US2445329A - Mast antenna - Google Patents

Description

July 20, 1948 R. E. KESTER Er AL 2,445,329

MAST ANTENNA 2 Sheets-Shea?I 1 Filed March 25, 1944 Flsa/ 'B INVENTOR.

yROBERT E. KEsTER WILLIAM s. Qumcm /Q-Z@ @4f/Mx ATTORNEY July 20, 1948. R. E. KESTER Er AL 2,445,329

MAST ANTENNA oBERT E. KESTER ATTORNEY WILLIAM S.QUINCY,JI?`

Patented July 20, 1948 MAST ANTENNA Robert E. Kester and William S. Quincy, Jr.,

Dayton, Ohio Application March 25, 1944, Serial No. 528,056

(Cl. Z50-33) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

` This invention relates to mast antennas and more particularly to a mast antenna for use on aircraft and the like.

'The objects of the present invention include the provision of a properly functioning, rugged and durable mast antenna that comprises a minimum number of securely joined parts that are adapted for simple and rapid manufacture and assembly; a mast antenna that is sufficiently reinforced to withstand prolonged exposure to vibration and the like, and to provide a long period of service.

With the above and other objects in view which will be apparent to those who are informed in the iield of development in which the present invention belongs, an illustrative embodiment of the Apresent invention is presented in the accompanying drawings, wherein:

Fig. 1 is a fragmentary foreshortened side elevation of a mast antenna that embodies the present invention;

Fig. 2 is a fragmentary foreshortened edge elevation view of the mast antenna that is shown in Fig. 1;V

Fig. 3 is a plan view of the Contact carrying connecting plate mounted on the base of the mast antenna that is shown in Fig. 1;

Fig. 4 is a section taken along the line 4-4 in Fig. 1;

Fig. 5 is an enlarged side elevation of a current carrying assembly for mounting within an axially extending aperture in the base of the mast antenna that is shown in Fig. 1; and

Fig. 6 is a diminished side elevation of the plated stai of the mast antenna that is shown in Fig. 1.

The mast antenna that is shown in the accompanying drawings comprises a tapered and streamlined mast staff I, that extends continuously throughout the length of the antenna and that preferably is made of compressed phenolic impregnated plywood, although it may be of plastic or other composition and solid or hollow, as preferred. The phenolic impregnated plywood of which the mast staff I is made, preferably is compressed so that its specic gravity is graduated from a maximum value at the zone of maximum stress of the mast antenna to a minimum value at its tip. A mast antenna that embodied the present invention was found to have a specie gravity of 1.2 at its zione of maximum stress decreasing gradually to a specific gravity of 0.9`

at its tip. j The mast staff I is surfaced in any desired manner with a tightly joined skin or sheath 2 that encloses the tip end of the staff I and that extends continuously longitudinally of the -mast staff for a distance that preferably is substantially a fraction of, or a multiple of the wavelength of, the electrical impulses that it is to conduct. The metal skin or sheath 2 is preferably firmly bonded to or closely fit upon the surface of the mast staff I as by being electroplated, metal sprayed, or otherwise deposited thereon or secured thereto. When it is desirable to have a wire attached to the tip of the mast antenna, a grommet or brass tube 3, that is secured in place by being flared at both ends, as shown, or the like, is disposed within a Wire receiving aperture adjacent the tip of the mast stai I and makes continuous electrical contact with the metal sheath 2.

The base of the mast staff I is drilled longitudinally to receive a suitable conducting cable assembly that comprises an inner cable 4 that is connected electrically at one end to the metal sheath 2 in any suitable manner, as thru the slug 5 that is soldered to the cable 4 and is tapped to receive the threaded tip of a screw 6 that is in contact with the sheath 2, or the like. The screw 6 extends transversely of the mast staff I along the longer dimension thereof and its head portion is in electrical connection with the metal sheath 2. as by being soldered thereto, mounted in place during the deposition of the sheath 2, or the like. The opposite end of the inner cable 4 makes electrical connection with a central contact 1 that preferably comprises an axially split conical hollow sleeve opening outwardly of the assembly or of other desired type of contact. The inner cable 4 is preferably disposed Within an insulating tube 3, outwardly of which is disposed a woven copper hollow cable 9 that has a slug I0 soldered to its inner end. The slug I0 is tapped for the reception of the inner end of a screw II that extends to the outside of the mast stati' and that is provided at its exposed end with suitable means, such as a pair of nuts I2, or the like, for securing a ground connection (not shown) to the screw II so that when the antenna is installed the screw II may be grounded to the skin of an airplane upon which the mast antenna is mounted or to other electrically grounded part.

