FR2466314A1 - MACHINE FOR AFFECTING THE PINS - Google Patents

Abstract

Machine for sharpening spindles. The machine 1 comprises a slide 10 movable in a direction transverse to the longitudinal axis of a spindle 2 to be sharpened and which supports a slide 11 provided with a grinding wheel head 13 as well as a feeler device 29 arranged to determine the position of each tooth of a spindle 2 relative to the grinding wheel 15. Application to spindle sharpening machines. (CF DRAWING IN BOPI)

Description

The present invention relates to a machine

to sharpen the pins.

  Pins are tools that have normal

  a considerable length and have several teeth which, when successively brought into contact with a surface to be machined, give it the desired finish and shape by removing each a predetermined thickness of chip which

  normally varies from one tooth to the next and depends on the

  height of each tooth in relation to the preceding

  you. In addition, since the thickness of the removed chip is

  From one tooth to the next, the distribution pitch of the teeth varies

  also along the spindle. Finally, the profile of the teeth may vary along the spindle depending on the surface shape to be obtained. In this regard, it should be noted that the pins

  are extremely specialized tools whose use is only

  justified for mass production and

  that the pins can be sharpened a certain

many times.

  In general, to sharpen a pin or rather to restore the sharpness of his teeth, we use

  grinding machines of the type in which one de-

  manually place a grinding head in order to sharpen

  the teeth of the spindle one after the other. For this purpose, the

  the operator must visually identify the position of the

  the edge of each tooth, then remove from each tooth the same

  chip thickness while controlling the wheel in such a way

  that its outer periphery does not touch the base of the

between successive teeth.

  Normally, the visual identification of the

  teeth on the grinding wheel leads to errors that automatically lead to variations in

geometric pin.

  The object of the invention is to provide a machine

  not to sharpen the pins in which the position of the tran-

  teeth is identified quickly and extremely

  precisely, regardless of the complexity of the form of the

pin to sharpen.

  According to the invention, there is provided a machine for

  to sharpen the pins of the type which includes a first slide

  grinding bucket adapted to impart to a grinding wheel a movement which moves it away from and towards the spindle in a constant stroke in a direction transverse to the axis

  longitudinal axis of the spindle, the second and third

  movable buckets along two axes forming an angle between them, the axis of movement of the second slider being parallel to

  the longitudinal axis, and a feeler device designed to deter-

  successively undermining the position of the grinding wheel relative to each tooth of the spindle, characterized in that the third slider supports both the probe device

  and the first slide, in that the feeler device

  closes an articulated parallelogram comprising a rotatable frame relative to the third slide about an axis perpendicular to the axis of the spindle and the axis of motion

  the second slide, a tie rod and two elastic cranks

  which link together the tie rod and the frame, and that

  the probe device also comprises a first means of determining

  tection of the movements of the frame around its axis of rotation

  and a second means for detecting the axial movement of the

  the latter comprising coupling means designed to apply positively and successively to the teeth of

  the spindle, elastic means being connected to the frame of

  to move the coupling means towards the

teeth of the brooch.

  Other features and advantages of 1'-

  invention will emerge from the following detailed description

  made with reference to the accompanying drawings which illustrate a non-limiting embodiment and in which: FIG. 1 is a schematic side elevation

  a detail of a pin sharpening machine carried out se-

  The present invention 2 is a detail of Figure 1 on a larger scale and FIG. 3 to 6 show the detail of Figure 1

  during different stages of work.

  Figure 1 shows a part of a machine

  sharpen the pins designated as a whole by 1 and com-

  taking a fixed bench (not shown) on which a pin 2 to sharpen is locked axially in position. The spindle, as seen in particular in FIG. 2, comprises several teeth 3 distributed along the spindle 2 with a pitch P which is normally variable according to a given law, the teeth having an outer surface or back 4 which makes a clearance angle greater than A with the horizontal axis of the spindle 2, a front surface 5 defining a cutting edge

  6 with the surface 4 and making a border clearance angle

  tal B with the perpendicular to the axis of pin 2, an over-

  curved connection face 7 between adjacent teeth and a decalcification

  ge or advance H between adjacent teeth that is normally ver-

tical along the spindle 2.

  In the example shown in the drawings, the

  pin 2 is a round pin attached to the bench (not shown).

  felt) of the machine 1 by means of spikes (not shown).

  However, the machine 1 can also be designed to receive

  flat pins mounted directly on the bench.

