US2581759A

US2581759A - Cam grinding machine

Info

Publication number: US2581759A
Application number: US153200A
Authority: US
Inventors: Clarence J Green
Original assignee: Norton Co
Current assignee: Saint Gobain Abrasives Inc
Priority date: 1950-03-31
Filing date: 1950-03-31
Publication date: 1952-01-08
Anticipated expiration: 1969-01-08

Description

C. J. GREEN CAM GRINDING MACHINE Jan. 8, 1952 7 Sheets-Sheet 1 Filed March -51, 1950 m/ ntor CLHEEVCE J. 6555M 5 QRMAQQL,

' fitte C. J. GREEN CAM GRINDING MACHINE Jan. 8, 1952 7 Sheets-Sheet 2 Filed March 51, 1950 Jan. 8, 1952 c. J. GREEN 2,531,759

v CAM GRINDING MACHINE 7 Filed March 31, 1950 7 Sheets-Sheet 3 Jan. 8', 1952 c. J. GREEN ,7

CAM GRINDING MACHINE Filed March 51, 1950 7 Sheets-Sheet 4 W F v 5 /a/ a4 Mum Jan.8, 1952 c. J. GREEN 2,581,759

CAM GRINDING MACHINE Fiied March 31, 1950 7 Sheet-Sheet 5 /00 /0@ I04 M5 I05 2 5 54 82 fizz/enter CMEEACE d. GEEEN 1952 c. J. GREEN 2,581,759

CAM GRINDING MACHINE Filed March 51. 1950 7 Sheets-Sheet e 57 M mum fifcorvey 1.952 c. J. GREEN 2,581,759

I CAM GRINDING MACHINE Filed March 51, 1950 I Y 7 Sheets-Sheet 7 fig/Z I Inventor 2 CLARENCE J GIPEE'N gy kmuPALo-wm Attorney Patented Jan. 8, 1952 CAM GRINDING MACHINE Clarence J. Green, Worcester, Mass., assignor to Norton Company, Worcester,

tion of Massachusetts Mass., at corpora- Application March 31, 1950, Serial No. 153,200

. 24 Claims.

The invention relates to grinding machines,

One object of the invention is to providea 4 simple and thoroughly practical automatic cam grinding machine to grind a plurality of cams which taper in opposite directions. Another'object of the invention is to provide an automatic grinding machine in which the cams on one end of the cam shaft may be ground to a predetermined taper in one direction and the remaining cams ground to a predetermined taper in the opposite direction. Another object of the invention is to provide an automatic cam grinding machine in which alternate pairs of cams may be ground to predetermined tapers in opposite directions.

A further object is to provide a wheel slide which is arranged to swivel in a horizontal plane and to provide a fluid motor which is arranged to position the wheel slide when in a central position for a grinding wheel truing operation, or to swivel the wheel slide in either direction to facilitate grinding predetermined tapers in opposite directions on the cams to be ground. Another ob ject of the invention is to provide an automatic control for swiveling the wheel slide which is actuated automatically by the longitutdinal movement of the taper to swivel the wheel slide into a central position for a grinding wheel truing operation or in either direction to facilitate grinding cams with surfaces tapered in opposite directions.

In the accompanying drawings 'in; which is shown one of various possible embodimentsflof the mechanical features of this invention}, Fig. 1 is a front elevation of the :improved automatic cam grinding machine; i

Fig. 2 is a plan View of the grinding machine; Fig. 3 is a vertical cross-sectional view, on an enlarged scale, taken approximately on'the line 3-3 of Fig. 1, showing the grinding'wheelfeed ing mechanism:

Fig. 4 is a diagrammatic view showing the mechanism for swivelling the wheel slide and the wheel slide base, together with a hydraulic piping and electrical wiring diagram of the controls therefor;

Fig. 5 is a diagrammatic view showing a modification of the mechanism for swivelling the wheel slide and wheel slide base, togethe'r'with'=a hy-' draulic piping and electric wiring diagram of the controls therefor; w

' cating mechanism;

Fig. 6 is a fragmentary rear elevation, on an enlarged scale, of the swivelling'motor and associated parts for swivelling the wheel slide and the wheel slide base;

Fig. '7 is a fragmentary plan view, on an em larged scale, of the swivelling motor and associated parts;

Fig. 8 is a fragmentary plan view, on an enlarged scale, partly in section, of the grinding wheel slide showing the wheel spindle recipro- Fig. 9 is a diagrammatic view showing the relative "positions of the grinding wheel, wheel spindle, and pivot for the wheel slide with the wheel in a central or truing position and also swivelled in opposite directions for grinding oppositetapers on the cams being ground; r

Fig. 10 is a fragmentary front elevation, on an enlarged scale, showing the gauge plug for locating the grinding wheel laterally relative to the pivot for the wheel slide base;

Fig. 11 is a fragmentary side elevation, on an enlarged scale, showing the location of the gauge plug for setting up the grinding wheel relative to the pivot for the wheel slide base; and

Fig. 12 is a diagrammatic view substantially identical to Fig. 5 excepting that it shows a numberof additional table dogs.

An automatic cam grinding machine has been illustrated in the drawings comprising a base It] which supports a longitudinally movable worktable I I on the usual fiatway I2 and V-way I3 formed on the upper surface of the base Ill.

The base Ill also supports a transversely movable wheel slide I5 which is arranged to slide 1 transversely on a V-way I6 and a fiatway l1 formed on the upper; surface of a wheel slide base I8. The wheel slide I5 is provided with a rotatable wheel spindle. I9 which supports a ro-, tatable grinding wheel 20. The grinding wheel 29 may be driven by meansof an electric motor 2i which is mounted on the upper surface of the wheel slide I5. The motor 2| is connected by a V-belt drive (not shown) contained within a guard 22 (Figs. 1 and 2).

The worktable I I serves as a support for a pivotally mounted rock bar 25 which is pivotally supported in bearing brackets (not shown) fix-,

edly mounted on the upper surface of the table II. The rock bar 25 serves as a support for a master cam spindle 26 which extends within a headstock housing 21. The master cam spindle Z5 is provided with a cam shaft supported center 28 for supporting the left-hand end of a cam shaft 29 to be ground. The rock bar 25 also supports a footstock 30 having a footstock center 3| for supporting the right-hand end of the cam shaft 29.

