FR2767726A1 - PRESS FOR FORMING A SHEET OF SHEET - Google Patents

Abstract

The subject of the invention is a press for forming a sheet blank (2), of the type comprising two working elements (3, 4). The press comprises at least one tool (10) for punching the sheet blank (2), at least one member (11) for moving said punching tool and means (15) for controlling said member (11) actuated by one of the elements (3, 4) of the press at the end of the operation of forming this sheet blank (2) by said elements (3, 4) for punching said sheet blank in a portion having undergone deformation in said press.

Description

The subject of the present invention is a press for forming a blank of

  sheet metal, of the type comprising two elements

of work.

  The increasing complexity of the parts produced by forming requires the combination of several operations, such as, for example, punching, sizing, trimming, or falling or lifting the edges of the part, which

  multiplies the number of tools to perform these operations.

  So far, the various operations for

  get the finished part are done in different ma-

  each with a specific tool for the operation

to achieve.

  For example, a press performs the calibration of the part and another press carries out the punching of this

room.

  Therefore, each part must be transferred from one machine to another and positioned in each machine thus increasing the number of parts handling operations, the manufacturing time and of course the cost.

  of each piece and the risk of scattering the ratings.

  The object of the invention is to avoid these inconveniences.

  by proposing a forming press which allows

  successively read several operations on the same piece, in particular the calibration or the falling or lifting of the

  edges and punching the workpiece in these cali-

  brage or falling or lifting of the edges.

  The subject of the invention is a forming press

  of a sheet blank, of the type comprising two working elements

  vail, characterized in that it comprises at least one tool

  for punching the sheet blank, at least one displacement member

  cementing of said punching tool and control means of said displacement member actuated by one of the elements of the press at the end of the operation of forming this sheet blank by said elements to punch said sheet blank in a portion having undergone deformation in said press. According to other characteristics of the invention: - the control means comprise an energy production member actuated by the movement of said

  element of the press, an organ of accumulation and resti-

  tution of energy and a triggering organ of the resti-

  energy consumption at the displacement member of the punching tool at the end of the sheet blank forming operation, - the displacement member is formed by a jack

  actuator whose piston supports the punch tool-

  swimming, - the energy producing organ is formed by

  a drive cylinder whose piston is actuated by the-

  said press element and whose working chamber is connected to the working chamber of the actuating cylinder by

  a fluid line comprising the accumulator member

  tion and restitution of energy and the triggering organ-

  ment, - the organ of accumulation and restitution

  energy is formed by a fluid accumulator under pressure

  sion, - the triggering member is formed by a solenoid valve controlled by a detector of the end position of said press element, - one of the press elements is formed by a fixed matrix carried by a lower frame and the other

  of said elements of the press is formed by a cam tool

  librage carried by means of at least one elastic member by a

  upper frame movable vertically, said tool

  release supporting the movement member of the punching tool and said upper frame actuating the

  power generation and the electric control detector

  valve, - the calibration tool includes an opening for the punching tool to pass through, - one of the elements of the press is formed by a fixed die carried by a lower frame and the other of said elements of the press is formed, on the one hand, by an upper blank holder carried by means of at least one elastic member by an upper frame movable vertically and, on the other hand, by a falling tool of at least one edge of the

  sheet metal blank and integral with the upper frame, said frame

  lower supporting the movement member of the punching tool for punching the sheet blank on the fallen edge and said upper frame actuating the

  power generation and the electric control detector

  valve, - the edge falling tool has a hole for the punching tool to pass through, - one of the elements of the press is formed by a vertically movable lower blank holder supported by at least one member elastic by a fixed lower frame and by a tool for lifting at least one edge of the sheet metal blank and integral with the lower frame and the other of said elements of the press is formed by an upper blank holder carried by means of minus an elastic member by a frame

  vertically movable upper, said upper blank holder

  laughter supporting the movement member of the punching tool

  punching for punching the sheet blank on the raised edge and said upper frame actuating the

  power generation and the electric control detector

  valve, - the upper blank holder has an opening

passage of the punching tool.

