US 3504626 A
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Description (OCR text may contain errors)
April 7, 1970 E. w. WORTHINGTON 3,504,626
PRINTING PRESS DAMPENING CONTROL SYSTEM Filed April 13, 1965 3 Sheets-Sheet 1 INVENTOR. EMORY W. WORTHINGTON MORGAN, FINNEGAN, DURHAM 8 PINE ATTORNEYS April 7, 1970 E. W. WORTHINGTON PRINTING PRESS DAMPENING CONTROL SYSTEM Filed April 13, 1965 souzcE SENSOR CON T101- 3 Sheets-Sheet 2 I/II/I/ I/I/ I/l/ INVENTOR. EMORY W. WORTHINGTON MORGAN, FINNEGAN, DURHAM 8 PINE ATTORNEYS April 7, 1970 E. w. WORTHINGTON 3,504,626
PRINTING PRESS DAMPENING CONTROL SYSTEM Filed April 13, 1965 3 Sheets-Sheet 5 INVENTOR. EMORY W. WORTHINGTON BY MORGAN, FINNEGAN, DURHAM 8| PINE ATTORNEYS United States Patent U.S. Cl. 101-148 12 Claims This invention relates to dampening arrangements employed in lithographic printing systems and more particularly to techniques and arrangements for controlling the dampening operation.
An object of the invention is to prOVide an improved dampening technique for use with lithographic printing presses, further objects being to effectuate improved control over the water/ ink balance, to reduce spurious dampening fluid dispersion, and to inhibit the contamination of the dampener feed system by feedback from the inking and impression system.
Other 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, combinations, arrangements and improvements herein shown and described.
Serving to illustrate exemplary and preferred embodiments of the invention are the drawings of which:
FIGURE 1 is an elevational view partly in section and partly schematic of a dampening system illustrating certain arrangements according to the invention;
FIGURE 2 is an enlarged elevational view partly in section and partly schematic of the water supply system of FIGURE 1;
FIGURE 3 is an elevational view partly in section and partly schematic of a further embodiment of the invention; and
FIGURE 4 is an elevational fragmentary view on enlarged scale and partly in section illustrating a detail of the water metering arrangement of FIGURE 3.
For convenience the ink rejecting solution is frequently referred to herein as water although it is to be understood that other solutions may be employed.
It is also to be understood that while the damping arrangements herein described are illustrated in connection with that type of dampening which applies the water to one of the form rollers of the inking train (see Roberts Patent 3,094,065), certain of the arrangements are applicable as well to other dampening systems such as those which apply the Water to the plate cylinder directly, independently of the form rollers.
The system of FIGURES 1 and 2 comprises a lithographic printing press which, so far as the inking and impression system is concerned, is of conventional form and may be, for example, a sheet fed offset press. It includes a blanket cylinder 1 and plate cylinder 2 in contact therewith. The inking system is shown in part and comprises a plurality of form rollers including a first form roller 5 and a plurality of successive form rollers 3, all in engagement with the plate mounted on plate cylinder 2. A pair of vibrating or reciprocating rollers 4 are included which engage respective pairs 3, 3 and 3, 5 of the form rollers and which vibrate or reciprocate axially in the usual manner to effect a uniform distribution of the ink film. Rollers 4 are preferably metallic and have surfaces which may be steel or copper-plated steel. The form rollers 3 have ink-receptive surfaces which may 3,504,626 Patented Apr. 7, 1970 be resilient rubber or an appropriate plastic composition material.
A water supply system engages form roller 5 to supply water thereto in accurately controlled amounts. This system includes a distributing roller 7 which is preferably chrome plated or nylon covered in such a way as to be water-receptive and which engages the surface of form roller 5 to transfer to the form roller the film of water carried on 7. Control over the quantity of water carried by distributor roller 7 is effected by a control roller 6 which is preferably covered with a synthetic rubber and which is adjustable by adjustment means schematically indicated at A so that the contact pressure between it and distributing roller 7 may be set to control the supply of water to the distributing roller. Roller 6 may also be of the molleton covered type.
Water is transferred from a water fountain 11 tothe distributing roller 7 by means of a fountain roller 8 which is preferably coated with a synthetic plastic such as Hypolan or a synthetic rubber of the Buna type. Roller 8 is in engagement with distributor roller 7 and is also immersed in the ink rejecting solution in fountain 11. Rollers 7 and 8 may be geared together as schematically indicated at G and driven from a variable speed drive including a motor M and an adjustable speed reducer R. An illustrative speed range for roller 8 is 5-30 r.p.m. Roller 6 is frictionally driven from roller 7 which the peripheral speed of roller 7 is generally less than the peripheral speed of form roller 5. The latter is frictionally driven by the plate cylinder.
