A large antenna with a friction pendulum shock-absorbing structure

Abstract

The present invention discloses a large antenna with a friction pendulum shock-absorbing structure, which belongs to the field of antenna technology. The antenna includes an upper seat plate, a shock-absorbing pendulum and a lower seat plate which are arranged in sequence from top to bottom; the bottom surface of the upper seat plate and the bottom surface of the shock-absorbing pendulum are both smooth convex surfaces, the top surface of the shock-absorbing pendulum and the top surface of the lower seat plate are both smooth concave surfaces, and the smooth concave surfaces and the smooth convex surfaces correspond to each other one by one; a shock-isolating block is also provided on the top of the lower seat plate, and the shock-isolating block and the lower seat plate are fixed by a shear pin perpendicular to the two; the shock-absorbing pendulum is located in the area formed by the shock-absorbing block, and the shock-absorbing pendulum and the shock-absorbing block are in close contact; the edge of the top of the lower seat plate is provided with a limiting wall for constraining the horizontal movement of the upper seat plate. The present invention has a shock-isolating and shock-absorbing effect on the reflector, thereby reducing the occurrence of risks and reducing the loss of damage; at the same time, it has the characteristics of low cost, high reliability, and easy installation and maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and in particular to a large antenna with a friction pendulum shock absorption structure. Background Art

[0002] Typically, the main structure of a large antenna consists of two main parts: the mount and the reflector. The reflector is the functional portion of the antenna. The reflector carries a large reflective surface to receive and collect electromagnetic wave signals from deep space. This complex structure and the use of several expensive and sophisticated devices are the main drawbacks of the antenna. The mount, on the other hand, is a relatively simple steel support component, supporting and driving the reflector in pitch and azimuth motion.

[0003] Over the past few decades, humanity has built an increasing number of large telescope antennas, but their designs remain largely the same, with few innovations. Examples include the 65-meter Tianma Telescope in Shanghai, the 66-meter Deep Space Exploration Antenna in Jiamusi, the 70-caliber antenna in Tianjin, and the 120-meter antenna currently under construction in Yunnan. These traditional large antenna structures are characterized by their immense height, weight, and size. The reflector is connected to the mounting frame at only two elevation axis locations. This design approach rarely considers earthquake damage to the antenna structure, nor does it incorporate proactive vibration mitigation measures. Furthermore, the site selection for large telescope antennas generally prioritizes a pristine electromagnetic environment far from modern human habitation and the need for large-scale observations across multiple antennas, rather than primarily considering the impact of earthquakes. Therefore, in addition to some completed large antennas, some unfinished equipment may also be located in seismic zones, creating a potential for damage. In the event of an earthquake, the enormous height, weight, and volume of these large antennas would directly bear the shock and vibration of the seismic waves, making them susceptible to deformation, damage, and collapse, with devastating consequences.

[0004] In recent years, China's seismic isolation and vibration reduction technologies for combating earthquake damage have made significant progress and are increasingly being applied to high-rise buildings and large-scale equipment. In particular, the friction pendulum isolation and vibration reduction structure has become increasingly mature in recent years. This carefully designed curved sliding surface structure can extend the structure's natural vibration period, providing a shock-absorbing effect. Its rationally designed sliding surface friction coefficient effectively dissipates energy, providing a high load-bearing capacity and a reset function. Furthermore, it is lightweight, easy to manufacture, and simple to install and maintain. Summary of the Invention

[0005] In light of this, the present invention provides a large antenna with a friction pendulum shock-absorbing structure. This structure effectively isolates and dampens the antenna structure, particularly the reflector, during earthquakes, thereby reducing risks and losses. It also offers low cost, high reliability, and ease of installation and maintenance.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A large antenna with a friction pendulum shock absorption structure comprises a reflector and a base frame; the friction pendulum shock absorption structure is arranged between the reflector and the base frame.

[0008] Furthermore, the friction pendulum shock absorption structure is a simple pendulum structure or a compound pendulum structure.

