JP4484739B2 - Water jet nozzle device - Google Patents

Description

  The present invention relates to a water jet nozzle device for performing fine groove processing with a width of less than 100 μm on, for example, metals, substrates, glass and the like.

  For example, a laser processing machine may be used as an apparatus for processing fine grooves with a width of less than 100 μm on metals, semiconductor device substrates, glass, and the like. However, the laser processing machine has both high initial cost and running cost, which not only deteriorates productivity but also makes it difficult to maintain the processing quality without special knowledge of laser, and is not suitable for practical use.

  In addition to such a laser processing machine, a water jet injection processing machine that injects high-pressure water from a nozzle has been conventionally used (for example, see Patent Document 1). In this water jet injection machine, fine grooves are formed by continuous erosion by relatively moving the jet of high-pressure water while colliding with the work surface, but relatively deep grooves are required. In this case, an abrasive jet is used in which an abrasive is mixed with high-pressure water and jetted.

JP-A-6-320104

  However, in the fine groove processing by the conventional water jet spray processing machine, it is necessary to use masking that requires a complicated and troublesome process. As shown in the schematic diagram of FIG. 3, this is usually a water jet in a region where the injection distance L to the surface to be processed satisfies the condition of L / D (nozzle injection hole diameter) ≈150 as a water jet optimum for processing. This is because a “droplet flow region” containing a large amount of air flow is used.

  In other words, the jet in the droplet flow region has started to diffuse outward from the central axis in the jet direction to some extent, and in the groove machining in which the droplet flow region collides with the surface to be processed as a machining jet, the jet at the collision position Since the processing area determined by the cross-sectional area is relatively wide, 2 to 4 times the nozzle injection diameter, in the case of fine groove processing, on the surface to be processed, the processing area is substantially reduced. It was necessary to form a masking layer.

  In addition, in the groove processing by the super-high pressure jet flow, as shown in FIG. 2, since the groove width increases toward the surface side with respect to the depth direction of the groove processing, the upper groove width L1 on the surface side becomes the processing target value. However, even if a region with a relatively small jet cross-sectional area near the continuous flow region, which is a rectifying unit, is used, the groove edge portion is scraped by the collision of a jet having a slightly diffused region. A so-called surface sag occurs, and the substantial groove width becomes a wide region including the surface sag, and the groove width dimension cannot be kept within a minute target value of less than 100 μm without masking.

  In view of the above problems, an object of the present invention is to provide a water jet nozzle device that can easily process a groove having a fine width without using complicated means such as masking.

In order to achieve the above object, a water jet nozzle device according to a first aspect of the present invention includes an injection nozzle that is installed inside a housing and that injects a jet of ultrahigh pressure water into a flow path formed in the housing. A throttle nozzle that is installed on the end side of the flow path coaxially with the injection nozzle, introduces a jet flow injected from the injection nozzle, and injects it toward the processing surface, and is injected from the injection nozzle And a discharge water passage for discharging the shut-off water, which is shut off without being introduced into the throttle nozzle, out of the housing .

  A water jet nozzle device according to a second aspect of the present invention is the water jet nozzle device according to the first aspect, wherein the throttle nozzle is separated from the jet nozzle by a distance of 1300 times or less the jet nozzle diameter. It is what is installed.

A water jet nozzle device according to a third aspect of the present invention is the water jet nozzle device according to the first or second aspect , wherein the air assist mechanism supplies air into the housing for pushing out the blocking water in the discharge water channel. Is further provided.

A water jet nozzle device according to a fourth aspect of the present invention is the water jet nozzle device according to any one of the first to third aspects, further comprising an air blow nozzle that blows spray air onto the work surface. Is.

  In the water jet nozzle device of the present invention, the throttle nozzle is further provided on the coaxial downstream side of the injection nozzle for injecting high-pressure water, so only the core portion of the high-pressure jet flow injected by the injection nozzle is provided. Will be sprayed onto the work surface through the squeezing nozzle, a processing area smaller than the processing area by the jet obtained only by the injection nozzle will be obtained, and the width will be less than 100 μm without requiring complicated and laborious masking. There is an effect that it is possible to easily cope with fine groove processing.

  The present invention is a water jet device in which a throttle nozzle is installed at the end of the flow path coaxial with an injection nozzle that jets a jet of ultrahigh pressure water into a flow path formed in a housing. If the jet inlet diameter of the nozzle is set to a dimension corresponding to a desired central region of the jet jetted from the jet nozzle, the core portion of the jet jetted from the jet nozzle is introduced and directed toward the work surface. And jetted as a processing jet.

