CN110727099A - Optical fiber positioning unit for spectrum astronomical telescope and limiting device thereof - Google Patents

Abstract

The invention discloses an optical fiber positioning unit for a spectrum astronomical telescope and a limiting device thereof, which comprise a fixed sleeve, an annular gap and a middle rotary sleeve, wherein the fixed sleeve is rotatably sleeved on a central rotating shaft; the central rotating shaft is fixedly provided with a moving contact, the fixed sleeve is fixedly provided with a static contact, the middle rotating sleeve is fixedly provided with a middle contact, the moving contact, the static contact and the middle contact are all positioned in the annular gap, the moving contact and the static contact have a preset gap along the axis direction of the central rotating shaft, the moving contact and the middle contact have an overlapping part along the axis direction of the central rotating shaft, and the middle contact can be abutted against the static contact when rotating to a preset position. The limiting device avoids the problem that the optical fiber is broken due to the fact that the center rotating motor is out of control.

Description

Optical fiber positioning unit for spectrum astronomical telescope and limiting device thereof

Technical Field

The invention relates to the technical field of spectrum astronomical telescopes, in particular to an optical fiber positioning unit for a spectrum astronomical telescope and a limiting device thereof.

Background

At present, large focal plane spectrum astronomical telescopes (such as LAMOST in China) adopt focal plane partitions on the focal plane, a two-degree-of-freedom optical fiber positioning unit is installed in each cell, and a double-rotation movement mechanism (such as patent CN2344786) is adopted, as shown in figure 1. The device comprises a central rotating shaft 1 and an eccentric rotating shaft 2 with equal rotating arm length, wherein the two rotating shafts are driven by a stepping motor after being decelerated by a speed reducer, and the end parts of optical fibers can reach any position in a circle with the diameter of 33mm through the movement of the two rotating shafts. The two revolving shafts are controlled by the computer to send the driving pulse of the stepping motor to the driving circuit. A total of 4000 identical optical fiber units are mounted across the LAMOST focal plane, such that the units move on a small circular plane perpendicular to the unit axis as the fiber ends are positioned.

The double-rotary motion mechanism generally comprises a central rotary part, an eccentric rotary part, an optical fiber frame and the like, wherein the central rotary part drives a central shaft to rotate through a central motor; the eccentric rotation part drives the eccentric shaft to rotate through the eccentric motor, so that the optical fiber frame is driven by the two rotations to position the end face of the optical fiber in a plane small circle region. According to the requirement of the optical fiber positioning principle, the central shaft of the unit needs to rotate 360 degrees to ensure that the optical fiber can be positioned in any direction of a small circle, but the rotation must ensure that the optical fiber cannot be out of control, otherwise if the central rotation is uncontrollably rotated all the time and stops in time due to some reason (such as motor phase loss), the central rotation part and the optical fiber are wound together, and the optical fiber is broken and the like.

In summary, how to solve the problem that the optical fiber is easily broken when the central rotation of the optical fiber positioning unit of the spectroscopic astronomical telescope is out of control has become a technical problem that needs to be solved by those skilled in the art.

Disclosure of Invention

The invention aims to provide an optical fiber positioning unit for a spectrum astronomical telescope and a limiting device thereof, which aim to solve the problem that an optical fiber is easy to break when the center of the optical fiber positioning unit of the spectrum astronomical telescope is out of control of rotation.

In order to achieve the above object, the present invention provides a limiting device for an optical fiber positioning unit of a spectrum astronomical telescope, comprising a fixed sleeve rotatably sleeved on a central rotating shaft, an annular gap formed between the central rotating shaft and the fixed sleeve, and a middle rotating sleeve sleeved in the annular gap and capable of freely rotating in the annular gap; the central rotating shaft is fixedly provided with a moving contact, the fixed sleeve is fixedly provided with a static contact, the middle rotating sleeve is fixedly provided with a middle contact, the moving contact, the static contact and the middle contact are all positioned in the annular gap, the moving contact and the static contact have a preset gap along the axis direction of the central rotating shaft, the moving contact and the middle contact have an overlapping part along the axis direction of the central rotating shaft, and the middle contact can be abutted against the static contact when rotating to a preset position; and the sum of the radiation occupied angles of the two ends of the moving contact, the two ends of the static contact and the two ends of the middle contact relative to the central rotating shaft is not more than 360 degrees.

