US3654818A

US3654818A - Universal milling and boring machines

Info

Publication number: US3654818A
Application number: US450466A
Authority: US
Inventors: Leo L Hengehold
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-04-23
Filing date: 1965-04-23
Publication date: 1972-04-11
Anticipated expiration: 1989-04-11

Abstract

The technical disclosure of the following specification is of a universal jig boring and milling machine for performing a wide variety of operations upon a workpiece mounted on the table of the machine. The machine''s speed of feed operation is selected by positioning of a feed turret carrying a gear train so that power from the principal power source is fed to the feed turret and through the portion of the gear train selected by positioning of the turret.

Description

United States Patent Hengehold [541 UNIVERSAL MILLING AND BORING MACHINES [72] Inventor: Leo L. Hengehold, 5963 Harrison Avenue, Miami Township, Hamilton County, Ohio 452| l [22] Filed: Apr. 23, 1965 [21] Appl. No.: 450,466

Related U.S. Appllcatlon Data [63] Continuation of Ser. No. 806,259, Apr. 14, 1959, Pat.

[52] U.S. Cl .,74/331 [5 l] Int. Cl Flh 3/08 [58] Field ofSearch .J4/353,331

[56] References Cited UNITED STATES PATENTS 2,499,193 2/1950 Lochman ..90/14 2,901,946 9/1959 Grabes ..90/14 2,604,019 7/1952 Malner ..90/17 [151 3,654,818 [451 Apr. 11,1972

2,619,879 121'1952 l-losae ..90/17 2,653,519 9/1953 Armitage etal... ..90/21 2,682,203 6/1954 Senn ..90/21 1,964,352 6/1934 Hazard ....74/353 2,688,257 9/1954 Hathaway ....74/353 2,690,246 9/1954 Kelleigh 1 92/66 2,727,610 12/1955 Frerer etal.. ....192/66 2,831,237 4/1958 Bannow... ....29/1.5 2,819,622 l/l958 Haxton ..74/353 Primary Examiner-Leonard H. Gerin Attorney-Pearce & Schaeperklaus [57] ABSTRACT The technical disclosure of the following specification is of a universal jig boring and milling machine for performing a wide variety of operations upon a workpiece mounted on the table of the machine. The machine s speed of feed operation is selected by positioning of a feed turret carrying a gear train so that power from the principal power source is fed to the feed turret and through the portion of the gear train selected by positioning of the turret.

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O MW www Sa 1 w if 0 H M. 2 mv m w74 Nww www M mw @Em .L www Kw NG UNIVERSAL MILLING AND BORING MACHINES This application is a continuation of my copending application Serial No, 806,259, filed April 14, 1959 now Patent No. 3,232,171.

This invention relates to machine tools and more particularly to a universal jig boring and milling machine.

An object of this invention is to provide a universal jig boring and milling machine.

Another object of this invention is to provide a machine of the above character having great versatility and large capacity for its size.

Another object of this invention is to provide a machine of the above character upon the table of which a workpiece may be mounted in fixed relation and milling and boring operations performed thereon from a wide variety of angularly rotated positions with no or minimum remounting of the work piece.

An object of this invention is to provide a machine of the above character in which the controls used frequently by the operator are grouped within convenient reach of the operator for ease in manipulation with minimum reaching effort.

Another object of this invention is to provide a machine of the above character having a base upon which a column rotatable about a vertical axis is supported, a saddle movable up and down the column, and carrying an elongate overarm for swinging about an axis perpendicular to the column axis and shiftable longitudinally of radii of the axis perpendicular to the column axis, a head carrier swingable about an axis parallel to the radius along which said overarm is longitudinally shiftable, a head rotatable about an axis extending radially from the axis of head carrier rotation, and a quill supporting a rotatable spindle and advanceable along an axis parallel to a radius of the axis of head rotation.

A further object of this invention is to provide a machine of the above character having a saddle supported on said base for reciprocation and a workpiece supporting table mounted upon said saddle for reciprocation relative thereto and transversely of the direction of reciprocation of said saddle.

A further object of this invention is to provide in a device of the foregoing character a power transmission unit supported on an angle plate forming part of the base, said power transmission unit comprising a motor, rapid traverse assembly, and feed turret.

A further object of this invention is to provide for a power transmission unit of the above character, a feed turret comprising a ring frame, a turret frame supported thereby for rotation, an input shaft supported for rotation coaxially in said turret frame, an input gear secured to said input shaft for rotation therewith, an output shaft supported for rotation about a fixed axis parallel to the axis of the input shaft, an output gear secured to the output shaft for rotation therewith, a plurality of like compound gears supported for rotation about respective axes in fixed relation to said turret frame and spaced radially from said input gear, said compound gears each having first and second sets of teeth disposed upon respective pitch circles of different diameter, the first set of teeth being adapted to drivingly engage the output gear when the axis of that compound gear is coplanar with the axes of the output gear and the input gear, a plurality of idler gears supported for rotation about respective axes which are in fixed relation to the turret frame, one of said idler gears being in continuous co-operative engagement with the input gear, each of said idler gears being in co-operative engagement with the first set of teeth of one respective adjacent compound gear and the second set of teeth of the other adjacent compound gear, whereby rotation of the input gear effects simultaneous corresponding rotation in like direction of the compound gears at differing speeds, and means for rotating the turret frame to index the same to support a desired one of said compound gears in meshing engagement with said output gear whereby said output shaft may be positively rotated with predetermined relation to the rotation of said input shaft and whereby re-indexing of the turret frame may be effected to alter the speed of rotation of the output shaft without altering its direction of rotation.

Another object of this invention is to provide a machine of the above character having a base, a saddle mounted for linear reciprocation on said base, a workpiece supporting table mounted on said saddle for linear reciprocation transversely of the line of saddle movement, a column supported for rotation about an axis perpendicular to the plane of table reciprocation, a column saddle movable along said column parallel to the axis thereof, a saddle plate supported by said column saddle for rotation about an axis perpendicular to the column axis, an elongated overarm extending through said saddle plate for longitudinal reciprocation and swingable in unison with said rotatable saddle plate, a head carrier supported by said overarm and swingable about an axis extending longitudinally of said overarm, a head supported by said head carrier for rotation about an axis extending radially of said head carrier axis, and a spindle supporting quill reciprocable in said head.

