US3203488A - Ripper tooth - Google Patents

Description

Aug. 31, 1965 J. EASTWOOD 111 3,203,488

RIPPER TOOTH Filed Sept. '1, 1962 s Sheets-Sheet 1 JOSEPH EASTWOOD III INVENTOR.

BY fliZAyw w ATTORNEYS Aug. 31, 1965 J. EASTWOOD m RIPPER TOOTH 3 Sheets-Sheet 2 Filed Sept. 7, 1962 JOSEPH EASTWOOD III INVENTOR.

ATTORNEYS 31, 1965 J. EASTWOOD in 3,203,488

RIPPER TOOTH Filed Sept. 7, 1962 5 Sheets-Sheet 3 FIG. 5

FIG.7

FIG. 4

FIG.6

JOSEPH EASTWOOD III INVENTOR BY @AWMW ATTORNEYS United States Patents.

3,293,488 *RlPPER TO'OTI-I Joseph Eastwood III, Hayward, Calif., assignor to Pacific States Steel Corporation, Union City, Calif, a corporation of California Filed Sept. 7, 1962, Ser. -No. 222,012 1 'Claim. (Cl. 172-713) This invention relates to ripper tooth assemblies and more particularly to such assemblies including a mounting shank and a replaceable ripper tooth.

Ripping teeth have been used in the past to scarify earth structures such as rock and the like, by dragging the tooth below the surface of the earth with heavy machinery. Since the teeth are used on granite and other rock, it is apparent that they are subjected to extreme wear and must, from time to time, be replaced. At the same time the teeth must be strong enough to withstand the extreme digging action to which they are put.

Since the teeth must be replaceable, various means have been devised for securing individual teeth onto the shank. The teeth usually have a relatively fiat nose portion to assist in the digging action. Thus they must be aflixed to the shank such that they maintain a definite orientation.

In the prior art the teeth are usually made with a plug portion having one or more flat or flattened sides which cooperate with a similarly shaped socket in the shank to prevent twisting. Although flat or flattened plugs and sockets clearly prevent twisting, manufacturing problems are presented. In order for the tooth to transfer to the shank the various vertical and horizontal thrusts encountered during digging operations, the tooth must fit relatively well within the shank. While it is well known that forgings provide considerably greater strength than cast materials, the dimensional tolerance of a flattened plug is substantially less when forged than when cast. Consequently, if a flattened plug and socket arrangement were employed to connect the tooth to the shank, it is almost imperative that the tooth be cast. These machining operations are extremely expensive compared to the cost of the tooth itself and consequently forged teeth have not been commercially exploited to any great extent.

In view of the above, it is a general object of the present invention to provide an improved tooth for earth working devices.

It is a more particular object of this invention to provide an improved tooth for earth working devices which is readily replaceable and further which may be conveniently forged.

It is still another object of this invention to provide a tooth of the aforementioned character wherein a relatively tight fit exists between the tooth and the mating shank section.

These and other objects and features of the invention will become more clearly apparent upon a review of the following description in conjunction with the accompanying drawing, in which:

FIGURE 1 is an elevational view showing a digger tooth in accordance with the invention, as found in normal use;

FIGURE 2 is an enlarged perspective and exploded view of the digger tooth and vertical shank as shown in FIGURE 1;

FIGURE 3 is a further enlarged detailed side elevational view of the tooth and shank shown in FIGURE 2;

FIGURE 4 is an enlarged top plan view of the tooth shown in FIGURES 2 and 3;

FIGURE 5 is an end view of the tooth shown in FIG- URE 4;

3,203,488 Patented Aug. 31, 1965 FIGURE 6 is a side elevational view of the tooth shown in FIGURE 4;

FIGURE 7 is a sectional view taken along the line 7-7 of FIGURE 6; and FIGURE 8 is a side elevational view similar to that of FIGURE 3 but showing a wear boot in addition thereto.

Referring to FIGURE 1 there is shown a ripper tooth assembly 11 including a vertical shank 13 and a ripper tooth 15. The vertical shank of the assembly is shown connected as at 17 to a first tractor-like vehicle 19. A second tractor-like vehicle 21 is shown connected to the first with a tow bar 23 while a third vehicle 25 is shown behind the first whereby it is in a pushing relationship with respect to the assembly 11.

