US3017929A

US3017929A - Head box with balanced slice body

Info

Publication number: US3017929A
Application number: US785439A
Authority: US
Inventors: Edward D Beachler
Original assignee: Beloit Iron Works Inc
Current assignee: Beloit Iron Works Inc
Priority date: 1959-01-07
Filing date: 1959-01-07
Publication date: 1962-01-23
Anticipated expiration: 1979-01-23

Description

Jan. 23, 1962 E. D. BEACHLER 3,017,929

HEAD BOX WITH BALANCED SLICE BODY Filed Jan. 7, 1959 [EVEN/UP 5 [1mm 0. 9540/15 2 Z /AZF M fl/W M @W @375 3,017 929 HEAD 30X WKTH BAL ANCED SLHCE BODY Edward D. Beachler, lteloit, Wis, assignor to Beloit Iron Works, Beioit, Wis., a corporation of Wisconsin Filed Jan. 7, 1950, Ser. No. 785,439 14 Claims. (Cl. 162340) created in the design of paper making machines of un-' usual width. The principles taught by the invention, however, have broad and unusual merit and are thus adaptable to paper making machines of any size. Paper making machines, particularly of the Fourdrinier type, customarily employ a head box in which a pond of stock is maintained and caused to flow by its own weight onto the making wire or other forming surface. This flow has been conventionally controlled by a slice which together with the floor member of the head box constitutes a rectangular opening which permits a jet of stock the width of the machine and uniform thickness to issue. As speeds and widths have increased the forces upon this slice member have continually increased making it necessary to stiffen the slice body in various ways. Also common in the paper making art is the use of the air pressure head box in which a cover is added to the box permitting the retention of a pressurized air pad above the free surface of the stock.

Since the jet mentioned preferably issues at a speed equal, or close to, the speed of the making wire, pressures for paper making machines to operate at 2000 f.p.m. or more have become so high that conventional means of stiffening the slice body have been unsatisfactory. The slice body has become higher and thicker until it is extremely diflicult today for the operator to observe the behavior of the issuing slice or to make the necessary minute local adjustments to insure the uniformity of depth of the jet itself.

The force tending to lift top wall of the conventional head box has little or no effect on the behavior of the remainder of the box in the conventional design. In this invention this lifting force due to the internal pressure is employed to counteract in part the weight of the slice body assembly and in part the horizontal force on the forward wall. By combining at least a part of the top wall with the slice body there is developed a stiffness to resist the horizontal effects of the internal pressure which is almost equivalent of the slice body of the thickness selected as the top part of the integral body. In the conventional design the thickness horizontally of the slice body could not practically be made sufiicient to resist the tendency to bend outwardly. The jet rather than being rectangular took the shape of the bent slice lip. By combining a part at least of the top wall member with the normally vertical slice member into an integral construction of L configuration the instant device provides a means of effectively balancing out and/or resisting the forces due to the internal pressure. Additionally this construction permits the placement of the outer wall or skin members in the position to resist the resulting stresses with utmost efficiency somewhat in the manner termed in the aircraft arts: monocoque.

As another feature of the instant invention, the horizontal thrusts due to internal pressure which operate upon the front wall portion of the slice body are resisted by 2.

States Patent plurality of tie bars. This feature has a number of advantages. The tie bars are enclosed within the body of the slice structure and thus are protected from the frequently corrosive influence of the stock. The tie bars are pivotally mounted, which permits the operation of a simple, direct and effective lifting and positioning of the slice lip itself without interference. They further prevent the entire reaction from being applied in the end walls of the head box.

The construction afforded by this invention makes possible the use of simple, direct, self-locking adjusting means operating vertically to provide for both the necessary vertical adjustment of the slice opening itself and the necessary and desirable longitudinal positioning of the slice lip.

It will thus be seen that the instant device provides a number of novel advantages in the operation of a head box of substantial size.

It is, therefore, an important object of the instant invention to provide an improved stock flow means for depositing stock onto a traveling forming wire.

