US1918147A - Carriage positioning mechanism for grinding machines - Google Patents

Description

July 11, 1933. V B; STOWELL 1,919,147

CARRIAGE POSITIONING MECHANISM FOR GRINDING MACHINES Filed Nov. 17, 1930 ,3 Sheets-Sheet 1 INVENTOR.

BYRON F S7'0WELL J7 BY W A TTORN E YS.

July 11, 1933. s. F. STOWELL CARRIAGE POSITIONING MECHANISM FOR GRINDING MACHINES 1950 3 Sheets-Sheet 2 Filed Nov. 17,

1N VEN TOR. Brm FSMWELL ATTORNEY July 11, 1933. 5' STOWELL 1,918,147

CARRIAGE POSITIONING MECHANISM FOR GRINDING MACHINES Filed Nov 17, 1930 5 Sheets-Sheet 5 44 23 1 z; 70 7/ a; 23 67 M 37 .5 //,Z //l g 1 2r ///I/ Ag i@i J 5 0 O i 5 $1 x I I i I m I IN VEN TOR.

A TTORNEYS.

Patented July 11, 1933 lrrren s'rar rarest r'r ca .w LL, or BI-.Ni "NE cciirranv,

caianraen Posmroni'i em ss; assienoa T van n'omvmn xmssacnosnrrs, A oonrona'rron OF 7G HESEAISIISIKE GRINDER MACHINES Application. filed November 1?, 1930. Serial No. 496,178.

a .rhinr-s of this type it is necessary to pro ide an accuratemechanical feed in a direction at right angles to the axis of the grindmg wheel so that the wheel may be fed gr. d y and progressively against he work as g proceeds. ,l hen it desired to remove the t: from the worln two motions 1 righ angles to each other are necessary. these is a rapid motion in the same fixer-lion as the slow feed but generally separate from thistced in order to provide quick- The second is. at right angles to other words parallel to the axis of the grinding wheel. The latter motion serves to withdraw the grinding wheel axially out of the ball bearing ring which is being mind and can only be made after the first motion is completed so that the grinding wheel will clear the annular ground recess in the bearing race.

placed in position for the start of a grinding operation.

One object of the invention is to provide a single com rol by which the two rough positioning motions oil. the tool head may be accomplished. A further object is to provide in :hanisni which will automatically reset the accurate cross feed whenever the grinding tool is witlnjlrawn from its operative position. A further obj octis to provide mechanism governed by this same control by which the machine will be automatically stopped by the operation of shifting the tool out of grinding position. A further object is to provide an interlocking control between the various motions so that the machine cannot be operated in a manner to cause injury to the work. Other and further objects will An inverse sequence of motions will occur when the wheel 1S bein D freely mounted upon appear from the following description and claims. Y

The invention will now be described 1n connection with the accompanying drawings,

in which:

Fig. 1 1s a top plan view of the tool head end of a grinding machine embodying my invention Fig. 2 is a side elevation thereof;

1 i g. 3 is a partial top plan on an enlarged scale showing the parts in, a different position oi operation;

Fig. 4 is a similar View showing a still d i .lierent positi on of operation Fig. 5 is a section on line 5-5 of Fig. l;

F lg. (S a partial bottom plan View taken on line 66 of Fig. 2; i

Fig. '2' is a section on line 77 of Fig. 4;

Fig. 8 is a partialrear elevation of the machine; and i i Fig. 9 a detail on line 99 or Fig.7.

The machine is mounted upon a frame 10 waich. at its tool head end carries. ways 11 (Fig. 7). Slnling in these waysis a slide 12 which constitutes the means for moving the tool head in a direction parallel to the axis ol the rinding wheel An accurate limiting position of this slide is determined by means of a bracket 13 ig. 2) overhanging the frame and carrying stop screw 14, sothat when the slide is moved the desired amount the screw will abut the frame and stop any further movement.

