JPH02191561A - Liquid atomizing nozzle - Google Patents

Abstract

PURPOSE:To form a good jet film by providing a tip and holder and a lower housing and upper housing enclosing the tip holder. CONSTITUTION:The tip holder 3 is fitted to the lower housing 5a opposite to an O-ring 13 and a back up ring 14 provided in an inside groove 12 of the lower housing 5a. The upper housing 4a is made into a cap nut shape and has holes 17 for the jaws of the wrench at the time of attaching and detaching the upper housing 4a and a thread part 18 so as to be screwed to the outer periphery of the lower hosing 5a. The upper hosing presses the tip holder 3 from the upper part to counter the pressure of a high-pressure liquid. Opening of nozzle tips 1a, 2a is executed by the pressure of the liquid and the max. value thereof is adjusted by the screw feed of the thread part 18. A lock nut 19 is used for position fixing. The spacing between the nozzle tips is maintained in the finest state at all times in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to an improvement in a liquid atomizing nozzle that produces atomized powder by jetting and colliding a high-pressure liquid with a molten liquid of molten metal, ceramics, polymer, or the like. [Prior art J Generally, in the production of metal powder, etc., a spraying means is used to make the molten metal flow down through a small hole, and the molten metal flow is bombarded with a high-speed spray medium from the surroundings to atomize the molten metal. Metal powder is obtained by cooling and solidifying. As an example of an atomizing nozzle for spraying this spray medium, Japanese Patent Application Laid-Open No. 1983-152605 (a device for spraying and pulverizing molten metal) is disclosed. This device makes it possible to produce fine metal powder from several um to more than ten micrometers by increasing the spray medium pressure from the conventional 200 kgf/cm2 or less to 500 kgf/cm2 or more. [Problems to be Solved by the Invention] As shown in FIG. ) 20 containing the melt of the object to be manufactured through the molten metal nozzle 21
The molten metal is atomized, cooled, and solidified by colliding with water as an atomizing medium to obtain metal powder. Normally, a closed injection annulus is formed, and a high-pressure pump introduces high-pressure liquid from the liquid supply pipe 7 into the liquid chamber 8, and the injection annulus with a closed gap is uniformly opened by the pressure of the liquid, and the spray nozzle is Together with the action of the reduced pressure chamber 22 provided at the bottom, this ensures uniformity of the liquid jet. However, in the nozzle of one device, the nozzle tip 1 is fitted into the upper housing 4, the nozzle tip 2 is fitted into the lower housing 5, and the lower housing 5 is fitted into the upper housing 4.
are connected to each other by a screw fitting part 23 and a fitting part 24. Ideally, the water ejected from the nozzle tip through the gap 1.2 forms a jet film 6 with a perfect inverted conical surface, as shown in FIG. 3(a), and melts toward the apex of this cone. When the metal flows in, the molten metal is crushed into fine particles by collision with the jet film 6, which hardens into fine powder.A jet film 6 with a perfect inverted conical surface is formed. In order to achieve this, the annular nozzle formed by the nozzle tips 1 and 2 must be composed of concentric circles on the same axis.In addition, this state is efficient in terms of powder production.As shown in Figure 2. If the central axis of the upper housing 4 and the central axis of the lower housing 5 are eccentric by ε, the gap between the nozzle tips 1 and 2 will not be uniform, and therefore the jet film 6 to be ejected will also be ), the state does not become uniform as shown in (C).In particular, in the case shown in FIG.
It will pass through. The reason why the central axis of the upper housing 4 and the central axis of the lower housing 5 are eccentric in this way is due to the structural defect of this device as described above, and the screw fit between the lower housing 5 and the upper housing 4 3.The reasons for the occurrence of these gaps are: ■Machining errors in the fitting part between the nozzle tip I and the upper housing 4; ■Machining errors in the fitting part between the nozzle tip 2 and the lower housing 5. This is because errors due to machining such as eccentricity between the upper housing 4 and lower housing 5 appear as an algebraic sum. The present invention was proposed in order to solve the above-mentioned problems, and aims to provide a liquid atomizing nozzle that improves the structural defects of the conventional technology and constantly forms an ideal jet film. It is something. [Means for Solving the Problems 1] The present invention solves the above-mentioned problems by ejecting high-pressure liquid from an annular nozzle consisting of upper and lower nozzle tips to form a fluid jet film with an inverted conical surface. , the first technical means was applied to a liquid atomizing nozzle that produces powder by letting the melt flow down to the top of a conical membrane. In other words, ■ a tip holder provided with a cylindrical hole that holds the upper and lower nozzle tips on the same axis, and ■ a lower part equipped with a high-pressure liquid supply path that surrounds and holds the tip holder from below and supplies high-pressure liquid to the tip holder. with housing. ■Consists of a lower housing on the right side and an upper housing that fixes the tip holder. [Operation] As shown in FIG. 4, the nozzle according to the prior art. Since the nozzle tip 1 and the upper housing 4 and the nozzle tip 2 and the lower housing 5 are fitted individually and are combined, eccentricity between the nozzle tip 1 and the nozzle tip 2 is unavoidable, and the gap between each nozzle tip is It is impossible to observe whether or not they are held concentrically. Furthermore, since the lower housing 5 is screwed into the upper housing 4, as the lower housing 5 is screwed in, the nozzle tip 2 also rotates relative to the stationary nozzle tip l, so the lower housing 5 is eccentric. In this case, it becomes increasingly difficult to manage the gap between the nozzle tip 1 and the nozzle tip 2. The present invention does not directly combine the nozzle tip 1 and the upper housing 5 and the nozzle tip 2 and the lower housing 5, but instead uses a tip holder having a cylindrical hole that holds the nozzle tip 1 and the nozzle tip 2 on the same axis. It stores and holds the chip holder firmly in the lower housing, and