  The characteristics and advantages of the invention

  will appear during the description which follows,

  born only by way of example and made with reference to the accompanying drawings, in which: - FIG. 1 is a schematic sectional view

  transverse of a sheet metal blank forming press,

  form of the invention, at the start of work, - Fig.2 is a schematic view on a larger scale of the control means of the punching tool mounted on the forming press, - Fig. 3 is a schematic cross-sectional view of the forming tool closed at the end of work, - FIG. 4 is a schematic cross-sectional view of the forming tool at the start of its ascent, - FIG. 5 is a schematic view of a pre-

  first variant of a forming press according to the invention

  tion, - Fig. 6 is a schematic cross-sectional view of a second variant of a forming press according to the invention, - Figs. 7 and 8 are schematic views in

  cross section showing the different stages of operation

  operation of the press shown in FIG. 6.

  In Fig. 1, there is shown schematically

  a forming press designated as a whole by the re-

  ference 1 and intended in particular to calibrate a sheet blank 2. For this, the sheet blank 2 is first

  stamped on a press and the forming press 1 is intended

  born to calibrate this sheet metal blank 2 and in particular to bring the

  curved portions for connection to the desired radius of curvature

re.

  This press 1 has two working elements

  vail, respectively 3 and 4, between which is positioned

the sheet blank 2.

  In the exemplary embodiment shown in FIG. 1, the working element 3 is formed by a matrix

  fixed 6 carried by a lower frame 5.

  The matrix 6 has on its upper face a

  shape 6a corresponding to the shape of the sheet blank 2 to be obtained

  nir. The working element 4 is formed by a calibration tool 7 carried by means of an elastic member 7a by a

  upper frame 8 vertically movable.

  The calibration tool 7 has on its side

  lower an imprint 7b whose shape corresponds to the

  shape of the sheet blank 2 to be obtained.

  The lower face of the upper frame 8 determines with the upper face of the calibration tool 7 a stroke

security 'h ".

  The press 1 also includes at least one punching tool 10 intended to make a hole 2a or a mark on the sheet blank 2 after the calibration of said blank.

  sheet 2 by the calibration tool 7 and the matrix 6.

  The press 1 also includes a member 11 for

  placement of the punching tool 10 and of the means 15 for controlling this displacement member 11 actuated at the end

  of the calibration operation of this sheet blank 2.

  In the embodiment shown in

  Fig. 1, the calibration tool 7 supports the member 11 for

  placement of the punching tool 10 and the means 15 for controlling the displacement member 11 are actuated by the

  upper frame 8, as will be seen later.

  Referring now to FIG. 2, let's

  describe the means 15 for controlling the displacement member;

  11 actuated by the upper frame 8.

  The control means 15 comprise an energy production member 16 actuated by the movement of the

  upper frame 8, an organ 17 for accumulation and restitution

  tion of energy and an organ 18 for triggering the resti-

  energy consumption at the tool movement member 11

punching 10.

  The member 11 for moving the punching tool

  10 is formed by an actuating cylinder comprising a body 12 inside which is slidably mounted a

  piston 13 whose free end supports the punching tool

tonnage 10.

  The piston 13 delimits inside the body 12, a chamber 14a filled with a gas, such as for example

  nitrogen, and a working chamber 14b into which

  che a first end of a supply line 19

  a pressurized fluid, such as oil.

  The energy producing member 16 is formed

  by an actuating cylinder comprising a body 16a with lin-

  inside of which a piston 16b is slidably mounted, the ex-

  free end is intended to come into contact with the frame

higher 8.

  The piston 16b delimits, inside the body 16a of the drive cylinder 16, a working chamber 16c

  into which the second end of the pipe opens

  tion 19 connected to the working chamber 14b of the actuator

operation 11.

  The energy accumulation and restitution member 17 is formed by an accumulator which includes a

  body 17a inside which a slide is mounted slidingly

your 17b.

  This piston 17b delimits inside the body

  17a, a first chamber 17c filled with gas as for example-

  full of nitrogen, and a second chamber 17d which communicates

with line 19.

  The triggering member 18 is formed by a solenoid valve whose coil is connected to a detector 20

  the end position of the upper frame 8.

  In the exemplary embodiment shown in FIG. 1, the member 11 for moving the punching tool

  is carried by the calibration tool 7 which includes an ori-

  file 21 arranged in the axis of the punching tool 10 and at a determined location corresponding to the position of the hole

  2a to be made in the sheet blank 2.

  Similarly, the die 6 has an orifice 22 so as to allow the punching tool 10 to pass through

the sheet blank 2.

  Referring now to Figs. 1 to 4, we

  will describe the operation of the forming press 1.

  First of all, the preformed sheet blank 2 is

  dried on the die 6 and the upper frame 8 is in top dead center and the calibration tool 7 is moved away from the die 6,

as shown in Fig. 1.

