FR2526349A1 - METHOD AND MACHINE FOR FORMING A WORK SURFACE SET ON A CAM - Google Patents

Abstract

THIS PROCESS ALLOWS TO RECTIFY A REGULATED SURFACE OF A CAM WHICH WALLS AROUND A LONGITUDINAL AXIS BY MEANS OF THE CYLINDRICAL WORKING SURFACE OF A WHEEL. THE CAM IS MOUNTED TO ROTATE AROUND THE Y-AXIS OF ITS SHAFT, THIS AXIS CAN OSCILLATE AROUND A VERTICAL V-AXIS AND AROUND A HORIZONTAL Z-AXIS. WHEEL 1 TURNS AROUND THE X-AXIS OF ITS SURFACE OF WORK AND IT CAN MOVE IN TRANSLATION PARALLEL TO THE Z AXIS ACCORDING TO ARROW F AND ALSO IN VERTICAL TRANSLATION. CONTROL MEANS LINK THE OSCILLATION OF THE CAM AROUND THE Z-AXIS OSCILLATION AROUND THE AXLE AND THE VERTICAL TRANSLATION OF THE WHEEL TO ITS HORIZONTAL TRANSLATION SO THAT THE RING OF THE REGULATED SURFACE OF THE CAM IN CONTACT WITH THE WHEEL IS PARALLEL TO THE AXIS OF THIS WHEEL.

Description

The invention relates to oroces allowing

  to obtain by rectification a regulated surface which coils

  the around a rectilinear longitudinal axis and forms the sur-

  working face of a cam, as well as machines for implementing this method.

  The invention relates in particular to a process

  dice, and to a machine for the implementation of this process, of the type described in French patent application N O 8 304 255 and Japanese patent application no. 42535/83 filed

  on 16 3 1983 by the same plaintiff.

  The process according to these requests is of the type which

  takes the steps of planning a grinding wheel

  around an axis and has an annulai-

  re, to put the annular working surface of the grinding wheel in contact with the adjusted surface of the cam that one wants to obtain, to put the cam in rotation around its axis, to

  give this axis of the cam an angular oscil-

  lant around an axis of oscillation whose direction is

  fixed, to impart a translational movement to the grinding wheel

  able to move the work surface of the grinding wheel in

  a fixed straight direction, to provide means of

  mande which link together the rotational movement of the cam around its axis, the oscillating movement of the axis of this cam and the translational movement of the grinding wheel so as to constantly maintain the working surface of the grinding wheel in contact with the set surface of

drug.

  Similarly, the machine according to this request is of ty-

  pe which includes a workpiece head supported by the fixed structure of the machine so as to be able to rotate about an oscillation axis whose direction is fixed and on which a workpiece carrier is mounted, the cam to be obtained being mounted on this carriage so as to be able to rotate around its longitudinal axis, a tool-carrying head on which is mounted, so as to be able to rotate around its own axis, a mandrel to which is

  coaxially fixed a grinding wheel, the head

  the tool being slidingly supported by the structure

  fixed to the machine, to allow movement of transla-

  tion of the axis of rotation of the grinding wheel the ong of a trajectory

  roof rectil Igne pcr-established, and control Lovens

  planned to achieve a pre-established relationship between the

  tation l li cam around its longitudiial a> e, nmoive-

  angular position of the workpiece head around the axis of ccs-

  cillation and the translational movement of the holder head

  sliding tool which supports the mandrel, the said relation

  pre-established being suitable for maintaining the work surface

  vail oie the grinding wheel constantly in contact with the surface

g 14 e de la ca ne.

  In the known technique, the process and the machine

  do not of the specified type require the use of a flat

  ne, that is to say who has a work surface containing

naked in a shot.

  The object of the invention is to provide a process and a machine of the aforementioned type which make it possible to obtain by rectification a regulated surface which is wound around a rectilinear longitudinal axis and which forms the surface.

  working of a cam, and which use a cylindrical wheel

  that having a work surface belonging to a cylinder

constant section.

