CN204515246U - High-precision electric control diaphragm device - Google Patents

Abstract

High-precision electric control diaphragm device, including double arc diaphragm, driving mechanism, transmission mechanism, limit switch, controller and base with a circular light opening at the bottom; the driving mechanism is set on the base and connected with the control connected with the device; the transmission mechanism includes a guide rail slider set on the base and a lead screw set parallel to the guide rail slider set on both sides of the circular light opening; the lead screw is set along the power output direction of the drive mechanism, and one end of the lead screw is connected to the drive The mechanism is connected, and the other end is fixed on the side of the base; the double arc diaphragm is set on the guide rail slider pair and the lead screw; the double arc diaphragm is sheet-shaped, and its contour line includes the first arc edge and the second arc edge , the first arc edge and the second arc edge form a trumpet-shaped opening and have a common endpoint; the arc radius of the first arc edge and the second arc edge matches the light aperture of the circular light opening; the limit switch is fixed on Both ends of the guide rail slider pair are connected with the controller, and the height of the limit switch is higher than that of the guide rail slider pair. The utility model has no minimum diaphragm aperture problem and can realize linear adjustment of light intensity.

Description

High-precision electronically controlled aperture device

technical field

The utility model belongs to the technical field of optical adjustment, and relates to an adjustable aperture device, in particular to a high-precision electric control aperture device which has no minimum aperture problem and can realize linear adjustment of light intensity.

Background technique

The star sensor is a high-precision attitude sensor, which uses stars at different positions on the celestial sphere as detection targets to determine the operating attitude of the spacecraft. The star simulator is a simulation device for the star magnitude, spectrum, angular distance and other indicators of starlight, and completes the performance detection and calibration of the star sensor. It is mainly composed of collimator, star point plate, bandpass filter and light source. composition. In the actual test process, the bandpass filter and the star point plate are placed on the focal plane of the collimator, and the infinite star map is simulated after the light source is illuminated.

At present, in China, the color temperature of the simulated star map is adjusted by increasing the number of band-pass filters and light sources, and the brightness (ie magnitude) of the simulated star map is adjusted by adjusting the power of the light source. In the actual test process, adjusting the power of the light source will change the spectrum of the light source, which will lead to changes in the color temperature of the simulated star map, which is inconsistent with the spectrum of celestial bodies and stars, thus introducing test errors. At present, domestic researchers place an adjustable aperture in front of the bandpass filter, and change the brightness of the simulated star map by adjusting the aperture of the aperture instead of adjusting the power of the light source, thereby eliminating the error introduced by the change of the light source spectrum.

Existing iris mechanisms are divided into manual and electronically controlled. Manual iris has low precision, poor repeatability, and cannot control the speed of the adjustable iris. The driving mechanism of the electronically controlled iris usually adopts a driving motor, a worm gear and a worm structure, which have problems such as low transmission accuracy, large friction force and short service life.

Moreover, the existing iris mechanisms all use a circular constricted diaphragm to adjust the light-passing area of the optical system, so there is inevitably a problem that it cannot be completely closed, and the more the number of diaphragms, the smaller the minimum diaphragm aperture. Large, the current smallest aperture can only achieve Φ1mm. In addition, bowl lamp holders are generally used as light sources on the market, and the light intensity distribution is similar to Gaussian distribution. The existing iris mechanism cannot meet the requirement of linear change of light source intensity.

Utility model content

In order to solve the technical problems in the background technology that the light intensity of the Gaussian beam cannot be linearly adjusted, and the circular shrinkage diaphragm cannot be completely closed, so there is a minimum diaphragm aperture, the utility model provides a non-minimum diaphragm aperture problem and A high-precision electronically controlled diaphragm device that can realize linear adjustment of light intensity.

