FR3140293A1 - MACHINING DEVICE - Google Patents

Abstract

A machining device (101) includes a support (103) for holding a machining head (105) configured to produce an abrasive water jet (115) from a first flow pressurized water (109) and an abrasive material (113). The machining device (101) further comprises a cleaning head (117), held by the holding support (103), and configured to produce a cleaning water jet (123) from a second flow of water under pressure (121). Figure for abstract: Figure 1

Description

MACHINING DEVICE

The invention relates to the field of machining materials, in particular for the manufacture of mechanical parts of an aircraft. It concerns in particular a machining device.

In a known manner, the machining of materials for the manufacture of mechanical parts generates waste in the form of particles deposited or stuck to the surface of the machined material. Whether residual particles from a material used for abrasion or particles from the material that has been machined, it is necessary to use a cleaning technique to remove them from the surface of the machined material in order to get a clean machined part.

Thus, many cleaning methods are used including, ultrasonic cleaning, the use of a high pressure water jet, the use of a water bath and a recurring sponge, LASER, or even the projection of ice.

However, a major drawback of existing methods is the time associated with the different stages of their implementation, such as, for example, setting up for machining, machining, dismantling, transport, setting up for cleaning, cleaning and finally dismantling.

Another disadvantage of some of these methods lies in the fact that they are not very effective when the residual abrasive material is deeply embedded in the machined material (this is for example the case for high pressure water jet machining). in ductile materials).

Yet another disadvantage is the need to use a repetitive manual process which can lead to Musculoskeletal Disorders (MSD) and which requires the training of a qualified operator.

The present invention offers a solution to these drawbacks.

To this end, the subject of the invention is a machining device comprising a support for holding a machining head, said machining head being connected to a first conduit configured to admit a first flow of water under pressure and an abrasive material, and being configured to produce an abrasive water jet, at a first pressure value, from said first flow of pressurized water and said abrasive material,

said machining device being characterized in that it further comprises a cleaning head, held by the holding support, connected to a second conduit to admit a second flow of water under pressure, and configured to produce a jet of cleaning water, at a second pressure value, from the second flow of pressurized water.

The invention therefore makes it possible to carry out machining and cleaning operations simultaneously without requiring complex and/or time-consuming manipulations to be able to sequence these operations. In addition, the use of a single device for these operations simplifies their execution.

According to one embodiment, the first conduit comprises a first inlet for the admission of the first flow of pressurized water and a second inlet for the admission of abrasive material.

According to another embodiment, the machining device further comprises a storage tank for the abrasive material connected to the second inlet of the first conduit, preferably in a removable manner.

According to another embodiment, the holding support comprises fixing means configured to allow its attachment to an arm of a robotic movement system.

According to another embodiment, the machining head comprises a first nozzle and the cleaning head comprises a second nozzle, said first nozzle and second nozzle being configured to generate, respectively, the first pressure value of the abrasive water jet , from the first flow of pressurized water and the abrasive material, and, the second pressure value of the cleaning water jet, from the second flow of pressurized water.

According to another embodiment, the machining device further comprises a pump connected to both the first conduit and the second conduit, to supply the first flow of pressurized water and the second flow of pressurized water.

According to another embodiment, a first pump is configured to supply the first flow of water under pressure to the first conduit and a second pump is configured to supply the second flow of water under pressure to the second conduit.

According to another embodiment, the machining device further comprises a filter, arranged in a closed circuit comprising said machining device, and configured to retain impurities from machining discharge water, so as to that water intended to supply the first pump is produced at the outlet of the filter.

The invention according to a second aspect also relates to a machining method with a machining device comprising a machining head configured to produce an abrasive water jet and a cleaning head configured to produce a cleaning water jet , said machining process comprising:

- positioning a material to be machined on a fixing support located in an abrasion zone of the machining device;

- machining of the material to be machined, in the abrasion zone, by the abrasive water jet produced by the machining head;

- cleaning the material to be machined, in the abrasion zone, by the cleaning water jet produced by the cleaning head; And,

- removal of the material to be machined from the fixing support,

said machining process being characterized in that machining and cleaning are carried out concomitantly.