  To achieve this, the object of the invention is

  a spocified type process, characterized in that the over-

  annllary working face of the grinding wheel is constituted by a cylinder with constant circular section having for axis the axis of rotation of the grinding wheel and in that it comprises the complementary phases consisting in printing on the axis of the camie a second movement of angular oscillation around a second axis of oscillation and to be imprinted with a grinding wheel

  a second translational movement along a direction

  fixed recti tion, however provision is made for

  control means which link the second movement of the eye

  angular relationship of the cam axis at the first movement

  angular oscillation of this axis and the second movement

  translation of the grinding wheel at the first movement of translation of the grinding wheel, the action of the control means

  being such that, in each working position of the

  me, the segment of the ruled surface of the latter which

  is in contact with the surface of the furniture

  the is arranged parallel to the axis of the grinding wheel, so

  is that the contact between the working surface of the grinding wheel and the adjusted surface of the cam extends over the whole

of the aforementioned segment.

  To achieve the above-mentioned goal, the

  vention also relates to a machine of the specific type

  shown above, characterized in that the grinding wheel has a cylindrical working surface of constant circular cross-section arranged coaxially with the mandrel, said mandrel being rotatably mounted on a carrier carriage itself

  slidably carried by the grinding wheel post for

  put a second translational movement of the axis of the grinding wheel along a pre-established rectilinear trajectory and

  in that the workpiece carrier, on which the cam

  hold is rotatably mounted, is supported by a plate

  support which is articulated on the workpiece head, for turning

  ner around an axis of oscillation, however it is pre-

  seen control means which link the angular movement

  shut up the workpiece head around its own bone axis

  cillation at the angular movement of oscillation of t 4 te

  workpiece carrier and the translational movement of the carriage

  te-mandrel to the translational movement of the support upright

  grind in such a way that in each working position

  vail of the cam, the segment of the on Eace set from this

  which is in contact with the work surface

  the wheel is arranged parallel to the axis of the

  grinding wheel, so that contact between the working surface

  grinding wheel size and the adjusted surface of the cam

over the entire said segment.

  Other features and advantages of the invention

  tion will be better understood on reading the description

  which will follow from an exemplary embodiment and referring to it

  rant to the accompanying drawings in which,

  Figures 1, 2, 3 and 4 are schematic views

  ques in perspective of the cam to be obtained and the tool wheel shown in different successive phases of the process according to the invention; Figure 5 is a plan view corresponding to Figure 1; Figure 6 is a side view, taken along the

  arrow VI, parallel to the axis of the tool wheel, of the figure

re 5;

  Figures 7, 8, 9, 10, 11 and 12 are figures.

  res analogous to FIGS. 5 and 6 and which correspond to res-

  pectively in Figures 2, 3 and 4; Figure 13 is a view parallel to the axis of the tool wheel representing this wheel and the cam in another phase of the method according to the invention;

  Figure 14 is a perspective view of a ma-

  china suitable for implementing the method according to the invention.

  In 1, we indicated a cylindrical grinding wheel which turns

  ne around an X axis The grinding wheel 1 has a cylindrical working surface 2 with a constant section and coaxial with the X axis The X axis can move by a translational movement along the direction indicated by the arrow F En 3, there is shown a cam having a working surface 4 formed by an adjusted surface, that is to say

  constituted by a set of rectilinear segments La ca-

  me 3 can rotate around a Y axis and its working surface

  vail 4 has a profile that varies continuously

  along the Y axis Cam 3 can rotate around a pre-

  mier V axis perpendicular to the X axis of the grinding wheel 1 The

  me 3 can also rotate around a second Z axis per-

  pendulum to the Y axis and to the V axis At A, we have indicated a plane tangent to the working surface 4 of the cam 3 the

  along a straight segment 5 In 7, we indicated the

  ratrix of the cylindrical surface 2 arranged on the plane

  defined by the X axis of the grinding wheel 1 and by the direction of de-

  placement F of this axis In Figures 1, 5 and 6, the genera-

  ratrice 7 is parallel to segment 5 and is aligned

  on this segment in the direction of movement F By con-

  sequent, if the grinding wheel 1 moves in the direction F, the generator 7 moves until it comes to be superimposed on the segment 5 In B, we indicated another plane tangent to the

