US1494064A - Pressure-fluid percussive tool - Google Patents

Description

may 13 1924.

' G. H. GILMAN PRESSURE FLUID PERcUssIvE TOOL Fled June 7, 1915 l. IFHAL mi l1.

lllllll Patented May 13, 1924.

UNITE@ STATES PATENT OFFICE.

GEORGE H.' G TLMAN, OF CLAREMONT, NEW I-IAIPSHIRE, ASSIG-NOR TO SULLIVAN MACHINERY COMPANY, F BOSTON, MASSACHUSETTS, A CORPORATION OF MASSA- CI-IUSETTS.

'PRESSURE-FLUID PERCUSSIVE TOOL.

Application filed .Tune 7, 1915.

7 '0 @ZZ fw ,71.0 m zt may con cern Be it known that l, GEORGE H. CriLMAN,

a citizen ot the United States. and a resident of Claremont, Sullivan County, rNew Hampshire, have invented an lm provement in Pressure-Fluid Percussive Tools, of which the following description, in conne-ction with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

This invention relates to pressure fluid percussive tools, and is more particularly, though not exclusively, concerned with a percussively acting drill ot' the hammer type having a hollow drill steel, into which pres sure luid is discharged to clear the hole ol its cuttings.

My invention will be best understood by reference to the following specification. when taken in connection with the accompanying drawings of one specific embodin ment thereof, while its scope will be more particularly pointed ont in the appended claims.

In the drawings:

Fig. 1 is a. plan of a pressure fluid tool embodying my invention, the forward portions of the drill steel being broken away;

Fig. 2 is a sectional view of the same :se on line 2-2 of Fig. 1, showing a portion of the drill steel and a portion of the handle broken away; and

Figs. 3 and 4L- are detail sectional views on line 3 of Fig. 1, showing diii'erent positions of the piston and the piston-controlling valve.

Referring to the drawings, and to the embodiment of my invention which I have selected for illustration, 1 have there shown a pressure Huid percussive tool of the hammer type, having a cylinder 5 provided with a piston chamber 6, in which a piston 7 is arranged to reciprocate. In t-he specific example, the piston is provided with an exten r sion constituting` a hammer bar 8, which reciprocates in a front cylinder head 9, and strikes the inner end ot a drill-'bit 10 loosely held in a chuck sleeve 11 of a chuck 12, which latter is rotatably mounted in a forward extension 13 ot the cylinder head 9.

Serial No. 32,516.

Rotation may be imparted to the chuck 12 and drill-bit 10, by the piston 7, through the use of suitable rotating mechanism of the type forming the subject matter ot U. S. Letters Patent No. 1,034,010, granted to the Sullivan Machinery Company as my assignee July 30th, 1912, or ot U. S. Letters Patent No. 1,103,002, granted to the Sullivan Machinery Company July 7th, 1914, as assignee of George H. Gilman and Lee A. Knights. In the mechanism of each of said patents, the reciprocative movement of the piston is utilized to impart a st-ep-bystep rotative movement to the: chuck and the drill-bit held thereby in a well-known manner. which it will be unnecessaryhere to describe, as it forms no essential part of my present invention. In the accompanying drawings, 14 is the rotating mechanism which is similar to that of said patents, and receives its rotative movement from the piston through the use of one or more helical grooves 15 formed in the hammer bar 8, which latter is splined to the chuck 12 by one or more keys 16 working in corresponding keyways 17 formed in the hammer bar. A. further illustration and description of the rotating mechanism is deemed unnecessary to a proper understanding of the subject matter of my present invention.

The drillbit 10 is herein provided with an axial hole 18, to which gaseous fluid and liquid may be applied for the purpose of expelling the cuttings and laying the dust. As herein shown. the tool is provided with a liquid conducting tube 19, which extends 'trom a rear cylinder head 20 axially through the piston 7. This tube, however, forms no part of my invention herein. and may 'be omitted if desired. It should be noted, however, that as shown, the tube where it extends into the axial passage 18 of the drill-bit 10 is separated from the wall of the passage by an annular space, affording a means of communication between the hollow drill-bit and the chamber 21 within the chuck 12. Into the chamber 21 pressure fluid may be admitted from the cylinder chamber 6,'by way of the grooves 15 and 17, or either of them, by simply providing the necessary clearances. One or more of these grooves may enter into the cylinder chamber during the rearward stroke of the piston, and conduct motive fluid from the cylinder chamber 6 to the chuck chamber' 21, from whence it will pass to the drill-bit.

