US1691144A - Work-driving device - Google Patents

Description

Nov. 13', 1928. 1,691,144 J. BATH WORK DRI VI NG DEVICE Original Filed Dec. 2 1921 2 Sheets-Sheet 1 111 III 107 [we/750k 1 H omg s Nov. 13, 1928.-

J. BATH WORK DRIVING DEVICE Original Filed Dec. 27. 1921 2 Sheets-Sheet 2 1Z0 (3! v [wenfar omg/s Patented Nov. 13, 1928.

"ran some PATENT OFFICE.

JOHN BATH, OF WORCESTER, MASSACHUSETTS.

wonx-nnivxno DEVICE.

Original application filed December 27, 1921, Serial No. 524,817 Divided and this application filed December 14, 1925. Serial No. 75,201. i

This application is a divisipn of my prior application Serial No; 52%,811, filedDece n- 'ber 27, 1. 21. and relates to a device tor drivinsrotating work. Whilethe device 1s capable of general ap 'ilication, 1t 1s partlcularly adapted for use in "engine lathes, threading machines; thread grindlng machines and other similar apparatus.

The general object of my inventi1 1s to 10 provide a work driving device which ls eftective to turn the work in either direction, and to provide means by which the baclclash in the machine, 011 reversal, may be accurately determined and by which it may be taken up in the WOI'K driving device.

F1 g. 1 is a sectional elevation of my work driving; device taken along the line 11 in l ig. 7; 1 i

iii 2 is a partial plan view looking in the direction of the arrow 2 in F1 1;

P's 8 4 5 and 6 are detail sectional. views taken respectively along the lines 88, 41- 4, 55, 0-6, of Fig. 7;

Fig. 7 is an end elevation of the taco plate and work driving attachments;

Fig. 8 is a plan view of certain parts of the machine, illustrating the means by which the amount of back lash is determined; and

9 is an end elevation looking in the direction of the arrow 9 in Fig. 8.

l: have shown my invention as applied to a thread grinding machine. My improved work drivingdcvice comprises ausual face pl to. 105 which is threaded on the end of a spindle 60 (Fig. 1) rotatable in a head stock 32. The plate 105 isprovided with a hub or extension 106 on which is mounted a ring 107' supporting a pair of work driving dogs 108. These dogs are radially adjustable on the ring 107 and are secured thereto by binding screws 109. The inner ends of the dogs are shaped to receive and engage the shank of a tap or other articlcto be ground, which is held on the head and tail centers of the machine.

The ring 1071s flanged and is held against the :t'uce plate by an outerring 110 secured to the face plate by binding screws 111. and 112 (1 igs. 7 and 9). A slot 113 extends nearly around the ring 110 and the binding screw 111 is shown as extending; through this slot, while the screw 112 extends through a hole in the ring 110 between the ends of the slot 113. A series of tapped holes 114: may be the blocks provided in the face plate to receive the screws 111 and 112.

Segmental blocks 115 and 116 (Figs. 4 and '1') are provided with curved ribs'or projections 117' (Fig-f 5) fitting the segmental slot 113. These blocks are secured in anguiarly adjusted position by clamping bolts 118 and nuts 119 (Fig. 1). A spring handle 120 (F 1g. 7) is secured to each block 115 or 116 and is provided with aspur 121 (Fig. 5) en aging notches 110 (Figs. 7 and, 9) iormed at the outer edge of the ring 110.-

A similar spring handle 122 (Fig. 9) is securei to the inner ring 107, this handle being provided with a socket or recess 123 adapted to receive pins or studs 124 formed on'the ends of the bolts 118 which secure theblocks 115 and 116 in posi ion. Stops 125 and 126 (Figs. 3 and 7) are also slidable in the slot 113 of the ring 110 and may be clamped in position as will be hereinafter described.

In the operation of my improved machine 115 and 116 are so located that the movement of the handle 122 from one pin or stud 1241 to the other will cause an angular movement oil the dogs 108 exactly equal to the back lash-in the connections between the work spindle and the grinding wheel table. The extent of this angular adjustment ofthe work required with a particular set-up of the machine is determined experimentally by use of the indicating device shown in Figs. Sand 9. Y

An arm 180 (Fig. 8) is fixed on the, wheel carriage (not shown) and extends forwardly and upwardly to a position for engagement by. the short end of an index lever 131, pivotcd at 132 on a stand 133. The stand is adjustably secured to the head stock 32 by a clamping belt 184. Alock plate 135 is slidably mounted inguide-ways 136 on the head stock 32 and may be secured in adjusted position. by a clamping bolt 137. An index or zero line is formed on one of the guide-Ways- 136 reference mark torthe index lever 131.

