AU2010101063A4 - A ripper boot including a brazed high tensile tip - Google Patents

Description

1 A ripper boot including a brazed high tensile tip The present invention relates to an improved ripper boot having a brazed high tensile tip for improved strength characteristics. The preferred application of the present invention is when excavating extremely hard rock which would otherwise break conventional tools. 5 BACKGROUND OF THE INVENTION The present inventor is the owner of a number of co-pending patent applications relating to ripper boot improvements, including Australian complete patent application no. 2006284527. This patent application relates to a ripper boot having a replaceable ripping tooth. The ripping tooth includes a shank having tapered sides adapted to be press fit into a correspondingly shaped 10 cavity in the boot so that it is fixed during operation for improved performance and reduced wear and tear. The replaceable ripping tooth is angled upwardly with respect to the ripper boot carrier thereby raising the angle of attack and improving the cleaving effect. This invention is useful in any application where extremely hard and abrasive rock is to be penetrated and ripped, for example, in the extraction of precious stones such as opal, typically 15 achieved through use of a bulldozer ripper boot, or in heavier duty operations which require excavators and the like. In each of these circumstances, the ripper boot teeth, loader bucket teeth, etc, need to be strong and wear resistant enough to work the hard rock. Conventional ripper boots tend to fracture, and apply extremely high loads on machinery. The present inventor has realised an effective way of ripping through hard and abrasive 20 ground through use of a high tensile tip. The use of hardened tips on other tools is known, whereby metals such as tungsten are located at the tips of the tools to make use of its high strength characteristics. However, existing means of attachment of high tensile tips to tools results in weak spots around the tip. When such tools are used for example in mining/excavating operations, it is not uncommon for the tips to simply break off during use. When extremely hard 25 rock is encountered, explosives are sometimes used but this is not a useful alternative because of the significant cost associated with blasting operations. It is therefore an object of the present invention to overcome at least some of the aforementioned problems or to provide the public with a useful alternative.

2 It is a further object of the present invention to provide an improved ripper boot including a carrier section, an integral or replaceable tooth section, and a high tensile tip adapted to be brazed into the end of the tooth section. SUMMARY OF THE INVENTION 5 Therefore in one form of the invention there is proposed a ripping tool for excavating hard rock, said tool characterised by a carrier portion adapted to be connected to a shank of a powered vehicle and a head portion including a high tensile tip that is brazed into the end of the head portion. Preferably said head portion includes a socket and said high tensile tip includes a shaft 10 adapted to be received in said socket and brazed thereto, said high tensile tip further including an exposed end extending out from said tool head portion. In preference when said high tensile tip shaft is brazed inside said head portion socket, the exposed end extends out from the tool head portion only a short distance relative to the overall length of the tool. 15 Advantageously the longitudinal dimension of the exposed end of the high tensile tip is less than 50% of the overall longitudinal dimension of the tip. In a further form of the invention there is proposed a ripper boot characterised by: a carrier adapted to be fixedly connected to a shank of a powered vehicle; at least one tooth including a female portion at an end thereof; and 20 a high tensile tip including a male portion adapted to be received and brazed inside said female portion. Preferably said female portion is in the form of a straight walled socket and said male portion is in the form of a correspondingly shaped shaft. In preference said female portion is in the form of an inwardly tapered socket and said 25 male portion is in the form of a correspondingly shaped shaft. In preference the cross sectional shape of the shaft is square. Alternatively the cross sectional shape of the shaft is circular.