The technical solution of the utility model is:

The utility model provides a high-precision electric control aperture device, which is special in that it includes a double-arc aperture, a driving mechanism, a transmission mechanism, a limit switch, a controller and a circular light opening at the bottom. The base; the drive mechanism is arranged on the base and connected to the controller; the transmission mechanism includes a pair of guide rail sliders arranged on the base and a pair of guide rail sliders arranged on both sides of the circular light opening parallel to the pair of guide rail sliders. Lead screw; the lead screw is arranged along the power output direction of the drive mechanism, one end of the lead screw is connected with the drive mechanism, and the other end is fixed on the side of the base; the double arc-shaped diaphragm is arranged on the guide rail slider pair and the lead screw; The double-arc diaphragm is a sheet-like structure, and its contour line includes a first arc and a second arc, which form a trumpet-shaped opening and have a common end point; the first arc and the second arc The arc radius of the second arc edge matches the light aperture of the circular light opening; the drive mechanism drives the double arc diaphragm through the guide rail slider pair and the lead screw to make the horn-shaped opening relative to the circular light opening Parallel tangential movement; the limit switch is fixed at both ends of the guide rail slider pair and connected with the controller, and the height of the limit switch is higher than that of the guide rail slider pair.

The contour line of the above-mentioned double-arc diaphragm also includes a first straight side, a second straight side and a third straight side; the common endpoint of the first and second arc-shaped sides is located on the perpendicular bisector of the third straight side The trumpet-shaped opening faces away from the third straight side; the other end of the first arc side is connected to the third straight side through the first straight side; the other end of the second arc side is connected to the third straight side through the third straight side Two straight sides are connected.

The above-mentioned first straight side is parallel to the second straight side; the origin is the common end point of the first arc side and the second arc side, the X-axis passes through the origin and is perpendicular to the third straight side, and the line passing through the origin and perpendicular to The straight line of the X-axis is the Y-axis, a rectangular coordinate system is established, the direction close to the horn-shaped opening is the positive direction of the X-axis, and the direction close to the first straight edge is the positive direction of the Y-axis, then the mathematical model of the double-arc aperture is: :

Among them, R is the arc radius of the first arc edge and the second arc edge, is the angle between the line connecting any point on the arc and the origin and the positive direction of the X-axis, and x and y are the coordinates of any point on the first arc side or the second arc side respectively.

The above-mentioned driving mechanism is a stepping motor; the limit switch includes a first photoelectric switch and a second photoelectric switch respectively fixed at both ends of the slider pair of the guide rail; the first photoelectric switch and the second photoelectric switch are respectively connected with the controller.

The guide rail slider pair includes a guide rail and a slider that is arranged on the base through the guide rail and can slide freely on the guide rail; the guide rail and the lead screw are arranged on both sides of the circular light opening in parallel; the double arc light The diaphragm is arranged on the slider and the lead screw; the stepper motor drives the double arc diaphragm through the lead screw and the slider to make the horn-shaped opening move in parallel and tangentially relative to the circular light opening; the first photoelectric switch And the second photoelectric switch is respectively fixed on two ends of the guide rail, and the heights of the first photoelectric switch and the second photoelectric switch are higher than that of the slider.

The guide above is a support type precision linear bearing guide with a running parallelism of 3.5 μm.

The above-mentioned screw includes a screw and a screw nut that is set on the screw and can reciprocate along the screw; the screw is arranged along the power output direction of the stepping motor, one end of the screw is connected with the stepping motor, and the other end is fixedly connected to the The side part of the base; the double arc aperture is fixedly connected to the lead screw nut and the slide block.

The above-mentioned leading screw and the stepping motor are an integral structure.

The supporting member includes a bearing seat and a bearing; the screw is fixedly connected to the side of the base through the bearing and the bearing seat in turn.

The utility model provides a high-precision electric control aperture device, which has the following advantages:

1. Through the tangential movement of the trumpet-shaped opening of the double-arc diaphragm parallel to the circular light-passing opening, the change of the light-passing area is realized, so the double-arc diaphragm can be completely closed, which effectively solves the problem of the circular shrinkage diaphragm. The problem of the minimum aperture of the aperture; the use of double arc apertures can realize the linear adjustment of the light intensity in the Gaussian distribution, which solves the problem of the jumping of the light energy change rate that exists when the circular contraction aperture is adjusted.

2. Through the cooperation of stepping motor, lead screw, guide rail and photoelectric switch, the linear movement, positioning accuracy and stability of the double arc diaphragm can be effectively guaranteed, so as to ensure the high precision of the light transmission area of the entire electronic control diaphragm device Adjustment.

3. The guide rail adopts a support type precision linear bearing guide rail, which is suitable for single-axis movement and has good linearity.

4. The lead screw and stepping motor adopt an integrated structure, which effectively reduces the size of the entire electronically controlled diaphragm device and has a compact structure.

