US2544444A

US2544444A - Bevel recessing reamer

Info

Publication number: US2544444A
Application number: US740892A
Authority: US
Inventors: Louis M Clark
Original assignee: Individual
Current assignee: Individual
Priority date: 1947-04-11
Filing date: 1947-04-11
Publication date: 1951-03-06
Anticipated expiration: 1968-03-06

Description

March 6, 1951 M, CLARK 2,544,444

BEVEL RECESSING REAMER Filed April '11, 1947 IN VEN TOR. [cu/5 M (Zap/r ATTOR/VE Y Patented Mar. 6, 1951 UNITED STATES PTENT OFFICE BEVEL RECESSING REAMER Louis M. Clark, Fort Collins, C010.

7 ApplicationApril .1 1, 1947,,Serial No. 740,892

This" invention relates bevel recessing reamers.

In'the manufacture of furniture and in wood "working manufacture generally, it is frequently necessary to' provide an article such as a' chair with-braces or bars and these are usually made turning down an end portion to a predeterjinined size, inserting this into a hole of the same size and securing the two parts together with a liberal quantity of glue.

As an example of an article that is frequently constructed in this manner, reference is made to the ordinary dining room chairs.

It is evident that a much better and more secure joint would be obtained between two members if the hole in one member were inwardly flaring and the male portion of the other member reduced to a size of the outer end of theopenmg; "split and provided with ,a wedge in such a 'way that when it is driven into the hole or opening the end will spread and conform tothe sides of theinwardly flaring hole.

It' is the object of this invention to produce a simple and substantial tool that can be usedv either in a drill press, or with an ordinary hand operated brace and which will quickly ream prebored holes so as to give them an increasing diameter inwardly towardsthe bottom.

Another object of this invention is to produce:

a device of the class mentioned which shall be of a simple construction and so designed that the cutter blades may be readily removed for sharpening. a

A further object of. the invention is to produce a tool of the type indicated in which no part of the tool will contact the outer surface of the member having the opening that is being reamed.

. -A- further object of the invention is to produce a tool of such construction that all holes reamed thereby will be exactly alike.

A further object of the invention is' to produce a tool with a few rugged-parts that can be easily assembled and whichcan be held from moving 'in' response to the torque forces exerted thereon I 2 Claims; (01. 145 114) to: improvements in Figure 2 is a section taken on line 2'-2, Figure 1; I

i Figure 3 is an enlarged fragmentary view .taken partly in section on line 2--2, Figure 1, and show ing other parts in elevation; "Figure 4 is a section taken on line 4-4, Figure 3;

Figure 5 is a section taken on line 55, Figure 3; and

Figure 6 is a section through a member showing an inwardly flaring opening in which is positioned the expanded end of a brace member.

Referring now to the drawing,v reference numeral l designates theelongated hollow body of the tool, and reference numeral ll designates the shank portion thereof, which may be of the proper size and shape to fit the means by which it'isrotated. Body I!) is provided with an axial opening l2 that terminates in ashort section of concentric opening whose wall has been designated by numeral 13. The end opening is of larger diameter than the main opening l2 and the outer end of the wall of the smaller or inner opening has a threaded section l4. Positioned within the open end of the tubular body is a plug l having an axial opening l6 and longitudinally extending grooves I! in its outer surface. In the drawing four such grooves have been shown. A smaller or larger number may be used, if desired. Plug l5 has a threaded section of the proper size to operatively engage the threads in the inner surface of tubular body In and an outer. cylindrical section of greater diameter than the threaded section. The outer enlarged end ,"of the plug is provided with transverse notches I8 at the inner ends of grooves l1. Wall l3 surrounds the outer grooved end of the plug and forms a closure for the grooves therein. Wall [3 has a threaded opening at each notch I! in which is positioned a screw l9 that serves as an abutment for spring l9, that serves to hold cutter blades in thecollapsed position shown in Figures-2 and 3 un'til they are urged outwardly by the spreader in a'manner hereinafter described. Cutter blades 2%! have a shape somewhat like that shown in Figures 2, 3 and 4 and are 7 positioned in grooves l1 as-shown. Set screws 19a prevent the plugifrom rotating (Fig. 5). The free ends of the blades are each provided with an inclined surface that forms a cutting edge 2i The inner ends of the cutter blades are provided with laterally projecting trunnions 22 that are located in notches l8 and prevent the cutting blades from.moving outwardly while permitting them to spread laterally to a limited extent.

