A limit protection device for inertial navigation calibration

Abstract

The present invention discloses a limit protection device for inertial navigation calibration, which includes a driving gear installed at the upper end of a main shaft. One side of the driving gear meshes with a driven gear installed on a gear shaft. The bottom of the gear shaft is fixed on a support plate, and a thrust plate is installed at the top of the gear shaft. A first optical disk is installed on the driven gear, and a second optical disk is installed on the first optical disk through a transition seat. On the support plate, a third groove-shaped optical sensor and a fourth groove-shaped optical sensor are respectively installed through two first optical supports. On the support plate, a bracket is installed through a support rod, and a first groove-shaped optical sensor and a second groove-shaped optical sensor are respectively installed on the bracket through two second optical supports. A single-turn absolute angle encoder is installed on the main shaft. The present invention has both optical and mechanical limit protection functions, and realizes the expansion of the 360° measurement range of the single-turn absolute angle encoder to more than ±360° without the rotation zero-finding method.

Description

Technical Field

[0001] The present invention relates to a limit protection device for inertial navigation calibration. Background Art

[0002] In the position calibration test of inertial navigation devices, the calibration test angle range of many inertial navigation devices only needs to exceed ±360° to meet the actual position calibration requirements. When the rotation angle range exceeds ±360°, the turntable equipment for calibration test usually needs to be equipped with a rotary conductive slip ring to avoid the problem of transmission cable breakage during rotation. However, the conductive slip ring belongs to a wear and consumable part, and has problems of high production cost, unstable transmission performance, and short service life.

[0003] In addition, the commonly used single-turn absolute angle encoder can only be used for measurements within a rotation range of 360 degrees, and cannot determine the number of turns of the rotating spindle when the turntable is powered on, that is, whether it is in the range of -360° to 0° or 0° to 360°. Therefore, a multi-turn absolute angle encoder is required, and the price of the multi-turn absolute angle encoder is much higher than that of the single-turn absolute angle encoder.

[0004] Therefore, it is necessary to develop a limit protection device with a simple structure, low cost, safety and reliability, which can be applied to the turntable equipment for inertial navigation calibration with a ±360° rotation without slip ring design and a single-turn absolute angle encoder design. Summary of the Invention

[0005] The object of the present invention is to provide a limit protection device for inertial navigation calibration to solve the problems in the above background art.

[0006] The technical solution adopted to achieve the above object is that a limit protection device for inertial navigation calibration includes a driving gear installed at the upper end of the main shaft. One side of the driving gear is engaged with a driven gear installed on a gear shaft. The bottom of the gear shaft is fixed on a support plate, and a thrust plate is installed at the top of the gear shaft. A first optical disc is installed on the driven gear, and a second optical disc is installed on the first optical disc through a transition seat. The support plate is respectively installed with a third groove-shaped optical sensor and a fourth groove-shaped optical sensor through two first optical supports. A bracket is installed on the support plate through a support rod, and a first groove-shaped optical sensor and a second groove-shaped optical sensor are respectively installed on the bracket through two second optical supports. A single-turn absolute angle encoder is installed on the main shaft.

[0007] Furthermore, the lower end surface of the gear shaft is fixedly connected with the support plate, the upper end surface of the gear shaft is fixedly connected with the thrust plate, and a flange stop is machined at the middle position of the gear shaft. The driven gear is respectively in clearance fit with the lower end surface of the thrust plate and the upper end surface of the flange stop; the central hole of the driven gear is in clearance fit with the gear shaft, forming a rotating pair to realize the rotation of the driven gear around the gear shaft.

[0008] Furthermore, a sector-shaped groove at a specific angle is provided at the center position of the driven gear, and a sector-shaped protrusion placed in the sector-shaped groove is provided on the gear shaft. The included angle between the sector-shaped groove and the sector-shaped protrusion is symmetrically 125°. The sector-shaped protrusion moves within the sector-shaped groove, enabling the driven gear to rotate relative to the gear shaft within an angular range of -125° to +125°. The driving gear can only rotate within an angular range of -375° to +375°, realizing the mechanical limit protection function of the main shaft within an angular range of -375° to +375°.

