US1954550A - Duplicating device - Google Patents

Description

April 10, 1934. R. WEIDE DUPLICATING DEVICE 2 Sheets-Sheet 2 Filed June l5 1932 |||||||||I||| |||||I|||||| l||||||||||| lHll Patented Apr. 10, 1934 PATENT, OFFICE DUPLICATING DEVICE Rudolph Weide, Chicago, Ill., assgnor to Ditto Incorporated, a corporation of West Virginia Application June 15, 1932, Serial No. 617,461

Claims.

The invention relates to duplicating devices and has as its primary object the provision of improved apparatus for and an improved method of offset duplicating wherein positive master sheets I may be employed.

The improved apparatus preferably comprises means similar to means employed in offset printing presses, the construction being such that an impression is taken from the master sheet on the impression or offset roll each time the impression or offset roll produces a duplicated copy.

The invention is particularly advantageous as it permits one to obtain a relatively large number of distinct copies from the master sheet and also ll permits one to employ the same master sheet from time to time over a period of years if it is so desired. Another particular object of the improved method is that one may apply the design or data to the master sheet in a plurality of colors with comparatively little effort.

Other objects and advantages will become apparent as the following detailed description progresses, reference being had to the accompanying drawings wherein,

Figure 1 is a longitudinal fragmentary section taken through a duplicating machine which embodies the invention, the section being taken on line 1---1 of Figure 2.

Fig. 2 is a front elevation of the improved ma- 80 chine.

Fig. 3 is a section ltaken on line 3--3 of Fig. 2.

Fig. 4 is a section taken through an impression roll which embodies another form of the invention, and

Fig. 5 is a fragmentary section taken on line 5-5 of Fig. 4.

Referring for the present to Figures l to 3, inclusive, wherein a preferred embodiment of the invention is illustrated, the reference character 10 designates a frame of a duplicating machine which also comprises a master carrying roll 1l, an impression or offset roll 12 and a. platen roll 13. The rolls v 11, 12 `and 13 are mounted on shafts 15, 16 and 17, respectively, journaled in the frame 10. Fixed to the shaft 16 is a gear 18 'which meshes with a pinion 18 which in turn meshes with a pinion y19 fixed to a shaft 20 journaled in the frame 10. A sprocket 21 iixed to the shaft 20 is adapted to drive a sprocket 23 through the medium of a sprocket chain 24, the sprocket 23 being fixed to a shaft 25 which is journaled in the frame 10. The shaft 25 carries a. rubber covered feed roll 28 which frictionally engages a lmetallic pressure roll 29 fixed to a shaft 30 jour naled in the frame 10.

The feed roll 28 also frictionally engages a moistening roll 32 which forms a. part of a moistening device 33. The moistening device 33 comprises a tray 34 which holds a supply of liquid as hereinafter described. The roll 32 is driven 60 by the roll 28 and moistens the roll 28 in a manner well known to those skilled in the art. 'Ihe moistening device 33 also comprises a doctor blade 35 which regulates the amount of liquid delivered to the roll 28 by the roll 32. The roll 32 ss is preferably formed from metal and the cylindrical surface thereof is preferably etched to provde a fine screen-like surface thereon.

The shaft 20 is provided with a handle 38, or the equivalent, whereby the shaft may be rotated to rotate the drum 12 through the medium of the gears 19, 18, and 18. A gear 39 fixed to the shaft 16 meshes with a gear 40 fixed to the shaft 15. Obviously, when the shaft 16 is rotated, the shaft l5 will rotate in synchro- 75 nism therewith. Likewise, the shaft 25 will rotate in synchronism with the shafts 15 and 16.

As best shown in Figures 2 and 3, the roll 1l is provided with clamping means 42 whereby one end of a master sheet 32 may be secured to the 80 roll. The clamping device 42 comprises a` bar 45 movably mounted in a groove 47 extending longitudinally of the roll 11. Engageable with the bar 45 is an eccentric 48 fixed to a shaft 49 which is journaled in the roll 11. One end of the shaft 49 is squared as at 50 so that a wrench, or the equivalent, may be applied thereto when one wishes to displace the shaft 49 angularly.

A nut 52, screw threaded upon the shaft 49 provides means whereby the shaft may be secured in a plurality of adjusted positions. When the master sheet 43 is to be applied to the roll 11, one end of the sheet is inserted between the bar 45 and a shoulder 55 formed in the groove 47. The shaft 49 is then rotated until the sheet 95 is clamped firmly between the bar 45 and the shoulder 55, after which the nut 52 is tightened. As indicated in Fig. 3, it is not necessary to secure the other end of the master sheet to the m11 11. 10

The master sheet 43 is a positive. In this instance, it has lettering 56 on it, which lettering may be in a plurality of colors. Any suitable material may be employed in printing or forming the lettering 56 upon the master sheet. Thus, aniline inks, or the equivalent, of the type commonly employed in connection with hectograph machines may be utilized.

The roll 12 is provided with a coating 60 of no rubber, or any other suitable material. The roll 13 is lpreferably formed from hard rubber.

The improved machine is provided with a feed table 62 from which sheets of paper 63 may be advanced manually to a position where they will be engaged by the rolls 28 and 29 and advanced across a guide plate 64 to the impression or offset roll 12. The platen roll 13 co-operates with the roll 12 to advance the sheets, it being the primary function of the roll 13 to press the sheets into firm contact with the rubber coating or blanket 60. When the sheets pass from between the rolls 12 and 13 they are stripped from the coating 60 by a stripping blade 65 fixed to the frame 10. The sheets then fall on an inclined table or guide plate 67.

