US3167470A - Paper machine headbox with adjustable slice - Google Patents

Description

Jan. 26, 1965 L. A. MOORE 3,167,470

PAPER MACHINE HEADBOX WITH ADJUSTABLE SLICE Filed March 17, 1961 2 Sheets-Sheet l IN VEN TOR.

LAWRENCE A. MOORE wwwwf ATTORNEYS Jan. 26, 1965 1.. A. MOORE 3,167,470

PAPER MACHINE HEADBOX WITH ADJUSTABLE SLICE Filed March 17, 1961 2 Sheets-Sheet 2 INVEN TOR. LAWRENCE A. MOORE ATTORNEYS if x s,1e7,470 PAPER MACHINE HEADBOX WlTH ADJUSTABLE SLECE Lawrence A. Moore, Beloit, Wis, assignor to The Black- Clawson Qompany, Hamilton, Ohio, a corporation of Shin Filed 17, 1961, Ser. No. 96,503 4 Claims. (Cl. 162-347) This invention relates to paper making machines, and more particularly to a headbox for a Fourdrinier paper machine.

The invention is directed to the provision of a headbox for use in combination with a Fourdrinier paper machine capable of operating over a range of wire speeds which includes very high speeds requiring a high spouting velocity of the stock and correspondingly high pre sure effective on the stock within the headbox. The invention is especially concerned with the provision of a headbox structure which is capable of delivering stock to the forming wire at high velocity and a high volumetric rate of fiow and also with an accurately controlled flow across the entire width or" the wire in all adjusted positions of the slice opening.

It is a primary object of the invention to provide a headbox for the purposes outlined above wherein the upper slice lip is of novel construction providing for adjustment in both vertical and horizontal directions and wherein each rectifier roll mounted adjacent the slice lip is equipped with adjustable mountings of novel construction assuring that it can be adjusted to the position for optimum effectiveness with respect to the upper slice lip and the bottom wall of the headbox in all adjusted positions of the slice lip.

It is particularly an object of the invention to provide a headbox as outlined above wherein a novel construction and combination of the upper slice lip and a footwalk extending above the forming wire assures maximum rigidity of the slice lip in all its adjusted positions and minimum tendency for vibrations in the stock supply system to produce variations in the contour of the slice opening.

Additional objects and advantages of the invention will be apparent from the following description, the accom panying drawings and the appended claims.

In the drawings FIG. 1 is a somewhat diagrammatic view in vertical section showing a headbox constructed in accordance with the invention;

FIG. 2 is a fragment of FIG. 1 showing a moved position of the upper slice lip and associated rectifier rolls;

FIG. 3 is an enlarged fragment of FIG. 1 showing details of the slice lip construction;

FIG. 4 is fragmentary and somewhat diagrammatic front view of the headbox of FIG. 1;

PEG. 5 is a fragmentary side elevation of the headbox of FIGS. 1-4 looking from right to left in FIG. 4;

FIG. 6 is an enlarged section on the line 6-6 of FIG. 5 showing details of the adjustable mounting for the lower rectifier roll; and

FIG. 7 is a section on the line 77 of FIG. 6.

Referring to the drawings, which illustrate a preferred embodiment of the present invention, the flow chamber of the headbox is defined by a front wall Iii, side walls 11 and 12, a bottom wall 13, and a wall 15 which extends in a continuous curve from the front wall to form both the top and back walls of the headbox. Bracing ribs 16 extend around a substantial portion of the outside of the wall 15. The wall also is provided at the top with a port 17 equipped with a sealing cover 18.

The front wall It includes the upper slice lip 20 which is secured as by bolts 21 to the lower edge of the wall 10 and cooperates with the lower slice lip 22 at the front of the bottom wall 13 to define a slice outlet 23 through which the stock is discharged onto the forming wire 24 as it passes over the breast roll 25. The slice lip 20 is adjustable horizontally as described in detail hereinafter, and it is adjustable vertically with the front wall 10, which is suspended for vertical sliding movement from the dome which forms a rigid framework extending across the front of the headbox above the front portion of the wall 15. More specifically, the wall it depends from the screw members 31 of a plurality of jacks 33 each of which is mounted by a bracket 34 on top of the dome 30. The drive shafts 35 for all of the jacks 33 are provided with a common drive (not shown) such as a hand wheel or motor.