[0009] Furthermore, the first optical disk is fixedly connected to the driven gear, the transition seat is fixedly connected to the first optical disk, and the second optical disk is fixedly connected to the transition seat, realizing the synchronous rotational movement of the first optical disk, the second optical disk, and the driven gear around the gear shaft.

[0010] Furthermore, the first groove-shaped optical sensor and the second groove-shaped optical sensor form three different on-off states. The main shaft determines the angular position range it is in through the three combined on-off states of the first groove-shaped optical sensor and the second groove-shaped optical sensor, and then feeds back the accurate angular position information of the main shaft through the single-turn absolute angle encoder.

[0011] Furthermore, the tooth number ratio of the driven gear to the driving gear is 3:1.

[0012] Furthermore, a first sector-shaped structure at a specific angle is provided on the outer edge of the first optical disk. The first sector-shaped structure is at the same level as the third groove-shaped optical sensor and the fourth groove-shaped optical sensor and is arranged at a specific angle. The first sector-shaped structure rotates forward and backward into the third groove-shaped optical sensor and the fourth groove-shaped optical sensor, triggering a change in the on-off state of the third groove-shaped optical sensor and the fourth groove-shaped optical sensor by blocking the on-off of the light path. The included angle between the first sector-shaped structure and the third groove-shaped optical sensor is 122°, and the included angle between the first sector-shaped structure and the fourth groove-shaped optical sensor is 122°.

[0013] Furthermore, a second sector-shaped structure is provided on the outer edge of the second optical disk. The second sector-shaped structure is at the same level as the first groove-shaped optical sensor and the second groove-shaped optical sensor and is arranged at a specific angle. The second sector-shaped structure rotates into the first groove-shaped optical sensor and the second groove-shaped optical sensor, triggering a change in the on-off state of the first groove-shaped optical sensor and the second groove-shaped optical sensor by blocking the on-off of the light path. The included angle between the second sector-shaped structure and the first groove-shaped optical sensor is 59°, and the included angle between the second sector-shaped structure and the second groove-shaped optical sensor is 59°.

[0014] Beneficial effects

[0015] Compared with the prior art, the present invention has the following advantages.

[0016] 1. The present invention can achieve the functions of photoelectric limit and mechanical limit protection for the spindle of the turntable used for inertial navigation calibration on a set of structures, solve the problem of cable winding and breaking in the ±360° non-slip ring design, and improve the reliability and safety of the equipment.

[0017] 2. The present invention can expand the measurement range of a single-turn absolute angle encoder from 360° to more than ±360° without the need for rotational zeroing. The structure is simple, easy to implement, and has a low manufacturing cost, and is particularly suitable for miniaturized inertial navigation calibration turntable equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described in detail below with reference to the accompanying drawings.

[0019] Figure 1 is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 is a sectional view of the structure of the present invention;

[0021] Figure 3 is a schematic diagram of the installation position of the first optical disk in the present invention;

[0022] Figure 4 is a schematic diagram of the installation positions of the gear shaft and the driven gear in the present invention;

[0023] Figure 5 is a three-dimensional structure diagram of the driven gear in the present invention;

[0024] Figure 6 is a three-dimensional structure diagram of the gear shaft in the present invention;

[0025] Figure 7 is a three-dimensional structure diagram of the first optical disk in the present invention;

[0026] Figure 8 is a three-dimensional structure diagram of the second optical disk in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The present invention will be further described below in conjunction with embodiments and the accompanying drawings.