In particular, it can be provided that machining and cleaning are carried out without removing the material to be machined from the fixing support.

According to a particular mode of implementation of the method, the machining head and the cleaning head of the machining device are held by the same support for maintaining the machining device so that, during each movement of the device machining, the machining head and the cleaning head are moved together.

According to a particular mode of implementation of the process, the abrasive water jet has a first pressure value and in which the cleaning water jet has a second pressure value which depends on the first pressure value.

The present invention will be better understood and other details, characteristics and advantages of the present invention will appear more clearly on reading the description of a non-limiting example which follows, with reference to the appended drawings in which:

there is a schematic representation of a machining device according to a first embodiment of the invention;

there is a schematic representation of a machining device according to a second embodiment of the invention;

there is a schematic representation of a machining device according to a third embodiment of the invention; And,

there is a step diagram of a machining process according to one mode of implementation of the invention.

In reference to the , we will now describe an embodiment of a machining device 101 according to the invention.

In the example shown in , the machining device 101 comprises a support 103 for holding a machining head 105 and a cleaning head 117. The support 103 comprises two distinct arms 103a and 103b, which both extend from the same central trunk 103c, and which are configured to hold, respectively, the machining head 105 and the cleaning head 117. Furthermore, in the non-limiting example shown, these arms are configured to hold the machining head and the cleaning head so that they are both directed parallel to the same axis 117 are inserted by force (and therefore held after their insertion) in through holes respectively provided in the arm 103a and the arm 103b of the holding support 103.

The machining head 105 is connected to a conduit 107 which is configured to admit a flow of pressurized water (symbolized by the arrow) 109 (hereinafter called pressurized water) and an abrasive material 113. It is configured to produce an abrasive water jet 115, at a pressure value P1 (sufficient to allow the machining of a material placed in front of the jet), from the pressurized water 109 and the abrasive material 113.

Typically, the pressurized water 109 admitted into conduit 107 is demineralized water whose pressure has a value between 10 and 2500 bars. Furthermore, the abrasive material can be, for example, garnet, staurolite, olivine, crushed glass or copper slag.

Furthermore, in the example shown, the machining head 105 comprises a nozzle 129 which is configured to generate the pressure value P1 of the abrasive water jet 115, from the pressurized water 109 and the abrasive material 113. More precisely, the pressure value P1 at the outlet of the machining head 105 depends both on the value of the pressure of the pressurized water 109 at the inlet of the conduit 107, on the abrasive material 113 used and on the nozzle 129 used. For example, the length and the internal diameter of said nozzle 129 can contribute to increasing or decreasing the pressure at the outlet of the machining head 105 relative to the pressure value in the conduit 107. Thus, advantageously, the change of A nozzle can make it possible to adjust a pressure value of the abrasive jet leaving the machining head.

The jet formed at the outlet of the machining head is called "abrasive" in the sense that it makes it possible to machine various materials such as metals, ceramics, thermoplastic or thermosetting polymers, reinforced or not, by short fibers or long carbon, glass, aramid, etc.

More specifically, as an example, the metals can be titanium alloys, including TA6V, inconels, aluminum alloys, steel, etc. The ceramics can be silicon carbides, silicon nitrides, zirconium dioxide, alumina etc. The thermosetting resins can be a polyurethane, an epoxy, a polybismaleimide (BMI), a polyimide, a phthalonitrile. Thermoplastic resins can be PEEK (polyether-ether-ketone), PAEK polyaryletherketones or even PEI (polyether-ketone). The fibers can be glass, carbon, aramid, or SiC (silicon carbide) ceramic.

The machining of these materials allows, for example, the manufacture of mechanical parts for an aircraft or an automobile or even parts for nautical or railway equipment.

For example, for TA6V titanium, machining is done with an abrasive jet with a pressure value P1 of between 1400 and 2400 bars.

