US2764273A - Line number indicator for typewriters - Google Patents

Description

Sept. 25, 1956 E. G. JOHNSON- LINE NUMBER INDICATOR'FOR TYPEWRITERS Filed March 25, 1951 jaws/wok lllllllllllll United States Patent LINE NUMBER INDICATOR FOR TYPEWRITERS Ervin G. Johnson, Oakland, Calif., assignor to Eleanor de Hass Johnson, Oakland, Calif. Application March 23, 1951, Serial No. 217,173 8 Claims. (Cl. 197-489) This invention relates to line number indicators for typewriters and particularly to a device which will unmistakably indicate the particular line of a number of lines turned through by the usual line spacer mechanism of a typewriter.

The device may be more generally called a rotation or angle measuring device in that it indicates the angle through which the platen is rotated by a line spacing and platen setting mechanism.

It is the practice in the general purpose typewriter to make the variable spacing mechanism so that the spaces between lines are acceptably standard, such spacings being six, three, or two line spaces to the inch in this country.

It is often desirable in using a typewriter to be able to determine the serial number of a certain line on a page of typewritten lines with respect to the first line or some other reference point such as the top edge of the sheet. This determination is preferably made without having to turn the sheet back to the initial point, or in any other manner to have to disturb the typewriter mechanism.

It is usual, for instance, to pre-number the lines of the writing sheet, either by printing or by typewriting the numbers on the sheet before the sheet has been typed. Of printing and typing methods the latter is apt to be more accurate in line registration and to present the neater composite appearance. This is so because line spacing mechanisms are essentially constant angle spacing mechanisms and therefore the spacings between the lines of typing are functions also of the radius of the platen plus the thickness of the number of sheets of paper typed upon. Since pre-printed line numbers are necessarily spaced to the nominal spacing of all general purpose typewriters the typewritten lines of individual typewriters often do not register from line number to line number.

Typing the numbers on the sheet is time and labor consuming and oftentimes not desired for other reasons. Accordingly, other devices have been employed in practice with the purpose of informing the typist, while typing a particular sheet, precisely which line she is typing on that particular sheet, without placing any line numbers on the page itself. One example of such a device is a trans-fer sheet (carbon paper) with a strip of pre-printed line numbers along the rig-ht hand edge corresponding to the spacing of all standard typewriters. line number is in this case fixed with respect to the first line of typing because of the operation by the typist known as jogging of the writing and transfer sheets into registry along their leading edges prior to insertion beneath the typewriter platen. All of such carbon sheet line numerals are necessarily alike, and are preset. Due

placed in a zone on the periphery of the platen roll itself. As the platen is rotated by the space feed, the number of the line is indicated by the line indicating numerals. in registration with a pointer fixed on the car- I riage. These devices are usually accurate in registration of the line numbers with the typewritten line because there is a fixed relation between the line space mechanism-and the device. Usually they are fixed with respect to the platen roll, however, and it is difficult to relate the first line to be typed to the first line number of the indicator. Of this class, however, there are some which provide for adjusting the indicator after the typing sheets have been set in place under the platen so that the first line number is in registration with the first line to be typed. Nevertheless, a common characteristic of this class is that the indicator does not distinguish between the numbers of the indicator which appear to identify two or more widely spaced apart lines on the typewritten sheet. For example, in one typewriter, the first, sixteenth, and thirtyfirst lines of a typewritten sheet all register with the indicator scale on the same line, and the scale numbers are therefore all of necessity on the same line. Therefore the typist must distinguish the first, sixteenth, and thirty-first lines by other means, such as by estimating in which portion of the sheet each line occurs. This need follows from the fact that the platen roll repeats its angular position exactly at each complete rotation. I

It is one of the objects of my invention to provide a line number indicating deviceunmistakably indicative of the one line number of the sheet with which it is in registration, and in which no other line number of the sheet is indicated in any manner confusing to the typist.

The devices of the general character referred to have either been prefabricated as an integral part of the typewriting machine itself, or as an integral part of the platen roll, or as a part of the transfer sheet to be used in the typewriter. in the case of all prefabricated machines, the machines which have not been provided with such devices at the time of manufacture, and which are in use, cannot, readily and without expense, be fitted with such devices. In the case of the transfer sheet line indicator, the markings do not permanently characterise the machine. It is another of the objects of my invention to provide for the addition to any existing general purpose typewriter of a line number indicating'device in a manner so that any typist can install the device without the assistance of even a typewriter mechanic.

