US1690834A - Replaceable-point excavator tooth - Google Patents

Description

Nov. 6, 1928.

1,690,834 T. RATKowsKl REPLACEABLE POINT EXCAVATOR TOOTH Filed Juli: 25, 1927 2 Sheets-Sheet 2 Patented Nov. 6, 1928.

UNITED STATES vPATENT oFFlcE.

THOMAS BATKOWSKI, OF CHICAGO HEIGHTS, ILLINOIS, ASSIGNOR T0 AMERICAN MAN- i GANESE STEEL COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF MAINE. y

BEPLACEABLE-POINT EXCAVATOB TOOTH.

Application led July 23, 1927. Serial No. 297,854.

cavator teeth have been designed with di-l vergent jaws on the point having rearwardly extending clamping tangs, and with a nose on the base adapted to enter between the jaws and recesses in the base extending rearwardly from the nose and adapted to receive the clamping tangs. In other instances, the point has been constructed in substantially the form of a `ferrule or pocket,

while the nose of the base has served as a shank to enter the pocket and to be there secured by wedges, bolts, or the like, passing through the walls of the pocket and the intervening shank. It has also been the practice to unite the jaws of the point by an integral web for the purpose of tying them together and resisting spreading under the stresses whichthe point meets in use, the nose being slotted to receive the tying web, and the jaws being in turn provided with overlapping lugs to embrace the members of.

the slotted nose to compensate for the weaknesses that would otherwise result from' their bifurcation. But in prior constructions, so far as the same are known to me, there has not been cooperation between the longitudinally remote points of 'articulation between the base and the point of a character that successfully resists relative motion between the point and the base at such places of articulation, which is essential to the prevention of weaving or lost motion between the point and the base, and essential to the prevention of excessive stresses upon the articulating parts.

The obiect of the present invention is to so vimprove the bearing of the extreme forward end of the base in the point, as well as the construction through which the point receives said end, and the bearing of the ex- \-jaws at treme rear end of the point inthe base, as well as the construction of the portion of the base which establishes said bearing, in a manner to produce an improved articulation of the members at the extremes of their overlapping or meeting portions, and establish articulations which coact one with the other in a manner to render them mutually sustaining and therefore cause each to largely relieve destructive stresses that would otherwise be imposed upon the other. The object of the invention is, further, to so coordinate the construction of the meeting portions of the point and base, at places intermediate of their extreme ends, that lost motion between the parts or weaving of the point upon the base, will be still further resisted and the end portions of the articulations will be adapted to function still more eEectively. y

rlhe invention proceeds upon the principle of constructing the point with not only divergent jaws from which extend rearwardly, clamping tangs of the kind heretofore used, but tying the sides thereof instead of at an intermediate plane, and which webs converge forwardly as do the divergent jaws so that the webs and jaws together provide the four ,sides of a tapering pocket, and the rearward- /ly presented faces of the webs afford abutment surfaces through which the point is received by the base; and the base is provided not only with theknown feature of upper and lower recesses which receive the clamping tangs of the point, with the longitudinal extension of the base between them, but has at the forward end of said extension a pyramidal nose, tapered vertically and laterally, which Vlits in the tapered pocket of the point, while the rear ends of the upper and lower recesses terminate in undercut seats for the abutment of the rear ends of the clamping tangs, and these undercut seats are specially designed, for instance, by making them of V-shaped section, to embrace the correspondingly designed rear ends of the tangs and force the latter inwardly in opposition to any spreading tendency; and, finally, the base includes in its construction cheeks integral with the forward extension of the base at the sides thereof providing the lateral confines of the tang-rebeiving recesses, between which the webs which integrally unite the tangs snugly fit, and at the same time providing vertica ly deep stiffening webs for said extension and terminating at their forward ends in abutments substantially perpendicular to the axis of assembly which receive the rearwardly presented abutting faces of the webs on the point. The result of this co-mbination of fea-tures is to cause the point,

' when drawn firmly rearward by a wedging bolt of known construction, to enter into firm rearward bearing at the end of each clamping tang and also through the vertical transverse faces of the cheeks and point websand vertical and lateral bearing of the walls o-f the tapered pocket against the surfaces ofthe pyramidal nose, with the result that all lost motion under vertical or horizontal transverse stresses is eliminated, vertical tipping stresses are converted almost wholly into shear stresses upon the wedging bolt; and lateral stresses, by reason of the close lateral fit of the clamping tangs at the rear extremity and the fit of the nose in the pocket at the forward extremity, are taken up by the cheeks and the webs of the point.

In the accompanying drawings- Figure 1 is a side elevation of a tooth constructed in accordance with the present invention, together with a portion of the lip of a dipper in section, the rear end of the base of the tooth, which will be of ordinary construction, being omitted.

Figure 2 is a section on the line 2"- of,

Figure 1.

Figure 3 is a section on the line 3"--3x of Figure 2; and

Figure 4 is a section on the line lx- 4x of Figures 1 and 3.

1 represents the lip of an excavating implement, for instance, a dipper, 2 the base of a tooth mountedupon said lip, and the separately formed tip or point of the tooth replaceably (and preferably, also, reversibly) mounted on said base. The point is co-nstructed with jaws 4 having forwardly and vertically converging inner faces 4a; webs 5 integral with said jaws at the sides thereof tying the jaws together and having their inner surfaces 5 converging laterally in the forward direction and forming with the vertically converging jaw-surfaces 4 a tapered ferrule or pocket 1%a see Fig. 4); and clamping tangs 6 extending rearwardly from the jaws 4, substantially parallel with the axis of assembly and disassembly of the point, which tangs have openings 6a to receive a clamping bolt- 7 and terminate rearwardly in specially designed abutment ends 8, for instance, ends of V-shaped section.

