism. Summary of the invention

[0004] The invention aims to realize the front and rear micro-adjustment of the CCD target surface, adopt a servo motor to drive the smooth movement of the dovetail groove sub-groove plate on the mother groove plate, and combine a variety of anti-stuck and gap elimination mechanisms to realize stable and effective focusing.

[0005] The embodiment of the present invention provides a high-precision dovetail groove focusing mechanism, the focusing mechanism 5 comprising:

[0006] The CCD target surface 502 is mounted on a bracket 504 through a front pressure strip 501 and a rear pressure strip 503;

[0007] The bracket 504 is fixed to the stand 511 by screws;

[0008] The stand 511 is fixed to the dovetail groove plate 516 by screws;

[0009] The dovetail slot plate 516 cooperates with the dovetail slot plate 506 through the dovetail slot to achieve relative smooth movement between the two. A limit paddle 508 is installed at the front end of one side of the dovetail slot plate 516.

[0010] A front limit switch 509 and a rear limit switch 507 are installed on the dovetail groove plate 506;

[0011] A motor mounting frame 505 is installed at the rear end of the dovetail groove plate 506, and a servo motor 519 is arranged on the motor mounting frame 505. The servo motor 519 is connected to a transmission screw 514 through a coupling 512. The transmission screw 514 cooperates with a transmission nut 513, and the transmission nut 513 is installed on the stand 511.

[0012] A tightening screw 518 is fixed at the bottom of the motor mounting frame 505 . The tightening screw 518 cooperates with a tightening spring 517 . The tightening spring 517 is fixedly connected to the dovetail groove sub-plate 516 .

[0013] In some embodiments, after the servo motor 519 is powered on, the motor shaft rotates through the coupling 512 to drive the transmission screw 514 to rotate, thereby driving the transmission nut 513 to move forward and backward, and the transmission nut 513 drives the dynamic stand 511 and the CCD target surface 502 mounted thereon to move forward and backward together.

[0014] In some embodiments, when the movement reaches the limit position, the limit paddle 508 will correspondingly press the front limit switch 509 or the rear limit switch 507, and the servo motor 519 will be powered off and stopped after receiving the feedback signal.

[0015] In some embodiments, the tension spring 517 is always in a tensioned state to keep the CCD target surface 502 stable at any position.

[0016] In some embodiments, the coupling 512 is used to eliminate the transmission stress caused by the misalignment between the servo motor 519 and the transmission screw 514 .

[0017] In some embodiments, a matching round rod is designed at the bottom of the transmission nut 513 to eliminate the non-parallelism between the transmission screw 514 and the movement direction of the dovetail slot pair, and to achieve a flexible gap fit with the round hole of the dovetail slot sub-plate 516.

[0018] In some embodiments, a cotter pin 520 is installed at the lower end of the transmission nut 513 to prevent the transmission nut 513 from being disengaged from the dovetail slot sub-plate 516.

[0019] In some embodiments, a gap-eliminating modified screw 515 is provided between the dovetail slot mother plate 506 and the dovetail slot daughter plate 516. The head of the gap-eliminating modified screw 515 is designed with a round head. During installation, gap contact is adopted between the gap-eliminating modified screw 515 and the dovetail slot daughter plate 516.

[0020] In some embodiments, the dovetail groove mother plate 506 and the dovetail groove daughter plate 516 are made of 40Cr steel.

[0021] The embodiment of the present invention provides a long-pitch continuous zoom TV sensor, comprising: a protective glass group 1, a lens cover group 2, a TV outer shell 3, a TV optical lens 4, a rear cover 6 and a focusing mechanism 5 as described in any of the above embodiments;

[0022] The focusing mechanism 5 is installed at the rear end of the television optical lens 4 and on the rear bracket of the television outer shell 3 .

[0023] The beneficial effects of the above embodiments include:

[0024] During the CCD adjustment process, in order to ensure smooth operation and clear images, the focusing mechanism is designed with a dovetail groove pair, and the gap between the grooves is designed with a clearance elimination treatment; to ensure that the position of the CCD is stable after the adjustment is completed, a fitting tensioning mechanism is designed; at the same time, to eliminate the assembly stress caused by different axes, a coupling is provided in the transmission mechanism. This invention is to achieve micro-adjustment of the front and rear of the CCD target surface, use a servo motor to drive the smooth movement of the dovetail groove sub-slot plate on the mother groove plate, and combine a variety of anti-jamming and clearance elimination mechanisms to achieve stable and effective focusing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings illustrate generally, by way of example and not limitation, various embodiments discussed herein.

[0026] Figure 1 It is a schematic diagram of the position of the focus mechanism in the continuous zoom lens;

[0027] Figure 2 It is a schematic diagram of the right side structure of the focusing mechanism;

[0028] Figure 3 It is a left view structural diagram of the focusing mechanism;

[0029] Figure 4 It is a schematic diagram of the partial cross-sectional structure of the focusing mechanism from the front view.

