USRE11616E - Cutter-head - Google Patents

Description

., 3 She etsSheet 1 S. J. SHIMER.

CUTTER HEAD.

No. 11,616. Reissued June 29,1897

3 Sheets-Sheetiif S. J. SHIMER.

CUTTER HEAD.

No. 11,616. Reissued June 29,1897p UNITED STATES PATENT OFFICE.

CUTTER-HEAD.

SPECIFICATION forming part of Reissued Letters latent No. 11,616, dated June 29, 1897. Original No. 555,742, rlatcdMarch 3, 1896. Application for reissue filed February 1, 1897. serial No. 621,579.

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lie it known that 1, SAMUEL J. SHIMER, a citizen of the United States, and a resident of Milton, in the county of Northumherland and State of Pennsylvania, have invented certainnew and useful Improvements in Cutter- ]leads; and I do hereby declare the following is a full, clear, and exact description of the in vention, that will enable others skilled in the art to which it appertains tomake and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification. The present application is for a reissue of the Letters Patent granted to methe 3d day of March, 1896, and for which I have also filed a divisional application of even date herewith, Serial X0. 621,580.

My invention relates to rotary cutter-heads for planing-machines having four sides or faces, to which plane-surfacing knives are secured in such manner as to cause the cut to be made alternately from right to left and from left to right diagonally across .the face of the board, which caused to pass within the radius of thc rotating head.

All surfaces formed by means ofrotating cutter-heads are made up of innumerable incuts or waves upon the face-surface, noticeable in proportion to their ininuten'ess, and it follows that the more varied the direction of the cut the more nearly uniform will be the surface.

' The common form of cutter-head comprises four parallel sides, to which the planer-knives are fastened, so that the cutting edges will be in parallel lines with the axis of the head, and there will be but one straight out made in the surface of the board by each knife on the head at each rotation of the cutter, irrespective of the rapidity with which the board is being fed into the line of the cut. 'lheincut therefore will show in larger or smaller wavelets upon and across the face of' the boa-rd. To avoid the making of such wavy surface, there have been plancnknivcs made upon a curve, which knives are secured to correspondingly-curved facesor seats on the cutter-head. These knives start the chip at one side of the board and follow it across the face thereof diagonally by as much as it was DIVISION A.

advanced by the feed during the making of the shear cut. These knives are very diflicult to keep in order and are otherwise objectionablc.

By my invention a shear cut is made in alternate,oppositedirections with flat 'planer knives having curved cutting edges in the form of a segment of an ellipse, which are socured tea head having trapezoidal faces alternately arranged and alternately inclined inward and outward of the axial line of the left to right diagonally across the face of the beard, thereby lessening the tendency of chipping out lumber which is cross-grained and. modifying the incuts on the surface made by a rotary cutter-head by a draw out diagonally in alternately opposite directions.

In the accompanying drawings, Figure l is an end View of a trapezoidal cutter-head made in accordance with my invention, showin g the knives or blades secured thereto. Fig. 2 is a perspective view of the cutter-head, the knives being'removcd. of one of the knives removed from the head. Fig. 4 is a perspective view of a modification Fig. 5 is a front elevation of the same, one of the knives being in place. v

In the said drawings, referring n'ow to Figs. i, 2, and 3, the reference-nu1neral1 designates a rotary cutter-head having ,a central aperture for the m andrelby which it is rotated. This cutter-head has four trapezoidal faces alternately arranged and inclining inward and outward of the axial line of the head that is to say, two opposite sides of the head are inclined from one end of the latter away from the axial. line of the head,while the other faces or sides are inversely inclined or slanting from the same end of the head, they inclining toward the axial line of the head. Each of said sides or faces is formed with. a T channel or groove 2, and Working in these grooves are screw-bolts 3, having angular heads -t. These bolts pass through slots 5 in flat knives U and are provided with washers 7 and nuts 8. The numeral 0 designates bevcutter-head and extending from 'endto end thereof. It wilkthns be seen that the knives are inclined or at an angle to the axial line Fig. 3 is a plan View of the invention, the knives being removed.

head, so as to cut from right to left and from elcd lips at the front edge of each side of the 'cdges' 2 a a more of the head, and the said faces or sides of the latter being inclined in oppositedirections and the cutting edges being curved in the form of' a segment of an ellipse,-so proportioned throughout their entire length as to lie within the surface of a cylinder of rotation. As the cutter-head is rotated the knives will alternately make a shear cut from right to left, and vice versa, diagonally across theface of the board.

. In the modification shown in Figs. 4 and 5 be at the same distance from the center of the head. "This construction, however, is claimed specifically, in a divisional application of even date herewith, Serial No. 621,580.

From the above it will be seen that to make a perfectly trucshear cut on the surface of the board .-w.i-th a trapezoidal cutter-head the knives thereof must have convex cutting In the construction last described the opposite faces of the cutter-head are convexed longitudinally on the arc of a symmetricallydisposcd ellipse, while said faceson the transverse lines are straight and parallel with each other. That is'to say, if a section be taken longitudinally through the head the outlines of said faces will appear as curved on a symmetricallydisposed ellipse and converging toward one end, while if a transverse section be taken at any point between the ends of the head the outlines will form aquadrangular polygon.

In Fig. 5 the parallel dotted lines' near the center of the head show the line of the central opening in the head for the passage of the shaft or mandrel, while the single dotted line at the lower side of said figure indicates the elliptical face symmetrically disposed with the upper elliptical face with respect to the dotted lines representing the shaft or mandrel aperture or opening.

I do not claim herein any matter shown or described in said divisional application, Serial .No. 621,580, and specifically claimed therein.

Having thus described my invention, what I claim is 1. The combination with acutter-head having four trapezoidal sides, alternately arranged and alternately inclined inward and outward with respect to'the axial line of the head, of the blades formedwith elliptical cutting edges so proportioned as to make the en-;

tire cutting edge of each knife lie within the surface of a cylinder of rotation whereby they will cut chips diagonally in opposite directions,-from side to side across a plane board, substantially as described.

2. The combination with'the cutter-head having four trapezoidal sides. alternately arranged and' alternately inclined inward to and outward from the axial line of the head, the said'sides formed with T-shaped grooves, and also formed with beveled lips extending from end to end of the head, of the slotted knives formed with elliptical cutting ,edges so proportioned as to make the entire cutting edge of each knife lie within the surface of a cylinder of rotation whereby they will cut chips diagonally in opposite directions,

from side to sideacross a plane'board, sub.- stantially as described.

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

. SAMUEL J. SIIIMER. Witnesses: Jos. ANGSTADT,

BENNETT S. J ONES.

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