US1803107A - Pressure-fluid motor - Google Patents

Description

April 28, 1931. E. G. GARTIN PRESSURE FLUID MOTOR Original Filed June 4, 1927 Patented Apr. 28, 1931 unrrsn STATES PATENT {OFFICE ELMER G. GARTIN, F CLAREMONT, NEW HAMPSHIRE, ASSIGNOR- TO SULLIVAN IMA- CHINERY COMPANY, A CORPORATION OF MASSACHUSETTS PRESSURE-FLUID MOTOR Application filed June 4, 1927, Serial No. 196,430.- Renewed. December 26, 1929.

This invention relates to pressure fluid motors and more particularly to pressure fluid motors of the hammer type.

An object of this invention is to provide an improved pressure fluid. motor. A further object is to provide an improved pressure fluid motor of the hammer piston type wherein pressure fluid is supplied continuously to the front pressure area on the hammer piston and supplied periodically to the rear pressure area on the piston under the control of an automatic piston-controlled fluid distribution valve. A further object is to provide an improved pressure fluid motor wherein the fluid distribution means is extremely simplified and the power and efficiency of the motor is materially increased. These and other objects will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In this drawing,

Fig. 1 is a central longitudinally extending 25 sectional view illustrating the improved pres sure fluid motor.

Fig. 2 is an enlarged sectional view similar to Fig. 1 showing the valve and piston in different positions. a

as Fig. 3 is a transverse sectional view taken on line 33 of Fig. 1.

In this illustrative construction there is shown a pressure fluid motor-of the hammer type comprising a cylinder 1 having abore 2 in which a hammer piston 3 is reciprocably mounted. The hammer piston 3 hasformed integral therewith and projecting forwardly therefrom a striking bar 4 movably mounted in a bore 5 formed Within a front buffer ring 6. As shown, the cylinder 1 is provided with a forwardly projecting sleeve-like portion 7 having a bore 8 in which the buffer ring 6 is positioned. The rear end of the buffer ring 6 isseated against a shoulder 9 formed at the junction of the cylinder bore 2 and the bore 8, this buffer ring being held in position by a front chuck housing 10 projecting within the bore 8 and abutting against the forward end of' the buffer ring. The chuck housing 10 carries at the forward combined head, block and valve chest 15 while engaging the outer surface of this head block is arear plate 16. The chuck housing, buffer ring, cylinder, rear head block and rear plate are held in assembled relation in any suitable and convenient manner.

In the improved construction the valve chest 15 has formed therein alined bores 17 and 18 of difle-rent diameters and preferably having their axes'alined with the longitudinal axis of the motor cylinder. Reciprocably mounted within the bores 17 and 18 is an automatic piston-controlled fluid distribution valve 19, herein preferably of the three spool differential type. The valve 19 is pro vided with a large rear end spool 20 fitting the bore l7and a central spool 21 and a front end spool 22 bothfitting the bore 18. As K shown, the spools 20, 21 and 22 are connected by reduced portions 23 and 24. The outer end of the bore 17 is closed by the rear plate 16. Formed in the valve chest 15 at the forward end of the bore 17 and at the rear end of the bore 18 respectively are annular grooves or recesses 25 and 26, while located intermediate these grooves is a similar groove 27. Fluid pressure is adapted to be supplied to the motor through a longitudinal passage 28 communicating at 29 withthe cylinder bore 2 at the forward end thereof.

