US2300481A - Machine tool - Google Patents

Description

M. H. ARMS MACHINE TOOLS Nov. 3, 1942.

3 Sheets-Sheet 1 Filed Oct. 30, 1939 M. H. ARMS MACHINE TOOLS Nov. 3, 1942.

3 Sheets-Shea 2 Filed Oct. 50, 1939 IIZZWZW? Nov. 3, 1942. M. H. ARMS 2,300,431

MACHINE TOOLS Filed Oct. 30, 1939. 3 Sheets-Sheet 3 Patented Nov. 3, 1942 mcnms 'roor.

Merton H. Arms, Springfield, Vt., assignor to Bryant chucking Grinder Company, Springfield, Vt., a corporation of Vermont Application October 30, 1939, Serial No. 301,935

16 Claims. (01. 51-3) This invention relates to machine tools and has for an object to provide such a machine capable of performing a plurality of different tooling operations. The invention is shown herein, by way of illustration and not of limitation, as embodied in a grinding machine in which different portions of the work may be ground to diiferent contours without requiring any adjustment of the tools relative to their immediate supports, there being one grinding wheel on a common carrier' for each of the different contours, and means whereby any selected wheel may be brought into operative position with relation to the work without interference from any other. The machine illustrated in the accompanying drawings is shown as tooled up for grinding portions' of different tapers on hub members.

Referring to the drawings,

Figure 1 is a front elevation of the machine.

Figures 2 and 3 are detail sections to a larger scale on section lines 22 and 3-3 of Figure 1, respectively.

Figure 4 is a detail section on line 4-4 of Fi ure 3 and showing one of the grinding wheels in operative position.

Figure 5 is a view somewhat similar to Figure 4, but showing the other wheel in operative position, a portion of the section being taken on line 55 of Figure 3.

Figure 6 is a detail section on line 36 of Figure 4, showing the wheel truing mechanism.

The machine as shown is of the general type illustrated in the Arms Patent No. 2,176,985 granted October 24, 1939, for Grinding machine. It comprises a bed I which supports a work support 2. This work support is provided with a rotary work spindle having a nose 3 and for the particular work shown this spindle nose has secured thereto a special work holder 4. As shown best in Figure 2, this work holder has an annular rim portion 5 which may be secured to the spindle nose 3 as by bolts 3. It is provided with an outwardly extending hub I having an axial opening to receive a mandrel 8. This mandrel 8 is provided with a flange 9 which may engage the outer end of the hub l and may have clamped thereto as by a'clamping disk In, a bushing II which surrounds the mandrel outwardly of the flange 9. This bushing II is externally splined and is adapted to be pressed into the central splined opening l2 of the hub M which is the particular piece of work intended ,to be operated upon in the embodiment herein shown. This hub has two internalsurface portions l5 and I3 which it is desired to grind at different angles to the axis of the hub, and either surface may be presented to grinding relation to its respective grinding wheel by selecting the particular. end of the hub to be positioned the more remote from the work spindle nose 3. After one of the faces l5 or l3 has been ground, the hub is removed from the work holder, turned end for end and placed back in position thereon so that the other of these surfaces may be ground.

The two grinding wheels 20 and 2|, the wheel 20 being employed to grind the face [6 and the wheel 2| to grind the face l5, are carried by their respective rotating shafts 22 and 23, both of which are joumaled in a tool arm 25 connected to rock about the axis of a supporting bar 26. This supporting bar is arranged for rocking and axial motion, being supported in suitable bearings 21 and 28 and being mounted similarly to the bar l3 shown in my patent hereinbefore mentioned. The arm 25 also carries at its upper end the driving motor 30. This motor is shown as pivoted at 3! between ears 32 extending from the arm 25 and supported by gravity with an abutment screw 33 threaded through an ear 34 of the motor casing engaging a suitable abutment 35 on the arm 25. A driving belt 38 passing around the motor pulley 31 also passes around a drive pulley 38 connected to the grinding wheel shaft 23, then up about an' idler pulley 33, down around a pulley 40 connected to the grinding wheel shaft 22, and back about an idler 4| to the pulley 31. Thus both of the grinding wheels are rotated by the same belt drive from the motor pulley 31.

