US2907439A - Portable duplicating attachment - Google Patents

Description

- Oct. 6, 1959 w. P. HUSTON, JR 2,907,439

' PORTABLE DUPLICATING ATTACHMENT Filed Feb. 20, 1957 2 Sheets-Sheet 1 lNl/ENTOR WILLIAM E HUS TON, JR.

AGENT Oct. 6, 1959 w. P. HUSTON, JR

PORTABLE DUPLICATING ATTACHMENT 2 Sheets-Sheet 2 'Filed Feb. 20, 1957 INVENTOR WILL/AM HUS TON A 65 N T United States Patent 6 PORTABLE DUPLICATING ATTACHMENT William P. Huston, Jr., Miami Shores, Fla.,. assignor to Mul-T-Typer Corp., Miami, Fla, a corporation of Florida ApplicationFebruary 20, 1957', Serial No. 641,299

16 Claims. (Cl. 197-453) This invention relates to typewritingmachine attachments and more particularly to portable attachments designed to support duplicating ribbons for the production of multiple copies.

The most common method of producing multiple or carbon copies during the execution of an original paper on a typewriting machine is to employ separate pieces of carbon paper which are interleaved between the copy paper by the operator of the machine. In order to get away from this laborious and often messy procedure, particularly where the number of copies desired is not great, it has been proposed that a ribbon carbon made of either cloth or paper be utilized. But this too has presented difiiculties. Often elaborate means have had to be provided to hold such ribbons and even more elaborate means to anchor the holding means to the main frame or carriage of the typewriting machine. Even in the so-called portable attachments heretofore developed, a number of screws, legs, arms, and other miscellaneous brackets have had to be adjusted in order to fit a ribbon holding attachment to a standard typewriting machine.

In addition to these adjustments which are required for portable attachments representative of the prior art, they have generally shared with their non-detachable counterparts problems common to all ribbon duplicating attachments. One of these common problems relates principally to the means employed to separate adjacent pieces of paper as the pieces are advanced around the platen of an associated typewriting machine. An adjunct of this problem or perhaps, more accurately, one of the penalties to be suffered if the means employed are not appropriate to the end, is that the ribbon is dragged out of position. This had the effect of increasing the probability that the carbon copy will either be incomplete, smudged, or quite likely both. A connected problem, but one somewhat separate, is the likelihood of smudging the back of the original paper as well. The latter can occur in spite of provision being made to keep the ribbon feeding properly and to keep the. adjacent pieces of paper apart.

In the past, the principal proposals made to obviate these shortcomings have included the use of parallel wires extending above and below the impression or striking positions of the typeheads and parallel to the surface and longitudinal axis or" the platen. These have been less than satisfactory in most cases which, in turn, has led to additional means proposed to maintain the wires under constant tension, etc.

It is in the setting of this prior art relating to portable duplicating attachments and these not always satisfactory arrangements to guide papers, prevent disarrange ment of the duplicating ribbon, and preventing smudging of the back of the original that the present invention has significance. A truly portable duplicating attachment has been developed which will fit substantially all standard typewriting machines without preliminary adjustments. This invention constitutes an improvement over Patented Oct. 6, 1959 ice 2. a duplicating attachment disclosed and claimed in Patent 2,656,909, issued October 27, 1953, to N. S. McEwen.

This attachment combines novel means for separating original and copy papers and preventing smudging with enclosed replaceable ribbon assemblies. The combination provides a substantially universal. duplicating attachment which promotes clean copy work to a degree not heretofore realized in. the field.

A broad object of the invention, therefore, is to provide a simple, economical, and eflective duplicating attachment which overcomes one or more of the problems alluded to above.

.More particularly, objects of the invention are to simplify the positioning of a removable duplicating attachment on a typewriting machine; to positively maintain the attachment in. its proper position through cooperation with parts of the typewriting machine; to provide improved means for guiding paper and preventing the smudging thereof; to decrease the possibility of smudged copies resulting from an operator contacting the duplicating ribbon; to provide improved removable spool assemblies; and, to indicate visually to what extent the duplicating ribbon should be advanced when necessary.

A feature .of the invention pertains to means for supporting the duplicating attachment in proper juxtaposition to the platen of a typewritingmachine in such a manner as to eliminate preliminary adjustments. These means are supplemented by portions of spaced apart arms which coperate with the paper bail of the machine to maintain the duplicating attachment in its properly oriented position.

