US3217567A - Horizontal boring mill - Google Patents

Description

Nov. 16, 1965 E. P. BULLARD m, ETAL 3,217,567

HORIZONTAL BORING MILL Filed Aug. l0, 1961 8 Sheets-Sheet 1 NOV- 16, 1965 E. P. BULLARD m, ETAL 3,217,557

HORIZONTAL BORING MILL Filed Aug. l0, 1961 8 Sheets-Sheet 2 I'n n n 58| INVENTORS.

EDWARD P.BULLARD III F' G 2 BYEDWARD P. BULLARD II TTORNEY NOV- 15, 1965 E. P. BULLARD lu, ETAL 3,217,567?v HORIZONTAL BORING MILL 8 Sheets-Sheet 4 Filed Aug. l0, 1961 INVENTORS. EDWARD P. BULLARD III BY EDWARD P. BULLARD E ATTORNEY NOV 16, 1965 E. P. BULLARD m, ETAL 322379557 HORI ZONTAL BORING MILL Filed Aug. l0, 1961 8 Sheets-Sheet 5 evs eve avv 67e eso lI n1/`e75 697 voe 694/703 FIG.6 7

679 677 RANGE! l j J SPEED 6 SELECTIONS INVENTORS. EDWARD P. BULLARD IDI EDWARD P. BULLARD E Newo 16, 1965 E. P. BULLARD im, ETAL 32H56? HORIZONTAL BORING MLL Filed Aug. l0. 1961 8 Sheets-Sheet 6 l l 905 5 y; 906

908 909 745 755 a M me l D T56 900 l l 902 900 :,52`/ 74| =7oe\` #853 -e29 902 91| 767 907 B57' ^9x2 902 747 74o eoa'rq-g '/rg 65 773 86o 9oz 9,4 775 909 \915 767 768 774 B53. 838 aas 76o 76e 772 85p IH/ 902 759 ll/ 839 B49. E t 848' lli l i e 946 944 965 ses ses' 942 867 INVENToRs. Fl G 9 EDWARD P. BULLARD III.

EDWARD P. BULLARD N Nov. 16, 1965 E. P. BULLARD m, ETAL HORIZONTAL BORING MILL 8 Sheets-Sheet 7 Filed Aug. l0. 1961 INVENTORS. EDWARD P. BULILARD IUI EDWARD P. BULLARD E Nov. 16, 1965 E. P. BULLARD m, ETAL 3,217,557

HORIZONTAL BORING MILL FIG.2I

INVENTORS. EDWARD PULLAFD III BY EDWARD P.BULL.AF1D E (mW/QZ ATTORNEY United States Patent O 3,217,567 HRIZONTAL BDRING MILL Edward P. Bullard III and Edward I. Bullard IV, Fairtield, Conn., assignors to The Billiard Company, Bridgeport, Coun., a corporation of Connecticut Filed Aug. 10, 1961, Ser. No. 130,598 7 Claims. (Cl. 77-3) The present invention relates to machine tools and particularly to a new and improved horizontal boring, drilling and milling machine.

An object of the invention is to provide a horizontal boring, drilling and milling machine that will require a minimum of mental and physical exertion to operate it.

Another object of the invention is to provide such a machine tool in which all motions of the various movai'ble members are controlled from a single pendant control.

Still another object of the invention is to provide such a machine tool in which no handwheels or levers are required to be manually operated to control the operation ofthe machine tool.

Still another object of the inventon is to provide such a horizontal boring rnilfl in which infinitely variable feed rates in inches per minute and inches per revolution are provided for all of the movable members of the boring mill.

Still another object of the invention is to provide such a horizontal boring mill having a twenty-eight speed headstock that is of compact design.

Another object of the invention is to provide such a horizontal boring mill in which lthe spindle is axially moved by mechanism that exerts equal forces on diametrically opposite sides thereof.

Still another object of the invention is to provide such a horizontal boring mill in which the pendant control can be held in one hand and the movements of all of the movable members of the boring mill can be effected by two ngers of the hand holding the pendant.

The above, other objects and novel features of the invention will become apparent from the following specification and accompanying drawings which are merely exemplary.

In the drawings:

FIG. 1 is an elevational view of certain parts of a horizontal boring mill to which the principles of the invention have been applied;

FIG. 2 is a stretch-out view of certain gearing arrangement within the clutch case C of FIG. l

FIG. 3 is a sectional elevational view of the headstock transmission within the head H of FIG. 1;

FIG. 3A is a diagram of the epicyclic 4gearing arrangement C of FIG. 3;

FIG. 4 is a sectional elevational view taken substantially along line 4-4 of FIG. 3;

FIG. 5 is a sectional elevational View through the brake B of FIG. 1;

FIG. 6 is a view of certain control elements for shifting the clutches within the headstock of FIG. 3;

FIG. 7 is a sectional view taken substantially along line 7 7 of FIG. 6;

FIG. 8 is a developed View of the cams forming the control of FIG. 6;

FIG. 9 is a schematic showing of the various elements of the VS unit of FIG. 1;

FIG. l0 is an end view of the pendant control;

FIG. 11 is a view of the control of FIG. l0 as seen from one side thereof, parts being broken away to show others;

FIG. 12 is a view of the control as seen from another side with parts broken away to show others;

i 3,217,567 Patented Nov. 16, 1965 FIG. 13 is an exploded view of certain of the parts Within the control pendant of FIG. l0;

FIG. 14 is a view of the direction selecting mechanism of the control of FIG. l0;

FIG. 15 is a sectional View taken substantially along line 15-15 of FIG. 14;

FIG. 16 is a view of an interlocking plate used in the control of FIG. l0;

FIG. 17 is a View taken substantially along line 17-17 of FIG. 15;

FIG. 18 is a view taken substantially along line 18-13 of FIG. 15;

FIG. 19 is a sectional View taken along line 19-19 of FIG. 18; and

FIGS. 20 and 2l are wirin g diagrams.

The principles of the invention are shown as applied to a horizontal boring mill in which there `are shown only those elements that are necessary to an understanding of the invention. A head H may lbe supported for vertical movement, and it includes a spindle S adapted to be rotated at any one of a large number of speeds, as well as to be moved axially outwardly toward a rear spindle support R that moves vertically with the head H. Between the head H and the rear spindle support R is mounted a saddle S for longituidnal movement leftwardly, as viewed in FIG. 1, toward the rear spindle support R, and right- Wardly toward the head H. The saddle S is provided with ways on which is mounted a work supporting table T which latter is adapted to be reciprocated at right angles to the path of movement of the saddle S A clutch case C may include a transmission for effecting the various movements of the movable members of the machine tool` including movement of the head H, the rear spindle support R, the saddle S and the work supporting table T, as Well as for effecting the axial feeds of the spindle S. A variable speed feedworks transmission VS is mounted at the side of the clutch case C to provide feed and traverse rates of movement to the movable members of the machine.

A trigger-like pendant P, mounted in cooperating position relative t-o the work supporting table T, is provided with a plurality of switches which control the operation of solenoids for the clutch case C, the clutch and brake unit B, as well as switches for the control of the feed rates of the movable members. Movement of a triggerlike element of the pendant P in one direction from a neutral postion causes the movable members to move at a preselected feed rate, and movement of the trigger-like element of the pendant P to -a plurality of positions on the other side of the neutral position causes control of the rate of traverse motion of the movable members.

The upward and downward movements 1of the head H and the rear spindle support R are caused by a pair of bevel gears Stlt) and 506 that transmit rotative power from the clutch case C to the threaded shaft 504 and to the splined shaft Sill through gears 502 and 503. The threaded shaft 504 threadingly engages a nut member 505 that is fixed to the head H. The splined shaft 501 supports a bevel gear 507 that transmits power to a bevel gear 508 fixe-d to a threaded shaft 509 that extends vertically through the rear spindle support R. The threaded shaft 509 threadingly engages a nut member 510 that is fixed to the rear spindle support R. Accordingly, the head H and the rear spindle support R will move in the same direction at the same rate of travel when shaft 511 is rotated.

Referring to FIG. 2, gear S03 and bevel gear 506 are fixed to shaft 511 which may support two gears 513 and 514 for free rotation. A fluid-operated clutch 515 in clutch case C may be located between gears 513 and 514 to selectively connect either gear to shaft 511. Gear 513 meshes with gear 516 fixed to a shaft 512, causing gear 513 to rotate in one direction when power is supplied to shaft 512. Gear 514 rotates in the opposite direction through gears 517 and 518 fixed to shaft 51'9, and through gear 520 fixed to shaft 512.

Referring to FIGS. l and 3, the head H is adapted to support the spindle S, whi-ch latter comprises a rotatable and axially movable shaft 521. The shaft 521 is keyed to a hollow shaft 522 that is mounted within the head H. Axial feed movement of the shaft 521 is effective through a gear and rack construction 523. Referring to FIGS. 3 and 4, a non-rotatable housing 524 supports the tail end of the shaft 521 for rotation within antifriction bearings 525 and 526. Racks 527 and 528 are fixed to a housing 531 of head H that supports the nonrotatable housing 524 for axial movement with shaft 521. Gibs 529 and 530 acting between the housing 524 and the racks 527 and 528 ensure stability of the housing 524 during its axial reciprocation. Rack 527 meshes with a spur gear 532 fixed to a shaft 533. Shaft 533 is journaled in housing 524, one end of said shaft being xed to a gear 534 which meshes with a gear 535. Gear 535 is fixed to a shaft 537 which in turn is connected through a gear 536 to rack 528. Gear 535 also meshes with a gear 538 (FIG. 3) fixed to a shaft 538. Shaft 538 has one end fixed to bevel gear 542 that meshes with a corresponding bevel gear 540 on -a splined shaft 541. Splined shaft 541 is connected to the output shaft 543 of the clutch case C (FIG. 2) through a worm wheel 544 that meshes with worm 545 on cross shaft 546. Cross shaft 546 includes a bevel pinion gear 547 that meshes with corresponding bevel gear 548 mounted on a vertically disposed splined shaft 549, to the bottom of which a bevel gear 550 is fixed which latter meshes with a bevel pinion 551 fixed to shaft 543.

