US832775A

US832775A - Grinding-machine.

Info

Publication number: US832775A
Application number: US24526005A
Authority: US
Inventors: James Robert Coe
Original assignee: GEORGE H BENJAMIN
Current assignee: GEORGE H BENJAMIN
Priority date: 1905-02-11
Filing date: 1905-02-11
Publication date: 1906-10-09
Anticipated expiration: 1923-10-09

Description

PATENTED OCT. 9, 1906.

J. R. COB. GRINDING MACHINE.

APPLIOATIOR FILED r33. 11, 1905.-

9 SHEETS-SHEET 1.

No. 832,775.. PATENTED OCT. 9, 1906. J. R. GOE.

GRINDING MACHINE.

AIILIOA'JJION' FILED PEIBJI, 1905.

QSHEETS-SHEBT 2.

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fhl ly PATENTED OCT. 9, 1906.

J. R. 00E.

GRINDING MACHINE.

APPLICATION FILED rmml. 1905.

9 SHEETS-SHEET 3 lza 4 54 1012442 Lav/L Qvil'mcmco PATENTED OCT. 9, 1906.

J. R. 00E. GRINDING MACHINE.

m 4 m 5 i 1 m 5 m w 4 m H v M O Q G 0 2 7 9 5 3 A o 0 I JJE O0 v M. :s l l II? 3 \& m E5: rd l 1 u r u M 5 m G M W 6 M I w 0 H F o o T J n W m 6 9 m u m 6 2 4 o 5 m u n Q 2 6 6 M 5 w I 6 O W PATENTED OCT. 9, 1906.

GRINDING MACHINE.

APPLICATION FILED I'EB. 11. 1906.

9 SHEETS-SHEET 6.

FIGB.

PATENTED OCT. 9, 1906.

J. R. COB.

GRINDING MACHINE.

APPLICATION FILED FEB.11. 1905..

9 SHEETS-SHEET '7 v I J r AI 0 K JQ 6 1 7 U v d M PATENTED OCT. 9, 1906.

GRINDING MACHINE.

APPLIGATION IILED mm 9 SHEETS-SHEET 8.

w w m W IEI 9.10.

PATENTED OCT. 9, 1906.

J. R. COB.

GRINDING MACHINE.

APPLICATION FILED FEB.11. 1905.

9 SHEETS-SHEET 9.

I Ht RN U X UNITED STATES PATENT OFFICE.

H. BENJAMIN. TRUSTEE, OF NEW YORK, N. Y.

GRINDING-MACHINE.

Specification of Letters Patent.

rimmed Oct. 9, 190a.

Applioationfilod February 11 1905- Borial In. M5360- To all whom it may concern:

Be it known that I, 'Jaims ROBERT Con, a citizen of the United States, residing at Ansonia, county of New Haven, State of Con necticut, have invented certain new and use ful Improvements in Grinding-Machines, of which the following is a specification.

My invention relates to grinding-machines of a type adapted as a cutting and finishing machine for metals or other materials.

As grinding was originally considered to be a rubbing or wearing-away 0 eration in which both elements were reduce in pro ortion to their hardness, the grinding-mac line was accordingly constructed merel to mechanically present the rubbing-b0 y to the work toproduce a superior quality of finish over that obtainable by the use ofa lathe or laner. Comparatively recent developments have shown, however, that the operation is actually one of cutting, the grinding-wheel being a gang cutter presenting millions of individual cutting-points each acting in a similar manner to a lathe-tool, and when, therefore, each cutting-point in the surface of the wheel is made to do its share of the work the aggregate removal of stock is such as to make the grinding-machine an important factor both in cutting and finishing. The highest efficiency in cylindrical grinding is obtained when the wheels cutting path on the work is a spiral having a pitch equal to' the width of the wheel; but in practice variable conditions in size, shape, nature of materialbeing ground, and qualities of finish desired make it impossible to invariably use a feed equal to the width of wheel, and means must therefore be provided by which an operator can adjust the feed to the immediate conditions obtaining. It is obvious that the unit of feec should be the width of the wheel, and as practice has proved that a single wheel suitable to the material being ground is capable of both roughing and finishing the work, provision is made in the present machine for changes of feed aduated in definite degrees of one wheel Width. As a grinding-wheel running at a fixed surface speed is capable of removing only a definite amount of material in a certain time and as the amount of surface presented to the wheel at one revolution of the Work depends on the diameter of the cut it is necessary to provide means for changing the speed of the work to suit its diameter, the depth of wheel cut and feed of work constant. It will be readily understood that these adjustments in speed and feedto meet change 111 diameter of work, nature of material, and depth of work are of frequent occurrence, and it becomes of vital importance that the loss of'the operators time necessary for the same should be reduced to a minimum. With this object in view the machine embodying my invention is so designed that every adjustment is clearly defined and conveniently within reach of the operator without requiring him to leave his position at the center of the machine.

In modern grinding-machines the institution of various adjustments has led to the use of extension counter-shafting which makes the handling of heavy work very difficult, preventing, as it does, the use of mechanical lifting and overhead carrying devices. To overcome this ob'ection, the present machine is made entireiy self-contained in its drivethat is to say, it receives power at a definite point either from belt or motor and distributes it internally to the various points of application.

