US1840841A

US1840841A - Work handling mechanism for grinding machines and the like

Info

Publication number: US1840841A
Application number: US99287A
Authority: US
Inventors: Carle J Highberg
Original assignee: Heald Machine Co
Current assignee: Heald Machine Co
Priority date: 1926-04-02
Filing date: 1926-04-02
Publication date: 1932-01-12
Anticipated expiration: 1949-01-12

Description

Jan. 12, 1932.

0.4. 'HIGHBE RG 1,840,841

WORK HANDLING MECHANISM FOR GRINDING MACHINE 7S AND THE LIKE 9 Shets-Sheet 1 c. J. HIGHBERG -l,840,841 I WORK HANDLING MECHANISM FOR GRINDING, MACHINES AND THE LIKE Jan. 12, 1932.

9 Sheets-Sheet Original Filed A ril 2, 1926.;

fiadenz i Gar! e 1f @ey Jan. 12, 1932. Fue 1,840,841

WORK HANDLING MECHANISM FOR GRINDING MACHINES AND THE LIKE Original Fild April 2 1926 9 Sheets-Sheet' 3 wry/1111114 g 0 ,1 1 m-x 92 27-- J7 O l 26 K Care- 17.11% 226557" Jan. 12, 1932-. c J. HI GHBERG 1,340,841

WORK HANDLiNG MECHANISM-FOR GRINDING MACHINES AND THE LIKE Original Filed April 2, 192e 9' Sheets-Sheet 4 C'arZe Jli' ber' Jan. 12, 1932. c. J} HIGHBERG WORK HANDLING MECHANISM FOR GRINDING MACHINES AND THE LIKE Original Filed April 2, 1926 9 Sheets-Sheet 5 Jan. 12, 1932. c. J. HIGHBERG 1,840,841

WORK HANDLING MECHANISM FOR GRINDING, MACHINES AND THE LIKE Original Filed April 2, 1926 9 Sheets-Sheet 6 f I l y 6/ 35a Jafi. 12, 1932. c, J, HlGHBERG 1,849,841

WORK HANDLING MECHANISM FOR GRINDING MACHINES AND THE LIKE Original Filed April 2, 1926 9 Sheets-Sheet '7 Jam 1932- c. J HIGHBERG 1,340,841

WORK HANDLING MECHANISM FOR GRINDING MACHINES AND THE LIKE Original Filed April 2, 1926 9 Sheets-Sheet 8 gwumwtolo Jan. 12, 1932. c. J. HIGHBERG 1,840,841

WORK HANDLING MECHANISM FOR GRINDING MACHINES AND LIKE Original Filed April 2, 1926 9 Sheets-Sheet :9

' thereto.

Patented Jan. 12, 1932 onmzo STATES PATENT CABLE J1 HIGHBERG, -WORCESTER MASSAGHUSETTS, ASSIGNOB TO THE HEALD MACHINE COMPANY, OF WORCESTER, MASSACHUSETTS, A. COEPOBATICN F MASSA- CHUSETTS WORK HANDLING MECHANISM FOR GRINDING MACHINES AND THE 11m Application filed April 2, 1926, Serial No. 99,287. Renewed October 24, 1929.

The present invention relates to apparatus, applicable to automatic grindlng 'machmes and the like, for mechanically handling the successive workpieces that are sub ected to the operation of such a machine.

The invention is here shown in connection with an automatic internal grinding machine having the general construction and the capabilities of operation of machines such as are shown'and described in the patents of Heald, Guild, Burns and Garno, #1,751,202, dated March 18, 1930, and Kempton and Gallimore,

#1,731,719, dated October 15, 1929. With such machines it is possible to accurately grind successive similar workpieces to exacting of thechuck or work holder is performed mechanically, in timed and responsive relation to the usual movements of the grinding wheel carriage in the intervals between suc cessive grinding operations,-thus measurably increasing the productive-capacity of the machine by making its operation in every way continuous, and by eliminating the necessity for any interruption or intervention by an operator, once the machine has been adjusted and set up for the grinding of workpieces of a given type and size. The above and other objects are attained bythe instrumentalities which are set forth in detail in the following description, reference being had in this connection to the accompanying drawings, wherein Fig. 1 is a side elevation, partly in section,

showing the elements of an internal grinding machine, with the invention applied Fig. 2 is a top plan'view, partly in section, showing certain of the mechanism of Fig. 1 on a larger scale.

Fig. 3 shows the loading and unloading instrumentalities as viewed from the end of Figs. 1, 2 and 3, the machine the machine, the latter being shown partly in transverse section.

Figs. 4 and 5 are detail sectional views showing two difierent positions of the operating mechanism for the chuck or work holder of the machine.

Fig. 6 is a fragmentary plan view, on an enlarged scale, of the magazine or hopper for the unground workpieces which are to be operated upon, successively, by the machine. F Fig. 7 is a side view of the parts shown in Fig. 8 is a fragmentary detail view of a portion of the magazine.

Fig. 9 is a fragmentary plan view of mechanism situated at the lower end of said magazine.

Fig. 10 is a side view, partly in section I showing the operation of the loading an unloading elements in relation to the lower end of said magazine.

Fig. 11 is a view similar to Fig. 3, showing a modified form of the invention. ig.- 12 shows the parts disclosed by Fig. 11 as viewed from the rear of the machine.

Fig. 13 is a sectional view on the line 13-13 "of Fig. 1, showing the transverse feeding mechanism with automatic repositioning means.

Fig. 14 is\a sectional view on the line 1414= of Fig. 13.

Fig. 15 is a fragmentary sectional view on the line 1515 of Fig. 13.

Fig. 16 is a fragmentary view of the front of the machine, showing the location of a certain magnet and the lever it operates.

Fig. 17 is a plan view of the work calipering mechanism.

Fig. 18 is an elevation of the right hand side of said mechanism. 7 Fig. 19 is a view of the calipering mechanism detached from the machine.

Fig-20 is a wiring diagram.

Like reference characters refer to like parts in the different figures.