The master cam spindle 26 may be driven by an electric motor 35 mounted on the upper surface of the headstock housing 21. The motor 35 is drivingly connected in a manner (not shown) positively to rotate the master cam spindle 26 and the cam 29 to be ground. The master cam spindle 26 is provided with a plurality of master cams 32 which are arranged to be successively engaged by a master cam roller 33 for controlling the rocking movement of the rock bar 25 so as to generate a predetermined contour on the cam being ground. This mechanism as a part of the present invention may take any suitable form and therefore has not been illustrated in detail. The drive for the master cam spindle 23 and the arrangement of the master cams and follower roller may lee-identical with that shown in the prior 1L s. Patent No. 2,185,837 to G Crompton, Jr-.,- dated January 2, 194:0, to which reference may be had for details of disclosure not contained herein. 7

A-suitable wheel feeding mechanism is provided for feeding the grinding wheel slide l transversely relative to-the wheel slide base it. This mechanism is preferably arranged so that the wheel'slide may be readily fed toward or from the work piece regardless of the position of the wheel slide case As illustrated in the drawings a rotatable'feed screw Ali is supported in anti-,iriction bearings 4i anddg which are in turn xe y s p i iv it n ed re ine h n plrgjected from-the lowersur-face of the wheel slide base 18. The grinding wheel slide ltis provided with a dependin half nut which projects downwardly from the underside of the wheel slide and meshes with the feed screw 40. The forward end of the feed screw 40 is connected by means oi -a. universal joint 45 with a rotatable sleeve 45. A shaft 4! is slidably keyed within a central aperture within the sleeve 46. The shaft 4? is connected by means of a universal joint 48 with a rotatable shaft 49 journalling in anti-friction bearings 59 and 5| which are fixedly supported relative to thebase lili A gear 52 mounted on. the left-hand end of the shaft. 49 (Fig. 3) meshes with agear 53 which is rotated by the manually operable feed wheel 54. It will be readily apparent from the foregoing disclosure that rotation of the. feed wheel 54 will betrans mitted through the mechanism above described to-rotate the feed screw (30 so as toimpart a transverse. feeding movement of the wheel slide i5 either toward. or from thecam shaftv 29 being round. A micrometer wheel feed adjustin mechalfiis'm 55,. which may be of the standard well ignownvariety such as for example that shown n the expired U 3., patent to C. H. Norton, No. 762,838, 'dated June 14, 190.4, to which reference may be had for details of disclosure not contained herein. This micrometer adjusting mechanism 55 serves to facilitate precisely adjustin a stop ahutment (not shown) relative to a pivotally mounted'stop pawl 55 which is pivotally mounted on the front of the. machine base it. Due to theuniversal joints 45 and 43 together with-the telescopic shaft 4'! within the sleeve 43, a feeding o m n may be transmitted to the feed screw regardless of whether the wheel slide baseuis in a central'or truing position or is swiveled-in either direction for grinding a tapered surface onthecambeingground. 7' I v V A suitable mechanism is provided $01 We??? tation of the traverse wheel to will move the table II lon itudinally in either direction depending upon the' vdirection of rotation of the handwheel 63.

In order to operate the machine automatically the table H may be moved longitudinally by means of a hydraulic mechanism comprising cylinder 63 which contains a slidably mounted piston 64. The piston 64 is connected to the lefthand end of a piston rod 65 (Fig' 4). The rights hand end of the piston rod 55 is connected to bracket fifiwhich is fixedly mounted on the work table II. It will be readily apparent that as fluid under pressure is passed through a pipe 5? into a cylinder chamber 55, the piston 5A together with table H will be moved toward the right. During this movement, fluid within a cylinder chamber 69 may exhaust through a pipe is. Similarlyas fluid under pressure is admitted through the pipeJQ into the cylinder chamber 63, the piston 64 together with the table ilwill be moved toward the 'leit. o

A suitable automatic control mechanism for controlling the admission of fluid to the cylinder 63 maybe provided for automatically indexing the table successively to position cams on the cam shaft 29 into operative relationship with the grinding wheel as. This mechanism as a part of the present invention may take any suitable form, and consequently hasnot been illustrated in de* tail. This mechanism may be substantially iden-- tical with that shown in the prior U. S. Patent No. 2,185,837, above referred to, to which reference may be had for details of disclosure not contained herein.

A grinding wheel truing tool or diamond 15 (Fig. 4) is adjustably mounted on the rock bar 25 and is arranged so that when the table 1 l is traversed to an extreme left-hand end position beyond the last cam on the right-hand end of the cam shaft 29, the diamond or truing tool 15 will be passed across the peripheral face of the grinding wheel 2b to true the same. I Inthe grinding of automotive cam shafts in accordance'with the present vpractice in many automotive shops, it is desirable to not only pro-. vide a cam having a predetermined contour but also tapering from side to side so that when installed in the automotive engine, rotation of the cam on the valvetappet will cause a rotary motion to be imparted to the tappet. In some 21111309 motive engine designs it is necessary due to the arrangement of valves and tappets to provide cams having peripheral surfaces tapering in cpposite directions. In some cases it is desirable to provide a taper toward the left on all of the cams on the left-hand end of the cam shaft 2%, as shown in Fig. 4, and to provide a taper toward the right on the remainder of the cams on the right-hand end of the shaft 29. In order to accomplishthis desired result a swivelling mochanism, such-as for exa ple a hydraulically operated mechanism is provided for swivelling the wheel slide base in a horizontal plane from a central or truing position in one direction to producethe required taper on part of the cams on the shaft 29 after which the wheel slide base is swiveled into the opposite extreme position for producing a predetermined taper on the remain.- er of the cams in an opposite direction. This mechanism may comprise a hydraulic cylinder 89 which is fixedly mounted on the base I0. cylinder 80 contains a slidably mounted piston 8| (Figs. 4 and 6). The piston 8| is connected to one end of a piston rod 82. The other end of the piston rod 82 passes through a clearance hole 83 in a bracket 84 which is fixedly mounted on the underside of the wheel slide base I8. The piston rod 82 is held in a fixed positionrelative to the bracket 84 by means of a nut 85 screw threaded on the left-hand end of the piston rod 82. The wheel slide base I8 is connected by means of a vertically arranged stud 86 with the base I; As shown in Figs. 2 and 4 axis of the pivot stud 86 is located directly under the center of the grinding wheel 20 in a vertical plane midway between the side faces of the grinding wheel and normal to the axis of the wheel spindle, so as to facilitate swivelling the wheel slide base I 8 a'predetermined amount in either direction '-to facilitate grinding tapers of the same degree in op- .posite directions on predetermined cams on the cam shaft 29 regardless of the diameter of the grinding wheel. It will be readily apparent that when fluid under pressure is passed through a pipe 8! into a cylinder chamber 88, at the righthand end of the cylinder 80, the piston 8| will be moved toward the left (Fig. 4) to swivel the wheel slide base I8 and the wheel slide I5 in a counter-clockwise direction into the position illustrated in Fig. 4. During this movement fluid within a cylinder chamber 89 at the left-hand end of the cylinder 80 may exhaust through a pipe 90.