  working surface 4 of cam 3 along a rec-

  line 6 With respect to plane A, plane B is rotated by an angle H around the axis Y In FIGS. 2, 7 and 8,

  cam 3 has been turned, compared to the situation illus-

  previously entered, from the angle H around the axis Y, according to

  arrow Hl Under these conditions, plane B is therefore per-

  pendulum to the plane defined by the axis X of the grinding wheel l and by the direction of movement F In FIGS. 3, 9 and, the cam 3 is turned relative to FIGS. 2, 7 and

  8 by an angle K around the Z axis in the direction indicated

  quée by the arrow K 1 Under the effect of this rotation K, the segment 6 is arranged so as to be parallel to the plane defined by the axis X of the grinding wheel 1 and by the direction of translation F of this axis In the figures 4, 11 and 12, the cam 3 is rotated with respect to FIGS. 3, 9 and 10 by an angle L around the axis V, in the direction indicated by the arrow Ll Under the effect of this rotation, the segment 6 is arranged so as to be parallel to the axis X of the grinding wheel 1 Under these conditions, the segment 6 is spaced by a distance E from the plane defined by the axis X of the grinding wheel and by the direction of translation F On Figure 13, the

  grinding wheel 1 has been moved from its position in the figures

  res 4, 11 and 12, of the distance E in the direction indicated

  quée by arrow G which is perpendicular to the direc-

  tion of translation F Under the effect of this second

  translation, the generator 7 of the grinding wheel 1 is located

  hindered on segment 6 in the direction of translation F.

* 2526349

  Consequently, when the grinding wheel 1 moves in the di-

  section F, generator 7 is superimposed on the segment

  6 The description of the process according to Figures 1 to 13 is

  the next In Figures 1, 5 and 6, the grinding wheel moves

  this in translation along the first direction of translation F so as to be brought into contact with the segment 5 Then, the cam 3 is rotated about its own axis Y and, at the same time, the position of the cam 3 is modified, with angular displacements of this cam around the axes -Z and V while the grinding wheel 1 is moved in one and / or in the other direction, in the

  directions of translation F and G These movements of the

  me 3 and grinding wheel 1 are digitally controlled by

  known control means, not shown, in such a way

  re that in each set of related positions of the

  me 3 and wheel 1, generator 7 of the latter

  either in contact with a determined segment of the surface

  slide 4 of cam 3 This operation is shown in the remaining figures 2 to 13 In these figures, taking

  for reference a general plane B tangent to the surface

  glée 4, the correct operating positions of the grinding wheel 1 and the cam 3 are obtained by the rotations H, K, L of the cam 3 and by the translations F, G of the grinding wheel 1 When we know the profile that l we want to get for

  the adjusted working surface 4 of the cam 3, it is possible

  ble to determine for each tangent plane B the corresponding values of the angles of rotation of the cam 3 and the amplitudes of the abovementioned translations of the grinding wheel i In FIG. 14, a machine is shown intended for the implementation of the method described above. above and designated as a whole by 10 The machine 10 includes a base

  11 on which a workpiece head 12 is mounted for turning

  ner around a fixed axis V The workpiece head 1 supports

  a support plate 13 in a manner which allows it to turn

  ner around a Z axis perpendicular to the V axis On the

  support plate 13 is slidably mounted a carriage

  part 14 on which a camshaft 15 is rotatably mounted.

  The shaft 15 can rotate around a perpendicular X axis

  to the Z and V axes and it is rotated by a mo-

  tor 16 A grinding wheel upright 17 is mounted on the base 11 so that it can slide along a direction

  of translation F The direction of translation F is perpen-

  perpendicular to the axis of rotation V of the workpiece head 12.

