EP0364974B1 - Antenna support adjustable in azimuth and elevation - Google Patents

Description

The present invention relates to an antenna mount and, more particularly, to an azimuth-elevation type mount, that is to say a mount having a vertical axis of rotation, for orienting the antenna in azimuth, and a horizontal axis of rotation, for the orientation of the antenna in elevation.

The invention relates more precisely to an antenna of the azimuth-elevation type cantilevered relative to vertical. In such a case, the antenna support, a part mounted on a vertical base and allowing the antenna to rotate in azimuth poses a problem. Indeed, it must be able to be made free from the base, in order to allow rotation. It must then be secured to the base, in order to prevent any rotation in azimuth of the correctly pointed antenna. From one to the other of these two situations, the elevation angle of the antenna must not change. Without this, any correction of the azimuth would also require a resumption of the elevation, which would considerably complicate the work of the antenna installer. An antenna support constituted, in a conventional manner, essentially by a split cylindrical piece, could not meet this need because any play brought to allow rotation in azimuth would result in a tilting of the cylindrical piece relative to the base and therefore by a displacement in elevation. The antenna support of document FR 2595510, which is a U-shaped gutter pressed against the base by flanges has the same drawback.

The invention therefore relates to an antenna support comprising means such that the elevation of the antenna remains the same, whether free or secured to the base.

According to a characteristic of the invention, the antenna support comprises a mounting plate to which the antenna and a barrel is fixed, and said barrel comprises at least one upper half-collar embracing the base and the arms of which are extend towards the antenna and an upper flange attaching to the upper half-collar to block it on the base, a lower half-collar embracing the base and the arms of which extend in the direction opposite to the antenna and a lower flange which attaches to the lower half-collar to block it on the base, as well as two lateral uprights of sufficient length extending at a certain distance parallel to the axis of the base and each joining, respectively, the end part of an arm of the half-collar higher than the end part located below the preceding one of the half lower collar.

According to another characteristic of the invention, each of the half-collars embraces the base approximately 180 °.

According to another characteristic of the invention, each of the half-collars internally comprises at least one cylindrical bearing surface of limited angular width and height.

According to another characteristic of the invention, each of the half-collars comprises two cylindrical bearings symmetrically disposed with respect to its arms and spaced about 90 ° apart.

According to another characteristic of the invention, the support, apart from the two flanges, is made essentially of a molded metal part and, of the half-collars, only said bearings are machined.

The arrangements which have just been described allow the support, in place on the base, loaded cantilevered by the antenna, to be stressed so that the bearing surface or surfaces provided on the inner surface of the half collars remain in abutment against the cylindrical surface of the base, whether the flanges are tight or not, so that the elevation of the antenna will remain unchanged and keep the fixed value, throughout the azimuth adjustment.

• la figure 1, l'épure d'une monture d'antenne de type azimut-élévation, dans le cas d'un antenne à source excentrée,
• la figure 2, une vue latérale d'une antenne conforme à la figure 1, incluant un support d'antenne conforme à l'invention,
• les figures 3 et 4, deux vues représentant, en élévation et de dessus, le support d'antenne de la figure 2,
• les figures 5, 6 et 7, respectivement, une vue en élévation, une vue en coupe du demi-collier supérieur selon la ligne B-B de la figure 5 et une vue en deux demi-coupes selon les lignes C-C et D-D de la figure 5, illustrant de façon détaillée le support d'antenne des figures 3 et 4.

The various objects and characteristics of the invention will now be described in more detail in the following description of an example of embodiment of the invention, made with reference to the appended figures which represent:

• FIG. 1, the sketch of an antenna mount of azimuth-elevation type, in the case of an antenna with eccentric source,
• FIG. 2, a side view of an antenna according to FIG. 1, including an antenna support according to the invention,
• FIGS. 3 and 4, two views showing, in elevation and from above, the antenna support of FIG. 2,
• Figures 5, 6 and 7, respectively, an elevational view, a sectional view of the upper half-collar along the line BB in Figure 5 and a view in two half-sections along the lines CC and DD of Figure 5 , illustrating in detail the antenna support of FIGS. 3 and 4.

We will first describe, referring to Figure 1 the sketch of an azimuth-elevation type antenna, in the case of an antenna with eccentric source.