Similarly when fluid under pressure is admitted into the pipe 90 into the cylinder chamber 89, the piston 8| will be moved toward the right (Fig. 4) to swivel the wheel slide base I8 and the grinding wheel slide I5 in a clockwise direction into the dotted line position I8a as shown in Fig. 4. This swivelling movement of the wheel slide base I8 and the grinding wheel I5 serves to position the grinding wheel for grinding a predetermined taper toward the right on the cams located on the right-hand half of the cam shaft 29.

It is desirable to provide means for truing a true cylindrical surface on the periphery of the grinding wheel. This is preferably accomplished by positioning the wheel slide base I8 and the wheel slide I5 in a central position with the axis of the grinding wheel spindle parallel with the axis of the cam shaft 29 being ground. In order to automatically locate the wheel slide base in a central position a hydraulically operated mechanism is provided comprising a cylinder 95 which contains a slidably mounted piston 96. The piston 96 is provided with an integralpiston rod 91 having a tapered end portion 98'which is arranged to mate with a'V-shape notch 99 formed in a plate I00 fastened to the rear end of the wheel slide base I8. A compression spring IOI surrounds the piston rod 91 and is interposed between the piston 96 and an end cap I92 at the lower end of the cylinder 95 (Fig. 4) The spring I0| serves normally to maintain the piston 95 in an uppermost position (Fig. 4) so that the tapered portion 98 of the piston rod is in an inoperative position. When it is desired to true The amine the grinding wheel, fluid under pressure may be admitted into a pipe 7 I03 into the upper end of the cylinder 95 to cause a downward movement of the piston 96. At the same time fluid under pressure is passed through the pipe to swivel the wheel slide base I8 in a clockwise direction. This clockwise swivelling movement of the wheel slide base I8 continues until the tapered end portion 98 engages the notch 99 which serves to lock the wheel slide base I8 and the wheel slide I5 in a central or truing position.

The actual amount of swivel of the wheel slide base I8 and the grinding wheel slide I5 is veryslight being only suflicient to produce tapered surfaces on the work piece amounting to a fraction of one degree. In the average case the amount of taper used is from five to twenty-five minutes. As shown in the diagram the amount of taper both on the cams being ground and the swivel of the wheel slide base .I8 and the wheel.

slide I5 has been somewhat exaggerated so as to clarify the operation of the machine. A pair of opposed stop screws I04 and I05 (Figs. 6 and 7) are provided for limiting the swivelling movement of the wheel slide base I8 in opposite directions. The stop screws I04 and I05 are screw threaded into lugs I 00 and I0! respectively which are fixedly mounted relative to the base I0. Stop stud I08 projects downwardly from the wheel slide base I8 and is arranged in the path of the stop screws I04 and I05. A pair of lock nuts I09 and II 0 are provided for locking the stop screws I04 and I05 respectively inadjusted positions. 7 1

A suitable hydraulic control mechanism is provided for controlling the admission to and exhaust of fluid from the

cylinders

80 and 95. This mechanism may comprise a solenoid actuated control valve 2. This valve is a piston type valve having a valve stem H3. The valve stem I I3 is normally held in a right-hand end position, as illustrated in Fig. 4, by, means of a compression spring I I4 contained within the left-hand end of the valve II 2. An electric solenoid H5 is provided for shifting the valve stem H3 in a direction toward the left (Fig. 4). In the position of the valve II2 (Fig. 4) fluid under pressure from a suitable source of supply such as for example a fluid pump (not shown) contained within the grinding machine base I0 forces fluid under pres sure through the pipe I I6 to the valve II 2. In

pressure passing through the pipe II5,'passes through the valve I I2 and out through a pipe I I? to other mechanisms of the machine. In this position of the valve II2 fluid within a cylinder chamber II8 in the cylinder may exhaust. through the pipe I03 into the valve I 52. The exhaust fluid entering the valve I I2 passes through a central aperture H9 and out through an exhaust pipe I20. When the solenoid H5 is energized, the valve stem II 3 is moved toward the left so that fluid under pressure in the pipe II6 passes through the valve |I2 into the pipe 503; into the valve chamber M8 to cause the piston 96 to move downwardly (Fig. 4), to shift the tapered end 98 of the piston rod 91 into operative engagement with the block I00 so that when the wheel slide base swivels into a central position the tapered portion 98 will drop into the notch 99 to locate the wheel slide base I8 and the grinding wheel'slide I5 in a central position for a grinding wheel truing operation with the axis of the grinding wheel spindle arranged parallel with the table II andcam shaftzs. i.;.

A-iiuid pressure actuated ontrol valve Ida is presided for contr lling the admission to and X, haust of fluid-from the swivel m tor or cyl nd 89. This valve is a piston type valve having a slidably mounted valve member I26 which is'shifted longitudinally within the valve casing when fluid under pressure is passed into end chambers 52? or I28. In order to control the movement of the valve piston I25, a solenoid actuated pilot valve I29 is provided comprising a valve stem I38 which is fastened to one end of a slidably mounted valve member 43!. A compression spring I32 normally holds the valve memberv I3I in-a right-hand end position (Fig. a). An electric solenoid I33 is provided which when energized serves to shift the valve member I 3I into a left-hand end po: sition. As shown in the drawings fluid under pressure from the source passing through the pipe I45 passes through-the pilot valve 12%. through a passage 34 into the end chamber 2 3 to move and hold the valve member I26 in a. lett hand end position. In this position of the valve I28 fluid under pressure in the pipe I55. passes through a chamber I35 in the'valve mem her I Zeand passes out through the pipe 8'! intothe cylinder chamber '38 to move the piston 8i toward the left (Fig. 4) into its left-hand end position so as to swivel the wheel slide base I8 and grinding-wheel slide I5 in a counter clockwise direction into position illustrated in Fig. .4. When thesolenoid I33 is energized to shift the valve. member I3I toward the left, fluid under pressure within the pipe H6 passes through the pilot valve member I3'I, through a passage I35 into the chamber I121 to move the valve member. 25 to ward the right. When the valve member I26 is in its right-hand end position fluid under pressure in the pipe IIB passes through the valve chamber I35 and out through a. pipe I31, through cylinder chamber formed at the lower end of the cylinder 95 (Fig. 4). Fluid then passes through the pipe BI) into the cylinder chamber .89 to move the piston 8| toward the right. Fig 4) which serves to swivel the wheel slide base is in a clockwisedirection into' the dotted line position I8a. This movement serves also to shift the wheel slide I5 also in a clockwise direction so as to position the grinding wheel 2|! for grinding a taper in the opposite direction on the cams on a last cam on the left-hand end of the cam. shaft 29 has been ground, the table II traversesv idly' in a direction toward the left toreturn the parts of the machine to the initial position. As the table approaches a left-hand end position, a dog I40 depresses a plunger IM to close a pair of normally open limit switches LS9 and LSIB'. The closing of the limit switch LS9 closes acircult to energize the solenoid I I5 to shift, the valve stem I I3 toward the left so that fluid under pressure in the pipe I I6 passes through the valve I.I2.. through the pipe I83 into the cylinder chamber H8 to move the piston 96 downwardly (Fig. 9) so that the tapered end 98 of the piston rod 9'! engages the plate I00. At the same time, the closing. of the limit switch LSII] serves to energize a relay switch I43 which closes a circuit to energize the solenoid I33. Energizing thesolenoid I33 serves to shift the pilot valve stem I38 toward the left so that fluid under pressure in the pipe II6 passes through the pilot Valve I 9.

