US1717899A - A corpo - Google Patents

Description

June 18, 1929. G. n. suNDsTRANb 1,717,899

GRIND'ING MACHINE Filed March 30, 1925 8 Sheets-Sheet l GRINDING MACHINE lFiled March 50, 1925 8 Sheets-Shea*I 2 June 18 l929 l G. D. sUNnsTRAND 1.717.899-

GRINDING MACHINE Filed March 50, 1925 8 Sheets-Sheet 3 .lune 18, 1929. G. D. suNDs'rRAND n GRINDING MACHINE 8 Sheets-Sheet 4 Filed March 30, 1925 .Il lllll llllllllllllll .lm/ia, 1929.

G. D. suNDsTRAND 1,717.899

. GRIND'ING MACHINE Filed March 30, 1925 8 Sheets-Sheet 5 June 18, 1929. G. D. sUNDs'rRAND GRINDING MACHINE 8 Sheets-Sheet 6 `Filed March 30, 1925 June 18, 1929. G, D SUNDSTRAND 1,717,899

GRINDING MACHINE FiledvMarch 30, 1925 8 Sheets-Sheet '7 lll June 18, 1929. G, D. sUNDsTRAND 1,717,899

GRINDING'MAGHINE Filed March 30', 1925 8 Sheets-Sheet 8 Patented June 18, 1929.

UNITED STATES PATENT OFFICE.

GUSTAF DAVID SUNDSTR-AND, F ROCKFORD, ILLINOIS, ASSIGNOR, BY MESNE ASSIGN- MENTS. TO SUNDSTRAND MACHINE TOOL OO.7 OF yISOCKFORD, ILLINOIS, A CORPO- RATION 0F ILLINOIS.

GRINDING MACHINE.

Application filed March 30, 1925.

This invention relates to grinding machines and particularly to a universal grinding machine involvingl means for grinding circularl arcs and surfaces of a large radius. The grinding machine art abounds with various universalv machines, but those which are equipped for radius grinding are few in number and are at the most large and cumbersome, occupying considerable floor space becauso of the provision of the radial grinding mechanism. Such machines Iare usually specially adapted for radial grinding and are not generally adapted for other common forms of grinding work. A radius grinder is a specially valuable machine for use in a railroad shop where the linksl of locomotives are ground, so that by provi-ding other facilities in the machine, the radius grinder is not only special equipment, but is also useful uni- \.fersally.

It .is an object of the present invention to provide a universal machine of the character above referred to which is especially adapted for use in railroad shops.

It is a particular object of the invention to provide a novel arrangement permitting the grinding of circular arcs with a large radius.

It is another object of the invention to provide a machine in which the radial grinding members occupy very little floor space.

A. still further object of the invention to provide aradius bar in the machine which vertically suspended from a rigid upright extension of the base.

Another object of the invention is to provide a horizontally movable work carriage which operates in conjunction with the radius bar to produce an arcuate path for Athe work passt a grinding wheel.

a planetary motion for the grinding spindle.

A still further object is to provide a particiilar type of planetary mounting to permit adjustment of eccentricity of the spindle from aero to a maximum.

Serial No. 19,198.

Still other and ancillary objects will appear f in the ensuing description.

.3y providing a machine capable of carrying out the foregoing objects I may produce a. universal grinding machine suitable for radius grinding, internal grinding, surface grinding, and cylindrical grinding.

In the accompanyin drawings I have illustrated a machine embodying the principles of the invention which fullilsall the foregoing objects and which has other and ancillary advantages as will be appa-rent from the ensuing description.

In the drawings, Figure 1 isa front elevation showing the front of the work base and the end of the grinder spindle base.

F 2 is a side elevation looking toward the right in Fig. l, showing the end of the work base and the front of the grinder spindle base.

Fig. 8 is a plan section taken approximately on the line of Figs. land 2 showing the important features relating to power distribution.

Fig. i is an enlarged front elevation of the work base showing the mechanism in the gear box in cross section and showing a piece of work set for radius grinding.

Fig. 5 is a vertical cross section of the work base taken approximately on the line 5 5 of Fig. 4 showing' the construction of the work table and of the work carrier and the automatic drive mechanism for the table.

Fig. 6 is a side elevation of the spindle base showing' power drives in dotted lines and showing a cross section of the gearbox.

Fig. 7 is a front elevation of the end of the spindle base showing another cross section of the feeding mechanism in the gear box, the power drives, and the coolant pump.

Fig. 8 is a cross section of the spindle casing and of the parts showing the arrangement for the. planetary drive, the cross section being taken along the line 8 8 of Fig. 10.

Fig. 9 is a detail cross section online 9-9 of Fi g. 8 showing the interior of the spindle casing and the vertical. feeding means therefor.

Fi g. 10 is a cross section of the front end of the spindle casing on the line 10-10 of Fig. S showin the planetary drive and planetary adjustment.

Fi 1l (Sheet il) shows a. detail vi ew of the power connection `used in the planetary drive, the view being an enlarged portion of a corresponding part in Fig. 1.

