US2562284A

US2562284A - Tracer mechanism

Info

Publication number: US2562284A
Application number: US584003A
Authority: US
Inventors: William L Tancred
Original assignee: Jones and Lamson Machine Co
Current assignee: Jones and Lamson Machine Co
Priority date: 1945-03-21
Filing date: 1945-03-21
Publication date: 1951-07-31
Anticipated expiration: 1968-07-31

Description

July 31, 1951 1.. TANCRED TRACER MECHANISM Filed March 21, 1945 s Sheets-Sheet 1 w W. L. TANCRED TRACER MECHANISM July 31, 195] 6 Sheets-Sheet 2 Filed March 21, 1945 INVENTOR. fZZZlflwffdwzfi July 31, 1951 w. 1.. TANCRED ,5

TRACER MECHANISM Filed March 21, 1945 6 Sheets-Sheet 5 LN VEN TOR.

July 31, 1951 w. L. TANCRED 2,562,234

TRACER MECHANISM Filed March 21, 1945 6 sheets-sheet 4 IN V EN TOR.

Jul 31,1951 w. L. TANCRED TRACER MECHANISM e Sheets-Sheet 5 Filed March 21, 1945 w f/ W IN V EN TOR. WZZ, [fa/21w July 31, 1951 w. L. TANCRED TRACER MECHANISM 6 Sheets-Sheet 6 Filed March 21, 1945 IN V EN TOR. i izmzd www Patented July 31, 1951 atta n TRACER MECHANISM William L. Tancred, Springfield, Vt, assignor to Jones & Lamson Machine Company, Springfield, Vt., a corporation of Vermont Application March 21, 1945, Serial No. 584,003

Claims. 1

trace the pattern with great accuracy and whichwill automatically follow around the pattern contour throughout a complete circumference when once presented thereto. To these ends the tracer comprises a pair of normally concentric elements, one enclosing the other, the pattern-engaging feeler carried by the outer of these elements, and both being yieldingly fulcrumed at spaced points to an outer casing, the fulcrum points of the inner element being much nearer to the feeler than the fulcrum point of the outer element. A slight movement of the feeler in any direction brings the two elements toward each other remote from the feeler and actuates a feed or traverse control, or both. After contact between the elements is established, a return relative motion of the control which moves the feeler or Work is produced, tending to cause separation of the elements remote from the feeler. These motions of the two elements are then caused to control motors for moving the tracer and pattern in angularly related directions, the tracer following the pattern so that a tool may follow the same path as the tracer onthe pattern relative to. work.

Another object of this invention is to provide a synchronization of tracer control movements to energize tool, head motors for uniform and continuous cutting of work to conform with the pattern contour. Thus, if the operator should leave the machine, the tracer will continuously repeat over the pattern contour path until the machine is stopped.

A further object of the invention is to provide a tracer and pattern mounting for a turret lathe whereby the tracer and pattern may control the operationof a tool at one tooling station of the turret but will not interfere with any desired op-erationsat other tooling stations of the turret for which settings have been made.

For a more complete understanding of this invention, reference may be had to the accompanying drawings in which Figure 1 is a cross sectional view on line I! of Figure 2 through a tracer and controlling valve mechanism embodying the invention.

Figures 2 and 3 are sectional views on lines 2--2 and 3-3, respectively, of Figure 1.'

2 Figures 41 and 5 are sectional views on the correspondingly numbered section lines of Figure 2. Figure 6 is a perspective view partly in section of the tracer and related parts.

Figure 7 is a diagrammatic View of the power 7 system of a machine tool controlled by the tracer mechanism of Figures 1 to 5, inclusive.

Figures 8 to 15, inclusive, show various controlling positions of the tracer elements corresponding to relative tracer and work positions shown in the correspondingly numbered views with the addenda a as 8a to- 15a, respectively.

Figure 16 is a view similar to Figure 2, but showing combined electrical and hydraulic mechanism V Figure 17 is a sectional view on line I1l'l of Figure 16, together with a diagram of the power system and controls.

Figure 18 is a view similar to a portion of Figure 1, but showing a modification.

Figures 19 and 20 are top planand front elevational views, respectively, of a turret lathe showing the tracer and pattern control of this invention applied thereto for operation at onefof the turret tooling stations.

Figure 21 is a detail sectional view on line 2l-2l of Figure v20.

Figure 22 is a sectional View to a larger scale on line 22-22 of Figure 19.