Preferably, the moving contacts include a return-to-zero moving contact and a forward-rotation moving contact, the return-to-zero moving contact and the forward-rotation moving contact are located on the same side of the intermediate contact, the fixed contact is grounded, the return-to-zero moving contact and the forward-rotation moving contact are respectively connected with respective high level signals, the intermediate contact is a conductor, when a driving circuit of a central motor for driving the central rotating shaft receives that the return-to-zero moving contact or the forward-rotation moving contact is a low level signal, the driving circuit stops sending a driving signal, and the central motor stops rotating.

Preferably, a fixed ring is fixedly arranged on the central rotating shaft, and the moving contact is fixed on the fixed ring.

Preferably, the fixing ring is fixed on the central rotating shaft by a pin.

Preferably, the static contact is a cylindrical body with a semicircular section.

Preferably, the stationary contact is fixed on the fixing sleeve by a screw.

Preferably, a planetary internal gear is fixedly arranged on the fixed sleeve, and a pinion meshed with the planetary internal gear is arranged on a motor shaft of a central motor for driving the central rotating shaft.

Preferably, a central anti-backlash spring arranged axially for eliminating the clearance between the gears is further arranged in the annular clearance.

Preferably, one end of the middle rotary sleeve is axially limited on the end surface of the fixed contact, and the other end of the middle rotary sleeve is provided with an axial limiting part which is fixed on the central rotary shaft.

Compared with the introduction content of the background technology, the limiting device for the optical fiber positioning unit of the spectrum astronomical telescope comprises a fixed sleeve which is rotatably sleeved on a central rotating shaft, an annular gap formed between the central rotating shaft and the fixed sleeve, and a middle rotating sleeve which is sleeved in the annular gap and can freely rotate in the annular gap; the central rotating shaft is fixedly provided with a moving contact, the fixed sleeve is fixedly provided with a static contact, the middle rotating sleeve is fixedly provided with a middle contact, the moving contact, the static contact and the middle contact are all positioned in the annular gap, the moving contact and the static contact have a preset gap along the axis direction of the central rotating shaft, the moving contact and the middle contact have an overlapping part along the axis direction of the central rotating shaft, and the middle contact can be abutted against the static contact when rotating to a preset position; and the sum of the radiation occupied angles of the two ends of the moving contact, the two ends of the static contact and the two ends of the middle contact relative to the central rotating shaft is not more than 360 degrees. In the actual working process, the limiting device rotates (can be in positive rotation or reverse rotation) through the movable contact on the central rotating shaft to be in contact with the intermediate contact, the movable contact and the static contact cannot directly interfere with each other because a preset gap is formed between the movable contact and the static contact along the axis direction of the central rotating shaft, and the movable contact and the intermediate contact have an overlapping part along the axis direction of the central rotating shaft, so that the movable contact and the intermediate contact can drive the intermediate rotating sleeve to rotate after being in contact with each other, the intermediate contact and the static contact are limited and cannot continue to rotate, the rotating angle of the central rotating shaft is ensured to be always controlled within a preset rotating angle, and the problem that an optical fiber is broken because the out-of-control motor rotating at the. In addition, the sum of the radiation occupied angles of the two ends of the moving contact, the two ends of the static contact and the two ends of the middle contact relative to the central rotating shaft is not more than 360 degrees, so that the central rotating shaft can rotate at least 360 degrees.

In addition, the invention also provides an optical fiber positioning unit for the spectrum astronomical telescope, which comprises a limiting device, wherein the limiting device is as described in any scheme above. Since the above-mentioned limiting device has the above-mentioned technical effects, the optical fiber positioning unit for the spectrum astronomical telescope with the above-mentioned limiting device should also have corresponding technical effects, which are not described herein again.

