US2368992A - Machine feed mechanism - Google Patents

Description

Feb. 6, 1945. r. H. LJUNGGREN 2,

MACHINE FEED MECHANISM 7 Filed May l5, 1942 4 Sheets-Sheet l Feb. 6, 1945. 9 T. H. LJUNGGREN 2,368,992

MACHINE FEED MECHANI SM Filed May 15, 1942 4 SheetsSheet 2 7272 a/ ym A I 1945- T. H. LJUNGGREN 2,363,992

MACHINE FEED MECHANI SM Filed May 15, 1942 4 Sheets-Sheet s Will/m.

Feb. 6, 1945.

T. H. LJuNG GREN MACHINE FEED MECHANISM 4 Sheets-Sheet 4 I Filed May 15, 1942 Patented Feb. 6, 1945 MACHINE FEED MECHANISM Thor 'H. Ljunggren, Charlestown, N. H-., assignor .to Bryant Chucking Grinder Company, Springfield, Vt., a corporation of Vermont Application May 15, 1942, Serial No. 443,114

7 Claims.

This invention relates to the feeding of work and a tool relatively, and is particularly concerned with such feeding as applied to the grinding of work. In such machines it is usual practice to produce a rapid traverse of the wheel on the work during the grinding operation.

It is an object of the present invention to present a gradual continuous relative feed motion between the Work and the wheel without interfering with and during this traverse. This feed may be produced by motion of either the work or of the wheel laterally of the line of traverse.

A further object is to produce the feed automatically at a predetermined rate and to a predetermined extent.

Still another object is to provide for automatic retraction at the end of a grinding cycle preparatory to operation on a new work piece.

For a more complete understanding of this invention reference may'be had to the accompanying drawings in which Figures 1 and 2 are top plan and fragmentary front elevations, respectively, of a grinding machine embodying one form of the invention.

Figure 1a is a detail section on line Ia-Ia Figure 1.

Figures 3 and 4 are fragmentary right han and rear elevations of the same.

Figure 5 is a detail sectional view on line 5--5 of Figure 4.

Figure 6 is a detail sectional view on line B-6 of Figure 5.

Figure 7 is a view similar to Figure 6, but showing the partsin difierent positions.

Figure 8 is a detail sectional view on line 88 of Figure 6.

Figure 9 is a fragmentary view partly in elevation and partly in section showing the traversing mechanism,

Figure 10 is a detail section on line '|Ul0 of Figure 1 showing feed as applied to the work.

Figure 11 is a detail sectional View on line ll-ll of Figure 10.

Figure 12 is a view partly in side elevation and partly in vertical section of the wheel head showing a modification of wheel feed mechanism.

Figures 13 and 14 are detail sectional views on lliles l3-I3 and |4- l4, respectively, of Figure Figure 15 is a diagrammatic view showing the control mechanism for the feed shown as applied to the mechanism of Figures 1 to 8, inclusive.

Refen'ing first to Figures 1, 2 and 3, at l is shown a machine bed having at one end a platform 2 on which is mounted for motion from front to back, a work slide 3. This work slide may have any suitable means for moving it forwardly or backwardly in case it is desired to produce a relative feed between the work and tool by motion of this head. As shown it supports work holding means indicated at 4, this means including a rotary work-carrying spindle for supporting a piece of work as at 5, this spindle being rotated as by a motor 6 carried by the casing of the work holding means 4 and connected to the spindle as by a driving belt "I. This work holding means may be adjustable angularly on the slide 3, for this purpose arcuate slots being shown at 8 for receiving suitable bolts securing the work holder holding means in position. At 9 are shown longitudinally extending slots for attachment of a suitable truing mechanism indicated generally at [0 when a grinding wheel is the tool which operates on the work.

The machine base may be provided with a rocking support at l2 on which may be carried for rocking and axial motion a tool carriage M.

This tool carriage may support a transverse slide 15 carrying a grinding wheel head 16 within which is mounted a wheel shaft ll carrying a grinding wheel I8 for operating on the work.

