Degradation picks are known to be used in such fields as road milling, mining and trenching to engage and degrade tough materials such as asphalt, concrete and rock. Such degradation picks may be secured to an exterior of a rotatable drum so as to be repeatedly brought into contact with a surface of a material to be degraded. Each degradation pick may comprise a hardened tip designed for repeated impact with a tough material. Such repeated impact may break up the tough material into aggregate pieces. To secure such degradation picks to a rotatable drum, a generally cylindrical shank opposite the hardened tip may be disposed within a bore within a block that is rigidly fixed to the drum.
It may be desirable to position additional degradation picks in strategic locations around a rotatable drum. For example, the ends of a rotatable drum when viewed along a rotational axis thereof may engage tough materials not only around a perimeter of the drum but also beyond the end of the drum. In such cases, it may be desirable to position additional degradation picks proximate the end of the drum to engage this additional material.
Additional degradation picks may be disposed proximate an end of a drum by attaching a ring to an end of a drum to hold additional degradation pick blocks. For example, U.S. Pat. No. 4,225,190 to Hoffmann describes a mining auger which is used in the underground mining of coal comprising an end ring along its outer periphery. A plurality of tool holders is provided along a free edge of the end ring. The longitudinal axis of each tool holder coincides with the longitudinal axis of each cutting tool bit arranged in the respective tool holder.
By way of another example, U.S. Pat. No. 4,411,475 to Best et al. describes a cutting drum for an extracting machine assembled of a base body having a frustoconical configuration and an end ring which is detachably mounted to a major end face of the base body. The end ring is provided along its periphery with a plurality of tool holders for accommodating picks.
Despite these advancements in the art, the need for even tighter formations of degradation picks than those possible by arranging tool holders around the periphery of an end ring is still desirable. This is because each of the tool holders occupies a given footprint thus limiting the number that may fit in any defined area.
A degradation pick support may comprise a toroidal body comprising an interior surface and an exterior surface. The interior surface may be rigidly attachable to a rotatable body. The exterior surface may comprise a plurality of bore holes disposed there around. A plurality of degradation picks may be secured within the bore holes.
The toroidal body may be secured to a rotatable body that may be generally cylindrical, conical or frustoconical in shape. The toroidal body may be coaxial with the rotatable body and be secured proximate an end of the rotatable body along a rotational axis thereof A portion of the exterior surface facing the rotatable body may be substantially planar while another portion of the exterior surface facing opposite the rotatable body may be substantially curved.
The plurality of bore holes may be disposed around the toroidal body in a helical pattern. Further, in various embodiments, the rotatable body may comprise a generally helical flange disposed around an exterior thereof wherein the flange may be substantially the same height off of the rotatable body as the toroidal body in a direction normal to an exterior of the rotatable body. The plurality of bore holes may be disposed in a pattern continuing from the helical flange.
At least one of the bore holes may comprise an interior surface material tougher than a remainder of the toroidal body. In various embodiments, replaceable sleeves may be placed within the bore holes or the bore holes may each comprise a counter bore sufficiently large to encompass a degradation pick secured within the bore hole. Also, the toroidal body may be formed of a unitary mass.
Each of the plurality of degradation picks may comprise a hardened tip opposite a shank. Each shank may be disposed within an individual bore hole. When the toroidal body is secured to a rotatable body, a hardened tip of at least one of the plurality of degradation picks may extend beyond an end of the rotatable body along a rotational axis thereof In specific embodiments, several of the plurality of picks, evenly distributed among the plurality of picks, may comprise hardened tips extending beyond the end of the rotatable body along a rotational axis thereof The rotatable body may further comprise a plurality of blocks secured thereto with a plurality of degradation picks substantially similar to the plurality of degradation picks secured within the bore holes secured within the blocks.
A plurality of degradation picks 120 may be secured to an exterior of the rotatable drum 110. As the rotatable drum 110 is rotated the degradation picks 120 may be repeatedly brought into contact with a surface of a material 130 to be degraded. Such repeated impact may break up the material 130 into aggregate pieces 132 that may be removed by a conveyor 134.
In various embodiments, the helical flange 212 may be substantially the same height off of the rotatable drum 210 as the toroidal shaped support 240 in a direction normal to an exterior of the rotatable drum 210. Further, the helical pattern of the bore holes around the toroidal shaped support 240 may continue from that of the helical flange 212. It is believed that such a helical pattern may aid in channeling aggregate pieces of material away from the degradation picks 220 point of impact.
In various embodiments, some of the degradation picks 220 secured to the toroidal shaped support 240 may extend beyond the end 214 of the rotatable drum 210 along a rotational axis thereof. In the embodiment shown in
Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention.
This patent application claims priority to U.S. Provisional Pat. App. No. 62/029,370 entitled “End Ring for a Degradation Drum” and filed Jul. 25, 2014, which is incorporated herein by reference for all that it contains.
Number | Date | Country | |
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62029370 | Jul 2014 | US |