Electromechanical position-limiting device with an ultra-360-degree rotation angle

Abstract

The application discloses a kind of electromechanical limit devices of super 360 degree rotation angle.The electromechanical limit device includes fixed disc, swing mechanism, moving disc, stop block mechanism, the swing mechanism includes cross arm, rotating shaft, the stop block mechanism includes stop block seat, steel ball, buffer rod, first detection target piece, the axis of rotating shaft is perpendicular to the axis of moving disc, and rotating shaft is connected with fixed disc by bearing seat, and second detection target piece is arranged at the both ends of cross arm.Fixed disc is equipped with fixed disc magnet in the position of contact with the both ends of cross arm.The fixed disc on the both ends of cross arm is respectively equipped with cross arm proximity sensor for detecting second detection target piece, and the both ends of cross arm are respectively equipped with stop block proximity sensor for detecting first detection target piece.The electromechanical limit of the application can be realized to the moving disc super 360 degree rotation angle.The device has small friction, simple and reliable structure, strong impact resistance, and is especially suitable for gravitational wave detection telescope and other fields which are very sensitive to the change of friction in the process of limiting action.

Description

Technical Field

[0001] This invention relates to the field of electromechanical technology, specifically to an electromechanical limiting device with a rotation angle exceeding 360 degrees. This electromechanical limiting device has low friction, simple and reliable structure, and strong impact resistance, making it particularly suitable for fields such as gravitational wave detection telescopes where changes in friction during the limiting process are highly sensitive. Background Technology

[0002] For continuous observation, the azimuth axis of ground-based astronomical telescopes needs to rotate more than 360 degrees. At both ends of the azimuth axis's rotation range, electrical or mechanical limiting devices are typically required. A common type of mechanical limiting device exceeding 360 degrees uses an arc-shaped guide rail on the base, with a slider that moves along it. Energy-absorbing structures and stops are located at both ends of the guide rail, and a lever is mounted on the azimuth axis to push the slider. This limiting device is reliable and has been used in the field of astronomical telescopes for many years. However, with the increasing size of astronomical telescopes, the guide rail and slider of this limiting device have also become larger, increasing not only weight but also the manufacturing difficulty of the arc-shaped guide rail. The drawbacks of this limiting device can no longer be ignored. Another type of mechanical limiting device exceeding 360 degrees uses a large gear on the azimuth axis and a small gear meshing with it. The small gear is connected to a lead screw with a nut. By restricting the movement of the nut, the rotation of the gear is limited, thus limiting the rotation of the azimuth axis. The disadvantage of this type of limiting device is that the meshing error of the gear pair is directly transmitted to the azimuth axis, making it difficult to achieve high control precision for the azimuth axis. One type of mechanical limiting device, exceeding 360 degrees, uses a small rotating shaft parallel to the azimuth axis. This small shaft has a flange with protrusions on its edge. A stop is placed on the azimuth axis, which abuts against the flange protrusions, pushing the small rotating shaft to rotate. The rotation of the azimuth axis is limited by restricting the rotation range of the small rotating shaft. The disadvantage of this type of limiting device is that the buffer distance of the energy-absorbing device is relatively small, making it unsuitable for applications with large rotational inertia of the azimuth axis. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention proposes an electromechanical limiting device with a rotation angle exceeding 360 degrees. This electromechanical limiting device has low friction, simple and reliable structure, and strong impact resistance. It is particularly suitable for fields such as astronomical telescopes where the change in friction during the limiting process is very sensitive, and is especially suitable for electromechanical limiting of heavy-duty, large-inertia turntables.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] An electromechanical limiting device with a rotation angle exceeding 360 degrees includes a fixed plate, a swing mechanism, a moving plate, and a stop mechanism. The swing mechanism includes a horizontal arm and a rotating shaft. The stop mechanism includes a stop seat, a steel ball, a buffer rod, and a first detection target. The moving plate can rotate relative to the fixed plate around its own axis. The horizontal arm can rotate around the rotating shaft, the axis of which is perpendicular to the axis of the moving plate, and the rotating shaft is connected to the fixed plate through a bearing seat. Second detection target elements are provided at both ends of the horizontal arm. The stop seat is connected to the moving plate and has a longitudinal hole with its axis running vertically. The steel ball can move axially within the longitudinal hole. The longitudinal hole has a diameter smaller than that of the steel ball. A steel ball spring is provided above the steel ball, and the force of the steel ball spring pushes the steel ball toward the hole. A transverse hole in the left-right direction is provided on the stop block seat, and the buffer rod can move left and right in the transverse hole. An energy-absorbing spring is provided between the stop block seat and the buffer rod. When the buffer rod moves left and right in the transverse hole, the energy-absorbing spring absorbs the kinetic energy of the moving plate transmitted by the buffer rod. A transverse arm proximity sensor for detecting the second detection target is provided on the fixed plate near both ends of the transverse arm, and a stop block proximity sensor for detecting the first detection target is provided at both ends of the transverse arm.