As the various vehicles are traveled along the surface 27 of the ground which may be rock or the like, the digger tooth 15 is forced through the earth itself leaving a cut 29. In practice the digger tooth 15 may extend several feet below the surface of the earth and frequently its path through the earth is assisted by periodic bumping from the rearward vehicle 25 rather than a continuous push. Thus, it is apparent that the tooth 15, as well as the vertical shank 13, are subjected to extreme stresses such that the tooth 15 itself must be constructed of particularly strong material.

As can be seen in FIGURE 2 and also in FIGURE 3, the shank 13 includes a socket member 31 secured at the lower end thereof by a weld 32 or the like. The forward face 33 of the socket member includes generally parallel shoulders 35 and 37 and a frusto-conically shaped socket 39. A bore 41, coaxial with the frustoconical socket 39, extends through the shank 13 land the socket member 31.

The ripper tooth itself, as can be better seen in FIG- URES 4-7, includes a digging portion formed by side walls 43 and 45 joined together by a web 47 which terminates in a forward edge 49. The rear of the web 47 expands as at 51 to provide, in conjunction with the rear portions of the side Walls 43 and 45, a flange having relatively parallel surfaces 53 and 55.

Rearward of the surfaces 53 and 55 is a frusto-conical shaped plug 57 corresponding in shape and size with the frusto-conical socket 39. The rear of the plug 57 is tapped as at 59 to receive a threaded shaft 61 (FIG. 3). The threaded shaft 61 extends through the bore 41 and, in conjunction with the nut 63 and washer 65, serves to retain the plug 57 tightly in the socket 39. The parallel faces 53 and 55 cooperate with the shoulders 35 and 37 whereby twisting of the tooth within the socket is prevented.

In the tooth shown, it is apparent that side thrust as well as the vertical thrust on the tooth 15 are transferred to the shank 13 through the medium of the frusto-conical plug and socket. It is likewise apparent then that the plug 57 must fit securely within the socket 39 such that these thrusts will not cause vibration or excessive shock, against the shank itself. Twisting movement of the tooth, on the other hand, is prevented by means of the shoulders 35 and 37 in cooperation with the parallel edges 53 and 55.

Since the portions of the tooth as well as the socket which require the most accurate fit are merely conical type surfaces, it is apparent that forging is an economic and feasible method of manufacture, even if some reaming is required. Consequently, a high strength replaceable tooth is provided. Since the shoulders 35 and 37 as well as the generally parallel surfaces 53 and 55 merely prevent twisting movement on the tooth, it is clear that a high degree of accuracy is not required on these surfaces. The manufacturing tolerances of normal forging operations are entirely suitable with no requirement of machining.

Referring to FIGURE 8, a similar ripper tooth as sembly is shown with the exception that a wear boot 67 is provided in order to prevent excessive wear of the socket member 31. The wear boot 67 may be fitted over the socket member 31 and welded as at 69 to the shank 13.

I claim:

A ripper tooth assembly comprising a shank, a socket member carried on the end of the shank, said socket member including a forwardly facing upstanding face, a pair of generally parallel shoulders extending forwardly beyond said face, a frusto-conical socket opening formed in said socket member and extending rearwardly of said face, a digger tooth carried by said socket member, a frusto-conical plug formed at the rear of the tooth and having a size and shape comparable to that of the socket opening for cooperative engagement with the wall surface of said opening to transmit horizontal and vertical thrust thereto, means for drawing said plug into said socket opening and for retaining said plug tightly in said opening, said tooth further including a digging portion formed at the forward end thereof and subject to receiving twisting thrusts tending to rotate the tooth about the axis of said plug, said digging portion including References Cited by the Examiner UNITED STATES PATENTS 1,395,048 10/21 McKee 37-142 1,540,314 6/25 Clark 37l41 2,847,921 8/58 Heckathorn 172-699 2,919,506 1/60 Larsen 37142 References Cited by the Applicant UNITED STATES PATENTS 2,385,395 9/45 Baer.

SAMUEL KOREN, Primary Examiner.

25 A. JOSEPH GOLDBERG, LUCIE H. LAUDENSLA- GER. Examiners.

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