The inlet portion of the headbox through which the stock enters the interior of the headbox includes a distribution chamber into which stock is delivered by a plurality of supply pipes 41 connected in spaced relation across the back of the headbox. From the distribution chamber 40, the stock flows upwardly through a narrow inlet throat 42, and the inlet passage 44 defined by walls 45 and 46 above the throat 42 diverges upwardly to form a venturi passage leading directly into the back of the headbox. A rectifier roll d8 is mounted within the upper portion of the venturi passage 44 to quiet turbulence in the stock as it emerges from the throat 42 and flows upwardly into the interior of the headbox.

As shown, the headbox of the invention is totally enclosed in the top but is designed to operate with an air space within its upper port and above the level of stock flow therethrough, and a connection 50 is provided in one of the side walls for attachment to a suitably controlled source of air pressure. A plurality of shower pipe 51 are also provided in the top of the headbox for continuously showering the top of the stock flowing through the box to minimize the possibility of the development of foam. The control system for regulating the stock level within the box and the air pressure may be constructed, for example, as described in the copending application of Corbin, Moore and Pearson, Serial No. 746,450 filed July 3, 1958 and assigned to the same assignee as this application, which is a continuation in part thereof. Alternatively, manual controls for the stock supply and air pressure may be provided in conjunction with a conventional air pressure gauge and sight glass in one side wall of the headbox.

The stock enters the back of the headbox with an upward flow and at relatively high velocity when the paper machine is operated at high volumes, and it is therefore necessary to operate with a substantial level of stock within the box in order to establish desired uniformity of flow conditions before the stock is discharged onto the forming wire. Since this in turn requires substantial deceleration of the flow rate, it is usually found necessary to provide rectifier means at an intermediate position in the box for the purpose of preventing floculation or settling of the fibers as the stock flows toward the front of the box. A single rectifier roll 55 of relatively large diameter, for example 24 inches, is shown in FIG. 1 for accomplishing this result. It is also possible in the practice of the invention to employ multiple rectifier rolls arranged in staggered, overlapped relation as disclosed in the above Corbin et al. application.

It is also usually found necessary for optimum results to provide rectifier means adjacent the slice outlet of a headbox for the purpose of subduing eddies which might otherwise cause non-uniform sheet formation. FIG. 1 shows a pair of rectifier rolls and 61 arranged for this purpose, the roll 60 being positioned in closely spaced relation with the bottom wall 13, and the roll (B 61 being positioned in vertically spaced and overlapping relationship with the roll 61 and in closely spaced relation with both the roll and with the upper slice lip 20. It will also be noted that the spacing of the rolls 6t) and 61 is non-uniform with respect to the outlet opening 23, and preferred results are obtained when the arrangement of the rolls is such that a plane passing between the rolls at right angles to the plane containing their axes will intersect the bottom slice lip at a location spaced substantially rearwardly from the slice opening 22.

Special provision is made in accordance with the invention for establishing assured rigidity in the upper slice lip 20 while at the same time making it possible to adjust the lower end of the slice lip generally horizontally. This is particularly important for a variety of reasons. For example, any variation in absolute straightness and smoothness of the discharge lip will be reflected in nonuniform formation of the sheet. In addition, any vibrations or pulsations in the stock supply system must be subdued to the maximum extent before the stock reaches the wire, and it is important from this standpoint to have maximum assurance that the upper slice lip will not vibrate or otherwise be subjected to deflection, especially non-uniform deflection, during operation of the machine.

The above objectives are accomplished in accordance with the invention by a novel construction and combination of the upper slice lip 20 with the footwalk 65 which extends across the front of the head-box above the forming wire. The footwalk itself comprises a trough-shaped section of sheet metal of substantial rigidity, and it is provided with a hand rail 66 extending along its forward side. The footwalk 65 is mounted on and rigidly secured to the front of the upper slice lip 20 by means of a plurality of generally L-shaped brackets 67 which are located in relatively closely spaced relation across the full width of the headbox, satisfactory results have been obtained with these brackets spaced on 15 inch centers. Additional rigidity is contributed to the slice slip by a plate 68 supported on the upper ends of the brackets 67 and welded thereto and to the slice lip.