Description of drawings

Fig. 1 is the structural representation of the high-precision electric control aperture device provided by the utility model;

Fig. 2 is a shape model figure of a preferred embodiment of the double arc diaphragm provided by the utility model;

Fig. 3 is the simulation diagram of cutting Gaussian light beam by using the double arc diaphragm provided by the utility model;

Fig. 4 is a comparison graph of the light energy obtained with the moving distance of the diaphragm when using MATLAB to simulate the double-arc diaphragm and the circular contraction diaphragm to cut the Gaussian beam respectively;

Figure 5 is a comparison of the light energy change rate with the moving distance of the diaphragm when using MATLAB to simulate the double-arc diaphragm and the circular contraction diaphragm to cut the Gaussian beam respectively;

in:

1-double arc diaphragm; 101-first arc edge; 102-second arc edge; 103-first straight edge; 104-second straight edge; 105-third straight edge; 2-drive mechanism; 3- Circular light port; 4-base; 5-first photoelectric switch; 6-second photoelectric switch; 7-guide rail; 8-slider; 9-screw; 10-screw nut; 11-bearing seat; 12 - bearing; 13 - cover plate; 14 - Gauss beam.

Detailed ways

Referring to Fig. 1, the utility model provides a high-precision electronically controlled aperture device, which includes a double-arc aperture 1, a driving mechanism 2, a transmission mechanism, a limit switch, a controller, and a circular light opening at the bottom The base 4 of 3; the driving mechanism 2 is arranged on the base 4 and connected with the controller; Lead screw on both sides; the lead screw is set along the power output direction of the drive mechanism 2, one end of the lead screw is connected with the drive mechanism 2, and the other end is fixed on the side of the base 4; the double arc diaphragm 1 is set on the guide rail slider pair and on the lead screw; the double-arc diaphragm 1 is a sheet-like structure, and its contour line includes a first arc edge 101 and a second arc edge 102, and the first arc edge 101 and the second arc edge 102 form a trumpet-shaped opening and have a Common endpoint; the arc radius of the first arc edge 101 and the second arc edge 102 matches the light aperture of the circular light opening 3; the driving mechanism 2 drives the double arc diaphragm 1 through the guide rail slider pair and the lead screw The horn-shaped opening is made to move in parallel and tangentially relative to the circular light opening 3; the limit switch is fixed on both ends of the guide rail slider pair and connected with the controller, and the height of the limit switch is higher than that of the guide rail slider pair.

Preferably, the outline of the double arc diaphragm in the present invention also includes the first straight side 103, the second straight side 104 and the third straight side 105; the common endpoint of the first arc side 101 and the second arc side 102 Located on the perpendicular bisector of the third straight side 105; the trumpet-shaped opening faces away from the third straight side 105; the other end of the first arc side 101 is connected to the third straight side 105 through the first straight side 103; the second arc side 104 The other end and the third straight side 105 are connected through the second straight side 104 .

Preferably, as shown in Figure 2, the first straight side 103 and the second straight side 104 of the outline of the double-arc diaphragm 1 in the utility model are parallel; The common end point is the origin, the straight line passing through the origin and perpendicular to the third straight side 105 is the X-axis, the straight line passing through the origin and perpendicular to the X-axis is the Y-axis, and a rectangular coordinate system is established, and the direction close to the trumpet-shaped opening is the X-axis Positive direction, the direction close to the first straight side 103 is the positive direction of the Y-axis, then the mathematical model of the double-arc aperture is:

Among them, R is the arc radius of the first arc edge and the second arc edge, is the angle between the line connecting any point on the arc and the origin and the positive direction of the X-axis, and x and y are the coordinates of any point on the first arc side or the second arc side respectively.

In order to control the precise position and speed of the double-arc aperture 1, the driving mechanism 2 in the utility model adopts a stepper motor, which has the advantages of high positioning accuracy, good repeatability, high reliability and easy program control. .

In the utility model, the guide rail slider pair includes a guide rail 7 and a slider 8 that is arranged on the base 4 through the guide rail 7 and can slide freely on the guide rail 7; Both sides; the double arc diaphragm 1 is set on the slider 8 and the lead screw; the stepper motor drives the double arc diaphragm 1 through the lead screw and the slider 8 so that the horn-shaped opening is parallel to the circular light opening 3 Tangential movement.