The positional relationship between rollers 7 and 8 may be adjusted by adjusting means A to provide further control over the water supply. In addition, the entire dampening feed mechanism including rollers and fountain may be adjusted as a unit by adjusting means A to establish the appropriate operating contact with form roller 5.
The water feed system is susceptible to contamination by paper, paper dust, lint, ink, emulsion and other foreign matter which is transferred back to the fountain roller 8 from roller 7 and thereby tends to get into the water supply in fountain 11. To substantially inhibit this contamination and to prevent emulsification of the ink in the moistening fluid, a strainer system is provided which includes a flexible strainer 10 having one end engaging the end 11a of the fountain 11 and the other end attached to a resilient wiping blade 9 that engages the surface of fountain roller 8 and removes foreign matter fed back to the surface of roller 8. This foreign matter, which is entrained in the emulsion fed back to the blade, is collected in the strainer strip and confiend to that section of the fountain which is isolated *by this strip, it being noted that the sides of the strip are in substantial sealing engagement with the sides 11b of the fountain (see FIG- URE 2).
The strip 10 is a water permeable barrier preferably of non-woven fabric. One end of the strip is secured as by an adhesive or heat sealing to a clip 15 illustratively of plastic and adapted to engage the upper lip of the fountain end 11a. The clip may include a strip of resilient material 15a such as nylon to establish a secure connection. At its opposite end the strip 10 is secured as by an adhesive or by heat scaling to a plastic molding 16 and this molding is adapted to be secured to the blade support 17.
The blade support 17 includes end connections, not shown, for connection to the side walls 11b of the fountain. The blade 9 is attached as by screw 17a and clamping strip 17b to the upper surface of the support.
The extension of the blade 9 remote from roller 8 is employed in combination with a cam 13 to provide a quick-release type connection of strainer to the holder 17. Cam 13 is supplied with a handle 14 and when rotated the lobe of the cam elevates the remote end of blade 9 to thereby free the end piece 16 of the strainer which is otherwise clamped to the holder 17 by the blade extension.
The major portion of the strainer 10 is immersed in the fountain solution and its sides engage the sides 11b of the fountain so that the strained material is confined to the one section of the fountain which is delineated by the strainer.
In the flow control system, the level of dampening fluid in fountain 1.1 may be maintained within limits by a system as shown in FIGURE 2 which comprises a liquid level sensor 50 whose output, electrical or mechanical, signals a valve controller 51. The latter is preferably electromechanical and operates a valve 52 which controls the delivery of fluid from the dampener source to the fountain to maintain the proper level.
In FIGURE 3 the water feed system includes, in addition to the foregoing elements, a water feed control arrangement. As embodied, this apparatus is associated with the fountain and includes a Wick 17 having one end immersed in the fountain supply and the other end in engagement with fountain roller 8. The non-woven wick provides a capillary feed action and the end in contact with fountain roller 8 is secured or bonded as by casting, to a strip 22, illustratively of plastic, and having in a slot on its exterior surface, a pressure distributing metallic strip 21 which may be spring bronze or stainless steel (see FIGURE 4). In adjustable engagement with the plastic section 21 of strip 22 are a plurality of adjusting thumb screws 19 in side-by-side array across the width of the fountain roller. Each screw 19 is threaded in a respective tapped hole in a block 18 attached to a base 18a. The latter is pivoted to the fountain 20 as illustrated in FIGURE 3. To distribute the load, the distal end of each screw includes a reduced shank disposed in a corresponding hole in the strip 21 with the shoulder portion bearing against the strip via a respective washer 19a.
Pressure adjustment, as established by the setting of adjustment screws 19, controls the amount of fluid transferred by capillary action in wick 17 from the fountain to roller 8. The plastic section 22 should have relatively little elastic memory to insure rapidly responding adjustments. Preferably, the wick 17 comprises plastic fibres selected so that they may be bonded together and so that there is relatively low friction between the wick and the surface of roller 8 under low pressure conditions. Where required, the adjusting mechanisms can include resilient members such as springs.