Drawings

FIG. 1 is a schematic diagram of the operation principle of a conventional dual-rotation mechanism;

FIG. 2 is a schematic diagram of the overall structure of an optical fiber positioning unit for a spectrum astronomical telescope provided by the embodiment of the present invention;

fig. 3 is a schematic cross-sectional structural view of a limiting device according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view A-A of FIG. 3 (showing the movable contact not in contact with the intermediate contact);

fig. 5 is a schematic diagram illustrating a position of the movable contact when the central rotating shaft rotates forward to an extreme position according to an embodiment of the present invention;

fig. 6 is a schematic diagram illustrating a position of the movable contact separated from the middle contact during the zeroing process of the central rotating shaft according to the embodiment of the present invention;

fig. 7 is a schematic view of the movable contact contacting the other side of the intermediate contact during zeroing of the central rotating shaft according to the embodiment of the present invention;

fig. 8 is a schematic diagram illustrating that the moving contact drives the middle contact to return to zero in the process of returning to zero of the central rotating shaft according to the embodiment of the present invention.

In the above figures 1-8 of the drawings,

the device comprises a central rotating shaft 1, an eccentric rotating shaft 2, a fixed sleeve 3, an annular gap 4, a middle rotating sleeve 5, a movable contact 6, a static contact 7, a middle contact 8, a zero-returning movable contact 9, a positive rotating contact 10, a central motor 11, a fixed ring 12, a central anti-backlash spring 13, an axial limiting part 14, a central rotating part 15, an eccentric rotating part 16, an optical fiber frame 17, a limiting device 18, an eccentric motor 19, an eccentric anti-backlash spring 20 and a screw 21.

Detailed Description

The core of the invention is to provide an optical fiber positioning unit for a spectrum astronomical telescope and a limiting device thereof, which are used for solving the problem that the optical fiber is easy to break when the center of the optical fiber positioning unit of the spectrum astronomical telescope is out of control of rotation.

In order to make those skilled in the art better understand the technical solutions provided by the present invention, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 2-8, the limiting device for an optical fiber positioning unit of a spectrum astronomical telescope according to the embodiment of the present invention comprises a fixed sleeve 3 rotatably sleeved on a central rotating shaft 1, an annular gap 4 formed between the central rotating shaft 1 and the fixed sleeve 3, and an intermediate rotating sleeve 5 sleeved in the annular gap 4 and capable of freely rotating in the annular gap 4; a movable contact 6 is fixedly arranged on the central rotating shaft 1, a fixed contact 7 is fixedly arranged on the fixed sleeve 3, a middle contact 8 is fixedly arranged on the middle rotating sleeve 5, the movable contact 6, the fixed contact 7 and the middle contact 8 are all positioned in an annular gap, and the movable contact 6 and the fixed contact 7 have a preset gap along the axial direction of the central rotating shaft 1 (it needs to be noted that, generally, the preset gap needs to be designed into a smaller preset gap value, such as 0.1 mm. when the gap between the movable contact and the fixed contact along the axial direction of the central rotating shaft is enough, the contact point of the movable contact and the fixed contact is almost on a straight line when the movable contact is contacted with the fixed contact through the middle contact, so that the Abbe principle can be basically satisfied, the zero return principle error is greatly reduced), and an overlapping part is arranged between the movable contact 6 and the middle, the middle contact 8 can be abutted against the fixed contact 7 when rotating to a preset position; and the sum of the radiation occupied angles of the movable contact 6, the fixed contact 7 and the middle contact 8 relative to the central revolving shaft 1 is not more than 360 degrees.

