US3073185A

US3073185A - Boring mill

Info

Publication number: US3073185A
Application number: US861002A
Authority: US
Inventors: Hoffmann Bernhard
Original assignee: Baldwin Lima Hamilton Corp
Current assignee: Baldwin Lima Hamilton Corp
Priority date: 1959-12-21
Filing date: 1959-12-21
Publication date: 1963-01-15
Anticipated expiration: 1980-01-15

Description

Jan. 15, 1963 B. Hoi-'FMANN BORING MILL 4 Sheets-Sheet l Filed Dec. 2l, 1959 H' JNVENToR.

BERNHARD HoFFMANw BY l i v @m QL @L ATTORNEYS Jan. 15, 1963 B. HOFFMANN y 3,073,185

BORING MILL 4 Sheets-Sheet 2 Filed Dec. 2l, 1959 JNVENToR. FQNHARD HOFFMANN FmiY AT TOE-N EVS Jan. 15, 1963 B. HOFFMANN 3,073,185

BORING MILL Filed Dec. 2l, 1959 4 sheets sheet 3 H YDRAU LIC CYUNDERS Eff AxLEbgAUGme Ems l sq TRAN S- TOOL 27 BOX i`|*.fT" i "T T". H ea ii- 4..1 1 L j LJ-d-u SYMCHRO CONTROL A TRANSFORMER- TOOL A @Aueme TOOL SW1-mmm@ RACK Posmmue CONTROL MOTOR SENSE CONVERTER AND D. c. 7 ELECTRIC AM PMR/l HYDRAUUC REVEEEVE@ CYUNDER Mum-TURN POTENTIOMETEE Fora HNE TOOL ADJUSTMENT QM @E ATTORN Eys Jan. 15, 1963 B. HOFFMANN 3,073,185

BORING MILL Filed Dec. 2l, 1959 4 Sheets-Sheet 4 INVENTOA BERNHARD HOFFMANN United States Patent vO 3,073,185 BORING MILL Bernhard Homann, Hamilton, Ohio, assigner to Baldwin- Lima-Hamilton Corporation, Hamilton, Ohio, a corporation of Pennsylvania Filed Dec. 21, 1959, Ser. No. 861,002 3 Claims. (Cl. 77-4) The present invention relates broadly to boring mills, and, more specilically, to an improvement in a car wheel boring machine which sets the radius of the boring tools automatically.

In present day practice the boring of car wheels, whether they be of cast iron or steel, has been greatly simplified due to the various automatic features that have been incorporated into wheel boring machines of the hydraulic type. These machines have been designed to such a degree of versatility that the car wheel is automatically chucked and then bored by roughing and finishing cutters and chamfered in the'same series of operations. Furthermore, during said operations the machine is designed to be fed at dilerent speeds with the speed changes being automatic-between the rough cutting, finish cutting, chamtering and tool withdrawal operations. Thus, the operations of such a machine are substantially continuous and automatic, resulting in maximum'production, yet requiring a minimum of time Iand effort on the part of the operator. t

At the present time, in finishing carl wheels preparatory to mounting them upon axles, it ,i'sfne'cessary to .measure the diameter of the axle to be fitted with a conventional'-,

micrometer-and then bore the hub opening inthe car wheel to the proper diam-eter, which is usually @slightly less than the diameter of the, axle, so that .thefwliee'l will have a drive vfit on the axle. The practice by the railroadsof refinishing car wheels embodiessubstantially the. same 'op-u erations as employed in finishing new car wheels, in that,

the Wheel is removed from the axle and the bore of the car wheel is then refinished preparatory to mounting ,said wheel upon a new or a relinished axle. It is, however, necessary that a skilled machinist measure the diameter of the new axle with a micrometer, adjust the cutters so as to bore a hole the idiameter of which shall-be slightly'lessthan the diameter of the axle in order to ensure that the wheel will havefa proper drive fit when mountedupon said axle.

urements be taken of one part and manually transferred to another part in setting up the boring mill. lWhile the boring and chamfering operations are automatically .performed "by the borin'g mill machine, the measurements necessary for properly positioning the cutting` tools dependsupon a correct and accurate measurement being obtained by aimachinist, which always brings into being the possibility of an error developing that could result in the entire Wheel being improperly bored and thus subject to being scrapped.