It is another object of my invention to provide the design for such a device such that it can be made from materials which are generally at hand to the typist. Most of the devices that have heretofore been proposed or employed for this purpose are of necessity manufactured in a factory where their production can be elfected at a minimum of production cost, and cannot be made by a typist. Applicants, invention requires no factory for its manufacture. It can be made and installed by the typist in ten minutes, can be made of the simplest materials and yet give months of service.

The machine-attached devices for indicating the line numbers of typewritten sheets of which I am aware require the expenditure of considerable effort in manufacture, and have not been generally adopted. By the present invention, the desired results are attained by the typist without adding to the initial cost of the machine; moreover, the device does not interfere with operation of the machine because when not needed it is simply ignored. Only in the event indications are desired is the typist required to make certain simple manipulations, and these acts are performed only after the typewritten sheets are fully prepared for typing with the first line of the sheet to be typed upon ready for striking by the type. This makes routine setting of the indicator an easy matter to perform or omit.

It is another object of the invention to provide a simple indicator which functions to indicate with accuracy to the typist when the last line of the page is approach- 'ing. This object is an incident of the function of indicating the number of the page line inasmuch as the page line is referred to the leading edge of the sheet in the usual case.

Other objects and advantages will be evident upon considering the following specification and the accompanying drawing, in which:

Fig. l is a schematic representation of parts of a general purpose typewriter showing the uncompleted device forming part of the invention installed therein, prior to completion;

Fig. 2 is a similar representation with the device completed and in operation; and

Fig. 3 is a fragmentary plan view of part of the device completed, illustrating particularly the relative disposition of the line indicating numerals as rolled out on a fiat plane.

In Figs. 1 and 2 there is illustrated the right hand end of the platen roll of a general purpose typewriter, the roll being fixed to a shaft 12 which is journalled on a carriage, part 14 of which is schematically illustrated in Fig. 2 to form a stop as will be pointed out. Suitable line space, and platen roll detaining, mechanisms are mounted on the carriage, these devices serving to rotate the platen 10, which platen also constitutes a rotating member formed with a continuous rolling surface, through fixed angles, as is well understood by users of typewriting machines. The machines are also provided with clutches by means of which the roll may be shifted with respect to the line space devices for precise registration of type with any particular area of a sheet of paper 16. In addition, and as illustrated in Figs. 1 and 2, the carriage of such general purpose standard machines is provided with pressure rolls 18 and 20. A suitable carriage 22 for these pressure rolls is biased by a spring 24, toward the roll 10; acting, as through a lever 26, pivoted on a stationary pivot 28, and actuated by a hand lever 30. It should be observed that these devices, as illustrated, are merely schematically illustrated and described. It will be understood that there are several rollers 18 on shaft 19, and several rollers on shaft 21. It is pointed out, however, that rollers 18 and 20 here of interest are the right-end-most rollers of each shaft. It is particularly to be observed, moreover, that the rollers may be completely disengaged, and held so disengaged, from the roller 10 and spaced therefrom so that a gap exists for freedom of paper to slide between the rollers. In this Way a large number of sheets of paper with interleaved carbon sheets, may be accommodated between the roll 10 and the rollers 18 and 20. While the rollers are so spaced apart all such sheets are free of tractive engagement with the platen roll and these pressure rollers; and under these conditions all of the leading edges of such sheets may be brought to a common plane of registry with the leading edge 34 of the top sheet, and this edge is positioned parallel with the trailing edge 36. After such registration of the sheets, the rollers 13 and 20 are released to clamp the pack of sheets firmly onto the platen roll. By releasing the roll clutch, the top edge 34 may be placed in exact registry with the line gauge or indicator 33, which indicator 38 is fixed on the frame of the machine in front of the platen roll 10 and the top sheet of typing paper. Such an indicator may also be fixed to the carriage adjacent the right end of the platen roll, or on some device which moves with the carriage. The clutch is then engaged and the top edge 34 is fed upwardly by the line space mechanism as many line spaces as are desired to the first line to be typed upon. This line is illustrated at 40 in Fig. 2, but it is not necessarily present on sheet 16, nor need it be placed there except for the present purpose of explanation.