Referring to the drawings, particularly to provides the usual reciprocatory table or carrla e 1 which is ordinarily provided in interna grinding machines. In such a machine, either the tions of the latter being utilized in either case to produce a relative traversing movement between the grinding wheel and the work. As here shown, the table 1 supports and carries a wheel head 2 of the usual construction, while the work which is to be operated upon is held in a work head 3, the latter being carried by a bridge 4 which spans the slideways provided by the machine frame for the back and forth movement of the table 1.

The work head 3 provides the usual instrumentalities for supporting and rotating the workpiece that is to be ground. As shown in Fig. 1, a hollow rotary work spindle 5, j ournalled in the work head 3, has secured to its end the usual chuck-encircling fixture 6, the latter providing, interiorly, a"

plurality of slidable work engaging jaws 7. These jaws are pivotally secured to a member 8' carried by a rod 9, which is slidably mounted in the bore of the spindle 5;

' as 1s usual in the operation of such a work holding device, the retraction of rod 9 causes the jaws to seize and center the workpiece (1, thereby procuring itsrotation with the spindle 5, while the opposite movement of rod 9 to the right, Fig. 1, causes the jaws 7 to open, under the influence of a set of springs, one of which is shown at 10, thereby releasing the workpiece a and allowing it to be withdrawn from the chuck.

The back and forth movement of the table 1, to cause the rotating grinding wheel 11 to make the r uired interior traverse of the rotatin wor piece a, may be imparted in any we 1 known manner; in thepresent instance, a fluid pressure controlling and reversing mechanism is employed, the same as illustrated and described in United States Letters Patent No. 1,582,468 to Heald and Guild, granted April 27, 1926; itbeing noted that the valve and associated mechanism of said patent for stopping the table at the outward end of its long stroke is not employed in the present machine, since the table 1 is automatically reversed at its outer limit of extended travel, as will hereinafter appear. Such mechanism procures the reversal of the table 1 at each end of the 'latters normal working stroke, by the alternate engagement of spaced adjustable dogs 12 and 13 with a suitable reversing member 14. Also, as described in anapplication of Heald and Guild, Serial No. 25,900, filed April 25, 1925, I desirably utilizemechanism adapted, at an intermediate point in the grinding of each workpiece a, to move a wheel dressing device 15, Figs. 2 and 3, intothe path of, grinding wheel 11,the latter, for the purpose of being dressed and trued by said device 15, undergoing, automatically, a single amplification of its normal working stroke-in the chine of said Heald, Guild, Burns and Garno patent, the present machine may be equipped with a work calipering member 16, Fig. 2, whose movement to a predetermined position, in response to the progressive enlargement of the hole in the workpiece a, procures, automatically, the above described single amplification of the stroke of table 1, simul taneously with the disposal of dressing device 15 in operative position,thus to subject the grinding wheel 11 to a dressing and truing operation in advance of the final and finishing cuts taken on the workpiece a to bring it to the required predetermined size. Following this dressing operation, the dressing device 15 automatically returns to inoperative position, and the grinding wheel 11 automatically resumes its normal working stroke in the hole of, workpiece a, as a result of which the calipering member 16, in response to further progressive enlargement of said hole, arrives at a position which signifies the completion of the grinding operation on said workpiece, through the latter having reached the desired predetermined internal diameter. When the calipering member 16 reaches this position, it automatically procures, through the completion of an electric circuit and the instrumentalities described in said Heald, Guild, Burns and Garno patent, the full withdrawal movement of table 1, to carry the grinding wheel 11 out of the workpiece a and well beyond the dressing position, and simultaneously the withdrawal of the calipering. member 16 from said workpiece so that the latter can be removed from the chuck. As hereinafter described, the completion of this electric circuit automatically pro cures, in the present machine, the lateral repositioning of the grinding wheel, so as to let chine, such as the present embodiment of my invention is, must provide for the substitution, at the proper moment, of a fresh unground workpiece for the one that has been ground to the desired size, and since this action is responsive, in the present instance, to a caliper 16 which makes contact with successiveworkpieces, it is necessary to describe so much of the said invention of Heald, Guild,

Burns and G'arno as will describe how the caliper 16 is brought into position and then removed. so that each successively finished workpiece a can be automatically removed from the chuck. I

As shown in Figs. 2, 17 and 18, the member 16 is to all intents and purposes a lever, said member, for the movement required of it to maintain a point 16a in constant contact with the interior of a workpiece a, being supported by a pair of flexible U-shaped

flat springs

150 and 151, which springs cross each other, as shown in Fig. 17, and are attached to two adjacent sides of a rectangular block portion 152 of member 16. At their other ends, the crossed

springs

150 and 151 are attached to two

inner surfaces

153 and 154 of a box 155, these

surfaces

153 and 154 being at right angles to each other, and the hr x 155 providing an opening 156 of sufficient- 'ze to permit the inward extension 16?), of iT-mber 16, to

move freely about the pivotal axis which is afforded by the intersection of the planes of the

U-shaped springs

150 and 151. This pivotal movement-is accomplished by the flexing of these two springs, and takes place in the entire absence of lost motion since there is no bearing or pivot pin. Consequently, any movement of the extension 166 of member 16 within the box 155 is invariably in exact accordance with the movement of calipering .point 16a, in maintaining contact with the surface of the the workpiece. 7

Such motion of the member 16 is adapted gradually enlarging hole in to be transmitted to an indicator lever 157,

pivoted at 158 within the box ,155, with its free end adapted to move across the graduations'of a suitable scale 159. Lost motion may be eliminated at bearing158'by a spring 160. The connection between extension 166 and indicator lever 157 is made by a spring 161, which draws the parts together and maintains the lever 157 in contact with the end of a screw 162, said screw being adjust is multiplied manytimes in being transmitted to the indicator lever 157, as willbereadily understood.