The arm 25 is arranged to be supported in either one of two angular operative positions, in the forward of which the grinding wheel 20 is in substantial operative position, this being the full line position of Figure 3, and in the other of which the grinding wheel 2! is in substantially operative position, this being the dotted line position of Figure 3. The wheels are thus moved laterally of the work axis into and out of operative positions. In order that the same arm 25 may be employed inthis machine which is suitable for the machine of the patent hereinbefore mentioned, the shaft 23 and its grinding wheel may be mounted in a bracket which may be secured as by bolts to the forward face of the main portion of the arm 25.

For control of the feed of the grinding wheel 20 the same mechanism may be employed as shown in my patent hereinbefore mentioned, this comprising a downward and forward extension ll of the arm 23 which carries a suitable feed cam plate 59 which may traverse a roller 9| on the feed shaft 52, but in order that thefeed of the inding wheel 2| may also be provided for, this cam member 99 is supported by a bracket 98 t the lower portion of which is secured butment 84 which may be utilized when the gr ding wheel 2| is in operative position, as will iater appear. The axial position of the feed /shaft 62 may be determined by the feed wheel 95, the construction of these parts being identical with the similar parts shown in my pa'tent/ No. 2,176,985 to which reference has been made.

When the arm 25 is in its rearward operative position with the grinding wheel 2| operative, the cam abutment 54 is in .the dotted line position of Figure 3 and rests upon a roller 19 carried by a feed shaft II. This feed shaft is keyed for axial but non-rotating motion in a bushing I2 in a bracket frame member I3. The forward end of the shaft II is threaded as at 14 and passes through a threaded nut member I5 which is keyed within the hub of a bevel gear 15, so

that as this gear is rotated the feed shaft 1| is given an axial motion. This gear I6 meshes with a similar gear 11 on a horizontal shaft I8 joumaled in the base I of the machine and extended through to the forward face thereof where it has fixed thereto a gear I9. This gear of the grinding wheel 2|.

I9 is positioi :d beneath the feed shaft 82 and effective to swing the arm 25 to eilect feed of the grinding wheel 2| when this grinding wheel 2| is in operative relation to the work.

The retracted or right hand position of the arm 25 as viewed from the front of the machine is the same for both grinding wheels, and the rocking motion of the arm 25 to change from the angular position when one wheel is operating to that for the other wheel, is arranged to take place when both wheels are retracted. A freely rotatable abutment roller 99 mounted for limited vertical motion, is carried by the bracket member 45, this roller being arranged to contact with either of two limiting stop track plates 9| and 92. When the roller 99 is in engagement with the track plate 92, it is held in its rear operative position where the grinding wheel 2| is operative, while when it is in engagement with the trackway 9|, the arm 25 is in its forward operative position with the wheel 29 in operative position. This roller 99 may be lifted from its normal position, and for this purpose it is carried by a slide 93 mounted for vertical motion and carried by a rod 94 retractible in the bracket45. To the upper end of this rod 94 is pivoted a lever 95 which is fulcrumed on a post 98 projecting upwardly from the top of the bracket 45. The slide 93 and the rod 94 are normally held downwardly, as by the spring 91, having its opposite end seated in sockets 98 and 99 of the bracket and the slide 99, respectively.

It will be noted that the arm 25 which carries the grinding wheels is biased by gravity toward a position with the roller 99 engaging the operative position. when the arm 25 is in its backward positionwith the roller 99 engaging the limit stop 92, release of the roller 99 by depressing the .handle 95 will not free the arm 25 for its forward swinging motion unless the arm 25 is adjacent to its outer limit of motion, since at other times the cam 54 is in engagement with or will contactthe roll I9.

Referring to Figure 5, it will be.noted that the cam abutment 54 has a pair of high points I99 and MI. From these high points the cam edge falls away in one direction to the points I92 and I98 corresponding to the inclination of the edge On the other side of the high point |9I the cam edge falls away rapidly. The cam edge from the point IN to the point I93 is that which engages the roll 19 when the grinding wheel 29 is retracted from the work and is in position to be dressed and after the point I9I passes out of contact with the roller 19, the arm 25 is held in its rearward position only by the engagement of the roller 99 on the limit stop 92. In this position of the parts, depression of the handle 95 lifting the roller 99, frees the arm 25 for forward swinging until either the roller 99 contacts with the limit stop 9| or the cam 99 engages the roller 6| of the feed screw 62. The roller 19 engages the other portion of the cam 84 between the high point I99 and the low point I92 during the active traverse of the grinding wheel on the work, this slope coupled with the inclination of the wheel edge, causing the wheel to grind the desired taper on the face I9 of the work. When the arm 25 is in its forward operative position the limit for which is determined by the engagement of the roller 99 on the limit ,stop 9|, the cam abutment 69 is positioned in operative relation to the feed cam roller 5|. This cam 89 has a high point I95 and a low point I96, the slope between which engages the roller 9| when the wheel is out of the work and guides it for the truing operation. The grinding operation is controlled by the sloping por,

