US1020619A

US1020619A - Valve mechanism for pneumatic tools.

Info

Publication number: US1020619A
Application number: US5793?210A
Authority: US
Inventors: Vincent J O'brien; Romeo C Awkerman
Original assignee: STANDARD ROCK DRILL Co
Current assignee: STANDARD ROCK DRILL Co
Publication date: 1912-03-19
Anticipated expiration: 1929-03-19

Description

V. J. OBRIEN & R. O. AWKERMAN.

VALVE MECHANISM FOR. PNEUMATIC TOOLS.

APPLICATION FILED AUG. 27, 1910.

Patented Mar. 19, 1912.

3 SHEETS-SHEET 1.

iyg (:1 "001mg V. J. OBRIEN & R. C. AWKERMAN. VALVE MECHANISM FOR PNEUMATIC TOOLS. APPLIOATION FILM; AUG 27, 1910.

1,020,6 l 9, Patented Mar. 19, 1912.

.Qvi l neoocs,

, warm u'uawfo I G HOT/"Cid 'throt tle valve mechanism ITE STATES sum-0mm n VINCENT J. O'BRIEN AND nor/IE0 c. AWKERMAN. or DENVER. COLORADO,- ASSIGNORS TO THE STANDARD ROCK TION OF COLORADO.

DRILL COMPANY. OF DENVER. COIZORADO, A CORPORA- VALVE MECHANISM FOR PNEUMA-rrc room.

Specification or Letters Patent.

Patented Mar. 19, 1912.

Application filed August 27. 1910, Serial No. 579.332

To all whom it may concern:

Be it known that we. Vrxcn'x'rJ- OBlnex a-m'l Rom-1o. (l. .hvuuznuax, citizens of the lnited States. residing in the city and county of Denver and State of Cdlorado, have invented certain new and useful T mprovemeats in Valve .\lechanisin"for Pneumatic Tools: and we do declare the following to he a fulllclear, and exact description ofth'e invention. such as will enable others skilled in the art-'to which it. appertains to make and use the same; reference being had to the :u-conipanviug drawings. and to the letters and figures, of reference 'niarked thereon, which t'ci n a part of this specification. j

Our invention relates"generally speaking ha-nnner.- This is a very important feature when itisdesired to run the drill slowly or to reciprocate the hammer at a redu'c'ed speed as when the material to be drilled is coinp u'atively soft, and under such circumstances it is exceedingly desirable that the feed bar be actuated by the motive fluid at a pressure reduced to correspond with that which is delivered to'thc drill'cylinder.

Another 'featui-e of our improved construction" of valve mechanism is that it allows a portion" of the motive. fluidwhich has been used to propel the hammer on its .forwardgmovement, to escape directly to the atmosphere. In explanation of this feature itfma'y be said that'it is quite common in to lH'lPIOYOlllQlllS in valvemeeh'anism tor: lllflCl'llIlQQfllllS class-to employ hollowcypneumatic tools, but more specifically to for iOOlsUfilllS character in which a feed bar is employed for holding the steel of a hammer drill against the rock.

One object of the invention is to providefia 't'onstruction whereby' it becomes practicable to supply the feed bar casing with motive fluid under pressure equal to that which is employed to operate the hammer which reciprocates in the cyllnde r of the machine.

In the construction common to this class of tools, the pressaire of the motive fluid which acts upon the piston of the feed bar, is

