FR2515547A1 - ABRASIVE TOOL WITH A FIXED DIAMETER ONLY FOR MACHINING A ROTATION BORING AND AXIAL MOVEMENT - Google Patents

Abstract

A TOOL CUTTING IN A SINGLE PASS ACCORDING TO THE INVENTION INCLUDES A BODY 20 WITH SEVERAL GUIDING SURFACES AND DELIMING RECESSES 26 AND MEANS 28, 30 FOR GUIDING ABRASIVE STONES 22 IN ADJUSTABLE CUTTING POSITIONS WITH A FIXED DIAMETER. A CONICAL SHAFT 16 COMES IN CONTACT WITH INNER SURFACES 46 OF SANDSTONES 22 TO DEFINE THE DIMENSION OF THE CUTTING PART, AND ADJUSTABLE MEANS 52, 54 ARE PROVIDED FOR THE RELATIVE TRANSLATION OF SHAFT 16 AND INNER SURFACES 46, FOR ADJUST THE DIMENSION IN ITS DIMENSIONAL POSITION. THE EXPANDABLE TOOL STRUCTURE IS PARTICULARLY SUITABLE FOR ABRASIVE TOOLS AND INCLUDES ABRASIVE PARTICLES HELD ON THE CUTTING SECTION.

Description

Single-pass abrasive tool with fixed diameter The invention relates to a

  single-pass adjustable tool comprising a multi-layer abrasive cutting part and a translatable moving shaft for adjusting and fixing the dimensions of the cutting part. Patents relating to the prior art describe extensible cutting tools having a cutting portion

  which is adjusted when the tool is rotating and inserted

  This is how, for example, Emerson's US Pat. No. 1,791,491 discloses a US Pat.

  a sharpening tool with a shaft urged by a res-

  spell that aligns the tool for multiple passes as the tool is rotated and moved

  axially in a bore-in order to gradually expand-

  the bore during each pass of the same material.

  However, Blaylock US Patent No. 4,075,794 discloses a

  multi-pass sharpening tool with a conical shaft

  that aligns the tool when it is rotating and moving

  axially inside a bore to be machined, and which

  comprises a spring arranged axially for the purpose of

  the stone to the outside of the machined body.

  The object of the invention is to provide a tool for

  advanced one-pass cut for machining

  wise Dar rotation and axial movement in one pass

  of the tool through the bore, in order to remove a quantity

  determined quantity of material, after which the piece is trans-

  if necessary, to another workstation for

  another removal of material by means of a similar tool

  in which the tool comprises a cutting portion and an adjustable shaft which adjusts and sets the dimensions of the

  diameter of the cutting part for machining the bore

  ge, depending on the size required for a single

  pass through and ensure that the tool is well received

  swimming. According to one embodiment of the invention, the tool comprises a cutting part provided with several abrasive stones with a cutting section adjusted in position by a shaft housed inside the body of the tool and associated with surfaces. inclined positioning

  of stone by a relative translational movement of

  to dispose the cutting part according to a diameter of

  desired cut, for a single pass.

  face of the tree has a diameter greater than the diameter

  defined by the space between a part of the small

  of a positioning surface of the abrasive stones of the cutting part, and smaller than the diameter of the

  cutting cylindrical section of the cutting part, the

  able to be held freely in a stable position

  compared to abrasive stones, to preserve

  This type of tool structure ensures correct alignment of the tool during rotation and axial movement.

  of the tool in a single pass in the bore to be machined.

  Initial tool setting and calibration to compensate for wear adjusts the cutting portion to the required size in a single pass so that the bore is machined to the desired size and provides alignment

  correct tool during machining.

  In a preferred embodiment, the

  The cutting tool comprises a simple conical shaft positioned axially with respect to the tool body by means of a threaded shaft connected to said shaft and screwed into a nut fixed to the body. The conical surface of the cone is in contact with the body. inclined surfade of each stone

  abrasive materials for their positioning, so as to de-

  Linir a single-pass cutting diameter Circular springs housed in annular grooves of the body and

  grooves of the stone keep the stones in the

  the body during rotation and movement of the tool in a single pass through the bore Wear is

  compensated by adjusting the position of the shaft by transla-

  of the latter in relation to the cutting part, of

  to bring it to a pre-set cutting diameter for material removal from the bore in a single pass.

