US 2575524 A
Description (OCR text may contain errors)
W. MnTcHr-:LL 2,575,524
ROTARY TOOL Nov. 20, 195] 2 SHEETS- SHEET l Filed OCC. 10, 1946 lNvENToR WALTER G. M |TCHELL ATTORNEY W. G. MlTCH ELL Nov. 20, 1951 y ROTARY TOOL 2 SHEETS-SHEET 2 Filed oct. 1o, 1946 INVEN'IOR WALTER G. MITCHELL 1M/CM ATTO RN EY.
Patented Nov. 20, 1951 UNITED! STATES PATENT OFFICE ROTARY TOOL Walter' G; Mitchell, Aurora, Ill., assignorto Inde-I pendent Pneumatic Tool Company, Chicago, Ill., a corporation ofl Delaware.
Applcation'October 10, 1946,` Serial N. 702,399
This `invention relates` to'improvements'inV uid operate it from' aisleevezwhich-ismounted on and shiftable relatively to the cylinder bushing of' the" tool motor* for 'changing the: direction ofthe" toolzmotor', vthe sleeve .andthe bushingl having a complement of exhaust' portsf. to. be'lbrought.. intoA andout of` register' in the .shifting of theasleeve.
A .further'i objectk ofV myl invention; is4 to have: the inlet passages for the tool fmotorzinthe. cylina derrbushingand opening throughzthezendl.of.;,the same at said meansso thatithe supply'of` iiiiid;
pressuref to' the` tool. motor for,- operatingv it .may be-:furnished fromA one end: of thel tool. device;
A-further object of my invention isto providel thefhandlexonthev sleeve in the forml of a knob orV other member extending throughaslotin the outer/casing of the tool for accessibility,Y from a position intermediate the -ends of the tool device. A-.further object off-.my inventionis to provide thefmeans rst mentioned inthe formof` afvalve connected with and operated by the sleeveon turning or shiftingdt by. said handle member.
A further object. of my invention is to provide said valve in the. form.of.a port. providedplate revolublyI mounted. on. one -of the Y end.. plates of thetool motor.
The. invention'` consists further in. the l struc-v turalieatures and. combination of parts. herein-- after.. described and. claimed.
Inthe accompanying drawings-m Fig. 1 is a longitudinal sectional .view` withi parts: in `elevation of the connectedmotor and throttle.Y valve sections' of ay portable pneumatically opere--V ated :rotary tool; embodying, the features: of: my invention, lthe section beingtaken approximately; online I-I of Fg:.2f'=with1the motor. in a.-.position;
2. with a pairl of'it's blades in theV planev of the section;
Fig. 2 is aV transverse sectional view taken on line'2-2" of: Fig. 1 showing the reversing sleeve of the motor unit shifted to a position for.v rotating the motor in one direction;
Fig' 3` is a similar sectional view shovvingthel reversingsleeve shifted rinto a'position for rotating the motor in theopposite or reverse direction;
Fig. 4 is a side elevational view of theA sleeve and bushing'fassembly` removed Vfrom thertool yfor theY purpose ofV illustration;
Fig; 5 is: atransverset sectional Vview taken .on line155 of Fig; 4to show the intertting'engager. ment of Vthelugsron `the sleevei withA the recessesN initheirvalve plate tobeihereinafter described;
Fig.' 6 is'a' top planview oftheassemblyshown' in Figi 4`;
Fig. '7 is a fragmentary sectional View taken-on line T-'I of Fig. 6to illustrate 'the porting system for admittingii'uidlpressuretov the tool motor;
Fig. 8 is aVv transverse sectional View" taken on lineS- ofFig.V l to show the: handle member secured to the reversing sleeve for shifting it; and
Fig. 9 isa' frontlview of the-toolat said handle member.
In the drawings, I indicates the outer casing'of the tool, the latter'bengv ofthe portable', hand held, pneumatically operatedvr rotary type having a work driving spindle' (notsliown) atits frontor outer'v end andV av manually depressible throttle valve 2 at'or adjacent itsrearor innenend as shown in Fig; l. The throttle'valve 2 controls the supply AofV iiuid pressure or compressed air to the tool motor for rotating it, and, hence, the starting and stopping of the tool is controlled. Said valve 2`is mounted in thetool caser l at the fluid pressure inlet passage 3' to' which an air supply hose (not shown) is connectedlas in tools of the character shown.
