US3864854A

US3864854A - Digging tooth locking device

Info

Publication number: US3864854A
Application number: US401984A
Authority: US
Inventors: Clifford J Evans
Original assignee: Individual
Current assignee: TRENCHER Corp OF AMERICA A TX CORP
Priority date: 1973-10-01
Filing date: 1973-10-01
Publication date: 1975-02-11
Anticipated expiration: 1992-02-11

Abstract

A resilient locking device for increasing the efficiency with which a digging tooth is releasably mounted within a tooth receiving pocket of excavating equipment, comprising opposed wells formed in the rearwardly disposed marginal end of the wedge portion of the tooth. A resilient block has a T-shaped cutout formed therein which receives a dovetailed wedge portion of the tooth therein. Opposed outer walls of the block have ribs disposed thereon arranged transversely of the tooth assembly. As the wedge portion of the tooth is forced into the cavity of the pocket, the ribs of the opposed legs of the block are deformed as the tooth is forced into mounted position, thereby adding resilient forces to the wedge forces which secures the wedge portion of the tooth within the cavity of the pocket.

Description

United States Patent [1 1 Evans 11 3,864,854 [451 Feb. 11, 1975 DIGGING TOOTH LOCKING DEVICE 21 Appl. No.: 401,984

[52] US. Cl 37/142 A, 403/226, 403/409,

175/413 [51] Int. Cl E021 9/28 [58] Field of Search 37/142 R, 142 A, 14] R,

Primary Examiner-Edgar S. Burr Assistant Examiner-E. H. Eicholt Attorney, Agent, or Firm-Marcus L. Bates [57] ABSTRACT A resilient locking device for increasing the efficiency with which a digging tooth is releasably mounted within a tooth receiving pocket of excavating equipment, comprising opposed wells formed in the rearwardly disposed marginal end of the wedge portion of the tooth. A resilient block has a T-shaped cutout formed therein which receives a dovetailed wedge portion of the tooth therein. Opposed outer walls of the block have ribs disposed thereon arranged transversely of the tooth assembly. As the wedge portion of the tooth is forced into the cavity of the pocket, the ribs of the opposed legs of the block are deformed as the tooth is forced into mounted position, thereby adding resilient forces to the wedge forces which secures the wedge portion of the tooth within the cavity of the pocket.

12 Claims, 8 Drawing Figures SHEET 10F 2 PATENIED FEB! 1 I975 PATENTED FEB] 1 I975 SHEET 2 [IF 2 1 DIGGING TOOTH LOCKING DEVICE FIELD OF SEARCH Reference is made to the C. J. Evans U.S. Pat. No. 3,041,752; G. A. petersen U.S. Pat. No. 3,400,476; D. M. Phillips U.S. Pat. No. 3,334,431; and KM. White U.S. Pat. No. 3,738,032. patents for the best prior art examples known to applicant BACKGROUND OF THE INVENTION Various type excavating equipment employ work engaging teeth for digging into the earth to form a cavity therein as exemplified by the digging of a ditch, for example. From time to time, the teeth lose their cutting ability and for this reason must be made easily replacable so that new teeth may be substituted therefor.

In order to make the teeth easily replaceable, it has become customary to provide a male wedge portion on the tooth which is wedgedly received by a complimentary shaped wedge receiving cavity formed within the tooth receiving pocket. This expedient occasionally permits a tooth to be inadvertently dislodged from the pocket.

Reference is made to my previous patent No. 3,041,752 which sets forth one means by which a digging tooth can be more efficiently retained within a pocket by the provision of a spring-like device placed within the cavity formed within the pocket so that the spring is deformed when the digging tooth is mounted to the pocket. The present invention provides an improvement over my prior art mounting means in that the locking device is associated with the wedge of the digging tooth rather than with the cavity formed within the pocket. Moreover, the locking device of the present invention is lower in manufacturing cost, more efficient in operation, and is unaffected by the deleterious effects encountered in ditch digging operations including corrosive atmosphere, salt water, and oxidation.