[0009] Furthermore, the friction pendulum shock-absorbing structure includes an upper seat plate, a shock-absorbing pendulum and a lower seat plate arranged in sequence from top to bottom; the bottom surface of the upper seat plate and the bottom surface of the shock-absorbing pendulum are both smooth convex surfaces, the top surface of the shock-absorbing pendulum and the top surface of the lower seat plate are both smooth concave surfaces, and the smooth concave surfaces and the smooth convex surfaces correspond one to one respectively; the top of the lower seat plate is also provided with a shock-isolating block, and the shock-isolating block and the lower seat plate are fixed by a shear pin that is vertical and passes through the two; the shock-absorbing pendulum is located in the area formed by the shock-absorbing block, and the shock-absorbing pendulum and the shock-isolating block are in close contact; the edge of the top of the lower seat plate is provided with a limiting wall for constraining the horizontal movement of the upper seat plate.

[0010] Furthermore, the maximum height of the seismic isolation block is lower than the height of the limiting wall, and the top of the upper seat plate is higher than the limiting wall; one side of the upper seat plate is provided with a downward extension, which is located in the area formed by the limiting wall and its outward movement tendency is constrained by the limiting wall.

[0011] Furthermore, a shock-absorbing slide plate for reducing friction is provided between the upper seat plate and the shock-absorbing pendulum, and between the shock-absorbing pendulum and the lower seat plate.

[0012] Furthermore, a number of isolation blocks are provided along the center line of the concave surface of the lower seat plate, where a≥1; and the shear pins are provided on the outer isolation blocks.

[0013] Furthermore, it also includes a rope and a rope power device for pulling the rope; a pitch axis seat is provided on the top of the upper seat plate of the friction pendulum shock-absorbing structure, and the bottom of the reflector is fixed to the pitch axis; the rope power device is provided at the bottom of the seat frame, one end of the rope is connected to the corresponding rope power device, and the other end is connected to the reflector above the rope power device; the rope power device drives the pitch movement of the reflector through the rope.

[0014] The beneficial effects of the above technical solution of the present invention are:

[0015] 1. The friction pendulum shock-absorbing structure between the reflector and the frame of the present invention has a good effect of isolating and absorbing shock for the reflector, thereby reducing the damage to the reflector caused by earthquakes.

[0016] 2. The shock-absorbing pendulum of the present invention has a self-resetting function under the action of its own gravity, is highly reliable, and is easy to install and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of an embodiment of the present invention.

[0018] Figure 2 2 is a half-section schematic diagram of the friction pendulum damping structure in an embodiment of the present invention.

[0019] Figure 3 It is a side view of a large antenna used in an embodiment of the present invention.

[0020] Figure 4 yes Figure 3 Schematic diagram of the stabilizing cable structure.

[0021] Figure 5 yes Figure 3 Schematic diagram of the cable power device structure.

[0022] Figure 6 yes Figure 3 Schematic diagram of the pitch accuracy control structure.

[0023] Figure 7 yes Figure 3 Schematic diagram of the pitch limit structure.

[0024] In the figure: 1. Frame, 1.1. Roller, 1.2. Axle seat, 2. Reflector, 3. Cable, 3.1. Cable power device, 3.2. Cable force structure, 3.1.1. Motor reducer combination, 3.1.2. Hoist drum, 3.1.4. Tension sensor, 3.1.5. Terminal, 4. Foundation, 4.1. Annular rail, 5. Cable stabilizing structure, 5.1. Pulley, 5.2. Tension sensor, 5.3. Terminal, 5.4. Elastic Components: 6. Pitch precision control structure; 6.1. Meshing gear; 6.2. Small fan gear; 6.3. Annular code disk; 7. Pitch limit structure; 7.1. Main steel frame; 7.2. Buffer platform; 7.3. Buffer unit; 7.4. Locking mechanism; 8. Friction pendulum shock absorption structure; 8.1 Upper seat plate; 8.2 Lower seat plate; 8.3 Shock absorption pendulum; 8.4 Shock absorption slide plate; 8.5 Shock isolation block; 8.6 Shear pin; 8.7 Limiting wall. DETAILED DESCRIPTION

[0025] The following specific embodiments are provided to further illustrate the present invention. Of course, the following specific embodiments are merely provided to illustrate different aspects of the present invention and should not be construed as limiting the scope of the present invention.