In the operation of the mechanism, the calipering point 16a maintains contact with a given workpiece a, the movement of member 16 for this purpose being obtained by the pressure of a spring 165, and such movement being transmitted through the above described connections to the indicator lever 157.

grindingof each workpiece, to cause cessation of the grinding when each workpiece reaches a predetermined and desired size. To this end the lever 157 carries an electrical contact 166 for closing an electric circuit that controls the operations involved in cessation of grinding. In the path of this contact, the box 155 provides a stationary terminal contact 167. Before describing the electrical circuits which contain the contact points 166 and 167, the further construction and operation of the work calipering mechanism will beset forth.

The box 155 which carries the member 16 and indicator lever 157, as above described, is adjustable longitudinally on a supporting bracket 168, such adjustment being effected by a screw 169, turned by a hand wheel 169a, said screw passing through a threaded lug 170 of bracket 168; after the box 155 has been adjusted as above described, it is firmly fastened in position by tightening the

bolts

171, 171, which are threaded into the bottom of the box and pass through

elongatedslots

172, 172 of bracket 168, see Figs. 17 and 18. Said bracket 168, which carries box 155, is rigidly attached to the upper end of a spindle 173; the latter being ournalled in a bearing sleeve l74 provided by a bracket 175 which, as best shown in Fig. 2, is bolted to the bridge 4. Preferably the upper part of spindle 173 (not shown) is frusto-conical in shape, and seats against a correspondingly formed portion in the bearing sleeve 174, the spindle being drawn tightly against said frusto-conical seat by a spring 176 (Fig. 18) which thrusts against the outer race of a ball bearing 177, the inner race being clamped between a shoulder on the spindle and a nut 178. This construction is adopted, of course, to keep the axis of oscillation of the box 155 accurately fixed or determinable upon the machine frame.

This swinging or oscillating movement of the box 155 takes place in response to movement by the table 1 as follows:-A split collar 179 surrounds that portion of the bracket 168 that is secured to the spindle 173, said collar being drawn into tight engagement with said bracket by a bolt 180. Extending from saidcollar is an arm 181 carrying a roller 182 which, in the normal work engaging position of the calipering point 16a, lies in the path of, but spaced at some distance from, a cam bar 17' attached to the table 1. In this normal work engaging position, a strong coil spring 183, surrounding the sleeve 174 and attached thereto, exerts its force against arm 181 to rotate the latter counterclockwise. Said arm is firmly attached to the bracket 175 by collar 179 and bolt 180, and thus the force of spring 183, exerted on said arm, maintains the calipering tached to the casting 175. See Fig. 19.

and indicating mechanism as a unit in the position shown in Fig. 17, where a lug 184, on arm 181, brings up against a fixed stop 185 formed on .a bracket 185a which is at- At the end of each grinding operation, when the table 1, as hereinafter described, is automatically given an extended movement to the right, the cam bar 17, carried by said table, strikes roller 182 and rocks the arm 181 in a clockwise direction .against the force of spring 183. thereby swinging the entire calipering and indicating mechanism as a unit from the position shown in Fig. 17 to the position shown in Fig. 2, thus allowing the finished work-piece a-to be withdrawn and a new workpiece to be inserted in the jaws 7 of the chuck 6, as will be described.

- In connection with the above described swinging movement of the calipering and indicating mechanism, the work calipering point 16a, desirably a diamond, is automatically disposed in a position which prevents it, or the member 16, from forcibly engaging the mouth of a workpiece in the act of entering the same. If some such means were not provided, the member 16'might be entirely prevented from entering a fresh workpiece 01, or, in the act of entering, the calipering point 16a might be chipped or broken off.

To prevent such occurrences, a rod 186 having a head 187 provides bearing

portions

188 and 189 for sliding movement in bearing holes provided by opposite sides of the box 155. Between the bearing

portions

188 and 189,.the rod has a reduced neck 190, forming a shoulder 191 for cooperation with a downward projection 192 of the extension 16?). A spring 193, encircling the rod 186 and thrustingoutwardly against the head 187 thereof, draws the shoulder 191 against projection 192 and, in the inoperative position of the calipering and indicating mechanism shown in Fig. 2, this action of spring 193, being stronger than the action of spring 165, rocks the member 16 in a clockwise direction, thus to hold the calipering point 160 in an inoperative position, so that it can enter, without striking, an unground workpiece (1.

However, when the member" 16 and the calipering point 16a have entered the said unground workpiece, the head 1870f rod 186 strikes a hardened steel stop plate 194 which is secured to the bracket 185a, and this action forces the rod 186 inwardly of the box 155 and relieves the member 16 of the influence of spring 165. It will be readily understood that head 187 and plate 194 come together just before the lug 184 strikes the stop 185, and that the coil spring 183 is stronger than the spring 193' around rod 187, so that the latter spring cannot prevent the proper positioning of the box 155 as determined by the stops 184-185. See Fig. 19.

The above action releases the member 16 so that the caliper point springs toward the internalsurface of the workpiece it has entered, and from that time till the box 155 is again swung outwardly by the cam bar 17 on the table. (which only happens when the grinding of the said workpiece is finished) the. point 16a is in engagement with the work, and the indicating and contact making lever 157 moves in accordance with the enlargement of the bore of the workpiece.

When said lever 157 has moved far enough to make contacts between

points

166 and 167, an electric circuit is formed which causes the table 1 to undergo an extended movement to the right, carrying the grinding wheel 11 out'of the workpiece, well past the now inoperative dressing device 15 and moving the cam bar 17 into contact with the roller 182 to swing the box 155 outwardly, as set forth. As shown in the wiring diagram of Fig. 20, electric current may be supplied by a generator G driven continuously by any suitable means. One terminal of this generator is grounded, as clearly shown, and thecontact point 166 is also grounded, by reason of not being insulated from the lever 157. The stationary terminal 167 is connected by

conductors

195 and 196 to the coils of a solenoid- 138 and an electromagnet 197, respectively. The return leads from said solenoid and electromagnet, numbered 198 and 199, go to the left hand bar 200 of a three-way switch 201. Bar 200 is, when

contacts

166 and 167 come together, electrically connected to a central bar .202 of said switch 201, by reason of certain instrumentalities.brought into operation coincident with the automatic dressing action referred to, and as bar 202 is connected by a conductor or lead 203 to the generator, the circuit through the solenoid 138 and the electromagnet 197 is complete, and said electric devices are energized. However since, for the purposes of the present invention the dressing instrumentalities could be entirely dispensed with, and since it is not proposed to' describe themfurther, it may be considered that the conductors 198 and 199 are directly and at all times connected to the conductor 203, and as indicated by the dotted line in Fig.20, and that the switch 201is non-existent.