  The tool produced according to the invention is Darticu-

  intended for use in abra-

  although other applications are possible:

  in a preferred embodiment, a single body

  block of the tool has several recesses for the handlebar

  as soon as stones in the radial and axial directions, defined

  A conical inner surface on each of the stones makes it possible to mount the stones on a conical shaft. The rotational axial translation movement between the shaft and the stones determines the dimensions of the tool.

  the initial dimensioning of the tool to be used, and always

  The wear of the abrasive particles can be compensated by a movement of the tree Dar compared to the stones in

  to maintain the dimensions of the tool for removal

  material in one pass.

  The objects, features and benefits of

  the invention is clear from the description below.

  after the best embodiment of the invention with reference to the accompanying drawings in which: Figure 1 is a longitudinal sectional view of a cutting tool made according to the invention and which, according to the representation, is mounted in a rotary chuck and axially movable; FIG. 2 is a sectional view of the tool along the line 22 of FIG. 1, seen in the direction of the arrows:

  FIG. 3 is a sectional view along the line

  Figure 3-3 of Figure 1, seen in the direction of the arrows; Figure 4 is a side elevational view of another embodiment of the invention; Figure 5 is a rear elevational view of the embodiment of the invention shown in Figure 4; FIG. 6 is an enlarged partial view in

  elevation of a cutting tool holder in the mode of

  Figure 4; Figure 7 is an enlarged partial sectional view along the line 7-7 of Figure 5, seen in the direction of the arrows; Fig. 8 is a side elevational view of a diamond abrasive tool in the embodiment of Fig. 4;

  FIG. 9 is an end view in elevation.

  the tool shown in Figure 8; and FIG. 10 is a perspective view of

  the tool shown in Figure 1.

  A single-pass cutting tool 10 made in accordance with the invention is shown in FIGS. 1 to 3 of the drawings. The tool 10 is mounted in a mandrel 12 for rotation around an axis, to perform 1 machining. in a single pass of a bore by axial movement of the tool through the bore The cutting tool 10

  comprises a plurality of adjustable cutting parts 14, an armature

  16 and a threaded adjustment pin 18 at the end.

back of the tool.

  As is apparent from FIG. 2, the cutting tool 10 comprises a one-piece body 20 made of a suitable metal such as steel. The body of the tool 20 comprises several abrasive stones 22 with a curved cutting surface 24 abrasive particles such as diamond or cubic boron nitrite attached thereto

  in an appropriate manner to define an abra-

  layer, which increases the abrasive volume

  sand during the finishing process.

  The tool 10 is used in a single-pass operation, during which it is introduced into the bore of a workpiece to remove material in a single pass, and is removed from the bore during a withdrawal cycle Finishing operations in a single trap of this kind allow calibrating the bore

  in close tolerances of dimension, cylindrical

  as well as that will be exluded, the

  til 10 is preset to a fixed diameter to prevent the execution of oversized bores.

  10 is introduced into the bore of the Piece, it is

  dragged in rotation to generate the diameter

preset through the bore.

  In general, the removal of material

  during each pass is relatively small and

  up to a maximum of one hundredths of a millimeter When the removal requirements exceed those achieved by the material removal in a single pass, additional tools are arranged in line with each workstation in a single pass, these tools have a gradually larger diameter, so

  to obtain the desired final bore diameter, without exceeding

  the capacity of each tool for the removal of

  in a single trap Each of the workstations in

  a single pass from the machine can be equipped with a

  measuring system during machining, of the type described in

  U.S. Patent Application No. 126,922 to Paul Fitzpatrick,

asked on March 3, 1980.

  The removal of material in one pass and the repetition of the removal for a number of

  nieces are partly due to the configuration and adjustment of

  floor of each abrasive stone 22.

  Indeed, the horn Ds 20 has three recesses

  26 spared at intervals on its nériphérie each évide-

  26 receives a stone 22 Parallel sidewalls

  28 and 30 of each recess 26 are in contact and slidably guide the lateral surfaces 32, 34 of each stone 22 The surfaces 32, 34

  firmly immobilize the stones 22 against the neck

  the machine when the tool is preset to its

  In the same way, each recess has opposite end surfaces 36, 38 which support the ends 40, 42 of each stone 22 to prevent the axial displacement of the stones at the end.

  course of movement of advance and withdrawal of the tool 10.

  In addition, each stone 22 has an integral surface

  upper 46 inclined relative to a cutting portion 48 which is limited at its outer end by the surface

curved cut 24.

  The surfaces 46 are in contact with the conical outer surface 50 of the shaft 16, so as to adjust

  the surfaces 24 according to a preset cutting diameter.