much greater thanthat whiclr'acts upon the hammer for reciprocating the latter,'when the hammer is operating slowly. On this account the drill bitin the ordinary construction heretofore in vogue is'held against the rock with much greater pressure than is desirable, under the circumstances stated. In our improved construction the motive fluid which fed to the casing of the feed bar and to the drill cylinder, is controlled in such a manner that it passes to a chamber interposed between-the throttle valve' and the cylinder valve under only such pressure as is necessary to reciprocate the hammer at motive fluid passin from this chamber simultaneously to the fee bar casing and-the drill cylinder. Hencethe delivered to. the feedbar passes to the cylinder for, reciprocating the lindrical valves having differential pressure areas attheir opposite extremities, l the smaller o'li which is constantly exposed to motive fluid'pressurc, and the larger interni'it'tently e'Xposedthere-toin some stylesof these'tools the motive fluid which has been'nsed to pro pel the hammer on its for ward movementiilsxtill used as motive fluid while passing to the atmosphere in so far as it exerts a pressure against the larger area of thevalve sufiicient to overcome the constant pressure on the smaller area. 'We have. demonstrated inactual practice that the speed of a machineequipped with the above'style-oi valve, can be increased ten per cent. or m re by the use of an auxiliary exhaust controlled'by our improved throttle valve. The reason is that the auxiliary exhaust results in a sudden weakening of presssure at theprecise time when it is needed, namely; when he hammer is stationary at the end'of itsf tirward stroke. and about to start on itsretn'iyn trip.- Int-his event after the hammer hashioved a short portion ofits return trip,'it covers the auxiliary exhaust portfso that'-the'etlect of motive fluid passii'i'g to the atmosphere from the larger areax of the cylinder valve is not changed; The I ,r'eason-th't the auxiliary exhaust of the aforesaid character must be controlled. by the thr0ttl ;valve,' is-that the auxiliary e15} i haust musthot occurunt'rl the machine has re ched almost. its maxim m s r Iii exhaust b gll edj o e ters isestlr o, the

60 1n the valve-block 15. The smaller extrem-.

atmosphere the machine will not work well whilerunning at a slow speed, hence the nerecess 19 which is in communication with a conduit 20 which screwed nto the valve cessity for controlling it by 'theuse of the block as shown at 21 and registers with the throttle-valve so thatthe auxiliary exhaust is only employed whenthe machine is .running-"at practically/its maximum speed. I

Having briefly outlined our improved connalcd; This conduit supplies the motive fiunl for operatmg the reciprocating hammer aswell as that which acts upon the feed Sta-notion, we will proe edZt d s ib the bar for automatically maintaining the drill trated'an em hodiment thereof.

In this drawing: Figure 1 1s a fragmentary section taken through a hammer drill equipped with our improved throttle valve construct on, a part of the hammer cylinder chamber 251:0 a supply chamber 28 formed The valve block is provided with three ports 22, '23 and 2 re 25 to the chamber 12 in which the feed bar reciprocates; and also with

passages

26 and 27, the passage 26 leading from the valve and a part of the feed bar constructio being in the valve block adjacent the valve mechaoff from the feed bar and the hammer cylinder, the feed bar chamber beingin communication withqthe' atmosphere;, for exhaust-purp'oses. Fig. .2 is a sim lar v ew llustrated. In this view the throttle valve n sm] and communicating with passages 29 is so adjusted that the motive fluid is' cut formed in the casing 30 and inclosing the valve mechanism 7. The passage 27 also leads from the valve chamber 251a) the sup-' ply chamber 28. This chamber-28 enables us to obtain a number of advantages in the opening in which the valve piece'is' jour- 'specti-vely leading from the valve chamber a showing'the throttleHvalve-in a: diflerent' operationof the machine. Among these are position, namely, that in which the motive the follow ng: Since the motive fluid passes fluid is delivered to'the feed bar .chamber,. from this chamber toboth the engine and but cut oif from the hammer chamber Fig.

to a chamber interposed between the cyl1nder valve and the throttle valve, the-motive v fluid passing from the said chamber to the cylinder chamber andfeed her 1' chamber 'in the motive fluid in such a manner that no pose; Figs. 4and 5' are 1 sections taken feed bar casing, the pressure must be the ,3 is a similar view-in-which the motive fluid. samein both and will always be proportionis cutoff from direct communication with;

m a the feed bar casing to the requirement for holding-the drill against the rock. This feature has been already mentioned. lhis 1 chamber 28 also makes it practicable to andle the dirt and foreign matter contained harm results to the delicate valve mechanism 'of the engine, since the dirt contained through the throttle -valve mechanism onin the motive fluid passes to the engine at lines 4- 4 and 5-5 respectivelyfof Fi'gia fi2.'

Figs. 6 and 7 are sections taken on the and is much less injurious to that part than 7-7 Fig. 2, showing the throttle valvezn when it is allowed to accumulate in the feed two difi'erent positions. Fig. 8'is a sect-ion bar casing inwhich latter event it is extaken through a hammer drill cutting the oeedingly injurious tothe feed bar'mech'athrottle valve mechanism, the parts, being nism at all times and to the valve mechanism shown in the position illustrated in Fig. 7, of the engine whenever the position of the exhaust. Y Y

- to permit the employment of theau iliary engine is changed so that the feed bar (as ing is above, whereby the accumulation of The same reference characters indicate the dirt and foreigmparticles of matter is alsame partspin all the'views.

