FR2843320A1 - Device for automatic preparation of metallographic samples comprises polishing post next to vertical magazine supporting polishing plates, pre-polishing post and cleaning post, sample door enabling transfer of plates between posts - Google Patents

Abstract

The metallographic sample preparation device comprises a polishing post (8) located next to a vertical magazine (9) supporting polishing plates. Gripping and transport means (10) enable the plate to be transferred between the magazine and the polishing post. There is a pre-polishing post (6) and a cleaning post (7) located between the polishing and pre-polishing posts. A samples door (11) enables the transfer of the samples between the different posts by a rotational movement around a first rotational axis (s8). Control means engage the gripping means for transferring the plates between the magazine and the polishing post during which the samples door is located above the cleaning post.

Description

Automatic metallographic sample preparation device.

  Technical Field of the Invention The invention relates to a device for preparing metallographic samples comprising a polishing station comprising a tray support, said polishing station being adjacent to a vertical magazine comprising several horizontal shelves, each supporting a tray 10 intended to be placed on the tray support, the device also comprising a sample cleaning station, means for gripping and transporting a tray between the store and the polishing station, a sample holder, intended for polishing and transferring the samples between the polishing and cleaning stations by a rotational movement around a first axis of rotation, and means for controlling the sample holder and

means of transport of the plateau.

   State of the art The document US5800254 describes an automatic machine for preparing metallographic samples, comprising polishing and cleaning stations, a set of shelves supporting several abrasive plates and a transfer mechanism. The transfer mechanism makes it possible to select one of the plates, bring it to the polishing station then put it back in its place on all of the shelves and select a second. The device also includes a sample support head moving between the polishing and cleaning stations. The device does not, however, allow

  the entire sample preparation.

  OBJECT OF THE INVENTION The object of the invention is to provide an automatic metallographic sample preparation device, compact and making it possible to carry out all the steps of preparing samples. According to the invention, this object is achieved by the fact that the cleaning station is arranged between the polishing station and a prepolishing station, so that the sample holder can transfer the samples between the polishing station, the cleaning station and the pre-polishing station, - the means for gripping and transporting the tray comprise a gripper, intended to grip the tray by its upper part and secured to a gripper arm animated by a movement of vertical translation and a rotational movement about a second axis of rotation, so as to move the plate between a store shelf and the polishing station, - the control means (15) cooperate with the gripping means and transport (15), to transfer trays (19) between the magazine (9) 20 and the polishing station (8), while the sample holder (11) is

  arranged above the cleaning station (7).

  According to a development of the invention, the plate support of the polishing station is driven in a rotational movement relative to a third axis of rotation, the pre-polishing station comprising a support of the pre-polishing plate animated with a rotational movement relative to a fourth axis of rotation. According to a preferred embodiment, the axis of symmetry of the magazine and the third and fourth axes of rotation are arranged in the same first

vertical plane.

  According to another characteristic of the invention, the cleaning station has an axis of symmetry, forming, with the first axis of rotation of the door

  samples, a second vertical plane perpendicular to the first vertical plane.

Brief description of the drawings

  Other advantages and characteristics will emerge more clearly from the description which follows of particular embodiments of the invention given by way of nonlimiting examples and represented in the appended drawings,

  in which: FIG. 1 is a schematic representation, front view, of a device for

  preparation of samples according to the invention.

  FIG. 2 is a top view of the magazine and of the stations of the device according to FIG. 1.

  Figure 3 is a partial sectional view of a polishing station of a device

according to the invention.

  Figure 4 shows a dispenser of abrasives and diluent of a device

according to the invention.

  FIG. 5 is a front view of means for gripping and transporting a

  device tray according to figure 2.

  FIG. 6 is a front view, in partial section, of a sample holder of the

device according to figure 2.

  FIG. 7 represents, in the form of a block diagram, control means

of a device according to the invention.

  FIG. 8 represents means of controlling a device according to the invention.

