US3673921A - Pressurized fluid device - Google Patents

Abstract

A portable pneumatic tool including an elongated housing having a rotatable output member supported thereon and adapted to have a wrench socket attached thereto. Lever means within the housing is interconnected with the output member through one-way clutch means and is oscillated by compressed air whereby to impart unidirectional rotation to the output member. In addition, the tool may be used as a hand-type wrench in which case the elongated housing operates as a handle and the one-way clutch means causes the output member to turn conjointly with the housing in one direction only.

Description

O Unlted States Patent [151 3,673,921 Fritts et al. 1 July 4, 1972 [54] PRESSURIZED FLUID DEVICE FOREIGN PATENTS OR APPLICATIONS [72] Inventors: fil l A- ri g enix; Jerome 1. Re- 17,016 1890 Great Britain ..91/339 d, imonium,bo of Md.

7 Primary Examiner-Paul E. Maslousky [73] Asslgnee' 2: E E :11 6 Manuhcmring Attorney-Leonard Bloom, Joseph R. Slotnik and Edward D. p y, 9 [22] Filed: June 8, 1970 211 Appl. No.: 44,068 [57] ABSTRACT A ortable neumatic tool includin an elon ated housin h P at bl t b g d h g avmg a ro a e outpu mem er supporte t ereon an "g." adapted to have a wrench socket attached thereto. Lever [58] Fieid 91/359 299 325 means within the housing is interconnected with the output member through one-way clutch means and is oscillated by compressed air whereby to impart unidirectional rotation to [56] References cued the output member. In addition, the tool may be used as a UNITEDSTATES PATENTS hand-type wrench in which case the elongated housing operates as a handle and the one-way clutch means causes the l 1( g F f output member to turn conjointly with the housing in one 1 0mm direction onl 2,514,142 7/1950 Reid ..91/339 y 3,460,347 8/1969 Kurtz ..9l/339 2 Claims, 7 Drawing Figures P'A'TENTEUJUL 41972 3. 673 9,21

sum 1 or a INVENTORS RUSSELL A. FRITTS BY RE 50L? 3 ATTORNEY PATENTEDJUL 419. 2 v 3,678,921

sum 3 or 3 INVENTORS RUSSELL A. FRITTS ATTORNEY SUMMARY OF THE INVENTION The present invention is directed to a novel pressurized fluid mechanism, illustrated as a pneumatic mechanism, which includes a housing having an oscillating lever disposed in a chamber therein. Passage means and valve means is provided in the housing to deliver pressurized air alternately to opposite sides of the chamber whereby to oscillate the lever therein. The oscillating lever may be connected through a one-way clutch to an output member whereby to deliver unidirectional movement thereto.

Alternatively, a pair of chambers may be provided, each having an oscillating lever therein. In this case, passage and means is provided to oscillate the levers in opposite directions and each may be connected by a one-way clutch to the output member whereby the output member is substantially continuously driven in one direction.

Main objects of the present invention therefore are to provide a novel oscillating pressurized fluid motor and gearless mechanism adapted to deliver oscillatory or unidirectional rotary movement to an output member.

Further important objects of the present invention are to provide a novel motor and mechanism of the above character which is adapted for use as a wrench (e.g., nut-runner) in which oscillatory motor action is transmitted to unidirectional movement through a one-way clutch,.and which is adapted for use in the nature of a hand ratchet wrench, in which case the motor housing functions as a handle and the one-way clutch causes the handle and output member to turn conjointly in one direction only.

Additional important objects of the present invention are to provide a novel motor and mechanism of the above character which is relatively inexpensive to manufacture, rugged in construction, and reliable and efficient in use.

- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view illustrating a pneumatic tool embodying a preferred form of the present invention;

FIG. 2 is an enlarged exploded view of the tool of FIG. 1;

FIG. 3 is an enlarged plan view partly broken away, of the tool ofFlG. 1;

FIG. 4 is a sectional view of FIG. 3 taken along the line 4-4 thereof;

FIG. 5 is a schematic sequential view illustrating the movement of the motor parts;

FIG. 6 is a view similar to FIG. 4 but illustrating a modified form of the invention; and

FIG. 7 is a exploded perspective view of the structure of FIG. 6.

BROAD STATEMENT OF THE INVENTION Broadly described, the present invention relates to a pressu'rized fluid tool comprising a housing, an elongated fluid chamber formed in said housing and having an open end, lever means pivotally supported upon said housing and extending into said chamber, said lever means including an annular ring having an elongated paddle extending therefrom, said paddle extending into said chamber substantially the full length thereof with said annular ring closing the open end of said chamber, passage means including a pair of passages communicating with opposite sides of said chamber, valve means in said passage means and constructed to communicate a pressure supply with alternate ones of said passages and being operable in response to pressure differential in said passages, whereby to open the higher pressure passage and close the lower pressure passage to the pressure supply, exhaust port means in said chamber intermediate the sides thereof and communicated with alternate ones of said passages as said lever paddle oscillates, whereby said lever paddle moves in one direction away from the first passage having the higher pressure and toward a second passage having the lower pressure until said paddle passes said exhaust port means, whereby said exhaust port means is communicated with said first passage and is closed to said second passage, whereby pressure in said first passage drops and the pressure in said second passage increases, whereby said valve means is shifted and communicates said pressure supply to said second passage, whereby said lever paddle moves in the direction opposite said one direction.

DETAILED DESCRIPTION Referring now more specifically to the drawings, a portable pneumatic tool embodying a preferred form of the present invention is illustrated generally at 21 in FIGS. 1-4 and is seen to include an elongated body forming a motor housing 23 and comprising top and bottom covers 25, 27 and an intennediate spacer 29 arranged in sandwich fashion and secured together by screws 31. Compressed air is supplied to the housing 23 through a conduit 33 to drive a motor within the housing 23 and rotates an output member 35 to which a socket 40 may be attached in conventional wrench fashion. A throttle link 37 on the housing 23 controls the flow of air from the conduit 33 to the motor.

Turning now to FIGS. 24, the pneumatic motor is formed by a pneumatic chamber 39 defined by an elongated cut-out 41 in the spacer 29 and by the top and bottom covers 25, 27. A lolly-pop shaped lever 43 has an annular head 45 disposed between the top and bottom covers 25, 27 and closing the end of the chamber 39. A paddle-like lever 47 extends from the annular head 45 into the chamber 39.

The lever head 45 is pivoted on the housing 23 between the covers 25, 27 by suitable means. In this case, a drive shaft 49 is disposed within the lever head 45 and has reduced ends 51, 53 rotatably supported in openings 55, 57 in the top and bottom covers 25, 27. The output member 35 is keyed or otherwise secured to the shaft 49 and extends outwardly of the housing 23 for attachment to the socket member 40 by a suitable detent 5 0. A one-way clutch formed by a plurality of sprags 59 and a pair of springs 61 is disposed between the shaft 49 and the head 45 and transmits rotary movement from the head 45 to the shaft 49 in one direction while allowing these parts to move relative to one another in the other direction. For the parts shown, counterclockwise rotation of the head 45, as seen in FIGS. 1 & 2, causes the shaft 49 also to tum counterclockwise. The head 45, however, can turn clockwise relative to the shaft 49.

As shown in FIGS. 2-5, the pneumatic chamber 39 is substantially the same length and height as the length and thickness of the lever paddle 47. However, the width of the chamber 39 is somewhat greater than the width of the paddle 47 so as to allow pivotal movement of the lever 43 about the center of the head 45. As shown, the end wall of the recess 41 in the spacer 29 if formed substantially on a radius from the center of the head 45, and the side walls of this recess 41 lie in planes which also include the sides of the paddle 47 when at the sides of the chamber 39.