The spindle (I may be rotated at high speed as by means of a belt l9 passing around a pulley 20 at its rear end and connected to the drive pulley 2| of a motor 22 supported from the carriage l4. 7

This machine as so far described is of the type shown in the Arms Pat. No. 2,310,338 granted February 9, 1943, for Metal working machines and is not, per se, my invention, It is suflicient to say that the carriage I4 is moved axially to cause the wheel to traverse the'workand at the end of a grinding operation, the wheel slide is retracted into the position shown in Figures 1 and 2 to bringthe wheel out from the work,

this being accomplished by hydraulic mechaameter portion 28 which slidably fits within the tube 25 and forms a piston therefor. The shaft 21 has reduced diameter end portions 30 and 3|. center of it passes a pipe 32 which extends into the piston portion, 28 and communicates through a port 33 to the interior of the tube 25 to the right of the piston. The space outwardly of the The portion 30 is hollow and through the pipe 32 and between it and the inside of the shaft portion communicates through a port with the interior of the tube 25 at the left hand side of the piston 2-8. The shaft portion 3I is solid in cross section and is slid-ably guided through a sleeve 36 which engages a larger internal diameter portion of the tube 21 and forms a closed end to thepres sure cylinder containingthe piston 23 and zwhichitravels relative to the ,piston 28. The'rig'ht hand end of the tube 25 is open but the left hand end is closed to the tube 32. When fluid is introduced through the pipe 32 and discharged around the pipe 32 and :out.:through the pipe 37, the pressure cylinder 25 andthe tool carriage is moved to the right, while'when fluid under pressure supplied tothepipe'3Land allowed to escape through the pipe '32, "thetool slide is moved to the left or toward the work spindle.

Suitable means (not shown herein "but'"well known ,in the tart) ;mayi.be pro.vided .for control- :ling thesupplyand discharge.ofgfluidzunder pres- .sure to opposite x-sides cof the piston 23 .-.to control .the traverse 10f the grinding wheel With :reference to. the work between normalgrinding limits, 3

and .t produGe-an extendedtraverselofthe, grind- .ing wheel beyond oneof-suchdimitsoutreoperative =relation :to {the work (as at the send .of ;a grinding cycle.

.-It will betevident-that a=feed motion of the ,grinding wheel with reference to .the work :may :be :produced by rocking -the-carriage .14 about the axis -of .the tube '25, which .is :eccentrie etO -.the-workingcontaet between .the wheel and .the

work, pandrmeans .-for accomplishing the ifeedby such method is :shown .-in Figures 4 :to .8, inclusive. IIheJoed I .is; provided wi-than ;arm '4 llalong .itsiback gportion, this .-arm 40 being arranged r110 support arcamgplate A l. .As.-,shown\best in Eig- -.ures 3land4l,.thiscamgplatenlI may hezsupported adjacentetcxopposite ends onqadiustingscrews 42, landiit .imay beheld in -,adjusted p.osi-tion .as by :means of .set screws 43 threaded through .the .back wall portion 44 'of asocket .slot A5 :in .the

Stop face of Lthe arm lI), .these screws 44 bearing ragainstithe :cam plateM ande'forcing it against .theiinner walliofitheslotA-ti, ,'-I'oitherreari'extremity ,of thecarriage I4 is :se-

cured, :as bynscrews s59, spacedbrackets 5I ;hav-

ing spaced upright .fins :52, ,between which :is

theouter .endiof .theslide AD as by .the screws TBL.

.ili'he wedge ..cam .60 maybe -heldin positionas by ,a cover ,plate 19 a as .shown .inIigui-e L8, -and it .may .be secured Lto the ,=piston .rod .6 I as Joy ..a "reduced .diametier portion II of $.the -rod .extenrling throuehahole lzofithe .wedge-hamandmav- J. i

.ing a mm, .13 lthreaded on its .o1iter extremity. ='I?his,nut1'3 maysalso seourelin posttiona'lbracket I5 carrying easwitch actuating element 16 .the purpose of which wilLlater .be described.

.iI'he outer end of =.the..c,ylinder .fifisrnay-hetclosed. off as by alcylinderheadiw, andpipes .81 wandBZ leading through v,the head .39 .and the cylinder \wall, respectively, .may .be employed .to conduct fluid [under pressure .intobrv discharge fluid ,pressure fromsoppos'ite .end portions of the tcylinder beyond the piston 62. It will be noted that the end of the wedge cam adjacent to the piston rod BI is narrower than that end further remote therefrom. When the wider portion of the wedge cam bears against the block 53, as in Figure 6, the rear end of the carriage I4 is held in a somewhat elevated position with the grinding wheel forward at the start of the grinding operatiomibut as the piston is: moved .toazthe right from the position of Figure 6'to'that of Figure '7, the narrower portion of the wedge cam 60 engages the block 53, allowing the rear end porrtionrofztheqcarriage I4 to drop and moving the grinding wheel rearwardly, feeding it into the work.

