GB2232008A - Mountings for telecommunications dishes - Google Patents

Abstract

A dish mounting for use in a selected latitude includes a base 12 for attachment to a supporting structure and a frame 13 pivotally mounted on the base 12. The dish 10 is arranged for pivotal movement relative to the frame 13 about a fixed pivot axis B which is inclined to the horizontal at an angle which is equal, within 1 DEG , to the angle of latitude of the location at which the dish 10 is to be installed. The frame 13 includes a horizontal member 28 which may carry a compass and a spirit level 33 to assist in accurate installation of the dish 10 in a South-facing orientation. <IMAGE>

Description

MOUNTINGS FOR TELECOMMUNICATIONS DISHES Field of the Invention.

This invention re]ates to mountings for use in the attachment of telecommunications dishes to supporting structures, such as walls and chimneys. One form of such mounting is shown 1.. European Patent Specification No.008788.

Background to the invention There is now a considerable increase in the use of telecommunications dishes, which are normally mounted on the roof or on an outside wall of the house or other buildinc within which tr;e television receiver is located. With the planned @@@ther increase in the number of satellites from which television programmes can be received, there is a need for a simple, cost-effective method of mounting such a dish.

Summary of the Invention According to a first aspect of the present invention there is provided a mounting for a telecommunications dish to be used in a selected latitude, which mounting includes a base on which a frame is pivotally mounted for movement relative thereto about an axis which, in use, is disposed vertically, the means providing for such pivotal movement permitting the frame to be swung about said axis and then clamped in position in which a horizontal member of the frame is directed due South, the frame providing a pair of spaced pivot points for the mounting of a holder for the dish, the two spaced pivot points defining a pivot axis fixed in relation to said horizontal member and inclined thereto at an angle equal to the angle of the selected latitude, and means whereby the dish can be turned about said pivot axis and held in a selected position.

Thus, for a dish to be useo at a latitude of 51 degrees North, the pivot axis will be inclined at an angle of 51 degrees to the horizontal member. For a given satellite, the satellite "footprint" will affect the accuracy with which the angle between the pivot axis and the horizontal must approac:r.

the angle of the selected latitude. The efficiency of the dish also needs to be taken into account. It is preferred that the angle between the fixed pivot axis and the horizontal member should be within 1 degree of the angle of the given latitude.

In order to facilitate installation of the dish, a level indicator may be provided, for example, a spirit 3eve3 may be carried by the horizontal member to provide a clear visual indication that said member has actually been installed in the required horizontal attitude. A compass may also be provided, either on the base or on the frame, to provide a visual indication that the horizontal member is directed due South.

The means whereby the dish can be turned about the fixed pivot axis may comprise a motor which is remotely controlled to direct the dish towards a selected satellite. Alternatively, a manually operable adjustment facility may be provided.

According to a second aspect of the present invention there is provided a method of mounting a telecommunications dish on a supporting structure located in a selected latitude, which method comprises providing a base on which a frame is pivotally mounted for movement relative thereto about vertical axis, the frame including a horizontal member and a pair of spaced pivot points for the mounting of a holder for the dish, which spaced pivot points define a pivot axis fixed in relation to said horizontal member and inclined thereto at an angle which is equal to the angle of the selected latitude, the method comprising:: a) attaching the base to the supporting structure in such manner as to ensure that the pivot axis between the base and the frame is vertical and the horizontal member is disposed horizontally, b) swinging the frame relative to the base into a position in which the horizontal member is directed due South, and c) clamping the frame against movement relative to the frame when in this South-facing location, means being provided whereby the dish can be turned about the fixed pivot axis defined by the pair of spaced pivot points.

Brief Description of the Drawinqs Figure 1 is a side view of a satellite dish mounted on chimney, and Figure 2 is side view, to a slightly increased scale, of the mounting and dish, but excluding the LNB.

Description of the Preferred Embodiment The drawings show a mounting for a prime-focus satellite tracking dish 10 which is intended to be attached to a chimney 11, the mounting comprising a base 12 and a frame 13 pivotally mounted on the base 12 for movement relative thereto about a vertical pivot axis A.

