US2964151A

US2964151A - Automatic supply and shut off of motive fluid for torque tool

Info

Publication number: US2964151A
Application number: US777285A
Authority: US
Inventors: Richard E Eckman
Original assignee: Reed Roller Bit Co
Current assignee: Reed Roller Bit Co
Priority date: 1958-12-01
Filing date: 1958-12-01
Publication date: 1960-12-13
Anticipated expiration: 1977-12-13

Description

Dec. 13, 1960 R. E. ECKMAN 2,964,151

AUTOMATIC SUPPLY AND SHUT OFF OF MOTIVE FLUID FOR TORQUE TOOL Filed Dec. 1, 1958 3 Sheets-Sheet 1 INVENTOR. ?/cfi 0/0 E. [CA man BY v 6 ATTORNEY Dec. 13, 1960 R. E. ECKMAN 2,964,151

AUTOMATIC SUPPLY AND SHUT OFF OF MOTIVE FLUID FOR TORQUE TOOL Filed Dec. 1, 1958 3 Sheets-Sheet 2 H1 d 8 2 30 f 44 77 7/ A J \l \L 7 47 J5 36 40 37 42 71 52 34 v 27-\ A .4. J .A Q

' INVENTOR. fi/cfioro f. Eek/7700 ATTORNEY R. E. ECKMAN Dec. 13, 1960 AUTOMATIC SUPPLY AND SHUT OFF OF MOTIVE FLUID FOR TORQUE TOOL 3 Sheets-Sheet 3 Filed Dec. 1, 1958 THO AUTOMATIC UPPLY AND SHUT OFF OF MOTIVE FLUID FOR TORQUE TOOL Richard E. Eckman, Houston, Tex., assignor to Reed lTkoller Bit Company, Houston, Tex., a corporation of exas Filed Dec. 1, 1958, Ser. No. 777,285

9 Claims. (Cl. 192--.034)

This invention pertains broadly to portable fluid actuated tools such as used for setting threaded elements, but more particularly to a mechanism controlling the supply and shut oif of motive fluid to such a tool.

One object of this invention is to provide a pressure fluid actuated tool with a throttle valve operating mechanism adapted to automatically open the throttle valve when the tool is applied to the work, and to automatically shut off the throttle valve when the work has been set to a predetermined extent, even though the tool is still applied to the work.

Another object of this invention is to provide such a tool with a motive fluid supply control mechanism movable to a first position whereby motive fluid is automatically supplied to the tool when the tool is applied to the work, automatically to a second position to shut off supply of motive fluid to the tool when the work has been set to a predetermined extent, and automatically to its first position upon removal of the tool from the work.

Another object of this invention is to provide such a tool with simple and dependable means for adjusting, within a relatively large range, the maximum torque out put of the tool, and provide simple and efilcient means for automatically shutting ofl the throttle valve when such torque has been reached.

Other objects and advantages more or less ancillary to the foregoing reside in the specific construction and aggroupment of the elements peculiar to this structure, as will become apparent from a more complete examination of this specification.

in the drawings:

Fig. l is a side elevational view, partly in section, of a tool embodying the invention.

Fig. 2 is enlarged side elevational fragmental view, partly in section, of the tool shown in Fig. 1.

Fig. 3 is a view corresponding to Fig. 2, showing a portion of the tool with parts in diflerent positions.

Fig. 4 is a side elevational fragmental sectional View with parts shown in still different positions, and

Fig. 5 is a cross sectional view taken on line 55 in Fig. 4.

Referring to the drawings in which like symbols designate corresponding parts throughout the several views, generally designates the tool embodying the invention, which tool comprises a housing 11 formed of several sections screw threaded together and depicting generally a smooth cylindrical housing adapted to be comfortably held by the operator. Within the right end portion of this housing is mounted a pressure fluid actuated vane type motor 12 well known in this art. This motor generally includes a stator 13 in which is located a rotor 14 journalled within adequate bearings 15 and carrying the usual radially movable vanes 16. Within the right end of the housing 11 is screwed a motive fluid connection 17 within which may be screwed one end of a flexible conduit, not shown, supplying motive fluid to an inlet chamber 18. The inner end of the chamber 18 constitutes an annular shoulder forming a valve seat 19' from which leads a coaxial inlet port 2h communicating with a system of inlet passageways 21 leading to the stator 13- for supplying motive fluid to the vanes 16 and actuate the motor in the usual way. Within the inlet chamber 18 is located a throttle valve 22 carrying an O-ring seal 23, which valve is normally held in fluid tight engagement with the valve seat 19 by a compression spring 24. It will thus be understood that the spring 24 normally urges and maintains the valve 22 in the closed position shown in Fig. 4, in which position the pressure fluid is shut off from the motor 12.

