USRE1381E - Improvement in the process of grinding paper-pulp - Google Patents

Description

v To all whom itmay concern:

- UNITED STATES PATENT 'OFFICEO 'JOSEPH KINGSLAND, JR, or FRANKLIN, NEW JERSEY.

IMPROVEMENT-IN THE PROCESS OF GRINDING PAPER-PULP.

Specification forming part of Letters Patent No. 13, 316, dated December 23, 1856; Reissue No. 744, dated June 28, 1859; Reissue No. 1,381, dated January 6, 1863.-

Be it known that I, JOSEPH Jr., of Franklin, in the county of Essex and State of New Jersey, have invented a new and useful Process for Reducing Fibrous Vegetable Matter to Pulp for the Manufacture of Paper, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which make part of this-specification, in which Figure 1 represents a vertical section of an engine suitable for carrying into effect my improved process. Fig. 2 represents an elevation of one end, and Fig. 3 an elevation of the other end of the same. i

The stock from which paper is made usually consists of rags, although in some instances fibrous substances which have not been worked into fabrics are employed for this purpose but whatever the stock may be, the

fibers usually yary in strength and in fineness. These fibrous substances for the manufacture of paper are reduced to what is known as pulp by grinding or beating them in water.

It is well known, and has long been admitted, that the process heretofore practiced for reducingrags and other fibrous matter into pulp for the manufacture of paper is defect ive. By such process the whole batch of fibers to be reduced and floating in water is caused to circulate'in the annular trough or vat of what isjtermed th pulp-engine by the rotation of the heating or grinding cylinder, and as all the fibers of a batch, with the ,water in which they are suspended, pass in their circuit an equal number of times between the concave and cylinder, where the blades or knives do the beating, it follows that although in the process a portion, more or less considerable, of the fibers may become snlficiently beaten to be of the proper consistency, that portion must still continue to be subjected to.

the heating process until the more refractory fibers become sufficiently reduced, and it follows, as a necessary consequence, that the less refractory and smaller ones aretoo much reduced. It is by reason of this defect that the paper-maker has found it so diflieult to make paper of uniform texture. Besides, this. old process necessitates the use of engines of great bulk occupying a large extent of nfloorspace, which adds greatly to the cost of a KINGSLAND,

paper-mill. To avoid the defects of this old process it has been proposed to feed or discharge a. stream of water and fibers onto the horizontal face of a rotating'wheel having a conical periphery armed with suitable beatin g or grinding blades and surrounded byatroughlike stationary curb, with its lower partof a conical form corresponding to the periphery of the wheeLland in like manner armed with beating or grinding blades, so that the fibers suspended in water should be reduced to th quired extent by passing once only between the beatin g or grinding surfaces; but this mode of procedure, so far as I am informed, has never been adopted, and is obviously defective, for the reason that it does not provide for retaining the fibers a sufficient length of time under the beating or grinding action to effect their reduction to pulp, and as the discharge is at the periphery and the heating or grinding blades in some form must extend from the inner to the outer periphery, and on conical surfaces having a vertical axis of rotation, gravity and centrifugal force will concur in carrying the fibers and water through the lands or furrows between the blades, thereby causing the fibers to escape the heating or grinding action of the blades.

The process which I have invented avoids the defects heretofore experienced, and consists in subjecting the fibers suspended in water to a beating, reducing, or grinding action in a closed reservoir containing the beaters, and provided with an aperture for the continuous'feeding in of the mixed fibers and water and an aperture for the continuous overflow of the beaten pulp, the'current of suspended fiber and water through said reservoir being induced and regulated by the conjoint action of the beatin g operation am'l'the hydrostatic pressure of the columns of induction and eduction.

The accompanying drawings represent an engine which I have invented for and which I deem suitalile for the purpose of working successfully my said improved process; and in the said drawings, B is a bed-plate, which supports the standards A A and a hollow cy- O. In a line with.

lindrical reservoir or case, the axis of this cylinder a shaft, D, is mounted in hearings in the standards A A. In a bracket, 0, on the outer standard, A, and in a boss at the middle of the outer head, d, of the cylindrical reservoir 0, set-screws b are placed in a line with the axis of the shaft D. The object of these set-screws is to adjust the nut within the reservoir and to permit it, if de-' sired, to have a regulated amount of end play for a purpose which will be I presently described. This shaft passes through a stuffingbox, S, on the inner head, d, of the reservoir 0, and extends within it toward its outer head, d This projecting end of the shaft D carries the nut, in the form of a disk, E, at right angles with the shaft and concentric with it and with the cylindrical reservoir. This disk is somewhat less in diameter and thickness than the interior of the cylinder, so as to leave between it and the heads and periphery of the cylinder a space for a current of water and rags, half stuff, or paper pulp to flow through. The outer head, (I, is made separate from and properly fitted to the inner bore of the cylinder, so that it can slide therein for adjustment, and it is connected with and secured to the cylinder by means of screw-bolts t, passing through ears to, projecting from the periphery and tapped into corresponding ears projecting from the cylinder, which is cut out at suitable places to receive the ears of the head d. Bythe means described the space between the two heads can be readily adjusted to the thickness of the nut, as also the position of the nut relatively to the two heads. The inner surface of the heads of the cylinder and the two faces of the disk are grooved in the manner represented to form cutting edges or blades of any suitable kind for working fibers into pulp, or separate blades may be inserted, those on the head at and corresponding face of the nut being made larger and deeper than on the head d and corresponding face of the nut. An orifice is made in each head of the cylinder. The orifice in the outer head, d, which is the feeding-in side of the reservoir, is connected by a pipe, F, with a tank above containingthe fibrous substance, mingled with water and ready to reduce the pulp. With the orificein theinner head, (1, which is the discharge-orifice, a pipe, G, is connected, which conducts off to a proper receptacle the -pnlp discharged from the machine, and this I discharge pipe is bolted or otherwise so secured to the case as'to admit of being set with its discharging end at different elevations.