SUMMARY OF THE INVENTION This invention relates to excavation equipment and specifically to a digging tooth locking apparatus for enchancing the locking action between the wedge memher of the tooth and the wedge receiving female cavity of the pocket. The marginal butt end of the wedge of the tooth has opposed wells formed therein to impart a dovetail configuration thereinto when viewed in longitudinal cross-section. A body of resilient material has a cutout in the form of a T-shaped slot formed therein to provide juxtaposed legs which have one end portion contiguous with a joinder member and a remaining end portion freely depending away from the joinder member. Opposed exterior wall surfaces of the leg and joinder member have ribs formed thereon for compressibly deforming against the interior wall surfaces of the female cavity of the pocket.

Therefore, a primary object of the present invention is to provide improvements in digging tooth locking apparatus.

Another object of the invention is to provide a new combination including a resilient locking apparatus which removably affixes a digging tooth to a tooth receiving pocket in an improved manner.

A further object of this invention is to disclose and provide an improved means for removably locking a digging tooth to a pocket.

A still further object of this invention is to provide improvements for resiliently mounting a male wedge member to a wedge receiving female member.

Another and still further object of this invention is to provide a low cost resilient locking means by which a digging tooth can be advantageously mounted within a tooth receiving pocket.

These and various other objects and advantages of the invention will become readily apparent to those skilled in the art upon reading the following detailed description and claims and by referring to the accompanying drawings.

The above objects are attained in accordance with the present invention by the provision of apparatus fabricated in a manner substantially as described in the above abstract and summary.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective front view disclosing the present invention in one of its operative configurations;

FIG. 2 is an enlarged top plan view of a part of the apparatus disclosed in FIG. 1;

FIG. 3 is an enlarged, detailed, perspective view of part of the apparatus disclosed in FIG. 2;

FIG. 4 is a side elevational view of the apparatus disclosed in FIG. 3;

FIG. 5 is an enlarged, fragmentary, cross-sectional presentation of the apparatus disclosed in FIGS. 3 and FIG. 6 is an enlarged, fragmentary, part crosssectional view taken along line 6-6 of FIG. 1;

FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 2; and,

FIG. 8 is an enlarged, part cross-sectional, top plan view of part of the apparatus disclosed in FIGS. 1 and 6.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 illustrates a trencher bucket 9 having a plurality of digging teeth 10 operatively disposed in mounted relationship thereon.

As seen in FIG. 2, each tooth is comprised of a tip end 12 for engaging the earth and a butt end 14 which forms the terminal end of the wedge portion of the tooth. Diametrically opposed tangs l6 outwardly extend from proximity of the crest of the tooth for facilitating mounting the tooth within its pocket.

As seen in FIG. 7, together with FIGS. 2 and 6, the marginal butt end portion of the wedge portion of the tooth is provided with opposed wells 18. Each well is defined by parallel opposed side walls 20 which are outwardly opening towards the butt end portion at 22 and which terminate in a forward direction at well 24. As seen in FIG. 7, the opposed wells, when viewed in longitudinal cross-section, provide a dovetailed configuration having an enlargement 26 adjacent the butt end portion and a connecting portion 28 which is reduced in thickness an amount determined by the depth of the opposed

forward walls

30, 32.

Numeral 34 indicates the crest line where the diverging opposed walls from the tip portion of the tooth commence to coverage toward the butt end of the tooth to form the illustrated spaced sloped walls of the before mentioned wedge portion.

As seen illustrated in FIGS. 2-7, a body of resilient material 36 has a lateral joinder wall 38 from which there is directed a T-shaped slot 40 outwardly opening and made into a configuration which is complementary with respect to the before mentioned dovetail formed by the opposed wells. The slot' is defined by spaced walls 42 which enlarge at 44 for receiving enlargement 26 of the dovetail therewithin.