One of the objects of the present invention is to provide a car wheel boring machine that is automatic in operation for boring the hubs of a car wheel.. v l

Another object is to provide a car wheel boring machine having a boring bar with tools adjustably mounted therein Aand means for adjusting said tools radially of the boring bar commensurate with the. diameter of an axle upon which the car wheel is to be mounted.

Another object is to provide a car Wheel boring ma-- chine having a vertically reciprocating boring bar with adjustable cutting tools carried thereby and motor means disposed within said boring bar for radially adjusting said cutting tools dependent upon the diameter which the car wheel is to be mounted.

While the-foregoingtype of operation hasy proven 'to b esatisfactory'and acceptable, it .does require that measof an axle upon ice Other objects and advantages, more or less ancillary to the foregoing, in the manner in which all of the various objects are realized, will appear in the following description which, when considered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention.

Referring to the drawings, wherein the preferred embodiment of the invention is illustrated:

FIG. l is a fragmentary vertical sectional view of a car Wheel boring machine embodying the present invention incorporating a `diagrammatic representation of an axle gauging mechanism associated therewith;

FIG. 2 is an enlarged fragmentary detailed sectional view of the lower portion of the boring bar with the cutting tools disposed therein, the section lbeing taken on tion of an axle gauging station withaxle centering wings,v

in position to receive an axle to be'gauged; and

FIG. 7 is a fragmentary view of the parts shown 1in, FIG. 6 with the centering wings. yclosed about an axle,t andthe gauging feeler in its sensing position.

Referring to FIG. 1, ..there is s hown va table 10 that -is rotatably mounted'upon a bedofa conventional boring machine, such as thet'ype. disclosed'in:Patent'2,6l9,854z

of December 2, 1 95'2,` to Schu-rr. rotatable 'table 1`0f has mounted, fon the Upper face thereof,- a plurality of spaced ychuck jaws 11 that are slidably supporte d upo suitable .guide members, not shown,iwh;ich extendradi of the table 10. The chuck jaws.1'1 areadapted 'to engag, and retain a car wheel 12 in proper position to have worlg` operations Aperformed thereon by suitable boring bars. A frame 14 is adapted to be supportedby. the' bedof the boring machine and it, inturnycarr'ies a cylindrical,

guidefl'Sin which is mounted a verticalboring bar '15 The frame 14 also has v`mounted thereon af hydraulicf motor which is. adapted to operate the bor-ing bar 16 in avertical reciprocatory manner within; the Aguide 15. T hej hydraulic motor 17 consists of a piston 18 operatingyyith,

a cylinder 19 and having a c'onnecting'rod 20 mounted,}

thereon which is turn connects the piston with. the boring` bar, 16 through the. connecting member 21. A The` hydr lic motor 17 is provided with inlet and outlet connections..

-22 at each end thereof, which are adapted tol be connected to a suitable hydraulic pump, notvshown, for the delivery of uid under pressure to cause ,reciprocation of the piston, 1 8 withi'ril the cylinder 1'9 and the resultant movement of the boring lbar 1-6. Such mechanism is conventional in the art. i x 4 The hollow v boring bar 16 has mounted in the upper; portion thereof, in any suitable manner, a reversible motor 24.v The reversible driving motor 24 has a conventional nut drive which engages a splined screw (not shown) to cause a reciprocation of a shaft member 25. The direction of reciprocation of the shaft member depends on the direction of rotation of the motor 24. The reciprocatingshaft member 25 carries or is drivingly connected with a rack member 25a whichextends substantially theme11-,l

. tire length of the boringv bar 16 with the lower end of thefn rack member projectingat an extreme of its movement into a suitable cap or housing 26 provided on the bottom or lower face of the boring bar. The rack member 25a` is supported by suitable bearing members 27 provided at'y 'l spaced points within the lower end of the boring bar 1'6 to insure its proper alignment within the boring bar and its engagement vvith'the driving means of the motor 24;

