CN1095085C - Fibre-optical unit positioning apparatus for astronomy spectrotelescope - Google Patents

Abstract

The present invention relates to an optical fiber positioning device on a focal plane of an astronomical optical spectrum telescope, which is composed of a rotating motion mechanism and a radial translational motion mechanism, wherein the rotating motion mechanism drives a hollow shaft to rotate within the range of (+/-) 180DEG by a control motor via a decelerating transmission mechanism, and the radial translational motion mechanism drives a parallelogram translational motion mechanism by the control motor via the transmission mechanism, so that a connecting rod board provided with optical fiber heads makes a translational motion in a certain radial direction of the hollow shaft so as to realize the polar coordinate positioning of the optical fiber heads with convenient operation. When the present invention is used in a large-size telescope, a plurality of optical fiber positioning devices are assembled on the same focal plane board so as to simultaneously observe a plurality of celestial bodies; when different sky zones are observed, the optical fiber positioning device can be conveniently and rapidly adjusted.

Description

Optical fiber unit positioning device for astronomical spectroscopic telescope

technical field

The invention relates to the manufacture of a focal plane system of an astronomical spectrum telescope, in particular to an optical fiber positioning device on the focal plane.

Background technique

Optical fiber is the light-receiving element of astronomical spectroscopic telescope. During actual observation, the optical fiber receiving head is aimed at the position of the star image of the celestial body to collect the light of the star image and transmitted to the spectrometer through the optical fiber. Due to the large sky area and the large number of celestial bodies, and the limited aperture and focal area of the telescope, a telescope can only observe a part of the sky area at a time. If you need to change the observation sky area, you need to adjust the position of the optical fiber receiving head so that it corresponds to the position of the celestial body and star image in the new sky area. When the area of the focal plane is fixed, and the observer wants to observe as many star images as possible at the same time, it is necessary to install as many fiber optic heads as possible on the focal plane, which not only requires high position accuracy, but also facilitates adjustment and re- position. This makes the positioning and installation of the optical fiber head highly technically difficult. Now there are two common methods in the world: one is the fixed drilling method, that is, holes are punched on a substrate according to the corresponding positions of the celestial bodies and star images in the sky area to be observed, and then the optical fibers are fixedly installed in these holes. , place the plate on the focal plane of the telescope when observing. The DSS telescope of the University of Chicago in the United States uses this method to install optical fibers. Its shortcoming is that when the observer wants to change the observation sky area, it needs to replace the new optical fiber substrate, which requires a lot of processing. Simultaneously because its hole position is fixed, fine-tuning is very inconvenient. Another method is the magnetic buckle method, that is, using an iron plate as the substrate, a magnetic buckle is set at each position corresponding to the star image of the celestial body, and there is a prism on the upper part of the magnetic buckle, which deflects the light of the star image of the celestial body by 90° ° shot into the optical fiber lying flat on the iron plate, and then transmitted to the spectrometer, the placement of the magnetic buckle head is performed by a delicate robot. The European ESO (European Souotben Obserratory) telescope uses this method to fix the optical fiber. Although this method has the advantage of convenient adjustment, its structure is complex, and each receiving end has an optical fiber dragged on the substrate, so the distribution density should not be too large. Generally, it is only applicable to small optical fiber substrates.

Contents of the invention

The object of the present invention is to provide a kind of optical fiber positioning device that can make the optical fiber receiving head move on the circumference of variable radial size, so that the observer can adjust the position of the optical fiber receiving head in a fixed circular plane, so that Corresponding to different astrological positions.

The purpose of the present invention is achieved in the following ways.