The antenna proper comprises a source 1 illuminating an auxiliary reflector 2, which illuminates a main reflector 3. The curvature and the dimensions of the reflection surfaces 4 and 5 are such that, as far as possible, the auxiliary reflector 2 receives all of the radiation 6-6 ′ coming from the source 1 and distributes it in a uniform radiation 7-7 ′ over the entire surface of the main reflector 3, which generates a parallel beam 8-8 ′ having the best polarization characteristics.

The axis 9 of radiation of the antenna is fixed relative to these elements whose relative positions, for a given antenna are also fixed. Pointing the antenna therefore amounts to moving a unitary structure comprising the two reflectors and the source, thanks to an antenna mount.

Figure 1 illustrates an antenna mount of the type azimuth-elevation. This comprises a vertical base 10 on which is mounted an antenna support 11 which, by means of an elevation articulation 12, carries the antenna structure symbolized at 13.

The antenna support 11 is mounted on the base 10 so as to be able to pivot relative to the vertical axis of the base. The antenna can thus rotate in a horizontal plane, within certain limits at least. It is thus pointed in the appropriate direction. In the absence of precise geographic or magnetic references, this score generally needs to be adjusted on site.

The antenna structure 13 is mounted on the antenna support 11 by means of an articulation 12 allowing rotation on a horizontal axis. The antenna can thus be pointed at the desired elevation. This is generally known with precision, when the antenna must be pointed at a specific traffic satellite.

The base 10 can be extended in a rectilinear manner by a leg 14 resting on a horizontal support 15. It can also be extended by a substantially horizontal leg 16 fixed to a vertical support 17. The junction of the base 10 with the leg 16 can be carried out by a double flange 18 at 45 °. The base 10 is thus fixed to any available support so that its axis is strictly vertical.

Once the angle of elevation of the antenna has been adjusted, as we have seen, the antenna support must allow the rotation of the antenna in azimuth, then its blocking in the chosen azimuth, without the elevation be changed. An antenna support designed in accordance with the invention, so that this result can be achieved, will now be described with reference first to FIG. 2.

The antenna shown in Figure 2 conforms to the diagram of Figure 1 and there are the same elements with the same references.

Source 1 is carried by an assembly comprising two legs 20 at the lowest part of the main reflector 3 and two legs 21 also apart. At the ends of the legs 20 is fixed the auxiliary reflector 2, in the appropriate orientation.

The surface 5 of the main reflector 3 is carried by a trellis, not shown, to which the structure 13 is fixed. The antenna structure 13, itself composed of a kind of reinforcement, is supported at four points on the trellis carrying the reflector 3. This structure is carried by the antenna support, to which it is fixed at three points: it pivots at two points forming an elevation articulation 12 and, at another articulation point 22, it is connected by a tie 23 to an attachment 24 of the antenna support 11. The tie 23 is of adjustable length and defines by its length the elevation angle of the antenna.

Figures 3 and 4 show in more detail the composition of the antenna support of the invention. That includes two assembled parts, a cap 30 and a barrel 31. The cap 30, shown in partial section in FIG. 3 and seen from above in FIG. 4, fits onto the barrel 31 to which it is fixed by screws, in 32 for example. This cap 30, a sort of mounting plate, carries the fastener 24, a single pierced tab which for example comes over a stirrup ending the tie rod 23. It is extended by two horns 33, 34 respectively terminated by a conical bearing 35, 36, allowing to take up the clearances and serving as a pivot for articulation 12.

The barrel 31, comprises a sole 40, on which the cap 30 is fixed, an upper half-collar 41, embracing the base 10 and whose arms 46 extend towards the antenna, and an upper flange 42 attaching to the upper half-collar 41 to block it on the base 10, a lower half-collar 43, embracing the base 10 and whose arms 47 extend in the opposite direction to the antenna, and a lower flange 44 attaching to the lower half-collar 43 to block it on the base 10, as well as two lateral uprights 45 extending over a certain distance parallel to the axis of the base and joining respectively the end part of an arm 46 of the upper half-collar 41 to the end part of an arm 47 located below the preceding part of the lower half-collar 43.

The flange 42 is fixed to the half-collar 41 by means of vis-à-vis ears which these two parts comprise and which are joined together, for example by bolting. The geometry of the two parts is such that the assembly can enclose the base 10. The bolts are loose, the assembly is not opposed to rotation.

The flange 44 and the half-collar 43 are arranged in the same way.

