US2506495A - Indexing mechanism - Google Patents

Description

May 2, 1950 R. E. FLANDERs ETAL 2,506,495

INDEXING MECHANISM Filed Oct. 16,v 1945 3 Sheets-Sheet 1 j @i fag@ J 43. ImMzZ/f #MMWWW May 2, 1950 R. E. FLANDERS ETAL 2,506,495

INDEXING MEcHAmsu Filed Oct. 16, 1945 y 3 Sheets-Sheet 2 May 2, 1950 R. E. FLANDERs ET AL 2,506,495

INDEXING MECHANISM Filed 001;.. 16, 1945 v 3 Sheets-Sheet 3 R 1 A 17 if 4 f' ,/f ff f4 J7 j? J/ ff is? la@ @wir l 1 Vfl/ gli@ l j MM2? M y MMw/y while the gear 1 is stationary, the spindle 3 may be turned so as to displace the spindle angularly from its previous relation to the drive gear 1 and by so turning the cage 2| through the necessary angular extent, the work is stepped around so that the grinding wheel on the next pass of the carriage grinds on a thread face angularly spaced from that previously ground and this may be made to correspond with the angular spacing of the thread starts of the work. In order to produce this angular motion of the spindle 3 with reference to its driving mechanism, means are provided for turning the cage the required amount, at the end of each grinding pass, at other times the cage being held stationary so that the grinding is effected accurately on the thread face initially presented thereto. To this end the cage is formed with a worm wheel portion 25 with which meshes a worm 26 on a shaft 21, and as shown best in Figure 2, this shaft 21 is connected through change gears 28 and 29 with a second shaft 30.

The shaft 38, as shown best in Figure 3, carries a Worm wheel 3| and a spiral cam disk 32. Meshing with the worm wheel 3i is a worm 33 carried by a wo-rm shaft 3d. As shown best in Figure 6, the worm 33 is mounted on the shaft 311 with capability of axial motion, the worm portion being mounted on a splined quill lportion 35 of the shaft 34 and is normally pressed to one limit of its axial motion as by a spring i seated in a central bore 31 in the shaft 3s and reacting between a slide 38 extending through a slot 39 in the shaft 34 and which engages over one end of the worm 33 and a cap di! threaded onto the outer end of the worm shaft 35, This worm shaft 34 extends outwardly of a casing 4| where it has keyed thereto a pulley 42 connected as through a driving belt 44 with a motor 45. By rotation of this motor 45, it will be evident that the worm 33 will be driven and through the Worm wheel 3|, the shaft 30 will be driven, and this through its change gears will drive the worm shaft 21 thus to index the spindle 3 with reference to its drive mechanism.

The means for controlling the rotation of the motor 45 comprises a solenoid 59 (Figures 3 and 9) which is energized as the carriage 2 approaches the end of its stroke, as by the closing of a switch through a carriage dog 52. The energization `of the solenoid 5B pulls upwardly a plunger 55 which is connected to a latch dog 56 (see Figure 3) pivoted at 51. This pulls the latch dog away from the locking shoulder 53 of the spiral cam 32, thus unlocking the shaft 3d for rotation. The dog 55 also carries a switch actuating arm 6D which lifts a switch actuating element 6| against `the pressure of a spring 62 and closes a switch 63. The closing of the switch S3, as shown in Figure 9, closes a circuit from the lines a and b through a relay coil 64 which closes a pair of switch arms 65 and 66. The closing of the switch arm 65 closes a holding circuit for the relay B4 so that the breaking of the switch at 63 thereafter is not effective to release the relay, and the closing of the switch 66 acts to energize the motor d5. The rotation of the motor then turns the shaft 38 through the worm 33 and the worm wheel 3|, and turns the cage 2|. This action continues until a cam 18 adjustably fixed to the spiral cam 32 engages and pushes outwardly a switch actuating element 1| which opens the switch 12 in `the holding circuit of the relay 64 which deenergizes the relay coil 64 opening the switch arms 55 and 66 which stops the rotation of the motor 45,

Any continued rotation of the motor 45 after the rotation of the shaft 30 is positively stopped by the dog 56 contacting with the shoulder 58 is expended in moving the worm wheel 33 along the shaft 34 in opposition to the spring 36, this mechanism thus acting as a yielding take-up to prevent breakage of the parts when the motor overruns and to make sure that the motor will run a sufficient length of time to complete the indexing action.

Means are also provided by which the direction ofindexing may be reversed, depending upon whether right or left hand threads are being ground. This mechanism is shown particularly in Figures 4 and 5. The drive shaft 15 which drives the gear 1 is connected thereto through a. sliding gear 11 on the shaft 15 which meshes directly with the gear 1, or to it through an idler shaft 18 having two -gears 19 and 80. The gear 8U meshes with the gear 1, and the gear 19 meshes with the gear 11 when the gear 11 is slid out of mesh with the gear 1 and into mesh with the gear 19. The sliding motion of the `gear 11 is produced by the axial motion of a rack bar 8l with the rack teeth `of which meshes a pinion 82 on a reversing rock shaft 83 provided with a handle 84 on. the outside of the gear casing 85 (see Figure l). When the handle extends upwardly, the machine is adjusted for right hand threads, and when it is rocked downwardly the rack bar 8| is moved to its other position adjusted for left hand threads, thus reversing the relative directions of motion of the spindle and traverse. Both are reversed together to reverse the traverse direction as described in the Flanders patent to which referenxce has already been made.