This stop device is in the actual work in-process, rotate (can also be for corotation) to contact the back with the middle contact through the moving contact on the pivot of center (can also be for the reversal), because moving contact and static contact have the predetermined clearance along the axle center direction of the pivot of center, therefore the two can not direct mutual interference, and moving contact and middle contact have the overlap section along the axle center direction of the pivot of center, consequently, the moving contact can drive middle revolving sleeve to rotate after contacting with the middle contact, by spacing and unable continuation rotation after middle contact and static contact, thereby make the turned angle who has guaranteed the pivot of center control all the time in predetermined turned angle, the concrete process of just reversing does: when the motor runs reversely (returns to zero), the movable contact and the central rotating shaft rotate together, and in the rotating process, the movable contact firstly touches an intermediate contact which is arranged on an intermediate rotating sleeve which is sleeved on the central rotating shaft in an empty way, then the intermediate rotating sleeve is driven to rotate together, and then the movable contact continues to rotate until the movable contact pushes the intermediate rotating sleeve and the intermediate contact to touch a fixed contact, and at the moment, the motor stops running after receiving a corresponding signal; the moving contact is driven by the central rotating shaft to rotate forward and is separated from the middle contact on the middle rotating sleeve, the moving contact can rotate until the moving contact touches the middle contact on the middle rotating sleeve on the other side, then the middle rotating sleeve is pushed to rotate forward, and finally the middle contact touches the other side of the fixed contact and sends a corresponding signal to the motor, and the motor stops rotating; the middle rotary sleeve has the function of compensating the defect that the moving contact cannot rotate a whole circle due to the limitation of the geometric dimensions of the moving contact and the static contact. According to the working process of the limiting device, the limiting device avoids the problem that the optical fiber is broken due to the fact that the center rotating motor is out of control. In addition, the sum of the radiation occupied angles of the two ends of the moving contact, the two ends of the static contact and the two ends of the middle contact relative to the central rotating shaft is not more than 360 degrees, so that the central rotating shaft can rotate at least 360 degrees.

In some specific embodiments, the movable contact 6 may specifically include a return-to-zero movable contact 9 and a forward rotating contact 10, the return-to-zero movable contact 9 and the forward rotating contact 10 are located on the same side of the intermediate contact 8, and the stationary contact 7 is grounded, the return-to-zero movable contact 9 and the forward rotating contact 10 are respectively connected to respective high level signals, the intermediate contact 8 is a conductor, when a driving circuit of a central motor 11 for driving the central rotating shaft 1 receives that the return-to-zero movable contact 9 or the forward rotating contact 10 is a low level signal, the driving circuit stops sending a driving signal, and at this time, the central motor 11 stops rotating. By detecting level signals of the return-to-zero moving contact and the positive rotating contact, whether the central rotating shaft is in a return-to-zero state or a state of rotating forwards to a maximum angle when the central motor stops can be conveniently known. It can be understood that if the central motor and the driving torque are small, the zero position may not be set, and when the central rotating shaft and the moving contact thereon drive the middle contact to touch the static contact, the central motor is locked, and the driving circuit stops rotating immediately after detecting the locked rotation of the central motor.

The concrete structure and the working process are as follows: the static contact is grounded, the middle contact on the middle rotary sleeve is suspended in the annular gap in the central rotary part and is electrically insulated from the focal plane, but when the middle contact is simultaneously contacted with the static contact and the moving contact, the static contact and the moving contact can be electrically conducted, and the moving contacts rotating forwards and returning to zero are respectively connected with respective high level signals; when the circuit is in zero return, the zero return moving contact firstly touches a suspended middle contact, and the potential cannot be pulled down at the moment until the middle contact is pushed to touch the static contact, and the grounded static contact pulls down the high-level zero return moving contact into a low level through the middle contact, so that the driving circuit stops driving; in the same way, the positive rotating contact firstly touches the middle contact and pushes the middle rotating sleeve to rotate positively during positive rotation, the positive rotating contact is suspended at the moment, the motor cannot stop running until the middle contact is pushed to rotate positively to touch the static contact from the other direction, and the grounded static contact pulls the positive rotating contact with high level down to low level through the middle contact, so that the driving circuit stops driving, and the limiting effect on the central rotating shaft of the central rotating part is achieved.

In some more specific embodiments, the central revolving shaft 1 is fixedly provided with a fixed ring 12, and the movable contact 6 is fixed on the fixed ring 12. The movable contact is preferably fixed to the end face of the fixed ring, but may of course be fixed at other locations on the fixed ring, for example on the circumference of the fixed ring. The moving contact is fixed by arranging the fixing ring on the central rotating shaft, so that the moving contact is more convenient to set and fix and is easy to realize.

