Ripper attachment for earth-working equipment

A ripper tool having a generally inverted "Y" shaped arrangement for use with earth-working equipment such as backhoes, excavator buckets, tractors, etc. The tool comprises a straight shank including means for sturdy attachment to the earth-working equipment and two teeth angled out from said shank towards the ground, the angle between said teeth being from about 38.degree. to 62.degree.. This bifurcated angled arrangement has been found to be both more effective and longer wearing than single tooth rippers or rippers using two or more parallel teeth.

BACKGROUND OF THE INVENTION 
This invention relates in general to earth working equipment and, more 
specifically, to an improved ripper tool for use with excavating 
equipment. 
Conventional backhoes, using a digging bucket, often encounter poor soil 
conditions making digging very difficult. Often the ground to be worked is 
rocky, frozen or simply very well-packed and dense, such as compacted 
adobe, decomposed granite roads, etc. In such cases, some means must be 
provided to break up the hardened ground before a backhoe bucket or other 
excavating means can be used to cmplete the excavation. 
Backhoe buckets or scoops often have a plurality of short teeth along the 
bucket edge. Since a number of cutting edges contact the ground at the 
same time, penetration into hard ground is very limited. Attachments 
having one or a few longer teeth are sometimes used to improve digging 
effectiveness. 
A wide variety of cutting and ripping attachments have been designed for 
use with or attachment to backhoes or other excavating means. In order to 
concentrate the penetrating or earth breaking force of the ripper, many 
prior art devices utilize a single ripper tooth as the earth breaking 
attachment. While often effective, a single tooth only penetrates the 
ground over a relatively narrow area. Stresses induced in the single tooth 
and in the means attaching it to the earth-working equipment often result 
in premature failure. A single tooth also tends to wear rapidly and 
require frequent replacement. 
Using two or a few long parallel teeth has resulted in greater wear 
resistance, but decreased ripping effectiveness. In general, a single 
tooth gives greatest penetration but a short effective life while plural 
teeth provide a longer useful life with lower efficiency. 
Thus, there is a continuing need for a ground ripping tool for excavating 
equipment which combines effective ripping with long wearing 
characteristics. 
It is, therefore, an object of this invention to provide a ripping tool 
which more rapidly breaks up hard, dense soil. 
Another object of this invention is to provide a ground ripping tool having 
a longer useful life. 
A further object of this invention is to provide a ground ripping tool 
adapted for use with a variety of earth-working machines. 
SUMMARY OF THE INVENTION 
The above objects, and others, are obtained by a ripper tool having an 
approximately "Y" shaped arrangement, the shank of said tool having means 
for attachment to an earth-working machine, such as a backhoe bucket, and 
each tooth terminating in an earth engaging tip. Preferrably the two teeth 
lie at an angle of about 30.degree. to 62.degree. to each other, equally 
on each side of the shank. Optimum results have been obtained at an angle 
of about 50.degree.. Preferrably, each tip has a chisel-like shape, the 
edge lying approximately perpendicular to the plane of the plate-like 
teeth.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to FIG. 1, there is seen a perspective view, from the back, 
of an excavation bucket 10 of the sort which could be carried by a piece 
of conventional earth-working equipment (not shown) such as a backhoe. 
While bucket 10 may have a series of teeth 12 along the front edge of the 
bucket, as discussed above such teeth are useful only with relatively soft 
earth. Bucket 10 is supported on the earth-working machine by a bar 14. A 
articulated arm, consisting of a pair of spaced parallel plates 16 and 
spaced parallel bars 17, is connected to operating means 19 movably 
attached to the machine. The articulated arm is moved by means 19 to pivot 
bucket 10 around pin 18 between bucket 10 and bar 14. The pin 20 which 
fastens bars 17 to bucket 10 passes through a hole 22 (as seen in FIGS. 2 
and 3) in shank 24 to secure the ripper tool 26 to bucket 10. 
