US2055497A - Valve mechanism for rock drills - Google Patents

Description

Sept. 29, 1936. c. A. HULTQUIST 2,055,49?

VALVE MECHANISM FOR ROCK DRILLS Filed Now 28, 1934 2 Sheets-Sheet l INVENTOR.

6Zar/es A. f/u/famls/ BY Jun/now} ATTORNEY?! 9 9 c; A. HULTQUIST ,4

VALVE MECHANISM FOR ROCK DRILLS Filed Nov. gs, 1954 2 Shets-Sheet 2 V/MM ATTORNEY I: ha/76544. 246 ;21 :152

are!) STATES? FATENT OFFICE-.1

2,055,497 VALVE MECHANISM FOR ROCK DRILLS Charles A. Hultquis't, Los An'gles, Calif, assignor to" Independent Pneumatic Tool (30;, Chicago;

Ill., acorporation of Delaware Application November 28, 1934-, SerialNoi 755,155

10 Claims.

My invention relates to valve mechanisms-for rock drills, and the ob jects of my invention are:

First, to provide a valve mechanism for rock drills which provides a correct distribution of the.- compressed fluid .used in. operating. the tool in order to obtain greater drilling speedwith reduced power consumption; p

Second, to provide a valve mechanism of this class for rock drills so constructed: that more compressed fluid will in its operation to eith be admitted by the valve erendof thecylind'erbor'e at the start of each stroke of the drill hammer than later in the strokes; and

Third, to provide a new an valve and valve chest economical of construction,

(1 novel distributing which is verysimple and eflicientin its action,-

and which will not readily deteriorate or get out of order.

With th ese and other objects in view as willappear hereinafter, my invention consists ofcertain novel features of construction, combination and arrangement of parts and portions as will be hereinafter described in detail and particu-- larly set forth in the appended cl'aims; reference 5 being had to the accompanying drawings and to the characters of reference thereon which form a part of this application, inwhich:

'Figure 1 is a back end view with a portion of the f the rockdrill throttle broken away and in section to facilitate the illustration; 2 islongitudinal sectional line 22 oiFig.'l and ing valve in its re fluid to the rear en tion for drivin ward or working stroke of the head through 3- g the hammer p1 Fig. 3 is a sectional view 3*of Fig. l, and Fig. 4

f the drill on the the-air distributview 0 showing arward position for admitting d of the cylinder bore-in posiston on its for is a fragmentary sectional view on an enlarged scale through 44 of tributing valve in its Fig. 2 andshowing the disforward position for ad mitting fluid to the forward end of the cylinder bore for driving the or return stroke.

Similar characters of hammer piston on its rear reference referto similar Q parts and portions throughout the several views" of the drawings.

As in the convention al rock" drill of this class;

my rock drill is provided with a back head*-5 which operates a thro to difierent positions is held in varied positionsby a ratchet pawlandspring, as shown best in Figs. 1 andB ofthe drawings, whichare conventional and may be'omittedg if desired, without afiecting the operation of my valve mechanism. Screwed into the housing 6" at the opposite end from the throttle handle 8 is: an air inlet spud 9 which is the main air inlet to the; rock drill. The head 5 is also provided 5 with aehole lfl'which is adapted to receive the handle-in the conventional manner for supporting: the drill duringthe drilling operations.

Seated partly in the back head 5 and partly in: the counter bore H of the rear cylinder l2 107' is a conventional ratchet mechanism l3 which consists of the" conventional ratchet ring, pawls, springs and the head of the rifle bar I l, not shown in detail excet the. end of the rifle bar I74. This rifle bar M is provided withhelical 15- flutes whichare adapted to engage helical ridges cut in the rifle nut" |5i which is screwed into. the hammer piston l6; thus providing means for rotating the hammer piston IB- when it travels back and forth m the cylinder I2 that this rotating movement is conveyed to the. chuck driver IT by reason of flutes cut on the hammer extensiom l'8 which engage notches l9 in t'he' chuck drivet N. This in turn rotates the drill steel which" is supported in the chuck driver ll by means ofa hexagon shank H. The back head 5 and f'ronthead 2-2" and the intermediate parts are held in rigid alinement and position by two side bolts 23g shown in Fig. 1 of the drawings, which pass through: lugs in the back head 5 and front head 22 It will be here noted that the structure so far desc'ribed iri detail i's subst'antially' conventional in form of pneumatic rock drills of this" class but-is necessary for combinative' relation-with the valve mechanism described hereinafter.