It is also an object of the instant invention to provide a head box for paper making machinery having an interior unobstructed by stressed members, capable of resisting internal pressures and forces of great magnitude while avoiding undesirable deflections and permitting the most effective use of the materials of construction.

It is another object of the instant invention to provide, in a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for siock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stock fiow from within the stock flow means, and vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect'verticall movement of the top wall leading edge.

Still another object of the instant invention is to provide an improved paper machine having a looped forming wire and stock fiow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, said top wall having inner and outer skins in the general configuration of nested angle irons secured together at their edges and apexes, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of the outer skin resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, and vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge.

Other and further objects, features and advantages of the present invention will become apparent to those skilled in the art from the following detailed disclosure thereof and the drawings attached hereto and made a part hereof.

As shown in the drawing, the reference numeral 10 indicates generally an improved head box of the instant invention. In the view shown, the head box 10 is shown Patented Jan. 23, 1962 in side elevational view with parts shown in section and parts shown diagrammatically. The device 10 is here shown mounted on fixed supports 11 and 12 between which is a cross current stock feed device of conventional design. The view of the device it) is taken from the front side of the machine; and the cross current stock feed device indicated generally by the reference numeral 13 comprises a source of stock under pressure 8- which flows stock into two generally parallel upwardly inclined stock ducts f4 and 15, which extend substantially the full width of the machine. tock flows from the source S through an inlet line 16 to the back side of the machine and into the duct 14 and then upwardly through the duct 14 and past a rectifier roll 18. Additional stock flows from the source S through a line 17 and into the front side of the duct 15 and then upwardly past a rectifier roll 18, whereat the stock streams from the

ducts

14 and 15 merge and flow upwardly into an inlet 20 for the head box 10.

The head box 10 is provided with a bottom wall 21, with supports 21a and 21b. The bottom wall 21 is substantially aligned with the top run 22a of a forming wire 22 that is trained around a breast roll 23 in the usual manner. The bottom wall 21 has a leading edge 21c extending laterally the full width of the wire 22 and in close proximity tothe wire 22. The head box 10 also has

opposite side walls

24, 24, only the back wall 24 being shown herein. Completing the enclosure with the bottom wall 21 and the front and

back side walls

24, 24 is a rear head box wall 25, which is in the form of generally nested L-shaped inside 25a and outside 25b skins with rigid supports 25c extending therebetween and welded thereto. As here shown, the rear wall 25 has a turned top portion 25d which forms a portion of the top of the head box 10 and terminates with a face portion 252 extending between the inner and outer skins 25a, 25b.

The bottom wall 21, side walls 24, 2e and rear wall 25 are suitably secured together in a rigid sealed structure that is mounted on fixed supports 12 and 11. There is also provided a relatively movable top-front wall combination 26 which has a leading edge or slice lip 26a extending laterally of and in close proximity to the wire 22. The top-front wall leading edge 26:: is spaced from the bottom wall leading edge 21c to define a stock outlet or slice jet for stock to flow onto the wire 22. It is essential that the slice jet and, therefore, the slice lip 26a remain in a predetermined position under operating conditions. In other words, the s ice lip 26:: must remain in predetermined spacing from the wire 22 and the bottom wall leading edge 21c throughout its entire width, no matter what changes in pressure or the like operating conditions may take place within the head box 10. This particular spacing can and must, of course, be changed for certain differences in operating conditions, but such change must be made in a predetermined manner.

In other words. if an appreciable deflection occurs at the slice lip 26a due to the internal pressure which in turn is determined by the speed at which the machine will perate then a change in local adjustments must be made to compensate for such deflection at each and every change in speed. It will also be observed that the internal operating pressure tends to lift the horizontal part of the L-sectio-ned slice body so that this force is employed to partially or wholly overcome the effect of the weight of the slice body as well as the horizontal force on the forward wall. Since these two forces of considerable magnitude are in opposite directions the remaining force tending toward a vertical deflection is reduced to that due to the difference between the forces.

