Portable parabolic reflector for microwave energy

BACKGROUND OF THE INVENTION

The present invention relates in general to parabolic reflectors and more particularly concerns a sectionalized parabolic reflector of microwave energy where portability is a prime consideration.

In typical mobile and fixed microwave communications stations, it is important to transport the antenna systems to the site of operation using a minimum of storage volume and weight to keep shipping costs low and facilitate transport with a wide variety of transportation media.

Typically the communication industry uses antenna systems having parabolic reflectors manufactured in one piece. These reflectors usually have a circular aperture. Not only are these reflectors expensive to transport, especially in sizes larger than six feet in diameter, but handling is difficult and transport media limited to those capable of handling such large packages. Usually such reflectors are made by spinning a soft aluminum material, such as 1100-0. This forming process has a number of limitations, one of which is the requirement that the reflector surface thickness be at least Vs, thereby limiting lightweight design capability.

Accordingly, it is an important object of this invention to provide a compactly transportable lightweight sturdy parabolic reflector.

It is another object of the invention to achieve the preceding object with a parabolic reflector having an aperture shape that facilitates minimum storage volume.

It is another object of the invention to achieve one or more of the preceding objects formed of pieces of uniform aperture shape when the reflector is disassembled.

Another important object of the invention is to provide a relatively small reflector aperture to reduce wind loading on the reflector support structure.

It is still a further object of the invention to achieve one or more of the preceding objects while providing a parabolic reflector that exhibits good electrical performance.

SUMMARY OF THE INVENTION

According to the invention, the reflector sections are joined together by means including a series of male and female portions coacting with alignment pin means and locked in place by means including spring-loaded balls. According to another aspect of the invention the reflector sections are supported by welded tubular A-frames at25 tached to the reflector in the same manner as the reflector sections are attached to one another.

Numerous other features, objects and advantages of the invention will become apparent from the following specification when read in connection with the accompanying drawing in which:

BRIEF DESCRIPTION OF THE DRAWING

FIGS. 1 and 2 are back and side views, respectively, of an embodiment of the invention; and

FIG. 3 is a perspective view of interconnecting means according to the invention comprising male and female castings in conjunction with an alignment pin locked in place by spring-loaded balls.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

With reference now to the drawing, and more particularly FIGS. 1 and 2 thereof, there are shown back and side views, respectively, of an embodiment of the invention. As seen in FIG. 1, the reflector according to the invention is made up of four similar sections forming a cross. There is an upper section 11, a lower section 12, a left section 13 and a right section 14. Upper section 11 is formed with a number of depending female castings 15, 16, 17 and 18 that mate with male castings 21, 22, 23 and 24. Male castings 21 and 22 extend from left section 13 while male castings 23 and 24 extend from the top of right section 14. Left section 13 and right section 14 are joined together by similar castings, such as female casting 25 on right section 14 and male casting 26 on left section 13. Similarly lower section 12 is formed with male castings such as 31 and 32 that mate with female castings such as 33 depending from left section 13 and 34 depending from right section 14.

An upper support member 35 carries the A-frames 41, 42, 43 and 44 that keep reflectors 11, 12, 13 and 14 in position. Each of these A-frames is formed with three male aluminum castings at each end, such as 45, 46 and 47 at each end of A-frame 41. Two of these male castings, such as 46 and 47 mate with a corresponding female casting such as 51 and 52 in a hinged support 50 that is carried by support member 35. FIG. 2 shows a view of how projection 52 is formed on a support member having an upper hinge portion 53 that rides on a lower hinged portion 54 on franie 35 and aligned therewith by a vertical hinge pin 55 to perinit azimuth alignment of the reflector. The other male casting, such as casting 45, is seated within a female casting, such as 56 at the point of a pyramid defined by four support rods, such as 57, 58, 60 and 61 extending from the corners of a reflector section such as upper section 11.

Upper support member 35 is carried by a pedestal 71 on a left hinge 72 and a right hinge 73. An azimuth turnbuckle 74 adjusts support frame 50 about the upper hinge portion 53 and lower hinge portion 54 to permit orientation of the reflector assembly in azimuth. Elevation turnbuckle 75 adjusts the pitch of upper support member 35 about left hinge portion 72 and right hinge portion 73 to permit adjustment of the assembly in elevation.

The reflector assembly is illuminated by a horn 81 supported by upper and lower supports 82 and 83 having its center of radiation substantially at the reflector focal point and fed by a waveguide assembly 84 that also functions to provide support for horn 81. A waveguide coupling assembly 85 couples waveguide 84 to the waveguide sections 86 that may be connected to an associated transmitting and/or receiving system.

Referring to FIG. 3· there is shown a perspective view of the interconnecting means according to the invention comprising male and female castings in conjunction with an alignment pin locked in place by spring loaded balls.

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Female casting 100 comprises a base plate 101 formed with fastening holes, such as 102, and a pair of perpendicularly extending end blades 103 and 104 defining a slot 105 for receiving an intermediate blade 106 extending perpendicularly from base plate 107 of male casting 108. Base plate 107 is formed with fastening holes, such as 112. Blades 103,104 and 106 are each formed with a hole for snugly accommodating alignment and locking pin 113.

Pin 113 has a head 114 with an eyelet 115. The other end 116 of pin 113 is tapered and carries a pair of springloaded balls 117 and 118. Eyelet 115 may receive one end of a string, the other end of which is tied to a point near the casting to help prevent losing pins and insuring their convenient availability during assembly.

Assembly is quick and simple. The intermediate blade 106 is inserted in slot 105 with the holes in blades 103, 104 and 106 in alignment about a common axis. Then pin 113 is pushed through the three aligned holes until spring loaded balls 117 and 118 pop out after clearing the hole in end blade 103. Disassembly is equally quick and simple. Pin 113 is removed, and blade 106 removed from slot 105.

There has been described a novel transportable reflector support structure characterized by transportability, ruggedness, high electrical performance· ease of assembly and disassembly, ease of fabrication, disassembly into compact components compactly storable for ease and economy in transportation and ease of directional adjustment. It is evident that those skilled in the art may now make numerous modifications and uses of and departures from the specific embodiment described herein without departing from the inventive concepts. Consequently, the invention is to be construed as embracing each and every novel feature and novel combination of features present in or possessed by the apparatus and techniques herein disclosed and limited solely by the spirit and scope of the appended claims.