  The shaft 16 is adjusted by means of a threaded shaft 52 secured to the end 54 of small diameter of the shaft 16 by means of a counter nut 56 The shaft 52 is screwed into a nut 58 which is housed in a counterboring 60 of the body 20 Three pressure screws 62 in the body 20,

  spaced at regular intervals on the periphery,

  trent in grooves 64 formed in the nut 58, so as to block against the relative rotation

  of the body 20 Therefore, the rotation of the shaft 16

  will drag its relative translation with respect to the surfaces 46, so as to adjust the abrasive stones according to the preset diameter desired for the removal of material

one pass.

  The outer diameter of the end of the large diameter of the shaft 16 has grooves 66 formed

  at a precalibrated peripheral spacing desired,

  A spring-loaded piston 68 which is housed in an end bore 69 of the body 20 penetrates and exits the splines 66 This is a reflection of a predetermined rate of change in the diameter of the cutting portion for each increment of rotation of the shaft. causes an audible signal and the maintenance of the adjusted position of the shaft 16 and makes it possible to calibrate the diameter change for

compensate for stone wear 22.

  Each of the abrasive stones 22 is held within the side walls 28, 30 of the recess and the end surfaces 36, 38 by means of a set of

  ring springs 70, 72 which are housed in grooves

  bent 74, 76 in the body 20 to

  axially spaced grooves Each of the abrasive stones also has spaced grooves 78, 80 arranged

  in the alignment of the grooves 74, 76 to house the res-

  spells 10, 72 basically inside the surfaces of

  section 24, thus making it possible to adjust the tool 10 according to

  wear without exposing the springs to the process of

chopped off.

  In addition, the body 20 has an extension with an end 82 of a small diameter intended for

  be housed in a mandrel and a part of inner diameter

  intermediary 84 which supports in a sliding way a

  free-buffer of the type described in US Patent No. 126,922

cited previously.

  During the working cycle, the shaft 16 is rotated, so that the nut 56 and the axis 52 cause the translation of the shaft 16 in the direction

  axial inward or outward of body 20.

  The movement of the shaft 16 into the body increases the diameter of the cutting parts 14 for 1 material removal in one pass.

  removal of the shaft 16 from the body 20 reduces the di-

  meter of common parts 14 This characteristic of

  setting can be adapted immediately to the system of

  automatic setting of tools, on which the rotation of the shaft and its subsequent translation are achieved by the introduction of a rotary compensation axis 86 in

  a bore 88 formed in the extension 80.

  Another embodiment of the invention is shown in FIGS. 4 to 9 which show a tool 90

  pre-settable with a single-pass fixed diameter.

  takes a one-piece body 92 with several recesses 94

  arranged at spaced locations on the circumference.

  Each recess has spaced side walls 96, 98 serving to support a pair of inserts 100 A side 102 of an abrasive part 100 is in particular supported

  on the wall 96 An opposite side 104 of another

  100 range is supported on the wall 98 sides oppo-

  102, 104 of the pair of inserts 100 are in

  contact with the sides 106, 108 of a flange 110.

  As can be seen from Figure 5, each

  of 110 is wedge-shaped and is held in place by means of a pair of screws 112, 114 to make the parts

  abrasives 100 integral with the body 92, so as to delimit

  miter a fixed diameter cutting part as de-

  finished by the cutting surfaces 116 on the pieces 100.

  Fixed diameter adjustment is achieved by a

  relative translation movement between an inclined surface

  118 at the bottom of each recess 94 and a surface area

  than 120 at the base of each insert 100 To increase

  the diameter of the tool, each flange 110 is

  of the shoulder 122 within each flange 110

  by means of the locking screws 112, 114

  100 are unobstructed and can be moved freely.

  in the axial direction to the right, as indicated on

  Figure 5 This movement causes the movement of

  These 100 out of the recesses 94 The increase in the diameter of the tool is obtained by a reverse movement of the parts 100 After adjustment, the flanges 110 are wedged against the inserts, so as to maintain the desired diameter after screwing sufficiently the screw 112, 114 in

  the body so as to be in firm contact with the

plainly 122.

  The embodiments of FIGS. 1 to 3 and FIGS. 4 to 9 previously described relate to fixed diameter cutting tools specially designed for

  be used in finishing operations in one

  passes to improve the precision in diameter, the rec-

  t: itude and the cylindricity of the bores.