Still another feature of the invention is means cooperating with the spaced apart arms to guide original and copy papers and to prevent smudging of the back of the original paper during the execution of a copy with the duplicating attachment. 7

Yet another feature pertains 'to improved ribbon and spool assemblies wherein the operator is protected from contact with the ribbon during manipulation of the attachment or replacement of the duplicating ribbon. This latter feature also includes marking the duplicating ribbon at intervals approximating the length of the platen of the machine with which the attachment is employed. Such marking provides a ready indication of how far the ribbon need be rotated in order to present a fresh portion thereof for copy work, thus assuring a more uniform impressed copy.

More; particularly, the features of the instant invention relating to the spaced apart arms are characterized in that parts of the forward ends of the arms are appropriately slotted to guide the duplicating ribbon along a line adjacent the forward surface of the platen yet not in contact with it. Means are also provided on the arms. to support a separator which overlies and extends somewhat below the duplicating ribbon. This separator, is formed of a thin material which does not easily tear and which will deform to transfer a type impression from the type head to the duplicating ribbon and acts to seprate the paper as it advances around theplaten and to prevent the back of the original from coming into contact with the duplicating ribbon.

The feature relating to improved spool assemblies in the disclosed embodiment in somewhat more detail comprises a unitary spool cooperating with a shaft and guard member. The spool includes means to impart manual rotation to it as well as means to support and aflix a duplicating ribbon thereon, while the guard member in conjunction with a portion of the frame of the attachment substantially surround the spool member when it is mounted on one of the shafts provided for the purpose.

The overall result is an enclosed, easily replaceable spool assembly upon which is fixedly retained a duplicating ribbon in a simple and efiicient manner.

These and other objects and features of the present invention will be more readily understood when the following detailed description of the invention is read with reference to the drawings in which:

Figure 1 is a perspective of a part of a standard typewriting machine with the duplicating attachment properly positioned along the platen thereof;

Figure 2 is a perspective of the duplicating attachment shown in Figure 1 but removed from'the typewriting machine in order to more clearly illustrate its salient features; I I

Figure 3 is a partial end View taken along line 33 in Figure l with certain of the parts removed in order to more clearly show how the duplicating attachment cooperates with certain parts of the typewriting machine and original and copy paper;

Figure 4 is a partial plan view designed to show with minimum distortion the configuration of the ends of the spaced apart arms and the way in which they guide a duplicating ribbon and support the separator;

Figure 5 is an exploded view of one of the spool assemblies and the end of the duplicating attachment with which it is associated; and

Figure 6 is a perspective of a device which may cooperate with the bail to hold the attachment in place.

Referring more particularly to Figures 1 and 2, it can be seen that the duplicating attachment generally comprises a bar or frame member having upstanding bearing plates 21 aflixed to each end thereof. Also afiixed to each end of bar 20 is a support bracket 22 having a forwardly extending platen support arm 23 and a rearwardly extending paper rest support member 24. A spool assembly 25 is rotatably mounted on each bearing plate 21 with each end of aduplicating ribbon 26 attached to one of the spool assemblies 25 and supported along a line of type by the forwardmost ends of the support arms 23.

When the attachment is properly positioned upon a typewriting machine (as in Figure 1), the bar-member or frame 20 lies along a line substantially parallel to the longitudinal axis of the platen 2 and above and somewhat behind it. The frame 20 is supported in this position by the joint action of the paper rest support members 24 and platen support arms 23. The paper rest sup port members 24 are bent to rest upon the top edge of the paper rest or table 3 and the platen support arms 23 are bent downwardly to approximate the curvature of the platen 2. With the attachment so positioned, the arms 23 support the duplicating ribbon along a line of type and behind the type head guide 6, the ribbon vibrator 7, and the regular typewriter ribbon 8.

The paper bail 4 including paper holders 5 cooperates with the upper surfaces of the platen support arms 23 to firmly hold the duplicating attachment in its correct position during the operation of the typewriting machine to produce an original and carbon copy.

In the more detailed description of the attachment which follows, it is well to keep in mind that all references to directions relate to the typewriting machine with the attachment positioned thereon in accordance with Figure 1. For example, forwardly refers to that part of the attach ment which extends toward the front of the type- Writmg machine when the attachment is in situ on the machine. Similarly, rearwardly refers to the rear of the attachment in situ, and above or upwardly to the top of the attachment in situ. Reference to the left or right s1de of the attachment relates to respective sides of Figure 1 or the comparable parts of the attachment as orientated' therein with reference to the typewriting machine and an operator.

Referring in more detail to the duplicating attachment, per se, it w1ll be observed (Figure 2) that the frame 20 1s a flat member having an'upstanding right angle portron 31 WhlCh in cooperation with transverse braces 9;

- ribs 32 assures a rigid frame section. The bearing plates 21 are fixedly attached to each of the ends 33 of the frame 20 and at right angles to the longitudinal axis of the typewriter platen 2. The bearing plates 21 extend upwardly from frame ends 33 and the support brackets 22 are attached to them at. their lower surfaces. The frame member 20 is of suflicient length to dispose the bearing plates 21 and support brackets 22 adjacent the two ends of the platen 2. The distance between the arms 23, therefore, is somewhat greater than the width of the copy paper used.