The piston 7 may be controlled in its reciprocations by any suitable type of valve, but for the purposes of illustration, I have herein shown a valve similar to that forming the subject matter of Officer Patent 7 33,229, dated September 8, 1903, and Gilman Patent No. 1,030,466, dated June 25, 1912. In the specific example herein shown, 22 is a controlling valve of the pressure Huid pistoncontrolled type, having a central spool 23, which alternately connects a supply chamber 24, with ports 25 and 26, the former leading to the rear or head end of the cylinder, and the latter to the forward or tool end of the cylinder. In the position of the valve shown in Fig. 2, pressure fluid passes from the supply chamber 24 through the port 25 to the rear end of the cylinder, acting to drive the piston forward, the port 26 at the same time being connected about the contracted or stem portion of the valve, with one end of an exhaust space 27. IVhen the valve is reversed, the port 26 is connected with the supply chamber 24, and the port 25 is connected with the opposite end of the exhaust space 27.

To reverse the valve, the latter is provided at opposite ends with spools 28 and 29, which work in chambers 30 and 31, to which pressure Huid is alternately admitted by the movement of the piston to throw the valve. The chamber 30 is connected by a passage 32 to the forward portion of the cylinder chamber 6, while the chamber 31 is connected by a passage 33 to the rear portion of the cylinder chamber, so that such passages are alternately opened by the piston in its reciprocatory movement to admit pressure iiuid to that end of the valvel chamber with which the uncovered passage is connected, and to exhaust the pressure fluid from the opposite end, such. admission of pressure liuid reversing the position of the valve. Such type of valve is well-known, and requires no further description, it being herein disclosed and referred to merely as a type of any pressure-fluid actuated valve,

the particular form and construction of such valve being immaterial for the purposes of the present invention. In the operation of tools of this class, it frequentlyv becomes desirable to withdraw the drill-bit from the drill hole, meantime supplying pressure fluid continuously to the drill-bit to cause the discharge of the cuttings from the drill hole, and to stop the percussive action of the hammer piston on the drill-bit. It is desirable, however, that during the withdrawal of the drill-bit, the latter shall be rotated to assist in clearing the hole of its cuttings, and to prevent the drill-bit from sticking as it is withdrawn. To this end, therefore, I have provided means for limiting the movement of the valve to less than normal, to cause the operation of the piston with a reduced amplitude of movement, while maintaining communication between the motive fluid supply and the drill steel by way of the cylinder chamber. Such reduced movement of the piston, while insufficient to cause it to strike the drill-bit, is still great enough to operate the rotating mechanism.

These desirable results can be attained very conveniently by the use of a manuallyoperated push pin or push button 34 arranged at either end of the valve, herein at its forward end, so as to limit the motion of the valve in that direction to less than normal. In the present exemplification, the movement of the valve is checked by buffers 35 and 36, the latter bearing against suitable springs 37 and 38, perforated to receive tie rods or bolts 39 and 40, having threaded ends engaging nuts 41 and 42. The buffer 36 forms a convenient housing for the push button or push pin 34, and for that pui pose is herein provided with a chamber 43, to receive an enlarged portion 44 of the push pin, whose forward portion projects through a perforation in the spring 33, and is conveniently accessible to the hand of the operator at a point where it may be pressed inwardly. The enlarged portion 44 of the push pin limits its inward motion by engagement with the inner end of the chamber 43, and limits its outward motion by engagement with the spring 33. As a means for preventing the trapping of air in the chamber 43, which would tend to prevent inward motion of the push pin, the enlarged portion 44 of the latter is herein provided with a longitudinal groove 46 to vent said chamber.

During the normal operation of the tool, the push pin 34 is in its outward position, as Shown in Fig. 2, but when it is desired to shorten the stroke of the piston, itinay be pressed inwardly to the position shown in Figs. 3 and 4. IVhen this takes place, the valve can still move rearwardly to its full stroke from mid-position, but its forward movement from mid-position is so limited (see Fig. 4), that only a very small supply of motive fluid passes from the supply chamber 24 through the port 25 to the rear end of the cylinder, and hence the forward stroke of the piston is weakened and shortened, and the reversal of the valve takes place before the piston reaches the normal forward limit of its stroke. As a result, the piston is reeiprocated with reduced amplitude in its cylinder, and does not strike the drillbit; but meantime, pressure Huid is supplied in a lll) practically continuous stream by way of the piston chamber to the drill-bit to clear the hole of its cuttings; while, at the same time, f

ply releasing the push pin, thus permittingl the valve to work its full stroke.