The plate 68 also serves as a support for the mechanism for adjusting the extension member 70 which forms the lower edge of the slice lip 20. Referring particularly to FIG. 3, the extension member 70 extends the full width of the slice lip 21? and is supported for vertical adjustment thereon by means of a plurality of clamp blocks 71 each provided with a clamp screw 72. Each of the clamp blocks 71 is in turn controlled by an adjusting screw 75 depending from and controlled by an adjusting knob 77 carried by the plate 68. This arrangement provides for adjustment ,of the lip extension '70 to a position of absolute straightness and parallelism with the lower slice lip 22 which is thereafter maintained in all adjusted positions of the slice lip 2%.

As already noted, provision is made for horizontal adjustment of the slice lip 20, by causing it to pivot or warp about a thin section 80 which extends across its full width near its upper edge or point of attachment to the front wall 10. The means for causing this movement includes a pair of turnbuckles 81, one at each side of the headbox. As best seen in FIG. 5, one end of the turnbuckle 81 is provided with a pivotal mounting 82 on the side wall 11, and the other end of the turnbuckle is pivoted in a clevis bracket 83 secured to the underside of the footwalk 65. It will thus be apparent that adjustment of the turnbuckles 81 will cause the entire slice lip assembly, including the footwalk 65 to move generally horizontally and thereby to swing the lower end of the slice lip forward and backward. Throughout all such adjusting movement, the footwalk and its mounting brackets maintain the rigidity of the It is important for optimum production that the rectifier rolls 6t and 61 always be in the closest possible relation with each other and with the bottom wall 13 and slice lip 21), in order to minimize the delivery of unrectified stock to the outlet, but it is at the same time essential to prevent frictional contact therebetween. It is also important that the non-uniform spacing of these rolls from the outlet be maintained in all their adjusted positions. The invention provides special mounting means for achieving these results.

Referring particularly to FIGS. 57, each of the journals 88 of the rectifier rolls 60 is mounted in a bearing bracket $11 having an eccentric bore 91 in which the journal 88 is rotatably supported by a bushing 92. The outer end of the bracket is formed with a transverse slot 93 having an inner end face 94 surrounding the bore 91, and the outer end of this how is sealed by packing 95 and a gland 96 bolted to the face 94. A flange mounting bracket 97 is bolted to the outer end of the bracket 90 to form an end cover therefor.

The bearing bracket 90 includes a cylindrical inner end portion 99 which extends through a complementary bore in a base plate 100, and through a complementary horizontal slot 101 in the side wall 11. The bracket 90 is normally secured to the plate 100 by a pair of arcuate clamps 103, and when these clamps are loosened, the

bracket 90 can be rotated in the plate 161). Since the bore 91 is eccentric with respect to the bracket portion 99, such rotation will have the effect of moving the journal $8 in an arcuate path and thereby locating the roll 6% in the desired closely spaced relation with the bottom wall 13.

The slot 101 in the side wall 11 permits horizontal movement of the bearing bracket 90 for horizontal adjustment of the roll 61). This slot is sealed on the inside of the wall 11 by a seal plate 105 secured as by screws 106 to the inner end of the housing 90. The plate 100 carries screws 107 which can be threaded against the outer surface of a reinforcing plate 108 on the side wall 11 to draw the seal plate 102 tightly against the inner surface of the wall 11, and the screws 107 are loosened when it is desired to adjust the roll 60.

The horizontal movement of the bearing housing 90 is effected and controlled by an adjusting screw 110 which is secured to the bore plate 100 at 111 and passes through a bore in the side wall reinforcing rib 113. Look nuts 114 and 115 are operable alternately to move the screw 110 and to secure it in moved position, and FIG. 5 shows a convenient means for measuring the movement of the roll as comprising a pointer 116 carried by the movable bearing assembly and cooperating with a scale 117 on the sidewall 11.