Mounted inthe counter bore H of the rear cylinder l-Tis' aval've chest 25 and reciprocally mounte'd inthis-v lye chest 25 is-a tubular sliding distributing valve which slides on the bearing 2 6" which bearing ZE-"i'smade integral with the flange 21'- Which is clamped incentral alinement betweenthe rearward end of the valve chest 25 and the ratchet mechanism l'3-in the bore II. The valve'bearing 26- and flange 21 are hollow 4-5 and therifle ban l4 extends through the valve bearing-"ifiandfl'ange 21$ The'valve' chest 25 is provided with a central fluid supply groove 28' and-with fluid reservoir chambers 29 and 30 on oppositesides thereo I bores-in the'ridges 31 and 32 ar e' o'fl equal dimen sion's, while thebore in the ridge 33- is larger in' diameter tha'nthe bores in theridges 3| and 3.2,. and the bore in the ri'dge 34 is larger than the bore inthe ridge 33*; A counter 'bore 35 in the 55 It will be noted f. The" diameters of the the front end 36 of the cylinder bore through inlet port 31. The central supply groove communicates with a throttle valve 1 and supply chamber 38 through ports 39, shown best in Fig. 2 of the drawings.

' The distributing valve 24 has four flanges from its rear end forwardly, designated 4|), 4|, 42 and 43, shown best in Fig. 4 of the drawings. The flanges 3| and 42 are of equal dimensions but smaller in diameter than the bores of the ridges 33 and 34 in which they operate, thus leaving spaces 4-2 and 45 between the flanges 4| and 42 and ridges 33 and 34 which are constantly open for the flow of fluid into the chambers 29 and 33. The spaces 44 and 45 control the amount of fluid required for driving the hammer piston IS on its forward and rearward strokes. The two flanges 4B and 43 are of equal dimensions but thicker and of heavier construction than the flanges 4| and 42 because they .serve in conjunction with the ridges 3| and 32 as stops for limiting the travel of the distributing valve 24. The flanges 40 and 43 are spaced on the valve in relation to the inner face of the ridges 3| and 32 to provide the valve with a very short travel and against which they seat intermittently and make an airtight joint. These flanges 4|] and 43 are smaller in diameter than the flanges 4| and 42, therefore the flanges 4| and 42 have. a larger pressure area on their outer faces 45 and Lil than the flanges 45 and 43 have on their inner faces 48 and 49. The difference in the diameters of the constrictions in the valve cheston opposite sides of the central inlet in the valve chest which results in a different space at the opposite sides of the inlet in cooperation with the resultant varying static pressure provides means for facilitating the starting operation of the tool and also accelerates the movement of the valve while in operation.

It will behere noted that no confusion can occur in assembling this valve mechanism because the flanges M and 42 are spaced equally from the center of the valve 24 and are of the same dimensions as the flanges 30 and 43, although smaller in diameter than the flanges 4| and 42, are of equal dimensions and spaced equally from the middle of the valve. Therefore, it will be seen that the valve 24 will operate equally as well if turned end for end, or reversed in position.

The operation of my valve mechanism is as follows: Referring generally to Fig. 2 of the drawings, fluid under pressure enters the back head5 through the inlet spud 9, shown in Figs. l'and l of'the drawings, into the hollow portion 50 of the throttle valve 7. Thence through inlet port 5|. inthe throttle valve 1 and the port 52 in the. back head 5 and into the chamber 38. Thence through the supply ports 39 into the central supply groove'28 of the valve chest 25. Fromthere it is distributed by the distributing valve 24. It will be noted thatthe valve 24 is shown in its rearward position in Fig. 2 of the drawings and the fluid flows through the spaces 44 and 45 into the'reserve chambers 29 and 3|], the flange lljbeing seated against the inner side of the ridge 3|. From the chamber 36 thefluid flows throughrthe opening 53 into the rear end 54 of the cylinder bore where it operates the hammer piston I6 driving it forward on its working stroke. The fluid pressure against the outer side of theflange 43 and the end face 55 of the valve. holds the valve in its rearwardpositiom 2,055,497 rear end of the valve chest 25 communicates with as shown in Fig. 2 of the drawings. In its forward travel the hammer piston it has passed over and closed the exhaust port 56, shown in Fig. 2 of the drawings, and is now compressing fluid in the front end 36 of the cylinder bore. This compressed fluid flows through the port 31 into the counter bore of the valve chest 25 where it acts on the rear end 5? and pressure area 58 of the valve 24. As the hammer piston l6 continues on its forward or working stroke the exhaust port 55 is uncovered at the rear of the hammer piston l5 and exhaust is now taking place in the rear end 54 of the cylinder bore.