In the modern application of grinding to the manufacture of all cylindrical machine parts it very often becomes necessary to run into a shoulder, thus necessitating providing, first, micrometer means for determining exactly the point of feed-stop; second, a delayed reversal until the work makes at least one complete revolution in order to revent leaving a portion of the surface u ished, and, third, means for insuring against slippage in the operating parts of the reverse mechanism. To meet these conditions, I employ a timed mechanism actuated directly by the driving-shaft operating the headstock instead of through clamp dogs attached to the table, as is the case in other machines, the action of placing the mechanism in operation being through the dogs striking screws having micrometer adjustments and locking-nuts. The reverse mechanism is also arranged to operate the cross-feed device for determining or adjusting the cut of the wheel while the table is standing still, thus eliminating the tapering off of the ends of the work by the feeding in of the wheel before the end of the stroke, as is the case inall existing machines in which the cross-feed mechanism is operated by the table-dogs. The crossfeed device is so arran ed that the amount of feed is governed and graduated index, the a obvious.

Modern grinding-machines are ordinar ly provided wlth means for operating the tabletraverse by hand as well as power, and as the two have never been made distinct in their action the hand-wheel is constantly revolving when the table is in operation, thus forming a menace to the safety of the operator. To avoid this, the present machine is so designed that the 0 eration of a clutch automatically preclu es the operation of the hand-wheel when the power-feed is in action, and vice versa.

Practice in grinding today includes the use of a large amount of soda-water, which actsto destroy the machine-oil used to lubricate the sliding bearings unless they are protected or covered. Protecting means of various kinds have been employed in existing machines, some using an extended cover of cast-iron attached to the ends of the table, which adds to the necessary floor-room required by the ma chine. Others use sheet-iron strips attached to the bed throughout its 1e th and extending inwardly, requiring the ta le to be undercut to clear these guards, and thereby greatly weakened, or a canvas strip similar to a win dow-curtain, which quickly wears out, owing to its contact with the oil. For this purpose I have provided a flexible metal strip extending through holes in the table and so arranged as to overcome all the aforesaid objections.

A very important featurein modern grindvantage of whic is ing is the use of back rests to prevent sag orspring of the work away from the wheel. For work of fairly large diameter only single blocks are used at the back of the work,

while for work of small diameter an extra piece is used carrying blocks to support the work both from behind and from below. In machines now in general use such a sin le block is adjustable vertically and inward y independent screws, the adjustment of either 'of which disarranges theother. 'To overcome this ob'ection, I have provided means for indepen ently adjustin the vertical blocks and the horizontal b ocks in direct lines.

A machine suitable for carrying my inven owever, that I do not limit myself to the same, as various other mechanisms may be employed, operating in substantially the same manner to produce practically the same.

result.

In the drawings, Figure 1 is a front eleva tion of the machine. view. Fig. 3 is a cross-sectional view of the machine, taken on the lines 3 30f Fig. 1, show- (predetermined b ament in the base, as shown at t 2 is a top or plan- 'wheel-sli ing relative position of parts with largest wheel and Work. Fig. 4 is a similar view taken on the line 4 4 of Fig. 1. Fig. 5 is a cross-section taken on the.l1ne.5 5 of Fig. 2.

6 is a horizontal section taken on the line 6 6 of Fig. 1. Fig. 7 is an enlarged cross-sectional view taken on line 7 7 of Fig. 1, showing the work in position. Fig. 8 is an en-- largedfront view of the dri mechanism, shown with parts shown in sectlon. Fig. 9 is an enlarged front view of the driving mechanism, showing a modification of the reverse mechanism. 10 is an enlarged view in the perspective of the end of the machine,

showin one of the oil-pockets and'its contained eedroll employed in the bearings of the wheel-spindle. Fig. 13 is an enlarged detail front view of the reverse mechanism. Fig. 14 is a similar viewof the same in an adjusted position. Fig. 15 is a sectional view on the line 15 15 of 14; Fig. 16 is a sectional view of the reverse mechanism, taken on the line 16 16 ofFig. 14.

Referring now to the drawings, the base or bed 1 is provided, as shown in Figs. 1 and 7, with ways 2, extending laterally throughout its length, forming sliding surfaces for the table 3, such ways having at intervals oilpockets 4, in which oil-rolls 5 of familiar construction are so arranged as to operate ICO against and supply oil to the bottom of the mediately behind the ways and extending.

Oil-pockets 6 to receive the overflow throughout the length of the base is a trough 8, Fig. 4, adapted to receive the water ,used in operation and convey it back to the settling-tank 9, which is formed 1) a comparthe left of the wheel in 2 This settling-tank 9, as shown in Figs. 2 and 3, is separated from the pump-tank 10 immediately behind it by a partition 1 1, over whichthe water flows into the pump-tank after depositing any grit it may hold in the settling-tank. Underneath thesettling and pump tanks, Figs. 5 and 6, is a space 12, left clear for a cone-belt, and to the right is shown a compartment 13 for the wheel-driving mechanism. The compartment 13, as shown in Figs. 2, 4, and 5, is surmounted by the wheel slide-base 14, a cast ing having ways 15 extending throughout its length at right angles to the direction of the table-'wa s on the base and on which the d e is carried back and forth by means of the screw 16, carried in bearings 17,

