A digital non-magnetic turntable for geomagnetic field vector observation and its adjustment method

Abstract

The present invention discloses a digital non-magnetic turntable for geomagnetic field vector observation and its adjustment method, which includes a conical rotating shaft mechanism, a turntable support, a support adjustment mechanism, a rotating shaft adjustment mechanism, a turntable tabletop, and a level adjustment mechanism. The turntable has small rotation error, high rotation positioning accuracy and repeated positioning accuracy, and the influence on the magnetic field within the working area of the magnetic probe is less than 1 nT. The non-magnetic turntable and its adjustment method can realize the adjustment of the attitude of the component coil in the geomagnetic vector observation device, realize the digital output of the rotation position, and can precisely fine-tune the rotation angle of the conical rotating shaft mechanism through the fine-tuning component. A non-magnetic spring is provided between the tip body and the tip seat to eliminate the positive and negative clearance. During transportation, the conical rotating shaft mechanism and the rotating shaft adjustment mechanism are relatively locked through the locking component, so that the whole turntable is in a locked state, improving the anti-drop ability during transportation. The high-precision digital turntable can also be used for the calibration of multi-axis magnetic sensors and the attitude of component coils, etc.

Description

Technical Field

[0001] The present invention relates to a non-magnetic turntable and an adjustment method thereof, and particularly to a digital non-magnetic turntable for geomagnetic field vector observation and an adjustment method thereof. Background Art

[0002] In geomagnetic vector observation, it can be composed of a scalar magnetometer and an artificial coil system. The coil provides a uniform artificial magnetic field. By measuring the magnitude of the synthetic magnetic field, the magnitude of the geomagnetic field component can be calculated or directly obtained. When in use, the coil is installed on a non-magnetic turntable. After the axis of rotation of the turntable is adjusted to be vertical, by measuring the steering error of the component coil, the attitude of the coil can be adjusted. For example, when measuring the total geomagnetic field F, horizontal component H, and relative magnetic declination D of a proton vector magnetometer, two groups of coils are installed on the turntable. During debugging, first adjust the axis of rotation of the turntable to be vertical, and finely adjust the turntable to align the axis of the bias coil in the magnetic east-west direction. Then, by measuring the steering errors of the horizontal component and magnetic declination, the attitudes of the two groups of coils are adjusted respectively, so that the axis of the compensation coil is vertically downward and the axis of the bias coil is perpendicular to the magnetic meridian. When data anomalies occur in seismic geomagnetic vector observation, it is also necessary to measure the steering difference of the component coil through the turntable to eliminate the observation data anomalies introduced by changes in the coil attitude. In addition, since the observation pier will tilt during long-term observation, it is also necessary to regularly adjust the attitude of the component coil through the turntable. Therefore, the turntable is crucial for the observation of such vector magnetometers, and it is required that the turntable has a small rotation error, high rotational positioning accuracy and repeat positioning accuracy to reduce the swing error of the turntable itself. The turntable also needs to have flexible rotation and rotational fine-tuning functions and a real-time display light function for the rotational position, and has good stability. The turntable should have weak magnetism, and control is required in terms of materials, processing, surface treatment, etc. to ensure that the residual magnetism within the working area of the magnetic probe is less than 1 nT. Such a high-precision turntable is also applied to the calibration of triaxial magnetic sensors and the attitude of component coils, etc. Summary of the Invention

[0003] Object of the Invention: To provide a digital non-magnetic turntable for geomagnetic field vector observation and an adjustment method thereof, which can improve the rotation accuracy of the turntable and facilitate the transportation of the turntable.

[0004] Technical Solution: The digital non-magnetic turntable for geomagnetic field vector observation described in the present invention includes a conical rotating shaft mechanism, a turntable support, a support adjustment mechanism, a rotating shaft adjustment mechanism, a turntable tabletop, and a level adjustment mechanism;

[0005] The conical rotating shaft mechanism is fixedly installed on the turntable support, and the turntable support fixes the conical rotating shaft mechanism; the support adjusting mechanism is installed on the turntable support, and the support adjusting mechanism adjusts the levelness of the turntable support; the turntable surface is installed on the conical rotating shaft mechanism, and the level adjusting mechanism is installed on the turntable surface. The level adjusting mechanism detects the verticality of the rotating shaft of the component coil placed on the turntable surface; the rotating shaft adjusting mechanism is fixed on the turntable surface, and the rotating shaft adjusting mechanism further includes a locking assembly and a fine-tuning assembly. The locking assembly relatively locks the conical rotating shaft mechanism and the rotating shaft adjusting mechanism, and the fine-tuning assembly finely adjusts the rotation angle of the conical rotating shaft mechanism and the turntable surface.

