US3704846A - Apparatus for micropositioning an operational member and a workpiece platform - Google Patents

Abstract

Apparatus for micropositioning an operational member and a workpiece platform comprises either a fixed platform or a fixed operational member. In the fixed platform, four arms, each arm comprising a pair of substantially rigid coextensive resilient sections, extend between support posts affixed to the workpiece platform and a suspended operational member to angularly and translationally position the operational member relative to the workpiece platform by varying the extending length of each arm from the support posts by varying the spacing between each pair of resilient sections proximate their midpoints. In the apparatus for aligning the workpiece platform relative to the operational member, the platform has adjustable legs for angularly positioning the platform relative to the operational member and substantially rigid resilient translating legs fixed relative to the operational member, engaging the workpiece platform for translating the platform relative to the operational member by varying the length of each leg extending between its fixed point and the platform.

Description

United States Patent i451 DecQS, 1972 Clark [54] APPARATUS FOR MICROPOSITIONING AN OPERATIONAL MEMBER AND A WORKPIECE PLATFORM [72] Inventor: James A. Clark, Mendon, N.Y.

[73] Assignee: Bausch & Lomb Incorporated,

Rochester, N Y.

[221 Filed; nec.s,1969

[21] Appl. No.: 883,044

[52] U.S. Cl ..248/125, 248/274 [5l] Int. Cl ..F16m 13/00 [58] Field of Search.....l25/30.5;\5l/l66 TS; 248/44,'

Primary Examiner-William H. Schultz Attorney-Frank C. Parker and Bernard D. Bogdon [5 7 ABSTRACT Apparatus for micropositioning an operational member and a workpiece platform comprises either a fixed platform or a fixed operational member. In the fixed platform, four arms, each arm comprising a pair of substantially rigid coextensive resilient sections, extend between support posts affixed to the workpiece platform and a suspended operational member to angularly and translationally position the operational member relative to the workpiece platform by varying the extending length of each arm from the support posts by varying the spacing between each pair of resilient sections proximate their midpoints. ln the apparatus for aligning the workpiece platform relative to the operational member, the platform has adjustable legs for angularly positioning the platform relative to the operational member and substantially rigid resilient translating legs fixed relative to the operational member, engaging the workpiece platform for translating the platform relative to the operational member by varying the length of each leg extending between its fixed point and the platform.

11 Claims, 8 Drawing Figures P'ATENEDUE 5 |912 Y 3,704,846

SHEET 1 F 4 JAMES A. CLARK mvENTOR.

BERNARD D. BOGDON TTRNL' PATENEDE 5 i972 3,704,846

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JAMES r A. CLARK INVENTOIL BERNARD D. BOGDON PATENTED UEE 51972 3. 704 846 SHEU 3 nr 4T 74 6 9 e JAMES A. cum( l INVENTOR BERNARD D, 80600" rmx/7 PATENTEU nic 5 |972 SHEU lt F 4 JAMES A. cLARK INVENTOR.

BERNARD D.. BOGDON APPARATUS Fok MicRoPoslTIoNrNo AN OPERATIONAL MEMBER AND A WORKPIECE PLATFORM BACKGROUND OF THE INVENTION lationally micropositioning an operational member and l aworkpiece platform.

2. Description Of The Prior Art Micropositioning adjustment devices for accomplishin g accurate alignment are generally expensive to manufacture because of tightly held tolerances and frequently require `that extreme care be` used in their handling due to their` generally fragile construction and sensitivermechanisms. Frequently numerous sensors are necessary to monitor alignment during the operation of related machinery to insure that alignment is maintained. It is often the case where frequent operational shutdowns are necessary in order to check on the accuracy of the alignment and to make any necessary adjustments. Sensitive equipment monitoring devices are very costly and generally do not lend themselves to industrial environments involving the mass production of parts at ve ry great accuracies.