Another object of this invention is to provide a machine of the above character having a base, said base having a pre-assembled unit comprising an angle plate adapted to support an electric motor and associated feed and rapid traverse power transmission means in said base and to close the wall opening in said base through which said supported means are inserted as a pre-assembled unit.

Another object of this invention is to provide in a device of the above character having a stationary base, a rotatable column mounted thereon, a column saddle advanceable up and down the column, an overarm, an overarm saddle c0- operating with said overarm and secured in pivotal relation to said column saddle, said overarm being shiftable longitudinally in said overarm saddle, means for advancing said column saddle up and down said column and for |ongitudinally shifting said overarm in said overarm saddle comprising a saddle feed screw supported for rotation and against axial displacement relative to said column and in co-operative engagement with said column saddle, a rack secured to and extending longitudinally of said overarm, an overarm feed pinion supported in co-operative engagement with said rack, a worm pinion shaft supported in said column saddle for rotation in coaxial relation to said overarm saddle, means coupling said worm pinion shaft and said overarm feed pinion for related rotation, a worm wheel secured to said worm pinion shaft for rotation in unison therewith, a worn, means supporting said worm in co-operative engagement with said worm wheel, a rotatable feed shaft extending coaxially and slidably through said worm and parallel to the column axis, means coupling said worm to said feed shaft whereby rotation of said feed shaft effects corresponding longitudinal displacement of said overarm relative to said overarm saddle, a column pinion shaft supported in coaxial relation to said column for rotation and longitudinal reciprocation, a column pinion shaft shifter adapted to axially shift the column pinion shaft between first and second limit positions, means adapted to drivingly couple said column pinion shaft when in first limit position of axial displacement to said saddle feed screw, means adapted to drivingly couple said column pinion shaft when in a second limit position of axial displacement to said feed shaft, a rotatable column bevel gear bracket supported in coaxial relation to said column, a bevel gear pinion shaft supported by said bevel gear bracket, a pair of co-operating bevel gears respectively coupled to said column pinion shaft and said bevel gear pinion shaft and supported in co-operative relation to each other, a hand wheel bracket shaft supported by said base for rotation, means coupling said hand wheel bracket shaft and bevel gear pinion shaft for rotation in unison, whereby rotation of said hand wheel bracket shaft effects advancement of the column saddle along the column when the column pinion shaft is in the first limit position and longitudinal shifting ofthe overarm in said overarm saddle when the column pinion shaft is in the second limit position.

Another object of this invention is to provide in a device of the above character a worm supported for rotation about and against axial displacement along an axis fixed in relation to the column saddle, at least a portion of a set of worm wheel teeth being provided on the overarm saddle and adapted to cooperate with the worm whereby rotation of the worm effects angular movement of the overarm saddle relative to the column saddle facilitating precise angular orientation of the overarm.

A further object of this invention is to provide a device of the foregoing character having a base and a rotatable column supported thereon, said column having a skirt portion extending into said base, worm teeth on the skirt, a cartridge, a shaft journaled for rotation in said cartridge, a worm secured to said shaft, a hand wheel secured to said shaft, said cartridge, shaft, worm and hand wheel being adapted for insertion into cooperative relation to said base, said base being adapted to support said cartridge in co-operative relation to securing means with said worm in co-operative engagement with said worm wheel teeth, whereby rotation of said hand wheel effects angular rotation of the column.

A further object of this invention is to provide an overarm having a cylindrical portion extending from one end thereof, a plurality of recesses therein separated by integral portions each of worm wheel tooth form, a head carrier receiving said cylindrical portion and secured against displacement axially of said cylindrical portion, a shaft extending through said head carrier adjacent said cylindrical portion, a worm secured to said shaft for rotation therewith and thereby supported in cooperative engagement with said worm wheel tooth form portions, whereby rotation of said shaft effects corresponding swinging of said head carrier about said cylindrical portion and clamp means for locking said head carrier against swinging about said cylindrical portion.

A further object of the invention is to provide means for effecting power movement of the quill including a rotatable shaft mechanically coupled to said quill, a power rotatable first clutch member supported by said shaft and rotatable thereon, a second clutch member on said shaft, said second clutch member having a hub in which a pair of similar radially opposite apertures are provided, a pin extending diametrically through said shaft and extending into said hub apertures, whereby the second clutch member is coupled to said shaft for limited axial displacement therealong and for limited relative rotational movement of a magnitude related to the axial displacement along the shaft of the second clutch member relative to the first clutch member, and means for alternatively resiliently urging said first and second clutch members into engagement and positively into spaced non-engaging relation as desired.

Another object of this invention is to provide a device ofthe above character, characterized by the fact that each of Said apertures is bounded by two symmetrically disposed helical face portions which meet a diametrical axial plane of the shaft at an angle of l5 and a third radially disposed face portion which is closest to the first clutch member engaging portion of the second clutch member, said helical and radial face portions each being so disposed that line contact therewith may be made by said pin.

A further object of this invention is to provide in a device of the above character, a ram having an elongate, hollow central portion, an electric motor supported on an end of said ram, a head carrier supported on the other end of said ram, a head supported on said head carrier and having a rotatable spindle, power transmission means housed and supported in said ram, head carrier and head by means of which said ram supported motor may be coupled in driving relation to said spindle.

A further object of this invention is to provide a device of the above character characterized by the fact that said power transmission means includes a clutch-brake whereby said power transmission means is coupled to said motor or uncoupled from said motor and biased toward immobility.

A further object of this invention is to provide a device of the above character having power transmission means, which include a rotatable shaft through which power is delivered to said head and speed change mechanism, whereby the speed of said rotatable shaft by which power is delivered to said head may be selected.

A further object of this invention is to provide a device of the foregoing character having a head, a quill mounted for axial reciprocation in said head, a rotatable shaft mechanically coupled to said quill for reciprocating same, a power rotatable first clutch member supported by said shaft and rotatable thereon, a second clutch member on said shaft, said second clutch member having a hub in which a pair of similar, radially opposite apertures are provided, a pin extending diametrally through said shaft and extending into said hub apertures, whereby the second clutch member is coupled to said shaft for limited axial displacement therealong and for limited relative rotational movement of a magnitude related to the axial displacement along the shaft of the second clutch member relative to the first clutch member, a cup-like sleeve member receiving and encircling at least a portion of the hub of the second clutch member, resilient means co-operatng with said second clutch member and said cup-like sleeve resiliently urging said cup-like sleeve away from said first clutch member, an aperture in said sleeve, a crank adapted to co-operatively engage said sleeve and extending into said aperture, means for swinging said crank through a predetermined angle whereby said sleeve may be positively advanced toward said first clutch member to resiliently urge said second clutch member into engagement with said first clutch member to couple said power rotatable first clutch member and said rotatable shaft for rotation in unison and means adapted for actuation by advancement of said quill for positively shifting said cup-like sleeve away from said first clutch member, the hub of said second clutch member having stop means adapted to co-operate with said cup-like sleeve member whereby said second clutch member is shifted out of engagement with said first clutch member.

