US1257046A - Lapping-machine. - Google Patents

Lapping-machine. Download PDF

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US1257046A
US1257046A US21007218A US21007218A US1257046A US 1257046 A US1257046 A US 1257046A US 21007218 A US21007218 A US 21007218A US 21007218 A US21007218 A US 21007218A US 1257046 A US1257046 A US 1257046A
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lap
plates
plate
lapping
machine
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US21007218A
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Edward A Suverkrop
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B37/00Lapping machines or devices; Accessories
    • B24B37/04Lapping machines or devices; Accessories designed for working plane surfaces
    • B24B37/07Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool
    • B24B37/08Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for double side lapping

Definitions

  • This invention relates to the making of metal pieces which ness, and as to the parallelism1 iatness and smoothness of their opposite surfaces.
  • the object of the present invention is to provide mechanism which will lap hard 'metal in such manner that gage blocks as satisfactory as standard hand made gages can be produced, having extremely accurate dimensions and parallel, fiat and smooth opposite surfaces, in a short time with a minimum amount of labor and by relatively unskilled persons,
  • apparatus for attaining this end has two fiat lapping plates either made of or charged with abrasive material, and one or both. being. movable toward and from the other?, with means for setting these Alapping plates absolutely parallel 'and'maintaining them parallel, means for setting the lapping plates a positive distance apart and insuring their stopping when a proaching at an exact distance from each ot late for holding' the pieces to be lapped etween the lapping plates, and mechanism for imparting relative compound movement or movement in ,more than one direction between the work plate and the lap ing plates, and desirably at different' spee s, in order that every .portion of the sur-faces to be lapped shall be subjected to.
  • Fig. 4 shows a ycentral vertical section of the machine.
  • Fig. 5 shows a section of portions of two annular plates that may be used on the machine for and bringing the pieces to be lapped 4to approximate size.
  • the machine illustrated has a cylindrical casing 1 mounted on a stationary bed 2. Resting on a flange 3 near the upper end o f the casing is the annular ,lower lap plate 4.
  • the upper surface 5 of this lap plate may be formed of or charged in the usual way with abrasive material'.
  • hubs 6 At three points about the sides of the lower lap plate are hubs 6 with vertical bores. In these bores and extending upwardly from the hubs are guide posts 7 that may besecured with' their upper ends at any desired height by clamps 8.
  • the annular upper lap plate 9 which has sleeves to'sward and from the upperA ends of the guide posts are micrometer stop screws 13. Openings x 14 are 'made transversely through the sleeves so that the upper ends of the guide posts and the lower ends of the stop screws may'be observed and standard gage blocks- 15 placed between these parts.
  • a ro'tatable conical 'sleeve 16 is fitted in the tapering bore of thecasing.
  • This sleeve may be rotated in the v'casi-ng -bv any suitable f means as, for instance, it may have on its lower. end a' spiral engaged by 'a spiral pinion or' worm 18 'on a s 'aft 19. that may e drivenl by any 'con- 'ven-ient means so 'as sleeve slowly.
  • Extending throiigh'the rotatable sleeve 'and having its axis eccentric with relation to the axis vof'the sleeve is a shaft 20.l Anti-friction bearings 21 may be provided Afor su porting this shaft in the sleeve.
  • On the -ower end of the eccentric shaft vis a pulley 22 which may be driven by- 't'o rotate -the any "convenient means so as shaft' at the ,shaft rapidly.
  • gear or worm wheel 17' sleeve is a collar 23 and to rotate the conical .i
  • the work plate is, while rapidly rotated, slowly res .volved so that the pieces being lapped, while carried rapidly around between the lapping i "surfaces of the two lap plates,'are slowly 'carried in and outbetween the innerand outeredges of the lapping surfaces of the lap plates.
  • all the sur faces lapped are subjected to every portion of the lappin 'continued unti as the pieces are worn 'awayI the-lower ends of the micrometer screws reach and impinge upon the upper surfaces 01E-the standard ga es on the ide posts, then, of course, as ⁇ t e upper pate-'can de sendno farther the lapping of the pieces ceases.
  • the lapping sur 'aces of which are made of or charged with hard granular abrasive -materiaL-inay be removed and themachine provided with laping or grinding plates, suchwas shown'in Fig. 5, for preliminary grinding.