Referring first to Figures 1 to 6, there are shown a tracer and power controlling devices actuated thereby As shown the tracer comprises a casing I having a tubular portion 2' seated in a hole 3 in a valve casing 4. To the lower end of the casing I there is secured a tapered nose 5 partly closed by a cap 6 perforated at 1. Through this perforation extends loosely an end portion 8 of a tubular element 9. The .element 9 is provided with a diaphragm Ill outwardly extended therefrom and whichforms a universal pivotal connection of the element 9 with the casing I. As shown the outer margin of the diaphragm was clamped between the upperfend of the nose 5 and an internal shoulder ll of the portion 2. The member .8 which closes .oii the lower end of the element 9 is provided with a feeler element l2, which as will later appear, contacts the edge of a pattern, such a pattern being shown in Figures 8a to 150, at l5.

Within the tubular element 9,;and normally slightly spaced therefromland in parallel relation therewith, is the normally coaxially arranged element 20. This element 20 is also pivoted to the casing l as at the nose 5 by a diaphragm, this diaphragm being shown at 22 and. being pro- 3 vided with holes therethrough at 23 through which spaced segmental prongs 25 at the lower end of the element 9 loosely extend, as shown best in Figures and 6.

The lower end of the element is shown as terminating in a ball portion 26 which normally is slightly spaced from the inner conical surface 2'! of a sleeve 28 threaded into the lower ends of the prongs and held in place as by an externally threaded check nut 29. It will be noted that the pivoting diaphragm 22 for the inner member 29 is much nearer to the feeler element I2 than is the pivot diaphragm H! for the outer element 9, as shown, for example, the ratio being 1 to 10. When the element I2 is contacted on any side face against the edge of a pattern such as I5, pressure exerted against the feeler rocks the lower end of the element 9 out of its normal position about a portion of the diaphragm ID as a fulcrum, and this correspondingly rocks, but in the opposite direction, the upper end of element 9 and a flange element 30 secured thereto, part way toward the dotted line position of Figure 6. Meantime the inner element 20 remains stationary in the full line position of Figure 6. As soon, however, as the lower end of the feeler element 9 engages the lower end of the feeler element 29-, and starts to swing the element 20 about its pivot diaphragm 22, the upper end of the element 20 is swung in the same direction as was the upper end of the element 9, but at a faster rate because the lever arm of the element 20 above the diaphragm 22 is much greater than the lever arm of the outer element 9 about its fulcrum diaphragm l6. Thus by the time the

elements

9 and 30 have reached their dotted line positions of Figure 6, the element 20 has reached its dotted line position also, but because when the

elements

9 and 30 first started to move the element 20 was stationary, and thereafter the upper end of element 20 moved faster than the upper end of the element 9 and the element 30, the relative direction of motion between the upper ends of elements 20 and 39 during the motion of element 20 was reversed to such relative motion while the element 20 was stationary. This reversed direction of relative motion is employed to efiect a control of a tracer moving mechanism in a direction opposite to that produced by the first motion of the outer element 9 alone and for a purpose which will later appear.-

As shown in Figures 2 and 6, the flange member 30 has fulcrumed thereon a pair of levers 49 and' 4|. The fulcrum points are arranged 90 apart relative to the axis of the member 30. One arm 42 of the lever 49 is pivotally connected to a flex ible link 43 leading to a sliding valve member 44. The corresponding end of the lever 4| at 45 is connected by a similar link 48 to a pilot valve member 41. The opposite end of each of the levers and 4| is connected by a flexible link such as 48 extending through holes 49 in the member 9 and secured in holes in the member 28. Thus as the upper end portion of the outer or feeler element 9 is swung short of contact with the inner element 29, one or the other, or both, of the fulcra of the

levers

40 and 4| are moved in a corresponding direction which results in corresponding motions of the

pilot valves

44 and 41. As soon, however, as the innerelement 29 is contacted by the outer element and moved thereby, the inner element at its upper end moves in the same direction as did the outer element but at a faster rate, this actuating either one or both the levers 40 and in the reverse direction and l causing a corresponding reverse direction of motion of the

valves

44 or 41, or both.

Means are provided for yieldingly normally centering the

elements

9 and 29. As shown such mean comprises, besides the inherent flexibility of the diaphragms l5 and. 22, a coiled helical spring 59 (Figure 2). lhis spring is interposed between a pair of abutments El and 52 which are normally pressed in opposite directions against

annular shoulders

53 and 54 at opposite ends of a tubular casing 55. This casing 55 has an outwardly directed flange 5% between its ends, which is held against an internal annular shoulder 5'! on the casing part i by engagement therewith of an annular flange projecting inwardly from a cap iii which normally closesthe upper end of the casing i and is threaded into the upper end thereof. The casing 55 may be centered by adjusting screws E32 threaded through the casing i and engaging the outer face of the casing each of these screws being provided with a check nut 84. The abutment 5! is provided with a stem 65 having a ball end. 65 which slidably engages in a cupshaped extremity of the element 20. The abutment 52 is provided with a conical tubular stem 68 surrounding the stem 65 and with its lower end slid-ably engaging the internal wall of the element 9. As the upper end or" the element is moves laterally, its engagement with the stem causes this stem to tilt, thus compressing the spring 58 on the corresponding side, this spring then tending to press the abutment 52 against the shoulder 55- throughout its circumference and centering the til coaxially with the element 9. Similarly, lateral motion of the upper end of the element 23 causes the stem 65 to be tilted, bringing the corresponding outer edge portion of the abutment 5! away from contact with the shoulder 53, this being opposed by the righting action of the spring 50 which tends to hold the abutment 5i in engagement throughout its circumference with the shoulder 53 and with the stem 65 coaxial with the element 20. Thus the spring 5s tends to center each of the