As shown in Figure 3, the antenna support covers the upper end of the base 10. The load is on the side of the joint 12. It pulls the half-collar 41 towards the surface of the base 10 On this fulcrum, it pushes the half-collar 43 towards the opposite surface of the base 10. Whether the flanges are tight or not, this defines the position of the antenna support and therefore the angle of elevation of the antenna.

As will be seen below, the uprights 45 are not in contact with the base and do not intervene in the above.

Figures 5, 6, 7 illustrates the antenna support of Figures 2, 3, 4 in more detail, excluding the flanges. The same parts have the same references. FIG. 5 indicates where the planes of the sections of FIGS. 6 and 7 are located. Incidentally, it can be seen that the sole 40 comprises cells 48, for lightening the part. The half-collar 43 also carries a rib 49 serving as a fulcrum for the azimuth rotation of the antenna.

As can be seen by comparing Figures 6 and 7, the half-collars 41 and 43 are rotated in opposite directions. In FIG. 6, corresponding to the section along line BB, the half-collar 41 is a part of semi-circular shape embracing the base 10 over 180 ° at most and whose arms 46 are extended by ears 50 supported by at least one reinforcing veil 51. These ears are pierced at 52 for the passage of the already mentioned tightening bolt. The flange 42 not shown is conventionally a bridge coming to bear on the base 10 in the center of its free part between the arms of the half-collar and which ends on either side by ears appearing opposite and at distance from the ears 50. The elasticity of the flange allows a gradual tightening of the half-collar on the base. FIG. 6 also shows the cylindrical bearing surfaces 53 by means of which the half-collar 41 rests on the base 10. These bearing surfaces are internal projections of reduced angular width, 30 ° for example, of a limited height, less than that of the half-collar, for example, and the cylindrical surface of which can be machined after molding, in order to improve the surface condition and the dimensional accuracy. Advantageously, two bearing surfaces are provided symmetrically arranged with respect to the direction opposite to the antenna, spaced apart for example by 60 °.

The lower half of FIG. 7, corresponding to the section DD shows that, although this is not necessary, the half-collar 43 is similar in all respects to that of FIG. 6, the ears 54, veil 55, worn 56 being counterparts of parts 50, 51, 53 already described.

The upper half of this same figure 7 is a section along the line CC, just above the half-collar 43. We therefore see one of the two uprights 45, at its base, at the end of one of the arms 47 , and we see that it is spread of the base 10, so that it does not intervene in the position that the antenna support can take relative to this base. Thus, the position of the support is only defined by the bearing surfaces 53, 56 which are supported on the base. The rigidity of the uprights 45 combined with the precision of the bearing surfaces makes it possible to precisely define the antenna elevation and to guarantee it permanently, whether the antenna support is free to rotate or, on the contrary, freed by the loosening of the flanges. To this end, the antenna support will advantageously be produced in the form of a single molded part of which, as indicated, only the cylindrical surfaces of the surfaces will be machined.

It is obvious that the foregoing description has been given only by way of nonlimiting example and that numerous variants can be envisaged, without however departing from the scope of the invention.

Claims (5)

1. An azimuth-elevation type antenna support comprising a stock and a mounting plate on which the antenna is fixed, said support being mounted on a base relative to which the antenna takes up a cantilevered position, the support being characterized in that said stock (31) comprises essentially, in a single metal part: at least one top half-collar (41) disposed around the base (10) and having its arms (46) extending towards the antenna, with a top strap (42) fixed to the top half-collar (41) in order to lock it on the base; a bottom half-collar (43) disposed around the base and having its arms (47) extending away from the antenna, with a bottom strap (44) fixed to the bottom half-collar (43) in order to lock it on the base; and two side risers (45) extending over a certain distance parallel to the axis of the base and each interconnecting the end portion of one of the arms (46) of the top half-collar (41) to the end portion of the bottom half-collar (43) located therebelow.
2. An antenna support according to claim 1, characterized in that each of the half-collars is disposed around about 180° of the base.
3. An antenna support according to claim 1, characterized in that each of the half-collars includes at least one internal cylindrical bearing surface of height and of angular extent which are less than those of the half-collar.
4. An antenna support according to claim 3, characterized in that each of the half-collars includes two cylindrical bearing surfaces symmetrically disposed relative to its arms and at an angular spacing of about 90°.
5. An antenna support according to claim 3, characterized in that the antenna support is constituted, apart from the two straps, essentially by a metal casting, and in that only said bearing surfaces in the half-collars are machined.

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