  • the lower and upper plates 28 and 29 may be grooved ⁇ and rings of India oil stone 30 and annees ai or other estable With the machine' ..001 of an inch of surfaces
  • the lapping is l 'etween the lap plates, and means for ini- .iis
  • grinding material may grooves .of the rings. set-'lip in this way the pieces to be formed into gage blocks and which have previously been hardened and 'fo ground on a surface grinder to, say, within finished size, maybe lapped so as to bring vthe pieces toapprgxi mately .0001 or .0002 Vof'an inch D" be cemented in the over' the finished size.v The pieces having been refja **d to this size are then lapped in the same machine provided 'with the la plates lirst described or in another machine pro-l vided with such lap plates' and reduced to finished size. In apparatus embodying this 8U invention pieces have been lapped, very rapidly 'to less than .00005 of an iiich of absolute dimension. and parallelism.
  • T e invention claimed is; v.
  • a lapping machine having parallel lap plates. with abrasive opposing surfaces g5 mounted so the, distance betweenl them can bedecreascd', guides for insuring theparal.- lelisin. of the lap ing surfacesv at' all'ftiin adjustable stops 0r limiting the closingto--- getiier of the lappin surfaces, a worii ice plate between the lap p ates,iandmeans for .imparting rela:tive ⁇ . movement between the lap plates and the work plate in more than one direction, whereby the opposite surfaces of the pieces carried b the work plate will ies be subjected to the' a rasive action of the .lapping surfaces of the lapA plates$ 2.
  • a lapping machine having parallel la. plates with flat abrasive opposingsurfaccs mounted so the distance between thenicanv be decreased, guides Vfor insuring the paral- 12:.- lelism ofthe lap in surfaces at all times, adjustable sto s ibi? limiting the closing together of the lgapping surfaces, a work plate between the la plates, andlneans for mov-- ing the work p ate between .the lap plates in luft more than one direction, whereby the opposite surfaces of the pieces carriedby the work plate will be subjected to the abrasive action of the lapping surfaces of the lap plates.
  • a lapping machine having parallel lap plates with fiat abrasive opposing surfaces, one of which is movable toward the other, guides for insuring the parallelism of the lapping surfaces at all times, adjustable stops for limiting the closing of said movable lap plate toward the other lap plate, a work plate between the lap plates, and means for moving the work plate between the la plates in morethanone direction, where y the opposite surfaces of 'the pieces carried by the work plate will be subjected to the abrasive action of the lapping surfaces of the lap plates,
  • a lapping machine having parallel lap ,plates with flat abrasive opposing surfaces mounted so the distance between them canv be decreased, uides for insuring the parallelism of the lappin surfaces at all times, adjustable sto s for l(limiting the closing together of the apping surfaces, a work plate between the lap plates, and means for imparting relative rotary movement between the vlap plates and the work plate in more than one direction, whereby the opposite surfaces of the pieces carried by the work plate will be subjected to Jthe abrasive actioigg of the lapping surfaces of the lap plates.
  • a lapping machine having parallel lap plates with fiat abrasive opposing surfaces mounted s oj-the distance between them can be decreased, uides for insuring the parallelism of vthe la-pping surfaces at all times, adjustable sto s for limiting the closing together of the apping surfaces, a work plate between the lapl lates, and meansfor rotatin the work 'p ate about ,its-,axis and revo ving the axis of -the wokplate between thelappllates, whereby vthe' opposite surfaces of t e pieces carried by -tlie'work plate willbe subjected-to the abrasive action of tliela. ing surfaces of the'ilap plates. lapping machine -having parallel lap plates vwith fiat 'abrasive opposing surfaces,
  • a lapping machine having parallel lap plates with flat abrasive opposin surfaces, one lap plate being stationary' an the other movab e toward the stationary plate, guides for the'movable plate mounted on the stationary plate for insuring the parallelism ofthe lapping surfaces at all times, adjustable stops mounted on the movable plate for limiting the closing of said movable plate toward'the stationary plate, a work plate between the lap plates, and means for rotatsurfaces, a work plate between the lap plates, and means for rotating the work plate about its axis and revolving the axis of Ithe work plate between the la plates, whereby the opposite surfaces of tlie ieces carried by the work plate will be subjected to the abrasive action of the lapping sur faces of the lap plates.
  • a lapping machine' having parallel removable. annular lap plates with/flat abrasive opposing surfaces mounted so the distance between them can be decreased,
  • lappin suifacesat all ltimes, adjustable stops or limiting the closing vtogether of the lapping surfaces, a work plate between the lap plates, and means for rapidly rotating the lwork plate aboutits axis and slowly revolving the axis of the work plate between the lap plates, whereby the opposite surfaces of the pieces carried by the work plate will be subjectedto the abrasive action the lapping surfaces of the la lates.