The outer end of the woven hollow cable 9 makes electrical connection with a tubular part I3 of a plate I4, as by being soldered thereto or the like. The rim of the plate I4 faces against a plate I5 of substantially the same peripheral dimensions. Both the rim of the plate I4 and the plate I5 are apertured for the disposition of screws I 6 or the like therein for securing the plate rim I 4. and the plate I5 upon. the ilat face of the base of the mast staff I. The plate I5 is integral with a cylindrical ground connection I'I that is concentric with and insulated from the` central contact 'I. The cylindrical ground connection II terminates at its free end in a plurality of teeth I8. Another outer insulating tube I9 is disposed outwardly of the woven hollow cable. 9.

The center of gravity of the mast antenna preferably is positioned substantially as indicated by the intersection 20 in Fig. 6. Supporting clamps 2I for stabilizing the mast antenna in its mounted position are indicated in dottedk outline in Fig. 6 of the drawings.

It will be understood that the details of construction that have been. shown and described. herein. have been submitted for the purposes of illustrating and describing an embodiment of the present invention and that modifications and refinemente may be made therein Without departr ing from. the invention as. defined by the appended claims.

What we claim is:

1. A mast antenna, comprising in combination a mast sta-fi of phenolic impregnated plywood compressed to a maximum density at substan tially the zone of greatest stress thereof, an el-ectri-cally conducting sheath overlying and supported by a portion of the outer surface oi said mast staff, av cable assembly disposed Within an apcr ture extending longitudinally of said mast staff and opening outwardly through the base portion thereof, an inner cable part of said cable assembly extending substantially longitudinally thereof, a tapped and threaded rst slug soldered to said inner cable at substantially an inner end thereof, a central contact accessible from outwardly of said mast antenna and disposed at an outer end of said inner cable, a iirst screw in electrical connection. with said sheath and threaded into said rst slug', a woven hollow cable insulated from and substantially' coaxial with. said inner cable and extending longitudinally thereof, a cylindrical insulating tube extending longitudinally of both said inner cable and said Woven hollow cable and interposed therebetween, a second tapped and threaded slug soldered to said Woven hollow cable at substantially an inner end thereof, a second screw having one end threaded into said second slug and having an opposite end extending to the outside of said mast staff, a ground connection at an outer end of said woven hollow cable and accessible from outwardly of said mast antenna, and means insulating said central contact from said ground connection.

2. An antenna for radiating electrical energy, comprising in combination a staff of electrically insulating material, a base portion of said staff through which an aperture that extends longitudinally of saidv antenna opens, an electrically conducting sheath bonded closely throughout its inner surface to said staff upwardly from the base portion thereof, an electrically conductive terminal assembly disposed within the aperture in said antenna, a central connection portion of sai-d terminal assembly accessible from outwardly of the base portion of said staff, a ground connection portion of said terminal assembly accassible from outwardly of the base portion of said stai and insulated from said central connection portion of said terminal assembly, means connecting said central connection tol said sheath. and ground connection connecting means insulated from said central connection sheathconnecting means and accessible from outwardly of said staff base portion.

ROBERT E. KESTER. WM. S. QUINCY, JR.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATE PATENTS Number Name Date 1,962,227 Zepler June 12, 1934 1,976,804 Ringel Oct. 16, 1934 2,251,708 Hefele Aug. 5, 1941 ,2,266,139 Zukerman Dec. 16, 1941 FOREIGN PATENTS Number Country Date 548,244 Great Britain Oct. 2, 1942 502,460 Great Britain Mar. 17, 1939

Images