  That is, in the water jet nozzle device of the present invention, by interposing the throttle nozzle, the region of the jet flow ejected from the spray nozzle is blocked out, and only the jet in the central region is ejected. Therefore, the substantial processing area can be reduced on the apparatus side, and it is possible to cope with fine groove processing with a width of less than 100 μm without requiring complicated and laborious masking on the processing surface side.

  In addition, since the jet jetted from the throttle nozzle to the surface to be processed is also in the droplet flow region where the water jet contains a large amount of air flow, the jet jetted from the jet nozzle is directed to the throttle nozzle in the continuous flow region. It should be introduced. Therefore, the relative positional relationship of the aperture nozzle with respect to the ejection nozzle may satisfy the condition that there is a distance 200 to 1300 times the ejection nozzle diameter.

  This specific range of the inter-nozzle distance is obtained as a result of examining the relationship between the diameter D of the injection nozzle shown in FIGS. 4 and 5 and the distance A of the continuous flow region under a predetermined pressure (MPa) condition. That is, first, the distance A of the continuous flow region seen as a rectifying portion of each jet when the pressure is constant at 200 MPa and the injection nozzles have different diameters D = 20, 30, 40, 50, 60 μm is measured. / D value was determined. The results are as shown in FIG. 4 (X axis: injection nozzle diameter D μm, Y axis: A / D). Under the same pressure conditions, the distance A of the continuous flow region corresponds to the change in the diameter D of the injection nozzle. Except for the case where the diameter of the injection nozzle was 20 μm, the A / D value was almost unchanged at around 700.

  Therefore, when the diameter of the injection nozzle is fixed at 50 μm, the distance A of the continuous flow region of the jet is measured in the pressure range from 50 MPa to 350 MPa, and the value of A / D is obtained. FIG. MPa, Y axis: A / D). Water pressure required for injection processing cannot be obtained at pressures lower than this range, and a continuous flow region (rectifier) cannot be secured at high pressures exceeding this range, making it suitable for practical use as water jet injection processing. It can be said that it is a practical upper limit and a lower limit of the pressure range in which a jet can be obtained. Accordingly, a substantial range of the inter-nozzle distance A in which the jet flow injected from the injection nozzle based on the A / D values 200 and 1300 at the upper and lower pressure ranges can be introduced into the throttle nozzle in the continuous flow region, that is, the nozzle 200 to 1300 times the diameter D is specified.

  Further, in the present invention, of the jet flow injected from the injection nozzle, the blocking water blocked by the throttle nozzle in the region diffused outward accumulates in the housing as the injection time elapses and disturbs the injection shape. It is preferable to provide a drainage channel for discharging the blocking water to the outside of the housing.

  Furthermore, it is more preferable that an air assist mechanism is provided so that the blocking water in the discharge channel is pushed out with air so that the blocking water is efficiently discharged.

  In addition, if water droplets adhere to the surface or a water film is formed on the surface to be processed, the processing accuracy will deteriorate, so air will be blown to the surface to be processed during processing to prevent water droplets or water films from blowing off or adhere to the surface. It is desirable to provide an air blow nozzle for this purpose.

  A water jet nozzle apparatus as an embodiment of the present invention is shown in the schematic block diagram of FIG. The present water jet nozzle apparatus has a housing 1 arranged on a workpiece as an apparatus main body, and an injection nozzle 5 and a throttle nozzle 9 are arranged coaxially so as to inject a high pressure jet vertically downward. Is.

  That is, the injection nozzle 5 is attached to the lower end of the nozzle adapter 4 which is positioned and fixed on the upper side by mounting the nozzle cap 6, and the housing 1 in a state where the adapter lower region is inserted into the nozzle adapter 4 is provided as a guide. It is fixed by a hexagon bolt 3 so that the relative position can be adjusted in the vertical direction via the holder 2.

  Further, in this apparatus, a throttle nozzle 9 is attached to the housing 1 at a position on the end portion side of the flow path 7 on the same axis as the injection nozzle 5 by a nozzle holder 8 attached to the lower end. Therefore, the ultra-high pressure water jet supplied from the outside through the nozzle adapter 4 by the high pressure pump (not shown) and injected into the flow path 7 formed in the nozzle cap 6 by the injection nozzle 5 has a predetermined inlet diameter. Only the core portion is introduced into the throttle nozzle 9 and is injected toward the surface to be processed as a processing jet having a reduced cross-sectional area.

  At this time, out of the jets jetted from the jet nozzle 5, the jet water in the outer region that is blocked without being introduced into the throttle nozzle 9 stops inside the housing 1, but in this apparatus, the discharge water channel 10 is provided. Therefore, the shut-off water is discharged outside the housing to prevent the shut-off water from collecting in the housing and disturbing the jet shape of the jet. In addition, an air assist mechanism 11 for supplying air into the housing is provided so as to push out the water accumulated in the discharge water channel with air so that the shut-off water is efficiently discharged.