[0006] Furthermore, when the horizontal arm is horizontal, the bottom of the steel ball is lower than the upper surface of the horizontal arm. When the stop mechanism rotates with the moving plate to the horizontal arm area, the upper surface of the horizontal arm pushes the steel ball upward to the stop seat, and the steel ball spring is further compressed.

[0007] Furthermore, the first detection target is a stop magnet, the second detection target is a cross arm magnet, and both the cross arm proximity sensor and the stop proximity sensor are Hall sensors that are sensitive to magnets.

[0008] Furthermore, the fixed plate is equipped with a fixed plate magnet at the position where it contacts the left and right ends of the horizontal arm. Before the steel ball is fully pushed into the stop seat, the torque of the spring force of the steel ball on the horizontal arm pivot is greater than the torque of the magnetic force of the fixed plate magnet on the horizontal arm pivot.

[0009] Furthermore, the cross arm is made of steel or has magnetic material at both ends where it contacts the fixed plate.

[0010] Furthermore, when one end of the horizontal arm moves downward and approaches the fixed plate, the nearby fixed plate magnet attracts the end to the fixed plate, and the nearby horizontal arm proximity sensor obtains a proximity signal. When the other end of the horizontal arm moves upward and approaches the moving plate, the stop proximity sensor installed at that end enters a state that can detect the position of the stop mechanism.

[0011] Furthermore, the energy-absorbing spring is a compression spring, tension spring, disc spring, damper, or a combination thereof. The energy storage and dissipation of the energy-absorbing spring and the stroke of the buffer rod are determined according to the limit value of the kinetic energy of the moving disc.

[0012] Furthermore, when the fixed plate is fixed relative to the ground, the center of gravity of the horizontal arm is higher than the axis of the rotating shaft. In this state, the horizontal arm is in an indeterminate state when it is horizontal.

[0013] Furthermore, when the stop mechanism is in the middle position of the horizontal arm, the horizontal arm is horizontal. Since the horizontal arm is in a static indeterminate state, when the stop mechanism moves away from the middle position of the horizontal arm, the horizontal arm will swing. Due to the pressure of the steel ball, the horizontal arm will swing in the direction in which the stop mechanism moves away until one end of the horizontal arm contacts the fixed plate.

[0014] Furthermore, several sets of swinging mechanisms are arranged around the circumference of the fixed plate.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] Compared to the circular arc guide rail solution, the present invention has a lower structural weight and is easier to manufacture.

[0017] Compared to the lead screw solution, the present invention has lower friction.

[0018] Compared to the flange solution, the present invention has a stronger load-bearing capacity and a longer buffer distance.

[0019] Overall, the electromechanical limiting device of the present invention has low friction, simple and reliable structure, and strong impact resistance, making it particularly suitable for precision instruments such as large astronomical telescopes. Attached Figure Description

[0020] Figure 1 This is a side view of an embodiment of the electromechanical limit device.

[0021] Figure 2 This is a top view of an embodiment of the electromechanical limit device.

[0022] Figure 3 This is a schematic diagram of the stop mechanism in an embodiment.

[0023] Figure 4 The side view of the moving disk in the embodiment at its extreme position in the counterclockwise direction.

[0024] Figure 5 This is a top view of the moving disk in the extreme position in the counterclockwise direction, as in the embodiment.