elements

9 and 2% whenever they are displaced from normally coaxial spaced relation.

Each of the

pilot valves

44 and 41 is a spool valve having a pair of spaced annular valve close ing portions 15 and H, which, on axial motion, control communication between central and end passages 52, T3 and i i which lead to the center and end portions, respectively, of corresponding reversing valve casings 75 and control the positions in such casings of a pair of reversing valves "58 and "19. The passages 12 leading to the central portions of the pilot valves 4 1 and 4? are in communication with a fluid pressure pipe 81' which also leads to the central reduced diameter portions El of the reversing valves 18 and ill.

As shown best in Figure 3, each of these reversing spool valves is provided with tapered central extensions 85 at their opposite ends which may extend through and close correspondingly tapered openings in valve plates 86. As soon as pressure actin on the end of either of these stems from the

passages

13 and 14 causes the reversing valve to move in the 0pposite direction, the adjacent tapered end 85 opens a bleeder passage 8? through the plate 86. The plate 8-5 is provided with passages 88 leading from the bleeder passage 3'! to the adjacent end of the corresponding spool reversing valve and the pressure is equalized at opposite ends of this valve through longitudinal ports 39 through the valve. he bleeder passage 8'! at each "end of each of the reversin valves leads through Lileeder ports 99 to a discharge passage 9!. This passage also communicates with the interior of the casing l and receives fluid drain through longitudinal holes Hill of

valves

44 and 4! passing thereinto around the stems 43 and 46 of the pilot valves (see Figures 2 and 6). This construction provides for a sensitive floating aetion of the pilot valves, the central spool portion of which controls the passage of fluid under pressure from the pressure pipe 99 to either passage l3 and M to the reversing valves. A'guard 92 directs the drainings into the passage 9|.

In Figure '7 is shown diagrammatically the pressure system of which these valves form a trol of the axial positions of the reversingvalves and consequently a sensitive control of the rate of flow of: the fluid under pressure to the motor cylinders I29 and I2 I.

In Figure '7 the showing is diagrammatic, the fluid connections and valve construction having been laid out'to simplify the relation of tracer head and valves to their respective motors or power cylinders. Pressure line 89 feeds both reversing valves at 18 and i9 and pilot valves at 1 and 47. Movement of either pilot valve, or both will cause flow to end chambers encasing pistons 85 of their respective reversing valves. The small areas of pistons 85 will amplify movement of valves 18 or 79 or both for reater supply to their cylinders 29 or i2! through connections [22, i23, I2 2, !25. The connections to the discharge'pipe 9| from the pilot valves being illustrated as from theclosed ends of pilot valve cylinders and from the interior of the casing l, as also shown in Figure 3, longitudinal ports l90 tend to equalize backer drain pressure on the ends of the pilot valves. 1

The effects of motions of the

tracer elements

9 and 29 in controlling the relative motions between the tracer and pattern and the correspondon pressure rise above a desired pressure level.

The delivery from the pump passes to anaccumulator i H and opens into the valve casin N32. The valve it! is provided with two enlarged end portions H2 and H9 and is also provided with an oppositely tapered central portionlM'.

In the on position shown in Figure 7, the portion l [4 is positioned between the supply passage I 15 leading from the pump and the discharge passage H5 returning to the tank I95 through a pressure relief valve H! set to give a predetermined back pressure. In the position of the parts shown the fluid under pressure passes the valve 19! into the pressure pipe 80. On moving the control'handle H13 in clockwise direction the valve portion [is may more or less throttle the supply pipe H5 until finally it opens passage to the discharge pipe H6 whereupon pressure in the pipe 89 'is lowered to that determined by the setting of the relief valve I ll.

