US3130438A

US3130438A - Doctors for rolls

Info

Publication number: US3130438A
Application number: US218490A
Authority: US
Inventors: Charles R Hughes
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-08-20
Filing date: 1962-08-20
Publication date: 1964-04-28
Anticipated expiration: 1981-04-28

Description

April 1954 c. R. HUGHES 3,130,438

' DOCTORS FOR ROLLS Filed Aug. 2-0, 1962 2 SheetsSheet 1 23 INVENTOR.

CHARLES R. HUGE [J BY Mow/4m 5% V Zbw JUUEWFKC April 28, 1964 c HUGHES 3,130,438

DOCTORS FOR ROLLS Filed Aug. 20, 1962 2 Sheets-Sheet 2 INVENTOR. CHARLES P. HUGHES ZLZ M w w A TTOPNE V5 United States Patent 3,130,438 DOCTORS FDR ROLLS Charles R. Hughes, 195 Burgess Drive, Galesburg, Mich. Filed Aug. 29, 1962, Ser. No. 218,490 Claims. (Cl. -25653) This invention relates in general to an apparatus, including doctor blades, for removing unwanted materials which are deposited upon the peripheral surface of a roll and, more importantly, to a type of such apparatus which is more efficient and effective than those previously used. This application is a continuation-in-part of my copending application Serial No. 70,010, filed November 17, 1960, and entitled Doctors for Rolls, now abandoned.

It is well known that doctors or doctor blades have long been used in association with the rolls of various web forming machines, such as papermaking machines or various ones of the machines for producing plastic films. Each doctor is usually comprised of an elongated blade which engages the peripheral surface of a selected roll in the webmaking machine for the purpose of removing therefrom small particles which may be deposited by the web as it moves over the rolls. If these particles are not removed, they will often cause the machine to produce a defective Web.

In order to facflitate a full disclosure of the invention, reference is made herein to the use of one embodiment of the invention in association with the rolls of a papermaking machine. However, it will be recognized that such reference is for illustrative purposes, only, and is not intended to limit the scope of the invention.

Where a papermaking machine is involved, for example, the web of paper moves around one side of the roll and the doctor blade is mounted so that it engages the opposite side of the roll. It is customary to place a plurality of such rolls in vertical stacks with adjacent rolls in tangential engagement. Accordingly, a plurality of doctors may be required, said doctors being mounted for engagement with selected rolls in the stack. The doctors, which are often mounted upon the end structures which support the rolls, are arranged for movement lengthwise of the rotational axes of the rolls which they engage. This lengthwise movement of the doctors loosens, or at least moves, deposits of foreign materials, which often collect along the engaging edge of the blade and thereby prevents annular scoring of the roll by those deposits which are abrasive. These concepts are well known in the art and have been used for many years. However, the existing mechanisms for effecting the lengthwise movement of the doctors have been cumbersome, difiicult to maintain, expensive to install and even more difficult to adjust and to keep in adjustment.

Accordingly, a primary object of this invention has een the provision of an improved apparatus, including a doctor, for effectively removing foreign materials from the peripheral surface of a roll.

A further object of this invention has been the provision of apparatus, as aforesaid, including a plurality of doctor blades arranged respectively in association with a plurality of rolls and including improved, eflicient mecham'sm for effecting lengthwise movement of said doctor blades.

A further object of this invention has been the provision of an apparatus, as aforesaid, wherein the reciprocating movements of the several doctor blades are out of phase with each other in order to reduce the radial load upon the driving mechanism, and wherein the amount of lengthwise movement of said doctors can be quickly and easily adjusted.

A further object of this invention has been the provision of an apparatus, as aforesaid, which is relatively simple 3,130,438 Patented Apr. 28, 1964 in construction which is completely foolproof in its operation, which requires a minimum of cost to manufacture and operate and which is more effective and efiicient in operation than previous devices for the same or similar purposes.

Other objects and purposes of this invention will become apparent to persons familiar with this type of equipment upon reading the following descriptive material and examining the accompanying drawing, in which:

FIGURE 1 is a side elevational view of an apparatus, including a plurality of doctors, embodying the invention.

