JPS6170169A - Preparation of fuel injection nozzle - Google Patents

Abstract

PURPOSE:To markedly improve workability by shaping a fuel injection nozzle into a specific shape divided into two parts in a fuel accumulation part and sintering and finishing-working said nozzle and positioning and joining the two-divided parts. CONSTITUTION:A fuel injection nozzle made of ceramics has a valve hole 1 at the center, and has a fuel feeding hole 2 on the periphery and a thin fuel injection hole 3 at the top edge. In a fuel accumulation part 4, ceramics-material powder is shaped into the two-divided form in the direction perpendicular to the longitudinal direction of the nozzle and sintered and finishing-worked. Then adhesive is applied onto a joint surface 5, and the joint surfaces 5 of the both members are joined by heating the both at 1,000-1,500 deg.C in the air. Therefore, the workability can be improved markedly, and mass production is permitted.

Description

Detailed Description of the Invention "Industrial Field of Application" Akira Kinki relates to a method for manufacturing fuel injection nozzles used in engines, etc., and includes 1) the production of fuel injection nozzles made from ceramics; ′! 1 nozzle/J nozzle manufacture') Shield IJ
It concerns i person.

[Prior art 1] Fuel injection nozzles, which are generally used in deep-pill engines, are involved in the combustion of diesel engines and are constantly used in harsh conditions of high temperature and stability.On the other hand, diesel As engines become more insulated, the area around the combustion chamber becomes even hotter.
I was able to do it.

This high-temperature F'l load causes conventional metal fuel injection nozzles to fail due to seizure, wear, and erosion. ! Attempts have been made to manufacture I-injection nozzles.

Conventionally, the following methods have been used to manufacture such ceramic combustion injection nozzles.

For example, ceramic moon R11 powder is formed into a round bar shape using a cold still water F111 nozzle, 1; sintered with a width T apart, and then ground using a grtt and T shell.
``a'' J jj5 method, or (by mixing aramic material r1 powder and ai!! binder, molded body 4 having valve holes, fuel supply holes, and fuel supply holes by injection molding method) After forming and sintering, Guillemond T shell (
For those who are in charge of RIJ, suffering is being done.

In the former cold still water Iffl nos. preheating T method, a round bar shape is machined 11. : A large amount of machining allowance is required, and (1
There is a drawback that fl is low, and it is difficult to add T in the state before sintering. In order to make it work, if it is added without securing enough strength to withstand machining: T L / ', r 1), it will not be possible to break IFI l, 1.
Emit a crack/1sal! However, it has the drawback of poor yield.

In this case, the injection molding method on the rear right, the valve hole, the fuel 11
Supply hole, burn f! Yield is improved because 4 molded bodies with 1 nozzle and 1 hole are molded at the same time. However, most of them are 5f
If you buy a core and mold it in Figure 1, it will be impossible to remove the core. 11 Noh and 4T, so the second
It was not possible to form the fuel reservoir portion 4 as shown in the figure. Therefore, after sintering, this part of the fuel reservoir must be machined out using a diamond shell, which requires a long time to process.

[Means for Solving the Problems 1] In view of the above points, the present invention includes various inspections of 5 dimensions. 1
：As shown in Figures 3 and 4, the fuel reservoir 4 in Figure 1 shows the nozzle in the f direction and in the iiJ angle direction.
Is it possible to cut each piece into a divided shape? Lamic IJ r! By molding, sintering, and sintering the I powder, placing the two parts on the I◇H table, and joining them together, the processing of the fuel F4 reservoir 4 can be omitted and the workability has been significantly improved.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

Figure 1 shows a ceramic fuel injection nozzle manufactured according to the present invention, with a valve hole 1 in the center and fuel supply holes 2 around the periphery. It has a small fuel injection hole 3 at its tip.

- Regarding the production of ceramic fuel injection nozzles with the structure described in F/j method [Todoroki; 1 Ming 4 and 1? Ramitsuku Shrine 1F + powder [1.1, 1-component is silicon nitride (Si, qN4), and sintering aid and organic binder are added and mixed 1)
As the sintering aid, for example, yttrium oxide (Y2
In addition to 8-type oxides such as 0a), aluminum oxide lx
(△I20a>, aluminum nitride (△IN), hardened silicon <S!02), and several types of these are mixed and used as -C. In addition, as an organic binder,
These include poly J-blen, acrylic resin, paraffin wax, etc., and serve to give II and moldability to the powder.