The optical fiber positioning unit device described in the present invention includes a rotary motion mechanism and a radial translation motion mechanism, which are combined to form a polar coordinate motion mechanism. The rotary motion mechanism includes a rotary control motor, a reduction transmission mechanism and a hollow shaft, and the rotation The control motor drives the hollow shaft to rotate in the range of ±180° through the reduction transmission mechanism. The hollow shaft is supported on the focus panel of the telescope, and its axis is perpendicular to the focus panel; the radial translation movement includes translation control motor and parallelogram translation The parallelogram translation mechanism is composed of upper and lower parallel plates, a hinge and a connecting rod plate. One end of the two parallel plates is hinged on the upper end surface of the hollow shaft through a hinge, and the other end of the two parallel plates is hinged through a hinge. On the connecting rod plate, the translation control motor is fixedly installed on the upper end surface of the hollow shaft, and is connected with a reduction transmission mechanism. The reduction transmission mechanism includes a conversion mechanism that converts rotary motion into linear motion, such as screw nut Mechanism, spiral inclined movement mechanism, etc., the final output part of which is fixedly connected to the parallel plate or connecting rod plate in the above-mentioned parallelogram mechanism; the connecting rod plate is provided with a hole for installing the optical fiber head, and the axis of the hole is in line with the The axes of the hollow shaft are parallel, the optical fiber is fixed in the hole, and the optical fiber is led out from the inner hole of the hollow shaft. The hinge is preferably a flexible hinge, and a general-purpose swing hinge can also be used.

In the above-mentioned rotary motion mechanism and radial translation motion mechanism, in order to eliminate the return error in the transmission process and ensure the position accuracy of the optical fiber movement, a gap elimination mechanism commonly used in the prior art can be installed in the transmission mechanism, such as a spring Anti-backlash mechanism, fixed anti-backlash mechanism, etc.

According to the invention, the optical fiber head used for observing celestial bodies and stars rotates along with the hollow shaft and translates under the drive of the parallelogram translation mechanism, so that the receiving end face of the optical fiber receiving head does not deflect. The optical fiber is connected to the spectrometer after passing through the inner hole of the hollow shaft, and basically does not twist and deform with the rotation of the hollow shaft, so this device can ensure that the fiber head is in the best receiving position and has better receiving efficiency; The movement trajectory of the fiber optic head is controlled by two motors, realizing polar coordinate positioning, and there is no blind area in its control area, and it can be precisely positioned at any position. Therefore, when the observer needs to change the observation sky area, he only needs to control two control motors to adjust the optical fiber head to a new observation position for precise positioning, without replacing other devices, which provides convenience for the observer.

The invention can be used in general astronomical spectrum telescopes, and is especially suitable for large-scale astronomical spectrum telescopes. When used in a large-scale astronomical spectroscopic telescope, many unit devices can be assembled on the same focal plate. For example, when 4000 unit devices of the present invention are installed on a spherical focal plane with a diameter of 1.75m, not only can simultaneous observation of 4000 celestial bodies be realized, but also the observer can conveniently and quickly adjust when observing different sky areas. Compared with other positioning installation methods, the present invention has the advantages of high positioning accuracy, fast positioning and low total manufacturing cost.

Description of drawings

Further description will be made below by means of drawings and examples.

Fig. 1 is a schematic diagram of the principle structure of the present invention.

Fig. 2 is a structural schematic diagram of an embodiment of the present invention. This figure is mainly used to express the radial translational motion mechanism.

Detailed ways

In Fig. 1, (1) is the rotation control motor A, (2) is the rotation reduction gear set A, (3) is the hollow shaft, (4) is the bearing, (5) is the focal plate, and (6) is the translation control motor B, (7) is the translation reduction gear set B, (8) is the screw rod, (9) is the nut, (10), (11) are the upper and lower parallel plates, (12) is the connecting rod plate, (13) is Flexible hinge, (14) optical fiber, (15) is fixed support.

As can be seen from Fig. 1, when the rotation control motor A (1) acts, the gear fixed on the hollow shaft is rotated through the rotation reduction gear set A, so that the hollow shaft (3) is rotated. The hollow shaft is installed on the focus plate (5) and supported by the left and right bearings (4). In actual use, a stepping motor can be selected to make it drive forward and reverse according to the control pulse requirements, so that the hollow shaft can operate within ±180° rotation. When the translation control motor B (6) rotates, the translation reduction gear set B (7) drives the screw (8) to rotate, and the nut (9) matched with it is fixedly connected to the upper parallel plate (10), and the upper and lower parallel plates The left and right ends of the plates (10), (11) are respectively connected to the upper end surface of the hollow shaft (3) and the connecting rod plate (12) by four flexible hinges (13), forming a parallel hinge that can perform translational movement relative to the hollow shaft. In the quadrilateral mechanism, when the translation motor B drives the screw to rotate, the connecting rod plate (12) moves in translation along a certain diameter direction of the hollow shaft. The head of the optical fiber (14) is fixed on the connecting rod plate, and the optical fiber is drawn out from the inner hole of the hollow shaft. Its axis moves ±180° in a circle, realizing polar coordinate positioning. The translation control motor B used for translation and the reduction transmission mechanism are supported on a fixed support (15), which is fixedly connected with the upper end surface of the hollow shaft.