FIGURE 2 is an end elevational view of said apparatus.

FIGURE 3 is a broken sectional View taken along the line III III in FIGURE 1.

FIGURE 4 is a sectional View taken along the line lV-IV in FIGURE 1.

FIGURE 5 is a sectional view similar to that shown in FIGURE 4 with the parts in difierent positions of operation.

FIGURE 6 is a sectional View taken along the line VI-VI in FIGURE 1.

FIGURE 7 is a sectional view taken along the line VII-VII in FIGURE 1.

FIGURE 8 is a fragment of an apparatus similar to the apparatus shown in FIGURE 1, and disclosing an alternate structure for doctors embodying the invention.

FIGURE 9 is a sectional view substantially as taken along the line IXIX in FIGURE 8.

FIGURE 10 is a sectional view substantially as taken along the line XX in FIGURE 8.

FIGURE 11 is a sectional view taken along the line XIXI in FIGURE 10.

For convenience in description the terms upper, lower, left, right, front, rear and words of similar import, will have reference to a machine embodying the invention and the structure associated therewith as appearing in FIGURE 1, which discloses the front view of the machine in its normal position of operation. The terms inner, outer and derivatives thereof will have reference to the geometric center of said machine and parts associated therewith.

General Description The objects and purposes of the invention, including those set forth above, have been met by providing an apparatus including a plurality of doctors which are mounted in association with an equal number of rolls for the purpose of engaging the peripheral surfaces of said rolls and thereby removing foreign materials from said surfaces. In a preferred embodiment, the doctors, which include elongated roll-engaging blades, are mounted upon the end structures which support the rolls. Corresponding ends of the doctors are engaged by cam actuated devices which effect lengthwise reciprocation of the doctors. The cams are mounted upon a shaft so that the lengthwise reciprocations of at least some of the doctors are out of phase with each other. This reduces the radial loads upon the bearings supporting the cam shaft, which may be driven by a motor operating through a gear box.

The throw of each cam is preferably adjustable so that the reciprocations of the doctors may be varied. The doctor blades are resiliently urged against their respective rolls which, in this particular embodiment, are arranged in a vertical stack as part of a papermaking machine.

Detailed Construction The part of a machine 10, shown in FIGURE 1, has a stack of parallel rolls I1, 12 and 13 which are rotatably supported upon and between the end structures 16 and 17. The apparatus 18 of the invention includes a plurality of elongated doctors 19 and 19a supported upon the end structures 16 and 17, and mechanism 22 connected to said doctors for reciprocating same lengthwise thereof.

In this particular embodiment of the invention, the upper end and lower rolls 11 and 13, respectively, are calendar rolls separated by and engaged with an intermediate roll 12. The web 23 of paper passes around the rear sides of the rolls 11 and 13 and around the front side of the intermediate roll 12. The doctors 19 and 19a are located along the front sides of said rolls 11 and 13. The

rolls

11, 12 and 13 are mounted upon the end structures 16 and 17 by means such as the bearings 24. The calendar rolls 11 and 13 may be interconnected and appropriately driven by means indicated schematically in broken lines at 26 in FIGURE 1.

The doctor 19 (FIGURES 1, 3 and 6) includes a substantially rigid, support rod 27, which is preferably circular in cross section. Said rod 27 is mounted upon the end structures 16 adjacent the front side of the roll 11 by means of the

bearings

28 and 28a which permit both rotational and axial movement of the rod 27 with respect thereto. Two or more sleeves 32 (FIGURE 6) are mounted at spaced intervals upon the rod 27 and are releasably held thereon by means, such as a set screw 33. A doctor blade 34, which has a roll-engaging edge 36, is mounted upon the sleeve 32 and preferably extends substantially beyond both ends of the roll 11. Said doctor blade 34 has a pair of transverse slots 37 extending therethrough. Screws 38 slidably extend through the slots 37 for threaded engagement with the sleeves 32, whereby said blade 34 is adjustably secured to the sleeves 32.

