US2314348A

US2314348A - Abrading tool

Info

Publication number: US2314348A
Application number: US427929A
Authority: US
Inventors: John C Garand
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-01-23
Filing date: 1942-01-23
Publication date: 1943-03-23
Anticipated expiration: 1960-03-23

Description

March 23, 1943. J. c. GARAN D ABRADING TOOL Filed Jan. 23, 1942 ZAShe'ets-Sheet 1 a] John llllafand March 23, 1943. J, c, GARAND ABRADING TOOL Filed Jan. 23, 1942 2 Sheets-Sheet 2 gnuw m :lmhn ll B arand j/W time/ 4 sa /21W Patented Mar. 23, 1943 UNITEDSTATES PATENT OFFICE ABRADING TOOL John C. Garand, Springfield, Mass. Application January 23, 1942, Serial No. 427,929

(Cl. 51-1841) (Granted under the act of March 3, 1883, as

6 Claims.

amended member of an abrading machine tool in engage ment with the work. Another object is to provide an abrading tool whereby the abrasive member is held in engagement with the work by either spring or fluid forces or by a combination of both forces.

Another object of my invention is to provide an abrading tool whereby the abrasive is held in engagement with the work by spring force, which force is supplemented by a fluid pressure force, which fluid is then utilized for efficient and effective lubrication of the abrading surfaces.

A further object of my invention is to provide a power-driven abrading tool particularly adapted for abrading interior surfaces. A device embodying my invention will further permit the effective abraoling of interior cylindrical surfaces by either a longitudinal motion of the abrasive member, or by a rotary motion, or by any combination of longitudinal and rotary motion.

A particular object of my invention is to provide an abrasive supporting fixture adapted to be driven by power mechanism for abrading the interior cylindrical surface of the chamber of a firearm, whereby the abrasive member is held in work engaging position through the combined forces of a spring and a fluid pressure, which fluid is also utilized to lubricate the work and abrading surfaces. In performing abrading operations, or more particularly, honing operations, upon the interior surface of the chamber of the firearm, it is essential that the abrasions produced on such surface are longitudinal to permit the ready extraction of a cartridge from such chamber after firing of the cartridge. A device embodying the features of my invention permits such a longitudinal honing operation to be readily accomplished.

ihe specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

, Fig. 1 is an external view of an assembled April 30, 1928; 370 O. G. 757) abrading fixture constructed in accordance with my invention;

Fig. 2 is a longitudinal sectional view of theassembly in Fig. 1 taken on the line 2-4;

Fig. 3 is a cross-sectional on the line 33;

Fig. 4 is a cross-sectional view of Fig. 2 taken on the line 4-4;

Fig. 5 is a perspective view of the abrasive member assembled to the holding member;

Fig. 6 is a perspective view of the fluid guide;

Fig. 7 is a broken view in longitudinal section of the forward portion of the abrading fixture in position for use in a barrel chamber; and

Fig. 8 is a cross-sectional view of the assembly in Fig. '7 taken on the line 8'-8.

Referring to the drawings wherein like numerals in each view refer to similar parts, one embodiment of my improved abrading tool comprises a long, generally cylindrical, abrasive supporting member I having at one end thereof a portion 2 of slightly reduced diameter and a shank 2a for engagement by the tool engaging member of a driving apparatus. The driving apparatus for the abrasive supporting member I has not been shown but it should be understood that it may be of any conventional type which will engage the abrasive supporting member I and, drive it with any desired longitudinal or rotary motion or combination thereof. On the other end of the abrasive supporting member I there is provided a reduced diameter extension 3 having a tapered nose which performs a function to be explained later. The abrasive supporting member I is provided in its central portion with one or more longitudinal slots 4 which extend into extension 3. Each of these slots will support an abrasive member in a manner to be explained and, hence, it is apparent that any desired number of such slots may be provided depending only upon the desired diameter of supporting member I and the width of the abrasive members which it may be desired to use. In my preferred embodiment I provide two such slots 4 which are diametrically opposite and are best shown in cross-section in Figs. 3 and 4. Each slot 4 is of appreciable depth with respect to the radius of supporting member I and defines side walls 5 and base 6. Hereinafter the description will proceed with respect to only one of such slots 4 but it should be understood that the other slot 4 and its cooperating members will be identical to the structure described. v

The supporting member I is longitudinally drilled through its end 2 to provide a fluid supply view of Fig. 2 taken I passage 1 which communicates between a source of fluid within the driving apparatus (not shown) and the end of slot 4 by way of the small fluid entrance chamber 9. The entrance chamber 9 is conveniently formed by drilling through the base 6 of slot 4. The slot 4 is preferably provided with a semi-circular end portion I2 substantially tangent to the entrance chamber 9. The other end wall of slots 4 isgiven a rectangular shape by means of inserts 3a which fill the slotted portions of extension 3 and are secured therein bymeans of the pin 3b.