5 tion of the cam from the high point I91 to the low point I99. From the point I95 to the outer end of the cam at I99 there is a flat portion which bears on the cam roller 9|, except when the cam roller 5| is in a sufliciently retracted position so that theroller 99 may reach the limit stop 9I. There is also a flat portion from the point I98 to the opposite extremity 9 which forms a support for the wheel should it be carried in further than its normal grinding path. As shown, each of the cam elements 69 and. is in two Parts, one of which carries the truing contour portion, and the other of which carrles the grinding contour portion, but functionally they might be in a single piece.

As shown in Figures 4 and 6, the truing device may be hand controlled instead of being poweractuated as in my Patent No. 2,167,985 hereinbefore mentioned. Preferably each of the faces I5 and I9 of the work are operated upon successively by a roughing and a truing wheel, which are interchangeably secured to their respective shafts 23 and 22. Where this is done the truing tool II5 may take four different positions corresponding to the two grinding wheels for operating on each of the work surfaces I5 and I5. As shown this truing device is carried by a lever II8 mounted for rocking motion on a ball bearing II! on a fulcrum shaft II4. This arm IIIi limit stop 9| and with the grinding wheel 29 in is provided with n ac uating handle II5 havhig ment I23 engageable with any selected of the screws I22 which may be brought into position therebeneath by turning the turret I20. Due to the rocking motion of the arm 25, the line of contact between the wheel and the work changes with changes in the diameter of the grinding wheel and variations in deflection of the machine parts. The height of the contact between the dressing tool and the wheel to produce the proper wheel contour is thus critical, even though it is possible to correct the wheel contour by proper correction in the contour of that portion of the abutment cam traversed during the truing action. Individual vertical adjustment of the truing device for each of the four wheels employed is thus of considerable importance. The arm H6 may be thrown backwardly into the inoperative dotted line position by the opera tor, and is moved forwardly whenever it is desired to true the grinding wheel.

This truing mechanism and mounting per se is not claimed herein as it forms subject matter of a divisional application Serial No. 431,371 filed February 18, 1942, for Wheel truing mechamsm.

In operation of the machine, the sleeve II is assembled with the work piece and then the two are laced in position on the spindle 8, as shown in Figure 2, with either selected end outwardly positioned. The arm 25 having been adjusted to the proper angular position to correspond with the particular face I-or l6 which is presented in grinding position and with a roughing wheel thereon, is then manipulated to engage and grind from the spirit or scope of this invention as defined by the appended claims.

I claim:

1. In combination, a .machine bed, a work holder carried by said bed, a tool carrier carried by said bedand movable parallel to and laterally of the axis of said work holder, a plurality of tools carried by said carrier spaced laterally of said axis, means for supporting said carrier in any selected one of a plurality of positions in each of which one of said tools is in cooperative lateral relation to work carried by said. work holder, means for reciprocating said carrierparallel to said axis, and mechanism carried by said bed and individual to each of said tools to produce a relative lateral feed of its tool with respect to work carried by said work holder.

2. In combination, a machine bed, a work holder carried by said bed, a tool carrier carried by said bed and movable parallel to and laterally of the axis of said work holder, a plurality of tools carried by said carrier spaced laterally of said axis, means for supporting said carrier in any selected one of a plurality of positions in each of which one of said tools is in cooperative lateral relation to work carried by said work holder, means for reciprocating said carrier parallel to said axis, and mechanism carried by said bed and individual to each of said tools to produce a relative lateral feed of its tool with respectto work carried by said work holder and defining a path of motion of said tool with respect to the work during the reciprocation of said carrier to produce a desired contour on the work.

