US2966814A

US2966814A - Drilling machine

Info

Publication number: US2966814A
Authority: US
Inventors: Frank H Mueller; John J Smith
Original assignee: Mueller Co
Current assignee: Mueller Co
Priority date: 1956-11-15
Filing date: 1956-11-15
Publication date: 1961-01-03
Anticipated expiration: 1978-01-03

Description

Jan. 3, 1961 F. H. MUELLl-:R ETAL 2,966,814

DRILLING MACHINE Filed Nov. l5, 1956 6 Sheets-Sheet 1 INVENTORS FRANK H. MUELLER JOHN J. SMITH M2M, .22g/2M...

ATTORNEYS Jan. 3, 1961 F. H. MUELLER ErA-L 2,966,814

' DRILLING MACHINE Filed'Nov. 15, 195s 6 sheets-sheet 2 p, www.

22 roo INVENTOR 2o FRANK H. MUELLER JOHN J. SMITH Jan. 3, 1961 F. H. MUELLER EHU.l 2,966,814

DRILLING MACHINE Filed Nov. 15, 1956 FGJ. FIG/2.

6 Sheets-Sheet 3 INVENTORS F K H. MUEL LER J J. S M IT H ATTORNEYS Jan. 3, 1961 F. H. MUELLER ErAL 2,965,814

DRILLING MACHINE Filed Nov. 15, 1956 6 Sheets-Sheet 4 FIG FRANK H. MUELLER JOHN. J. SMITH ATTORNEYS Jan. 3, 1961 F. H. MUELLER ErAL 2,966,814

DRILLING MACHINE Filed Nov. l5, 1956 6 Sheets-Sheet 5 25e ,278 258 23e l u .nl 2:4/ 252 244, 280 276 25o V2 2|e 274 234 |42 264 27o FIG I3 246* 262 /88 les l s2 'le eo INVENTORS FRANK H. MUELLER JOHN `LSYMITH Jan. 3, v1961 Filed Nov. 15, 1956 F. H. MUELLER ETAL DRILLING MACHINE 6 Sheets-Sheet 6 INVENTOR S FRANK H. MUELLER JOHN J. SMI

ATTORNEYS DRILLING MACHINE Frank H. Mueller and John J. uSmith, Decatur, Ill., as-

;Sigllors toMueller Co., Decatur, Ill., a corporation of -Illinois Filed Nov. 15,'1956, Ser. N0.'622,47 0

13 Claims. (Cl. 77.-40)

v-This invention relates to enclosed drilling and tapping machines of the type employed to cut an opening 1n,a wall of a fluid chamber, thread thecut opening,

and screw into the tapped opening a fitting, such as a valve body or a service T for connecting a branch line `tothe fluid chamber. .Such operations are customary,

for example, in attaching lateral or service connections to a fluid conduit, such as a water` or a gas main, while the latter is in service.

In particular, this invention pertains to improvements in'machines of the type disclosed in U.S. Patents Nos.

2,291,979 and 2,745,669.

' Themachinesjdisclosed in the aforementionedpatents, while outstandingly `successful :for their intended purposes, are susceptible of improvements to Afacilitate' their operation.

Thus, it has been 'found'desirableto improve the connection Vbetween .the boring bar of the machineand the tool carried thereby. The objectswof such-improvement are to provide a construction wherein nospecial vtools are required to secure the toolto the end of the -boring bar, and wherein such construction facilitatesthe been found that occasionallythe yoke tends to--slip off such shoulder on the boring bar, with the consequent annoyance and delay ,of .having to A.back Aup the feed Acollar and re-engage the yoke. ilHence, it is vanother object of this inventionto correct-this deficiency.

'In present-day machines y,of Ythe. type `under consideration, the boring bar-normally` is driven -manually by a ,ratchet wrench, but 4inthe improvedtconstruction under ,consideration here, it is desirableto-:provide an improved ratchet wrench which not only may be utilized to drive the boring bar by.hand,-but also maybe 4used tofacilitate the attachment and detachment of tools to VJand from .the boring bar. Hence, itis another object of this invention to provide suchanimproved gwrench.

Additionally, as previously stated, theboringbars of the machines of the type under consideration substantially always have been driven by hand, by means of a ratchet wrench. The manual drive of a boring bar, however, becomes quite fatiguing and time-consuming --when drilling operations are `being performed, although the tapping operation, after an opening Ahas -been cut in Lthe main, may vbe accomplished quite-readily by hand -withounundue fatigue or consumption -ofetime Accord'- ;ir1 gly,fit,'isastill another object of this invention-'to vproice kof the type under consideration, which'attachment may be used to provide both a power drive and ari-automatic `feed for the boring bar during =drilling. operations.

ping machine embodying this invention. The machine is shownattached to a main andwith theparts ingtheir position at the termina-tionof attappingeperation.

