US2118967A

US2118967A - Cutter grinder

Info

Publication number: US2118967A
Application number: US748630A
Authority: US
Inventors: Frank W Curtis
Original assignee: Kearney and Trecker Corp
Current assignee: Kearney and Trecker Corp
Priority date: 1934-10-17
Filing date: 1934-10-17
Publication date: 1938-05-31
Anticipated expiration: 1955-05-31

Description

i May 31, 193s. w CURWS A 2,118,967

CUTTER GRINDER Filed Oct. 17. 1934 2 Sheets-Sheet l Fig. l

)g INVENTOR- ATTORNEY F. W. CURTIS CUTTER @BINDER May 31, l938.

Filed oct. 17, 1954 2 sheets-sheet '2 Patented Mayl3l, 1938 I UmuD-STATES CUTTER dimmen Frank W. Curtis, Wauwatosa, Wis., assigner to Kearneyv & Trecker Corporation, West Allis,

Wis.

Application october 11, 1934,- serial No. 748,630

Claims. (Cl. 51-125) This invention relates generally to machine toolsand more particularly to. grinding machines.

It is an object of the invention to provide a grinding machine of a type particularly adapted 5 for grinding milling cutters having improved rigidity of support of the cutter to be ground and -the grinding wheel and an improved relationship of supports for relative adjustment and for relative grinding movement of the cutter and wheel.

A further object is to improve thel mounting of the grinding wheel and its driving means, particularly in a manner to avoid or minimize distortion or displacement which might disturb the desired relationship of the grinding Wheel and the cutter during the grinding operation, and in a manner to avoid vibration or chatter.

A further purpose is generally to simplify and .improve the construction and operation of cutter grinders and especially to provide an` improved supporting structure for the grinding `wheel spindle and the cutter carrying spindle of a cutter grinder, and still other objects and adand claims herein.

The invention consists of the construction and combination of partsv as herein-illustrated and explained, andin such modication thereof as may be equivalent to the structure set forthV in and dened by the claims.

The same reference characters have been umd to designate the same parts throughout the drawin-gs and description.

In the drawings: 3 5 Fig. 1 is a view in righthandside elevation oi a grinding machine in which the invention is incorporated.

Fig. 2 is an enlarged partial section and elevational view of the same machine taken along line 2-2 in Fig 1.

Fig. 3 is a view in longitudinal section takenl along line 3--3 in Fig. 2, showing a portion of the lower structure. t

Fig. 4 is a view in cross section taken along line 4-4 of Fig. 1. s

Thecutter grinding machine comprises a base I upon which is mounted a cutter supporting unit generally denoted by numeral 2, and a grinding wheel unit generally denoted by numeral 3. Supporting unit 2 provides a rotatable cutter carrying spindle `4 which at the one end is provided with a hand wheel 5 for rotation thereof, and at the other end is provided with an exposed portion upon which the cutter to be ground is mountedA for rotation coaxial with the spindle. Wheel vantages will be apparent from the description' unit 3 provides a grinding wheel spindle 6 upon which is mounted the rotor of van electric motor generally denoted by the numeral 1, and an abrasive grinding wheel 8 xed to the front end of the spindleadjacent to the cutter support.

' The cutter supporting unt 2 includes various relatively movable supports as follows: slidably guided on base I for reciprocatory movement in a path transverse to the axis of wheel spindle 6 is a cutter supporting slide or support 9 upon which a cutter carrying bracket or support I0' is mounted to be adjustable angularly about a vertical axis. Support I0 carries a cutter spindle support II slidably guided for vertical adjust-' ment, in which the horizontally disposedcutter carrying spindle 4 is rotatably mounted. Support 9 may be moved by the means of a hand crank, not shown, applied to the squared end of screw I2 which engages a nut I3, and may be clamped in anyposition of adjustment by a clamp screw I4. Support I0 may be rotated by the means of a' crank, not shown,'applied to the squared end 'of a shaft I5, which turns a worm I6, engaging a Worm wheel I1 fixed on the lower end of the support as best shovm in Fig.. 4, and may be clamped in any position of adjustment by the means of T-bolt-s I8. Support II may be adjusted vertically by the means of a hand crank, not shown, appliedl to the squared end of a screw 20. which engages with a nut 2 I, and may be clamped in any position of adjustment by the means of a -T-bot 22. The spindle 4 may be rotated, as previously noted, by the hand wheel 5. This serves to turn the cutter mounted at the other end of the spindle in a step-by-stepOmotion to present the diierent teeth of` the cutter to thegrinding.

, Wheel successively for sharpening. To locate the individual teeth in the proper position of rotation there is provided a tooth rest 23 4mounted for universal movement and adjustment about a rod 24 which in turn is pivoted in'a member 25 slidably adjustable on a member 26 fixed with the support II, the memberl 23 being clampable in any position of its adjustment by anyvsuitabvle means such as the bolts and nuts shown.