A further object of this invention is to provide first and second parallel shafts coupled for rotation in unison, a hand wheel, said hand wheel supported by and being adapted to rotate in unison with said first shaft, said second shaft being axially reciprocable, a power-driven clutch member mounted on said second shaft for relative rotation thereabout, a driven clutch member secured to said shaft for rotation in unison therewith and being advanceable into and out of engagement with said power driven clutch member by axial reciprocation of said second shaft, a reciprocable, non-rotatable collar through which said second shaft extends and to which said shaft is secured against axial relative movement, a plurality of rack teeth on said collar, a rack pinion supported for rotation and in engagement with said rack teeth and means for rotating said pinion whereby said second shaft may be axially shifted to couple and uncouple said shaft from driven relation to said power driven clutch member.

A further object of this invention is to provide for a machine tool having a linearly shiftable table in co-operative relation to an adjustable table gib, means for binding said gib, to lock said table in fixed relation to the support therefor, said means comprising an upper table clamp rod and a lower table clamp rod extending in parallel relation and transversely of the direction of table reciprocation, a rocker supported for rocking about an axis in fixed relation to said table and adapted to co-operatively and simultaneously engage a respective end of each of said upper and lower clamp rods, and means adapted to urge said upper clamp rod toward said rocker whereby said rocker may be swung to urge the lower clamp rod to clamp the gib against the table support.

The above and other objects and features of this invention will in part be obvious and will in part be apparent to those having ordinary skill in the art to which this invention pertains, from the following description, the accompanying drawings and the appended claims. ln the drawings:

FIG. 1 is a general view in perspective of a machine embodying my invention in what presently appears to be a preferred fomt, portions of the machine being broken away to illustrate various features thereof and other portions thereof being omitted for clarity;

FIG. 2 is a top plan view of the feed drive motor, rapid traverse and feed turret assembly, housed in the base of the machine illustrated in FIG. l, portions thereof being broken away to more clearly illustrate the structure and its operation;

FIG. 3 is a generally schematic view in vertical section of the feed turret gear train of the machine;

FIG. 4 is a fragmentary view in vertical section of a portion of the machine base, taken generally through the axis of rotation of the saddle feed or cross feed screw;

FIG. 5 is a fragmentary view in vertical section taken on the line V-V in FIG. 4;

FIG. 6 is a fragmentary view in vertical section taken transversely of the saddle and showing the saddle, saddle clutch shaft and associated clutch shifter mechanism for controlling the clutch through which power may be applied to the table feed screw rotating mechanism;

FIG. 7 is a fragmentary view in vertical section taken longitudinally of the saddle and showing the table feed screw and associated mechanism for manual and power rotation thereof;

FIG. 8 is a fragmentary view in horizontal section of a por tion of the column feed mechanism, including the manual means for actuating it and for controlling application of power thereto, some portions broken away being shown in dot-dash lines;

FIG. 9 is a view in vertical section taken along the line IX- IX in FIG. 8;

FIG. l is a view in generally vertical section of the lower portion of the column and adjacent portions of the base, portions thereof being broken away showing part of the column rotating means and part of the feed mechanism and shifter means;

FIG. Il is a partially schematic horizontal plan view in section taken generally along the line XI-XI in FIG. l0, parts thereof being broken away and showing some of the gears forming part of the column feed mechanism in co-operative relation;

FIG. 12 is a top plan view of the column, column saddle and overarm or ram, portions thereof being broken away to more clearly illustrate portions of the column, column rotating, column saddle, column saddle plate, column saddle plate rotating and overarm feed mechanism',

FIG. 13 is a view in generally vertical section of the ram and column saddle in co-operative relation to the column, column feed shaft and the saddle feed screw; i

FIG. 14 is a view in side elevation of the ram or overarm generally in section and partly broken away, showing the overarm motor and associated power transmitting mechanism;

FIG. l is a view in side elevation, partly in section of the head carrier in association with adjacent co-operating portions of the overarm and the head and associated portions of the mechanism for transmitting power from `the motor to the head.

FIG. I6 is a view in generally vertical section broken away to show the means by which power is supplied to the quill assembly for rotating the spindle and speed and direction change gearing forming part of the power feed for quill reciprocation;

FIG. I7 is a top plan view of the head, parts thereof being broken away to show the manual and power driven quill advancing or feed mechanism including the overload clutch and automatic kick-out;

FIG. 18 is a fragmentary view in front elevation partly in section of portions of the automatic kick-out mechanism shown in FIG. 17;

FIG. I9 is a fragmentary top plan view in section, partly broken away, showing the saddle feed kick-out mechanism;

FIG. 20 is a view in vertical section of the spindle, quill and associated portions of the head taken on a plane parallel to and in front ofthe central portion of FIG. I6;

FIG. 2l is a fragmentary top plan view, partly broken away, of a portion of the overarm or ram and the associated spindle speed in range selector;

FIG. 22 is a fragmentary top plan view, partly broken away, of a portion of the overarm or ram and the associated spindle speed range selector;

FIG. 23 is a fragmentary view showing details of the quill feed pinion shaft and the driven clutch hub coupled thereto by pin means;

FIG. 24 is a fragmentary top view in generally horizontal section, partly broken away, showing structural details of the table power feed kick-out mechanism;

FIG. 25 is a fragmentary view in front elevation of portions of the head and head carrier indicated by the arrows 25-25 in FIG. l5;

FIG. 26 is a fragmentary view in vertical section showing the means for shifting and locking the feed turret end frames in relation to the feed turret frame and determining the speed of rotation of the feed turret output shaft relative to the speed of rotation of the feed turret input shaft;

FIG. 27 is a fragmentary view in vertical elevation, partly broken away, showing means for precisely tilting the overarm or ram and rotating its saddle with respect to the columns; and

FIG. 28 is a somewhat schematic fragmentary view in front elevation, partly in section, of the quill pinion feed shaft clutch sleeve and co-operating sleeve shifter crank pin.