Figure 2tis an enlarged,;fragmentaryperspectivezview of the machineshown inFigure 1. L

Figure 3 is an enlarged, fragmentary-.viewpfthetoolcarryingend ofthe boring bar ofthe machineeshowniin Figure l.

Figure 4V is a-sectional view-taken 4vs1 1bstantially pon line 4-4 of Figure 3.

Figure 5v is an enlarged, sectional view with parts broken `away to illustrate details, taken substantiallyfon line 5-5 of Figure 1.

Figure 6 `is an enlarged, 4fragmentary view, VApartly-,irl vertical sect-ion, of` the machine ,shownin Figure `1 and illustrating-the construction `ofthe-ratchet -wrench and its attachment to themachine.

Figure 7 is a plan view.takensubstantially'onaline 7-7- 7 of Figure 6.

Figure 8 is ak sectionalviewlakensubstantially on line -Sf-:Sof `Figure 6.

Figure ,9 is a fragmentary plan view `of thegchaingyoke shown in Figuresl ,and 2.

Figure 10 is anenlarged,fragmentary,.sectional-view taken lsubst-antially on line 10, 10-of-Fi gure -9.

Figure 11 is an enlarged, fragmentaryfview, partlyfin vertical section, illustrating the use ofa stop-,carrier, em

4bodyingthis invention, for attaching .afcorporatlonqstop to a main.

Figure 12 is a sectional .Viewftaken .substantially `on line 12--12 of Figure v11 land additionally illustrating, in fragmentary view, a s pecialftype wrench engaged with thestopk carrier for disconnecting thelatter.,frornthe-stop.

Figure 13 is a central, vertical, Y,sectional -view-taken substantially -on line 13-13ofFigure 1450i -a combined Lpower drive and automaticffeed .attachmentiforfthe :drilling machine shown in Figure lt-andshowingssuchfattach- 1vment connected tothe machine.

Figure 14 isavtopplanview-of the attachment shown in Figure 13.

`Figure 15 isabottom viewfof the attachmentzshown in Figure 13.

1Referringnow-to -the drawings, there isshownfinfFigures 1 and 2 a curved wall chamber, suchlasa gas zor Water main 20, -having mounted thereonthe usual, saddle `22. with a gasket I.24 interposed therebetween. The saddle 22 has an ,opening therethrough vv that is rcounterbore'd at its outer r end to 1- receive ythe lower-open vend -of a :op valve housing26. A gasket 28-is interposedbetween the saddle 422and thehousing V26.

The housinglo isvhollowand bulgesoutwardlvat one side thereof to :form a 4lateral enlargement i3tl-for1the reception of -a flop valve 32 when thejlatter isiny' its lopen or inoperativeposition, asbest .shownin gFigure :1. The flop valve 32 is carried on a shaft 34;journaled in the walls of the housing26 `and provided with-yan :exterior handle 3 6 to t move .the valvetinto or. out' of-engagem`ent with a valve seat `38 inthe housingfto either close l,or open the valve. The vOpen upper end of theop valve housingl26 isinteriorly threaded .for connection u'of-one end of arcylinder 40 .which, together .with vthe ,housing constitutes thejbarrel 42 o f the machine. VPreferably, a circumferential groove'is provided in the, housing 26 ,at the inner end-o f its threadsand an O-ring44 isdisposed in such groove for ysealing engagement with a smoothwalled portion of the inner end of the cylinder 40. The upper open end of the cylinder 40 is provided with an interior reinforcing ring or band 46 and is closed by a threaded bonnet or cap 48 that is sealed to the cylinder by an O-ring 50. Preferably, the cap 48 is provided with radial handles 52 to facilitate its attachment and detachment to and from the cylinder 40. Thus, the barrel 42 and the cap 48 form an interior uid chamber 54.

