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 spectroscopic astronomical telescope and a limiting device thereof, 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 The intermediate rotary sleeve is sleeved in the annular gap and can rotate freely in the annular gap; the central rotary shaft is fixedly provided with a moving contact, the fixed sleeve is fixedly provided with a static contact, and the intermediate rotary sleeve is fixedly provided with an intermediate contact , the moving contact, the static contact and the intermediate contact are all located in the annular gap, the moving contact and the static contact have a preset gap along the axis of the central rotary axis, and the moving contact and the intermediate contact are along the central rotary axis. The axial direction has an overlapping portion, and the intermediate contact can be in contact with the stationary contact when it rotates to a preset position. The limiting device avoids the problem that the optical fiber is broken due to the loss of control of the center-rotating motor.

Description

An optical fiber positioning unit for a spectroscopic astronomical telescope and its limiting device

technical field

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

Background technique

At present, large focal plane spectral survey telescopes (such as my country's LAMOST) use focal plane divisions on the focal plane. Each cell is installed with a two-degree-of-freedom fiber positioning unit, which uses a double rotary motion mechanism (such as patented). CN2344786), as shown in Figure 1. It includes a central rotating shaft 1 and an eccentric rotating shaft 2 with the same length of the rotating arm. The two rotating shafts are driven by a stepping motor after being decelerated by a reducer. Their movement enables the fiber end to reach any position in a circle with a diameter of 33mm. The movement of the two rotating shafts is controlled by the computer sending the drive pulses of the stepping motor to the drive circuit. A total of 4000 identical optical fiber units are installed on the entire LAMOST focal plane, so that when the unit drives the optical fiber end to position, it moves on a small circular plane perpendicular to the axis of the unit.

The double rotary motion mechanism is generally composed of a central rotary part, an eccentric rotary part and an optical fiber holder. The central rotary part drives the central shaft to rotate through the central motor; Position the fiber end face in a flat, small circular area. According to the requirements of the optical fiber positioning principle, the central axis of the unit needs to be rotated 360 degrees to ensure that the optical fiber can be positioned in any direction of the small circle, but this rotation must not be out of control, otherwise if for some reason (such as motor phase loss) the center rotation will fail If the controlled rotation continues without stopping in time, the central rotating part will be entangled with the optical fiber, resulting in serious consequences such as fiber breakage.

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

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an optical fiber positioning unit for a spectral astronomical telescope and a limiting device thereof, so as to solve the problem that the optical fiber is easily broken when the center rotation of the optical fiber positioning unit of the spectral astronomical telescope is out of control.

In order to achieve the above purpose, the present invention provides a limiting device for an optical fiber positioning unit of a spectroscopic astronomical telescope, comprising a fixed sleeve rotatably sleeved on a central rotary shaft, a fixed sleeve formed on the central rotary shaft and the an annular gap between the fixed sleeves and an intermediate rotary sleeve sleeved in the annular gap and capable of rotating freely in the annular gap; a movable contact is fixed on the central rotating shaft, and the fixed sleeve is fixed on A static contact is provided, an intermediate contact is fixed on the intermediate rotary sleeve, the moving contact, the static contact and the intermediate contact are all located in the annular gap, and the moving contact is connected to the annular gap. The static contact has a preset gap along the axial direction of the central rotary shaft, the movable contact and the intermediate contact have an overlapping portion along the axial direction of the central rotary shaft, and the intermediate contact When rotated to a preset position, it can be in contact with the static contact; and the two ends of the moving contact, the two ends of the static contact and the two ends of the intermediate contact are radiated relative to the central axis of rotation The sum of the occupied angles does not exceed 360°.

Preferably, the moving contact includes a return-to-zero moving contact and a positive rotating contact, the return-to-zero moving contact and the positive rotating contact are located on the same side of the intermediate contact, and the static contact is grounded , the return-to-zero moving contact and the positive rotating contact are respectively connected to their respective high-level signals, and the intermediate contact is a conductor. When the zero-returning moving contact or the positive rotating contact is a low-level signal, the driving circuit stops sending the driving signal, and the central motor stops rotating.