First of all it will be noted that the top wall 26 has a top portion 26b and a front portion 260; but the unitary top-front wall 26 is formed about a plurality of sheer members or plates 26m having the general L configuration. The top wall portion 26b has inner 26d and outer 26a skin or surface members which are joined at their terminal edges with face portion 26f. The vertical or front portion of 26c is likewise composed of surface or skin members 26p (inner) and 26! (outer) which in turn are joined at their terminal edges by a lower closure member 26g. The surface or skin members are thus placed in positions to bear most efficiently the stresses involved and in this manner bear resemblance to the type of construction known in the aircraft arts as a monocoque. The upper face member 26 is contiguous to the rear wall face portion 252 and relatively movable with respect thereto. A sealed member 27 provided with adjustable means (shown diagrammatically at 28) is interposed between the relatively movable contiguous face portions 25@ and 26) and forms a seal therebetween so as to complete the sealing of the head box 10. The seal member 27, as shown, has an inner tubular member in the form of a rigid rod and an outer covering formed by a sealing material such as rubber. As will be appreciated by those skilled in the art, various positioning devices may be employed such as arms actuated by air cylinders to positively engage the seal or by a resilient lifting force as applied by a spring means.

Before describing further details of the top wall 26, it will be noted that the interior of the head box 10 is provided with a suitable source of gas under pressure, such as an air inlet 29 for maintaining a predetermined pressure of gas at the level L for the stock; and the level L for the stock is maintained by a gas and liquid drain aperture 30 of conventional construction. If the level L rises above the drain 30, the pressure from air from the inlet 29 will increase and drive the level L downwardly. If the level L falls below the drain aperture 30, then a substantial amount of air pressure is released from the head box 10 and the level L will tend to rise. In this way a predetermined total head of liquid and gas under pressure is maintained on the stock in the head box 10 and thus at the slice between the leading edges 21c and 26a.

Also shown within the head box 10 are a manhole and observation window 31, stacked rectifier rolls 32 and 33 and bridging rectifier rolls 34 and 36 bridging the slice between the slice lip 26a and the bottom leading edge 210.

The top wall 26 is swingably mounted on pivots so as to permit upward swinging movement of the top wall 26 as well as horizontal movement back and forth at the slice lip 26a. First of all, a plurality of laterally spaced tie rods (only one of which is shown at 40) are secured by pivots 41 fixed to the stationary face portion 25e of the rear wall 25. The tie rods 40 extend forwardly to a movable pivot pin 42 that is secured to the front portion of the outer skin 26c, at 26k. The tie rods 40 serve to hold the entire front portion 26c of the top wall 26 in fixed position and resist horizontal bowing of the slice 26a. In addition, it wil be noted that the inner skin 26a is not in the shape of a perfect angle iron or L in crosssection, but is flattened at the apex by a wall portion 26l to which is connected the support member 26/1.

Additionally, it will be noted that additional stress distribution members 26h and 2611 permit the distribution of the reaction on the pin 42 throughout the main body of the combined top-front wall. In this way the L is strengthened to resist the tendency to separate or open to a greater included angle under the influence of the pressure forces within the head box chamber.

It will be appreciated that the top wall 26 is a structure of substantial size and strength and weight, so that it tends to resist, because of its weight alone, a substantial amount of the overall lifting force applied against the inner skin 26d thereof. The force resisting the tendency to lift the entire top wall 26, which here forms the slice body, is provided by vertically adjustable means indicated generally at 43. The vertically adjustable means 43 comprise a rod 43a connected to a pivot pin 44 at a forward top portion of the top wall 26. The rod 43a is mounted for vertical adjustment actuated by a worm box 43b, which is of conventional structure. As here shown, the worm box 43b comprises a worm 43c rotatably driven by clutch and drive means 45 and driving a worm gear (within the box 4312) which is in the form of a sleeve with its interior threadedly engaging a screw 43d, so that axial movement between the box 43b and the screw 43d results in vertical movement of the pivot pin 44. As will be seen the worm box 4311 is connected to a fixed pivot pin 46, which is connected to an extension 24a of the back side wall of the head box 10. Sealing strips (not shown) are provided for sealing engagement between the fixed

side walls

24, 24 and the relatively movable top wall 26 (and slice body). A cross bar 47 in front of the top wall 26 connects the

side Walls

24, 24 and affords additional support resisting separation of the side walls.