through the passage I36 into the valve chamber piston 8I to move toward the right thus swivel- 7 ing the wheel slide base I8 and grinding wheel slide I5 in a clockwise direction until the tapered end 98 slides into engagement with the notch 99. The notch 99 serves to locate the wheel slide base I8 and grinding wheel. slide I5 in a central or truing position with .the wheel spindle I9 arranged parallel to the cam shaft 29 and the table I I. Downward movement of the piston 96, closes the port at the end of the pipe I31 so as to cutoff fluid under pressure from'the pipe 99 thereby relieving pressure on the piston 81 during the truing operation while the tapered end 98 of the rod 9'! is in engagement with thenotch 99. Continued movement of the table II toward the left passes the truing tool I5 across the periphery of the grinding wheel 20 after which the table II reverses and the tool '55 makes a second pass across the Wheel to true a cylindrical face thereon after which the table stops in a loading position Movement of the table Ii toward the right into a loading position, moves the dog Hill on the plunger I II, the plunger MI moves upwardly under the influence of the spring I42, so as to open the limit switches LS9 and LSIil. The opening of the limit switch LS9 deenergizes the solenoid I I 5 so that the released compression of the spring I I4 shifts the valve member I I3 toward the right into the position illustrated in Fig. 4. In this position of the valve II2 fluid within the cylinder chamber II8 may exhaust through the pipe )3, through a central passage in the valve member and exhausts through the "pipe i2 5}. The opening of the limit switch LSIB does not effect the solenoid I33, since a holding circuit in the relay switch I43 holds the relayswitch closed so that after the pressure has been relieved from the cylinder' chamber I I8, the release compression of the spring IIlI moves the piston upwardly and allows fluid under pressure passing through the pipe .90 to continue the movement of the piston 8! toward the right to impart a further swivel ling movement of'the wheel slide base is and the wheel slide I5 in aclockwise direction to position the wheel slide base in the dotted. line position IBa forthe start of the next grinding operation.

As Shown diagrammatically in Fig. 9, the grind ing Wheel 20 is shown in a truing position. The swivelling movement of the wheel slide base It and. griding wheel slide I5 in a clockwise direction, shifts the wheel spindle i9 and grinding wheel 20 into broken line positions I92) and 202? (Fig. 9). This movementserves to position the grinding wheel for grinding a tapered surface on the cams located on the right-hand end of the cam shaft 29, the surfaces of the cams being tapered in a direction toward the right. When the table II has been successively indexed to the. central portion of the cam shaft 29, in its movement toward the right, the dog I44 engages and actuates the limit switch LSI I to open the holding circuit of the relay I43 so as to deenergize the switch I43. This actuation of the relay switch I43 deenergizes the solenoid I33 thus releasing the compression of the spring I32 which returns the valve member I3I in a direction toward the right into the position illustrated in Fig. 4. When the valve member I3I reaches its right-hand end position fluid under pressure may pass into the valve chamber I28 to move the valve member I26 toward the left so that fluid under pressure within the pipe I I6 may pass through the valve chamber I35, through the pipe 81 into the cylinder chamber 88 to move the piston 8| toward the left thus swivelling the wheel slide base I8 and the grinding wheel slide I in a counter-clockwise direction into the position illustrated in Fig. 4. The wheel spindle I9 and grinding wheel 20 are thus shifted from positions I91) and 2612 (Fig. 9) into positions I9a and 20a so that the grinding wheel 20 will be positioned for grinding a taper in the opposite direction on the remainder of the cams on the cam shaft 29 as the table II is intermittently indexed toward the right. It will thus be seen that as shown in Figs. 4 and 9 cams tapering in the opposite direction may be ground on opposite ends of the cam shaft 29.

It may be desirable to grind alternate adjacent pairs of cams on the cam shaft 29 tapering in opposite directions as shown diagrammatically in Fig. 5. In the modification shown in Fig. 5, a pipe I50 serves to supply fluid under pressure to a solenoid actuated valve I5! having a valve stem I52 connected with a valve member I53. A compression spring I54 serves normally to maintain the valve member I53 in a right-hand end position. A solenoid SI is provided for shifting thevalve stem I52 and the valve member I53 toward the left. When-the solenoid SI is energized, fluid under pressure within the pipe I59 may pass through the valve I5I and through a pipe I55 into the cylinder chamber IIB to cause the piston 96 to move downwardly (Fig. 5) so that the piston rod 91 moves into the path of a stop surface I58 formed on the plate I00. During this movement, fluid may exhaust from the valve I5I through a pipe I56.

A fluid actuated control valve I60 is provided for controlling the admission of fluid under pressure to the cylinder. 80.. The valve I60 is provided with a slidably mounted valve member I6I and end chambers I62 and I63. A pilot valve I64 is provided for controlling the shifting movement of the valve member I6I. The pilot valve I64 comprises a valve stem I65 which is fixedly connected to a valve member I66. In the position of the valve I64 (Fig. 5) fluid under pressure in the pipe I50 passes through a passage I61 into the end chamber I63 to shift the valve member I6I toward the left so that fluid under pressure within the pipe I56 may pass through a valve chamber I83, through a pipe I68 into a cylinder chamber 88 to move the piston 8| toward the left thereby causing a counter-clockwise swivelling movement of the wheel slide base I8 and the grinding wheel slide I5 into the position illustrated in Fig. 5. During movement of the valve member I6I toward the left (Fig. 5), fluid within the end chamber I62 may exhaust'through a passage I69 and through the pilot valve I64. The valve stem I65 is arranged to be shifted longitudinally by a pair of solenoids S2 and S3. As illustrated in Fig. 5 solenoid S2 is energized to position the valve member I66 in its right-hand end position.

