US2013257A

US2013257A - Expansible drill

Info

Publication number: US2013257A
Application number: US5451A
Authority: US
Inventors: Vanderlick Stanley
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-02-07
Filing date: 1935-02-07
Publication date: 1935-09-03
Anticipated expiration: 1952-09-03

Description

Sept. 3, 1935. s VANDERUCK 2,013,257

EXPANS IBLE DRILL Filed Feb. '7, 1935 2 Sheets-Sheet l A9 i 6 Z a. /5 g V j 4 7 U I nventm- Sept. 3, 1935. s. VANDERLICK 2,013,257

I EXPANSIBLE DRILL Filed Feb. 7, 1935 2 Sheets-Sheet 2 T 6. Inventor Z17 5fanl z lizdfrlz'alk Patented Sept. 3, 1935 EXPANSIBLE DRILL Stanley Vanderlick, Nanticoke, Pa.

Application February 7, 1935,.Serial. No. 5,451

3 Claims.

a drill of the character above mentioned espeoially adapted for enlarging the bore of a previously drilled hole, to provide at the inner end of the bore a space for an explosive, as is done in;

for example, coal mining operations.

A further object of the invention is to provide a drill of this character which is characterized by extreme simplicity and economy in construction and number of parts.

The invention together with its objects and advantages will be best understood from a study of the following description taken in connection with the accompanying drawings wherein:

Figure 1 is a view illustrating a bore completed with my improved drill.

Figure 2 is a detail .elevational view illustrating the application of the invention.

Figure 3 is a detail sectional view of the expansible drill.

Figure 4 is an elevational view of a rod forming part of the invention.

Figure 5 is a perspective view of a blade.

Figure 6 is a sectional view taken substantially on the line 6-6 of Figure 5.

Figure 7 is an end elevational view of a tubular member.

Figure 8 is an elevational view of a collar.

Figure 9 is an end elevational view of a collar.

Figure 10 is an elevational view of a pilot bit.

My improved expansible bit comprises a body bar I having at one end a longitudinal slot 2. Secured tothe bar I by a pin 3 or in any other suitable manner, at the end of the bar remote from the slot 2 is a collar 4. The collar 4 is provided with notches 5 in which are pivoted as at 6 one end of blades 7. These blades are substantially wedge shaped in cross section as shown in Figure 6 and their free ends are curved outwardly as at la.

A tubular member 8 slidably receives the slotted end 2 of the bar I and is provided at one end with a pin 9 that operates in the slot 2. At the pin equipped end thereof the sleeve 8 is provided with a collar Iil that is provided in its outer edge with dove-tail slots II that receive the blades I which latter are as previously referred to, substantially dove-tail in cross section.

The sleeve 8 is adapted to receive therein the shank I2a of a conventional pilot bit I Z, the shank being secured in the sleeve 8 through the medium of a cotter pin or the like I3.

In actual practice, a bore I8 of the proper length and diameter is first drilled with the usual drilling apparatus. Such apparatus usually includes, in addition to the usual drill head, a supporting post I4 driven into the ground as shown. On the upper end of the supporting post is a threaded sleeve I5 on which is threaded a rod l6 equipped at one end with a handle I'I. At its opposite end the rod or screw I6 is provided to accommodate the usual drill bit, (not shown) 0 After the bore I8 has been drilled, the usual bit is removed and my improved expansible bit is substituted therefor. In substituting my bit the free end of the shank I is secured within one end of a connecting bar or sleeve I9 which sleeve 15 is square in cross section, and the free end of the shank or bar I is provided with a recess Ia to receive the spring pressed locking ball or other element with which the end of the connecting sleeve I9 is equipped. The sleeve I9 is connected 20 at its other end to the squared non-threaded end of the rod I6 in substantially the same manner.

With my improved bit assembly thus connected to the rod I6, the rod is rotated for moving the assembly lengthwise of the bore I8 to the inner 25 end of the bore when the pilot bit I2 begins its drilling operation followed by the expansible bit carrying the blades I'I. During this drilling operation, the shank I moves inwardly of the sleeve 8 against the action of a coil spring 20 disposed 30 about the shank I between the collars 4 and I0 as shown in Figure 3, with the result that my expansible bit expands, that is to say, the arms or blades "I are caused to move radially outwardly with the result that a substantially conical bore I8a first results and after the widest end of the bore I8a is made further drilling operation will result in the provision of an extension bore IBb of substantially the same diameter as the widest or largest diameter of the tapered bore I 8a. Thus with this expansible bit an enlarged bore or pocket is provided at the inner end of the usual bore l8, and into this pocket formed by the bores I8a and I8b the explosive is packed.

It has been found in actual practice, that better results are obtained by the provision of bores such as the connecting bores I8a and lb for receiving the powder than where the powder is packed into a bore similar to bore I8 and of uniform diameter throughout its entire length.

Among the advantages of the invention are: better grade of coal-elimination of pot-holes by confining explosives into pocket; greatly reduce explosive expenses; saving of time and labor, (reducing numbers of holes) and; elimination of fire hazards as now from unexploded powder left in burning holes.

Having thus described the invention, what is claimed as new is:

1. An expansible drill bit including a shank, a sleeve slidably receiving the shank, a collar on one end of the sleeve, a collar on the shank, blades pivoted at one end to the collar on the shank, and the collar on the sleeve being provided with mortise notches, and said blades being of a cross sectional shape corresponding to said notches and engaging in said notches, and a spring disposed about said shank between said collars.

2. An expansible drill bit including a shank, a sleeve slidably receiving the shank, a collar on one end of the sleeve, a collar on the shank,

blades pivoted at one end to the collar on the shank, the collar on the sleeve being provided with mortise notches, said blades being of a cross sectional shape corresponding to said notches and engaging in said notches, a spring disposed about said shank between said collars, and a pilot bit having a shank secured within said sleeve.

3. An expansible drill bit including a shank, a sleeve slidably receiving the shank, a collar on one end of the sleeve, a collar on the shank, blades pivoted at one end to the collar on the shank, the collar on the sleeve being provided with mortise notches, said blades being of a cross sectional shape corresponding to said notches and engaging in said notches, a spring disposed about said shank between said collars, a pilot bit having a. shank secured within said sleeve, an operating screw, and means detachably connecting the free end of said shank with said screw.

STANLEY VANDERLICK.