Let the'numeral 5 desi ate the cylinder;

tively large quantities.- Furthermore'this 6 the hammer; 7 the va ve mechanism for chamber enables us to obtain the most speedy cont-rollin the supplygi and exhaust to and andsensitwe coactiorr between the pressure from the ammer c'ylinder; 8 the casing m which the piston 9 of ar feed bar 10 is mounted to reciprocate, Interposed between the valve and inthe teed bar and t e speed of the motor;

he'consuming capacity of the valve mechanism and the chamber-.12 of motor are the only factors provided for.

the feed bar is our improved throttlevalve reducing the pressure in the. feed-bar casing,-

mechanism, which maybe designated in its .it is found in practice that thedei-red reity [1'6 ofthisvalve piece protrudes beyond the valve block and is equipped with an op t the crating head 17 which is secnred'theret-o by M sult is attained to the maximum degree by the employment of this chamber. There is still another very important feature of advantage resulting-fromthis chamber since the machine is'se balanced that the-vibract' that in our construction the mofluid is first allowed to pass to the and since a partial 0 using of thethrottle 'tion is igreatly reduced. Attention is called once and in comparatively small quantities,

lowed to pass into the engine in comparaa set bolt 18.' In the basefof this valve is a chamber 28 in the head block. It passes I thence in opposite directions lothe feed bar t the cylinder, thus opening a continuous pascasing and engine respectively. This gives! a balanced result/because ot' the fact that From the foregoing description the use the motive fluid is passing simultaneously in oppcsite directions to the two instrumentalities, the force of theflmd in opposite directions having a neutralizing effect and greatly. reducing the vibration as compared with the result in those constructions in which the motive fluid passes first to the feed bar casing and immediately acts or produces a tendency to move the machine in the rearward direction so far as the instability of its support will permit, and then as the-fluid passes in the opposite direction,

there is a resultant vibration produced which is entirely absent in our construction. The valve piece 14 is provided with 3 U-shaped passage 31 formed in its upper portion and adapted when the valve piece is properly adjusted to register with the passage 24, whereby the motive fluid from the chamber 12is allowed to escape to the atmosphere, the passage 31 bein continued through the operating head ofthe-valve piece as shown at- 32. The valve piece 18 also provided-with a passage 33 extending transversely therethrough and adapted when the valve is properly adjusted to register with the.-

passages

22 and 26 of the valve bloclt,. to allow the motive fluid to pass from the chamber 28 to the feed bar chamber 12 simultaneously with its passage from the supply chamber 28 to the cylinder chamber for operating the hammer.- The valve piece is further provided with a port 34 which when the valve is in the positi n .to cause its passage 33 to register with

t e passages

24 and 26, iopens communication between the annular recess 19 of the valve piece and the passage; 2 of the valve block, thus allowing the motive fluid topass freely from the supply con'dtiit 20 to the supply chamber 28. The valve block is also provided-with passages 35 and '36, the latter communicating at ,its forward extremity withan exhaustpassage 37 formed in the.

wall of theeylinderlieand the casing 30 of the valve mechanism; 7,: the for'warrtextremity of the assage 37 communicating by a port 38 with the cylinder chamber 39 just in {the rear of the rear-extremity of the hammer 6 when the latter is at or ap' proximately at its forward limit of move ment. .The rear-extremity of the passage- 36 communicates as shown at 40 with the valve chamber 25.

l the. chamber 25 as shown at 41, and at its ,shown at 42. When the valve piece 14 is rear extremity with the atmosphere as properly adjusted a cavity 43 formed there- The passage 35 com-- "mnnicates at its forward extremity with sage from the forward portion'of the cyl inder to the atmosphere.

and operation ot'ourimproved throttle valve this case the mot ivc tluid'is cut ofi' from the first be turned to the position shown in Figs.