Preferably, a fixing ring is fixed on the central rotating shaft, and the movable contact is fixed on the fixing 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 semi-circular cross-section.

Preferably, the static contact is fixed on the fixing sleeve by screws.

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

Preferably, the annular gap is further provided with a central anti-backlash spring axially arranged to eliminate the gap between the gears.

Preferably, one end of the intermediate rotating sleeve is axially limited to the end face of the static contact, and the other end of the intermediate rotating sleeve is provided with an axial limiting portion, and the axial limiting portion is fixed to the center on the rotary axis.

Compared with the description of the background technology, the above-mentioned limiting device for the optical fiber positioning unit of the spectroscopic astronomical telescope includes a fixed sleeve rotatably sleeved on the central rotating shaft, and a ring formed between the central rotating shaft and the fixed sleeve. A gap and an intermediate rotary sleeve that is sleeved in the annular gap and can rotate freely in the annular gap; the central rotary shaft is fixedly provided with a moving contact, the fixed sleeve is fixedly provided with a static contact, and the intermediate rotary sleeve is fixedly provided with a middle The contact, the moving contact, the static contact and the intermediate contact are all located in the annular gap. The axis direction of the rotating shaft has an overlapping portion, and the intermediate contact can be in contact with the static contact when it rotates to a preset position; and the two ends of the moving contact, the two ends of the static contact and the two ends of the intermediate contact are relative to the central rotating shaft The sum of the angles occupied by the radiation does not exceed 360°. In the actual working process of the limiting device, after the moving contact on the central rotary shaft rotates (can be forward rotation or reverse rotation) to contact with the middle contact, the moving contact and the static contact return along the center The axial direction of the rotating shaft has a preset gap, so the two will not directly interfere with each other, and the movable contact and the intermediate contact have an overlapping portion along the axial direction of the central rotating shaft, so the movable contact and the intermediate contact can be in contact with each other. Drive the middle rotary sleeve to rotate. When the middle contact is in contact with the static contact, it is limited and cannot continue to rotate, so as to ensure that the rotation angle of the central rotary shaft is always controlled within the predetermined rotation angle, avoiding the need for the central rotary motor. Loss of control leads to the problem of fiber breakage. In addition, since the sum of the radiation occupation angles of the two ends of the movable contact, the two ends of the static contact and the two ends of the intermediate contact relative to the central rotary axis does not exceed 360°, it can be ensured that the rotation of the central rotary axis can satisfy at least the Rotate 360°.

In addition, the present invention also provides an optical fiber positioning unit for a spectroscopic astronomical telescope, including a limiting device, and the limiting device is the limiting device described in any of the above solutions. Since the above-mentioned limiting device has the above-mentioned technical effects, the optical fiber positioning unit for a spectroscopic astronomical telescope having the above-mentioned limiting device should also have corresponding technical effects, which will not be repeated here.

Description of drawings

Fig. 1 is the working principle schematic diagram of the existing double rotary motion mechanism;

2 is a schematic diagram of the overall structure of an optical fiber positioning unit for a spectroscopic astronomical telescope according to an embodiment of the present invention;

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

Fig. 4 is the A-A sectional structure schematic diagram of Fig. 3 (moving contact and middle contact are not in contact with the position shown);

5 is a schematic diagram of the position of the movable contact when the central rotary shaft is forwardly rotated to the limit position according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of the position of the moving contact detaching from the middle contact during the zero return process of the center rotary shaft provided by the embodiment of the present invention;

7 is a schematic diagram of the position of the moving contact in contact with the other side of the intermediate contact during the process of returning to zero of the central rotary shaft according to an embodiment of the present invention;

8 is a schematic diagram of the moving contact driving the intermediate contact to return to the zero position in the process of returning to zero of the central rotary shaft according to an embodiment of the present invention.

