FR2521049A1 - DEVICE FOR ACTING ON THE RELATIVE POSITION OF TWO COUPLED ELEMENTS OF A MACHINE TOOL - Google Patents

Abstract

A LATHE INCLUDES A TOOL HOLDER 1 (NAMED HEREIN AS MACHINE ELEMENT) AND A TOOL HOLDER 2 SLIDER (NAMED HEREIN AS MACHINE ELEMENT); EACH OF THESE ELEMENTS CONSTITUTES A STRUCTURE TO BE COUPLED, AND INCLUDES A COUPLING MECHANISM INCLUDING A PRESSURE CHAMBER 10, A COLUMN-SHAPED ELEMENT 11 WHICH IS SUBJECT TO THE PRESSURE OF THE FLUID IN THE FORM OF A UNIFORM TENSION STRESS 'EXERCISING IN THE AXIAL DIRECTION, AND A FIXING DEVICE 15 WHICH CONSISTS OF A RIGID MATERIAL AND ATTACHED AT THE END OF THE COLUMN-SHAPED ELEMENT IN A WAY THAT CAN ONLY BE MOVED IN THE AXIAL DIRECTION; THE COUPLING MECHANISM IS PROVIDED AS ONE PIECE WITH EACH MACHINE ELEMENT TO BE COUPLED THROUGH THE EXTREME PART OF THE COLUMN ELEMENT BASE AND THE FIXING DEVICE SO AS TO CONTROL THE FLUID PRESSURE IN CHAMBER 10 SO THAT THE RELATIONSHIP BETWEEN THE POSITIONS OF THE COUPLING MACHINE ELEMENTS CAN BE CAREFULLY ADJUSTED.

Description

it

  The present invention relates to an ac-

  coupled with components of a machine and, more

  in particular, a coupled structure equipped with a new

  coupling mechanism capable of allowing micro-displacement

  cement which corrects or controls the positioning error

  due to thermal deformation or abrasion between the elements

  coupled elements of a machine tool.

  machine components involved include the so-

  key, the support frame or chassis of the machine itself, the machine chassis or mounting base of various assemblies to be mounted on the machine, for example, in the case o

  the coupling mechanism of the present invention comprises

  te a coupling part of the machine elements which

  have been fixed together previously such that part of

  coupling of the base and the column of a drill or a

  tool holder support coupling, or counter

  doll and their slides, as a result of which, the error

  positioning due to thermal deformation or abrasion

  the machine is corrected without affecting the stiffness

  of the coupling parts, and the operating precision

  the machine can be maintained and, moreover, the

  controlled cross-displacement is applied between machine elements depending on conditions so as to make it more

  many functions of the machine.

  2, In the prior art, being a lathe, the

  tool holder support was either attached to the holder slide

  tool, either mounted in rotation around the axis in the vertical direction of the drawing in Figure 1, and the transfer in the perpendicular direction (in Figure 1, vertical direction of the

  drawing, hereinafter referred to as "direction of the Y axis") to the bro-

  che and the tool shaft was not allowed Therefore

  quent, for example, in the case where one had to perform the machining of a keyway by mounting a cutter

  on the tool mounting shaft, the width of the groove

  re to be machined was a function of the outer diameter of the cutter, and when the cutter was worn, there was

  width reduction In addition, in case you want to

  milk slightly increase the width of the groove

  vette, it was necessary to change the cool

se.

  An object of the present invention is to allow

  maintaining the operating precision of the machine by correcting the positioning error due to thermal deformation or abrasion of the machine without

  affect the rigidity of the coupling parts of the elements

  machine elements by providing a coupling mechanism according to the present invention to the parts where the machine elements are coupled to each other, that is to say the base, the support frame, or the machine's own frame tool, or machine frame or base

  mounting of the various assemblies to be mounted on the ma-

  and, moreover, to allow more performance to be obtained from the machine by ensuring that the

  controlled micro-displacement between various elements of the ma-

  China is done according to the required conditions.