In the example shown in , the conduit 107 comprises an inlet 107a configured for the admission of pressurized water 109 and an inlet 107b configured for the admission of abrasive material 113. Advantageously, the use of the two independent inlets makes it possible, if necessary, to modify independently the type of pressurized water (for example, to use demineralized water or not) and the type of abrasive material used.

Furthermore, in the example also shown, a tank 125 for storing the abrasive material 113 is connected, for example in a removable manner, to the inlet 107b of the conduit 107. In this way, the pressurized water 109 and the material abrasive 113 mix in the conduit 107 before being projected by the nozzle 129 in the form of the abrasive jet 115. The term "removable" here designates the fact that the tank can be connected and disconnected from the inlet 107b (in a manner reversible), by a user of the machining device 101. Advantageously, when the reservoir 125 is removable, the abrasive material used can be replaced or modified easily and quickly by replacing the reservoir or its contents.

Finally, in the example shown, the holding support 103 comprises fixing means 135 (for example a thread) configured to allow its attachment to an arm 127 of a robotic movement system. Typically, the arm 127 makes it possible to move the machining device 101 as a whole to machine different zones of a material to be machined placed under the machining device 101. Advantageously, the machining device can thus be mounted or disassembled on one mobile system or another depending on needs.

As said above, in addition to the machining head 105, the machining device also includes the cleaning head 117 which is also held by the holding support 103. The machining head 117 is connected to a conduit 119 configured to admit a flow of pressurized water 121 (also called pressurized water in the following), and configured to produce a jet of cleaning water 123, at a pressure value P2, from the pressurized water 121 .

For example, the pressurized water admitted into conduit 119 can be demineralized water whose pressure has a value between 10 and 2500 bars.

In the case of the example of TA6V titanium taken above, cleaning becomes effective from a pressure value P2 equal to or greater than 1800 bars. Thus, the cleaning water jet can be a water jet devoid of abrasive (also called a pure water jet) at a pressure P2 equal to or greater than 1800 bars.

In some cases, the pressure values P1 and P2 may be equal.

More generally, the value of P2 can be adapted to the value of P1, for example by choosing P2 as high as P1 is high so as to optimize the cleaning efficiency as a function of the quantity of particles produced by the machining. As a non-limiting example, P2 can be equal to P1, to within 30%, or greater than or equal to P1, or included in a pressure interval [P1min, P1max] in which P1 is located for a phase l' machining considered.

The water jet leaving the cleaning head is called "cleaning" in the sense that its properties are adapted to allow the evacuation of particles resulting from machining and contained in so-called "evacuation" water which can then be recovered or not.

As in the case of the machining head, the cleaning head comprises a nozzle 131 configured to generate the pressure value P2 of the cleaning water jet 123, from the pressurized water 121. Here again, advantageously, adjusting the dimensions of the nozzle (in particular its internal dimensions) can make it possible to modify the value of the pressure P2 at the outlet of the cleaning head from the pressure value of the pressurized water 121 initially admitted in conduit 119.

In the example shown in , the abrasive water jet 115 and the cleaning water jet 123 are oriented towards the same zone called abrasion zone 133. Advantageously, the portion of a material to be machined 209 (visible at the ) can be machined and cleaned simultaneously. In other embodiments, the two jets can be oriented differently so that the device is moved to alternate machining and cleaning of the same material to be machined. In addition, the material to be machined 209 is positioned on a fixing support 217 which makes it possible to fix said material to be machined 209 (or the mechanical part to be machined) and to maintain it throughout the duration of the machining and cleaning operations. Thus, to reach the different areas targeted for machining/cleaning the material to be machined, either the fixing support 217 is moved under the machining device 101 (and therefore moves the material to be machined with it) or the machining 101 is moved above the mounting bracket 217 (or a combination of the two).

In reference to the , we will now describe another embodiment of a machining device 101 according to the invention.