The foregoing description sets out the construction of features of typewriters as found in general use and which in some measure afiect the present invention. The in- 'used ordinary sixteen pound typewriter paper.

eter than the external perimeter or circumference of the platen roll, the difference at least being suflicient to allow the tube to slip freely circumferentially on the platen roll when free of the idler rollers, and also suf-- ficient so that the typed numbers on the tube will not occur on the same axial line, as will appear. The tube" circumferential perimeter is uniform from end 42a to end 4217. In the drawing, the left end 42a of tube 42- is shown to terminate at rollers 18 and 20, in Fig. 2 roller 20 being shown in section at the plane of termination of tube 42. For some purposes the tube 42 may terminate to the right of rollers 18 and 20, provided it is overlapped by the copy sheets as shown. The right end of tube 42 is shown abutting a part 14 of the carriage, although such abutment often does not occur and depends upon the manner of installation of the tube by the typist. These limits, however, determine the tube length which will work satisfactorily even if the tube circumference is not precisely the same from end to end, because the tube cannot work rightward from clamping engagement with rollers 18, 20, and 1%; it remaining of necessity because of its length, to some extent between these rollers, or between the roller and the sheets, as seen in Fig. 2. It is not necessary oftentimes that this abutment 14 be employed, because the tube often does not move right or left as it is rotated.

It will be observed that the rollers 18 and 2.0 with their controls, constitute means for causing members 10 and 42 to contact for rolling engagement and means for causing the two members to be released from rolling engagement.

The internal perimeter of tube 42 is described as greater than the external perimeter of the platen roll 10. The difference in their perimeters is made sufficient to allow the tube to slip loosely on the roll when released by rollers 18 and 20. To this extent the drawing Figs. 1 and 2 greatly exaggerate this difference with the purpose only to visually emphasize the fact that there is a difierence in perimeters; that there is this difference is essential to the ultimate function of the invention as will appear.

The tube 42 may be prefabricated in tubular form for machines having easily removed platen rolls 10, in which case it may be flattened between the time of manufacture and the time of installation; and upon installation the platen roll is lifted out of the typewriter, the tube 42 slipped over its end, and the assembly replaced in the typewriter in the relationship shown.

The tube 42 will, in many cases, be partially fabricated in situ. The sheet from which it is made is selected with parallel end edges 42a and 42b, then inserted under the platen. With end portions of the respective edges 42a and 42b in registry while loosely wrapped about the roll 10, the sheet is marked at both ends for cutting to the required perimetral length as described above. The sheet is then removed and cut, preferably squarely, off. The sheet is then replaced around the roll 10 and the cutoff edges brought to matching registry as along edges 44, and the edges fixed in abutting relation with a narrow adhesive strip of paper, or tape.

The tube having been completely installed on the typewriter roll to have its right edge near to the part 14 of the carriage, the correct position for placing indicator numerals, or marks thereon is next determined by inserting a sheet 16 of the paper to be typed on in normal typing position under the platen. Its edge 16b shows that the indicating numerals must be placed rightward of edge 16b in order to be visible. The numerals 1 through 33 have been illustrated typed on tube 42 in Fig. 2 as they The tube 42 constitutes a mem occur when the double space is used. It will be observed that the number 16 is offset rightward from the precedmg numeral 15. It will, moreover, be observed that the numeral 16 occurs at a position on the tube peripherally offset from the numeral 1, or, the circumferential distance on the marked surface of tube 42 between these two marks 1 and 16 is other than, and as shown, less than, the circumferential distance around the tube from numeral 1 and to numeral 1; and that the numeral 1 is likewise offset from the numeral 31. In Fig. 3 it is evident that no two indicating numerals occur in registry on the same axial line of the tube. This is an important characteristic of the invention resulting from the difference in peripheral length of the tube and the roller being more, or less, preferably less, than one line space, and when more, always including a fraction of a line space. It follows, therefore, that the value of the distance be tween any two adjoining numerals or marks, as the distance between numerals 2 and 3 on tube 42, is arithmetically indivisible into the distance on the surface of tube 42 from mark 1 to mark 1 (which is the distance around tube 42 on the marked surface) a whole number of times. Because of this construction, when the bottom of numeral 1 has been set in registry with the top edge of line indicator 38 as shown in Fig. 2, each succeeding line appears in such registry as the line feed is operated. Thus, when 16 lines have been spaced, the bottom of numeral 16 lies in exact registry with the top edge of line gage 38. Moreover, at this time, the numeral 1 is covered by gage 38, and 31 is above gage 38. It is, therefore, unmistakably known that the line of the sheet is the 16th line.

It will be observed that the adjoining marks are separated by an arc which connotes a displacement of 24 geometrical degrees of angle, and that the fifteen spaces from 1 to 16 connote one full rotation of the member 10; similarly the numeral 32 connotes a second full rotation. The marks 1 to 15, inclusive, are one group and the marks 16 to 30, inclusive, are a second group, and the two groups constitute a single progressive series of numbers which are circumferentially equispaced and which progression is in a circumferential direction.