Abrasive wheel unit 3 includes various relatively movable supports as follows: Slidably guided on base I for movement in a direction at right angles to the path of the cutter support 9 is a rst support or grinder supporting slide 21 `upon which a second support or bracket 28 iS.

grinding wheel spindle carrier or third support 30. 'I'he support 21 may be moved by a hand wheel 3| xed on a screw 32 engaging a nut 33 and may be clamped in any position of adjustment by the means of a screw 34 operating similarly to the clamp screw |4. 'I'he support 28 may be reciprocated by a hand wheel 36 xed on a shaft 31 upon which is also fixed a spiral pinion 38 engaging a rack 39 on the lower surface of the second support 28, as shown in Fig. 3. It is this hand wheel 36 which is normally used for traversing the grinding wheel 8 relative to the cutter mounted on spindle 4. The support 30 may be manually shifted about the pivot 29 by grasping the support and shifting it bodily, but for ne adjustments there is provided supplemental adjusting means best shown in Fig. 2 including a screw member 40 pivoted on a clamping bolt or stud 4| xed in the support 3D and which works in an arcuate slot 42 in the support 28. Screw 4|) is threaded and is provided with a hand nut 43 bearing on an ear or lug 44 fixed with support 28. As the hand nut 43,15 turned the support 30 is moved in the one or the other direction about pivot 29. Support 30 maybe clamped in any position of its pivotal adjustment by a nut 45 on the stud 4|, a similar clamp stud 46 and nut 41 being provided at the other side of the support. The supporting arrangement is such that universal adjustment is provided between a cutter being sharpened and a cooperating grinding wheel by mechanism having only four successive pairs of relatively movable bearing surfaces interposed between said cutter carrying spindle and said base, and likewise only four successive pairs of relatively movable bearing surfaces interposedbetween said grinding wheel spindle and said base.

The third support 30 is formed in two pieces,

there being a main portion or member 48 and a removably attached motor housing portion or member 49. The portion 48 carries a front antifriction bearing 50 and an intermediate antifriction bearing 'I'he portion 49 carries a rear anti-friction bearing 52. 'I'he front bearing 50 includes aninner race 531 shouldered against an enlarged portion of spindle 6 at 54, an outer race 55 shouldered against the support member 48 at 56, there being a plurality of interposed anti-friction ball elements 51, the bearing being adapted to restrain both rearward axial and lateral movements of the spindle. Theintermediate bearing 5| includes an inner race 58 which is slidably fitted to spindle 6, an outer race 59 which is shouldered against support member 48 at 60, and a plurality of interposed anti-friction ball elements 6|, this bearing being adapted to restrain both forward axial and lateral movements of the spindle. The inner race '58 may be adjusted along spindle 6 by the means of a nut 62 threaded on the spindle and the form of thevarious races and interposed anti-friction ball elements of the bearings 5II, 5| is such that adjustment of nut 62 serves to remove all slack in both these bearings and thereby to tix Athe spindle 6 against axial movement in either direction and against lateral movement at either end. A slight further tightening of nut 62 sets up an initial or preloaded condition of each of' the bearings 50 and 5|', which serves to minimize or prevent any displacement of the spindle as the grinding load increases or decreases and to prevent'chatter or vibration of the grinding wheel. 'I'he rear bearing 52.includes an inner race 63 in which the spindle 6 is slidably tted, an outer race 64 carried by the support portion 49, and interposed anti-friction ball elements 66. This bearing prevents lateral displacement or whipping of the rear end of the spindle 6.

A flywheel or inertia member 66 is fixed on spindle 6 at a point between bearings 60 and 5| for reasons more particularly pointed out in a copending application of Joseph B. Armitage, Serial No. 750,440, tiled October 24, 1934, which is directed to this feature of the mechanism. A spindle brake generally denoted by numeral 61 may be used for quickly stopping the spindle. Brake 61 includes an arcuate member 68"best shown in Fig. 2, having a pivot 69 supported from the member 48. A brake band segment is ilxed on member 68 in a position to engage the periphery of ywheel 66. A hand operable button member 1| is connected to the member 61 by a member 12 and serves to permit the operator to engage the brake and quickly stop rotation of spindle 6 when desired, the brake being normally held disengaged by a spring 13.

The power for rotation of spindle 6 is derived from a self-contained primary motion motor which may be of any suitable form or type including a rotor member 14 which is fixed on spindle 6 at a point between the intermediate bearing 5| and the rear bearing 52. The motor stator element is xed with the portion 49 of the third support in manner to'be removed to expose the rotor when the portion 49 is removed. 'I'he position and relationship of the motor members relative to the grinding wheel and spindle bearings has been found to be of material benet in improving the action of the grinding wheel, particularly in maintaining a constant speed, and in reducing vibration or chatter.

