US2688277A

US2688277A - Paper machine head box

Info

Publication number: US2688277A
Application number: US225959A
Authority: US
Inventors: Jerome J Luebke
Original assignee: Marathon Corp
Current assignee: Marathon Corp
Priority date: 1951-05-12
Filing date: 1951-05-12
Publication date: 1954-09-07
Anticipated expiration: 1971-09-07

Description

Sept. 7, 1954 J. J. LUEBKE PAPER MACHINE HEAD BOX 3 Sheets-Sheet 1 Filed May 12, 1951 MfVE/VTQR JEROMEJ Ma E 6 MQ p 7, 1954 J. J. LUEBKE 88,277

PAPER MACHINE HEAD BOX Filed May 12, 195] 3 Sheets-Sheet 2 Firm 2 )NVENTOR JEROME} Z UEBIKE Sept. 7, 1954 J. J. LUEBKE PAPER MACHINE HEAD BOX 5 Sheets-Sheet 3 Filed May 12, 1951 IN l EN TOR JEROME jig/$5M BY Q /4 TORNE Y Patented Sept. 7, 1954 PAPER MACHINE HEAD BOX Jerome J. Luebke, West De Pere, Wis., assignor,

by mesne assignments, to Marathon Corporation, Mcnasha, Wis., a corporation of Wisconsin Application May 12, 1951, Serial No. 225,959

13 Claims.

The present invention relates to paper making machines of the Fourdrinier type, and more particularly to head boxes or flow boxes for such machines.

An object of the invention is to provide an improved. head box of simple, durable and inexpensive construction in which the pulp or stock will be uniformly distributed or spread over the width of the head box and caused to flow from the head'box in a smooth flat stream onto the paper-forming surface of the Fourdrinier wire belt.

Another object is to provide a flow-distributing head box in which the incoming stock flows transversely thereof, and which is so arranged as to conserve floor space.

A further object is to provide simple but effective means for adjusting or equalizing the distribution of the stock over the width of the head box.

The invention further consists in the several features hereinafter described and claimed.

In the accompanying drawings,

Fig. 1 is a longitudinal sectional elevational view of a head box constructed in accordance with the invention;

Fig. 2 is a top view of the stock-distributing portion of the head box, parts being broken away and parts being shown in section;

Fig. 3 is a sectional elevational view taken generally on the line 33 of Fig. 2;

Fig. 4 is a sectional elevational view taken generally on the line l4 of Fig. 2, and

Fig. 5 is a fragmentary sectional detail View taken generally on the line 5-5 of Fig. 3.

In these drawings, H] designates generally a head box or flow box of the invention, and II designates a breast roll over which is trained a conventional Fourdrinier wire belt l2 presenting a paper-forming surface. The head box is provided at its front end with a discharge nozzle or channel E3 of rectangular slot-like cross-section extending over the width of the head box and terminating at an orifice-forming slice Hi from which the pulp or stock spouts under the pressure of a gravity head in a smooth flat stream or sheet onto the traveling wire belt. The discharge nozzle, which is of metal construction, is here shown to be forwardly and downwardly inclined and has a portion with sloping parallel top and bottom walls between which is placed a flow evener 45 of grid-like or honeycomb crosssection. The slice includes upper and lower walls or lips which converge forwardly to form the discharge orifice, the swingably mounted upper lip being operatively connected to a suitable adjusting mechanism l6 for varying the width of the orifice. The downstream end of the lower slice lip is horizontal and close to the upper run of the wire belt, this slice lip end being disposed a short distance rearwardly of the vertical center line of the breast roll. The head box and slice are mounted on a suitable framework IT.

The head box, which is of generally rectangular shape and may be largely of reinforced wood construction, includes parallel vertical side walls It and IS, an upper vertical front wall 20, a lower vertical front wall 2| offset rearwardly from the upper front wall, an upper vertical rear wall 22, a lower vertical rear wall 23 offset forwardly from the upper rear wall, a horizontal bottom wall 24 which extends to the side walls and to the lower front and rear walls, and a horizontal shelf 01' platform 25 which extends from the lower edge of the upper rear wall to the upper edge of the lower rear wall. The inclined discharge nozzle or channel 13 extends from the space between the upper and lower front walls.

The head box has formed therein various passages and chambers hereinafter described to distribute or spread the incoming stock, to reduce turbulence, and to provide for a smooth gravity flow of well-mixed stock into the discharge nozzle 13.

