Chain wheel sand mould and method for pouring chain wheel by using chain wheel sand mould

Abstract

The invention discloses a chain wheel sand mould and a method for pouring a chain wheel by using the chain wheel sand mould. The chain wheel sand mould comprises an upper shell, a lower shell and a sand core, wherein the middle portion of the upper shell is provided with a first middle hole, the upper shell is provided with an annular protrusion, a pouring ring is formed between the annular protrusion and the edge of the upper shell, the annular protrusion is provided with a first pouring channel, and the side of the upper shell is provided with a first sprue communicating with the pouring ring; the middle portion of the lower shell is provided with a second middle hole, the upper and lower surfaces of the second middle hole are provided with a first pouring cavity and a second pouring cavity correspondingly, and the position, corresponding to the first sprue, of the side of the lower shell is provided with a second sprue communicating with the second middle hole; the end of the secondpouring cavity is closed, and the lower shell is provided with a second pouring channel; the sand core is arranged on the annular protrusion in a sleeving manner; and the inner wall of the sand coreis provided with a gear cavity.

Description

technical field [0001] The invention relates to the field of hand wheel manufacturing, in particular to a sprocket sand mold and a sprocket casting method using the sprocket sand mold. Background technique [0002] The casting of metal castings generally uses coated sand molds as molding sand molds, and the sand molds are generally divided into upper and lower shells. The design of the shell needs to take into account the matching relationship between the shells, the flow of the molten metal during casting, that is, the rationality of the design of the runner. [0003] The traditional method of WG sprocket is the laminated sand-coated type, with two lower cores, one outer tooth, and one middle sand core. The amount of sand used is relatively large, and the sand ratio is about 2.8-3.1. The traditional process adopts the overlapping process. Two identical shells are required, and patterns are provided on both sides of the shell. In this case, the thickness of the sand mold is...

AI Technical Summary

Problems solved by technology

[0008] Sand mold clamping refers to the clamping of the upper mold and the lower mold. The gap between the upper mold and the lower mold will form burrs after casting. In severe cases, it will affect the product size and cause the casting to be scrapped. So how to use Better mold clamping of sand molds is a key link in determining the quality of castings

[0009] At the same time, the quality of the casting depends on the molding quality of the coated sand mold. In the traditional technology, the sprocket is generally made by the stacking process. A sand mold has molding cavities on both sides, and every two sand molds form a molding cavity for a casting. Therefore, the sand mold is Solid, thick, large amount of sand, high cost of sand, core coated sand is not easy to be heated and hardened, which affects the strength of the sand mold, uncured coated sand has a large amount of gas, and the casting has many pores and defects, resulting in the overall quality of the sprocket casting The rate is low; while the thickness of the sand mold using the shell molding process is relatively thin, the quality of the sand mold production is good, but only one sprocket casting can be cast at a time, the production efficiency is low, and the labor cost is high

[0010] At present, the traditional technology does not have a sand mold structure with both processes, and the same sand mold is used to superimpose the same sand mold multiple times, resulting in thicker sand molds and a larger sand ratio during pouring. At the same time, the formation of the middle position of the sand mold and The formation of gears requires multiple cores, the structure of the sand mold is complex, and the production process is cumbersome

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