Pressure derived from the pipe 89 leading to the pilot valves 24 and 4'! controls the positions 'of the booster or reversing valves 79 and 18, which, in turn, control the supply and discharge from the pressure pipe 80 to opposite ends of the power cylinders I20 and IZI, the cylinder l2! having the pipes I22 and E23 leadingfrom the casing of the booster valve 18 to opposite ends thereof and the cylinder I26 having similar pipes I2 5 and I from opposite ends thereof leading to the casing for the booster valve 19. The power cylinder I29 is connected in the Well understood manner to cause longitudinal traversing motion of a slide which carries either the pattern or the tracer and the power cylinder I2! is caused to produce lateral or feeding motions of this carriage at right angles to the motion pro duced by the power cylinder I20 and the motions of this carriage are thus controlled by the relative positions of the

tracer elements

9 and 20 as the feeler i2 is brought into contact with the edge of the pattern. Figures 19 to 22 show such a mechanism as applied to a turret lathe and this will be described later.

The arrangements of the pilot and reversing valves provide for a very sensitive control of the power'cylinders. The tapered valve portions 85 of the reversing valves provide a sensitive coning relative motions between the tool and work are illustrated diagrammatically in Figures 8 to 15 and 8a to 15a. For example, Figure 8 shows diagrammatically the relative positions of the pilot valves, the tracer elements, and their con-' nections when the feeler 9 is brought against the edgeof the pattern 55 in the position shown in Figure 8a. It will be noted here that the i lower end of the element 9 carrying the feeler is pressed against a straight edge portion-of the pattern 15 and in a direction such that the feeler is displaced forwardly while the upper end of the element '9 is pushed upwardly out of concentric relation to the element 29 as shown in Figure 8. This positions the pilot valves ll and 44 in such a manner as to admit pressure to move the tracer along the pattern to the left and to press the tracer backwardly against the edge of the pattern in the direction shown by the arrows of Figure 8a. Continued pressure of the element 9 toward the edge of the pattern causes the element 9 to engage the element 20 and move 'it therewith. This causes the upper end of the element 29 to be moved backwardly faster than the element 9 to the position shown in Figure 9a, which results in rocking the lever 49 in a direction to cause reversal of the flow through the pilot valve 4:3 while the flow continues in the same direction through valve 41 as shown by the arrows in Figure 9a This results in reversing the direction of motion of the longitudinal motor H9, thus moving the tracer as a unit away from the pattern edge, while continuing its motion crosswise in the direction shown by the arrows in Figure 9a, though the 'feeler remains in contact with the pattern edge.

This returns the parts toward the condition of Figures 8 and 8a, except for the progress of the tracer to the leftwhich has been going on steadily. When this condition is again reestablished, the direction of motion of the longitudinal slideis again reversed (see Figures 8 and 8a) and feeds toward the edge of the pattern. This condition of oscillation of. the tracer toward and from the edge of the pattern While the feeler maintains'contact therewith, and is being traversed therealong, continues until the tracer contacts with the edge of the pattern at what is commonly termed a critical angle where its direction is being changed as shown in Figure a. Since at that point the traverse motion, as well as the feed motion, presses the feeler against the pattern, the element 9 is offset by such contact relative to the element 20in an angular direction, which moves the valve 41 in a direction to increase the feed to the left and to move the valve 44 to feed rearwardly as shown by the arrows in Figure 10a. This angular displacement of the tracer causes contact of the element 9 against the element 20 in the same direction as shown in Figure 10a which relatively displaces the upper ends of the

elements

9 and 20 as shown in Figure 11. This not only causes reversal of flow through the valve 44, but also a slower reversal through valve 41, resulting in motion of the tracer both forwardly and to the right as shown by the arrows of Figure 11a, and this action takes place while the tracer parts again approach the conditions of Figures 10 and 10a. as when feed of the tracer toward the pattern edge is reestablished. As the tracer continues to pass around the end portion of the pattern as in Figures 12 and 12a, the

tracer elements

9 and 20 take successively the positions of Figures 12, 12a to 13 and 13a, rapidly alternating the directions of motion of the cross slide while the longitudinal slide continues to move forwardly as shown by the arrows in Figures 12a and 13a, which illustrate by their respective lengths the relative speeds of the forces applied.

As the tracer proceeds with its feeler in contact with the pattern, the tracer mechanism moves from the position shown in Figures 12a and 13a toward the position shown in Figures 14a and 15a. It will be noted that now the feeler is engaging the front edge of the pattern rather than the back edge as it was doing in Figures 8a and 9a, consequently the lower end of the feeler is being pressed backwardly from its normal position instead of forwardly as in the positions of Figures 8, 8a, 9 and 9a. When the feeler is displaced to an extent short of engagement of the element 9 with the element 20, as is shown in Figures 14 and 14a, the upper end of the element 9 carrying the flange 30 is displaced forwardly relative to the center of the upper end of the element 30, this being in the opposite direction to the showing of Figure 8. This causes the