extendin downward from the bottom of the screw is operated and engaging with the ways on the wheel slide base. A half-nut 23, extending downward from the bottom of the wheel-slide 21, Fig. 4, engages with the screw 16. At the front of the wheel-slide 21 are rovided bearings 24 for the wheel-spin e 25. Thesev bearings, Figs. 2 and 4, are bronze-lined and are rovided with caps 26. fitted at an angle of fbrty-five degrees, thus presenting a solid surface to the back thrust of the wheel and the downward thrust caused by the weight of the wheel-spindle and belt-pulley. Oil is supplied to these bearings by means of oil-rolls 27, having a roughened surface carried on the swinging frames 28 in pockets 29 in the wheel-slide and extending upward through slots 30 in the bronze liners 31 to contact with the wheel-spindle 25, which contact is insured b means of spring acting against the lower sid e of the swinging frames, as shown Figs. 4 and 12. The wheelspindle 25, operating in the bearing 24 in the wheel-slide 21, is a heavy steel spindle carr -ng the wheel 32 on one end, having a t rust-bearing 33", Fig. 2, on the other end and a drive-pulley 34 located between the bearings.

The wheel is secured to the spindle in the usual manner and, as shown in Fig. 3, revolves in a heavy ward and back on ways 36, Fig. 2, provided at the side of the Wheel-slideto compensate for wearing down of the wheel. This casing serves the double purpose of protecting the operator from injury in case of wheel accident and of confining the water of operation from misting while being led back to the settling-tank.

As shown in Fig. 4, the wheel-spindle is driven from a jack-shaft 37 in the compartment 13 in the base by a belt 38 traveling over idler-pulleys 39, which are carried in a

frame

40,1 ig. 2, arranged to slide back and forward in ways 41, provided on the wheelslide, this idler-frame being drawn toward the back of the wheel-slide by means of the heavy spring 42, Fig. 2, thus putting the necessary tension on the belt. Hinged on the wheel-slide bearing-ca s 26 is shown a cover 43, Figs. 2 and 4, w ich extends over the belt-bulley 34 and protects the same from water. Hinged to the first cover 43 is a second cover 44, which extends down in front of the wheel-slideways 22, the operation of which is clearly shown in its extreme positions in Figs. 4 and 7. The wheel jackshaft 37 revolves in bearings 45, Fig. 6, se-

cured to the machine-bed, and is driven by casing 35,

adjustable forgears

46, 47, 48, 49, 50, and 51 from 'the main shaft 52.

Three changes of gear speeds are provided to compensate for the wearing down of the wheel, the object being to keep the surface s eed of the wheel approximately uniform.

his main shaft receives power for the entire machine from a belt running over tight and loose pulleys 53 5 4, as shown at the extreme right of Figs. 2 and 6. A ulley 55 at the opposite end of the main sha t, Fig. 5, drives, by means ofa belt 56, running over guidepulleys 57, a pump 58 of the well-known vertical centrifugal type commonly used on work of this character and which is carried on the perforated cover 59 to the pump-tank 10 in the bed and supplies water to the point of contact through hose 60 and pipe 61. (Shown in Figs. 2 and 3.) The main shaft 52 also carries a drumulley 62, Fig. 6, which drives the cone-pu ey 63 on the front of the machine, by means of an endless belt 64, running over take-up idlers 65, Fig. 3, swinging on a stud 66, extending from the bed and o erated by a spring 67. The conepulley 63 as five steps and provided with a tapered portion 63, Fig. 6, between the steps to permit the shifting means of a shipper 68, (shown in Fig. 7,)

which is arranged to slide along a track or bar 69, secured to the drive-plate 70, fastened to the front of the machine and carrying the entire drive mechanism.

The cone-pulley 63 revolves the main drive-shaft 71 through a cone friction member 7 2 ,(shown clearly in Fig. 8,) the object of which is to provide a safety-point in case of accident. Immediately to the right of the cone-pulley on the main drive-shaft 71 are shown two loose clutch-pulleys 73 74, Fig. 8, each of which carries a belt 75, which, running over swinging idlers 76, Fig. 7, drive the drum 77, carried underneath the sliding table in bearings secured to the sliding table, from which in turn power is transmitted to the head-stocks, as hereinafter described. These two loose pulleys 73 74 on the main driveshaft 71 have a diainetrical ratio of one and two and are arranged so that either one can be driven by the shaft through the sliding jawclutch member 78, operated by means of the lever 79. (Shown clearly by F ig. 9.)

It will be clearly seen that the arrangement described gives two changes of head-stock speedi,. e., fast and slowfor each of the five speeds imparted by the cone-pulley 63 to the main drive-shaft 71, .or ten head-stock speeds in all, five of which are designed to be used for finishing work, the figures shown on the cover representing the revolutions per minute that the head-stock will make when the belt is in any one of the several positions.