SUMMARY OF THE INVENTION This invention overcomes the `deficiencies of a significant number of prior art devices and provides a unique method of adjustment and apparatus for adjustment which is economical to manufacture andoperate, stable under a great'number of environmental conditions and reliable to the extend that monitoring devices are generally not necessary. The invention provides adjustable length support arms which are extensible from a fixed base or column to a member such as a workpiece platform of an operating mandrel. The apparatus provided for by this invention are ideally suited for use, for example, in the manufacture of optical lenses.

ln the case of the adjustable length support arms extending to carry an operating mandrel, a plurality of arms may be provided to angularly position the mandrel with respect to a fixed base and to translate the mandrel for very accurate alignment of, for example, an operating point on the mandrel and a workpiece supported by the base. Accuracy in the angular and translational alignment of the axis of the operating mandrel is only limited by the quality of the finish on the surfaces from which measurements are taken and the quality of the measuring equipment. The scope of the invention encompasses adjustable leveling devices for substantially transversely aligning a floating workpiece platform for operational orientation with a fixed mandrel. As a second step, adjustable length arms affixed to a base fixed relative to the operating mandrel are adjusted to translate the workpiece platform for orientation with the operational mandrel to thereby provide for very accurate angular and translational alignment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is a perspective view of an alignment apparatus according to the principles of the present invention for aligning an' operating mandrel;

FIG. 2 is an enlarged exploded fragmentary sectional perspective view of a typical mounting of an adjustable length arm of FIG. 1;

' FIG. 3 is a lateral view of the apparatus of FIG. l illustrating two positions of angular alignment of the operating mandrel; t

FIG. 4 is a lateral view of the apparatus of FIG. l illustrating two positions of translational alignment of the operating mandrel;

FIG. 5 is a perspective view of a machine employing an apparatus according to the principles of the present invention for aligning a workpiece platform relative to an operating mandrel; i

FIG. 6 is a sectional plan view ofthe machine of FIG. 5 along the plane of line 6--6 in FIG. 5;

FIG. 7 is a fragmentary lateral view of the workpiece platform and base of FIG. 6; and

FIG. 8 is a schematic illustration of two translational positions of the workpiece platform..

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. l illustrates an embodiment according .to the principles of the present invention comprising aworkbase 10 supporting transversely extendingbase pillars 12 and 14. To support anoperating mandrel 16, extending transversely frompillars 12 and 14 are fouradjustable length arms 18,20, 22 and 24. Each adjustable length arm comprises twocoextensive arm segments 26 and 28 having their respective ends rigidly affixed toend extensions 30 and 32 which are attached to eitherbase pillar 12 or 14, as the case may be, and theoperating mandrel 16, respectively. Thearm segments 26 and 28 are affixed to theend extensions 30 and 32 in any suitable manner, such as by means ofrivets 34. Theoperating mandrel 16, for example, carries a rotatable shaft 36 supporting a grindinghead 38 for performing a grinding operation on alens 40 mounted to apedestal 42 affixed to thebase 10.

As in obvious from the illustration in FIG. 1, the operating mandrel `16 can be translated and angularly positioned above thelens 40 simply by manipulation of anadjuster screw 44 which is threadably engaged with, for example, thearmsegment 26. Theadjuster screw 44 extends therethrough to bear-against the inside sur-v face of thearm 28 proximate the midpoint of thearm segments 26 and 28 to thereby vary, by manipulation, the spacing X between their inside surfaces to cause the extended length of each of theIarms 18, 20, 22 or 24 to vary from its fixed mounting at eitherpillar 12 or 14 to theoperating mandrel 16.

It will be appreciated that the spacing X of eacharm 18, 20, 22 and 24.need not be the same and in practice generally will not be even under conditions of transverse alignment at near equal distances from thepillars 12 and 14 since the elements comprising each arm need not be critically dimensioned and assembled and generally will not be for economic reasons, hence structural dimensions will vary. The variations promote no detrimental consequences, however, because of the unique adjustment features.