valves

44 and 41 to take the position shown in Figure 14, reversing the direction of flow through both of these valves and so reversing the direction of motion of the traverse and feed motors so that the tracer is then moved along the front edge of the pattern opening to the right, which is in the opposite direction to the movement shown in Figures 8a and 9a when the tracer traverse motor is moving the tracer to the left. There is also a small component of motion pressing the tracer forwardly to press its feeler against the pattern edge, the relation and relative magnitudes of these forces being shown by the arrows in Figure 14, which it will be noted are opposite to the forces shown in Figure 8a. This motion of the tracer forwardly takes place until after the lower end of the element 9 has contacted and moved the lower end of the element 20, whereupon the upper end of the element 29 moves faster than the upper end of the element 9 and in the same direction so that the parts take the position shown in Figures 15 and 150.. In this position of the parts, it will be noted that the valve 44 has been reversed from the position shown in Figure 14, while the valve 41 remains in the same position, and still allows fluid to flow in the same direction as the arrow indicates in Figure 14. This causes the traverse of the tracer mechanism to continue but reverses the feed direction so as to move the tracer backwardly toward the relationship between the

elements

9 and 20 shown in Figure 14a, reversing the direction of the feed motor while continuing the traverse to the right. When the parts have returned to the position shown in Figures 14 and 14a, the tracer with its feeler is fed against the work edge toward the position of Figures 15 and 1511. Thus the feed motion is alternately reversed while the traverse motion continues in the same direction to the right, thus returning the tracer toward the right hand end of the pattern where if the pattern is continuous, the tracer is then caused to trace the edge of the pattern until it again reaches its back edge, whereupon the conditions of Figures 8 and 9 are again resumed. The action of the motors in returning the tracer to the back edge of the pattern follows the course but in the reverse direction in so far as the traverse is concerned of Figures 10 and 10a to 13 and 13a, as may be understood b reference to these figures. Thus when the tracer is presented to the pattern, it automatically follows completely around the contour thereof and automatically repeats until stopped, producing the required controls of the traverse and feed motors to produce this result with alternate feeds against the pattern edge and then away therefrom minute in amount, but having the effect of keeping the feeler against the pattern edge and causing it to move therearound.

From the foregoing it will be seen that the tracer is moved uniformly along the pattern with a rapid in and out motion against the edge of the pattern, but of very small amplitude, the feeler remaining in contact therewith and that when the tracer has once been pressed against the edge of the pattern, the motor mechanisms are from there automatically controlled to cause the feeler to move along and around the edge of the pattern.

This complete closed tracing circuit is provided automatically without requiring any turning of the tracer mechanism as has heretofore been necessary when moving through more than one quadrant of a complete circuit, and a complete circumference of the feeler operatively engages the pattern during this circuit.

It will be noted that the displacement of the feeler with relation to said support is in any direction in a plane and such displacement in any direction is effective in controlling the feed mechanism.

In Figures 16 and 17, a modification has been illustrated in which the initial controls from the

tracer elements

9 and 20 are electrical. Referring to these figures, the stems 43 and 46 instead of being connected to pilot valves are connected to resilient switch arms I50 and I5I having oppositely disposed contacts I52 and I53 adjacent to their free ends. These contacts are movable back and forth between contacts I54, I55 and I56, I51, these latter being carried by pivoted arms I58, each being adjustably secured to a supporting plate I by screw and slot connections at I6I. In order to prevent sticking of the contacts and to maintain the switch mechanism, including these contacts, in a sensitive state, the foundation plate I69 is shown as fulcrumed on a pivot I and it is provided with a slot IE6 within which is mounted an accentric pin I6! carried by the shaft I68 of a small motor I69. This motor has aseaesa connected thereto leads I10 and HI from a suitable source of power by which the motor may be driven, thus this, through the action of its eccentric pin I61, oscillating the plate I69 rapidly through a very small are. As the

levers

40 and 4| are rocked by motion of the tracer element 9 and relative motions between this element 9 and the element 20, contacts are made between the movable contact elements I52 and I53 and their adjacent elements I56, I55 or I56, I51, thus -completing electric circuits through solenoids I 86, I8 I I82 and I83 which rock the T-shaped levers I 84 and I85 connected through links I36 and I8! with the controlling valves 588 and I89, which, in turn, control fluid under pressure to the longitudinal slide motors I26 and the cross lide motor I2I. The amplitude of motion of the T-shaped levers I84 and H35 is limited by contact with opposite sides of notches H95 and I95 of angularly adjustable limit plates 19'? and I 93. The action of this mechanism is substantially the same as heretofore described so that no further description appears to be here necessary.

