US1018983A - Pneumatic tool. - Google Patents

Description

Patented Feb, 27, 1912. B

[N VEN TOR PVITNESSES Home .29 vide means for cushioning the valve in such a manner that the some. will start and stop I, UNITED. ermine-PATENT OFFICE.

JOHN J. PADBURY,

F MCKLAND,'MAINE, ASSIGNOR TO LIVINGSTON MANUFAC- TURING COMPANY, OF ROCKLAND, MAINE ,PNE MATIC TOOL.

Specification 01. Letters Patent. I Patented Feb. 27, 1912 "12; at! it concern Beit'known that 1, JOHN J. PAnnonY, a

citizen of the United States, residing at Rocklend, county of Knox, State of Maine,

liave. -invent ed certain new and useful l npro've'inrien'ts in Pnenmatlc Tools, of wh ch .i the 'iiollo'wing is a specificat on, reference hei'ng htid therein to the accompiinying drawing.

This invention relates to ce'rtiiin new and. 'useful improvements 1n pneumatic harry niers, and more particularly to pneu'matlc chipping tools, the object-being to provide steel in which the initial movement of the pistqnin its upend down stroke is gradual, caused by the reduced pressurearea of the respective ends of the piston which prevents i the'jerking and vihratir'igof the tool to a great extent.

Another object of the invention is to pro-- 4 gradually' whereby the pounding of the diflieulties now existing with pneumatic toolsw' valveiis prevented in order to inereasethe lifefof the some and thereby overcome the A further ohjtiet of the invention is to provide a. reversible piston in order to allow the sameto be reversedwhen the imphct portion becoines worn, thereby; increasing the life of the'piston two-fold.

A still' further object of the invention,

to provide a pneumatic tool which is ex- I ceedingly simple and cheepin constructionand one iii-which the parts are so mounted thiit they may he easily and quickly taken f ap rt, and one which very; strong and position; Fig. 2'is a; 51

50. gagement with the shank (if a c pping tool;

durable, the parts being so"- 'conn ected' that all danger of the same work ng loose, while in (ring-ration, is prevented.

Othei imd further oh ects'hnd advantiiges of the invention will he hereinafter set forth und the novel features thereof defined by the 'tippei ded claim.

In the v'drawing-Figure .l. is a longitudinal sectional elevation threugh myjniprqved pneumatic tool shownigrlgi e piston in raised and :Fig.'3' is an elevationqmrtly in section of the valve detached.

Like numerals of reference refer to like plirts in the several figures of the drawing.

formed'in theviilv'ejhl0ek,-the?uppe1r end of a r 'view showing Application filed June 26, 1911. otta). No. 835,378.

tion 7 of a handle 8 which is provided with a chamber, in which is',. mounted a valve block 10 ivhiehhe'ers against a cylindercap 11 as clearly shown and locked in position by pins .12, only one of which is shown.

The handleisprovi'ded with en inlet passage 13 to which is connected a Supply pipe 'l-l for supplying the-motive fluid, said pas- 5 sage 13 communicating with a chamber 15 formed in the valve block in which is mounted a valve 16 lowing ends'lf sndllS of difi'er rntisizes forriiingdifierent: pressure areas, and a central annular passe e'fo i purpose later-described. .The'end-I oft e vel've is provided with. a projection 19Jwhich c'o-ects with a chamber 20 formed in. the cover 11' in order to'coshionthe valve on its'dovm stroke which also -redijces- 'the pressure ares 5 on the initial movementof the valve inorder 'to reuse the sagne tolmov'e 'slflwly uptil the projection leaves he chamber? v Extending loniti inally throughthe vided with Sorts EQ-uhd. 23, the n perend of the passage communicating iii/"it :a pas Stage 24 lending into the vnlvejchamher 15 and through which motive flll'id fifi adiip ted to pass and-act upon-the enlarged ress'ur'e v 5 nreaof the yalve in. order torelsejt e some.

In the opposite wall of theffvlinder', a pessage 25 1S formed which is providedfwith s 'portQt} 'communicetingwith. th cylinder hnd at-itslupir end reEisterswitliepessage 217 extending throng the cylinder cover.- which, in turn, registers wlthxe 'pessage 28 said-passage registering with the inlet pa sage 13 formed"'n't hehandle in 'orde ;m allow motive fluid tobe supplied tug-the cylinder.

Mounted some the cylinderjis I 29 provided with reduced ends'30, one of.

which forms an impact portion' adopted to shown in Fig l. A formed in the valve block which communiimpact the end of the shank 4 of the tool 5 said curl fitting snugly within the reduced Jgvrtien of the cvlincier as clearly shown in ig. .2, and it will be seen thatby this construction, the piston can be reversed inorder to bring the opposite end into position to impect the tool. The upper reduced portion of-the piston enters a chamber 31 formed in the cylinder cover in order to cushion the up stroke of the piston and communicating with the chemher 31 are divergingpassages 32 which register with passages 33 leading into the valve chamber in the valve block ami through which live steam or air is adopted to be admitted when in the position shownin Fig. 2 and through which the steam or air is-eilapted to be exheustedus Au exhaust passage 34 is notes with achernber 35 surrounciin the valve hlock and is provided with an ex aust port 36. The cj'iinrle-r is provided with an exhaustport 37st its lower enci through. which the motivefiuid is exhausted on the ilown stroke of the piston. An annular groove formed centrally in; the piston 29 orming e geese-age which registers with theis supplieti \nrough the pipe 14, which iney' he provided with e throttle if desired, into the yassugs 13 and passes into the cylinderthroiigh the port 26 around the groove:

of the piston through the port 23 into the passage 2L A. portion of the fluid pressure passes out of the port 22 lii Ader the lower end of the piston nucl it will be seen that the pressure arse of the piston is reduced by the project-toil being within the'r'educed portion of the cylinder which causes it slow initial movement of the piston and at the same time air passes into the valve chamber 1.5 Zn the valve block against the large pres sure area of the valve which, likewise, has

piston enters the chamber 31 and forms i cushioning action in order; to reduce the jar as much as possible. are then closedh'y the piston and the motive fluicl acts upon the reduced urea of the valve and forces the same into the position shown in Fig. 2 and the inotive fluid passes through the passages from the valve chem her into the upper end of the cylinder into the chamber 31 so as to produce it. slow initiul movement which is caused by the reduced area of thepiston until it has left the chamber which allows the fluid power to have full pressure upon the piston in order to cause the "same to im met the shank of The dead n11" within the lower the tool. end of the cylinder is forced out through the exhaust 37 and the operation'is continued which causes a of the piston?" I Having described my invention end set forth its merits what I claim RRCi'TlGSli'B to secure by Letters Patent is,

A pneumatic tool having a cover at one end provided with chenibersin its inner and outei faces", a piston mounted in said The ports 23 and 26 continuous reciprocation cylinder having a reduced portion come-ting" with one of said chambers, and a valve hav ing it reduced portion (Jo-acting i'vit'h' the chamber upon the opposite faceishisuirl cover. 1 l v In testimony whereof I nfiiv my sigimture in presence of two witnesses;

JOHN'J'. PADBURY. Witnesses r GHAS. .SMALLEY; E. H. Lowni

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