  Description of particular embodiments.

  As shown in FIGS. 1 and 2, the device 1 for preparing samples intended to undergo a metallographic examination, comprises a parallelepipedic frame 2. A first parallelepipedic compartment 3, constituted by four lateral faces and two upper 4 and lower 5 walls, is disposed inside the chassis 2. A pre-polishing station 6, a cleaning station 7, a polishing station 8 and a vertical magazine 9, intended to support polishing plates, are mounted inside the first compartment 3, on the bottom wall 5 (FIG. 2). The first compartment 3

  also comprises gripping and transport means 10 of the plates between the magazine 9 and the polishing station 8, as well as a sample holder 11.

  The gripping and transport means 10 are arranged between the magazine 9

and the polishing station 8.

  A first lateral face 12 of the first compartment 3 is constituted by panes 13, allowing an operator to access the interior of the first compartment 3 and to follow, through the panes, the progress of the various operations for preparing the samples. A second compartment 14, 25 intended to receive control means 15, and a third storage compartment 16 are arranged one above the other, next to the first compartment 3. The control means 15, as well as the gripping and transport means 10 and the sample holder 1 1 make it possible to produce

  an automatic sample preparation device.

  The magazine 9 for polishing plates is arranged against a second lateral face 17 of the first compartment 3, perpendicular to the first lateral face 12 (FIG. 2). It comprises an axis of symmetry sl 1 and several horizontal shelves 18, the number of shelves preferably being between five 5 and ten. Each shelf 18 is intended to support a polishing plate 19 in the form of a disc, making it possible to polish the samples on the polishing station. Each plate 19 has a first circular smooth face (or surface) and a second circular abrasive face (or surface), of a predetermined particle size and different for each plate 19. The plates 10 preferably have a diameter of 300 mm and are arranged on the shelves of the magazine, so that the first smooth face of each tray is placed on the shelf and the second abrasive face is free. The plates 19 can be arranged in the magazine, depending on the particle size of their abrasive surface. For example, they can be arranged from bottom to top by increasing particle size. The magazine 9 can include any type of known centering system, so as to correctly replace the trays on the shelves. The polishing station 8 is arranged next to the magazine 9 and is constituted by a tank 20 (FIG. 3), mounted on the bottom wall 5 of the first compartment

  3, the tank 20 being preferably made of stainless steel and easily removable for cleaning. The bottom 21 of the tank 20 has an opening 22 into which is introduced a motor shaft 23 having an axis of rotation sl.

  A circular plate support 24 (FIG. 2) is mounted on the motor shaft, 25 perpendicular to the axis of rotation sl, so as to be rotated relative to the axis of rotation sl , during the polishing operation. The plate support 24 is intended to receive and support one of the polishing plates 19. The polishing station 8 also includes

  means for fixing a plate 19, of any known type.

  In FIG. 2, the polishing station 8 also includes a supply arm 25 for abrasives and liquid diluents, retractable along an axis of rotation s2 so as to move it from a first folded position to a second position disposing of it above the tray support 24 supporting a tray 5 19. The second position of the supply arm allows the tray 19 used during

  the polishing operation, to always be wet with the liquid abrasive. The bottom 21 of the tank 20 is preferably inclined (FIG. 3) and has an outlet orifice 26, so as to favor the flow of the liquid abrasive to a container of any type, which is preferably placed under the polishing station 8.

  The supply arm 25 is preferably connected to a plurality of pumps, each pump being connected to a reservoir 27 (or a bottle) comprising an abrasive or a liquid diluent (FIG. 4). The supply arm 25 may comprise a plurality of injection nozzles, each connected to a pump or else

  have a single injection nozzle, connected to all of the pumps. The reservoirs 27 and the pumps are preferably arranged in a tank 28 itself arranged in the third storage compartment 16 of the chassis 2.

  The supply of the abrasive supply arm is controlled by the control means 15, which in particular determines the abrasive adapted to the plate 19 disposed

on the tray support.