As can best be seen in Figure 5, extending outwardly v at right angles from each bearing plate is a shaft 35 which is held firmly against its respective bearing plate 21 by a nut 36 threaded on the inner ends of the shafts (threads not shown), which shafts extend through apertures centrally located in each bearing plate 21. The shafts 35 are split as connoted at 37 to allow their diameters to be varied, e.g., by the insertion of a screw driver blade therein. This permits a friction fit to be maintained between the shafts 35 and their cooperating spool assemblies 25. A guard member 45 is retained against the outer surface of each bearing plate 21 and in cooperation with shaft 35 and the spool 38 (to be hereinafter described in detail) illustrates a novel type of spool assembly generally designated as 25.

In the disclosed embodiment of the present invention, the frame 20, member 31, ribs 32 and bearing plates 21 are formed as a unitary structure of a thermosetting resin, e.g. Bakelite, but it is apparent, of course, that these members could be fabricated in other ways and with other materials. Similarly, while support brackets 22 are formed of a flexible flat steel, there is no reason why they should not be formed diiferently. The particular structures as shown are only illustrative of one Way of fabrieating the parts of the present invention.

The support brackets 22 are held in position along the lower surfaces of ends 33 by screws 34 (Figure 3) and extend rearwardly and forwardly in planes substantially transverse to the longitudinal axis of the typewriter platen 2. The paper rest support member 24 curve upwardly and rearwardly, as shown most clearly in Figure 3, to rest on the upper surface of the paper rest or table 3 of the typewriting machine. The platen support arms 23 extend forwardly and downwardly with a radius of curvature approximating that of their coperating platen 2 in order to maintain the ribbon supporting ends thereof as flush with the platen 2 as is reasonably possible. The upper surfaces of the arms 23 intermediate the frame ends 33 and slots 50 are shaped to cooperate with the paper bail 4 of the typewriting machine when it is in place with the paper rollers 5 resting against a paper in the machine or the platen 2. This cooperation provides a positive means for holding the duplicating attachment properly juxtaposed to a machine. This same function could be accomplished in other ways, structurally speaking. For example, auxiliary circular holders (not shown) supportable by the paper bail 4 could be used tohold the platen arms 23 securely or, alternatively, rubber anchors similar to the one depicted in Figure 6 could be used. Each anchor 65 has a circular aperture 66 opened along one side so that it fits over the bail 4 of any conventional typewriting machine. An anchor 65 is mounted on the bail 4 to overlie each platen arm 23. Extending downwardly from each is a pair of feet 67 which bear against the upper surfaces of respective platen support arms 23.

The means integral with the lower end of each of the platen support arms 23 for positioning a duplicating ribbon 26 along a line substantially coincident with a line of type of the machine includes a longitudinal slot 50 which opens to the outer edge of its arm 23. The slot is of a reduced width at its outer edge due to a projection 51 (Figure 5) which acts to retain the ribbon in the slot during mgve pept. Located closer to the lower end of .chine.

each arm is a slot 52 which is cut at -a 45 degree angle to the longitudinal axis of the platen 2. These slots 52 lie in planes which intersect at substantially right angles and at .a point below the platen of the typewriting ma- A downwardly extending projection 54 on each .arm .23 cooperates with an outwardly extending one :53 to retain the ribbon .26 when it is once in position adjacent the slots 52. The slots 52 are arranged with respect to the normal positions of the arms 23 and the line of type of the machine so that the sduplicating ribbon 26 is supported along the platen 2 directly behind the regular ribbon 8 of the typewriting machine. That is to say, the lower and upper edges of ribbon 8 and duplicating ribbon 26 he in respective parallel planes which are in turn substantially parallel to said longitudinal axis of platen 2.

The projections 54 on the outer portions of arms 23 serve the further function of supporting the separator 56 alluded to earlier. In order to improve this function, a groove 55 is formed on these outer edges of the arms 23 (Figure 4).

The separator 56 is formed of a thin rectangularshaped, transparent material. Each end is formed with .a loop 57 in it and these loops slip over the projections 54 and engage grooves 55 to firmly hold the separator 56 between the spaced apart arms 23. Since the width of the groove 55 is made greater than the width of the duplicating ribbon '26, the separator 56 extends above and below the ribbon 26 when both are in position on the spaced apart arms 23. Then too, because the ribbon 26, when threaded on the duplicating attachment lies in a plane substantially coincident with the upper surface of the platen arms 23, as will be more fully explained hereafter, the separator 56 when supported between the arms 23 by projections 54 is in immediate contact with the ribbon.