[0030] Explanation of symbols:

[0031] 1- protective glass group, 2- lens cover group, 3- TV housing, 4- TV optical lens, 5- focusing mechanism, 6- rear cover, 501- front pressure strip, 502- CCD target surface, 503- rear pressure strip, 504- bracket, 505- motor mounting frame, 506- dovetail groove plate, 507- rear limit switch, 508- limit paddle, 509- front limit switch, 511- stand, 512- coupling, 513- transmission nut, 514- transmission screw, 515- clearance elimination modified screw, 516- dovetail groove plate, 517- tension spring, 518- tension screw, 519- servo motor, 520- cotter pin. DETAILED DESCRIPTION

[0032] In order to enable a more detailed understanding of the features and technical contents of the embodiments of the present application, the implementation of the embodiments of the present application is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present application.

[0033] In the embodiments of the present application, it should be noted that, unless otherwise specified and limited, the term "connection" should be understood in a broad sense. For example, it can be an electrical connection or a connection between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0034] It should be noted that the terms "first\second\third" involved in the embodiments of the present application are only used to distinguish similar objects, and do not represent a specific order for the objects. It is understandable that the specific order or sequence of "first\second\third" can be interchanged where permitted. It should be understood that the objects distinguished by "first\second\third" can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0035] Figure 1 This is a diagram of the composition of a long-pitch continuous zoom TV sensor. Figure 1 As shown, the long-pitch continuous zoom TV sensor comprises a protective glass group 1, a lens cover group 2, a TV outer shell 3, a TV optical lens 4, a focusing mechanism 5 and a rear cover 6.

[0036] The focusing mechanism 5 is installed at the rear end of the television optical lens 4 and on the rear bracket of the television outer shell 3 .

[0037] The composition of the focusing mechanism 5 is as follows: Figure 2 , Figure 3 As shown, the CCD target surface 502 is installed on the bracket 504 through the front pressure strip 501 and the rear pressure strip 503. The bracket 504 is fixedly connected to the stand 511 through screws. The stand 511 is fixedly connected to the dovetail slot plate 516 through screws. The dovetail slot plate 516 cooperates with the dovetail mother slot plate 506 through the dovetail groove to achieve relative smooth movement between the two.

[0038] A limit paddle 508 is installed at the front end of one side of the dovetail slot plate 516, and a front limit switch 509 and a rear limit switch 507 are installed on the dovetail mother slot plate 506; a motor mounting frame 505 is installed at the rear end of the dovetail mother slot plate 506, on which a servo motor 519 is mounted, which is connected to a transmission screw 514 through a coupling 512, and the transmission screw 514 cooperates with a transmission nut 513, and the transmission nut 513 is installed on a stand 511.

[0039] A tensioning screw 518 is fixed at the bottom of the motor mounting frame 505 . The tensioning screw 518 cooperates with a tensioning spring 517 , and the tensioning spring 517 is fixedly connected to the dovetail groove sub-plate 516 .

[0040] Working principle:

[0041] like Figure 2 When the CCD target surface 502 needs to move, the servo motor 519 is energized, and the motor shaft rotates to drive the transmission screw 514 to rotate through the coupling 512, driving the transmission nut 513 to move forward and backward, and the transmission nut 513 drives the supporting frame 511 to move forward and backward together, and the supporting frame 511 drives the bracket 504 and the CCD target surface 502 installed thereon to move forward and backward together.

[0042] When the movement reaches the limit position, the limit paddle 508 will correspondingly press the front limit switch 509 or the rear limit switch 507, and the servo motor 519 will be powered off and stopped after receiving the feedback signal.

[0043] like Figure 3 In order to keep the CCD target surface 502 stable at any position, the tension spring 517 is always in a tensioned state.

[0044] like Figure 3 In order to eliminate the transmission stress caused by the servo motor 519 and the transmission screw 514 being out of axial alignment, a coupling 512 is provided between the two.

[0045] like Figure 4 In order to eliminate the non-parallelism between the transmission screw 514 and the movement direction of the dovetail slot pair, a matching round rod is designed at the bottom of the transmission nut 513 to achieve a flexible gap fit with the round hole of the dovetail slot sub-plate 516, and the matching gap is 0 to 0.03 mm on one side.

[0046] like Figure 4 In order to prevent the transmission nut 513 from being disengaged from the dovetail groove sub-plate 516, a cotter pin 520 is installed at the lower end of the transmission nut 513.