Means may tie-provided as shown in Figure 15 to produce this'fee'd motion of the grinding wheel :rel-ativeztolthe'work during the operative traverse between the wheel and the work and to a predetermined extent, the wheel then being returned :to its .initial .tfeed position automatically. on .,:the extended :traversenf the wheel which brings it .-n11 t \of iqperative relationmo the work, .as .at the (end 1.01? z-a ggrinding operation, the finished work is taken .from the machine'aand an un ground-pieceaof work.-substitutedrtherefor, upon which .the.next grindin -operation is to be;periformed. ..-Referr-ing-.to .Figure 1-5, the pressure ,pipes 8| .and.-&2.leadeto:avalvecasing within which is movable a. valve 9| normally' downwardlygpressed in the:.casing SO-sasbvmeansof .aspringz92. In :the position shown in Figure 15, this piston.92 .is.1ifted .as tfar .aszpermitted by a head 93 .thereon which engages a shoulder '94 of the valve casing, and it is .heldin this position Joy fluid pressure .admittedibeneath the piston 9| as through a pipe v95 leading from a valve casing 596 within .which is :axially movable a valve .91. :In .thepositionvsho wnthis {valve 91 is .lifted .so that an :annular recess 9.8 therein opens communication to the pipevliifromapressuresupply pipe .99. When .the valve 9| :isin its upper gIJOSiitOlfl as shown, .a branch I09 leading fromithepressure-pipe. 99 communicates through .the-acasingafl around(a,-neck;portion IIJIlllof the valve 9| to the pipe 8I, while the pipe 82 .com- \municates around a valve neck IIII to thedischarge pipe I02 .havingan adjustable valve I03 ,therein by which @the, rate;of discharge-of fluid under pressure may be controlled. This causes the ,piston 62 zto'heldrivenrfrom its position of Figure 15 toward the right at a speed dependent .upon the setting of :the valve I1ll3 to produce a gradual .feedeof thergrinding wheel into thework. .Thispersists .until the .switch actuating element I6 strikes a switch arm- I05, closing ,thecontacts I I16;r and 1-01. ELhis; makes: an electricah connection from :the line 1.08, the main .switch .at I09 being closed, through the leads H40 and II-I, .the contacts 496 .and Ill! \of -:.the switch I II, throughha-ssolenoidlI2rof arelay :I-I 3,:an arm I l'4 .of this relay, ;and lleadalrlli back through :the switch I09 to the line IIB. Theactuation of the :solenoid .LI-2 throws :over the armature vswitch arm .HB .toward thee-solenoid llz breaking-ithe connectionjzo the arm .Im andclosingtaiconnectime .|.'2.D\Qf -the-solenoid .lZI tandppeninga :con-

itact =I 2 2 leading-from the lead I- I 5. contact [22 is in circuit through a lead I23 with a sole- -noid .124 .anda. lead .L25 .to \the lead I-I 0,;so zthat the :opening .of the contact 122 deenergizes the solenoid J24, .allowing the .valve .91 to :drop. thus cutting o'fi the pressure to the pipe 95 and open- .ing..-this pipe 95 toufreerdischarge through :the pip i I30. This allows .thervalveiaI \totdrop, -.cut

suitable worm gear I16 connected for rotation ting oil the pipe 8I from the pressure line I and opening the pipe 82 to this pressure line, while opening the pipeBI to the discharge pipe I 3| which by-passes the valve I03 to free discharge. Thus the piston 62 is returned rapidly to the position of Figure 15 in position to start the next cycle of operations.