Projecting upwardly from the top of the cap 48 is an exteriorly threaded cylindrical bearing extension 56 of reduced diameter. The cap 48 and its extension 56 have an axial bore 58 which forms a bearing for and through which extends an axially and rotatably movable tubular boring bar 60. Adjacent its ends the bore 58 is provided with interior circumferential grooves having O-rings 62 therein for sealing engagement with the boring bar 60. Between these O-rings 62, the bore 58 is enlarged, as at 64, to provide considerable clearance between the bore and the boring bar 60 and form an annular chamber into which lubricant can be introduced through a charging opening that is normally closed by a screw plug 66. The upper exterior end portion 68 of the boring bar 60 is square, or of other noncircular formation, best shown in Figures 6 and 8, for reception in a complementary socket or opening 70 of a ratchet wrench 72 that is used to rotate the bar by hand. For a short distance below its square end portion 68, the boring bar 60 is reduced in diameter to provide a shoulder 74 facing the end portion. A thrust collar 76 is seated against the shoulder 74 and is held in place by a set screw 78.

generally U-shaped yoke 80 has the ends of its legs or arms 82 pivotally carried by a feed collar 84 threadedly mounted on the extension 56. The base 86 of the yoke 80 has a generally U-shaped notch 88 therein, as Ibest shown in Figure 5, so that the yoke may be swung up into the position shown in Figure l, wherein the boring bar 60 is received in such notch and the yoke base may bear against the top of the thrust collar 76. In such position, a feeding movement may be imparted to the bar 60 on rotation of the feed collar 84, which rotation can be accomplished manually by radial handles 90 thereon. Preferably, a nylon washer 92 is interposed between the thrust collar 76 and the base 86 to reduce friction therebetween. Projecting from one side of the notch 88 is a spring-pressed detent 94, best shown n Figure 5, that is spaced from the bottom of the notch a distance greater than one-half the diameter of the bar 60. Hence, in the operative position of the yoke 80, the detent 94 engages the bar 60 to retain the yoke in such position. Disposed about the notch 88 and extending upwardly from the base 86, the yoke 80 is provided with a square, or other noncircularly-shaped, extension 96 (Figures 5, 6 and 13), the utility of which will be later explained.

A bypass valve 98, mounted on the op valve housing 26, is employed in the usual manner to control communication between the portions of the uid chamber 54 above and below the op valve seat 38 when the valve 32 is closed, to facilitate both tight engagement of the valve with the seat and subsequent opening of such valve. The barrel 42 is held against the saddle 22 by a chain 100 extending about the main and having its opposite ends secured to the opposite forks 102 of a chain yoke 104 that is engaged against an upwardly facing shoulder 106 on the barrel 42 formed by the upper end of the flop valve housing 26, as is best shown in Figures 1 and 2.

The lower or forward end of the boring bar 60 has an enlarged tool holder 108 secured thereto, as by welding, as best shown in Figure 3, for removably carrying a tool, such as a combined drill and tap 110 (Figure 1) or a stop carrier 112 (Figure 11). Seated against an exterior rearwardly-facing shoulder 114 on the holder 108 is a cylindrical guide collar 116 of substantial diameter and preferably provided with a bearing surface of synthetic plastic 118 having high wear and abrasion resistant characteristics, such as nylon. The plastic 118 may be in the form of a sleeve molded onto the collar 116 and locked thereto by interior circumferential ridges extending into complementary exterior grooves, as at 120, in the metal portion of the collar. This guide collar 116 has a close t within an accurately-machined cylindrical interior guiding portion 122 (Figure 1) in the flop valve housing 26, immediately above the valve seat 38, to maintain the tool properly centered at the start of a cutting operation or the carrier 112 properly centered with a tapped opening 124 (Figures 1 and 11) at the beginning of a stopinserting operation. Thus, the guide collar 116 and the interior cylindrical portion 122 prevent any side shifting of the tool holder 108, during initial cutting or inserting operations, which might be occasioned by wear of the bar bearing portions of the bore 58 in the cap 48. After the opening has been cut and during the subsequent tapping operation, the guide collar 116 may pass inwardly beyond the ilop valve seat 38, but during the tapping operation or completion of an inserting operation, it will be evident that no guiding of the bar 60 other than that provided by its bearing in the cap 48 is necessary. The exterior surface of the plastic 118 is uted longitudinally, as at 125. The guide collar 116 also is provided with a reduced extension 126 which depends from or projects forwardly of such collar about the lower portion of the tool holder 108. The guide collar 116 may be retained on the tool holder 108 by a set screw 128 which passes through the extension 126 and is threaded into the tool holder. From the aforedescribed construction, it is evident that the fluted formation of the plastic 118 provides a ready hand-hold for grasping the holder 108 to either rotate the boring bar 60 or retain it against rotation, for reasons later described.