[0006] Further, the conical rotating shaft mechanism includes a conical shaft, a shaft sleeve, a clearance adjusting nut, an encoder, a ball, and a control box; the conical shaft is arranged in the shaft sleeve, the shaft sleeve is fixedly installed on the turntable support, and the clearance adjusting nut is threadedly installed at the lower part of the shaft sleeve; the ball is arranged at the bottom of the conical shaft; the encoder is arranged between the conical shaft and the shaft sleeve, and the encoder is electrically connected to the control box through a cable, and the control box realizes power supply and data display.

[0007] Further, the locking assembly includes a base, an outer shaft sleeve, a socket pin, a ball head screw, a connecting sleeve, a handle rod, a stop block, and a locking handle; the outer shaft sleeve is installed on the outer shaft shoulder of the shaft sleeve, a crescent groove is opened on the inner side of the outer shaft sleeve, and the socket pin is arranged in the crescent groove; one end of the ball head screw is threadedly installed through the outer shaft sleeve and extends into the crescent groove; the stop block is installed through the base, and the base is fixed on the turntable surface; the handle rod is installed in the hole of the stop block, and the locking handle is fixed on the side of the handle rod away from the ball head screw; orthogonal strip-shaped limiting grooves are respectively opened at both ends of the connecting sleeve; cylindrical pins are respectively press-fitted on the relative spherical surfaces of the handle rod and the ball head screw and respectively extend into the corresponding strip-shaped limiting grooves.

[0008] Further, the fine-tuning assembly includes a center seat, a center body, a center pin body, a center pin seat, a center pin rod, and a fine-tuning handle; the center seat and the center pin seat are both fixed on the base, one end of the center body extends into the center seat, and a non-magnetic spring is arranged inside the center seat, and the non-magnetic spring is fixed between the center seat and the center body; the center pin rod is threadedly connected inside the center pin seat, the fine-tuning handle is installed at one end of the center pin rod, one end of the center pin body extends into the center pin rod, and the relative ends of the center body and the center pin body are respectively pressed on both sides of the protruding part of the outer shaft sleeve.

[0009] Further, the support adjusting mechanism includes a support nut and a support adjusting screw; the support nut is installed on the turntable support, the support adjusting screw is threadedly installed on the support nut, and the support adjusting screw is supported on the support block.

[0010] Further, the level adjustment mechanism includes a detection level, a calibration level, and two level adjustment components; the level adjustment component includes a level fixing block and a screw seat; both the level fixing block and the screw seat are fixed on the turntable surface, and the detection directions of the detection level and the calibration level are perpendicular to each other; one side of the detection level and the calibration level is respectively installed on the corresponding level fixing block, and the other side is respectively installed on the corresponding level adjustment screw, and each level adjustment screw is threadedly installed on the corresponding screw seat.

[0011] The present invention also provides an adjustment method for a digital non-magnetic turntable for geomagnetic vector observation, including the following steps:

[0012] Step 1, when installing the turntable, set the support adjustment mechanism on the observation pier and place it in the middle of the observation pier, then place the turntable on the support adjustment mechanism, and then install the used or calibrated component coil on the turntable surface;

[0013] Step 1.1, place the connecting line direction of the two support adjustment screws of the support adjustment mechanism in the magnetic north-south or magnetic east-west direction, and align the center of the turntable with the center of the observation pier;

[0014] Step 1.2, bond the support block of the support adjustment mechanism to the pier surface of the observation pier.