In using the line indicator, the various copy sheets 16 are set in place for the first line to be typed thereon as indicated in Fig. 2. The typist then presses the fingers of the left hand firmly against the sheets 16 thus tem porarily using the fingers to clamp the sheets in place on the platen, while releasing the rolls 18 and 20 with lever 30. The tube 42 is now free for rotary sliding about platen roll 10. The typist effects this rotation of tube 42 with the right hand index finger, dragging on the exposed part of tube 42, sliding it so that numeral 1 appears as shown in Fig. 2 in registry with gage 38. Clamp 30 is now released and the device, along with the typewriter, is ready for typing the sheet. As each line space is effected the serial number of that line is indicated in exact registry with the gage 38.

The reason for restricting the amount of the left end of tube 42 to a short length to be lapped with sheets 16 is now more easily understood. It reduces the amount of frictional resistance to this adjustment by the fingers, allowing free rotation of the tube between the platen roll and the sheets of copy and carbon paper. It also tends to prevent leftward creep of the tube.

It is also believed to be clear that the web of tube 42 is preferably quite thin and relatively inelastic in .its own plane. Thinness prevents unevenness of the feeding of the sheets 16 at the two sides of the paper. The surface finish of the tube 42 is, particularly in the lapping region referred to, reasonably smooth. The tube 42 may, of course, be fabricated of a more durable material than the paper referred to, as will occur to those familiar with sheet materials.

I claim:

1. The method of forming a line number indicator for typewriters having cylindrical platen rolls which method comprises forming a tube of thin flexible sheet material about the platen roll to a circumference sufliciently greater than the circumference of said roll to have a loose and freely rotative fit thereon, and thereafter utilizing'the typewriter to place line numbers thereon.

2. The method of claim 1, with the tube being held to the platen roll to prevent slippage therebetween.

3. The method of claim 2, the last step further comprising placing numerals in peripheral groups, each group being on a separate longitudinal area and extending substantially through a full rotation of the tube, the numbers in each group being progressive and progressing from one group to the next adjacent group to form a single progressive series of circumferentially equispaced numbers.

4. A rotation measuring device comprising, in combination: a first rotating member formed with a continuous rolling surface; a second member formed with at least one continuous rolling surface for continuous rolling engagement with the surface of said first member; and a plurality of groups of marks forming a series of marks on one surface of said second member, each of said groups arranged in the direction of rolling movement thereof for indicating incremental rotations of said first member; the distance on, and in the direction of rolling of, said marked surface between two marks in said series being other than the distance around said marked surface, the marks in said series adjoining each other in the direction of rolling movement being equally spaced apart, and the equal spacing of the marks being such as to be arithmetically indivisible into the distance around said marked surface a whole number of times whereby no two marks occupy the same line normal to such direction on said marked surface.

5. A rotation measuring device according to claim 4 and further including in combination with the structure thereof; an indicating member, means positioning the indicator member in a position adjoining the path of movement of the marks on said marked surface, and means for setting a position of the first rotating member such that when one of the marks adjoins the indicating member the mark connotes an angle through which the first member has been rotated.

6. A rotation measuring device according to claim 4, and further including in combination with the structure thereof, means for causing the two members to contact for rolling engagement and means for causing the two members to be released from rolling engagement whereby one member may be adjusted in rotation with respect to the other member.

7. A line number indicator for typewriters having a cylindrical platen roll, comprising: a tube of thin flexible material of a size to be loosely circumjacent such roll, and on said tube a progressive series of circumferentially equispaced numbers progressive circumferentially of and a distance greater than the circumference of said tube, the ratio of such circumference to said space being a non-whole-number.

8. The combination of claim 7 in which said series of numbers form and are divided into a plurality of parallel spaced apart groups.

References Cited in the file of this patent UNITED STATES PATENTS 545,233 Keith Aug. 27, 1895 771,224 Bellamy Oct. 4, 1904 889,918 Farmer June 9, 1908 1,013,953 Richardson Jan. 9, 1912 1,228,637 Barnard June 5, 1917 1,376,996 Beland May 3, 1921 1,844,992 Thurban Feb. 16, 1932 1,938,371 Bottle Dec. 5, 1933 FOREIGN PATENTS 77,391 Switzerland Apr. 16, 1918

Images