The left end portion of the housing 11 is reduced as at 26 and adequately machined to accommodate a slidable work guide piece 27 rotationally looked to the housing portion 26 by a key 28. This key extends through a radial hole 29' provided through the housing wall and is carried by a removable split ring 30. In order to limit the forward movement of the guide piece, the key is engageable with the inner end of its key slot 31 provided in the guide piece, which guide piece is urged forwardly by a compression spring 32 interposed between the right end of the guide piece and a shoulder 33 formed within the housing 11. The guide member 27 has its forward end internally shaped to fit over the work such as a screw or the like, and has slidably mounted therein the forward end of a tool implement 34. The rear end portion of the tool implement is provided with an hexagonal shank 35 detachably mounted within a corresponding bore 36 provided Within the front shafted end portion or socket 3-7 of a sleeve spindle 38. The shank 35 is retained within the socket 37 against accidental removal therefrom by the usual spring detent 39 extending within an annular groove 40' formed intermediate the ends of the shank. The length of the groove is sufficient to enable slidable movement of the shank relative to the socket, and under certain conditions of operation the engagement of the inner end 41 of the shank with the inner end 42 of the socket. The right end portion of the spindle 38 is slidably mounted Within the bore 43 of a tubular driven clutch member 44, and is rotationally locked thereto by cooperating splines 6'7 provided on the sleeve and within the bore 43. The right end portion of the driven clutch member 44 is enlarged to a head 45 provided with a smooth central bore 46 adequately machined for running fit over a driving clutch member 47, which has its left end reduced to form an annular shoulder 48 resting against the flat bottom of the bore 46 and a pilot 50 journalled within the bore 43 of the clutch member 44. The right end 51 of the driving clutch member 47 is also reduced and preferably of hexagonal shape to fit closely within the corresponding bore 25 of a motor spindle 49 where it is rotationally locked thereto for rotation therewith. The motor spindle 49 is adequately supported within bearings 53 one of which is shown in Fig. 4 and derives its rotation from the motor 12 through a train of speed reduction gears, not shown, which train is connected at its input end to the rotor 14- of the motor 12 and. at its output end to the motor spindle 49. Adjacent its shoulder 48, the driving clutch member 47 is provided with a polygonal cam 52, which in this instance is shown to be of the hexagonal type having six sides 54 equidistant from the center axis of the ciutch member and joined by six points or vertexes 55 also equidistant from that axis. Adjacent the cam 52, the head 45 of the clutch member 44 is provided with six equally spaced'bores 56 which extend radially through the head 45 and have their center axes located within a vertical plane in Fig. 4 passing through the sides 54 of the cam at substantially one half the width thereof. Each bore has a detent or ball 57 closely fitted therein for free movement relative to the driven clutch member, which at this location constitutes a ball carrier having a wall thickness materially smaller than the diameter of the balls to enable the balls to project beyond the inside and outside walls of the clutch member.

The balls 57 are normally maintained against the sides 54 of the cam 52 by the inwardly inclined wall 58 of a ball retainer 59 mounted on the clutch member 44 for movement relative thereto. This retainer forms a cam urged against the balls 57 by the force of a compression spring 60 mounted around the left end portion of the clutch member with one end engaging a spring follower 61 slidably mounted on the driven clutch member 44 but rotationally locked thereto by a key 62 fitted within a key slot 63. The spring follower 61 is axially adjustable on the clutch member 44 by an adjustment nut 64 screwed on the left end of the driven clutch member. The other end of the spring 60 engages a second spring follower 65 Which is free to slide and rotate on the driven clutch member 44 to transmit the force of the spring 60 to the ball retainer or cam 59 through a needle bearing assembly 66, thereby enabling free rotation of the ball retainer irrespective of the axial forces to which it is subjected by the spring 60.