[0015] Step 2, when adjusting the turntable, adjust the level adjustment mechanism and detect the verticality of the axis of rotation of the component coil placed on the turntable surface, so that the axis of rotation of the component coil placed on the turntable surface is in a vertical state. At this time, both the detection level and the calibration level of the level adjustment mechanism are in the centered state;

[0016] Step 2.1, turn the detection level of the level adjustment mechanism to the connecting line direction of the two support adjustment screws of the support adjustment mechanism, and rotate the support adjustment screw of the support adjustment mechanism to adjust the bubble of the detection level to the middle position;

[0017] Step 2.2, rotate the turntable surface by 180°, and adjust half of the deviation of the bubble with the level adjustment screw on one side of the detection level of the level adjustment mechanism, and adjust the other half with the support adjustment screw of the support adjustment mechanism;

[0018] Step 2.3, repeat steps 2.1 and 2.2 until the difference in the bubble reading on the detection level of the level adjustment mechanism in this direction does not exceed 0.2 grids;

[0019] Step 2.4, rotate the turntable surface by 120°, and repeat the above steps 2.1 and 2.2 until the bubble of the detection level of the level adjustment mechanism is in the middle position when the turntable surface rotates to any angle;

[0020] Step 2.5, adjust the leveling screw of the calibration level of the leveling adjustment mechanism, adjust the bubble to the middle, and rotate the turntable tabletop arbitrarily. The bubble of the calibration level of the leveling adjustment mechanism should be in the middle. Otherwise, go back to Step 2.1 to readjust.

[0021] Step 2.6, rotate the turntable tabletop so that the component coil on the turntable tabletop rotates to the normal working azimuth angle.

[0022] Step 3, orient with a compass, set the axis of the vertically placed component coil in the magnetic north-south or magnetic east-west direction, finely adjust the orientation angle through the rotating shaft adjustment mechanism, and make the absolute value of the measured component the minimum. At this time, the orientation of the component coil is the magnetic north-south or magnetic east-west direction.

[0023] When measuring the turning error of the component coil in Step 4, first measure the current orientation angle as the first component value, rotate the turntable by 180°, and then measure the current orientation angle as the second component value. Then the difference between the first component value and the second component value is the turning error of the component coil.

[0024] Step 4.1, at the current observation azimuth angle, measure 5 groups of component data respectively through the component coil device, eliminate the maximum and minimum values among them, and calculate the average value of the remaining 3 groups of data.

[0025] Step 4.2, rotate the turntable tabletop by 180°, measure 5 groups of component data respectively through the component coil device, eliminate the maximum and minimum values among them, and calculate the average value of the remaining 3 groups of data.

[0026] Step 4.3, calculate the difference between the two average values in Step 4.1 and Step 4.2, which is the turning error of the component coil, and it is the component measurement error introduced by the non-coincidence of the axis of half of the component coil rotating shaft and the rotating shaft.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: By adopting a conical rotating shaft mechanism, higher rotational accuracy can be obtained during operation, and the rotational error is small. The encoders are respectively installed on the shaft shoulders at the lower end of the conical surface and in the bottom holes of the shaft sleeves, with high installation accuracy, realizing the digitization of the rotation angle, and obtaining extremely high rotational positioning accuracy and repeat positioning accuracy. When the turntable is working, the conical rotating shaft mechanism with conical surface fit has better stability, which is conducive to the long-term maintenance of the coil attitude. The conical rotating shaft mechanism and the rotating shaft adjusting mechanism are relatively locked through the locking assembly, so that the whole turntable is in a locked state, which is convenient for transporting the turntable, preventing the impact on the turntable during transportation, and improving the anti-drop ability of the turntable during transportation. The rotation angle of the conical rotating shaft mechanism can be precisely fine-tuned through the fine-tuning assembly of the rotation adjusting mechanism. There is a non-magnetic spring between the tip body and the tip seat to eliminate the positive and negative clearances. The turntable can be fine-tuned within a rotation range of less than 1 degree, so as to realize the micro-correction of the bias coil attitude and the correction of the regular geomagnetic declination offset. Brief Description of the Drawings

[0028] Figure 1 is the structural schematic diagram of the turntable;

[0029] Figure 2 is the structural schematic diagram of the conical rotating shaft mechanism;

[0030] Figure 3 is the structural schematic diagram of the rotating shaft adjusting mechanism;

[0031] Figure 4 is Figure 3 the structural schematic diagram at A-A in

[0032] Figure 5 is the structural schematic diagram of the leveling adjusting mechanism;

[0033] Figure 6 is the structural schematic diagram of the support adjusting mechanism;

[0034] Figure 7 is the structural schematic diagram of the fine-tuning assembly. Detailed Embodiments

[0035] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings, but the protection scope of the present invention is not limited to the described embodiments.