[0026] A large antenna with a friction pendulum shock absorption structure comprises a reflector and a base frame; the friction pendulum shock absorption structure is arranged between the reflector and the base frame.

[0027] Furthermore, the friction pendulum shock absorption structure is a simple pendulum structure or a compound pendulum structure.

[0028] Furthermore, the friction pendulum shock-absorbing structure includes an upper seat plate, a shock-absorbing pendulum and a lower seat plate arranged in sequence from top to bottom; the bottom surface of the upper seat plate and the bottom surface of the shock-absorbing pendulum are both smooth convex surfaces, the top surface of the shock-absorbing pendulum and the top surface of the lower seat plate are both smooth concave surfaces, and the smooth concave surfaces and the smooth convex surfaces correspond one to one respectively; the top of the lower seat plate is also provided with a shock-isolating block, and the shock-isolating block and the lower seat plate are fixed by a shear pin that is vertical and passes through the two; the shock-absorbing pendulum is located in the area formed by the shock-absorbing block, and the shock-absorbing pendulum and the shock-isolating block are in close contact; the edge of the top of the lower seat plate is provided with a limiting wall for constraining the horizontal movement of the upper seat plate.

[0029] Furthermore, the maximum height of the seismic isolation block is lower than the height of the limiting wall, and the top of the upper seat plate is higher than the limiting wall; one side of the upper seat plate is provided with a downward extension, which is located in the area formed by the limiting wall and its outward movement tendency is constrained by the limiting wall.

[0030] Furthermore, a shock-absorbing slide plate for reducing friction is provided between the upper seat plate and the shock-absorbing pendulum, and between the shock-absorbing pendulum and the lower seat plate.

[0031] Furthermore, a number of isolation blocks are provided along the center line of the concave surface of the lower seat plate, where a≥1; and the shear pins are provided on the outer isolation blocks.

[0032] Furthermore, it also includes a rope and a rope power device for pulling the rope; a pitch axis seat is provided on the top of the upper seat plate of the friction pendulum shock-absorbing structure, and the bottom of the reflector is fixed to the pitch axis; the rope power device is provided at the bottom of the seat frame, one end of the rope is connected to the corresponding rope power device, and the other end is connected to the reflector above the rope power device; the rope power device drives the pitch movement of the reflector through the rope.

[0033] The following is a specific embodiment:

[0034] Reference Figures 1 to 7 The friction pendulum damping structure of this embodiment includes an upper seat plate, a lower seat plate, a damping pendulum, a damping slide plate, a seismic isolation block, a shear pin, and a limiting wall. The damping pendulum and the damping slide plate are used in conjunction with each other between the upper and lower seat plates. The seismic isolation blocks are distributed around the damping pendulum and fit closely to the lower seat plate. The shear pins secure the seismic isolation blocks to the lower seat plate. The limiting wall is fixed to the outer side of the lower seat plate and extends upward to a certain height, forming a semi-open structure.

[0035] This embodiment has a better effect when installed on a large cable-driven pitching radio telescope. The large radio telescope mainly includes a mount 1, a reflector 2, a cable 3 and a cable driving device.

[0036] The frame 1 is a large, spatial steel skeleton structure. A set of rollers 1.1 are located at its base, enabling its azimuth rotation. Two pitch axis mounts 1.2 are located at its top, supporting the reflector and cooperating to achieve pitch rotation of the reflector relative to the pitch axis (which can be viewed as the line connecting the two pitch axis mounts).

[0037] The reflector includes a reflective surface and a spatial grid supporting the reflective surface. The reflector is mounted on a frame and has rotational freedom. A pitch axis mechanism is provided at its lower portion. This mechanism mates with the pitch axis seat of the frame, allowing the reflector to rotate freely relative to the frame along the pitch axis.