Within its right end portion, the spindle 38 is provided with a central bore 68 opening through the right end of the sleeve. This bore is reduced in diameter as at 69 to form an internal annular shoulder 70. In this bore is slidably mounted a valve actuating plunger 71 which is urged to the right by a compression spring 72. This plunger engages the inner end of a throttle valve rod 73 which extends from the throttle valve 22 through the motor 12 and driving clutch member 47 and terminates within the right end of the spindle bore 68. While the plunger is always spring biased against the inner end of the rod 73, it must be understood that the force of the spring 72 is not sufiicient to open the throttle valve 22 against the stronger force of the valve spring 24. The plunger 71 is provided with an elongated slot 74 within which a pawl or sear 75 is pivotally mounted by a cross pin 76. The free end portion of the sear is biased outwardly into the bore 68 of the spindle 38 by a resilient member 77 mounted within the plunger 71, thus under certain conditions of operation the free end of the sear is engageable with the annular shoulder 70 forming the bottom end of the spindle bore 68. The depth of the slot 74 is sufiicient to accommodate the free end por tion of the sear upon compression of the resilient member 77, in which instance the sear is free to move with the plunger 71 into the reduced portion 69 of the bore 68 as clearly shown in Fig. 3. An elongated slot 78 is also provided through the Wall of the tubular driven clutch member 44, which slot .is aligned with the slot 74 and with a third slot 79 provided through the wall of the spindle 38. Within .the slot 78 ispivotallymounted by a cross pin 80 an S-shaped lever 81 having one arm resting against a skirt 82 extending from the spring follower 65 and another arm extending through the slot 79 for engagement with the sear 75.

When the tool is applied to the work, such as a screw or the like, intended-to be driven thereby, theguidermember 27 is first positioned on the work. Thereafter the operator exerts an axial force on the tool toward the work, thereby causing the tool implement 34 to operatively engage the work. As the operator maintains his axial pressure on the tool, the tool implement while operatively engaging the work continues its. axially inward movement within the housing 11 and transmits this axial inward movement to the spindle 38 by the engagement of the inner .end 41 of the tool implement with the bottom end 42 of the socket 36. In'this instance the parts are located as shown in Fig. 2, that is with the freeend of the sear 75 'engaging'the bottom 70 of the'spindle bore 68, thereby transmitting the inward movement of the spindle to the plunger, and causing the plunger to exert pressure on the free end of the valve rod 73 to open the valve .22 against the spring 24. 'Upon opening of the throttle valve, motive fluid from the inlet chamber 18 is free to flow to the motor 12 through the inlet port 20 and passages 21 to actuate the motor and impart rotation to the driving clutch member 47. From the driving clutch member, rotation is transmitted to the driven clutch member 44 by the balls 57 maintained in engagement with the fiat sides 54 of the cam 52, and from the clutch member 44 to the spindle 38 and the tool implement 34.

When the free running of the work is completed, seating resistance gradually increases until the Work is fully set and prevented from further rotation, thereby causing the tool implement 34, spindle 38 and clutch member 44 to remain stationary even through the motor 12 is still operating. In this instance rotation of the clutch member 47 relative to the clutch member 44 causes the vertexes 55 of the cam 52 to pass under the detents 57, thereby imparting to the detents a rolling impulse, which is unrestricted by the ball retainer 59 free to rotate on the needle bearing 66. During this rolling impulse of the detents, they are also moved radially outward, thereby exerting outward radial forces on the inclined wall 58 of the detent carrier 59 to move it axially toward the work by compressing the spring 60. This axial movement of the detent retainer is transmitted to the spring follower 65 through the needle bearing 66, thereby causing the skirt 82 of the spring follower to exert a force on the lever 81 to effect its clockwise pivotal movement and consequently move the sear 75 to the position shown in Fig. 3, that is out of end engagement with the bottom 70 of the spindle bore 68 by compressing the resilient member 77. This movement of the sear 75 from a cocked to an uncooked position releases the plunger 71 from the sleeve 38 and enables the throttle valve 22 to be closed by the spring 24, while the plunger is moved against the spring 72 by the throttle valve rod 73. It will be noticed that this automatic closing of the throttle valve or shutting ofi of the motor is effected even though the operator is still exerting an axial force on the tool to maintain the tool implement 34 in operative engagement with the work.