The valve I60 also serves to control the admission of fluid to a fluid actuated control valve I10. The valve I comprises a slidably mounted valve member HI and end chambers I12 and I13. A pilot valve I14 is provided for controlling the shifting movement of the valve member I1 I The pilot valve I14 comprises a valve stem I which is fastened to a valve member I16; A compression 10 spring I11 serves normally to hold the valve member I16 in a right-hand end position. A solenoid S4 is provided for shifting the valve stem I15 and the valve member I16 toward the left. In the position shown in Fig. 5, fluid under pres+ sure in the pipe I50 may pass through the pilot valve I14, through a passage I18 into the end chamber I12 to shift the valve member I14 toward the left into the position as illustrated in Fig. 5. During this movement of the valve member I1I, fluid within the end chamber I13 may exhaust through a passage I79 and out through the pilot valve I16. A pipe I82 connects the valve I10 with the valve I60. When the valve member I5I is shifted into its right-hand end position, fluid under pressure in the pipe I50 may pass through the valve chamber I83, through the pipe I82 into the valve chamber I8I in the valve I10. In the position of the valve I10 as shown in Fig. 5, fluid under pressure entering the valve chamber I8I may pass through the pipe I into the cylinder chamber 89 to cause the piston 8| to move toward the right. 'When the valve member I1I is moved into'the right-hand end position by energization of the solenoid S4, fluid under pressure within the valve chamber I8I may pass through the pipe I84 into the cylinder chamber I02formed at the lower end of the cylinder 95 so as to cause an upward movement of the piston 96 to move the piston rod 91 upwardly into an inoperative position.

To facilitate automatically controlling the valves I5I, I60 and I10, a plurality of limit switches actuated by dogs adjustably mounted on the front edge of the table II are provided. An adjustable table dog I is provided for actuating a vertically movable plunger I9 I against the compression of a spring I92. A downward movement of the plunger I9I as caused by the dog I80 serves to close the normally open limit switches LS9 and LSIII. A normally open limit switch I95 is arranged to be actuated by a pair of spaced adjustable dogs I96 and I91 when the table is moved toward the right. A normally open limit switch I98 is arranged to be closed by an adjustable dog I99 when the table II is moved toward the right. Similarly a normally open limit switch 200 is arranged to.be actuated by an adjustable dog 20I when the table II is moved toward the right.

The operation of the modified construction shown in Fig. 5 is somewhat similar to that shown in Fig. 4 except that the wheel slide I5 and wheel slide base I8 are swivelled after each pair of cams have been ground .so that tapered surfaces tapering in the opposite direction are produced on adjacent pairs of cams. The table dogs I96, I91, I99 and 20I are arranged so that during the movement of .the table I I toward the left the dogs ride idly over the respective limit switches. As shown in Fig. 5 the table II indexes toward the right to grind the last cam on the left-hand end of the cam shaft 29 after which the grinding wheel slide retreats and the table II moves through an idle stroke toward the left. As the grinding wheel 20 approaches the truing tool 15, the dog I90 engages and depresses the plunger I 9| to close the limit switches LS9 and LSIII. The closing of the limit switch LS9 serves to energize the solenoid SI to shift the valve I5I so that fluid under pressure from the pipe I50 passes through the valve I5I and through the pipe I55 into the cylinder chamber IIO to cause a downward movement of the piston 96 thereby moving r if i the piston rodST into the patriotsstop surface I58 formed on the plate I 08; At the same time closing of the limit switch LSI energizes the sole--' noid S3 to shift the valve member lfili' to-ward the left thereby shifting the valve member IE toward the right so that fluid under pressurefrom I83, through the pipe I82 into the valve chamber I'8 I of the valve I'IU. Fluid under pressure'enter ing the valve chambei 18! passes out throughthe drical surface thereon. During this movement the wheel spindle I9 is arranged parallel with the cam shaft 29 and the table II. After one complete reciprocation of the 'truing tool acrossthe face of the grindingwheelrthe machine stops and the groundcam shaft may be removed from the machine and replaced with a new cam shaft to be ground; Q I

In this position. the tableI I has moved a sumcient distance toward the left so that the dog 2% is at the left of the limit switch 29f When the next grinding cycle is started the table starts moving'toward the right to position the first'ca'm in an operative position relative to the grinding wheelZil. Duringthis positioning movement the dog'ZEI closes the limit switch 289 to energize the solenoid S d thereby shifting the pilot valve I14 to move the valve member HI toward the right so that fluid under pressure will pass from the through the pipe I80 into the cylinder chamber 89, so that'as'soon as the piston: rod 91 withdraws from engagement with the stop surface I58, the pressure within the cylinder chamber 89' will-cause a further clockwise .swivelling of the wheel slide base I8 and grinding wheel slide it to position the grinding wheel 29- in position 29b (Fig. 9) for grinding the first pair of'cams on the cam shaft 29. After the first two cams on the right-hand end of the cam shaft have been ground and the table II starts the next indexing movement toward the right. the dos I91 engages and closes the limit switch I95 to energize the solenoid S2 thereby shifting the pilot valve I64 into the position illustrated in Fig. so that fluid under pressure entering the valve chamber I83 will pass through the pipe I68 into the cylinder chamber 88 to move the piston BI toward the left thereby causing a counter-clockwise swivelling of the wheel slide base I8 and grinding wheel slide I5 to position the grinding wheel 20 in position 28a (Fig.9) while grinding the third and fourth cams on the camshaft 29. After the third and fourth cams have been ground and the table II starts its indexing movement toward the right, the dog I98'1engages and closes the limit switch I98 which serves to energize the solenoid S3 to shift the pilotvalve I64 toward the left-and the valve the pipe I58 passes through the valve chamber Y 12 member for toward the} right so that fiuid nder pressure within the valve chamber I83; will pass through the pipe I82 into the valve'chamber Id? of the valve I10 and through the pipe Ito into the cylinder chamber 89 so as to move'the pis ton BI toward the right thereby swivelling the wheel slide base I8 and grinding wheel slide i5 in a clockwise direction to position the grind ing wheel 20 in position 2% (Fig. 9) while grind ing the fifth and sixth cams on the cam shaft 29. During the next indexing movement of the table toward the right,- the dog I98 engages and closes the limit switch I95 so as to again energize the solenoid S2 and thereby to cause a swivelling movement ofthe wheel slide base it and wheel slide I5 to position the grinding wheel 29 in position 20a (Fig.4?) while grinding the seventh and eighth cams on'the cam shaft;

The above described modification facilitates grinding tapers on successive pairs of cams tapering in the opposite direction. By the provision of additional table dogs, if desired, the grinding wheel may be readily swivelled after each cam has been ground to tapered surfaces which taper in opposite directions, such addi tional dogs are shown in Fig. 12', being indicated by the reference characters I96a, 19cc, mm, and I991).

