US2700933A - Antistreak means for duplicators - Google Patents

Description

Feb. 1, 1955 c, WHITE 2,7UU,933

ANTISTREAK MEANS FOR DUPLICATORS Filed April 1, 1953 INVENTOR 7/70/1445 C l/H/TE M MW United States Patent ANTISTREAK MEANS FOR DUPLICATORS Thomas C. White, Memphis, Tenn.

Application April 1, 1953, Serial No. 346,143

3 Claims. (Cl. 101-422) This invention relates to an anti-streak means for duplicators. More particularly it relates to a clamp-on attachment for applying ink-repelling fluid to the retainer roller of duplicating machines to prevent streaking of the printed copy.

Specifically, the invention relates to a pad carried by an arm pivoted to a friction-type clamp which is engageable on the roller carrying yoke of the duplicator and positioned thereby to engage the retainer roller for applying ink-repelling liquid thereto.

Duplicator machines conventionally employ retainer rollers and ejector rollers beneath which the freshly printed sheets pass to discharge, for insuring proper handling of the printed sheets. While it is obvious that the retainer (or hold-down) rollers and also the ejector rollers would operate more satisfactorily if they could be moved inwardly to engage the printed sheet approximately midway between its center and its edge so as to equalize the areas of engagement, in the duplicators of the prior art and on most printing jobs this could not be done since the rollers, particularly the retainer rollers, pick up ink from the freshly printed sheets and transmit the ink to following surfaces so as to thereby streak or smudge succeeding sheets. Thus it has been necessary for the operator to remember and to painstakingly laterally adjust the rollers for, each printing job in order that they would engage the sheets on unprinted areas generally along margins, closely adjacent the edge of the printed portions in order that the effectiveness of the rollers would be as great as could be obtained under the circumstances, while attempting to avoid roller contact with ink, producing a generally unsatisfactory but unavoidable compromise at best. Even then it frequently happens that a sheet would become disalined and transfer ink to the rollers, resulting in streaking or smudging of the succeeding impressions, and in addition many printing jobs are from edge to edge leaving no uninked areas for roller contact.

The present invention not only prevents such accidental streaking, but also permits maintaining the rollers in more effective retaining and ejecting positions without the streaking that such positioning would heretofore produce, and without requiring time-consuming adjustments.

It is a principal object of this invention to provide a device for applying ink-repellant liquid to the retainer rollers of a duplicator.

It is another object to provide a device of this type which is of simple, inexpensive and easily installable construction.

It is the general object of this invention to increase and to improve the quantity and quality of duplicator output.

The means by which the foregoing and other objects of this invention are accomplished and the manner of their accomplishment will readily be understood from the following specification upon reference to the accompanying drawings, in which:

Fig. 1 is an elevational view of the discharge end of a duplicator embodying the invention.

Fig. 2 is a fragmentary elevational view in section taken on the line II-II of Fig. 1.

Fig. 3 is a fragmentary elevational view taken on the line III-III of Fig. 2.

Fig. 4 is an elevational view of the yoke-carried rollers and the repellant applicator attached thereto, in section taken on the line IV-IV of Fig. 3.

Fig. 5 is a perspective view of the anti-streak attachment per se.

Referring now to the drawings in which the various 2,700,933 Patented Feb. 1, 1955 parts are indicated by numerals, in Figs. 1 and 2, the numeral 11 generally designates a typical duplicating machine having a cabinet-type housing 13. At the upper left of Fig. 1 can be seen the top of the fountain or reservoir 15 for the repellant solution. Below reservoir 15 is the cover 17 for the ink distributing and applying rollers 19 showing below the ink pan or trough 21. Fan 21 carries a series of ink application adjustment knobs 23. Hand wheels 25 are for the manual rotation of the blanket cylinder, and 27 designates one of the operation control arms. Parts 29 are the side panels of the inkingroller casing, and are attached to housing 13 as by screws A tray or basket 33 for receiving the printed sheets 35 is attached to housing 13 by screw 36 (Fig. 2). Tray 33 has a pair of upstanding stops 37 between which the flexible sheet-depressing metallic strap 39 extends, the strap 39 being held in place by a cross bar 41 (Fig. 1) above tray 33 and extending across the path of the ejected printed sheets in the (grounded) brush-like metal-bristled static-eliminator 43, over which the paper passes from the ejector mechanism with which the device of this invention cooperates.