The holder 108 is provided at its lower or forward end with a tapered socket 130 for receiving the correspondingly tapered shank 132 of either of the tools 110 and 112. Diametrically-opposed, arcuate recesses or notches 134 (Figure 3) are provided in the rim of the socket 130 for reception of the projecting ends of a transverse driving pin 136 in the tool shank 132. The pin 136 is of a length equal to or slightly less than the maximum outer diameter of the holder 108. The end of the tool shank 132 is provided with a coaxial threaded socket 138, best shown in Figures 3 and 11, for engagement with the threaded end of a draw rod 140 that extends rearwardly or upwardly completely through the boring bar 60. At its upper or rearward end, the draw rod 140 is provided with an enlarged noncircular, e.g., hexagonal, head 142, as best shown in Figure 6. In the embodiment illustrated, such head 142 is formed by a nut threaded onto the upper end of the rod 140 and rigidly secured thereto, as by a pin 144. The underside of the head 142 is adapted to bear against a thrust washer 146 seated against an interior shoulder in the upper end of the boring bar 60.

From this construction, it will be seen that the tool shank 132 may be partially inserted into the socket 130 and threadedly engaged with the draw rod 140. Rotation or tightening of the latter by its head 142 will then serve to pull the shank 132 tightly into the socket 130 and position the ends of the pin 136 in the notches 134 in the rim of the socket. Thus, the draw rod 140 can securely but detachably retain the tools 110 or 112 in the holder 108.

The inner end of the socket 130 in the holder 108 merges with a cylindrical portion 148 of somewhat greater diameter than the interior of the boring bar 60, which terminates at its inner end in a forwardly or downwardly facing shoulder 150, best shown in Figure 3. Within the cylindrical portion 148 of the holder 108, the draw rod 140 is provided with an exterior cylindrical enlargement 152, substantially complementary to and for guiding engagement wtih the interior wall surface of the cylindrical portion. When the draw rod 140 is in secure retaining engagement with a' tool, as shown in Figure 3, so that the rod head 142 bears against the washer 146, the en- 'largement 1'52on the rod 1s spaced somewhatfrom the linterior shoulder 150. The enlargement152 on the'rod 140 is provided with an `exterior circumferential groove having an O-ring 154 therein to provide a seal between the enlargement and the interior wall surface of the cylindrical portion 148 of the holder. From this construction it will be seen that the enlargement 152 prevents loss or Withdrawal of the draw rod 140 rearwardly through the boring bar 60, while the O-ring 154 prevents passage ofany fluid from the chamber 54 rearwardly through the bar.

The ratchet wrench 72 embodying this invention, and which is shown best in Figures`6, 7, .and 8, comprises a main body 156 provided with a bore or bearing aperture v158 extending therethrough and a detachable operating handle'160 extending generally radially of such bore. On one side the body 156 is provided with a counterbore 162 Vfor the reception of a ratchet wheel 164`having'extended cylindricalhub portions 166 and 168 and the central non- -circular aperture or socket'70 that is complementary to v'andfor receptionof the square 'end portion 68 of the boring bar 60. Ille hub portion166 ftswithin the body bore.158 with its outer end substantially flush with the exterior surface of the body 156. A closure or retaining plate 172 is fastenedto the other side of the body 156, as by screws 174, and hasan annular rib. or ange 176 tting within the counterbore 162 and bearing against one side of the wheel 164 to retain the latter in the body. The plate 172` is provided with a bore 178 in axial alignment with the body bore 158 but of somewhat greater diameter than the latter for journally mounting one end of a sleeve-like Wrenchvmember 180. At its one end the -member 180 is provided with an exterior circumferential flange 184 tting within an interior enlargement 186 at the inner end of the bore 178 in the plate 172. Consequently, the wrench member 180 is rotatably retained in or swivelly connected to, the wrench 72. Within its one end, the member 180 is provided with a cylindrical socket 188 for journally receiving the hub portion 168 of the ratchet wheel 164. Beyond the socket 188 the member 180 is exteriorly and interiorly reduced and provided with a smaller, noncircular socket 190 complementary to the enlarged head 142 on the draw rod 140 and for wrench engagement therewith. Secured to the reduced portion of the wrench member 180, as by a setscrew 191, is an enlarged handle` 192 to provide a ready hand-hold for manually turning the wrench member.

`Mounted in a bore 194 in the body 156 extending radial- 1y of the wheel 164 is a reversible, spring-pressed ratchet pawl 196 engageable in the usual manner with notches 198 in the ratchet Wheel, as best-shown in Figure 8.