In the example shown very schematically in , the machining device 101 comprises, in addition to the elements already described with reference to , two pumps 203 and 205. The two pumps are configured to supply the machining device 101, respectively, water under pressure 109, and water under pressure 121. In particular, the pump 203 supplies the water under pressure 109 to the conduit 107 of the machining head 105 and the pump 205 supplied the pressurized water 121 to the conduit 119 of the cleaning head 117 (described with reference to the ).

Furthermore, in the embodiment shown, the machining device 101 also comprises a filter 207. The filter 207 is arranged in a closed circuit 211 formed with the machining device 101. It is configured to retain impurities from an evacuation water 213 which comes from the machining of the material 209. Thus, after filtration of the particles contained in the evacuation water 213 (we also speak of decontamination), it becomes (pure) water 215 recovered to be injected into the pump 203 of the machining device 101 and become the pressurized water 109 which supplies the machining head 105.

Advantageously, the quantity of water consumed by the machining device 101 can thus be reduced.

Furthermore, in the example shown, unlike the machining head 105, the cleaning head 117 operates in an open circuit, that is to say it is continuously supplied with water without using water recovered from water already used in the machining of the material to be machined 209.

However, in an embodiment not shown, this could also be included in a closed circuit comprising a filter.

In the variant shown in , a single pump 203 is used to supply the pressurized water 109 and the pressurized water 121 to the machining device 101. This variant makes it possible in particular to guarantee a synchronized evolution of the two pressure values P1 and P2. Furthermore, in this case, the pressure values P1 and P2 of the abrasive water jet and the cleaning water jet can be made different, if necessary, by the use of two nozzles 129 and 131 having different parameters.

Finally, the invention makes it possible to combine machining means and cleaning means in a single device while retaining the possibility of adjusting the properties of two jets generated by the device depending on the material to be machined.

Advantageously, this both saves time and simplifies the process line by eliminating transport between a machining station and a cleaning station and possible storage of parts between these different operations.

In reference to the , we will now describe a mode of implementing a machining method according to the invention.

The machining method described can be implemented, for example, with a machining device such as the machining device 101 described with reference to Figures 1 to 3.

Generally, the machining method 300 is carried out with a machining device that includes a machining head configured to produce an abrasive water jet and a cleaning head configured to produce a cleaning water jet.

In what follows, by way of illustration and to facilitate understanding, the references associated with the elements of the machining device are those corresponding to the embodiments of a machining device as described in Figures 1 to 3.

Step 301 consists of positioning a material to be machined 209 on a fixing support 217 located in an abrasion zone 133 of the machining device 101. As described above with reference to the machining device 101, the abrasion zone 133 and a zone towards which the abrasive water jet 115 and the cleaning water jet 123 are oriented. The fixing support 217 is a support in which the material to be machined is held once positioned above. In other words, the material to be machined 209 can be mounted on the fixing support 217 so that the fixing support 217 and the material to be machined 209 are made integral until possible disassembly (removal) of the material to be machined. 209 of the fixing support 217.

Step 303 consists of machining the material to be machined 209, in the abrasion zone 133, by the abrasive water jet 115 produced by the machining head 105.

Step 305 consists of cleaning the material to be machined 209, in the abrasion zone 133, by the cleaning water jet 123 produced by the cleaning head 117.

Finally, step 307 consists of the removal (i.e. disassembly) of the material to be machined 209 from the fixing support 217.

Furthermore, in the machining method 300, the machining step 303 and the cleaning step 305 are carried out concomitantly. In other words, the abrasive water jet and the cleaning water jet act together on the abrasion zone 133 so that the residual particles produced by machining are immediately cleaned. In addition, the machining step 303 and the cleaning step 305 are also carried out without removing the material to be machined 209 from the fixing support 217, that is to say without having to carry out a material disassembly operation. to be machined 209 of the fixing support 217. Advantageously, all of the operations to be carried out for machining are both less complex (i.e. without multiplying potentially heavy assembly/disassembly operations) and faster (i.e. it is not no longer necessary to carry out machining and cleaning in a sequential and therefore time-consuming manner).