Y Mounted in the top of the slide 12 is a sleeve 15 (Fig. 7) having a vertical bore in which rotates a shaft 16. The lower end of this shaft carries a gear 17 meshing with a rack 18 fixed to the frame. By rotating the shaft 16 it is thus possible to move the slide 12 along its ways with a comparatively rapid motion. In order to rotate the shaft, anarm 19 is splitas at 20 6) and is drawn together around the shaft by means of a bolt 21. The arm 19 is not directly moved by the operator, but is actuated by connections to be described by a second arm 22 (Fig. 7) shaft 16. The arm 22 has a cam 23 secured to it by a bolt 24: and serving a purpose to be describedlater. Bearing upon the top of the cam is a cap screw threaded into the shaft and thus serving to maintain both the arm and the cam in position upon the shaft, while permitting their free rotation in unison. Upon the lower side of the arm 22 is a bracket 26 (Figs. 3 and 6) to which is pivoted at 27 a latch 28. This latch is normally drawn by a spring 29 into the position shown in Figs. 3 and 6 where its end bears against a beveled portion of the lower arm 19. As long as the latch remains in this position, movement of the arm 22 from the position of Fig. 1 to that of Fig. 3 will cause the arm 19 to move with it and through the rack and pinion described will cause reciprocation of the slide 12 in the ways 11.

hen the slide 12 has reached the position of Fig. 3, its stop screw 14 is abutted against the frame, preventing any further movement in that direction. This of course stops the movement of the arm 19 and also of the arm 22 which is at this moment connected to the first arm by the latch 28. In order to continue the motion of the upper arm and pro- 1 duce the further positioning movements of the machine which will be described later, it is necessary to disengage the latch 28 from the lower arm. For this purpose the latch is provided at its lower side with a boss 31 connected by a link 32 (Figs. 5 and 6) with j a boss or yoke 33 fixed to the lower side of a shaft 34 freely rotatable in the arm 22. At its outer end this shaft has a handle 35 (Fig. 3) secured to it by a key 36 and screw 37. If the handle is turned so that its top moves to the left (as viewed in Fig. 3), the latch 28 will be swung and its end moved beyond the end of the lower arm 19. Motion of the upper arm can then be continued as indicated in Fig.4.

In order to hold the lowerarm 19 in position after it has been disengaged by the upper arm, a latch 38 (Fig. 3) having a hooked portion 39 adapted to engage a latch plate 40 is provided. The latch plate is adjustably mounted by a bolt 41 in an arcuate T-slot 42 formed in a flange 43 of the sleeve 15. The tail 44 of this latch engages a stop 45 carried by the bracket 26. The latch is pivoted at 46 (Fig. 6) to the lower arm and is urged into latching position by a spring 47. The latch plate 40 is so adjusted in its slot that the latch will just engage it as stop 14 strikes the frame. Having once been set, it may thereafter be left in its adjusted position until the setting of the stop 14 is changed.

Before considering the remaining functions of the control arms, it is necessary to describe the cross slide mechanism which carries the tool head. Upon the top of the slide 12 are formed ways 50 (Figs. 2 and 8) upon which reci'procates an intermediate slide 51. A'nut 52 secured to this slide has threaded into it a screw threaded shaft 53 which is held against axial movement in the slide 12 and which bears a ratchet wheel 54. vThis ratchet wheel may be rotated automatically in the usual way to cause a slow and accurate cross feed movement of the slide 51. Upon the top of the slide 51 are formed ways 55 in which run a top slide 56. The top slide itself is preferably provided with ways 57 in which a separate motor slide, not shown, is mounted. The tool spindle 59 carrying the grinding wheel 60 is supported in this slide 56.

To the rear end of the intermediate slide 51 is secured a plate 61 (Fig. 3) upon which the nut 52 may conveniently be mounted. The plate 61 also carries a stop screw 62 positioned to lie in the path of the top slide 56 and limit its outward movement. The plate also is apertured to permit the passage of a stud 63 secured to the top slide and bearing stop nuts 64 serving to limit travel of the top slide in the opposite direction.