Reverse rotation of shaft 543 may Ibe effected by a reversing clutch including two gears 552 and 553 that freely rotate on shaft 543. A fiud-operated clutch 554, in clutch case C, may be located between gears 552 and `553 to selectively connect either gear to shaft 543. Gear 552 meshes with a gear 555 xed to the input shaft 512 lof the clutch case C, and gear 553 meshes with a gear `556 fixed to shaft 519 that rotates oppositely to shaft 512. From the foregoing it is evident that selective operation of clutch 554 will cause reciprocation of non-rotatable housing 524 (FIG. 3) and with it, spindle S; and will apply to housing 524 an equal force on each side thereof so as to produce a non-binding reciprocating action.

Referring again to FIGS. l and 2, the work supporting table T comprises a casting 557 that is suitably ribbed and cored to provide a rigid work supporting table for the horizontal `boring mill. The table T is provided with way surfaces adapted to ride along ways 558 and 559 (FIG. 1) of the saddle S.

Reciprocative movement of the table T relative to the longitudinal movement of the saddle S is adapted to be effected by the rotation of a nut 560 threaded on a shaft 561 that is non-rotatably supported by brackets 562 at the extremities of the table T. A rotatable bevel gear 563 is fixed to the nut element 560 and it meshes with a bevel pinion 564 fixed to one end of a stub shaft 565. The opposite end of the stub shaft 565 is connected to a splined shaft 566 through a pair of bevel pinions 568. Accordingly, rotation of the splined shaft 566 in opposite dlrections will effect the reciprocation of the table T along the ways 558 and 559 on saddle S'.

Splined shaft 566 may support two gears 567 and 568 (FIG. 2) for free rotation. A Huid-operated clutch 569, in clutch case C, may be located between gears 567 and 568 to selectively connect either gear to shaft 566. Gear 567 meshes with gear 570 fixed to a shaft 571. Shaft 571 is fixed to spur gear 572 which meshes with a gear 573 on input shaft 512 of the clutch case C. Spur gear 568 meshes with a gear 574 on shaft 575 which fixedly supports gear 576. Gear 576 meshes with gear 577 fixed to d shaft 571. Accordingly, selective operation of clutch 569 causes splined shaft 566 to rotate in opposite directions.

The saddle S is adapted to be reciprocated longitu-dinally along splined shaft 566 by the opposite rotation of a screw 578 that is threaded into a non-rotatable nut 578 fixed in saddle S. The screw 578 extends throughout the longitudinal extent of a main bed (not shown). Screw 578 may support two gears 579 and 580 for free rotation. A fluid-operated clutch 581, in clutch case C, may `be located between gears 579 and 580 to selectively connect either gear to screw 573. Gear 579 meshes with a gear 582 on shaft 571 which is connected to shaft 512 through gears 572 and 573. Gear 560 meshes with gear 583 fixed to shaft 575 which in turn is connected to shaft 512 through gears 576, 577, 572 and 573. From the foregoing it is evident that selective operation of clutch 581 causes movement of saddle S in opposite directions along the splined shaft 566.

It is apparent that shaft 511 is connected to clutch 515; shaft 543 is connected to clutch 554; splined shaft 566 is connected to clutch 569; and screw 578 is connected to clutch 581 for respectively effecting the movement of the head H and rear support spindle R; the spindle S; the table T; and the saddle S. It is also evident that clutches 515, 554, 569 and 581 are connected to the input shaft 512 of the clutch case C. The shaft 512 is connected to the variable speed feedwork transmission VS that will be described later.

Referring to FIGS. l and 3, power to move all of the movable parts of the machine tool is supplied from a headstock HS located in the head I-I. The headstock HS includes an input shaft 584, to the one end of which is connected a bevel gear `505 that meshes With a corresponding bevel gear 586 splined to a vertically disposed shaft 587. At the bottom of the vertically disposed splined shaft 587, bevel gear `588 (FIGS. 1 and 5) transmits the rotation of either bevel gear `589 on shaft 590 or bevel gear 591 on shaft 592. Shaft 590 is connected to shaft '593 through brake casting `5941 and clutch 595. Clutch 595 comprises a series of geared friction plates 596 meshing twith an internal spur gear 597 on brake casting 594, and an alternate ser-ies of geared friction plates `599 meshing with spur gear 600 on shaft 593. When pressure is applied to a piston 601 through line 602, geared friction plates '595 and 599 are compressed between slidable member 603 and fixed member 604, causing shaft 590 to rotate with shaft 593. Shaft 592 is connected to shaft 593 through casting 605 having a clutch 606. Clutch 606 comprises a series of geared friction plates 607 meshing with an internal spur gear 608 on casting 605, and an alternate series of geared friction plates 609 meshing with spur gear :610 on shaft 593. When pressure is applied to a piston `611 through line 612, geared friction plates 607 and 609 are compressed between a slidable member 6113 and a fixed member 614, causing shaft 592 to rotate with shaft 593.

A brake shoe `615 on brake casting 594 cooperates with brake band 616 and is rendered effective when pressure is applied to a piston 617 through line 618. It is evident that splined shaft 587 can 'be rotated in opposite directions by the selective action of clutches 595 and 606, and can be stopped by the application of brake 615, 616.

Referring again to FIG. 3, the end of the shaft 584 of headstock HS opposite that supporting bevel .gear 58S has `fixed to it a pair of spur . gears 619 and 620. Gears 619 and 620 mesh with corresponding gears 621 and 622 journaled and axially slidable on a shaft 623. A gear 6124 fixed to shaft 623 'between gears 621 and 622 is adapted to cooperate with internal gear 624 on gear 621 or with internal gear 625 on gear 622. One end of shaft i623 has fixed to it a pair of spur gears 626 and 6127. Gears 626 and 627 mesh with corresponding gears 628 and 629 journaled and axially slidable on shaft 584. A gear 630 fixed to shaft 584; between gears 628 and 629 is adapted to cooperate with internal gear 631 on gear 628 or with internal gear 632 on gear 629. This arrangement provides four ratios at which shaft v584 can drive shaft 623 by the selective shifting of clutches 633 and 634.

The end of the shaft 623 opposite that supporting the pair of spur gears 626 and 627 has fixed to it a sun gear 635, the tirst element of an epicyclic gearing arrangement A. Sun gear 635 meshes with planetary gears 636 fixed to shafts 637 (only one being shown). Shafts 637 are journaled in an arm 638, comprising the second element `639 of the epicyclic gearing arrangement A'. Shafts 6317 also have fixed to them planetary gears 640. Planetary gears 640 mesh with a gear 641 fixed to one end of a hollow shaft 642, comprising the third element of epicyclic gearing arrangement A. The opposite end of hollow shaft 642 is xed to another sun gear 6143, the first element of an epicyclic gearing arrangement B. The sun gear 643 may mesh with planetary gears 644 (only one being shown) fixed to shafts A645. Shafts 6415, journaled in an arm 646, form the second element 647 of the epicyclic gearing arrangement B'. Shafts 645 also have fixed to them planetary gears 648. Planetary gears 648 mesh with a gear 649 fixed to one end of a hollow shaft 650 forming the third element of the epicyclic gearing arrangement B. The opposite end of shaft 658 is fixed to sun gear 1651, the first element of an epicyclic gearing arrangement C'. The sun gear 651 may mesh with Iplanetary gears 652 (only one `being shown) fixed to shafts 653. Shafts 1653, journaled in arm 654, form the second element 655 of the epicyclic gearing arrangement C. The shafts 653 also have fixed to them planetary gears 656. Planetary gears 656 mesh with gear 657 fixed to one end of shaft 658 forming the third element of the epicyclic gearing arrangement C'. The opposite end of the shaft 658 is fixed to helix gears 659 that mesh 'with helix gears `660. Helix gears 660 mesh with helix gears 661 that are xed to the hollow shaft `522, which latter is internally keyed to the shaft 521.

An axially slidable, positive action clutch 662 is adapted to cooperate with positive action clutch-engaging teeth 663 on the second element 639 of the epicyclic gearing arrangement A' and with a stationary gear 664 connected to plate 665 of the headstock HS. Accordingly, with clutch l662 in its rightward position as shown, the second element 639 is caused to be locked to planetary gears 640, 636, sun gear 635 and gear 641, forming an integral cluster of gears that is xed to shaft 623, causing hollow shaft 642 to rotate with shaft 623. Shifting of clutch `662 `to the lef-t will engage positive action clutchengaging teeth 663, on the second element 639, with the stationary gear 664 on a stationary plate 665. This action stops the second element 639 of the planetary A', allowing sun gear 635, planetary ygears 636, 640, and gear 641 to rotate freely, thereby effecting a straight .gear reduction between shaft 6213 and shaft 642.