In the specification and accompanying drawings like reference characters indicate like parts.

In FIG. l ofthe drawing is shown a universal vertical milling and boring machine having a base or frame 50. An access opening is provided in wall 54 of base 50 and a cover or door 5l, hinged to base 50 at 52, is provided for closing same. Door knob 53 is provided for convenience in opening and closing door 5l and may be adapted to actuate door latching means (not shown) by which the door may be secured in the position shown in FIG. l. A second opening is provided in wall 55 of base 50 in a location substantially opposite door 5l. The opening in wall S5 is closed by an angle plate 56 (shown in FIG. 2) comprising a cover plate portion 57 which may be secured to wall 55 by any suitable means such as bolts, screws, or the like (not shown), and a bracket portion 58 formed integrally therewith. Bracket portion 58 is angularly related to cover plate portion 57 such that when cover plate 57 is secured to wall 55, closing the opening therein, bracket portion 58 projects substantially horizontally therefrom into the hollow interior of the base 50. Bracket portion 58 projects from cover plate portion 57 adjacent the lower edge thereof and supports the feed drive motor 59, the rapid traverse bearing bracket 60, and the mantel clock or feed turret 6l, which may all be mounted upon bracket portion 58 to form a unitary assembly adapted to be inserted through the opening provided in wall 55 incident to mounting and securing of angle plate 56 in position relative to base wall 55. Motor 59 may be mounted on bracket plate 58 in any suitable manner if desired, mounting means (not shown) facilitating adjustment of the tension in roller chain 70 may be utilized. Sprocket wheel 63 is mounted upon and keyed to motor shaft 62 for rotation in unison therewith. Set screw 64 is provided to preclude axial displacement of sprocket wheel 63 along motor shaft 62.

Rapid traverse bearing bracket 60 is secured to angle bracket portion 58 by bolts or other suitable means (not shown). Bracket 60 has three pedestal portions 65 for cooperatively supporting

antiffriction bearings

66 and 67 in coaxial alignment. Rapid traverse drive shaft 68 is journaled for rotation in bearings 66. Sprocket wheels 69, 7l are mounted on shaft 68,

keys

72 and 73 respectively serving to secure sprocket wheels 69 and 7l to drive shaft 68 for rotation in unison therewith. Chain 70 is trained in co-operative engaging relation over

sprocket wheels

63 and 69 such that operation of the motor 59 effects rotation of rapid traverse drive shaft 68 and the associated members mounted thereon.

Rapid traverse driving clutch plate 74 is mounted on drive shaft 68 for rotation in unison therewith. Drive shaft 68 may, as shown, have a collar or shoulder portion 76 adapted to cooperate with the adjacent bearing 66 and through which thrust loads imposed upon clutch plate 74 may be transferred to the rapid traverse bearing bracket 60. Clutch plate 74 has a central bearing 75 in coaxial alignment with rapid traverse drive shaft 68, as shown in FIG. 2. The rapid traverse driven shaft 77 is journaled for rotation in bearings 67 and 75, and is thus in coaxial alignment with shaft 68. A final drive sprocket wheel 78 is mounted on shaft 77 adjacent bearing 67 for rotation in unison with shaft 77. Sprocket 78 is secured against axial displacement along shaft 77 by means of taper pin 79 and cooperates with bearing 67 as is shown clearly in FIG. 2, to preclude axial shifting of shaft 77 toward shaft 68. Shifting of shaft 77 in the opposite direction, namely, away from shaft 68, is precluded by retaining ring 82 which engages spacing collar 80, which, in turn, co-operates with thrust washer 81 interposed between collar 80 and the adjacent bearing pedestal 65.

The feed clutch sprocket 83, mounted on shaft 77 adjacent retaining ring 82, is freely rotatable relative to shaft 77, but secured against axial displacement past retaining ring 82 toward collar 80 and by retainer ring 506 away from collar 80. Retainer ring 506 is partially received in groove 559 provided in shaft 77. Feed clutch sprocket 83 has clutch teeth 84 projecting axially therefrom and extending radially from adjacent shaft 77. Feed clutch 85 is mounted for reciprocation axially along shaft 77 into selective engagement with feed clutch sprocket 83 and in the alternative toward drive clutch plate 74 while continuously coupled to shaft 77 by key 86 for rotation in unison therewith. Feed clutch 85 has axially projecting clutch teeth 87 adapted to co-operate with the clutch teeth 84 of feed clutch sprocket 83, as shown in FIG. 2. When the

clutch teeth

84 and 87 are in co-operative engagement, feed clutch sprocket 83 rotates in unison with shaft 77. Adjacent the opposite end of feed clutch 85, driven clutch plate portion 88 is provided. As illustrated in FIG. 2, boss or hub 89 projects from clutch plate 88 toward clutch plate 74. A pair of clutch facings 90 and a clutch disc 91 therebetween may be mounted in annular encircling relation upon boss 89, with one ofthe facings 90 adapted for flatwise abutting engagement with an adjacent co-operating face of clutch plate 88 and the second clutch facing 90 adapted to co-operatively engage clutch plate 74. Retaining ring 92 may be provided for retaining the clutch facings 90 and clutch disc 91 in the assembled relation, as il lustrated in FIG` 2. Feed clutch 85 has a radially projecting rib 93 adapted to facilitate shifting of feed clutch axially of shaft 77. Shifter ring 94 has an internal annular channel or groove adapted to co-operatively receive the radially projecting rib 93. The rib 93 is free to rotate in that groove relative to ring 94 while axial displacement of rib 93 relative to ring 94 is precluded. A shifter crank 95 is mounted upon pivot post 96 projecting upwardly from rapid traverse bearing bracket 60. The crank arm 95 has a pair of form arms 97 in co-operation with shifter ring 94, whereby swinging of crank arm 95 about pivot 96 effects reciprocation of shifter ring 94 and feed clutch 85 axially along shaft 77 to the desired one of three positions "feed", neutral, or rapid traverse". To effect shifting of feed clutch 85 from one to another of the three positions it is necessary to swing crank 95 about pivot 96. Link 103 is co-operatively connected to crank 95 by pivot pin 104 and to rapid traverse control lever 98 by pivot pin 102, as shown in FIG. 1. The lever 98, as shown in FIG. 1, may be pivotally secured to bracket 99 by pivot pin 100. The bracket 99 is integral with or secured in fixed relation to base 50 as shown in FIG. l. If desired, suitable biasing means (not shown), such as a spring, may be provided in co-operative relation with the means for moving feed clutch 85, for biasing feed clutch 85 toward one of the three positions feed, neutral, or rapid traverse". Clutch 85 is preferably biased toward neutral position. l provide a friction latch in co-operative relation to lever 98. A screw 159 (shown in FIG. 1) is disposed in and threadedly engages the walls of a bore extend ing through lug 101 of bracket 99. Screw 159 is in spaced, parallel relation to pivot pin 100. A pair of depressions (not shown) are provided in lever 98, one thereof registering with the bore in which screw 159 is disposed when lever 98 is in "rapid traverse" position, and the other when lever is in feed" position. A latch member, such as a hard sphere, is provided and movable in the bore in lug 101. A compression spring is disposed between screw 159 and the sphere and loaded as desired by appropriate adjustment of screw 159 so as to frictionally secure lever 98 in either feed" or rapid traverse" position and thus prevent movement of lever 98 and clutch toward neutral position, the position toward which clutch 85 is biased. Thus, the friction latch means adjustable by screw 159 serves to secure lever 98 in feed" or "rapid traverse" positions while the means biasing clutch 85 serve to bias lever 98 toward and retain it in neutral position at other times.