  In this position, the solenoid valve 18 is closed.

  mé, the drive cylinder 16 is open, the accumulator

  17 is at the initial loading pressure and the oil con-

  held in the working chamber 16c of said drive cylinder

  ment 16 is not compressed, as shown in FIG. 2.

  In addition, the actuating cylinder 11 is in posi-

  tion rest and the punching tool 10 is retracted.

  Then, the upper frame 8 descends progressively-

  and drives the calibration tool 7 through

  diary of the elastic member 7a in such a way that this or

  Calibration wire 7 comes into contact with the sheet blank 2.

  During the descent of the upper frame 8, the latter comes into contact with the upper face of the calibration tool 7 after having compressed the elastic member 7a and

  the whole goes down to carry out the work.

  On the other hand, the upper frame 8 comes into con-

  tact with the piston 16b of the drive cylinder 16 and this piston 16b gradually descends so as to compress

  the oil contained in the working chamber 16c and trans-

  squeeze this oil under pressure in chamber 16d of the ac-

accumulator 17.

  The piston 17b moves and compresses the gas

  held in chamber 16c of accumulator 17.

  When lowering the upper frame 8, the elect

  valve 18 is still closed and the punching tool 10

  is still in the retracted position.

  When the upper frame 8 comes to bottom dead center, that is to say at the end of the calibration of the sheet blank 2 for the calibration tool 7, this upper frame 8 actuates the

  detector 20 which has the effect of opening the solenoid valve 18.

  The drive cylinder 16 is always included.

me.

  As soon as the solenoid valve 18 opens, the accumulator

  lator 17 discharges the oil in the line 19 under the effect of the compression of the gas in the chamber 17c of this

accumulator 17.

  The pressurized oil enters the working chamber 14b of the actuating cylinder 11 which has the effect

  move the piston 13 and the punching tool 10.

  As soon as the calibration tool 7 reaches the point

  dead low to calibrate the sheet blank 2, the punching tool

  sinking 10 penetrates into the orifice 21 formed in this calibration tool 7 by punching the sheet blank 2 and the upper frame 8 rises while the calibration tool 7 remains pressed against the elastic member 7a against the

  sheet blank 2 and die 6 so as to allow the

  punching wire 10 to be able to punch the sheet blank 2 in a portion having undergone deformation in said forming press 1, as shown in FIG. 4. As shown in this figure, during

  punching the sheet blank 2, the upper frame 8

  begins to go up a height corresponding to the stroke of the elastic member 7a while the calibration tool 7

  rests on said sheet blank 2 so as to hold it

  hold while raising the punching tool 10.

  The calibration tool 7 rises driven by the upper frame 8 and, due to the backload pressure in the chamber 14a of the actuating cylinder 11, the

  punching 10 returns to its initial position.

  The drive cylinder 16 also resumes its

  initial position and the accumulator 17 is recharged.

  Then, the solenoid valve 18 is closed and the

  seems control means is ready for a new punching. Thanks to the time delay between the calibration operation and the punching operation, this punching is carried out at the end of the calibration of the sheet blank, that is to say after the creep of the material constituting this sheet blank which guarantees the accuracy of the punching position

on said sheet blank.

  In addition, thanks to the safety stroke "h" between

  the calibration tool 7 and the upper frame 8, the punch-

  swimming of the sheet blank 2 is carried out during operation

  of the press without penalizing its production rate while guaranteeing the accuracy of the punching, while avoiding deformation of this sheet blank 2 during removal

of the punching tool 10.

  According to a variant shown in FIG. 5, the punching of the sheet blank 2 can be carried out after the fall of at least one edge of this sheet blank 2. For this and as shown in this figure, the forming press 1 comprises, on the one hand, a working element 3 formed by a fixed matrix 30 carried by a lower frame 31 and, on the other hand, a working element 4 formed by an upper blank holder 40 carried by means of at least one elastic member 40a by a frame upper 41 movable vertically and by a falling tool 42 of at least one

  edge of the sheet blank 2 and secured to the upper frame 41.

  In this case, the punching tool 10 and its actuating cylinder 11 are arranged on the lower frame

  31 and the axis of said punching tool 10 extends perpendicularly

  cularily to the vertical axis of the matrix 30.

  The means 15 for controlling the displacement member

  cement 11 of the punching tool 10 are identical to those previously described and the upper frame 41 actuates the member 16 for producing energy and the detector 20 for

solenoid valve control.

