US2777744A - Facsimile recorder - Google Patents

Description

1957 R. G. OLDEN ET AL 2,777,744

FACSIMILE RECORDER Filed June 2, 1955 2 Sheets-Sheet l INVENTORS. CHARLES J. YOUNG ROGER G. OLDEN A TTOR/VEY Jan. 15, 1957 R. G. OLDEN ET AL 2,777,744

FACSIMILE RECORDER Filed June 2, 1955 2 Sheets-Sheet 2 43 FIG.3

INVENTORS, CHARLES J. YOUNG ROGER G. OLDEN A TTOENEY FACSIMILE RECORDER Roger G. Oiden and Charles J. Young, Princeton, N. 3.,

assignors to the United States of America as represented by the Secretary of the Army Application June 2, 1955, Serial No. 512,901

3 Claims. (Cl. 346-74) The present invention relates to a facsimile recorder and more particularly, but not necessarily exclusively, to a continuous electrolytic recorder of a size suitable for reproducing sheets up to 32 X 40 inches.

While not so limited, the invention is particularly adapted to that form of facsimile recording apparatus wherein the reproduced message is built up in a point-by-point manner on a recording paper or strip upon which the message is to be produced. In the present embodiment the invention will be described in relation to the reproduction of maps in size up to 32 X 40 inches, but is not so limited. Such systems are usually those where the recording on the record sheet takes place by reason of a current flowing directly through the medium upon which the record is to be produced, and accordingly such systems are generally known in the art as recorders of the so-called electrolytic type, although it is to be understood that in some instances the recordings may develop as the result of heat or the like produced by current flowing between two suitable electrodes with the recording material interposed therebetween.

In its application to the so-called electrolytic type of recording, as illustrated in one form, for instance by Young Patent 2,215,806, a recording sheet or strip is arranged to be impregnated with a chemical solution which is suitably changed when signal current flows through it, so that marking effects are obtained upon the material of the recording sheet. The impregnated paper is suitably advanced relative to the recording drum and the printer bar so as to bring new sections of the recording paper beneath the printer bar. Signal energy as it is received from the communication channel after being suitably amplified, is caused to initiate the flow of current between the printer bar on the one hand, serving as one electrode of the system, and the recording helix on the helix drum, serving as the other electrode on the other hand. The density of the marking in the recording strip is genererally proportional to the intensity of the current flowing.

In facsimile systems of the type set forth above, satisfactory and adequate results in the reproduction f sheets or strips up to and including 8 /2 inches wide have been obtained. However, when prior attempts were made to reproduce strips or sheets of width substantially greater than those set forth above, as for example about 36 inches wide, it was found that faithful and satisfactory results could not be obtained due primarily to wrinkling of the paper and of the premature drying of the paper immediately prior to the printing operation. Until such deficiencies were overcome, it was obvious that satisfactory reproduction of relatively large sheets could not be accomplished. It has been found that sheets up to 34 inches wide of the type used in facsimile recorders increased as much as one inch when wet. To secure satisfactory results it was necessary that such expansion or stretch in the paper be compensated for before the printing step. necessary to incorporate an added rewetting stage into such a device so that the recording paper would be suf- In addition, it was found nited States Patent ficiently impregnated with electrolyte so that reproduction of the markings could be effected.

Accordingly, the primary object of this invention is to provide an electrolytic recorder that can satisfactorily operate with sheets up to 32 x 40 inches.

An important feature of the invention is the provision of means for avoiding wrinkling of relatively large sheets of recording paper prior to and immediately following its printing operation.

Another feature of the invention is the provision of means to produce a facsimile system wherein the time of paper run between the wetting tank and the printer is maintained at a minimum.

Another feature of the invention is to provide means for a rewetting procedure to maintain sufiicient moisture content in the paper at the time it reaches the bar. Such is necessary in view of the fact that if the reproduction paper is unduly dry at the time it reaches the printing means unsatisfactory results will ensue.

Another feature of the invention resides in the ease and facility in cleaning out the rewetting cylinders as hereinafter described.

Other objects and features of the invention will become apparent from a reading of the following specification in connection with the accompanying drawings in which:

Figure l is a view in perspective of a preferred embodiment of a recorder embodying the present invention;

Figure 2 is a View, partly in cross section and partly in elevation, of the recorder shown in Figure 1;

Figure 3 is a partial elevational view of one of the crowned rollers adapted to rewet the recorder paper in its path of travel;

Figure 4 is an end view of the roller shown in Figure 3, and

Figure 5 is a partial cross-sectional View of the roller shown in Figure 3, and its driving mechanism.

Referring to the drawings, particularly to Figures 1 and 2, there is shown the recorder designated generally as 10 of open box-like configuration and including in part support members 30 and 31. In the description that ensues there will be described a plurality of idler rollers, drums and the like confined within the recorder 10. For brevity and convenience in describing the device herein, no detailed description will be made of nor any assignment of numbering will be given to the various shafts and appurtenant bearings which serve to support all the drums and rollers in the device.

Longitudinally positioned between, and supported in, the members 30 and 31 is a rotatable reel 14 from which the recording paper 27 is unwound to be fed through the various components of the device. In this particular embodiment the reel is at least long enough to accommodate paper or widths up to 34 inches. Spaced from and slightly above the reel 14 is an idler roller 15 which serves to guide and urge the paper onward in its travel from the reel 14 to its immediate component in the apparatus which is a trough 24 containing an electrolyte solution 25 which serves to impregnate the paper 27 as conventionally accomplished in electrolyte type recorders. The electrolyte 25 may be any chemical solution which, when placed on a recording paper and subjected to an electric potential, will react to form a discoloration on the surface of the paper. The trough 24 is suitably held by brackets or the like between the supports 30 and 31. Also within the trough 24 and extending longitudinally therethrough, is a second idler roller 16 which is located adjacent to the base of the trough but spaced sufficiently therefrom so as to permit the paper 27 to be guided beneath the roller to insure that the paper 27 will become thoroughly impregnated with the electrolyte within the trough. The roller 16 also serves to guide and urge Patented Jan. 15, 1957 the .paper 27 in its travel to the next component device in the recorder.