[0036] Embodiment 1:

[0037] As Figure 1-7As shown in the figure, the digital non-magnetic turntable for geomagnetic field vector observation disclosed by the present invention includes: a turntable support 2, a support adjustment mechanism, a rotating shaft adjustment mechanism 4, a turntable tabletop 5, and a level adjustment mechanism; the conical rotating shaft mechanism is fixedly installed on the turntable support 2, and the turntable support 2 fixes the conical rotating shaft mechanism; the support adjustment mechanism is installed on the turntable support 2, and the support adjustment mechanism adjusts the levelness of the turntable support 2; the turntable tabletop 5 is installed on the conical rotating shaft mechanism, and the level adjustment mechanism is installed on the turntable tabletop 5. The level adjustment mechanism detects the verticality of the rotating shaft of the component coil placed on the turntable tabletop 5; the rotating shaft adjustment mechanism 4 is fixed on the turntable tabletop 5, and the rotating shaft adjustment mechanism 4 further includes a locking assembly and a fine-tuning assembly. The locking assembly relatively locks the conical rotating shaft mechanism and the rotating shaft adjustment mechanism 4, and the fine-tuning assembly finely adjusts the rotation angle of the conical rotating shaft mechanism and the turntable tabletop 5.

[0038] The locking assembly and the conical rotating shaft mechanism can relatively lock the conical rotating shaft mechanism and the turntable support 2 to achieve the overall locking of the turntable, which is convenient for transporting the turntable. The design of the turntable tabletop 5 facilitates the replacement of the component coil, making it convenient for on-site station observers to install and carry out operation and maintenance. By detecting the verticality of the rotating shaft of the turntable tabletop 5 through the level adjustment mechanism, the attitude accuracy of the component coil is improved. The fine-tuning assembly can precisely fine-tune the angle of the turntable tabletop 5 to obtain a more precise rotation result.

[0039] Furthermore, the conical rotating shaft mechanism includes a conical shaft 101, a shaft sleeve 102, a clearance adjusting nut 103, an encoder 104, a ball 106, and a control box 110; the conical shaft 101 is arranged inside the shaft sleeve 102. Both the conical shaft 101 and the shaft sleeve 102 are made of non-magnetic alloy copper and have self-lubricating properties. The shaft sleeve 102 is fixedly installed on the turntable support 2. The taper range of the conical shaft 101 and the shaft sleeve 102 is from 1:10 to 1:13. Preferably, the taper of the conical shaft 101 and the shaft sleeve 102 is 1:12. The clearance adjusting nut 103 is threadedly installed at the lower part of the shaft sleeve 102. There is a threaded cap screwed onto the shaft sleeve 102 to reinforce the clearance adjusting nut 103. A conical pit 111 is formed at the bottom of the conical shaft 101. The taper of the conical pit 111 at the bottom of the conical shaft 101 is from 1:0.7 to 1:0.9. Preferably, the taper of the conical pit 111 at the bottom of the conical shaft 101 is 1:0.866. The ball 106 is installed in the conical pit 111. A gasket 107 is installed at the middle position inside the clearance adjusting nut 103. The ball 106 is made of zirconia ceramic material, and the gasket 107 is made of agate material. The encoder 104 also includes a moving piece and a fixed piece of the encoder 104. The moving piece of the encoder 104 is fixed on the shoulder at the lower end of the conical surface of the conical shaft 101. The encoder 104 is a non-magnetic time grating encoder. The fixed piece of the encoder 104 is installed in the bottom hole of the shaft sleeve 102. A positioning nut 108 is installed between the moving piece of the encoder 104 and the conical shaft 101. The lead-out ends of the moving piece and the fixed piece of the encoder 104 both pass through the holes at the bottom end of the clearance adjusting nut 103 and are electrically connected to the control box 110 through a cable 109. The control box 110 realizes power supply and data display.

[0040] The clearance between the conical shaft 101 and the shaft sleeve 102 is adjusted by using the clearance adjusting nut 103 to be slightly damped for free rotation. After adjustment, the clearance between the moving piece and the fixed piece of the encoder 104 is between 0.35 and 0.45 mm, and the relative position meets the requirements of the best performance index of the encoder. The threaded cap is used to fix the clearance adjusting nut 103 to prevent the clearance adjusting nut 103 from sliding. The positioning nut 108 can prevent the moving piece of the encoder 104 from being damaged by misoperation during transportation and installation. The distance between the control box 110 and the encoder 104 should be greater than 2 meters to avoid affecting the geomagnetic measurement.