[0028] As Figures 1 - 8As shown in the figure, a limit protection device for inertial navigation calibration includes a driving gear 13 installed at the upper end of a main shaft 10. One side of the driving gear 13 meshes with a driven gear 5 installed on a gear shaft 16. The bottom of the gear shaft 16 is fixed on a support plate 8, and a thrust plate 2 is installed at the top of the gear shaft 16. A first optical disk 3 is installed on the driven gear 5, and a second optical disk 1 is installed on the first optical disk 3 through an adapter seat 4. On the support plate 8, a third groove-shaped optical sensor 151 and a fourth groove-shaped optical sensor 152 are respectively installed through two first optical supports 14. On the support plate 8, a bracket 12 is installed through a support rod 9. On the bracket 12, a first groove-shaped optical sensor 61 and a second groove-shaped optical sensor 62 are respectively installed through two second optical supports 7. A single-turn absolute angle encoder 11 is installed on the main shaft 10.

[0029] The lower end face of the gear shaft 16 is fixedly connected to the support plate 8, the upper end face of the gear shaft 16 is fixedly connected to the thrust plate 2, and a flange stop 161 is machined at the middle position of the gear shaft 16. The driven gear 5 is in clearance fit with the lower end face of the thrust plate 2 and the upper end face of the flange stop 161 respectively; the central hole 51 of the driven gear 5 is in clearance fit with the gear shaft 16, forming a rotating pair to realize the rotational movement of the driven gear 5 around the gear shaft 16.

[0030] A sector groove 52 with a specific angle is provided at the central position of the driven gear 5, and a sector protrusion 162 is provided on the gear shaft 16 and placed in the sector groove 52. The included angle between the sector groove 52 and the sector protrusion 162 is symmetrically 125°. The sector protrusion 162 moves in the sector groove 52, enabling the driven gear 5 to rotate relative to the gear shaft 16 within an angular range of -125° to +125°, and the driving gear 13 to rotate within an angular range of -375° to +375°, realizing the mechanical limit protection function of the main shaft 10 within an angular range of -375° to +375°.

[0031] The first optical disk 3 is fixedly connected to the driven gear 5, the adapter seat 4 is fixedly connected to the first optical disk 3, and the second optical disk 1 is fixedly connected to the adapter seat 4, realizing the synchronous rotational movement of the first optical disk 3, the second optical disk 1, and the driven gear 5 around the gear shaft 16.

[0032] The first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62 form three different on-off states. The main shaft 10 determines the angular position range it is in through the three combined on-off states of the first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62, and then feeds back the accurate angular position information of the main shaft 10 through the single-turn absolute angle encoder 11.

[0033] The tooth number ratio of the driven gear 5 to the driving gear 13 is 3:1.

[0034] A first sector structure 31 at a specific angle is provided on the outer edge of the first optical disk 3. The first sector structure 31 is at the same level as the third grooved optical sensor 151 and the fourth grooved optical sensor 152 and is arranged at a specific angle. The first sector structure 31 rotates forward and backward into the third grooved optical sensor 151 and the fourth grooved optical sensor 152, and triggers and changes the on-off states of the third grooved optical sensor 151 and the fourth grooved optical sensor 152 by blocking the on-off of the optical path. The included angle between the first sector structure 31 and the third grooved optical sensor 151 is 122°, and the included angle between the first sector structure 31 and the fourth grooved optical sensor 152 is 122°.

[0035] A second sector structure 111 is provided on the outer edge of the second optical disk 1. The second sector structure 111 is at the same level as the first grooved optical sensor 61 and the second grooved optical sensor 62 and is arranged at a specific angle. The second sector structure 111 rotates into the first grooved optical sensor 61 and the second grooved optical sensor 62, and triggers and changes the on-off states of the first grooved optical sensor 61 and the second grooved optical sensor 62 by blocking the on-off of the optical path. The included angle between the second sector structure 111 and the first grooved optical sensor 61 is 59°, and the included angle between the second sector structure 111 and the second grooved optical sensor 62 is 59°.