Further, the guide rail 7 in the present utility model is a support-type precision linear bearing guide rail with a running parallelism of 3.5 μm, which is suitable for single-axis movement and has good linearity, and is fixed on the base 4 by screws.

In the utility model, the limit switch includes the first photoelectric switch 5 and the second photoelectric switch 6 respectively fixed on the two ends of the guide rail 7; the first photoelectric switch and the second photoelectric switch are respectively connected with the controller; The aperture 1 is limited, and the heights of the first photoelectric switch 5 and the second photoelectric switch 6 are both higher than the height of the slider 8 . The photoelectric switch has the advantages of fast response speed, high precision, small size, long life, light weight, and is not affected by magnetic field and vibration.

In the utility model, the lead screw includes a screw 9 and a lead screw nut 10 which is sleeved on the screw 9 and can reciprocate along the screw; the screw 9 is arranged along the power output direction of the stepping motor, one end of the screw is connected with the stepping motor, and the other end It is fixedly connected to the side of the base 4 through the bearing 12 and the bearing seat 11 in sequence;

In order to reduce the size of the entire high-precision electronically controlled aperture device and make it compact in structure, the utility model designs the lead screw and the stepping motor into an integrated structure.

The high-precision electric control aperture device provided by the utility model also includes a cover plate 13 fastened on the base 4 to protect the components inside the entire high-precision electric control aperture device.

The working process of the utility model is: the lead screw stepping motor receives the signal from the controller to drive the lead screw to rotate, the double arc aperture 1 moves together with the lead screw nut 10 and the slider 8, and the double arc aperture 1 moves back and forth Complete the change of the light passing area, and then complete the control of the radiant flux of the light source.

Next, compare the double-arc aperture provided by the utility model with the existing circular shrink aperture:

Assume that the radius of the Gaussian beam is 25 mm, the change rate of the double-curved aperture and the circular constricted aperture are both 5 mm/step, the amplitude A of the spatial amplitude distribution of the Gaussian beam is A=100, and the beam waist of the Gaussian beam is ω ₀ =80. Using MATLAB to simulate the Gaussian beam 14 cut by the double-arc diaphragm (as shown in FIG. 3 ) and the Gaussian beam 14 cut by the circular shrinking diaphragm, the curve relationship between the light energy and the moving distance of the diaphragm is obtained (as shown in FIG. 4 ). It can be seen from Figure 4 that the travel of the double arc diaphragm from fully open to fully closed is 68.3mm, and the travel of the circular retractable diaphragm from fully open to fully closed is 49mm (the minimum aperture of the diaphragm can only be Φ1mm).

It can be seen from Figure 4 and Figure 5 that due to the minimum aperture problem, the circular constricted diaphragm cannot be completely closed, and 1.3% of the light energy will remain in the end; due to the limitation of the number of circular constricted diaphragms, the circular constricted diaphragm cuts Gaussian The beam process is approximately a polygonal contraction process, and there is inevitably a jump in the rate of change of light energy, and the maximum rate of change of light energy is 1.9%.

For the double-arc diaphragm provided by the utility model, it can be seen from Fig. 4 and Fig. 5 that the light energy changes linearly with the moving distance of the double-arc diaphragm, and the maximum value of the light energy change rate is 1.4%, and there is no light energy change Speed jumping problem. Therefore, the double-arc aperture provided by the utility model can effectively solve the problems of the minimum aperture of the aperture and the Gaussian distribution of the bowl light intensity, and can realize the linear adjustment of the light intensity.

In the utility model, the change of the light-passing area is realized by the trumpet-shaped opening of the double-arc diaphragm 1 parallel to the circular light-passing port 3 tangentially moving, so that the double-arc diaphragm can be completely closed, effectively solving the circular The problem of the minimum aperture of the circular constricted diaphragm; moreover, the use of double arc-shaped diaphragms can realize the linear adjustment of the light intensity in the Gaussian distribution, which solves the jump of the light energy change rate that exists when the circular constricted diaphragm is adjusted. question.

In addition, through the cooperation of stepping motors, lead screws, guide rails and photoelectric switches, the linear movement, positioning accuracy and stability of the double-arc diaphragm can be effectively guaranteed, thereby ensuring the high efficiency of the entire electric control diaphragm device for the light transmission area. Precision adjustment.

