US2394657A - Apparatus for preventing offset - Google Patents

Description

Feb. 12, 1946. BEREGH 2,394,657

APPARATUS FOR PREVENTING OFFSET File d Feb. 4, 1942 2 Sheets-Sheet 1 v I INVENTOR: 35 'THEIODVORE; J 'BEREGH BY I. #Q 6 7ATTQRNEYS Feb. 12, 1946. T. J. BEREGH APPARATUS FOR PREVENTING OFFSET FiIed Feb. 4, 1942 2 Sheets-Sheet 2 INVENTOR: THEODORE J BCREGH TTORNEYS.

Patented Feb. 12, 1946 APPARATUS FOR PREVENTING OFFSET Theodore John Beregh, Patchogue, N. 2.. assignor of fifty-one one-hundredths to Frank V. Mc- Mahon, New York, N. Y., as trustee; Isabelle Beregh Moflatt, administratrix of said Theodore John Beregh, deceased, assignor to Jean D. Bercgh, Orange, N. J.

Application February 4, 1942, Serial No. 429,452

Claims.

This invention relates to new and useful improvements in the art of printing and relates more particularly to improvements in apparatus for opposing offset in printing.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof and in which like numbers refer to like parts throughout the several views, illustrate a preferred embodiment o1 this invention, and together with the description, serve to explain the principles of the invention.

Of the accompanying drawings:

Fig. 1 is a view in vertical section, with parts in elevation, taken along the line I-l of Fig. 3,

of an anti-offset and static-eliminating device constituting a preferred embodiment of this invention, and showing the general arrangement of the mechanical and electrical mechanism for effecting the delivery of powdered material upon the printed surface of a moving sheet;

Fig. 2 is a view in elevation with parts in section of one end of the device of Fig. 1 showing its driving motor;

Fig. 3 is a view in section, with parts in plan, of the device of Fig. 1 taken along the line 3-3 thereof and showing details of the powder delivery mechanism; and, I

Fig. 4 is a partly diagrammatic view of the electrical system of the device of Fig. 1.

Objects of the present invention are: to provide a novel and improved apparatus for treating a freshly printed sheet or web to the end that sheets so treated may be stacked upon each other without creating offset impressions of the printed matter; to provide a novel and improved apparatus for dusting the printed surface of freshly printed sheets which will avoid the dissemination of harmful quantities of dust in the surrounding atmosphere; to provide an apparatus for dusting freshly printed sheets as they are delivered, from a printing press and for eliminating the static charge acquired by the sheets during the printing operation; and, to provide a simple, compact apparatus of the nature aforesr id which is adapted for use on large and small presses.

Another object of this invention is to provide a new and improved apparatus for powder-ing sheet materialwhile in transit from one operation to another which will minimize the usual health hazards, atmospheric contamination and soiling of equipment ancillary to the performance of such an operation.

Referring now in detail to the embodiment of the invention illustrated by way of example inthe accompanying drawings, a feed member I is journalled, at either end in bearings 2 and 3 in a gear housing 4 and wall member 5, respectively. The feed member is adapted to be rotated at a relatively low R. P. M. by a suitable prime-mover. As here embodied, the feed member I is of hollow cylindrical construction and is provided with internal fittings 6 and 'l'from which extend shafts 8 and 9, respectively, journalled in the bearings 1 2 and 3, respectively.

The prime-mover, as embodied, may be electrically or fluid-pressure op rated and, as here embodied, comprises a fluid current motor having a high speed toothed turbine wheel ll joumalled for rotation upon a shaft ll which is fixed in the gear housing 4 and extends through a removable cover plate l2.

The gear housing 4 encloses a reduction gear train, generally designated by the numeral 13, interconnecting the turbine wheel Ill and the shaft 8 and functioning to impart the desired angular velocity to the feed member I from the turbine wheel.

The turbine wheel Ill is adapted to be driven by a gaseous fluid medium supplied thereto under suitable pressure. As embodied, air under pressure is supplied in regulable amounts to the wheel from a source (not shown). As here embodied, the wheel in is encased in a housing l4 which is secured to the cover plate l2 and to the housing 4 by screws IS. The housing is provided with an orifice l6 from which the working fluid supplied thereto under pressure through a passage l1 flows against the wheel Ill so as to impart motion thereto. A needle valve I8 is threadedly received in the passage l'l for controlling the air flow and, in consequence, the turbine speed. The working fluid is discharged from the housing through the discharge port l9.