  The gripping and transport means 10 of the plates 19 make it possible to automatically select and transfer a first plate 19, from the shelf 18, on which it is placed, to the plate support 24 of the polishing station 8, on which the first plate 19 must be placed to perform a first polishing operation (Figures 2 and 5). Following the first polishing operation, the gripping and transport means transfer the first tray 19 placed on the tray support 24 to the shelf of the magazine 9 intended to support it. They then choose and transport a second plate to the plate support 24 for a second polishing operation. The particle size of the abrasive surface of the second plate is usually smaller than that of the first plate. Several polishing operations can take place successively, using a plate for each operation.

smaller grain size.

  The gripping and transport means 10 comprise a gripper, pneumatic, flat, and preferably consisting of three rods 29, 10 the rods being arranged regularly around an axis of symmetry s3 (Figure 2). The free end of each rod 29 comprises a hook 30 making it possible to hold one of the plates 19 by its periphery, the clamp then gripping the plate by its upper part, that is to say by its second abrasive face. In Figure 5, the clamp formed by the three rods 29 is secured to a gripper arm 31, which is driven in a vertical translational movement. The gripper arm 31 can move vertically between a first low position located substantially at the height of the tray support 24 and a second high position located above the highest shelf 18 of the store 9. The most bottom of magazine 9 is preferably located at a height greater than or equal to the height of the polishing station 8 and

  in particular that of the tray support 24.

  The gripper arm 31 is also driven in a rotational movement, along an axis of rotation s4, so as to move between a first position of rotation and a second position of rotation. The first rotational position is located at the store 9, between two shelves 18, so as to allow a tray 19 to be placed (or lifted) on (from) a shelf 18, while the second rotational position is located above of the polishing station 8, so as to allow the laying (or lifting) of a plate 19 on the (of) the plate support 24. When the gripper arm 31 is disposed in the first position of rotation, the axis of symmetry s3 of the concise gripper, of

  preferably, with the axis of symmetry sl 1 of the magazine 9 (Figures 1 and 2).

  The gripper arm is integral with a first guide column 32, it

  even secured to the chassis 2 by a vertical support 33. The translation of the gripper arm is ensured by a motor 34 arranged in the upper part of the guide column, above the gripper arm and by a ball screw 35.

  The rotation of the gripper arm is ensured by the rotation of the first guide column 32 on itself. Two lower and upper pivots 36 and 37 integral with the vertical support 33 serve to support the first vertical guide column 32 and allow it to rotate around the axis of rotation s4 which is also the axis of symmetry of the first column of guide 32. The rotation of the first guide column 32 can be driven by any type of means known per se. In Figure 5, the lower end of the first

  guide column 32 comprises a drive pulley 38 which can be connected to a motor by a drive belt. The movements of translation and rotation of the means for gripping and transporting the plates, therefore the motors generating these movements, are controlled by the control means 15.

  The operating mode of the gripping and transport means 10 for trays makes it possible to produce an automatic and compact device. In fact, the transfer of trays being carried out according to vertical translational and rotational movements, the gripping and transport means 10 can

  be brought closer to store 9 and polishing station 8.

  In FIG. 2, the pre-polishing station 6, also called dressing station or grinding station, is arranged in the first compartment 3, against a third lateral face 39, opposite to the second lateral face 17 of the first compartment 3 and perpendicular to the first lateral face 12. The pre-polishing operation makes it possible to flatten the samples to be polished. The pre-polishing station 6 is similar to the polishing station 8, comprising a tank in which is disposed a pre-polishing plate support 40 whose rotation around an axis of rotation s5 is ensured by a motor shaft . The grinding station 6 is preferably arranged so that the three axes sl 1, sl and s5, which are respectively the axis of symmetry of the magazine 9, the axis of rotation of the plate support 24 of the polishing station 8 and the axis of rotation of the support of the pre-polishing plate 40 of the pre-polishing station 6 are preferably arranged in the same first vertical plane. The first vertical plane perpendicularly cuts the bottom wall 5 of the first compartment 3 according to a

right s6 (figure 2).