'2 and 5, in which event a short passage 4% formed in the valve piece places the passage 23 of the valve block in communication with the annular recess 19 of the valve, thus allowing the motive fluid to pass to the feed bar chamber 12. whereby the drill bit is pressed against the breast of the rock preparatory to the commencement of the drilling work. Now in order to start the hammer the throttle valve is given a further partial rotation as indicated in Fig. 6. whereby the passages 23 and-4t are cut off from theinotivetluid, the valve piece, however, being turned sufficiently to allow the motive-fluid to pass tothe chamber 28 through the wort 34 of the valve, through the passage 2t ot' the valve piece, and thence from the chamber 28 through the passage 26 of the valve block, the passage 33 of 'the valve piece, and the passage 22 of the valve block to the feed bar chamber 12. As illustrated in Fig. 6, however, the passage 33 of the valve piece is only partially placed in register with the

passages

22 and 26. In this event the hammer will he slowly reciprocated and the-auxiliary exhaust is not employed, since the passages.

35 and 36 are not placed in communication, the cav1ty'43 not being 111 position to con- ,nect the

passages

35 and 36. Now it it is desired to run the drill at maximum speed, the valve piece Will be given a further partial rotation in the same direction, whereby the passage 33 of the valve piece is placed in full register with he

passages

22 and 26 of the valve block, the port 34 of the valve piece and the passage 27 of the valveblock being also simultaneously placed in full register to allow the mam'mum quantity ofmotive fluid to pass from the supply conduit 20 to the supply chamber-.28, and thence to the cylinder chamber 29 and the feed bar chamber 12. In this event the movement of the valve piece also places the cavity 43 in position to connect the passage 36 with the passage 35,'thus openin a. continuous exhaust passage from the orwaivl portion of the cylinder chamber to the atmosphere by way of the port 38,.the-pw chamber to the said casing.

said chamber being arranged to constantly is in, operation, the valve-and head block with a feed bar casingand a drilling engine,-

means for delivering and throttling the mobar casing and -of a head block interposed between the feed cation with the engine and feed bar casing,

sa es 37 of the valve cylinder, the passage valve piece and the passage 35 of the valve block." Under these clrcumstances the hammer (3 will be reciprocated'at its maximum? speed and the auxiliary exhaust will be utilized as heretofore explained.

Having thus described our invention, whatwe claim is:

1. In a pneumatic tool equipped with a 5 feed bar casing .a piston movable therein and l a motor, the combination of a head block casing for constantly supplying motive fluid 1n common to both the said casing and said motor when the latter is in operation, and

tive fluid on its way from the sourceof supply to said chamber, the latter being locah d on the'opposite side of the throttling means from the feed bar casing, the head block having a passage leading from the said '2. In a hammer drill equipped witha feed bar casing and an engine, the combination of a heat block interposed between the feed said engine and having a relatively large chamber in comnmnication with the engine and feed bar casing, the

supply motive fluid in common to both the said casing and said engine when thelatter is in operation. the heiid block having a passage'leading from said chamber to the teed bar casing, and means located between the said chamber and said casing for delivering and throttling the motive fluid on its way to the said chamber.- I

3. 'In a hammer drillequipped with a feed; bar casing and an engine, the combination bar casing and said-engine and having a relatively large. chamber in communication with the engine and the feed bar casing, the said chamber being arranged to constantly. supply motive fluid in common to both'the Saideaing and said engine when the latter having passages leading from the said chamher to thesaid casing, and athrottle valveloeated int-he head block for controlling the motive fluid on its way to the said chamber, the latter being located between the said valve and the engine. i

4. In a tool of the class described equipped theeombination of a-block interposed between s'aid-easing and said engine and hay; ing a relatively large chamber in communisaid chamber arranged to constantly supply motive fluid incommon to both the feed bar casifigland said engine when the latter purpose set forth.

is in operation, a valve journaled in said block for throttling the motive fluid on its 36 of the valve'bloek, the cavity 43 of the way to said chamber. the latter being 10- A thesaid .valve and the said throttle valve mourited n said block, the? latter being provided with passages located on opposite sides of th'evalve, and a'rela-' tively large chamber in communication with the engine and 'feed bar casing,'the"said chamber being arranged to constantly suppl v motive fluid 1n commonftoboth the feed bar casing and-engine when the latter is in o eration, the said chamber being located one of said passagesin the head block extend ng toward the engine and communirating with the said motlve fluid supply between the throttle valveand the'engine,"

chan bcr while'the other passage is located valve and head block having a passage for the siupply of motive fluid to the said cham-- her, the.valve having a passage adapted to on o posite'sides of the valve, when the eugme is, in operationz' reginter with the passages in the headblock (3. In a tool of the class described equipped with a feed bar casing and a drillcylinder, the combination of a head block sages for simultaneously regulating the sup-.