[0038] The reflector and mount structure are designed to be bidirectionally symmetrical. That is, when the reflector points vertically upward, the telescope's main structure is symmetrical both along the pitch axis and perpendicular to it. The line connecting the two pitch axis mounts on the mount (the pitch axis) is parallel to the earth. The reflector's optical axis and the pitch axis are perpendicular and intersecting, and the pitch axis and the azimuth axis are also perpendicular and intersecting. This symmetrical structure allows the reflector to rotate relative to the mount with a comparable degree of bilateral symmetry along the pitch axis.

[0039] The cable drive device mainly includes a cable power device 3.1 and a cable force-bearing structure 3.2. The cable drive device realizes the pitch motion purpose of the reflector rotating to the same degree on both sides of the pitch axis. The cable power device is symmetrically arranged on both sides of the bottom of the seat frame. The cable power device adopts a motor servo winch structure, which mainly includes a motor reducer combination 3.1.1, a winch drum 3.1.2, a cable 3 wound on the winch drum, a tension sensor 3.1.4 and a terminal 3.1.5. The motor reducer combination drives the winch drum to rotate in the forward and reverse directions, thereby driving the cable wound on the winch drum to extend or shorten. The tension sensor is used to monitor whether the tension of the cable is uniform and within a reasonable range. Corresponding to the cable power device on the seat frame, the cable force-bearing structure is arranged at the bottom of the reflector and is also symmetrically distributed on both sides. The cable power device and the cable force-bearing structure are connected by a cable.

[0040] One or more cables are provided. Multiple cables correspond to more than one cable drive device. A safety cable is provided among the multiple cables. It does not primarily provide tension during normal use of the telescope, but serves as a safety cable in special circumstances such as when other cables break, ensuring that the reflector can safely return to a stable position in extreme situations.

[0041] The large radio telescope further comprises a foundation 4 on which a circular steel rail 4.1 is provided, corresponding to the roller mechanism at the bottom of the frame, to enable the frame to rotate on the circular steel rail.

[0042] The large radio telescope also includes a cable stabilization structure 5. The cable stabilization structure is installed on the base frame and is connected to the cable by a pulley 5.1 assembly at the protruding end. The cable and the protruding end are in contact through the pulley and are not fixed in position. The cable stabilization mechanism is provided with a tension sensor 5.2 for tension and extension length at the protruding end and a terminal 5.3 connected to the sensor to adjust the uniformity of the tension of each cable in real time. For the case of multiple cables, there is also an elastic component. Its structure is similar to the constraints between high-altitude high-voltage wires, which is used to limit the position and distance between multiple cables near a cross section. Since the relative angles and distances between multiple cables will change during the pitch movement, elastic components 5.4 such as springs are used to adjust between different constraint points. The function of the cable stabilization structure is to overcome adverse conditions such as abnormal shaking and vibration of the cables that may occur in strong winds, equipment vibrations, etc.

[0043] The large radio telescope also includes a pitch precision control structure 6, which is a small fan gear mechanism, mainly including a meshing gear 6.1 and a small fan gear 6.2. The small fan gear is reversely installed at the bottom of the reflector, passing through and coaxial with the pitch axis; the meshing gear is installed on the seat and meshes with the small fan gear, and the torque is provided by a motor reducer combination or a damping motor. During the pitch movement of the reflector, the cable drive device generates a huge pulling force to cause the reflector to rotate along the pitch axis, and at the same time the small fan gear mechanism generates a certain reverse counteracting torque. Through this matching of one positive and one negative torque, the precise control of the pitch angle of the reflector is assisted, making the pitch movement of the reflector more stable. At the same time, the mechanism can also assist in outputting rotation data. For example, the annular code disk 6.3 fixed on the small fan gear can also play a certain braking role, thereby being used to lock the pitch attitude of the reflector.

[0044] In terms of motion properties, the pitch precision control structure is rigid compared to the cable drive, while the latter is flexible. In terms of motion contribution, the two are equivalent to a "scholar" and a "strongman" respectively. The main driving force during the pitch motion is provided by the cable drive, and when the cable drive's precision control capability is insufficient, the pitch precision control mechanism plays a role.