Since the structure is such that the lower housing and the tip holder are fixed by the upper housing, it is possible to solve the problem that the central axes of the upper and lower nozzle tips are eccentric. [Example] Fig. 1 shows an explanatory diagram of an embodiment of the liquid atomizing nozzle of the present invention. Fig. 1(a) shows a cross-sectional view, and Fig. 1(b) shows a plan view of a liquid inflow pipe 7a. . The present invention includes a tip holder 3 provided with cylindrical holes 3a and 3b for holding the upper nozzle tip la and lower nozzle tip 2a on the same axis, a liquid chamber 8a, and a high-pressure liquid supply pipe 7a, and a tip holder 3 surrounding the tip holder 3. A lower housing 5a equipped with a high-pressure liquid supply pipe 7b that is held from below and supplies high-pressure liquid from the intake port 16 to the supply pipe 7a of the chip holder 3, the lower housing 5aJ, and the chip holder 3.
It consists of an upper housing 4a for fixing. As shown in FIG. 1(b), the high-pressure liquid supply pipes 7a are arranged radially and supply high-pressure liquid to the liquid chamber 8a. 9 is an O-ring for sealing, and 11 is a knock pin which is provided with a U groove 1.0 in the lower housing 5a and engages with this groove IO to fix the tip holder 3 to the lower housing 5a. The chip holder 3 is fitted into the lower housing 5a facing an O-ring 13 and a backup ring 14 provided in an inner groove 12 of the lower housing 5a. Note that 15 is a circular groove. The upper housing 4a has a cap nut shape and is provided with a spanner claw hole 17 for attaching and detaching the upper housing 4a and a threaded portion 18 to be screwed into the outer periphery of the lower housing 5a. resisting pressure. In addition, the opening of nozzle tips [a] and 2a is performed by the pressure of the liquid (when the liquid pressure is applied, 18 sticks to the top and 2a to the bottom), but the maximum value is adjusted by the screw feed of the threaded part 18, A lock nut 19 is used to fix the position. The tip holder 3 allows drilling of holes on the same axis of the same part, and the cylindrical hole 3a that holds the nozzle tip 1a and the cylindrical hole 3b that holds the nozzle tip 2a are formed from the arrow side during lathe processing and polishing. Can be constructed. Further, the nozzle chips la and 2a are assembled in advance into a single chip holder 3 placed on the workbench, and the nozzle chips 1aj5 and 2a
Since it is possible to observe and measure the uniformity of the chip spacing, the chip spacing can be set to the best condition. This nozzle tip
If the chip holder 3 incorporating the chips 2a and 2a is installed in the upper and lower housings 4a and 5a, the state set on the workbench will be maintained, allowing optimal operation. Therefore, unlike in the prior art, the axes of the nozzle chips I and 2 do not shift, and the axes of the nozzle chips Ia and 2a can be perfectly aligned, and the jet film has an ideal shape. Table 1 shows a comparison of the spray results using the nozzles of the present invention and the conventional nozzles. Furthermore, the spraying conditions are as follows. Nozzle tip diameter: 18mm Cone apex angle: 30° Water pressure: 100100O/crrIt Molten metal nozzle diameter: 2.5mm. According to Table 1, it can be seen that the particle size distribution of the powder obtained by the nozzle of the present invention is much better than that of the conventional example. [Effects of the Invention] The liquid atomizing nozzle of the present invention makes it possible to maintain the nozzle tip gap in the best condition at all times, and therefore has an extremely excellent effect on efficient production of metal powder and the like.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the present invention, and FIG.
) is a sectional view, FIG. 1(b) is a partial plan view of the liquid inflow pipe arranged in the chip holder, FIGS. 2 to 4 are explanatory views of the conventional example, and FIG. A cross-sectional view when the central axes of the upper and lower housings are eccentric, Figure 3 shows an example of the shape of the jet film corresponding to the eccentricity of the central axes of the upper and lower housings, and Figure 3 (a) is when there is no eccentricity. , FIG. 3(b) and FIG. 3(c) are eccentric, and FIG. 4 is a sectional view. 1, la... Nozzle tip 2.2a... Nozzle tip 3... Chip holder 3a, 3b... Cylindrical hole 4.4a... Upper housing 5.5a... Lower housing 6... Jet film 7.7a, 7b...supply pipe 8
．． 8 a-Liquid chamber 9.13-0 ring 10...U groove 11...Knock bottle 12...-inner groove
14... Backup ring 15... Full
16...Intake port 17...Spanner claw hole 18...
Threaded part 19... Lock nut 20... Molten metal flow 21... Molten metal nozzle 22... Decompression chamber 23... Threaded part 24... Fitted part ε... Eccentricity (b)

Claims (1)

[Claims] 1. High-pressure liquid is ejected from an annular nozzle consisting of upper and lower nozzle tips to form a fluid jet film with an inverted conical surface, and the melt is flowed down to the apex of the conical film to produce powder. In the liquid atomizing nozzle, a chip holder provided with a cylindrical hole that holds the upper and lower nozzle chips on the same axis, and a high-pressure liquid supply path that surrounds and holds the chip holder from below and supplies high-pressure liquid to the chip holder. 1. A liquid atomizing nozzle comprising: a lower housing having a tip holder; and an upper housing fixing the lower housing and the tip holder.