In Figure 18 a further modification is shown of hydraulic actuation. Referring to thi figure, a different form of hydraulic valve from that shown in Figures 1 to 15, is illustrated, together with different connections to the inner and outer tracer elements 26 and 9. Between the pilot valve 2M! and its ported valve casing 2c: is a sleeve 202. This sleeve has an extension 2613 which i connected through a link 2% to a post 265 secured to the table or flange the which is carried by the upper end of the outer tracer element 9. The

valve 2% isconnected through a link 2H1 with the upper end portion of the tracer element 20, passing looselythrough a hole 2! I through the upper end portion of the tracer element 9. It is understood that there are two of these valves 26!) with their sleeves 282 arranged at right angles to each other and taking the places of the pilot valves 44 and ll of the constructions previously described, the valve and its sleeve corresponding in position to the valve 44 controllin the front and back feed motor i2l shown in Figure 7, and the pilot valve 209 with its parts corresponding in position to the pilot valve 41 of Figure 7,.controlling the longitudinal slide motor 29. The sleeve 202 has ports 2i5, 2E6 and 2 H which serve as extensions of the main valve casing ports 2E8, 2|9 and 229, respectively, which correspond to the one end, the central, and the other end ports of the spool valve shown in Figures 1. to 15, but the effective positions of these port 2 l8, 2I9 and 22B is changed lengthwise of the valve cylinder by axial motion of the sleeve 283, thus to correspondingly change the efieotive position of the valve 200 with reference to the main valve ports 2E8, ZIQ and 220. The arrangement is such that the valve 2% is effective to change the supply and discharge to the feed and traverse motors corresponding thereto partl in accordance with the position or" the valve 28% and partly in accordance with the position of the sleeve 202, and the combined eiiects of the sleeve and valve to control the directions of motion of the feed and traverse or the cross and longitudinal slides, is identical with that produced by the single valve arrangement operated by the composite motions of the flange or table 353 and the inner tracer element 22 a previously described. I

In Figures 1i) to 22, inclusive, the application of a pattern and tracer as previously described is shown to a turret lathe to control the operation of the tool at oneof the tooling stations of 10 the turret. As shown in these figures, the lathe comprises the bed 390 having the usual headstock 3t carrying the rotating spindle provided with a chuck 38 2 for supporting the work piece 393. At 3&4 is shown the usual longitudinally slidable carriage on which is supported the cross feed slide 3&5 mounted for front and back feed motion, this feed slide supporting the 'indexable turret 396 of conventional type, as shown there being six turret faces, each carrying one or more tools. One of these tools at 30'! is to be controlled by the pattern and tracer mechanism. The tracer mechanism is shown as extended upwardly coaxial with the turret and including the tracer head 33% pivoted at the top of the turret by a flange 33? (Figure 20) axially fixed to tracer head 383 and encased in member 359 fixed to the turret. At 32!} is shown a tank support at the tail end of the machine in which is mounted the hydraulic longitudinal slide actuating motor I2?! provided with a piston 315 which may be secured to the back portion of the traversing carriage 394. At 3H5 (see Figure 19) is shown a rotary reversible hydraulic motor which takes the place of the reciprocating motor l2l of Figure 7 and is arranged to operate the cross slide ieeding mechanism, to this end being adapted to rotate a feed screw 3H. At 329 is illustrated the conventional carriage traverse wheel by the rotation of which the carriage 3% may be given its hand actuated traverse. A rockable handle 32! may be provided by the rocking of which any suitable power traversing mechanism may be thrown into or out of controlling relation to drive the carriage 39 3. This is old and well known in the art, but may be, if desired, oi the construction shown in Figure 9 or" the Lovely Patent No. 2,066,144 granted June 25, 1935. This power traverse mechanism may be employed during the operation at the other tooling stations of the turret, but is thrown out when the controls by the pattern and tracer are to be brought into operation.

The support 3m is shown as connected to the headstock by a bar 325 on which is rockably mounted between a pair of adjustable collars 328 and 32? clamped to the bar 325, a pattern holder 328. This may be turned upwardly about the bar 325 as an axis into the inoperative position shown in Figure 20 and in full lines in Figure 21, and there held by a latch 3 i 3, or it maybe rocked down to horizontal position shown in dotted lines in Figure 21 in operative relation to the upwardly projecting tracer head 3M3. The pattern holder 323fcarries the pattern 322 which may be adjustable toward and from the axis or" the part 325 as by manipulation of the adjusting screw 339. By this means the edge of the pattern opening 335 may be brought into such relation to the ieeler as to cause the valves controlled by the feeler to operate to produce the desired tracing action of the tracer along the pattern edge as previously described.