The electromagnet 197 is located, as shown in Fig. 16, on the front of the grinding machine, being preferably inclosed in a casin 204 to keep out dirt. Above the magnet 197 is an armature'205 having attached thereto a lever arm 206, these parts being pivotally mounted for movement on a pin 207. The upward movement of arm 206, due to the energizing of electromagnet 197 and the conse quent attraction of armature 205, interposes the freeend of. said arm in'the path'of table dog 13, see Fig. 1, which latter, as heretofore pointed out, normally, on the right hand aeeaeer working stroke of the table, strikes and moves the reversing member 14 to cause a reversal in the direction of table travel. Said dog 13, unlike dog 12, is a pivotally mounted dog, being pivoted at 208 to a carrying block 209', and hanging by gravity against a pin 210.- When the arm 206, as above described, moves upwardly into the path of dog 13, the free end of said dog,-on the right hand movement of the table, engages with and rides upon the upwardly inclined surface of arm 206. Such elevation of the dog 13 carries it'clear of reversing member 14, and thus when the

contacts

166 and 167 come together to energize the magnet 197, the table 1 is automatically prevented from reversing its travel at the right hand limit of its usual working stroke; instead said table, through the disposal of dog 13 in a wholly inoperative posi tion, continues its movement to the right,'carrying the grinding wheel out of the work and well past the dressing device 15, said table finally being reversed by a remotely positioned dog 111, whereupon the table 1 returns, carrying the grinding wheel 11 into a new workpiece a, the dog 13 lifting and dropping behind the member 14, thus again' placing said reversing member between the dogs 12 and 13 that control the normal work traverse.

The present invention is concerned with instrumentalities brought into operation by said full withdrawal movement of table 1 for mechanically effecting the removal of said finished workpiece from the chuck and for mechanically disposing an unground work piece in said chuck, preparatory to the next grinding operation of the machine. To this end, as shown in Figs. 2 and 3, the .table 1 has secured thereto a member 17, the latter providing an elongated cam groove or slot having a straight longitudinal portion 18 and two offset portions 19 and 20, the former being connected to portion 18 by a portion 21 of relatively slight deviation, and the portion 20 being connected to portion 19 by a portion 22 of sharper deviation. The cam member 17 is adjustable longitudinally of the table 1, this adjustment being secured by the passage of the retaining bolts 23, 23 through elongated slots 24, 24 provided by said member. Working in the cam of member 17 is a roller 25, the latter being carried by a lever 26 which is pivoted at 27 to the under side of a casting 33 attached to the work head 3. The lever 26 is connected by a link 28 to a rocker arm 29 extending from a vertically disposed rock shaft 30. Said rock shaft 30 is journalled in suitable bearings provided by upper and

lower extensions

31 and 32 of the casting 33 which is the usual water guard casting that surrounds the work holder or chuck. The upward extension 31 of said castin provides suitablebearings for another rock shaft 34, whose axis, lying in a plane at right angles to the axis of work spindle 5, has a decided inclination from the vertical, as best shown in Fig. 3. The shaft 34 carries a. bevel tion and retention of a work engaging plug 38, said plug being somewhat smaller than the holes of the workpieces a, a and providing a spring, or other suitable friction gripping device 39, Figs. 1 and 10, which is adapted to frictionally support a workpiece a; on the plug when thelatter is entered into the hole of said workpiece. In the normal grinding operation of the machine, when the rotating grinding wheel 11 is making its usual reciprocator'y working traverse Within the rotating workpiece a, the roller 25 is engaged wholly by the longitudinal cam portion 18, in consequence of which no movement is imparted to the

shafts

30 and 34,said shafts remaining stationary and holding the arm 37 in the position illustrated by full lines at A in Fig. 1. This position is also maintained by said arm during the single amplified dressing stroke of grinding wheel 11, which may occur, as above stated, at an intermediate point in the grinding of each Workpiece,the longitudinal cam portion 18 bein of suflicient length to permit such ampli cation of the stroke of table 1 without having the roller 25 engaged by the cam portion 21.

However, onthe full withdrawal movement of table 1, brought about as above described at the completion of the grinding operation,

.the roller 25 is engaged by the cam portion 21,

this causing initially the movement of arm 37 from the position A to the dotted line position B, Fig. 1, wherein the plug 38 and spring 39 are thrust into the hole of. the

pressure devices may be employed, if'desired', for the movement of rod 9 which, as described above, renders the chuck jaws 7 operative and inoperative; Said rod 9, extending through the hollow work spindle5, is securedv at its outer end to a piston 40, the latter-working in a cylinder 41. The piston rod or extension 42 of said piston provides a pair ofpassages 43 and 44, terminating, respectively, on opposite sides of said piston within the cylinder 41. The passage 43 is connected by flexible piping 45 to a valve casing port 46,.and the passage 44 is connected by flexible piping 47 to a valve casing port 48.

are

' 335 As shown in 4 and 5, suitable fluid y The valve casing 49, which provides these

ports

46 and 48, is preferably mounted, as shown in Fi 3, on the frame of the machine below the ta 1e 1, and a cylindrical valve 50, contained in said casing 49, occupies, during the grinding operation, the position illustrated in Fig. 5, where a passage 51 of said valve connects the port 46 with a source 52 of fluid pressure supply, thus admitting the pressure fluid through passage 43 to the right and side of piston 40, and retaining said piston in its left hand position, as shown in Fig. 5; drawing back rod 9 until the fingers 7 grip the workplece a; in this position, the pressure fluid exhausted from the other side of piston 40 through passage 44 passes out by an exhaust recess 53 of valve to an exhaust port 54 of the valve casing. When the valve 50 is rocked from the position shown in Fig. 5 into the position shown inFig. 4, the pressure fluid flows to port 48, and thence through the passage 44 to the left hand side of piston40, thus moving rod 9 to the right, to release the

jaws

7, 7 from their grip on the workpiece a. The pressure fluid which is displaced by this right hand movement of piston 40 returns to the valve by passage 43 and is exhausted through a valve recess 55 connecting the port 46 with an exhaust port 56.