Adjacent to the center portions of slot 4-there is provided on each side wall 5, a lip Iiloverhanging the slot 4. Likewise at the end of slot 4, adjacent to the reduced diameter portion 3,

overhanging lips II are provided (Fig. 4)

A fluid guide I3 (Fig. 6) is provided of suitable shape and dimension to permit it to fit in the slot 4. One end I5 of the fluid guide I3 is semicircular to engage the correspondingly shaped end I2 of slot 4. The other end of fluid. guide l3 is provided with'recessedportions- I6 which are adapted to engage the undersurface of center lips II] when fluid guide I3- is inserted in slot 4. The exterior surface of fluid guide I3 is preferably'of the same arcuate shape as thesu-pporting member I so that when fluid guide I3 is inserted in slot 4 the resulting assemblage is of substantially cylindrical cross-sectionas best shown in Figure 3. The interior su-rface'of fluid guide I3 is provided with a longitudinal slot I4 which serves as afluid passage. This fluid passage I4 at oneend overliesthe-fluid chamber 9 and at its otherend overlies a fluid dispersion chamber 8 which is formed by' cutting a slot through the base 6 of slot 4 in that portion adjacentthe center lips ID.

The abrasive member I8 is of a longitudinal rectangular shape havingone arcuate surface I8a ofsubstantially the-same radius as the surface of supporting member I (Fig. 4). The abrasive I8- is engaged throughout its length by a metallic holding member I9 which is generally U shape in cross-section and its exterior dimensions are such as to readily fit in the slot 4. The length of the arms ofthe U-is less thanthe clearance between the lips H3 or IIandthe base 6 of'slot 4. The widthof the abrasive member l 3 permits its passage between the lips ID or II. The U shaped holding member I9 is cemented or otherwise fastened around-thenon-arcuate sides-of the abrasive I8. Thus when the assemblage of holder I9 and abrasive I8is placed in slot 4 the arcuate surface of abrasive I8 will form a segment of a cylinder substantially coaxial with and of slightly larger diameter than the supporting member I. At each end of the holder I9 cut-away portions 23 are providedwhichengagewith lips I0 and Ii upon assemblage of the holder I9 within that portion ofslot 4 between lips I9 and II and allow for limited radial movement of the holder and abrasive. An-arcuate leaf spring 2| is provided for insertion between the holder I9 and the base 6 of slot 4; The end of spring 2| underlying center lip Ii] is engaged by a recess 24 provided on the abutting. end'of fluid guide I3.

In assembling. the Various elements in slot 4 the spring 2| is first inserted in the left hand. portion of slot 4 and then slid into the right hand portion of slot 4 andheld therein by the lips I6 and II-. The holder H] with the abrasive I8 is inserted in a similar manner in the left hand portion of slot 4 and is slid longitudinally of the slot into the right hand portion of the slot on top of spring 2|. The holder I9 is thus forced outwardly by spring 2| so that its cut away portions 20 yieldingly engage the lips I0 and I I. Then the fluid guide I3 is dropped into place and, as previously pointed out, the recess 24 engages the end of spring 2| limiting longitudinal movement thereof. At the same time the end of fluid guide I3 abuts against the end of holder I9, preventing longitudinal movement of the holder I9 and hence, of the abrasive I8.

The fluid guide I3 is held securely in place by set screws 23 mounted in a collar 22 which surrounds supporting member I. The collar 22 is provided with an interior ridge 25 which engages the shoulder 2b formed by the transition of diameter between portion 2 and the main portion of supporting member I. Since the set screw 23 engages the depression I! (Fig. 2) in fluid guide member I3, the fluid guide member I3 is securely locked against any type of movement, and hence the abrasive member I8 cannot be disengaged from the supporting member I. It will be apparent from the foregoing description that the tool may be quickly disassembled and a worn abrasive member replaced.

In operation, the assemblage carrying the abrasive members I8 is inserted within the interior surface of the work piece. The spring 2I operates-to force the abrasive member outward into engagement with the work surface. The force of the spring is supplemented by fluid pressure which fluid is supplied through passage 1, entrance chamber 9. longitudinal slots I4 and dispersion chamber 8. After entering chamber 8-the fluid fills the space between base 6 of slot 4, and the base of holder I9, exerting an additonal outward force pressing the abrasive I8 into engagement with the work surface. The provision of the chamber 8 insures equalization of the fluid pressures applied to each of the abrading members. This additional fluid force is of course adaptable to regulation through a substantial range by variation of the pressure at which the fluid is supplied. At the same time the fluid is forced through the clearances between the sides of holder I9 and the sides 5 of slot 4 and is thus supplied to lubricate the working surface of abrasive I8 and the work surface. It is apparent that such an abrading tool may be readily operated with a rotary or longitudinal motion or any combination thereof.