A positive action, slidable clutch 666 is adapted to cooperate with positive action, clutch-engaging teeth 667 on the second element 647 of the epicyclic gearing arrangement B', and with either planetary gears 644 or a stationary `gear 668 connected to stationary plate 669 of the headstock HS. Planetary gears 644 have a series of holes i670 that cooperate with pins 671 fixed to clutch 6616. Accordingly, shifting of clutch 666 to the lright will engage holes 670 in Iplanetary gear 644 with pins 671 fixed to clutch 666, locking planetary gears 644, 648, sun gear 643 and gear 649, forming an integral cluster of gears that is fixed to shaft 642, causing shaft 650 to rotate with shaft` i642. Shifting of clutch 666 to the left will engage positive action, clutch-engaging teeth 667 on the element 647 with the stationary gear 668 fixed to plate '669, connecting the second element 647 with plate 669, and allowing planetary gears 644, 648, sun gear 643 and gear 649 to rotate freely, thus effecting a straight gear reduction between shaft 642 and shaft 650.

A. positive action, slidable clutch 672 is adapted to cooperate with positive action clutch teeth 673 on the second element 655 of the epicyclic gearing arrangement C' and with either planetary gears 652 or stationary gear 656 connected to plate 657 of the headstock HS. The planetary gears 652 have a series of holes 6581' that cooperate with pins 659' (see FIG. 3A) fixed to clutch 672. Accordingly, shifting of clutch 672 to the right will engage holes 658 in planetary gear 652 with pins 659 fixed to clutch 672, locking planetary gears 652 656, sun gear 651 and gear 657, forming an integral cluster of gears that is fixed to shaft 650, causing shaft 658 to rotate with shaft 650. Shifting of clutch 672 to the left will engage positive action clutch teeth 673 on the element 655 with the stationary gear 656' fixed to plate 657'. This causes the second element 655 to become integral with plate 657', thereby allowing planetary gears 652, 656, sun gear 651 and gear 657 to rotate freely, thus effecting a straight gear reduction between shafts 650 and 658. Clutch 672 has a neutral position to permit shaft 521 to be turned by hand without being affected by any of the gears within the headstock HS.

It is evident that the selective shifting of clutches 633 and 634 provides four different rates of rotation of shaft 623, and the selective shifting of clutches 662, 666 and 672 provides seven different ranges of rates of rotation through epicyclic gearing arrangements A', B' and C. This, then, provides twenty-eight different rates of rotation of output shaft 658 with a single rate of rotation of the input shaft 584 upon the shifting of the clutches 633 and 634 (see FIG. 8).

From the foregoing it is evident that thel various clutches are required to be shifted in a predetermined pattern in order to vary the speed of the output shaft 658. Referring to FIG. 6, this may be accomplished by providing a plurality of cams 674, 675, 676, 677, 673, 679, 680 and 681 fixed to a shaft 683. The shaft 683 is adapted to be turned in a forward and reverse direction to produce different rates of rotation of output shaft 658 by reversing electric motor 684. Motor 684 is connected to shaft 683 through worm 685 on motor shaft 686 and worm wheel 687 on shaft 683. A pointer 688 is connected to shaft 683 for indicating -on a fixed dial 689 the rate of rotation of spindle S.

Valves 690, 691, 692, 693, 694, 695, 696 and 697 may be associated with cams 674 to 681, respectively. The valves 690 to 697 may be supplied with liquid under pressure from a supply line 698. Separate lines 699, 700, 701, 702, 703, 704, 705 and '706 may supply the pressure liquid to operating pistons, as will be described later.

Referring to FIGS. 7 and 3, valve 690 may be connected to a cylinder 707 by line 699. Liquid under pressure may be supplied constantly from line 708 to a space 709 between two pistons 710 and 711 that are slidable on a piston rod 714, thereby separating them so that they abut against limit stops 712 and 713 when the opposite sides of said pistons are exhausted. The liquid in space 709 acts on the sides of the pistons 710 and 711 having the smallest area, while constant pressure liquid from line 699 will act on the side of piston 710 having the largest area when valve 690 is in elevated position. Valve 691 may also be connected to cylinder 707 by line 700 with constant pressure liquid from line '700 acting on the side of the piston 711 having the largest area when it is in elevated position. The piston rod 714 is connected to clutch 634, and upon depressing either valve 690 or 691, it will shift either gear 621 or gear 622 to effect its connection to shaft 623 through gear 624.

Valve 692 (FIG. 6) may be connected to a cylinder 715 (FIG. 3) by line 701. Liquid under pressure from line 716 is constantly supplied to space 717 between pistons 718 and 719, similar to pistons 710, 711,. thereby separating them so that they abut against limit stops 720 and 721 when the opposite sides of said pistons are exhausted. The liquid in space 717 acts on the sides of the pistons 718 and 719 having the smallest area, while constant pressure liquid from line 701 acts on the side of the piston 718 having the largest area, so that when valve 692 is in elevated position, piston rod 720' moves rightwardly. Valve 693 may also be connected to cylinder 715 by line 702. With constant pressure liquid from line 702 acting on the side of the piston 719 having the largest area, and with valve 692 exhausting, rod 720 will move leftwardly. The piston rod 720 is connected to clutch 633 for shifting either gear 628 or 629 to effect its connection to shaft 584 through gear 630.

Valve 694 (FIG. 6) may be connected to a cylinder 721 (FIG. 3) by line 703. Liquid under pressure from line 722 acts on the side of piston 723 having the smallest area, while constant pressure liquid 'from line 703 acts on the side of the piston 723 having the largest area when valve 694 is in its elevated position. Piston 723 may include a piston rod 724 that has a linger 724 which engages clutch 662. When valve 694 is depressed, clutch 662 is in the position shown in FIG. 3; and when valve 694 is in its elevated position, clutch 662 connects teeth 663 and gear 664.

Valve 695 (FIG. 6) may be connected to a cylinder 725 (FIG. 3) by line 704. Liquid under pressure from a line 726 acts on the side of piston 727 having the smallest area, while constant pressure liquid from line '704 acts on the side of the piston 727 having the largest area. Piston 727 may include a piston rod 728 having a linger 729 which engages clutch 666. When valve 695 is depressed, clutch 666 is in the position shown in FIG. 3; and when valve 695 is in its elevated position, clutch 666 connects teeth 667 and gear 668.

Valve 696 (FIG. 6) may be connected to a cylinder 730 (FIG. 3) by line 705. Liquid under pressure `from line 731 acts on the sides of pistons 732 and 733 having the smallest area, while constant pressure liquid from line 705 acts on the side of the piston 733 having the largest area. Valve 697 may also be connected to cylinder 730 by line 706, supplying constant pressure liquid to the side ofthe piston 732 having the largest area. Pistons 732 and 733 may include a piston rod 734 having a finger 735 which enga-ges clutch 672. With valves 696 and 697 depressed (exhausting), the clutch 672 is in the position shown in FIG. 3. With valve 696 in its elevated position and valve 697 depressed, Iclutch 672 engages gears 652 through pins 659'; and when valve 697 is in its elevated position and valve 696 is depressed, clutch 672 connects teeth 673 and gear 656.

Referring to FIGS. 6, 7 and 8, the cams 674 to 681, in-

clusive, have notches 736 that are shown as shaded portions on the stretch-out of FIG. 8. These notches cooperate with valves 690 to 697, inclusive, for eecting the shifting of piston rods 714, 724, 728 and 734. The notches are so arranged that the twenty-eight different combinations of speed of spindle S are sequentially produced as the shaft 686 continues to rotate. The motor 684 is energized by the manual closing of a switch and it will make a single revolution if the energizing switch is immediately released, as will be described later. Each revolution of shaft 686 produces one of the twenty-eight speeds of rotation 'of the spindle S.

Referring to FIGS. l and 9, the variable speed transmission VS may comprise a shaft 741 (FIG. 9) having a gear 745 lixed thereto, said shaft being connected by suitable means such as gearing 742 to a prime mover such, for example, as a constant speed AC. motor (not shown). The input shaft 741 may be connected to a first element of an epicyclic gearing arrangement D located in one path of power flow. In the embodiment disclosed, the shaft 741 is shown as connected to a sun gear 744 through gearing 745 and 746, `although it is evident that any one of the three power transmitting elements of the epicyclic gearing arrangement D could have been selected.

Spur gearing including gears 745 and 747 is shown as driving a shaft 748 from shaft 741 in the same direction as gear 746 is driven from shaft 741, although the direction of rotation of shaft 748 relative to gear 746 is immaterial as will be explained hereinafter. The shaft 748 is connected to a first element of another epicyclic gearing arrangement E located in another path of power flow. While the shaft 748 may be connected to any one of the three power transmitting elements of the arrangement E, it is shown as being connected to a sun gear 749 thereof.

A gear 743 drives a positive displacement variable volume hydraulic unit 750 from gear 745, the variable displacement of which can `be changed by the movement of a lever 751 between two limiting positions at which the unit 750 delivers liquid under pressure at maximum capacity in opposite directions of flow. When the lever 751 is at its midpoint of movement, no fluid is delivered by the unit 750.