The doctor blade 34 (FIGURE 3) has a pair of

integral fingers

41 and 42 extending from opposite lengthwise ends thereof adjacent to the edge 36. A pair of resilient elements, such as the spiral springs 43 and 43a, are secured at one encLof each to the

fingers

41, 42, respectively. The other ends of said springs 43 and 4312 are connected respectively to the brackets 46 and 47 (FIGURE 3) mounted upon the end structures 16 and 17, respectively. The springs 43 and 43a are under tension when the edge 36 of the blade 34 is in engagement with the roll 11.

The doctor 19a, in this particular embodiment, may be substantially identical in structure to the doctor 19 so that a detailed description of the doctor 19a is unnecessary. Briefly, the doctor 19a includes a rod 27a which is supported upon and between

bearings

29 and 29a, which are mounted upon the end structures 16 and 17, respectively. The doctor blade 34a is mounted upon the rod 27a, as set forth above with respect to the doctor blade 34, and it has an edge 36a which is engageable with the peripheral surface of the calendar roll 13. The edge 36a of the doctor blade 34 is held against the roll 13 by means including the springs 44 and 44a.

The drive mechanism 22 (FIGURES 1 and 2) includes a substantially vertical shaft 51, the lower end of which is connected to, and is rotatably supported upon, the output end of the gear box 52. The upper end of the shaft 51 is rotatably supported within a bearing 53 mounted upon the end structure 16 by means of a bearing support 54. The gear box 52 is connected to a convenient drive means, such as the motor 56.

A cam 57 (FIGURES 4 and is mounted upon the vertical shaft, 51 adjacent the extended leftward end of the rod 27. In this particular embodiment, the cam 57 is circular and it has a circular, eccentric opening 58 in which a circular adjustment member 59 is snugly, but rotatably and slidably, disposed. Said member 53 has an eccentric shaft opening 62, through which the shaft 51 is snugly received. The eccentricity of the shaft openings 62 is preferably identical to the eccentricity of the adjustment opening 58 whereby the eccentricity of the cam 57 can be adjusted in any amount from maximum eccentricity, as shown in FIGURE 4, to concentricity, as shown in FIGURE 5. The adjustment member 59 is releasably secured upon the shaft 51 by a set screw 63, and the cam 57 is releasably mounted upon the adjustment member 59 by a set screw 64.

The peripheral surface of the cam 57 is engaged by, and between, the arms 66 and 67 (FIGURES 3, 4 and 5) of a yoke 68, the stem of which is in the form of a sleeve 69 from which said arms extend. The sleeve 69 is mounted upon the leftward end of the rod 27 and secured thereto by means including a set screw 71. A pair of wear plates 72 (FIGURE 4) are mounted upon the opposing surfaces of the

arms

66 and 67 for engagement with the cam 57.

The shaft 51 is drivingly connected to the rod 27a of the doctor 19a by a cam 57a and yoke 68a which may be arranged and constructed like the above-described cam 57 and yoke 68.

. Operation In preparing the apparatus 18 for operation, the angle of the blade 34 with respect to the roll 11 may be altered by loosening the screws 38 and shifting the doctor blade transversely of its rod, as may be required, after which said screws are tightened. The screw 71 is then loosened and the yoke 68 is readjusted upon the rod 27 so that the cam 57 is properly aligned between the

arms

66 and 67. The amplitude of the lengthwise reciprocation of the doctor blade 19 can be adjusted by loosening one or both of the

set screws

63 and 64 and adjusting the cam 57 or its adjustment member 59 or both, as may be required. Adjustment of the blade 34a or the cam 57a may be effected in a similar manner.