3 In preference said carrier includes a longitudinal axis, whereby the carrier, tooth and tip are disposed along the same longitudinal axis. Preferably said tooth and high tensile tip form a substantially conical shape. In preference said high tensile tip is constructed of tungsten metal. 5 Preferably said tooth is removable from said carrier means. In a yet further form of the invention there is proposed a method of manufacturing a ripping tool, said method characterised by the steps of: (a) providing a ripping tool carrier adapted to be fixedly connected to a shank of a powered vehicle, said carrier terminating in a head portion including a female socket at an end thereof; 10 (b) providing a high tensile tip including a male portion shaped to be received inside said head portion female socket, and an exposed end portion; and (d) inserting and brazing said male portion inside said head portion female socket such that said exposed end portion extends only a short distance out from said head portion. In a still further form of the invention there is proposed a method of manufacturing a 15 ripper boot characterised by the steps of: (a) providing a ripper boot carrier adapted to be fixedly connected to a shank of a powered vehicle; (b) providing a ripper boot tooth including a female portion at an end thereof; (c) providing a high tensile tip including a male portion shaped to be received inside said tooth 20 female portion; and (d) connecting said tooth and said high tensile tip by brazing the male portion into said female portion. Preferably said method includes the further step of annealing the brazement between said male and female portions. 25 In preference said carrier and tooth are integrally formed. Alternatively said tooth is removable from said carrier. BRIEF DESCRIPTION OF THE DRAWINGS 4 The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several implementations of the invention and, together with the description, serve to explain the advantages and principles of the invention. In the drawings: Figure 1 illustrates a rear perspective view of an improved ripper boot including a brazed 5 high tensile tip in accordance with the present invention; Figure 2 illustrates a front perspective view of the improved ripper boot of Figure 1; Figure 3 illustrates an enlarged, cross-sectional side view of the tooth section and brazed high tensile tip, both of which form part of the improved ripper boot of Figures 1 2; 10 Figure 4 illustrates an exploded, partially cross-sectional top view of the improved ripper boot of Figures 1-2; and Figure 5 illustrates a front perspective view of a ripper boot including a double tooth configuration for use on an excavator loader bucket. DESCRIPTION OF THE PREFERRED EMBODIMENTS 15 The following detailed description of the invention refers to the accompanying drawings. Although the description includes exemplary embodiments, other embodiments are possible, and changes may be made to the embodiments described without departing from the spirit and scope of the invention. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same and like parts. 20 The present invention relates to an improved ripper boot 10 as illustrated in Figures 1-5. The improved ripper boot 10 includes a carrier section 12, and a ripper tooth section 14 having a high tensile tip 30 brazed thereto. In operation, the carrier section 12 is placed over and conformed to fit over a ripper boot shank (not shown) of a bulldozer (not shown), or one or more excavator loader bucket shanks (not shown). Figure 6 illustrates a second embodiment of the 25 present invention where there is shown a ripper boot 15 having two tooth sections 16 and 18 associated with the one carrier section 20. It is to be understood that the present invention is not to be limited to any one application.

5 The carrier section 12 is typically held in place by utilisation of a pair of co-axially aligned retaining holes 22 and 24 located in opposed side walls 26 and 28 of the carrier section 12 respectively. A retaining pin (not shown) is adapted to extend through the holes 22 and 24 and through an aperture (not shown) associated with the available shank (not shown). It is to be 5 understood that the carrier 12 may be conformed to fit any available ripper boot or loader bucket shank, and that the present invention is not intended to be limited to only this form of attachment. As mentioned, the ripper boot includes a tooth section 14 which is shown integrally formed with the carrier section 12. This need not necessarily be the case, that is, the tooth section 10 14 could be removably attachable to the carrier section 12 by means described in the Applicant's co-pending patent applications, or by other means. The present invention proposes the use of a ripper boot having carrier and tooth sections, and a high tensile tip 30 adapted to be brazed into the end of the ripper boot tooth section 14. As mentioned in the preamble, it has been thought that ripper boots having high tensile 15 working tips fitted thereto using known means are not adequate in the working of extremely hard rock. The presentinvention proposes brazing a high tensile tip to a ripper boot. Brazing is a joining process whereby two pieces of base metal, in this case being the tooth section 14 and the tip 30, are joined when a melted metallic filler flows across the joint and cools to form a solid bond, resulting in an extremely strong joint. 20 In the embodiment shown, the tooth section 14 provides a female socket or cavity 32 at an end thereof, adapted to fixedly house the high tensile tip 30. The socket 32 includes walls 34 that taper inwardly, that is, walls that define a cross-sectional shape which is greater in size adjacent the end of the tooth section 14. It is to be understood though that the configuration of the walls is not important, for example, the socket could include straight or even curved walls. 25 Circular or square cross-sections are preferred for ease of manufacture, and it is also preferable for any sharp edges inside the socket 32 to be rounded off. The tip 30 itself is made up of a shank 36, and a head portion 38 which is essentially the part which contacts and breaks the hard rock. The shank 36 is correspondingly shaped with the socket 32, that is, it too includes tapered walls of substantially the same cross-sectional shape. 30 This allows the shank 36 to be accommodated within the female socket 32 ready for brazing.