Transverse ribs

46 and 48 outwardly depend from the opposed exterior wall portions 50 of the two illustrated spaced legs.

Numerals

45 and 49, respectively, indicate the sloped and normal wall surfaces, respectively, which form the plurality of adjacent ribs.

As seen illustrated in FIGS. 1, 6, and 8, a weld-on mounting pocket 52 is provided with the usual

spaced legs

54 and 56 which are joined together by a

central body portion

58, 60. Spaced walls, one of which isindicated by numeral 62, define a wedge receiving cavity within which the wedge portion of the tooth is wedgedly received. The walls 64 of the pocket slope towards each other. The pocket is welded onto structure 66 of the bucket in the illustrated manner of FIGS. 1 and 6. Further details of the pocket are set forth in my before cited patent. It should be realized that the pocket 52 can be welded onto any number of different digging implements, the trencher bucket 9 being merely one of several different examples.

The resilient body 36 can be made of rubber, plastic, or other resilient or deformable material. in the preferred embodiment, the wedge is a sawed section of a longitudinally extending molded strip of carbon black reinforced vulcanized rubber. The interior marginal leg portion of the body is placed into operative position within the opposed wells by forcing the outwardly opening slot portion of the cutout over the enlargement 26 of the dovetail so that the horizontal bar portion of the T at 44 receives the enlargement therewithin, with the juncture portion abuttingly engaging butt portion 14 of the wedge portion of the tooth.

When it is desired to install the digging tooth of the present invention within the cavity 64 of pocket 52, the old worn tooth is driven from the pocket by inserting a suitable tool rearwardly into the pocket cavity at 58 so that the old tooth can be driven from its pocket. The new tooth is forced into position by impacting the opposed tangs with sufficient force to suitably seat the wedge portion of the tool within the wedge shaped cavity of the pocket in the illustrated manner of HO. 6.

As seen in comparing the illustrations of FIGS. 6 and 7, the outwardly directed ribs of the body of resilient material is deformed as it is placed into compression because of the co-acting of complementary action of the pocket cavity relative to the converging opposed faces of the wedge portion of the tooth.

It will be noted that the ribs are directed forwardly toward the tip portion of the tooth, thereby enabling the wedge portion of the tooth to be mounted within the cavity with much less force as compared to the force required for withdrawing the tooth therefrom because of the forwardly directed ribs. The body of resilient material not only releasably attaches the wedge to the pocket but additionally provides the unforeseen advantage of bringing about a dampening action which precludes chattering and other harmonic vibrational motion from loosening the tooth from its pocket. The unexpected advantage of the locking action of the forwardly directed ribs in cooperation with the pocket cavity walls greatly enhances the new combination over other prior art locking means.

The low cost of the resilient retaining member to gether with the simple means by which the wedge portion of the digging tooth can be modified into accordance with the presentinvention causes the present combination to beespecially desirable to those skilled in excavating equipment.

l claim:

1. Locking device for releasably mounting a digging tooth within a tooth within a tooth receiving pocket of excavation equipment comprising, in combination:

a body of resilient material, said body having opposed wall surfaces, ribs formed on said opposed wall surfaces, a T-shaped cutout forming spaced co-extensive legs with each leg providing one of said opposed wall surfaces, the juncture of said legs forming a portion of said T-shaped cutout;

a digging tooth and a tooth mounting pocket; said tooth having a tip portion for engaging the earth and a wedge portion for engaging the pocket; opposed wells formed in a marginal free end portion of said wedge portion which causes said marginal free end portion of said wedge portion to be dovetail in cross-sectional configuration, said dovetail being of a size to be received within said T-shaped cutout,

so that said ribs, when said wedge portion is forced into said pocket, are compressibly deformed in a manner to increase the wedge action between the tooth and the pocket.

2. The combination of claim 1 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge; and,

said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion.