The chain yoke 104, on kone'side thereof, is laterally enlarged as at 200, and provided therein with an upwardly facing cylindrical socket 202, of a diameter only slightly greater than the maximum transverse dimension of the square end portion 68 of the boring bar 60 and of a length substantially equal to such end portion, as best shown in Figures 9 and 10. The inner end or bottom of the socket 202 is provided with a noncircular opening or socket 204 that is complementary to the enlarged head 142 on the draw rod 140 for wrench engagement therewith. The function and purpose of the sockets will be explained later.

ln use of the machine embodying this invention, after the barrel 42 has been secured in place on the main 20 and before the cap 48 is connected to the barrel, the boring bar 60 while carrying the cap and the yoke 80 is disposed in an inverted position and the square end portion 69 of the bar placed in the socket 202 in the chain yoke 104 with the head 142 of the draw rod140 engaged -within the socket 204. The socket 202 Will support the boring bar 60 in this position while the shank 132 ofthe combined drill and tap 110 s partially inserted into the Y- tool -holder socket 130 and threadedly engaged with the 'adjacent end of the draw rod 140. Thereupon, by manu- 108, the boring bar 60 can be rotated relativeftolthehead 142 in a direction to tighten the threaded `engagement between the draw rod140and the tool shank 132.

After the too-l 110 is thus firmly secured tof` the.-.to'o1 holder 108, the boring bar 60 is inserted intrythe upper end of the barrel 42 `and the cap 48 is threadedand tightened onto the barrel. `The boring bar 60 mayv then'be pushed down manually until the tip of the tool :110 engages the main 20. Thereupon, thefeed collar:84.1s threadedly adjusted into a-position wherein the yoke may be swung into detent-retained feeding engagement over the thrust collar 76 on the boring bar. The ratchet wrench 72 is then engaged withfthe square end portion. '68 of the boring bar 60 and operated,by hand, ltorotate-lthe llatter so that the tool V/'will drill a -holein' the walllof -collar84 is rotated by hand to advance the toolrlltlfa'nd provide the necessary axial force thereon to-'effeet-a cut int the mainZit. After the main 20 hasbeen'drilledf-by the'forward drill portion of the tool 110, the following tapping portion of the tool will engage the main, and continued operation of theratchet wrench 72 .Willserve to tap the drilled opening in the -main, as is best shown` in Figure 1. In this connection, it will `be seen thatforce feed of the bar-60 duringthe tapping operation-isnot necessary because the tool 110 is self-feeding during-the tapping operation.

After the main Z0 has thusbeen drilled and tapped, the yoke 80 is swung out of engagement over the collar 76 and the ratchet pawl 196 on the wrench 7-2 Iisreversed so that reverse operation of the Wrench will serve tounthread the tool 11? from the tapped opening in--the main. Thereupon, the boring bart60 is pulled up manually -until the tool holder y1118 and the tool 110 are completelygreceived within the upperportion 'of the barrel v42 above the valve seat 33. ."fhe iiop valve 32 can then be closed and the cap-48, together with the boring bar 60, removed in conventional fashion. AThe boring-bar@ is again inverted and supported in the sockets 20i2-and 204 in the chain yoke 104, as afo-redescribed, While the -bar is manually rotated in a direction to unthread the draw rod 140 from the tool 110, -whereby the latter can be removed. At this time, the stop carrier 112,A best shown in Figure ll, is secured in the socket in the tool holder 108, in the same manner as aforcdescribed for the attachment of the drill and tap 110 therein. The stop carrier 112 has a tapered shank 132, a thre'adedcnd socket 133, and a transverse driving or locking pin-'136 identical to the corresponding portions of the drill yand tap 110. In place of the drilling and tapping portions of the tool 110, however, the carrier 112 is provided, at its forward end, with an interiorly threaded socket 206 for the reception of one of the threaded nipples208 ofa corporation stop 210. This stop-carrying socket 206 of the carrier may be substantially identical to that illustrated yand described in the above-mentioned Patent No. 2,745,669.