An inlet or distributing chamber 26 of elongated rectangular shape is formed between the upper rear head box wall 22 and the upper portion of a transversely extending vertical baffle wall or dam 21, the shelf or platform 25 forming the bottom of this chamber. The baiile wall 21 is spaced forwardly from the lower rear wall 23 and forms therewith a vertical down-pass 28 extending over the width of the head box and communicating at its upper end with the elongated distributing chamber, which also extends over the width of the head box. The bafiie Wall 27 is here shown to be of double construction and to have its ends mortised into the side walls of the head box. The baffle wall 21 and upper end wall 22 are connected at their upper edges by cross bars 29. The horizontally extending distributing chamber has a lateral extension 3|], Figs. 2 and 4, formed between a projecting portion of the upper rear wall 22 and a parallel vertical Wall 3| spaced forwardly from the upper rear wall and disposed in the plane of the lower rear wall 23. The wall 3| is connected to the side wall IQ of the head box at a junction presenting a rounded inner surface 32, and the outer end of the extension is closed by a vertical wall 33 which is parallel to the side wall. A curved metal elbow 34, supported on standards 35 and 3 36, has a rearwardly projecting horizontal intake 3'! with a flanged end connected to a horizontal stock pipe 38, Fig. 1, and has an upwardly projecting delivery end portion 39 secured in the bottom of the lateral extension 30 of the distributing chamber 25, the elbow being of rectangular cross-section except for the intake portion 37 thereof which converges to a circular end to match the stock pipe 33. The upper portion of the elbow 34 has parallel, vertical front and

rear walls

40 and 4!, Fig. 1, and upwardly diverging

side walls

42 and 43, Fig. .4, the latter wall having at its upper end a horizontal lip 44 resting on the end of the platform 25. The vertical wall 40 is aligned with the inner vertical surface of the laterally extended upper rear wall 22 of the head box. Arcuate turning vanes 45 are mounted in the curved portion of the elbow, and are spaced from each other and from the cylindrically curved walls of the elbow to form flow passages of approximately equal cross-sectional area.

Mounted in the elongated, elevated distributing chamber 26 are a series of spaced

curved vanes

46, 41, 48, 49, 50, and best seen in Fig. 2, for distributing and directing the incoming pulp or stock over the width of the head box and equalizing the flow into the down-pass 28 extending from the distributing chamber, each vane being curved through substantially 90 in a horizontal directions. The vanes are formed of resilient metal, such as copper, and have vertical walls which are nearly as high as the chamber 26 and which rest at their lower edges on the platform 25. Each curved, vertical vane has upstream and downstream ends disposed substantially at right angles to each other. At the end remote from the elbow 34 the distributing chamber has a curved turning wall 52, Fig. 2, which cooperates with the endmost vane 5 l. The downstream ends of the vanes, which project forwardly over the down-pass 28, extend generally parallel to the side walls of the head box and are approximately equally spaced, each vane end being secured to a Vertical angle bar 53 which is fastened, as by screws 54, to the rear face of the vertical bafiie wall or darn 21. At its downstream end each vane has a vertical extension 55 which projects downwardly into the upper portion of the down-pass 23 and fits therein. The curved vanes in the distributing chamber have parallel upstream ends which extend toward the lateral intake of the chamber in generally parallel relation to the bafile wall 2'! and upper rear head box wall 22. The upstream ends of the several vanes are preferably arranged in echelon relation, as seen in Fig. 2, the vane 46 being nearest the chamber extension 30. Curved, elbow-shaped flow passages 56 are formed between adjacent vanes and between the endmost vanes and the walls of the distributing chamber, the vertically elongated entrance portions of these passages being of approximately equal width, and each passage widening considerably in a downstream direction. The width of the downstream or discharge end of each curved flow passage 56 is several times as great as the Width of the upstream or entrance end. The upstream end of each vane is confined in laterally adjusted position by horizontal rods 51, such as of brass or other corrosion-resistant metal, which pass through openings 58 in the vane, and carry washers 59 which engage opposite sides of the vane and are suitably retained in position, as

by cotter pins 60, Fig, 5. The rear end portion of each rod passes through the upper rear wall 22 of the head box and is screw-threaded through a bracket Bl secured to this wall, and the rear extremity of the rod has a head 62 for adjusting the rod. The front ends of the rods are slidably guided in bores 63 formed in the bafile wall 21, except for the rods for the vane 46 the front ends of which are guided in similar bores 63 formed in the extension wall 3|, Fig. 2. The adjusting rods for each vane (except the rods for the vane 46) loosely pass through openings 64 formed in the adjacent vane. The vane 5| is here shown to be additionally supported from the upper rear end wall 22 by one or more rodlike spacers 65, Fig. 2, at some distance downstream from the associated adjusting rods 51. Lateral displacement of the upstream end of each resilient vane by the associated adjusting rod will vary the entrance width of the associated flow passage at the forward side of the vane end and thus adjustthe extent of stock flow into the passage.