Fairly wide latitude is permissible in choosing a ma- .terial to act as the separator 56. One material which has been found satisfactory is a Du Pont product sold under the trademark Milar. It is a thin cellulosic material easily impressionable but quite resistant to tearing. Naturally, it is not necessary that the material employed be one which is transparent nor need it be fiom the viscose family. Its important attribute must be a material thin enough to retain its impressionable characteristic and yet thick enough to provide an edge sturdy enough to act as a separator between an original and copy paper. The former is necessary, of course, to assure a clear carbon copy during the duplicating process.

As noted above, the spool assembly 25, which is most clearly shown in Figure 5, provides a compact ribbon assembly designed to permit easy replacement with a minimum of effort and messiness. The spool 38 comprises a circular knurled knob 39 having integrally attached to its inner surface a shaft 40 upon which is supported a ribbon sleeve 42. The integral unit of knob .39 and shaft 40 is apertured at 48 to provide means for receiving a shaft 35, as noted in more detail below.

One end of the ribbon 26 is first wrapped partially around sleeve 42 and firmly held in fixed relation thereto by spring clip 43 which is a half-circular detail constructed of spring steel. Once an end of the ribbon 26 is staked to the sleeve 42 by clip 43, the ribbon is wound around the sleeve. ,Staked is used herein in a broad sense to suggest any means by which the rela- V tive position of ribbon to sleeve is fixed.

The sleeve 42 is then fitted over shaft 4ii'on the spool 38. In order to fix or stake the relative position of the ribbon 26 with respect to the shaft 40 and hence, spool 38, a longitudinal key or projection 41 is formed on the shaft 40 to cooperate with a longitudinal keyway 44 formed in the sleeve 42. Thus, after the ribbon is wound on the sleeve and the sleeve fitted over the shaft 40,

rotation of the knob 39 controls the movement of the ribbon 26.

When a spool 38 receives one of the shafts 35, the course of tthe ribbon 26 lies in the transverse =plane, which plane substantially includes a cooperating support bracket 22. Hence, the ribbon 26 :can. be properly threaded along its associated aplaten support arm 23 and throu h slot 50.

The guard 45 is acup-type member with an aperture 46 through its bottom which allows the bottom 'of the guard 45 .to be afiixed flush to :the outer surface of its cooperating bearing ,plate .21.. It may be held in this position by glue, screws or other means. The lower .forward quadrant of the side 49 of the cup member 45 is excised to form aperture 47 through which the ribbon 26 can be threaded down along its cooperating arm 23. While theinstant cup .member is formed of a transparent Plexiglas .type of material, it could just as well be formed :of some opaque material, e g. Bakelite. A clear material, however, does have the advantage of permitting an operator .to determine on which spool most of the ribbon has collected.

With the spool 38 mounted on the shaft 35, the guard member 45 encloses the ribbon .26 and thereby prevents an operator from brushing against it. It is envisioned that replacement spools or .at least sleevcs'wouldbe available, ,possibly in pairs, so that when a replacement ribbon is needed an operator'could remove the old ribbon while holding the two spool knobs 38 and then thread -a new ribbon through the attachment, all without ever touching the ribbon itself. The ribbons can be marked with white lines 60 at intervals of approximately nine inches in order to visually indicate how far the ribbon should be advanced when one section becomes worn.

More particularly, in order to place a ribbon on the duplicating attachment, it is threaded from one of the sleeves 42 through the aperture 47 of one guard member 45, down along a platen support arm '23, through a slot 50, up and across diagonal surface 52 and, along a line of type to the other arm- 23, down and across the other diagonal surface 52, up through the other slot 50, along the other platen support arm 23, and through the aperture 47 of the other guard member 45 to the other sleeve 42.

After the duplicating attachment is properly threaded in accordance with the foregoing, it is ready to use. An original and copy paper, such as 9 and 1t) respectively (Figure 3), are fed into the typewriting machine in the usual way by placing them against the paper table 3 and rotating the platen 2 either by the carriage return lever 11 or the cylinder or platen knob 12. The paper bail 4' is lifted away from the platen 2 and the duplicating attachment is positioned on the typewriting machine in accordance with Figure 1. After the platen arms 23 are flush with the platen 2 and the rear support members 24 rest on the paper table 3, the paper bail 4 is returned to its operating position (adjacent the platen) thereby engaging portions of the arms 23 to hold the attachment firmly.

