US2492377A - Moistener for duplicating machines - Google Patents

Description

Dec. 27, 1949 J. J. CAMPHOUSE MOISTENER FOR DUPLICATING MACHINES 4 Sheets-Sheet 1 Filed April 30, 1945 1949 J. J. CAMPHOUSE 2,492,377

MOISTENER FOR DUPLICATING MACHINES Filed April 30, 1945 4 Sheets-Sheet 2 ,By W

1949 J. J. CAMPHOUSE 2,492,377

MOISTBNER FOR DUPLICATING MACHINES Filed April 30, 1945 4 SheetsSheet 4 glmumm VIZ/07722503 Patented Dec. 27, 1949 2,492,917 morsraunn ron nurmcarme MACHINES John J. Camphouse, Oak Park, Ill., assignor to Ditto, Incorporated, Chicago, 111., a corporation of West Virginia Application April 30, 1945, Serial No. 591,179

Claims. (01. 91-49) 9 the surface of a copy sheet as it is being fed into pressure contact with the master sheet.

Previous devices of the roller moistener type employ as anagency for transferring solvent to the surface of the moistening roll, either a fibrous material, or a pump. Both of these expedients are undesirable in certain respects; the fibrous material is subject to wear and requires frequent adjustment, and occasional replacement; and a pump is a comparatively costly item which is subject to mechanical difliculties, such as breakage or wear. Furthermore, both of these expedients, unless subject to continuous control, tend to oversupply liquid or solvent to the moistening roll. Furthermore, when the moistening roll is stationary, certain kinds of solvent exhibit a tendency to creep along the surface of the roll and collect at the bite of the feeding rolls.

I have found that if a small body of liquid is maintained under subatmospheric pressure against the surface of the moistening roll, that creepage is eliminated when the roller is stationary, but that rotation of the roll causes liquid to be withdrawn from the small body of liquid and to be spread over the surface of the roll in a very thin and uniform film.

Other objects are to provide an improved moistening means which is of simple construction, to provide one which does not embody parts which are subject to wear, to provide one which renders a duplicating machine ready for instant operation without the necessity of priming, to provide one which is in the form of a removable unit to facilitate inspection or cleaning thereof, and to provide an improved means for feeding the solvent to the moistening unit.

With reference now to the drawings, in which like reference numerals designate like parts,

Fig. 1 is an elevation of a duplicating machine embodying a preferred form of this invention;

Fig. 2 is an end view of the solvent reservoir shown in Fig. 1;

Fig. 3 is an enlarged sectional elevation through the machine shown inFig. 1;

Fig. 9 is an enlarged sectional elevation taken along line 8-8 of Fig. 4;

Fig. 10 is a section through the lower part of the reservoir showing the valve therefor and the mounting thereof; and

Figs. 11 and 12 are details of certain of the parts shown in Fig. 10.

With reference now to Figs. 1 and 3, the dupl cating machinecomprises a pair of side frames l5 and it between which a drum II is mounted on a shaft It. A pressure roll it is disposed beneath the drum and is urged into pressure contact therewith by suitable means, not shown herein, the pressure roll being mounted on arms 20.

A crank 2| is disposed at'the exterior of side frame I! and is adapted to drive the drum through suitable gearing 22. The drum is provided with the usual gripper 23 which grips the leading edge of a master sheet 24.

The operation of the device is such that when a moistened copy sheet passes through the bite of the drum l1 and pressure roll II. it is urged into contact with the'master sheet 24. The surface of the master sheet is provided with the usual inked characters. and the nature of the solvent is such that a small amount of the ink is dissolved each time a copy sheet is pressed against the master sheet, the dissolved ink being transferred to the surface of the copy sheet. After the copy sheets have passed through the bite of the drum and pressure roll, they drop into the usual receiving tray 25.

The duplicating machine is provided with a feed tray 21, upon which the copy sheets may rest in a stack 26, and a suitably driven feed roller 28 is provided to remove the top sheet from the stack at the. proper intervals.

Between the stack 2 and the bite of the drum and pressure roll, are mounted a pair of feed rolls 30 and 3|, the upper feed roll 30 also serving to apply a thin film of moisture to the surface of a copy sheet. The feed roll 30 is mounted on a shaft 32, there being a free wheeling connection between the two so as to permit unidirectional rotation of the feed roll. The shaft 32 may be driven in any suitable manner, as by a rack 33 mounted on a bell crank 34 which is pivoted on the side frame I6. The bell crank carries a cam follower 35 which engages a cam 38 mounted on the drum shaft I 8 and rotating therewith. Rotation of the drum and of the cam 38 will cause reciprocation of the rack 33, thus driving the shaft 32 through a suitable pinion, and hence driving the feed roll 3|.