As the pressure against the end face 55 and outer side of the flange 53 of the valve 24 is lessened, the pressure created against the rear end 51 and pressure area 58 moves the valve to its forward position, as shown in Fig. 4 of the drawings.

The shifting of the valve is arranged by applicants construction and mode of operation to occur a moment before the hammer extension |8 strikes the end of the drill shank 2|. The fluid is now flowing through passages 44 and 59 into the counter bore 35, thence through the cylinder port 31 into the forward'end 36 of the cylinder bore for driving the hammer piston l6 rearwardly. On its return stroke the hammer piston l6 passes over and closes the exhaust port 56 which causes compression in the rear end 54 of the cylinder bore. As the hammer piston I6 continues on its rearward stroke it passes completely over the exhaust port 56. Exhaust is now taking place in the front end 36 of the cylinder bore. As the pressure diminishes against the end face 5? and outer side of the flange of the distributing valve 24, the pressure caused in the rear cylinder bore 55 acting on the end face 55 and the pressure area 60 moves the valve to its rearward position and the hammer piston 6 will again start on its forward stroke.

The above-described operation of the different parts will continue as long as fluid under pressure flows into the groove 28 of the chest 25.

Because of the fluid reserve in the chambers 29 and 30, the fluid supplied to drive the hammer piston I5 forwardly and rearwardly is greater at the initial start of the stroke than at any other time. This provides a quick start for the hammer piston Hi from each end of the cylinder bore which increases the speed of the hammer piston and more work is accomplished than would be possible by a valve mechanism where there are no reserve chambers.

.Though I have shown and described a particular construction, combination and arrangement of parts and portions, I do not wish to be limited to this particular construction, combination and arrangement but desire to include in the scope of my invention the construction, combination and arrangement substantially as set forth in the appended claims.

Having thus described my invention, what I claim as newand desire to secure by Letters Patent is:

1. In a valve mechanism for rock drills, a cylindrical bearing, a hollow tubular valve member slidable thereon provided with two relatively large diameter flanges in spaced relation at the middle thereof and with two smaller diameter flanges one near each end of said valve member in spaced relation to the first mentioned flanges, a valve chest surrounding said valve member, and constrictionsoverhanging the end flanges of said valve member and adapted to be engaged by" said flanges with the backward and forward movement of said valve member, and a pair of in operative relation with the middle flanges of said valve member, one of said constrictions having a larger diameter bore than the other; and afluid conducting channel between said intermediate constrictions in said valve chest.

2; In a valve mechanism for'rock drills, a cylindrical bearing, a hollow tubular valvemem ber slidable thereon provided with two relatively large diameter flanges in spaced relation at the middle thereof and with two smaller diameter flanges one near eachend of said valve-member in spaced relation to theflrst mentioned flanges, a valve chest surrounding said valve member, and constrictions overhanging the end flanges of said valvemember and adapted to be engaged by said flanges with the backward and forward movement of said valve member, a pair of constrictions in said valve chest intermediate the end constrictions in spaced relation to each other in operative relation with the middle flanges of said valve member, one of said constrictions having a larger diameter bore than the other, a fluid conducting channel between said intermediate constrictions in said valve chest, and a counter bore at the rearward end of said valve chest in communication therewith.

3. In a valve mechanism for rock drills, a cylindrical bearing, a hollow tubular valve member slidable thereon provided with two relatively large diameter flanges in spaced relation at the middle thereof and with two smaller diameter flanges one near each end of said valve member in spaced relation to the first mentioned flanges, a valve chest surrounding said valve member, and constrictions overhanging the end flanges of said valve member and adapted to be engaged by said flanges with the backward and forward movement of said valve member, and a pair of constrictions in said valve chest intermediate the end constrictions in spaced relation to each other in operative relation with the middle flanges of said valve member, one of said constrictions having a larger diameter bore than the other, and a fluid conducting channel between said intermediate constrictions in said valve chest, said chest provided with two fluid chambers formed between the intermediate constrictions and the outer constrictions of said valve chest.