The boring bar 16 is provided with three cutting tools, with the lowermost tool 28Y being a rough boring tool, while ajnishing boring tool 29 is disposed midway between'pthe'roughboring tool '28 and a chamfering tool 30. The three tools are radially adjustable within the boring bar'l. In the form of adjustment 'shown in the drawings, each of the tools has associated therewith a spurv pinion which isy adapted to engage the rack member a so that upon reciprocatorymovement of the rack member, the spury pinions 32 will be rotated to either advance or retract the toolsradially vof the boring bar. The three cutting tools carried by the boring bar 16 are mounted therein for adjustment in thesame identical manner; thus, a description `with respect to one ofthe tools will readily apply'to the others.

"Asashown in FIGS. 2 and 3, the boring bar 16 is provided with adiametricallyV extending passageway or hole 33 which opens out through the opposite sides of the boring bar. The passageway 33 has slidably mounted therein appair of

tool carriers

34 and 35 which have their outerendsformed to receive" the desired replaceable cut.-

ting tools '36. Each tool carrier is providedv with an intdrnally threaded 'socket 37 which extends from its inner end short of its outer end, and when the tool carriers are mounted in longitudinal alignment for` placement in the passageway 33,'the same are connected by a double ended,

adjustable screw member 3.8'. One end of the screw member 38 is provided with left-hand threads and the other end of the'v screw member isprovide'd with' rightfhand threads, and "thescrew, rnerriberl is threaded into theA threaded sockets 3 7 formed -irr the

carriers

34 and 35. d ,Y

ejc'e'ntral portion of theV screw member 38, FIG. 3, hastlie above-mentioned spurpinion 32 mounted thereon for engagement with the rack .member 25a', 'soA that upon reciprocatory movement of the rack member 25a the spur pinionA 32frwill bev rotated in a complementary direction which in turn'pwill rotate the screw member 38 causing the tool holders 34l and 35 to be either retracted or advanced radially ofthe boring bar16' depending on the direction of movement of the rack 25a. By providing threads of appropriate pitch on the screw member 3S and socket 37, the cutting members are capable of being radially adrvancedl or'retracted v to a degree complemental to the degr'ee of reciprocatory movement of the rack` member and the rotative movement of the spur pinion 32.

The boring bar 16 is'provided with a passage 40, FIG.

3, that 'is transverse of the` passageway 33 and adaptedv toiriteifs'ect said'passageway so that the bearing members ZTmay be mounted within the boring bar 16 and retained therein' by cap sc reit'ls 41 to insure the retention of the rack member irr'engagement with the" spur pinion 32. As i sho` n in FIG. 2,` the tool 'holders'34 and 35 areretainedv 1n`f 'd passageway 33 by means of adjustable wedges 43 which'v 'are held in* engagement with one another by a screw member 44, so that said wedges 43 will insure the ret'etionof the tool carriers within the passageway 33 o`f`tliefboring bar 16, yet vstill permit the tool carriers to have a radially adjusting movement within the cutting barv upon vthe. rotativel movement Aof the screw member 38. 'lhel removal of the screwfm'ember 44 enables the wedges 43` to..be withdrawn, thereby 'permitting the to'ol carriers 34; and 35 to; be' removed from the boring bar as a unit` so that the tool carriers can be replaced.

The presentY invention `is particularlyV directed to. the combination of, elementsgwhich causes an adjusting actuationv of;v the tool adjusting motorY 24 by tn eans'ofl which theradial positions of both the roughing tools 28 and the l tools v'2.9, are .setvr to the proper dimension. As previo l no ted', .the1 size of the boreiinished by thesel tools iside Y xleinc'zles the usual bearing area,

ed. by automatically gauging an `vaxle on which .i

d wheeiistto, be drives.4 An eine to be need with n ted generally in FIGUREY l and. in. Y 75 dust guard and wheel seat at each end. Since the present invention is concerned only with a machine which will automatically bore a set of wheels to fit the wheel seat of a given axle, no detailed disclosure of the axle itself need be made.