The liquid in the tray-34 is a solvent for the aniline ink, or the equivalent, employed to print or form the lettering 56 on the master sheet 43. Alcohol has been employed with excellent results.

The shaft 15 is preferably journaled in eccentrics 70 journaled in bosses 71 provided upon the frame 10. Set screws 73 screw threaded in the bosses 71 provide means for locking the eccentrics in adjusted positions. It will be readily understood that the pressure exerted by the roll 11 on the rubber blanket 60 may be adjusted by adjusting the eccentrics.

The shaft 17 is also adjustably mounted. Thus, its ends are journaled in eccentrics 75 which are journaled in bosses 76 provided on the frame 10. Set screws 77 screw threaded in the bosses 76 may be manipulated to secure the eccentrics in adjusted positions.

The operation of the above described apparatus is substantially as follows:

When the master sheet 48 has been properly secured to the roll 11, the sheets to be duplicated are advanced from the table 62 to the rolls 28 and 29. The roll 28, which is moistened by the roll 32, moistens the top surfaces of the sheets of paper and they, in turn, moisten the roll 12. The roll 12 then moistens the lettering on the master sheet and some of the ink, or the equivalent, of the lettering is dissolved by the solvent so that the lettering is impressed or printed in negative on the rubber coating or blanket 60. Then, as one continues to feed the sheets 62 through the machine, the negative impression or printing on the rubber coating or blanket 60 is transferred to the sheets in positive printing. The operation of the machine may be continued as long as desired or until the supply of ink upon the master sheet 43 has been substantially exhausted. It is readily understood that as long as the machine is operated, the sheets 62 moisten the roll 12 continuously, and it, in turn, continually moistens the lettering on the master sheet. If it is so desired, a few copies may be made of the master sheet and it may be stored away for future use.

It will be readily understood that the rolls 11 and 12 are identical in diameter so that each time the lettering 56 is imprinted in negative upon the rubber coating 60, it will be in registry with the preceding imprints thereon of the same letters.

Referring now to Figs. 4 and 5, which illustrate another form of the invention, the reference character 12a designates generally an impression or offset roll which may be employed in place of the impression or offset roll 12 described above. The roll 12a comprises a metallic cylindrical wall 12b provided with a longitudinally extending groove 47a in which a shaft 47h is mounted. The shaft 47h extends parallel to the shaft 16a which is preferably identical with the shaft 16 described above and has the same function. Mounted on the shaft 47h is a. rotatable member 47e provided with a hook or flange 47d. Fixed to the rotatable member 47e at one end thereof is a ratchet 47) which is engageable by a pawl 47g pivoted to the roll 12a. A spring 47h yieldingly urges the pawl 47g into engagement with the teeth of the ratchet 47j. The pawl is provided with a finger piece 477 whereby one may withdraw the pawl from engagement with the ratchet against the action of the spring 47h.

A coating or blanket 60a formed of rubber, or any other suitable material, is provided at one end with a hook 60h engageable with the flange 47d provided upon the rotatable member 47e. The other end of the blanket 60a is provided with a hook 60e engageable with a bar 60d secured to the roll 12a. A lever 47k fixed to the rotatable member 47c provides means whereby one may displace the rotatable member 47a angularly on the shaft 47h.

When the blanket 60a is to be applied to the roll 120, its hook 60e is rst engaged with the bar 60d whereupon the blanket is wrapped around the roll until its hook 60h may be engaged with the flange 47d on the rotatable member 47e. The lever 47k is then angularly displaced to displace the rotatable member 47o to draw the blanket 60a taut around the roll. The pawl 47g will hold the rotatable member 47c in its adjusted position until one angularly displaces the pawl against the action of the spring 47h.

With the construction shown in Figures 4 and 5, the blanket or coating on the impression or offset roll may be replaced from time to time or it may be removed if one wishes to clean it. It will be readily understood that if the roll 12a is substituted for the roll 12, the machine shown in Figures 1 to 3, inclusive, will continue to function as described above.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is my intention to claim all novelty inherent in my invention as broadly as possble, in view of the prior art.

I claim:

1. A duplicator comprising a roll, means carried by the roll for securing a master sheet thereto, an offset roll adapted to receive impressions from said sheet of paper, means for moistening a sheet to be duplicated, and means for pressing said moistened sheet against said offset roll, said last mentioned means co-operating with said offset roll to advance the sheet.

2. A duplicating machine comprising a roll, means carried by said roll for securing a master sheet thereto, an offset roll driven in synchronism with the first mentioned roll and adapted to receive impressions from said master sheet, means for moistening a sheet, to be duplicated, with a solvent, and means for pressing the moistened sheet against the offset roll and cooperating therewith to advance said sheet.

3. A duplicating machine comprising a roll, means carried by said roll for securing a positive master sheet thereto, an offset roll driven in synchronism with the first mentioned roll and adapted to receive impressions in negative from said master sheet, means for moistening a sheet, to be duplicated, with a solvent, and means for pressing said moistened sheet against said oiset roll to transfer said impression from said offset roll to said moistened sheet, the impression on said moistened sheet being in positive.

4. The method of duplicating which comprises moistening sheets to be duplicated, transferring said moisture from said sheets to a positive master sheet to dissolve a substance imprinted thereon, taking a negative impression of the imprint on said master sheet, and then bringing sheets to be duplicated into contact with said

Images