At the extreme right of the main driveshaft 71, as shown in Fig. 8, is located an-. other cone-pulley 80, WhlOh drives a correof the belt by length of the cone-pulleys.

sponding cone-pulley 81 on a jack-shaft 82, immediately above the main drive-shaft. The proximity of these shafts and the necessity of providing a single shipper for the belt approaching both pulleys requires the use of a special drive, which is shown clearly m Fig. 4 as consistin of three idler-

drums

83, 84, and 85, of wi th of face e ual to the he middle idler 84, carrying the tight or pulley side of the belt 86, is carried r1 'dly on a stud 87, extending from the brac et 88. The upper and lower idlers are carried on a swinging frame 89, hinged on a second stud 90, ex-

tending from the bracket and operated by a tension-spring 91. The belt 86 is endless and runs in the direction indicated by the arrows approaching both pulleys through the bat-wing shipper 92, Fig. 4, which is arrangpd to slide on a track or bar 93, secured to t e drive-plate.

As shown in Figs. 14 and 16, the second or jack shaft 82 carries two tight pinions 94 95, which engage with loose clutch-gears 9697 on the worm-shaft 98, one engaging direct, the other through .an intermediate 99, the relative proportions of each pinion to its gear being identical. The worm-shaft 98, as shown in Fig.8, revolves in bearings 100, forming part of a bracket 101, and carries. a

worm 1-02, running in an oil-bath 1 03 and engaging with a bronze worm-wheel 104, which,

as shown in Fig. 7, revolves loose in a web or rim bearing 105 on a hub 106, tight to the. rack-pinion shaft 107. A spur-gear 108 is shown as having a similar bearing 109 on the hub 110 and as engaging with a pinion 111 and hand-wheel 111. Both the wormwheel 104 and the spur-gear 108 have clutchteeth 112 cut on their inner periphery, as shown by Fig. 8, and a sliding key 113, having a bearing in the hub 110 and operated by means of a knob 114, extending to the front, is arranged to engage with either the wormgear 104 or spur-gear 108, so that only one can be coupled to the rack-pinion shaft 107 at'a time. The rack-pinion shaft 107, Fig. 7, carries the rack-pinion 115, en aging with a rack 116, secured to and exten g throughout the length of the sliding table 3, and revolves in bearings117, forming part of the worm-bearing bracket 101. It will be observed that for each of the five separate speeds of the main drive-shaft the jack-shaft and the worm-shaft and the table have five distinct changes of speed by means of the double cones on the main and jack'shafts,

and the-machine is so designed that these five changes of speed represent one,three-fourths, one-half, one-fourth, or one-eighth of a wheelwidth table travel per revolution of the headstock when driven slow speed, enabling the operator to adjust his table to any desired feed for roughing. Moreover, inasmuch as the table change is absolutely independent of the fast and slow head-stock changethe change of head-stock speed from slow to fast for finishing beingin the proportion of one to two-when the fast head-stock speed is being used the table advance per revolution automatically becomes only one-half as eat, thus preventing too fast a table spec and gnvmg the finer or smaller speeds required for 'shmg-namely, one-half, three-ei hths', one-fourth, one-eighth, or one-sixteent of a wheel width-per head-stock revolution. I

The reverse mechanism is shown in two forms, the first and preferable being shown in Figs. 8 and 13 to '16 and the second, a modifi cation, shown in Fig. 9. Both have for their object to provide a delay in reversing of. sufficient time for the head-stock to make at least one complete revolution irrespective of Whatever table-feed ma be in use, and it will be observed that in or er to attain this object the timing of the delay must be'made from the main drive-shaft.

Treating the two methods independently and in consecutive order, the first consists, as shown in Fig. 8, of a tight worm 118 on the main drive-shaft 71 operatin a worm-wheel 119, Fi 16, which revolves oose on a quill 120 an carries with it a ratchet 121. This worm-wheel 119 is so designed that the number of revolutions of the main drive-shaft 71 required to cause one complete revolution of the head-stock shall also cause one-half of a revolution of the worm-wheel. Secured to the quill 120, Fig. 16, which revolves on a stud 122, extending from the drive-plate 70, is a sprocket-wheel 123 at the rear end, and at the front end in consecutive order, as shown in Fig. 15, are, first, a pawl-arm 124, carrying a pawl 125, arranged to engage with the teeth of the ratchet 121 on the wormgear 119 and'held'in such engagementby a spring-plunger 126, unless forcib yheld from such engagement by the interference of a tail 127 on the pawlwith stop-pin 128, carried on slide 129, Fig. 14; second, a reversecam 130, having two steps 131 and 132, as shown, and, third, a stop-cam 133, which is a round disk with a notch 136 in its periphery, as shown. The slide 129, mounted in rollerbearin s 137, Fig. 14, secured to the driveplate, as an upwardly-extending yoke 138, designed to engage with and operate a clutchsleeve 139, sliding on a featherkey in the worm-shaft between the two loose clutch- 7 gears 96 97 and so arranged that it can be in engagement with only one of them at a time. TlllS slide 129 carries two oppositely-placed spring-plungers 140 140, Fig. 15, so arranged as to engage with the reverse-cam 130. Two stop-pins 141 141 on its outer surface are arranged to engage with the stop 'cam, and two stop-pins 128 128 on its inner surfaceengage with the tail of the ratchet-pawl 125. At its extreme upper part the Ishde 129. carries a steel ratchet-tooth 142, Fig. 14, arranged to engage with either of the two (pawls 143 143, carried on studs 144, exten ing from the drive-plate 70. These pawls 143 have arms 145 extending up to and encircling a shipper rod 146 (shown clearly in Fig. 13) and are designed to be moved outwardly by collars 147 on the rod and inwardly by springs 148 on the rod. The rod slides in bearings 149, provided by a bracket 150, and has at its center an arm 151, extending upward and carrying at its upper extremity a hub 152, Fig. 13, into WlllCh two micrometer-screws 153 with graduated heads 154 and lock-nuts 155 are adjustably secured in such position as to normally stand in the path of t 1e table-dogs 156, which are adjustably carried on a rod 157, extending throughout the length of the sliding table. The striker-arm 151 is held in its normal upright position by means of a springplunger 158, Fig. 16, carried on the bearingbracket, and is provided with a handle 159 to permit its operation by hand and also to permit its being revolved out of the path of the table-dogs 156 against the actlon of the spring-plunger 158 when it is found desirable to run by, thus preventing'thc necessity of changing the location of the dogs.