Although the apparatus disclosed is primarily for micropositioning, it will be appreciated that for freedom of movement and/or relatively long translations from a given point, thearms 18, 20, 22 and 2,4

should be free to rotate at their point of attachment to the pillars l2 and 14 and themandrel 16. Accordingly, as typically shown in FIG. 2, theengagement end 46 lof theend extension 30 is semi-circularly formed and definesaperture 48 for rotatably engaging thebase pillar 12. To this end ascrew 50 passes through anaperture 52 formed in thebase pillar 12 and theaperture 48 of theend extension 30 to threadably engage arectangular retainer nut 54. The engagement of theend extension 32 is similar.

j In practice, it is frequently desired to transversely dispose theoperating mandrel 16 to the workbase l0. FIG. 3 illustrates, for simplicity, only twoadjust ble length arms,.for example 18 and 20, in solid line onstruction extending unequal lengths between thebase pillar 12 and theoperating mandrel 16 to angularly dispose theoperating mandrel 16 other than transversely to the workbase l at Position A. The length ofadjustable arm 20 can either be shortened or lengthened merely by rotatingy theadjuster screw 44 in either desired direction. ln the illustrated case the length of adjustable arm- 20 isshortened to assume the broken line position. `By shortening the length ofadjustable arm 20 the bottom ofoperating mandrel 16 is thereby repositioned closer tobase pillar 12. In so doing theoperating mandrel 16 is transversely disposed to the workbase at Position B. It is understood that theadjuster screw 44 of eachadjustable arm 18, 20, 22 and 24 can beA manipulated to position the operating mandrel at any selected angle to theworkbase 10.

In a two part operation where both angular disposition and translation of theoperating mandrel 16 is required, the procedure followed as referred to in FIG. 3 is preferably accomplished first. Translational repositioning of theoperating mandrel 16 without affecting itsangular orientation may be performed by manipulation of the adjustingscrews 44 of both upper and lower extendingarms 18 and 20. This operation is best illustrated in FIG. 4 where themandrel 16 may be seen in -two positions indicated by solid line Position C andbroken line Position D, respectively. It will be appreciated that allarms 18, 20, 22 and 24 can be operated simultaneously, either manually or automatically, to translate the operating -mandrel 16 bidirectionally, i.e. along imaginary X and Y coordinates.

For rigidity of themandrel 16, four sets of adjustable length arms are preferred. However, it will be appreciated that certain adjustments can be accomplished with a fewer number of arms and with the arms affixed to thebase pillars 12 and 14 and themandrel 16 at other than oppositely disposed locations. Thearm segments 26 and 28 are preferably formed of resilient materials such as tempered spring steel. Tempered spring steel is rigid to support, for example, themandrel 16 but flexible to spread apart and change the extending length of each arm.

The embodiments illustrated in FIGS. l-4 are directed to apparatus for positioning an operational mandrel relative to a fixed base. It is frequently neces- Sary as dictated by the related machinery and environment to do the opposite and position the base relative t0 the mandrel. Accordingly, the embodiment illustrated in FIG. 5 is presented. Abase 56 supports amachine head 58 carrying arotatable shaft 60 having an operatingtool 62 for performing, for example, a boring or grinding operation upon aworkpiece 64, such as a lens or a lens cell. For operation upon optical elements, it is generally preferred that the axes of optical elements be aligned with the axes of the operating tools. To this end, optical elements are mounted upon awork platform 66 and positioned to asupport block 68 having a substantially circularly formed cut-out 70 comprising an arc of a circle for supporting a generally cylindrically shapedoptical element 64. Thework platform 66 is substantially square having chopped corners to form an unequal sided octagon and has located proximate each of its four chopped corners four height adjusting legs. 72 threadable engaged with thework platform 66 and extending therethrough to engage the top surface of thebase 56. y