Substantially coincident with impalement of the workpiece a on the plug 38 on the above described down swing of arm 37, the rotation of work spindle 5 is stopped,-this stoppage being brought about in a manner well known in machines of this class, namely by a cam, not shown, on the table 1 which unclutches said spindle from its operating means, not shown, and simultaneously applies a brake, not shown, to said spindle. The arm 37 remains stationary during the brief. engagement of cam portion 19'with roller 25, and in this period of dwell an arm '57, Fig. 3, depending from table 1, strikes a projection 58 on the shaft of valve 50, to rock said valve from the position shown in Fig. 5 into the position shown in Fig. 4, thereby releasing the work-piece a from the rip of the chuck jaws 7 7, as above describe Following this, on the continued withdrawal movement of table 1,. the roller 25 is engaged by the cam portion 22, this engagement procuring a reverse rotation of the

rock shafts

30 and 34 and a consequent upward swinging of the arm 37 whose plug 38 carries with it the finished workpiece a which has just been released from the chuck. The cam portion 22 being considerably longer than the cam portion 21,-the u ward swing of arm 37 continues beyond t e position A and carries the plug 38 between a pair of spaced

jaws

59 and 60, to be hereinafter more fully described. The spacing of these jaws is Suficient to permit the passage of the plug 38 between them, but is not sufipcient to permit the passage of the workpiece a which is fricemma tionally held, by spring 39, on said plug. Consequentl the

jaws

59 and 60, by the eng'agement 0 their under surfaces with the face of workpiece a, are efiective to strip said workpiece from the plug 38, as a result of which the finished workpiece drops into an inclined chute 61, Fig. 3, which is'supported in any suitable manner, as by a ing 62 on the upper extension 31 of water guard casting 33. Each finished workpiece, as thus mechanically removed from the machine, is thus discharged into the chute 61, which serves for the conveyance of said workpieces, by gravity, to any suitable receptacle, not shown. F

As shown inlFigs. 3, 6,7 and 9, the jaws 59 and *above referred th,"are supported by a member 63 which is secured to the under side" of an-'" inclined bracket 64 rising from the extension 31. On its other side, said bracket 64' supports a suitable chute or hopper 65 into which the unground workpieces a, a are loaded,the floor 66 of said hopper being inclined, and 'having

suitable side walls

67, 67 for the guidance and confinement of said workpieces in their gravity descent towards the lower end of said hopper, contiguous to said

jaws

59 and 60. The

jaws

59 and 60 are so shaped as to form a continuation of and a partly closed end for the chute 65. As best shown in Figs. 7 and 8, a stop 68 normally occupies a position wherein it is engaged by the upper edge of the lowermost workpiece in the hopper 65, thus interposing an obstruction to the movement of all the workpieces in said hopper, and at the same time preventing said lowermost workpiece from reaching the lower end of the hopper where its presence would interfere with the free passage of the arm 37 and plug 38 through the

jaws

59 and 60 on the above described upward swing of said arm.

The'stop 68 is carried by a rod 69, the latter being slidablein an extension 7 O of the bracket 64. Said rod 69 has secured thereto a head 71, whichprovides an adjustable screw 72 adapted to be engaged by the arm 37, Fig. 10, just before the arm 37 reaches the limit of its up ward movement, as the roller 25 passes out of the cam portion 22 and into'the cam portion 20. The engagement-ofarm 37 withscrew 72 moves the rod 69 from its normal position, illustrated in Fig. 7, into the posi-v tion shown in Fig. 10, and this movement c'ar-' lies the stop "68 away from contat with the- Ill lowermost workpiecea. in the hopper 65, thus freeing said lowermost, work iece and allowing it to slide bygravity. own intb' the position illustrated at a in-Fig. 10, supported now by the

jaws

59 and 60. At the same time, a rod 73 carried by the head 71, undergoes the same retraction as the stop 68; norma ly this rod 73 presses against a spring 7 4' beneath the floor 66 of the hopper and holds a stop 75 carried by'said spring in inoperative position,

as shown in Fig. 7. However, when rod 73 workpiece onto the inwardly tapered suris retracted, as shown in Fig. 10, the spring 74 thrusts the stop 75 above the plane of the floor 66 of the hopper and in front of the next lowest workpiece a and thus prevents said workpiece and the workpiece above it from moving past the retracted stop 68.

The table 1 now having reached the limit of its outward movement, with the cam portion 20 engaging the roller 25, the aforementioned dog 111 on table 1 strikes the member 14, thereby initiating the return movement of said table to carry the grinding wheel 11 back into position for operation on the next workpiece. On this return movement, as soon as the left hand end of cam portion 22 reaches roller 25, the down swing of arm 37 begins, and the initial downward movement of said arm, carrying said arm away from screw 72, allows rod 69 to return to its normal position under the influence of a spring 76 encirclingsaid rod and bearing against a shoulder 77 thereof. This movement of rod 69 simultaneously lowers the stop 75 into inoperative position and lowers the stop 68 into operative position, whereupon the workpiece a slides down against stop 68 in position to be released by said stop on the next cycle of operations of the mechanism. As the arm 37 continues to swing downwardly,'the plug 38 is thrust into the hole of workpiece a Fig. 10, the latter, as above described, having descended to the lower end of the hopper which is constituted, as shown in Fig. 7, by the two