3. In combination, a machine bed, a work holder carried by said bed, a tool carrier on said bed, a plurality of tools on said tool carrier, means supporting said holder and carrier for relative motion to present any selected tool into operative relation to work on said work holder, said holder and carrier being relatively biased to assume relative positions with one of said tools cation of the grinding wheel being controlled,

for example, by the hydraulic mechanism illustrated in my Patent No. 2,176,985. After the rough grinding operation is complete, the wheel is retracted and the machine stopped and the finish grinding wheel substituted for the rough grinding wheel. The grinding operation then proceeds as before until the work is finish ground, after which the arm 25 is retracted, the work removed from the spindle 8, reversed end for end, and replaced thereon, whereupon the other grinding shaft with the rough grinding wheel thereon is brought into operative relation and the wheel traversed to effect rough grinding of this second tapered faceto its particular angle. After the rough grinding has been accomplished, the arm 25 is retracted, a finish grinding wheel substituted for the rough grinding wheel, and the machine then again actuated to finish grind that particular face of the work. At suitable times the operator may retract the grinding wheel then in operation and effect a truing pass by extending the traverse away from the work with the truing tool brought down into operative relation into the position suitable for that particular grinding wheel as determined by the setting of the abutment turret I20.

From the foregoing description of an embodiment of this invention, it should be evident to those skilled in the modifications that various changes and in substantially operative relation to the work, means for releasably holding said holder and carrier in relation to present another of said tools in operative relation to work on said holder, and means for each of said selected relative positions for effecting a traversing tooling operation axially of the work by the tool then in operative relation on work held by said holder.

4. In combination, a machine bed, a work holder carried by said bed, a tool carrier on said bed, a plurality of tools on said tool carrier, means supporting said holder and carrier for relative motion to present any selected tool into operacarrier in relation to present another of said tools in operative relation to work on said holder, means for each of said selectedrelative positions for effecting a tooling operation by the tool then in operative relation on work held by said holder,

and means carried by said bed for each tool for effecting a feed of the tool inoperative position relative to the work.

5. In combination, a machine bed, a work holder carried by said bed, a multiple tool carrier mounted on said bed for motion transverse to the axis of said work holder and biased to a position wherein one of the tool of said carried is in substantially operative transverse relation to work held by said work holder, means producing a relative traverse between said holder and carrier, means carried by said bed and individual to each tool for moving said tool carrier in opposition to biasing direction to effect a feed motion of its tool relative to the work, certain of said feed mechanisms being inoperative when said work holder and tool carrier are in relative retracted traverse positions, and releasable means for holding said tool carrier against motion in biased direction from said selected tool-operative transverse position, whereby on release of said releasable means when said carrier is in said relative retracted positions said carrier may be moved from one to another of its selective transverse positions.

6. In combination, a machine bed, a work holder carried by said bed, a tool carrier carried by said bed and movable parallel to and laterally of the axis of said work holder, a plurality of tools supported by said carrier spaced laterally with respect to said axis, means for holding said tool carrier to present any selected one of said tools into cooperative relation to work carried by said work holder, means for holding said tool carrier against change from the position of said carrier in which one of said tools is in operative relation to the work to the position in which another of said tools is in operative relation to the work, and means carried by said bed and individual to each tool for producing relative feed between such tool and the work.

7. The combination with. a rotary work holder and an arm pivoted substantially parallel to the axis of rotation of said holder and a machine bed supporting said holder and arm, of a plurality of tools carried by said arm for selective positioning opposite to work carried by said work holder, said arm and tools being biased by gravity to bring one of said tools into substantially operative alinement with work on said holder, means for relatively moving said holder and arm operative position to permit such swinging of said arm to the other of its selective positions.

9. The combination with a rotary work holder and an arm pivoted substantially parallel to the axis of rotation of said holder and movable axially thereof, of a pair of grinding wheel shafts journaled in said arm, a grinding wheel on each shaft for selective cooperation with said work holder by the swinging of said arm about its pivot to bring the selected wheel into operative alinement with the work and then by axial motion of said arm to traverse the work, a feed mechanism for each wheel, a pair of cam abutments carried by said arm each for engagement with its respective feed mechanism for controlling the path of said wheel as said arm is moved axially, a wheel truing device across which either of said wheels may be passed by axial motion of said arm, said wheel truing device being mounted for movement to an inoperative position, selective means defining an operative position for said device corresponding to each wheel, said cam abutments each having a dressing cam face controlling the path of the truing pass of the corresponding wheel to cause said wheels to 3 be dressed to the proper contours to produce the to effect traverse of the work and that tool in operative alinement with the work at any time, a feed mechanism for each tool mounted on said bed for engagement with said arm when its tool is in operative alinement with the work, said arm being mounted for motion beyond the range of certain of said feed mechanisms to permitsaid arm to be turned to change from one to another of said selective positions and into the control of that feed mechanism corresponding to the position selected.