The lower rear head box wall 23 has a rounded junction with the bottom wall 24, and the vertical baffle wall 21 has a rounded lower edge spaced from the bottom wall to form a slot-like passage 86 providing communication between the lower end of the down-pass 28 and a stilling chamber 61, the latter chamber having a volume several times as large as the volume of the downpass. The front of the stilling chamber 6! is formed by a steeply sloping baffle wall 68 extending upwardly and rearwardly from thebottom wall 24, the lower end of this bafile wall having a rounded junction with the bottom wall, and the upper edge of this bafile wall being higher than the bottom wall 25 of the distributing chamber. The stilling chamber has a normally closed drain opening 69 formed in the side wall l8. An inclined table 10 slopes forwardly and downwardly at an angle of about 20 from the rounded upper edge of the baffle wall 68 to the rounded upper edge or a vertical baffle wall 1! extending to the bottom wall 24, the upper end of the baffle wall ll being higher than the entrance of the discharge nozzle l3, and the lower end of the baflle wall H having a rounded flow surface 12. The bafile walls 68 and H and table l9 form a dam the broad upper end of which is normally submerged.

A transversely extending vertical bafile wall or dam 13 is disposed between the baffle wall H and the lower front wall 2| in spaced relation to these walls, and has a rounded lower edge spaced above the bottom wall to form a slotlike passage 74. The baflle walls H and 13 form a down-pass 15 between them, and the baflle wall 13 and the lower front wall 21 form an up-pass it between them, the passage 74 providing communication between the down-pass and the uppass and being considerably narrower than the width of each of these passes. The lower end of the up-pass '16 has a normally closed drain opening 1'! formed in the side wall E8 of the head box.

The baiile wall or dam 13, which is similar to the baffle wall or dam 2'! and is mortised in the head box side walls, has an upper edge near the top of the head box, and is vertically adjustable to vary the width of the passage 14. Above the inclined table 10 the stilling chamber widens to extend between the parallel bafile walls 21 and 13. The inclined table serves to prevent or minimize cascading into the down-pass 75, particularly at starting and during low feeds, and

acsaaw also serves to facilitate release of air bubbles from the stock.

Between the baiiie wall 13 and the upper front wall 20 is formed a chamber 18 to which stock is delivered from the up-pass l6. A suitable head of stock is maintained in this chamber from Which stock flows by gravity into the discharge nozzle is. The height of the stock in the chamber 18 determines the spouting velocity of the stock at the slice M, this velocity corresponding to the linear speed of the Fourdrinier wire belt. The stock level in the chamber 18 is adjusted by varyingthe rate of stock inflow to the distributing chamber. The narrow passage 14 between the lower ends of the down-pass 15 and the up-pass 16 increases the stock velocity at this region, so as to effect mixing of the stock shortly before it is discharged from the head box. If it is observed that the velocity is too great, resulting in excessive disturbance of the stock when it enters the discharge nozzle [3, the baffle wall or dam I3 is raised a sufiicient amount to reduce or eliminate the disturbance.

In the operation of the paper machine, pulp or stock is pumped at a selected rate of flow through the stock pipe 38 and passes upwardly in the elbow 3 into the lateral extension 30 of the distributing chamber 26, the stock flow being distributed over the cross-section of the rectangular delivery end 39 of the elbow by the turning vanes 45. The velocity of the stock decreases as the stock passes through the elbow. From the chamber extension 39 the Stock first flows horizontally along the elongated distributing chamber crosswise of the head box and is then turned or directed forwardly of the head box by the curved passage-forming vanes 46 to 5!, so that the stock flow in the down-pass 28 of the head box is divided or distributed across the width of the head box. The optimum distribution can readily be provided by laterally shifting the upstream ends of the vanes 46 to 5! by the adjusting rods 51. These vanes serve not only to distribute and direct the flow but also to reduce turbulence of the stock before it enters the down-pass 28. The downstream vane projections 55 act to straighten the flow in the down-pass. The flow in the down-pass is produced by the head of stock in the distributing chamber rather than by direct pumping pressure, and is unaffected by pump pulsations. From the lower end of the down-pass the stock flows through the curved passage 66 into the bottom of the stilling chamber 61, and thence upwardly and over the inclined dam-forming table 10 through the down-pass 15, the bottom passage 14, the up-pass Iii, and into the discharge chamber lil. Mixing of the stock is effected as the stock flows at increased velocity through the narrow passage 14. The stock then flows into the discharge nozzle [3 under the head of stock in the chamber 13, passes through the flow evener l5 and the slice l4, and spouts from the slice orifice to lay a smooth flat stream of stock of glassy appearance onto the traveling wire belt. The stock entering the discharge nozzle is free from major disturbances, and any remaining minor disturbances are removed in the flow evener 15, the extended wall surfaces of which exert a mild mixing action on the stock. The smooth flat stream of well-mixed stock laid on the wire belt results in the formation of a paper sheet which is of uniform thickness and good quality.