  Furthermore, another object of the present invention

  is to allow the micro-transfer of the holder

  tool-in the direction of the Y axis without affecting the stiffness

  the support and the tool-carrying slide by coupling

  tool holder support and lathe slide to

  by means of a coupling mechanism according to the present invention

  tion, and when a keyway is to be machined, the 3, correction of the dimension error of the groove due to abrasion of the cutter becomes possible and it follows that the keyway can be machined with a precise width. Furthermore, another object of the present invention is to allow automatic control of the value of the micro-transfer of the tool holder support in the direction of

  the Y axis by coupling this support and the carrier slide

  lathe tool by means of the coupling mechanism of the

  present invention, and by providing a set of controls

  of the value of the displacement of the tool holder support, and is to allow automatic correction of the error in the cutting dimensions of the keyway coming from

  abrasion of the bur when the groove is to be used

  born. Another object of the present invention is to

  allow the turning of a keyway of di-

  different mensions with a single cutter, which eliminates the tedious exchange of tool, that is to say the cutter, The present invention will be well understood during

  the following description made in conjunction with the drawings

attached in which:

  Figure 1 is a schematic side view of

  presenting a trick; Figure 2 is a partial sectional view of an embodiment of the case where the coupling mechanism

  of the present invention is used in the delivery part

  tool holder support and carrier slide

  lathe tool; FIG. 3 is a block diagram of a control unit for the displacement value of the

  tool holder support in case the coupling mechanism

  plement of the present invention is used in the coupling part of the door support, tool and the tool holder slide of the lathe;

  Figure 4 is a perspective view shown

  both schematically the milling machine which employs the 4.

  coupling mechanism of the present invention for ac-

couple the column to the base; and

  Figure 5 is a perspective view shown

  schematically the lathe employing the mechanism of

  coupling of the present invention in the coupling part of the tailstock and its slide, and the support

of tool holder and its slide.

  In Figure 1, there is shown a lathe W whose construction is conventional except for a mechanism for coupling the coupling part of the tool holder support 1 and the tool holder slide 2 The lathe W comprises a bench 3 and a mandrel 4 mounted on the spindle The transverse slide 5 is mounted on the bench 3 so

  able to slide in the spindle direction (perpetual direction

  right on the surface of the drawing in figure 1) and the

  tool holder 2 coupled to the tool holder support 1 is mounted on the transverse slide 5 so as to be able to slide to the right and to the left of FIG. 1, and the tool holder slide 2 is produced so as to be able to slide on the transverse slide being driven by a motor 6 The holder for

  tool 1 has a tool mounting shaft 7 and a mill

  8 is mounted on the shaft 7, the shaft 7 is driven in

with a motor 9.

  Tool holder 1 and the slide

  tool holder 2 are coupled by the coupling mechanism

  ment of the present invention which will now be described in detail.

  In FIG. 2, the mechanism is shown in detail.

  coupling mechanism for machine elements 1 and 2 of the machine tool consisting of the tool holder support and the tool slide The mechanism for coupling the machine elements comprises a pressure chamber 10, a

  column-shaped element ll which is subject to pressure

  sion of the fluid in the chamber 10 in the form of a uniform tension stress in the axial direction, and a fixing device 15 made of a rigid material which is fixed to the end 12 of the element ll and is locked to the part 5.

  base 13 of this element so that it cannot be moved

  only axially, and in one piece with the elements

  machine parts 1 and 2, i.e. the holder for

  tool and the tool-carrying slide which are coupled to the base 14 of the element II and to the fixing device 15, whence it results that a micro-position relationship between the coupled machine elements 1 and 2 is made possible by using the elastic deformation of the element 11 due to the pressurized fluid of the chamber 10 As the base 13 of the chamber 11 and the fixing device 15 are locked so that they can be moved only in the direction

  axial by an elastic plate 16 resembling a washer-

  the or a sliding part 16 a, the reaction force pro-

  pick during pruning which is carried out in the direction

  pendulum 4 re & the Y axis is transmitted to the slide

  tool 2 in the locked part, and no bending constraint is exerted on the element 11; therefore, the rigidity of the coupled part is ensured and, moreover, a precise linearity can be maintained between the pressure

  of the fluid in the chamber 10 and the displacement value of, -

  machine element 1 in the direction of the Y axis.

  We will now proceed to the description of the

  present invention in connection with the embodiments

  shown in Figures 2 and 3.