Description

E. A. SUVEHKEOP.
LAPPING MACHJNE.
APPLICATION FILED IAB. 23. |917. RENVIED IAM. 2.1918.
mumm v gage blocks and the like are required to be very accurate as to thick-` lat ,neutralize any heatin UNITED ,STATES PATENT OFFICE EDwAnn a. auv'nnimor, or 'SEA curia', maw Yonx.
nurme'lmacmim Application tiled Hatch 28, 1917, Serial No. wte.y
To all 'whom z't ma concern:
e it known t at I, EDWARD A. SUvnR- Kllor, a 'citizen of the United States, resid ing at. Sea. Oli-ii', Long Island, in the State ew' York, have invented a new and useful Improvement in Lapping-Machines, of which the following is a specification.
This invention relates to the making of metal pieces which ness, and as to the parallelism1 iatness and smoothness of their opposite surfaces. a
The object of the present invention is to provide mechanism which will lap hard 'metal in such manner that gage blocks as satisfactory as standard hand made gages can be produced, having extremely accurate dimensions and parallel, fiat and smooth opposite surfaces, in a short time with a minimum amount of labor and by relatively unskilled persons,
Broadly, apparatus for attaining this end has two fiat lapping plates either made of or charged with abrasive material, and one or both. being. movable toward and from the other?, with means for setting these Alapping plates absolutely parallel 'and'maintaining them parallel, means for setting the lapping plates a positive distance apart and insuring their stopping when a proaching at an exact distance from each ot late for holding' the pieces to be lapped etween the lapping plates, and mechanism for imparting relative compound movement or movement in ,more than one direction between the work plate and the lap ing plates, and desirably at different' spee s, in order that every .portion of the sur-faces to be lapped shall be subjected to. the action of the entire lap ing surfaces, and thus eliminate material 'y the wear ofthe laps. and and peening effect and insureuniform a rasion of the pieces lapped 'so that the product will be extremely 4accurate in dimensions, parallelism iiatness and smoothness and yet be rela tivel' Of the accompanying drawings shows a planjof a machine that embodies the invention, in whichthe lap plates Vare annu-v lar and stationary 'while the work holding "plate is lcircular and is rotated rapidly on an -axis that is revolved slowly so" that'the la ped ieces willtravel-'in an hypocycloida stili)- between the"lap'ping surfaces of the 'lli-p plates. 1 Fi 2-shows-a's1de elevation 'of -this machine. iz.- 8 shows a planwith Specification of Letters Patent.
er, a work Patented Feb. 19, 1918. Renewed January 2, 1818. Serial No. 210,072.
the upper lap plate removed. Fig. 4 shows a ycentral vertical section of the machine. Fig. 5 shows a section of portions of two annular plates that may be used on the machine for and bringing the pieces to be lapped 4to approximate size.
The machine illustrated has a cylindrical casing 1 mounted on a stationary bed 2. Resting on a flange 3 near the upper end o f the casing is the annular ,lower lap plate 4. The upper surface 5 of this lap plate may be formed of or charged in the usual way with abrasive material'. At three points about the sides of the lower lap plate are hubs 6 with vertical bores. In these bores and extending upwardly from the hubs are guide posts 7 that may besecured with' their upper ends at any desired height by clamps 8.
preliminary lapping and grinding The annular upper lap plate 9, which has sleeves to'sward and from the upperA ends of the guide posts are micrometer stop screws 13. Openings x 14 are 'made transversely through the sleeves so that the upper ends of the guide posts and the lower ends of the stop screws may'be observed and standard gage blocks- 15 placed between these parts.