  The grinding wheel upright 17 is slid by a dovetail guide 18 A mandrel carriage 19

  is mounted on the grinding wheel upright 17 so that

  see slide along a direction of translation G.

  The direction of translation G is perpendicular to the di-

  translation rection F The mandrel carriage 19 is provided with a mandrel on which is mounted coaxially a grinding wheel 1 having a cylindrical working surface with constant circular section and coaxial with the axis of rotation X of this grinding wheel 1 This axis of rotation X is perpendicular to

  the axis of rotation V of the workpiece head 12 and in the direc-

  translation positions F and G Motor means not shown

  felt put the grinding wheel 1 in rotation The operation of the machine 10 is as follows The camshaft 15 is rotated by the engine 16 about its axis Y in the direction indicated by the arrow Hl At the same time, means of numerical control not shown put the support plate 13 in rotation about the Z axis

  in the direction indicated by the arrow Kl and the head

  te-piece 12 rotating around the V axis in the direction

  tion indicated by the arrow Ll In addition, and at the same

  time, under the action of control means with numerical control

  risk not shown, the grinding wheel upright 17 moves

  this along the direction of translation F and the mandrel carriage 19 moves along the direction of translation G Under the effect of these combined movements, the grinding wheel 1 is constantly in contact with the cam 3 of the shaft 15 which is adjacent to it, along one of the segments which constitutes the adjusted working surface of the

cam 3.

  Of course, various modifications can be made by those skilled in the art to the device which comes

  to be described by way of nonlimiting example without for this-

  depart from the scope of the invention For example, being

  born that in order to obtain a correct working coupling

  be grinding wheel 1 and cam 3, the movements described above

  are important as relative movements

  and not as absolute movements, some of the movements

  elements printed on the cam can alternatively be printed on the grinding wheel and, conversely, the translational movements

  of the grinding wheel can alternatively be printed on the cam.

Claims (11)

