Патент USA US2404048код для вставки
July 16, 1946- ‘ F. G. GEPFERT ’ DRILL Filed Aug. 5', 1944 ' 2,404,048 ‘ Patented July 16, ‘1946 2,404,048 UNITED STATES PATENT OFFICE I 2,404,045 a ‘ DRILL ‘ ' . Franklin G. Gepfert, Shaker Heights, Ohio Application August 5, 1944, Serial No. 548,150 2 Claims. (01.77-70) ' 1 2 This invention relates to drills, and particu larly to drills used for penetrating hardened met als. This particular invention is an improvement of the drill patented by Lester G. Black, on Octo ber 28, 1941, under Patent No. 2,260,288. The primary object of this invention is to pro and are equidistant from and parallel with each other. The body portion of the drill just below the shank portion In is slightly conical and in all other respects follows the standard Morse taper dimensions used for some of the prior art drills. The end portion of the drill speci?cally shown in the Figures 2, 3, 4 and 5 of the drawing has vide a drill of the type mentioned which more rapidly removes the chips or shavings from the three acute radially and longitudinally extending hole being drilled. It also enables the drill to be ridges I5 which extend from the longitudinal axis used for a longer period of time without resharp 10 or center ll! of the drill to the center of each of ening. the three ?llets l2. These ridges are formed by These and other objects of the invention will grinding three perfectly flat facets I4 thereon at an angle of forty degrees from the longitudinal become apparent from the following speci?cation“ and claims, together with the accompanying axis of the drill and form thereat three laterally drawing, wherein like parts are referred to and 15 extending ridges [9. The acute radially extend ing ridges l5 of the end portion are the only indicated by like reference characters and wherein: parts of this drill that make frictional contact Figure 1 is a view of the improved drill as it is with the work being perforated, and are at an angle of about sixty degrees from the longitudinal mounted in a collet chuck; Figure 2 is an enlarged elevational view of a 20 axis of the drill. This drill, unlike the drill portion of the body of the drill and the end shown in the Patent No. 2,260,288 which has per thereof as viewed from one angle; fectly straight ?at flutes and straight non-inclin Figure 3 is a view similar to that of Figure 2 but ing parallel ?llets, does not burnish or scrape the viewed from another angle; inside surface of the hole due to the upward taper Figure 4 is a view similar to that of Figures 2 25 of the instant body. ‘ and 3 but viewed from still another angle or di The chip clearance grooves I6 of the instant drill are somewhat/larger than the grooves of the rection; and earlier drill shown in the lPatent No. 2,260,288 and Figure 5 is a bottom end view of the drill. they make possible an easier passage of the chips Referring to the drawing, there is shown in the Figure l a drill having a shank portion l0 30 upward along the flutes I I. These grooves 16 are concave and consume the large central portions of which ?ts into a regular collet chuck 8 or other the facets l6 and thereby smoothly connect with holder. The Figure 1 also shows a cross section the adjacent flutes l I. of the work 9. It will now be clear that there is provided by The drill member consists of three integral parts which will be described separately. First, 35 this invention a drill for penetrating hardened metals and which accomplishes the objects set there is the round shank portion I0 that is more forth. While the invention is illustrated and de or less standard and which in itself possesses no scribed in a certain preferred form, it is obvious novel features, as far as this invention is con that there may be other forms or adaptations of cerned. Next, there is the body portion of the drill which is below the shank portion ID. The 40 the invention. For example, the drill body may body portion has three spiraliform ?utes I l and be made with four or more ?utes and ?llets in stead of with the three as shown. The drill body three helical ?llets I2 therebetween. The ?utes may also be made of untapered stock, if desired. II are ground out of the solid metal forming the The drill end for some purposes may be made body portion and‘are preferably substantially flat or straight across. However, they are very 45 straight or concave instead of being pointed as slightly concave in cross section, as is shown in shown. These modi?cations are also considered the Figure 5 due to the convexity of the grinding to be included in this invention, as no limitations upon it are intended other than those imposed wheel. The ?llets [2 are not sharp but are slightly convex. Peripheral lines on the convex thereon by the scope of the appended claims. surfaces of the ?llets 12 are parallel to the pe 50 I claim: rlpheral surface of the shank portion and have slightly smaller arcs, but are concentric there with, as is clearly shown in the Figure 5. The helixes or spirals formed by the ?llets are uni 1. A drill of the type described, comprising in combination, a round shank portion receivable by a holder, a body portion substantially trian gular in cross section integral with the shank form throughout the entire length of the body 56 portion and having spiraliiorm ?utes thereon £2,404,048 . 3 forming helical ?llets therebetween, the said ?utes having substantially ?at surfaces and the said ?llets having peripheral surfaces concentric with the said shank portion, and a pyramidal end portion integral with the body portion and hav 4 portion and having three or more spiraliform ?utes thereon forming three or more helical ?l lets therebetween, the said ?utes having substan tially ?at surfaces, and an end portion integral with the body portion and having three or more ing ?at facets thereon forming straight radially facets thereon forming three or more radially and longitudinally extending ridges therebe tween, each of the said facets abutting a ?ute and longitudinally extending ridges therebe tween, each of the said facets being at an angle of about forty degrees from the axis of the drill and forming thereat a lateral ridge, each of the said radially extending ridges abutting a ?llet 10 and abutting a ?ute and forming a lateral ridge and all of the same forming a sharp point at the thereat, each of the said radially extending ridges abutting a ?llet and all of the same form axis of the drill, the said body and end portions having a concave groove at each lateral ridge, ing a sharp point at the axis of thedrill, the said and each of the said grooves consuming a sub body and end portions having a concave groove stantially large portion of the facet thereat. 15 at each lateral ridge, and each of the said grooves 2. A drill of the type described, comprising in consuming a substantially large portion of the combination, a shank portion receivable by a facet thereat. holder, a body portion integral with the shank ' FRANKLIN G. GE-PFERT.