[0045] The pitch precision control mechanism may also be a hydraulic or lead screw or other precisely controllable servo control mechanism.

[0046] The large radio telescope also includes a pitch limit structure 7. There are two pitch limit structures, which are symmetrically installed on both sides of the mount, corresponding to their pitch angle limits. The pitch limit structure mainly includes a main steel frame 7.1, a buffer platform 7.2, a buffer unit 7.3, a locking mechanism 7.4 and other parts. The contact platform is located at the protruding end of the main steel frame, and the buffer unit and the locking mechanism are respectively installed on the contact platform. When the pitch movement is about to reach the limit position, the predetermined protruding position of the reflector will first contact the buffer mechanism of the pitch limit device, and after its impact force and speed are buffered, it reaches the limit position and stops moving. At this time, the locking mechanism can effectively lock the reflector with great force.

[0047] A large radio telescope can achieve a pitch movement of about ±85° with the reflector pointing vertically to the sky at 0°.

[0048] When the telescope is observing the sky, the roller mechanism on the mount rotates on circular steel rails on the foundation, achieving azimuth movement of the entire telescope. The cable drive and various auxiliary mechanisms achieve the pitch movement of the reflector. Both azimuth and pitch movements have the functions of acceleration, deceleration, positioning, and braking. The two movements work together to achieve precise pointing of the reflector.

[0049] Pitch movement is accomplished by cable drives on both sides. The winch on one side retracts the cable while the other side releases it, achieving the reflector's pitch. The reverse motion achieves the reflector's pitch position. At the extremes of pitch movement, the reflector is positioned at its lowest angle on either side of the mount. Corresponding pitch limits on each side ensure the safety of the telescope antenna at these extremes.

[0050] The upper seat plate of the friction pendulum damping structure is connected to the pitch axis seat, and the lower seat plate is connected to the seat frame.

[0051] The reflector is connected to two pitch axis mounts via two pitch axes. The two pitch axis mounts are mounted on top of the upper base plates of the two friction pendulum damping structures. The lower base plates of the two friction pendulum damping structures are mounted on either side of the upper end of the frame. The frame rests on foundation rails and can rotate in azimuth. A cable drive is mounted on the frame and connected to the reflector via a flexible cable within the device. The cable drive utilizes its bidirectional traction to achieve pitch motion of the reflector relative to the frame about the pitch axis.

[0052] The friction pendulum shock-absorbing structure 8 mainly includes an upper seat plate 8.1, a lower seat plate 8.2, a shock-absorbing pendulum 8.3, a shock-absorbing slide plate 8.4, a shock-isolating block 8.5, a shear pin 8.6, a limiting wall 8.7 and other parts. The upper seat plate 8.1 is connected to the pitch axis seat 2, and the lower seat plate 8.2 is connected to the seat frame 6. The shock-absorbing pendulum 8.3 and the shock-absorbing slide plate 4.4 are used in conjunction with the upper and lower seat plates. The shock-isolating block 4.5 is distributed around the shock-absorbing pendulum 8.3 and fits with the lower seat plate 8.2. The shear pin 8.6 passes through the upper seat plate 8.1 to fix the shock-isolating block 8.5 on the lower seat plate 8.2. The limiting wall 8.7 is fixed to the outside of the lower seat plate 8.2, extending upward to a certain height, and presenting a semi-open structure.

[0053] When there is no earthquake, due to the effect of the shear pin, the friction pendulum shock absorption structure is equivalent to a fixed support transition section and does not affect the normal use of the antenna.

[0054] During an earthquake, the antenna structure shakes as a whole. As the earthquake's intensity increases, when the ground shaking reaches a certain level, the shear pins in the friction pendulum's damping structure shear off, and the pendulum begins to swing along with the base frame. The carefully designed curved sliding surfaces at the junction of the upper and lower base plates and the damping pendulum extend the structure's natural vibration period and, by utilizing the principle of kinetic and potential energy conversion, provide a certain degree of shock absorption.