  The column-shaped element 11 in FIG. 2 is constructed so that the end 14 of the base is

  fixed to the tool slide 2 by a bolt not shown

  felt, and the end 12 to the tool holder support 1 by means of a head element 17 The holding element 15 is

  in one piece with the tool holder support 1, a cy-

  lindrique surrounding the element 11 is formed in the tool holder support 1, and a sleeve 18 is mounted in this hole to constitute the pressure chamber 10, The sleeve 18 is mounted so that the fluid under pressure of the chamber 10 does not act directly on the tool holder support, which consists of a cast part, and this results

  that it forms substantially the same assembly with the device

  fixing pin 15, and its lower end can

  smooth on the base part 14 of the element 11 The base part 13 of the element 11 and the fixing device 15 are linked and can only move in the axial direction of the element 11 by means of the part sliding 16 a, but so as to increase the rigidity of the coupling part, the fixing device 15 and the base part 13 of the element ll are linked by an elastic plate 16 in the form of a washer The inner diametrical part of the plate 16 is placed between the end 14 of the base of the element 11 and the slide-tool holder 2 and is fixed to the side of this slide, and its outer diametrical part is placed between the lower end of the fixing device 1 5 and the holding element 19, and is fixed to the side of the fixing device 15 The reference numbers 20, 21, 22 represent oil supply holes

  pressurized which are practiced in the slide

  tool 2 and element 11, reference numbers 23 and 24

  liquid seal kits, and the re-

  reference 25 a mixed line indicating a workpiece.

  2 Q In the previous structure, when the high pressure actuating oil is supplied to the pressure chamber 10, the pressure exerts a tension stress

  uniform in the axial direction of the element 11, and this results therefrom

  te that the tool holder support 1 moves in a micro-quantity in the upper direction of Figure 2, taking into account the resulting elastic deformation of the element 11 so that the micro-advances in the direction of Y axis can be applied to the tool mounting shaft 7.

  The assembly supplying the chamber 10 with oil pres-

  and the control system are shown in figure

  gure 3; the reference 26 represents a cylinder of the set

  pressure oil supply hose, reference 27

  a diver moving back and forth in the cy-

  lindre 26, reference 28 a one-piece screw with the bolt

  geur 27, the reference 29 a gear engaged with the screw 28, the reference 30 a gear engaged with the gear 29, the reference 31 a DC motor driving 7. the gear 30 and the reference 32 a pipe oil under

  pressure The motor 31 is rotated by a servo

  control which is actuated by the control assembly which will be described later, rotates the gear 29 supported by the chassis (not shown), this gear

  being supported by a bearing 33, and causes the movement-

  ment of back and forth of the non-rotary plunger 27 so that there is a variation in the pressure of the actuating oil to be supplied to the chamber 10, and modifies the value of the displacement of the tool holder support 1 in the direction of the Y axis.

  The value of the movement of the door-or-holder

  til 1 is detected by a differential transformer 34,

  and applied to a differential amplifier 36 by the

  through an isolated amplifier 35, and on the other hand, the instruction data A applied from the numerically controlled device or other instruction device

  (not shown) is applied to the differential amplifier

  tiel 36 via a digital / analog converter 52, and a servo amplifier 53 controls the motor 31 with the differential signal When the output of the differential amplifier 36 is inside

  of a range of permissible fixed values, a corner signal

  cidence B leaves a comparator 37 to be applied to

  instruction device, via a photo-

  coupler 54 and the position of the Y axis of the holder support

  tool 1, i.e. tool 8 is assumed to be set

  at the position defined by the instruction.

  As described above, the tool holder support 1 has its position corrected in the direction of

  the Y axis or is moved, and the machining error due to the

  thermal formation of the part 25 or the machining error due to abrasion of the tool 8 is corrected, and machining with

  an accuracy corresponding to the difference of various di-

  mounting dimensions, such as a keyway or the like, can be obtained by moving the mounting bracket

  tool holder 1 in the direction of the Y axis, but as shown

  uniform tension tension is applied only to element 8, 11 in the construction described above, the precise linear relationship between the pressure of the oil supplied to the chamber 10 and the displacement of the tool holder support 1 is guaranteed, from which it follows that the control of the displacement value can be carried out easily with extreme precision. The previous embodiment is obtained in

  using the coupling mechanism of the present invention

  tion in the form of the Y-axis correction set of the

  io tool holder 1 of lathe W, but the mechanism for

  coupling of the present invention provides great stiffness

  tee of the coupling part and allows to control minu-

  carefully and with great precision, the operation and effect of the relationship between the positions of the