Air pressure is admitted to the chamber 39 from the conduit 33 by way of passage means in the housing 23 and is controlled by valve means also in the housing so that the lever 43 is rapidly oscillated about the axis of the head 45. Thus, the conduit 33 is connected by passages 60 and 62 formed in a coupling formed in a coupling 64 to an inlet passage 61 formed in the top cover 25. The passage 61 terminates in an inlet cavity 63 formed by aligned recesses 65, 67 in the top and bottom covers 25, 27 and an opening 69 in the spacer 29 and is normally closed by a ball 66 engaged by a spring 68. The inlet cavity 63 is communicated by a passage 70 in the spacer 29 with a valve cavity 71 formed by aligned recesses 73, 75 in the top and bottom covers 25, 27 and a stepped opening 77 in the spacer 29. A valve disk 79 is disposed in the opening 77 and, depending upon its position, communicates the pasage 70 with either a main passage 81 formed by grooves in the top cover 25 and upper side ofthe spacer 29, or a main passage 83 in the bottom cover 27 and lower side of the spacer 29. A small plate 82 is disposed in the opening 77 between the top cover 25 and the spacer 29 and defines an aperture 84 equal in cross section to an aperture 86 at the lower side of the opening 77. An annular seal ring 80 is positioned between the plate 82 and the top cover 25.

The main passages 81, 83 are communicated with opposite sides of both the chamber 39 and the lever paddle 47. Thus, by supplying pressurized air alternately to the main passages 81, 83, the lever 43 is oscillated about the axis of the head 45. Air is exhausted from the motor chamber 39 to atmosphere through an exhaust port 85, a cavity 87 (formed by a plate 88 secured to bottom cover 27 by a screw 90), a port 89 in the top and bottom covers 25, 27, and a cavity 91 (formed by a plate 94 secured to top cover 25 by a screw 96), and an opening 93. This relatively long air discharge passage system allows the exhaust air to expand into a partially enclosed chamber and greatly reduces exhaust noise.

In use, the throttle link 37 is moved by a means of a trigger 95 to unseat the ball 66 whereupon pressurized fluid is admitted to passage 61, inlet cavity 63, passage 70, and valve cavity 71. If the valve disk 79 is positioned as shown in FIG. 4, pressurized air is admitted through aperture 84 to recess 73, and flows to the motor chamber 39 by way of main passage 81. This causes the lever 43 to move in a counterclockwise direction, as viewed in NO. 5. When the lever paddle 47 passes the exhaust port 85, the pressure in front of the moving paddle 47 begins to rise rapidly while the pressure behind the paddle 47 rapidly drops. Since the top of the valve disk 79 (as seen in FIG. 4) is exposed to the pressure behind the paddle 47, and the bottom of the valve disk 79 is exposed to the pressure in front of the paddle 47 this rapid change in pressure lifts the valve disk 79 against the plate 82 so that now, pressurized air is delivered to the motor chamber 39 by way of main passage 83, After this shifting of the valve disk 79 occurs, momentum carries the paddle 47 to the limit of its movement in a counterclockwise direction (FIG. 5 A). However, now air is delivered to the motor chamber 39 by way of main passage 83 and begins to push the paddle 47 in a clockwise direction as viewed in FIG. 5. Here, again, the same sequence occurs. Thus, until the paddle 47 reaches the exhaust port 85, air pressure behind the moving paddle 47 remains high since it is sealed from exhaust, while air pressure in front of the moving paddle 47 remains low since it communicates with the atmosphere through port 85. Under these conditions, the pressure in recess 75 is somewhat higher then that in recess 73 and the valve disk 79 remains against the plate 82.