The stock distributing means at the inlet or entrance portion of the head box is of such character that it will permit inexpensive construction and conserve floor space, while affording an even distribution or spreading of the stock over the width of the head box.

What Iclaim is:

1. In a paper making machine, a head box having at its rear portion a stock distributing chamber extending transversely of the head box and provided with a stock intake at an end portion of said chamber adjacent to a side of the head box, said chamber having an outlet extending along the front thereof and substantially across the width of the head box, and vertical flow-directing wall members in said chamber curved through substantially and forming flow-dividing passages between said intake and said outlet, said curved wall members having upstream ends projecting toward said intake in a direction transversely of the head box and having downstream ends projecting forwardly in the head box and spaced across the width of the head box to distribute the flow of stock through said outlet. v

2. In a paper making machine, a head box having a stock distributing chamber extending transversely thereof and provided with a stock intake at an end portion of said chamber, a down-pass in said head box extending substantially across the width of said head box, said down-pass having an entrance at its upper end communicating with the bottom of said chamber along the front of said chamber, and vertical flow-directing wall members in said chamber forming flow-dividing passages between said intake and said down-pass, said wall members being curved through substantially 90 and having upstream ends projecting toward said intake transversely of the head box and having downstream ends projecting forwardly in the head box and spaced across the width of the head box to distribute the flow of stock into said downpass.

3. In a paper making machine, a head box having a stock distributing chamber extending transversely thereof and provided with a stock intake at an end portion of said chamber, a down-pass in said head box extending substantially across the width of said head box, said down-pass having an entrance at its upper end communicating with the bottom of saidchamber along the front of said chamber, and vertical flow-directing wall members in said chamber curved through substantially 90 and forming flow-dividing passages between said intake and said down-pass, said curved wall members having upstream ends projecting toward said intake and having downstream ends projecting forwardly in the head box and spaced across the Width of the head box to distribute the flow of stock into said down-pass, the downstream ends of said wall members extending over the entrance of said down-pass.

4. In a paper making machine, a head box having a stock distributing chamber extending transversely thereof and provided with a stock intake at an end portion of said chamber, a down-pass in said head box extending substantially across the width of said head box, said down-pass having an entrance at its upper end communicating with the bottom of said chamber along the front of said chamber, and vertical flow-directing wall members in said chamber curved through substantially 90 and forming flow-dividing passages between said intake and said down-pass, said wall members having upstream ends projecting toward said intake transversely of the head box and having downstream ends projecting forwardly in the head box and spaced across the width of the head box to distribute the fiow of stock into said down-pass, the downstream ends of said wall members extending over the entrance of said down-pass and having portions projecting downwardly into said down-pass,

5. In a paper making machine, a head box having a stock distributing chamber extending transversely thereof and provided with a stock intake at an end portion of said chamber, said chamber having an outlet extending along the front thereof and substantially across the width of the head box, and vertical turning vanes in said chamber forming flow-dividing passages between said intake and said outlet, said vanes being curved through substantially 90 and having upstream ends projecting toward said intake and having downstream ends projecting forwardly in the head box and spaced across the width of the head box to distribute the flow of stock through said outlet, the upstream portions of said vanes being spaced to form entrances for said passages, and the upstream ends of at least some of said vanes being laterally displaceable to vary the width of said entrances for adjustably dividing the stock flow through said passages, and means for retaining said upstream vane ends in laterally adjusted position.

6. In a paper making machine, a head box having a stock distributing chamber extending transversely thereof and provided with a stock intake at an end portion of said chamber and with a bottom wall, said chamber having an outlet extending along the front thereof and substantially across the width of the head box, and vertical turning vanes in said chamber upstanding from said bottom wall, said vanes being curved through substantially 90 and extending between said intake and said outlet and forming flow-dividing passages, said vanes having downstream ends projecting forwardly in the head box and spaced across the width of the head box to distribute the flow of stock through said outlet, the upstream ends of said vanes being disposed in echelon relation.