A stud 65 is secured to the top slide and has a fixed collar 66 and a movable collar 67 pressed toward it by a spring 68 compressed between the movable collar 67 and a fixed collar 69. The end of an arm 7 O pivoted at 71 upon a bracket 72 extending from the slide 12 is apertured to receive the stud 65 and is positioned between the collars 66 and 67. The arm is formed as a bell crank and its other end is provided with a flat surface 7 3 against which the cam 23 is adapted to bear. As the cam presses the adjacent end of the bell crank to the left as viewed in Fig. 3, the other arm of the bell crank will exert a pull on. the slide 56 and will cause it to be drawn outwardly toward the stop 62. The cam is provided with an arc shaft slot 74 through which passes the bolt 24 previously mentioned, thus permitting the cam to be adjusted in any desired angular position. In order to keep the surface 73 pressed toward the cam, a spring 76 is provided, compressed between a fixed collar 77 and a movable collar 78 on a rod 79 secured to the intermediate slide 51.

Mechanism isalso provided for resetting the slow cross feed given by the shaft 53 when the slides are moved to their inactive position. For this purpose a gear 80 (Fig. 2) is secured to the shaft 53 and has meshing with it a train of gears 81, 82 and 83. Adapted to mesh with the last of these gears is a rack 84 pivoted at 85 to the frame so that it may oscillate between a position meshing with the gear 83 and a position just below it. A lifter 86 is pivoted to the frame at 87 below the rack and has a rod 88 connected to it which passes through a bracket 89 projecting downwardly from the slide 12. Vithin a recess in the bracket are fiber blocks 90 and 91 (Fig. 7) encircling the rod 88 and pressed together by a spring 92 held in place by a cap 93. The blocks bear against the rod with just sulficient force to exert a frictional drag upon it.

active position, the lifter will be rotated in the opposite way and will raise the rack so that it will mesh with the gear 83. Since this gear moves with the slide 12 and the rack is stationary, a rotation will be imparted to 1 the shaft 53 on a rearward motion of the slide. This is sufficient to cause the amount of forward rotation given to the shaft 53 dur-v ing the feeding movement to be compensated for.

It will be noted from the description above that a single motion of the handle from the position of Fig. 4 to that of Fig. 1 will first move the grinding wheel in a direction at right angles to its axis to disengage it from the work piece which has just been ground, and then will move the wheel in the direction of its axis to withdraw it from the locality of the work piece and permit the latter to be removed without hindrance. To remove the work piece, however, it is necessary to stop its rotation and also the oscillation of the head which carries it. This rotation and oscillation may be imparted to the work head by any suitable mechanism operated from a main shaft 190 9). A suitable mechanism is shown in the patent to Van Norman, No. 1,722,691, July 30, 1929, the shaft 190 in the present case corresponding to the shaft S of the patent. Mounted upon the shaft 190 a tight pulley 191, a loose pulley 192, and a brake disk 7 193. A belt from any suitable power source passes over the pulleys, being maintained under the control of a belt shifter 94 carried by a sliding rod 95. A brake 96 is also carried by the rod so that when the belt is shifted to the loose pulley not only will the driving force be cut off from the shaft but a braking force will be applied to bring it to rest quickly.

The rod 95 is constantly urged towards the left in Fig. 9 by a spring 97. An arm 98 is secured to a short pivot shaft 99 and has a pin and slot connection 100 with the rod. Also secured to the shaft 99 is an arm 101 joined by a link 102 (Fig. 7) with a treadle 103. By depressing the treadle, the rod 95 is shifted in a direction to cause the belt to be moved onto the tight pulley. \Vhen once depressed it is neld in that position by a rod 104 sliding in the frame and urged to the left in Fig. 7 by a spring 105 compressed between the frame and a collar 106 on the rod. In its left hand position the end of the rod projects beyond the side of the arm 101, the motion of the rod being limited by contact of the collar with the face of the arm (Fig.