With the stop 210 closed, the cap 48, together with'the boring bar 60, is re-attached to the barrel 42, after Which the flop valve 32 is opened and the boring bar 60'ladvanced, either directly by hand or by the feed collar84 and yoke 80, until the free other nipple 208 of thestop is engaged with the tapped opening in the main20'. 'At

this time, the boring bar- 60 is again rotated by the ratchet wrench 72 to screw the stop 210 into the tapped opening in the main 20, as shown in Figure 1. The handle 19'2 of the ratchet wrench 72 may then be grasped by hand and rotated in a direction to unscrew the draw rod 140 to completely free the shank of the stop carrier from the socket in the tool holder. Thereupon, further unthreading rotation of the draw rod, accompanied by a slight retraction of the bar 60, will serve to completely detach the stop carrier 112 from the tool holder 16S, so that the cap 48, together with the boring bar 60, can be removed from the machine, and the chain 100 detached so that the complete machine can be removed from the main 20.

This operation will leave the stop 216, together with the carrier 112 threaded thereon, threadedly engaged in the main 20, as best shown in Figure ll. Thereupon, the stop 210 can be firmly tightened into the main 20, as by an appropriate wrench (not shown), and thereafter a special wrench 212, best shown in Figure l2, can be engaged with the stop carrier 112, while the latter is held by the aforementioned appropriate conventional wrench, to unthread the carrier from the stop and thus complete the operation of installing the stop on the main. In this connection, it will be readily understood that a service T (not shown) can be installed on the main 20 in exactly the same manner as that described for the installation of a corporation stop.

Referring now to Figures 13 to l5 of the drawings, there is shown an attachment for the drilling machine which will enable the bar 66 to be driven by power during the drilling operation and at the same time provide an automatic feed for the bar. The attachment includes a housing 214 having a somewhat dishshaped main body 216 and a top cover 218, which may be secured to the body by screws 22! extending through flanged peripheries of the cover and body. lournaled in a bearing portion 222 of the cover 218 and projecting into the housing 214 is a drive shaft 224 having a square, or other appropriate noncircular, outer end 226 projecting out of the cover for driven engagement by appropriate power means (not shown). Immediately below its square outer end portion 226, the shaft 224 is threaded for the reception of a split clamping nut 228. Preferably, a washer 230 is interposed between the nut 228 and the exterior surface of the cover 218. The other end of the shaft 226 projects through a bearing portion 232 of the body 216 and is enlarged, as at 234, to form a shoulder 236 thereon facing the inner side of the cover 218. Formed in the end of the enlarged shaft portion 234 is a socket 238 that is exposed to the exterior of the housing 214 and is of the same length as and complementary to the noncircular end portion 68 of the boring bar 60 for driving engagement therewith. The bottom of the socket 238 is provided with a circular recess or socket 24@ of slightly larger diameter than the major transverse dimension of the rod head 142 for free rotative reception thereof.

Journaled in the bearing portion 232 of the body 216 is a tubular yoke-driving sleeve 242 that is rotatably mounted on the enlarged portion 234 of the shaft and has an interior circumferential flange 244 at its inner end which overlies the shoulder 236 on the shaft 244. Preferably, an anti-friction bushing 246 is interposed between the sleeve 242 and the shaft 224 in order to facilitate free rotation therebetween. The sleeve 242 projects outwardly beyond the enlarged end 234 of the shaft and is provided therebeyond with an interior configuration or socket 248 of the same length as and complementary to the extension 96 on the base 86 of the yoke Si) for driving engagement therewith.

Within the housing 214 a large gear 250 is mounted on the sleeve 242 and secured thereon, as by a key 252, with one side of its hub portion bearing against the inner surface of the housing body. A smaller gear 254 is secured to the shaft 224 within the housing 214, as by a key 256, and at one side bears against the inner surface of the cap 213. Interposed between the inner end of the sleeve 242 and the gear 254 is a spacer washer 25S which also overlies and bears against the hub portion of the gear 250. From the foregoing construction, it will be seen that the clamp nut 228, together with the gear 254, spacer washer 258, and sleeve flange 244, serves to retain the shaft 224 and the sleeve 242 against axial movement relative to the housing 214, while the housing body 216- and the spacer washer 258 likewise retain the gear 256 against such movement. Preferably, the bearing

portions

222 and 232 of the housing 214 are provided with interior circumferential grooves having O-

rings

260 and 262 therein to serve as oil seals, while the enlarged portion 234 of the shaft has an exterior circumferential groove having an O-ring 264 therein to provide a seal between the enlarged shaft portion and the bushing 246. The housing 214 may be filled with oil through a filling opening normally closed by a threaded closure plug 266.