After the vertexes 55 of the cam 52 have passed once under the balls 57 by imparting a rolling impulse thereto, the cam again assumes the position shown in Fig. 5 with the balls engaging the flat sides of the cam, thereby enabling the ball retainer 59 to be moved axially to the right by the spring 60 to relieve the force of the spring follower 65 on the lever 81, which had caused the clockwise pivotal movement of the lever. vBy using a polygonal cam of the hexagonal type, it will be understood that the clutch member 47 or cam 52 needs to rotate only 30 relative to the clutch member 44 in order to release the sear 75 from the sleeve 38, thereby causing the motor 12 to be automatically shut ofi almost immediately after the work has been set.

As the tool is removed from the work, the axial pressure previously exerted on the tool is released, thereby causing the several parts through the action of the

springs

32 and 72 to again assume the position shown in Fig. 4. In this instance the sear 75 through the resilient member 77 is pivotally moved counterclockwise to a cocked position, wherein its free end engages the sleeve annular shoulder 70.

It will be understood that the pawl or sear 75 forms a releasable connection between the spindle 38 and plunger 71, which is automatically released upon a predetermined resistance to rotation of the tool implement 34 .or spindle 38. The spindle 38 and plunger 71 may also be constructed as an extension between the tool implement and valve rod 73, which is releasable upon clockwise pivotal movement of the sear 75. The spindle .38 and plunger 71 are mounted for telescoping movement, which in one direction is cushioned by the spring .72

and under certain conditions of operation that movement 'in that direction is prevented by the sear 75.

From the foregoing description it will be understood that the tool is equipped with a simple and efficient mechanism adapted to automatically supply motive fluid to the motor 12 when the tool is applied to the work, and to automatically shut ed the supply of motive fluid when the work has been set to a predetermined extent, even though the tool is still applied to the work. It will further be understood that the extent to which the work may be set, or more specifically the torque output of the tool, is adjustable by varying the compression of the spring 60 through the nut 64.

Although the foregoing description is necessarily of a detailed character in order to completely set forth the invention, it is to be understood that the specific terminologyqis not intended to be restrictive or confining, and it is to be further understood that various rearrangement of parts and modifications of structural details may be resorted to without departing from the scope or spirit of the invention as claimed.

I claim:

1. In a tool of the character described, a housing, a fluid actuated rotary motor within said housing, a passageway adapted to supply motive fluid to actuate said motor, a valve controlling said passageway, a spring biased on said valve normally closing the valve relative to said passageway, a tool implement drivenly connected to said motor, said tool implement under certain conditions of operation moving axially inward of said housing, cooperating telescoping elements between said tool implement and valve, means including a pawl pivotally carried by said one of said elements adapted to lock said elements axially in one direction whereby the axial inward movement of said tool implement is transmitted to said valve to open it relative to said passageway, and means responsive to a predetermined torque resistance of said tool implement to release said pawl and enable said valve to be closed relative to said passageway by said spring while efiecting telescoping movement of said elements in said one direction.

2. In a tool of the character described, a housing, a fluid actuated rotary motor within said housing, a passageway adapted to supply motive fluid to actuate said motor, a valve movable to open or close positions rela tive to said passageway, a tool implement drivenly connected to said motor, said tool implement when applied to the work moving axially inward of said housing, cooperating telescoping elements between said tool implement and valve, a pawl cooperating with said elements movable to a first position to lock said elements against telescoping movement in one direction whereby the axial inward movement of said tool implement is transmitted by said elements to said valve to open it relative to said passageway, and means responsive to a predetermined torque resistance of said tool implement to move said pawl to a second position permitting said telescoping movement in said one direction to enable said valve to be closed relative to said passageway by said spring.

3. In a tool of the character described, a housing, a fluid actuated rotary motor within said housing, a passageway adapted to supply motive fluid to actuate said motor, a valve movable to open or close positions relative to said passageway, a tool implement drivenly connected to said motor, said tool implement when applied to the work moving axially inward of said housing, cooperating telescoping elements between said tool implement and valve, a pawl cooperating with said elements movable to a first position to lock said elements against telescoping movement in one direction whereby the axial inward movement of said tool implement is transmitted by said elements to said valve to open it relative to said passageway, means responsive to a predetermined torque resistance of said tool implement to move said pawl to a second position permitting said telescoping movement in said one direction to enable said valve to be closed relative to said passageway by said spring, and means automatically moving said pawl to said first position when the tool implement is removed from the work even though said valve is still closed relative to said passageway.

