US2351723A

US2351723A - Fin mast antenna

Info

Publication number: US2351723A
Application number: US487996A
Authority: US
Inventors: Arthur G Vogel
Original assignee: REMPE Co
Current assignee: REMPE Co
Priority date: 1943-05-22
Filing date: 1943-05-22
Publication date: 1944-06-20
Anticipated expiration: 1961-06-20

Description

June 20, 1944. vo 2,351,723

FIN MAST ANTENNA Filed May 22, 1943 Patented June 20, 1944 FIN MAST ANTENNA Arthur G. Vogel, Chicago, Ill., assignor to Rempe Company, Chicago, 111., a. corporation of Illinois Application May 22, 1943, Serial No. 487,996

1 Claim.

My invention relates to mast antennas for radio reception. Its object is to improve radio reception, especially with the type of mast antenna which is directionally adjustable. The improvement in reception is achieved by my invention without increasing the length of the mast antenna and without increasing the transverse dimensions thereof to an extent appreciably to complicate packaging it, or to interfere with its juxtaposing a wall which it may parallel.

Also, by my invention I may laterally extend the surface as a multiplicity of surfaces in condenser-like relationship and at normals to the axis of the mast, which extended surface is rather compactly arranged about the mast and rigidly fixed thereon and supported thereby.

My invention also concerns an improved insulated mounting and adjustable bracketing of the antenna mast.

The foregoing, together with further objects, features, and advantages of my invention, are set forth in the following description of a specific embodiment thereof as illustrated in the accompanying drawing wherein:

Fig. 1 is a perspective view of the fin mast antenna of my invention mounted on a window frame; and

Fig. 2 is a longitudinal vertical section thereof.

My fin mast antenna II), as a whole, is shown as mounted on the exterior frame I I of a window and preferably swung and inclined somewhat upwardly of a direction toward the transmitting station from which reception is most sought. The backbone or mast proper of my antenna is a tube I2 of high conductivity metal preferably of uniform external diameter. Upon this tube are rigidly mounted, at spaced intervals, a multiplicity of fins I3. While these fins may be discs, I prefer that they be squares of thin sheet stock of a high conductivity metal such as copper.

Each fin I3 has a central hole l4 whereby the fins can be slipped upon the tube. The central hole I4 of each fin may be margined by a narrow flange I5 making surface contact with the periphery of the tube.

The fins are made fast upon the tube in any well-known manner such as by internal expansion of the tube, by crimping the flange I 5 upon the tube, by making the hold I I such a tight fit that the fins are adequately fixed by friction, by welding, or by a metal bath.

Whatever be the specific technique employed for fixing the fins, they are made sufiiciently fast to preserve them, under ordinary treatment, at normals to the axis of the mast whereby each fin is maintained substantially parallel with its neighboring fins.

I have found that, balancing cost and weight against performance, it is most desirable that the inter-fin spacing be in the order of about half the fin width, and that the fin width be several times the tube diameter.

The upper end of the tube may be closed by a pointed plug I6 preferably of metal.

The lower end of the tube I2 is fitted into the socket Ila of a piece of insulation I1, and is fixed therein as by cementing. The piece of insulation I 7 also preferably embodies a convex dished shield no, the margins of which are undercut to shed water.

The bottom end of the piece of insulation IT is conformed as a threaded stud lie. The socket I7a preferably extends, as shown, well down into the interior of the threaded stud Ilc, whereby the metal tube I2 serves to reinforce the insulation piece at the neck of the stud I'Ic where the piece of insulation would otherwise be most likely to break.

The stud IIc threads into the socket I8 of the ball member I9 of a mast mounting which also includes a complementary or socket member 20 fixed to the window frame or other supporting surface as by wood screws 2|. The ball and socket members I9 and 20, which may be of metal, permit a universal direction adjustment of the mast antenna, which adjustment may be fixed by socket clamping thumb screws 22.

The lead-in conductor 23 may conveniently be connected to the base of the tubes or, as here shown, to the lowermost fin. My fin mast antenna is disposed with its axis in a more or less vertical position and consequently the several fins are in more or less horizontal position and thereby in turn more or less parallel with the ground, tending toward increasing the condenser capacity of the antenna in its radio reception.

By the compactly arranged surface extension at normals to the axis of my antenna its condenser capacity is greatly increased for the improvement of radio reception, without increasing its over-all length and. without substantially increasing the over-all transverse dimensions of the antenna beyond those of the usual shield and mounting.

I claim:

A mast antenna for radio reception comprising a supporting means adapted to be secured to a building or other supporting structure including a pair of metallic members one of which is adapton said plates for mounting said plates in spaced relation directly on said mast comprising an aperture in each plate having a margin defined by a flange, said flange making low impedance surface contact with said mast and means for fixedly mounting said flange on said mast whereby said tubular mast forms the sole support for said plates, said mast and plates constituting the effective antenna, and a lead-in conductor con- 10 nected to said effective antenna.

ARTHUR G. VOGEL.