US2159336A - Lapping machine - Google Patents

Lapping machine Download PDF

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Publication number
US2159336A
US2159336A US29794A US2979435A US2159336A US 2159336 A US2159336 A US 2159336A US 29794 A US29794 A US 29794A US 2979435 A US2979435 A US 2979435A US 2159336 A US2159336 A US 2159336A
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United States
Prior art keywords
lapping
spindle
face
disk
workpiece
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US29794A
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English (en)
Inventor
Frederick H Markwick
Louis F Poock
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SHEFFIELD GAGE Corp
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SHEFFIELD GAGE CORP
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Filing date
Publication date
Application filed by SHEFFIELD GAGE CORP filed Critical SHEFFIELD GAGE CORP
Priority to US29794A priority Critical patent/US2159336A/en
Priority to GB18153/36A priority patent/GB473784A/en
Priority to FR810014D priority patent/FR810014A/fr
Application granted granted Critical
Publication of US2159336A publication Critical patent/US2159336A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B5/00—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor
    • B24B5/02—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work
    • B24B5/04—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces externally
    • B24B5/045—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces externally with the grinding wheel axis perpendicular to the workpiece axis

Definitions

  • This invention relates to lapping machines.
  • One of the principal objects of the invention is the provision of a lapping machine of simple construction that is readily adjustable for operation on work pieces within a wide range of size variation.
  • Another object of the invention is the provision of such a lapping machine upon which a single workpiece may be quickly and accurately lapped.
  • Another object of the invention is the provision of a lapping machine having a flat rotatable lapping disk that is adjustably movable to different paths of travel for coordinated movement with a particular workpiece whereby an improved in lapping action is obtained and the lap face is maintained flat for an extended period of usefulness.
  • Anotherobject resides in the method of lapping a workpiece of circular cross section that is rotated on its own axis by engagement with a rotating lapping surface, and is additionally moved with respect to the lapping surface so that the zone of contact is substantially the entire lapping surface.
  • a further object of the invention is the provision of a lapping machine having a work support of such character that the workpiece, while securely held, is free to move into proper operating relationship with the lap face.
  • Fig. 1 is a plan view of the lapping machine constructed in accordance with the present invention
  • Fig. 2 is a transverse vertical sectional view V taken on the line 22 of Fig. 1;
  • Fig. 3 is an enlarged fragmentary view of a portion of the work support
  • Fig. 4 is a sectional view as indicated by the line 4-4 of Fig. 1; a
  • Fig. 5 is an enlarged fragmentary view of a portion of Fig. 4.
  • Fig. 6 is a fragmentary view showing a modified form of lapping disk.
  • the lapping machine is illustrated as comprising a bed I0 having suitable supporting legs H and I2.
  • a head I3 that supports a 55 lapping member, shown as a disk l4, and toward the opposite end of the bed is mounted a work support that is designated generally by the numeral I6.
  • the mounting for the lapping disk is shown as comprising a member I8 that is fixedly attached to the bed I!) and'has spaced upstanding arms I9 incorporating bearings for free rotation of a spindle 2
  • the end of the spindle extending toward the center of the machine projects beyond its bearing 20 for attachment of the lapping disk.
  • Driving means are provided for the lapping disk in the form of a stepped cone pulley 23 which is fixedly mounted on the spindle intermediate the arms 19 and is adapted to carry a belt connecting to a suitable source of power.
  • That portion of the spindle to which the lapping disk is attached terminates in an enlarged end 25 having a flat end face 26 against which the lapping disk is adapted to rest.
  • the face 26 is accurately machined to afford a flat surface that is perpendicular to the spindle axis.
  • a slot 21 is provided in the end piece 25 and extends across the end face 26 on a diameter thereof. This slot is widened adjacent its bottom portion as indicated at 28 for reception of the head 29 of a threaded member 30 that attaches the disk M to the spindle.
  • the member 30 is adjustably slidable in the slot and may be fixedly held at any desired position therein.
  • the lapping disk [4 which is preferably made of cast iron or some such material that is suitable for use as a lap, has a circular peripheral edge 32 and parallel flat end faces; the end face 33 lying in surface contact with the face 26 of the part 25 and the opposite face 34 serving as the lapping face with which a workpiece is engaged during the lapping operation.
  • the disk has a central circular opening 35 therein which, toward the lap face 34, is widened into an annular recess as indicated at 36.
  • a sleeve 31, which is receivable on the member 30, serves as a bearin for the lapping disk.
  • One end of the sleeve has a projecting flange 38 which overlies the disk opening 35 within the recess and serves to hold the disk against the plate 25.
  • a nut 40 which engages the member 30, serves to hold the sleeve in clamped engagement on the end face of the part 25.
  • the recess 36 is of suflicient depth to accommodate the projecting parts of the attaching means below the plane of the lap face 34.
  • the proportioning of the sleeve parts. is such that the disk l4 may rotate with respect to the spindle upon which it is mounted.
  • the disk H has a running fit on the sleeve.
  • the sleeve length under the flange, although such as tohold the diskin surface engagement with the end-face 26, affords sumcient freedom that the disk may rotate independently of the spindle.
  • the work support I6 is shown as comprising relatively movable interfitting plates 48 and 4
  • is in the form of interlocking ways common to machine tool practice and as indicated at 42.
  • the ways stand so that the path of travel of the movable part is transverse to the spindle axis.