Claims (9)

1. A high-precision electronically controlled aperture device is characterized in that: it includes a double-arc aperture, a drive mechanism, a transmission mechanism, a limit switch, a controller and a base with a circular light opening at the bottom; The driving mechanism is arranged on the base and connected with the controller; the transmission mechanism includes a pair of guide rail sliders arranged on the base and lead screws arranged on both sides of the circular light opening in parallel with the pair of guide rail sliders; the lead screw Arranged along the power output direction of the driving mechanism, one end of the screw is connected to the driving mechanism, and the other end is fixed on the side of the base; the double arc diaphragm is arranged on the guide rail slider pair and the lead screw; the double arc diaphragm It is a sheet structure, and its contour line includes a first arc edge and a second arc edge, and the first arc edge and the second arc edge surround a trumpet-shaped opening and have a common end point; the first arc edge and the second arc edge The arc radius matches the light aperture of the circular light opening; the drive mechanism drives the double arc diaphragm through the guide rail slider pair and the lead screw to make the horn-shaped opening move parallel to the circular light opening in a tangential direction ; The limit switch is fixed on both ends of the guide rail slider pair and connected with the controller, the height of the limit switch is higher than the height of the guide rail slider pair. 2. The high-precision electronically controlled aperture device according to claim 1, characterized in that: the contour line of the double-arc aperture also includes a first straight side, a second straight side and a third straight side; The common end point of the first arc side and the second arc side is located on the perpendicular bisector of the third straight side; the trumpet-shaped opening faces away from the third straight side; the other end of the first arc side and the third straight side pass through The first straight sides are connected; the other end of the second arc side is connected to the third straight side through the second straight side. 3. The high-precision electronically controlled diaphragm device according to claim 2, characterized in that: the first straight side is parallel to the second straight side; with the common endpoint of the first arc side and the second arc side as the origin, Take the straight line passing through the origin and perpendicular to the third straight side as the X-axis, and the straight line passing through the origin and perpendicular to the X-axis as the Y-axis to establish a rectangular coordinate system. The direction close to the trumpet-shaped opening is the positive direction of the X-axis, and the direction close to the first The direction of the straight side is the positive direction of the Y axis, then the mathematical model of the double-arc diaphragm is: Among them, R is the arc radius of the first arc edge and the second arc edge, is the angle between the line connecting any point on the arc and the origin and the positive direction of the X-axis, and x and y are the coordinates of any point on the first arc side or the second arc side respectively. 4. The high-precision electronically controlled aperture device according to claim 1, 2 or 3, characterized in that: the driving mechanism is a stepping motor; A photoelectric switch and a second photoelectric switch; the first photoelectric switch and the second photoelectric switch are respectively connected to the controller. 5. The high-precision electric aperture device according to claim 4, characterized in that: the guide rail slider pair includes a guide rail and a slider that is arranged on the base through the guide rail and can slide freely on the guide rail; The guide rail and the lead screw are arranged on both sides of the circular light opening in parallel; the double-arc diaphragm is arranged on the slider and the lead screw; the stepping motor drives the double-arc diaphragm through the lead screw and the slider to make the The trumpet-shaped opening makes parallel and tangential movement relative to the circular light opening; the first photoelectric switch and the second photoelectric switch are respectively fixed at both ends of the guide rail, and the heights of the first photoelectric switch and the second photoelectric switch are higher than the slide The height of the block. 6 . The high-precision electronically controlled aperture device according to claim 5 , wherein the guide rail is a support-type precision linear bearing guide rail with a running parallelism of 3.5 μm. 7. The high-precision electronically controlled aperture device according to claim 6, characterized in that: the lead screw includes a screw and a lead screw nut that is sleeved on the screw and can reciprocate along the screw; The power output direction is set, one end of the screw rod is connected to the stepping motor, and the other end is fixedly connected to the side of the base through a support piece; the double-arc aperture is fixedly connected to the lead screw nut and the slider. 8. The high-precision electronically controlled aperture device according to claim 7, characterized in that: the lead screw and the stepping motor are of an integrated structure. 9 . The high-precision electronically controlled aperture device according to claim 8 , wherein the supporting member includes a bearing seat and a bearing; and the screw is fixedly connected to the side of the base through the bearing and the bearing seat in sequence.