Numeral 45 designates the pressure cylinder between which and the blanket-carrying cylinder (not shown) the sheet of paper 47 is pressed in transferring thereto the impression made on the blanket from "mastercarrying cylinder (also not shown) in well known manner. Pressure cylinder 45, being power-driven along with the other two cylinders, thus can be considered to he the first member of the ejecting mechanism. Cooperating with cylinder 45 are a pair of retainer rollers 49 (Figs. 2, 3 and 4) adapted to bear lightly against the sheet 47 to hold or retam it against cylinder 45 for the proper ejection. Two pairs of pointed strippers 51 remove the paper sheet 47 from cylinder 45 and guide it between the lower ejector roll 53 and the upper e ector rollers 55, from and by which the sheet is guided over static eliminator 43 and into the tray or basket 33, as previously described.

The retainer or hold-down rollers 49 and the upper e ector rollers are mounted in a yoke 56 formed of two parallel flat metallic bars 57, connected medially by a spacer 59. Yokes 56 are pivotally mounted on a shaft 61, which also serves as the shaft for rollers 49, and which is parallel to the axis of rotation of pressure cylinder 47. Yokes 56 and the rollers 49 and 55 carried thereby are laterally slidably adjustable along shaft 61 so as to place said rollers in positions for best performance.

It is to avoid streaking or smudging of the printed sheets, either when the rollers accidentally contact inked portions or the sheet, or are deliberately located above such portions for better ejection or to avoid time-consuming ad ustments, that the present invention was conceived and developed.

The device for applying ink-repellents comprises a clamp 63 conveniently formed of sheet metal bent into a generally inverted U-shape. The legs 65 of the U are preferably vertically slit to form fingers 65A that can be alternately bent, as shown, for frictional downward engagement over the opposite surfaces of the spaced side members 57 of the yokes 56. The top portion 67 of the U-shaped clamp 63 is preferably provided with tabs 65B which may be upstruck therefrom to form bearing posts which are bored to form journals for receiving and rotatably supporting pins or trunnions 67 by which the channel-bar arm 69 is pivotally attached to said clamp 63.

Arm 69 carries in the forward end of its downwardly open channel a pad 71 of any suitable liquid-absorbent material. Pad 71 is preferably constantly supplied with an ink-repelling liquid by a flexible conduit 73 connected at one end to the pad by a connecting tube 75 set in an aperture in arm 69, and at its other end to a reservoir 77 (Fig. 2) attached in any desired and suitable manner to the duplicating machine, or if desired to a reservoir supplying repellant to another part of the apparatus.

In the use of the device, clamp 63 is positioned so that the finger 65A of legs 65 clampingly engage against the opposite faces of bars 57, thus firmly but removably mounting the device on yoke 56. Channel-carried pad 71 is positioned to rest in contact with the upper portion of the periphery of hold-down roller 49 and as the roller is revolved, ink repellant solution is delivered to the periphery of the roller, thus treating same so as to repel any ink from attraction to the roller and thus effectively prevent the streaking and smudging heretofore caused thereby.

Thus it will be seen that I have provided a simple, economical, easily attachable, yet highly effective and practical device for preventing work spoilage and/or time-consuming roller adjustments in a duplicating machine.

I claim:

1. For use with a duplicating machine having ejecting rolls and at least one pair of longitudinally alined rollers cooperating therewith to press printed sheets against said rolls for ejection thereby, said rollers being mounted between a pair of bars forming a yoke-like support therefor; a clamp member adapted to engage at least one of said bars, at least one arm attached to said clamp, a liquid applicator carried by said arm, said arm being adapted to hold said applicator in liquidtransfer relationship to one of said rollers, whereby the same can roll over printed impressions without streaking or smudging the same when ink-repelling liquid is added to said applicator, said clamp being formed of a wide strip of sheet metal, bent to form an inverted U-shaped clamp, the sides of said clamp being slit to form fingers, said fingers being laterally ofiset so as to embrace opposite sides of said yoke forming bars to frictionally affix said clamp to said bars.

2. An attachment for applying ink-repelling liquid to the retainer rollers of a duplicating machine, comprising a wide metallic strap bent into inverted U-shape, the legs of which are adapted for clamping engagement with spaced parallel bars of the type used to support retainer rollers in a duplicating machine, the bight portion of said U-shaped strap having tabs upstruck therefrom to form facing bearing plates, a horizontally disposed arm between said plates, pins on said arm adapted to be journalled in alined apertures in said plates, whereby said arm is pivotally supported on said clamp for rotation about a horizontal axis, and an applicator pad attached to said arm adjacent its free end.

3. An attachment according to claim 2, the legs of said clamp being slit to form vertically disposed fingers, said fingers being bent to embrace opposite sides of said bars for frictionally attaching said clamp thereto.

References Cited in the file of this patent UNITED STATES PATENTS 423,660 Brooks Mar. 18, 1890 438,342 Brooks Oct. 14, 1890 2,465,160 Levenhagen et al. Mar. 22, 1949 2,647,462 Dell Aug. 4, 1953

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