It has been ascertained from many earlier tests that recording paper of approximately 34 width increases approximately one inch in Width when Wetted With electrolytic solution. If such spreading or expansion of the paper is not taken up the paper will wrinkle thereby seriously interfering with a good finished picture. It is therefore necessary that such wrinkles be taken up prior to the time that the paper reaches the printing operation. The first of such takeup means is a driven guide roller 17 over which the paper is passed after its emergence from the trough 24. Guide roller 17 is longitudinally positioned between support members 30 and 31 and supported in well known manner. The guide roller 17 is not a true cylinder but is provided with di-minishingly smaller cross-sectional area as it approaches the respective ends of the cylinder so that its intermediate portion has a cross-sectional area greater than at its ends. In effect, such a configuration provides a roller which assumes a crown in its medial portion. By utilizing such a crown. pattern the paper is spread in its travel over the guide roller 17 to compensate for the expansion of the paper and will thus remove any wrinkles therein and the paper will leave the-roller 17 in a non-wrinkled condition. The paper, after being so spread, is then passed over another driven crowned roller 18 which rotates in a direction opposite to the movement of the paper, and which is similarly located longitudinally within the recorder and extends partially into the trough 24. Crowned roller 18 is shown partially in section in Figure and its crowned portion is shown as 18 constituting the medial portion of the linear roller 18. The amount of crowning or enlargement of the medial portion of the roller 18 is substantially similar to that present in crowned roller 17 described supra. The crowned roller 13 is further characterized'by having a well 50 therein sealed at one end by wall 51. The other end of well 50 is terminated by a bearing 53 which is partially cut away to provide a passageway 57 for the electrolyte 25 into the well 50 as hereinafter described. The roller 18 is further provided with two helical grooves 55 and 55 starting substantially in the mid portion of the cylinder and extending to the respective opposite ends of the roller in opposite direction of hand. At the juncture of said helical grooves in the central portion of the cylinder 18, there is provided a small opening 35 extending into well 50. Afiixed to the periphery of one end of the cylinder 18 is an open-ended scoop 43 which in its movement through the trough 24 is adapted to scoop up liquid electrolyte and impel it into the well 50 through passageway 57. The small hole inthe medial portion of the roller 13 discharges a small amount of electrolyte onto the paper and into the two helical grooves. These being on opposite hand, transport'and spread the liquid across the width of the paper. Any excess electrolyte drops the back into the trough 24 from which it is picked up by the scoop 43 and put back into the well 50. Since the amount of liquid picked up by the scoop is greater than that discharged from the hole, a certain amount of electrolyte is'stored inside the roller 18 which enables the wetting operation to continue even after the liquid level in the trough 24 has dropped beyond the reach of the scoop. However, when the paper begins to dry out, more solution should be added to the trough 24. At the completion of a days operation, it is desirable that any liquid electrolyte be removed from the well due to its caking and corrosive action. This is accomplished by providing a plunger 47 in bearing 53 which can be operated by a protruding handle 41. By using the plunger, the old electrolyte solution can be removed and the inside of roller 18 can be rinsed by filling the trough with water. It is thus readily apparent that as the recorder paper travels over the cylinder 18 it will be tightly stretched by reason of the fact that the cylinder rotates against the travel of the paper and applies friction thereto. The crowned portion of the roller 18 also serves to spread the paper as hereinbefore described. After leaving the roller 18, the paper is passed between the drums 11 and 12, the drum 11 being the printing drum and drum 12 being the scanning helix drum. The paper after leaving the printing contact point travels upwardly over another crowned roller 19 which is substantially of the same shape and design as the crowned rollers 17 and 18 to further remove any minute wrinkles that might be present in the paper. The final stage in the completion of the printing is accomplished by passing the paper over the fixing lamp shown at 20 and then through a pair of idler rollers 28 and 13 and out of the machine. The recorder is further provided with two handles 57 and 59. The handle 57 serves as a means for separating the printing drum 11 and the scanning drum 12 in order to permit the threading of the paper 27 therethrough. Similarly the spring urged handle 59 permits separation of the rollers 13 and 28 for the same reason.

While there have been described what are at present considered to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and it is, therefore, aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. In combination in a facsimile system, a recording paper feed means, a printing means, means including a trough for wetting said paper with a liquid, and a plurality of guide rollers intermediate the paper feed and the printing means, one of said rollers extending partially into said trough, said last mentioned roller including means for withdrawing liquid from said trough and depositing it into the interior of said roller, and means on said roller for permitting escape of said liquid from said roller to wet said recording paper in its passage over said roller.

2. In a system of the kind set forth in claim 1 wherein said means for withdrawing liquid comprises an openended scoop affixed to said last mentioned roller.

3. In a system of the kind set forth in claim 1 wherein the means on the roller for permitting escape of liquid from the interior of said roller includes at least one opening extending through said roller.

References Cited in the file of this patent UNITED STATES PATENTS 457,255 Cox Aug. -4, 1891 2,590,699 Heyer Mar. 25, 1952 2,609,440 Goldsmith Sept. 2, 1952 2,619,401 Greig Nov. 25, 1952 FOREIGN PATENTS 1,038,338 France May 6, 1953

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