The lower feed roll II is mounted in a pair of 3 arms which may be suitably pivoted with respect to the side frames and biased into contact with the feed roll 30 so that the feed roll 3| is driven by frictional contact with feed roll 30.

The arrangement is such that the feed rolls are stationary during a portion of each revolution of the drum. The feed rolls start to rotate as the drum through a given. angular position, and the timing is such that the leading edge of the copy sheet is advanced by the feed rolls so that it will engage the master sheet in the desired registry. After the leading-edge of the copy sheet has been engaged by the bite of the drum and the pressure roll, the pull of the copy sheet causes the continued rotation of the feed rolls 30 and 3| even though there is no driving connection between the shaft 32 and the eed roll 30, due to the free wheeling connection and the reverse motion of the rack 33.

A moistening unit designated generally by the reference numeral 38 is disposed adjacent the feed roll 30. The moistening unit comprises a pair of slotted end'members 39 and 40 which are slidably mounted on lugs 41 and 42 attached to the side frames l and it. A transverse member 43 connects the'end members 39 and 4c and also forms the bottom and side wall of the moistenlng unit. The forward edge of the transverse member 43 is turned up as indicated in Figs. 6, '7 and 9 to provide a trough 44 forthe reception of liquid.

The end members -39 and 40 include bosses 45 and 46 which are recessed-to accommodate the projecting end portion of an L-shaped block 41. Plates 49 and 50 are screwed to the upper surfaces of bosses 45 and 4B and serve to confine the projecting end portions of the L-shaped block 41 within the recesses. The arrangement is such that the L-shaped block is enabled to slide toward and away from the feed roll 30. as;

shown in Figs. 6 and 4. v

" A second L-shaped block 48, smaller than the first, is mounted within the angle of the first, the two outer surfaces of the block 48 being spaced from the two inner surfaces of block 41':

to form an L-shaped passageway leading from the trough 44 to the surface of roll 30. The dimensions ofthis passageway, which include a vertical leg' 53 and a horizontal leg 54. which intersect, are small and form -a narrow fissure which runs the "whole length of the L-shaped blocks 41 and 48, and which is practically as wide as the roll 30.

The operation of the device is such that a small body of liquid is always maintained in contact with the surface of'roll 30. This is due to the fact that once the liquid in trough 44, has been drawn up into the vertical and horizontal legs of the fissure and wets thatportion of the roll surface which closes the end of the horizontal leg 54, the roll acts as a seal which maintains :the liquid in the fissure. When the roll 30 rotates, the effect is a pumping action which with- 1 draws liquid from the horizontal leg 54, thereby reducing the pressure within the fissure and cansing an equal amount of liquid to be forced up into the fissure from the trough. The liquid within the horizontal leg 54 is under subatmospheric pressure, the pressure being equal to the atmospheric pressure less the hydrostatic head at that point. Due to this reduced pressure the liquid .will not flow out ofthe fissure and down the surface of roll 30 when the roll is stationary. The result is that the proper amount of liquid is applied to the surface-of the roll when it is rotat- Fig. 6.

that the solvent used has a comparatively low surface tension. This apparently explains the extremely unpredictable behavior of the solvent in various moistening constructions, because it has been found that even when the rolls are stationary, if there is a body of liquid in contact with the surface of the roll, this liquid will creep upwardly or downwardly. and will tend to collect in a bead at the bite of the two feed rolls. Thus when the leading edge of a copy sheet is advanced into the bite of the stationary rolls, the

leading edge will become saturated with the solvent, and thus crash" or dissolve an undue amount of ink from the master sheet.

With the construction herein shown and described, however. it has been foundthat such creeping does not occur. This may be due to the fact that the amount of liquid in contact with the surface of the roll is extremely small, orit may be due to the fact that the amount of liquid is maintained under a subatmospheric pressure,

-or it may be due to a combination of both of those reasons, or there may be other explanations of which I am not presentlyaware. I have found that satisfactory results are ob,-

- tained when the width of the verticalleg is main:-

tained at .010 inch, and the width of the hori} zontal leg is .003 inch. '1

However, it is obvious that considerable variation may be made in the dimensions of the gap. and under varying conditions such variation ma be necessary. To effect such variations adjusting screws SI and 52 are provided for adjusting the width of the vertical leg 43 and adjusting screws 55 and 56 are provided for the horizontal leg 54. The operation of these adjusting screws is shown in Fig. 9 in which it will be seen that the shank of the screw extends through the L-shaped block 41 and the threads engage the L-shaped block 48. The block 41 is provided with a recess 51, and a small spring 58 is confined in the recess and surrounds the adjusting screw 52 and bears against the block 48. To the left of the recess 51, as shown in Fig. 9, sufilcient clearance is provided around the shank of the screw to permit adjustment of the same. This same arrangement is provided for all of the adjusting screws.