  The pre-polishing station 6 can also be equipped with a lapidary wheel

  280 mm or a magnetic system allowing the use of diamond or composite plates. It may include a straightening arm 41, used in combination with a lap stone. After each use of the grinding wheel, the diamond coating is done automatically. The tank is preferably covered by a cover, so as to avoid the projection of liquid abrasive.

  The cleaning station 7 preferably comprises a cylindrical cleaning tank 42 having an axis of symmetry s7, two detergent pressure inlets and a water inlet for rinsing the samples. It is arranged between the polishing station 8 and the pre-polishing station 6, so that the axis of symmetry s7 is parallel to the first vertical plane formed by the axes sl 1, sl

  and s5 and offset towards the first lateral face 12.

  A sample holder 11 is disposed between the pre-polishing station 3 and the polishing station 8. It is intended to support and polish several samples, to move from one station to another by a rotational movement around an axis of rotation s8. The rotational movement makes it possible to place the samples 5 on the plate 19 of the polishing station 8, or in the cleaning tank 42 of the cleaning station 7 or on the plate of the pre-polishing station 6, so as to polish them, to clean or grind them according to the operation to be carried out. The axis of rotation s8 and the axis of symmetry s7 of the cleaning tank preferably forms a second vertical plane, preferably perpendicular to the first vertical plane. 10 The second vertical plane intersects the bottom wall 5 of the first compartment 3

along a straight line s9 (Figure 2).

  As shown in FIG. 6, the sample holder 11 comprises a vertical support element 43 and integral with the first compartment 3 of the device, a second vertical guide column 44 and mounted on the support element 43.

  The sample holder 11 also includes a support box 45 mounted on the guide column and a polishing head 46 integral with the support box 45, so that the assembly formed by the polishing head 46 and the support box 45 can move vertically. The polishing head 46 is extended into a plate 47 on which samples to be prepared are mounted, preferably six. The samples can be coated or uncoated, and have

  generally a diameter between 20 and 50mm.

  The second guide column 44 can be rotated around its axis of symmetry which is the axis of rotation s8 of the sample holder 11, so as to move the samples supported by the plate 47 of a station to another by a rotational movement of the second guide column 44 around the axis of rotation s8. The rotational movement can be achieved by any type of known means. In FIG. 6, the rotation of the second guide column 44 is ensured by a rotation motor 51 of the guide column, disposed at the lower end of the second column of

guide 44.

  The polishing head 46 is intended to move, by a vertical translational movement of the support housing 45, the samples between a lowered height and a raised height. The lowered height is equivalent to placing the samples on a plate 19 of the polishing station 8 or on a plate of the pre-polishing station 6, while the raised position corresponds to a predetermined height which does not hinder the transfer of samples from a post to another. The translational movement can be achieved by any type of known means. In Figure 6, a hydraulic cylinder 48 is mounted on the upper part of the second guide column 44, so as to ensure the translation

  support case 45.

  The polishing head 46 is also driven in a rotational movement around its axis of symmetry s10, so that the samples are driven in a rotational movement, preferably opposite to that of the plate of the polishing station 8 or from the pre-polishing station 6, when the samples 20 are placed on the polishing plate to be polished. The rotational movement of the polishing head 46 and of the samples makes the polishing or pre-polishing operation more efficient, when the samples are in contact with a plate 19 of the polishing station 8 or a plate of the pre-polishing station. polishing 6. In FIG. 6, the rotation of the polishing head is ensured by a motor for rotation of the polishing head 49 disposed inside the support housing 45, transmission means of known type connecting the shaft of the polishing head rotation motor 49 to the polishing head 46. The speed of rotation of the polishing head is preferably variable and

  between 20 revolutions per minute and 100 revolutions per minute.

