US1700419A - Lubrication of tools - Google Patents

Description

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Patented 29, 1929.

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'EOI1 CQMPANY, 019" NEW YORK, N. 712.,

GAR, ASSIGNOB TO CHICAGO PNEUMATIC A PORPORATION OF JERSEY.

LUBRICATION OF TOOLS.

Application filed January 27. 1925. Serial No. 5,008.

This invention relates to tools having a reciprocating element, such as percussive tools, particularly of the fluid pressure type, and more specifically to the manner of and means for lubricating the working partsthereof. It represents an improvement upon and further development of a similar invention disclosed in my copending application Serial No. 674,443 filed Nov. 12, 1923,

Among the objects of the invention are to provide efiective and adequate lubrication of the parts of tools of the described type but to prevent flooding and waste of lubricant when the tools are notin operation, to facilitate the removal of any foreign matter which might clog the lubricating system, and 1n character in t 'ing the throttle valve in adifi'erent position.

' cylinder ciprocat es under the impulse of motlve fluid spectively.

rove prior arrangement of this e interest of more eflicient and satisfactory service.

lnorder to illustrate the invention and the manner of its operation concrete embodiments thereof are shown in the accompanying dr wings in which:

ig. 1 is a longitudinal vertical sectional view of a hammer drill embodying the invention; y

Fig. 2 is a detail sectionalview of a portion of the drill shown in Fig. 1 but showgeneral to im Fi 3 is a transverse sectional view sub-, stantially on theline 33 of Fig. 1; and

Fig lis apartial longitudinal sectional view similar to Fig. 1 showing a modification.

The invention is disclosed for thepurposeof illustration as embodied in a percussive rock drill of the fluid pressure type having a cylinder 5 provided with a front head 6 and back head 7 held in assembled relation in the usual manner as (Fig. '3). ithin the piston chamber '9 of the impact member'or piston 10re under pressurewhich enters the tool at 11 (Fig. 3) under the control of a manually operated throttle valve 12" actuated by handle 13, by which valve the motivefluid is admitted through dpening'14 to a passage 15 whichv leads to an automatic distributing. valve (not shown) arranged to admit the motive fluid to the pistonchainber alternately above and below piston 10 through ports 16 and 17 re- An extension 10 of piston -10, guided by the block or guide slepve 18, reciprocates'in the front head 6 and imparts blows to a working tool or di'ill bit 19 176- above is limited at .at' least one able means which may take the orm of a plug 110 movably supported in a chuck 20 rotatively mounted in the front head. Exterision 10 has vertical ribs 10 cooperating with grooves 111 a rotative sleeve 21 keyed to chuck 20 where? by rotation of the piston is imparted to the drill bit. In the form shown the piston is rotated by the usual rifle bar mechanism com prising rifle bar 22 rotatively mounted in hearings in the back head 7 and cylinder ring 23 and cooperating with a rifle nut 24 secured 05 in the cylindrical bore 25 of the piston, the rifle bar having thereon a pawl carrier 26 which fits in a chamber in the back head and has pawls arranged for cooperation'with a ratchet ring 27 in the head.

By reason of the high-speed at which a percussive tool of this type operates and the friction developed by the cooperating parts or the rotating mechanism, frequent andade- 'l'il quate lubrication is a necessity in preventing ra id wear, but it is highly desirable that the lu ricant should not flood the piston chamber since such a condition clogs and impairs the efiicient operation of the drill. The lubricating system, which is now abont to be described is designed to provide a 'dequate lubrication of all workmg parts but to prevent access of lubricant to the working parts when the-drill is. not in comprising the present invention,

operation. The chamber or reservoir for oil or other fluid lubricant may be in any suitable or desired position in the tool; it is prererable, however, but not essential, that the outlet be disposed above the reservoir so that the lubricant must be forced against gravity; so

in the present instance the. oil reservoir 28 1s pos tioned 1n the guide sleeve 18 orhetween 1t and the cylinder wall, the same being by side or through rods 8 arranged to be filled with oil 29 through anopening closed by plug 30. A passage adapt 96 ed to be made continuons when the drill is operation leads from reservoir 28, this pas-f sage comprismg passage 31 in cylinder 5, the; end of which registers with a passage 32 in the baekhead 7 which leads upwardly andlOt another passage 34 in back head 7 which in 106 .turn registers with a bore or passage 35 in the-ratchet ring 27. The flow of fluid'through the passage comprising the parts enumerated oint by suita portion of the lubricant passage. As indicated this plug'is readily removable for cleaning without disassembling any of the parts of the drill.