While I have herein shown and described one specific form or embodiment of my invention for illustrative purposes, and have disclosed and discussed in detail the construction and arrangement incidental to one specific application thereof, it is to be understood that the invention is limited neither to the mere details or relative arrangement of parts, nor to its specific embodiment herein shown, but that extensive deviations from the illustrated form or embodiment of the invention may be made, without departing from the principles thereof.

Having thus described one embodiment of my invention, what I claim and desire by Letters Patent to secure is l. In a percussive tool, a cylinder, a percussive piston therein, means operated by reciprocation of said piston for effecting rotation of a drill steel, fluid supply and eX- haust means including distributing valve means, fluid supply port means, and fluid distribution. passages alternately but separately brought by said valve means into f communication with said supply port means and adapted to conduct pressure fluid to the opposite faces of the piston, means for controlling movements of said valve means including piston controlled means for subjecting said valve means to pressure variations to eect movements thereof, and means under manual control and movable between positions respectively wherein it does not adect said valve means and wherein it coacts with said valve means to decrease the rate of flow of fluid past said valve means to one end of said cylinder whereby the path of reciprocation of the piston is limited but steel rotation is maintained.

2. ln combination with a hollow drill steel, a percussive tool comprising a cylinder, a percussive piston in said cylinder, piston controlled steel rotating and cleansing fluid supply means, fluid supply and eX- haust means for said cylinder including distributing vfalve means, fluid supply port means, fluid distribution passages alternately but separately brought by said valve means into communication with said supply port means and adapted to conduct pressure luid to the opposite faces of the piston, means for controlling movements of said valve means including piston controlled means for subjecting said valve means to pressure variations, and means under manual control and movable between positions respectively wherein it does not affect said valve means and wherein it coacts with said valve means to decrease the rate of flow of fluid past said valve means to one end of said cylinder, whereby the path of reciprocation of the piston is limited but steel rotation and cleansing fluid supply are maintained. y y 3. A percussive tool comprising, in combination, a cylinder, a piston working therein, a drill bit percussively actuated by said piston, drill bit rotating mechanism operated by said piston in its reciprocative movements, a piston controlling valve, and manual means to mechanically control the same and effective to decrease the rate of flow of pressure fluid past said valve to stop the percussive action ofsaid piston, while still permitting said fluid to flow at a reduced rate to cause said piston to operate said rotating mechanism, said manual means being substantially instantaneously operable.

4. In a percussive too-l, in conibination, a drilling motor having a cylinder and piston, a hollow drill steel, means for supplying fluid from said cylinder to said hollow drill steel a distributing valve for said motor, and means under manual control for mechanically governing said valve to decrease the rate of flow of pressure fluid past said valve while still permitting said fluid to ilow at a reduced rate to said tool to operate the same with reduced stroke and at a normal rate to said hollow drill steel.

5. A. percussive tool comprising, in combination, a fluid supply connection, a cylinder, a piston reciprocable therein, a hollow drill steel arranged for percussive actuation by said piston, conduit means for supplying pressure fluid from one end of said cylinder to said drill steel, drill steel rotating mechanism operated by said piston in its reciprocative movements, a distributing valve alternately connecting the opposite ends of said cylinder with said fluid supply connection, and means under manual control for decreasing the rate of flow of pressure fluid past said valve when the latter is connecting the rearward end of said cylinder with the fluid supply connection whereby the percussive action of the piston is discontinued, while still permitting fluid to flow to the first named end thereof at undiminished rate when the latter is connected by said valve with the source of fluid supply to cause said piston to operate said rotating mechanism and to maintain an uninterrupted fluid flow through said hollow drill steel.

6; In a percussive tool, a hollow drill steel, a reciprocable pressure fluid operated distributing` valve controlling the flow therethrough, and reciprocable coaXially disposed means under manual control for limiting the movement of said valve while permittingl the same to operate to maintain an unreduced fluid flow through said drill steel. 7. In a percussive tool, a hollow drill steel, a pressure fluid operated distributing valve, reciprocable, coaxially disposed means under manual control for lin'iiting the movement of the valve to less than normal while permitting thesame to operate, and percussive means controlled by said valve and provided with means adapted to form a communication between the motive fluid supply and said drill steel whereby to supp-ly cleansing fluid to the latter.