When paddle 47 passes exhaust port 85, air pressure behind the paddle 47 drops rapidly since it now communicates with exhaust port 85, while the pressure in front of the moving paddle 47 rinses since it is now sealed from exhaust. This causes the valve disk 79 to move away from plate 82 so that supply pressure is again delivered to motor chamber 39 by way of main passage 81. When the momentum of the moving paddle 47 is on ercome by the build up of air pressure in front of it, the direct on of its movement is again reversed. Desirably, this occurs when the paddle 47 approaches the side wall of motor chamber 39. Continued supply of air to the motor chamber 39 thus oscillates the lever 43.

In the illustrated construction, the one-way clutch which includes the sprags 59 and springs 61 disposed within the lever head 45 and around the shaft 49, converts the oscillatory movement of the lever 43 to counterclockwise rotation of the shaft 49, as seen in FIG. 3. However, the sprags 59 allow the lever 43 to turn clockwise relative to the to the shaft 49 as seen in this figure. Thus, when the wrench socket 40 is applied to a workpiece (such as a threaded fastener) and the tool turned on," the workpiece is turned in a clockwise direction (it being assumed that that tool 21 is turned over from the FIG. 3 position). This will serve to tighten a right-handed fastener (or to loosen a left-hand fastener). To then apply a further torque to a right hand fastener, the tool 21 with the socket 40 still in place on the fastener, can be used like 8 normal hund wrench. When so used, the housing 23 functions as a handle and torque is transmitted to the fastener through the sprags 59 when the handle (housing 23) is turned in a clockwise direction (when looking down on the top of FIG. 4). When the tool 21 is manually turned in the opposite direction, the sprags 59 free wheel.

The particular type of tool referred to here is commonly called a nut-runner tool and is used to run down and tighten threaded fasteners. Thus, powered operation quickly runs the fastener down to finger tightness, and final tightening is achieved by hand operation. Nut runners of this type have in the past often employed a rotary drive, a right-angle gear train, and a one-way clutch assembly to obtain the desired output. It will be appreciated that the present invention obviates the need for any right-angle gear train and, in fact, eliminates the need for any gears at all. With the construction illustrated and described above for FIGS. 1-5, the lever 43 can operate about 24,000 cycles per minute and turns the socket 40 at a speed of about 1,000 revolutions per minute. This construction is decidedly advantageous when compared to the somewhat heavier, and more expensive prior art versions which employ a right-angle gear transmission.

It will also be appreciated that the tool 21 can provide for drive of the socket 40 in the reverse direction, i.e., to loosen a right-hand or tighten a left-hand fastener, simply by attaching the socket 40 to the output member 35 at the other side of the housing 23. This is done by constructing the output member 35 so that it can extend to this other housing side and attaching the socket 40 thereto, as shown in dotted lines in FIG. 4.

FIGS. 6 and 7 illustrate a modified version of the present invention. In this embodiment, the tool, generally illustrated at 109, employes a pair of levers which oscillate oppositely to one another. Thus, these levers may be connected to the same output shaft through one-way clutch means to transmit substantially continuous unidirectional rotary movement thereto.

As seen in FIGS. 6 and 7, this embodiment includes top and bottom covers 111, 113, upper and lower spacers 115, 117, and a divider 119, all of which are secured together in sandwich fashion by screws 121. A pair of motor chambers are defined by open recesses 123, in the spacers 115, 117, respectively closed at their top and bottom by the top cover 111 and spacer 119, and the spacer 119 and bottom cover 1 13, respectively. An upper lever 127 has an annular head 129 disposed between the top cover 111 and the spacer 119, and a paddle 131 extending into the chamber 123. A lower lever 133 has an annular head 135 disposed between the spacer 119 and bottom cover 113, and a paddle 137 extending into the chamber 125. A pair of one- way clutches 139, 141 are disposed within the lever heads 129, 135 and surround an output shaft 143 which extends through an opening in the spacer 119 and has reduced portions 142, 144 joumalled in openings 146, 148 in the top and bottom covers 111, 113, respectively. An output member 145 is keyed in the shaft 143 and is adapted to extend outwardly therebeyond from either side thereof. A wrench socket 147 may be attached to the ex tending end of the member 145 and is releasably retained thereon by detent means 149.