From the foregoing description of an embodi-v ment of this invention it sho-uid be evident to those skilled in the art that various changes and modications might be made without departing from the spirit or scope of this invention.

We claim:

l. In a machine of the class described, a reciprocating carriage, a work spindle journaled in said carriage in line with its direction of reciprocation, a bevel gear fixed to said spindle, a spider journaled on said spindle, a planetary gear journaled on said spider and meshing with said beveled gear, a sleeve journaled on said spindle, a gear carried by said sleeve and `with which said planetary gear meshes, means for rotating said sleeve and thereby through said planetary gear said spindle when said spider is stationary, means for rotating said spider to thereby adjust said spindle angularly relative to said sleeve, and means for reciprocating said carriage in time with the rotation of said sleeve.

2. In a machine of the class described, a recipe rocating carriage, a work spindle journaled in said carriage in line with its direction of reciprocation, a bevel gear fixed to said spindle, a spider journaled on said spindle, a planetary gear journaled on said spider and meshing with said beveled gear, a sleeve journaled on said spindle, 'a gear carried by said sleeve and with which said planetary gear meshes, means for rotating said sleeve and thereby through said planetary gear said spindle when said spider is stationary, mean's for rotating said spider to thereby adjust said spindle angularly relative to said sleeve, and means for reciprocating said carriage in time with the rotation of said sleeve, said spindle being rotatable in either direction and said sleeve having a lost motion connection with said rotating 5 means for taking up backlash in said reciprocating means.

3. In a machine of the class described, a rotary work spindle, a grinding wheel, means for rotating said spindle land for traversing said spindle lengthwise in predetermined relation,means for turning said spindle` angularly relative toits traverse position from said predetermined relation at predetermined times, power means for actuating said turning means, means for positively stopping said turning means after a predetermined extent of angular motion, and a yielding take-up interposed between said power means and turning means for absorbingthe eiTect of said power means after such positive stopping has been effected until the power means stops.

4. In a machine of the class described, a rotary work spindle,a grinding wheel,means for rotating said spindle and for traversing said spindle lengthwise in predetermined qrelation, means for turning said spindle angularly relative to its traverse position from said predetermined relation at predetermined times, power means for actuating said turning means, means for positively stopping said turning means after a predetermined extent of angular motion, a drive interposed between said power means and turning means including a driving Worm and a driven worm wheel, means supporting said worm for axial motion, and a spring pressing said Worm to a limit of motion in one direction, said spring permitting axial, motion of said worm opposed thereby on continued operation of said power means after such positive stopping has been effected.

5. In a machine of the class described, a rotary work spindle, means for rotating said spindle, means for moving said spindle axially in predetermined relation to such rotation, means including a planetary transmission having a normally stationary part between said rotating and said moving means, said normally stationary part determining by its position said predetermined relation, a motor for turning said normally stationary part, means actuated by said spindle when it reaches a predetermined axial position for energizing said motor, and means actuated when said normally stationary part reaches a predetermined angular position to de-energize said motor and to stop its own rotation.

6. In a machine of the class described, a, rotary work spindle, means for rotating said spindle, means for moving said spindle axially in predetermined relation to such rotation, means including a planetary transmission having a, normally stationary part between said rotating and said moving means, said normally stationary part determining by its position said predetermined relation a motor for turning said normally stationary part, means actuated by said spindle when it reaches a predetermined axial position for energizing said motor, means actuated automatically to de-energize said motor and to stop its own rotation when said part has been rotated through said predetermined angular distance, and a spring take-up between said motor and part permitting over-running of said motor after the stopping of said part.

7. In a machine of the class described, a rotary work spindle, means for rotating said spindle, means for moving said spindle axially in predetermined relation to said rotation, means including a planetary transmission between said rotating means and said moving means, said planetary transmission including a normally stationary part determining by its position said predetermined relation, and power means for automatically turning said normally stationary part at intervals to thereby change said predetermined relation.

8. In a machine of the class described, a rotary work spindle, means for rotating said spindle, means for moving said spindle axially in predetermined relation to said rotation, means including a planetary transmission between said rotating means and said moving means, said planetary transmission including a normally stationary part determining by its position said predetermined relation, and power means for automatically turning said normally stationary part when said spindle reaches a predetermined axial position to thereby change said predetermined relation.

RALPH E. FLANDERS. LEE DAVIS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,622,628 Durkee i Mar. 29, 1927 1,957,317 Burt et al May 1, 1934 1,981,263 Croft Nov. 20, 1934 2,307,238 Ross Jan. 5, 1943

Images