[0036] In the present invention, a gear shaft 16 is installed at the upper end of the support plate 8, a thrust plate 2 is fixed at the upper end of the gear shaft 16, a driven gear 5 is installed at the middle position of the gear shaft 16, the first optical disk 3 is installed on the driven gear 5, a transition seat 4 is installed on the first optical disk 3, the second optical disk 1 is installed on the transition seat 4, two first optical supports 14 are also installed on the support plate 8, the third grooved optical sensor 151 and the fourth grooved optical sensor 152 are respectively installed on the two first optical supports 14, four support rods 9 are also installed on the support plate 8, a bracket 12 is fixed at the upper ends of the four support rods 9, two second optical supports 7 are installed on the bracket 12, the first grooved optical sensor 61 and the second grooved optical sensor 62 are respectively installed on the two second optical supports 7, the driven gear 5 meshes with the driving gear 13, the driving gear 13 is fixedly installed at the upper end of the main shaft 10, and a single-turn absolute angle encoder 11 is also installed on the main shaft 10.

[0037] The lower end face of the gear shaft 16 is fixedly connected to the support plate 8 by screws, and the upper end face of the gear shaft 16 is fixedly connected to the thrust plate 8 by screws. A flange stop 161 is machined at the middle position of the gear shaft 16. The driven gear 5 is in clearance fit with the lower end face of the thrust plate 2 and the upper end face of the flange stop 161 on the gear shaft 16 respectively. The driven gear 5 is in clearance fit with the gear shaft 16 through the central hole 51 at the central position of the driven gear 5, forming a rotating pair to realize the rotation of the driven gear 5 around the gear shaft 16; A sector groove 52 with a specific angle is also provided at the central position of the driven gear 5, and a sector convex block 162 with a specific angle is provided at the middle position of the gear shaft 16.

[0038] The included angle between the sector groove 52 on the driven gear 5 and the sector convex block 162 on the gear shaft 16 is symmetrically 125°, so that the driven gear 5 can only rotate relative to the gear shaft 16 within the angle range of -125° to +125°, and the driving gear 13 can only rotate within the angle range of -375° to +375°, realizing the mechanical limit protection function of the main shaft 10 within the angle range of -375° to +375°.

[0039] The first optical disk 3 is fixedly connected to the driven gear 5 by screws, the transition seat 4 is fixedly connected to the first optical disk 3 by screws, and the second optical disk 7 is fixedly connected to the transition seat 4 by screws, realizing the synchronous rotation of the first optical disk 3, the second optical disk 1, and the driven gear 5 around the gear shaft 16.

[0040] A first sector structure 31 with a specific angle is provided at the outer edge position of the first optical disk 3. The first sector structure 31 is at the same level as the third groove-type optical sensor 151 and the fourth groove-type optical sensor 152 and is arranged at a specific angle. It can rotate forward and backward into the third groove-type optical sensor 151 and the fourth groove-type optical sensor 152, and trigger and change the on-off states of the third groove-type optical sensor 151 and the fourth groove-type optical sensor 152 by blocking the on-off of the light path.

[0041] The main shaft 10 judges whether it rotates to the upper and lower angle limits by triggering the on-off states of the third groove-type optical sensor 151 and the fourth groove-type optical sensor 152. When the third groove-type optical sensor 151 changes from the normally off state to the normally on state, it is judged that the main shaft 10 rotates to the upper limit angle position; when the fourth groove-type optical sensor 152 changes from the normally off state to the normally on state, it is judged that the main shaft 10 rotates to the lower limit angle position.

[0042] The included angle between the first sector structure 31 of the first optical disk 3 and the third groove-shaped optical sensor 151 is 122°, and the included angle with the fourth groove-shaped optical sensor 152 is 122°. When the driving gear 13 rotates to the -366° angular position, the third groove-shaped optical sensor 151 is triggered, and when the driving gear 13 rotates to the +366° angular position, the fourth groove-shaped optical sensor 152 is triggered, realizing the optical limit protection function of the main shaft 10 within the rotation angle range of -366° to +366°.

[0043] A second sector structure 111 is provided at the outer edge position of the second optical disk 1. The second sector structure 111 is at the same level as the first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62 and is arranged at a specific angle. It can rotate and move into the first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62, triggering and changing the on-off states of the first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62 by blocking the on-off of the optical path. The included angle between the second sector structure 111 of the second optical disk 1 and the first groove-shaped optical sensor 61 is 59°, and the included angle with the second groove-shaped optical sensor 62 is 59°.