[0041] Further, the locking assembly includes a base 401, an outer shaft sleeve 402, a socket pin 403, a ball head screw 404, a connecting sleeve 405, a handle rod 406, a stop block 407, and a locking handle 408. The outer shaft sleeve 402 is installed on the outer shoulder of the shaft sleeve 102, and there is a clearance fit between the outer shaft sleeve 402 and the shaft sleeve 102. A crescent groove is provided on the inner side of the outer shaft sleeve 402, and the socket pin 403 is arranged in the crescent groove. One end of the ball head screw 404 is threadedly installed through the outer shaft sleeve 402 in a threaded manner and extends into the crescent groove. One end of the ball head screw 404 is threaded, and the other end is spherical. A cylindrical pin is assembled at the spherical end of the ball head screw 404. The stop block 407 is installed through the base 401, and the base 401 is fixed on the turntable surface 5. The handle rod 406 is installed in the hole of the stop block 407. One end of the handle rod 406 is a stepped cylinder, and the other end is spherical. A cylindrical pin is installed at the spherical end of the handle rod 406. The locking handle 408 is fixed on the side of the handle rod 406 away from the ball head screw 404. The connecting sleeve 405 is a thin-walled cylindrical structure, and orthogonal strip-shaped limiting grooves are respectively provided at both ends. Cylindrical pins are respectively press-fitted at the relative spherical ends of the ball head screw 404 and the handle rod 406 and respectively extend into the corresponding strip-shaped limiting grooves. By driving the ball head screw 404, the connecting sleeve 405, and the handle rod 406 through the locking handle 408, the outer shaft sleeve 402, the socket pin 403, and the shaft sleeve 102 are locked, thereby realizing the locking of the turntable. When the ball head screw 404 and the handle rod 406 are staggered by no more than 3 degrees, unlocking and locking can be achieved.

[0042] Further, the fine adjustment assembly includes a center seat 409, a center body 410, a thimble body 412, a thimble seat 413, a thimble rod 414, and a fine adjustment handle 415. Both the center seat 409 and the thimble seat 413 are fixed on the base 401. One end of the center body 410 extends into the center seat 409, and a non-magnetic spring 411 is provided inside the center seat 409. The non-magnetic spring 411 is fixed between the center seat 409 and the center body 410. The thimble rod 414 is threadedly connected to the inside of the thimble seat 413. The fine adjustment handle 415 is installed at one end of the thimble rod 414. Convex platforms are respectively provided on the inner side of the fine adjustment handle 415 and the outer side of the thimble seat 413 to limit the moving distance of the fine adjustment handle 415. One end of the thimble body 412 extends into the thimble rod 414, and the relative ends of the center body 410 and the thimble body 412 are respectively pressed on both sides of the protruding part of the outer shaft sleeve 402. A relatively large gap is provided inside the center seat 409, enabling the center body 410 to have a small amount of swing when making a reciprocating movement inside the center seat 409 to adapt to the inclination of the center body 410 during fine adjustment, thereby limiting the fine adjustment range of the turntable to less than 1 degree and ensuring that the relative inclination of the center body 410 and the thimble body 412 caused by fine adjustment is within the limited range.

[0043] Further, the support adjusting mechanism includes a support nut 302 and a support adjusting screw 301; the support nut 302 is installed on the turntable support 2, the support adjusting screw 301 is threadedly installed on the support nut 302, the support adjusting screw 301 is supported on the support block 303, and the number of the support adjusting screws 301 and the support nuts 302 is three each, and they are evenly distributed on the turntable support 2. The bottom of each support block 303 and the inside of the support adjusting screw 301 both adopt a hemispherical structure, making the adjustment more convenient and more stable during long-term operation.

[0044] Further, the leveling adjusting mechanism includes a detection level 602, a calibration level 605 and two level adjusting components; the level adjusting component includes a level fixing block 601 and a screw seat 604; the level fixing block 601 and the screw seat 604 are both fixed on the turntable surface 5; the detection direction of the detection level 602 is perpendicular to the detection direction of the calibration level 605, and the distances of the detection level 602 and the calibration level 605 from the center position of the turntable surface 5 are equal; one side of the detection level 602 and the calibration level 605 are respectively installed on the corresponding level fixing blocks 601, and the other sides are respectively installed on the corresponding level adjusting screws 603, and each level adjusting screw 603 is respectively threadedly installed on the corresponding screw seat 604. By the level adjusting component, the lifting of the detection level 602 and the calibration level 605 can be realized, and the lifted detection level 602 and calibration level 605 are locked by screws, so that the verticality of the rotating shaft of the component coil can be detected.