In order to determine the exact amount of back lash in the connections between the spindle and thew heel carriage, the spindle is niovedin the direction in which ithas been rotating until the handle 122 of the dogsupporting ring 1071s aligned with the jaws of the lock plate 135. This plate is then advanced in its guide-ways 186 until itrej leases the handle from the pin or stud 1241 on which it has been seated and looks it from further angular movement. The stand 133 of the index lever or pointer 131 is then adjusted so that the rear end of the pointer will be pressed against the arm 130 by the pointer spring 188, while at the same time the end ofthe pointer co-incides with the Zero mark on the guide-way 136.

The spindle 60 is then turned backward or in the opposite direction to that in which it has been rotating until the wheel carriage begins to move, such movement being inthat the wheel when thus adjusted engages slightly harder on one side than on the other, one of the blocks 115 or 116 may be further adjusted by moving its handle 120 one or more notches along the ring .110.

When adjustment is once made for a particular set-up of the machine, no further attention .is necessary beyond swinging the handle 122 from one stud 124 to the other at each end. of the wheel travel. The output of the machine is thus greatly increased, as the usual idle returnteed of the grinding wheel is entirely avoided.

When grinding certain types of thread, such as the Acme thread, it is sometimes desirable to feed the wheel sideways to widen the thread groove. The stops 125 are then used to preserve the original setting so that the slides 115 or 116 may be moved the required number of notches sidewaysto, widen the thread and may then be returned to their original positions when a new thread is to. be ground and widened.

The face plate 105 may be provided with graduations as shown in Fig. 2 and the ring 110 may have an index mark co-operatlng therewith to indicate the angular relation .of these parts.

These graduations are usetul when it is desired to advance the ring a certain angular amount relative to the faceplate.

Having described the construction and operation of my improved work driving de vice, it will be-seen that I have provided a simple and efiective means for accurately determiningthe back lash in a machine, such as a thread grinding machine, and "for taking up the work lash upon the reversal'of the machine, thus making the machine operative for many purposes on both forward and backward travel and eliminating the idle return stroke.

Having thus described my invention and the advantages thereof, I do not wish to be limited tothe details herein disclosed otherwise than as set forth in the claims but what I claim is 1. In a thread grinding machine, a head stock, a work supporting spindle rotatable therein, a work driving member mounted thereon, and means on said head stock eifece tive to release said member from said spindle and to hold said released member in fixed angular position.

.2. In a thread grinding machine, a work spindle, a face plate, a pair of driving dogs, a ring supportin said dogs, said ring being rotatably mounted on said plate, an

arm on said ring, and a pair of locating devices, angularly ad ustablev on said plate and means to hold said devices in fixed relation to said plate after selective adjustment thereon, saiddevices thereafter co-operating with said arm to retain said ring and dogs in either one of two selected and definite angular positions.

3. In a thread grinding machine, a work spindle, a face plate, apair of driving dogs,

a ring supporting said dogs, said ring being I rotatably mounted on said plate, and means to adjust and secure said ring on said plate, said means including a spring arm on said ring and a toothed member secured to said face plate, the teeth of said member cooperating with said arm to determine the position of said ring.

4. In a thread grinding machine, a work spindle, a face plate, a pair of drivingdogs,

a ring supporting said dogs, said ring be-' ing rotatably mounted on said plate, a pair of locating blocks, spring arms on said ring and blocks, a member secured to said plate and having teeth engaged by said arms to position the same, and additional position-- ing devices on said blocks co-operating with the arm on said ring.

p 5. A work driving device comprising a work spindle, a supporting member rotatable therewith, w'ork engaging. elements mounted on said supporting member, means to simultaneously adjust all of said engaging elements angularly relative to said supporting member, means for limiting the angular adjustment of said engaging elements, means for positively fixing the limiting positions, and meansto determine slight additonal angular adjustments relative to said positive limiting means,

In testimony whereof I have hereunto affixed my signature. a JOHN BATH.

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