8. The combination with a rotary work holder and an arm pivoted substantially parallel to the axis of rotation of said holder and movable axially thereof, of a pair of grinding wheel shafts joumaled in said arm, a grinding wheel on each shaft for selective cooperation with said work holder by the swinging of said arm about its pivot to bring the selected wheel into operative alinement with the work and then by axial motion of said arm to traverse the work, a feed mechanism for each wheel, a pair of cam abutments carried by said arm each for engagement with its respective feed mechanism for controlling the path of said wheel as said than is moved axially, one of said cams terminating short of the axial motion of said arm to permit said arm to be swung to the other selective position when beyond said cam, cooperative, limiting abutments, one on said arm, for normally preventing such swinging motion of said arm, and means for removing one of said cooperative abutments from desired ground contours of the work effected by the two wheels.

10. The combination with a plurality of grinding wheels, and-means for selectively presenting any one of said grinding wheels in operative relation to work, of a single truing device for all of said wheels, means supporting said device for motion between an inoperative and operative positions, means for selectively defining said operative positions individually in accordance with the requirements of the respective wheels, and means for effecting traverse between the presented wheel and the work and between the presented wheel and said dressing tool along contour paths individual to the respective wheels and independent of the contour path for any other wheel.

11. The combination with a plurality of grinding wheels, and means for selectively presenting any one of said grinding wheels in operative relation to work, of a single truing device for all of said wheels, means supporting said device for motion between an inoperative and operative positions, means .for selectively defining said operative positions individually in accordance with the requirements of the respective wheels, and means for effecting traverse between the presented wheel and the work and between the presented wheel and said dressing tool along contour paths individual to the respective wheels and independent of the contour path for any other wheel and with the contour paths for dressing independent of the contour paths for grinding.

12. In combination, a wheel carrier, a plurality of grinding wheels supported by said carrier, means for supporting said carrier for adjustment to bring any selected one of said wheels into operative position, a single truing device for all of said wheels, means for supporting said device for motion between an inoperative and operative positions, means for selectively defining said operative positions individually corresponding to the adjustments of said carrier, and means for effecting traverse between the presented wheel and the work and between the presented wheel and said dressing tool along contour paths individual to the respective wheels and independent of the contour path for any other wheel.

13. In combination, a wheel carrier, a plurality of grinding wheels supported by said carrier, means for supporting said carrier for adjustment to bring any selected one of said wheels into operative position, a single truing device for all of said wheels, means'for supporting said device for motion between an inoperative and operative positions, means for selectively defining said operative positions individually corresponding to the adjustments of said carrier, and means for effecting traverse between the presented wheel and the work and between the presented wheel and said dressing tool alongcontour paths individual to the respective wheels and independent of the contour path for any other wheel and with the contour paths for dressing independent of the contour paths for grinding.

14. The combination with a plurality of grinding wheels and means for relatively presenting any one of said grinding wheels in operative relation to work, of a single truing device for all of said wheels, means supporting said device for motion between an inoperative and operative positions independently determined for each wheel, means for efiecting traverse of the selected wheel relative to said work and to said truing device including a template and a follower for traversing said template, there being a template for each of said 'wheels, each of said templates having a contour controlling the transverse rela- 15. In combination, a wheel carrier, a work holder, a plurality of grinding wheels supported by said carrier, means supporting said carrier for adjustment to bring any selected one ofsaid wheels into operative position with relation to a work piece on said holder, a single truing device for all of said wheels, means supporting said tion of its wheel during the traverse of the work by said wheel and a contour defining the trued shape of said wheel when said wheel traverses said truing device.

device for motion between an inoperative position and any selected operative position independent for each of said wheels, means for moving said wheel carrier to cause traverse and feed of the selected wheel with relation to the work piece and to the truing device, said moving means including a template independently contoured for each wheel and having one portion contoured to control the relation between its respective wheel and the work and another portion contoured to control the shape of the wheel as trued by said truing device.

16. In combination, a bed, a work holder carried by said bed, a wheel carrier, a plurality of grinding wheels carried by said wheel carrier, means supporting said wheel carrier from said bed for adjustment to bring any selected one of said wheels into operative relation to work on said work holder, a single truing device for all of said wheels, means supporting said device for motion between inoperative and operative positions, and means for selectively defining said operative positions individually corresponding to the several wheels.

MERTON H. ARMS.

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