[0045] The present invention also provides an adjustment method for a digital non-magnetic turntable for geomagnetic vector observation, including the following steps:

[0046] Step 1, when installing the turntable, set the support adjusting mechanism on the observation pier and place it in the middle of the observation pier, then place the turntable on the support adjusting mechanism, and then install the used or calibrated component coil on the turntable surface 5;

[0047] Step 1.1, place the connecting line direction of the two support adjusting screws 301 of the support adjusting mechanism in the magnetic north-south or magnetic east-west direction, and align the center of the turntable with the center of the observation pier;

[0048] Step 1.2, bond the support block 303 of the support adjusting mechanism to the pier surface of the observation pier.

[0049] Step 2, when adjusting the turntable, adjust the leveling adjusting mechanism and detect the verticality of the rotating shaft of the component coil placed on the turntable surface 5, so that the rotating shaft of the component coil placed on the turntable surface 5 is in a vertical state. At this time, both the detection level and the calibration level of the leveling adjusting mechanism are in the centered state;

[0050] Step 2.1: Rotate the inspection level 602 of the level adjustment mechanism to the direction of the connection line of the two support adjustment screws 301 of the support adjustment mechanism, and rotate the support adjustment screws 301 of the support adjustment mechanism to adjust the bubble of the inspection level 602 to the middle position.

[0051] Step 2.2: Rotate the turntable tabletop 5 by 180°. Adjust half of the bubble deviation with the level adjustment screw 603 on one side of the inspection level 602 of the level adjustment mechanism, and adjust the other half with the support adjustment screw 301 of the support adjustment mechanism.

[0052] Step 2.3: Repeat Steps 2.1 and 2.2 until the difference in the bubble reading on the inspection level 602 of the level adjustment mechanism in this direction does not exceed 0.2 grids, that is, the turning difference of the bubble does not exceed 4 mm / m.

[0053] Step 2.4: Rotate the turntable tabletop 5 by 120°, and repeat the above Steps 2.1 and 2.2 until the bubble of the inspection level 602 of the level adjustment mechanism is in the middle position when the turntable tabletop 5 rotates to any angle.

[0054] Step 2.5: Adjust the level adjustment screw 603 of the calibration level 605 of the level adjustment mechanism to adjust the bubble to the middle. Arbitrarily rotate the turntable tabletop 5, and the bubble of the calibration level 605 of the level adjustment mechanism is in the middle. Otherwise, go back to Step 2.1 for readjustment.

[0055] Step 2.6: Rotate the turntable tabletop 5 so that the component coil on the turntable tabletop 5 rotates to the normal working azimuth angle.

[0056] Step 3: Orient with a compass, set the axis of the vertically placed component coil in the magnetic north-south or magnetic east-west direction, finely adjust the orientation angle through the rotating shaft adjustment mechanism 4, and make the absolute value of the measured component the minimum. At this time, the orientation of the component coil is the magnetic north-south or magnetic east-west direction.

[0057] Step 4: When measuring the turning error of the component coil, first measure the current orientation angle as the first component value, rotate the turntable by 180°, and then measure the current orientation angle as the second component value. Then the difference between the first component value and the second component value is the turning error of the component coil.

[0058] Step 4.1: At the current observation azimuth angle, measure 5 groups of component data respectively through the component coil device, eliminate the maximum and minimum values among them, and calculate the average value of the remaining 3 groups of data.

[0059] Step 4.2: Rotate the turntable tabletop 5 by 180°, measure 5 groups of component data respectively through the component coil device, eliminate the maximum and minimum values among them, and calculate the average value of the remaining 3 groups of data.

[0060] Step 4.3: Calculate the difference between the two averages in Step 4.1 and Step 4.2, which is the steering error of the component coil, where the component measurement error is introduced due to the non-coincidence of the axis of the half component coil shaft and the rotation axis.