jaws

59 and 60. These jaws provide side ledges or flanges 110 constituting a continuation of the side walls 67 of hopper 65, and as shown in Fig. 9, the ledges 110 are curved inwardly at the tips of the jaws so as to arrest the workpiece a in its descent and hold it in position to be impaled on the descending plug 38. The inner curved surfaces of the

jaws

59 and 60 support the workpiece a with its bottom substantially flush with the floor 66 of hopper 65, this support being afforded by the inward taper of said surfaces, as shown at 78, Figs. 7 and 10, in consequence of which the space between said jaws, in their normal positions, is not sufiicient for the workpiece a to pass through. The

jaws

59 and 60 constitute the terminal portionsv of two members 79 and 80 respectively, which are pivoted on a stud 81 carried by member 63, said members 79 and '80

havin'g tailpieces

82, 82, whichen gage on opposite sides of a fixed pin 83, forming a limit stop for the approach, toward each other, of the

jaws

59 and 60. A spring 84' connects the two members 79 'and 80 and draws the two jaws yieldingly to ward each other, so that the workpiece a is held by said aws in the path of the descending plug 38, as shown in Fig. 10.

As the descending arm 37 thrusts the plug I 38 into the workpiece a the downward pressure of said arm is transmitted through said faces 78 of the

jaws

59 and 60, producing a wedging action which, as the downward swing of arm 37 continues, distends said jaws andpermits the workpiece to pass between them,the resistance of spring 84 tothis distention, however, being sufficient to insure the complete entry\of plug 38 into the workpiece, so that the spring 39 of said plug se-- cures a firm grip whichv prevents the workpiece from falling off the plug afterbeing carried clear of the jaws. The latter then automatically return, under the influence of spring 84:, to normal position, in readiness to serve as a means for stripping the workpiece after its grinding, from said plug, on the upward swing of arm 37, as heretofore described. I

. lVith the table 1 still moving to the left, the down swing of arm 37 continues until the roller 25 reaches the ri ht hand end of cam portion 22, at which time said arm 37, carrying the unground workpiece a comes to rest in the position marked B, Fig. 1, the

workpiece being thus disposed between the

distended chuck jaws

7, 7. In the brief dwell provided by the cam portion 19, the arm 57 of table 1 strikes another projection 58 on the shaft of valve 50, see Fig. 12, rocking said valve from the position illustrated in Fig. 4 into the position illustrated in Fig. 5, and thereby moving the rod 9 to the left, so as to procure the engagement and retention of the workpiece by the chuck jaws7 ,7. F ollowing this, as the cam portion 21 becomes operative on the roller 25, the arm 37 swings upwardly, the plug 38 withdrawing from its frictional engagement with the ,workpiece, since the latter is held firmlyrby the

chuck jaws

7, 7; this upward swingof arm 37 returns it to the position indicated at A, Fig. 1, at which time the roller 25 is once more engaged by the longitudinal cam portion 18, which prevents any further movement of said arm 37 until the grinding operation on said workpiece has been completed. Substantially coincident with the return ofarm 37 to the position indicated at A, Fig. 1, the clutch or work spindle 5 is again made operative to cause rotation of said spindle, and the calipering member 16, as described automatically enters the hole in the workpiece; thereupon the grinding wheel 11 enters said hole in the same way with an overhead hopper,

not shown, into which the unground workpieces are loaded, and with a stripping device in the form of the

jaws

59 and 60 for discharging each finished workpiece removed by said arm" into a suitable trough or chute 61. 34, and the movements of said shaft, to secure the same cycle of operations for the arm 37 as are above described, are obtained in the following manner The reciprocatory table 1 is formed on its under side with .a rack 17a, the latter having in mesh therewith a gear 176 secured to a shaft 90, which is suitably journalled in the stationary framework of the machine. At its other end the shaft 90 carries a plate 91, to which is secured a cam disk 170, the latter being angularly adjustable with respect to the plate 91 through the medium of

elongated slots

23a, 23a provided for the passage of the retaining screws or bolts 24a, 24a. Said cam disk 170 has formed thereon an irregular cam track 18a, in which rides a roller 25a, carried by the end of a pivoted arm 26a. The latter is connected by a link 28a, to an arm 29a on a rock shaft 30a, whose other end provides an arm 101 formed with a gear segment 36a that meshes with a suitable pinion a on the rock shaft 3 1.

In the normal grinding operation of the machine, and also during the automatic dressing of the grinding wheel, the roller 25a rides in the concentric portion 18a of cam groove 18a, in consequence of which no rotation is imparted to the rock shaft 30a, and the arm 37 remains stationary in a position corresponding to that marked A, in Fig. 1. The full outward movement of table 1, initiated by the completionof the grinding operation on a given workpiece, secures a single counterclockwise rotation of the cam disk 1'70, and in this rotation, the engagement of cam portion 21a with roller 25d, secures the down swing of arm 37 into position for its plug to impale the finished workpiece. Then, in the dwell provided by cam portion 19a, a pin 5%, carried by plate 91 and operating in timed relation to cam plate 17 0, strikes one of the projections 58 of the oscillatory valve 50, to rock said valve from the position illustrated in Fig. 5 into the position illustrated in Fig. 4, thereby releasing the workpiece from. the-chuck jaws '7, 7. Continued coun'terclock wise rotation brings the cam portion 22ainto engagement with the roller 25a, this causing the upward swing of arm 37 on which the impaled finished workpiece is stripped'from said arm, as heretofore described, and on which the lowermost unground workpiece in the hopper is separated from the other workieces in the hopper and allowed to descend into position to be seized by said arm. At this time, the table 1 reverses its movement, causing clockwise rotation of cam disk.17c, and cam portion 22a being then in engage ment with roller 25a, secures the down swing of arm 37, on which said arm picks up the The arm 37 is mounted on a rock shaft screw shaft 113, but at a We segregated workpiece from the hopper and carries it into chuckin position. Then, during the engagement 0 cam portion 19a..with roller 25a, the chuck aws are again made operative, following which, on the engagement of cam port-ion 21a with rolled 2511, the arm 37 moves back up into the'position marked. A in Fig. 1.