  • is a block 44 that is provided with interfitting ways 45 slidably engaging and supporting a carriage 46 for adjusting movement in the direction of the spindle axis.
  • is by means of screws 48 that extend through curved slots 49 in the block and threadedly engage the plate 4
  • the slots 49 are curved on a radius as defined by an imaginary center existing at the midpoint of the screws 48.
  • the slots are of sufficient length to permit a slight amount of angular movement of the block 44.
  • the block 44 intermediate the ways 45 is an upwardly extending projection 58 which is threaded to receive a screw 5
  • has fixed to it a crank 58 for rotation thereof whereby thecarriage may be moved with respect to the block in the direction of the spindle axis.
  • the carriage 46 has an upwardly extending projection 55 that is provided with 'an opening 56 extending coaxial with the spindle for attachment of a. yoke-shaped member 58 that in turn serves as a support for a work carrying frame. The proportioning of the sev-.
  • the yoke shaped member 58 has projecting from one end thereof a stud 51 which is closely received within the carriage opening 56 and is adapted to be held therein by a nut 59.
  • the stud 51 extends oppositely to and stands substantially midway between spaced parallel arms 68.
  • the pins have conical ends 63 and are axially aligned to engage and pivotally support a work carrying-frame 64.
  • the work carrying frame 64 is arranged as a relativelylong bar like portion 65 having inclined guide faces 66 at the opposite sides of one face thereof for accurately mounting a pair .of adjustable work holding members 61.
  • the bar 65 At the midpointof the bar 65 are provided yoke like one end of a workpiece and each holder includesmeans whereby it may be supported by and adjustably fixed to the part 64.
  • the bar like portion 65 has a slot 16 extending parallel to the inclined faces 66.
  • the slot has an enlarged bottom portion 15 for reception of the head of a clamping member 16 by which the work holders are held tothe frame 64.
  • Each holder 61 has a rockable shaft 11 extending into the lower portion thereof which on the exposed ,end has an accessible crank arm 19 and on the enclosed end has mounted thereon a cam 88 that is engaged by the loop end 8
  • the proportioning of the cam, holding member and parts associated therewith is such that in one position of the cam the holding members may be slidably moved along the bar like portion and in another position the holding members are securely locked in place on the bar like portion 65.
  • the work holders 61 by which the pivot centers I are carried, are adjustably mounted so that the spacing of the centers may be altered to accommodate a wide variety of sizes of workpieces.
  • one of the pivot centers is adjustable in its holder 61 so that it may be readily withdrawn, when desired in order to afford a greater spacing for'attachment or removal of a workpiece from the centers.
  • the right hand center 12 is slidably mounted within a socket 82 of the holding member 61 and has a stud projection 83 that extends through the end of'the socket and has attached thereto a finger piece 85 by which the center 12 maybe moved axially against the tension of a spring 84 that is positioned within the socket and bears against the pivot center urging it outwardly toward the opposite center 12.
  • adjustable holder is such that its center may be held in the withdrawn position when desired.
  • the holder end on the socket axis has a cross slot- 86 of such width to receive the thin disk-like finger piece 85.
  • Locking means are provided The arrangement of the for the right hand center in the form of a screw an upstanding arm 94 which is pivotally mounted at 95 on the machine leg 2.
  • the upper end of the arm 94 has pivotally connected to it at 96 a link 91 which is pivotally connected at '98 to the movable plate 4
  • workpieces of the character that are subjected -to a lapping operation have some provision for mounting them between centers. That is, they either have accurately aligned conical centers for mounting on the supporting centers 12, -or they have a central opening therethrough whereby they may be mounted .on a'suitable arbor which in turn may be mounted on the centers 12.
  • the workpieces are so arranged that they may be carried between the centers 12 in such a manner that the surface that is to I be lapped is concentric to the axis of" rotation of the workpiece.
  • the workpiece that is illustrated in dotted outline comprises acylindrical plug I88 which is shown carried by an arbor
  • the machine is readily adjustable to accommodate workpieces within a wide range of size variation.- These pieces may be shorter or longer than the one illustrated'and the great majority of them will be considerably shorter than the radial length of the lap face so that in any one position of contact with the lap face only a part of the radial length of the face will be engaged.
  • the abrading action of the lapping operation removes metal from the lap face as well as from the workpiece.- A lap, to provide a desired lapping operation, must remain flat.
  • the stud 30 that serves as an attaching means between the lapping disk and its support is carried within a transverse groove 21.
  • the provision of this slotted engagement enables the operator to provide any desired degree of eccentric travel in the lapping disk.
  • the center of rotation of the disk is indicated at I02 and is eccentrically related to the center of rotation of the spindle as indiated by the numeral I03. This association of parts results in a planetary motion being imparted to the disk.
  • Rotationof the disk on the spindle or the change in related positioning of the disk with respect to the spindle occurs as a result of frictional drag produced by contact of the workpiece or by provision of means such as a friction brake I04 which is shown carried by an arm I05 extending from the bed I0 to position the brake so that it may contact with the peripheral edge 32 of the lapping disk.
  • the brake comprises a threaded shaft portion I06 that threadedly engages the bracket and which has on one end thereof a cross pin I01 by which it may be conveniently adjusted.
  • the opposite end of the member I06 is socketed at I00 for reception of a block of some resilient substance such as leather which will frictionally engage the periphery of the lapping disk during its rotation and will momentarily stop the .disk or will at least impart some rotational movement of the disk with respect to its spindle.