[0061] As described above, although the present invention has been shown and described with reference to specific preferred embodiments, it should not be construed as a limitation on the present invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A digital non-magnetic turntable for geomagnetic field vector observation, characterized in that: It includes a conical rotating shaft mechanism, a turntable support (2), a support adjusting mechanism, a rotating shaft adjusting mechanism (4), a turntable surface (5), and a level adjusting mechanism; The conical rotating shaft mechanism is fixedly installed on the turntable support (2), and the turntable support (2) fixes the conical rotating shaft mechanism; the support adjusting mechanism is installed on the turntable support (2), and the support adjusting mechanism adjusts the levelness of the turntable support (2); the turntable surface (5) is installed on the conical rotating shaft mechanism, and the level adjusting mechanism is installed on the turntable surface (5), and the level adjusting mechanism detects the verticality of the rotating shaft of the component coil placed on the turntable surface (5); the rotating shaft adjusting mechanism (4) is fixed on the turntable surface (5), and the rotating shaft adjusting mechanism (4) further includes a locking assembly and a fine-tuning assembly. The conical rotating shaft mechanism and the rotating shaft adjusting mechanism (4) are relatively locked by the locking assembly, and the rotation angle between the conical rotating shaft mechanism and the turntable surface (5) is finely adjusted by the fine-tuning assembly.

2. The digital non-magnetic turntable for geomagnetic field vector observation according to claim 1, wherein: The conical rotating shaft mechanism includes a taper shaft (101), a shaft sleeve (102), a clearance adjusting nut (103), an encoder (104), a ball (106), and a control box (110); the taper shaft (101) is arranged inside the shaft sleeve (102), the shaft sleeve (102) is fixedly installed on the turntable support (2), and the clearance adjusting nut (103) is threadedly installed at the lower part of the shaft sleeve (102); the ball (106) is arranged at the bottom of the taper shaft (101); the encoder (104) is arranged between the taper shaft (101) and the shaft sleeve (102), and the encoder (104) is electrically connected to the control box (110) through a cable (109), and the control box (110) realizes power supply and data display.

3. The digital non-magnetic turntable for geomagnetic field vector observation according to claim 2, wherein: The locking assembly includes a base (401), an outer shaft sleeve (402), a sleeve pin (403), a ball head screw (404), a connecting sleeve (405), a handle rod (406), a stop block (407), and a locking handle (408); the outer shaft sleeve (402) is installed on the outer shoulder of the shaft sleeve (102), a crescent groove is opened on the inner side of the outer shaft sleeve (402), and the sleeve pin (403) is arranged in the crescent groove; one end of the ball head screw (404) is threadedly installed through the outer shaft sleeve (402) and extends into the crescent groove; the stop block (407) is installed through the base (401), and the base (401) is fixed on the turntable surface (5); the handle rod (406) is installed in the hole of the stop block (407), and the locking handle (408) is fixed on the side of the handle rod (406) away from the ball head screw (404); orthogonal strip-shaped limiting grooves are respectively opened at both ends of the connecting sleeve (405); cylindrical pins are respectively press-fitted on the relative spherical surfaces of the handle rod (406) and the ball head screw (404) and respectively extend into the corresponding strip-shaped limiting grooves.

4. The digital non-magnetic turntable for geomagnetic field vector observation according to claim 3, characterized in that: The fine-tuning component includes a center seat (409), a center body (410), a thimble body (412), a thimble seat (413), a thimble rod (414), and a fine-tuning handle (415); both the center seat (409) and the thimble seat (413) are fixed on the base (401), one end of the center body (410) extends into the center seat (409), a non-magnetic spring (411) is arranged inside the center seat (409), and the non-magnetic spring (411) is fixed between the center seat (409) and the center body (410); the thimble rod (414) is threadedly connected to the inside of the thimble seat (413), the fine-tuning handle (415) is installed at one end of the thimble rod (414), one end of the thimble body (412) extends into the thimble rod (414), and the opposite ends of the center body (410) and the thimble body (412) are respectively pressed against both sides of the protruding part of the shaft outer sleeve (402).

5. The digital non-magnetic turntable for geomagnetic field vector observation according to claim 1, characterized in that: The support adjusting mechanism includes a support nut (302) and a support adjusting screw (301); the support nut (302) is installed on the turntable support (2), the support adjusting screw (301) is threadedly installed on the support nut (302), and the support adjusting screw (301) is supported on the support block (303).

6. The digital non-magnetic turntable for geomagnetic field vector observation according to claim 1, characterized in that: The level adjusting mechanism includes a detection level (602), a calibration level (605), and two level adjusting components; the level adjusting component includes a level fixing block (601) and a screw seat (604); both the level fixing block (601) and the screw seat (604) are fixed on the turntable surface (5); the detection direction of the detection level (602) is perpendicular to the detection direction of the calibration level (605); one side of the detection level (602) and the calibration level (605) is respectively installed on the corresponding level fixing block (601), and the other side is respectively installed on the corresponding level adjusting screw (603), and each level adjusting screw (603) is respectively threadedly installed on the corresponding screw seat (604).