When feed clutch 85 is in feed" position, as shown in FIG. 2, it is in engagement with feed clutch sprocket 83 driven through feed turret 61 at a predetermined reduced speed, as will be explained subsequently. Angular rotation of shaft 77 in a direction opposite to the direction of angular rotation of motor shaft 62 and rapid traverse drive shaft 68 is thereby effected.

When feed clutch 85 is in "neutral" position, disengaged from feed clutch sprocket 83 and from clutch plate 74, shaft 77 is not subjected to rotation effecting forces being transmitted from motor 59 (except those of ineffective magnitude resulting from rotation of bearing member 75 relative to shaft 77).

When feed clutch 85 is in rapid traverse" position, driven clutch plate 85 is adjacent and coupled to clutch plate 74 by the interposed clutch facings and disc 91 compressed therebetween to e'ect unison rotation of

shafts

68 and 77. Thus, in shifting of feed clutch 85 from "feed" to rapid traverse" position, the speed of rotation of shaft 77 is increased and its direction of rotation is reversed.

Feed turret 61 has a frame or body member 105 mounted upon bracket portion 58 in spaced relation to rapid traverse bracket 60 and motor 59, as shown in FIG. 2. Frame or case member 105 is of generally ring-shape and has a radially lnwardly projecting flange 108 adjacent one end thereof. Retaining ring 109 secured to case 105 serves to form a retaining flange opposite flange 108 at the second end of case 105. A rotatable assembly or turret portion is mounted in the frame 105 between flange 108 and retaining ring 109. The turret asv sembly has round, disc-like end frames 106 and 107 secured in parallel spaced relation to each other by means of turret studs 110. Each of the turret studs 110, as shown in FIG. 2, has a central cylindrical shoulder portion 111 having radial end faces from which threaded stud portions l 12 of smaller diameter extend coaxially. The end faces of shoulder portions 111 are disposed between and in co-operative abutment with the inwardly facing, opposed faces of

end plates

106 and 107, thereby maintaining the end plates in parallel, predetermined spaced relation. Nuts 113, in threaded co-operative relation with threaded stud portions 112, are drawn up to clamp the

respective end plates

106 and 107 firmly against the radial end faces of the shoulders 111.To effect angular rotation of the rotatable turret assembly, of which

end plates

106 and 107 constitute the principal frame portions, into a desired position within and relative to feed turret frame 105, a worm 124 and worm wheel 128 are provided. Worm 124 is mounted upon worm drive shaft 125 to which it is coupled by key 126 for rotation in unison therewith. Means (not shown) are provided to secure worm 124 against movement longitudinally of shaft 125. Shaft 125 is journaled for rotation in support bearings which may be provided in flxed relation to feed turret body 105 and frame 50 as shown in FIG. 26. Shaft 125 is thus supported for rotation about a predetermined axis and secured against axial displacement along that axis by means such as

stop collars

160, 161, respectively secured to shaft 125 by

taper pins

162 and 163.

Collars

160, 161 co-operate with an intervening portion of frame 50, as shown in FIG. 26. Worm 124 is thus rotatable in a predetermined location relative to case or frame member 105 and in engagement with teeth 129 of worm wheel 128. End plate 106 is provided with an axially, outwardly extending, annular spacing collar or boss 127 which is secured in fixed relation thereto and to worm wheel 128 by any suitable means, such as keys, welds, screws, bolts, or the like, not shown. Worm wheel 128 is mounted in coaxial relation to end

plates

106 and 107. Worm wheel 128 has radially projecting peripheral teeth 129 adapted to cooperatively engage thread 130 of worm 124. Rotation of worm 124 effects rotation of the rotatable assembly including

end plates

106 and 107 within turret case or frame 105.

As shown most clearly in FIG. 2, a pair of aligned axial bores are provided in

end plates

106 and 107 and bearing inserts 114 are provided therein. Turret input or driving shaft 115 is journaled for rotation in bearings 114. Turret input or driving sprocket 116 and turret input or driving gear 117 are mounted upon and respectively coupled to shaft 115 for rotation in unison therewith by keys 118 and 119, and set screws 120 and 121. As shown in FIG. 2, grease or

oil seals

122 and 123 may be provided in sealing co-operation with

end plates

106 and 107, respectively, and shaft 115.

Power from motor 59 may be applied to turret input or drive shaft 115 through sprocket 63, chain 70, sprocket 69, shaft 68, sprocket 71, turret drive chain 116C, and driven sprocket 116. Thus, whenever motor 59 is in operation, the turret drive shaft 115 rotates in the same direction as motor shaft 62 and the turret driving gear 117 rotates in unison with shaft 115 to drive the turret gear train. The details and arrangement ofthe power transmitting gear train of turret 61 are shown most clearly in the generally schematic view, FIG. 3.