The base 2 is constructed with upper and lower recesses 9 that receive the tangs 6, leaving a forward longitudinal extension 10 between them, which is embraced by said tangs when in assembly; a pyramidal nose 11 p-rojecting forwardly from the extension 10 and fitting the socket 3a of the point; and vertically deep cheeks 12 integral withthe extension 10 at the sides thereof, forming the lateral confines of the recesses 9 between which the tangsA 6 snugly fit laterally, as shown in Figure 2; said cheeks terminating forwardly in abutment faces 12 substantially perpendicular to the axis of assembly, preferably in the plane of merger between the pyra-midal nose 11 and the extension 10, and receiving in longitudinal abutment the rearwardly presented faces 5b of the webs 5. Recesses 9 termina-te rearwardly in undercut seats 13 designed to conform with the abutting ends 8 of the tangs 6 and serving the function of sustaining the rear ends of the tangs not only longitudinally but transversely so that they automatically assume a firm and immovable seating under longitudinal pressure of the tooth and are pressed inwardly upon the bottoms of the recesses 9 or vertically presented surfaces of the extension 10. Clamping bolt 7, as is usual, passes through a bore 14 in the base of the tooth, in the present instance through extension 10, and bears against the forward wall of the bore 14, and the rearward walls of the openings 6a in the tangs, with the result that the tanfs 6 in the undercut 13, and the socket 3 on the pyramidal nose 11, are drawn into firm seating.

With parts constructed as above described, it will be seen that while vertical transverse stresses upon the point 3 tend to swing the point about one of the bearing ends 8 of a tang 6, as a fulcrum, such stresses are opposed by shearing resistance of the bolt 7 and by a direct bearing of a,face 4 of the socket 3 against a vertical wedging face 11a of the nose 11, and these last-named faces are at such large angles to the arc of tipping movement of that portion of the point, when a rear end of a tang is acting as a fulcrum, that spreading stress upon the tang other than that whlch is acting as a. fulcrum is very slight; moreover, such spreading stress is resisted by the hold-down face 13. When lateral stresses are imposed upo'n the point, they are opposed somewhat by shearing resistance of the bolt 7 due to the relatively large horizontal dimension of the seating faces 8 and 13; also by the snug fit of the tangs 6 between the lateral confines 12 of the recesses 9, but mainly by the faces 11b of the nose in bearing against the laterally converging faces 5Ka of the point, at one end vof the articulation in coaction with the snug-fit of the tangs, laterally, in the recesses at the other end of the articulation.

The construction herein described provides an articulation of the point with the base, which is made very firm in all transverse directions by means of bearing surfaces which are largely at the extremes of the longitudinal dimension of articulation, with the result that weaving or lost motion of the point, on the base, and consequent excessive localizing of stresses, so destructive to ordinary point mountings, are substantially eliminated.

I claim:

1. A replaceable point excavator tooth, comprising a base and a point adapted to be assembled with and disassembled from the basev substantially in the direction of the longitudinal axis of the tooth; said point being constructed with a pair of divergent` jawsand with integral lateral Webs uniting said jaws and forming therewith a nosereeeiving pocket, and with longitudinall extending clamping tangs terminatin in aseabutting ends rearwardly remote rom said pocket said base comprising upper and lower tang-receiving recesses leaving a vertically reduced longitudinal base extension between them, and terminating at their rear ends in tang-receiving undercuts having faces with which the tan s abut, inclined in the direction tovpress t e t-angs toward the bottoms of the recesses, means being provided for forcing the tangs rearwardly u on the base, cheeks on the base confining t e tangs laterally and terminating forwardly in abutments positioned to receive thev webs of the point, and a nose projecting from the base extension beyond the abutments of the cheeks and entering the pocket of thepoint. c

2. A replaceable point excavator tooth, comprising a base and a point adapted to be assembled with the base substantially in the direction of the longitudinal axis of the tooth; the base being constructed with upper and lower tang-receiving recesses, approximately parallel with sald axis, leaving between them a vertically reduced longitudinally extending body portion and terminating rearwardly in V-sliaped undercut tang abutments, vertically deep cheeks inte rral with said base extension, forming latera confines of said recesses and terminating in forwardly presented web-receiving abutments, and a vertically and laterally wedging nose integral with said longitudinal extension, rojecting beyond said cheeks; and the point bein constructed with a pair of jaws2 tying we s integral with and uniting said ]aws at the sides thereof, said jaws and webs converging forwardly in conformity with the vertical and lateral wedging of the nose, said webs on the point and web receiving abutments on the cheeks meeting continuously a dist-ance corresponding to the vertical dimension of the extension and nose in a plane substantially perpendicular to the axis of assembl clampmg tangs extending rearwardly rom the jaws of the point, embracing the forward extension of the face, fitting the recesses laterally, and conforming at their inner ends to the V-shaped abutments, and means for drawing said tangs in the direction of assembly and clamping them to the base.

Signed at Chicago Heights, Ill., this th day of July, 1927.

THOMAS RA'vrKoWsKI.

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