A top plate 60 extends between the end members 39 and 40 and cooperates with the transverse member 43 to form a substantially rigid structure. Lugs 6| are provided on the top plate to which levers 62 are pivoted, the lower ends of the levers bearing against the L-shaped block 41. To the vertical portion of the transverse member 43 are staked threaded collars 63, as shown in Set screws 64 are located within the threaded collar 63 and bear against springs which serve to regulate the tension on the lever 62, thus causing the assembly comprising the blocks 41 and 48 to be resiliently urged against the surface of roll 30. It can be pointed out that close contact isdesirable between the blocks and the roll, but too much pressure is undesirable .be-

A cross bar 56 is disposed between the side frames I5 and I6, and -carries spring latch members 61, as shown in Fig. 3. These latch members are provided with shoulders 68 which hook under an L-shaped strip 69 which is suitably secured to the top plate 50.

A cover is provided for the moistening' unit, and is suitably secured'to the vertical portion of the transverse member 43, as shown in Fig. 3. The collars 1| are staked to the cover and serve as guides for plungers 12, the location of the collars being such that the plungers engage the latch members 61. The construction of the moistening unit 38 is such that it may be readily removed from the machine by sliding it to the left, as shown in Fig. 3, thus disengaging the slotted end members 39 and 40 from the lugs 4| and 42. This cannot be done however, until the plungers 12 are depressed to release the latch members, the moistening unit being otherwise locked in the proper position. The shape of the latch members and the shoulders 68 is such that the moistening unit may he slid into latched position without manipulation of the plungers 12. As shown in Figs. 4

and '7, brace members 13 are provided to prevent spreading of the slotted end members 39 and 40.

Liquid is supplied to the trough 44 from a reservoir'comprising a bottle 16, the arrangement being such that a substantial level of liquid is maintained in the trough 44, said level being higher than the lower-surfaces of the blocks 41 and 48. Thus the fissure which, in the present embodiment, is of capillary dimensions is maintained full of liquid, and the machine is at all times ready for operation without the necessity of priming it. The bottle 16 is supported on a bracket which includes an L-shaped pipe coupling l1 suitably secured to the side frame I8, as by welding, as shown in Fig. 2. A short horizontal length of pipe 18 is securely mounted at one end in the pipe coupling 11, and at the other end supports a socket indicated generally by the reference numeral 19 for the reception of the bottle 16. As shown in Fig. 10, the socket includes a cup shaped member 80 in which is mounted a headed stem 8|. A disk valve 82 surrounds the stem 8| for vertical movement, and is urged upwardly by a spring 94. A cap 84 is threaded onto the upper portion of the cup shaped member 80 and is apertured to receive the mouth of bottle 18. It will be seen that when the bottle is not in position, the spring 94 urges the valve into closed position against the head of the stem 8|, and against the seat formed by the lower surface of the cap 84. When the bottle is in position, the valve is pressed downwardly against a seat 83, suitably formed in the wall of the cup shaped member 80. In this position, which is shown in Fig. 10, communication is established between the bottle 16 and the other portions of the device through the central aperture 95 of the valve disk 82.

The central aperture in cap 84 isformed with half threads 85 which cooperate with half threads 85 formed on the neck of the bottle 16, as'shown in Figs. 10 and 11. Thus the bottle may be forced into the cap and against the valve disk 82, and then given a half turn to tension the parts, the valve disk preferably being made of rubber or like material which has a slight resilience and will form a good seal.

The left end of the other horizontal length of pipe 18 is enlarged as shown at 81 in'Fig. 10. An apertured cap 88 is provided for the lower projecting portion of the cup shaped member 80 in which the enlarged end 81 is received, and cooperates with the other parts to form a packing gland 89. The arrangement is such that the socket and the bottle may be rotated about a horizontal axis, as shown in broken lines in Fig. 1. Thus the bottle may be inserted or removed when it is in the dotted line position shown without spilling any of the contents. The valve disk 82 and its associated parts prevent the spilling of the liquid remaining within the socket when the parts are in the dotted line position. A brace 96 suitably welded to the side frame l6 serves to maintain the bottle 16 and its associated parts in a substantially vertical, slightly overcenter position for normal operation of the machine.