  The plate 47 is integral with the polishing head 46, thanks to a central cylinder 50 disposed between the free end of the polishing head 46 and the plate 47. The central cylinder exerts a central pressure on the plate and on the samples. The stage preferably has a diameter of approximately 160mm, making it possible to polish 3 or 5 samples from 20mm to 50mm in diameter. Each sample can also receive an intermediate pressure by means of jacks 51 arranged above each sample, between the polishing head 46 and the plate 47,

  this allows to polish from 1 to 6 samples from 20mm to 50mm in diameter.

  The translational and rotational movements of the sample holder 11 and of the gripping and transport means 10 of the trays 19 are controlled automatically by the control means 15. The control means 15 instruct the sample holder to be placed above of the cleaning station 7 or of carrying out a cleaning operation, during the transfer 15 of the plates 19 between the magazine 9 and the plate support 24 of the polishing station 8. They also make it possible to switch from a first pressure mode exerting a central pressure by means of the central jack 50 on the plate 47 to a second pressure mode exerting a pressure on each sample by means of the jacks 51. As shown in FIG. 7, the control means 15 comprise a unit 52 for data processing, comprising an input terminal connected to a keyboard 53 and 4 output terminals. The keyboard 53 allows an operator to supply the processing unit 52 with the parameters of the sample preparation method. Three of the output terminals respectively control the gripping and transport means 10 of trays, the sample holder 11 and the pumps connected to the reservoirs or bottles 27 in liquid abrasives of the polishing station 8. The fourth output terminal is connected to a screen 54 which allows you to view all the parameters and the progress of the sample preparation method. The keyboard 53 and the screen 54 are preferably arranged in the second compartment 14, while the processing unit 52 is placed on a fourth lateral face 55 of the

  first compartment 3 (FIG. 2), opposite the first lateral face 12.

  From a limited number of control parameters, the control means make it possible to carry out all of the operations for preparing samples, that is to say pre-polishing, polishing according to different types of particle size and cleaning of samples. The control parameters are, for example, the nature of the samples to be prepared, the choice between the first and second pressure modes to be applied to the plate 47. The control means 15 comprise methods for preparing samples predetermined according to command parameters. Thus for a given material, the control means determine the pre-polishing operations to be carried out, the number of polishing operations required, the type of plates 19 to be used, the duration of each polishing step, the type

liquid abrasive to use ...

  The control means 15 also make it possible to control the wear of the plates 19 and the quantity of abrasives or liquid diluents remaining in the

  tanks or flasks 27 (Figure 8). The control parameters are, for example, for the wear of the plates, the position of the plates 19, their lifetime and the date on which the abrasive surface of the plates 19 was changed.

  The processing unit calculating the time of use of this tray since this date, alerts the user by a message on the screen 54, of the wear of the tray when the latter reaches a higher usage time. at a predetermined time. For the capacity of the bottles 27, the processing unit calculates, as the preparation operations take place, the quantity of liquid abrasive consumed, as a function of the quantity introduced into the bottle 27 and sends a

  alert message on the screen when a bottle is almost empty.

  According to a particular embodiment, the steps for producing a preparation device according to the invention are as follows: - An operator places the samples to be polished on the stage 47 and enters the control parameters on the keyboard 53, - L the processing unit 52 then determines the method to be used and orders the sample holder 11 to be placed above the pre-polishing station 6, - Depending on the nature of the samples to be polished, a first pre-polishing step can take place , - The processing unit 52 then instructs the sample holder to place the samples in the tank of the cleaning station 7 if a cleaning operation is programmed, otherwise the sample holder is positioned above the tank 15 of the cleaning station 7, - As soon as the sample holder is placed at the cleaning station 7, the processing unit 52 commands the gripper arm 31 to take a first plate 19 from a predetermined shelf 18 e by the processing unit 52 and transfer it from the magazine 9 to the tray support 24 of the polishing station 8, - The processing unit 52 then moves the sample holder from the cleaning station 7 to the polishing station 8, - A first polishing operation can thus take place for a predetermined duration, - At the end of the first polishing operation, the sample holder is replaced above the cleaning station 7, while the gripping and transport means replaces the first plate 19 with a second plate 19, for a second polishing operation, - When all the polishing operations are finished, the sample holder is placed above the cleaning station 7 to clean and dry the samples and the plate supporting them. During the cleaning phase, the polishing head 46 rotates slowly while for spinning,

  the speed of the polishing head 46 accelerates.