Iournaled in appropriate, aligned bearing

sockets

268 and 270 formed in the interior surfaces of the cover 218 and the body 216, respectively, is an idler shaft 272 offset from the drive shaft 224. A small gear 274 integral with the shaft 272 meshes with the large gear 250. A larger gear 276 is secured to the shaft 272, as by a key 27S, and has the opposite sides of its hub portion bearing against the interior surface of the cover 218 and a shoulder 280 on the idler shaft 272, respectively. The gear 276 meshes with the smaller gear 254 on the shaft 224. From the foregoing construction, it will be seen that the

gears

254, 276, 274, and 250 constitute a reduction drive for driving the sleeve 242 at a speed less than that of the shaft 224. The gear ratios are such that when the attachment is in use, as later described, the boring bar will be fed at a rate appropriate for a drilling operation.

On the upper side of the cover 118 is an upstanding lug 282 provided with a transverse bore 284 for the reception of a pivot pin (not shown) that can be retained in such bore by a thumb screw 286. This arrangement may serve to pivotally support a motor holder (not shown) on the attachment. Such motor holder may be of the type illustrated in United States Patent No. 2,651,- 222. In general, such holder may serve to properly position and hold an air motor (not shown) in position for driving engagement with the outer end 226 of the shaft 224.

In use, the attachment is positioned on top of the boring bar 6l), with the yoke 80 in its feeding position, and manipulated until the upper square end portion 68 of the bar is received, at least partially, in the socket 238 of the attachment. In the event that both

sockets

238 and 248 of the attachment are not correctly oriented with respect to the end 68 of the boring bar and the projection 96 on the yoke, the latter can be rotated slightly by hand until the yoke projection becomes properly aligned with the socket 24S in the sleeve 242. At this time, both of the

sockets

238 and 248 of the attachment will properly receive and drivingly engage the end 68 of the boring bar and the projection 96 on the yoke, respectively. The motor holder and its motor (not shown), or other type of power drive, can then be fastened to the attachment, and the motor can be operated to drive the shaft 224 to thereupon drive the boring bar 60 to drill a hole in a main. At the same time, it will be seen that the yoke Si) will be driven at a rate of speed less than that of the boring bar 60. This rate of rotation of the yoke serves to rotate the collar 84 to feed the boring bar 60 automatically at a rate appropriate for a drilling operation.

It will be evident that this power drive of the bar 60, together with the automatic feed thereof, will greatly reduce the time necessary for an operator to initially drill a main as well as greatly reduce the time necessary to comp-lete such drilling operation. After the main has been drilled by power, the attachment can be removed and the wrench 72 used to rotate the boring bar 6i? for the tapping operation. In this connection, it is Well known that a tapping operation can be carried on *aannam A It :thus will-be-seen that `the objectsj of this.v invention lhave'fbeen fullyrand'effectivelyaccomplished. 'It will be realized, however, that H'the foregoing specific `embodiment has been shown andY describedonly for the purpose of illustrating the principles of this invention and is subject to @extensive changewithout-departure from Asuch principles. Therefore, this invention includes all modications encompassed Within the spirit and scope of the following claims.

We claim:

1. In a drilling machine the combination comprising: a tubular boring bar having a tapered socket at one end thereof to receive the tapered shank of a tool, an interior shoulder facing said one bar end, and noncircular means on said bar for interfitting engagement with complementary means on the tool shank to drive the tool; a draw rod extending through said bar and having a threaded end disposed adjacent the inner end of said socket for engagement with a threaded socket in the end of the tool shank to retain the tool in said bar socket; an enlargement on said rod within said bar engageable with said interior shoulder to retain said rod in said bar; and a wrench-engageable head on the other end of said rod for bearing against the other end of said bar.

2. The structure defined in claim l including packing means between the rod and the interior of the bar.

3. In a drilling machine the combination comprising: a tubular boring bar having a tapered socket at one end thereof for receiving the shank of a tool, the inner end of said socket merging into a cylindrical bore section that terminates at its inner end in an annular shoulder; a tool having ya tapered shank receivable in said socket, the end of said shank being provided with a coaxial threaded socket; mechanically interfitting means on said bar and on said tool shank for driving said tool by said bar; a draw rod extending through said bar and having one end threadedly engaging said shank socket; a Wrenchengageable head on the other end of said rod for bearing against the other end of said bar; and an enlargement on said rod disposed in said bore section and engageable against said shoulder.

