Self-rotating cable truss feed support structure

Abstract

The self-rotating cable truss feed support structure designed by the present invention includes four parts: a support frame, a main cable, a strut and a cable truss, wherein the strut includes two groups of main struts and four groups of auxiliary struts, and the cable truss includes three groups of chords and two parts of a web. The cable truss is hinged to the support frames at both ends, and the support frames at both ends are hinged to the ground, and a main cable at each end is hinged to the ground. The two middle groups of main support rods and the two groups of auxiliary support rods on both sides jointly provide vertical support for the cable truss, and the lower end of the support is hinged to the reflecting surface. The present invention can be applied to the feed support of a columnar parabolic antenna, with a simple structure and light weight, and is particularly suitable for antennas with a large span, minimizing the shielding of the antenna by the feed support, and the self-rotation of the cable truss can be achieved through the middle rigid support rod without the need for an additional drive system.

Description

Technical Field

[0001] The invention relates to the technical field of antenna engineering, and in particular to a self-rotating cable truss feed source supporting structure. Background Art

[0002] In order to ensure that the feed is always at the focus of the antenna reflection surface, the existing antenna feed support system needs to rotate with the antenna. Therefore, the feed must be directly supported on the antenna reflection surface and itself needs to form a rigid structure. For large antennas, in order to control the influence of structural deflection on the phase center position of the feed, it is required to improve the rigidity of the structure, which will lead to an increase in the deadweight of the entire support structure, which further requires the addition of more support structures, resulting in a larger cross-section of the support structure. Excessive supports and larger structures will increase the shielding area and thus affect the electrical performance of the antenna. Summary of the invention

[0003] To solve the above problems, the present invention provides a self-rotating cable truss feed support structure that uses high-strength cables with tensile stress to replace ordinary steel structural parts, thereby reducing the weight and outer contour volume of the feed support structure itself, and enabling the feed to rotate with the antenna reflecting surface without the need for additional power.

[0004] In order to achieve the above-mentioned purpose, the self-rotating cable truss feed support structure designed in the present invention includes four parts: a support frame, a main cable, a strut and a cable truss. Both ends of the cable truss are hinged to the support frame, the bottom of the support frame is hinged to the ground, and the outer side of the support frame is connected to the main cable with prestress so that the support frame tilts outward, the other end of the main cable is hinged to the ground, and the middle of the cable truss is connected to the main support rods arranged in groups to provide vertical support for the cable truss, and the lower end of the main support rod is hinged to the antenna reflection surface. The cable truss is composed of a number of chords and webs arranged between the chords. The several chords converge at the two ends of the cable truss to the straight line where the focus of the antenna reflection surface is located, and the antenna feed is arranged on the circumcenter of the cross section of the cable truss. The characteristic of this structure is that the prestress applied by the main cable is used to pull the support frame outward, thereby providing tensioning force for the chords of the cable truss. The tensioned chords work together with the web members hinged to them to form a cable truss that can withstand external loads. At the same time, the middle part of the cable truss is supported by the main support rods to reduce the deflection of the middle part of the cable truss.

[0005] A further solution is that the cable truss is connected to a group of auxiliary support rods, which are symmetrically arranged on both sides of the main support rod, and the lower ends of the auxiliary support rods are hinged to the antenna reflection surface. Through the support of the auxiliary support rods, the deflection of the cable truss structure can be further reduced, providing low-deflection feed support for the long-distance cylindrical parabola.

[0006] A further solution is that the main support rod is rigidly connected to the cable truss; the auxiliary support rod is hinged to the circumcenter of the cable truss cross section. The rigid connection can provide better support force, and the hinged structure of the auxiliary support rod can make the cable truss rotate with the rotation of the middle main support rod and the auxiliary support rods on both sides rotate with the rotation of the lower reflective surface relatively independently without interfering with each other.

[0007] A further solution is that there are three chords and the cross section of the cable truss is triangular, so as to form a relatively stable structure with the web rod.

[0008] A further solution is that the main support rods arranged in groups are connected to the two lower vertices of the cross-sectional triangle of the cable truss, so as to ensure that when the antenna reflector rotates, the cable truss can be driven to rotate through the main support rods.

[0009] A further solution is that the main support rods are divided into two groups, each corresponding to an antenna reflector, and the auxiliary support rods are divided into four groups, which are symmetrically arranged on both sides of the main support rods and correspond to two antenna reflectors respectively, thereby forming an antenna array, realizing the function of the antenna, and further reducing the number of the entire support structure.

[0010] Compared with the prior art, the self-rotating cable truss feed support structure designed by the present invention has a cable truss structure as the main body, and the cable truss structure can rotate axially around the support point on the support frame, and use the main cable to form tension, and use the support frame, main support rod and auxiliary support rod on both sides to form vertical support to ensure the stability of the structure. At the same time, different connection modes and connection positions of the main support rod and the auxiliary support rod with the cable truss are designed, which not only ensures the support effect, but also ensures that the rotations of different angles between the antenna reflective surfaces will not interfere with each other. In summary, the present invention has the following characteristics: it overcomes the disadvantages that it is difficult to form tension stress on the reflective surface, and the feed support must rotate with the reflective surface; it can be applied to the feed support of a longitudinally long cylindrical parabolic antenna, and compared with the ordinary support structure, it greatly reduces the dead weight of the structure; if the reflective surface is too long and needs to be driven by a reflector unit, the number of reflector units can be increased within a certain range, and the rotation of the feed support frame will not be affected by the rotation error between different reflector units, which greatly simplifies the motion control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is an axonometric view of Example 1.