[0047] like Figure 4 In order to ensure smooth fit between the dovetail groove mother plate 506 and the dovetail groove daughter plate 516, matching molding is selected during dovetail groove processing. In order to eliminate the matching gap between the two, a gap elimination modified screw 515 is designed, which is modified from GB / T70 M4*16. Its head adopts a round head design. During installation, it adopts gap contact with the dovetail groove daughter plate 516. The gap elimination modified screw 515 and the dovetail groove mother plate 506 are matched with screw holes and equipped with spring washers. When fixed, thread glue is used to reinforce the matching threads. Here, 243 thread glue can be selected as the thread glue.

[0048] In order to eliminate the influence of thermal deformation on the cooperation between the dovetail groove master plate 506 and the dovetail groove daughter plate 516, the materials of both are made of steel 40Cr which is relatively less susceptible to temperature changes.

[0049] Since the dovetail groove pair is a sliding fit, in order to ensure smooth operation, the finish of the mating surface needs to reach 3.2, and lubricating grease is required during assembly.

[0050] The actual use proves that the dovetail groove focusing mechanism operates smoothly and has high reliability. This high-precision dovetail groove focusing mechanism can be promoted and applied to other similar focusing systems.

[0051] The technical solutions described in the embodiments of the present application can be combined arbitrarily without conflict.

[0052] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A high-precision dovetail groove focusing mechanism, characterized in that: The focusing mechanism (5) comprises: A CCD target surface (502) is mounted on a bracket (504) via a front pressure strip (501) and a rear pressure strip (503); The bracket (504) is fixedly connected to the stand (511) by screws; The stand (511) is fixedly connected to the dovetail groove plate (516) by screws; The dovetail slot plate (516) and the dovetail slot plate (506) cooperate with each other through the dovetail slot, so that the two can achieve relative smooth movement. A limit paddle (508) is installed at the front end of one side of the dovetail slot plate (516); A front limit switch (509) and a rear limit switch (507) are installed on the dovetail groove plate (506); A motor mounting frame (505) is installed at the rear end of the dovetail groove plate (506), a servo motor (519) is arranged on the motor mounting frame (505), the servo motor (519) is connected to a transmission screw (514) through a coupling (512), the transmission screw (514) cooperates with a transmission nut (513), and the transmission nut (513) is installed on the stand (511); A tensioning screw (518) is fixed at the bottom of the motor mounting frame (505), the tensioning screw (518) cooperates with a tensioning spring (517), and the tensioning spring (517) is fixedly connected to the dovetail groove sub-plate (516).

2. The focusing mechanism according to claim 1, characterized in that: After the servo motor (519) is powered on, the motor shaft rotates through the coupling (512) to drive the transmission screw (514) to rotate, thereby driving the transmission nut (513) to move forward and backward. The transmission nut (513) drives the dynamic stand (511) and the CCD target surface (502) mounted thereon to move forward and backward together.

3. The focusing mechanism according to claim 1, characterized in that: When the movement reaches the limit position, the limit paddle (508) will correspondingly press the front limit switch (509) or the rear limit switch (507), and the servo motor (519) will be powered off and stopped after receiving the feedback signal.

4. The focusing mechanism according to claim 1, characterized in that: The tension spring (517) is always in a tensioned state to keep the CCD target surface (502) stable at any position.

5. The focusing mechanism according to claim 1, characterized in that: The coupling (512) is used to eliminate the transmission stress caused by the misalignment between the servo motor (519) and the transmission screw (514).

6. The focusing mechanism according to claim 1, characterized in that: The bottom of the transmission nut (513) is designed with a matching round rod for eliminating the non-parallelism between the transmission screw (514) and the movement direction of the dovetail slot pair, and realizing a gap-flexible fit with the round hole of the dovetail slot sub-plate (516).

7. The focusing mechanism according to claim 1, characterized in that: A cotter pin (520) is installed at the lower end of the transmission nut (513) to prevent the transmission nut (513) from being disengaged from the dovetail slot sub-plate (516).

8. The focusing mechanism according to claim 1, characterized in that: A gap-eliminating reforming screw (515) is arranged between the dovetail slot mother plate (506) and the dovetail slot sub-plate (516). The head of the gap-eliminating reforming screw (515) is designed with a round head. During installation, the gap-eliminating reforming screw (515) and the dovetail slot sub-plate (516) are in gap contact.

9. The focusing mechanism according to claim 1, characterized in that: The material of the dovetail groove mother plate (506) and the dovetail groove daughter plate (516) is steel 40Cr.

10. A long-pitch continuous zoom television sensor, characterized in that: include: A protective glass assembly (1), a lens cover assembly (2), a television outer shell (3), a television optical lens (4), a rear cover (6), and a focusing mechanism (5) as claimed in any one of claims 1 to 9; The focusing mechanism (5) is installed at the rear end of the television optical lens (4) and on the rear bracket of the television outer shell (3).

Images