US2203461A

US2203461A - Continuous sheet facsimile system

Info

Publication number: US2203461A
Application number: US123770A
Authority: US
Inventors: William G H Finch
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-02-03
Filing date: 1937-02-03
Publication date: 1940-06-04
Anticipated expiration: 1957-06-04

Description

June 4, 1940. w. G. H. FlNcH CONTINUOUS SHEET FACSIMILE SYSTEM Filed Feb. 3, 1937 3 SheetS-Sheet 1 Fig! 2 zNvgsNToR. williamrg.3f,)5`znch ATFORNEY.

June 4, 1940. w, G, H FxNcH CONTINUOUS SHEET FACSIMILE SYSTEM 3 Sheets-Sheet 15 Filed Feb. 5, 1957 JNVENTOR.

ATTORNEY.

Patented June 4, 1940 UNITED STATES PATENT OFFICE 2,203,461 CONTINUOUS SHEET FACSIMILE SYSTEM William G. H. Finch, Spuyten Duyvil', N. Y.

Application February 3, 1937, Serial No.

11 Claims.

This invention relates to facsimile systems and more particularly relates to mobile transmitters employingr pictures or messages to be transmitted from a continuously fed sheet.

5 The objectsof my present .invention reside in providing a rugged, compact, mobile facsimile transmitting unit of a fool-proof and light weight provide improved scanning mechaparticularly useful for home broadcasting or aircraft, ship and automobile use and where a compact and relatively inexpensive system is required. Figure 1 is an elevation of a mobile transmitter with the cover removed.

Figure 2 is a plan view of the transmitter unit. Figure 3 is an enlarged 'cross-sectional view taken along 3-3 of Figure 2 illustrating details of the scanner and sheet feeding mechanism.

Figure 4 is a cross-sectional view taken along 4 4 of Figure 3 through the light source.

Figure 5 is a partial plan view coresponding to the section taken along 5-5 of Figure l.

Figure 6 is a front view of the flexible spring for clamping the record sheet in scanning position.

Figure 7 is a portion of Figure 5 illustrating the flexible Sheet hOiing spring in open position.

Figures 3 and 9 are detail views of the sheet feeding mechanism.

Referring t0 the figures and more particularly to Figures 1 and 2,' there is shown a cast iron during the operation of the transmitter unit. I a synchronous motor for con-v nection to a standard alternating current source such as sixty cycles and operative at, for example,- 1800 revolutions per minute. It is to be underu stood that a similar motor is -employed at the `associated receiving units.- 'I'he shaft of motor I I is geared down to the scanning speed by suitmobile facsimilefwork is sixty lines per minute corresponding to sixty revolutions per minuteof; the vertical driven shaft I3 positively connectedv to themotor Il at the reduction gearing within casing I2. 'Ihe bottom of driven shaft I3 is l5 connectedv to gear I4 which: drives thel camv Il through a. gear I6 meshing therewith vand attached to cam I5. Cam I5 osclllates the opticalscanning mechanism I1 horizontally across the record sheet I8. A cam follower I9 coacts with 20 the cam I5 to operate the scanning mechanism in a manner to-be described in more detail hereadvancing the record sheet I8 25 oscillating scanner I1. I8 may be inserted in the scanning system for scanning an opaque record sheet so that the actual messages and pictures may be directly transmitted. However, modif-1- cations such as described in my reissue patent 85 referred to above may be made for transmission of translucent records.

'I'he electrical circuits and components for translating the electrooptical impulses and providing the synchronizing signals are not illus- 40 be housed within the illustrated unit and upon the base II) thereof.

I9 is attached to rod 23 by a suitable bracket 26. Rod 23 is rotatably mounted in its supporting structure to permit the oscillation of the optical system 1.

The source of light for the optical system comprises an electric bulb 21 with its filament supported 'opposite a telescoping condensing lens system 28 focussed upon the record sheet I8. 'I'he diameter of the spot of light focussed upon sheet I8 is substantially equal to the width of the scanning line. Accordingly, where sixty line per inch of scanning is employed, a spot about 1/60 in diameter is used. The record sheet I8 will accordingly progress one inch per minute through the transmitter when sixty lines per inch and sixty revolutions per minute are used. It is to be understood that different speeds and rates may be incorporated in practical designs.