  The bench supports a fixed upper slide guide 8 for a first slide 9 designed to

  move along the guide 8 under the influence of

  not shown, in a direction X parallel to the

xe of pin 2.

  A second and a third slide,

  respectively 10 and 11, are mounted on the slide

  bucket 9 so as to slide under the pressure of

  respective drive means not shown. The slide

  bucket 10 is mounted on the slider 9 so that it

  slide relative to it in a Y direction practically

  perpendicular to the direction of movement of the slide

  bucket 9 while the slider 11 is a slider

  and is mounted on guides (not shown) connected to the slider 9 in an angularly adjustable manner by means of a pivot 12 and can be locked relative to the slider 9 so as to allow the slider 11 to move in a direction Z which makes an adjustable angle and determined with the perpendicular to the axis of the spindle 2. The slider 11 can be moved by means of drive not represent-

  in such a way that it runs a fixed course towards the ex-

  and in the opposite direction, in the Z direction, between a first position governed by a limit switch

  lla carried by the slide 10 and a second position dé-

  finished closer to pin 2.

  A grinding head 13 is mounted on the neck.

  lisseau 11 and of it extends transversely an axis 14

  on the end of which is wedged a grinding wheel 15.

  On the end of the slider 10 which is

  born to the spindle 2 to be sharpened is arranged a parallel guide 16

  lends to the X direction and supporting a 17 "bile slider

  in one direction or the other along guide 16 under the push-

  a sprocket (not shown) which cooperates with a cremaill-

  ler 18 carried by the guide 16 and is keyed on a shaft (not shown) mounted so as to rotate through the

  slider 17 and provided with a hexagonal actuating head 19.

  A second guide 20 is rigidly connected to the slider 17 perpendicularly to the guide 16 and supports a

  plate 21 movable along the guide 20 under the pressure of a

  gnon (not shown) which cooperates with a rack 22 por-

  20 and is wedged onto a shaft (not shown) rotatably mounted through the plate 21 and provided with a hexagonal actuating head 23. The slider 17 and the plate 21 can be locked along respective guides 16 and 17 by respective blocking devices 24 and 25 actuated by respective hex nuts 26 and 27.

  The guides 16 and 20, the slider 17, the

  than 20, the two pinion and rack couplings and the

  blocking devices 24 and 25 together constitute a

  positive adjustment, indicated by the general reference 28 and by means of which one can adjust, relative to the slider

  , the position of a feeler device designated by the reference

  29 and designed to determine the exact position

a tooth 3 to sharpen.

  The feeler device 29 comprises a lever

  30 formed a first arm 31 substantially located in the Y direction and a second arm 32 perpendicular to the

  arm 31 and secured to the end of the latter which is

  to the pin 2, the oscillating lever 30 is mounted manually.

  to be able to turn on a pivot 33 secured to the

  than 21, it is perpendicular to the last and to the bro-

  2 and engages by being able to turn in a passing hole pre-

  seen in the center of the arm 32 The arm 32 is in the form of a bar with a parallelepiped section and constitutes the frame of a parallelY

  lograEime articulated élas-tick 34 whose ina-niîvelles fate ex-

  two elastic bands 35 are drawn towards the spindle 2 in part of the lateral surface of the arm 32 and the thread of which is formed by an end portion of a papermaking rod 33 parallel to the arm 32, pointing towards the grinding wheel 15 and provided at the opposite end to that which is connected to the belts 352

  a tooth or pawl 37 directed towards the spindle 2.

  The feeler device 29 also comprises a

  linear motor 33, in this case of the pneumatic type

  tick, supported by the plate 21 and comprising a rod of

  39 output mobile between a limit position retracted in the-

  what a roller mounted so as to be able to turn on the ex-

  free end of the rod 39 is separated from the arm 31 of the oscillating lever 30 and an extended position in which the roller cooperates with a side surface of the arm 31, facing the grinding wheel 15 and, overcoming the restoring force of a spring 40

  stretched between the free end of the arm 31 and the plate 21 main-

  holds a protrusion 41 of the arm 31 in contact with one of the lateral faces of a hexagonal stop cam 42 rotatably mounted on the plate 21 by means of a

eccentric pivot 43.

  Stopping the rod 39 in both positions

  mentioned is detected by a sensor 44 mounted on one end.

  mite of the linear motor member 38.