The dish 10 is arranged for pivotal movement relative to the frame 13 about a pivot axis B which is affoRded by a pair of spaced fixing points 14 and 15. Axis B is inclined to the horizontal at an angle which is equal, within 1 degree, to the angle of latitude of the location at which the dish is to be installed. Assuming, for example, that the axis B is inclined at an angle of 51 degrees to the horizontal, then the dish can be mounted at locations between 50 degrees North and 52 degrees North.

As shown in the drawings, the dish 10 is arranged for rotation about axis B, to enable it to track a satellite, by means of a manual actuator 16. Tracking can alternatively be effected by remotely controlled motorised actuator.

The base 12 includes two portions 15 and 18 which are inclined at right ang3es to one another. Each portion 15,18 includes upper and lower horizontal box-section elements 17A, lIB, 18A and 18B respectively, the upper and lower elements of each portion being connected by a metal strut 19,20. The two portions 15 and 18 are connected together by nut and bolt mechanisms 21 which can be thightened so as to lock the two portions together in the required position of adjustment.

The elements 1A, 17B, 18A and 18B terminate in end formations which enable the mounting to be lashed in position on the chimney 11. The elements liA, 1/B, 18A and 18B are formed with elongated slots 23 and the vertical struts 19 anc 20 are formed with apertures 24. The slots 23 and apertures 24 serve to receive fixing screws for attachment of the base 12 to the chimney stack 11 in such manner that the junction between the two portions 17 and 18 is at a corner of the chimney stack. It will be appreciated that, for mounting a dish on the side wall of a house, a similar arrangement including metal box-section elements can be used.

The horizontal elements 18A and 18B of portion 18 each carry a mounting plate which is welded to the associated element 18A or 18B, the two mounting plates 25 being dried so that each has a generally central aperture and the two apertures being disposed in register to define pivot axis A.

Releasable clamping means 26 and 25 in the form of bolts and locknuts pass through these apertures. The provision of the releasable clamping means enables the frame 13 to be swung about axis A and then lock the frame 13 in the required adjusted position. As shown, the available arc of swing is almost 2,0 degrees and the dish 10 can accordingly always be moved into a position facing due South.

The frame 13 consists of box-section steel tube 28, a vertical steel strip 29 and an inclined steel strip 30.

The lower fixing point 15 is carried by an upturned end portion 34 of element 28 and the upper fixing point 14 is carried by strip 30 which extents generally parallel to the pivot axis B. The dish 10 is attached to â holder in the form of a carrier ring 55 which is attached by upper and lowe! struts S and 38 to the upper and lower fixing points 14 anc 15, the carrier ring 35 including a generally circu3ar frame with spaced apart attachment Jugs to which the dish 10 is secured.

The manual actuator 16 extends between the tube 28 and one of the lugs on the carrier ring 35. The actuator 16 incudes a rod 9 which is of uniform cross-section and is threaded throughout its length. A joint 40 is provided at one end of the rod 39 for connection to the lug on the carrier ring 35. The joint 40 includes a threaded stub shaft, a yoke and a sleeve which fits over the threaded rod 39 and is held in position on the rod 39 by a pair of Zocknuts 41. The yoke is free to pivot relative to the sleeve about the axis of a trunnion interconnecting the yoke and the sleeve.The stub shaft is connected to the lug on the carrier ring 35 and is fixed in position by means of a locknut 42 so that a positive but pivotal connection is provided between the actuator 16 and the carrier ring 35 at a position spaced from the upper and lower fixing points 14 and 15.

An axially displaceable sleeve 43 is positioned on the threaded rod 9 and is located between a pair of nuts 44 and 45 which can be used as stop members. A further nut 46 is fixed to the free end of the threaded rod 39. This fixed nut 46 can be engaged by a suitable tool to effect rotation of the rod 9 to cause axial displacement of the sleeve 43 along the length of the rod 39 as a result of the threaded engagement between the thread on the rod 39 and an internal thread of the sleeve 4 . The sleeve of the joint 40 has an unthreaded bore and thus does not move axially of the rod 39, being held in position axially of the rod 9 between the two locknuts 41.

The sleeve 4 is connected by a universal joint to a stub shaft 45 which passes through aligned bores in the box section element 28 and is fixed against movement relative to the element 28 by means of a locknut 48 tightened onto a threaded end portion of the stub shaft 45.