In Figures 1-8 above,

Center rotary shaft 1, eccentric rotary shaft 2, fixed sleeve 3, annular gap 4, intermediate rotary sleeve 5, moving contact 6, static contact 7, intermediate contact 8, zero-returning moving contact 9, positive rotating contact 10 , central motor 11, fixed ring 12, central anti-backlash spring 13, axial limit part 14, central rotary part 15, eccentric rotary part 16, optical fiber frame 17, limit device 18, eccentric motor 19, eccentric anti-backlash spring 20 , screw 21.

Detailed ways

The core of the invention is to provide an optical fiber positioning unit for a spectral astronomical telescope and a limiting device thereof, so as to solve the problem that the optical fiber is easily broken when the center rotation of the optical fiber positioning unit of the spectral astronomical telescope is out of control.

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 below with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 2 to FIG. 8 , a limiting device for an optical fiber positioning unit of a spectroscopic astronomical telescope provided by an embodiment of the present invention includes a fixed sleeve 3 rotatably sleeved on the central rotating shaft 1, formed in The annular gap 4 between the central rotary shaft 1 and the fixed sleeve 3 and the intermediate rotary sleeve 5 sleeved in the annular gap 4 and able to rotate freely in the annular gap 4; the central rotary shaft 1 is fixedly provided with a movable contact 6, A static contact 7 is fixed on the fixed sleeve 3, and an intermediate contact 8 is fixed on the intermediate rotary sleeve 5. The moving contact 6, the static contact 7 and the intermediate contact 8 are all located in the annular gap. The static contact 7 has a preset gap along the axial direction of the central rotary shaft 1 (it should be noted here that, in general, the preset gap needs to be designed to a smaller preset gap value, such as 0.1mm. Because the dynamic The gap between the contact and the static contact along the axis of the central rotary shaft is small enough, and when the moving contact contacts the static contact through the intermediate contact, their contact points are almost on a straight line, so that the "Abbé principle" can be basically satisfied. ”, greatly reducing the error of the principle of returning to zero), the movable contact 6 and the intermediate contact 8 have an overlapping portion along the axial direction of the central rotary shaft 1, and the intermediate contact 8 can be rotated to the preset position. and the sum of the radiation occupation angles of the movable contact 6, the stationary contact 7 and the intermediate contact 8 relative to the central axis of rotation 1 does not exceed 360°.

In the actual working process of the limiting device, after the moving contact on the central rotary shaft rotates (can be forward rotation or reverse rotation) to contact with the middle contact, the moving contact and the static contact return along the center The axial direction of the rotating shaft has a preset gap, so the two will not directly interfere with each other, and the movable contact and the intermediate contact have an overlapping portion along the axial direction of the central rotating shaft, so the movable contact and the intermediate contact can be in contact with each other. Drive the middle rotary sleeve to rotate. When the middle contact is in contact with the static contact, it is limited and cannot continue to rotate, thus ensuring that the rotation angle of the central rotary shaft is always controlled within the predetermined rotation angle. The specific process of forward and reverse rotation is as follows: : During reverse (return to zero) operation, the moving contact rotates together with the central rotary shaft. During the rotation, it first touches the intermediate contact set on the intermediate rotary sleeve of the empty sleeve on the central rotary shaft, and then drives the intermediate contact. The rotary sleeve rotates together, and then continues to rotate until the moving contact pushes the intermediate rotary sleeve and the intermediate contact touches the stationary contact, at which time the motor receives the corresponding signal to stop running; The rotating shaft drives the forward rotation to disengage from the intermediate contact on the intermediate rotary sleeve, and the moving contact can continue to rotate until it touches the intermediate contact on the intermediate rotary sleeve on the other side, and then pushes the intermediate rotary sleeve to rotate together, and finally the middle After the contact touches the other side of the static contact, a corresponding signal is sent to the motor, and the motor stops; among them, the function of the middle rotary sleeve is to compensate for the fact that the moving contact cannot turn a full circle due to the geometrical limitation of itself and the static contact. Sorry. It can be seen from the working process of the above-mentioned limiting device that the limiting device avoids the problem that the optical fiber is broken due to the loss of control of the centrally rotating motor. In addition, since the sum of the radiation occupation angles of the two ends of the movable contact, the two ends of the static contact and the two ends of the intermediate contact relative to the central rotary axis does not exceed 360°, it can be ensured that the rotation of the central rotary axis can satisfy at least the Rotate 360°.