3. The combination of claim 1 wherein said ribs have a sloped wall portion and a normal wall portion, said normal wall portion being disposed normally to each leg; said sloped wall portion being directed forwardly towards said tip portion.

4. The combination of claim 1 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge;

said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion;

said ribs have a sloped wall portion and a normal wall portion with the latter being disposed normally to each leg and the former being directed forwardly towards said tip portion.

5. In combination with a digging tooth and a tooth receiving pocket of excavating equipment, a locking device for increasing the force with which the tooth is removably affixed to the pocket;

said locking device being a resilient member having an outwardly opening cutout which forms spaced legs, said legs being joined at one end by a juncture member, said legs having a free end portion opposed to said juncture member; said cutout being enlarged adjacent said juncture member; ribs formed on an external wall of said legs;

said digging tooth having a wedge portion and a ground engaging tip portion; said pocket having a cavity formed therein which is of a configuration respective to said wedge portion for wedgedly receiving said wedge portion therein;

means forming a well in the marginal terminal end portion of said wedge portion; said well having a configuration respective to said cutout of said locking device so that part of the leg of the locking device can be received within the well;

said ribs of said resilient member extending outwardly of said wedge portion to be deformed when the wedge of said digging tooth is forced into the cavity of said pocket.

6. The combination of claim 5 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge;

said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion. 7. The combination of claim 5 wherein said ribs have a sloped wall portion and a normal wall portion with the last wall portion being disposed normally to each leg; said sloped wall portion being directed forwardly towards said tip portion.

8. The combination of claim 5 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge;

9. An elongate male wedge member, a wedge receiving female member having converging side walls for wedgedly receiving said male wedge member therein;

said male wedge member having a forward end and a butt end, said butt end being removably received within said female member with said forward end depending away from said female member;

said male wedge member having opposed sides converging toward said butt end thereof; a well formed within said opposed sides at a marginal end portion of said butt end, each said well jointly forming a configuration which is dovetail in longitudinal cross-section at said marginal end portion of said butt end of said male wedge member;

a body of resilient material having opposed exterior side walls, a cutout formed in said body of resilient material in the form of a T-shaped slot to provide juxtapositioned legs contiguous at one end portion with a joinder member; each leg having an interior wall surface adjacent to the remaining leg, one of said opposed exterior side wall also forming an exterior side wall of one said leg; said T-shaped slot being of a configuration to receive said dovetail cross-section of said male wedge member therein with said exterior side walls extending outwardly of said opposed sides converging toward said butt end, so that the exterior side walls resiliently engage the female member as the male wedge member is forced into engagement with the female member.

10. The apparatus set forth in claim 9 and further including transverse ribs formed on said opposed exterior side walls;

said male wedge member having opposed side walls contiguous with said opposed sides; and, said wells being spaced from said opposed side walls of said male wedge member.

11. The apparatus set forth in claim 9 wherein said ribs have a sloped wall portion and a normal wall portion, said normal wall portion being disposed normally to each leg; said sloped wall portion being directed forwardly towards said tip portion.

12. The apparatus set forth in claim 9 and further including transverse ribs formed on said opposed exterior side walls;

said ribs having a sloped wall portion and a normal wall portion, said normal wall portion being disposed normally to each leg; said sloped wall portion being directed forwardly towards said tip portion;

said male wedge member having opposed side walls contiguous with said opposed sides; said wells being spaced from said opposed side walls of said male wedge member, so that said opposed exterior side walls engage only a portion of the converging walls of the female member.