Rotation of the rod 39 by means of the fixed nut 46 will cause a variation in the spacing between the sleeve 43 and the sleeve of the joint 40 and hence a variation in the spacing between the sleeve 43 and the carrier ring 35. The variable length arm afforded by the rod 39 will thus serve to support the carrier ring 35 and the dish 10 in the orientation to which they have been moved. Fine adjustment of this orientation can be effected by rotating the nut 46.

If the dish is to be directed towards a single satellite and it is accordingly required that the dish 10 should be held in a fixed position, the two nuts 44 and 45 will be rotated along the length of the rod 39 so as to bear against the sleeve 43 and thus hold the sleeve 4 positively against movement axially of the rod 39. If, however, it is intended that the dish 10 should be capable of movement from a position directed towards one satellite into a position directed towards another satellite, the two nuts 44 and 45 can be used as stops with the sleeve 43 bearing against one stop when the dish 10 is directed towards one satellite and located against the other stop when the dish is directed towards the other satellite.

In order to avoid the application of excessive stresses to the chimney 11, angle-section elements 49 are placed in position at three corners of the chimney 11 with the junction between the two portions 17 and 18 of the base 12 located at the other corner of the chimney 11, the base 12 being so positioned that the frame 13 projects from that face of the chimney 11 which is closes to due South. Two cords 50 extend around the chimney 11.

The dish 10 shown in the drawings is a prime-focus dish having an LNB 51 located at the focus of the dish 10 with the LNB 51 carried by the dish on support arms 52. There will, however, be occasions when it is more appropriate to use an offset dish configuration and the dish holder will then be modified according3y.

In order to ensure that the axes A and B are disposed correct3y, the box section element 28 carries spirit level and, on installation, any necessary packing wi33 be inserted behind the angle-section elements 49 to bring the element 26 unto an accurately established horizontal position. The element 28 may also carry a compass (not shown) to assist in ensuring that the dish 10 faces due South.

In the particular arrangement shown in the drawings, the mounting includes a base intended to be attached to a supporting structure such as a wall or chimney. However, the base 12 may be replaced by a vertical pole and the chassis 13 has upper and lower eye-bolts which are mounted on the pole.

With such an arrangement, the chassis 13 is postioned on the pole and is clamped in position with the eement 28 disposed horizontally and facing due South. Installation of the dish is thus greatly facilitated as compared to existing pole mounting systems.

Claims (7)

Claims:

1. A mounting for a telecommunications dish to be used in a selected latitude, which mounting includes a base on which a frame is pivotally mounted for movement relative thereto about an axis which, in use, is disposed vertically, the means providing for such pivotal movement permitting the frame to be swung about said axis and then clamped in a position in which a horizontal member of the frame is directed due South, the frame providing a pair of spaced pivot points for the mounting of a holder for the dish, the two spaced pivot points defining an axis fixed in relation to said horizontal member and inclined thereto at an angle equal to the angle of the selected latitude, and means whereby the dish can be turned about said pivot axis and held in a selected position.

2. A mounting according to Claim 1, in which a level indicator is carried by the horizontal member.

3. A mounting according to either of the preceding claims, in which a compass is provided, either on the base or on the frame, to provide a visual indication that the horizontal member is directed due South.

4. A mounting according to any one of the preceding claims, in which the means whereby the dish can be turned about its pivot axis comprises a remotely controlled electric motor.

5. A method of mounting a telecommunications dish on a supporting structure located in a selected latitude, which method comprises providing a base on which a frame is pivotally mounted for movement relative thereto about a vertical axis, the frame including a horizontal member and a pair of spaced pivot points for the mounting of a holder for the dish, which spaced pivot points define a pivot axis fixed in relation to said horizontal member and inclined thereto at an angle which is equal to the angle of the selected latitude, the method comprising: - a) attaching the base to the supporting structure in such manner as to ensure that the pivot axis between the base and the frame is vertical and the horizontal member is disposed horizontally, b) swinging the frame relative to the base into a position in which the horizontal member is directed due South, and c) clamping the frame against movement relative to the base when in this South-facing location, means being provided whereby the dish can be turned about the fixed pivot axis defined by the pair of spaced pivot points.

6. A mounting for a telecommunications dish substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

7. A method of mounting a telecommunications dish on a supporting structure substantially as hereinbefore described with reference to and as shown in the accompanying drawings.