In both embodiments of the invention, some means must be provided to retract the wheel I 11 laterally prior to its movement into a fresh and unground workpiece (1. Such means, includin also the normal and usual lateral feeding mechanism, will now be described. I do not claim such wheel retracting mechanism per se, but only incombination with the other instrumentalities herein shown and described.

Referring now to Figs. 1, 13, 14 and '15, the wheel head 2 is mounted to move transversely of the table 1, the said table 1 for that punpose providing ways, not shown, as such is the usual and ordinaryconstruction of these parts. The wheel head 2 carries a nut or other equivalent device 112 which is internally threaded, see Fig. 13, and passing therethrough is a screw shaft 113 which is carried by the table 1. 'Rotation of this shaft 113 is I adapted to feed the wheel head 2 laterally of the table 1, the direction of travel being, of course, determined by the direction of rotation. In this particular mechanism, a sleeve i 114 surrounds the front portion of shaft 113 and is fastened to it, said sleeve 114 providing a spur gear portion 115. A second sleeve 1 16 surrounds shaft 113 and provides a gear portion 117, but these parts are stationary. A pair of integral'gears'118 and 119 mounted to turn on a" stud 120; provide, with the other parts, a convenient differential reduction gearing so that rotation of the annular hand wheel member 121 to which said stud 120 is attached will result in rotation of said I much reduced rate. A ratchet wheel 122 is also attached td the hand-wheel member 121', and automatic l rotation of said ratchet to feed the wheel head 2 to carry the wheel '11- into engagement with the wor iece is effected as follows v The bridge 4, or any other convenient stalll tionary part of the machine, carries a bar 123 on which is adjustably mounted a'cam piece 124. Pivotally mounted at 125 (see Fig. 1, dotted lines) is a member 126. Said member 126 carries a roller 127 and also a pawl 128 which is spring pressed towards the ratchet 122, but in the position shown in Fig. 1, with the roller 127 not engaging the cam 124, saidpawl 128 is prevented from engaging said ratchet 122 by a shield device 129.

From the foregoing brief description of parts, it will be apparent that longitudinal reciprocation of table 1 results in lateral feeding. of the wheel '11, said feed at the left hand extreme travel of table 1, the cam 124 being adjustable for the purpose of causing the feed to occur at this point regardless of the size or depth of the particular work as the pawl 128 is concerned.

-pawl 136, see Fig. 15. Said pawl 136 Referring now to Fig. 13, a coil spring 130 is provided to automatically reposition the wheel head 2. Said coil spring 130 is fastened at 131 (see Fig. 15) to a non-rotatable part ofthe table 1. The other end 132 of said spring is fastened to an annular memher 133, rotatably mounted on the hand wheel casting 121. As shown in Fig. 14, the latter 0 rries a ratchet gear 134, while a rotatably mounted member 133a fastened to the member 133 carries a pawl 135. These face in such a way that when the spring 130 is allowed to unwind, the member 133a, which then turns'ina counterclockwise direction, carries with it the hand wheel 121a and ratchet 122.

During the grinding operation, the ratchet 122 is held from any retrograde motion in response to the means just described, by a formed on the end of .a core piece 137 inside a solenoid 138. When the workpiece has been ground to the finished size, the solenoid 138 is energized, as already set forth, so that as the table 1 moves outwardly or more accurately, when the electric circuit is made which will cause it to move outwardly, the pawl 136 is lifted. This allows the wound up spring 130 to come into action, and the hand wheel 121a and associated parts are moved in a retrograde direction, so that the wheel 11 can enter a subsequent unground.

workpiece.

As the spring 130 builds up quite a momentum in the hand wheel 121a and member 121, bumper means is provided to bring the parts to a stop without damage. To-this end the member 13311 has track grooves 139 thereon, extending partially around it, and a sto 140 is mounted in said track 139, beingadiustably fastened at any position by means of a hand screw device 141 cooperating with worm wheel teeth 142 in the outer periphery of member 133a. The sto clined plane surface 143 a apted to strike a bumper lever 144, pivoted at 145 on the table 1. The impact compresses a which takes the shock.

Assuming the machine to be put in oper-' ation with a fresh grinding wheel 11 and the cross-feed mechanism just described to be set so that when the first workpiece reaches finished size, the parts will be in the position shown by Fig. 14, and it is obvious that in the case of the second workpiece, the crossfeed mechanism will have to be advanced slightly beyond the said position of the hand wheel member 121 in said figure, because of 140 has an in-.

spring 146 the reduction of'the grinding wheel 11 on account of wear and dressing. But the members 133 and 13311 cannot be moved past said position of Fig. 14, for at that point a cam surface 147 on the upper end of pawl 135 engages a stationary cam surface 148 to lift said pawl 135, until the edge of pawl 135 is lifted to clear .tooth of ratchet 134. This releases the rings 133 and 13341 which will then turn back counterclockwise under the influence of the wound-up spring 130. This retraction is limited to one tooth of ratchet 134 by the spring 149, which forces pawl 135 to follow the inclined back of ratchet tooth 134 and being allowed to do so by the inclined cam surfaces 147 and 148 as the ring 133a retracts. Thus the spring 130 is always wound to an even tension at said finished size. The spring 149 presses the pawl 135 into engagement with the ratchet 134, providing enough resistance to hold the hand wheel 121a and casting 121 when the members 133' and 133a are stopped by the bumper described.

Within the contemplation of my invention, the new automatic work-loading means may be used in combination with the wheel repositioning means just described, or with strumentality, a work-holding chuck, and

means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, including means for causing a substantial, separation between said instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, means for determining when a workpiece has been ground to the desired size, a work carrier, and means set in operation by said last named means ,and brought. into operation during said movement of separation for causing said work carrier to move into engagement with the work in said chuck and disengage the work from the chuckand move out of the way of the grinding instrumentality.