[0044] The first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62 form three different on-off states. The main shaft 10 can judge the angular position range it is in through the three combined on-off states of the first groove-shaped optical sensor 61 and the second groove-shaped optical sensor 62: when it is in the state of "the first groove-shaped optical sensor 61 is always on and the second groove-shaped optical sensor 62 is always on", it can be judged that the main shaft is in the angular position range of -177° to +177°; when it is in the state of "the first groove-shaped optical sensor 61 is always off and the second groove-shaped optical sensor 62 is always on", it can be judged that the main shaft is in the angular position range of -366° to -177°; when it is in the state of "the first groove-shaped optical sensor 61 is always on and the second groove-shaped optical sensor 62 is always off", it can be judged that the main shaft is in the angular position range of +177° to +366°. Furthermore, the accurate angular position information of the main shaft 10 is fed back through the single-turn absolute angle encoder 11.

[0045] The main shaft 10 feeds back the angular position information through the single-turn absolute angle encoder 11.

[0046] The working principle of the present invention is that when the turntable for calibration is powered on, the upper computer software on the turntable can determine the angular position range where the main shaft 10 is located according to the three combined on-off states of the first grooved photoelectric sensor 61 and the second grooved photoelectric sensor 62. Since the three angular range measuring ranges of -366° to -177°, -177° to +177°, and +177° to +366° are all less than 360°, which meets the principle of absolute coding uniqueness of the single-turn absolute angle encoder 11, the upper computer software on the turntable can determine the accurate angular position of the main shaft within the range of -366° to +366° according to the angular information fed back by the single-turn absolute angle encoder 11, thereby expanding the applicable range of the angular measurement of the single-turn absolute angle encoder 11 from within 360° to -366° to +366°; when the main shaft 10 rotates, the driving gear 13 fixedly connected to the main shaft drives the driven gear 5 to rotate at a reduced speed. When the main shaft 10 rotates to the angular position of -366°, the first optical disk 3 rotates to the angular position of -122°, and the third grooved photoelectric sensor 151 changes from the normally off state to the normally on state, triggering the electrical limit protection at the lower limit angular position of -366°. When the main shaft 10 rotates to the angular position of +366°, the first optical disk 3 rotates to the angular position of +122°, and the fourth grooved photoelectric sensor 152 changes from the normally off state to the normally on state, triggering the electrical limit protection at the upper limit angular position of +366°; since the driven gear 5 can only rotate within the angular range of -125° to +125° relative to the gear shaft 16, the driving gear 13 meshing with the driven gear 5 can only rotate within the angular range of -375° to +375°, thereby realizing the mechanical limit protection function that the main shaft 10 can only rotate within the angular range of -375° to +375°.

[0047] The present invention provides a limit protection device for inertial navigation calibration. The device has photoelectric and mechanical limit protection functions, and can expand the 360° measurement range of the single-turn absolute angle encoder to more than ±360° without the need for rotational zeroing; it also has the characteristics of simple structure and low manufacturing cost, and is particularly suitable for miniaturized inertial navigation calibration turntable equipment.