In a further embodiment, the retainer ring 12 may be generally pinned to the central pivot shaft 1. It is understood that the above-mentioned manner of fixing by using the pin is merely a preferable example of the fixing manner of the fixing ring of the embodiment of the present invention, and in the practical application, other fixing manners commonly used by those skilled in the art, such as a manner of key connection, etc., may also be used.

In some more specific embodiments, the stationary contact 7 may be a cylindrical body with a semicircular section, and the cylindrical body may be fixed on the fixing sleeve 3 by a screw 21, or may be fixed on the fixing sleeve by other fixing methods. It should be understood that, those skilled in the art should understand that, the above-mentioned semi-circular cylindrical body is only a preferred example of the structural shape of the stationary contact according to the embodiment of the present invention, and in the practical application, the stationary contact structure may be designed into other structural shapes according to practical requirements, for example, a fixed pin is directly installed on the fixed sleeve to serve as the stationary contact.

In a further embodiment, a planetary internal gear is fixedly provided on the fixing sleeve 3, and a pinion gear engaged with the planetary internal gear is provided on a motor shaft of the center motor 11 mounted on the center rotating shaft 1. The central revolving shaft 1 and the central motor 11 are driven to rotate by the matching mode of the immobile planet internal gear and the motor pinion. Therefore, the arrangement of the motor and the gear arrangement position is more convenient, and the purpose of the speed reducer can be realized. It is understood that the above is only a preferred example of the embodiment of the present invention, and in practical application, the gear may be implemented by matching with other types of speed reducers. The planetary internal gear and the central revolving shaft are fixed together, the central motor is fixed on the fixing sleeve, and then the central motor rotates in situ, and the planetary internal gear drives the central revolving shaft to rotate.

In a further embodiment, a central anti-backlash spring 13 is arranged axially in the annular gap 4 for eliminating the gap between the gears. Through the arrangement of the central anti-backlash spring 13, the matching between the gears is tighter, and the influence of the clearance on the accuracy of the rotation transmission is avoided. It should be noted that, in general, not only the internal transmission of the central rotating portion 15 needs to be provided with the anti-backlash spring, but also the eccentric rotating portion 16 is provided with the eccentric anti-backlash spring 20 therein, so as to improve the accuracy of the transmission.

It should be further noted that, as will be understood by those skilled in the art, the intermediate rotating sleeve 5 needs to be kept to be capable of freely rotating only in the annular gap 4, but not to be capable of axially moving, so that it needs to be axially limited, and the axial limiting structure may be implemented in such a manner that one end of the intermediate rotating sleeve 5 is axially limited to the end surface of the stationary contact 7, the other end of the intermediate rotating sleeve 5 is provided with an axial limiting portion 14, and the axial limiting portion 14 is fixed on the central rotating shaft 1. It should be noted here that the axial limiting portion 14 may be an additional set fixed on the central rotating shaft through a thread, or may be a shoulder directly provided on the central rotating shaft 1 to achieve limiting, and in the actual application process, the axial limiting portion may be selectively provided according to the convenience of actual processing and the actual requirements.

In addition, the invention also provides an optical fiber positioning unit for the spectrum astronomical telescope, which comprises a limiting device 18, wherein the limiting device 18 is the limiting device described in any one of the above schemes. Since the above-mentioned limiting device has the above-mentioned technical effects, the optical fiber positioning unit for the spectrum astronomical telescope with the above-mentioned limiting device should also have corresponding technical effects, which are not described herein again.

Besides, it should be noted that those skilled in the art should understand that the optical fiber positioning unit for the spectrum astronomical telescope generally comprises a central revolving part 15, an eccentric revolving part 16, and an optical fiber holder 17, wherein the position-limiting device 18 is disposed at the lowest end of the central revolving part 15, but may be disposed at other positions of the central revolving part, such as the front end of the central revolving part, the top end of which is connected with the eccentric revolving part 16, the highest end of the eccentric revolving part 16 is connected with the optical fiber holder 17, and the optical fiber is fixed on the optical fiber holder 17. The eccentric rotary part 16 drives the eccentric rotary shaft 2 to rotate by a yaw motor 19.