Under normal circumstances, and according to the teachings of the invention, it will be desirable to arrange the

cam

57 and 57a, as well as the adjustment members 59 therein, so that the throws or maximum eccentricities of said cams are arranged uniformly around the vertical am's of the shaft 51. That is, where two

cams

57 and 57a are involved, for example, the maximum eccentricities thereof will be in opposite radial directions or 180 out of phase. Where three cams are provided, then the eccentricities would preferably be arranged at 120 intervals around the shaft axis. In the same manner, four cams would be arranged so that their maximum eccentricities would be at intervals around the shaft axis. Thus, the complete rotating unit, including the vertical shaft and the cams mounted thereon, can be arranged in dynamic balance. Moreover, the reciprocations of the various doctor blades will be phased so that the wear upon the hearing 53 and the gear box 52, due to radial thrust, will be held to a minimum. Furthermore, phasing of the reciprocations of the doctors tends to minimize sympathetic vi brations in the machine 10 and also permits the use of lighter duty, hence less expensive drive mechanism 22.

With the apparatus 18, including the doctors 19 and 19a, and the drive mechanism 22, assembled upon the machine .10 as shown in FIGURE 1 and properly adjusted as discussed above, operation of the machine 10 is commenced by the drive means 26. Thereafter, the operation of the apparatus 18 is initiated by energizing the motor 56 which causes the gear box 52 to rotate the shaft 51 and the

cams

57 and 57a thereon whereby the

yokes

68 and 68a, hence the

rods

27 and 27a, are reciprocated lengthwise of the rolls 11 and 13. The edges 36 and 36a are resiliently urged against the peripheral surfaces of the rolls 11 and 13 by the

springs

43, 43a, 44 and 44a for the purpose of removing undesirable materials deposited thereon during the normal operation of the machine 10 in producing the web 23.v

Alternate Construction The alternate matchine 10a includes three rolls 11a, 12a and 13a which may be substantially the same as the

rolls

11, 12 and 13, respectively, in the machine 10 of FIGURE 2. A fourth roll 76 is shown below the roll 13:: in the alternate machine 10a. The doctors 77 and 77a, in the alternate apparatus 78 of the invention, are operatively associated with the rolls 11a and 13a, respectively, to

5 perform the same function as set forth above with respect to the doctors 19 and 19a.

The apparatus 78 also includes the drive mechanism 79 which functions in much the same manner as the drive mechanism 22 in the apparatus 18. That is, a vertical shaft 51a is rotatably mounted upon the end structure 16a by bearings 53a and the associated bearing supports 54a. The vertical shaft 51:: is connected at its lower end through the gear box 52a to the motor 56a. The rolls 11a, 12a, 13a and 76 are supported upon the end structure 16a by bearings 82.

The doctor 77, for example (FIGURE 11), includes an elongated structure member 83 having lengthwise

flanges

84 and 85. An elongated doctor blade 87 is supported by the bolts 88 upon, and lengthwise of, the flange 85 so that one lengthwise edge 90 of the blade 87 engages the surface of the roll 11a. The doctor blade 87 has transverse slots 89 through which the bolts 88 extend for efiecting transverse adjustment of the blade toward and away from the roll 11a. In this particular embodiment, the blade 87 is comprised of a relatively soft strip 91 which includes the edge 90, and a relatively stiff back plate 92, which holds the soft strip 91 in position with respect to and adjacent the flange 85. This type of blade is particularly useful with a roll of the type having a fibrous or non-metallic surface. The soft strip 91 may, for example, be fabricated from felt or the like.

The angle member 83 has at its opposite ends shaft means, such as the stub shaft 93 shown in FIGURES l and 11, which extend from the opposite ends of the angle member and substantially parallel therewith. The stub shaft 93 is rotatably and axially slidably supported within a bearing 94, which is in turn supported by the bearing bracket 96 upon the end structure 16a. Accordingly, the stub shaft 93, hence the doctor 77, can rotate around and move lengthwise of the common axis of the stub shaft 93 and bearing 94.

A cam follower 97, having a yoke 93, is adjustably mounted upon the flange 84 of the angle member 83 for engagement with a cam 99 supported upon the vertical shaft 51a. The cam 99 may be identical with the cam 57 of the apparatus 18 (FIGURES 4 and 5). If the shaft 51a is rotated when the cam 99 is eccentric with respect thereto, said cam will operate through the cam follower 97 to effect a lengthwise reciprocation of the doctor 77, just as rotation of shaft 51 (FIGURE 3) acts through cam 57 to reciprocate the doctor 19.