8. In a percussi ve tool, a hollow drill steel, a. reciprocable pressure fluid operated distributing valve, means under manual control and engageable with said valve for limiting the movement ofthe valve to less than normal while permitting the same to operate to cause. the opera-tion of the tool with a reduced amplitude of movement, and means controlled by said valve and operative to form a communica-tion between the motive fluid supply and said drill steel whereby the latter' may be supplied with cleansing fluid.

9. In a percussive tool, a work piston, a piston chamber, a pressure fluid operated piston controlling valve adapted when moved in opposite directions from its midposition to connect opposite sides of said piston with a source of fluid pressure, and means under manual control comprising a push button movable into the path of said valve for limiting the movement thereof' in one direction from itsk mid-position to less 4 than normal while still permitting its normal movement in the opposite direction from mid-position.

10. In a percussive tool, a work piston, a piston chamber, a hollow drill steel, means adapted to connect said piston chamber and drill steel, a. pressure fluid operated piston controlling valve, and means under manual control and engageable with said valve for limiting the movement of said valve toy less than normal while permitting the same 'to operate to cause a reduced amplitude. of movement of said piston.

11. A percussive tool comprising, in combination, a cylinder, a piston working'therein, a drill-bit percussively actuated by said piston, drill-bit rotating mechanism operated by said piston in its reciprocative movements, a piston controlling valve, and means engageable with said valve to stop the percussive action ofsaid pistonon the drill-bit while still permitting said piston to operate the rotating mechanism.

12. A percussive tool comprising, in combination, a cylinder, a piston working therein, apiston controlling valve, a drill-bit percussively actuated by said piston, drill-bit rotating mechanism operated by said piston in its reciprocative movements, and means engageable with said valve. to limit the movementof said valve to less than normal thereby to cause a reduction of the stroke of said piston while permitting the same to operate.

13. A percussive tool comprising, in combination, a cylinder, a piston working therein, a pressure fluid operated piston controlling valve, a drill-bit rotating mechanis-m operated by said piston in its reciprocative movements, and manually operable means engageable with said valve for limiting the movement of said valve from its mid-position toward the end of that movement which causes the forward movement of said piston, while still permitting full movement of said valve in the opposite direction from its midposition.

14. A percussive tool comprising, in combination, a Cylinder, a piston working therein, a hollow drill steel percussively actuated by said piston, conduit means for supplying pressure fluid from the forward end of said cylinder to said drill steel, a pressure fluid operated piston controlling valve, drill steel rotating` mechanism operated by said piston in its reciprocative movements, and manually operable means engageable with said valve for limiting the movement of said valve from its mid-position toward the end of that movement which causes the same to admit fluid to the rear end of said cylinder', while still permitting full movement of said valve in the opposite direction from its midposition, thereby stopping` the percussive action of said piston, While permitting the same to operate said rotating mechanism, and maintaining a constant fluid flow through said drill steel.

15. In a drillingmechanism, in combination, a hollow drill steel and means cooperating therewith comprising a cylinder, a piston reciprocable in said cylinder and adapted to impact said drill steel, drill steel rotating mechanism operated by said piston in its reciprocative movements, a valve for controlling the supply of pressure fluid to opposite ends of said cylinder, means operative `when said piston is at a predetermined distance from one end of said cylinder to connect that end with said hollow drill steel, and manually controlled means engageable at will with said valve to stop the percussive action of said piston while rcausing it to effeet operation of said rotatingmeans and periodically to open said connecting means.

16. In a drilling mechanism, in combination, a hollow drill steel and means cooperating therewith comprising a cylinder, a piston reciprocable in said cylinder and adapted to impact said drill steel, drill rotating mechanism, a valve for controlling the supply of pressure fluid to offect reciprocation of said piston and rotation of said drill steel, piston controlled means for connecting said drill steel with a source of fluid pressure, and manually controlled mea-ns enname to this specification, in the presence of gageable with said valve for effecting distwo subscribing Witnesses continuation of the percussion of said piston on said steel While continuing the operation GEORGE H. GILMAN. 5 of said rotating means and maintaining said Witnesses: l connectingr means in operation. LEE A. KNIGHTS,

In testimony whereof, I have signed my C. H. TIPPING.

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