US 3397675 A
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Description (OCR text may contain errors)
Aug. 20, 1968 J, DE |GT 3,397,675
COATING APPARATUS Filed March 15, 1967 *Il/lllllllIl/Ill/ W H A mvsmoa. John De Ligt ATTORNEY United States Patent 3,397,675 COATING APPARATUS John De Ligt, Covington, Va., assignor to West Virginia Pulp and Paper Company, New York, N.Y., a corporation of Delaware Filed Mar. 13, 1967, Ser. No. 622,691 3 Claims. (Cl. 118-258) ABSTRACT OF THE DISCLOSURE A coating or printing station having its applicator and transfer rolls attached to pivotally mounted supporting frames so that the rolls may be moved into and out of operative position. Adjustable, lost motion stops are provided interconnecting the supporting frames so that the frames may be pivoted serially by means of a single source of power and the operative positions of the roller preset by adjusting the stops.
BACKGROUND OF THE INVENTION Field of the invention.Actuating systems for moving the rollers of a rotary coater or printer into and out of operative positions.
Description of the prior art.-In a conventional form of rotary coater or printer, the coating material is picked up from a supply tray or pan by a pickup roll and distributed by the pickup roller over the surface of a transfer roller. The transfer roller then transfers a layer of coating to an applicator roll which applies the coating to a web of material carried past the applicator roller by a backup roll.
In practice, the pickup and applicator rolls may be resiliently surfaced and the transfer roll provided with a relatively hard etched surface. Depending upon the surface configuration of the applicator roll, the coating may be applied to the web in either a continuous or patterned layer. In this regard it should be noted that the terms coater, coating and the like are used herein in their generic In this type of operation it is necessary to maintain a continuous layer or coating.
In this type of operation it is necessary to maintain a desired pressure or spacing, between the web being treated and the applicator roll and between each of the rolls. It is also desirable to be able to withdraw the applicator roll from the web and at least the transfer roll from the applicator roll when the coating operation is temporarily discontinued and to return the rolls to exactly their former positions when coating is again commenced. Additionally, it is necessary that these pressures or spacings be capable of adjustment to suit the requirements of specific operations.
In a known form of actuating system intended to accomplish these results, the frames for the applicator and transfer rolls are each mounted on trackways and an eccentrically mounted shaft, actuated by a hydraulically powered linkage system, is provided for each frame to slide the frames along their respective trackways and thereby move the rolls into and out of their operative positions.
It will be apparent that in this type of actuating system the contacting portions of the frames and trackways must be finished with precision and maintained in this condition to insure a smooth sliding action. It will also be apparent that the provision of separate, hydraulically actuated linkages and eccentrically mounted shafts for each frame will be both relatively expensive to construct and a ready source of malfunction.
Of equal importance, it has been found that some degree of play is almost inherent in this type of actuating system and that, almost invariably, when the frames are moved into operative position after a temporary discontinuance of the coating operation, the pressures or spacings between the rolls and the Web, which had been set before discontinuance of the operation, have changed. Hence, upon resumption of coating it is usually necessary to readjust the positions of the rollers until an acceptable coating on the web being treated is obtained. Not only does this result in lost production time, but the web and coating material used in making these adjustments are wasted.
SUMMARY In accordance with the present invention an actuating system is provided which permits the applicator and transfer rolls to be set to their desired operating pressures or spacings. When it becomes necessary to stop the coating operation, the frames on which the rolls are mounted are pivoted rearwardly, withdrawing the rolls from the work piece.
Upon resumption of coating, force is applied directly to the transfer roll frame causing it to tilt forward and move the transfer roller evenly toward the applicator roll. An adjustable, lost motion stop engages the transfer roll frame when the transfer roll has moved to the spacing or pressure value with the applicator roll which had been maintained before interruption of the coating operation. When the transfer roller has been moved to its desired position with respect to the applicator roll, continued application of force to the transfer roll frame is transmitted through the stop member to the applicator roll frame causing this frame to tilt forward about its pivot and carry the applicator roll towards the work piece. A second, adjustable, lost motion stop mounted on the base frame then engages the applicator roll frame when that frame has pivoted to a position such that the applicator roll is brought into its desired position with respect to the workpiece.
The two stops and the force applied to the transfer roll frame then serve to maintain the frames, and the rolls carried thereby, in their operative positions until it is again desired to discontinue the coating operation at which time the force applied to the transfer roll frame is relaxed and the frames allowed to pivot rearwardly and Withdraw the rolls from their operative positions.
It will be seen that with the present apparatus the need for precision finished trackways is eliminated.