4. In a pressure fluid actuated tool for running and setting a threaded element, a housing, a fluid actuated rotary motor within said housing, a spindle movable under certain conditions of operation axially inward of said housing, a rotation transmitting clutch means between said motor and spindle automatically releasable upon a predetermined resistance to rotation of said spindle, a valve controlling the supply of motive fluid to said motor, a valve opening member on said spindle, a releasable pawl cooperating with said spindle and member normally transmitting the axial inward movement of said spindle to said member and valve to open the valve, means responsive to the release of said clutch means to release said pawl, and means closing said valve upon the release of said pawl.

5. In a pressure fluid actuated tool for running and setting a threaded element, a housing, a fluid actuated rotary motor within said housing, a spindle movable under certain conditions of operation axially inward of said housing, rotation transmitting clutch means between said motor and spindle automatically releasable upon a predetermined resistance to rotation of said spindle, a valve controlling the supply of motive fluid to said motor, a valve opening member axially movable on said spindle, releasable locking means between said spindle and member normally transmitting the axial inward movement of said spindle to said member and valve to open the valve, means responsive to the release of said clutch means to release said locking means, and means closing said valve upon the release of said locking means.

6. In a tool of the character described, a housing, a fluid actuated rotary motor within said housing, a spindle movable axially inward of said housing when the tool is applied to the work and axially outward of said housing when the tool is removed from the work, rotation transmitting clutch means between said motor and spindle automatically releasable upon a predetermined resistance to rotation of said spindle, a valve controlling the supply of motive fluid to said motor, a valve opening member axially movable on said spindle, locking means cooperating with said spindle and member movable to operative and inoperative positions, said locking means when in said operative position transmitting the axial inward movement of said spindle to said member and valve to open the valve, means responsive to the release of said clutch means to move said locking means to said inoperative position, means closing said valve upon movement of said locking means to said inoperative position, and means moving said locking means to said operative posi tion upon the axial outward movement of said spindle.

7. In a tool of the character described, a housing, a fluid actuated rotary motor within said housing, a spindle movable axially inward of said housing when the tool is applied to the work and axially outward of said housing when the tool is removed from the work, rotation transmitting clutch means between said motor and spindle automatically releasable upon a predetermined resistance to rotation of said spindle, a valve controlling the supply of motive fluid to said motor, a valve opening member on said spindle, a sear between said spindle and member adapted to be cocked to transmit the axial inward movement of said spindle to said member and valve to open said valve, means automatically cocking said sear upon the axial outward movement of said spindle, means responsive to the release of said clutch means to release said scar, and means closing said valve upon the release of said sear.

8. A tool comprising a housing, a fluid actuated motor within said housing, a spindle movable axially inward of said housing under certain conditions of operation, rotation transmitting clutch means between saidv motor and spindle enabling under other conditions of operation relative rotation therebetween, a valve controlling the supply of motive fluid to actuate said motor, first means movable to one position to open said valve and to a second position enabling said valve to be closed, means responsive to the axial inward movement of said spindle to move said first means to said one position, means responsive to the relative rotation of less than one revolution .between said motor and spindle to move said first means to said second position, and means closing said valve upon movement of said first means to said second position.

9. A tool comprising a housing, a fluid actuated motor within said housing, a spindle movable axially inward of said housing under certain conditions of operation, rotation transmitting clutch means between said motor and spindle enabling under other conditions of operation relative rotation therebetween, a valve controlling the supply of motive fluid to actuate said motor, first means movable to one position to open said valve and to a second position enabling said valve to be closed, means responsive to the axial inward movement of said spindle to move said first means to said one position, means responsive to a 30 relative rotation between said motor and spindle to move said first means to said second position, and means closing said valve upon movement of said first means to said second position.

References Cited in the file of this patent UNITED STATES PATENTS 2,484,364 Whitledge Oct. 1, 1949 2,499,708 Whitiedge May 7, 1950 2,518,049 Mosier Aug. 8, 1950 2,580,607 Schmid Jan. 1, 1952 2,730,212 Rice et al. Jan. 10, 1956 2,834,442 Sturrock May 13, 1958 2,860,603 Heidler Nov; 18, 1958