At 346 on Figures 19 and 20 is shown a motor having a fluid pump 345 actuated thereby which supplies the fluid under pressure from a suitable source to the tracer controlled valve mechanisms through the pressure pipe 3% which leads to the distribution box 3 53. This box contains the controlling valves fer the feed and traverse motors which are connected through suitable connections housed within the tube 3% to the mechanism housed within the tracer head 3%. The tube 3M supporting the box 343 is slidable through the vertically pivoted guide sleeve 335. From the distribution head 343 pipes extend to a valve caslli ing 345 from which extend a pair of flexible pipes 345 and 341 to opposite sides of the feed motor 315 and a pair of

flexible pipes

343 and 349 to opposite ends of the traverse motor 120. A discharge pipe 35!] leads from the distributing chamber 343 back to discharge. In this embodiment of the invention the

pipes

342, 350, 346, 341, 348 and 349 perform the functions of the pipes 38, 9|, I22, I23, l24 and I25, respec tively, of the diagrammatic showings of Figures 1 and 7 and are connected into the various parts in the same manner, the

valve mechanisms

44, 4?, l8 and 79 forming part of the tracer mechanism and being carried by the turret.

Ihe valve 343, as shown in Figure 22, has a valve plug 355 having suitable ports 356 and 35'! which may be brought in registry with the pairs of pipes 348 and 34'! and 348 and 359, respectively, in order that when the tracer mechanism is not employed, as when tools of the other tooling stations are to be operated, opposite sides of each of these motors 318 and Hi] may be connected together so that the carriage 304 and cross slide 305 may be moved freely without interference from these motors. When the tooling station of the turret where control of the tool from the pattern is desired, the tool is brought into proper angular position to operate on the work, the valve plug 355 is turned toopen the ports of pipes 3&8 and 341, 348 and 369 and to connect them into the distributing chamber 3 53. The motors me and 316 are then under control of the valves actuated by the tracer. The pattern is swung down into operative relation to the tracer which has been moved into position to cooperate therewith, whereupon the turret tool is under the full control of the tracer mechanism and cuts the work in accordance with the pattern and repeats so long as the pattern is in position for the tracer feeler to bear against its edge and the power supply is in operation.

From the foregoing description of certain embodiments of this invention and applications thereof to a machine tool, it should be evident to those skilled in the art that various other changes and modifications might be made without departing from the spirit or scope of this invention.

I claim:

1. In combination, a tracer comprising a pair of normally parallel slightly spaced elements, one of said elements having a feeler, of ,a, support to which said elements are pivoted for lateral motion, the pivot for said feeler element being spaced from said feeler further than the pivot for the other of said elements, whereby motion of said feeler in a direction to contact said other element thereafter moves said other element therewith and remote from said feeler at a faster rate, a control member carried by said support,

operative connections from said elements to said member, and power means for moving said tracer controlled by said control member.

2. In combination, a tracer comprising a pair of normally parallel slightly spaced elements, one of said elements having a feeler, a support to which said elements are pivoted for lateral motion, the pivot for said feeler element being spaced from said feeler further than the pivot for the other of said elements, whereby motion of said feeler in a direction to contact said other element thereafter moves said other element therewith and remote from said feeler at a faster rate, a control member carried by said support, an operative connection from said feeler element to said control member, and a connection from said other element to said operative connections for modifying the control effected by motion of said feeler element.

3. A tracer comprising a support, a pair of normally coaxial elements, the outer of said elements having a pattern feeler at one end and being pivoted for universal swinging motion to said support, the inner of said elements having an end positioned adjacent to said feeler normally slightly spaced from said feeler element but adapted to be contacted thereby and moved on motion of said feeler element out of normal angular position, said other element being universally pivoted to said support nearer to said feeler than is said feeler element, yielding means tending to hold said elements in normal coaxial relation, a flange member secured to said feeler element on the opposite side of its pivot from said feeler, a pair of levers fulcrumed on said flange member at points spaced angularly about its axis, a pair of radially arranged control devices carried by said support corresponding to the angular spacing of said levers, a connection from one of each lever to the correspondingly positioned control device, and a connection from the inner end of each lever to said other element, whereby the angular position of said feeler element relative to said support modified by the angular position of said inner element relative to said support controls said devices.

4. A tracer comprising a support, a pair of normally coaxial elements, the outer of said elements having a pattern feeler at one end and being pivoted for universal swinging motion to said support, the inner of said elements having an end positioned adjacent to said feeler normally slightly spaced from said feeler element but adapted to be contacted thereby and moved on motion of said feeler element out of normal angular position, said other element being umversally pivoted to said support nearer to said feeler than is said feeler element, yielding means tending to hold said elements in normal coaxial relation, a pair of valve mechanisms angularly spaced apart about the normal axis of said elements each of said valve mechanisms comprising a ported casing, a sleeve fitting within said casing for axial motion relative thereto and having ports communicating with the several casing ports throughout the sliding range of said sleeve, a valve slidable Within said sleeve and having ports for selective connection with said sleeve ports, connections between one of said elements and said sleeve and between the other of said elements and said valves, and angularly disposed power-moving means controlled by the relative axial positions of said valves and their respective sleeves.