The mounting for each journal of the roll 61 includes a sliding bearing housing 120 similar to the housing 90 except that the bore therein for the roll journal is not eccentrically locatedbecause there is no reason to change the vertical position of the roll 61. The horizontal movement of the housing 121) is effected similarly to that of the housing 90, by a screw 123, lock nuts 124 and 125, and a cooperating bracket 126 secured to the side wall 11. Under normal conditions, the vertical adjustment of the roll 60 is made at the time of installation of the box, and need not thereafter be changed. The roll 61 is adjusted horizontally to close running relation with the slice lip 20 in each adjusted position of the latter, and the roll 60 is then similarly adjusted horizontally into the proper closely spaced relation with roll 61.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A head box for a paper making machine comprising a pair of side walls cooperating with bottom and back Walls and with front wall means to define a flow chamber, said front wall means including a front wall member secured in rigid relation with said top wall and an upper slice lip of rigid construction carried by said front wall member in depending relation therewith and cooperating with said bottom Wall todefine a slice outlet from said chamber, said front wall means also including a thin section extending horizontally thereacross and of substantially less thickness than said slice lip to provide for forward and backward swinging movement of said slice lip while maintaining said lip in sealed relation with said front wall member, means forming an inlet for stock at the back of said chamber to provide for generally horizontal flow of the stock toward said slice lip for discharge through said outlet, a pair of rectifier rolls located adjacent said outlet in non-uniformly spaced relation therewith and in closely spaced relation with each other and with said bottom Wall and slice lip respectively, said thin wall section being located at a higher level than said rectifier rolls, means connected between said slice lip and said side walls for moving said slice lip forward and backward about said thin section, and means mounting said rectifier rolls on said side walls for adjustment substantially parallel with said bottom wall to maintain said spaced relation thereof to each other and to said bottom wall and said slice lip in accordance with the moved position of said slice lip.

2. A head box for a paper making machine comprising a pair of side walls cooperating with bottom and back walls and with front wall means to define a flow chamber, said front wall means including a front wall member secured in rigid relation with said top wall and an upper slice lip carried by said front wall member in depending relation therewith and cooperating with said bottom wall to define a slice outlet from said chamber, said front wall means also including a thin section extending horizontally thereacross and of substantially less thickness than said slice lip to provide for forward and backward swinging movement of said slice lip while maintaining said lip in sealed relation with said front wall member, means forming an inlet for stock at the back of said chamber to provide for generally horizontal flow of the stock toward said slice lip for discharge through said outlet, a pair of rectifier rolls located adjacent said outlet in non-uniformly spaced relation therewith and in closely spaced relation with each other and with said bottom wall and slice lip respectively, said thin wall section being located at a higher level than said rectifier rolls, means connected between said slice lip and said side walls for moving said slice lip forward and backward about said thin section, means mounting said rectifier rolls on said side walls for adjustment'substantially parallel with said bottom wall to maintain said spaced relation thereof to each other and to said bottom wall and said slice lip in accordance with the moved position of said slice lip, a substantially rigid footwalk extending across the front of said head box, and bracket means securing said footwalk in bracing relation directly to said slice lip below said thin section to maintain said slice lip rigidly braced in all adjusted positions thereof.

3. A head box for a paper making machine comprising a pair of side walls cooperating with bottom and back walls and with front wall means to define a iow chamber, said front wall means including a front wall member secured in rigid relation with said top wall and an upper slice lip carried by said front wall member in depending relation therewith and cooperating with said bottom wall to define a slice outlet from said chamber, said front wall means also including a thin section extending horizontally thereacross and of substantially less thickness than said slice lip to provide for forward and backward swinging movement of said slice lip while maintaining said lip in sealed relation with said front wall member, means forming an inlet for stock at the back of said chamber to provide for generally horizontal flow of the stock toward said slice lip for discharge through said outlet, rectifier roll means located adjacent said outlet in closely spaced relation with said bottom wall and slice lip, said thin wall section being located at a higher level than said rectifier rolls, means connected between said slice lip and said side walls for moving said slice lip forward and backward about said thin section, a plurality of generally L- shaped brackets secured directly to said slice lip below said thin section in spaced relation across said headbox with one arm portion of each thereof projecting forwardly from a position adjacent the lower edge of said slice lip to effect vertical bracing of said slice lip, and a substantially rigid footwalk extending across the front of said headbox .and directly secured to said arms of all of said brackets for cooperation with said brackets to effect horizontal bracing of said slice lip.