v The groove 33 in the throttle valve 12 places the lubricant passage under control of the throttle valve and it is to be noted that this groove is so positioned relative to the inlet opening 14 that the passage from the lubricant reservoir 28 is made continuous or established only when the drill is in operation (Fig. 1) and is brokenor interrupted when the drill is not inoperation (Fig. 2).

With the parts in the position shown in Fig. 1 there is a contin'uouspassage from the lubricant reservoir 28 to the pawl and ratchet chamber of back head 7 Communication is intermittently established between this chamber and the piston chamber by a groove 37 in the cylinder ring 23 (Figs. 1 and 3) which is alternately covered and uncovered by the radial extensions of the pawl carrier 26. In

normaloperation the rifle bar 22 rotates with the piston 10 during one stroke in a counter clockwise direction (Fig. 3) at high speed and the groove 37 makes the ratchet chamber and consequently the lubricant passage eX- tending therefrom to the lubricant chamber subject to the fluctuations of pressure in the piston chamber. In consequence during the down stroke of the piston pressure fluid enters the lubricant passage and some of it reaches the lubricant chamber and builds up pressure in the same so that when the piston reaches the outer limit of its working stroke (Fig. 1) and uncovers the main exhaust port 38 the sudden drop in pressure in the piston chamber causes the lubricant to fill the passage and-spurt into the ratchet chamber to lubricate the parts therein whence it finds its way through the groove 37 around the reduced neck of the rifle bar, and thence to the sides of the piston chamber and along the rifle bar and is carried by the motive fluid to the rotating parts of the front head.

A modification of the invention is shown in Fig. 4 wherein a throttle valve 12 of slightly different form is used. This throttle valve has a restricted port 39 communicating with the interiorof the throttle valve andwith a groove 33! corresponding to groove 33 in valve 12 of Fig. 1. By this arrangement the throttle valve 12 can be adjusted so that the lubricant chamber communicates only with the motive fluid supply within the valve as indicated by the dotted line position of valve 12 in Fig. 4. With the valve so disposed the lubricant in the reservoir is gradually displaced by the motive fluid and' the lubricant so displaced enters the'throttle valve and is carried by the motive fluid into the drill. By shiftingthe valve 12 to the full line position of Fig. 4 the lubricant chamber is placed in communication both with the piston chamber and with the motive fluid inlet so that a portion of the lubricant spurting from the lubricant passage follows the course outlined in the discussion of Figs. 13 into the piston chamber and a portion enters the valve 12 and is carried by the motive fluid to the automatic distributing valve (not shown) and thence into the drill.

While the forms of the invention herein disclosed are at present the preferred embod iments, it is to be understood that they are illustrative only and that the invention ineludes all modifications and adaptations coming within the scope of the appended claims.-

I claim:

1. In a fluid pressure tool having a piston chamber, a piston reciprocable therein, motive fluid conduits leading to. said chamber,

means for manually controlling the admission of motive fluid to said conduits, alubricant chamber, a passage under control of said passage providing a continuously open conduit therethrough-of restricted size, said last named means being accessible for cleaning without disassembling'the tool. 3 3 3. In a'percussive tool having ,a piston chamber and an impact piston reciprocable therein, a lubricant chamber, said last named chamber being closed save for a passage terminating above the same and adjacent parts to be lubricated, means intermittently establishing communication between said passage and the piston chamber, and a plug mounted 1n a bore intersecting said passagefor limiting the movement of fluid through said passage, said plug being removable without disassembling the tool. a

4. In a percussive tool having apiston chamber, a piston reciprocable therein, means for admitting motive fluid to said tool, a'

lubricant chamber, a passage under control of said means for establishing communication between said chambers, a plug intersecting said passage and arranged to permit continuous flow of fluid therethrough but in limited amount, said plug being readily removable without disassembling the tool.