In a particular mode of implementation of the machining method 300, the machining head 105 and the cleaning head 117 of the machining device 101 are held by the same support of the holding 103 of the machining device 101 so as to that, during each movement of the machining device 101, the machining head 105 and the cleaning head 117 are moved together. Thus, if the machining device 101 is moved above the fixing support 217 (and therefore the material to be machined 209) the abrasive water jet 115 and the cleaning water jet 123 continue to act at the same position relative to each other (potentially superimposed).

Finally, the abrasive water jet 115 can have a pressure value P1 and the cleaning water jet 123 a pressure value P2 which is a function of the pressure value P1, as explained above.

Claims (11)

Machining device (101) comprising a support (103) for holding a machining head (105), said machining head (105) being connected to a first conduit (107) configured to admit a first flow of pressurized water (109) and an abrasive material (113), and being configured to produce an abrasive water jet (115), at a first pressure value (P1), from said first pressurized water flow (109) and said abrasive material (113),
said machining device (101) being characterized in that it further comprises a cleaning head (117), held by the holding support (103), connected to a second conduit (119) to admit a second flow of pressurized water (121), and configured to produce a jet of cleaning water (123), at a second pressure value (P2), from the second flow of pressurized water (121). Machining device (101) according to claim 1, in which the first conduit (107) comprises a first inlet (107a) for admitting the first flow of pressurized water (109) and a second inlet (107b) for the admission of abrasive material (113). Machining device (101) according to claim 2, further comprising a tank (125) for storing the abrasive material (113) connected to the second inlet (107b) of the first conduit (107), preferably in a removable manner. Machining device (101) according to any one of the preceding claims, in which the holding support (103) comprises fixing means (135) configured to allow its attachment to an arm (127) of a movement system robotic. Machining device (101) according to any one of the preceding claims, in which the machining head (105) comprises a first nozzle (129) and the cleaning head (117) comprises a second nozzle (131), said first nozzle (129) and second nozzle (131) being configured to generate, respectively, the first pressure value (P1) of the abrasive water jet (115), from the first pressurized water flow (109) and of the abrasive material (113), and, the second pressure value (P2) of the cleaning water jet (123), from the second flow of pressurized water (121). A machining device (101) according to any one of the preceding claims, further comprising a pump (203, 205) connected to both the first conduit and the second conduit, to provide the first stream of pressurized water (109 ) and the second flow of pressurized water (121). Machining device (101) according to any one of claims 1 to 5, in which a first pump (203) is configured to supply the first flow of pressurized water (109), to the first conduit (107) and a second pump (205) is configured to supply the second stream of pressurized water (121) to the second conduit (119). Machining device (101) according to claim 7, further comprising a filter (207), arranged in a closed circuit (211) comprising said machining device (201), and configured to retain impurities from a water of evacuation (213) of the machining, so that water (215) intended to supply the first pump (203), is produced at the outlet of the filter (207). A machining method (300) with a machining device (101) comprising a machining head (105) configured to produce an abrasive water jet (115) and a cleaning head (117) configured to produce an abrasive jet of cleaning water (123), said machining process (300) comprising:

• positioning (301) a material to be machined (209) on a fixing support (217) located in an abrasion zone (133) of the machining device (101);
• machining (303) the material to be machined (209), in the abrasion zone (133), by the abrasive water jet (115) produced by the machining head (105);
• cleaning (305) the material to be machined (209), in the abrasion zone (133), by the cleaning water jet (123) produced by the cleaning head (117); And,
• removing (307) the material to be machined (209) from the fixing support (217),

said machining method (300) being characterized in that machining (303) and cleaning (305) are carried out concomitantly. Machining method (300) according to claim 9, in which the machining head (105) and the cleaning head (117) of the machining device (101) are held by the same support for maintaining (103) the machining device (101) so that, during each movement of the machining device (101), the machining head (105) and the cleaning head (117) are moved together. A machining method (300) according to claim 8 or 9, wherein the abrasive water jet (115) has a first pressure value and wherein the cleaning water jet (123) has a second pressure value which depends on the first pressure value.