  The tool 42 for falling off the edge of the sheet blank 2 has an orifice 23 for the passage of the punching tool 10 of dimensions greater than the section of the

  punching 10 and the die 30 also includes an ori-

  punch 22 of the punching tool 10 and located

in the axis of the orifice 23.

  The underside of the upper frame 41 is housed with the upper face of the upper blank holder 40 a

safety race.

  As soon as the upper frame 41 comes to bottom dead center and the tool 42 has fallen off the edge of the sheet blank 2, the punching tool 10 is actuated

  so as to punch the sheet metal blank 2.

  Then, the upper frame 41 progressively rises

  vement driving in its movement the falling tool 42

from the edge of the sheet blank 2.

  The upper blank clamp 40 remains in abutment on the sheet blank 2 and on the matrix 30 by virtue of the elastic member 40a so as to maintain the sheet blank 2 during

its punching.

  Due to the dimensions of the orifice 23, the tool

  42 falling from the edge of the sheet blank 2 can rise pro-

  gressively without hampering the movement of the punch tool-

swim 10.

  According to another variant represented on the

  Figs. 6 to 8, the punching of the sheet blank 2 can be ef-

  made after lifting at least one edge of this blank

sheet 2.

  The working element 3 of the press 1 is formed,

  on the one hand, by a vertically displaceable lower blank holder 50

  wedging and supported by means of at least one elastic member a by a fixed lower frame 51 and, on the other hand, by a tool 52 for lifting at least one edge of the sheet blank 2 and

secured to the lower frame 51.

  The working element 4 of the press 1 is formed, on the one hand, by an upper blank holder 60 carried by means of at least one elastic member 60a by an upper frame 61

vertically movable.

  In the embodiment shown in Figs. 6 to 8, the working element 4 also includes a

  tool 62 for dropping at least one edge of the sheet blank 2.

  This tool 62 is integral with the upper frame 61.

  As shown in FIG. 6, the upper blank holder 60 supports the member 11 for moving the punching tool 10 to punch the sheet blank 2 on the raised edge and the upper frame 61 actuates the member 16 for producing energy and detector 20 of

solenoid valve control 18.

  In this case, the upper blank holder 60 comprises an orifice 53 for the passage of the punching tool 10 and the tool 52 for lifting the edge of the sheet blank 2 comprises

  also a hole 54 for penetrating the punching tool.

  10 and located in the axis of the orifice 53 when the

  work elements 3 and 4 are closed.

  The elastic member 50a is calibrated at a force greater than the taring force of the elastic member 60a so that the elastic member 50a does not start to compress until the elastic member 60a has arrived. limit switch.

  This press 1 operates as follows:

  boasts. First of all the upper frame 61 as well as the upper blank holder 60 are at top dead center and separated

of the lower blank holder 50.

  The sheet blank 2 is positioned on the clamp

  lower blank 50, as shown in FIG. 6.

  The upper frame 61 descends progressively, driving in this movement the upper blank holder 60 by

  through the elastic member 60a which has the ef-

  fet to pinch the sheet blank 2 between the lower blank holder

  laughing 50 and the upper blank holder 60, as shown in

Fig. 7.

  The upper frame 61 continues to descend which has the effect of compressing the elastic member 60a and

  drop the edge of the sheet blank 2 by means of

tool diary 62.

* Then, the upper frame 61 and the blank holder

  upper 60 continue to descend resulting in compression

  sion of the elastic member 50a and the descent of the blank

  sheet 2 so that the free edge of this sheet blank 2 in

be in contact with the tool 52.

  This tool 52 being fixed, the edge of the sheet blank 2 gradually folds upwards and is pinched between the tool 52 and the underside of the upper blank holder 60 which comprises in front of said tool 52 an inclined face, as

shown in Fig. 8.

  As soon as the upper frame 61 reaches the point

  dead low, the means 15 for controlling the displacement member

  ment 11 of the punching tool 10 are actuated and this punching tool 10 penetrates into the orifice 53 formed in the upper blank holder 60 and performs the punching of the

  sheet blank 2 and allowing stripping.

  When raising the upper frame 61, the

  elastic gane 60a gradually relaxes and maintains the upper blank holder 60 against the sheet blank 2 which does not disturb the operation of the punching tool 10 and makes it possible to maintain the speed of the press 1 while carrying out the punching of the sheet blank 2 and the lifting of the

edge of this sheet blank 2.