The end plate 5 and the gear housing 4 are held in fixed spaced relation to each Other by a pair of structural members 25 to which the gear housing and end plate are removably secured by screws 26.

A pair of wall members 2'! form with the feed member I, the end plate 5 and gear housing 4,

- jacent the stream of powder particles.

a storage vessel which is adapted to contain a suitable absorptive agent in a dry finely-divided state, such as P wdered starch, for example. The presence of such a material is indicated in Fig. 1. As embodied, the wall members 21 are fixedly secured at one end, and at the other end yieldingly engage the rotary feed member I throughout its length with sufilcient pressure to retain the absorptive powder within the vessel while the feed member is at rest, but with insufilcient pressure to prevent the eduction, upon rotation of the feed member, in the direction indicated, of a thin stream of powder through the discharge orifice formedbetween one of the wall members and the downwardly moving side of the .feed member. As here embodied, the wall members 21 are of flexible material, preferably metal, and are coextensive in length with the feed member I. Each is firmly secured at its upper end between one of the spacing members 25 and a fastening strip 28 by means of screws 29. The lower end of each of the members 21 carries on its inner face a facing 30 of felt, or other suitable compressible fibrous material, which bears against the surface of the feed member I with suflicient pressure to prevent the escape of powder between the engazed surfaces while the feed member I is at rest. Closure of the vessel is completed by a removable cover member 3| whose lateral depending flanges snugly engage the spacing members 25.

Means are provided for projecting a gentle stream of gaseous fiuid medium downwardly ad- As embodied, the projecting means is supplied with air in regulable' quantities from any suitable source. As here embodied, a conduit'32 provided with a line of discharge orifices 33 is snugly supported at either end in recesses 34 and 35, in the end plate and gear housing 4, respectively.

The recess 34 communicates through a passage 36 in the gear housing 4 with the passage I! so that the air discharge rate from the discharge orifices 33 will be in direct proportion to the rotational speed of the turbine wheel III as that is established by manipulation of the needle valv'e I3.

The conduit 32 parallels the feedmember I throughout its length and, though snugly fitted in the recesses 34 and 35, is angularly'adjustable so that the air stream emitted may be caused to impinge more or less directly upon the descending powder particles unti1 the setting, which experience determines is most favorable. has been attained. I

The, curtain of powder particles educted from the storage vessel by rotation of the feed member I descends through an ionizing zone to the subjacent moving web Or sheet. As embodied, a 1

gas-filled tube energized from a source of high potential is positioned in the path of the descending stream of powder particles. As here embodied, a mercury-vapor tube 31 is supported intermediate its ends, in contiguous relation to the feed member I and slightly below the discharge orifice formed between the wall member 21 and the feed member I, upon a pair of flanged U- shaped brackets 38 respectively removably secured to the spacing members 25 by screws 39. Each bracket is formed with a recess 40 in which the tube is seated. The tube 3'! is generally L- shaped, as is indicated more particularly in Fig. 4, and its terminal end is connected by a cable 4| to a source of high potential, preferably an aitemating E. M. F. The tube end is preferablV enclosed in a suitable terminal and cable fitting, such as the fitting 42, generally indicated in Fig. 1, which is preferably removably secured to the end plate 5 by screws (not shown) or in any other 5 convenient manner.

The device is supported above and in closely spaced relation to the press structure 43 across which the freshly printed sheet or web 44 is moved in the direction indicated and in a known fashion by means of suitable conveying mechanism (not shown). The embodied supporting structure maintains the device in the desired vertical and horizontal relationship to the sublacent moving web 44 and may be secured to the press structure or separate therefrom, as the situation warrants.

As here embodied, the end plate 5 and gear housing 4 are provided with pairs of laterally extending internally threaded lugs 45 by which the device is secured to suitable supporting elements such as the upright member 46, by means of screws 41 or other suitable fastening devices.