In the tapering bore of thecasing a ro'tatable conical 'sleeve 16 is fitted. This sleeve may be rotated in the v'casi-ng -bv any suitable f means as, for instance, it may have on its lower. end a' spiral engaged by 'a spiral pinion or' worm 18 'on a s 'aft 19. that may e drivenl by any 'con- 'ven-ient means so 'as sleeve slowly. Extending throiigh'the rotatable sleeve 'and having its axis eccentric with relation to the axis vof'the sleeve is a shaft 20.l Anti-friction bearings 21 may be provided Afor su porting this shaft in the sleeve. On the -ower end of the eccentric shaft vis a pulley 22 which may be driven by- 't'o rotate -the any "convenient means so as shaft' at the ,shaft rapidly. Fixed Aon the upper end'of the 'fastened to this by'an screwsfi, is thewor Washers`26 are located on suitable means, as
gear or worm wheel 17' sleeve is a collar 23 and to rotate the conical .i
holding plate 251 the shaft between the collar and work plate so as to locate the Work. plate in proper position for efficient the lapping surface ofthe lower lap plate. f
With the lap plates together in this manner the stop screwsare turned'down until they' impinge on the upper' ends of the guide posts. The upper lap plate is 4then lifted 0H and the work plate secured in position on the shaft with the pieces to be lappedin the openings provided therefor, aftefwhich the upper -lap plate is again put in place on the guide posts and standard gage blocks' of f the thickness to which the blocks carried by the work plate are to be reduced by lepp'in'g are placed between the upper ends o the guideposts and the lower'ends of .the stop screws.. As the blocks to be lapped are, of
course, over sizeV the lower ends of theI stop screws-are a slight distance above the tops of the standardy gage Ablocks on the upper ends'of the guide posts. After the machine has been set inl operation the work 1plate is. rotated rapidly'by means ofthe pu eyand shaft and at the same time the' sleeve4 is rotated slowly by means of the spiral gears.- This carries the axis of therapi ly rotatin' shaft slowly around in a circle, the radius o which is equal to the distance betweenithe axis of the sleeve and the axis ofthe solid yso shaft. As a result of these motions the work plate is, while rapidly rotated, slowly res .volved so that the pieces being lapped, while carried rapidly around between the lapping i "surfaces of the two lap plates,'are slowly 'carried in and outbetween the innerand outeredges of the lapping surfaces of the lap plates. By means o f this all the sur faces lapped are subjected to every portion of the lappin 'continued unti as the pieces are worn 'awayI the-lower ends of the micrometer screws reach and impinge upon the upper surfaces 01E-the standard ga es on the ide posts, then, of course, as` t e upper pate-'can de sendno farther the lapping of the pieces ceases.
With this type of machine both the u per and lower lap plates, the lapping sur 'aces of which are made of or charged with hard granular abrasive -materiaL-inay be removed and themachine provided with laping or grinding plates, suchwas shown'in Fig. 5, for preliminary grinding. yIn this case the lower and upper plates 28 and 29 may be grooved `and rings of India oil stone 30 and annees ai or other estable With the machine' ..001 of an inch of surfaces The lapping is l 'etween the lap plates, and means for ini- .iis
grinding material may grooves .of the rings. set-'lip in this way the pieces to be formed into gage blocks and which have previously been hardened and 'fo ground on a surface grinder to, say, within finished size, maybe lapped so as to bring vthe pieces toapprgxi mately .0001 or .0002 Vof'an inch D" be cemented in the over' the finished size.v The pieces having been refja duced to this size are then lapped in the same machine provided 'with the la plates lirst described or in another machine pro-l vided with such lap plates' and reduced to finished size. In apparatus embodying this 8U invention pieces have been lapped, very rapidly 'to less than .00005 of an iiich of absolute dimension. and parallelism.
With these machines a number of blocks may at `the same time `be by relatively un` sa skilled labor .quicklyrediced .to the dimenf sions of standard gage blocli's' without danger of the blocks curling because both sides are heated and peened equally' and simultaneously, and this insures that their so opposite surfaces be Smooth, flat planes .that are arallel.
T e invention claimed is; v.
1 A lapping machine having parallel lap plates. with abrasive opposing surfaces g5 mounted so the, distance betweenl them can bedecreascd', guides for insuring theparal.- lelisin. of the lap ing surfacesv at' all'ftiin adjustable stops 0r limiting the closingto--- getiier of the lappin surfaces, a worii ice plate between the lap p ates,iandmeans for .imparting rela:tive`. movement between the lap plates and the work plate in more than one direction, whereby the opposite surfaces of the pieces carried b the work plate will ies be subjected to the' a rasive action of the .lapping surfaces of the lapA plates$ 2. A. lapping machine having parallel lap plates with fiat abrasive opposing surfaces mounted so the distance between the-iii can ige,- be decreased, guides for insuring theY parels lelisni ofthe lap ing surfaces at all times, adjustable sto s or limiting. the closing tom ether of the apping surfaces,l a .work plate parting relative movement between .the la'pf .plates and thework plate. in more thannionel' direction, whereby the opposite surfaces of the .pieces carried by thetwork plate willj be subjected to the abrasive `action of thel '12o lapping surfaces of the lap plates. v
3.- A lapping machine having parallel la. plates with flat abrasive opposingsurfaccs mounted so the distance between thenicanv be decreased, guides Vfor insuring the paral- 12:.- lelism ofthe lap in surfaces at all times, adjustable sto s ibi? limiting the closing together of the lgapping surfaces, a work plate between the la plates, andlneans for mov-- ing the work p ate between .the lap plates in luft more than one direction, whereby the opposite surfaces of the pieces carriedby the work plate will be subjected to the abrasive action of the lapping surfaces of the lap plates.