A pair of rings 28 (FIGS. 2, 3 and 4) are secured, such as by welding, 
around each end of hole 22. The rings have a sufficient thickness to 
provide a snug fit between bars 17 and may be hardened, if desired, to 
provide a long wearing bearing surface. Bushings 30 (FIG. 3) of selected 
internal diameter may be placed in hole 22 to accommodate different 
diameter pins 20. 
Ripper tool 26 is prevented from rotating about pin 20 by the upper end 32 
of shank 24 which bears against the end of rod 14, as seen in FIG. 1. The 
shape of end 32 will be selected to fit the specific bucket 10 or other 
device with which the ripper tool 26 is to be used. 
A pair of angularly displaced ripper teeth 34 are secured to shank 24 along 
a line 36 by any suitable means, such as welding. Of course, the entire 
tool 26 could be forged and/or machined from a single piece of steel. Each 
tooth 34 preferrably has a flat plate configuration as shown, tapering to 
a point at the lower end. Of course, teeth 34 could be more rounded, 
triangular, or any other suitable configuration. 
While the sharp tips of teeth 34 could be formed as part of the teeth, for 
longest wear replaceable tip inserts 38 are preferred. Inserts 38 may be 
steel, tungsten carbide or any other suitable material. Inserts 38 may 
have stems (not shown) inserted into holes in the ends of teeth 34, may be 
welded in place, etc. 
While inserts 38 may have any suitable shape, best results have been 
obtained with wedge or chisel shaped tips having an edge approximately 
perpendicular to the plane of the plate-shaped teeth 34. 
The angular relationship of teeth 34 has been found to be critical to 
obtaining optimum performance. While the reason this ripper tool 26 is 
superior to prior tools having single teeth or spaced parallel teeth is 
not fully understood, it is thought that at times both teeth 34 work 
simultaneously together and at other times the assembly rocks slightly, so 
that each tooth alternately and cyclically digs in. Thus, this tool 
automatically adjusts to ground hardness. In any event, best results with 
longest wear is obtained where the angle between teeth 34 (as seen in FIG. 
4) is from about 30.degree. to 62.degree., with optimum results at about 
50.degree., each tooth at an equal angle to the centerline symbolized by 
main shank 24 in FIG. 4. 
An alternative embodiment of the ripper of this invention is shown in FIGS. 
5 and 6. In some cases, it is desirable to rip a relatively narrow slot in 
the ground during part of an earthmoving operation. As seen in FIGS. 5 and 
6, a third tooth 150 may conveniently be included, mounted centrally 
between first and second teeth 134 on ripper tool 126. Ripper tool 126 is 
basically similar to tool 26 shown in FIGS 1-4, being mountable on a 
bucket or other device by a pin passing through hole 122 between rings 
128, with main shank 124 and shoulder 132 engaging the support means. Each 
main and central tooth preferrably has a hardened tooth insert 138 and 
152, respectively. 
Either first and second teeth 134 together or third tooth 150 can be 
independently brought into ground contact by moving the support means in a 
manner rotating tool 126 about the pin in hole 122. With the tool rotated 
forward, only third tooth 150 will engage the ground, while rotating the 
tool rearwardly will bring first and second teeth 134 into ground 
engagement. While it is possible to bring all three teeth into ground 
contact at the same time with two teeth in advance of the third tooth, 
this is generally not desirable, since this arrangement would have many of 
the multi-tooth ripper problems discussed above. 
While specific orientations and overall configuration details are provided 
in the above description of a preferred embodiment, these may be varied 
within the scope of this invention with similar results. For example, the 
location of hole 22, the shapes of shank 24 and shank end 32, and the 
overall curve of the tool may be caried to fit the specific piece of 
earth-working equipment with which the ripper tool is to be used. In 
general, any mounting arrangement may be used where, by operating the 
conventional earth-working machine, teeth 34 can be brought into forceful 
contact with the ground at angles between about 20.degree. and 90.degree.. 
Other variations, applications and ramifications of this invention will 
occur to those skilled in the art upon reading this disclosure. These are 
intended to be included within the scope of this invention, as defined in 
the appended claims.