4. The structure defined in claim 3 including packing means between the enlargement and the bore section.

5. In a drilling machine the combination comprising: a tubular boring bar having a tapered socket at one end thereof to receive the tapered shank of a tool and non circular means on said bar for interitting engagement with complementary means on the tool shank to drive the tool; a draw rod extending through said bar and having a threaded end disposed adjacent the bottom of said socket for engagement with .a threaded socket in the end of the tool shank to retain the tool in said bar socket; a noncirculr head on the other end of said rod for bearing against the other end of said bar; a cylindrical enlargement on said bar adjacent said one end thereof for guiding engagement with a complementary bearing surface on the machine; and noncircular means on said bar adjacent said one end thereof for manual engagement to rotate said bar relative to said rod head.

6. In a drilling machine having a tubular boring bar provided with a noncircular configuration at one end thereof for engagement and rotation by -a wrench device and a tool-receiving socket in the other end thereof, a draw rod extending through the bar and provided with a threaded end disposed in the socket for threaded engagement with a tool to retain the latter in the socket, and a noncircular head on the other end of the rod for bearing against the one bar end, the combination comprising: means defining an upwardly facing exterior recess in a fixed part of the machine, said recess having an outer cylindrical section for snug rotative reception of the one bar end to support the bar in an upright position, while permitting the latter to be rotated manually, and an inner noncircular-section of *reduced* size complementary to andfor reception'of Vthefrodrheadto hold the rod against rotation on rotation of the bar.

7. Thestructure defined in kclaim 6 including a non-` circular enlargement on'the bar adjacent 'the socket to' provide a han'dlholdfor-facilitatingmanual rotation of `the bar.

8.1In a drilling machinehaving ia-tubular 'boring'fbar' supporting the noncircular end of the boring bar, and j said recess also having an inner noncircular section complementary to and for reception of the rod head to hold the rod against rotation on rotation of the bar.

9. In a drilling machine the combination comprising: a boring bar having a noncircular driving end and -a shoulder facing said end; a feed collar concentric with said bar and threadedly engaged With a fixed part of the machine; a yoke pivotally mounted on said collar and swingable into engagement with said shoulder to feed said bar on rotation of said collar Iand yoke, said yoke having a noncircular portion projecting toward said bar end when said yoke is engaged with said collar; and an attachment engageable with said bar end and said yoke portion to elfect automatic feed of said bar, said attachment comprising a housing, a bar-driving member journaled in said housing and having a socket accessible exteriorly thereof and complementary to said bar end for driving engagement therewith, a tubular yoke-driving member journaled in said housing concentrically about said bar-driving member and having a socket disposed outwardly beyond said bar-driving member socket and complementary to said yoke portion for driving engagement therewith, shaft means journalled in and accessible exteriorly of said housing for driven engagement by exterior driving means, means connecting said shaft means to said bar-driving member for drive of the latter by the former, and gear means journaled in said housing and connecting said shaft means to said yoke-driving member for drive o-f the latter by the former at a reduced rate from that of said bar-driving member.

10. The structure defined in claim 9 wherein the means connecting the shaft means to the bar-driving member forms a direct drive for the latter by the former.

11. The structure defined in claim 9 wherein the effective depth of the socket in the bar-driving member is greater than that of the socket in the yoke-driving member.

12. An automatic feed attachment for use with a drilling machine having a boring bar provided with a driving end, a feed collar concentric with the bar and threadedly engaged with a fixed part of the machine, a feed yoke pivotally connected to the collar and swingable into and out of engagement with a shoulder on the bar to feed the latter on rotation of the collar, the combination comprising: a housing; a bar-driving member journaled therein and having a socket exposed exteriorly thereof for drivingly engaging the driving end of the bar; a tubular yokedriving member journaled in said housing concentrically about said bar-driving member, said yoke-driving member having a portion projecting outwardly of said housing beyond said bar-driving member and shaped for interfitting driving engagement with the yoke; shaft means journalled in and accessible exteriorly of said housing for driven engagement by exterior driving means and connected to said bar-driving member for driving the latter; and gear means journaled in said housing and connecting said shaft means with said yoke-driving member to drive the latter by the former at a reduced rate from that of said bar-driving member.

11 l12 13. The structure dened in claim 12 wherein the shaft 2,291,979 Mueller et al. Aug. 4, 1942 means and the bar-driving member are of integral One- 2,499,739 Forbes Mar. 7, 1950 piece construction. 2,601,434 Du Bois June 24, 1952 2,657,604 Rueb NOV. 3, 1953 References Cited in the le of this patent 5 2,701,977 Stone Feb 15, 1955 UNITED STATES PATENTS FOREIGN PATENTS 1,280,813 Mueller et al. Oct. 8, 1918