It will also be seen that by pivoting the frames rather than sliding them, the frames are always moved evenly into and out of position and the danger of the rolls becoming skewed is obviated.
It will also be seen that force need only be applied to the transfer roll frame since that force is also transmitted through the stop members to the applicator roll frame. Thus, the need for separate actuating systems for each roll is eliminated.
Additionally, through the use of pivoted frames and adjustable stops not only are the rather complicated, dual actuating systems replaced, but the rolls are precisely placed in their desired positions with respect to each other and the workpiece.
Further, by use of the lost motion stops, the rolls are moved serially into their respective positions by a single continuous application of force. Thus, the transfer roller is first moved into its desired position with respect to the applicator roll, causing coating to be transferred thereto, then the entire assembly of rolls is moved as a unit until the applicator roll is in its desired position and coating the workpiece.
These and other objects and advantages will become more readily apparent from the following description.
3 BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a vertical cross-sectional view through a printing or coating station embodying principles of the present invention; and
FIGURE 2 is a rear elevational view thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIGURE 1, it will be seen that the coating or printing station comprises a base frame 1, an applicator roll frame 2, and a transfer roll frame 3. Both sides of the printing or coating station are identical and in the following description one side only will be described; it being understood that the opposite side thereof is the same as that described.
Frame 3 carries a pickup roll 4 and a transfer roll 5, rotatably mounted thereon, with the lower portion of the pickup 4 rotating in a pan or tray 6, which will contain a supply of the coating material.
Applicator roll frame 2 is of substantially reversed L- shape, as seen in FIGURE 1, and carries the applicator roll '7 rotatably mounted between its upright legs 8. Positioned adjacent the applicator roll 7 is a backup roller 9, which carries a web 10 of the material to be treated past the printing or coating station. Frame 3 overlies frame 2 and is pivotally attached thereto, as at 11, and frame 2, in turn, is carried by the base frame 1 and is pivotally attached thereto, as at 12, with the axes of all rollers and pivot points parallel to each other.
Adjacent the rear end of frame 1 a cylinder 13 is pivotally attached, as at 15, and slideably receives a piston carrying a piston rod 16, which in turn, is pivotally attached at its outer end to frame 3 by means of a pivot shaft 17 extending between opposite sides of the frame.
As seen in FIGURES 1 and 2, a clevis member 18 is fixed to the rear end of frame 2, by bolts 19 or the like, and has upstanding, spaced, parallel legs 20. An adjustable, lost motion stop 21 is positioned between the upstanding legs 20 of the clevis and is pivotally attached thereto, as at 22. The stop 21 comprises a substantially horizontally extending leg 23 and a substantially vertically extending leg 24, with the leg 23 overlying a rearwardly projecting shoulder 25 of the frame 3. A threaded adjusting member 26 extends through the leg 24 of stop 21 and has a handle 27 for moving the adjusting screw 26 inwardly and outwardly of the leg 24. A lock nut 28 is also provided for locking the adjusting member 26 in position.
Frame 2 is also provided with a rearwardly extending shoulder 29, and, attached to the rear end of base frame 1 is a second clevis member 30, having upstanding legs 31. An adjustable lost motion stop member 21, identical to that described above, is also provided, pivotally mounted between the upstanding legs 31 of clevis 30.
In its inoperative position, frame 2 wil be resting on frame 1 and frame 3 will be resting on frame 2 with the lower surface of arm 23 spaced from the upper surface of shoulder 25 and the upper surface of shoulder 29 spaced from the lower surface of the leg 23 adjacent thereto. In this position, roll 5 will be spaced from roll 7, and roll 7 will be spaced from roll 9 and the web 10 of material carried thereby. The spacing between shoulders 25 and 29 and the respective legs 23 of adjacent stops 21 will be determined by the extent to which the adjusting members are threaded through the legs 24 of the stop members.
With the components of the coater in their inoperative positions, as described above, when it is desired to resume the coating operation, cylinder 13 is pressurized, causing the piston 16 to extend outwardly thereof. This will cause the frame 3 to pivot about point 11 until the upper surface of the shoulder 25 engages the lower surface of adjacent leg 23. At this point the axes of rolls 5 and 7 will be in their desired positions with respect to each other.
Continued extension of the piston 16 from the cylinder 13 will cause the pivoting force applied to the frame 3 to be transmitted by the shoulder 25 and stop member 21 to the frame 2; causing this frame to pivot about point 12. Frame 2 will then pivot about point 12 until the upper surface of its shoulder 29 contacts the lower surface of the adjacent overlying leg 23. At this point, the axes of rollers 7 and 9 will be at their desired spacing and coating or printing will be applied to the web 10.