The axle A is received on a measuring fixture in any suitable manner, and the sequence of operations hereinafter described starts at this point. Referring to FIGS. 6 and 7, the axle A is permitted to roll down an incline to a point where it overrides an actuating switch which controls, in any suitable manner, the hydraulic circuit to a wing actuating cylinder 51. The piston within the cylinder 51 is moved downwardly by the hydraulic force of the cylinder and causes a slide 52 to move downwardly. The slide has pivoted thereto a pair of

axle engaging wings

53 and 54 in the form of bell crank levers pivoted to a stationary portion of the mechanism at 55 and 56 respectively. Thus, as soon as the axle A passes the actuating switch 50, the Wings commence to move in and to clamp the axle in the centered position shown in FIG. 7.

As can be seen in FIG. 7, the axle engaging wing 53 carries a small pin 57 which engages the axle when the wing is in its fully closed position. This pin is forced to the left by engagement with the axle and closes an actuating switch 58 which starts the tool gauging mechanism in operation.

Closing the switch 58l actuates the hydraulic circuit of a cylinder 59 connected to an axlegauging rack 60. The rack is attached directly or indirectly to the piston which is within the cylinderl 59, and the rack carries at its nose portion a feeler member 61 which engages the wheel seat of the axle as shown in FIGS.k 1 and `6.

Meshed with the rack 60* is a pinion gear 62 which is carried by the shaft of a synchro transmitter 63 so that the armature offthe transmitter vis rotated as the rack moves in towards the axle, and the extent of its rotation willv be determined by the extent of the movement necessary for the feeler 61 tok engagev the wheel seat of the axle.

A synchro follower 64 is electrically connected to the transmitter 63l and, .of course, follows its movements so thatl the angular movement of the follower is precisely the same as the angular movement of the transmitter.

As will be seen from FIG. 4, the follower 64 carries a pinion 65 which is in meshing engagement with a follower rack 66. This assembly is carried by the boring bar housing and projects through the side wall thereof ina suitable bearing 67. The follower rack 66 has a tool engaging feeler 68 on its inner end so located as to engage the cutting edge of the finishing tool 29 as best shown inv FIG. 2..'I`he rack 66 is moved inwardly by a vhydraulic cylinder 69 to the point where the feeler 68A engages lthe' tool.

It should be` assumed that the resetting of the tools v starts with the tools in their innermost position each'time is energized to bring the finishing tool 29to `the Yradially outward position in which contact with the `feeler 68 is made after-which the motor continues to operate so long as'an imbalance exists betweenthe angular position of the sensing synchro 63 and the follower synchro y64. The

unbalancing signal is suitably amplified and y'fed to the.

motor 24 asA` an Voperating voltage in a`known manner.

The outward movement of the tool'against the feelei" 68 takes place'v against the pressureof the fluid in cylinderl 69, andthis movement' corrects the position of the follow'-VIA er synchro 64 by actuating" pinion 65 Vthroug'l'l rack" Y66.V

wheel of the proper diameter to receive an axle of the size that is then engaged by the feeler of the synchro transmitter 63.

Obviously, movement of the rack 25a to adjust the iinishing tool 29 to the proper radial position simultaneously causes a radial adjusting movement of the roughing tool 28 and the chamfering tool 30. The tools are then in an adjusted position and the roughing and iinish cut of a wheel blank placed on the machine will exactly coincide with the dimension established by the feeler 68 which, in turn, coincides with the dimension of the axle A established by the gauging tool feeler member 61.