As the attachment is placed in position, the copy paper is directed behind the separator 56 and the duplicating ribbon 26 and the original paper to the front of them. The result, as viewed in cross-section is substantially that depicted in Figure 3. With this accomplished, the operator proceeds to execute an original and copy in the ordinary manner, e. g. by striking a key associated with exemplary typehead 13. Whenever the duplicating ribbon 26 is producing carbons too light, the operator rotates the knobs 39 simultaneously in opposite directions until the mark 60 at the left side of the attachment has moved to the right side and another mark 60 has appeared at the left side. Thereafter further copies may be made.

While only a few alternatives have been suggested 'to the disclosed embodiment of the present invention, which embodiment has been described in detail, it is to be understood that they do not exhaust the possibilities. All of the above-described arrangements are merely illustrative of the application of the principles of the invention. Numerous other arrangements may be devised by those skilled in the art without departing from the spirit and scope of the invention.

What is claimed is:

1. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon marked at intervals approximating the maximum travel of said machine, a bar adapted to be positioned above the platen of said typewriter and to lie along a line substantially parallel to the longitudinal axis of said platen, upstanding bearing plates attached to each end of said bar and lying in planes transverse to said axis, a shaft afiixed to each of said bearing plates and extending outwardly therefrom, spool assemblies rotatably mounted on said shafts and having the ends of said duplicating ribbon attached thereto, each of said spool assemblies including means to support a part of said duplicating ribbon and to manually impart rotation thereto, a guard member cooperating with'each bearing plate and spool assembly to prevent exposure of said duplicating ribbon, support brackets attached to each end of said bar to cooperate with the paper rest and platen of said machine, the portions of said brackets cooperating with said platen including support arms extending downwardly and toward the front of said machine to conform to the surface of the platen, each of said support arms including means at their free ends for cooperatively positioning said duplicating ribbon adjacent the platen along a line coincident with a line of type, said positioning means including means for guiding said ribbon along said line, means for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, said separator performing the dual function of separating said original and copy paper as they are advanced around the platen and of preventing the back of said original from becoming smudged by the duplicating ribbon.

2. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon, a bar adapted to be supported above and to lie along the platen of said typewriter, said bar' maintained there during operation of said typewriting machine, upstanding bearing plates attached to each end of said bar and lying in planes transverse to the longitudinal axis of said platen, a shaft afiixed to each of said bearing plates and extending outwardly therefrom, spool assemblies rotatably mounted on said shafts and having the ends of said duplicating ribbon attached thereto, each of said spool assemblies including means to support a part of said duplicating ribbon and to manually impart rotation thereto, a guard member cooperating with each bearing plate and spool assembly to prevent exposure of said duplicating ribbon, support brackets attached to each end of said bar to cooperate with the paper rest, platen and bail of said machine, the portions of said brackets cooperating with said platen and bail including support arms extending downwardly and toward the front of said machine to conform to the surface of the platen, each of said support arms including means at their free ends for cooperatively positioning said duplicating ribbon adjacent the platen along a line coincident with a line of type, said positioning means including means for guiding said ribbon along said line, means for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying andextending below said ribbon, said separator performing the dual function of separating said original and copy paperas they are advanced around the platen and of preventing the back 8 of said original from becoming smudged by the duplicating ribbon.

3. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon, abar adapted to be positioned above and to lie along the platen of said typewriter, enclosed spool assemblies rotatably mounted at the ends of said bar, support brackets attached to each end of said bar to cooperate with the paper rest and platen of said machine to properly position said bar, the portions of said brackets cooperating with said platen including support arms extending downwardly and toward the front of said machine to conform to the supporting platen, each of said support arms including means at their free ends for cooperativeiy positioning said duplicating ribbon adjacent the platen along a line coincident with a line of type, said positioning means including means for guiding said ribbon along said line, means for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, said separator performing the dual function of separating said original and carbon copy paper as they are advanced around the platen and of preventing the back of said original from becoming smudged by the duplicating ribbon, and said duplicating ribbon affixed at each end to one of said spool assemblies and cooperating with said positioning means.

4. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a frame member, means including forwardly extending spaced apart arms and adapted to cooperate with the platen and paper rest of said typewriting machine to position said frame member adjacent said machine, means including the paper bail of said machine and parts of said spaced apart arms to positively maintain said attachment in position, ribbon spool assemblies rotatably mounted at the ends of said frame member, a duplicating ribbon having its ends attached on said spool assemblies and extending between said arms along a line of type, and means attached to said arms and overlying said ribbon to separate said original and said copy as the platen is rotated and to prevent said duplicating ribbon from smudging the back of said original.

5. A duplicating attachment in accordance with claim 4 wherein said means to positively maintain said attachment in position further includes a pair of anchors mountable on the paper bail of said typewriting machine and adapted to bear against said spaced apart arms when the attachment is positioned adjacent said machine.

6. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon, a bar adapted to be positioned above the platen of said typewriter and to lie along a line substantially parallel to the longitudinal axis of said platen, enclosed spool assemblies rotatably mounted at the ends of said bar, support brackets attached to each end of said bar transverse to said longitudinal axis, each of which includes a support member and a support arm, said support members extending upward and toward the rear of said typewriting machine to cooperate with the paper rest of said machine and said support arms extending downwardly and toward the front of said machine to conform to the supporting platen, each of said support arms including means at their free ends for cooperatively positioning said duplicating ribbon adjacent the platen along a line coincident with a line of type, said positioning means including means for guiding said ribbon along said line, means for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, said separator performing the dual function of separating said original and carbon copy paper as they are advanced hem, and said duplicating ribbon affixed at each end to one .of said spool assemblies and cooperating with said positioningmeans.

7. A duplicating attachment for obtaining a carbon copy during :the production rof :an original paper on a :typewriti-ng machine comprising, in combination, a dllplicatingribbon, aibar adapted :torbe positioned above and vlie ,along ,the platen of said typewriter, said duplicating attachment being adapted to be held in position by the paper hail of saidtypewriting machine, enclosed spool assemblies ,rotatablymountedat ithe ends ,of said bar and having the ,ends of said duplicating ribbon attached thereto, support brackets attached ;:to each end of said ,bar and each including a support member and a support arm, said support members extending upward and toward the rear of said typewriting (machine to cooperate :with :the paper rest thereof and said support arms extending downwardly and toward the front of said machine to conform to the surface of the platen, each of said support arms including means at their free ends for cooperatively positioning said duplicating ribbon adjacent the platen along a line coincident with a line of type, said positioning means including means for guiding said ribbon along said line, means for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, said separator performing the dual function of separating said original and carbon copy paper as they are advanced around the platen and of preventing the back of said original from becoming smudged by the duplicating ribbon.

8. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon, a rigid bar adapted to be positioned above the platen of said typewriter and to lie along a line substantially parallel to :the longitudinal axis of said platen, upstanding bearing plates affixed to each end of said ,bar and lying in planes transverse to said axis, a shaft affixed ,to each of said hearing plates and extending outwardly therefrom, :Spool assemblies rotatably mounted on said shafts, each of said spool assemblies including means Which support one end of said duplicating ribbon and means which may be manually moved to impart rotation to [the ribbon, a guard member cooperating with each bearing plate and spool assembly to prevent exposure of said duplicating ribbon, support brackets attaehed L each end of said bar and each including a support member cooperative with the paper rest of said typewritingmachiue and a support arm cooperative with the platen of said typewriting machine, said support members extending upward and toward the rear of said typewriting machine and said support arms extending downwardly and toward the front of said machine to cgrrform to the surface of the platen, each of said support arms including means at their free ends for coop- ,eratiuely positioning said duplicating ribbon adjacent the platen along .a line coincident with a line of type, said POSitiQfling means including means for guiding said ribbon along said line, ,rneans for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, said separator performing the dual function of separating said original and copy paper as they are advanced around the platen and of preventing the back :of said original from becoming smudged by the duplicating ribbon.

9. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting, machine comprising: in combination, a duplica ing ribbon, a bar adapted to be supported and to lie along the platen of said typewriting machine, upstanding bearing plates fixedly attached to each end of said bar and lying in planes transverse to the longitudinal axis 10f said platen, a shaft affixed to each of said bearing plates and extending outwardly therefrom at right angles spool assemblies apertured to receive said shafts, adjustable means integral with said shafts to obtain friction fits !for said assemblies, reach of .said spoolassemblies includinga spool havingan outwardly disposed part for manually imparting rotation thereto and inwardly disposed means for supporting said duplicating ribbon to rotate with said spool, an ,apertured cup-type guard member affixed to theouter surface of each bearing plate to substantially surround said duplicating ribbon when said spool assemblies are mounted on said shafts, surfaces on the forwardly disposed sides of each cup member defining a cut-out to permit said duplicating ribbon to pass through, support brackets attached to each end of said bar to cooperate with the paper rest and platen of said machine, the portions of said brackets cooperating with said platen including support arms extending downwardly and toward the front of said machine to conform to the surface of the platen, each of said support arms including means at their free ends for cooperatively positioning said duplicating ribbon adjacent the platen along a line coincident with a line of .type, said positioning means including means for guiding :said ribbon along said line, means for maintaining a separation between .the ,ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, and said duplicating ribbon affixed at each end :to tone of said spools and threaded through said cut-outs of said cup-type guards to cooperate with said positioning means.