plv of motive fluid to the feed bar casing interposed between the said. casing and ovhiu ler, and a on the opposite side of the valve and. in coml i nnnneation with the feed bar casing, the

and the drill cylinder, ahd fora'cgulating the cxhaustfrom the feed bar casing and drill c vlinder.- 4 p 7. In a toolof the class described equip ed with a feed bar casing and. drill'eylin er, the combination of a h'cad block interposed between the said casing and said cylinder, orts and passages located in the valve and head block for simultaneously regulating the supply of motive -fini'd to the drill cylinder and feed ,bar casing as the valve is my tated,-the head block also'havingexhaust passages which: are arranged to be placed in communicationwith each other when the valve is adjusted, the latter having a cavity for the purposelwhen it is placed in position,

tov deliver themaxiinum supply of motive fluid to the feed bar cas'ing and drill cylinder, the said exhaust passages being in co'mmunication with the drill cylinder for the S. in a tool of the class described equipped with a feed bar casing and a drill cylinder.

the combination of a head block interposed between the -feed bar casing and drill cylinder, a throttlevalve rotatably mounted in said bloc k, and exhaust passages 'formed' in the said block, the said valve having a cavity adapted when the valve is properly adjusted to place the said passages in communication with each other, the wall of the drill cylinder having an exhaust passage leading from the forward portion of the cylinder and communicating with one of the exhaust passages in the head block.

9. In a tool of the class described equipped with a feed bar casing and a drilling engine, the combination of a head block interposed between the said casing and said engine, a valve mounted to rotate in said block, the valve and head block having passages for successively regulating the supply of motive fluid troni the source of supply directly to said feed bar casing forsetting the drill againstthe rdck and placing the feed bar casing in communication with the atmosphere for exhaust purposes, the head block having a relatively large chamber located adjacent the engine, the alve and head block having passages for conducting the motive fluid from the said chamber to the feed bar casing. for constantly supplying motive fluid to-the teed bar casing when the engine is in operation, means for throttling the motive fluid on its way to the said chamber, the'latter being external to the throt-' tling means.

10. In a tool of the character described equipped with a feed bar casing and a drilling engine, the. combination of a head block interposed between the said casing and said enginmfand the head: block having a relatively 'ela'rge chamber located adjacent the enginefand in commimication with the engine and feed bar casing, for supplying motive fluid in common to the said chamber and said engine, and a throttle valve rotatably mounted in said block, the valve and head block being equipped with passages for simultaneously admitting motive fluid to said chamber in the head block and from said chamber to the feed bar casing, and for successively admitting motive fluid directly to the feed bar casing to set the drill against the rock and for placing said casing in communication with the atmosphere for exhaust purposes.

11. In a tool of the class described equipped with a feed bar casing and drill cylinder, the combination of a head block interposed between the said casing and cylinder and a throttle valve rotatably mounted in said block which is supplied with a relatively large'chan'iber adjacent the drill cylinder, the valve and head block having passages for conducting motive fluid to the feed bar casing to set the drill against the rock, and for simultaneously regulating the supply of motive fluid from said chamber to the feed bar casing. the latter being also in communication with the said chamber, the valve and head block also having passages for regulating the exhaust from the feed bar casing and drill cylinder substantially as described.

12. In a tool of the class described equipped with a feed bar casing and drill cylinder, the combination of a head block interposed between the said casing and said cylinder, ports and passages located in the valve and head block for delivering motive fluid tothe t'eed bar casing to set the drill against the rock, and for simultaneously regulating the supply of motive fluid to the drill cylinder and teed. bar casing as the alve is rotated, the head block also having exhaust passages which are arranged to be placed in communication with each other when the valve is adjusted to deliver the maximum supply of motive fluid to the feed bar casing and drill cylinder, the valve having a cavity for the purpose, the said exhaust passages being in communication with the drill cylinder for the purpose set forth.

In testimony whereof we atlix our signatures in presence of two witnesses.

VINCENT J. (YBRIEN.

tOMlfit) (I. IUVKERMAN. lVitnesses:

A. J. BRlEN,

F. E. BOWEN.