4. In a valve mechanism for rock drills, a cylindrical bearing, a hollow tubular valve member slidable thereon provided with two relatively large diameter flanges in spaced relation at the middle thereof and with two smaller diameter flanges one near each end of said valve member in spaced relation to the first mentioned flanges, a valve chest surrounding said valve member, and constrictions overhanging the end flanges of said valve member and adapted to be engaged by said flanges with the backward and forward move ment of said valve member, a pair of constrictions in said valve chest intermediate the end constrictions in spaced relation to each other in operative relation with the middle flanges of said valve member, one of said constrictions having a larger diameter bore than the other, a fluid conducting channel between said intermediate constrictions in said valve chest, and a counter bore at the rearward end of said valve chest formed by one of said constrictions, said chest provided with two fluid chambers formed between: the: intermediate constrictions and the outer constrictions of said valve chest 5.4 In a valve mechanism for rock drills, the. combination with a tubular flanged sliding valve of an annulartubular valve chest provided with two spa'cedconstrictions extending inwardly intermediate'the ends of said valve chest and leaving a fluid intake channel between said constrictions; the bores of said constrictions being of unequal diameter, and also providecl with two inwardly extending outer constrictions spaced from said middle constrictions and leaving. annular fluid res ervoir' chambers. therebetween.

6i In: a valve mechanism for rock drills, the combination with-.a tubular flanged sliding distributing valvefof an annular tubular valve chest provided with two spacedconstrictions extending inwardly intermediate the ends of said valve chest 'and' 'leaving a fluid intake channel between said constrictions, the bores of said constrictions being of unequal diameter, and also provided with two inwardly extending outer constrictions spaced from said middle constrictions and leaving annular fluid reservoir chambers therebetween, the bores of said outer constrictions being of equal diameter.

7. In a valve mechanism for rock drills, the combination with a tubular flanged sliding distributing valve of an annular tubular valve chest provided with two spaced constrictions extending inwardly intermediate the ends of said valve chest and leaving a fluid intake channel between said constrictions, the bores of said constrictions being of unequal diameter, and also provided with two inwardly extending outer constrictions spaced from said middle constrictions and leaving annular fluid reservoir chambers therebetween, the bores of said outer constrictions being of equal diameter, said valve chest also provided with a counter bore between the rear outer constrictions and the end of said valve chest.

8. In a valve mechanism for rock drills, an annular tubular valve chest provided with two spaced constrictions extending inwardly intermediate the ends of said valve chest and leaving a fluid intake channel between said constrictions, the bores of said constrictions being of unequal diameter, also provided with two inwardly extending outer constrictions spaced from said middle constrictions and leaving annular fluid reservoir chambers therebetween, the bores of said outer constrictions being of equal diameter, and a tubular valve slidably mounted in said valve chest provided with outer flanges near the opposite ends of said valve of a diameter adapted to engage the inner side walls of said outer constrictions of said valve chest and arranged to provide clearance for slight shiftable movement between said flanges and said outer constrictions.

9. In a valve mechanism for rock drills, an annular tubular valve chest provided with two spaced constrictions extending inwardly intermediate the ends of said valve chest and leaving a fluid intake channel between said constrictions, the bores of said constrictions being of unequal diameter, also provided with two inwardly extending outer constrictions spaced from said middle constrictions and leaving annular fluid reservoir chambers therebetween, the bores of said outer constrictions being of equal diameter, and a tubular valve slidably mounted in said valve chest provided with outer flanges near the opposite ends of said valve of a diameter adapted to engage the inner side walls of said outer constrictions of said valve chest and arranged to provide clearance for slight shiftable movement between said flanges and said outer constrictions, said valve also provided with a pair of spaced flanges on the middle portion of said valve positioned to operate in the bores of said middle constrictions of said valve chest, said flanges being of equal diameter whereby the spaces between said flanges and middle' constrictions are varied.

'10. In a valve mechanism for rock drills, an annular tubular valve chest provided with two spaced constrictions extending inwardly intermediate the ends of said valve chest and leaving a fluid intake channel between said constrictions, the bores V of said constrictions being of unequal diameter,

also provided with two inwardly extending outer constrictions spaced from said middle constrictions and leaving annular fluid reservoir chambers therebetween, the bores of said outer constrictions being of equal diameter, a tubular valve slidably mounted in said valve chest provided with outer flanges near the opposite ends of said 1 valve of a diameter adapted to engage the inner side walls of said outer constrictions of said valve chest and arranged to provide clearance for slight shiftable movement between said flanges and said outer constrictions, said valve also provided with a pair of spaced flanges on the middle portion of said valve positioned to operate in the bores of said middle constrictions of said valve chest, said flanges being of equal diameter whereby the spaces between said flanges and middle constrictions are varied, and said valve provided with extended annular end portions spaced from the inner side of the bore of said outer constrictions to provide pressure spaces for the sides of the flanges of said valve. 7

CHARLES A. HULTQUIST.

Images