Figs. 12 and 13 (Sheet 4) represent front and side views of a locking device for the work table.

Fig. 14 (Sheet 7) is a diagrammatic explanation of the radiusgrinding principle.

General dcsmn'ptz'on.

The machine illustrated in thev drawings Acomprises generally a horizontally movable grinding wheel carriage and a horizontally movable work table or carriage Each of said carriages `has vertical ways thereon upon Vwhich the wheel head and the work are vertically adjustable and movable. A radius arm is pivotally connected tothe machine frame and to a work carrier which is movable on vertical ways on the work table. By'tliis construction the horizontal reciprocation ofthe work table produces a verticalreciprocation oflth'e verticalwork carrier, the. two motions being't-hus compounded into a single arcuate motion resulting from a harmonic motion lvertically with respect to uniform motion horizontally. y y The grinding wheel carriage is equipped to have an automatic reciprocating,motion and in addition a continuous oscillatory `motion superimposed upon the reciprocation. It is lfurther provided `with other adjustments for horizontal and vertical positioning of the wheel with relation tothe work. In addition the grinding spindle'has a planetary drive, and an adjustment whereby the spindle may be offset a predetermined distance from a given axis land thereuponrevolved in `an orbit about said axis. These features adapt this yportion ofthe machine for universal grindtical work. carrier thereon are equipped toreceive and to hold work bythe application of suitable Yfixtures thus adapting the machine to hold'work in that position'best suitable Ifor location with lrespectto the grinding wheel for any particular operation.

Base anrlpowcr distribution.

Referring particularly to themaehine illustrated in the drawings there is shown a machine supported bya base substantially inthe form of a cross (li ig. 3). The'base comprises preferably a pluralityV of sections as 10, 11 and 12 ('Fig 3) which are boltedvtogether. The base section supports the work carriage. The base section v11 is inreality an 'upright column, the upper portion of which .has two rectangularly arranged faces 13 and 14, tapering'toward Vtheir common edge at thetop. This column provides a rigid support for the upper end of the radius'bar.

The base 12 supports the grinding wheel carriage and carries its'related'mechanism. Ancillary structures 'are suitably arranged in the assembly unitfto interrelate the principal parts of the machine "foruniversal coopera- 4Boththe horizontal work table and-the verf-y tion to provide a machine of the character desired.

The machine is preferably self-contained and to this end is provided with a motor 15 (Figs. 1., 2 and 4) carried by `a bracket 15a (F ig. at) on the column 11. A main drive shaft 16 (Fig. 3) is provided nea-r thebottom of the machine from which a grinding wheel is indirectly driven andthe carriages are fed. The shaft 16 carries a power receiving pulley 17 driven by a belt 18 from the motor. i

The shaft has its driven end suitably supported transversely through the base section `l() by bearing 19, while the other end bears in a supporting arm 2O secured to the end face of base section 12. A wide pulley 21 is carried by the shaft adjacent to said arm for a belt drive to the grinding` wheel. For travelling the two carriages the countershaft 22 .is provided transversely to the main shaft, intermeshing` helical gears 23 and 24'being provided on said shafts, as shown in Figs. 2, 3 and 6. .This countershaft 22 is provided with a pulley 25 for driving a pump 26, a

on this shaft connects by means' of belt eo to another part of the grinder carriage mechanism. This last mentioned mechanism cffects the reciprocal motion of the ygrinding wheel while the shaft 31 effects the reciprocal motion of the work. It will be understood, of course, `that other means of .power distribution may be employed.

T he parts hereinabove referred to disclose but one power shaft 31 to the work end of the machine while therehave been disclosed three power driven movements to the grinding wheel end, namely. the main shaft pulley 21, the bevel gear 27 on counter-shaft 22. and the pulley 32 on the second countershaft 31. These three power sources operate independently upon the grinding wheel. each one, however, being capable of governing the motion thereof in a predetermined manner. main pulley 21 effects rotation of the grinding wheel as well as a planetary motion to the wheel spindle. 'll he bevel gear effects a` continuous oscillatory motion of the wheel axially of the spindle to prevent uneven wear ofthe grinding surface. Ther pulley 32 effects the automatic reciprocal travel of the grinding wheel axially thereof into and out of or along the work.

Grinding cti/rcel mounting.

The structure ofthe grindiu g wheel mounting herein disclosed con'iprises a horizontal carriage 3/1 (Figs` 1, 2 and G)V movable on ways 35 at the top of the base section 12. This carriage bears an upright head 36 which is The Y ist Cil

provided with parallel vertical ways 37 upon which. slides the spindle mountingl or casingJ 38 shown in detail in Fig. S. l Vertical adjustment is obtained by any suitable means as, for example, a lixed `worm screw 39 (Fles. 2, 8 and carried in the upright head 36 and the bevel gear-nut el() tlireaded thereon and rotatably lixed in a bracket eil carried by the spindle casing 36. Nut all is rotated in its bracket by the bevel `gear on shalt i3 which carries the hand wheel 44 by which vertical adjustment is effected.