Pressurized air is supplied to the tool 109 from a source through a conduit 153. Like the embodiment of FIGS. 1-5, a throttle valve including a ball 154 and spring 156 is actuated by a throttle line (not shown) to admit pressurized air to the tool 109. When the throttle valve is opened, pressurized air is admitted to an inlet cavity 157 by way of an inlet passage 159 in the top cover 111. The cavity 157 is connected to a valve cavity 161 by cutout 163 in the divider 119, and the cavity 161 is selectively communicated, through operation of a valve disk 162, with a main passageway 165 fonned in the top cover 111 and upper spacer 115, or with a main pasageway 167 formed in the bottom cover 113 and lower spacer 117. The main passageway 165 communicates with one side of the motor chamber 123 and with the other side of the motor chamber 125 by way of aligned apertures 169, 171, 173 in the upper spacer 115, the divider 119, and lower spacer 117, respectively, and a passageway 175 in the lower spacer 117 and bottom cover 113. Similarly, main passageway 167 communicates with one side of the motor chamber 125 and with the other side of the motor chamber 123 by way of an aperture 177 in the lower spacer 117, and aperture 179 in the divider 119, an aperture 181 in the upper spacer 115, and a passageway 183 in the top cover 1 l1 and upper spacer 115.

Thus, when air pressure is admitted to main passageway 165, it swings the lever 127 clockwise and the lever 133 counterclockwise as viewed in FIG. 7. Alternatively, with air pressure is admitted to passageway 167, the lever 127 swings counterclockwise and the lever 133 clockwise. The one- way clutches 139, 141 are substantially identical, i.e., they are constructed to transmit rotation to the output shaft 143 in one direction only that direction being the same for both clutches. Since the levers 27, 133 pivot in opposite directions, one is always driving the shaft 143 while the other is free wheeling. The result is that the shaft 143 is driven substantially continuously in one direction.

The operation of this modification is substantially the same as that described for FIGS. 1-5 above. Thus, with the valve disk 162 in the lower position shown in FIG. 6, supply air is delivered to passageways 165 and 175 and pivots the lever 127 clockwise and the lever 133 counterclockwise. Air in front of the paddles 133, 137 is exhausted through ports 185, 187. The air which exists through upper port 185 goes directly to atmosphere through an opening 189 formed between the top cover 1 1 1 and a removable plate 190, while the air from larger lower port 187 enters an expansion cavity 191 between the bottom cover 113 and a removable plate 192, from where it passes through openings 193, 195, 197, 199 in the bottom cover 113, the lower spacer 117, the divider 119, and upper spacer 115, respectively, and thence to the atmosphere through opening 189. Like in the embodiment of FIGS. 1-5, the purpose of this expansion of exhaust air is to muffle the sound.

Before the paddles 131, 137 pass the exhaust ports 185, 187, air pressure behind the paddles is high while that in front of the paddles is exhausted to the atmosphere through ports 185, 187. Thus, air pressure above the valve disk 162 is higher than that below it so the disk remains in this position. However, when the paddles 131, 137 pass the ports 185, 187, air pressure behind the paddles drops rapidly while that in front rises correspondingly. Momentum carries the paddles 131, 137 to the end of their strokes; however, this change in pressure within the tool 109 shifts the valve disk 162. Now, supply air is delivered to passageways 167, 183 and swings levers 127, 133 counterclockwise and clockwise respectively.

As in the embodiment of FIGS. 1-5, the direction of rotation imparted to the socket 147 is reversed by mounting the socket on the other end of the output member 145, when the latter is positioned as shown in dotted lines in FIG. 6. Also, the tool 109 can function as a hand ratchet wrench, to for example, apply a final torque to a threaded fastener, by using the elongated housing in the manner of a handle. The one- way clutches 139, 141 cause the output member to turn conjointly with the tool housing in one direction while allowing the member 145 to free wheel" in the other direction.