The valve' 2 is spring biased towards closed position and is movable towards unseated or open position by an' actuating lever 4 pivoted on the tool caseand extending over the outer end of the valve stem 5 to engage it. The lever l is arranged to extend'alongthe motor` section Gpf'the tool to be conveniently operated by the hand of the.
operator grasping and holding the tool about itsOuter casing.' lat the motor section 6.
Arranged with' theY motor section. E is a cylinder bushing clamped between the end plates 8; t:
ofithe'imotorunitand held against.rotation by a dowel pin or. key Idextendings through thebushing andtting' atitsendsinapertures. onrecessesfr in the respective end plates 8,. 9 as shown in Fig. 1. The pressure exerted by the casing sections in clamping them together holds the bushing 1 and its end plates 8, 9 in non-rotative relation and provides a rotor chamber II for a rotor I2 to be next referred to.
Eccentrically mounted within the chamber II is a rotor I2 which divides the rotor chamber II into two sections to provide the high and the low pressure chambers, respectively, for the motor as in devices of this character.
'I'he shaft extensions I3, 13a at the opposite ends of the rotor I 2 are mounted in anti-friction bearings I 4, I5 supported by the end plates 8, 9 for journalling the rotor I2 for rotation in the bushing 1. The lower shaft extension I3a has a splined connection at I 2a with the tool mechanism to be driven by the tool motor. In the tool illustrated, this mechanism comprises an impact clutch unit for driving and setting nuts and bolts by the power of the tool. In this connection, I may point out that the tool spindle which is at the front or outer end of the tool casing l has a nut or bolt head engaging socket (not shown) as in impact wrenches of the character mentioned.
The rotor I2 is equipped with blades I6, i6 slidably mounted in radial slots I1 in the rotor. The blades work against the inner cylindrical surface of the bushing 1 as in motor devices of the kind shown.
Mounted on and surrounding the bushing 1 is sleeve I8 for controlling the direction of rotation of the rotor I2 in accordance with my invention. The sleeve I 8 is located between the end plates, 8, 9 and has a ground and revoluble fit therewith and similarly with the outer cylindrical surface of the bushing 1 to avoid air leakage therebetween in the operation of the tool. This is indicated in Figs. l, 2 and 3.
The sleeve I8 has two sets of ports I 9, 20 arranged in groups, one on each side of the line of minimum clearance of the bushing 1 with the rotor I2 as shown in Figs. 2 and 3. The ports of each group are arranged in parallel, circumferentlally, spaced rows extending axially of the sleeve IB with the ports spaced apart in each row to serve the effective length of the motor unit as shown in Fig. 4.
The bushing 1 is provided with a like arrangement of exhaust ports 2i, 22. The ports 2| comprise the group employed in association with the ports I9, while the ports 22 comprise the group employed in association with the ports 29. The ports I9, 2!) in the sleeve IB extend therethrough and connect at their outer ends with an exhaust chamber 23 provided by the outer casing l entirely about the outer cylindrical side of the sleeve I8 as shown in Figs. l to 3. The outer casing I of the tool has a series or group of exhaust passages 24 leading from said chamber 23 to the atmosphere exterior of the tool.
The bushing 1 is provided with a pair of longitudinally extending passages 25, 26 located on opposite sides of, but relatively close to, the line of minimum clearance of the rotor I2 with the bushing 1 as shown in Figs. 2 and 3. These passages 25, 26 serve to selectively supply fluid pressure to the opposite sides of the rotor to rotate it in reverse directions. 'Ihe passage 25 is used to rotate the rotor I2 to the right or in a clockwise direction as indicated by the arrow ain Fig. 2, while the passage 26 is used to rotate the rotor I2 to the left or in a counter-clockwise direction as indicated by the arrow b in Fig. 3. This change of direction of rotation of the rotor I2 is under the control of the sleeve I 8 as will hereinafter more fully appear.
The bushing 1 is provided in its inner cylindrical surface with a number of circumferentially extending slots 21, 28, the iirst being associated with the passages 25 and the second being associated with the passages 26 as indicated in Figs. 2 and 3. The slots 21, 28 are in the plane of their respective ports 2l, 22 and intersect them as indicated in Figs. 2, 3 and '7. By this arrangement the slots 21, 28 in their respective sets convey live air from adjacent the point of minimum clearance of the rotor I2 with the bushing 1 to approximately the bushing port farthest removed therefrom, circumferentially of the bushing. Hence, iluid pressure is supplied to the bushing from an inlet passage 25 or 26 to the fullest extent of the circumferential area of the bushing occupied by the respective group of ports 2|, 22, respectively. Moreover, the porting system enables the blades to be under eiective fluid pres- Sure for more than degrees in either direction from the pin or key I9 as shown in Figs. 2 and 3. This increases the power and effectiveness of the motor unit as compared with previous designs.