The operation of the reverse mechanism is shown in detail in Figs. 13 and 14 and is as follows: In Fig. 13 the mechanism'is shown just before the reversin action takes-place, and it will be observed that the slide 129 is in its extreme right-hand position, the clutch member 139 being in engagement with the right-hand clutch-gear 97 and held in such engagement by the left-hand locking-pawl relative position of the various parts imme diately after the reversing action has taken lace, and it will be observed that the rightand table-dog 156 has struck the ship errod 146, which in turn has lifted the lefthand locking-pawl 143. The lefthand slide sprin -plunger 140 has at once acted and forced the slide 129 to the left until the ri hthand stop-pin 141 on the front of the side engaged with the stop-cam 133 and sto ped the motion of the slide 129 and the c utch member 139 in a central osition, thus stopping the table-feed. This same left-hand motion of the slide 129 has drawn the interfering pin 128 out of engagement with the ratchet-pawl-125, and the spring has forced the pawl 125 into engagement with the tion of the quill 120 with both the cams 130 133 and the sprocket-wheel 123. This revolution continues until the second step of the reverse-cam 130 strikes the left-hand slide spring-plunger 140 and compresses it until t 1e notch in the stop-cam 133 asses by the right-hand stop-pin 141 on t e slide 129. Then the left-hand sp g-plunger 140 a ain acts and causes a second motion of the side 124 and clutch member 139 to the left, thus causing the reverse in the direction of the table travel. This second movement of the slide, moreover, permits the right-hand locking-pawl 141 to engage the tooth 142 on the top of the slide 129 and at the same time brings the righ t-hand interference-pin 128 on the inside of the slide 129 into the path of the tail 127 on the revolving pawl 125. The revolution continues enough farther to permit the reverse-cam 130 to compress the right-hand slide spring-plun er 140, and the ratchetpawl 125 then pul s itself out of engagement by the tail 127, and the mechanism is again in working order.

The second form of reverse mechanism, as shown in Fig. 9, consists of a worm 118*, loose on the main drive-shaft 71, having clutch-teeth on either end. This worm engages a worm-wheel 119, which revolves loose on a stud 122, extending from the drive-plate 70, and carries with it, first, a reverse-cam 130*, which is a round disk havinga spring-plunger 138 extending out throu h its periphery and a notch 131 in its perip ery directly opposite its plunger 138; second, a stopcam 133, which is a round disk having a pin extending from its periphery, and, third, a sprocket-wheel 123.

Two primary levers 143 are hinged on studs 142, extending from the plate 70, having contact-points 139 at their upper ends, adapted to engage with the stop-cam 133, and also notches 140, arranged to engage with the locking-pawls 141, which are shown as suspended from a bell-crank 149 through bearings 147*.on the drive-plate 7 0. At their lower ends the primary levers 143 are held apart by a heavy compression-spring 146 and are designed to engage with and operate two clutch members 137', sliding on feather- Y keys in the main drive-shaft 71 and arranged to eng c with the clutch-teeth on either end of the oose worm. Two secondary levers 143 also hinged on the same studs as the primary levers 143', have contact-points arranged to engage with the reverse-cam 130" and at their u per ends are secured to a shipper-rod 144", having a yoke 136", designed to engage with and operate the clutch member 137, sliding on the worm-shaft 98, between the loose clutch-gears 96 97. The table-dogs 156 are provided with adjustable micrometer-screws 151, carried on a hinged piece arranged to normally lie in such position as is standing I secondary e to interfere with the striker-arm of the bellcrank 149, but capable of being lifted to a clearing lposition. The mechanism is shown just as t e reversing action is about to take place, and it will be observed that both the primary levers 143 are in a restrained position and held insuch a position by the lockingawls 141. Consequently both clutch memers 137 are out of engagement with the worm 118 on the main drive-shaft 71', and it still. Moreover, the left-hand ver 143 is in the notch in the re-' verse-cam 130and held there by the action of the sprin -plunger 138' against the righthand secon ary lever 143', and the clutch member 137 a is consequently in engagement with the right-hand loose clutch-gear 97, and the table is travelin in the direction shown by the arrow. The eft-hand table-dog 156 is, however, in contact with the strikerarm of the bell-crank 149", and the left-hand locking-pawl 141 is about to release the left hand primary lever 143. As soon as this release occurs the compression-spring 146 will act, forcing the primary lever 143 in toward the center, thus entering the left-hand clutch member 137 into engagement with the clutch-teeth on the left-hand end of the worm 118 and causing rotation of the same. As soon as this rotation commences the reversecam 130 will force the left-hand secondary,

lever 143 out of the notch in its periphery and the upper clutch 137 will assume a central position, thus stopping the table-feed. This delay will continue while the wormwheel 119 and cams continue to revolve until they have made a half-revolution, in which time the head-stockwill have made at strikes the left-hand secondary lever 143", it