  Finally, the feeler device 29 comprises two linear differential electronic transducers 45 and 46

  the first of which is arranged on the plate 21, on the side of the

  motor 38 and includes a movable rod 47 whose end

  tee is adapted to contact the side surface of the arm 31 facing the grinding wheel 15 while the second transducer is disposed on the plate 21 on the same side of the

  arm 31 as the cam 42 and comprises a movable rod 48 whose

  free end is designed to make contact with the former

  tremity of the probe rod 36 which is opposed to that which

carries the ratchet 37. -

  In operation, the sharpening of pin 2 set

  xialement to the bench (not shown) of the machine 1 is previously

  development stage that has absolute importance

  for the proper execution of the following grinding cycles.

  The machine 1 is made to focus on the first tooth of pin 2 from the position

  of Figure 6 and after putting out of action all the dis-

  positive automatic control that the machine can

do not 1.

  Normally, the first operation performed by

  the operator who develops the machine consists of

  the slider 11 around the pivot 12 so that the direction Z of the movement of the slider 11 is perfectly

  parallel to the front surfaces 5 of the teeth 3 to be sharpened. The o-

  pacer then actuates the slider Il by moving it in

  direction of pin 2 until it reaches its

  limit, then it actuates the slider 10 so as to de-

  place the slider 11, locked in its limit position,

  that the periphery of the grinding wheel 15 is close, without contact, with the curved surface 7 which precedes the first

tooth 3 to sharpen.

  After having locked the slider 10 in the aforementioned position, the operator moves the slider 11 back until it actuates the microswitch 11a.

  and it actuates the driving member 38 so as to bring the

  age 39 at its retracted limit position. In this way,

  operator releases the swing lever 30 which rotates under the

  thrust of the spring 40 around the pivot 33 until it has

  a position similar to that of Figure 4.

  this position, the lateral surface of the rod 36 is in contact with

  tact with the cutting edge 6 of the first tooth 3 of the spindle 2 and compresses the rod 48 of the transducer 46 while the arm 31 of the oscillating lever 30 compresses the rod 47 of the transducer 45. As is the case normally for all the transducers linear transducers, the transducers 45 and 46 are designed to emit a varying electrical signal

  linearly with the axial position of their movable rod,

  be a maximum positive value corresponding to the position taken by the movable rod in the absence of stress and after passing through zero a maximum negative value which corresponds

  at an intermediate position of the movable rod.

  When the rod 36 is in the indicated position

  4, on the first tooth 3 of pin 2,

  the signals emitted by the transducers 45 and 46 are in general

  the operator reduces them by moving the slider 9 to bring the pawl 37 into contact with the first tooth 3 and then continues the movement in the direction

  X until the wheel 15 is aligned with the frontier surface

  5 of the first tooth 3, in a position similar to

  that shown in Figures 1 and 5.

  The cooperation between the pawl 37 and the tooth 3 causes the axial movement of the rod 36 to stop, so that any further movement of the slider 9 in the direction X has the effect of deforming the elastic bands 35. axial movement of the rod 36 relative to the transducer 46 whose rod 48 is

  moves outward and a rotation of the lever oscil-

  30 about the pivot 33 (clockwise in the drawings), the arm 31 of this lever withdrawing from the transducer 45 and allowing its rod 47 to move outwardly. In other words, the progressive deformation of the bands 35 leads to a gradual reduction, in value

  absolute, output signals of the transducers 45 and 46.

  The operator stops the slide 9 when the sur-

  face of the grinding wheel 15 facing the axis 14 is perfectly

  on the front surface 5 of the first tooth 3 to be sharpened.

  Then, it completely returns to zero the output signals of the transducers 45 and 46 by means of the adjustment device 28. For this purpose, the operator begins by loosening the nuts 26 and

  7 then turn heads 19 and 23 to move the neck.

  slider 17 and the plate 21 along the respective guides 16 and 20 until the plate 21 is placed in a position

  corresponding to a zero output of the transducers 45 and 46.

  The operator finishes the focusing stage of the machine 1 by blocking the plate 21 in this position by means of the

  nuts 26 and 27 and setting a feed value of

  lisseau 9 on a known automatic device (not shown),

  this value corresponding to the chip thickness that the

the 15th must remove at each pass.

  To summarize the above, we can say

  that the development of machine 1 consists in adjusting the

  positive probe 29 so that a zero output of the transducers 45 and 46 corresponds to a perfect alignment of

  the surface of the grinding wheel 15 on the front surface of the first

first tooth 3 to sharpen.