The spindle employed may have any Well known construction. However. for lthe purposes described I prefer to provide a spindle which has a planetary motion, the same being placed eceentrically in the casing 3S, and I :further provide means to eil'feet an adjustment in the eecentricity from Zero to a maximum. Sueh a construction provides a machine which is more iniiversal in character than Would follow from the provision ot a lixed spindle. Herein in l? S41 l illustrate a suitable type of planetary mechanism contained within the casing 36. A suitable shaft 45 is adapted for driving;A a grinding' wheel f4.6 at one end thereof, a small wheel 46 being herein shown. The shaft 4:5 belt driven over the pulley 47 at one end thereof. The gi'iindingwheel spindle is preferably made in two separable sections in axial aliiiement, one section being;I the shaft 45 and the other being a removable sect-ion 4.6 to provide for using` various types olE `grindingr heads on the casingr 38. The removable spindle section 48 carries the wheel 46 and ab uts the spindle section l5 in a universal slot and key joint 49. Shaft 45 is eceentrically and .rotatably mounted in a shell member 50, suitable anti-friction bearings 5l and 52 beiner provided at each end et the spindle. Shaft TLS rotatably mounted in a removable casing' or head 53 which has a cylindri lal, j'irojection 54; thereon fittingy into a corresponding recess eccentric ot the shell 50. The end of projection 54 and the recess are threaded as at 55 Ato secure a tight init of the parts. The shell 5() is also eccentrieally and rotatably mounted in a housing or sleeve 56 which is rotatable with respect to Vthe casingl 5S, the axis of rotation of housingl 56 being` coaxial to the casing 38 (Fig. 9). The dislance oil-center of the spindle in shell 50 the same as the distance oil-center of shell 56. in housing 56; By this arrangement the eccentricity of the spindle with respect to member 56 (and hence the casing 38) becomes variable Afrom Zero to a .maximum accordingr as the shell 5() turned relative to the housing 56. Theseitore7 in one position olli the spindle (Figa. 9 and l0) the spindle 45 is centered with the axis oit the housing' 56 because the eccen'trieities neutralize each other, While in Yanother position (Fig. 9) the spindle indicated in dotted line has a maximum eccentrieity produced by turning shell 50 i800 about its axis from the neutral or 'full line position indicated.

Means is iurther provided to eliect a variation o'l2 the eecentricity by rotation oli the shell 50 with respect toits housing member 56. This means comprises a vworn'i gear 57 fixed to the shell 5l) and a worm pinion 56 iiriuesh therewith carried by the housing member 56 by bracluits 56a in which the pinion is rotatable. A. pair oit bevel gears 5S) and 60, one on the j iiinion7 andthe other rotatably carried in the :tace ot the housing ineinber 56 and tilted on a shaft 6l, serves to eliect the adjustment by turning` oli the shaft. .Shaft 6l provided with suitable means as a key or thumb screw 62 (Fig. for this adjustment of spindle eccentricity.

When the spindle is used in its eccentric adjustment, the housing' 56 must be rotated to secure the desired planetary motion. Means is prmfided ior doing); this from a power drive throrurh the :following described. nufchanisiu: Pulley (3S-l (Figs. l, 2 and l1) receives power trom the belt Gel. A short stub shaft 65 carries the pulley 63 and transmits power to a parallel shaft 66 on easiiu;l 38 through a short vertical shaft 67. 'lWo sets oit helical gears indicated by immerals 68 and 6E) malte the power connections thrmigh shafts 65, 67 and 66.` Shatt 66 bears `in the easing.;` 38 and is parallel to the axis ot the spindle. A spur pinion 7l) at the end oit sha'lit 66 meshes with a spur `rear 7l. l:eyed at tothe housing.; member 56 axially thereot (Figs. 8 and l0). Spur gear 7l serves as the bracket mounting member 'lor the worin screw 58 which 'is carried thereby about the spindle as the spur rear rotates. A riucj guard 72 is placed over these rotatingl parts.

The planetary motion o' the grinding: spindle continually displaces the spindle driving; pulley 4:7. Since the latter .is belt driven7 suitable means is `provided. for compensating for the changes in driving` distance as traveled by the belt. This :is accomplished by the provision o'lf a movable idler pulley which keeps the belt always Yunder the same tension and thereby prevents elaeli therein as the planetary motion ol the driviiui` spimlle taires place. The motion of the pulley is controlled by the niiet-ion of the spimlle. ',ihe wide drive n pulley 2l (Figs. l and 5)) carries a belt 73 Ato the spindle pulley 4:7, three idlers 7st-, 75 and 7 6 being interposed. ldlers 7stand 75 are fixed and idler 76 movable. The latter is carried by an arm 77 pivoted to the base, in the present instance at the axial center of pulley 75. Pulleys and 7 6 are arranged so that the belt to and from the grinding pulley 41:7 is substzmtially parallel to itselll in both parts. A movable link 7 6 pivot-ally supported at both ends, one end being pivoted at 79 which is the lon e'itudin al center ol arm 77 between the pulleys 75 and 76 and the other being pivoted about the anis of the grinding lot) lll)