[0012] Figure 2 It is a cross-sectional view of the connection between the main support rod and the cable truss in Example 1.

[0013] Figure 3 It is a cross-sectional view of the connection between the auxiliary support rod and the cable truss in Example 1.

[0014] Figure 4 yes Figure 3 Side view of. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0016] Example 1.

[0017] like Figure 1 As shown, the self-rotating cable truss feed source support structure described in this embodiment includes four parts: a support frame 1, a main cable 2, a strut and a cable truss 3. The cable truss 3 is hinged to the support frames 1 at both ends, and the support frames 1 at both ends are hinged to the ground, and one main cable 2 at each end is hinged to the ground. The two sets of main support rods 4 in the middle and the two sets of auxiliary support rods 5 on both sides jointly provide vertical support for the cable truss 3, and the lower ends of the main support rods 4 and the auxiliary support rods 5 are both hinged to the antenna reflector 6.

[0018] The cable truss 3 has a cross-sectional structure of three chords 7 forming a triangle, and both ends of the three chords 7 should converge to the straight line where the focus of the antenna reflector 6, i.e., the parabola, is located, i.e., the rotation axis at the connection between the two ends of the cable truss 3 and the support frame 1, and its lateral projection coincides with the circumcenter 9 of the triangle. The chords 7 arranged at the vertices of the triangle form the cable truss 3 together with the web members 8 arranged in a certain pattern. Prestress is applied through the main cables 2 at both ends to pull the support frame 1 outward, thereby providing tensioning force for the chords 7 of the cable truss 3. The tensioned chords 7 and the web members 8 hinged thereon work together to form a cable truss 3 that can bear the weight of the feed source.

[0019] like Figure 2 As shown, the upper end of the main support rod 4 is rigidly connected to the two lower fixed points of the triangular cross-section of the cable truss 3, and the lower end of the main support rod 4 is hinged to the antenna reflector. On the one hand, it provides vertical support force to the cable truss 3 and controls the deflection of the cable truss 3 under the action of the feed source and other loads. On the other hand, it transmits the movement of the lower reflector to the cable truss 3, driving the cable truss 3 to rotate along the circumcenter 9 of the triangle (the focus of the parabola), and the antenna feed source is set at the circumcenter 9 of the cross-section of the cable truss 3.

[0020] like Figure 3 , Figure 4 As shown, the auxiliary support rod 5 is connected to the cable truss 3 at the circumcenter 9 (focus of the parabola) of the triangular cross-section through a revolute pair, and the lower end is hinged to the antenna reflector 6. The auxiliary support rod 5 can provide vertical support force to the cable truss 3, but can rotate independently with the cable truss 3. Such a design can provide support for multiple independently rotating reflectors without interfering with each other.

[0021] Figures 1 to 3As shown, in this embodiment, the total length of the cylindrical parabolic antenna is 142m, the diameter is 40m, the focal length of the parabola is 17m, and the feed source is arranged every 0.5m along the longitudinal direction, and the cylindrical parabolic antenna reflector is divided into three reflector units with a length of 44m along the longitudinal direction. The reflector unit can slide along the lower arc track and rotate positive and negative 45 degrees to the left and right. The spacing between the ground brackets at both ends of the cable truss 3 is 150m, and the cross-section of the cable truss 3 is a regular triangle with a side length of 2m. The cable truss 3 rotates with the middle reflector unit, and the antenna reflection surface 6 of the other two reflector units on the other two sides rotates to drive the auxiliary support to rotate. Even if there is an error in the rotation speed between the multiple reflector units, they will not interfere with each other. As the reflector unit rotates, the reaction force transmitted to the reflector by the middle support rod will change, but since this design is directly transmitted to the antenna support through the basic frame, the deformation of the reflector unit has almost no effect on the position of the feed source. At the same time, high-strength cables are used, and the feed source support structure not only reduces its own weight and volume, but also improves the overall rigidity of the structure, and reduces the number of intermediate struts, so that the phase center of the feed source can accurately fall on the focal position, while reducing the impact of excessive feed source support on the surface accuracy of the reflector. In addition, the new feed source rotation method not only ensures the synchronous rotation of the feed source and the reflector, but also saves the drive system of the feed source.

Claims

1. A self-rotating cable truss feed source support structure, comprising a support frame, a main cable, a strut and a cable truss, wherein both ends of the cable truss are hinged to the support frame, the bottom of the support frame is hinged to the ground, and the outer side of the support frame is connected to a main cable with prestress so that the support frame tilts outward, the other end of the main cable is hinged to the ground, the middle of the cable truss is connected to a main support rod arranged in a group to provide vertical support for the cable truss, and the lower end of the main support rod is hinged to the antenna reflection surface, the cable truss is composed of a plurality of chords and a web rod arranged between the chords, the plurality of chords are gathered at both ends of the cable truss to a straight line where the focus of the antenna reflection surface is located, and the phase center of the antenna feed source is arranged at the circumcenter of the cross section of the cable truss; The cable truss is connected to a group of auxiliary support rods, which are symmetrically arranged on both sides of the main support rod, and the lower ends of the auxiliary support rods are hinged to the antenna reflection surface; The main support rod is rigidly connected to the cable truss; the auxiliary support rod is hinged to the circumcenter of the cable truss cross section; There are three chords, and the cross section of the cable truss is a triangle; The main support rods arranged in groups are connected to the two lower vertices of the cross-sectional triangle of the cable truss; The main support rods are divided into two groups and connected to one antenna reflector surface respectively. The auxiliary support rods are divided into four groups and symmetrically arranged on both sides of the main support rods and correspond to two antenna reflectors respectively.

Images