The unit 750 may be of `any positive displacement, variable capacity type and it may be connected to a positive displacement, non-variable hydraulic unit 752 within a closed circuit including lines 753 and 754. The unit 752 may be connected to a shaft 755 that supports a gear 756 in mesh with a gear 757 mounted on a Second element 758 of the epicyclic gearing arrangement D. Gear 757 may mesh with a gear 759 on a second element 760 of the epicyclic gearing `arrangement E.

From the foregoing it is evident that the hydraulic units 750 and 752 comprise a variable speed device that is connected to a second element of each of the epicyclic arrangements D and E. While a hydraulic, steplessly variable speed device driven from the gear 743 has been disclosed, it is to be understood that the variable speed device need not be of the stepless variety or of the hydraulic type. It may comprise any form of Variable speed device that can be adjusted in two directions throughout its range of speed variation. It may be driven by an external source of power, although when so driven, under certain circumstances a loss of feedback power is experienced which latter can be utilized to advantage to a certain degree and under certain conditions of operation when the variable speed device is driven from the input shaft 741.

The second elements 758 and 760 of the arrangements D and E are shown as being rotated in opposite directions, but this is only exemplary and not to be considered as a limitation. The only reservation is that rotation of the first and second elements of Ieach of the arrangements D and E should be such that as the variable speed device 750, 752 is operated to increase or decrease in speed, the speed of rotation of the third power transmitting element of one of the arrangements D or E increases while the speed of the third element of the other decreases.

In the embodiment disclosed, the third element of the arrangement D may comprise a shaft 761 having an arm 762, to each of the outer ends of which a planet gear 763 is journaled. The planet gears 763, of course, mesh with the sun gear 744 as well as with internal gear teeth 764 of the second element 758 of the arrangement D.

The third element of the E arrangement may comprise a shaft 765 similar to shaft 761 and having an arm 766 journaling planet gears '767 that mesh with the sun gear 749 and the internal gear teeth 768 on the second element 760.

Dissimilar ratio gearing may be provided between the shafts 761, 765 and the output shaft 740. This gearing may comprise worm 769 lixed to shaft 761 that meshes with a worm gear 770 lixed to a shaft 771; a worm 772 fixed to :shaft 771 may mesh with a worm gear 773 mounted on shaft 740 with an overriding clutch 773 therebetween for a purpose to be described later. A clutch element 774 may be splined to shaft 740 and it may cooperate with clutch engaging means on a clutch 9 element 775 xed to shaft 765 in a manner presently to be described.

The hydraulic unit 758 is adapted to drive shaft '755 at a maximum speed in one direction at a 1:1 ratio, when its lever 751 is in the number 1 position, and to drive shaft 755 at a maximum speed in the opposite direction at a 1:1 ratio when lever 751 is in its number 3 position. When lever 751 is in its number 2 position, shaft 755 is not driven by unit 758. With the shaft 755 rotating at a maximum speed in either direction, the reactors 758 and 760 are rotating in opposite directions at maximum speed. Since the sun gears 744 and 749 are rotating in the same direction, it is evident that the shaft 761 or 765 of the epicyclic gearing arrangements D or E, the reactor of which is rotating oppositely to its sun gear, will rotate at a speed below base speed of its corresponding arrangement, While the other shaft of the two will be rotating at a speed above base speed. Assuming that the arrangement D is the one in which its reactor 758 rotates oppositely to its sun gear 744 when lever 751 is in its number 1 position, if the proper gear ratios and the proper speed of shaft 755 are employed, shaft 761 can be standing still when reactor 758 is rotating at the proper speed incident to lever 751 being in its number 1 position.

With clutch 774 in the position shown in FIG. 9, and moving lever 751 toward its number 2 position, the speed of shaft 740 will increase, through the action of overriding clutch 773', steplessly from zero to a speed coincident with the lever 751 arriving at its number 2 position where reactor 758 is stopped and shaft 761 is rotating at the base speed of the arrangement D. Continued movement of lever 751 toward its number 3 position causes reactor 758 to increase in .speed from zero, but in a direction reversely to that in which it was rotating during the period when lever 751 was moved from its number 1 to its number 2 position. Expressed differently, reactor 758 now rotates in the direction of its sun gear 744. This, of course, causes shaft 761 and shaft 740 to increase in speed to `a maximum for the transmission of power through the epicyclic gearing arrangement D.

When lever 751 is at its number 3 position, the reactor 768 is rotating in a direction opposite to its sun gear 749 and at a maximum :speed so that shaft 765 is rotating at a speed below the base speed of the epicyclic gearing arrangement E. By employing the proper gear ratio between shaft 761 and shaft 748, the speed of shaft 765 can be slightly greater than the speed of shaft 740 when lever 751 is in its number 3 position so that clutch 774 can be shifted into engagement with clutch element 775 without tooth-on-tooth engagement, the overriding clutch permitting shaft 740 to be rotated at the slightly greater speed of shaft 765.

Movement of lever 751 from its number 3 position to its number 2 position causes reactor 760 to decrease in speed to a stopped condition and consequently causes a stepless increase in speed of shaft 765 and shaft 740. Movement of lever 751 to its number 1 position, of course, reverses the rotation of reactor 760, causing the speed of shafts 765 and 740 to continue to increase to the top limit of the epicyclic gearing arrangement E.

By employing a relatively high gear ratio between shaft 761 and shaft 740, and a direct connection between shaft 765 and shaft 740, during initial movement of lever 751 from its number 1 position to its number 3 position and with clutch 774 in neutral, the speed of shaft 740 can be steplessly varied over a relatively small range of speeds, i.e., speeds from to about 23 rpm. And, during movement of lever 751 from its number 3 position to number 1 position, with clutch 774 clutched to element 775, the speed of shaft 748 may be steplessly varied from 23 r.p.m. to about 950 r.p.m. Accordingly, the low range of 0 to 23 r.p.m. as well as the lower end of the high range may be utilized for feed movements of the tool, and the range 10 of 0 to 950 rpm. may be utilized for traverse speeds of the tool. These speeds of shaft 740 are merely one example that results from the selection of certain gear ratios. It is, of course, understood that any desired low and high speed range can be achieved by the proper selection of gear ratios.

In order to operate the feedworks transmission to cause movement of the movable members of the machine tool at any predetermined feed or traverse speed, a control for the feedworks is provided.

Referring to FIGS. 10 to 20, inclusive, and particularly to FIGS. 10, 11 and 12, the control may include a boxlike housing 777 having a pistol grip 778 attached thereto and adapted to be held by one hand of an operator. A

' multi-conductor cable 779 may lead from the top of boxlike housing 777 and it may extend to the housing (not shown) for the transmission including the clutches 515, 554, 569 and 581 (FIG. 2) in which may be included solenoid operated valves 780 to 787, inclusive. The valves 780 to 787, inclusive (FIG. 20) may be provided with a common constant pressure line 788, and valves 780 to 787 may also be provided with solenoids 789 to 796, respectively.

Referring to FIG. 21, the solenoids 789 to 796, inclusive, may be included in circuits including manually operable push-button switches 797 to 8114, respectively. Referring to FIGS. 10 to 12, the housing 777 may be provided with a plate 805 at the top of the grip 778 on which are mounted four directional pushbuttons 806, 807, 808 and 809. These pushbuttons may be arranged such that holding of the grip 778 in the one hand of the operator permits his thumb to be employed to depress any one or two adjacent pushbuttons 806 to 809 at will. Outlet lines 810 to 817 of the valves 780 to 787, inclusive, may lead to the hydraulic clutches 515, 554, 569 and 581 as shown in FIG. 2.

From the foregoing it is evident that depressing pushbutton 806 as shown closes switch 797 which will energize solenoid 789 (FIG. 21), thereby operating valve 780 (FIG. 20), causing pressure liquid to flow through line 810 and rendering eifective gear 513 (FIG. 2) to cause head H to move upwardly. Additionally and in the same way, depressing pushbuttons 808, 807 and 809 closing switches 798, 799 and 800 will cause the head H to move downwardly and the saddle S to move leftwardly and rightwardly, respectively. Additionally, turning the plate 805 counterclockwise 45 and then depressing pushbutton 808 closes switch 801 (FIG. 21) through rod 818 (FIG. 19), energizing solenoid 793 (FIG. 20), thereby operating valve 784 causing pressure liquid to ow through line 814 and rendering effective gear 567 (FIG. 2) to cause table T to advance. Furthermore, and in the same way, depressing buttons 806, 809 and 807 closes switches 804, 883 and 802, extending spindle S, retracting spindle S and withdrawing table T, respectively.

Referring to FIG. 9, in order to control the flow of power through the variable speed transmission VS, means may be provided for moving the lever 751 between its various positions. In the embodiment disclosed, this means may comprise a reciprocable piston 819 that is connected to the lever 751. The movement of piston 819 may be effected by a servomechanism including a reciprocable cam 820 and a servo valve 821. The servo valve may include a spool 822 that is resiliently urged by a spring 823 into engagement with a cam 824 fixed to one end of piston 819. Constant pressure and exhaust lines 825 and 826 are connected to the valve 821 such that the spool 822 blocks both when in its normal position or the position to which it returns after being displaced. Another line 827 is connected to valve 821 between the lines 825 and 826. Line 827 leads to the top of piston 819. A constant pressure line 828 continuously acts on piston 819 tending to return it to the position shown in FIG. 9; however, the area of piston 819 acted upon by pressure iuid from line 828 is less than that acted upon by pressure uid from line 827 so that the latter overcomes the former when it is effective.