What is claimed is:

1. In a cutter grinder, the combination of a base, a grinding wheel spindle and a cutter spindie-each rotatably supported from said base, and wheel spindle support means including a rst support slidably supported from said base for movement toward and from said cutter spindle, a second support slidably supported from said base for reciprocatory movement in a path transverse to the path of movement of said :rst support and a third support pivoted for movement about a horizontal axis transverse to the axis of said wheel spindle, said wheel spindle being journaled in said third support and vadjustable about said axis to various positions including a substantially horizontal position, and power means for driving said wheel spindle including a primary motion motor device providing a rotor ilxed with said wheel spindleand a stator iixed with said third support.

2. In a cutter grinder for sharpening face milling cutters, a base, a cutter supporting slide mounted .on'said base for horizontal linear adjustment, a grinder supporting slide mounted on said base for horizontal linear adjustment towards and from said cutter slide at right angles to the line of adjustment of said cutter slide, a cutter carrying bracket pivotally mounted on said cutter slide for angular adjustment in a horizontal-fplane, a cutter spindle support mounted for vertical linear adjustment on said cutter carrying bracket, a cutter carrying spindle journaled'horizontally in said cutter spindle support,

means for turning said spindle about its horizontally disposed axis to present theblades of a cutter carried thereby successively for sharpening, a grinder supporting bracket mounted on said grinder slide for lineal traverse at right angles to the direction of adjustment of said grinder slide,y 'a grinder spindle support pivotally mounted on said grinder supporting bracket for angular adjustment in a vertical plane, a grinding wheel spindle journaled for rotation in said grinder spindle support, a grinding wheel iixed to the end of said grinder spindle in cooperating relationship with said cutter supporting spindle, a iiywheel iixed on said grinder spindle, a self-contained driving motor directly connected to said grinder spindle, said grinder spindle and connected grinding wheel ywheel and driving motor together with said spindle support being movable as a unit in adjusting the position of said grinding wheel and in traversing said wheel in grinding relation with a cutter supported in said cutter supporting spindle, the supporting arrangement being such that there are four successive pairs of relatively movable bearing surfaces interposed between said grinder spindle and said base and likewise four successive pairs of relatively movable bearing surfaces interposed between said cutter spindle and said base.

3. In a cutter grinder forgrinding face milling cutters, the combination with a base and means on said base to support a cutter with its axis' in horizontal position and adjustable angularly and vertically; of a grinding unitmounted on said base including a grinding spindle and a grinding wheel a ywheel and a driving motor rotor mounted on said spindle, a support pivotally carrying said grinding unit for angular adjustment bodily in a vertical plane said support including a cooperatingv motor stator, a screw and nut mechanism for positioning said grinding unit angularly relative to said support, and clamping meansfor retaining said grinding unit in predetermined angular position.

4. In a cutter grinder, a base, means on said base for holding a cutter in position to be ground, a grinding unit including a grinding wheel and a driving motor carried by said base and operable to grind a cutter, a supporting element pivotally supporting said grinding unit on Said base for angular adjustment in a vertical plane said supporting element having arcuate slots at each side thereof, clamping bolts extending from each side of said grinding unit through said arcuate slots in manner to clamp said grinding unit to said y with a cutter supporting slide mounted o'n saidbase `for horizontal linear adjustment, a cutter carrying bracket pivotally mounted on said cutter supporting slide for angular adjustment in a hori- Zonta] plane,a cutter spindle-support mounted for vertical linear adjustment on said cutter carrying bracket, and a cutter `carrying spindle journaled horizontally in said cutter spindle support in position to present the blades of a cutter carried thereby for sharpening; of a grinder supporting slide mounted on said base for horizontal linear adjustment towards and from said cutter carrying spindle in direction at right angles to the line of adjustment of said cutter supporting slide, a grinder carrying bracket mounted .on

Y said grinder supporting slide for lineal traverse at right angles to the direction of adjustment of said grinder supporting slide, a grinder spindle support pivotally mounted on said grinder carrying bracket for angular adjustment in a vertical plane, and a grinding wheel spindle journaled for rotation in said grinder spindle support in position to present a grinding wheel f or cooperating witha cutter carried by said cutter carrying spindle; the supporting arrangement being such that universal adjustment is provided between a cutter being sharpened and a cooperating grinding wheel by mechanism having only four successive pairs of relatively movable bearing sury faces interposed betweenv said cutter carrying spindle and said base and likewise only four successive pairs ,of relatively movable bearing surfaces interposed between said grinding wheel spindle and said base.

FRANK W. CURTIS.