After the extended traverse of the wheel slide has been produced and the slide starts back toward the work, a switchactuating element I35 on the wheel carriage depresses a switch arm I36, making" an electrical connection between the contacts I31 and I38. ,The switch actuating element I35 is free to tilt out of the way on the extended outward traverse so that at that time it does not actuate the switch arm I 36. A stop I350 holds the element I35 in position to depress the arm I36 on return of the wheel slide. This establishes an electric connection from the lead H0 and lead I39, the contacts I38 and I31, and lead I40, extending to the left hand solenoid I2I of the switch H3, and as the previous energiz'atioriof the solenoid H2 served to close the contact I20 with the switch arm II4 and lead II to the line I I6, this again energizes the solenoid I2I and re-j- Feed between the wheel and the work may bev effected, if desired, by motion of the work carriage 3 rather than'by motion of the wheel slide, and mechanism for accomplishing the feed in this manner is illustrated in Figures and 11. Referring to" the construction shown in these figures, the work slide 3 carries a bracket I50 provided with a yoke member I5I which extends rearwardly beneaththe carriage 3. The forward wall of the bracket I50 is provided with an opening within which is seated a bushing I52 and journaled therein and held against axial motion is a feed shaft; I 53 having a rearward splined extension I54. This extension projects within a feed sleeve I55 having inwardly extending portions I56 engaging in the grooves of the exterision I54 so that relative axial motion between the parts I54 and I55 is permitted while they are prevented from independent rotation. By rotating the feed shaft I53, therefore, it will be evident that the sleeve I55 will also be rotated. This sleeve I55 is externally threaded and has threaded engagement with a nut member I 59 whichis secured to the forward face of the bed I as ,by

means of screws I51 extending through ,a downwardly extending flange I58 of the nut I59 and into the forward portion of the base I. The inner wall of the yoke member I5I carries a guide block I60 having a horizontal groove I6I therein within which rides a wedge cam I62. The opposite edge of the wedge cam engages a wear piece I 63 in the inner end of the sleeve I55. The guide block IE0 is held into engagement with the wedge cam I62 and the wedge cam in engagement with the wear piece I63 by means which urges the work slide 3 forwardly in feeding direction. This as, shown is accomplished by a weight I65 fixed to the end of a cable I66 which extends through a hole I61 in the top of the base I, over a guide pulley I68 and under a guide pulley I69, both journaled in a bracket I10 secured to the top face of the bed I, and then to a post I12 depending from the work slide 3, to which post the other end of the cable is secured.

The feed shaft I 53 may carry'a hand wheel I at its outer end and it may also carry a by a worm I80 (see Figure 1a) on a transverse I80 may be lowered intoengagement with the worm wheel I16 in which case by its rotation the shaft I53 may be slowly rotated, or lifted so that I the shaft I53 may be rotated at a faster rate by rotation of the hand wheel I15. When the worm is in its lowered position itlocks the shaft I 53 against rotation by the hand Wheel I15.

The wedge cam I62 may be arranged to be traversed during the operation of the wheel (on the work to produce feed motion, this being shown as accomplished by the fluid pressure cylinder 6511. containing the piston 62a connected to the piston rod 6| a, this piston rod being provided with a shaft extension 120. extending through the cam. I62 and secured as by a nut 13a engaging the threaded outer end of the member 12a. This cylinder 65a may be connected up to-the'mechanism shown in Figure 15 in place of the cylinder 65 shown in that figure and the wedge cam I62 may be provided with an actuating. element 16a for engagement with the switch II1.

The feed may also be produced by motion of the wheel slide I6 forward or backward relative to thecarriage I4. Such an arrangement is illustrated in Figures 12 to 14. The wheel lide I5 may be provided with a depending portion 200.

which. extends down between ways 20 I upon which the slide I5 is mounted, This depending portion 200 may have fixed transversely thereof a pin 203 having a hardened head 204 which engages one edge' face of a wedge cam 205. The opposite edge of the wedge earn 205 is guided in a notch 206 of a block 201 secured to a flange 208 upstanding from the base of a channel shaped member 2I0,-the side flanges of which form the ways 20I. The slide I5 is pressed toward the flange 208 by any suitable means such as the weight 2I2 attached to a cable 2I3. This cable 2I3 passes over a guide pulley 2I4 carried by a bracket 2I5 secured to the flange 208 and is secured as'by an eye bolt 220 to the depending portion 200. Movement of the wedge cam 205 to bring its narrower portion between the members 201 and 203 permits the weight 2I2 to move the grinding wheel transverse to its axis to effect feed of the wheel with reference to the work; A switch actuating element 22I secured to thewedge cam may impinge upon the switch I I1 at, the limit of feed as in Figure 15 and the feed motion of the feed cam may be produced by the pressure cylinder 65b having the piston 62b and the piston rod 6Ib which may be connected into the system in place of the cylinder 65 and piston 62 and rod 6I of Figure 16, thus to control the cycle of the feed in the same manner that it can be controlled by rocking the wheel carriage I4 or by motion of the work carriage.