The operation is as follows: Rotary motion is'comrnunicated to the shaft D through the pulley near its middle, and the set screws 7) are so adjusted as to allow the shaft to have a slight end-play to permit the disk E to run freely and yield slightly, and adapt itself to the beating, as I have found this best adapted to the production of uniform pulp; but, if desired, the disk E may be setso as to run without end-play. The fibrous substance and water may be now let into the feed-pipe F from a tank above, and, if the head be sufficient,

the hydrostatic pressure will force it into the cylindrical reservoir through the space 0 between the disk and the outer head, d, round the periphery of the disk, and through the space f toward the orifice of the dischargepipe G, where it will flow over into any suitable receptacle. The centrifugal action of thedisk willco-operate with the hydrostaticpressure of the column in the feed-pipe F to induce a current from the feedorifice toward the periphcry, but when thecurrent of water charged with fibers turns the pheriphery of the disk and enters the space f on. the opposite side, its passage to the discharging-orifice is retarded by the centrifugal action of the disk; but as the blades on that side are smaller than on the feeding-in side, the centrifugal force due to the rotation will predominate on the feeding-in side, and will aid in inducing a can rent toward the discharge-orifice and between the beatingsurfaces, the mechanical force bein g modified by the relative height of the ind action and eduction columns. Raising the discharging-orifice asprovided will retard the current, and lowering it will accelerate the curren t.

The current of water thus induced tends to carry the fibers between the beatingsurfaces toward the discharge-aperture, and so soon as any of the fibers are reduced to the required degree of fineness they travel with small impediment to the discharge-aperture, while the more refractory or larger fibers are held back for a longer time by the beatin g or reducing action of the blades. In this way the fibers are retained in the reservoir as long as it is necessary to reduce them to the required degree of fineness, and no longer, for so soon as they are sutficiently reduced to pass freely between the blades they follow the current and flow out instead of being retained until the more refractory onesare reduced; 1

but to effect the object contemplated by me it will be seen that is necessary to check the discharge. If, for instance, the discharge-aperture were placed at the bottom of the reservoir, and made of sufficient size to permit a free discharge of the water and fibers, the grinding action alone would not be sufficient to check or hold back the refractory fibers, and in consequence they would he carried through by the current and discharged before being properly reduced; but by placing the discharge aperture at some distance above the bottom the current is so far checked that the fibers can be retained under the beating or reducing action until properly'reduced. A gain, if thrre was no inclosing-reservoir, and the fibers and water were discharged freely at the periphery of the rotating heaters, the current would flow through the lands or furrows between the blades, and the fibers would fail to be properly reduced.

I have found the placing of the dischargeaperture from the reservoir a little above the shaft to work well, but the relative height of the feeding and discharging heads will always depend upon the tendency of the mechanical action of the machine to work the current through it. -When such tendency is great the discharginghead must be higher relatively to the feeding head, and vice versa.

The slower the motion of the current of water and fibers through -the machine at-any given velocity of the nut the finer will be the resulting pulp, the set of the rotating disk and the heads of the reservoir to each other being properly adjusted, so that by increasing or decreasing the force of the current or adj nsting'the nut and movable head the degree of fineness of'the pulp can be regulated.

The machine above described is one which I have devised for carrying my process into effect; but it will be obvious'to the'skillful mechanician, particularly if skilled in'theart of manufacturing paper, that other machinery may be made to work'the same proces.

What I claim as my invention, and desire to secure by Letters Patent, is

The process, substantially as .herein described, of reducing fibers 'to pulp for the manufacture of paper, which process consists in causing the water in which the fibers to be reduced are suspendedto pass in a current into, through, and out of a reservoir inclosiug the beaters, and provided with a feeding-in and a, discharge aperture, so that the fibers shall be retained within the said reservoir and under the action of the blades or beaters until they are sufliciently reduced and then follow the current of water to the dischargeaperture, substantially as and for the purpose specified.

' I JOSEPH K1NGSLAND,JR. Witnesses: I I

A. DE LACY, WM. H. BISHOP.

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