[0025] The markings in the diagram are: 1. Fixed plate; 2. Cross arm; 3. Rotating shaft; 4. Bearing; 5. Bearing seat; 6. Fixed plate magnet; 7. Cross arm magnet; 8. Cross arm proximity sensor; 9. Stop magnet; 10. Stop proximity sensor; 11. Moving plate; 12. Stop seat; 13. Steel ball; 14. Steel ball spring; 15. Energy-absorbing spring; 16. Buffer rod. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings.

[0027] This embodiment provides a method such as Figure 1-2 The electromechanical limit device shown has a rotation angle of over 360 degrees. The electromechanical limit device includes a fixed plate 1, a horizontal arm 2, a rotating shaft 3, a bearing 4, a bearing seat 5, a fixed plate magnet 6, a horizontal arm magnet 7, a horizontal arm proximity sensor 8, a stop magnet 9, a stop proximity sensor 10, a moving plate 11, a stop seat 12, a steel ball 13, a steel ball spring 14, an energy-absorbing spring 15, and a buffer rod 16.

[0028] For ease of explanation, the orientation is defined as follows: the fixed plate 1 is at the bottom, and the moving plate 11 is at the top.

[0029] In this embodiment, the fixed disk 1 is cylindrical and its position is fixed. The movable disk 11 can rotate around its own axis, and the axis of the movable disk 11 is coaxial with the axis of the fixed disk 1. Under the action of this invention, the range of rotation angle of the movable disk 11 relative to the fixed disk 1 is limited to greater than 360 degrees and less than 720 degrees.

[0030] In this embodiment, the horizontal arm 2, the rotating shaft 3, the bearing 4, and the bearing seat 5 form a rocking mechanism. The rocking mechanism can rotate around the rotating shaft 3. The axis of the rotating shaft 3 is perpendicular to the axis of the moving plate 11. The rocking mechanism is connected to the fixed plate 1 through the bearing seat 5.

[0031] like Figure 3 As shown, in this embodiment, the stop block seat 12, steel ball 13, steel ball spring 14, energy-absorbing spring 15, and buffer rod 16 constitute a stop block mechanism, which is connected to the moving plate 11 through the stop block seat 12.

[0032] In this embodiment, there is a horizontal arm proximity sensor 8 near each end of the horizontal arm 2. The horizontal arm proximity sensor 8 is installed on the fixed plate 1 and detects the horizontal arm magnets 7 connected to both ends of the horizontal arm 2. There is a stop proximity sensor 10 at each end of the horizontal arm 2 and the stop proximity sensor 10 detects the stop magnets 9 connected to the stop mechanism.

[0033] The stop block 12 in this embodiment has a hole with its axis running vertically, allowing the steel ball 13 to move axially within the hole. The diameter of the hole is smaller than the diameter of the steel ball 13 to prevent the steel ball 13 from falling out of the hole. Above the steel ball 13 is a steel ball spring 14, which is a compression spring that pushes the steel ball towards the hole with its elastic force.

[0034] In this embodiment, when the horizontal arm 2 is horizontal, the bottom of the steel ball 13 is lower than the upper surface of the horizontal arm 2. Furthermore, when the horizontal arm 2 is horizontal, when the stop mechanism rotates to the horizontal arm region with the moving disc 11, the upper surface of the horizontal arm 2 pushes the steel ball 13 upwards to the stop seat 12, and the steel ball spring 14 is further compressed.

[0035] In this embodiment, the fixed plate 1 is equipped with fixed plate magnets 6 at the positions that contact the left and right ends of the horizontal arm 2. The material of the horizontal arm 2 in this embodiment is steel (or magnetic material can be provided at the positions where the horizontal arm contacts the fixed plate). When one end of the horizontal arm 2 moves downward and approaches the fixed plate 1, the following actions will occur: 1) The nearby fixed plate magnet 6 attracts the end to the fixed plate 1; 2) The nearby horizontal arm proximity sensor 8 obtains a signal that the horizontal arm 2 is approaching; 3) The other end of the horizontal arm 2 moves upward and approaches the moving plate 11, and the stop proximity sensor 10 installed at that end enters a state that can detect the position of the stop magnet 9.