In operation it will be seen that the desired vertical adjustments to the slice lip 26a may be performed by actuating lift means 43 and 50 together as provided for by the clutch and drive mechanism 45. By the simultaneous actuation of these drive means it will be observed that the slice body combination 26 may be selectively raised or lowered in a substantially vertical direction. A minor but insignificant departure from the vertical occurs under the influence of the tie rods 40 mounted on

pivots

41 and 42.

As is well understood in the art the horizontal or longitudinal movement of the slice lip 26a with respect to the apron lip 21c is often desirable. This adjustment, when desired, is obtained very simply by the actuation of adjustment means 50 alone. The clutch and drive means will be understood to provide for a selective actuation of 43 and 50 together or 50 alone. Movement of pivot pin 51 which is secured to the rear face of the top front slice 267' and operatively connects lifting strut 50a tends to rotate the member 26 about an imaginary pivot line designated as P. This imaginary pivot axis P is a result of a combination of rotations occurring about the several pivot locations and will be well understood in the art.

The driving clutch mechanism 45 is mounted integrally upon the top-front member 26 and will move in synchronism with the lift mechanisms 43 and 50 as they lift or lower. The flexible shaft couplings of conventional design will provide for minor irregularities resulting from the slight pivotal movement.

It will be appreciated that, although shown herein only on the back side wall 24, adjustable means 43 and 50 are mounted also on the front side wall 24 (not shown) and driving thereof is coordinated with driving of said means 43 and 50 on the back side wall 24. Although other vertically adjustable means may be used in the instant device, it will be appreciated that the instant means are preferred. As here shown, the worm gear within the housing in each is mounted on bearings therein and moves with the housing and the depending rods 43a and 50a also move with the housing and are connected to pivot

pins

44 and 51, respectively. In addition, the clutch and drive means 45 are adjusted so as to simultaneously or selectively actuate the devices 43 and 50. If the device 50 is actuated alone the slice lip 26a tends to move generally horizontally, either forward or backward depending upon the vertical movement resulting in the pivot pin 51. Actually, the two pivot point P of the balanced slice body or top wall 26 is adjacent the pivot pins 42 and 44, as indicated. Vertical movement of the pivot pin 51 effects tilting about the pivot point P. Simultaneous vertical movement of the pivot pins 44 and 51 results in a movement of the slice lip 26a upwardly and rearwardly (or downwardly and forwardly, as the case may be).

It will be understood that modifications and variations may be effected without departing from the spirit and scope of the novel concepts of the present invention.

I claim as my invention:

1. In a paper machine having a looped forming wire,

stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stockflow from within the stock flow means, and vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to elfect vertical movement of the top wall leading edge.

2. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top Wall resisting pressures exerted by stock against the top wall in the direction of stock fiow from within the stock flow means, and vertically adjustable means connected to a fixed pivot and also pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top Wall leading edge.

3. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the Wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, first vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge, and second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said tie bars and said first adjustable means to effect horizontal movement of the top wall leading edge.

4. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, first vertically adjustable means pivotally connected to the forward portion of said top wall to effect vertical movement of the top wall leading edge, and second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said first adjustable means to effect horizontal movement of the top wall leading edge.

5. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, a pinrality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, first vertically adjustable means connected to a first fixed pivot and also pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge, and secnd vertically adjustable means connected to a second fixed pivot and also pivotally connected to rear portion of said top wall cooperating with said tie bars and said first adjustable means to effect horizontal movement of the top wall leading edge.

6. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, said rear wall and said top wall having relatively movable contiguous face portions, seal means positioned between said face portions, means for adjusting the position of said seal means relative to said face portions to insure maintenance of a non-leaking seal, and vertically adjustable means pivotally connected to the forward portion of said top wall to effect vertical movement of the top wall leading edge.

7. In a paper machine having a looped forming wire, stock fiow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom Wall leading edge to define a stock outlet from said stock flow means onto said wire, said rear wall and said top wall having relatively movable contiguous face portions, adjustable seal means positioned between said face portions, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, and vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge.

8. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, said rear wall and said top wall having relatively movable contiguous face portions, adjustable seal means positioned between said face portions, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, first vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge, and second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said tie bars and said first adjustable means to effect horizontal movement of the top wall leading edge.

9. In a paper machine having a looped forming wire,

stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock out let from said stock flow means onto said wire, said top wall having inner and outer skins in the general configuration of nested angle irons secured together at their edges and apexes, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of the outer skin resisting pressures exerted by stock against the top wall in the direction of stock fiow from within the stock flow means, and vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge.

10. In a paper machine having a looped forming wire, stock flow means comprising a bottom Wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leadingedge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, said top wall having inner and outer skins in the general configuration of nested angle irons secured together at their edges and apexes, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of the outer skin resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock fiow means, first vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to efiect vertical movement of the top wall leading edge, and second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said tie bars and said first adjustable means to effect horizontal movement of the top wall leading edge.

11. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, said rear wall and said top wall having relatively movable contiguous face portions, adjustable seal means positioned between said face portions, said top wall having inner and outer skins in the general configuration of nested angle irons secured together at their edges and apexes, a plurality of tie bars pivotally connected to said rear wall and to a forward portion of the outer skin resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, first vertically adjustable means pivotally connected to the forward portion of said top wall cooperating with said tie bars to effect vertical movement of the top wall leading edge, and second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said tie bars and said first adjustable means to effect horizontal movement of the top wall leading edge.

12. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire and a plurality of tie bars pivotally connected to said rear wall and to a forward portion of said top wall resisting pressures exerted by stock against the top wall in the direction of stock flow from within the stock flow means, said tie bars permitting swinging movement of said top wall relative to the rear wall.

13. In a paper machine having a looped forming wire, stock flow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock fiow means onto said wire, first vertically adjustable means pivotally connected to the forward portion of said top wall to effect vertical movement of the top wall leading edge, second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said first adjustable means to efiect horizontal movement of the top wall leading edge, a first drive member for operating said first vertically adjustable means, a second drive member for operating said second vertically adjustable means, and means for selectively in dependently or jointly operating said first or said second drive members so that said movement of the top wall leading edge may be controlled.

14. In a paper machine having a looped forming wire, stock fiow means comprising a bottom wall having a leading edge extending laterally of and in close proximity to the wire, a rear wall defining with the bottom wall an inlet for stock into said flow means, a top wall having a leading edge extending laterally of and in close proximity to the wire, said top wall leading edge being spaced from said bottom wall leading edge to define a stock outlet from said stock flow means onto said wire, first vertically adjustable means pivotally connected to the forward portion of said top wall to effect vertical movement of the top wall leading edge, second vertically adjustable means pivotally connected to rear portion of said top wall cooperating with said first adjustable means to effect horizontal movement of the top wall leading edge, a first drive member for operating said first vertically adjustable means, a second drive member for operating said second vertically adjustable means, and a driving clutch mechanism connected to said first and second drive members and selectively engageable for operating either of said drive members alone or together so that said movement of the top wall leading edge may be controlled.

References Cited in the file of this patent UNITED STATES PATENTS 2,202,890 Berry June 4, 1940 2,736,246 Crittenden et al Feb. 28, 1956 2,749,815 Stewart June 12, 1956 FOREIGN PATENTS 697,321 Great Britain Sept. 23, 1953 OTHER REFERENCES Staege: Paper Trade Journal, vol. 122, N0. 14, Apr. 4, 1946, pages 151-152.