The soft strip 91 of the doctor blade 87 is yieldably and adjustably urged against the roll 11a (FIGURES 9 and 10) by a counterweight 162 which is connected to the angle member $3 by the support rod 103. More specifically, the rod 103 is rigidly mounted at one end thereof upon the flange 84 so that said rod extends upwardly and outwardly from the member 83 and roll 11a. The counterweight 102 is slidably supported upon the rod 193 for adjustment lengthwise thereof. A set screw 194 is provided for holding the counterweight in a selected position lengthwise of the support rod 103. The blade 87 is arranged so that it is urged upwardly against the roll 11a by the downward urging of the counterweight 1'92. Accordingly, by appropriate location of the counterweight 102 along the support rod 163, adjustments can be made in the amount of pressure with which the soft strip 91 is pressed against the periphery of the roll 11a.

The doctor 77a (FIGURE 8) may be and preferably is identical to the doctor 77 in construction and in operation. More specifically, the doctor 77a includes an angle member 83a supporting a doctor blade 37:: having a soft strip 91a which is yieldably urged against the roll 13a by a counterweight 192a mounted upon a support rod 103a, which is rigidly connected to the angle member 83a. A cam follower 97a, which is connected to the angle member 8301, engages a cam 99a mounted upon the vertical shaft 61a for effecting lengthwise reciprocation of the doctor 77a. The

cams

99 and 99a are preferably mounted upon the vertical shaft 51a so that their eccentricities are in dynamic balance around the axis of the shaft, thereby minimizing the adverse effects of their eccentricities upon the bearings 53a. The operation of the apparatus 78 is substantially the same as the operation of the apparatus 18, even though the pressure control provided by the counterweights 102 and 102a and the construction of the doctors 77 and 77a differ somewhat from their corresponding elements in the apparatus 13. Moreover, in many situations, the apparatus 78 is interchangeable with the apparatus 18, insofar as the purpose of operation and acceptability of performance are concerned.

Although particular, preferred embodiments of the invention have been disclosed herein for illustrative purposes, it will be understood that variations or modifications of such disclosure, which lie within the scope of the appended claims, are fully contemplated.

What is claimed is:

1. An apparatus for removing materials from the peripheral surface of a rigid cylindrical device rotatably mounted upon and between a pair of support structures, comprising:

an elongated, substantially rigid member having lateral edge means engageable with said peripheral surface, said rigid member including first shaft means secured to, and extending from the opposite ends of, said rigid member;

bracket means mounted upon said support structures,

said first shaft means being engaged and supported by said bracket means for axial movement with respect to said bracket means, said bracket means being arranged so that said edge means on said rigid member can move toward and away from a position wherein said edge means is in engagement with, and extends substantially the full length of, the peripheral surface of said cylindrical device;

means secured to said rigid member for continuously urging said edge means of said rigid member against said peripheral surface;

an eccentric;

second shaft means rotatably supporting said eccentric near said rigid member;

adjustment means connected to said eccentric for changing the eccentricity thereof with respect to said sec ond shaft means;

follower means engaged by said eccentric and rigidly connected to said rigid member; and

drive means connected to said second shaft means for rotating same, whereby said eccentric is rotated and said follower means effects a lengthwise reciprocation of said rigid member.

2. The structure of claim 1 wherein said substantially rigid member includes a relatively rigid and elongated back plate and an elongated relatively soft strip defining said lateral edge, said soft strip being adjustably held with respect to said rigid member by said back plate for adjustment transversely of the lengthwise extent of said rigid member, whereby said lateral edge means can be adjusted with respect to the peripheral surface of the cylindrical device.

