Patent Application
20070243029
1. Field of the Invention
The present invention generally relates to abrasive grit structures used in the grinding and shaping of various material, and more particularly, relates to a continuous circular shearing edge composed of brazed carbide grits for use on a cutting and/or grinding tool for non metal materials and compositions.
2. Description of Related Art
Abrasive grit tool structures have been known for numerous years. Generally, the abrasive grit tool structures include devices such as grinding wheels, hand tools, and the like which generally have an outer grit particle surface which is used to remove portions of a work piece for shaping and finishing a work piece. In many prior art structures, abrasive grits have been attached to tool surfaces by placing a single layer of grit particles on a tool form and then binding the grits to the tool by using a brazing metal or by an electro plating coating which grips the grit particles. These structures along with other types of structures have the disadvantage of that the resulting tool may have grits of widely varying heights, erratic grit edges, flat spots or other irregular surfaces which tend to present an uneven grinding surface with relation to the work piece. It should be noted that in grinding structures the desired effect is to present the abrasive grits to the work piece at a uniform level in order to most effectively shape the work piece. Many of these prior art grinding wheels and the like fail to meet this objective.
Many prior art grinding wheels are generally made from electroplating or brazing of materials onto the outer surface of the structures. Other prior art grinding wheel structures have been produced by either pressure forming a grinding wheel on a mold or grinding surfaces that have been added to tools by placing an individual tool on the mold and using pressure molding and brazing procedures to attach the grinding surface to a substrate mold surface. However, many of these prior art procedures are costly, time consuming, and require special equipment that is hard to manufacture and maintain.
Furthermore, many of the prior art grinding wheel structures generally do not provide adequate space between the grinding particles. This results in diminished use for the lifetime of the tool due to particles of the work piece being lodged between the grit particles or extending over the grit particles such that contact between the individual grit particles and the work piece is reduced thereby inhibiting the grinding action and efficiency of the wheel.
In the prior art nearly all rubber and other elastomers have only been mechanically worked by various rasp shredding and abrading tools. Many of these prior art tools tend to be very inefficient as compared to the present invention. Many of these prior art devices waste much of the power input to friction caused heat, smoke, reverted material, and abraded surfaces. Some prior art grinding tools have the cutting edge widths run substantially parallel to the axis of rotation. Furthermore, other prior art devices have minimal and insufficient edge rakes and clearances such that whenever these tools are used on elastomers the edges cause excessive deformation into and friction from contact with the work pieces which have relatively great elastic recovery that rubs on the edge rake faces and edge clearances. The results of many of these prior art wheels is not satisfactory work pieces such as covered rollers.
Therefore, there is a need in the art for an improved grinding wheel or tool that includes a plurality of continuous parallel edges arranged at a predetermined angle on the tool work face. These edges will be capable of grinding non-metallic materials in a cost effective long term package. There also is a need in the art for a grinding wheel that will perform more efficiently and reduce the amount of friction encountered during the grinding of many non-metal materials. Furthermore, there is a need in the art for a grinding wheel or tool that has increased positive edge rakes and clearances and the use of more effective edge shearing angles for enhanced mechanical removal efficiency of the material being ground by the grinding wheel.
One object of the present invention is to provide an improved grinding wheel for use in grinding down non-metal materials.
Another object of the present invention is to provide an improved edge design to be molded with various hard grit materials.
Yet a further object of the present invention is to provide a grinding tool having a plurality of parallel edges that are oriented in a predetermined direction on the tool face.
Still a further object of the present invention is to provide a grinding wheel with a plurality of parallel edges that have increased cutting clearance, positive cutting edge rakes, edge clearance angles and edge shearing angles to the axis of rotation of the tool.
Still another object of the present invention is to provide a grinding wheel that substantially reduces the inherent friction and deformation of the materials being worked.
Still another object of the present invention is to provide a plurality of parallel edges on a tool that may have interrupted continuous edges defined by voids along a common edge line.
Still another object of the present invention is to provide a grinding tool for use in grinding non-metal materials at a lower cost with reduced maintenance.
Still another object of the present invention is to provide a grinding wheel that will operate with less friction while also increasing the durability of a grinding wheel.