  machine, so that it can be used as an ac-

  coupling for corresponding machine elements including

  rigidity and precision are essential For example-

  ple, the drill B shown in FIG. 4 is such that the column 38 and the base part 39 are coupled by the coupling mechanism 40 of the present invention, and the angle of the column 38 can be adjusted in increments and

  correctly by selectively supplying pressurized oil

  se with the respective coupling mechanisms 40 40 In addition, in turn T of FIG. 5, in the case where the tailstock 41 and its slide 42 are coupled in the horizontal direction by the mechanisms 40 40 of the present

  invention, the part 25 placed between the pin 43 and the connector

  tre-poupée 41 can be moved at minus angles.

  in the horizontal plane so as to execute the cor-

  rectification of the taper of the part or of the cylindrical form

  that and, in addition, in the case where the tool holder support

  44 and the tool slide 45 are coupled by means of the

  mechanisms 40, 40 of the present invention in the ho- sense

  horizontally, the cutting tool 46 can be moved statically-

  lying or dynamically in a back and forth movement of

  so as to correct the difference in dimension of the outside diameter

  of part 25 or the absence of roundness, The reference

  rence 47 of FIG. 4 represents a support plate, to which the column 38 is fixed, and this plate and the base 39 are coupled by the mechanisms 40 40; the reference 48 in FIG. 5 represents the bench, the reference 49 the base and the reference 50 the machine frame in which the spindle drive mechanism is incorporated. Column-shaped element 11 of the mechanism

  coupling of the present invention has a rigidi-

  high tee in the axial direction, and the value of the possible displacement of the coupled machine elements is less than 1 millimeter The control of the displacement value can be carried out with an accuracy of the order of a micron;

  and the pressure of the fluid supplied to the chamber 10 is practical

  set to a high value between 50 and 70 M Pa.

  In this high pressure fluid, as indicated above, the compression properties of the air to be mixed with the fluid

  become an important factor in the deterioration of the pre-

  displacement value control, in particular

  link, dynamic control precision So as to avoid

  ter deterioration of control accuracy by air

  mixed, it is effective to minimize the volume of the cham-

  bre 10 to make it as small as possible, and a man-

  chon 51 is inserted into chamber 10 so as to minimize

  ser the volume of this chamber as represented by the li-

imaginary gene in Figure 2.

  As just described, the mechanism

  coupling of the present invention is capable of re-

  glide the relation between the positions of the elements of machi-

  only mated thoroughly and with extremely high precision, and it is possible to correct the position error

  3 Q between the machine elements with great precision, er-

  position error which is due to various causes, and a large

  rigidity of the coupling part is ensured so that the coupling mechanism of the present invention is extremely useful to serve as a coupling mechanism

  machine elements requiring rigidity and precision.

  The present invention is not limited to the examples

  ples of realization which have just been described, it is on the contrary susceptible of modifications and variants

  which will appear to those skilled in the art.

Claims (3)

  1 Coupled structure of components of a machine tool, which comprises mutually coupled elements, and the machine elements are coupled by a coupling mechanism, characterized in that the coupling mechanism comprises a pressure chamber , a column-shaped element is subjected to a uniform tension stress exerted by the fluid under pressure of the chamber in the form of a uniform tension stress in the axial axis, and a fixing device which consists essentially of a rigid material and attached to the end of the column-shaped element and coupled to   the extreme part of the base of the co-shaped element   feeds so that it can only be moved in the axial direction, the coupling mechanism being in one piece   with machine elements which are mutually coupled-   lie at the end of the base of the column-shaped element and to the fixing device so that the   pressure of the fluid prevailing in the chamber is found trôlée.   2 Structure according to claim 1, character-   in that the one-piece coupling mechanism with the machine elements mutually coupled to the machine tool is coupled with the end part of the base of the column-shaped element and the fixing device so that it cannot be moved only in the axial direction of the column-shaped element by the interposition of a   spring-like elastic plate between the end   me from the base of the columnar element and the fixing fixture,   3 Structure according to claim 1, character-   laughing at the fact that the machine parts to be coupled   mutually plied in the machine tool are the support for   tool holder and tool holder slide.