It is desirable to provide a wheel spindle rcciprocating mechanism for reciprocating the grinding wheel spindle I9 axially within its bearings during a grinding operation. This mechanism may comprise a worm 2) (Fig. 8) mounted on the wheel spindle I9. The worm 2H} meshes with a worm gear 2 mounted on a vertical shaft 2I2. The vertical shaft 2I2 is provided at its upper endwith an eccentric stud 2I3 which supports an eccentric disc 2M. The eccentric disc 2H is surrounded by one part of a connecting rod 2I5. The connecting rod is preferably made in two parts to facilitate adjustment as will be hereinafter described. An adjustable part 2I6 of the connecting rod 2%5'is provided with a yoked .end 2I'I which engages a stud 229 carried by a pivotally mounted yoked member 2I8. The yoked member 2I8 is pivotally mounted on a stud 2I9 which is fixed relative to the wheel slide I5; A tension spring 22! is connected between a stud 222' on the yoked member 2'I3 and a stud 223 fixedly mounted within the wheel slide It; The spring 22I serves normally to maintain the stud 228 positioned within the yoke ZI'I. It will be readily appar ent from the foregoing. disclosure that rotation of the wheel spindle I9 will be imparted through the worm 2H), the worm gear 2, the shaft 2I2,

the eccentric stud 2I3, the eccentric disc 2! to oscillate the connecting rod ZI5 which serves to impart an oscillating movement to the yoked member 2I8- thereby reciprocating the wheel spindle I9 axially within its bearings. The yoked member 2I8 is provided with opposed studs (not shown) which engage a groove (not shown) formed on the wheel spindle I9.

As above explained, the pivot for the wheel slide base I8 is located with its axis in a central plane of the grinding wheel normal to the axis of the grinding wheel spindle in order to facilitate swivellingr the wheel slide base !8 and grinding wheel slide I5: in either direction to grind oppositely tapered surfaces on the cams being ground. When the grinding wheel reciprocating mechanism is employed for a grind ing operation, it is desirable that thereciproc'as tion whioh maybe or the order or to: of

13 an inch, be arranged so that the grinding wheel 20 reciprocates an equal amount in opposite directions relative to the axis of the pivot stud 86. In order to accomplish this result, an adjustment is provided to vary the length of the connecting rod H5. The adjustable part of the connecting rod 2| 6 is provided with an elongated slot 224. A clamping screw 225-passes through the slot 224.. and is screw threaded into the connectin rod Hi). In order to facilitate precise adjustment of the connecting rod part 216, a pull-screw 226 passes through a clearance hole in the part 216 and is screw threaded into the connecting rod 2| 5. A push-screw 221 is screw threaded through a portion of the part 2l6 and bears against a portion of the piston rod 2l5. It will be readily apparent from the foregoing disclosure that by "loosening the clamping screw 225. and manipulating the ad-

J'usting screws

226 and 221, the effective length of the piston rod: 2l52l5 may be varied if desired.

In order to facilitate setting up the wheel spindle reciprocating mechanism and thereby locating the grinding wheel relative to the pivotal axis of the stud 86, a gauge plug 230 is mounted on the wheel slide base 18. The gauge plug 23 i is located directly below a portion of the grinding wheel 26, so that by means of measuring instruments the grinding wheel may be centered relative to the plug 230 which also centers the wheel relative to the pivotal axis of the pivot stud 86. In order to set up the reciprocating mechanism so that the reciprocatory stroke of the grinding wheel is centered relative to the axis of the pivot stud86. The eccentric stud 213 and the eccentric disc 2l4 are positioned in a mean position as illustrated in Fig. 8. While the eccentrics are positioned in this position, the length of the connecting rod 2l5-2l6 is adjusted by manipulation of the clamping screw 225 and the adjusting screws-226 and 221 so that the grinding wheel 20 will be centered laterally relative to the gauge plug 230. After this adjustment has been made, the clamping screw225 H may be again tightened to lock-the part 216 in adjusted position relative to the connecting rod 215. It will be readily apparent from the foregoing disclosure that adjustment of the length of the connecting rod 2l52lli serves to. adjust the position of the yoke 2l8 and thereby to adjust the position of the wheel spindle l9 axially within its bearings. With the adjustment made in the above mentioned position of the parts, a reciprocatory stroke of the grinding wheel will be obtainedwhich will be precisely centered relative to the axis of the pivot stud 85 so that equal tapers, in the opposite direction may be produced on successive cams onthe cam shaft 29.

The operation of the improved automatic cam grinding machinewill be readily apparent from the foregoing disclosure. The machine stops in a loading position with the table ll positioned so that the grinding wheel'20 is opposite the right-hand end'of the cam shaft 29. Th'e'cycle erative position for grinding. During this shift- .ingmovement of the table, the-wheel slide base 1'4 l8-and the grinding wheel slide 15 are swiveled in a clockwise direction to position the grinding wheel for grinding a predetermined tapered surface on thecam. After the first cam has been ground the table II is again indexed and successive cams are! ground to the desired and predetermined taper. As shown in Fig. 4 the machine is arranged for grinding the cams on the righthand end of the shaft tapering toward the right. After all of these cams have been ground, on the next table indexing movement the swivelling mechanism is actuated to shift the wheel slide base It and grinding wheel slide! 5 in a counterclockwise direction into position 20a (Fig. '9) for grinding the remaining cams on the cam shaft; In the modification shown in Fig. 5 the the grinding wheel, the wheel slide base swivelling mechanism operates to swivel the wheel slide base l8 and grinding wheel slide I5 to a central or truing position to locate the wheel spindle l9 parallel with the longitudinal movement of the table II for a grinding wheel truing operation. After the table traverses the diamond across the face of the grinding wheel and returns, the table II stops in a loading position after which the ground shaft maybe removed from the machine and a new shaft to be'ground inserted there instead.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above in vention and as many changes might be made in the embodiments above set forth, it is to .be understood that all matter hereinbefore'set forth or shown in the accompanying drawings is to be interpretedas illustrative and not in a limiting sense.

I claim: I

1. In a grinding machine having a transversely movable wheel head, a rotatable grinding wheel thereon, a pivotal mounting for the head, means to feed said head transversely, a longitudinally movable work table having a rotatable work support thereon, means for moving the table longitudinally successively to position spaced portions of a work piece relative to the grinding wheel, a fluid motor to swivel said head in either direction, and means including a control valve mechanism actuated by and in timed relation with said table movement to control the swivel motor so asto swivel said head in one direction to facilitate grindinga predetermined taperin one direction on part of the portions to be ground and to swivel said head in the opposite direction to facilitate grinding a predetermined taper in the opposite direction on the remainder of the 3; In a grinding machine, as claimed in claim 1, in combination with the. parts and features for actuating said control valves automatically to control the swivelling movement of the wheel head in'either direction and to locate the wheel head in a central position in timed relation with the longitudinal movement of the table.

