US520960A - Roll-bar for pulp-engines - Google Patents

Description

(No Model.)

J. H. HORNE. ROLL BAR FOR PULP ENGINES.

No 520,960. Patented June 5, 1894.

UNITED STATES PATENT OFFIcE.

JOHN H. HORNE, OF LAWRENCE, MASSACHUSETTS.

ROLL-BAR F'OR PU LP-'-ENG|NES.

SPECIFICATION forming part of Letters Patent No. 520,960, dated June 5, 1894.

Application filed January 20, 1894. Serial No. 497,502. (No model.)

1 0 all whom) it may concern:

Be it known that I, JOHN H. HORNE, a citizen of the United States, residing at Law: rence, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Roll-Bars for Pulpthey operate to such a consistency as will permit it to be converted into a sheet.

The drawings represent in Figure 1 a perspective view of a roll-bar embodying my invention. Fig. 2 is a cross-section of a roll in part with a number of bars in position. Fig.

paper web or '3 is a cross-section of a single beveled bar.

Fig. t is a modified form of a bar.

This invention, as before premised, relates to the manufacture of bars or blades for use in the rollswhich form an essential part of all paper-pulp engines, and it may be considered as relating to and constituting an improvement upon an invention described under United States Letters Patent No. 253,606, and issued in my name on July 14, 1882. The primary feature in said invention and patent consisted in constructing a bar in whichthe metal composing it was disposed equally of a median line drawn centrally and longitudinally of said bar. Furthermore in dividing the side surfaces into two portions which slope toward the opposite bounding edges of the sides. In other words the bar was made with a double bevel, which not only enabled a roll to be made interchangeable from a right-handed to a left-handed engine, but likewise assisted in maintaining the wooden strips or wedges, which are employed in looking said bars fast to the roll, in place. In the active operation of the rolls, the knives are coutinuallysubj ected to sudden lateral shocks or blows dueoto the passage of hard material between the roll and the bed-plate in the act of comminuting the stock, wood-pulp, or other material circulating about in the engine. These repeated blows serve to start the wood filling, and when this occurs the bars are frequently bent and become loose; the roll is then in need of repairs, which necessitates the stopping of the engine'with loss of time,

while the producing capacity of the mill is reduced.

The object of my invention is to produce a roll-bar of such form, that after the wooden filling or wedges are driven home positive engagement shall occur between the bar and the wedge, in'order to prevent the wedges ever starting from their places under any ordinary shocks or blows which may occur when the roll is in use. To this end I have shown a roll-bar at 2, as made from steel which is to be manufactured in strips, andthen cut into suitable lengths. This bar, as shown in crosssection has its thickest part preferably to one side of the longitudinal center andis formed with a double bevel; the lower or longer beveled surface 3 being inserted in the roll, the

upper and shorter surface 4 projecting beyond the roll proper and serving to act as the cutting edge. Between the blades are inserted strips'or wedges of wood adapted to extend longitudinally of said blades. The-upper series are indicated at 5, the lower series at 6. In order to prevent these wedges from becoming loose, I roll, out, press or otherwise form upon one side of the bar, or that part contiguous to the wedges, a step surface 7. This surface is made up in the presentinstan'ce of portions 8, 9, located in different planes and separated by shoulders 10, 10, the height of the shoulder representing the difference in the position of the planes. Hencewhen the wedges are driven into place, the woody fibers will yield suffioiently to admit of a snug fit being made, the wedges being given a taper approximating the general shape of the space between the bars. After said wedges have been driven into place the natural expansion of the wood due to the presencelof moisture will cause the wood to conform exactly to the stepssurface, and in this way fill compactly the space between the bars. WVhen this expansion has occurred,

the shoulders 10,10, then act as stops to prevent the wedges from becoming loose or drawing out, since the bars now have positive engagement with the wedges.

In the operation of keying the bars into the roll, I arrange said bars as shown in Fig. 2, that is in this particular instance only one half of the lower side portion of each bar is provided with a step surface, hence the next adjacent bar is positioned with the smooth lower side portion opposite the step-surface of the other bar, since I find in practice that a step-surface on one bar is sufiicient to hold the wedges between any two bars firmly in place. The bars are to be secured to the roll in any suitable manner now practiced, preferably however, hoops (not shown) are shrunk on the ends of the roll, while slots are cut in the extremities of the bars. Thus by causing the bars to engage the hoops said bars are fastened strongly to the roll and are then wedged in the manner set forth. However both the lower beveled surfaces may be formed with step-surfaces, and still be within the gist of my invention, since I do not wish to be limited to the precise form of the step-surface, or whether it is applied to one or both sides of a bar.

In Fig. 3 I have shown my invention as applied to a single bevel bar 2', one side being a continuous plane surface, the upper beveled surface is indicated at 4', while the lower beveled surface is formed with a step portion 7. In some instances, as shown in Fig. 4 the lower body of the bar, or that portion which is embedded in the roll, in contradistinction to the projecting part or cutting portion has no taper, but is of rectangular shape in cross-section, the step portion being raised upon it. In this particular class of bar, it is found much more difficult to retain the wood filling, since the angle between the diverging side faces of adjacent bars is much sharper, and hence my invention 1s peculiarly applicable.

What I claim is 1. Abar for pulp engines having a portion of its side surface divided into a number of separate surfaces located in different planes to create successive shoulders, which extend inwardly into the substance composing the bar, substantially as and for the purposes explained.

2. A bar for pulp-engines having a portion of its side surface divided into steps, and made up of a number of plane surfaces extending longitudinally of the bar, and a number of shoulders or risers which separate the several plane surfaces, the risers not projecting beyond the general side surface of the bar, substantially as set forth and described.

3. A bar for pulp-engine rolls having its' opposite sides tapering from a longitudinal line central or thereabout oppositely to each edge, and having a portion of its surface formed with a series of steps, which extend lengthwise of the bar, substantially as specilied and stated.

4. In combination with a roll, a series of bars, a series of plane surfaces longitudinally of each bar, a series of steps which separate the several surfaces, and wedges adapted to be inserted between the individual bars and engage the steps upon the bar, substantially as set forth.

In testimony whereof I afiix my signature in presence of two witnesses.

JOHN II. HORNE.

Witnesses:

II. E. LODGE, FRANCIS C. STANwoon.

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