spindle. The vhorizontal component of the planetary motion of the spindle is thus transmitted through link 78 to oscillate arm 77, moving pulley 76 substantially twice the horizontal displacement of the spindle. This doubling of the motion takes care of the additive slack in both sides of the belt 73. The idler pulley carries externally thereof a smaller pulley 80 integral therewith which is connected by the belt 64 to the pulley 08 which effects the planetary motion` of the spindle as above described. In the arm 78 a clamping screw 81 is provided to bind the pivot-ally related arm 78 and the spindle rigidly together, thus to prevent motion of the planetary mechanism when not desired, this being an effective locking device.

Grinding wheel carriage.

While the grinding wheel has the rotary planetary motion above described., it is important in some respects that it have also an axial oscillatory motion to present uneven wear of the wheel surface. Means is provided for this purpose which can be put into and out of operation desired. rllhe base 12 carries on its insidea feed screw 85 (Fig. bearing in the base at 86 and at 87, the feed screw being slidable axially in said. bearings. @ne end of the feed screw has two separated flange plates 88 and 89. The carriage 84 has al downward rprojecting portion 90 which carries a nut 91 engaging with said feed screw. Thus', motion of the feed screw rotatably or axially will effect motion of the carriage 84 on its ways 35. Independent means are provided to secure these two motions of the screw. The flanges 88 and 89 provide means to hold the feed screw in the desired axial position. A. bracket 92 on the face of base 1 2 (Figs. 1 and G) supports at pivot 93 a bell crank having a vertical arm 94 and a horizontal arm 95. Arm 94 is bifurcated and has two opposing` pins 96 and 97 which fit between flanges 88 and 89 to hold or to move the feed screw axially accord.- ing to the position of the bell crank. TVhcn the bell crank is stationary the feed screw is stationary. The horizontal arm is arranged to be oscillated to effect a continuous oscillation of the grinding carriage. Suitable means is provided for producing the oscillation from the main shaft. As hei-einbe- -fore stated, bevel gear 27 on countersh aft 22 effects the oscillatory motion. Bevel gear 27 (Fig. is provided with a clutch device engaging it with shaft 227 said clutch being generally indicated at 98. A drawbar 99 to operate the clutch is shown passing through the base 12 to the front face thereof where a handle 100 is provided thereon.4 AV side casin g 101 on the base 12 carries a shaft 102 (Fig. 6) with a bevel gear 108 in mesh with a gear 27 and a worm pinion 104 which is in mesh with a worm wheel 105 on shaft 100 located transversely to the base 12. An eccentric '10Gu on said shaft- 106 lies in the bifurcated end 107 of bell crank arm 95 whereby to effect the reciprocation.

rlhe carriage 34 may be placed anywhere on its ways by suitable means for hand adjustment of its position. l/Vith clutch 98 -thrown out of power connection, the feed Grinding wheel carre/ge feed.

Automatic reciprocal travel is also provided for the grinding wheel carriage 34 and to this end a gear casing 112 is placed on the base 12 for suitable mechanism to effect this motion (Figs. 3, 6 and 7 The mechanisin employed is associated with the feed screw above described and is adapted to rotate said screw to veffect the feed through the nut 91 engaging said screw. Because of the oscillatory motion which may be imparted to the feed screw 85 by the arm 94, the feed screw is splined into the mechanism in the feed box 112 by the key indicated at 113 (Fig. 6). The parts of the mechanism di rectly in splined relation with the shaft constitute the clutch 114 and a bevel gear `115 (Figs. 3 and 6). vThe bevel gear is rotatably fixed in upright member` 116 which provides a bearing therefor within the boX 112. The clutch 114 includes a movable element 117 having an annular' groove 118 therein. A clutch operating means is provided at the top of the box in the form of a radial handle 119 on a shaft 120 which terminates over the groove 118. A. pin 121 eccentrically located in the end of shaft extends into the groove 118 so that turningl of the handle 119 controls the motion of the clutch member 117 into and out of operative position. Because of the desired clutch action onlythe movable clutch n'iei'nber 117 is splincd with the feed screw shaft 85, the remaining elements of clutrh 114 and the gear 115 being freely rotatable and slidable over said shaft which may thus oscillate with or without rotation.

Rotating and reversing mechanism for bevel gear 115 is provided as shown in Figs. il, 6 and 7. The belt 83 from pulley 32 of Fig. 3 runs over a pulley 122 'on a stub shaft 123 journaled in box 112 at one side thereof. With inthe box a spur pinion 124 meshes with a spur gear 125. A. shaft 126 in the box is arranged across the end of the feed screw 85. The shaft-.126 carries the spur gear .fixed thereon and also two loosely mounted bevel gears 127 and 128, each in mesh with opposite sides of the bevel gear 115. Said ice lll

two bevel gears are keyed to sleeves 129 and 130 rotatably carried on the shaft 126, the juxtaposed ends of said sleeves being clutch elements. A third sleeve 131 is splined on the shaft 126 by key 132 and is slidable to the left or the right into contact with either one of the sleeves 129 and 130. The ends of sleeve 131 are likewise clutch elei'nents which can thus be moved so that either gear 127 or 128 turns with the shaft 126. An annular groove 133 is provided in the sleeve for receiving a lugl 134 which moves the sleeve into and out ol; position.