'7. In a paper making machine, a head box having a flow spreading inlet chamber with a stock intake and with an outlet in the head box extending substantially across the width of the head box, flow-directing wall members in said chamber forming flow-dividing passages between said intake and outlet, said wall members being curved through substantially 90, the downstream ends of said wall members being spaced across the width of the head box adjacent to said outlet, said passages having upstream entrances, and the upstream ends of at least some of said wall members being laterally displaceable to vary the width of said entrances for adjustably dividing the stock flow through said passages, and means for retaining said displaceable wall member ends in laterally adjusted position.

8. In a paper making machine, a head box having a rear portion with a horizontally disposed stock distributing chamber extending transversely of the head box and provided with a bottom wall and with a stock intake at an end portion of said chamber, the horizontal dimension of said chamber in a direction lengthwise of the head box being substantially smaller than the width of said head box, said chamber having an outlet along its front portion extending substantially across the width of the head box and communicating with a second chamber of the head box, and vertical flow-directing wall members in said distributing chamber upstanding from said bottom wall and forming elbow-shaped flow-dividing passages, said wall members being curved through substantially and having downstream end portions extending forwardly in the head box and spaced across the width of the head box to distribute the flow of stock through said outlet and said wall members having upstream ends substantially at right angles to the down-stream ends and projecting toward said stock intake.

9. In a paper making machine, a head box having a front portion with a stock discharge opening and having a rear portion with a transversely extending stock distributing chamber, said chamber having a bottom wall higher than said discharge opening and further having a stock intake at an end portion of said chamber, a down-pass extending substantially across the Width of the head box and having a slot-like entrance at its upper end extending along the front of said bottom wall and communicating with said chamber, and flow-directing wall members in said chamber upstanding from said bottom wall, said wall members being curved through substantially 90 and forming flow-dividing passages which extend between said intake and said down-pass'and widen in downstream direction, said wall members having upstream ends projecting transversely of the head box toward said intake and having downstream ends projecting forwardly in the head box and spaced across the width of the head box to distribute the flow of stock into said down-pass.

10. In a paper making machine, a head box having a stock distributing section with a stock intake and a stock outlet, and vertical flowdirecting wall members in said section curved through substantially 90 and forming flow spreading passages between the intake and the outlet, said passages having upstream entrances, the upstream ends of at least some of said wall members being laterally displaceable to vary the entrance width of the associated passages for adjustably dividing the stock flow through said passages, and deflecting and retaining means for the displaceable upstream ends of said wall members having actuating portions at the exterior of said head box.

11. In a paper making machine, a head box having a stock distributing section with a stock intake and a stock outlet, and vertical flowdirecting wall members in said section forming flow spreading passages between the intake and the outlet, said wall members being curved through substantially 90, the upstream portions of said wall members forming entrances for the passages, the upstream ends of at least some of said wall members being laterally displaceable to vary the entrance width of the associated passages for adjustably dividing the stock flow through said passages, and axially shiftable retaining rods extending transversely of and operatively connected to the displaceable upstream ends of said wall members for holding said lastnamed ends in laterally adjusted position.

12. In a paper making machine, a head box having a front portion with a stock discharge opening and having a rear portion with a transversely extending stock distributing chamber, said head box having substantially parallel side walls one of which forms an end of said chamber, the other end of said chamber extending beyond the other of said side walls and having a bottom stock intake, said chamber having a bottom wall higher than said stock discharge opening, a down-pass in said head box extending substantially across the width of said head box and having a slot-like entrance at its upper end extending along said chamber bottom wall and communicating with said chamber, and flowdirecting means in said chamber forming with said bottom wall a plurality of flow-dividing passages extending between said intake and the entrance of said down-pass for distributing the flow of stock into said down-pass, said flowdirecting means including vertical vanes curved through substantially 90.

13. In a paper making machine, a head box having a horizontally disposed stock distributing chamber extending transversely thereof and provided with a bottom wall, said chamber having an end portion projecting laterally from a side of the head box and provided with a stock intake from which stock flows horizontally along said chamber crosswise of the head box, said chamber further having an outlet in said head box extending substantially across the width of the head box, and vertical flow-turning vanes in said chamber curved through substantially 90 and forming flow-dividing passages extending horizontally between said intake and outlet for distributing the flow of stock through said outlet, said curved flow-dividing passages increasing in width in downstream direction.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 847,857 Walker et a1. Mar. 19, 190"! 1,771,600 Yoder July 29, 1930 2,205,693 Milne June 25, 1940 2,225,435 Kellett et a1. Dec. 17, 1940 2,281,293 Lang Apr. 28, 1942 FOREIGN PATENTS Number Country Date 469,203 Great Britain July 21, 1937 512,808 Great Britain Sept. 26, 1939