Papermaking machine headbox having vertically aligned vanes therein

Claim 2

In a headbox for a papermaking machine having a vertical front wall assembly, a vertical rear wall assembly, a structure defining a stock inlet chamber communicating through the rear wall assembly, structure defining a stock outlet chamber communicating through the front wall assembly, means defining a central flow passage between the horizontal structures from the rear wall assembly to the front wall assembly, and a plurality of parallel and vertical guide vanes in the flow passage and means defining channels therebetween extending from the inlet chamber to the outlet chamber, each said vanes being generally rectangular and having a pair of vertical edge portions and a pair of horizontal edge portions, the improvement comprising: a. each vane having a first key projecting horizontally outward and away from one of the vertical edge portions of each vane; b. each vane having a second key projecting horizontally outward and away from the other of vertical edge portions of each vane; c. a first horizontal shelf projecting from one of the vertical wall assemblies toward the central flow passage and defining a first keyway between the first shelf and one of the horizontal structures; d. a second horizontal shelf projecting from the other of the vertical wall assemblies toward the first shelf and defining a second keyway between the second shelf and one of the horizontal structures; and e. the first key projecting into the first keyway and the second key projecting into the second keyway to support each vane of the plurality of vanes between the front and rear wall assemblies to thereby provide support for the horizontal flow passage defining vanes between the front anD rear vertical wall assemblies.

Claim 3

In a headbox according to claim 1, wherein said means defining channels between said guide vanes includes spacers between adjacent vanes of said plurality of vanes with each spacer having a first key projecting into the first keyway between a pair of vane first keys, each spacer having a second key projecting into the second keyway between a pair of vane second keys, and each spacer having a midportion between its first and second key with said spacer midportion projecting vertically a predetermined distance into the flow passage and providing a horizontal surface cooperating with adjacent vanes to define the channel between the vanes.

Claim 4

In a headbox according to claim 2, horizontal structure above and below the vanes and spacers defining a chamber for containing pressurized fluid for loading the spacers against bowing away from the flow passage due to pressure of pulp stock within the flow passage.

Claim 5

In a headbox for a papermaking machine having a vertical front wall assembly, a vertical rear wall assembly, a structure defining a stock inlet chamber communicating through the rear wall assembly, structure defining a stock outlet chamber communicating through the front wall assembly, means defining a central flow passage between the horizontal structures from the rear wall assembly to the front wall assembly, and a plurality of parallel and vertical guide vanes in the flow passage and means defining channels therebetween extending from the inlet chamber to the outlet chamber, each said vanes being generally rectangular and having a pair of vertical edge portions and a pair of horizontal edge portions, the improvement comprising: a. each vane having a first pair of vertically spaced keys each projecting horizontally outward and away from one of the horizontal edge portions and one of the vertical edge portions of each vane; b. each vane having a second pair of vertically spaced keys each projecting horizontally outward and away from one of the horizontal edge portions and the other of the vertical edge portions of each vane; c. a first pair of vertically spaced horizontal shelves projecting from one of the vertical wall assemblies toward the central flow passage and defining a first pair of keyways between each of the first pair of shelves and an adjacent one of the horizontal structures; d. a second pair of vertically spaced horizontal shelves projecting from the other of the vertical wall assemblies toward the first pair of shelves and defining a second pair of keyways between each of the second shelves and an adjacent one of the horizontal structures; and e. each of the first pair of keys projecting into one of the first keyways and each of the second pair of keys projecting into one of the second keyways to support each vane of the plurality of vanes between the front and rear wall assemblies to thereby provide support for the horizontal vanes between the front and rear wall assemblies.

Claim 6

In a headbox for a papermaking machine having a vertical front wall assembly, a vertical rear wall assembly, a structure defining a stock inlet chamber communicating through the rear wall assembly, structure defining a stock outlet chamber communicating through the front wall assembly, means defining a central flow passage between the horizontal structures from the rear wall assembly to the front wall assembly, and a plurality of parallel and vertical guide vanes in the flow passage and means defining channels therebetween extending from the inlet chamber to the outlet chamber, each said vanes being generally rectangular and having a pair of vertical edge portions and a pair of horizontal edge portions, the improvement comprising: a. each vane having a first pair of vertically spaced keys each projecting horizontally outward and away from one of the horizontal edge portions and one of the vertical edge portions of each vane; b. each vane having a second pair of vertically spaced keys each projecting horizontally outward and away from one of the horizontal edge portions and the other of the vertical edge portions of each vane; c. a first pair of vertically spaced horizontal shelves projecting from one of the vertical wall assemblies toward the central flow passage and defining a first pair of keyways between each of the first pair of shelves and an adjacent one of the horizontal structures; d. a second pair of vertically spaced horizontal shelves projecting from the other of the vertical wall assemblies toward the first pair of shelves and defining a second pair of keyways between each of the second shelves and an adjacent one of the horizontal structures; and e. each of the first pair of keys projecting into one of the first keyways and each of the second pair of keys projecting into one of the second keyways to support each vane of the plurality of vanes between the front and rear wall assemblies to thereby provide support for the horizontal vanes between the front and rear wall assemblies.

Claim 7

In a headbox according to claim 4, wherein said means defining channels between said guide vanes includes spacers between adjacent vanes of said plurality of vanes along both horizontal edge portions thereof with each spacer having a first key projecting into one of the first keyways between a pair of vane first keys, each spacer having a second key projecting into one of the second keyways between a pair of vane second keys, and each spacer having a midportion between its first and second key with said spacer midportion projecting vertically a predetermined distance into the flow passage and providing a pair of facing horizontal surfaces between adjacent vanes, with the facing horizontal surfaces providing a channel floor and channel ceiling cooperating with adjacent vanes to define a channel therebetween of rectangular cross section extending horizontally the length of the vanes and spacers.

Claim 8

In a headbox according to claim 5, horizontal structures defining the box floor and top each further defining a chamber belOw and above, respectively, the flow passage for containing pressurized fluid for loading the spacers against bowing downwardly and upwardly away from the flow passage due to pressure of pulp stock within the flow passage.

Claim 9

In a headbox according to claim 4, the front wall assembly comprising a first member and a second member on the stock outlet side of the first member with the second front wall member being movable vertically relative to the first front wall member, one shelf of the first pair of shelves being connected to the second front wall member and movable therewith, a screw operatively connected to the first and second front wall members for moving the second front wall member and the shelf connected thereto vertically away from the vanes to eliminate clearance between the shelf and the upper key of the first pair of vertically spaced keys so that when the headbox is pressurized vertical tension is applied to the vanes between the first pair of vertically spaced vane keys.

Claim 10

In a headbox according to claim 4, the rear wall assembly comprising a first member and a second member on the stock inlet side of the first member with the second rear wall member being movable vertically relative to the first rear wall member, one shelf of the second pair of shelves being connected to the second rear wall member and movable therewith, a screw operatively connected to the first and second rear wall members for moving the second rear wall member and the shelf connected thereto vertically away from the vanes to eliminate clearance between the shelf and the upper key of the second pair of vertically spaced keys so that when the headbox is pressurized vertical tension is applied to the vanes between the second pair of vertically spaced vane keys.