To achieve the foregoing objects, a tool for grinding non-metal materials is disclosed. The tool includes a plurality of molded parallel edges. The edges are brazed to a working face of the tool with an alloy. The edges have a predetermined rake angle and edge clearance and also extend a predetermined height from the tool.
One advantage of the present invention is that it provides an improved edge cutting structure for a grinding tool.
Still another advantage of the present invention is that it provides an improved grinding wheel for use in grinding down metal materials.
Still another advantage of the present invention is that the parallel edges provide a more efficient grinding wheel.
Still another advantage of the present invention is that the continuous edges provide less friction caused heat during the grinding of non-metal materials.
Yet a further advantage of the present invention is that the edges are parallel and continuous or interrupted with predetermined voids therein.
Still another advantage of the present invention is that the use of numerous parallel edges allows for the ability to space the edges at predetermined intervals which allows controlled removal rate and surface finish from the revolving wheel face.
Another advantage of the present invention is the use of interrupted continuous edges by the use of predetermined width voids which will serve to increase removal efficiency and to obtain various desired surface finish smoothness or roughen conditions on the worked surfaces.
Other objects, features and advantages of the present invention will become apparent from the subsequent description and the appended claims, taken in conjunction with the accompanying drawings.
Referring to the drawings, the present invention of continuous shearing edges 10 composed of brazed carbide grits for use on a tool or grinding wheel 12 are shown. It should be noted that the continuous edges 10 are selectively attachable to a tool surface or a tool 12 such as a grinding wheel or the like. Applicant has developed various methods and apparatuses for connecting or molding teeth like structures to tool or surfaces and the present invention can be used with any of the Applicant's previous inventions and therefore, the Applicant hereby incorporates by reference prior U.S. Pat. Nos. RE 35,182; 4,916,869 and 6,821,196.
The edge structures 10 according to the present invention comprise pre-formed continuous or interrupted shearing machining edges that are composed of hard substance grits that are brazed together onto steel wheels or other tool or base members. The edges 10 may be interrupted by voids 14 between teeth 16 of the edges 10. The edges 10 have hard substance grits arranged therein and these grits may include various metal carbides, borides, nitrides, and diamond and other like hard materials. The shearing edge structures 10 of the present invention are preformed and may be continuous or interrupted by voids 14 to make edge teeth 16. The edges 10 may be made parallel to one another and can also be positioned to selective shearing angles. The preformed edges are molded from the processes and methods described in the previous U.S. patents of the Applicant incorporated by reference above. After the preformed edges 10 are created, they are positioned on a steel tool base or grinding wheel 12. A hard filler material such as a metal is used to infiltrate and braze the grits to their preformed edge constructions and to the base of the tools 12 that are heated in a controlled atmosphere furnace. Many of the prior art magnetic and molded mechanical teeth are very effective abrading tools for use on all elastomers and other non-metals, however they do not perform with the efficiency of the machining edge structures 10 of the present invention. The present invention enables the selection of increased positive edge rakes and clearances while also the use of edge shearing angles for enhanced mechanical removal efficiency. The elastic recovery of the elastomers is substantially reduced by the gradual and efficient penetration into the work piece of the edges 10 while the edges 10 also shear away cuttings transversely.
The most efficient machining of soft durometer, coverings or non-metals, such as rubber covered rollers, require that the edge rake and clearance angle along with the shearing angle be substantially increased. The increased deformation recovery of these materials make it necessary to increase the selectable positive cutting edge rakes, the edge clearance angles and the edge shearing angles to the axis of rotation of the tool. Increasing one or more of these angles is necessary to eliminate or substantially reduce the inherent friction and deformation of these materials that are easily deformed.
As shown in
These preformed edges 10, which are arranged on transfer tapes, allow for the edges 10 to be mounted at any of a predetermined selected shearing angle 26 to the axis of rotation of the tool 12. The shearing or mounting angle 26 generally is within the approximate range of zero degrees to 90 degrees to the axis of rotation of the tool 12.
The present invention has been described in an illustrative manner. It is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation.
Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described.