6 As those skilled in the art would realise, to create high strength brazes, the brazement can be annealed to homogenise the grain structure with that of the metal in the tooth section and tip. The present invention is not however intended to be limited to ripper boots having annealed brazements. 5 Once the high tensile tip 30 is fixed within the socket 32, the head portion 38 extends longitudinally outwardly from the tooth section 14 in a conical manner, that is, it tapers at substantially the same angle, and terminates into a point. It is to be understood though that the shape of the tip need not necessarily be limited to this shape, for example, in some applications it is preferable for the head of the tip to be rounded, or even widened to decrease the chance of 10 wear and subsequent failure of the boot. Also, although it is preferable that the tip be constructed of tungsten, this is by no means the only material which could be used. Any material displaying similar high strength characteristics could equally well be used. As mentioned in the preamble, the present inventor has found that altering the angle of attack in some situations can result in a more effective cleaving effect. Thus, although not shown 15 in any of the drawings, the tooth section 14 could extend upwardly a predetermined angle relative to the carrier section. The high tensile tip 30 of the present invention could equally well be brazed to this type of ripper boot configuration. Figure 5 illustrates a ripper boot 15 according to a second aspect of the invention. As mentioned earlier, rather than having a single socket arrangement, there are two tooth sections 16 20 and 18 associated with the one carrier section 20. This therefore allows for two tips to be brazed into the boot 15. Such a configuration may be suitable in a number of different applications including in excavator loader buckets which require a plurality of teeth for their operation. For example, a single loader bucket may include a single shank portion (not shown) for attachment thereto of a single carrier section having a plurality of associated tooth sections. As already 25 mentioned, the present invention is not intended to be limited to any one of these configurations. In brazing a high tensile tip 30 to a ripping tooth section 14 as described above, a number of benefits are provided. Perhaps most notably, less maintenance is required on the ripper boot during operation which means that the machinery does not need to idle so often, saving considerable time and expense. The reason for this is that the tip is preferably made of a high 30 tensile metal such as tungsten which is less susceptible to wear and tear so it can be used for considerably longer periods before it becomes worn. A further benefit is the quality of the 7 ripping procedure. Hard and abrasive rock in front of the tungsten tip has been found to "explode" in its path resulting in the location of precious stones which would otherwise have been missed using conventional equipment. The result is therefore a ripper boot displaying exceptional ripping ability, increased 5 strength characteristics, increased service life, and decreased maintenance requirements. Further advantages and improvements may very well be made to the present invention without deviating from its scope. Although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to 10 the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus. In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including", i.e. the features specified may be associated with further 15 features in various embodiments of the invention.

Claims (5)

1. A ripping tool for excavating hard rock, said tool characterised by a carrier portion adapted to be connected to a shank of a powered vehicle and a head portion including a high tensile tip that is brazed into the end of the head portion. 5

2. A ripping tool according to claim 1 wherein said head portion includes a socket and said high tensile tip includes a shaft adapted to be received in said socket and brazed thereto, said high tensile tip further including an exposed end extending out from said tool head portion.

3. A ripping tool according to claim 2 wherein when said high tensile tip shaft is brazed 10 inside said head portion socket, the exposed end extends out from the tool head portion only a short distance relative to the overall length of the tool.

4. A ripping tool according to claim 2 or claim 3 wherein the longitudinal dimension of the exposed end of the high tensile tip is less than 50% of the overall longitudinal dimension of the tip. 15

5. A method of manufacturing a ripping tool, said method characterised by the steps of: (a) providing a ripping tool carrier adapted to be fixedly connected to a shank of a powered vehicle, said carrier terminating in a head portion including a female socket at an end thereof; (b) providing a high tensile tip including a male portion shaped to be received inside said 20 head portion female socket, and an exposed end portion; and (d) inserting and brazing said male portion inside said head portion female socket such that said exposed end portion extends only a short distance out from said head portion.