The boring tools having been properly positioned radially by the action of the motor 24 through the rack mechanism 25a described above, a car wheel 12 is placed upon the chuck jaws 11 mounted on the rotatable machine table 10, and the vertical boring bar 16 is moved downwardly in a conventional manner to bring iirst the rough boring tool 28 into engagement with the car wheel. After the rough boring operation, the iinishing tool 29 is brought into position and the bore finished. As above noted, the action of the boring bar is conventional and is caused by piston 18 moving downwardly within cylinder 19. When the nishing tool 29 has passed through the bore of the wheel hub, the chamfering tools 30 are subsequently brought into engagement with the edge of the car wheel hub to impart a chamfer to the hole which has been previously machined by the rough and finished boring tools. The downward movement or stroke of the boring bar 16 and the degree or depth of cut of the chamfering tool 30 is determined by an adjustable stop rod 48 carried in the boring bar guide 15. The stop rod 48 is provided with an adjustable mechanism 49 for positioning the upper end of the stop rod to engage an outwardly projecting abutment formed on or carried by the upper end portion of the hollow boring bar 16. Thus, with the stop rod outwardly positioned by the adjusting mechanism 49, the abutment 49a on the hollow boring bar 16 will engage the upper end of the rod 48 thus stopping the movement of the boring bar and of the chamfering tool 30. The stopping of the downward movement of the boring bar causes the hydraulic motor 17 to be reversed so that the piston 18 will be moved upwardly. This reversal of movement at the end of the machine operation is conventional. In the case of the present invention, the upward movement of the boring bar is accompanied by an inward movement of the tools, so that by the time the boring bar has reversed to the point that the finishing tool would pass through the hole that has been previously bored, the tools have been retracted by energizing the motor 24 and the finishing and roughing tools can both pass through the bored hub so that the hub will not be scored as sometimes occurs with conventional machines.

The upward movement of the boring bar and the inward movement of the tools continue until a limit switch 70, which can take any suitable form, is actuated by some such means as a depression 71 in the boring bar body. When the limit switch drops into the depression the upward movement of the boring bar is stopped and the parts are ready for a new setting. 'I'he limit switch 7i) is wired to act as an interlock, in any suitable manner, so that no energy can pass into or out of the synchros, and no adjusting movement of the

racks

60 and 66 can be made until the boring bar is in such a position that the finishing tool 29 is opposite the feeler FIG. 5 indicates diagrammatically a system in which two wheel seats are gauged consecutively so that a pair of wheels will be produced for the `axle A. It may be desirable, in some instances, to use a single axle gauging mechanism and to transport this mechanism from one wheel seat to the other. If desired, however, duplicate axle gauging devices can be provided and con- 6;. nected to an appropriate switching mechanism so that onev or the other will close the circuit to the follower synchro 64 and its associated rack 66.

No attempt has been made in the present specication to show the exact electrical circuits or hydraulic circuit involved since these are well known in the art. While various of the elements are shown diagrammatically, various modiications and changes will suggest themselves to those skilled in the art, and such modifications may be ma-de without departing from the scope of the appended claims. l

What I claim is:

l. In a boring mill having a rotatable table for supporting a car wheel or the like, a hollow boring bar positioned in a plane transverse to said table for engagement with said car wheel, motor means associated with said boring bar for advancing and retracting said boring bar with respect to said car Wheel, means for providing relative rotatable movement between said boring bar and the car wheel, a plurality of tools slidably mounted for radial adjustment in said boring bar, means mounted in said boring lbar for reciprocatory movement therein and engageable with said tools |for radially advancing and retracting said tools with respect to said boring bar, means connected to said reciprocatory means for driving said reciprocatory means, feeler means, means for lineally moving said feeler means into contact with an axle on which the car wheel is to be mounted, centering means for positioning the axle centrally in the path of s aid feeler means, switch means actuated by said centering means when the axle is `centered to actuate said feeler moving means to move said feeler means into contact with the axle, and means responsive to said feeler means for energizing said drive means to advance said tools radially to a position such that the diameter of a hole drilled thereby in the car wheel bears a predetermined relationship to a diameter of the axle.

2. In a boring mill having a frame and a rotatable Itable ifor supporting a car wheel or the like, a guide carried by said frame, a hollow 4boring bar mounted in said guide for reciprocatory movement into and out of engagement with said car wheel, a hydraulic motor mounted on said frame and engageable with said boring bar for actuating same, a reciprocatory rack member mounted in said boring bar, a motor in said boring bar, driving means carried by said motor and engageable with said rack member, said boring bar having an opening therethrough, a pair of radially disposed spaced cutters slidably mounted in said opening and provided with opposed axially aligned internally rig-ht and left hand threaded bores, a spur pinion mounted in ysaid opening between said ycutters and having right and left hand threaded extensions on opposite sides thereof engaging the threads in said bores, said rack member engaging said spur pinion for radially advancing and retracting said cutters with respect to said boring bar upon the movement of said rack member, means including a synchro transmitter to sense Ithe diameter of an axle to which a wheel is to be fitted, a synchro follower actuated means to gauge the radial position of one orf said tools to bore a wheel to a diameter established by said synchro transmitter, and connecting means between said motor and said synchro follower to advance said tools radially of said boring bar to the position established by said synchro transmitter.