The valve 821 may be pivotally mounted at 829 and it may include a cam roller 830 that follows a cam surface 831 on cam 820. With the parts in the condition shown in FIG. 9, the lever 751 is in its number 1 position, and the units 750 and 752 are rotating at maximum speed in one direction. Movement of the cam 820 upwardly will cause the valve 821 to pivot counterclockwise about pivot 829 by the action of spring 823 expanding. This causes spool 822 to move leftwardly, establishing communication between lines 825 and 827 while maintaining exhaust line 826 closed. Accordingly, pressure liquid in line 827 forces piston 819 downwardly, moving arm 751 from its number 1 position toward its number 2 position until cam 824 forces spool 822 rightwardly to cut off communication between lines 825 and 827, at which point the pressure liquid within line 827 and above piston 819 is trapped, holding piston 819 and arm 751 in its new position.

As previously described, this causes the speed of the reactor 758 to decrease and that of the shaft 748 to increase from zero. Further upward movement of cam 820 causes the arm 751 to be moved downwardly through its number 2 position, thence to its number 3 position, at which point the follower roll 830 is at the low point of cam path 831 and the reactor 758 is rotataing in a reverse direction at maximum speed. It is at this point that, due to the reduction gearing '769, 778, 772 and 773, shaft 740 has increased in speed from Zero through its low speed range, and reactor 760 is conditioned to take over for the high speed range of operation of shaft 748. The arrangement is such that arm 766 is rotating at a speed .slightly greater than that of shaft 748 so that clutch 774 can be shifted without tooth-on-tooth contact. Shifting of clutch 774 at the proper time is accomplished by a valve 832 having a valve stem 833 connected to the cam 820. When cam 828 is at a position in its upward travel such that the roll 830 is at the low point of cam surface 831, the head 834 of stem 833 establishes communication between lines 835 and 836, whereupon piston device 837 shifts clutch 774 into engagement with arm 775. Immediately, the faster rotating arm '775 takes over from the gear 773 because of the overriding clutch 773.

Further upward movement of the cam 820 causes the roller 830 and valve 821 to move clockwise about pivot 829, thereby forcing spool 822 rightwardly, establishing communication between lines 827 and exhaust line 826, while still retaining line 825 blocked olf. Accordingly, piston 819 begins to rise due to the pressure liquid in line 828 until cam 824 permits spool 822 to move leftwardly enough to close off exhaust line 826. This action of moving cam 820 upwardly may continue until arm 751 has returned to its number 1 position when shaft 740 is rotating at its maximum rate of speed.

Movement of the cam 820 downwardly from its uppermost position causes the shaft 740 to reduce in speed to zero when cam follower 830 is in the position shown in FIG. 9.

The reciprocation of cam 820 during feed movements of the spindle S, saddle S', table T and head H should be related to the speed at which the spindle S is rotated by the headstock HS for feed in inches per revolution. During traverse movement of the spindle S, saddle S', table T and head H, the movement of cam 820 should preferably be unrelated to the rotation of spindle S. In the present embodiment, the function of relating these feed movements to spindle rotation has been accomplished by employing a servo drive 838 between a gear 839 and an auxiliary variable speed device 840 that is driven from the headstock HS that drives shaft 521 forming spindle S (FIG. 3). The servo drive includes an epicyclic gearing train 841, cam 820, valve 821 and cam 824.

Referring to FIGS. 3, l and 9, a gear 842 (FIG. 3)

fixed to hollow shaft 522 meshes with a gear 843 which drives a vertically disposed splined shaft 844 through bevel gears 845. The shaft 844 in FIG. 9 is shown displaced from its position as shown in FIGS. l and 3. The variable speed device 840 includes a disk 846 that must rotate in only one direction when the shaft 521 or spindle S rotates in both directions. In order to accomplish this, a pulley 847 is connected to two pulleys 848 and 849 Which are mounted on ` shafts 850 and 851 through oppositely acting, overriding clutches 852 and 853. Intermeshing gears 854 and 855 fixed to shafts 850 and 851 drive a gear 856 fixed to a shaft 857 to which disk 846 is connected. Disk 846 frictionally drives a disk 847 that is fixed to a reciprocable shaft 848 having a square or splined cross section. With disk 847 in its solid line position at the center of disk 846, shaft 848 does not rotate. Movement of disk 847 toward its dotand dash-position increases the speed of rotation of shaft 848 from zero to a maximum predetermined value.

The speed of rotation of shaft 848 is employed to drive, through bevel gearing 849', a sun gear 850' of the epicyclic gearing arrangement 841. The sun gear 850' meshes with planet gears 851 which in turn mesh with the internal teeth of a ring gear 852. The external teeth of ring gear 852 mesh with gear 839 that is driven from the output shaft 74) of the variable speed unit VS through a gear 853. The planets 851 are journaled in an arm 854' that drives through gear teeth 855 thereon, a gear train 856 including a hydraulically operable clutch 857. When the clutch 857 is effective, gearing 856 drives a shaft 858 to which is fixed a pinion 859 in mesh with a rack 860 integral with the cam 820.

With the parts in the condition shown in FIG. 9, the gear 839 is not rotating, nor is shaft 848. Movement of disk 847 off its center position causes shaft 848 to rotate at a predetermined speed depending upon the distance that disk 847 is moved from center. Since gear 839 is not rotating, the rotation of sun gear 850 rotates arm 854 and hence shaft 858 provided, of course, that clutch 857 is effective. Rotation of shaft 858 may move cam 828 upwardly, thereby effecting the movement of lever 751 from its number 1 toward its number 2 position and hence starting the rotation of gear 839. When the speed of rotation of gear 839 arrives at a predetermined value, it will combine with the speed of rotation of the sun gear 850 and stop the rotation of arm 854. This, of course, stops the movement of cam 820 and also the movement of lever 751. By properly calibrating the offset positions of disk 847 with respect to the speeds of rotation of gear 839, such positions can represent definite feed rates of movement of the head H, saddle S', spindle S and table T, each of which rates will be definitely related to the speed of rotation of the shaft 521 or spindle S as inches per revolution of said spindle.

Reciprocation of shaft 848 may be effected by connecting it to an oscillatable member 861 through a connecting rod 862 and a non-rotatable connector 863 that permits rotation of shaft 848. The member 861 may be provided with bevel gear teeth 864 that mesh with a bevel pinion 865 on a shaft 866 to which is fixed a knob 867 and a stationary dial 868. The dial 868' may be marked to indicate the feed rates in inches per revolution of spindle S corresponding to the calibrated offset positions of disk 847.

From the foregoing it is evident that setting of knob 867 will cause the above-mentioned movable members of the machine tool to move at a predetermined feed rate in inches per revolution related to the rotation of the shaft 521 or spindle S when the clutch 857 is rendered effective.

Referring to FIGS. l0 to 13, and particularly to FIGS. l() and l2, the box-like housing 777 may include a triggerlike element 868 which may extend from within housing 777 outwardly from the bottom thereof and about which lower end may extend a guard 869. The trigger 868 may be fixed to a rotatably mounted shaft 870 mounted within housing 777. Also xed to shaft 870 may be an arm 871 that may be pivotally connected to a vertically disposed rod 872 within housing 777. The upper end of the rod 872 may be pivotally connected to another arm 873 that may be fixed to a cam shaft 874 for a purpose to be described later. An operating lever 875 may also be connected to shaft 870 and may be located on the outside of the housing 777 to supplement the operation of trigger 868. The trigger 868 is held in a neutral position by a spring pressed detent 876 that cooperates with a cam stop 877. Movement of the trigger 868 clockwise from the neutral position (FIG. 13) moves the bar 872 downwardly, thereby rotating a cam 878 fixed to shaft 874. When a notch 879 on cam 878 receives a switch actuator 880 of a normally open switch 881, the latter manually closes, energizing a solenoid 882 (FIGS. and 21, line 24) through closed switch 883. Energizing solenoid 882 actuates valve 883 to cause pressure fluid to ow to clutch 857 (FIG. 9) through a line 884 thereby rendering effective the drive between the servo 838 and the cam 820.

From the foregoing it is evident that changing the feed rate when the trigger 868 is in neutral merely causes the gearing 856 (FIG. 9) to rotate until clutch 857 is rendered effective by switch 881 (FIG. 2l) closing, which occurs when trigger 868 is moved clockwise from its neutral position.

As previously explained, movement of the head H, saddle S', spindle S and table T at traverse rates of speed preferably should not be related to the rotation of the shaft 521 or spindle S. In the embodiment disclosed, this has been accomplished by providing a separate poweroperated drive for moving the cam 820 independently of the epicyclic control gearing 841. Referring to FIG. 9, a member 885 may be fixed to the cam 820 and it may make a telescopic connection with a threaded rod 886. The rod 886 may be threadingly connected to a nut 887 which is pivotally mounted on a lever 888, which latter is pivotally mounted at 889. The threaded rod 886 may include a square end 890 to receive a wrench.

Referring again to FIG. 9, the constant pressure inlet 835 of valve 832 may include a passage 891 that causes the constant pressure liquid to act on the head 834 of the stem 833 constantly urging cam 820 and rod 886 downwardly. The downward extent of movement of the rod 886 is determined by a piston 892 that is urged upwardly into a predetermined position by a spring 893 within a cylinder 894.

