JPS607874Y2 - Core holder for impeller - Google Patents

Description

[Detailed description of the invention] This invention relates to a core for an impeller that constitutes the space between each impeller blade in a fluid machine having an impeller such as a pump, and is made of wood, metal or synthetic resin. It consists of:

Conventionally, when manufacturing this type of core, if the twist of each blade was small, the space between each blade and the outside and inside of the blade could be integrated, and the member forming the space of the latter blade made of hardened sand could be extracted and manufactured. However, in many cases, each blade is significantly twisted (and in such cases, it is extremely difficult to manufacture a core that integrates the whole into one piece).

Therefore, in order to manufacture an integrated core, it is also possible to use solder to create the spaces for each blade, remove the removable mold made of hardened sand, and remove the waxed parts by heating and melting them. However, the problem is that it takes time and effort to remove the waxy parts.

Another method is to manufacture the space between each blade and the parts extending outside and inside separately and use them in combination, but this requires a lot of labor and costs. It was something.

This invention solves these problems and provides a core holder for an impeller that allows the core to be manufactured very easily even in the case of highly twisted blades.

An embodiment of this invention will be described below with reference to the drawings.

Fig. 1 shows a mold for an impeller in which this invention is implemented, and this mold consists of a lower mold 10, an upper mold 11, a core 12 forming a space for mounting the central shaft, and 5 forming a space between each blade. It has a core 13 of.

Each of these cores was manufactured by the core removing method according to this invention, and the details of the core removing method will be explained below.

In Figures 2 to 4, reference numeral 15 denotes a wooden base member, which has an annular concave inner peripheral surface 16 that forms the outer peripheral surface of each core around the periphery, and protrudes upward toward the center. It has a protrusion 17 that is designed to

Reference numeral 18 denotes a metal blade space member that forms a space for each blade, and a partition plate 19 extends outward from the outer end and bites into the base member 15 to reach the outer end surface of the core 13. are fixed as one piece, and a partition plate 20 extending from the inner end toward the top inward and reaching the inner end surface of the core that bites into the protrusion 17 of the base member 15 is fixed as one piece. It is.

Both of the partition plates 19 and 20 are made of thin metal plates, for example, about 0.3 TML or less.

Reference numeral 21 denotes a pair of projections that protrude downward from the blade space member 18 and can be removably inserted into the base member 15.

After the blade space member 18 is attached to the base member 15 and the space between each blade space member 18, partition plate 19, and partition plate 20 is filled with sand and hardened, the upper surface of the protruding portion 17 of the base member 15 is filled with sand. Scraping board 2 having a removably fitted protrusion 23
2 to scrape off the excess sand and make it into a roughly predetermined shape.

Next, the scraping plate 22 is removed, a pair of frame members 25 are arranged around the base member 15 in engagement with each other, and the rear frame member 25 is filled with sand and hardened near the top and center of the partition plate 20. Remove.

When the sand is shaped into a predetermined shape by the scraping board 22, the frame member 2
5 may not be used.

Next, a gas is supplied to bind the sand and solidify the sand.

After that, when the base member 15 is removed, each blade space member 18 and the core 13 formed therebetween can be separated from each other and taken out.

Since the core 13 is placed at a position slightly shifted toward the center by a dimension due to the thickness of the partition plate 20, all dimensions should be determined with slight correction in mind if necessary. The blade space member 18 may be made slightly thicker than the actual blade.

As mentioned above, according to the core removing method of this invention, even when the blades are so twisted that the space between each blade cannot be made into a single common core, multiple cores forming the space between each blade can be used. The elements 13 are formed at one time, which has the effect of significantly reducing labor and cost.

In addition, in this invention, the core holder is mainly made of wood, but can also be made of metal or synthetic resin.

In the case of metal or synthetic resin, sand is sprayed from the opening at the center of the upper part of the frame member 25 using the base member 15 in which air vent holes are formed between each blade space member 18 without providing the scraping plate 22. Alternatively, the core may be formed by

Also, one or both of the partition plates 19 and 20 may be fixed to the base member 15 without being fixed to the blade space member 18, but when the partition plate 20 is fixed to the base member 15, the base member Reference numeral 15 in FIG. 3 indicates that the partition plate 20 can be cut horizontally at the lower end so that the upper part can be separated and overlapped at a predetermined position, so that there is no problem in taking out the core 13.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing a mold manufactured using a core taker according to this invention, Fig. 2 is a partially cutaway plan view showing an embodiment of this invention, and Fig. 3 is a longitudinal sectional view thereof. FIG. 4 is a perspective view showing the blade space member to which the partition plate is attached. 10 is the lower mold, 11 is the upper mold, 12 is the core, 13 is the core, 1
5 is a base member, 18 is a blade space member, 19 is a partition plate, 2
0 is a partition plate, 21 is a protrusion, 22 is a scraping board, and 25 is a frame member.

Claims (1)

[Scope of utility model registration request] A core holder for an impeller that forms a plurality of cores for forming the spaces between each blade of an impeller, the core holder being detachably attached to a base member and forming a plurality of cores for forming the spaces between each blade. A plurality of blade space members for configuring the blade space member, a thin partition plate that partitions a space that extends from the outer end of each blade space member to the outer end surface of each core, and a thin partition plate that continues from the inner end of each blade space member to the outer end surface of each core. 1. A core holder for an impeller, comprising: a thin partition plate that partitions the inner end surface of each core.