US1773161A - Scanning device for television - Google Patents

Description

Aug. 19,1930. H. w. BALLARD T AL SCANNING DEVICE FOR TELEVISION Filed Aug. 15, 1928 Harry W. Ballard Jack F Baflard iNVENTORS BY M m wz s Patented- PATENT OFFICE UNITED sures nan! W. BALLAD!) AND JACK I. BALLABD, DETROIT, MICHIGAN SCANNING DEVICE FOR TELEVISION Application filed August 1a, 1928. serial no. 299,232.

This invention relates ,to television and particularly to devices for scanning pictures,

lms and mirrors or the like, such as are used in television apparatus. An object of the invention is to provide a scanning device for television purposes, more com act than present constructions and better esi ned to withstand the necessary high speed 0 the rotative member.

More specifically the object is to mount a stationary light bulb within a rotative cylindrical shell and form said shell with a substantially helical series of apertures through which may be emitted beams of light which, upon rotation of the shell, will successively traverse the surface to be scanned, so as to jointly cover substantially its entire area durin each revolution of said shell.

llhese and various other objects the invention attains by the construction hereinafter described and illustrated in the accompanyingflrawing, wherein: ig. 1 is a view in front elevation of the improved scanning device and its drive motor. I

Fig. 2 is a vertical sectional view of the same taken upon the line 22 of Fig. 1.

In these views the reference character 1 designates a base formed preferably of suitable insulating material such as hard rubber, bakelite or the like. Said base rigidly carries a suitable upstanding socket 2 to receive the shank 3 of a suitable electric bulb 4. The illustrated bulb and socket are of a radio type, primarily designed toreceive television broadcasting, the shank 3 being provided with contact stems 4 (usually four in number) to engage contacts 5 carried by the base within the socket 2, having the usual connection to binding posts 6.

Rigidl embracing the socket 2 and projecting t ereabove is a sleeve 7 on which is journaled a sleeve 8 having a central pulleyforming portion 9 engageable by a drive belt 10. The latter in the illustrated embodiment of the device enga es a driving pulley 11 fast upon the shaft 0 a vertically mounted motor 12. 7

At its upper end the sleeve 8 is enlarged to form a circular head 13 above which engages an annular flange 14 upon the sleeve 7 to maintain the proper engagement of the rotatmg and stationary sleeves. To the head 13 is rigidly secured the lower end of a cylindrical sheet metal shell 15, coaxial with and substantially enclosing the bulb 4.

Exterlorly adjacent to said shell is vertically mounted an opaque plate 16 formed preferably of sheet metal and formed with a central window 17, preferably rectangular and having its central .axis radial to the bulb 4. Said member is supported as described in any suitable manner as for example, by rigidly engaging the lower portion of sald member by a pair of spaced vertical rods 18, horizontally bent at their lower ends and suitably secured to-the lower portion of the sleeve 7 The bulb 4 is preferably of a neon gas type and is silvered or otherwise provided with a reflecting surface, except upon its ortion 19 which faces toward the window 1 The rotating shell 15 is formed with a substantially helical series of apertures 20, for discharging beams of light from the bulb 4 75 through the shell 15, the arrangement being such that when the shell 15 is rotated the beams radiated through said apertures will traverse the window 17 at slightly varying levels and will traverse substantially the entire area of said window during each complete revolution of the shell. Thus a picture, mirror, film or other suitable surface (not shown), mounted for illumination by said beams, will be scanned or traversed thereby through substantially its entire area.

From the foregoing description it is believed that the utility of the described device, particularly in connection with television receiving apparatus, will be clearly evident. The control of the light by a cylindrical shell of the described and illustrated character is much preferable to use of an apertured disc for such purpose since such a shell may be made more compact'than a disc serving a similar purpose and is much better able to withstand the necessary high velocity torque and resulting centrifugal strains. Furthermore, the fact that the described shell can be given a considerably lesser diameter change within the spirit and scope of the subthan a disc serving the same purpose matejournaling said drum upon said socket to rorially reduces such centrifugal strains as comtate about the socket axis, and means for pared to those arising in a scanning disc. actuating the drum in such rotation.

Furthermore, a scannin shell such as this In testimony whereof we sign this speciinvention employs is partlcularl ada ted to fication.

be compactly associated with t e bub and HARRY W. BALLARD. '70 socket which are an essential of such an appa- JACK F. BALLARD. ratus.

While it will be apparent that the illus- 1o trated embodiment of our invention here dis- 7 75 closed is well calculated to adequately fulfill the objects and advanta es primarily stated, it is to be understood t at the invention is susceptible to variation, modification and joined claims.

What we claim is:

1. In a scanning device for television, the

combination with a light bulb, of asubstan- 2o tially opaque cylindrical shell inclosing said 85 bulb and rotative about the bulb axis and formed with a substantially helical series of apertures, means for rotating said shell, and an opaque member mounted exteriorly adjacent to said shell, formed with a window traversed by the rays emitted from said bulb through said apertures.

2. In a scanning device for television, the combination with a base and a socket sur- 80 mounting said base, of a light bulbengaging 95 said socket, a sleeve secured to and pro ectin above said socket, an outer sleeve journale upon the first mentioned sleeve, a substantially opaque cylindrical shell carried by said 85 outer sleeve coaxial with and substantially no inclosin said bulb and formed with asubstantialFy helical series of apertures, means for rotating said outer sleeve together with the shell carried thereby, a member formed of opaque material mounted exteriorly ad- 105 jacent to said shell and formed with a window adapted to be traversed by rays from said bulb, emitted through the apertures of said shell as the latter rotates, and means attaching said window-forming member to 110 said socket.

3. In a scanning device for television, the combination with a base and a socket surmounting said base, of a light bulb engaging said socket, a sleeve secured to and pro ect- 5 ing above said socket, an outer sleeve journaled upon the first mentioned sleeve, a substantially opaque cylindrical shell carried by said outer sleeve coaxial with and substantially inclosing said bulb and formed with a 124) substantially helical series of apertures, and means for rotating said outer sleeve together with the shell carried thereby. 4. In a scanning device for television, the combination with a socket and a lamp in said 126 socket, of a substantially opaque cylindrical shell enclosing said lamp and having its axis substantially coincident with the extended axis of said socket, and formed with a substantially helical series of apertures, means

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