Among Fig. 2, (16) is connecting screw, pin, and (17) is floating support, and (18) is pin screw, and (19) is extension spring, and (20) is worm screw, and (21) is worm gear.

In this embodiment, the rotation control motor A (1) drives the hollow shaft to rotate within ±180° through the reducer. The upper end of the hollow shaft (3) has a large step, and one end of the fixed support (15) is fixed on the end face of the step by connecting screws and pins (16), and a shaft pin screw (18) is installed on the fixed support. Floating support, the floating support can rotate around the pin screw relative to the fixed support, and a tension spring (expressed at the end of this figure) is connected between the fixed support and the floating support to eliminate tooth side clearance. Translational stepper motor B (6) is installed on the floating support, a worm (20) is rigidly connected to its output shaft, and a screw (8) is arranged on the fixed support, and the worm wheel (21) is fixed on the screw shaft , the meshing of the worm gear makes the screw (8) rotate, and the nut (9) matched with it is connected to the upper parallel plate (10), one end of the tension spring (19) is connected to the fixed support, and the other end is connected to the upper parallel plate On the board, it is used to eliminate the thread gap in the screw nut transmission. When the translation stepper motor B rotates, the parallelogram mechanism with flexible hinges is pushed to swing through the worm gear and the screw nut transmission mechanism, so that the optical fiber head can be radially translated. sports.

The working process of this embodiment is that according to the star image coordinates of the measured sky area, the computer gives instructions to control the stepping motors A and B respectively, so that the hollow shaft and the parallelogram mechanism move according to the instructions, so that the optical fiber head is moved. Accurately locate at the corresponding coordinate position of the measured star image.

Claims (4)

1. An optical fiber positioning unit device for astronomical spectrum telescopes, comprising a rotary motion mechanism and a radial translation motion mechanism, the two are combined to form a polar coordinate motion mechanism, and the rotary motion mechanism includes a rotary control motor, a reduction transmission mechanism and A hollow shaft, the rotary control motor drives the hollow shaft to rotate in the range of ±180° through the reduction transmission mechanism. The hollow shaft is supported on the focal plate of the telescope, and its axis is perpendicular to the focal plate; the radial translation movement includes a translation control motor and a parallelogram translation mechanism, the parallelogram translation mechanism includes two upper and lower parallel plates and a connecting rod plate, one end of the upper and lower two parallel plates is respectively hinged on the upper end surface of the hollow shaft by a hinge, the two parallel plates The other ends of the two are respectively hinged on the connecting rod plate by hinges. The translation control motor is fixedly installed on the upper end surface of the hollow shaft and connected with a reduction transmission mechanism. mechanism, the final output part of which is fixed on the upper and lower parallel plates of the planar quadrilateral or the connecting rod plate; the connecting rod plate is provided with a hole for installing the optical fiber head, the axis of the hole is parallel to the axis of the hollow shaft, and the optical fiber head is in the It is fixed in the hole, and the optical fiber is led out from the inner hole of the hollow shaft. 2. The optical fiber positioning unit device according to claim 1, characterized in that the hinge used in the plateau translation mechanism is a flexible hinge. 3. The optical fiber positioning unit device according to claim 1 or 2, characterized in that a universal rotary hinge can be used in the parallelogram translation mechanism instead of a flexible hinge. 4. The optical fiber positioning unit device according to claim 1, characterized in that a gap elimination mechanism is arranged in the reduction transmission mechanism.

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