4, In a cam grinding machine having a base,

,a transversely'movable wheel head, a rotatable grinding wheel. thereon, aplvotal mounting for he he d,means to feed said head transversely, a'longitudinally movable table, a. rotatable cam shaft sup-port thereon, means for moving the table longitudinally successively to position spaced cams in operative relation to the grinding wheel, a piston and cylinder to swivel said head in either direction, adjustable stops to limit the swivelling movement of the head in either direction, and means including a control valve mechanism actuated by and in timed relation with the table movement to control the piston and cylinder so as to alternately swivel said head i opposite directions after each cam has been ground to facilitate grinding a predetermined taper in opposite directions be. ground. I V

5. In a cam grinding; machine having a base, a transversely movable wheel head, a rotatable on alternate cams to gr nding wheel thereon, a pivotal mounting for the head, means to feed saidhead, transversely, a longitudinally movable table, a rotatablecam shaft support thereon, means for moving the table longitudinally successively to position spaced cams in operative relation to the grinding wheel, a piston and cylinder to swivel said head in either direction, adjustable stops to limit the swivelling movement of the head in either direction, and means including a control valve mechanism actuated by and in timed relation with the table movement to. control the piston and cylinder so as to alternately swivel said head in oppo's'ite directions after each pair of cams has been ground to facilitate grinding a predetermined taper in. opposite directions on alternate pairs of cams to be ground.

, 6. In a cam grinding machine having a base, a transversely movable wheel head. a rotatable grinding wheel thereon, a pivotal mount for said wheel head, means to feedsaid head transversely, a longitudinally movable work table having a rotatable cam shaft support thereon, means for moving the table longitudinally successively to position successive cams in operative relation with the grinding wheel, a fluid motor to swivel said head in either direction, adjustable stops to limit the swivelling movement of 'the head in either direction, and means including a control valve mechanism automatically actuated by and in timed relation with'the longitudinal movement of .the table to control the swivel motor so as to swivel .the head one direction to facilitate be ground.

7. In a grinding machine having a transversely movable wheel head, a swivellingsupport for said wheelzhead, Ia, fluid motor to swivel said head, means including a control valveior controlling said fluid motor'so as: to swivel the. head in either direction for grinding tapers in opposite directions on a work piece, and means including a locating pawl for locating the wheel head in a central position for a grinding wheel truing operation.

8. In a grinding machine having a base, a transversely movablev wheel head having a rotatable grinding wheel thereon, a pivotal mounting for the wheel head, a longitudinally movable table having a rotatable work support thereon. means for moving the table longitudinally to osition a work piece relative to the grinding wheel. a: fluid motor to swivel said head in either direction to facilitate grinding tapers in opposite directions on spaced portions of the work piece, means including an index pawl to facilitate locating thev wheel head in a central position for a truing operation, and means including a piston and cylinder actuated by and in timed relation with the longitudinal movement of the table to control the movement of said pawl.

9. In a grinding machine having a base, a transversely movable wheel head, a rotatable grinding wheel thereon, a. pivotal mounting for the wheel head, means to feed said head transverse1y,.a longitudinally movable work table having a rotatable work support thereon, means for moving the table longitudinally successively to position spaced portions on a work piece relative to the grinding wheel, a fluid motor to swivel said head in either direction, adjustable stops to limit'the swivelling movement of the head in either direction, means including a solenoidactuated control valve for controlling said swivel motor, a plurality of table dogs adjustably mounted on said table, and means including a switch actuated thereby for controlling said valve automatically to swivel said head in timed relation with the table movement.

10. In a grinding machine having a base, a transversely movable wheel head, a rotatable grinding wheel thereon, a pivotal mounting for the wheel head, means to ieed said head transversely, a longitudinally movable work table having a rotatable work support thereon, means for moving the table longitudinally successively to position spaced portions on a work piece relative to the grinding wheel, a fluid motor to swivel said head in either direction for a taper grinding operation, adjustable stops to limit the swivelling movement of the head in either direction, means includ g a solenoid-actuated control valve for controlling the fluid motor, means including an index pawl to facilitate locating the wheel head in a: central position for a truing operation, a fluid motor to actuate said pawl, means including a solenoid-actuated control valve therefor, a plurality of adjustable'dogs on said table, and a plurality of limit switches actuated by said dogs to actuate the control valves in timed relation with the longitudinal movement. of said table.

11. .In a grinding machine having a wheel slide base, awheel slide thereon, a swivel for said wheel slide. base means including a fluid motor toswivel said slide base, a rotatable wheel spindle on said slide to support a grinding wheel, a spindle reciprocating mechanism including a yoked member to reciprocatesaid spindle axially, means including a connecting rod to oscillate said yoke, and means to adjust the length of said :rod to facilitate positioning the reciprocatory stroke of the grinding wheel so that it is centered relative to, the pivotal axis of said swivel.

' 12. In a grinding machine having a trans versely movable wheel head, a rotatable grinding wheel thereon, a pivotal mounting for the head, means to feed said head transversely, a longitudinally movable work table having a rotatable work support thereon, means for moving the table longitudinally successively to position spaced portions of a work piece relative to the grinding wheel, means to swivel said head in either direction, and means actuated by and in timed relation with said table movement to control the swivel means so as to swivel said head in one direction to facilitate grinding a predetermined taper in one direction on part of the portions to be ground and to swivel said head in the opposite direction to facilitate grinding a predetermined taper in the opposite direction on the remainder of the portions to be ground.

13. In a cam grinding machine having a base, a transversely movable wheel head, a rotatable grinding wheel thereon, a vertically arranged pivotal mounting for the head, means to feed said head transversely, a longitudinally movable table, a rotatable cam shaft support thereon, means for moving the table longitudinally successively to position spaced cams in operative relation to the grinding wheel, means to swivel said head in either direction, adjustable stops to limit the swivelling movement of the head in either direction, and means actuated by and in timed relation with the table movement to control the swivelling means so as to alternately swivel said head in opposite directions after each cam has been ground to facilitate grinding a predetermined taper in opposite directions on alternate cams to be ground.

14. In a cam grinding machine having a base, a transversely movable wheel head, a rotatable grinding wheel thereon, a pivotal mounting for the head, means to feed said head transversely, a longitudinally movable table, a rotatable cam shaft support thereon, means for moving the table longitudinally successively to position spaced cams in operative relation to the grinding wheel, means to swivel said head in either direction, adjustable stops to limit the swivelling movement of the head in either direction, and means actuated by and in timed relation with the table movement to control the swivelling means so as to alternately swivel said head in opposite directions after each pair of cams has been ground to facilitate grinding a predetermined taper in opposite directions on alternate pairs of cams to be ground.