Automatic tripping and reversing mechanism is provided between the grinding wheel carriage and the aforesaid mechanism. This is provided as a movable member automatically moved by dogs the positions of which are adjustable to effect a j )redetermined path for the carriage 34. On the side of the base l2, (Figs. 3 and 6) there is supported a rock shaft 135 with one end bearing in the box 112. Adjustable winged dogs 136 and 137 are secured to the rock shaft 135 by clamping screws 138. Each dog has a wing 139 which is substantially 45 angular to the shaft the wings of both dogs being parallel. Carriage 34 carries a pin 146 which travels a path over ther shaft 135 and between the two dogs so as to strike the `wings 139 in its journey. The wings act as cams and rock the shaft clockuf'ise at one end and counter clockwise at the other end at the travel of the pin 146. lVithin the box the end of shaft 135 carries a rigid crank arm 141 (Fig. 7) which is linked to a lever 142 by a connecting link 143. The lever .142 (Figs. 6 and 7) is pivotally supported at 144- on top of the boar 112, and is provided with a handle 144 for manual operation of the lever. Connecting means from lever 142 to the lug 134 is provided as follows: A liXed shaft 145 parallel with shaft 126 has a U- shaped slide 146 thereon, the base of which ari-ies the lug 134 for motion horizontally to move the clutch sleeve 131. A grooved collar 147 is also slidable on the shaft 145 and is positioned between the legs of the U-slide and maintained. centrally therebetween by two similar springs 148, one on each side of the collar between it and the adjacent legs of the U-slide 146. The end of the lever 142 is biturcated and carries pins 148a (Fig. 6) which lie in the groove of collar 147 to move it. Freely pivoted dogs 149 and 150 moved by gravity lie on the tops of the U-legs, each dog being provided with a shoulder 151 which catches the end of the U-leg as it slides away from the dog and prevents a return thereof toward that end of the shaft 145. The dogs 149 and 150 extend toward the lever 142 which is provided on each side with cam projections 152 and 153 positioned to raise each dog as the lever 142 moves toward it, thereby to release the slide from engagement with the shoulder 151. As the lever 142 is moved toward the right in Fig. 7 the right hand spring 148 will be compressed ltending to move the slide to the right. Vhen the slide moves, dog will drop and its shoulder 151 will prevent the return of the slide. 1f lever 142 is now moved toward the left, which will be accomplished by the rock shaft 135 or manually through handle 144, the left hand spring 148 will be compressed and the slide will not-move because of its engagement with the shoulder 151. At the eXtreme motion of lever 142 the cam `153 thereon will raise the dog 150 and the spring will thereupon cause the slide to move to the left, after which dog 149 will drop to lock it in place. Each such shift of the U-slide 146 carries the clutch sleeve 131 to engage either of bevel gears 127 and 128 and thus accomplishes a reversal of the feed screw 85.

Work table and carrier.

The work end of the machine heretofore alluded to comprises a work table or carriage 16() (Fig. 5) movable on ways 161 on the base section 10. An upright member 162 is removably carried on the table, being bolted thereto at one of several T-slots 163 formed in the tables top surface. Vertical parallel ways 164 are provided on said upright niember 162 upon wh ich a work carrier 165 is slidable by means now to be described. T-slots 165 are provided in the face of the work carrier. The base 11 projecting above the remainder of the machine into a tall column as above described, has a vertical way 166 (Fig. 2) thereon upon which a slide 167 is movably supported. The slide has a bracket 168 on the rear side thereof which is threaded as a nut to engage a rotatable feed screw 169 mounted on the column. The feed screw carries at its lower end a bevel gear 170 (Fig. 4) meshing with a bevel pinion 171 carried by a hand wheel 172. By this wheel the slide may be raised and lowered through rotation of the feed screw. A gage bar 173 and a pointer 174 on a bracket 168 indicate the distance over which motion is made in adjusting the position ofthe slide on the column. The slide 167 carries a pivotal projection or block 175 thereon which carries a radius bar 176 passing therethrough in clamped relationship. A clamp 177 is provided for tightening the radius bar 176 in rigid non-slipping relationship in the pivotally projecting block 175. The radius bar is used to suspend the work carrier 165, a removable lug 178 beineprovided on the top of the carrier for attachment of the bar. A pivotal bearing 179 (Fig. 5) for a pin 180 on the link 176 is provided. By this construction horizontal motion of Vthe carriage 160 causes vertical motion of the suspended work carrier 165 whereby an arc-r uate path results, the radius depending upon the distance between the pivotal points and 179.