  When the focus is completed, the operation

  The actuator actuates a button (not shown) arranged on the table.

  control panel (not shown) of the machine 1 to

  the automatic grinding cycle described below is started, starting from the position reached during the focusing stage on the first tooth 3 to be sharpened and corresponding to

the position of Figure 5.

  In the automatic cycle, when the output signal of the transducers 45 and 46 is zero, the driving member 38 acts in such a way that its rod 39 applies to the arm 31,

  rotating the swing lever 30 (in the direction of the

  guilles of a watch in relation to Figure 6) until

  that the protuberance 41 comes into contact with the hexagon cam

  the 42 against which she stops. This rotation of the lever

  oscillation 30 has the effect of clearing the pawl 37 of the first

  first tooth 3 and rotate upward the rod 36 (Figure 6) which stops in a position where it is raised

  to a degree that depends on the angular position of the

  42. The function of the latter is precisely to

  adjust the raised position of the rod 36 which

  that 37 has to increase all the more since the grinding wheel 15 used

a small diameter.

  The stop of the rod 39, due to the contact between the protuberance 41 and the cam 42, is detected by the sensor 44

  which activates, successively, the device for automatic advance

  that (not shown) which prints to the slider 9 a movement equal to a constant depth of the grinding wheel 15 and

  a drive motor (not shown) associated with the slide

  bucket 11 which moves towards the pin 2 until the grinding wheel 15 is brought to sharpen the first tooth 3, then withdraws from the pin 2 and stops after the actuation of the

micro switch lla.

  Actuation of the microswitch 11a has the effect that the motor member 38 acts, so that its rod 39

  move to the retracted position, releasing the oscillating lever

  turning 30 (in the opposite direction of the hands of a

  relatively to FIG. 3) under the thrust of the spring 40 until the end of the pawl 37 rests on the back 4

  of the first tooth 3 which has been sharpened previously. -

  Stopping the rod 39 in its retracted position;

  is detected by the sensor 44 which activates a control device (not shown) of two drive motors (no

  represented) slides 9 and 10.

  When the oscillating lever 30 and the rod 36 are in the position of FIG. 3, the signals emitted by the transducers 45 and 46 are certainly different from

  zero, and they are transmitted to the control device (not

  presented) as error signals, so as to provoke

  respectively the actuation of the two motors of

  dragging (not shown) slides 10 and 9 which are

  move until the signals are reduced to zero.

  About the above, it should be noted

  that the value of the signal emitted by the transducer 46 is not

  influenced by very small variations, only by the co-operation

  between the pawl 37 and a tooth 3 of the spindle 2.

  Therefore, the slider 9, driven by the transducer 46, moves (to the right of FIGS. 3, 4 and 5) at a substantially constant speed, to slow down when the

  ratchet 37 comes into contact with the second tooth 3 of the broach

  2 and finally stop when the output signal of the transducer 46 is zero. On the other hand, the value of the signal

  transducer 45 is normally positive when the

  37 (Figure 3) rests on the back 4 of the first tooth 3 of the pin 2, then suddenly becomes negative when the pawl 37 rushes (Figure 4) in the spacing between the first and second teeth. Therefore, the slider, controlled by the transducer 45, moves first to leave the pin 2, then reverses its movement so as to approach the pin 2 until it stops (FIG. 5). when the output signal of the transducer 45 is zero. When the slides 9 and 10 reach the

  new position, the position taken by the wheel 15 re-

  the edge 6 of the second tooth 3 is exactly

  identical to that taken by the grinding wheel 15 relative to the cutting edge 6 of the first tooth 3, in the zero position

  previous, reached during the development stage. Other-

  In other words, the feeler device 29 has controlled the movement

  slides 9 and 10 so that the final movement

  made by the slider 9 is exactly equal to the pitch P between the first tooth 3 and the second and the final movement of the slider 10 corresponds to a withdrawal movement of the grinding wheel 15, relative to the axis of the spindle 2, which is exactly equal to the offset H between the first tooth 3 and the second. As mentioned above, when the position is reached, it automatically follows that the rod 39 acts

* - 2466314

  and stopping the latter in the deployed position (FIG. 6) has the effect that the sensor 44 causes the automatic advance of the slider 9 by a distance equal to the constant depth of

  pass and then operates the slider 11.

  From this moment, the stages described more

  are repeated and the sharpening cycles follow automatically.

  until all teeth 3 of pin 2

be sharpened.

  In the embodiment described above by way of non-limiting example, the pin 2 is fixed and a movement is printed on the wheel 15 along the axis X, but

  of course it is obviously possible to build a machine

  China to sharpen in which pin 2 is moving itself

even along the X axis.