2. The combination with a grinding instrumentality, a -work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, including means for causing a substantial separation between said-instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, of a work carrier, and'means directly actuated by said movement of separation for causing said work carrier to move into engagement with the work in said chuck, and disengage the work from the chuck and move out of the way of the grinding instrumentality.

3. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding 'instrumentality and said chuck, includingmeans for causing a substantial separation between said instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, of a work carrier, means actuated by said movement of separation for moving said work carrier to said chuck where it receives a ground workpiece from said chuck, and for moving said carrier away from said chuck, and stripping means for removing the ground workplece. U

' 4. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, includingmeans for causing a substantial separation between said instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, ofmeans for determining when a workpiece has been ground to the desired size, a work carrier, means set in operation by said lastnamed means and functioning during said movement of separation for moving said work carrier to said chuck, where it receives a ground workpiece from said chuck, and for su seqgiently moving said carrier away from sald c uck, and stripping means for removmg the ground workpiece from said carrier.

5. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentallty and said chuck, of means for determining when a workpiece has been ground to the desired size, a work carrier, means set in operation by said last-named means for moving said work carrier to said chuck, where it receives a ground workpiece from said chuck,

I and for subsequently moving said carrier away from said chuck, and stripping means for removing the ground workpiece from said carrier.

\ 6. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relativereciprocatory motion between said grinding instrumentality and said chuck, including means for causing a substantial separation between said instrumentality and chuck followed by a return motion to bringsaid parts together again for further relative reciprocatory motion, of a magazine, a work carrier, means actuated by said movement of separation for moving said work carrier to said chuck and then past said magazine, a ground workpiece being thereby'removed from said chuck and discharged from the machine, and means actuated by the return motion for moving said carrier past said magazine, then to said chuck, andfinally out of the proximity of said chuck, whereby a fresh workpiece is transferred to said chuck, and the carrier is removed from the relative path of travel of said grinding instrumentality.

7. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and chuck, includmgmeans for causing a substantial separation between said instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, of a magazine, a work carrier, means actuated durin said movement of separation and return for moving said work carrier to said chuck and then past said magazine, a ground workpiece being thereby removed from said chuck and discharged from the machine, and further means actuated during said movement of separation and return for moving said carrier ast said magazine, then to said chuck, and nally out of the proximity of said chuck, whereby a fresh workpiece is transferred to said chuck, and the carrier is removed from the relative path of travel of said grinding instrumentality.

8 The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentalityand said chuck, of means for determining when a workpiece has been ground to the desired size, a magazine, a work carrier, means set in operation by said last named means for moving said work carrier to said chuck and then past said magazine, a ground workpiece being thereby removed from said chuck and discharged from the machine, and further means for moving said carrier past said magazine from the other direction, then to said chuck, and finally out of the proximity of said chuck, whereby a fresh workpiece is transferred to said chuck.

9. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, including means for causing a substantial separation between said instrumentality and chuck followed by a return motion to bring said parts together again'for further relative reciprocatory motion, of a magazine, a work carrier, means set in operation by said movement of separation for moving said work carrier to said chuck and then past )said magazine, a round workpiece being thereby discharged rom the machine, and for moving said carrier past said magazine from .the other direction, then to said a means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, includingmeans for causing a substantial separation between said instrumentality and chuck followed by a return to pick up an unground workpiece,

motion to bring said parts together again for further relative reciprocatory motion, of a work carrier, means set' in operation by said movement of separation for moving said work carrier to said chuck, for thereafter moving said work carrier to discharge a workpiece from said chuck, and further means set in operation by said movement for opening said chuck between said movements of the work carrier. f

11. The combination with a'grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, including means for causing a substantial separation between said instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, of a work carrier, means set in operation during said movementof separation for moving said work carrier to said chuck, for thereafter moving said work carrier to discharge a workpiece from said chuck, and further means for opening said chuck between said movements of the work carrier.

12. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, of means for determining when a workpiece has been ground to the desired size, a work carrler, means set in operation by said last named means for movlng said work carrier to said chuck, and means for thereafter moving said work carrier to discharge a workpiece from said chuck, and

further means for opening said chuck between said movements of the work carrier.

13. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, of means for determining when a workpiece has been ground to the desired size, a work-holding magazine, a work carrier, means set in operation by said last named means'for first moving said work carrier to said chuck and then past said magazine to remove a ground work piece and and for lastly moving sai carrier to said chuck, and

further means for opening said chuck after the first movement of the carrier and for closing said chuck on the unground workpiece after the third movement of. said carrier.

14, The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, including means for causing a substantial separation between said instrumentality and chuck followed by a.

return motion to bring said parts together again for further relative reciprocatory motion, of a work carrier, means set in operation by said movement of separation for moving said work carrier to said chuck, further means set in operation by said movement for opening said chuck, a magazine, means for moving said carrier to discharge the ground workpiece from said chuck, and means set in operation by the return movement between said chuck and grinding instrumentality for moving said work carrier by said magazine, picking up an unground workpiece and moving it to said chuck, and further means set in operation by said return movement for closing said chuck onsaid unground workpiece. v

15. The combination with a grinding instrumentality, a work-holding chuck, and means for causing a relative reciprocatory motion between said inding instrumen tality and said chuck, including means for causing a substantial separation between said instrumentality and chuck followed by a return motion to bring said parts together again for further relative reciprocatory motion, of a work carrier, means set in operation by said movement of separation for movin said work carrier into engagement with sai chuck, where it receives a ground workpiece from said chuck, and then away from said chuck, and for moving said carrier a second time into engagement with said chuck before the completion of the return movement between said chuck and grinding instrumentality, a magazine, and means for placing an unground workpiece from said magazine in the path ofsaid carrier.

16. The combination with a grinding instrumentality, a work-holding chuck, and

Ill

means for causing a relative reciprocatory motion between said grinding instrumentality and said chuck, of means for determiningwhen a workpiece has been ground to the desired size, a work carrier, means set III to said chuck, a magazine, and means for placing an unground workpiece from said magazme in the path of said carrier.

17. The combination with a grinding in-