  Furthermore, in this apparatus, an air nozzle 13 that blows air onto the surface to be processed and an air chamber 12 that supplies air to the air nozzle 13 are provided on the outer peripheral portion of the housing 1. By blowing air with the air nozzle 13, it is possible to prevent water droplets and a water film from adhering to the processing surface to deteriorate the processing accuracy.

  In this apparatus, the housing 1 is bolted to the guide holder 2, and the position of the throttle nozzle 9 at the lower end of the housing 1 is adjusted by adjusting the position of the guide holder 2 with the hexagon bolt 3 with respect to the nozzle adapter 4. By adjusting this position, the relative positional relationship of the throttle nozzle 9 with respect to the jet nozzle 5 is such that the processing jet jetted from the throttle nozzle 9 becomes a droplet flow region suitable for erosion groove processing. Positioning can be performed to satisfy the conditions.

  The result of fine grooving on the alloy tool steel (SKD61) using the water jet nozzle device having the above-described configuration is shown below in comparison with the case where only the conventional injection nozzle is used. The processing conditions were the same for both, except for the diaphragm nozzle 9 in this apparatus.

  That is, with the upper groove width and surface sag region of 100 μm or less and groove depth of 2.5 mm or more as targets, the injection nozzle diameter is 50 μm, the pressure is 350 MPa, the high-pressure water feed speed is 100 mm / min, the processing jet distance (the injection position of the final jet) In the apparatus of the present embodiment, on the condition of 20 mm, the distance from the processing surface to 20 mm, the number of injections of 32 passes, and the air assist pressure of 0.2 MPa, the throttle nozzle 9 having an injection port diameter of 80 μm is moved downward from the end of the injection nozzle 5 by 10 mm Was positioned.

  Groove processing was performed with this apparatus and the conventional injection nozzle under the above conditions, and the dimensions of the upper groove width L1, lower groove width L2, depth D, and surface sag region width of the formed groove were measured, and the results are shown in the following table. Summarized in 1.

  As shown in Table 1, in the groove processing by the conventional injection nozzle, the upper groove width L1 is close to the target value, but the surface sag region is very large, and the substantial groove width including this surface sag region is approximately In contrast to the target value which is three times the target value, in the groove processing by the water jet nozzle device provided with the throttle nozzle 9 at the coaxial downstream position of the jet nozzle 5, the surface sag is not substantially generated, but substantially Processing with a typical groove width of 100 μm or less was possible without masking.

  The distance between the throttle nozzle and the injection nozzle may be set as appropriate so as to satisfy the above-described relative positional relationship between the injection nozzle diameter and the injection pressure of the injection nozzle actually used.

It is a longitudinal cross-sectional view which shows schematic structure of the water jet nozzle apparatus by one Example of this invention. It is a longitudinal cross-sectional schematic diagram which shows the groove part structure of the groove process by a super-high pressure jet flow It is explanatory drawing which shows the structure of a super-high pressure injection flow. It is a diagram which shows the relationship between the diameter D of the injection nozzle in the case of constant pressure, and the distance A of a continuous flow area | region. It is a diagram which shows the relationship between the diameter D of the injection nozzle in each pressure, and the distance A of a continuous flow area | region.

Explanation of symbols

1: Housing 2: Guide holder 3: Hexagon bolt 4: Nozzle adapter 5: Injection nozzle 6: Nozzle cap 7: (For jet) Channel 8: Nozzle holder 9: Restriction nozzle 10: Discharge water channel 11: Air assist mechanism 12: Air chamber 13: Air nozzle

Claims (4)

An injection nozzle installed inside the housing and injecting a jet of ultra-high pressure water into a flow path formed in the housing;
A throttle nozzle that is installed on the end side of the flow path coaxial with the injection nozzle, introduces a jet flow injected from the injection nozzle, and injects it toward the processing surface ;
A water jet nozzle device comprising: a discharge water passage for discharging a shut-off water, which is shut off without being introduced into the throttling nozzle, out of the jet jet jetted from the jet nozzle.   The water jet nozzle device according to claim 1, wherein the throttle nozzle is installed at a distance of 1300 times or less of an injection nozzle diameter with respect to the injection nozzle. Water jet nozzle according to claim 1 or 2, characterized in that the air to push the shut-off water of the discharge within the water channel further comprising an air assist mechanism for supplying into the housing. The water jet nozzle device according to any one of claims 1 to 3 , further comprising an air blow nozzle that blows spray air on a work surface.

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