When the sleeve I8 is turned to the position shown in Fig. 2, the ports I9 in the sleeve are moved out of register with the ports 2I in the bushing 1, while the ports 20 in the sleeve are brought into register with the ports 22 in the bushing 1. This closes the bushing ports 2I to the exhaust chamber 23 and fluid pressure is admitted into the bushing 1 through the passage 25 to act on the blades I6 to rotate the rotor I2 in the clockwise direction of the arrow a in Fig. 2. The exhaust at this time will be from the rotor chamber II through the registering ports 20, 22 on the now low pressure side of the rotor chamber as shown in Fig. 2.
Shifting the sleeve I8 into the position shown in Fig. 3 registers the ports I9 and 2I of the sleeve I8 and the bushing 1 for an exhaust from the now low pressure side of the motor unit, while the ports 22 in the bushing are now closed with respect to the ports 20 in the sleeve and the rotation of the rotor I2 is in the counter-clockwise direction of the arrow b as shown in Fig. 3.
To limit the extent to which the sleeve may be rotated, I provide the sleeve with a pair of diametrically disposed, depending lugs 29, 29 integral or otherwise iixed to the sleeve and extending into similarly disposed arcuate notches or recesses 30, 3i) in the peripheral edges of the lower end plate 9 which is fixed against rotation within the tool assembly as hereinbefore mentioned. The lugs 29 are at the outer periphery of the sleeve I8 and to one of them is secured a handle member 3l which works in an arcuate guide slot 32 in the outer casing I of the tool as detailed in Fig. 8. This handle member 3| is accessible from the outside of the tool casing and is actuated to rotate or shift the sleeve to control direction of rotation of the rotor I2.
The fluid pressure, in accordance with my invention, is supplied to a chamber 33 in the tool casing I at the upper end thereof, namely, about the upper shaft extension I3, when the throttle valve 2 is opened. Mounted on the hub portion 34 of the upper plate 8 is a turnable valve plate 35 which as shown in Figs. 6 and '1 is provided with a pair of ports 36, 31 to be brought alternately into and out of register with the inlet passages 25, 26 in the bushing 1 through matching ports 38, 39 in the interposed end plate 8 as shown in Fig. 7. The plate 35 seats on the agement;
end plate Viffand-'lis'.engaged;byaspaiiicf diametrically; disposed lugs 40, 40fextending upwardly the sleeve I8 are connected-atogether for rotationt` irmmison.. Thelength of the-recesses 30, lfldetermin'esgthec extent to. whichf theasieevezmayr be turned, the end walls of at least one of said recesses serving as stops forsuch purpose.
When the plate 35 is turned to the position shown in Fig. 7, the port 36 in the plate 35 is brought into register with the inlet passage 26 in the bushing 1 and live air is supplied to the tool motor to rotate it in one direction (arrow b in Fig. 3). The other port 31 in the plate 35 is at this time out of register with the passage 25. Turning the plate 35 in the opposite direction shifts the port 31 into register with the passage 25 and the tool motor is rotated in the reverse direction (arrow a in Fig. 2).
It will be noted from Fig. 1, that the passages 25, 2B open through the upper end of the bushing 1 and the supply of fluid pressure to the tool motor is from the chamber 33 which is in direct communication with the plate ports 36, 31. This contributes to the compactness of the tool and reduces its outside diameter for convenience in grasping and holding about the motor section 6 as heretofore mentioned. In brief, with the arrangement shown, the valve mechanism which is controlled by the sleeve I8 does not hinder the location of the throttle valve 2 at the rear end of the tool.
Moreover, with the sleeve I8 revolubly mounted in the tool casing about the bushing 1 the handle member 3| may be located at the side of the tool and extend out of the tool case intermediate its ends to free the upper or inner end of the tool for the control valves as herein shown. This contributes to the compactness of the tool device for ease of handling and manipulation of the tool as is apparent.
As detailed in Figs. 8 and 9, the slot 32 extends beyond the ends of the companion slot 30 and the handle member 3l is constructed to fully cover the inner slot 30 in all positions of handle member.
The details of construction and arrangement of parts shown and described may be variously changed and modified Without departing from the spirit and scope of my invention, except as pointed out in the annexed claims.