The reduced diameter extension 3 of supporting member I performs an important function when a device embodying my invention is utilized in the longitudinal honing of the interior surface of the chamber of a firearm as shown in Fig. 7 It has been found convenient to perform such honing operations with the barrel 21 of the firearm in a vertical position with the chamber 28 at the bottom. If the extension member 3 is not provided, it is found that the close coaction of the surfaces of the tool and the chamber surface would produce a piston-like effect upon the lubricating fluid. A pumping action would result and the lubricating fluid would gradually be pumped up through the barrel. The provision of the extension 3 on supporting member I prevents such pumping action by entering the reduced diameter portion 28a of the chamber 28 on each upstroke of the abrasive supporting member I. The diameter of extension 3 is such as to produce only a small clearance between it and walls of chamber portion 28a as shown in Fig. 8. Hence in effect a sealing action is produced between extension 3 and chamber portion 2&1 preventing a substantial amount of fluid from being pumped upward into the barrel. The fluid of course is drained from the chamber by gravity and is collected for recirculation by conventional means.

The construction disclosed has the further advantage that, if desired, the abrading tool may be operated without the use of the lubricating fluid, using only a suitable spring 2| to force the abrasive member l8 against the working surface. Conversely the spring 2| may be omitted and the operating force produced entirely by the pressure of the lubricating fluid.

I claim:

1. A tool for abrading interior surfaces comprising in combination, a supporting member adapted to be inserted in the work to be treated, longitudinal slots in said supporting member, fluid guide members inserted in part of each of said slots and detachably secured therein, abrading elements inserted in the remaining part of each of the slots and secured therein by the abutting fluid guide member, resilient means forcing the abrading element into work engaging relation with the work, a fluid passage connecting that base portion of each slot underlying the abrasive elements with the fluid guide member and means for supplying lubricating fluid to the fluid guide member.

2. A tool for abrading interior surfaces comprising in combination a supporting member adapted to be inserted in the work to be treated, longitudinal slots in said supporting member, fluid guide members inserted in part of each of said slots and detachably secured therein, abrading elements inserted in the remaining part of each of the slots and secured therein by the abutting fluid guide member, resilient means mounted between each of said abrading elements and the underlying base of its slot forcing the abrading element 'into engaging relation with the work, a'fluid'dispersion chamber connecting the underlying-, base portion of each slot with the fluid guide members, means for supplying lubricating fluid under pressure to the fluid guide members, said fluid pressure producing a Work engaging force on the abrading elements, and leakage means whereby said fluid lubricates the working surfaces of the abrading elements.

3. A tool for abrading interior surfaces comprising in combination, a supporting member adapted to be inserted in the work to be treated, longitudinal slots in said supporting member, fluid guide members inserted in part of each of said slots and detachably secured therein, abrading elements inserted in the remaining part of each of the slots and secured therein by the abutting fluid guide member, a fluid passage connecting that base portion of each slot underlying the abrasive elements with the fluid guide member and means for supplying lubricating fluid to the fluid guide member.

4'. A tool for abrading interior surfaces comprising in combination a supporting member adapted to be inserted in the work to be treated, longitudinal slots in said supporting member, fluid guide members inserted in part of each of said slots and detachably secured therein, abrading elements inserted in the remaining part of each of the slots and secured therein by the abutting fluid guide member, a fluid dispersion chamber connecting the underlying base portion oi each slot with the fluid guide members, means for supplying lubricating fluid under pressure to the fluid guide members, said fluid pressure producing a work engaging force on the abradin elements, and leakage means whereby said fluid lubricates the working surfaces of the abrading elements.

5. A tool for abrading interior surfaces comprising in combination, a supporting member adapted to be inserted in the work to be treated, longitudinal slots in said supporting member, fluid guide members in part of each of said slots, abrading elements in the remaining part of each of the slots, overhanging portions of said slot retaining the abrading elements in the slot at their ends and further overhanging portions of the slots retaining the other ends of the abrading elements and the adjacent ends of the fluid guide members in the slots, and removable means for holding the other ends of the fluid guide members in the slots.

6. A tool for abrading interior surfaces comprising in combination a supporting member adapted to be inserted in the work to be treated, longitudinal slots in said supporting member, fluid guide members in part of each of said slots, abrading elements in the remaining part of each of the slots, overhanging portions of said slot retaining the abrading elements in the slot at their ends and further overhanging portions of the slots retaining the other ends of the abrading elements and the adjacent ends of the fluid guide members in the slots, and removable means for holding the other ends of the fluid guide members in the slots, a fluid passage connecting that base portion of each slot underlying the abrasive elements with the fluid guide member and means for supplying lubricating fluid to the fluid guide member.

JOHN C. GARAND.