-R E V E N D I C A T I O N S   1 Process for obtaining by rectification an adjusted surface which is wound around a rectilinear longitudinal axis and which forms the working surface of a cam, comprising the phases consisting in providing a grinding wheel which rotates around an axis and has a annular work surface, to put the annular work surface of the   grinding wheel in contact with the adjusted surface of the cam,   be the cam rotating around its axis, to be printed on   this axis of the cam an angular oscillation movement au-   rotation of an axis of oscillation whose direction is fixed, to impart to the wheel a translational movement suitable for moving the working surface of the wheel in a   fixed straight direction; to provide means of   mande which link together the rotational movement of the cam around its axis, the oscillating movement of the axis of this cam and the translational movement of the   grind so as to constantly maintain the work surface   value of the grinding wheel in contact with the adjusted surface of the cam, this process being characterized in that the working surface of the grinding wheel (1) is constituted by a cylinder with constant circular section (2) having as axis the axis of   rotation (X) of the grinding wheel and in that it includes the   very ohases consisting in printing on the axis (Y) of the cam   (3) a second angular oscillation movement (Kl) above   turn of a second axis of oscillation (Z) and to print on the grinding wheel (1) a second translational movement (G) along a fixed rectilinear direction, however it is   provided control means which link the second movement   angular oscillation ment (Kl) of the axis (Y) of the cam (3) at the first angular oscillation movement (L) of this axis and the second translational movement (G) of the grinding wheel (1) at the first translational movement (F) of the grinding wheel, the action of these control means being such that, in each working position of the cam, the segment (5,   6) of the adjusted surface (4) of the latter which is   ve in contact with the working surface <2) of the grinding wheel (1) is arranged parallel to the axis (X) of the grinding wheel, so that the contact between the working surface of the grinding wheel and the adjusted surface of the cam extends over the entire segment.   2 Method according to claim 1, characterized in that the adjusted working surface (4) of the cam (3) is formed by juxtaposed rectilinear segments each of which is arranged in a corresponding plane which passes   by the longitudinal axis (Y) of the cam (3).   3 Method according to one of claims 1 and   2, characterized in that the first axis of oscillation (V) and the second axis of oscillation {X) around which the first (Ll) and the second (Kl) oscillatory movements of the axis of rotation (Y) of   the cam (3) are perpendicular to each other.   4 Method according to claim 3; characterized in that the first axis of oscillation (V) of the cam is   perpendicular to the axis of rotation (X) of the grinding wheel x 1).   Method according to one of claims 3 and   4, characterized in that the first (F) and the second (G) translational movements of the grinding wheel (1) occur along rectilinear trajectories perpendicular to the axis of rotation (X) of the grinding wheel (1).   6 Method according to claim 5, characterized in that the first (F) and the second (G) movements of   translation of the grinding wheel (1) occur along tra-   rectilinear jectories perpendicular to each other.   7 Machine for obtaining by rectification   tion according to the method of claim 1 a surface surface   which forms the working surface of a cam,   nant a workpiece carrier head supported by the fixed structure of the machine so as to be able to rotate around an axis of oscillation whose direction is fixed and on which is mounted a workpiece carrier, the cam to be obtained being 11. mounted on this workpiece carriage so that it can rotate around its own longitudinal axis, an amount   grinding wheel holder on which a mandrel to which is fixed coaxia-   Lement a grinding wheel is mounted to rotate about its axis, the amount of wheel holder being supported at   sliding by the fixed structure of the machine, for   put a translational movement of the axis of rotation of the grinding wheel along a pre-established rectilinear trajectory and control means intended to achieve a pre-established relationship between the rotation of the cam around its axis   longitudinal, the angular movement of the workpiece head   this around the axis of oscillation and the movement of trans-   lation of the sliding grinding wheel upright which supports the chuck, said pre-established relationship being suitable for constantly maintaining the working surface of the grinding wheel in contact with the adjusted surface of the cam, characterized in   that the grinding wheel (1) has a cylindrical working surface   drique with constant circular section (2) arranged coaxially   LEMENT to the mandrel, said mandrel being rotatably mounted on a mandrel carriage (19) which is itself supported at   sliding by the grinding wheel upright (17) to allow   be a second translational movement (G) of the axis of   rotation (X) of the grinding wheel (1) along a rec-   pre-established line, and in that the workpiece carrier (14) on which the cam to be obtained is rotatably mounted is supported by a support plate (13) which is articulated on the   workpiece head (12) to rotate about an axis of oscillation   lation (7), however that means are provided for   of which link the angular movement (Kl) of the carriage   part (14), around its axis of oscillation (F) when moving   angular oscillation (Li) of the workpiece head   (12) and the translational movement (G) of the carriage   mandrel (19) to the translational movement (F) of the upright   grinding wheel holder (17) in such a way that in each position   tion of the cam (3), the segment (5, 6) of the adjusted surface (4) of this cam which is in contact   with the working surface (2) of the grinding wheel (1) is available   dried parallel to the axis (X) of the grinding wheel, so that the contact between the working surface (2) of the grinding wheel (1)   and the adjusted surface (4) of the cam (3) extends over the to- tality of said segment.   8 Machine according to claim 7, charac-   sed in that the adjusted working surface (4) of the cam, (3) is formed of rectilinear segments (3) juxtaposed, each of which is arranged on a corresponding plane which passes through the longitudinal axis (Y) of the cam.   9 Machine according to one of claims 7 and   8, characterized in that the axis of oscillation (V) of the tg-   the workpiece carrier (12) and the oscillation axis (Z) of the plate   that support (13) are perpendicular to each other.   10 Machine according to claim 9, character-   sée in that the oscillation axis (V) of the workpiece head   this (12) is perpendicular to the axis of rotation (X) of the man- drin grinding wheel.   11 Machine according to one of claims 9 and   10, characterized in that the two translational movements   tion (F, G) of the grinding wheel (1) occur along tra-   straight jets perpendicular to the axis of rotation (X) of the wheel chuck.   12 Machine according to claim 11, character-   laughed at in that the two translational movements (F, G)   grinding wheel (1) occur along rec-   perpendicular lines between them.