As shown in FIG. 3, the rotatable turret 6l has a plurality of shafts which are parallel to studs 110 which serve as shafts. As previously explained, turret driving shaft 11S extends axially through

end plates

106 and 107. An outer row of non-rotating shafts, ten in number, are regularly spaced and equidistant from the axis of shaft 1S. As indicated, five of these shafts are the turret studs 110, specifically the central portions 111 thereof. The alternate, intervening shafts in the outer circle comprise pins 131 co-operatively supported by

end plates

106 and 107, in which respective pairs of aligned apertures are provided. Suitable means, such as set screws 133 (FIG. 2) may be provided in threaded co-operation with one of the end plates, such as plate 106 and each adapted to preclude axial shifting of one of the shafts 131. Shafts 131 may be hardened dowel pins of the same diameter as the shoulder portions 111 of turret studs 110. Ten compound gears 132, severally further identified by the reference characters FIRST, SECOND, THIRD, FOURTH, FIFTH, SIXTH, SEVENTH, EIGHTH, NINTH, and TENTH, respectively, are journaled on the

shafts

131 and 110, as shown in FIGS. 2 and 3, for free rotation relative to the respective shafts. Each of the compound gears 132 comprises a first or larger diameter portion having twenty teeth 13S on pitch circle 134. The second or smaller diameter portion of compound gear 132 has fourteen teeth 136 on pitch circle 137. In assembling the turret, the compound gears 132 are placed on the

shafts

110 and 131 so that when viewed as in FIG. 3, the portion of gear 132 having pitch circle 134, is remote from the observer on every other shaft, for example, on all shafts 131, while those on the intervening shafts 110 are placed with the portion having the pitch diameter 134 nearest to the observer. To further illustrate this point, assume that the sectional view of the turret 61 forming part of FIG. 2 is taken along the section line indicated in FIG. 3, as II-Il. The compound gears 132 journaled for rotation upon shafts 131 are placed in the position in which the gear 132 on shaft 131 is illustrated in FIG. 2. All of the gears 132 journaled for rotation on the shafts 110 are in a position corresponding to the position of gear 132 on shaft 110 in FIG. 2. Thus, on each shaft 131 the portion of compound gear 132 having pitch circle 134 is adjacent end plate 107 and the portion having pitch circle 137 is adjacent end plate 106. The compound gears 132 journaled for rotation upon the turret studs or shafts 110 are placed with the portion of the gear having the pitch circle 134 adjacent end plate 106 and the portion having the pitch circle 137 adjacent end plate 107. The portions of compound gears 132 adjacent each of the end plates are alternately of large and small pitch diameter. The gears 132 do not mesh with each other. lt will be noted that inasmuch as each of the shafts in the outer circle of shafts, namely,

shafts

110 and 131, are radially spaced an equal distance from the axis of shaft 115, the teeth on the portion of each compound gear 132 lying along the respective pitch circle 134 will properly mesh with the teeth 138 lying on pitch circle 139 of turret output gear 140, when the axis of its

shaft

110 or 131 is coplanar with the axial plane of

shafts

115 and 141, shaft 141 being the shaft upon which gear 140 is mounted and to which it is keyed by key 142. It is to be noted that gear 140 has an axial dimension substantially equal to that of compound gear 132. As shown in FIG. 2, shaft 141 is journaled for rotation in turret frame or case 105, and turret output sprocket 143 is mounted thereon for rotation in unison therewith in co-operative relation to frame 105. Key 144 cooperatively couples shaft 141 and sprocket 143 while set screw 145 serves to preclude axial displacement of shaft 141 relative to output sprocket 143. A stop collar 146 threadedly engages shaft 141 adjacent its end remote from output sprocket 143. Collar 146 may be rotated relative to shaft 141 to position it for co-operative engagement with frame 105, collar 146 and sprocket 143 being spaced to limit longitudinal displacement or end play of shaft 141 to a magnitude falling within tolerance limits. Set screw 146o is provided to lock stop collar 146 in such position of adjustment longitudinally of shaft 141.

Turning again to the gear train of the turret, a driving idler gear 147 is journaled for rotation upon shaft 148 positioned so that teeth 149 of idler gear 147 are in constant proper mesh with turret input or driving gear 117, the teeth 136 lying on pitch circle 137 of compound gear FIRST 132 and the teeth 135 lying upon pitch circle 134 of compound gear SECOND 132. As shown, turret driving gear 117 has 2l teeth, and idler gear 147 has I6 teeth. The idler gear 147 meshes with the I4 teeth on pitch circle 137 of the compound gear FIRST 132 and the 20 teeth on pitch circle 134 of the compound gear SECOND 132. Idler gear lst 150,joumaled for rotation upon idler shaft 1st 151, has 14 teeth 152 on pitch circle 153. The teeth 136 lying on pitch circle 137 of compound gear SECOND 132, mesh in driving relation with the teeth 152 lying on the pitch circle 153 of idler gear lst 150. The teeth 152 of idler gear 1st 150 also mesh with the teeth 135 lying on pitch circle 134 of compound gear THIRD 132. In a similar manner compound gear THIRD 132 drives idler 2nd 150 which, in turn, drives compound gear FOURTH 132 which drives an idler 3rd 150 which, in turn, drives the compound gear FIFTH 132 and the latter drives an idler 4th 150, which, in turn, drives the compound gear SIXTH 132, which, as shown in FIG. 3, is in mesh with and drives turret output gear 140. Each of the subsequent compound gears SEVENTH 132, EIGHTH 132, NINTH 132, and TENTH 132 is driven through a respective meshing idler 5th 150, 6th 150, 7th 150, or 8th 150 by the preceding compound gear 132 in the train, and in turn, drives the following compound gear through another idler gear 150. Thus, the compound gears 132 and the turret driving gear 117 all rotate in like direction, as shown by the arrows in FIG. 3. For purposes of illustration, an arrow has been placed on the representation of each of the gears adjacent the portion which is in co-operative engagement with another gear in the gear train illustrated in FIG. 3 to indicate the direction of rotation of each gear corresponding to the indicated particular direction of rotation of each of the other gears in the trainV The arrows are not intended to indicate that the respective gears rotate in only one direction. The feed drive motor 59 is preferably one which may be operated to drivingly rotate its shaft 62 in clockwise or in counter clockwise direction, as previously explained. Reversal of the direction of rotation of the motor shaft 62 will effect a corresponding reversal of the direction of rotation of any particular gear in the gear train illustrated in FIG. 3. There are eight idlers 150 respectively, further designated lst, 2nd, 3rd, 4th, 5th, 6th, 7th, and 8th. Each idler 150 is journaled for rotation on a respective shaft 151. The axes of shafts 151 are equally spaced radially from the axis of shaft 115 and each is angularly spaced 36 of arc from the shaft of 1st idler 150 as shown in FIG. 3. Further, the idlers 150 are of an axial dimension no greater than one-half the axial dimension of gears 132. The even numbered, i.e., 2nd, 4th, 6th, and 8th idlers 150 being positioned adjacent end plate 106 similar to the positioning of driving idler 147 in FIG. 3. The oddnumbered, i.e., lst, 3rd, 5th, and 7th idlers 150, like 5th idler 150, are disposed adjacent end plate 107 as shown in FIG. 3.