In operation each threadedleg 72 is rotated to vary the amount of its extention between the underside of theplatform 66 and the top surface of the base 56 to vary the height of the surface of theplatform 66. To transversely align thework platform 66 with the operating axis of therotating shaft 60 coaxially supporting the operatingtool 62, theheight adjusting legs 72 are rotated to adjust the level of the top surface of thework platform 66 to achieve with the aid of any suitable measuring instrument perpendicular alignment between the periphery plane of therotating shaft 60 and the top surface of thework platform 66. A gage suitable for use in achieving the perpendicular alignment is, for example, a Brown and Sharpe Electronic Indicator, Model 992 with an electric indicating head. This invention provides apparatus for accurately aligning and stabilizing theworkpiece platform 66.

To translate theworkpiece platform 66 relative to the axis of therotating shaft 60 for alignment of a predetermined point on theworkpiece platform 66 with the axis, there is provided four translatinglegs 74, 76, 78 and 80. One each is disposed at each of the four corners of theworkpiece platform 66, as best seen in FIG. 6. Each of thefour translatinglegs 74, 76, 78 and y80 is supported above the top surface of the base 56 by ariser block 82 and is affixed to thebase 56 by means of a mountingscrew 84 passing through one end of each of the translating legs and itsriser block 82 to threadingly engage thebase 56. For engaging the other end of each of the translatinglegs 74, 76, 78 and 80, fourslots 86 are provided, one each in the lateral side at each of the corners of theplatform 66. Each translatingleg 74, 76, 78 and 80 is formed of resilient material and is variably extensible from its fixed mounting atscrew 84 by meansof anadjuster 88 extending through an aperture in each of the translating legs proximate their midpoint between their fixed mounting atscrew 84 and their engagement withslot 86. The head of theadjuster 88 bears against the top surface of the leg and its shaft passes through the leg aperture to threadingly engage thebase 56. Because each of the translatinglegs 74, 76, 78 and 80, as typically shown in FIG. 7 is bowed downward, it is not necessary during operation to use any additional means to maintain engagement between the ends of theheight adjusting legs 72 of theworkpiece platform 66 and the base 56 in order to hold the set leveled position of theplatform 66.

The translatinglegs 76 and 78 are primarily for urging thework platform 66 downward toward the base 56.l Fortranslatiomthe leg 74 engages theslot 86 and is affixed therein by means ofscrews 90 passing through the bifurcated corner of theplatform 66 and the end of the translatingleg 74, as best seen in FIG. 7. This en gagement insures a direct translational response when theadjuster 88 ofleg 74 is rotated. At the remaining corner of theworkpiece plateform 66, the translatingleg 80 engages theslot 86 and is affixed therein by means of asinglescrew 90 passing through the bifurcated section and theleg 80. The single screw attachment provides for pivoting of thevplatform 66 when it is translated. 1

lt will be appreciated that for translation theadjusters 88 are rotated to vary the extensible lengths of the translating legs from their fixed points relative to thebase 56. Theadjusters 88 are rotatable any amount and slight rotational movement can provide for very accurate alignment of a predetermined point on theworkpiece platform 66 with the axis of therotating shaft 60.

The schematic of' FIG. 8 illustrates translation of the.

workpiece platform 66 from a solid line Position E to a broken line Position F accomplished by rotation of theadjusters 88 of the translatinglegs 74 and 80.

Having thoroughly described my invention, as illustrated in the hereinbefore disclosed practical embodiments, I claim the following:

l. An apparatus for positioning in space a member relative to a base, comprising:

at least two adjustable length arms longitudinally extending from the member to means for supporting said adjustable length arms affixed to the base, each adjustable length arm having two coextensive sections and means for engaging said coextensive sections to said member and said means for supporting and further including means for adjustingv disposed between each pair of coextensive sections to vary the distance between said pair of coextensive sections and thereby vary the distance between the member and said means for supportmg.

2. The apparatus as defined in claim 1, wherein means for adjusting to vary the distance between the coextensive sections comprises an adjuster threadably engaged with one of the coextensive sections and disposed for bearing against the other coextensive section.