4. A lapping machine having parallel lap plates with fiat abrasive opposing surfaces, one of which is movable toward the other, guides for insuring the parallelism of the lapping surfaces at all times, adjustable stops for limiting the closing of said movable lap plate toward the other lap plate, a work plate between the lap plates, and means for moving the work plate between the la plates in morethanone direction, where y the opposite surfaces of 'the pieces carried by the work plate will be subjected to the abrasive action of the lapping surfaces of the lap plates,
5. A lapping machine having parallel lap ,plates with flat abrasive opposing surfaces mounted so the distance between them canv be decreased, uides for insuring the parallelism of the lappin surfaces at all times, adjustable sto s for l(limiting the closing together of the apping surfaces, a work plate between the lap plates, and means for imparting relative rotary movement between the vlap plates and the work plate in more than one direction, whereby the opposite surfaces of the pieces carried by the work plate will be subjected to Jthe abrasive actioigg of the lapping surfaces of the lap plates.
6. A lapping machine having parallel lap plates with fiat abrasive opposing surfaces mounted s oj-the distance between them can be decreased, uides for insuring the parallelism of vthe la-pping surfaces at all times, adjustable sto s for limiting the closing together of the apping surfaces, a work plate between the lapl lates, and meansfor rotatin the work 'p ate about ,its-,axis and revo ving the axis of -the wokplate between thelappllates, whereby vthe' opposite surfaces of t e pieces carried by -tlie'work plate willbe subjected-to the abrasive action of tliela. ing surfaces of the'ilap plates. lapping machine -having parallel lap plates vwith fiat 'abrasive opposing surfaces,
one of whichlismovable toward `the other,
-guides forl insuring the parallelism 0f the appingv surfacesat all timfS,. 4adjustable stops for limiting the closing oflsaid mov- 'able lap plate toward lthe other llap plate, a work plate between the *lap plates, and
guides for insuring the parallelism of the means for rotating the work plate about its axis' and revolving the axis of the work plate between the lap plates, whereby the opposite surfaces of the pieces carried by the work plate will -be subjected to the abrasive action of the lapping surfaces of the lap plates.
8. A lapping machine having parallel lap plates with flat abrasive opposin surfaces, one lap plate being stationary' an the other movab e toward the stationary plate, guides for the'movable plate mounted on the stationary plate for insuring the parallelism ofthe lapping surfaces at all times, adjustable stops mounted on the movable plate for limiting the closing of said movable plate toward'the stationary plate, a work plate between the lap plates, and means for rotatsurfaces, a work plate between the lap plates, and means for rotating the work plate about its axis and revolving the axis of Ithe work plate between the la plates, whereby the opposite surfaces of tlie ieces carried by the work plate will be subjected to the abrasive action of the lapping sur faces of the lap plates.
10. A lapping machine' having parallel removable. annular lap plates with/flat abrasive opposing surfaces mounted so the distance between them can be decreased,
lappin suifacesat all ltimes, adjustable stops or limiting the closing vtogether of the lapping surfaces, a work plate between the lap plates, and means for rapidly rotating the lwork plate aboutits axis and slowly revolving the axis of the work plate between the lap plates, whereby the opposite surfaces of the pieces carried by the work plate will be subjectedto the abrasive action the lapping surfaces of the la lates.
. DWARD A. SUSIRKROPJ- vico 1-
US21007218A 1918-01-02 1918-01-02 Lapping-machine. Expired - Lifetime US1257046A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2653422A (en) * 1949-08-23 1953-09-29 Crane Packing Co Lapping machine construction
US3380198A (en) * 1965-05-20 1968-04-30 Takada Susumu Parallel plane honing equipment
US3395494A (en) * 1965-05-25 1968-08-06 Leland T. Sogn Lapping machine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2653422A (en) * 1949-08-23 1953-09-29 Crane Packing Co Lapping machine construction
US3380198A (en) * 1965-05-20 1968-04-30 Takada Susumu Parallel plane honing equipment
US3395494A (en) * 1965-05-25 1968-08-06 Leland T. Sogn Lapping machine

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