Rotation of worm 124 in cooperative relation with the teeth of worm wheel 128 effects rotation of

end plates

106, 107 and the portions of the assembly supported thereby relative to the frame or turret case 105 in which the end plates are mounted. Thus, by appropriate rotation of worm 124 any desired compound gear 132 may be moved into appropriate meshing engagement with turret output gear 140, teeth 135 of the former co-operating with teeth 138 of the latter when the axes of their shafts are coplanar with the axis of shaft 115.

The compound gear FIRST 132 rotates faster than SECOND 132 and each succeedingly numbered gear 132 rotates more slowly than the one of next lower number and the TENTH gear 132 rotates lowest of all of the gears 132. Further, all gears 132 rotate in like direction at any given time and shifting the turret to engage a different gear 132 with gear 140 alters the speed of rotation of gear 140, but not its direction of rotation. All gears 132 shown in the drawing rotate at a speed such that drive shaft 77 is, through turret output sprocket 143, turret output drive chain 154, feed clutch sprocket 83, and feed clutch 85, driven at a slower speed of angular rotation and in opposite direction to the rotation of shaft 68, when feed

clutch teeth

84 and 87 are in co-operative engagement.

From the foregoing description, it may be noted that when motor shaft 62 rotates in a given direction, which may be referred to as clockwise rotation, the final drive sprocket 78 will rotate in like direction when the rapid traverse

clutch having plates

74 and 88 is engaged and

shafts

77 and 68 will rotate in unison. Further, if shaft 68 is rotated at the same speed and in the same direction when the feed drive clutch 85 is engaged with feed clutch sprocket 83, namely, when

teeth

87 and 84 are in co-operating relation, final drive sprocket 78 will rotate more slowly in the opposite direction, at any one of ten speeds, corresponding to the particular compound turret gear 132 which is then in driving relation to turret output gear 140. ln order that the operator may conveniently and positively move any desired compound turret gear 132 into driving relation to turret output gear 140, turret indexing means are provided. As shown in FIG. 26, the turret indexing means has a crank handle 164 secured to shaft 165 for rotation in unison therewith. Shaft 164 is supported for rotation in frame 50. Stop

collars

166, 167 are secured to shaft 165 by taper-pins 1660, 167:1, respectively, and co-operatingly engage frame 50 to preclude axial shifting of shaft 165. Transfer shaft 336 is supported for rotation in bearing bracket 337 secured in fixed relation to frame 50 and feed turret frame or body 105. Universal coupling 253 connects

shafts

165 and 336 for rotation in unison. A pair of

bevel gears

351, 352 are respectively secured to

shafts

336 and 125 by which they are supported and with which they rotate in unison while in co-operative meshing engagement. Thus swinging of crank 164 effects corresponding rotation of worm 124 and turret end frames 106, 107 and the structure supported thereby to move compound gear 132 relative to gear 140. Crank handle 164 has one knob 375 secured to a pin 376 supported for axial reciprocation in crank handle 164 in spaced parallel relation to shaft 165 and spring biased to advance toward guard 337 secured to frame 50. Pin 376 is received in an indexing aperture in guard 377 to lock crank handle 164 against rotation in a position corresponding to co-operative engagement of one of the compound gears 132 with turret output gear 140. Thus, to rotate turret end frames 106, 107 one-tenth of a revolution and move one compound gear 132 out of engagement with gear 140 and an adjacent compound gear 132 into mesh with turret output gear 140, pin 376 may be retracted, disengaged from guard 377, crank 164 swung through one revolution, and pin 376 reengaged in the aperture in guard 377. As shown in FIG. 26, a

cup or drumshaped dial 378 is supported for rotation on shaft between crank 164 and frame 50. A dial driving gear train is housed in the dial 378 and comprises a shaft gear 379 secured on shaft 165, at least one idler or transfer gear 417 supported by stub shaft 418 supported by frame 50, and inwardly projecting teeth 419 provided on dial 378. The gear train represented by

gears

379, 417 and 419 is adapted to rotate dial 378 one-tenth of a revolution for each revolution of shaft 165. The cylindrical surface 378e of dial 378 has appropriate indicia provided thereon, for example, notations of the ten different speeds of table feed, located on the dial with respect to dial position corresponding to the particular position of the end frames 106, 107. Guard 377 serves with frame 50 to bound a dial viewing aperture through which the appropriate indicia of table feed speed on dial 378 is visible when a particular compound gear 132 is positioned in engagement with gear 140, and crank 164 is locked against rotation by engagement of pin 376 with guard 377, as shown in FIG. 26.

As shown in FIG. 2, final drive sprocket 78 is in constant operative engagement with final drive chain which, as shown, may be a three-strand silent roller chain. Chain 170 is also trained in driving relation to and over driven feed sprocket 171 (FIG. 4) and column feed sprocket clutch 172 (FIG. 8).