  In addition, although the machine 1 described in

  By way of non-limiting example, be it a machine to sharpen

  completely automatic, it is obvious that the

  The feeler 29 may advantageously be mounted on machines

  Sharpening machines, semi-automatic or manual, that is to say

  on machines in which at least part of the

  along the X, Y and Z axes is not controlled automatically.

  by the feeler device 29.

  With regard to the above, it should be noted that the working capacity of the machine 1 described does not depend on

  so much because it is able to automatically perform

  the grinding cycle when a position corresponding to a zero output of the transducers 45 and 46 is reached, nor because the zero output position of the transducers and 46 is sought automatically, but because of

  that the feeler device 29 allows a simple determination

  full, rapid and extremely precise position in which

  it is necessary to place the grinding head 13 so that the wheel is perfectly aligned with the front surface 5 of the

  tooth 3 to sharpen. In other words, by means of the palatal device

  fear 29, it is possible to sharpen all the teeth of a pin 2 with extreme precision and in the same way, the pin, even after many cycles of sharpening

  its geometric features virtually intact.

  Finally, it should be noted that if we always drive

  described in Figures 3 to 6 to the ex-

  clusion of the actuation of the slide 11, the latter being excluded by a simple operation performed on the control panel (not shown) of the machine 1 and if the output of the

  sensing device 29 is connected to any visual display

  known commercial type, it is possible to operate

  machine 1 as a test bench that can check the geometrical characteristics of any spindle mounted on

the bench of the machine 1.

  Many changes can be made

  to the machine 1 described without departing from the scope of the invention.

Claims (8)

  1. Machine to sharpen the pins of the type that   includes a first grinding slide designed to confer   to a wheel that supports a movement that moves it away and closer to the spindle in a constant stroke in a direction transverse to the longitudinal axis of the spindle, second and third movable slides along two   axes at an angle to each other, the axis of movement of the   xth slider being parallel to the longitudinal axis, and a feeler device designed to successively determine the position of the grinding wheel relative to each tooth of the spindle, characterized in that the third slider (10) supports both the probe device ( 29) and the first   slider (11), in that the probe device (29) contains   me an articulated parallelogram (34) comprising a frame (32)   rotatable relative to the third slider (10)   rotation of an axis perpendicular to the axis of the spindle (2) and to the axis of movement of the second slider (9), a tie rod (36) and two elastic cranks (35) which connect together the   pulling (36) and the frame (32) and that the palmar device   fear (29) also comprises a first detection means (45) of the movements of the frame (32) around its axis of rotation and   a second means (46) for detecting the axial movement of the   trant (36), the latter comprising coupling means designed to apply positively and successively to the   teeth (3) of the spindle (2), resilient means being   linked to the frame (32) so as to displace the means of accou-   in the direction of the teeth (3) of the spindle (2).   2. Machine according to claim 1, characterized   in that the second slider (9) is movable relative to   on the spindle (2) and supports the third bucket (10).   3. Machine according to one of claims 1   or 2, characterized in that the feeler device (29) is supported by the third slider (10) via   means for adjusting the position of the palatal device   fear (29) relative to the third slider (10).   4. Machine according to claim 3, characterized   in that the adjustment means comprise a first guide (16) integral with the third slide and parallel to   the longitudinal axis, a fourth slide (17) assembled from   slidable along the first guide (16), a second guide (20) carried by the fourth slider (17)   and perpendicular to the first guide (16) and a fifth cou-   slider mounted so that it can slide along the   xth guide (20), in that drive means are provided for moving the fourth and fifth sliders along their respective guides and in that locking means (24, 25) are provided to block the fourth and fifth sliders;   fifth slides on their respective guides.   5. Machine according to any one of the   1 to 4, characterized in that each of the cranks   the elastics consists of an elastic band (35).   Machine according to any one of the   1 to 5, characterized in that the feeler device (29) comprises thrust means designed to cooperate with the frame (32) so as to rotate it about the relative axis of rotation, against the action of the means elastic members (40) and that abutment means (42) are provided for stop the frame (32).   7. Machine according to claim 6, characterized   in that the abutment means (42) comprise a   me to polygonal outer profile that can turn around a eccentric axis.   8. Machine according to any one of the   1 to 7, characterized in that the first and second   x detection means are formed of different transducers   respective linear ferentials (45, 46) whose   exits respectively control the movements of the third me and second slides.