From the foregoing it is evident that adjustment of the rod 886 can be made to produce a limiting downward position of the cam 820 to provide a predetermined creep speed of movement for the head H, saddle S', spindle S and table T. This creep speed is effective at the neutral position of the trigger 868; however, unless one of the pushbuttons 806 to 809 is depressed, these members will not move. When any feed movement of the members is initiated, liquid pressure in line 884 leading to the cylinder 894 withdraws piston 892 from its upper limiting position. This make it possible to have a feed rate that is less than the predetermined creep rate.

Referring again to FIG. 9, the cam 820 may be provided with an abutment 895 adapted to be engaged by a finger 896 fixed to a shaft 897. The shaft 897 may also support in fixed relation thereto another finger 898 having a cam follower 899 thereon. The follower 899 may engage the peripheral surface of a cam 900 that is fixed to a shaft 901. The constant pressure acting on valve stem 833, forcing cam 820 downwardly, causes follower 899 to remain in contact with the surface of cam 900. Shaft 901 may be geared to a cam shaft 902 through bevel gearing 903, and cam shaft 902 may be driven by a reversible electric motor 904 through a gear reduction 905. Cams 906, 907 and 908 and 909 may be xed to cam shaft 902 for actuating contacts (910), (911, 912), (913, 914) and (915), respectively, for a purpose to be described later.

Referring to FIG. 13, the cam shaft 874 may have fixed to it, besides cam 878, cams 916, 917 and 918. The cam 878 not only operates feed switch 881, but also a switch 919 (see also FIG. 21, line 31). Cam 916 may actuate a switch 920 having normally closed and open contacts 921, 922 (FIG. 2l, lines 27, 30). And, cam 918 may include a lever 926 that is frictionally driven between stops 927, 928 and adapted to actuate a switch 929 having normally closed and open contacts 930, 931 (FIG. 21, lines 28, 29).

The cam 918 may include a disk 932 keyed to shaft 874 and journalingly supporting a ring 933 on a shoulder 934 thereof. A disk 935 slidably keyed to shaft 874 may be urged toward ring 933 by a disk spring 936. The construction is such that rotation of shaft 874 in a counterclockwise direction will frictionally drive lever 926 into contact with switch 929 to operate it, and then engage stop 928 to cause the ring 933 to slip on shoulder 934. Upon rotation of shaft 874 in a clockwise direction, lever 926 engages stop 927 a very slight distance away from switch 929. In this way, any movement of shaft 874 in either direction will almost instantly operate the contacts 930 and 931 for a purpose to be described later.

With the parts in the position shown in FIG. 9, and assuming that a directional pushbutton 806-809 has been depressed, a selected movable member will be moving at creep speed. Movement of the trigger 868 in a counterclockwise direction causes cam shaft 874 to rotate in a counterclockwise direction, thereby `actuating switch 929 and closing contacts 931 (FIG. 21, line 29) while opening contacts 930 (line 28) thereof. When cam shaft 874 has rotated approximately 10, switch 923 is actuated to open contacts 924 (line 26) and close contacts 925 (line 29). This energizes motor 904 (FIG. 9 and FIG. 21, line 28) in a forward direction, causing cam shaft 902 to rotate in a counterclockwise direction. Immediately, contacts 910 (line 26) close but the reversing circuit for motor 904 is not completed because contact 930 is open. Rotation of cam shaft 902 causes cam 900 to rotate shaft 897 and consequently causes finger 896 to act on abutment 895 that is fixed to cam 820. This moves cam 820 upwardly, thereby increasing the speed of travel of the selected member as previously described. This upward movement of cam 820 continues until cam 908 on cam shaft 902 closes contacts 914 (line 27) and opens contacts 913 (line 29). Closing contacts 914 does not complete a circuit because switch 930 is open. Opening contacts 913 stops motor 904, and the selected member continues to move in the selected direction and at the traverse rate corresponding to the position of cam 820 relative to the stopping of motor 904,

Continued counterclockwise movement of trigger 868 for about eight additional degrees causes operation of switch 920, thereby closing contacts 922 (FIG. 21, line 30) and opening contacts 921 (line 27). Closing contacts 922 re-energizes motor 904 in a forward direction, causing cam shaft 902 to rotate in a counterclockwise direction. This causes cam 900 to move cam 820 farther upwardly, thereby increasing the traverse speed of the selected member in the selected direction. The speed of the selected member increases until cam 907 opens contacts 911 (line 29) and closes contacts 912 (line 28). Closing contacts 912 fails to set up a complete circuit since contacts 930 (line 28) are still open. Opening contacts 911 de-energizes motor 904, whereupon the selected member moves at the traverse rate corresponding to the position of cam 820 as represented by the position of cam 907.

Continued counterclockwise motion of trigger 868 for about another eight degrees causes operation of switch 919 (line 31). This causes re-energization of motor 904 through normally closed contacts 915 (line 30). Accordingly, cam shaft 902 begins to rotate again in a counterclockwise direction, causing cam 900 to move cam 820 still farther upwardly, thereby increasing the traverse speed of the selected member. Cam 900 in its rotation moves iinger 898 counterclockwise, and when the speed of the selected member arrives at its maximum designed value, cam 909 opens normally closed switch 915 (line thereby de-energizing motor 904. Accordingly, the selected member continues to traverse at maximum speed while trigger 868 is held in its furthest counterclockwise position.

In order to provide an increasing resistance to the movement of trigger 868 in a counterclockwise direction, a spring pressed detent 937 (FIG. 13) may be mounted within a cylinder 938 formed within a boss 939 integral with the bar 872. The detent 937 may engage a xed abutment 940 such that as bar 872 moves upwardly, the detent 937 is forced downwardly against the action of a spring 941.

Upon releasing the force holding trigger 868 in its furthest counterclockwise position, the spring pressed detent 937 will cause it and cam shaft 874 to move in a clockwise direction. Immediately, switch 929 is operated by lever 926 moving in a clockwise direction, thereby closing contacts 930 (line 28) and opening contacts 931 (line 29). It will be recalled that contacts 910, 914 and 912 were all closed during the increasing traverse speed of the selected member. Accordingly, motor 904 is energized and caused to rotate reversely, thereby rotating cam shaft 902 in a clockwise direction (FIG. 9). As cam shaft 902 rotates in a clockwise direction, cam 900 rotates in a clockwise direction, thereby permitting cam 820 to descend, causing a decrease in the rate of traverse movement of the selected member. This continues until cam 907 closes contacts 911 (line 29) and opens contacts 912 (line 28). Closing contacts 911 does not establish a circuit because contacts 931 (line 29) are open. Opening contacts 912 de-energizes motor 904, and the selected member continues to travel at the traverse rate corresponding to the position of cam 820 when motor 904 stops.

Continued movement of trigger 868 toward neutral for about eight additional degrees causes the switch 920 to be operated to close contacts 921 (line 27) and open contacts 922 (line 30). Closing contacts 921 re-energizes motor 904 in the reverse direction to cause cam 900 to further reduce the traverse speed of the selected member until cam 908 opens contacts 914 (line 27) and closes contacts 913 (line 29). Closing contacts 913 does not establish `a circuit because contacts 931 (line 29) are still open. Opening contacts 914 de-energizes motor 904, and the selected member continues to traverse at the speed corresponding to the position of cam 820 when motor 904 stops.

yFurther clockwise movement of trigger 868 toward neutral, of about another eight degrees, operates switch 923 to close contacts 924 (line 26) and open contacts 925 (line 29). Closing contacts 924 re-energizes motor 904, thereby effecting the further clockwise movement of cam 900 until cam 820 has descended to a point where lever 888 engages piston 892. At this point, the selected member is moving vat creep speed and cam 906- opens contacts 910 (line 26), thereby de-energizing motor 904. The selected member would continue to move at creep speed but for the release of the selected directional button 806-809.

One of the aspects of the present invention deals with the ability to move the head H, saddle S', spindle S and table T at a rate of speed measured as inches per minute rather than inches per revolution of the spindle S. Referring to FIG. 9, this is accomplished by providing a manual control for moving the cam 820. A knob 942 rotatably mounted relative to a stationary disk 943 that is calibrated in inches per minute drives a shaft 944 through gearing 945. A link 946 lixed to shaft 944 is connected toa cylinder 947. A piston 948 within cylinder 947 is urged downwardly by a spring 949. The piston 948 is connected to a rod 950, to the opposite end of which a link 951 is fixed. The link 951 is connected to the finger 896 which abuts against abutment 895 on the cam 820. When cylinder 947 is exhausted through a line 952, rotation of knob 942 is ineffective during control of the apparatus by the knob 867 or the motor 904. However, when liquid under pressure is admitted to cylinder 947 through line 952, movement of knob 942 controls the position of cam 820 and hence the speed of movement of the head H, the saddle S', the'spindle S or the table T.

Referring to FIG. 20, a valve 953, operated by a solenoid 954, controls the ilow of liquid through line 952. Referring to FIG. 21, the solenoid 954 is energized by manually closing a switch 955 which simultaneously opens switch 883 to prevent rendering effective the clutch 857.