- will be compressed until the notch in the reverse-cam passes the contact-point of the right-hand secondary lever 143", when it will immediately act' and force the upper clutch member 137* into a left-hand position, causing the reverse in the table motion. The further rotation of the worm-wheel and cams brings the projecting pin 139- in the periphery of the stop-cam 133 into engagement with the left-hand primary lever 143, thus forcing out the lower left-hand clutch 137 b and stopping furtherrevolution of the worm 118. either case'it will be observed that the sprocket-wheel 123, secured to thecams, makes one-half a revolution every time the motion of the table is reversed, and the said half-revolution takes place while the table is standing still. This sprocket 123 is'arranged, as shown in Figs. 8 and 16, to drive, by means of a chain 158, a second sprocket 159, whose diametrical ratio to the first is as one to two. Hence the second sprocket will make a complete revolution when the reverse occurs. This second sprocket is arranged, as

shown in Figs. 8 and 16, to revolve a crankdisk 160 through a spring-pin 161, capable of being withdrawn when it is not desired to use the automatic cross-feed. The bell-crank 162 carries on one arm a spring-pawl'163, arranged to engage with the teeth of a spur-gear 164, tight on the wheel feed-shaft 20, the design of the machine being such that each tooth in the periphery of the gear represents a wheel advance of one one-thousandth of an inch, as shown clearly in Fig. 8. A shoe 166 is also hinged on the wheel feed-shaft in such a manner as to hold the pawl out of engagement during any desired 'part of its reciprocation, and this shoe, havin a springpin 167, Fig. 9, engaging with numbered holes 168 in the cover 169, enables the operator to adjust the feed to any predetermined number of one one-thousandths required. Engaging with the spur-gear 164 is a pinion 170, carrying a hand-wheel171, the eriphery of which is graduated, thus provi ing suitable means for manually advancing or backing of the wheel. a

The sliding table 3 is provided with ways on its lower surface corresponding to and engaging with the ways on the machinebed, as above described. The table-rack 1 16 (shown in Figs. 7 and 8) is also secured to the lower side of the sliding table and extends through- .outits length, as does the head-stock drum 77, which revolves in self-oiling bearings secured'to the sliding table. On its front edge "is carriedthe rod 157, Fig. 1, along which the table-dogs 156 are adjustable. At either end of the sliding table is a clam ranged to hold down the swivel-ta le 3, the right-hand clamp being provided with a binding-screw and handle 173. (Shown clearly in Fig. 1 Extending throughout the length of the sliding table immediately over each way are provided rectangular holes or chambers, through which are arranged to operate the bed water-guards 174. (Shown in Fig. 10.) Each of these guards consists of two strips 175 of thin flexible sheet metaljo'ined together by means of a spiral spring 176, the whole guard in a normal condition being the same length as the bed. These guards are arranged to operate through the slots 177 in the sliding table, passing under the guiderolls 178, shown at the ends of the table, and are connected together at their extremities by means of a round rod 179. Yoke-pieces 180, providedon the ends of the bed, are adapted to engage with the ends of these rods 179 when the table passes in from the end of the bed, thus causing a stretching of the spring members of the guards. Yokes 181 are also provided on the ends of the sliding table to support the rod when the table passes out away from the end of the bed, as shown clearly by Fig. 10. The swivel-table 3 is arranged to rest on the top of the sliding table, to which it is held at its center by means of a pivot 182, entering both tables, (shown by Fig. 7,) which construction permits of a rotation or swiveling of the swivel-' table 3 about the pivot in a horizontal plane on the sliding table 3, this rotation being governed by means of a screw 183, carried by the swivel-table, engaging with a nut 184, carried by the sliding table, as shown by Figs. 1 and 4. On its upper surface the swivel-table is rovided with ways 185, along which the head-stock 186 and foot-stock 187 are adjustably secured by means of binding-bolts 188, the heads of which engage with a slot 189, provided in the upper side of the swivel-table or this purpose.

Carried in brackets'190 on the ends of the swivel table 3 is a shaft 191, extending throughout the length of the table and located over the front way, as shown in Figs. 3 and 7. This shaft 191, Fig. 3, is revolved by means of a belt 192, driven by-the drum 77,

carried on the lower side of the sliding tablev and running over take-up guide-pulleys 193. carried on a frame 194, attached to the end of the swiveltable. .The shaft 191 has for its object the revolution of the head-stock driveplate by means of a pinion 195, carried by the shaft in such a manner as to be capable of lateral motion with the head-stock, and an intermediate pinion 196, engaging with the first pinion 195 and with a large s ur-gear 197, arranged to revolve about the cad-stock deadcenter 198 and carrying the head-stock driveplate 199, to which are secured the work drive pins or dogs 200. The head and foot stocks are of familiar type common to this class of machinery and need no description. They are both adjustable in and out from the center of the swivel-table, their working position when determined to suit the length of the work being secured by means of bindingbogzs and handles 201, as shown by Figs. 2, 3, an 4.