3. The apparatus as defined in claim l, wherein each coextensive section is resilient. j

4. The apparatus as defined in claim l, wherein one arm each is engaged to the member at opposite ends of the member.

5. The apparatus as defined in claim l, further including a third adjustable length arm engaging the member and extending substantially transversely therefrom to further` means for supporting said third adjustable length arm affixed to the base.

6. The apparatus, as defined in claim 5, wherein the third adjustable length arm comprises two coextensive sections longitudinally extending lfrom the member to said means for supporting and means for engaging said coextensive sections to said member and said means for supporting.

7. The apparatus, as defined in claim 6, further comprising means for adjusting disposed between each pair of coextensive sections to vary the distance therebetween and thereby vary the distance between the member and the means for supporting.

8. The apparatus, as defined inclaim 7, wherein the means for adjusting disposed between the coextensive sections comprises an adjuster threadably engaged with one of the sections and disposed for bearing against the other section.

9. An apparatus for positioning in space a member relative to a base, comprising; four arms longitudinally extending from the member to means forsupporting said arms affixed to the base, each arrn having a pair of coextensive sections including adjustable portions and means for engaging said coextensive sections to said member and said means for supporting and further including means for adjusting disposed between each pair of longitudinally extending sections to vary the distance between said pair of coextensive sections and thereby vary the distance between the member and said means for supporting.

10. The apparatus as defined in claim 9, wherein the coextensive sections are resilient.

11. The apparatus as defined inclaim 10, wherein the means to vary the distance between the sections comprises an adjuster threadably engaged with one of the sections and disposed for bearing against the other section.

Claims (11)

1. An apparatus for positioning in space a member relative to a base, comprising: at least two adjustable length arms longitudinally extending from the member to means for supporting said adjustable length arms affixed to the base, each adjustable length arm having two coextensive sections and means for engaging said coextensive sections to said member and said means for supporting and further including means for adjusting disposed between each pair of coextensive sections to vary the distance between said pair of coextensive sections and thereby vary the distance between the member and said means for supporting.

2. The apparatus as defined in claim 1, wherein means for adjusting to vary the distance between the coextensive sections comprises an adjuster threadably engaged with one of the coextensive sections and disposed for bearing against the other coextensive section.

3. The apparatus as defined in claim 1, wherein each coextensive section is resilient.

4. The apparatus as defined in claim 1, wherein one arm each is engaged to the member at opposite ends of the member.

5. The apparatus as defined in claim 1, further including a third adjustable length arm engaging the member and extending substantially transversely therefrom to further means for supporting said third adjustable length arm affixed to the base.

6. The apparatus, as defined in claim 5, wherein the third adjustable length arm comprises two coextensive sections longitudinally extending from the member to said means for supporting and means for engaging said coextensive sections to said member and said means for supporting.

7. The apparatus, as defined in claim 6, further comprising means for adjusting disposed between each pair of coextensive sections to vary the distance therebetween and thereby vary the distance between the member and the means for supporting.

8. The apparatus, as defined in claim 7, wherein the means for adjusting disposed between the coextensive sections comprises an adjuster threadably engaged with one of the sections and disposed for bearing against the other section.

9. An apparatus for positioning in space a member relative to a base, comprising; four arms longitudinally extending from the member to means for supporting said arms affixed to the base, each arm having a pair of coextensive sections including adjustable portions and means for engaging said coextensive sections to said member and said means for supporting and further including means for adjusting disposed between each pair of longitudinally extending sections to vary the distance between said pair of coextensive sections and thereby vary the distance between the member and said means for supporting.

10. The apparatus as defined in claim 9, wherein the coextensive sections are resilient.

11. The apparatus as defined in claim 10, wherein the means to vary the distance between the sections comprises an adjuster threadably engaged with one of the sections and disposed for bearing against the other section.

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