5. A tracer comprising a support, a pair of normally coaxial elements one within the other and normally slightly spaced apart, the outer of said elements having a feeler at one end, said feeler element being pivoted to said support spaced from said feeler, the inner element being pivoted to said support nearer to said feeler than is said feeler element, a tubular casing carried by said support, a pair of spaced abutments in said casing, said casing having annular shoulders against which said abutments may engage, a spring between said abutments tending to hold said abutments against said shoulders, stems projecting from said abutments and engaging said elements and yieldingly holding said elements in coaxial relation, control devices carried by said support,

13 and operative connections between said devices and said elements.

6'. In combination, a tracer comprising a pair of normally parallel slightly spaced elements, one of said elements having a feeler, a support to which said elements are pivoted for lateral motion, the pivot for said feeler element being spaced from said feeler further than the pivot for the other of said elements, whereby motion of said feeler in a direction'to contact said other element thereafter moves said other element therewith and remote from said feeler at a faster rate, a pair of relatively angularly arranged pilot valves carried by said support, an operative con nection from said feeler element to each of said pilot valves, a connection from the other of said elements to each of said operative connections for modifying the effects on said pilot valves of the motion of said feeler element, angularly related direction moving: means for said tracer including a pair of reversible hydraulic motors, and a pair of reversing valves controlled by said pilot valves for controlling said hydraulic motors.

7. In combination, a tracer comprising a pair of normally parallel slightly spaced elements, one of said elements having a feeler, a support to which said elements are pivoted for lateral motion, the pivot for said feeler element being spaced from said feeler further than the pivot for the other of said elements, whereby motion of said feeler in a direction to contact said other element thereafter moves said other element therewith and remote from said feeler at a faster rate, an electrical circuit control member carried by said support, an operative connection from said feeler element to said control member, a connection from said other element to said operative connection for modifying the control effected by motion of said feeler element, power means for moving said tracer, and a control for said power means including an electric circuit controlled by said control member.

8. A tracer comprising a support, a pair of normally coaxial elements, the outer of said elements having a pattern feeler at one end and being pivoted for universal swinging motion to said support, the inner of said elements having an end positioned adjacent to said feeler and normally slightly spaced from said outer element but adapted to be contacted thereby and moved on motion of said outer element to a sufficient extent out of normal angular position, said inner element being universally pivoted to said support nearer to said feeler than is said outer element, a control member, and operative connections from both of said elements and spaced from their pivots to said control member.

9. A tracer comprising a support, a pair of normally coaxial elements, the outer of said elements having a pattern feeler at one end and being pivoted for universal swinging motion to said support, the inner of said elements having an end positioned adjacent to said feeler and normally slightly spaced from said outer element but adapted to be contacted thereby and moved on motion of said outer element to a sufiicient extent out of normal angular position, spring means engaging said elements and tending to hold said elements coaxial and to return them to coaxial relation when displaced therefrom, said inner element being universally pivoted to said support nearer to said feeler than is said outer element, a control member, and operative connections from both of said elements and spaced from their pivots to said control member.

10. In combination with a feeler, power means for moving said feeler in either direction in two angularly related paths, a pair of relatively movable elements operatively connected to said feeler and to each other to be moved relatively in one direction during a predetermined extent of feeler motion from a predetermined position in directions corresponding to each of said paths and in the opposite direction and at a different rate during a further motion of said feeler in the same direction in excess of said extent, and a control for each of said feeler moving means responsive in its control direction to the relative positions of said elements.

WILLIAM L. TANCRED.

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

UNITED STATES PATENTS Number Name Date 1,381,752 Scheyer June 14, 1921 1,588,856 Shaw June 15, 1926 1,677,131 Cole et a1 July 17, 1928 1,952,230 Anderson Mar. 27, 1934 2,036,362 Sassen et a1. Apr. 7, 1936 2,047,181 Ferris July 14, 1936 2,199,465 Martellotti May 7, 1940 2,226,677 Vikham Dec. 31, 1940 2,263,764 Elberty Nov. 25, 1941 2,331,337 Meyer Oct. 12, 1943 2,331,817 Turchan et al Oct. 12, 1943 2,334,956 Ridgway Nov. 23, 1943 2,345,218 Rosen Mar. 28, 1944 2,372,426 Johnson Mar. 27, 1945 2,372,604 Rosen Mar. 27, 1945 2,389,426 Turchan Nov. 27, 1945 2,409,903 Schwartz Oct. 22, 1946 2,436,373 Barnes Feb. 24, 1948 ertificate of Correction Patent N0. 2,562,284 July 31, 1951 WILLIAM L. TANCRED' It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 12, line 25, after one insert end; line 27, for inner read other; same line, for other read inner;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 9th day of October, A. D. 1951.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents.