US 2341401 A
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Description (OCR text may contain errors)
Feb. 8, 1944. v lT 2,341,401
RADIO ANTENNA Filed Aug. 9', 1939 INVENTORY WESLEY J1 WHITE Patented Feb. 8, 1944 RADIO ANTENNA Wesley J. White, Cleveland, Ohio, assignor to The Radial-t Corporation, Cleveland, Ohio, a
corporation of Ohio Application August 9, 1939, Serial No. 289,154
2 Claims. (01. 250-33) i This invention relates to an antenna assembly unit including a telescopicallyextensible aerial and a reel for extending and retracting the aerial.
An antenna of the general nature indicated above involves far more than at first appears. The entire assembly must be designed electrically to meet two conditions. First, the antenna proper, in addition to being an eilicient medium for receiving or sending radio signals must be completely insulated from the metallic vehicle body on which it is normally mounted. .Second, for appearance sake, the aerial when retracted is contained within the body and even in an active position has parts electrically connected to it which are within the body. Such parts of the assembly must be properly shielded to prevent the signals from being interrupted by ignition noises and the like which might be picked up.
In addition to the electrical features outlined above the unit must be very easy to operate which means that the operating parts must not bind or jam. Reel operated antennae normally include a long guided flexible member and this has a tendency to bind in its confining case which aggravates the mechanical problem present.
Further such antenna must be made available in large quantities at a low cost of parts which are inexpensive and easily fabricated.
The chief object of the invention then is the provision of an operating mechanism which will function smoothly and with a minimum of effort and which is not liable to become jammed or locked during use. Still another object has been to provide an electrically efiicient antenna of minimum cost and number of parts.
, To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawing and the following description setting forth in detail certain structure embodying the invention, such disclosed structure constituting, however, but one of various forms in which the principle of the invention may be used.
In said annexed drawing- Fig. 1 is a side elevation partly in section of the signal-carrying antenna employed with my invention;
Fig. 2 is a vertical section through the winding reel mechanism employed;
Figs. 3 and 4 are sections through Fig. 2 as indicated by the lines 3-3 and 4-4 thereon;
Fig. 5 is a side elevation partially in section of a modified form of my invention; and
Fig.6 is a section through Fig. 5.as indicated by the line 6-6 thereon.
Referring now to Fig. 1, the aerial proper comprises a sleeve H) which is bolted as at l2 to the vehicle body and is insulated therefrom to prevent the transmission of the antenna signals to the car body with a consequent grounding thereof. A lead M from the base of the aerial connects with the radio set to transmit the signals between the set and the aerial. The sleeve I0 is necked inwardly as at IE to closely embrace a second sleeve ll slidable therein.
The sleeve I1 is provided with a resilient spring member [8 at its bottom portion which cooperates with the necked-in part IE to retain the sleeves in fixed relation with each other and also to prevent rattling therebetween. The sleeve I1 is necked in at I9 and slidably receives a rod 20, which at its lower end is provided with a resilient spring member 2| similar to the member l8 and for the same purpose. A ball 22 surmounts the rod 20.
In extending the antenna the rod is pushed upwardly by a flexible cable 25, hereafter de scribed, which is soldered as at 26 to the end of the rod.
As the rod 2 is pushed upwardly the member 2| ultimately engages a shoulder 2'! formed by the necked-in part 19 and then pulls the sleeve I! up until its member It comes into abutment with a similar shoulder 28 of the neckedin portion 15 of the sleeve Ill. Electrical contact is maintained between the sleeve and the rod and the lead-in connection I4 to provide a continuous electrical unit.
The cable 25 is normally coiled about a reel 30 (Fig. 2) which is rotated by a hand crank 32. The reel is formed of a molded plastic disk 33 of insulating material, as Bakelite. One flat face of the reel is formed with a helical recess 34 comprising several convolutions extending about the axis of the reel, as indicated in Fig. 2. This recess is adapted to accommodate the cable 25, which is secured at the inner end thereof at 35.