Claims (8)

  1 abrasive tool with a single pass, characterized   in that it comprises a body, cutting means   tible to be fixedly connected to the body in order to   hold a single pass cut diameter to remove   a determined quantity of material from the bore of a piece   this during an axial and rotary movement in one pass   of the tool in the bore, said cutting means comprise   a plurality of abrasive stones each provided with an abrasive cutting face and each stone having guiding bearing surfaces on said body, each stone comprising   in addition, an axially inclined positioning surface   leaning surface means with relative inclination   provided in said body and capable of coming into contact with each of said positioning surfaces and of being relatively displaced in the axial direction with respect to each of said positioning surfaces, so as to adjust the diameter of said cutting means, and adjusting means for making said cutting means integral in a position of adjusted diameter,   said cutting means being adjustable according to a di-   initial cut meter with a single pass and readjusted to   a single-pass diameter to compensate for wear.   2 abrasive tool with a single pass, characterized in that it comprises a tool body, cutting means may be fixedly connected to said body so as to maintain a single-pass cutting diameter for the removal of a determined amount of material in the bore of a workpiece during axial and rotational movement of the tool in a single pass through the bore,   said cutting means comprising a plurality of abra-   s.ives each equipped with a curved cutting face and each   one having axially and peripherally guided bearing surfaces on said body to counteract torque and axial thrust during removal   the matte of the piece, each stone   their axially inclined positioning surface, a shaft housed in said body, having an end with   a large diameter extending from said body and   taking a conical surface likely to come into contact with   tact with each inclined positioning surface   and to be displaced axially in relative   port to said positioning surfaces for adjusting the diameter of said cutting means, and adjusting means for securing said cutting means to an adjusted diameter, said cutting means being adjustable to a diameter   initial cut with a single pass and readjusted to the diameter   be cut to a single pass to compensate for wear.   Tool according to claim 2, characterized in that each of said positioning surfaces of   stone has an outer end with a space, a   of the conical surface of said shaft has a larger diameter   the diameter defined by the space formed between the ex-   outer trenities of said positioning surfaces   of stone and smaller than the diameter of the cut faces   curved cutting means, while the shaft can be held freely in a fixed readjustable position   compared to abrasive stones to readjust the diameter be of initial cut to a pass.   4 Tool according to claim 2, characterized in that said shaft, having a simple conical configuration, is positioned axially relative to the body of the tool, the conical surface of the cone coming into contact with said inclined positioning surfaces of each of said stones abrasives for their placement   in order to define the cutting diameter with a single step   said body and said abrasive stones having outer grooves, circular springs are accommodated in said grooves of the body and said grooves of said   stones so as to maintain the stones towards the   against the shaft during the axial and rotational movement of the tool through the bore, and in that adjustable means are provided to maintain said shaft in ilace, said shaft and the circular springs holding said stones together. to keep the   cutting diameter to one pass and prevent the movement   the stones during the movement of the tool   in one pass through the bore of the part.   Tool according to claim 1, characterized   in that it comprises a one-piece body with several   forming means for guiding stones radially and axially so as to define a part   fixed configuration counter, each stone having   two layers of abrasive material, each of the locating surfaces having an inner conical surface   on each of the stones, a conical tree coming in   said wear surface of the abrasive particles can be compensated for by the movement of the shaft relative to the stones so as to readjust the size of the tool to the initial material removal diameter in one only one passes, said multiple layers   of abrasive material increasing the volume of abrasive material   It can be used to compensate for wear.   Tool according to claim 1, characterized   in that each of the stones has at least one side surface   in contact with the body, two pairs of   said stones having a space between them, a flange   neiform is housed in said space, and means are provided for immobilizing said flange against said body, so as to make it integral with said stones in   several axial positions in said body, said   inclined bearing face and said positioning surface acting together when said stones are in said multiple axial positions, so as to   variable adjustment of the cutting diameter to only one the pass of said cutting means.   Tool according to claim 1, characterized in that said bearing surface means comprise 15547   a rotary surface, said adjustment means comprises   rotary threaded means capable of   by rotation of said bearing surfaces for   axially said means of the bearing surfaces.   8 Tool according to claim 2, characterized in that said shaft is rotatable-relative   in relation to the body, it has a small end   meter and means including a screw thread on   the small diameter end of the tree that are likely to   able to operate after rotation of said shaft,   to move it axially with respect to the body.   Tool according to claim 7, characterized in that said adjusting means comprise several   splines formed in said surface means of ap-   and keys in said body are biased by a spring towards one of said splines, so as to maintain said bearing surface means in relation to audit body.   Tool according to claim 8, characterized   in that said adjustment means comprise several   grooves in the end of the large diameter   meter of said shaft and keys in said body are biased by a spring towards one of said grooves, so as to maintain said shaft relative to said body   and allow precise adjustment of the diameter of the til to compensate for wear.