Work table feed.

Horizontal travel of the work table 160 is secured by suitable automatic reciprocating mechanism. This is substantially like that. disclosed for the grinding wheel car- 'riage.. A gear box 181 on the base 10 contains the automatic mechanism shown in de tail inF 1g. 4.k The principal features of tue .mechanism duplicate that-already described i gear shaft 182 (Fig. 4). Through t-he box mechanism, generally designated 183, the power is transmitted to shaft 184 (Fig.V 5) which carries the large bevel gear 185 of said mechanism. Between the carriage 160 and the shaft 184 a speed reduction mechanisnrand a clutch means is suitably arranged. Shaft 184 carries a spur pinion 186 in mesh with spur gear 187 carried on a sleeve 188 rotatable onshaft V189. The end of sleeve 188 has clutch teeth `which engage with clutch teeth on a collar 190 slidably splined onto shaft189. A groove 191 in the collar providesmeans for an operating member to move the clutch into and out of engaging position. This means is illustrated in Figs. 8 and 4. A vertical shaft 192 within the base 10 carries an-` arm 193 adapted to move the clutch collar 190 and an, operating handle 194 which is located outside of the base 10, passes through a hole 195 provided in the base. Both arms being relatively long, lit is an easy matter for the operator to control the carriage motion by moving in or out the han- .dle'19 4. Zhen the clutch is in, power is transmitted from gear 187 tov shaft 189. A spur pinion 196 on shaft 189 meshes with y gear197 on a stub shaft 198 and a rack bar 199 carried by the carriage 160 on the under i side thereof meshes with rgear 197. Thus,

the carriage may moved on its bed.

Reversing is accomplished by dogs carried on.` the carriage. A 'lever 200 (correspond ing to lever 142 on gear casing 112) is pivotediV to an upright bracket 201 on the gear casing 181. The manually operated handle 202 of said. lever carries a pin 208 which is struck by dogs 204 and 205 adjustably fixed inf a T-slot 206 on the under side of carriage 160. The tripping of lever 200 in one or the other direction reverses the gear for the carriage inthe manner above described for the grinder mechanism.

In addition to the automatic travel, a hand drive `is provided by the provision of a shaft 207l (Figs. 31 and 4) having rigid therewith the hand wheel 208 and a spur pinion 209 in mesh with an intermediate gear 210 on shaft 211, this ear in turn being in mesh with the gear 197 which moves the carriage.

does not ensure against motion between the o carriage and the bed since turning of hand wheel 208 may trip the lever. Therefore I provide an auxiliary device which may be so clamped with relation to the bed and the carriage that motion cannot result. Such a device is shown in Figs. 12 and 13 (Sheet 4). It is arranged to be clamped to the under side of the carriage by bolts' 212 the heads of which may lie in T-slot 20G. The device comprises a base portion 213 the ends of which have open slots 214 thereinto adapted to receive the shanks of bolts 212. A forked portion 215 extends downwardly from the base and is adapted to fit around shaft 207 of the hand wheel 208. Clamping screws 216 are arranged in the forked portion so as to be screwed onto the shaft 207, thus preventing any play between the' device and the shaft, as well as preventing turning of the hand wheel 208. By this device an assured stationary relation between the carriage 100 and its bed is thus attained. Tn order to permit re ciprocation, this device must be removed from the machine.

In the automatic reciprocation of the carriage 160 there is bound to be some lost motion at the end ofeach travel because of the numerous gears entrained from the power` feeding and reversingmechanism. )Vhen the work carrier 1G5is suspended from the radius bar 176, its weight say in the position indicated in dotted lines of Fig. 1 will tend to move the carriage 160 toward the center. This motion will take place at the end of the travel soonA asthe power is disconnected, because of the lost motion in the gears. To preventA this I provide means which hold the parts at the eXtreme position until thelost motion in the gears hasbeen taken up by the reversal of the gears. The power drive takes up the lost motion and then power moves the table against the force of the holding means. Thus there may be produced auniform travel `in each direction with a short period of rest at the extreme end ofthe travel while lost mo` tion is being taken up. This is accomplished by a friction device bestshown in Figs. 4 and 5. The carriage 160 has a rack bar 217 on its rear side preferably attached to the upright bracket 162. On the column 11 a drum 218 carries an axial shaft 219'with a spur gear 220 at its end meshing with the rack. A friction flange or plate 221 on the shaft 219 bears against the end of the drum 218. Variable pressure produced between the friction surn faces by the provision of a spring 222 and a nut 223 on the other end of the shaft 219 on the opposite side of the drum.

llt)

`in any well known inannei.

Operation.

For operating the machine a variety of: fixtures inay be supplied `for the varied work required oil? it. lin Fi 4 and 5 a fixture 225 is slioivn for clamping a piece of work 226 which in the present instance a link to be radially ground. The fixture is bolted into the T-slots 16:3"L in the vertical work carrier. Other suitable fixtures inay be snbstitiiited either on the vertical or on the horizontal table as required. At the grinding wheel end. the spindle head 53 niay be renioved and rerplaca-id by one of another character tor any special purpose.