10. A duplicating attachment for obtaining a carbon copy during the productionof an original paper on a typewriting machine comprising, in combination, a duplicating ribbon marked at nine inch intervals, a rigid bar adapted to be positioned above the platen of said typewriter and .to lie along a line substantially parallel to thelongitudinal axis of said platen, upstanding bearing plates fixedly attached to each end of said bar and lying in planes transverse .to said longitudinal axis, a shaft afiixed to each of said bearing-plates and extending outwardly therefrom at right angles, spool assemblies apertured to receiveeach of said shafts, adjustable means integral with said shafts to :obtain friction fits for said assemblies, .each of said spool assemblies including a spool having an outwardly disposed pant for manually imprating rotation thereto and inwardly disposed means for supporting said duplicating ribbon to rotate with said spool, an apertured cup-type guard member afiixed to the outer surface of each bearing plate to substantially surround said duplicating ribbon when said spool assemblies are mounted on said shafts, surfaces on the forwardly disposed sides of each cup member defining a cut-out .to permit said duplicating ribbon to pass :through, support brackets attached to each end of said bar and each including a support member cooperative with the paper rest of said typewriting machine and a platen suppontarmcooperat-ive with the platen of said typewriting machine, said support members extending upward and toward the rear of said typewriti-ng machine and said support arms extending downwardly and toward the front of said machine, each of said support arms including means at their free ends for cooperatively positioning said duplicating ribbon adjacent the platen along a line coincident with a line of type, said positioning means including means for guiding said ribbon along said line, means for maintaining a separation between the ribbon and the platen or copy paper, and means for maintaining a separator overlying and extending below said ribbon, and said duplicating ribbon afiixed at each end to one of said spools and threaded through saidcut-outs of said cup-type guards to cooperate with said positioning means.

11. ,A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon, a bar adapted to be positioned above the platen of saidtypewriting machine and to lie along a line substantially parallel to the longitudinal axis of said platen, enclosed spool assemblies rotatably mounted at the ends of said bar, support brackets attached to each end of said bar at substantially right angles to said longitudinal axis and including a support member cooperative with the paper rest of said typewriting machine and a support arm cooperative with said platen, said support members extending curvilinearly upward and toward the rear of said typewriting machine and said support arms extending downwardly and toward the front of said machine with their forward free ends bent to approximate the curvature of the platen; each of said platen support arms including means for cooperatively positioning said duplicating ribbon adjacent but not in contact with said platen and along a line coincident with a line of type, said positioning means including a longitudinally oriented slot opening to the outer edge of each of the respective arms, a surface at the lower end of each arm cut at an angle of 45 degrees to the longitudinal axis, these surfaces oriented with respect to each other such that planes including them would intersect below the duplicating attachment when properly positioned on a typewriting machine, and downwardly extending vertical projections and outwardly extending horizontal projections adjacent respective ends of the cut surfaces on each of said arms, said vertical projections further proportioned to maintain a translucent separator formed of a celluloid material overlying and extending below said ribbon, said separator performing the dual function of separating said original and carbon copy paper as they are advanced around the platen and of preventing the back of said original from becoming smudged by the duplicating ribbon, said duplicating ribbon aflixed at each end to one of said spool assemblies and threaded downwardly through said slots and upwardly across said cut surfaces.

12. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon, a rigd bar adapted to be positioned above and somewhat behind the platen of said typewriter and to lie along a line substantially parallel to the longitudinal axis of said platen, upstanding bearing plates attached to each end of said bar and lying in planes transverse to said axis, a shaft affixed to each of said bearing plates and extending outwardly therefrom, spool assemblies rotatably mounted on said shafts, each of said spool assemblies including means to support said duplicating ribbon and to manually impart rotation thereto, a guard member cooperating with each bearing plate and spool assembly to prevent exposure of said duplicating ribbon, support brackets attached to each end of said bar at substantially right angles to said longitudinal axis and including a support member cooperative with the paper rest of said typewriting machine and a support arm cooperative with said platen, said support members extending curvilinearly upward and toward the rear of said typewriting machine and said support arms extending downwardly and toward the front of said machine and bent to approximate the curvature of the platen; each of said sup port arms including means for cooperatively positioning said duplicating ribbon adjacent but not in contact with said platen and along a line coincident with a line of type, said positioning means including a longitudinally oriented slot opening to the outer edge of each of the respective arms and a surface at the lower end of each arm cut at an angle of 45 degrees to the longitudinal axis, and means to support a translucent separator formed of a thin celluloid material overlying and extending below said duplicating ribbon, said separator performing the dual function of separating said original and carbon copy as they are advanced around the platen and of preventing 12 the back of said original from becoming smudged by the duplicating ribbon, said duplicating ribbon aflixed at each 'end to one of said spool assemblies and threaded downwardly through said slots and upwardly across said out surfaces, and means to retain said duplicating ribbon in said slots and across said out surfaces.

13. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a duplicating ribbon marked at nine inch intervals, two support brackets, a rigid bar adapted to be positioned above the platen of said typewriter by said support brackets and to be firmly held there by means including the paper bail of said typewriting machine cooperating with portions of said support brackets, said bar lying along a line substantially parallel to the longitudinal axis of said platen, unstanding bearing plates fixedly attached to each end of said bar and lying in planes transverse to said longitudinal axis, a shaft affixed to each of said bearing plates and extending outwardly therefrom at right angles, spool assemblies apertured to receive each of said shafts, adjustable means integral with said shafts to obtain friction fits for said assemblies, each of said spool assemblies including a spool having an outwardly disposed part for manually imparting rotation thereto and inwardly disposed means for supporting said duplicating ribbon to rotate with said spool, and apertured cup-type guard member affixed to the outer surface of each bearing plate to sub: stantially surround said duplicating ribbon when said assemblies are mounted on said shafts, surfaces on the forwardly disposed sides of each cup member defining a cut-out to permit said duplicating ribbon to pass through, said support brackets being attached to each end of said bar at substantially right angles to said longitudinal axis and each including a support member cooperative with the paper rest of said typewriting machine and a support arm cooperative with said platen, said support members extending curvilinearly upward and toward the rear of said typewriting machine and said support arms extending downwardly and toward the front of said machine and formed to cooperate with said paper bail and to approximate the curvature of the supporting platen, each of said support arms including means for cooperatively positioning said duplicating ribbon adjacent but not in contact with said platen and along a line coincident with a line of type, said positioning means including a longitudinally oriented slot opening to the outer edge of each of the respective arms, a surface at the lower end of each arm cut at an angle of 45 degrees to the longitudinal axis, these surfaces oriented with respect to each other such that planes including them would intersect below the duplicating attachment when properly positioned on a typewriting machine, and downwardly extending vertical projections and outwardly extending horizontal projections adjacent respective ends of the cut surfaces on each of said arms, said vertical projections further proportioned to maintain a translucent separator formed of a thin, rectangularshaped celluloid material overlying and extending below said ribbon, said separator performing the dual function of separating said original and carbon copy as they are advanced around the platen and of preventing the back of said original from becoming smudged by the duplicating ribbon, said duplicating ribbon afi'ixed at each end to one of said spools and threaded through said cut-outs on said cup-type guards, downwardly through said slots and upwardly across said cut surfaces.

14. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting machine comprising, in combination, a frame having spaced apart arms, means adapted to position said frame adjacent said typewriting machine, a pair of spool assemblies, means including shafts associated with said frame to support said spool assemblies, each of said spool assemblies apertured for rotatable support on said shafts and including a spool having an outwardly disposed knob for manually imparting rotation thereto and inwardly disposed means for supporting a duplicating ribbon to rotate with said spool, guard memzers which substantially surround said ribbon supporting means on said spools, and a duplicating ribbon having its ends attached on said spools and extending between said arms along a line of type, said ribbon supporting means comprising first means to support said duplicating ribbon, second means associated with said knob to support said first means, and other means cooperating with said first and second means to maintain a fixed relation between said ribbon and said knob.

15. A duplicating attachment for obtaining a carbon copy during the production of an original paper on a typewriting maching comprising, in combination, a frame having spaced apart arms, means adapted to position said frame adjacent said typewriting machine, a pair of spool assemblies, means including shafts associated with said frame to support said spool assemblies, each of said spool assemblies apertured for rotatable support on said shafts and including a spool having an outwardly disposed knob for manually imparting rotation thereto and inwardly disposed means for supporting a duplicating ribbon to rotate with said spool, guard members which substantially surround said ribbon supporting means on said spools, and a duplicating ribbon having its ends attached on said spools and extending between said arms along a line of type, said ribbon supporting means comprising first means around which is wound said duplicating ribbon, means for staking one end of said ribbon to said first means, second means associated with said knob to support said first means, and means associated with said first and second means to maintain said first means in a fixed relation to said knob.

16. A duplicating attachment in accordance with claim 15 wherein said first means comprises a circular sleeve having a keyway formed therein, said staking means is a circular-shaped spring clipped on said sleeve, and said second means is a shaft integral with said knob and having a key formed along its outer surface to cooperate with said keyway to support said sleeve in an angularly fixed position with respect thereto.

References Cited in the file of this patent UNITED STATES PATENTS 2,092,780 Sacerdote Sept. 14, 1937 2,656,909 McEwen Oct. 27,1953 2,667,257 Hurtado Jan. 26, 1 954

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