15. Ina cam grinding machine having a base, a transversely movable wheel head, a rotatable grinding wheel thereon, a pivotal mount for said wheel head, means to feed said head transversely, a longitudinally movable work table having a rotatable cam shaft support thereon, means for moving the table longitudinally successively to position successive cams in operative relation with the grinding wheel, means to swivel said head in either direction, adjustable stops to limit the swivelling movement of the head in either direction, and means automatically actuated by and in timed relation with the longitudinal movement of the table to control the swivel means so as to swivel the head in one direction to facilitate grinding a predetermined taper in one direction on a portion of the cams to be ground and to swivel said head in the opposite direction to facilitate grinding a predetermined taper in the opposite direction on the remainder of the cams to be ground.

16. In a grinding machine having a transversely movable wheel head, a swivelling support for said wheel head, means to swivel said head in opposite directions, means including adjustable stops for limiting the swiveling movement of the head in either direction for grinding tapers in opposite directions on a work piece, and means including a locating pawl for locating the wheel head in a central'position for a grinding wheel truing operation. I

1am a grindingma'chine having a base, a transversely movable wheel head having a rotatable grinding wheel thereon, a pivotal mounting for the wheel head, a longitudinally movable table having a rotatable work support thereon, means for moving the table longitudinally toposition a work piece relative to the grinding wheel, means to swivel said head in either direction to facilitate grinding tapers in opposite directions on spaced portions of the work piece, means including an index pawl to facilitate locating the wheel head in a central position for a truing operation, and-means actuated by and in timed relation with the longitudinal movement of the opposite directions after each cam has been table to control the movement of said pawl.

' 18. In a cam grinding machine having a base, a transversely movable wheel head, a rotatable grinding wheel mounted thereon, a pivotal mounting for the wheel head mounted on the base for swivelling movement about a vertical axis, a longitudinally movable table, a rotatable cam shaft support thereon, means for moving the table longitudinally successively to position spaced cams in operative relation to the grinding wheel, means toswivel said head in either direction, adjustable stops to limit the swivelling movement of the head in either direction, and means actuated by and in-timed relation with the table movement to control the swivelling means so as to alternately swivel said head in ground to facilitate grinding a predetermined taper in opposite directions on alternate cams to be ground.

19. In a grinding machine having a base pro--.

vided witha movable support that has means for rotatablysupporting a cam shaft to be ground: and provided with a movable support carrying; a rotatable peripherally operative grinding wheel having means for axially reciprocating said grinding wheel, means mounting and guiding;

said supports on said basefor relative movement in a direction longitudinally of the, axis of said cam shaft supporting means and for relative movement therebetween in a direction transverse of said axis and including means providing a. vertical pivot for said grinding Wheel support for swiveling it in opposite directions about avertical axis to provide respectively opposite angularities between the line along which said;

s erm 1% angularities, and means including spaced control elements and coacting actuatable control means between whichrelative movement takes place in =tim'ed relation with said relative longitudinal movement between said two supports *in said successive stages, for controlling said swivelingmeans to swivel said pivoted-support in one direction to grind -a taper on -a cam at one stationand to swivel said support in opposite direction to grind -a taper in opposite direction on a'cam atanother station.

20. A cam grinding machine -as claimed in claim 19 in which said'means for axially reciprocating said grinding wheel comprises 'an axially reciprocable grinding wheel driving spindle with a yoked member to reciprocate said spindle axially withdriving'means to oscillate said yoked member and including means of adjustable length to facilitate positioning thereciprocatory stroke of the grinding wheel so that its midpoint coincides with said vertical plane that includes said vertical pivotingaxis.

21. Tn a camjgrindmg machine having a base provided with a movable support carrying a rotatable grinding wheel "and provided with a movable support that has means for 'rotatably supporting 'a 'cam shaft to be ground, means mounting and guiding-said "supports :on said base for relative movement therebetween in a direction longitudinally of the axis of said cam shaft supporting means and for relative movement therebetween in a direction transverse f said axis and including means providing a vertical pivot'for one-of said supports for swiveling it "in opposite directions about a vertical-axis to provide respectively opposite angularities 'between the -face of the grinding wheel and the axis "of said rotatable cam shaft "supporting means for grinding opposite-tapers;means for e'fiecting'said first-'mentioned relative movement 'in successive stages to "successive grinding stations for individually positioning spacedcam-shaf-t cams and said grinding wheel in operative relation, means to swivel said vertically pivoted-support in either direction about said vertical axis, and means including spaced control elements and eoacting aotuatable control means-between which relative movement takes place in timed relation with said relative longitudin'al movemen'tin successive stages :between :said two supports, "forcontrolling said iSWiVlillg means to swivel-said pivoted support inxonerdirectionto grind a taper-on a -cam at oneestation and-toswivelsaid support inopposite :direction to grind =a taper in oppo'site direction on a cam at another station.

22. A cam grinding :machine :as' claimed in claim 211in which'themeansto swivelsaidverticallypivoted support comprises areversible -fluid motor and said spaced control elements and-coacting .actuatable control means therefor comprise respectively -a notched plate movable with one .of said supports and a plunger-like index 2'9 pawl enacting therewith whereby =the strdke of movement of said index pawl is controlled by said notched plate, and valve-means f or affecting the supply of iiuid to said fluid motor and 'ineluding valve means responsive to the position of :said index pawl relative to said notched plate.

A =cam grinding machine as claimed in claim'2-1 'in which the means to swivel said vertically pivoted support comprises reversible motor means and -said spaced control elements and coacting actuatable control means therefor comprise respectively a notched plate movable with one of said supports and a plunger-dike index pawl eoacting therewith whereby the strokeo'f movement -of-said indexpawl is-controlled bys'aid notched plate, said plunger-like index pawl having means operable in one direction upon the index pawl bottoming in said'notchedplate and operating in reverse direction upon said index pawl moving out of said notched =plate for-affecting the operation-oi said motor means.

24. 'In'a'cam grinding machine, abase having longitudinal and transverse *guideways one of which is formed in 'a member that is movably supportedon said'base for limited-shi'fting-move-. ment in reversible direction about a vertical axis thereby 'to change the "angularity between said two 'guideways in either direction from a "true QD-de gree angular relationship therebetween, .a table guided for longitudinal movement "in said longitudinal guid'ew'ays and having a rotatable cam shaft support thereon, a support movable along said transverse 'guideway and rotatably supporting a grinding wheel, means for moving the table longitudinally along Said longitudinal guideway to suceessive grinding stations to position spaeed-camsof acam shaft carried by said rotatable support in operative relation to the grindingwheel, and'motorm'eans for-moving said gui'deway member in either *direction about 'said vertical axis and including "control means there for coasting with means {that move with said table, for shifting B said gu'ideway member in one direction to-grind= a taper'on va cam at one stav tion-and to-shiftsaid'guidewaymember in oppo- REEERENGES CI'IED "The following references are 'Of vrecord in the file of -this patent:

UNITED STA IYES PATENTS