  • the brake is adjustable so that the desired contacting engagement may be maintained for different degrees of eccentric positioning of the lapping disk and so that, when desired, the brake may be withdrawn entirely from contacting en-' gagement.
  • the fit of the pivot sleeve 31 within the disk center is such as to hold the disk in surface contact with the end face of the spindle and, although sufliciently loose to permit relative movement, it is likewise sufficiently tight to avoid objectionable shake or vibration.
  • the disk is quite heavy and, although rotatably mounted,
  • the friction brake may be resorted to as a means of altering the disk positioning.
  • the brake may be adjusted so that but a very small relative movement is imparted for each revolution of the disk. However as this occurs for each turn of the disk the wear on the disk is made uniform.
  • the work support is of such construction as to provide a substantial and. rigid support'of the workpiece such that objectionable shake or vibration is avoided, it is likewise so constructed to provide a movable support for the workpiece so that the workpiece may freely assume a proper operating relationship with the lap face.
  • the work carrying frame 64 is free to swing on its pivot centers 63 so that regardless of whether the workpiece has a cylindrical or tapering peripheral face it may readily move to a positioning such that the workpiece properly engages the lap face. Friction means are provided between the frame 64 and its supporting structure to prevent too much freedom of movement at this point.
  • the yoke arms 60 have transverse passages therethrough for reception of contact balls IIO that are urged into contacting engagement with the arms 68 through pressure exerted by a spring III that is compressed between the ball I I0 and a threaded plug H2.
  • the tension afforded by the springs III is only sufficient to overcome an objectionable freedom of movement of the frame 64. Free rotation of the workpiece on its centers is assured by provision of the locking screw 88 which permits the centers to be positioned at a desired spacing to thus avoid an objectionable tensioning to these parts which might result from the tensioning of the spring 84.
  • the machine is flexible in that it is provided with a sufficient range of adjustment to readily accommodate plugs within a wide range of size variation and further, it is so arranged that either cylindrical or tapered plugs may be handled. It is further pointed out that as no special adjustments are required other than an adjustment of the'holding, I device a single workpiece of .a given size may be handled within a unit of time practically no longer than the unit time for a plurality of pieces of the same size.
  • a single lap may be utilized for any plugthat may be accommodated and, as mentioned above,'in the case of unusually long plugs an auxiliary lapping disk may be readily attached. Because of'the irregular and constantly changed motion of the disk with respect to the workpiece uniform wear on the lapping face is afforded and, in addition, a superior and highly polished surface is provided on the workpiece.
  • a lapping machine comprising a rotatable lapping member having a flat lapping face, drive means effective on the lapping member to impartv of the work piece with respect to the axis of rotation of the lapping member, means for holding a workpiece in engagement with said lapping member, and means for moving the work piece across the face of the lapping member to inde- .terminately vary the driving relationship be-' tween the drive means and the lapping member. 2.
  • a lapping machine comprising a lapping member comprising a circular disk having a flat lapping face and having a mounting portion at the center thereof, means for rotatably holding a workpiece having a curved surface of revolution in engagement with the lapping flat face of the member, means for moving the holding means across the face of the lapping member, supporting meansfor the lapping member comprising a rotatable spindle, means' on the spindle slidable transversely of the spindle axis and rotatably supportingthe mounting portion of the lapping gagement with the lapping member, supporting means for the lapping member comprising a rotatable spindle, said spindle havingan end portion extending transversely of the spindle axis and terminating in a flat face extending perpendicular to the spindle axis, and mounting means rotatably carrying the lappingmember by engagement with the central opening thereof and having an interfltting connection with the spindle for support of the lapping member on the spindle with one face of
  • a lapping machine comprising a circular disk-like lapping member having flat parallel faces of which one face is the lapping face, said lapping member having a central opening therethrough terminating in an enlarged recess at the lapping face, means for holding a workpiece in engagement with the lapping member, a rotatable spindle for the lapping member, a sleeve extend- Y plane of the lapping face.
  • a lapping machine comprising a lapping member having a flat lapping face,'means for holding a workpiece in engagement with the lapping member, supporting means for the lapping member comprising a rotatable spindle, means rotatabiy mounting the lapping .member on the spindle with the lapping member flat face extending perpendicularly to the spindle axis, and
  • friction means intermittently operable during a lapping operation to move the lapping member with respect to the spindle.
  • a lapping machine comprising a lapping member having a lapping face, means for holding a workpiece in engagement with the lapping member, supporting means for the lapping member comprising a rotatable spindle, means rotatably mounting the lapping member on the spindle with the lapping face extending perpendicularly to the spindle, and means intermittently engaging the lapping member upon rotation of the spindle to impart relative movement to the lapping member with respect to the spindle. 7.
  • a lapping machine comprising a base, a lapping member comprising a circular disk-like member having a flat lappingface, means on the base for holding a workpiece in engagement with the lapping member, supporting means on the base for the lapping member comprising a retatable spindle, means rotatably mounting the lapping member on the spindle with the lapping member flat face extending perpendicularly to the spindle, and means adjustably supported from the lapping machine to intermittently contact the lapping member in frictional engagement upon rotation of the spindle for momentarily holding the lapping member.