7. A method for adjusting a digital non-magnetic turntable for geomagnetic field vector observation according to any one of claims 1-6, characterized in that, It includes the following steps: Step 1, when installing the turntable, set the support adjusting mechanism on the observation pier and place it in the middle of the observation pier, then place the turntable on the support adjusting mechanism, and then install the used or calibrated component coil on the turntable surface (5). Step 2, when adjusting the turntable, adjust the level adjusting mechanism and detect the verticality of the axis of rotation of the component coil placed on the turntable surface (5), so that the axis of rotation of the component coil placed on the turntable surface (5) is in a vertical state. At this time, both the detection level and the calibration level of the level adjusting mechanism are in the centered state. Step 3, with compass orientation, set the axis of the vertically placed component coil in the magnetic north-south or magnetic east-west direction, finely adjust the orientation angle through the rotating shaft adjusting mechanism (4), and make the absolute value of the measured component the minimum. At this time, the orientation of the component coil is the magnetic north-south or magnetic east-west direction. Step 4, when measuring the turning error of the component coil, first test that the current orientation angle is the first component value, rotate the turntable by 180°, and then test that the current orientation angle is the second component value. Then the difference between the first component value and the second component value is the turning error of the component coil.

8. The adjustment method of the digital non-magnetic turntable for geomagnetic field vector observation according to claim 7, characterized in that In Step 1, the specific steps for installing the turntable are as follows: Step 1.1, place the connecting line direction of the two support adjusting screws (301) of the support adjusting mechanism in the magnetic north-south or magnetic east-west direction, and align the center of the turntable with the center of the observation pier; Step 1.2, firmly bond the support block (303) of the support adjusting mechanism to the pier surface of the observation pier.

9. The adjustment method of the digital non-magnetic turntable for geomagnetic field vector observation according to claim 7, characterized in that In Step 2, the specific steps for leveling the turntable are as follows: Step 2.1, turn the inspection level (602) of the level adjusting mechanism to the connecting line direction of the two support adjusting screws (301) of the support adjusting mechanism, and rotate the support adjusting screws (301) of the support adjusting mechanism to adjust the bubble of the inspection level (602) to the middle position; Step 2.2, rotate the turntable tabletop (5) by 180°, and adjust half of the bubble deviation with the level adjusting screw (603) on one side of the inspection level (602) of the level adjusting mechanism, and adjust the other half with the support adjusting screw (301) of the support adjusting mechanism; Step 2.3, repeat Steps 2.1 and 2.2 until the difference in the bubble readings on the inspection level (602) of the level adjusting mechanism in this direction does not exceed 0.2 grids; Step 2.4, rotate the turntable tabletop (5) by 120°, and repeat the above Steps 2.1 and 2.2 until the bubble of the inspection level (602) of the level adjusting mechanism is in the middle position when the turntable tabletop (5) rotates to any angle; Step 2.5, adjust the level adjusting screw (603) of the calibration level (605) of the level adjusting mechanism to adjust the bubble to the middle. Arbitrarily rotate the turntable tabletop (5), and the bubble of the calibration level (605) of the level adjusting mechanism is in the middle. Otherwise, go back to Step 2.1 to readjust; Step 2.6, rotate the turntable tabletop (5) so that the component coil on the turntable tabletop (5) rotates to the normal working azimuth angle.

10. The adjustment method of the digital non-magnetic turntable for geomagnetic field vector observation according to claim 7, characterized in that, In Step 4, the specific steps for measuring the steering error are as follows: Step 4.1, at the current observation azimuth angle, measure 5 groups of component data respectively through the component coil device, eliminate the maximum and minimum values, and calculate the average value of the remaining 3 groups of data; Step 4.2, rotate the turntable tabletop (5) by 180°, measure 5 groups of component data respectively through the component coil device, eliminate the maximum and minimum values, and calculate the average value of the remaining 3 groups of data; Step 4.3, calculate the difference between the two average values in Steps 4.1 and 4.2, which is the steering error of the component coil, and half of the component measurement error introduced by the non-coincidence of the axis of the component coil rotating shaft and the rotating shaft.

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