A photoelectric cell is enclosed in the tubular housing 38 supported by a plate 3| attached to the lamp enclosure 32. A lens system 33 projects from the tubular housing 30 for focusing a portion of the refracted light rays 34 from the sheet I8 to the photoelectric cell not shown. The electrooptical technique of generating a light beam and focusing upon a photoelectric cell to transform the Varying light intensities of the transmitted picture I8 into corresponding varying electrical currents to be transmitted, is well known in the facsimile art. However, the novel and compact arrangement of the scanning mechanism I1 upon the oscillating shaft 23 simplies the construction. The photoelectric cell is oscillated across the continuous sheet I8 together with the lens system 28 to continuously scan the record sheet I8 line by line. The picture sheet I8 is advanced one line corresponding to each oscillation of the electrooptical scanner I1 as will be described hereinafter.

The light source 21 may be focused into a sharp beam 35 by suitably positioning its filament with respect to the condensing lens system 28. Figure 4 is a cross-sectional view taken along the horizontally disposed lamp 21 along 4-4 of Figure 3 to illustrate the eccentric mounting of the lamp 21 for adjusting the position in a simple manner. The lamp 21 is mounted in a circular supporting base 39 and in a tube 31 projecting from base 39 positioned oil" center with respect to the base 39. The base 39 is rotatably supported in the -lamp housing 32. By manual rotation of the tube 31 and base 39, the off center position of the tube 31 will correspondingly cause the lamp 21 to move closer to or further away from the optical system 28. Adjustment as much as 33%" may readily be performed by this arrangement. The condensing lens system 28 may further be telescoped in the well known manner to aid in proper focussing of the sharp beam 35.

The optical system I1 may be raised sufficient to cause the axis of the condensing lens system 28 to be raised above the opaque block 36 so that the beam 35 may project beyond the transmitter unit, the record sheet I8 not being in position at this time so that av sharp focusing of the beam is facilitated. A hollow tube 38 projects from the lamp enclosure 32. A cap 48 is attached to the top of hollow tube 38 in spaced relation to permit circulation of air to the lamp 21 for ventilation and cooling.

Figure 5 is a partial plan view corresponding to the section taken along 5 5 of Figure 1 illustrating in more detail the scanning actuation of the electrooptical system by the cam I5 continuously rotated by the motor. 'Ihe cam follower I9 is mechanically biased against the cam I5 by means of a spring 4I connected between the follower bracket 26 and a frame portion 42. The surface of the cam moves the follower I9 to the extreme positions I9 and I9 shown in dotted. The outer position I9' corresponds to the point 43 at the maximum radius of the cam I5; the inner position I9, to the point 44 at the minimum radius. The dot dash circle 45 corresponds to the locus of the movement of point 43; the smaller circle 46, to the movement of the inner point 44. For each rotation of cam I5 the optical system I1 is oscillated back and forth once horizontally across the sheet I8. The optical scanning of the picture shading occurs during one traverse of the sheet I8; and the synchronizing signal and sheet advancing actuation occurs during the return or opposite motion of the scanning mechanism I1.

In order to insure quality scanning, the record sheet I8 must be held firmly in position opposite the oscillating scanner. However, for ease of insertion and removal of the sheet I8 from the unit, means are provided for disengaging the sheet from its rigidly held position. The important feature of my present invention resides in the improved sheet engaging and disengaging mechanism to perform this operation with a minimum of effort from the operator. Figure 6 shows a leaf spring 41 pressing against the block 36 with the record sheet I8 held in position therebetween. A slot 48 provided across the central portion of the spring 41 corresponds to the section of the sheet I8 to be scanned. The relation between the scanning beams 34 and 35, the leaf spring 41, the record sheet I8, and the opaque block 36 is clearly illustrated in Figure 3. The flat spring 41 presses the sheet I8 firmly against the opaque block 36 to hold it in scanning relationship. However, sheet I8 may be moved from engagement with the spring 41 and block 36, the sheet feeding force overcoming the frictional engagement of the sheet I8 at this point. I prefer to use an opaque block 36 for supporting the sheet I8 at the portion being scanned in order to permit better contrast during the scanning operation.