eating with the cylinder bore 2 intermediate the ends thereof as by a port 32 is a longitudinally extending throwing passage 33 which communicates with the bore 17 adjacent the rear end thereof. Extending centrally through the valve 19 and communicating with the bore 17 is a restricted leak passage 34: which in turn communicates through -a lateral port 35 with the bore 18 at a point intermediate thespools 21 and In the operation of the improved pressure fluid motor it will be assumed that the hammer piston 3 is in the position shown in Fig. l and is about to be driven forwardly to effect its working stroke. At this time, pressure fl'ui'd flows from the passage 28 through the lateral passage 29 into the annular recess 25, through the bore 18, the annular recess 2'7 and thence through the passages 31 to the rear end of the cylinder b'ore Simultaneously, pressure fluid flows through the supply passage 28 through the lateral port 29 to the fo rw'arden'd 'of the cylinder bore, the fluid flowing from the forward end 'of the cylinder bore through the port 32 and throwing passage 33 to the bore 17, and as a result the valve 1 9 is held in its forward position shown in Fig. .1. Due to the rel'ativelylarger pressure area on the rear surface of the hammer piston the pressure acting on the relatively small front pressure area-of the piston is overcome and consequently the hammer piston is driven forwardly. During this forward stroke of the piston the port32 is cut o l"? by the piston head and the pressure within the bore 17 at the rear end of the valve leaks out through the passage 84, port 35, through. the radial exhaust passages directly to atmosphere. Continuous pressure acting on the forward surface of the relatively large spool 20 causes the valve to be thrown rearwardly to the position shown in Fig. The pistoncontinues its forward travel due to the expansive action of the pressure fluid and momentum and delivers a blow to the shank of the drill steel 12. \Vhen the valve assumes the position shown in Fig. 2 the pressure fluid in the rear end of the cylinder bore is exhausted to atmosphere through the passages 31, annular recess '27, through the bore 18, annular recess 26 and passages -30 to atmosphere. The hammer piston is then driven rearwa rdly by the pressure fluid within the forward end of the cylinder bore acting continuously on the forward pressure area of the hammer piston. As the piston 3 moves rearwardly thoport is again uncovered and pressure fluid is admitted through the throwing passage 35 and the valve is again thrown forwardly to'the position shown in Fig. 1 and thiscycle of operation is repeated throughout the normal operation of the motor. v H

As a result of tl "s invention an improved pressure fluid motor isp'rovided wherein the pressure fluid acts continuously on the forward pressure area of the piston while the pressure fluid is periodically supplied to act on the relatively large pressure area on the piston under the control of an automatic pis ton controlled valve. It Will further be noted that an improved pressure fluid motor is provided wherein the fluid distribution means is exceedingly simplified and wherein the power and efficiency of the motor is materially increased. These and other advantages of this invention will be clearly apparent to those skilled in this art.

Vhile I have in this application specifically described one form which my invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

l. A pressure fluid motor comprising a cylinder, a. piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a passage for constantly admitting pressure fluid to the front end of said piston, means for controlling the supply and exhaust of fluid for the rear end of said piston comprising a reciprocable differential fluid distributon valve having a large spool and a reduced spool, a pas sage controlled by said piston for admitting pressure fluid from said cylinder to one surface of said large spool for throwing said valve in one direction to connect the rear end of said piston through the valve chest directly with the rear end of said first mentioned passage, and a passage for constantly admitting pressure fluid to the opposite surface of said large spool to throw said valve in the opposite direction to connect the rear end or said piston with the exhaust.

2. A pressure fluid motor comprising a cylinder. a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including means for constantly admitting pressure fluid to the front end of said piston,'means for control ling the supply and exhaust of fluid for the rear end of said piston comprising a reciprocable difl'erential fluid distribution valve having a large spool and a reduced spool. a passage controlled by said piston for admitting pressure fluidfrom said cylinder to one surface of said large spool for throwing said valve in one direction to connect the rear end of said piston with'the fluid supply, a passage for constantly admitting pressure fluid to the opposite surface of said large spool to throw said valve in the opposite direction to connect the rear end 'ofsai-d piston with the exhaust. and a leak passage formed in said valve for c'oii'necting the pressure area at the Ill) rear end of said large spool continuously with the exhaust. Y

3. A pressure fluid motor comprising a surface of said large spool for throwing said valve in one direction, supply and exhaust passages controlled by said central spool, and means for constantly admitting pressure fluid to the opposite surface of said large spool for throwing the valve in the opposite direction.

4. In a drilling apparatus, a pressure fluid actuated percussive motor, a piston reciprocable therein, a striking bar projecting from the piston through one end of the cylinder,

and fluid distribution means for actuating said pistonincluding means for continuously admitting fluid pressure to the forward end of the cylinder to act on thereduced area of the piston around the striking bar, a valve for controlling the supply and exhaust of fluid to and from the rear end of the cylinder,

said valve having a reduced spool for controlling the communication between the cylinder and the supply and exhaust, said valve also having a larger spool presenting an unbalanced area continuously subjected to fluid actuated percussive motor having a cyllnder, a piston head reciprocable therein, a striking supply pressure'tending to hold the valve in position for opening the rear end of the cylinder to exhaust and means controlled by the piston for intermittently throwing the valve to its other position for admitting pressure fluid to the rear end of the cylinder.