A flexible and removable tube serves as a connection between the pipe coupling 11 land a vertical length of pipe 9|. The pipe 9 I, as shown in Fig. 9, is suitably secured to the moistening unit 38, and its lower end, which is diagonally cut as indicated by the reference numeral 92, is disposed in the trough 44. Due to the diagonal cut, the lower edge of the pipe 9| rests on the transverse member 43, land a lateral opening is provided which determines the level of the liquid within the trough 44.

The operation of the duplicating machine has 'been explained in detail in connection with the operation of its several parts. At this point it will be sufiicient to point out merely that as the drum I1 is rotated by the crank 2|, copy sheets are fed one at a time from the stack 26 through the feed rolls 30 and 3| into pressure engagement with the master sheet 24 which is disposed on the surf-ace 0f the drum. A thin film of solvent is applied to the upper surface of each copy sheet as it is engaged by the feed roll 30, this thin film being drawn by the feed roll from the fissure in the correct amount. When the feed roll 30 is stationary, there is no body liquid with a free surface in contact with the roll 30, and hence there is no creeping of the solvent downwardly into the bite of the feed rolls 30 and 3|. The L-shaped blocks 41 and 48 which form the walls of the fissure are resiliently urged against the surface of the roll 30 to compensate for any slight eccentricities in the cylindrical surface of the roll 30. However, the pressure between the parts is adjustable and is maintained sufilciently low as not to exert any appreciable drag on the roll 30, which drag would otherwise tend to cause slippage between the roll and the copy sheet when the former is driven by the latter.

It is obvious that various modifications and changes may be made in the preferred embodiment of my invention herein shown and described without departing from the spirit thereof. For instance, the fissure, instead of being L-sh aped, could be diagonally disposed along a straight line, with the result that instead of L-shaped blocks, blocks of somewhat different shape could be used. Furthermore, in certain instances, it is desirable to seal off theside edges of the fissure and in such a construction the means for adjusting the width of the fissure could be eliminated.

This may be accomplished by inserting resilient rubber strips in the fissure adjacent the side edges thereof, the resilience of the rubber permitting minor adjustments of the width of the fissure. An alternative method is to apply a suitable adhesive, such as glue, or a thermoplastic, over the side edges of the fissure after the proper adjustment has been effected by means of the adjusting screws 5|, 52, 55 and 56.

It wil1 be understood that the foregoing de- 7 scription and the drawings are illustrative only and the invention is to be defined only by the appended claims.

I claim:

1. A moistener for a duplicating machine of the class described comprising a pair of feeding rolls dis-posed one above the other, a reservoir of liquid spaced therefrom, a means engaging the upper one of said rolls and'providing a single passageway extending therethrough from said reservoir to the surface of said roll, said passageway being of capillary dimensions, said reservoir of liquid having a free surface below the level of the outlet of said passageway.

2. A moistener for a duplicating machine of the class described comprising a pair of feeding rolls disposed one above the other, a reservoir of liquid spaced therefrom, a means engaging the upper one of said rolls and having a single passageway of capillary dimensions extending therethrough,

from said reservoir to the surface of said roll, and resilient means for urging said block against the surf-ace of said roll, said reservoir of liquid having a free surface below the level of the outlet of said passageway.

3. In a duplicating machine, means to supply a thin film of solvent to the surface of a copy sheet comprising a bottle shaped container, 3, swiveled socket for receiving the neck of said bottle shaped container, a trough paced from said bottle and at a lower level, a conduit extending from said swiveled socket into said trough, the lower end of said conduit being spaced from the bottom of said trough in order to maintain a predetermined level of liquid in said trough, a pair of blocks extending into said trough, the adjacent surfaces of said blocks being spaced from each other so as to form a fissure, a roll mounted adjacent said blocks and contacting with the same at one end of said fissure, the other end of said fissure terminating in said trough below the liquid level thereof, and means to rotate said roll to withdraw solvent from said fissure.

4. In a moistener for a duplicating machine, solvent supply means comprising a bottle, a swiveled socket for receiving the neck of said bottle, a trough spaced from said bottle and at a lower level, a conduit extending from said swiveled socket into said trough, the lower end of said conduit being spaced from the bottom of said trough in order to maintain a predetermined level of liquid in said trough, and a valve in said socket for engagement by the neck of said bottle to prevent the escape of liquid therefrom when said bottle and socket are rotated downwardly and the bottle removed from said socket.