The optical fiber positioning unit for the spectrum astronomical telescope and the limiting device thereof provided by the invention are described in detail above. It should be noted that, in the present specification, the embodiments are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

It is also noted that, in this document, terms such as "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in an article or device that comprises the element.

The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the core concepts of the present invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims (10)

1. A limiting device for an optical fiber positioning unit of a spectrum astronomical telescope is characterized by comprising a fixed sleeve (3) which is rotatably sleeved on a central rotating shaft (1), an annular gap (4) formed between the central rotating shaft (1) and the fixed sleeve (3) and a middle rotating sleeve (5) which is sleeved in the annular gap (4) and can freely rotate in the annular gap (4); a movable contact (6) is fixedly arranged on the central rotating shaft (1), a fixed contact (7) is fixedly arranged on the fixed sleeve (3), a middle contact (8) is fixedly arranged on the middle rotating sleeve (5), the movable contact (6), the fixed contact (7) and the middle contact (8) are all positioned in the annular gap, a preset gap is formed between the movable contact (6) and the fixed contact (7) along the axis direction of the central rotating shaft (1), an overlapping part is formed between the movable contact (6) and the middle contact (8) along the axis direction of the central rotating shaft (1), and the middle contact (8) can be abutted against the fixed contact (7) when rotating to a preset position; and the sum of the radiation occupied angles of the movable contact (6), the fixed contact (7) and the middle contact (8) relative to the central rotating shaft (1) is not more than 360 degrees.

2. The limiting device for the optical fiber positioning unit of the spectral astronomical telescope according to claim 1, wherein said moving contact (6) comprises a return-to-zero moving contact (9) and a forward rotating contact (10), said return-to-zero moving contact (9) and said forward rotating moving contact (10) are located on the same side of said intermediate contact (8), and said stationary contact (7) is grounded, said return-to-zero moving contact (9) and said forward rotating moving contact (10) are respectively connected to high level signals, said intermediate contact (8) is a conductor, when a driving circuit of a central motor (11) for driving said central rotating shaft (1) receives that said return-to-zero moving contact (9) or said forward rotating moving contact (10) is a low level signal, said driving circuit stops sending a driving signal, and said central motor (11) stops rotating.

3. The limiting device for the optical fiber positioning unit of a spectroscopic astronomical telescope according to claim 1 wherein said central rotary shaft (1) is fixedly provided with a fixed ring (12), and said movable contact (6) is fixed to said fixed ring (12).

4. The stop device for the optical fiber positioning unit of a spectroscopic astronomical telescope according to claim 3 wherein said fixed ring (12) is fixed to said central rotation axis (1) by means of pins.

5. The device according to claim 1, characterized in that said stationary contact (7) is a cylindrical body with a semicircular section.

6. The device according to claim 5, characterized in that said stationary contact (7) is fixed to said fixed sleeve (3) by means of screws (21).

7. The limit device for the fiber positioning unit of a spectroscopic astronomical telescope according to any of claims 1 to 6, wherein said fixed sleeve (3) is fixedly provided with a planetary internal gear, and a motor shaft for driving the central motor (11) on said central rotating shaft (1) is provided with a pinion gear engaged with said planetary internal gear.

8. The stop device for the fiber positioning unit of spectroscopic astronomical telescopes according to claim 7, wherein said annular gap (4) is further provided with a central anti-backlash spring (13) arranged axially for eliminating the gap between the gears.

9. The limiting device for the optical fiber positioning unit of the spectroscopic astronomical telescope according to claim 1, wherein one end of the intermediate rotary sleeve (5) is axially limited to the end face of the stationary contact (7), the other end of the intermediate rotary sleeve (5) is provided with an axial limiting part (14), and the axial limiting part (14) is fixed on the central rotary shaft (1).

10. An optical fiber positioning unit for a spectroscopic astronomical telescope, comprising a stop means (18), characterized in that the stop means (18) is according to any of claims 1-9.

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