Claims

1. A limit protection device for inertial navigation calibration, comprising a driving gear (13) installed at the upper end of a main shaft (10). Characterized in that, One side of the driving gear (13) is engaged with a driven gear (5) installed on a gear shaft (16). The bottom of the gear shaft (16) is fixed on a support plate (8). A thrust plate (2) is installed at the top of the gear shaft (16). A first optical disk (3) is installed on the driven gear (5). A second optical disk (1) is installed on the first optical disk (3) through a transition seat (4). The support plate (8) is respectively installed with a third groove-shaped optical sensor (151) and a fourth groove-shaped optical sensor (152) through two first optical supports (14). The support plate (8) is installed with a bracket (12) through a support rod (9). The bracket (12) is respectively installed with a first groove-shaped optical sensor (61) and a second groove-shaped optical sensor (62) through two second optical supports (7). A single-turn absolute angle encoder (11) is installed on the main shaft (10). The lower end face of the gear shaft (16) is fixedly connected to the support plate (8), and the upper end face of the gear shaft (16) is fixedly connected to the thrust plate (2). A flange stop (161) is machined at the middle position of the gear shaft (16). The driven gear (5) is in clearance fit with the lower end face of the thrust plate (2) and the upper end face of the flange stop (161) respectively. The central hole (51) of the driven gear (5) is in clearance fit with the gear shaft (16) to form a rotating pair, realizing the rotational movement of the driven gear (5) around the gear shaft (16). A fan-shaped groove (52) with a specific angle is provided at the central position of the driven gear (5). A fan-shaped convex block (162) is provided on the gear shaft (16) and placed in the fan-shaped groove (52). The included angle between the fan-shaped groove (52) and the fan-shaped convex block (162) is symmetrically 125°. The fan-shaped convex block (162) moves in the fan-shaped groove (52), enabling the driven gear (5) to rotate relative to the gear shaft (16) within an angular range of -125° to +125°, and the driving gear (13) to rotate within an angular range of -375° to +375°, realizing the mechanical limit protection function of the main shaft (10) within an angular range of -375° to +375°.

2. A limit protection device for inertial navigation calibration according to claim 1. Characterized in that, The first optical disk (3) is fixedly connected to the driven gear (5), the transition seat (4) is fixedly connected to the first optical disk (3), and the second optical disk (1) is fixedly connected to the transition seat (4), realizing the synchronous rotational movement of the first optical disk (3), the second optical disk (1), and the driven gear (5) around the gear shaft (16).

3. A limit protection device for inertial navigation calibration according to claim 1. Characterized in that, The first groove-shaped photoelectric sensor (61) and the second groove-shaped photoelectric sensor (62) form three different on-off states. The main shaft (10) determines the range of the angular position it is in through the three combined on-off states of the first groove-shaped photoelectric sensor (61) and the second groove-shaped photoelectric sensor (62), and then feeds back the accurate angular position information of the main shaft (10) through the single-turn absolute angle encoder (11).

4. An inertial navigation calibration limiting protection device according to claim 1, characterized in that, the tooth number ratio of the driven gear (5) to the driving gear (13) is 3:

1.

5. An inertial navigation calibration limiting protection device according to claim 1, characterized in that, a first sector structure (31) with a specific angle is provided on the outer edge of the first optical disk (3). The first sector structure (31) is at the same level as the third groove-shaped photoelectric sensor (151) and the fourth groove-shaped photoelectric sensor (152) and is arranged at a specific angle. The first sector structure (31) rotates forward and backward into the third groove-shaped photoelectric sensor (151) and the fourth groove-shaped photoelectric sensor (152), and triggers and changes the on-off states of the third groove-shaped photoelectric sensor (151) and the fourth groove-shaped photoelectric sensor (152) by blocking the on-off of the optical path; the included angle between the first sector structure (31) and the third groove-shaped photoelectric sensor (151) is 122°, and the included angle between the first sector structure (31) and the fourth groove-shaped photoelectric sensor (152) is 122°.

6. An inertial navigation calibration limiting protection device according to claim 1, characterized in that, a second sector structure (111) is provided on the outer edge of the second optical disk (1). The second sector structure (111) is at the same level as the first groove-shaped photoelectric sensor (61) and the second groove-shaped photoelectric sensor (62) and is arranged at a specific angle. The second sector structure (111) rotates into the first groove-shaped photoelectric sensor (61) and the second groove-shaped photoelectric sensor (62), and triggers and changes the on-off states of the first groove-shaped photoelectric sensor (61) and the second groove-shaped photoelectric sensor (62) by blocking the on-off of the optical path; the included angle between the second sector structure (111) and the first groove-shaped photoelectric sensor (61) is 59°, and the included angle between the second sector structure (111) and the second groove-shaped photoelectric sensor (62) is 59°.

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