In some specific embodiments, the above-mentioned movable contact 6 may specifically include a return-to-zero moving contact 9 and a positive rotating contact 10, and the return-to-zero moving contact 9 and the positive rotating contact 10 are located on the same side of the middle contact 8, and The static contact 7 is grounded, the return-to-zero moving contact 9 and the positive rotating contact 10 are respectively connected to their respective high-level signals, and the intermediate contact 8 is a conductor. When the zero-returning moving contact 9 or the positive rotating contact 10 is a low-level signal, the driving circuit stops sending the driving signal, and the central motor 11 stops rotating at this time. By detecting the level signals of the zero-returning moving contact and the forward rotating contact, it is easy to know whether the center rotary axis is in the zero-returning state or the state of forwardly rotating to the maximum angle when the central motor stops. Of course, it is understandable that if the central motor and the driving torque are small, the electrical zero position may not be set. The circuit stops rotating immediately after detecting that the center motor is blocked.

The specific structure and working process are as follows: the static contact is grounded, the intermediate contact on the intermediate rotary sleeve is suspended in the annular gap in the central rotary part and the focal plane is electrically insulated, but when the intermediate contact is in contact with the static contact and the moving contact at the same time , the static contact and the moving contact can be electrically connected, and the forward and zero-return moving contacts are respectively connected to their respective high-level signals; when zero-returning, the zero-return moving contact first touches the floating middle contact, at this time The potential will not be pulled down until the middle contact is pushed to meet the static contact, and the grounded static contact pulls the high-level return-to-zero moving contact down to a low level through the middle contact, thereby stopping the drive circuit. Drive; in the same way, the positive rotating contact first touches the middle contact and pushes the middle rotary sleeve to rotate forward. At this time, the positive rotating contact is suspended, and the motor will not stop running until the middle contact is pushed to rotate forward from the other. After the direction hits the static contact, the grounded static contact pulls the high-level positive rotating contact down to a low level through the middle contact, so that the drive circuit stops driving, so as to achieve the center rotation axis of the center rotation part. limiting effect.

In some more specific embodiments, a fixed ring 12 is fixedly arranged on the above-mentioned central rotary shaft 1 , and the movable contact 6 is fixed on the fixed ring 12 . Preferably, the movable contact is fixed on the end face of the fixed ring, but of course it can also be fixed on other positions of the fixed ring, such as on the circumference of the fixed ring. By arranging a fixing ring on the central rotary shaft to fix the movable contact, the arrangement and fixing of the movable contact are more convenient and easy to realize.

In a further embodiment, the above-mentioned fixing ring 12 can generally be fixed on the central rotating shaft 1 by means of pins. Of course, it can be understood that the above-mentioned method of fixing with pins is only a preferred example of the fixing method of the fixing ring in the embodiment of the present invention. In the actual application process, other fixing methods commonly used by those skilled in the art can also be used, such as key connection. way etc.

In some more specific embodiments, the structure of the above-mentioned static contact 7 may be a cylindrical body with a semi-circular cross-section. superior. Of course, it should be noted that those skilled in the art should be able to understand that the above-mentioned semi-circular cylindrical body is only a preferred example of the structure and shape of the static contact according to the embodiment of the present invention. According to the actual needs, choose a static contact structure designed with other structural shapes, such as directly installing a fixed pin on the fixed sleeve as a static contact.