3. In a boring mill having a rotatable table for supporting a car wheel or the like, a hollow boring bar positioned in a plane transverse to said table for engagement with said car wheel, means associated with said boring bar for advancing and retracting said boring bar with respect to said car wheel, a plurality of tools slidably mounted for radial adjustment in said boring bar, means reciprocally mounted in said boring bar and engageable with said tools for advancing and retracting said tools radially of the boring bar, a motor mounted in said boring bar, driving meansl carried by said motori and engageable with said reciprocally-mounted means, first eeler means adjustable to adiameter of an axle to which a kWheel is to be tted, rst responsive means responsive to the position of said feeler means, second lfeeler means, means for moving said second feeler means into contact with one of said tools, second responsive means responsive to the position of said second feeler means and cooperatingwith said irst responsive means to gauge the radial position of said one tool yto bore a wheel to a diameter established by said rst responsive means, and connecting means between said motor and said second responsive means to advance said tools radially of said boring bar to the position established by said first responsive means.

References Cited in the le of this patent UNITED STATES PATENTS Harden Oct. 22, 1895 WoytychA Feb. 2, 1937 Nye June 23, 1942 Christman July 23, 1946 Trornov Jan. 22, 1957 Hennessy Oct. 15, 1957 Townsend Mar. 18, 1958 Wagner et al. July 22, 1958 Wor-then Dec. 30, 1958 f Howey etal July 19, 1960 FOREIGN PATENTSr Great Britain Sept. 10, 1940

Claims

3. IN A BORING MILL HAVING A ROTATABLE TABLE FOR SUPPORTING A CAR WHEEL OR THE LIKE, A HOLLOW BORING BAR POSITIONED IN A PLANE TRANSVERSE TO SAID TABLE FOR ENGAGEMENT WITH SAID CAR WHEEL, MEANS ASSOCIATED WITH SAID BORING BAR FOR ADVANCING AND RETRACTING SAID BORING BAR WITH RESPECT TO SAID CAR WHEEL, A PLURALITY OF TOOLS SLIDABLY MOUNTED FOR RADIAL ADJUSTMENT IN SAID BORING BAR, MEANS RECIPROCALLY MOUNTED IN SAID BORING BAR AND ENGAGEABLE WITH SAID TOOLS FOR ADVANCING AND RETRACTING SAID TOOLS RADIALLY OF THE BORING BAR, A MOTOR MOUNTED IN SAID BORING BAR, DRIVING MEANS CARRIED BY SAID MOTOR AND ENGAGEABLE WITH SAID RECIPROCALLY-MOUNTED MEANS, FIRST FEELER MEANS ADJUSTABLE TO A DIAMETER OF AN AXLE TO WHICH A WHEEL IS TO BE FITTED, FIRST RESPONSIVE MEANS RESPONSIVE TO THE POSITION OF SAID FEELER MEANS, SECOND FEELER MEANS, MEANS FOR MOVING SAID SECOND FEELER MEANS INTO CONTACT WITH ONE OF SAID TOOLS, SECOND RESPONSIVE MEANS RESPONSIVE TO THE POSITION OF SAID SECOND FEELER MEANS AND COOPERATING WITH SAID FIRST RESPONSIVE MEANS TO GAUGE THE RADIAL POSITION OF SAID ONE TOOL TO BORE A WHEEL TO A DIAMETER ESTABLISHED BY SAID FIRST RESPONSIVE MEANS, AND CONNECTING MEANS BETWEEN SAID MOTOR AND SAID SECOND RESPONSIVE MEANS TO ADVANCE SAID TOOLS RADIALLY OF SAID BORING BAR TO THE POSITION ESTABLISHED BY SAID FIRST RESPONSIVE MEANS.