4. A headbox as defined in claim 3 comprising a plate extending across the front of said slice lip below said thin section and secured in supported relation on the upper end portions of said brackets, and a plurality of adjusting assemblies connected between said lip extension and said plate for regulating the adjusted position of said lip extension on said slice lip.

References Cited in the file of this patent UNITED STATES PATENTS 292,047 Recker Ian. 15, 1884 1,818,777 Aldrich et al Aug. 11, 1931 1,906,355 Bagley et al May 2, 1933 2,022,298 Neilson Nov. 26, 1935 2,186,761 Malkin Ian. 9, 1940 2,225,435 Kellett et al Dec. 17, 1940 2,351,656 Auten June 20, 1944 2,615,374 Malkin Oct. 28, 1952 2,747,471 Corbin et a1. May 29, 1956 2,749,815 Stewart June 12, 1956 3,019,486 Stinson Feb. 6, 1962 FOREIGN PATENTS 464,219 Canada Apr. 4, 1950

Claims (1)

1. A HEAD BOX FOR A PAPER MAKING MACHINE COMPRISING A PAIR OF SIDE WALLS COOPERATING WITH BOTTOM AND BACK WALLS AND WITH FRONT WALL MEANS TO DEFINE A FLOW CHAMBER, SAID FRONT WALL MEANS INCLUDING A FRONT WALL MEMBER SECURED IN RIGID RELATION WITH SAID TOP WALL AND AN UPPER SLICE LIP OF RIGID CONSTRUCTION CARRIED BY SAID FRONT WALL MEMBER IN DEPENDING RELATION THEREWITH AND COOPERATING WITH SAID BOTTOM WALL TO DEFINE A SLICE OUTLET FROM SAID CHAMBER, SAID FRONT WALL MEANS ALSO INCLUDING A THIN SECTION EXTENDING HORIZONTALLY THEREACROSS AND OF SUBSTANTIALLY LESS THICKNESS THAN SAID SLICE LIP TO PROVIDE FOR FORWARD AND BACKWARD SWINGING MOVEMENT OF SAID SLICE LIP WHILE MAINTAINING SAID LIP IN SEALED RELATION WITH SAID FRONT WALL MEMBER, MEANS FORMING AN INLET FOR STOCK AT THE BACK OF SAID CHAMBER TO PROVIDE FOR GENERALLY HORIZONTAL FLOW OF THE STOCK TOWARD SAID SLICE LIP FOR DISCHARGE THROUGH SAID OUTLET, A PAIR OF RECTIFIER ROLLS LOCATED ADJACENT SAID OUTLET IN NON-UNIFORMLY SPACED RELATION THEREWITH AND IN CLOSELY SPACED RELATION WITH EACH OTHER AND WITH SAID BOTTOM WALL AND SLICE LIP RESPECTIVELY, SAID THIN WALL SECTION BEING LOCATED AT A HIGHER LEVEL THAN SAID RECTIFIER ROLLS, MEANS CONNECTED BETWEEN SAID SLICE LIP AND SAID SIDE WALLS FOR MOVING SAID SLICE LIP FORWARD AND BACKWARD ABOUT SAID THIN SECTION, AND MEANS MOUNTING SAID RECTIFIER ROLLS ON SAID SIDE WALLS FOR ADJUSTMENT SUBSTANTIALLY PARALLEL WITH SAID BOTTOM WALL TO MAINTAIN SAID SPACED RELATION THEREOF TO EACH OTHER AND TO SAID BOTTOM WALL AND SAID SLICE LIP IN ACCORDANCE WITH THE MOVED POSITION OF SAID SLICE LIP.

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