I claim as my invention:
l. In a fluid actuated rotary tool, an outer casing, a cylinder bushing non-rotatably mounted in said outer casing and providing a rotor chamber, a rotor eccentrically mounted in said chamber, a pair of longitudinally extending inlet passages in the bushing and connected with said chamber on opposite sides of the rotor for selectively supplying fluid pressure to the opposite sides of the chamber for rotating the rotor in opposite directions, a sleeve disposed between said casing and said bushing and fitting about said bushing and shiftable relatively thereto and relatively to the casing, said sleeve and said bushing having exhaust ports therein to be selectively brought into and out of register in the shifting of the sleeve to control the direction of rotation of the rotor, means for shifting the sleeve, an end plate at one end of said bushing having a pair of inlet passages in register lwith the inlet pasmounted on saidf-'endi plate' yand; i connected-"- to"l a sourceT4 of `:fliiif pressure and havingf'inlet ports;
adapted to alternately register witlrsaid-`feIId"-plateL inlet'- passageslto supply* iluid pressure to said rotor chamberthroughsaid end plate and said bushing.
2l In .at-fluid actuatedtrotaryftool;..an:outercasing, a cylinder bushing and endiplatesitherefor.' non-rotatably mounted in said outer casing and providing a rotor chamber, a rotor eccentrically mounted in said chamber, a pair of longitudinally extending inlet passages in said bushing and connected with said chamber on opposite sides of the rotor for selectively supplying uid pressure to the opposite sides of the chamber for rotating the rotor in opposite directions, a pair of inlet passages in one of said end plates in alignment with the inlet passages of the bushing, a sleeve revolubly fitted about said bushing, said sleeve and said bushing having exhaust ports therein to be selectively brought into and out of register in the rotation of the sleeve to control the direction of rotation of the rotor, a valve plate revolubly mounted on said one end plate and connected with the sleeve for rotation therewith, said valve plate having ports to alternately register with said inlet passages of the end plate to control the supply of fluid pressure thereto in the shifted positions of the sleeve, and means for rotating the sleeve.
3. In a fluid actuated rotary tool, an outer casing, a cylinder bushing and end plates therefor non-rotatably mounted in said outer casing and providing a rotor chamber, a rotor eccentricaly mounted in said chamber, a pair of longitudinally extending inlet passages in the bushing and connected with said chamber on opposite sides of the rotor for selectively supplying uid pressure to the opposite sides of the chamber for rotating the rotor in opposite directions, a pair of inlet passages in one of said end plates in register with the inlet passages of the bushing, a sleeve revolubly tted about said bushing, said sleeve and said bushing having exhaust ports therein to be selectively brought into and out of register in the rotation of the sleeve to control the direction of rotation of the rotor, a valve plate rotatably mounted on said one end plate and having ports to alternately register with said inlet passages of the end plate to control the supply of fluid pressure thereto in the shifted positions of the sleeve, lugs on the sleeve interconnecting the valve plate with the sleeve for rotation therewith, the interposed end plate having slots to receive said lugs, and means for rotating the sleeve.
4. In a fluid actuated rotary tool of the reversible type, the combination of a cylindrical bushing providing a rotor chamber, a rotor operatively mounted in said chamber, said bushing being provided with a pair of longitudinally extending inlet passages for admitting motive fluid at one end of said bushing and said bushing having circumferentially extending grooves at its inner surface for supplying motive fluid from said inlet passages to opposite sides of said chamber for rotating said rotor in opposite directions, inlet valve means comprising a shiftable valve plate at said one end of said bushing for regulating the admission of motive fluid to one or the other of said inlet passages, exhaust valve means comprising a shiftable valve sleeve surrounding said bushing, said bushing and said sleeve being provided with a plurality of exhaust ports adapted to be registered selectively by shifting of said sleeve to 2,575,524 7 control the direction of rotation of said rotor,V and means operatively connecting said sleeve and said Number plate whereby to permit simultaneous shifting 2257 892 movement thereof. 2,401,190 WALTER G'. MTCIIELL. 5 2:4141638 REFERENCES CITED The following references are of record in the Number file 0f this patent: l 387,287
UNITED STATES PATENTS Name Date Van Sittert Oct. 7, 1941 Reynolds May 28, 1946 Dobe Jan. 21, 1947 FOREIGN PATENTS Country Date Germany Dec. 27, 1923 France Nov. 6, 1936