In a further embodiment, the above-mentioned fixed sleeve 3 is fixedly provided with a planetary internal gear, and the motor shaft of the central motor 11 mounted on the central rotary shaft 1 is provided with a pinion which meshes with the planetary internal gear. The central rotary shaft 1 is driven to rotate and the central motor 11 to rotate through the combination of the stationary planetary internal gear and the motor pinion. In this way, the setting of the arrangement position of the motor and the gear is more convenient, and the purpose of the reducer can be realized. Of course, it can be understood that the above are only preferred examples of the embodiments of the present invention, and in practical application, the gears can also be combined with other types of reducers. Of course, it can also be reversed. The planetary internal gear is fixed with the central rotary shaft, and the central motor is fixed on the fixed sleeve. At this time, the central motor rotates in place, and the planetary internal gear drives the central rotary shaft to rotate.

In a further embodiment, the annular gap 4 is also provided with a central anti-backlash spring 13 axially arranged to eliminate the gap between the gears. Through the arrangement of the central anti-backlash spring 13, the cooperation between the gears is made tighter, and it is avoided that the clearance affects the accuracy of the rotation transmission. It should be noted that, generally speaking, not only the internal transmission of the central rotary part 15 needs to be arranged with anti-backlash springs, but also for the eccentric rotary part 16, the eccentric anti-backlash springs 20 are also generally arranged inside, which is also used to improve the transmission. Accuracy.

In addition, it should be noted that those skilled in the art should be able to understand that the above-mentioned intermediate rotary sleeve 5 needs to be kept free to rotate only in the annular gap 4, but cannot move axially, so it needs to be axially limited. The specific method of the axial limit structure can be that one end of the intermediate rotary sleeve 5 is axially limited to the end face of the static contact 7, and the other end of the intermediate rotary sleeve 5 is provided with an axial limit portion 14, and the axial limit The position portion 14 is fixed on the central rotary shaft 1 . It should be noted here that the axial limiting portion 14 can be an additional setting kit that is fixed on the central rotary shaft by threads, or can be directly provided with a shoulder on the central rotary shaft 1 to achieve the position limit. In the actual application process, The settings can be selected according to the actual processing convenience and actual needs.

In addition, the present invention also provides an optical fiber positioning unit for a spectroscopic astronomical telescope, comprising a limiting device 18, and the limiting device 18 is the limiting device described in any of the above solutions. Since the above-mentioned limiting device has the above-mentioned technical effects, the optical fiber positioning unit for a spectroscopic astronomical telescope having the above-mentioned limiting device should also have corresponding technical effects, which will not be repeated here.

In addition, it should be noted that those skilled in the art should be able to understand that an optical fiber positioning unit used for a spectroscopic astronomical telescope generally includes a center revolving part 15, an eccentric revolving part 16, and an optical fiber holder 17, wherein The limiting device 18 is arranged at the bottom end of the central revolving part 15, and of course can also be arranged 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 to the eccentric revolving part 16, and the top end of the eccentric revolving part 16 is connected The optical fiber holder 17 is fixed on the optical fiber holder 17 . The eccentric rotary part 16 drives the eccentric rotary shaft 2 to rotate through the deflection motor 19 .

The optical fiber positioning unit and its limiting device for a spectroscopic astronomical telescope provided by the present invention have been described in detail above. It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. For the same and similar parts among the various embodiments, refer to each other Can.

It should also be noted that, herein, terms such as "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion, whereby an article or device comprising a list of elements includes not only those elements, but also Include other elements not expressly listed, or elements inherent to the article or equipment. Without further limitation, an element defined by the phrase "comprising a..." does not preclude the presence of additional identical elements in an article or device that includes the above-mentioned element.

The principles and implementations of the present invention are described herein by using specific examples, and the descriptions of the above embodiments are only used to help understand the core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can also be made to the present invention, and these improvements and modifications also fall within the protection 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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