The rollers 7 and 5 will remain in their operative positions as long as sufficient pressure is maintained in the cylinder 13. When it is desired to temporarily discontinue the coating operation, the pressure in cylinder 13 is relaxed and the frames 2 and 3, and the rolls 7 and 5, respectively, are allowed to move rearawrdly to their inoperative positions. When it is again desired to commence coating, the cylinder 13 is once again pressurized and the rollers 7 and 5 move, as described above, into their former positions.
It will be seen that because the movement of frames 2 and 3 is a pivotal motion, the rolls 7 and 5 mounted thereon will always move with their axes parallel to the original positions thereof and skewing of the rolls is obviated. Additionally, since the stops 21, locked in position by the lock nuts 28, provide a positive stop between adjacent frames, the rolls, when tilted forward, will always move into exactly the same position they occupied prior to interruption of the coating operation.
Thus, not only does the present invention eliminate the complicated dual actuating system of the prior art, but a system is provided which insures that the rolls will be positively moved into and out of their operative positions.
While a preferred embodiment of the invention has been described for purposes of illustration, it will be apparent that modifications thereof will occur to those skilled in the art within the scope of the appended claims.
1. A coating or printing station comprising:
(a) a base frame,
(b) a substantially L-shaped frame overlying said base frame and pivotally attached to said base frame adjacent the intersection of the legs of said L-shaped frame,
(0) an applicator roller rotatably mounted between the upstanding legs of said L-shaped frame,
(d) a transfer roller frame overlying said L-shaped frame and pivotally attached thereto,
(e) a transfer roller rotatably mounted on said transfer roller frame,
(f) the axes of said rollers and the pivotal connections being substantially parallel,
(g) a first clevis member having a pair of spaced upstanding legs mounted on said base frame,
(h) a first L-shaped member pivotally mounted between said legs of said first clevis with one leg of said first L-shaped member extending substantially horizontally in spaced relation to a rearwardly projecting shoulder on said L-shaped frame and the other leg thereof extending substantially vertically in spaced relation to said base frame,
(i) an adjusting screw threaded through said vertically extending legs of said first L-shaped member and hearing at one end against said base frame,
(j) a second clevis member having a pair of spaced upstanding legs mounted on said L-shaped frame,
(k) a second L-shaped member pivotally mounted between said legs of said second clevis with one leg of said second L-shaped member extending substantially horizontally in spaced relation to a rearwardly projecting shoulder on said transfer roller frame and the other leg thereof extending substantially vertically in spaced relation to said L-shaped frame,
(1) an adjusting screw threaded through said vertically extending leg of said first L-shaped member and bearing at one end against said L-shaped frame,
(m) a cylinder pivotally attached at one end to said base frame, and
(n) a piston slideably received in said cylinder and having a piston rod pivotally attached to said transfer roll frame.
2. A coater or printing station comprising:
(a) a first pivotally mounted frame having a roll rotatably mounted thereon,
(b) a second pivotally mounted frame having a roll rotatably mounted thereon,
(c) the axes of said rolls and the pivotal connections of said frames extending in parallel relationship to each other,
(d) a first lost motion stop mounted on said first frame and comprising:
(i) a clevis having a pair of spaced legs,
(ii) a substantially L-shaped member pivotally mounted between said clevis legs with one leg of said L-shaped member overlying a portion of said first frame and the other leg of said L- shaped member overlying a portion of said second frame, and
(e) means for applying a pivoting force to said second frame.
3. The apparatus of claim 2 further comprising:
(a) means for varying the spacing between the legs of L-shaped member and adjacent portions of said frames.
References Cited UNITED STATES PATENTS 2,205,564 6/ 1940 Johnstone 118262 XR 2,281,340 4/1942 Thiele et a1 118262 XR 2,520,768 8/1950 Kunicki 118-262 2,827,010 3/1958 Schaefer 118262 XR WALTER A. SCHEEL, Primary Examiner. ROBERT I. SMITH, Assistant Examiner.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,397 ,675 August 20 1968 John De Ligt It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:
Column 1, line 42, "In this type of operation it is necessary to maintain a" should read sense to cover printing as well as the application of a Column 2, line 32, after "frame" insert a semicolon; line 43, after "operation" insert a semicolon; line 67, after "then" insert a comma. Column 3, line 39, after "21" insert a comma; line 55, "will" should read will Column 4, line 14, "rearawrdly" should read rearwardly line 72, "first" should read second Signed and sealed this 3rd day of March 1970.
WILLIAM E. SCHUYLER, JR.
Commissioner of Patents Edward M. Fletcher, Jr.