One end 5I) of the fiexible or spring plate 41 is pivotally supported at a bracket 5I attached to the block 36. The opposite end 52 of the sheet spring 41 is attached to one end of lever 53 which permits manual engagement or disengagement of the spring 41 against the record sheet I8. 'I'he end 52 of spring 41 presses against the curved end 54 of lever 53. Spring 41 normally tends to assume the open position illustrated in Figure 7 whereby the sheet I8 is not held in iirm engagement opposite the lens system 28. The pivoted lever 53 is mechanically biased by spring 55 to force the end 52 of leaf spring 41 inwardly forcing the flexed spring 41 to press the sheet I8 against the block 36 and hold it in proper engagement. To maintain the spring 41 in the unengaged position shown in Figure 7, a latch 56 is clearly illustrated in Figures 7 and 8. When the latch 56 is released from lever 53 the spring 41 is snapped against the record sheet I8 due to the biasing action of spring 55.

Further means for holding the record sheet I8 in proper alignment is provided near the top of the

machine by'coacting rollers

51 and 58. These are preferably rubber rollers for frictionally engaging the sheet I8. The larger roller 51 is connected to a shaft 68. A hand lever 64 is attached to one end of a shaft 60 for manually advancing the record sheet I8 through the facsimile unit. The line by line advancing mechanism 2| is attached to the opposite end of the shaft 60 for automatically advancing the sheet I8 during the scanning operation in a manner to be described. Smaller roller 58 is an idler or presser roller for maintaining the sheet I8 in frictional engagement with the roller 51. The roller 58 may be formed in two sections as illustrated in its plan view in Figure 2.

The presser roller 58 is arranged to be snapped into position against the sheet I8 and roller 5l or, conversely, snapped out of engaging position. 'I'he dotted position 58 shown in Figure 3 illustrates the out of engagement position of presser roller 58. The opposite supporting arms 63 for the roller 58 are connected to corresponding springs 62 attached between the arm and the uprights 64. Springs 62 maintain the presser rollers 58 in engaged or disengaged position by the off center action as illustrated.

Figure 8 is an enlarged end View of the pawl and ratchet line by line advancing mechanism 2|. The rocker arm 65 is moved back and forth by the cam 20 shown in Figure l. A follower 66 coacts with the cam to rock lever 61 and correspondingly move rod 65 to and fro. The end 68 of rod 65 is pivoted to a feed pawl 18. The pawl l0 engages the teeth of ratchet wheel 1I. Ratchet wheel 1I is attached to the shaft 68 of feed roller 51 (Figure 3). Feed pawl 'I0 is pivoted on arm 'I2 and spring biased into engagement With the teeth of ratchet wheel 1|. A further pawl 'I3 is spring biased against the ratchet wheel II to prevent reverse rotation of the ratchet wheel and the sheet feeding mechanism. For each rotation of the cam 20, rod 65 will be rocked once to advance the ratchet wheel II by one tooth. The record sheet I8 will be advanced by a distance equal to one scanning line in response to this operation as will now be understood.

Figure 9 is an enlarged detail view corresponding to 9--9 of Figure 2 illustrating the coaction between the ratchet wheel 1I and the feed roller 51. A pinion I4 is secured coaxially with ratchet wheel II across the upright 64 and engages with a gear 'l5 attached to the shaft 60 of roller 51. The gearing ratios and diameters of the components of the feeding mechanism are arranged so that the advancement of one tooth of ratchet wheel 'II will move the record sheet by a distance equal to the width of one scanning line.

Although I have described a preferred embodiment for my present invention, modifications may be made by those skilled in the art which fall within the broader spirit and scope of my present invention and accordingly I do not intend to be limited except as set forth in the following claims:

I claim:

1. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a at flexible plate; an arcuate member substantially coextensive with said plate, the sheet being placeable between said plate and said member; and means for pressing said plate against said sheet to cause said sheet to continuously conform with said arcuate member transversely across the sheet and to frictionally engage said sheet between said plate and member.

2. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a ilat flexible plate; an arcuate member substantially coextensive with said plate, the sheet being placeable between said plate and said member; means for normally pressing said plate against said sheet to cause said sheet to continuously conform with said arcuate member transversely across the sheet and to frictionally engage said sheet between said plate and member; and manually operable means coactable with said pressing means for holding said plate in open position.

3. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a flat spring having a transverse slot; an arcuate member substantially coextensive with said spring; said transverse slot being positioned opposite the line of scanning and the sheet being placeable between said flat spring and said member; and means for pressing said at spring against said sheet to cause said sheet to continuously conform with said arcuate member transversely across the sheet and to frictionally engage said sheet therebetween.

4. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a iiexible plate; an arcuate member, one end of said plate being pivotally attached to said member, the sheet being placeable between said plate and said member; and means for pressing sa-id exible plate against said sheet to cause said sheet to continuously conform with said arcuate member transversely across the sheet and to frictionally engage said sheet between said plate and member.

5. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a fiat spring having a transverse opening; a member, one end of said sheet spring being attached to said member; said transverse opening being positioned opposite the line of scanning and the sheet being placeable between said flat spring and said member; and means for pressing said fiat spring against said sheet to cause said sheet to continuously conform with said member transversely across the sheet and to frictionally engage said sheet therebetween comprising a lever coasting with the other end of said flat spring for flexing said spring against the member.

6. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a flexible plate having a transverse slot; an arcuate member of opaque material, one end of said plate being pivotally attached to said member; said slot being positioned opposite the line of scanning, the sheet being placeable between said plate and said member; and means for pressing said plate against said sheet to cause said sheet to continuously conform with said arcuate member transversely across the sheet and to frictionally engage said sheet therebetween comprising a spring biased lever coacting with the other end of said plate for flexing said plate against the member, whereby the line-byline scanning of the gripped sheet occurs across said slot.

7. Mechanism for maintaining a sheet in arcuate alignment for line-by-line scanning comprising a iiat exible plate having a transverse slot; an arcuate member of opaque material, one end of said plate being pivotally attached to said member, said transverse slot being positioned oppcsite said scanner, the sheet being placeable between said plate and said member; means for pressing said plate against said sheet to cause said sheet to continuously conform with said arcuate member transversely across the sheet and to-frictionally engage said sheet therebetween comprising a spring biased lever coacting with the other end of said plate for flexing said plate against the member, whereby the scanning of the .gripped sheet occurs across said slot; and manually operable means coactable with said pressing means for holding said plate in open position consisting of a latch for engaging with said lever.

8. In facsimile scanning apparatus, an arcuate platen, a sheet thereon, spring pressed clamps for holding said sheet upon the convex surface of said platen at a plurality of points thereon, means common to all said clamps to raise same to release said sheet, a member movable over the sheet, and translating means carried by said member and adapted to contact said sheet.

9. In facsimile scanning apparatus, an arcuate platen, a sheet thereon, spring pressed means for holding said sheet upon the convex surface of said platen at a plurality of points thereon, means common to all said clamps to raise same to release said sheet, means for moving said sheetacross said platen step-by-step, a member movable over the sheet, and translating means car-1 ried by said member and adapted to cooperate with said sheet when same is stationary on said platen.

10. In facsimile scanning apparatus, a convex stationary platen, a sheet supported on the convex face of said platen, means comprising resiliently mounted arcuate clamps engaging said sheet and extending transversely across the same adjacent to the ends of said platen, and means common to said clamps for disengaging them from said paper.

11. In facsimile scanning apparatus, a convex stationary platen, a sheet supported on the convex face of said platen, a pair of arcuate clamping members extending transversely across said sheet for holding the latter in intimate contact with said platen, a translating device and means for moving the same in a path between said clamping members, and means common to said clamping members for raising them to a position spaced apart from said platen.

WILLIAM G. H. FINCH.