3. An apparatus for removing materials from the peripheral surface of a cylindrical member rotatably mounted upon and between a pair of support structures, comprismg:

an elongated, substantially rigid member having lateral edge means engageable with said peripheral surface; first shaft means secured to, and extending from the opposite ends of, said rigid member;

bracket means mounted upon said support structures,

said first shaft means being snugly engaged and supported by said bracket means for axial movement with respect to said bracket means, said bracket means being arranged so that said edge means on said rigid member can move toward and away from a position wherein said edge means is in engagement with and extends substantially the full length of the peripheral surface of said cylindrical member;

yieldable means secured to said rigid member for continuously urging said edge means of said rigid member against said peripheral surfaces;

an eccentric;

second shaft means rotatably supporting said eccentric close to said first shaft means;

adjustment means connected to said eccentric for changing the eccentricity thereof with respect to said second shaft means;

follower means engaged by said eccentric and mounted upon said first shaft means; and

4. An apparatus for removing foreign materials from a the peripheral surfaces of a plurality of rolls supported upon and between a pair of upright structures, said rolls being axially horizontal and vertically aligned, comprising:

a plurality of elongated, parallel and substantially rigid rods one of said rods being disposed adjacent the peripheral surface of each roll and extending lengthwise thereof;

a plurality of bearing members arranged in coaxial pairs and mounted upon said support structures, the opposite end portions of each rod being disposed within a pair of said bearing members for rotational and axial movement with respect thereto;

a plurality of elongated doctor blades, one blade being mounted upon each rod for movement therewith, each blade having an elongated edge engageable with the peripheral surface of the adjacent roll substantially throughout the length thereof;

resilient means connected between one of said support structures and the adjacent end of each blade for urging said edge against said peripheral surface;

parallel arms engaging the opposite sides of one of said cams, whereby rotation of said shaft effects lengthwise sequential reciprocation of said rods and said doctor blades; and drive means connected to said shaft for eflYecting rotation thereof. 5. The structure of claim 4 wherein each cam is comprised of a pair of substantially cylindrical members having eccentrically disposed, circular openings therethrough,

the central axes of said openings being respectively parallel with the central axes of said cylindrical members, one member being rotatably and snugly disposed within the circular opening in the other member and the eccentricities of said openings being substantially the same, whereby the amount of eccentricity of the outer member with respect to said shaft, which extends through the opening in the inner member, can be adjusted by rotating one of said members with respect to the other; and

screw means within each member whereby said outer member can be rigidly held with respect to the inner member and the inner member can be positively secured upon said shaft.

Berry et al. Mar. 12, 1929 Edmondson July 13, 1943

Claims

1. AN APPARATUS FOR REMOVING MATERIALS FROM THE PERIPHERAL SURFACE OF A RIGID CYLINDRICAL DEVICE ROTATABLY MOUNTED UPON AND BETWEEN A PAIR OF SUPPORT STRUCTURES, COMPRISING: AN ELONGATED, SUBSTANTIALLY RIGID MEMBER HAVING LATERAL EDGE MEANS ENGAGEABLE WITH SAID PERIPHERAL SURFACE, SAID RIGID MEMBER INCLUDING FIRST SHAFT MEANS SECURED TO, AND EXTENDING FROM THE OPPOSITE ENDS OF, SAID RIGID MEMBER; BRACKET MEANS MOUNTED UPON SAID SUPPORT STRUCTURES, SAID FIRST SHAFT MEANS BEING ENGAGED AND SUPPORTED BY SAID BRACKET MEANS FOR AXIAL MOVEMENT WITH RESPECT TO SAID BRACKET MEANS, SAID BRACKET MEANS BEING ARRANGED SO THAT SAID EDGE MEANS ON SAID RIGID MEMBER CAN MOVE TOWARD AND AWAY FROM A POSITION WHEREIN SAID EDGE MEANS IS IN ENGAGEMENT WITH, AND EXTENDS SUBSTANTIALLY THE FULL LENGTH OF, THE PERIPHERAL SURFACE OF SAID CYLINDRICAL DEVICE; MEANS SECURED TO SAID RIGID MEMBER FOR CONTINUOUSLY URGING SAID EDGE MEANS OF SAID RIGID MEMBER AGAINST SAID PERIPHERAL SURFACE;