It may be seen by an inspection of FIGURE 3 that virtually the entire surface of liquid in the fountain is substantially sealed from the atmosphere. This seal is accomplished by the fountain itself, by the strainer 10 and by the feed wick 17 and plate 18a, all of which elements extend across the width of the fountain. Since the dampening fluid frequently includes alcohol solutions, this sealing of the fountain supply can provide significant savings in material costs and in the cost of checking and maintaining the proper balance of ingredients in the dampening fluid.
It may also be noted that the capillary feed permits the roller 8 to be otherwise isolated from the fountain thereby affording a greater flexibility in the design of the filter or strainer and the isolation of return flow from the fountain. For example, blade 9 can feed the return flow through a separate filter which has an output leading to the fountain.
In the study and practice of the invention, modifications will undoubtedly occur to those skilled in the art. The invention is thus not limited to the specific mechanisms shown and described, but departures may be made therefrom Within the scope of the accompanying claims.
What is claimed is:
1. A dampener control system for a printing press comprising a fountain for holding dampening fluid, roller means positioned above said fountain, means for rotating said roller means, adjustable capillary feed means in fluid communication with said fountain and the feed portion of said roller means for feeding said fluid to said roller means, a plurality of adjusting means, each for setting any one of a range of predetermined pressures between said feed means and roller means at a respective point axially along said roller means; and fluid transfer means inter-connecting said roller means with said press means for transferring said fluid thereto.
2. A system as defined in claim 1 in which said capillary feed means comprise a fibrous sheet material having one edge immersed in said fountain and the other edge in contact with said roller and the portion in between said edges unrestrained.
3. A system as defined in claim 1 in which said capillary feed means and adjustment means are disposed to seal off a substantial part of said fountain.
4. A system as defined in claim 1 including strainer means coupled to the return portion of said roller means and disposed in said fountain to isolate a portion thereof for preventnig foreigh matter and emulsion from polluting other portions of said fountain.
5. A system as defined in claim 4 in which said strainer means comprise means for diverting return flow from said roller means and a straining material oriented to receive said diverted flow and to feed the affluent to said fountain.
6. A system as defined in claim 5 in which said strainer material is disposed in a concave configuration partially immersed in said fountain.
7. A dampener control system for a printing press comprising a fountain of dampening fluid, rotatable transfer means in association with said fountain and having a fluid flow surface for transferring said dampening fluid therein to said press, capillary means in fluid communication with said fluid flow surface and said dampening fluid for controlling the transfer and flow of said dampening fluid thereto, said capillary means including a wick having one end immersed in said dampening fluid fountain, a pressure transmitting strip at its opposite end which engages said flow surface, and axially variable pressure adjustment means engaging said strip for controlling the capillary action of said capillary means, and strainer means in communication with said fluid flow surface and said dampening fluid, said strainer means and said capillary means being oriented to enclose a substantial part of said fountain of dampening fluid.
8. A system as defined in claim 7 in which said capillary means comprises a non-woven fibrous material.
9. A dampener control system for a printing press comprising a fountain of dampening fluid, fluid transfer means in communication with said fountain and said press, said transfer means ncluding a rotatable fluid flow receiving surface, strainer means in communication with said rotatable fluid flow receiving surface and said dampening fluid, said strainer means including wiper means urged against the rotatable fluid flow receiving surface in its flow return region, a strainer element releasably clamped to said wiper above the level of said dampening fluid, and means for immersing said element in said dampening fluid.
10. A system as defined in claim 9, in which said strainer means includes a concave portion partially immersed in said fountain with the distal end engaging the side of said fountain.
11. A system as defined in claim 9, including capillary feed means coupled to said fluid flow receiving surface for feeding dampening fluid thereto.
12. A system as defined in claim 11, including a cover plate for said fountain in which said cover plate and said 5 6 strainer means provide substantial enclosure of said foun- 3,097,597 7/ 1963 Visser 10l364 tain. 2,465,160 3/1949 Levenhagen et a1. 101132.5
References Cited FOREIGN PATENTS UNITED STATES PATENTS 1,082,283 5/1960 Germany.
1,812,720 6/1931 Schultz l0l365 5 1,900,266 3/1933 Wood 101 363 ROBERT E. PULFREY, Primary Examiner 2,126,768 8/ 938 G e ke 101- 47 FISHER, Assistant Examiner 2,368,500 1/1945 Taylor et al. 10l-350 2,406,928 9/1946 Taylor l01350 1 US. Cl. X.R.
0 3,010,393 11/1961 Worthington lOl425 101-350, 365