5. In a duplicating machine, a moisture supplying device for applying a, thin film of liquid to the surface of a moistening roll comprising two L-shaped blocks, one fitting within the other, means for spacing the outer surface of one from the inner surf-ace of the other, to form a capillary fissure having a downwardly extending vertical leg and :a horizontal leg, the edges of said blocks adjacent the terminal end of said horizontal leg being substantially co-plan ar so as to permit substantially tangential contact with a moistening roll, whereby the liquid in said horizontal leg will be maintained under sub-atmospheric pressure.

6. A removable moistening unit for applying a thin film of liquid to the surface of the moistening roll of :a duplicating machine comprising a boxlike structure having a bottom wall shaped to form a trough, end walls, an L -shaped block slidably mounted in said end walls with one leg extending vertically downward into said trough and the other leg extending horizontally toward said moistening roll, and a second L-shaped block fitting within the angle of Said first mentioned L-shaped block and having its outer surface spaced from the inner surface of the first mentioned L-shaped block to form a capillary fissure having intersecting vertical and horizontal legs, the horizontal legs of said blocks terminating immediately adjacent the surface of said moistening roll so that liquid in said fissure will be withdrawn by the rotation of said roll.

7. A removable moistenlng unit for applying a thin film of liquid to the surface of the moistening roll of a duplicating machine comprising a box-like structure having a bottom wall shaped to form a trough, end walls, an L-shaped block slidably mounted in said end walls with one leg extending vertically downward into said trough and the other leg extending horizontally toward said moistening roll, a second L-shaped block fitting within the angle of said first mentioned L-sh-aped block and having its outer surface spaced from the inner surface of the first mentioned L-shaped block to form a capillary fissure having intersecting vertical and horizontal legs, and a spring biased arm associated with said box-like structure and bearing against said first mentioned L-shaped block to urg the same against the surface of the moistening roll, the horizontal legs of said blocks terminating immediately adjacent the surface of said moistening roll so that liquid in said fissure will be withdrawn by the rotation of said roll.

8. A moistener for a duplicating machine of the class described comprising a roll, a reservoir of liquid spaced therefrom, a liquid conveying device having a substantially vertically disposed surface engaging said roll at a point substantially mid- ;way between the top and bottom of said roll and having a passagewa of capillary dimensions extending therethrough, one end of said passageway terminating in an outlet formed in said vertically disposed surface at substantially the point where the surface engages said roll, and the other end of which passageway terminates in said reservoir at a point below the level of said outlet, said outlet being of a length substantiall equal to the length of said roll and of a width such that the liquid in the upper part of said passageway will be maintained under sub-atmospheric pressure.

9. In a duplicating machine, the combination of a moistening roll and a liquid conveying device disposed adjacent thereto and having a substantially vertically disposed surface, means for urging said vertically disposed surface into contact with said moistening roll at a point substantially midway between the top and bottom of said roll, said device having formed therein a passageway of capillary dimensions having an outlet which intersects said vertically disposed surf-ace at substantially the point where said surface contacts said roll, :a. container for liquid disposed above said device, and communicating means between said container and said passageway, said container being entirely closed, except for said communicating means, whereby the liquid in the outlet of said passageway will be maintained under sub-atmospheric pressure to prevent the fiow of liquid therethrough when said roll is stationary.

10. In a duplicating machine having a pair of rolls disposed one above the other for feeding a copy sheet, the combination of means disposed adjacent the upper one of said feeding rolls for applying a thin film of liquid to the surface thereof, said menus including a reservoir and 0 liquid conveying device providing an unobstructed passageway of capillary dimensions having an inlet and an outlet, said outlet being at a higher level than said inlet and contacting the surface of said upper feeding roll, and said inlet extending into said reservoir whereby the liquid at the outlet of aid passageway and in contact with the surface of said roll will :be maintained under subatmospheric pressure.

JOHN J. CAMPHOUSE.

REFERENCES CITED The following references are of record in the file of this potent:

Number UNITED STATES PATENTS Heme Date Rogers Aug.28,-1906 Bommico Oct. 10, 1933 Bali June 1, 1937 Btorck June 8, 1937 'rrueman et al. Sept. 5, 1939 Neal et'al Oct. 14,1941 Wilderson Nov. 24, 1942 Hardy -July 27, 1943

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