Claims

1. Locking device for releasably mounting a digging tooth within a tooth within a tooth receiving pocket of excavation equipment comprising, in combination: a body of resilient material, said body having opposed wall surfaces, ribs formed on said opposed wall surfaces, a T-shaped cutout forming spaced co-extensive legs with each leg providing one of said opposed wall surfaces, the juncture of said legs forming a portion of said T-shaped cutout; a digging tooth and a tooth mounting pocket; said tooth having a tip portion for Engaging the earth and a wedge portion for engaging the pocket; opposed wells formed in a marginal free end portion of said wedge portion which causes said marginal free end portion of said wedge portion to be dovetail in crosssectional configuration, said dovetail being of a size to be received within said T-shaped cutout, so that said ribs, when said wedge portion is forced into said pocket, are compressibly deformed in a manner to increase the wedge action between the tooth and the pocket.

2. The combination of claim 1 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge; and, said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion.

4. The combination of claim 1 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge; said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion; said ribs have a sloped wall portion and a normal wall portion with the latter being disposed normally to each leg and the former being directed forwardly towards said tip portion.

5. In combination with a digging tooth and a tooth receiving pocket of excavating equipment, a locking device for increasing the force with which the tooth is removably affixed to the pocket; said locking device being a resilient member having an outwardly opening cutout which forms spaced legs, said legs being joined at one end by a juncture member, said legs having a free end portion opposed to said juncture member; said cutout being enlarged adjacent said juncture member; ribs formed on an external wall of said legs; said digging tooth having a wedge portion and a ground engaging tip portion; said pocket having a cavity formed therein which is of a configuration respective to said wedge portion for wedgedly receiving said wedge portion therein; means forming a well in the marginal terminal end portion of said wedge portion; said well having a configuration respective to said cutout of said locking device so that part of the leg of the locking device can be received within the well; said ribs of said resilient member extending outwardly of said wedge portion to be deformed when the wedge of said digging tooth is forced into the cavity of said pocket.

6. The combination of claim 5 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge; said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion.

7. The combination of claim 5 wherein said ribs have a sloped wall portion and a normal wall portion with the last wall portion being disposed normally to each leg; said sloped wall portion being directed forwardly towards said tip portion.

8. The combination of claim 5 wherein said wedge has opposed converging wedge forming faces and opposed sides defining the width of the wedge; said wells being spaced from said opposed sides and outwardly opening rearwardly of said tip portion; said ribs have a sloped wall portion and a normal wall portion with the latter being disposed normally to each leg and the former being directed forwardly towards said tip portion.

9. An elongate male wedge member, a wedge receiving female member having converging side walls for wedgedly receiving said male wedge member therein; said male wedge member having a forward end and a butt end, said butt end being removably received within said female member with said forward end depending away from said female member; said male wedge member having opposed sides converging toward said butt end thereof; a well formed within said opposed sides At a marginal end portion of said butt end, each said well jointly forming a configuration which is dovetail in longitudinal cross-section at said marginal end portion of said butt end of said male wedge member; a body of resilient material having opposed exterior side walls, a cutout formed in said body of resilient material in the form of a T-shaped slot to provide juxtapositioned legs contiguous at one end portion with a joinder member; each leg having an interior wall surface adjacent to the remaining leg, one of said opposed exterior side wall also forming an exterior side wall of one said leg; said T-shaped slot being of a configuration to receive said dovetail cross-section of said male wedge member therein with said exterior side walls extending outwardly of said opposed sides converging toward said butt end, so that the exterior side walls resiliently engage the female member as the male wedge member is forced into engagement with the female member.

10. The apparatus set forth in claim 9 and further including transverse ribs formed on said opposed exterior side walls; said male wedge member having opposed side walls contiguous with said opposed sides; and, said wells being spaced from said opposed side walls of said male wedge member.

12. The apparatus set forth in claim 9 and further including transverse ribs formed on said opposed exterior side walls; said ribs having a sloped wall portion and a normal wall portion, said normal wall portion being disposed normally to each leg; said sloped wall portion being directed forwardly towards said tip portion; said male wedge member having opposed side walls contiguous with said opposed sides; said wells being spaced from said opposed side walls of said male wedge member, so that said opposed exterior side walls engage only a portion of the converging walls of the female member.