  • a lapping machine comprising a rotatable spindle; a lapping member eccentrically mounted thereon and having driving engagement therewith only by virtue of frictional contact, said lapping member having a lapping face extending perpendicularly to the spindle axis, supporting means for holding a workpiece in engagement with the lapping member, said supporting means comprising a frame having axially relatedpoints of support defining an axis of rotation for the workpiece, means rockably supporting said frame for free turning movement on an axis extending transversely through the axis of rotation of the workpiece and extending transversely of the spindle axis, and means for reciprocating the frame in the direction of the plane of the lapping member face for traverse of a supported workpiece across the lapping face towards and away from the axis of rotation of the spindle.
  • a lapping machine comprising a rotatable spindle having a lapping member providing a lapping face extending perpendicularly to the spindle axis, supporting means for holding a workpiece in engagement with the lapping member comprising a rockable frame having a barlike portion, spaced members adjustably mcvable on the bar-like portion, said members having axially aligned pivot members defining an axis of rotation for a workpiece, said bar-like portion having members extending oppositely from each side adjacent the midpoint thereof and curving toward one another to form a U-shaped yoke of which the member ends continue beyond the axis defined by the axially related pivot members, a movable carriage for the frame comprising yoke-like arms encircling the members of the bar-like portion, and axially related bearing means connecting the yoke-like arms of the frame and carriage on a line extending through the axis of rotation of the pivot members and extending transversely to said axis of rotation and
  • a lapping machine comprising a lapping member having a lapping face, a rotatable spindle supporting said member and frictionally engaged therewith to provide rotation of the lapping member on the spindle during operation, means for rotating said spindle, a work holder having centering means for rotatably supporting a workpiece for movement about an axis extending angularly to the axis of rotation of the spindle, a support carrying said work holder for movement about an axis extending substantially transverse of the work axis, and means for moving the work support so that all of the work which engages the lapping face moves toward the axis of rotation of the spindle or moves away from the axis of rotation of the spindle to indeterminately vary the driving relationship between the spindle and the lapping member.
  • a lapping machine comprising a lapping member supported for free turning movement with respect to a fixed axis, said lapping member having a lapping face, rotatable means frictionally engaging said lapping member and adapted to impart a rotative driving force thereto by virtue of frictional contact therewith which is small enough to produce a substantial frictional slip of the lapping member with respect to the rotatable means dunng operation, and means for holding a curved surface of revolution in rolling contact with the face of the lapping member for rotation thereby and for moving the surface of revolution thereacross as a means of influencing the driving effort acting between the rotatable means and'the lapping member to influence the rotation of the lapping member and vary the rotational relationship between the surface of revolution and the lapping member.
  • a machine of the character described comprising a member having a work engaging lapping face, a rotatable spindle supporting said lapping member eccentrically of the axis of retation of the spindle and frictionally engaged with the lapping member to provide relative rotation during operation, means for rotating the spindle, a work support having centering means for rctatably supporting the work for movement about an axis extending angularly to the axis of rotation of the spindle, and means for moving the work support to move the work across the face of the lapping member and indeterminately vary the driving relationship between the spindle and the lapping member.
  • a lapping machine comprising a lapping member having a flat lapping face, means for rotatably holding a workpiece having a curved surface of revolution in engagement with the flat face of the lapping member, supporting means for the lapping member comprising a rotatable spindle the axis of which is angularly related to the axis of rotation of the workpiece, means eccentrically and rotatably mounting the lapping member on the spindle with the lapping m'em bers flat face extending perpendicularly to the spindle axis and providing driving relationship between the spindle and the lapping member effective only through frictional contact for variation of the driving relationship between the spindle and the lapping member during operation, and means for moving the workpiece across the face of the lapping member.
  • a lapping machine comprising a lapping. member having a lapping face, means for rotat-' ably holding a workpiece having a. curved surface of revolution in engagement with the lap-' ping face, supporting means for the lapping member comprising a rotatable spindle the axis of rotation of whiclris angularly related to the axis of rotation of the workpiece, means adjustably attachable to the spindle at varying amounts of eccentricity with respect to the spindle axis and rotatably mounting the lapping member with the lapping face extending transversely of the spindle axis and providing driving relationship between the spindle and the lapping member effective only through frictional contact such that relative rotational movement of the spindle and lapping member occurs during operation, and means for moving the workpiece across the face of the lapping member.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
US29794A 1935-07-05 1935-07-05 Lapping machine Expired - Lifetime US2159336A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US29794A US2159336A (en) 1935-07-05 1935-07-05 Lapping machine
GB18153/36A GB473784A (en) 1935-07-05 1936-06-30 Improvements in or relating to a method of and machine for lapping a surface of revolution on a workpiece
FR810014D FR810014A (fr) 1935-07-05 1936-07-03 Perfectionnements au procédé de rectification d'une surface de révolution d'une pièce à usiner et machine pour la mise en oeuvre de ce procédé