  The advantage of the sample preparation device is that it automatically performs all of the sample preparation operations before their examination, which makes it possible to carry out preparations continuously, 24

  24 hours a day, for example or repetitive operations.

Claims (9)

claims   1. Device for preparing metallographic samples comprising a polishing station (8) comprising a plate support (24), said polishing station (8) being adjacent to a vertical magazine (9) comprising an axis of symmetry (sl 1) and several horizontal shelves (18), each supporting a tray (19) intended to be placed on the tray support (24), the device also comprising a cleaning station (7) for the samples, gripping and transport (10) of a tray (19) between the magazine (9) and the polishing station (8), a sample holder (11), intended to polish and transfer the samples between the polishing stations (8) and cleaning (7) by a rotational movement around a first axis of rotation (s8), and control means (15) of the sample holder (11) and gripping and transport means (10) of the tray (19), device characterized in that: - the cleaning station (7) is arranged in be the polishing station (8) and a pre-polishing station (6), so that the sample holder (11) can transfer the samples between the polishing station (8), the cleaning station (7) and the pre-polishing station (6), - the gripping and transport means (10) of the plate (19) comprise a gripper, intended to grip the plate (19) by its upper part and integral with a gripper arm (31) animated by a vertical translational movement and a rotational movement around a second axis of rotation (s4), so as to move the plate (19) between a shelf (18) of the magazine (9) and the polishing station (8), - the control means (15) cooperate with the gripping means and   transport (15), to transfer trays (19) between the magazine (9) and the polishing station (8), while the sample holder (11) is arranged above the cleaning station (7).   2. Device according to claim 1, characterized in that the plate support (24) of the polishing station (8) is rotated by   relative to a third axis of rotation (sl).   3. Device according to one of claims 1 and 2, characterized in that the station   pre-polishing (6) includes an animated pre-polishing plate support (40)   of a rotational movement relative to a fourth axis of rotation (s5).   4. Device according to claim 3, characterized in that the axis of symmetry (sl 1) of the magazine (9) and the third and fourth axes of rotation (sl and s5) are   arranged in the same vertical foreground.   5. Device according to claim 4, characterized in that the cleaning station 15 (7) has an axis of symmetry (s7), forming with the first axis of rotation (s8) of the sample holder (11), a second vertical plane perpendicular to vertical foreground.   6. Device according to any one of claims 1 to 5, characterized in that the gripper consists of three rods (29), the free end   of each rod (29) comprising a hook (30) making it possible to maintain the tray (19) by its periphery.   7. Device according to any one of claims 1 to 6, characterized in that the gripping arm (31) is integral with a guide column (32), it   even mounted on a vertical support (33) and being able to rotate around the   second axis of rotation (s4) thanks to two pivots (36, 37).   8. Device according to any one of claims 1 to 7, characterized in that   that the polishing station (8) comprises a supply arm (25) in liquid abrasives, connected to a plurality of pumps themselves connected to a   plurality of tanks (27) each containing a liquid abrasive.   9. Device according to claim 8, characterized in that the means for   control (15) control the pumps connected to the reservoirs (27), so as to choose the liquid abrasive as a function of the plate (19) disposed on the plate support (24) and to supply the supply arm (25) with liquid abrasive 10 during each polishing operation.   1O.Device according to one of claims 8 and 9, characterized in that the   control means (15) control the wear of the plates (19) and the quantity   liquid abrasive contained in each reservoir (27).