To hold the cable within the recess or passage a cover plate 3'! is provided which lies closely adjacent the recessed face of the reel and prevents the cable from coming out of the recess except at a transverse slot 38 which is of a width suflicient to span all the convolutions oi the recess 34. The cable, which is normally coiled in the reel 33, is guided onto or oil of the reel from a corresponding convolution by the slot 38 as the handle 32 is turned. The cable leads from the reel to the inner end of the rod 20 passing through the antenna sleeves and a sheath. A metallic sheath 40 encloses the cable from the end of the sleeve l until it passes within the reel. The sheath is of metallic construction and is grounded as indicated in Fig. 2. It is electrically separated from the sleeve [0 by the insulating washer M. The interior of the sheath is likewise insulated to prevent electrical contact between it and the cable with a consequent grounding of the antenna. A funnel-shaped metallic cap 42, insulated on the inside, connects the end of the sheath adjacent-the reel and'a metallic grounded container 43 which encloses the 'reel. This container surrounds the reel and cooperates with the sheath to prevent the wire 25 from picking up ignition noises and the like from the car and transmitting them to the set. There "is of course noelectrical contact between the cableand-any part of the sheath or the funnel-like member 42 or the enclosure 43.
A modified form of my invention is shown in Figs.'- and 6. This comprises a cylindricalreel 50iormed of similar material to the reel 33 which is provided with a continuous helical recess 52 extending peripherally of the cylinder and adapted to receive the wire 25. The wire is fastened at 53 into the end of the recess.
To guide the wire into the proper convolution of the recess and retain it therein an enclosing cover 54 formed of a moldedinsulating plastic, as the cover 31, is provided'in which is formed an-axially extending slot 55. The slot 55 functions precisely as the slot 38 shown in Fig. 3111 my preferred form of construction to guide the wire 25 onto and off of the reel.- A second enclosure 5! formed of sheet metal surrounds the entire reel and the cover or enclosure 54 to act as an electrical shield. This in turn is grounded tocut out ignition'noises and the like which might be picked up by thewire and transmitted to the antenna and thence'to the set. In like manner the sheath 40, which connects the reel'5ll and the sleeve I0, is formed identically with the sheath 40 already described. In other words, it consists of a metallic exterior sheath which is grounded to the vehicle frame and a layer of insulation interposed between such sheath and the cable 25;
The knob 60 rotates the reel 5!] to extend or retract theaerial proper. As the handle of either the preferredor modified form of my invention is: turned a cable will be either drawn into or unwound from the corresponding reel. If it is unwound from the reel it-pushes on the rod 20 toextend the antenna as above described. If, on the other hand, the cable is coiledonto the thereel the rod 20 is retracted and the antenna is collapsed. The structure of my invention-may be installedin any desired-place on a motor vehicle, as, for instance, adjacent the cowl -or in one of the bodypillarsr It will be seen from the foregoing description that I have provided a novel coil-up antenna system in which the antenna proper, including the flexible operating member is entirely insulated from an enclosing metallic case, which in turn is grounded to the vehicle. It will further be apparent that the reel in either the preferred or modified form is of such construction that no binding or locking of the parts can take place as the antenna proper is extended or retracted. Also, in place of the cable 25 I may employ a flexible tape or a solid flexible wire as well as the twisted cable shown.
Other modes of applying the principle of my invention may beemployed instead of the one explained, change being made as regards the structure herein disclosed, provided the means statedby any of the following claims or the equivalent of such stated means be employed.
I therefore particularly point out and distinctly claim as my invention:
C1 In an extensible antenna adaptedto be mountedionza-motor vehicle, an antenna mem'ber adapted to be extended or retracted with respect to the vehicle body, a reel 'mounted for rotation adjacent the antenna, a continuous guiding passage in'said reel comprising a series of circumferential convolutions extending about the axis of saidreel, a flexible connecting member secured at oneend to said antenna and at the other end coiled about said reel in the continuouspassage thereof, a metallic container enclosing said reel and electrically insulated fromsaid reel and flexible member, said container having a funnel shaped cap secured thereto, anda tubular metallic sheath extending from said cap to said antenna member, said sheath forming a guide for said flexible member and being insulated from said flexible member and from said antenna member and a ground connection for said sheath.
2-. In an extensible antenna adapted to be mountedon a motor vehicle, an antenna member adapted "to be extended or retracted with respect tothevehicle body, a reel mountedfor rotation adjacent the antenna, a continuous guiding passage in'said reel comprising a series of circumferential convolutions extending about the axis of said reel, 2. flexible connecting member secured at-one end to said antenna and at the other end coiled about said reel in the continuous passage thereof, a metallic container enclosingsaid reel and electrically insulated from said reel and flexible member, said container having a slot int-he periphery thereof,- a hollowcap secured to said container and communicating with said slot, 9. tubular metallic sheath extending from said "cap to said antenna member and in communication with said cap, said flexible member extending through said slot, cap and sheathand electrically insul-atediromsaid sheath, and a ground-connection- -forsaid sheath.
WESLEY J. WHITE.