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US29794A US2159336A (en) 1935-07-05 1935-07-05 Lapping machine

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Publication Number Publication Date
US2159336A true US2159336A (en) 1939-05-23

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US29794A Expired - Lifetime US2159336A (en) 1935-07-05 1935-07-05 Lapping machine

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US (1) US2159336A (fr)
FR (1) FR810014A (fr)
GB (1) GB473784A (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2454597A (en) * 1945-08-22 1948-11-23 Delafontaine Charles Grinding and polishing machine
US2610450A (en) * 1950-03-08 1952-09-16 Crane Packing Co Apparatus for finishing cylindrical articles
US2700259A (en) * 1949-10-10 1955-01-25 Dreyfus Sylvain Process for treating brush bristles

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110774071B (zh) * 2019-11-29 2020-08-25 株洲联信金属有限公司 一种无心磨自动送料装置

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2454597A (en) * 1945-08-22 1948-11-23 Delafontaine Charles Grinding and polishing machine
US2700259A (en) * 1949-10-10 1955-01-25 Dreyfus Sylvain Process for treating brush bristles
US2610450A (en) * 1950-03-08 1952-09-16 Crane Packing Co Apparatus for finishing cylindrical articles

Also Published As

Publication number Publication date
FR810014A (fr) 1937-03-13
GB473784A (en) 1937-10-20

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