The back-rests 202 (shown by Figs. 1 and 7) are arranged to be carried on the swiveltable, to which they are secured by means of a swinging clamp 203 and binding-screw 204 and consist of a box 205, having a hinged cover 206, provided with a clamping-screw 207 and having on its front side an adjustingscrew 208, designed to operate against a sin gle wooden or babhitt block 209, which in turn supports the work 210. When the work is of small diameter, it is necessary to support it from below, as well as from the direct thrust of the wheel, toward the front of the machine. For this purpose a special frame 211, known as a universal back-rest, is arranged to be removably carried in the primary box, to which it is secured by dowelpins, as shown, and is also designed to have a support bearing on the swivel-table itself. The frame 211 is provided with a vertical way 212, on which the vertical block 213 is just his wheel-feed to the .greatest knob 215, as shown.

' The operation of themachine described briefl is as follows: The operator selects a wheef the piece of work to be ground and secures the same to the wheel-spindle, having removed the wheel-guard orcasing-cover tu permit access to the same. the head and foot stocks to such a position as will bring the work ap roximately in the center of the machine. an adjusts'the back-rests to properly support the work, using thesingle blocku ports if the work is of large diameter or of comparatively short length in relation to its diameter, or using the universal-back-rest framesif the W0 k is of small diameter. He next adjusts his table-dogs to give the requisite table travel and observes as to whether the swivel-table is pro erly set to grind straight or tapering, as t e case may beg He next adjusts the speed-;

change gearsat the back of the machine to suit the diameter of the wheel he may be He. then adjusts adj ustablebymeans of a screw 2 14 and handsuitable for the nature of material of 7 using and starts the machine in o eration.

With the machine in operation his st duty is to see that the wheel is running true, and 1f not to dress it by means of a diamondtool. He then determines what speed of the head-stock he re ui-res for the particular diameter of the woi k and makes his adjustment for the same. For example, if the work were of as large diameter as the machine could swing he would use the slowest speed possible. His next operation is to bring the wheel up to the work and open the water-valve on the pump-line and so direct the flow as to strike the contact-point between wheel and work. .He will then adractical depth of cut and adjust his tableeed to the greatest practical degree of. the unit, one Wheel width per revolution of the head-stock, and roceed to rough down he work, the spiral cut produced by the wheel upon the work being indicated by dotted .lines in Fig. 11. If a considerable amount of stock is to be removed, he, having determined how many thousandths of an inch can practically be removed at each cut, will set the automatic cross-feed at that point, and he can then devote his entire attention to the mani ulation of the back-rest-adjusting screws, wl fich, of course, have to be continually adjusted as the work decreases in diameter. Having roughed the work down within a small limit of the desired size, his next operation is to throw in the fast speed of headstock, reduce the depth of cut, and adjust the table-feed to such a degree as will give the desired finish, and in event of enough roughing-work having been done to roughen the surface of the wheel before taking the last out he will run his table by and dress the wheel by means of a diamond-tool supported by the foot-stock. 1

I claim 1. A grinding-machine, com rising a ro' tary cutter, supporting means or the work, means for adjusting the cutter andthe work relatively to eachother, means for giving the work rotary and longitudinal feed and graduated means for uniformly arying the speed of rotation of the work. j

2. A grinding-machine, com rising "a rotary cutter, supporting means or the work, means'for adjusting the cutter and the work relatively to each other, means for giving the whereby the longitudinal feed and rotary feed are given a definite changeable relation.

4. A grinding-machine, comprising a ro tary cutter, supporting means for the work, means for adjusting the cutter and the work relatively to each other, means for-giving the Work rotary and longitudinal feed and means whereby the longitudinal feed and rotary teed are given a graduated definite changeable'relation.

5 A. grinding-machine, comprising a rotary cutter, supporting means for the work, meansfor adjusting the cutter and the work relatively to each other, means for giving the work rotary and longitudinal feed and means .whereby the longitudinal feed and rotary.

feed are given a definite changeable relation graduated in terms of one wheel width.

6. A grinding-machine, comprising a rotary cutter, supporting means for the work,

means for adjusting the cutter and the work relatively to eachother, means for giving the work rotary and longitudinal feed, means. for automatically reversing the longitudinal feed, and means for automatically stopping the longitudinal feed on each reversal for a time sufficient for the work to rotate through a definite number of degrees.

7. A grinding-machine, comprising a rotary cutter, supporting means for the work, gearing for driving the cutter, means for varying the" speed of rotation of the cutter, cross-feed mechanism for advancing the cutter, means for giving the work rotary and longitudinal feed, means for automatically reversing-the longitudinal feed, and means for automatically stopping the longitudinal feed on each reversal for a time suflicient for the work to rotate through a definite number of degrees. I

8. A grinding-machine, com rising .a rotary cutter, supporting means or the work,

relative speeds, longitudinal feed mechanism '.for the Work, means for automatically reversi'ng the feed at predetermined points,

and means for retarding the action of the re-' versing mechanism to sto thefeed and ermit the workto rotate t ougha comp ete j revolution.