Referring to FIGS. 13 and 16, an interlock may be provided for holding the directional solenoids energized during feeding and traverse movements of the head H, the saddle S', the spindle S and the table T. This interlock may comprise a plate 956 that is urged upwardly by a spring 957, and forced downwardly by the energizing of a solenoid 958 (see also FIG. 2l). The plate 956 may include two irregularly contoured openings 959 and 960 which cooperate with spool ends 961 of the pushbuttons 806, 807, 808 and 809 not only when these buttons are in the position shown in the drawings, but also when they have been turned 45 in a counterclockwise direction. The contours of the openings 959 and 960 are such that when plate 956 is in the position shown in the drawings, the buttons 806-809 may be actuated. However, when plate 956 is moved downwardly, certain portions of the edges of the openings 959, 960 pass into the recesses of the spool ends 961 if the button is not depressed, thereby preventing the actuation of buttons 806-809. If a button 806-809 is depressed, these edge portions will engage the outside of the righthand flange of the spool ends 961, thereby retaining the button depressed after removal of the operators finger. The plate 956 includes a lug 962 that cooperates with the boss 939 on the bar 872.

Movement of the trigger 868 in a clockwise direction with a selected button 806-809 depressed causes boss 939 on bar 872 to force plate 956 downwardly against the action of spring 957. This locks the depressed button 806- 809 in effective position so that the selected member moves at a rate set up by the operation of either knob 867 or 942 (FIG. 9). When the trigger 868 is moved clockwise, spring pressed detent 876 cooperates with a notch in cam stop 877, retaining trigger 868 in its feed position until positively returned to neutral by the 0perator. Upon movement of trigger 868 to its neutral position, boss 939 moves upwardly, permitting spring 957 to move plate 956 upwardly, thereby releasing the depressed button 806-809.

Movement of the trigger 868 counterclockwise (FIG. 13), with a selected button 806-809 depressed, moves boss 939 away from lug 962 and rotates cam shaft 874, causing motor 904 to be energized as previously described. This rotates cam 900, causing lever 898 to turn counterclockwise (FIG. 9) until a cam 963 permits closing of la switch 964 (see also FIG. 21). This action occurs at a predetermined rate of movement of the movable member that was selected by the depressing of a selected pushbutton 806-809. Closing switch 964 energizes solenoid 958, moving plate 956 downwardly to lock the depressed button 806-809 in effective position. Releasing trigger 868 causes it to return to neutral by the action of spring pressed detent 937, and when the traverse speed of the selected member has reduced to the predetermined speed previously mentioned, the cam 963 opens switch 964, de-energizing solenoid 958 and permitting spring 957 to raise plate 956, thereby releasing the depressed button 806-809.

Closing switch 965 in L1 supplies power to the electrical circuit shown in FIG. 21, energizes solenoid 966 (line 6) which supplies pressure liquid to line 618 (FIG. applying brake band 616; and also energizes relay CR4 (line 12) if switch 967 (line 12) is closed, which latter will be closed if the spindle S is below about r.p.m. Energizing relay CR4 (line 12) closes CR4-1 contacts (line 3) and CR4-3 contacts (line 7), and opens CR4-2 contacts (line 5).

Closing pushbutton switch 968 energizes CR1 relay (line 1) which closes CE1-1 contacts (line 2) to hold CR1 relay energized when switch 963 is released. It also opens contacts CRI-2 (line 6), cle-energizing solenoid 966 thereby releasing the brake. Closing of contacts 968 also energizes solenoid 969 (line 2) through contacts CR4-1 which are now closed, since as shown switch 97()` for spindle forward motion is closed. Energizing solenoid 969 causes pressure liquid to enter line 602 (FIG. 5), causing gear 589 to drive shaft 587 to rotate spindle S in the forward direction at a speed determined by the rotary position of the cams on shaft 683 (FIG. 6).

The energizing of relay CR1 (line 1) also opens CE1- 3 contacts (line 7) so that when CR4-3 contacts (line 7) are closed, the circuit for motor 684 (line 9) cannot be energized and no change of spindle speed can be etected at this time, and the spindle S rotates in a forward direction at a rate depending upon the setting of the cams on shaft 683.

Energizing CR1 relay (line 1) also closes CR1-4 contacts (line 14) w-hich energizes relay CRS (line 13) and time delay relay TR1 (line 14) since switch 970 (line 14) is closed and because the spindle S is rotating in a forward direction. Energizing CRS relay closes holding contacts CRS-1 (line 13) and closes contacts CRS-2 (line 4).

Energizing TR1 relay (line 14) causes closing of TR1- 1 contacts (line 4) and opening of TR1-2 contacts (line S) after about six seconds, permitting spindle S to rotate at a speed in excess 4of about l5 r.p.m. when switch 967 opens, de-energizing relay CR4 (line 12) which opens contacts CR4-1 (line 3) which, if TR1-1 contacts were not closed, would cause the solenoid 969 to de-energize, stopping spindle S. De-energizing CR4 relay (line 12) also closes contacts CR4-2 (line 5) but TR1-2 contacts are now open. It also opens CR4-3 contacts (line 7 When it is desired to change the speed of rotation of spindle S, it is rst necessary to stop its rotation by opening switch 971 (lines 1 and 19). Opening switch 971 (line 19) -de-energizes solenoid 958, causing interlocking plate 956 (FIG. 16) to move upwardly, releasing the selected pushbutton 806-809. Opening switch 971 (line 1) de-energizes CR1 relay (line 1) and also deenergizes solenoid 969 (line 3), causing the exhaust of pressure liquid from line 602 (FIG. 5), disengaging the forward driving clutch for the spindle S. 13e-energizing CRI relay (line 1) opens CR1-1 contacts (line 2), CRI- 4 contacts (line 14), and closes CRI-2 contacts (line 6) and CR1-3 contacts (line 7). Closing CRl-Z contacts energizes solenoid 966, applying brak-e band 616 (FIG. 5), stopping spindle S. Closing contacts CR1-3 (line 7) sets up the circuit for motor 684 (line 9) since CR4-3 contacts (line 7) are now closed because switch 967 (line 12) opens when the speed of spindle S is below about l5 r.p.m. as previously described.

Assuming that it is desired to rotate spindle S at a slower speed, closing pushbutton switch 972 energizes CR2 relay (line 7 Energizing CRZ relay closes GRZ-1 and CR2-2 contacts (line S) and opens CR2-3 contacts (line 19). The opening of the latter prevents activation of motor 684 through pushbutton switch 973. With switch 972 held closed, motor 634 is rotated in a direction to cause an ncreased speed ratio of gearing to be established in the headstock HS, and as motor 684 begins to rotate, switch 974 closes and re-opens for each revolution of shaft 686 (FIG. 6). Accordingly, the switch may be instantly closed and opened to produce one revolution of shaft 686 or it may be held closed until the desired speed is indicated `by pointer 688 on dial 689, and upon release of switch 972, the motor 684 will stop at the end of its revolution by opening switch 974.

In a similar manner, if it is desired to increase the speed of spindle S, push'button switch 973 is closed to reverse the rotation of motor 684. To start spindle S again, it is necessary to initially close switch 968, as previously described and to depress any desired button 806-309.

When it is desired to rotate the spindle S in a reverse direction without a speed change in the spindle, it is only necessary to move the switch 971) (line 3) so that its contacts (line 4) close and those in line 3 open. This is true because until a speed change is effected, the CRS relay (line 13) remains energized, maintaining contacts CRS-2 (line 4) closed. When switch 971) is so moved, solenoid 974 is energized and solenoid 969 is de-energized. This causes pressure liquid to be applied to line 612 and to be exhausted from line 602 so that shaft 592 (FIG. 5) now drives spindle S through shaft 587. However, when a speed change in spindle S is required prior to reversing the rotation of spindle S, it is first necessary to cause the spindle to rotate forwardly at the new speed suiciently to cause proper intermeshing of the clutches within the headstock HS. Accordingly, the new speed of spindle S is set up as previously described with switch 970 in the position shown in FIG. 21, and upon closing switch 968, the spindle will start rotating forwardly. Then, the switch 970 may be operated as previously described to effect reversal of the rotation of spindle S.

Although the various features of the new and improved horizontal boring mill have been shown and described in detail to fully disclose one embodiment of the invention, it will be evident that changes may be made in such details and certain features may be used without others without departing from the principles of the invention.

What is claimed is:

1. In a horizontal boring mill, a table adapted to be moved along a path; a saddle supporting said table and adapted to be moved along a path at right angles to the path of movement of said table; a head movable along a third path at right angles to both said other paths; a rotatable, reciprocable spindle within said head; separate means for moving said table, saddle, head and spindle; a clutch case including identical reversing gear means for each of said separate means; a steplessly variable speed transmission for driving said reversing gearing, including a steplessly variable hydraulic transmission; a servomechanism for adjusting said hydraulic transmission, including a reciprocable cam; means normally urging said cam in one direction; a control adapted to be carried in one hand of an operator and including a pistol grip; a trigger mounted in said control and located in a neutral position relatively to said pistol grip to be operable by the index finger of the hand holding said control; means on said control for rendering effective selected of said reversing gear means for causing movement of a selected of said table, saddle, head and spindle; and means rendered effective when said trigger is moved from its neutral position for moving said cam to actuate said servomechanism to thereby cause the selected table, saddle,

head or spindle to be moved at a rate depending upon the position of said trigger.