5. In a drilling apparatus, a pressure flllld actuated percussive motor, a piston reciprocable therein, a striking bar projecting from the piston through one end of the cylinder, and fluid distribution means foractuating said piston including means for continuously admitting fluid pressure to the forward end of the cylinder to act on the reduced area of the piston around the striking bar, a valve for controlling the supply and exhaust of fluid from the rear end of the cylinder, said valve having a central spool for alternately establishing communication of the rear end of the cylinder with the supply and exhaust, a

larger spool on one side of said central spool,

said spools having adjacent opposed surfaces presenting a differential area to the action of fluid supply pressure tending to hold the valve in one extreme position for openlng the rear end of the cylinder to exhaust, and a throwing passage controlled by the piston for admitting pressure fluid from the cylinder to the opposite side of said larger spool for throwing the valve to its other extreme posi tion foreflecting admission to the rear end of the cylinder, and guiding means on said valve on the opposite side of said central spool from the larger spool.

6. In a drilling apparatus, a pressure fluid actuated percussive motor, a piston reciprocable therein, a striking bar projecting from the piston through one end of the cylinder,

and fluid distribution means for actuating said pistonincluding means for continuously admitting fluid pressure to the forward end of; the cylinder to act on the reduced area of the piston around the striking bar, a valve for controlling the supply and exhaust of fluid'from therear end of the cylinder, said valve having a central spool for alternately establishing communication of the rear end of the cylinder with the supply and exhaust, a larger spool on one side of said central spool, said spoolspresenting a diflerential area to the action of fluid supply pressure tending to holdthe valve. in one extreme position, a

throwing passage controlled by the piston for admitting pressure-fluid from the cylinder to the opposite side of said 1 r er spool for throwing the valve to its other extreme position, and guiding means on said valvejon the opposite side of said central spool from the larger spool, said guiding meansconstituting a third spool of the same size as the central spool, anda'leak passage for relieving the throwing pressure on said larger spool when said throwing passage is closed to said cylinder.

7. In a drilling apparatus, a fluid pressure bar projecting from said head, and fluid distribution means for. effecting reciprocation of said piston including a valve having large and small spools, a fluid supply inlet, a passage for conducting live fluid to the front end of said piston, a passage controlled by the smaller spool whereby live pressure fluid communicates with the rear end of said piston, an exhaust passage, a passage leading from said cylinder and controlled by said piston head, said piston controlled passage being adapted to have communication with said exhaust passage through said valve mechanism and to conduct live pressure fluid to one side of the larger spool to move said valve.

The combination set forth in claim 7 further characterized in that a transverse surface of said valveis constantly subjected to live fluid pressure.

9. The combination set forth in claim 7 further characterized in that a transverse surface of-said valve is constantly subjected to live pressure fluid, and means are provided whereby the actuating fluid from one end of said cylinder is directed to said exhaust passage by the smaller spool.

10. A pressi'n-e fluid motor comprising a cylinder, a piston reciproc'able therein, and

fluid distributionmeans for efii'ecti n g reciprocation of said piston including an inlet passage, a passage for admitting pressure fluid to the front end of said piston from said inlet, means for controlling the su ply of iiuid for and exhaust of fluid from the rear end of said piston comprising areciprocable differential fluid distribution valve having a large spool and a reduced spool, a passage controlled by said piston for admitting pressure fluid from said cylinder to one surface of said large spool for throwing said valve in one direction and to connect the rear end of said piston through the valve chest directly with the rear end of said first mentioned passage, and a passage for constantly admit ting pressure fluid to the opposite surface of said large spool for throwing said valve in the opposite direction to connect the rear end of said piston with the exhaust.

llfA pressure fluid motor comprising a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including an inlet, means for controlling the supply and exhaust of fluid for the rear end of said piston comprising a reciprocabl'e differential fluid distribution valve having a. large spool and a reduced spool, a'pa'ssa'ge controlled by said "piston for admitting pressure fluid from said cylinder to one surface of send large spool for throwing said valve in one direction to connect one end. of said piston with the fluid supply, a passage for constantly admitting pressure fluid to the opposite surface of said large spool to throw said valve in the opposite direction to connect the rear end of said piston to the exhaust, and a leak passage for connecting the pressure area at the rear end of said large spool with the exhaust.

In testimony whereof I afiix my signature.

ELMER G. GARTIN.

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