  The control means 15 can be actuated if-

  several cylinders 11 simultaneously which each ensure the

  placement of a punching tool 10 so as to produce

  simultaneously several punchings on the sheet blank 2.

  The press according to the invention makes it possible to be able to

  successively carry out at least two different operations

  such as a calibration or tomation operation

  bage and / or lifting of an edge of a sheet blank and a punching operation in a portion of this sheet blank having undergone deformation in said press which ensures precise dimensions and reduces the number of operations of the

  parts, manufacturing time and cost of each part.

Claims (12)

  1. Press for forming a sheet blank (2), of the type comprising two working elements (3,4), characterized in that it comprises at least one tool (10) for punching the sheet blank (2 ), at least one movement member (1)   said punching tool (10) and means (15) for   mand of said displacement member (11) actuated by one of the elements (3,4) of the press at the end of the forming operation of this sheet blank (2) by said elements (3, 4) for punching said sheet blank (2) in a portion   having undergone deformation in said press.   2. Forming press according to claim 1,   characterized in that the control means (15) comprise   nent an organ (16) of energy production actuated by the displacement of said element (3, 4) of the press, a member (17) of accumulation and restitution of energy and a member (18) for triggering the energy restitution to the member (11) for moving the punching tool (10) at the end   of the sheet blank forming operation (2).   3. Forming press according to claims 1   and 2, characterized in that the displacement member is formed by an actuating cylinder (11), the piston (13) of which   supports the punching tool (10).   4. Forming press according to any one of   previous claims, characterized in that the member   of energy production is formed by an actuator (16)   drag whose piston (16b) is actuated by said element   press (3, 4) and whose working chamber (16c)   is connected to the working chamber (14b) of the actuator (11)   operation by a fluid line (19) comprising the member (17) of energy accumulation and restitution and the trigger member (18).   5. Forming press according to claim 2 or   4, characterized in that the accumulator and res-   energy titution is formed by an accumulator (17) of fluid under pressure.   6.Forming press according to claim 2 or   4, characterized in that the triggering member is formed   mé by a solenoid valve (18) controlled by a detector (20) of the end position of said element (3, 4) of the press. 7. Forming press according to any one of   previous claims, characterized in that one (3)   elements of the press is formed by a fixed die (6) carried by a lower frame (5) and the other (4) of said elements of the press is formed by a calibration tool (7) carried by means of at least one elastic member (7a) by an upper frame (8) movable vertically, said calibration tool (7) supporting the member (11) for moving   the punching tool (10) and said upper frame (8) ac-   operating the energy producing member (16) and detecting it   solenoid valve (18) control tor (20).   8. Forming press according to claim 7, characterized in that the calibration tool (7) comprises a   orifice (21) for passage of the punching tool (10).   9. Forming press according to any one of   claims 1 to 6, characterized in that one (3) of   elements of the press is formed by a fixed die (30) carried by a lower frame (31) and the other (4) of said   elements of the press is formed, on the one hand, by a clamp   upper blank (40) carried by means of at least one member   elastic (40a) by a movable upper frame (41) ver-   tically and, on the other hand, by a tool (42) for dropping at least one edge of the sheet blank (2) and secured to the frame   upper (41), said lower frame (31) supporting the or-   gane (11) for moving the punching tool (10) for   punch the sheet metal blank (2) on the tom-   be and said upper frame (41) actuating the member (16) for producing energy and the detector (20) for controlling the solenoid valve (18).   10. Forming press according to claim 9,   characterized in that the tool (42) for falling off the edge comprises   carries an orifice (23) for passage of the punch tool (10)   swim. 11. Forming press according to any one of   claims 1 to 6, characterized in that one (3) of   elements of the press is formed by a lower blank clamp (50) movable vertically and supported by means of at least one elastic member (50a) by a lower frame (51) fixed and by a tool (52) for lifting at least one edge of the sheet blank (2) and integral with said lower frame (51) and the other (4) of said press elements is formed by a   upper blank holder (60) carried by means of at least one gold-   elastic gane (60a) by an upper frame (61) movable vertically, said upper blank holder (61) supporting the member (11) for moving the punching tool (10) to punch the sheet metal blank ( 2) on the raised edge and said upper frame (61) actuating the member (16) for producing energy and the detector (20) for controlling the solenoid valve (18).   12. Forming press according to claim 11, characterized in that the upper blank holder (60) comprises   an orifice (63) for the passage of the punching tool (10).