2. In a horizontal boring mill, a table adapted to be moved along a path; a saddle supporting said table and adapted to be moved along a path at right angles to the path of movement of said table; a head movable along a third path at right angles to both said other paths; a rotatable, reciprocable spindle within said head; separate means for moving said table, saddle, head and spindle; a clutch case including identical reversing gear means for each of said separate means; a steplessly variable speed transmission for driving said reversing gearing, in-

cluding a steplessly variable hydraulic transmission; a servomechanism for adjusting said hydraulic transmission, including a reciprocable cam; means normally urging said cam in one direction; a control adapted to be carried in one hand of an operator and including a pistol grip; a trigger mounted in said control and located in a neutral position relatively to said pistol grip to be operable by the index finger of the hand holding said control; means on said control for rendering effective selected of said reversing gear means for causing movement of a selected of said table, saddle, head and spindle; means rendered effective when said trigger is moved from its neutral position for moving said cam to actuate said servomechanism to thereby cause the selected table, saddle, head or spindle to be moved at a rate depending upon the position of said trigger; and means for increasing the resistance to the movement of said trigger the farther it is moved from said neutral position.

3. In a horizontal boring mill, a table adapted to be moved along a path; a saddle supporting said table and adapted to be moved along a path at right angles to the path of movement of said table; a head movable along a third path at right angles to both said other paths; a rotatable, reciprocable spindle within said head; separate means for moving said table, saddle, head and spindle; a clutch case including identical reversing gear means for each of said separate means; a steplessly variable speed transmission for driving said reversing gearing, including a steplessly variable hydraulic transmission; a servomechanism for adjusting said hydraulic transmission, including a reciprocable cam; means normally urging said cam in one direction; a control adapted to be carried in one hand of an operator and including a pistol grip; a trigger mounted in said control and located in a neutral position relatively to said pistol grip to be operable by the index nger of the hand holding said control; means on said control for rendering effective selected of said revering gear means for causing movement of a selected of said table, saddle, head and spindle; means rendered effective when said trigger'is moved from its neutral position for moving said cam to actuate said servomechanism to thereby cause the selected table, saddle, head or spindle to be moved at a rate depending upon the position of said trigger; and interlocking means responsive to the movement of said trigger for preventing the selection of any other than the selected table, saddle, head or spindle when said trigger is displaced from its neutral position.

4. ln a horizontal boring mill, a table adapted to be moved along a path; a saddle supporting said table and adapted to be moved along a path at right angles to the path of movement of said table; a head movable along a third path at right angles to both said other paths; a rotatable, reciprocable spindle Within said head; separate means for moving said table, saddle, head and spindle; a clutch case including identical reversing gear means for each of said separate means; a steplessly variable speed transmission for driving said reversing gearing, including a steplessly variable hydraulic transmission; a servomechanism for adjusting said hydraulic transmission, including a reciprocable cam; means normally urging said cam in one direction; a control adapted to be carried in one hand of an operator and including a pistol grip; a trigger mounted in said control and located in a neutral position relatively to said pistol grip to be operable by the index finger of the hand holding said control; means on said control for rendering effective selected of said reversing gear means for causing movement of a selected of said table, saddle, head and spindle; means rendered effective when said trigger is moved from its neutral position for moving said cam to actuate said servomechanism to thereby cause the selected table, saddle, head or spindle to be moved at a rate depending upon the position of said trigger; and solenoid operated, interlocking means responsive to a predetermined speed of movement of the selected table, saddle, head or spindle for preventing the selection of any other than the selected one.

5. In a control for a horizontal boring mill having a table, saddle, head and spindle adapted to be moved in either direction along separate paths, the combination comprising a box-like housing having a pistol grip adapted to be held in one hand of an operator; a series of contact actuators arranged in a circle in a location on said housing such that the thumb of the hand holding said grip can with facility actuate any one of said contact actuators; solenoid valves for controlling the movement of said head, table, saddle and spindle adapted to be rendered effective by the actuation of selected of said contact actuators; a trigger adjacent said grip and extending into said housing; a cani shaft in said housing; a Connection between said cam shaft and trigger for causing said cam shaft to rotate in opposite directions when said trigger is moved to either side of a neutral position; cams on said cam shaft; a switch mounted within said housing and operable by one of said cams when said trigger is moved in one direction from said neutral position for causing a selected of said table, saddle, head or spindle, depending upon which Contact actuator is rendered effective, to move at a preselected feed rate; and a plurality of other switches Within said housing, successively rendered effective by other of said cams when said trigger is moved to successive positions on the other side of said neutral position for causing said selected table, saddle, head or spindle to move at successively increasing traverse rates.

6. In a control for a horizontal boring mill having a table, saddle, head and spindle adapted to be moved in either direction along separate paths, the combination comprising a box-like housing having a pistol grip adapted to be held in one hand of an operator; four' Contact actuators mounted in an angularly disposable disk and arranged in a circle in a location on said housing such that the thumb of the hand holding said grip can with facility actuate any one of said contact actuators; means for turning said disk; solenoid valves for controlling the movement of said head, table, saddle and spindle adapted to be rendered effective by the actuation of selected of said contact actuators; a trigger adjacent said grip and eX'- tending into said housing; a cam shaft in said housing; a connection between said cam shaft and trigger for causing said cam shaft to rotate in opposite directions when said trigger is moved to either side of a neutral position; cams on said cam shaft; a switch mounted Within said housing and operable by one of said cams when said trigger is moved in one direction from said neutral position for causing a selected of said table, saddle, head or spindle, depending upon which contact actuator is rendered effective, to move at a preselected feed rate; and a plurality of other switches Within said housing, successively rendered effective by other of said cams when said trigger is moved to successive positions on the other side of said neutral position for causing said selected table, saddle, head or spindle to move at successive increasing traverse rates.

'7. ln a horizontal boring mill, a table adapted to be moved along a path; a saddle supporting said table and adapted to be moved along a path at right angles to the path of movement of said table; a head movable along a third path at right angles to both said other paths; a rotatable, reciprocable spindle Within said head; a headstock transmission for rotating said spindle; separate means for moving said table, saddle, head and spindle; a clutch case including identical reversing gear means for each of said separate means; a steplessly variable speed transmission for driving all of said reversing gearing, including a steplessly variable hydraulic transmission; a servomechanism for adjusting said hydraulic transmission, including a reciprocable cam; a variable speed control transmission driven by said headstock transmission; an epicyclic gearing train between the output of said control transmission and the output of said steplessly variable speed transmission for moving the cam of said servomechansm; means adapted to preset said control Variable speed transmission for causing said servomechanism to adjust said hydraulic transmission; means adapted to be moved to one side of a neutral position for causing a selected of said table, saddle, head or spindle to be moved at a rate depending upon the preset condition of said control transmission; and means rendered eiective when said last mentioned means is moved to the other side of said neutral position for causing said selected of said table, saddle, head or spindle to be moved at a rate depending upon the position of said last mentioned means and independent of said control transmission.

References Cited by the Examiner UNITED STATES PATENTS Williamson 77-3 Stephan 773 Jones 74-769 Hollis 74-769 Hause 77-3 Grinage 77--3 Bullard 74-750 Bullard 74-675 WILLIAM W. DYER, IR., Primary Examiner.

LEN PEAR, Examiner.

Claims (1)

1. IN A HORIZONTAL BORING MILL, A TABLE ADAPTED TO BE MOVED ALONG A PATH; A SADDLE SUPPORTING SAID TABLE AND ADAPTED TO BE MOVED ALONG A PATH AT RIGHT ANGLES TO THE PATH OF MOVEMENT OF SAID TABLE; A HEAD MOVABLE ALONG A THIRD PATH AT RIGHT ANGLES TO BOTH SAID OTHER PATHS; A ROTATABLE, RECIPROCABLE SPINDLE WITHIN SAID HEAD; SEPARATE MEANS FOR MOVING SAID TABLE, SADDLE, HEAD AND SPINDLE; A CLUTCH CASE INCLUDING IDENTICAL REVERSING GEAR MEANS FOR EACH OF SAID SEPARATE MEANS; A STEPLESSLY VARIABLE SPEED TRANSMISSION FOR DRIVING SAID REVERSING GEARING, INCLUDING A STEPLESSLY VARIABLE HYDRAULIC TRANSMISSION; A SERVOMECHANISM FOR ADJUSTING SAID HYDRAULIC TRANSMISSION, INCLUDING A RECIPROCABLE CAM; MEANS NORMALLY URGING SAID CAM IN ONE DIRECTION; A CONTROL ADAPTED TO BE CARRIED IN ONE HAND OF AN OPERATOR AND INCLUDING A PISTOL GRIP; A TRIGGER MOUNTED IN SAID CONTROL AND LOCATED IN A NEUTRAL POSITION RELATIVELY TO SAID PISTOL GRIP TO BE OPERABLE BY THE INDEX FINGER OF THE HAND HOLDING SAID CONTROL; MEANS ON SAID CONTROL FOR RENDERING EFFECTIVE SELECTED OF SAID REVERSING GEAR MEANS FOR CAUSING MOVEMEN OF A SELECTED OF SAID TABLE, SADDLE, HEAD AND SPINDLE; AND MEANS RENDERED EFFECTIVE WHEN SAID TRIGGER IS MOVED FROM ITS NEUTRAL POSITION FOR MOVING SAID CAM TO ACTUATE SAID SERVOMECHAMISM TO THEREBY CAUSE THE SELECTED TABLE, SADDLE, HEAD OR SPINDLE TO BE MOVED AT A RATE DEPENDING UPON THE POSITION OF SAID TRIGGER.

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