[0036] In this embodiment, before the steel ball 13 is fully pushed into the stop seat 12, the torque of the spring force of the steel ball spring 14 on the horizontal arm pivot 3 is greater than the torque of the magnetic force of the fixed plate magnet 6 on the horizontal arm pivot 3. This avoids direct contact between the stop seat 12 and the horizontal arm 2, reducing the frictional force generated to push the horizontal arm 2 to rotate.

[0037] The stop block seat 12 in this embodiment has a hole in the left-right direction, within which the buffer rod 16 can move left and right. An energy-absorbing spring 15 is located between the stop block seat 12 and the buffer rod 16. When the buffer rod 16 moves left and right within the hole of the stop block seat 12, the energy-absorbing spring 15 absorbs the kinetic energy of the moving plate 11 transmitted by the buffer rod 16. The energy-absorbing spring 15 can be a compression spring, a tension spring, a disc spring, a damper, or a combination thereof. The energy storage and dissipation of the energy-absorbing spring, and the stroke of the buffer rod, are determined based on the limit value of the kinetic energy of the moving plate. In this embodiment, the energy-absorbing spring 15 is a compression spring.

[0038] In this embodiment, the fixed plate 1 is fixed relative to the ground, and the center of gravity of the horizontal arm 2 is higher than the axis of the rotating shaft 3. In this state, the horizontal arm 2 is in a statically unstable state when it is horizontal. In particular, when the stop mechanism is located in the middle position of the horizontal arm 2, the horizontal arm 2 can be in a horizontal state. Since the horizontal arm 2 is a statically unstable structure, when the stop mechanism moves away from the middle position of the horizontal arm 2 as the moving plate rotates, the horizontal arm 2 will swing around the rotating shaft 3. Due to the pressure applied by the steel ball 13, the horizontal arm 2 will swing in the direction in which the stop mechanism moves away until one end of the horizontal arm 2 contacts the fixed plate 1.

[0039] Figure 4-5 This is a schematic diagram showing the moving disk 11 in the extreme position along the counterclockwise direction in this embodiment. Figure 5 The spiral line at the center of the top view indicates the subsequent rotation direction and range of the moving disk 11. That is, after the moving disk 11 is at the extreme position in the counterclockwise direction, it can only rotate in the opposite direction in the clockwise direction, and the rotation range is greater than 360 degrees and less than 720 degrees.

[0040] In this embodiment, starting from the middle position of the stop mechanism in the horizontal arm 2, the range of counterclockwise rotation of the moving plate 11 is approximately 360 degrees minus half the central angle occupied by the horizontal arm 2; similarly, starting from the middle position of the stop mechanism in the horizontal arm 2, the range of clockwise rotation of the moving plate 11 is also approximately 360 degrees minus half the central angle occupied by the horizontal arm 2; in total, the range of rotation of the moving plate 11 is approximately 720 degrees minus the central angle occupied by the horizontal arm 2.

[0041] During debugging of this embodiment, attention should be paid to the position of the stop mechanism, the range of the limit, and the relationship between the height of the cross arm. It is recommended to refer to... Figure 4-5 Configure it.

[0042] In this embodiment, the horizontal arm proximity sensor 8 and the stop proximity sensor 10 are Hall sensors that are sensitive to magnets. They can be replaced with other types of proximity sensors, but care should be taken to match the corresponding detection target.

[0043] One variation of this embodiment involves arranging two sets of rocking mechanisms along the circumference of the fixed plate, with the axes of the two rocking mechanisms forming a certain central angle with the fixed plate. With this mechanism, the rotation range of the moving plate is approximately 720 degrees minus the central angle occupied by the two sets of horizontal arms, and then minus the central angle formed by the axes of the two rocking mechanisms and the fixed plate. This implementation is suitable for situations where the fixed and moving plates are relatively large, and where strict control of the moving plate's rotation angle is required.

[0044] It should be noted that the "fixed" in "fixed plate" in this invention does not mean that the fixed plate is absolutely fixed relative to the ground, but rather that the fixed plate is fixed relative to the moving plate, that is, the moving plate can rotate relative to the fixed plate. Another variation of this embodiment is that the fixed plate is not fixed relative to the ground, and the axis of the fixed plate has an angle with the ground, and the angle may change. In this case, the center of gravity of the horizontal arm 2 should be placed on the axis of the rotating shaft 3.

[0045] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electromechanical limit device for a rotation angle of more than 360 degrees, characterized in that The invention relates to a swing mechanism, comprising a fixed disc, a swing mechanism, a movable disc, a stop mechanism, the swing mechanism comprising a cross arm and a rotating shaft, the stop mechanism comprising a stop seat, a steel ball, a buffer rod and a first detection target, the movable disc being rotatable about its own axis relative to the fixed disc, the cross arm being rotatable about the rotating shaft, the axis of the rotating shaft being perpendicular to the axis of the movable disc, the rotating shaft being connected to the fixed disc via a bearing seat, the cross arm having a second detection target at each end, the stop seat being connected to the movable disc, the stop seat having a longitudinal hole with its axis extending in the vertical direction, the steel ball being movable in the longitudinal hole in the axial direction, the hole diameter of the longitudinal hole being smaller than the diameter of the steel ball, a steel ball spring being arranged above the steel ball, the force of the steel ball spring pushing the steel ball towards the hole, the stop seat having a transverse hole extending in the horizontal direction, the buffer rod being movable in the transverse hole in the horizontal direction, an energy absorbing spring being arranged between the stop seat and the buffer rod, the energy absorbing spring absorbing the kinetic energy of the movable disc when the buffer rod moves in the transverse hole, the fixed disc having a cross arm proximity sensor at each end near the cross arm for detecting the second detection target, the cross arm having a stop proximity sensor at each end for detecting the first detection target.

2. The electromechanical stop of claim 1, wherein, When the cross arm is horizontal, the bottom of the steel ball is lower than the upper surface of the cross arm, when the stop mechanism rotates to the position of the cross arm, the upper surface of the cross arm pushes the steel ball into the stop seat, the steel ball spring is further compressed.

3. An electromechanical stop as claimed in claim 1 or 2, characterised in that, The first detection target is a stop magnet, the second detection target is a cross arm magnet, the cross arm proximity sensor and the stop proximity sensor are both Hall sensors sensitive to magnets.

4. The electromechanical stop of claim 1, wherein, The fixed disc has a fixed disc magnet at the position in contact with the cross arm, before the steel ball is completely pushed into the stop seat, the torque of the elastic force of the steel ball spring on the rotating shaft of the cross arm is greater than the torque of the magnetic force of the fixed disc magnet on the rotating shaft of the cross arm.

5. The electromechanical limit device of claim 4, wherein, The cross arm is made of steel or has magnetic material at the position in contact with the fixed disc.

6. An electromechanical stop as claimed in claim 4 or 5, characterised in that, When one end of the cross arm moves downwards and approaches the fixed disc, the fixed disc magnet near the end attracts the end to the fixed disc, the cross arm proximity sensor near the end obtains a proximity signal, the other end of the cross arm moves upwards and approaches the movable disc, the stop proximity sensor mounted on the end enters a state in which it can detect the position of the stop mechanism.

7. The electromechanical position-limiting device of claim 1, wherein, The energy absorbing spring is a compression spring, a tension spring, a disc spring, a damper or a combination thereof, the energy storage and energy consumption of the energy absorbing spring and the movement stroke of the buffer rod are determined according to the limit value of the kinetic energy of the movable disc.

8. The electromechanical position-limiting device of claim 1, wherein, When the fixed disc is fixed relative to the ground, the center of gravity of the cross arm is higher than the axis of the rotating shaft, in this state, the cross arm is in a statically indeterminate state when it is horizontal.

9. The electromechanical limit device of claim 8, wherein, When the stop mechanism is in the middle position of the cross arm, the cross arm is horizontal, since the cross arm is in a statically indeterminate state, when the stop mechanism moves away from the middle position of the cross arm, the cross arm will swing in the direction away from the stop mechanism, due to the pressure of the steel ball, the cross arm will swing until one end of the cross arm contacts the fixed disc.

10. The electromechanical position-limiting device of claim 1, wherein, A plurality of sets of swing mechanisms are arranged along the circumference of the fixed disc.

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