The end of the rod 10% remote from the collar carries a. rounded disk 107 (Fig. 7) which lies adjacent the lower end of an arm arm 101.

from the first slide moving mechanism, and

108 secured to a "shaft 109 ourn-al'ed in a bracket 110 securedto the slide 51. Asecond arm 111 secured to the shaft is fastened at its upper end to'a rod 112 projecting from the slide 56. 'Asthe latter slide is moved to free the grinding wheel from its work, the disk 107 is struck by the arm 108 and pushed far enough to the right in Fig. 7 to withdraw the end of rod 104 from its position beside the The rod 95 is thus freed for motion under the influence of the spring 97 in a direction to shift the belt to the loose pulley 92. By this mechanism the power to the machine is placed under the control of the operating handle A single swing of this handle moves the grinding wheel transversely to free it from the work, shuts 05 the power, moves the grinding wheel longitudinally, and resets the slow feeding mechanism.

hat I claim is:

1. A grinding machine having a pair of slides at an angle to each other, a single handle movable through an arc, mechanism operal le by the handle while moving through one portion of said arc for moving one slide, and mechanism operable by the handle while moving through another portion of said are for moving the other slide. I

2. A grinding machine having a work head, a first slide movable toward and away from the work head, a second slidemovable upon the first at an angle thereto, a tool head carried by thesecond slide, a handle pivoted for rotation upon the first slide, mechanism operable by the handle during one portion of its rotation for moving the first slide, and mechanism operable by the handle during another part of its rotation for moving the second slide.

3. A grinding machine having a work head, a first slide movable toward and "away from the work head, asecond slide movable upon the first at an angle thereto, a tool head ca-rriedloy the second slide, a. handle pivoted for rotation upon the first slide, a stop limiting the motion of the first slide, mechanism operable by the handle during the first part of its rotation for moving the first slide, a device carried by the handle for releasing it mechanism operable by the continued rotation of the handle for movingthe second slide.

4. A grinding machine as claimed in claim 3 in which the releasing device carried by the handle comprises a manipulable element rotatable to cause release. I

5. A grinding machine comprising a frame, a slide mounted 011 the frame, a second slide mounted on the first at an angle to it, a shaft j ournaled in the first slide, a rack and pinion connection between the shaft and the frame, a handle rotatable on the shaft, pawl mech anism releasably connecting the handle to the shaft, a bell crank pivoted on said slide, a

cam carried by the handle acting on the bell crank to rock it upon its pivot, and connections betweenthe bell crank and the second slide.

(3. A grinding machine comprising a work head, a first slide, means for moving the first slide towards and away from the work head, a second slide movable u )011 the first slide at an angle thereto, a thirdslide movable upon the second slide, a tool head carried by the third slide, mechanism for moving the third slide upon the second slide to place the tool head in or out of operative relation with the work head, means for moving the second slide upon the first slide with a slow tool-feeding movement, and mechanism automatically operable upon the movement of the first slide away from active position to reverse the slow tool-feeding movement of the second slide and return it substantially to its original position. 7. A grinding machine having rotary work holding and wheel carrying heads, means for moving one head relatively to the other in directions substantially parallel with and right angularly to the axis of its rotation, slow feeding meclninisni for moving said head in one direction and. a single lever controlling, through progressive movements thereof, mechanisms operable to effect a rapid withdrawal of said, head in each of its directions of movement and to impart an ac celerated reverse movement to said feeding mechanism.

8. A grinding machine having rotary work means for supporting one of said heads for movement relative tothe other in two directions, one substantially parallel to and the other substantially at right angles to the axis of rotation of the head, mechanism {or moving said head at a slow rate of feed in one of said directions, a progressively movable member, and mechanisnr actuable by progressive movementoii said'memher for moving said head-in a sequence of quick acting movements in both of said two direct-ions.

10. A grinding machine or the like having rotary work holding and tool carrying heads.-

means for supporting one of said headsfor movement relative to the other in two directions, one :nibstantially parallel to and the other substantially at right angles to the axis of rotation of the head, mechanism for moving said head at a slow rate of feed in one of said directions, a progressively movable member. mechanism actuable by progressive movement ot-said member for moving said head in a sequence of quick acting movements in both of said two directions, and separatc mechanism operable through movement of said head in one of said directions of travel. to effect a reversed and accelerated movement to said slowfeeding mechanism.

In testimony whereof I have aflixed my signature.

BYRON r. sToWnLL.

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