The cable 4| connects the tube 31 with one terminal of a secondary winding S of a step-up transformer 43 whose primary winding P is connected by leads 49' and 50 to a source of low potential varying E. M. F. such as the A. C. generatoril.

The secondary-winding of the transformer and the press structure 43 are connected by leads 52 and 53, respectively, to a common ground as shown.

Operation of the device is as follows: the cover member 3| is removed and the vessel is supplied with powdered starch, for example. Assuming the web 43 to be moving in the direction indicated, the valve I8 is opened and air under pressure flows through the passages 11 and 36 to the turbine rotor I0 and conduit 32. The feed member I is dri en in a counter-clockwise direction, as viewed ating through the reducing gear train, I3.

As the feed member I slowly rotates, at a rate proportioned to the linear rate of travel of the freshly printed web 44, its downwardly moving side eflects a continuous eduction of powder particles from the variable orifice between it and the flexibly mounted wall member 21.

The descending curtain of powder particles is deflected in its course by the gas tube 31 which is energized by the transformer 48 and functions to alter the electrical characteristics of the particles in such fashion that they are, in consequence, attracted toward the grounded structure 43.

The air stream which issues from the orifices 33 downwardly toward the web 44 is also similarly acted upon by the gas tube 31, and assists in sweeping the descendingpcwder particles directly to the freshly printed surface of the 0 sheet or web 44.

The freshly printed surface is thus treated with the powder which is deposited thereon and forms a coating effective to prevent smudging or offset of the printed impressions when the sheets are stacked upon each other. Furthermore, the coating material is conveyed expeditiously and directly from the storage vessel to the surface to be coated with minimum loss of the total amount of coating material educted from the vessel. In consequence, dissemination of finely divided coating material into the atmosphere is minimized, health hazards are effectively reduced and deposition of an objectionable powder upon the surfaces of machinery andequipment is avoided.

Fig. 1, by the wheel III oper- The invention in its broader aspects is not limited to the speciflc mechanisms shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

I claim:

I. Web treating apparatus comprising in combination. means forming a ground electrode/for supporting a moving freshly printed surface; means for depositing finely divided absorptive material in a continuous stream in the space above said supporting means; a gas tube electrode in said space in the path of said stream; means for connecting a source of high potential with said electrodes; and, means for discharging a stream of gaseous fluid downwardly in said space alongside said gas tube electrode and in position to impinge directlysm the descending material particles directing said particles onto said surface.

2. Web treating apparatus comprising in coinbination means forming a grounded electrode for supporting a moving freshly printed surface; means for depositing finely divided absorptive material in a continuous stream in the space above said electrode, said means comprising a rotary feed member, a fluid current motor for rotating said member and a valve for controlling the flow of working fluid to said motor; a gas tube electrode in said space in the path of said stream; a source of high potential connecting said electrodes; and, means controlled by the setting of said fluid flow control valve for discharging a gaseous fluid downwardly into said space alongside said gas tube electrode.

3. An apparatus for applying particles to a surface which comprises a gas-fllled electrode, an electrode in proximity thereto for supporting said surface, means for impressing a high potential alternating E. M. F. between said electrodes, and, means for holding particles to be applied to said surface comprising wail members respectively having afree end, a cushioning mem-' ber'on the free end of each of said wall members, and rotary feed means bracketed by said wall members and engaged by said cushioning members.

4. An apparatus for applying particles to a surface which comprises a gas-filled electrode, an electrode in proximity thereto for supporting said surface, means for impressing a high potential alternating E. M. F. between said electrodes, and, means for holding particles to be applied to said surface comprising wallmembers in converging relationship, said wall members being flexibly mounted' and respectivelyhaving a free end, a cushioning member carried by the free end of each wall member and a rotatabiy mounted feed member of cylindrical contour positioned between said wall members at the free ends thereof with its circumferential periphery in rotary sliding engagement with said cushioning members.

5. Web treating apparatus comprising in combination, means forming a ground electrode for supporting a moving freshly printed surface; means for holding and depositing finely divided absorptive material in a continuous stream in the space above said supporting means including wall members having free lower edge portions mounted for inward yielding movement, rotary

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