5. In afluid pressure operated tool, a piston chamber, a piston reciprocable therein, a valve for controlling the pressure fluid, a 1ubricant chamber, a passage extending from secting one of said passages and arran ed to W said chamber, and means under control of limit the flow of fluid therethrougmsai plug said valve for establishing connection of being readily removable without disassemsaid passage separately with both said piston bling the tool.

l c chamber and the pressure fluid inlet when the 10. In a fluid pressure operated tool, a lu-' valve is in tool operating position. bricant chamber, a passage extending thereto, as 6. In a fluid pressure operated tool having means for selectivelyestablishing connection a piston chamber, a piston reciprocable therebetween said passage and the pressure "fluid in, conduits leading to said chamber, means inlet, and means inserted in said passage proincluding a throttle valve for controlling the viding a continuously open connection of re admission of motive fluid to said conduits to stricted size therethrough, said last named i operate said piston, a lubricant chamber, pas means being removable tor cleaning without sages extending from said chambers respecdisassembling the tool. tively, and means operating in response to the 11. In a pneumatic hammer drill having a operation of said throttle valve "for making cylinder, a cylinder ring closing one end i or interrupting the connection between said thereof, a front head for the other and arotatpassages and between said passages and the able chuck for a working toolin said front motive fluid inlet. head, a hammer piston reciprocable within '2'. in a fluid pressure operated tool havsaid cylinder and keyed to said chuck, rifle fi l ing a piston chamber, a piston reciprocable bar rotation mechanism mounted in said therein, conduits leading to said chamber, backhead for coaction with said piston, a means including a throttle valve for controlthrottle valve for controlling the pressure ling the admission of motive fluid to said confluid, and means for lubricating the moving duits to operate said piston, a lubricant chainparts in synchronism with the reciprocation 25 her, passages extending from said chamber. of said piston comprising a lubricant reserrespectively and terminating adjacent said voir adjacent said fronthead, apassage from valve, said valve having a groove for estabsaid reservoir under control of said valve v lishing connection between said passages in leading to saidbackhead and terminating adone position of said valve and having a bore jacent said rotation mechanism, and means 30 intersecting said groove for connecting said undercontrol of sald mechanism for interpassa es with the motive fluidinlet. mittently establishing connection between 90 8. n a'fluid pressure operated tool having said passage and the piston chamber. a piston chamber, a piston reciprocable there- 12. In a pneumatic hammer drill having a in, conduits leading to said chamber, means cylinder, a cylinder ring closing one end 35 inclu-d a throttle valve for controlling the thereof, a front'head for the other end, a roadmission of motive fluid to said conduits tatable chuck for a working tool in said front to operate said piston, a lubricant chamber, head, a hammer piston reciprocable within. passages extending from said chambers resaid cylinder and keyed to said chuck, rifle spectively and terminating adjacent said bar rotation mechanism mounted insaid back- 49 valve, said valve having a groove for estabhead for coaction with said piston, a throttle lishing connection between said passages in valve for controlling the pressure fluid, and one position of said valve and having a bore means for lubricating the moving parts in intersecting said groove for connecting said synchronism with the reciprocation of said passages with the motive fluid inlet, and a piston comprising a lubricant reservoir ad- 45 plug intersecting one of said passages and jacent said front head, a passage from said arranged to limit the flow of fluid therereservoir under control of said valve leading through. to said backhead and terminating adjacent 9. in a fluid pressure operated tool havsaid rotation mechanism, means under coning a piston chamber, a piston reciprocable trol of said mechanism for intermittently 50 therein, a throttle valve for controlling the establishing connection between said passage admission of motive-fluid to said tool to op.- and the piston chamber, and a plug mounted 1 0 I crate said piston, a lubricant chamber, pasin a bore intersecting said passagp for limitsages extending from said chambers respecing the flow of fluid therethroug said plug tively and terminating adjacent said valve, being readily removable without disassem- 55 said valve having a groove for establishing bling said tool.

' connection between said passages in one posi- Signed by me at Detroit Mich, this 16th tion of said valve and having a. bore interscot- 'day oi January, 1925. ing. said groove for connectin said passage with the motive fluid inlet, an a'plug interv ERNEST PENBERTHY.

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