9. A grinding-machine, com rising a irotary cutter, supporting means or'the work,

means for rota-ting the cutter and'work at relative speeds, longitudinal feed mechanism for the work, means for automatically reversing the. feed at predetermined pornts, said reversing means consisting of requisite clutches, locking-dogs for the movable clutchmembers, and adjustable trips for the locking-dogs, together with means for automatically disengaging the clutches to st the feed and permit the workto rotate t --ough a gomdplete revolution on each reversal ofthe 10. A grinding-machine. comprising a retary cutter, supporting means for the work,

means for rotating :the cutter and work at relative speeds, longitudinal feed mechanism for the work, means for automatically reversing the feed at predetermined points, said reversing means consisting of requisite clutches,.locking-dogs for the movable clutch members, and adjustable trips for the locking-dogs, together with means operating to disengage the clutches, and timed cams acting through said last-mentioned means to control the rengagement of the clutches.

11. A grinding-machine, comprising a rotary cutter, a Work-supporting table, means for rotating the cutter and work at relative speeds, longitudinal feed mechanism for the table, means for automatically reversing the feed at predetermined points, said reversing means consistingof re uisite clutches, locking-dogs for the mova le clutch members, and adjustable tri s carried by the table cooperating with' t e locking-dogs, together with a clutch-shifter spring actuated to disengage the clutches, and timed cams controlling the adjustment of the shifter.

12. A grinding-machine, comprising a rotary cutter, a work-supporting table, means .for rotating the cutter and work at relative speeds, continuous-feed mechanism cooperating with the table, means for reversing the table-feed at predetermined points, means for advancing t e cutter to the work by hand,

and means for advancing the cutter to the power independent of the tableby power, independent of the table-feed, and

means to predetermine the amount of such advance.

14. A grinding-machine, comprising a r0- tary cutter, a work-supporting table, means for rotating the cutter and work at relative speeds, continuous-feed mechanism cooperating with the table, means for reversing the table-feed at predetermined points, means for advancin the cutter to the work by hand,

means for a vancing the cutter to the work by power, independent of the table-feed, and graduated means to predetermine the amount of such advance.

15. A grinding-machine, comprising a rotary cutter, a work-supporting table, means for rotating the cutter and work at relative speeds, continuous-feed mechanism cooper- .ating with the table, means for reversing the table-feed at predetermined points, means for automatically stopping the table-feed on each reversal for a time suflicient for the work to rotate through at least a complete revolution, means for advancing the cutter to the work by hand, means for advancing the cutter to the work by power while the table-feed is stopped during reversal.

16. A grinding-machine, comprising a ro tary cutter, a work-supporting table, means for rotating the cutter and work at relative speeds, continuous-feed mechanism cooperto redetermine and govern the amount of suc advance.

17. A grinding-machine, comprising a rotary cutter, a table movable in a direction parallel to the axis of the cutter, supporting means on the table for the work, changeablespeed gearing connected to rotate the work, longitudinal-feed mechanism for the table, means for automatically reversin the tablefeed and means for automatica lystopping the table-feed on each reversal for a time sufficient for the work to rotate through a complete revolution.

18. A grinding-machine, comprising a rotary cutter, a table movable in a direction parallel to the axis on the cutter, supportin means on the table for the work, cross-fee mechanism for the cutter, longitudinal-feed mechanism for the table, means for rotating the cutter and work at relative s eeds means for changing the speeds, means or automatically reverslng the table-feed and means for stopping the table-feed on each reversal for a time sui'licient for the Work to rotate through a complete revolution.

19. A grinding-machine, comprising a ro tary cutter, a work-supporting table, means 'for rotating the cutter and work, means for giving the table longitudinal feed by hand, means for operating the table-feed by power and means whereby the operation of the hand-feed and power-feed is automatically made independent.

20. A grinding-machine comprising a rotary cutter, a work-su ortin table, supporting means on the ta e for t e work, said supporting means consisting of a frame having bearing portions independently movable thereon in direct lines vertically and horizontally relatively to the work.

21. A grinding-machine, comprising a bed provided with ways, guards covering the ways, a sliding table on the bed and means for providing clearance between the guards and ways for the table in its travel.

22. A grinding-machine, comprising a bed provided with ways, flexible guards covering the wafys, a sliding table on the bed and means or raising and lowering the guards to provide clearance for the tablein its travel.

23. A grinding-machine, comprising a bed provided with ways, flexible strlps serving as uards for the ways, a sliding table upon the bed, said table being provided withopenings above the plane of the ways through which the guards pass and means in advance of the table for holding the guards down upon the ways. i

24. A grinding-machine, comprising a bed provided with ways" having requisite oilpockets, flexible strips serving as guards for the ways, springs secured to the guards, at one end thereof, a support for the o posite end of the guards, sliding table u on the bed, means for raising and lowerin t e guards to provide clearance for the tab e its travel, and means on the table for engaging the guard-support and moving the guards against the action of their sprin s.

In testimony whereofl I aflix'my signature in the presence of two witnesses.

JAMES ROBERT 00E.