While preferred embodiments of the present invention have been illustrated and described in detail herein, it will be appreciated that the present invention transcends these embodiments and find use in the broad class of pressurized fluid devices. Further, it will be appreciated that substitutions, modifications and omissions may be made thereto without departing from the spirit of the invention.

We claim:

1. A pressurized fluid tool comprising a housing, an elongated chamber formed in said housing and having an open end, lever means pivotally supported upon said housing and extending into said chamber, said lever means including an annular ring having an elongated paddle extending therefrom, said paddle extending into said chamber substantially the full len thereof with said annular ring closing the open end of sai chamber, passage means including a pair of passages communicating with opposite sides of said chamber, valve means in said passage means and constructed to communicate a pressure supply with alternate ones of said passages and being operable in response to pressure differential in said passages, whereby to open the higher pressure passage and close the lower pressure passage to the pressure supply, exhaust port means in said chamber intermediate the sides thereof and communicated with alternate ones of said passages as said lever paddle oscillates, whereby said lever paddle moves in one direction away from a first passage having the higher pressure and toward a second passage having the lower pressure until said paddle passes said exhaust port means whereby said exhaust port means is communicated with said first passage and is closed to said second passage, whereby pressure in said first passage drops and the pressure in said second passage increases, whereby said valve means is shifted and communicates said pressure supply to said second passage, whereby said lever paddle moves in the direction opposite said one direction.

2. A tool as defined in claim 1 wherein said valve means includes a cavity in said housing having a disk movably disposed therein, said first and second passage passages with opposite ends of said cavity, said pressure supply communicating with said cavity intermediate said ends.

* i i I t v UNITED STATES PATENT OFFICE CERTIFICATE OF COECTION Patent No. 3,673,921 I Dated July 4, 1972 Inventor(s)RuSSell A. Fritts, Jerome I. Rebold It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 61 delete formed in a coupling.

Column 3, line 34, after the numeral "83" the comma should be a period i Column 3, line 50, the word rinses should be rises a Column 3, line 64, after the word "relative" remove to the.

Column 3, line 68, after the word "assumed" remove that.

Column 4, line 16, after the word "operate" insert at.

Column 5, line 5, the word "and" should be an.

Column 5, line 10 the word "with" should be when.

Column 6, line 47, after the word "second" remove passage and after the word "passages" insert communicating.

Signed and sealed this 6th day of February 1973..

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM PO-1050 (1069) USCOMM-DC 60376-P69 fl' U 5. GOVERNMENT PRINTING OI'IICI: I!" 0-3584

Claims (2)

1. A pressurized fluid tool comprising a housing, an elongated chamber formed in said housing and having an open end, lever means pivotally supported upon said housing and extending into said chamber, said lever means including an annular ring having an elongated paddle extending therefrom, said paddle extending into said chamber substantially the full length thereof with said annular ring closing the open end of said chamber, passage means including a pair of passages communicating with opposite sides of said chamber, valve means in said passage means and constructed to communicate a pressure supply with alternate ones of said passages and being operable in response to pressure differential in said passages, whereby to open the higher pressure passage and close the lower pressure passage to the pressure supply, exhaust port means in said chamber intermediate the sides thereof and communicated with alternate ones of said passages as said lever paddle oscillates, whereby said lever paddle moves in one direction away from a first passage having the higher pressure and toward a second passage having the lower pressure until said paddle passes said exhaust port means whereby said exhaust port means is communicated with said first passage and is closed to said second passage, whereby pressure in said first passage drops and the pressure in said second passage increases, whereby said valve means is shifted and communicates said pressure supply to said second passage, whereby said lever paddle moves in the direction opposite said one direction.

2. A tool as defined in claim 1 wherein said valve means includes a cavity in said housing having a disk movably disposed therein, said first and second passage passages with opposite ends of said cavity, said pressure supply communicating with said cavity intermediate said ends.

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