A blade spreading member comprising a cam having an inwardly tapering frustoconical surface 23 and an axially extending cylindrical portion 24 is so positioned that member 24 projects through the opening H in plug l5 and terminates in a threaded end portion 25. A round nut 26 is connected with the threaded end portion as shown. A helical compression spring 21 is positioned in opening [2, one end abutting the inner end of opening 12 and the other end abutting the nut 26. Spring 2'! is under compression and tends to hold the parts in the position shown in Figure 2 in which position the outer surfaces of the cutting blades are substantially parallel. The maximum distance between the outer surfaces of diametrically positioned blades is slightly less than the diameter of the hole to be reamed. The largest diameter of the cam 23 is less than the diameter of the opening to be reamed and therefore the tool may be inserted into the opening with thebase' of part 23 resting on the bottom of the hole to be reamed. The tool is now rotated .in'such a direction that the side nearest the observer when viewed as in Figure 3, moves downwardly. This produces a cutting action on the part of the cutter blades, and as these move inwardly into the opening they are spread apart by the cam action of member 23 with the result that an inwardly flaring hole like that designated by'referencenumeral 28 in Figure 6 results. The length of the spreading cone or cam should be such that the distance from the cutting edges 21 to the base of the cone portion shall be equal to the depth of the hole to. be flared. This distance .has been designated by the letter (Z in Figure 2.

' After the hole has been reamed and flared to .the'shape shown in Figure 6, the end of bar 29, that is to be inserted therein, is split diametrical- .'ly and provided with a wedge 30. When the bar driven into the opening the wedge will be forced into the end-of the bar spreading it in the manner .shown in Figure 6. The. two parts will then be permanently and rigidly interconnected. If desired glue may be used in addition to the wedge,

in either case it wiil be'practically impossiblev to separate the parts due to the inwardly flaring interconnecting surfaces.

From the above description it will be seen that .by use of the tool described herein and shown on the drawing, holes bored by ordinary angers can be readily reamed into a shape in which they are inwardly flaring with the result that any joint constructed in the manner described will be permanent.

Having described the invention what is claimed as new is:

.having a diameter greater than the root diameter of the threads, a plug having a threaded portion engaged in the threaded section, and a portion of greater diameter, said portion of greater diameter having a plurality of longitudinally extending grooves, cutter blades positioned in the grooves the grooved portion of the plug being positioned in the enlarged outer end of the body, the wall of which serves to close the grooves and secure the cutter blades therein, means providing a pivotal connection between the blades and the plug adjacent the inner ends of the notches, whereby the blades are free to spread, the plug having an axial opening, an outwardly flaring spreader cone having an axial rod-like member extending through the opening in the plug, an enlarged head on the inner end of said rod limiting its outward movement, and a compression spring positioned in the axial opening of the body in abutting relation with the bottom of the opening and the enlarged head, the force of the spring normally holding the cone in its outermost position.

2. A bevel recessing reamer, comprising, in

combination, an elongated body having an axially extending shank at one end, the other end having an inwardly extending axial opening comprising two sections of different diameter, the one of larger diameter being adjacent said other end, the wall of the smaller opening having a threaded section extending inwardly from the juncture of said two sections, a plug comprising two sections of difierent diameters, the smaller section being threaded and in engagement with the threaded section of the opening wall, that portion of the plug of larger diameter being positioned in the enlarged outer end of the axial opening, the plug having an axial opening, the larger end of the plug having a plurality of longitudinally extending radial grooves terminating at their inner ends in transverse notches, a cutter blade positioned in each longitudinal groove, the inner ends of the blade having laterally extending trunnions engaging in the transverse notches for outward spreading pivotation, means latching the plug and tubular bodyagainst relative rotary movement, an outwardly flaring spreader cone having 'an axial rod-like extension extending through REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 599,655 Huben Feb. 22, 1898 762,458 Willard June 14, 1904 833,240 Potter Oct. 16, 1906 Seal Sept. 10, 1940