From the foregoing description of an embodiment of this invention, it should be evident to thoseskilled in the art that various changes and modifications might be made without departing from the spirit or scope of this invention.

7 I claim:

I 1. The combination with a pair of members, one of said members supporting work and the other of said members supporting a tool, moving means, connections between said moving means and one of said members causing movement of said moving means in one direction to produce melative feeding :motion lbetween 'saidr'members, sand 'infanother direction "to :produce relative re- ;traction between said members, Fa transverse wedgei'member in saidxc'onnections, means:acting to :pro'duce relativeItraverse between said memvb ers transverse i to v1 eedin'g direction, and means fo'r rzantomaticall :moving said wedge :mem-ber endwiseina rectilinear pa'th during the-traversins-action of-the too1 on the' work. I

2.-"The combination =with -a pair 0f members, "one of said members supporting work and the other of' said members supporting a tool, moving -means, connections between said moving m'eans and-one of said members causing movement "of ss'aid' moving means in one direction to produce relative feeding motion 'between'saidmembers, and in another direction to producerelative retraction between said members, a transverse wedge member in said connections, means acting to produce relative traverse between said ."mem- 'bers transverse to feeding :dire'ction, fluid pressure mechanism for movingsaid wedgemember *endwi'se in a rectilinear-path during thetraversine-action of the tool on'the work, 'and'anelec- 'triccontrol'for said fluid pressure mechanism.

- 3. Thecombination .with a pair of -members, one of said members supporting work and itlie other of said members supporting a tool, -means "for relatively reciprocating said members tocause the tool 'to' traverse the work between normal -traverse =limits, and beyond one of said limits threug'h -an 'extended traverse wherein said tool 'issspaced from the work, means for producing a 1 relative motion of saidmembers transverse'to the direction of reciprocation to causeife'e'd and re- 'traetion'of the tool relative-to the work,rlectri'cal means for controlling said feed motion-including a limit switch for stopping the feed motion'ata preda-iermined. point and setting said members =1'elatively't0 a startingfeed'position, and'switch' fisaid ream :plate rtorniove :said s'slide :in accordance with athe 'eontour of said v camaplate itoceffect :a relative sfeed E motion between work onzssaid work supporting:memberrandra toolnonusaidztool sup- :cam, a Wedge ca'm betweenisaidlfollower zandrav ,portionof isaid pivotally mounted member, wand means ifor moving-said :wedge cam to movewsaid followerrwith;referencetorsaidgpivotally:mounted membe'r. I

' i6..In combination, a base, a JibarI-rockablyiand axially 'slidable Son said base, a member :s'e'cured .to said itbar, a 1 member carried by i said base, one of said members fsupporting 'WOIk "and the "other "of :said timembers :supporting a tool 'for: operating on .sai'dxwork,r.a former'cam "carried by said base and arranged parallel ito'said bar, 'a'ffollower f for saidr'lcam imovably Icarried by "said bar-carried member, means :for lreciprocating said 'bar-icar- Irie'd rmemb'er with said '.ba'r, the angular position of said Ibar-carrled member being determined partly. by engagement :of said follower .on said former cam a Wedge'camarranged between :said cam ifollower :and bar -carried member, :and means for 'movingisaid wedge cam *to move'i'said follower with relation to :said'b-ar-"carried mem- 'ber.

7 .In combination, a-s1id'e,a yoke movable with :saidi'slicleia' fixed nut, 'a 'threadedfsleeve iarran-ged 'withi'its axis inithe direction-of motion of said nut, Ta 1 shaft isplined to and within saidfisleeve, Fa transversely arranged caml plate between one "end of said; sleeve-and said zyoke,.means pressing said being a-sIide, a'yoke movable with said slide,a

"fixed 'nut, a threaded'sleeve arranged-'inthediilyoke in a direction "to hold "said :sleeve, against said foam plategmeans fo'r rotating-said shaft to t 'move :fsaid slide, .and ameans operatively engaging said cam plate andactuable to move said cam plate transverse to :said shaft to :move 'said "slide independently a of :themotion of :said'slide fcaused byYrotation ofsaid shaft and'in accordancewith =the c'ontoimoi: said camiplate.

THOR 'ZLJUNGGREN.

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