As shown in FIG. 4, horizontal portion 173 of frame 50 supports inside kickout bracket 174 secured thereto by suitable means, such as screws or bolts 175. A pair of aligned bearing sleeves or

bushings

176 and 177 are respectively mounted in apertures provided in inside kickout bracket 174 and the front wall of frame 50. Feed shaft 178 is journaled in

bearings

176 and 177 for angular rotation and as shown may extend through suitable oversize apertures provided in portions of frame 50 through which it extends as at 179. Driven feed sprocket 171 mounted upon feed shaft 178 is secured thereto for rotation in unison therewith by means such as taper pin 180. Sprocket wheel 171 may also co-operate with bearing sleeve 176, or other suitable thrust bearing member cooperating with inside kickout bracket 174 for limiting axial movement of feed shaft 178 longitudinally toward inside kickout bracket 174. To preclude axial movement of feed shaft 178 in the opposite direction, namely, away from bracket 174, feed shaft stop collar 181 may be secured in fixed relation to feed shaft 178 by suitable means such as set screw 182 for co-operative engagement with frame 50 or other suitable thrust bearing surface as shown in FIG. 4. Feed gear 183 is also mounted upon feed shaft 178 and secured thereto by means such as taper pin 184 for rotation in unison therewith. As shown in FIG. 4, a transfer or idler shaft 185 may be provided in spaced parallel relation to feed shaft 178 and journaled in

sleeve bearings

186 and 187 mounted in suitable apertures provided in frame 50. Stop collar 188 and idler gear 189 are mounted upon idler shaft 185 and by

set screws

190 and 191 are respectively secured to that shaft 185 for rotation in unison therewith. As shown in FIG. 4, the collar 188 and idler gear 189 may be secured to shaft 185 in spaced positions to substantially preclude axial shifting of the shaft relative to frame 50. Idler gear 189 is in constant mesh with and driven by feed gear 183. Idler gear 189, in turn, is in continuous driving engagement with feed clutch gear 192. Feed clutch gear 192 is mounted upon inner telescoping shaft 193, key 194 and set screw 195 serving to lock them together for rotation in unison while precluding axial displacement of one relative to the other. Inner telescoping shaft 193 is journaled for rotation in bearings 196. As shown in FIG. 4, a collar or washer 197 may be interposed between an annular shoulder 169 on shaft 193 and on opposed radial face of bearing 196 to preclude axial displacement of the inner telescoping shaft 193 toward the left of the position in which it is shown in FIG. 4. In a similar manner, feed clutch gear 192 has a radial face adapted to co-operate with an opposed radial face of the adjacent or second bearing 196 precluding axial displacement of telescop ing shaft 193 toward the right of the position in which it is

Claims

1. For a power transmission unit, a feed turret comprising a ring frame, a turret frame supported thereby for rotation, an input shaft supported for rotation coaxially in said turret frame, an input gear secured to said input shaft for rotation therewith, an output shaft supported for rotation about a fixed axis parallel to the axis of the input shaft, an output gear secured to thE output shaft for rotation therewith, a plurality of like compound gears supported for rotation about respective axes in fixed relation to said turret frame and spaced radially from said input gear, said compound gears each having first and second sets of teeth disposed on respective pitch circles of different diameter, the first set of teeth being adapted to drivingly engage the output gear when the axis of that compound gear is coplanar with the axes of the output gear and the input gear, a plurality of idler gears supported for rotation about respective axes which are in fixed relation to the turret frame, one of said idler gears being in continuous co-operative engagement with the input gear, each of said idler gears being in co-operative engagement with the first set of teeth of one respective adjacent compound gear and the second set of teeth of the other adjacent compound gear, whereby rotation of the input gear effects simultaneous corresponding rotation in like direction of the compound gears at differing speeds, and means for rotating the turret frame to index the same to support a desired one of said compound gears in meshing engagement with said output gear whereby said output shaft may be positively rotated with predetermined relation to the rotation of said input shaft and whereby re-indexing of the turret frame may be effected to alter the speed of rotation of the output shaft without altering its direction of rotation.

2. A feed turret comprising a main frame, a turret frame supported by the main frame for rotation about an axis, a second shaft supported by the main frame adjacent the turret frame and for rotation about an axis parallel to the axis of turret frame rotation, a second gear supported by said shaft for rotation in unison therewith, a plurality of duplicate compound gears each having two sets of teeth respectively on a large pitch circle and a small pitch circle, said compound gears being supported in regular spaced relation for rotation about parallel axes spaced equal radial distances from said turret frame axis and with the teeth on the large pitch circle thereof engageable with said second gear, a first shaft supported for coaxial rotation in said turret frame, a first gear secured to said first shaft, a coupling gear meshing with teeth of said first gear, the teeth on the small pitch circle of one compound gear and the teeth on the large pitch circle of an adjacent compound gear, a plurality of idler gears each meshing with teeth on the small pitch circle of a respective adjacent compound gear and drivingly meshing with teeth on the large pitch circle of a second respective adjacent compound gear, said compound gears being coupled in train by said idler gears for simultaneous rotation at respective unlike speeds, means for indexing said turret frame in said main frame to place the axes of rotation of the first gear, second gear, and a desired one of the compound gears in coplanar relation whereby the first and second gears are connected by turret frame supported gears for predetermined opposite related rotation at a ratio of rotation corresponding to the compound gear engaging the second gear.

3. For a machine tool, a speed change and rotation reversing feed turret comprising a fixed frame, a pair of turret end frames, a plurality of fixed shaft members joining said turret end frames in spaced, parallel, coaxial relation to form a turret frame, a first shaft supported by the turret end frames for rotation in coaxial relation to the turret frame, a first gear secured to said first shaft for rotation in unison therewith, a plurality of compound gears, each compound gear having one set of teeth on a large pitch circle and another set of teeth on a small pitch circle, each compound gear supported by a respective fixed shaft for rotation about a respective axis, said axes of compound gear rotation being parallel to and equally spaced radially from said rotatable first shaft, and regularly spaced from each other, said compound gears Being arranged in succession adjacent the periphery of the turret such that any two adjacent compound gears have respective sets of teeth adjacent one turret end frame and said sets of teeth are on respective pitch circles of unlike diameter, a driving idler gear in meshing engagement with said first gear and teeth on the small pitch circle of one compound gear and teeth on the large pitch circle of an adjacent compound gear, a plurality of idler gears each journaled for rotation on a respective fixed shaft and supported in meshing engagement with two respective adjacent compound gears coupling same for related rotation, a second shaft supported by said fixed frame for rotation about an axis parallel to said first shaft, a second gear secured to said second shaft for rotation in unison therewith, said second gear being adapted for co-operative meshing engagement with the set of teeth on the large pitch circle of a compound gear the axis of which is between and coplanar with the axes of the first and second shafts, and means for indexing said turret to co-operatively engage any desired one of said compound gears with said second gear whereby said first and second shafts may be coupled for related rotation at a ratio determined by the position in which the turret frame is indexed relative to the fixed frame.