The lr molded body as shown in Figs. 3 and 4 was made by injection molding the 1N powder to which f1 machine binder was added.
Curling molding 11.

Next, these molded bodies were heated to 1700 to 200 in a nitrogen atmosphere.
After heating to 0°C and sintering at normal pressure, the necessary parts such as the valve hole 1° and the joint surface 5 are sealed with a diamond tool.
Geka l (! line). Furthermore, the joint surface of the product shown in Figures 3 and 4! ), kaolin and calcium fluoride (CaF2
) and fluoride (Nal'>M), apply an adhesive containing a mixture of halogen compounds (Nal'>M), and then heat the joint surfaces of both together to 1000-1500°C in air to join them together. , the ceramic fuel 1F1 injection nozzle shown in Figure 1!
It goes up to FJ.

"Example" Next, examples of the present invention will be described.

3i3N as the main component, and Y2 as a sintering aid.
5% of 0a, 4% of △1203, 4% of △IN, and 5% of acrylic resin as an organic binder, 5% of paraffin wax, 7% of polyethylene, and a plasticizer (I')
, F3. By injection molding 0 mixed with 2% P,
Small-sized products were molded as shown in Figures 3 and 4. Next, these molded bodies were removed from the binder and heated to 180°C in N2 gas.
Heat to 0°C and sinter under normal pressure to form valve hole 1. The joint surface 5 was finished by grinding with a diamond grindstone. Furthermore, a solvent for printing ink was added to a mixture of kaolin and CaF2 at a mixing ratio of 420 and thoroughly kneaded on the joint surfaces of both parts. The 18 mating surfaces were dried for 111 t!'r and then joined by heating in air to 14!

Total 1 (52111111 shown in Figure 1 of M structure 1 - Ramic combustion 1 point 0 = 1 nozzle was manufactured.

Next (J ratio◆☆Example (explanation l)).

The same formulation as in the example was prepared in the shape shown in Fig. 2 (Jq
・Molded in one piece. Next, after removing the binder and IC, it was heated to 1800°C in N gas and sintered at normal pressure.
＋Yes, it's good for the history ＼' Add the valve hole 1 by 1-1 with Lund Nagishi, and carve out the combustible 1 reservoir part 1. A Geramitsu fuel injection nozzle as shown in the 1st PI was manufactured. In the wood method, there is a high probability that cracks will occur in the molded product during debinding 15, resulting in poor yield.

This J: sea urchin in this example has 19 ramic IC and lamic fuel r
The nozzle for 1 injection can be changed to the one obtained in the 1L comparative example, and there is no need to cut out the fuel reservoir, so the production of :l can be reduced by about 50%, and the molding process can be reduced by approximately 50%. The shape is approximately 1. '2, the incidence of cracking defects during molding and ni + binder T culm is also reduced, and the performance of the nozzle is +5) in normal use. is.

[Efficacy of invention 1 i! 51 As clarified, the present invention has the following 3.
1.571 effect.

■Compared to the conventional cold isostatic pressing and pre-forming methods, the shape is formed during the molding stage by injection molding, which significantly improves workability and makes it suitable for nR. .

■It could not be molded using conventional injection molding methods. Since the fuel reservoir part is formed and 1q is formed, there is no need for machining by diamond cutting IQ, and the workability is significantly improved, making it suitable for close use. In addition, since the molded shape becomes smaller, molding,
It is possible to reduce the defective growth rate associated with binder removal, resulting in a reduction in defective generation/F.
By reducing the production rate, the yield is also suitable for 61 production.

[Brief explanation of the drawing] FIG. 1 is a sectional view of a fuel injection nozzle according to the present invention. FIG. 2 is a sectional view of a molded body according to a comparative example, and FIG. FIG. 4 is a cross-sectional view of the molded body according to the present invention.

Claims (3)

[Claims] (1) In manufacturing a ceramic fuel injection nozzle having a valve hole, a fuel supply hole, a fuel injection hole, and a fuel reservoir, the nozzle is divided into two parts at the fuel reservoir in a direction perpendicular to the longitudinal direction of the nozzle. Each ceramic raw material powder is injection molded, sintered, and finished, and the two are aligned.
A method for manufacturing a ceramic fuel injection nozzle, characterized by joining. (2) The method for manufacturing a ceramic fuel injection nozzle according to claim 1, wherein the ceramic raw material powder is silicon nitride and a sintering aid. (3) A method for manufacturing a fuel injection nozzle according to claim 1, characterized in that the joining is performed with a mixture of a halogen compound and kaolin interposed therebetween.