Tn grinding the piece of work 226 it is held in the fixture 225 by the bolts 227 passing through lugs 22S on the fixture. The grind iii wheel indicated by the circle t6 is placed iii a statioiia ry position within the cast opening 229 of the link 226. Vitli the work held so that the radius bar occupies its lowerinost or gravity position, the position of the wheel determines the highest point in the are to be ground. As the horizontal table 160 nieves to either side ot this position, the vertical table is carried upwardly by the swinging oit the radius bar 176, this being indicated iii Figure 1 by dotted lines. Such swinging causes the wheel to grind an arc which upwardly convex. In the position shown in l the wheel will grind upper arc 230 as the work iiioves bodily in an arcuate path, always reiiiaining parallel to its fornier positions. lt follows 'troni the character of the linkage that in any position of the wheel an arc ot the saine degree and oit the saine curvature will be ground irrespective `of the position of the wheel with regard to the pivotal center ol the radius bar so long as the distance between the two pivot points of the bar reniain unchanged. Thus` when the wheel etG (Fig. is two inches to the right ot the position indi cated, the are 23() produced at that point would have the saine radius of curvature at the center; and if the Wheel were lowered two inches it would grind a concave arc tivo inches lower than arc 230 which would be an exact dnpl icatc oi the arc 230 in distinction 'frein being concentric therewith.

lith reference to the arc 23() above described, it should be obseri ed that the saine is ground concave by the upper side oit the .points rciiiains unchanged.

grinding wheel e6. lWhen the Work carrier is centrally positioned, with the radius bar 176 in its gravity position, the top ol" the wheel LG niakes contact with the curve 230, the point of contact on the wheel lying `in a vertical. radius oi? the wheel. This illustrated diagraniinatically by Fig. tl (Sheet 7). As the parts inove relatively in an arcuate path, say to position 4h iei: the whecl, the point oit contact nieves to a radius which is angular to the vertical, the singularity oi the radius being equal to the nun'iber oit degrees iiioved by the work. r'tccor-dingly, iff the work nieves 900, say to position leb :tor lthe wheel, the point oi" contact on the wheel would be Qd@ troni the vertical or on a horizontal radins ol 'the wheel. Thus, it will be seen that thc curve which is ground is dependent upon the radius fr et the wheel as well as upon tiie radius R through which the work nieves. The concave arc 230 is then dcterniiiied by the sinn ot the radii'is ariii i7@ and the radius of the wheel, or it R plus r.

lt the wheel is iioiv set so as to grind a convex sui-tace, as, tor example, the arc` indicated by the dotted line 2231, a siiiiilar condi-- tion arises but the radins ot the wheel is 'subtracted 'troni the clliective radius of liar 176. 'lliis is due to the fact that in the initial grav" position the wheel niakes contact with the work at the lower side on a 'vertical radius. As the radius bar swings, the point ot contact ol" the wheel with the work nieves to a radius, the aiigi'ilarity et which from the vertical. is equal to the a rc through which the work. has nioved. For eiiaiiiple, if the work nieves through an arc et 90D iti-oni gravity position it is obvious that the wheel will .iiiakc contact with the work on a radins which is horizontal. The arc 231 defined by the point et Contact et the wheel with the work will then be inside et the are oli radius R (through which the work nieves) by a distance equal tothe radius r ol the wheel. Conselpiently, when a convex arc .is ground the curvature tliercojt is determined by suliitracting the radius oi" the wheel 'troni the length o'lf the radius bar 176, or it lli-sr.

Thus it is obvious that only the elliective length o lf the radius bar 176 between its pi vol s plus or niinus the radius oit the wheel 4.0 dcteriiiines the radius o the are ground. lit is also clear that both the position oit the wheel with. respectto the pivot ol the radius bar, and the position olE lthe pivotal center of the bar on the upwardly extending coluiiin, have no bearing on the degree el curvature so longas the distance between the two pivot ,Y To grind any convex are as arc 232 so as to be concentric with the concave arc 23() it will lie necessary to slierten the radius ariii an ai'nount equal to the di fiereiice s in radii ot the two arcs less the dianieter nl ot the wheel 4G. This is done by loosening the claii'ip 177 and sliding llt) lill) the bar 176 through the block 175 thereby to slierten the radins arm. After tightening the clamp the vertical. slide 167 may be positioned on the column without inlany way afi'ecting the degree ot curvature. In grinding the arcs as illustrated feeding` action may be obtained either through the hand wheel 172 to translate the path oft the work vertically, or by adjustment of the wheel el to move the grinding wheel vertically.