[0055] In this structure, when the earthquake intensity is excessive, the limiting walls restrict the upper seat's range of motion both externally and vertically, preventing it from exceeding the limits set by the limiting walls. Simultaneously, the cables of the cable drive exert a downward pull on the reflector, which increases as the upward displacement of the reflector caused by the earthquake vibrations increases. This counteracts the friction pendulum's tendency to move up and down, restraining it and pulling it back to its original position, thus preventing it from tipping over.

[0056] In general, compared to existing large telescope antennas, the main structure of this patented invention primarily adds a specially constructed friction pendulum transition section to the top of the existing mount. Furthermore, the existing sector gear-driven pitch motion is replaced by a bidirectional cable-driven pitch motion. This technical solution effectively isolates and protects the reflector, while also being low-cost and easy to install and maintain.

[0057] It should be understood that the above description of the specific implementation methods of this patent is merely an exemplary description listed to facilitate ordinary technicians in this field to understand the patent solution, and does not imply that the scope of protection of this patent is limited to these individual examples. Ordinary technicians in this field can fully understand the technical solution of this patent and, without any creative work, obtain more specific implementation methods by combining technical features, replacing some technical features, adding more technical features, etc. to the examples listed in this patent. All these specific implementation methods are within the scope of the claims of this patent. Therefore, these new specific implementation methods should also be within the scope of protection of this patent.

[0058] In addition, for the purpose of simplifying the description, this patent may not list some common specific implementation plans. These plans can be naturally thought of by ordinary technicians in this field after understanding the technical solutions of this patent. Obviously, these plans should also be included in the scope of protection of this patent.

Claims

1. A large antenna with a friction pendulum shock-absorbing structure, comprising a reflector (2) and a mount (1); characterized in that: A friction pendulum shock absorbing structure (8) is provided between the reflector and the seat frame; the friction pendulum shock absorbing structure is a simple pendulum structure or a compound pendulum structure; the friction pendulum shock absorbing structure comprises an upper seat plate (8.1), a shock absorbing pendulum (8.3) and a lower seat plate (8.2) arranged in sequence from top to bottom; the bottom surface of the upper seat plate and the bottom surface of the shock absorbing pendulum are both smooth convex surfaces, the top surface of the shock absorbing pendulum and the top surface of the lower seat plate are both smooth concave surfaces, and the smooth concave surfaces and the smooth convex surfaces correspond to each other one by one; a shock isolation block is also provided on the top of the lower seat plate, and the shock isolation block (8.5) and the lower seat plate are connected by a shear pin that is vertical and penetrates both. (8.6) fixed; the shock-absorbing pendulum is located in the area surrounded by the isolation block, and the shock-absorbing pendulum and the isolation block are in close contact; the edge of the top of the lower seat plate is provided with a limiting wall (8.7) for restricting the horizontal movement of the upper seat plate; the maximum height of the isolation block is lower than the height of the limiting wall, and the top of the upper seat plate is higher than the limiting wall; one side of the upper seat plate is provided with a downward extension, the extension is located in the area formed by the limiting wall, and its outward movement tendency is restricted by the limiting wall; a shock-absorbing slide plate (8.4) for reducing friction is provided between the upper seat plate and the shock-absorbing pendulum and between the shock-absorbing pendulum and the lower seat plate.

2. A large antenna with a friction pendulum shock-absorbing structure according to claim 1, characterized in that: There are multiple isolation blocks; the multiple isolation blocks form a circle, a≥1; the shear pins are arranged on the isolation blocks in the outermost circle.

3. The large antenna with a friction pendulum shock-absorbing structure according to claim 1, characterized in that: It also includes a cable and a cable power device for pulling the cable; a pitch axis seat is provided on the top of the upper seat plate of the friction pendulum damping structure, and the bottom of the reflector is fixed to the pitch axis; the cable power device is provided at the bottom of the seat frame, one end of the cable is connected to the corresponding cable power device, and the other end is connected to the reflector above the cable power device; The cable power device drives the reflector to move in elevation through the cable.

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