In the operation ot the radius grinding parts as above described, it will be observed that the special character of the motion of the work permits setting` ol the grinding spindle 'i independently of the position of the radius arm, and that i'notion of the horizontal work table is essential to radius grinding. These two features naturally constitute the horizontal carriage ot the grinding spindle and the horizontal work table as elements useful for general grinding practice as in a universal grinding machine. ln such use work may be held on the vertical carrier er the horizontal. table to be surfaced by the wheel or otherwise ground, making use ol the automatic reciprocal travels or both the horizontal work table and the grinding spindle carriage as well as the vertical. adjustment el the grinding wheel on its carriage.

To add to the universality et the machine the planetary motion may be employed by adjusting the screw G2 to produce the desired eccentricity ot the spindle and by connecting the power to pulley G3 to eiliect rotation ot the spindle carrying sleeve 5G. By this arrangement holes may be ground in the usual well known manner. Also, when desired, the work table can be made motionless by applying the clamping device above described and illustated in Figs. 12 and 18 ttor that purpose.

At any time the radius bar may be disconnected and the vertical table 165 may then be made tast to the member 162 on the horizontal table by suitable means tor supporting the work more conveniently in access to the wheel.

In the above description of the machine it is obvious that the particular construction described produces, as regards radius grinding, a relative motion between the work carrier and the grinding wheelin a path predetermined by the relationship existing between the relative motion ot the wheel and the work horizontally, or at right angles to the axis ot the wheel, and the relative motion vertically, or at right angles hot-h to the axis of the wheel and to the lirst motion. ln the present instance the second motion is harmonically related to the lirst motion when the latter is uniform and it is also dependent upon said motion. It will be understood, however, that constructions other than 'the disclosed one may produce a similar or the same result. However, I have preferred to use the described constructionpfor, by reference to the foregoing, it will be seen that have provided a grinding machine which is particularly adapted for radius grinding by the use in common ot 'features which are-of i such a structure that they are also the principal4 features of a universal grinding machine. Since, other embodiments of the principlcs herein set forth are possible by the application oit well known methods of design and oi mechanical. skill, the invention is not to be considered as limited to the machine herein disclosed and described, but is to be considered as broadly as expressed in the terms o'l the appended claims.

l claim as my invention:

1. A grinding machine comprising, in combination, a support, a work table, automatic means to move said Work table horizontally, a work 'arrier vertically slidable on said Work table, suspension means from said support to said carrier, pivoted on said support and tending to hang vertically therefrom, the horizontal motion of said tableswinging said carrier through an are about Ythe pivotof said suspension means, and means between said supc port and said table to hold said table in any pesititm against the tendency oty gravity to move said carrier to its lowermostposition on said arc.

2. A grinding machine comprising, in combina on, a support, a horizontal movable table thereon, a work carrier movable vertically on said table, means to suspend said carrier trom said support, the operative relation of said means, carrier and table being such that the etliect oit gravity upon the carrier might tend to move the table, reversible power means to move said table, rack teeth on said table, a pinion engaging said teeth and bearing in the support, and friction means acting to prevent rotation of said pinion and tending to hold the table' against motion.

53. A link grinder comprising, in combination, a base having spaced parallel ways thereon, a table reciprocable horizontally upon said ways, a vertical guideway on said table, a, work carrier slidable vertically on said guideway, a grinding head adjustably mounted on one side ot said table, a column rigid with said base uprisingtheretrom on the other side ot said table, and' a. radius bar pivotally supported on said column and connected to said work carrier. y

1l. A grinding machine comprising, in combination, a bed having horizontally spaced parallel ways thereon, a table slidable longitudinally upon said ways, a grinding head -adjustahly mounted on said base to one side ol said table, a column uprising Yfrom said bed on the opposite side of the table, a bracket having a 'vertical tace mounted on said table, av work carriage slidable on said bracket perpendicularly to said table, and a single radius bar pivotally supported at one end on said lll) column and connected at its other end to said work carrier.

5. A grinder comprising, in combination, a hase having horizontally spaced parallel Ways thereon, a table slidably mounted upon said ways, a fixture on said table having a vertical guideway, a Work carrier slidably mounted on said guideway, a grinding head adjustably mounted on the hase to one side of said table arranged for operating upon Work mounted on said table or Work carrier, a column uprising from said base on the opposite side of said table, and a single radius bar pivotally supported on said column and pivotally connected to said work carrier.

6. A grinding machine comprising, in combination, a bed, a table slidably mounted on said hed and having a horizontal face adapted for mounting Work pieces, a universal grinding head adjustably mounted on said hase to one side of said table, a column extending upwardly :from said bed on the other side of said table, a radius bar pivotally supported at one end on said column, a Work carrier pivotally mounted on the other end of said bar, and means on said table movably therewith and arranged to guide said Work carrier perpendicularly to said table.

7. A machine tool having, in combination, a supporting base, a Work support movable rectilinearly on Said base, a Work Carrier constrained to slide rectilinearly on said support at right angles to said support movement, and a single bar pivotally connected at one end to said carrier and pivotally connected at its other end. to said supporting base whereby to guide said carrier in an arcuate path during movement of the Work support on the base.

In testimony whereof, I have hereunto affixed my signature.

GUSTAF DAVD SUNDSTRAND.

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