JP2751236B2 - Identification part of cast parts - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for determining the processing of a cast part such as a cylinder or a cylinder head of an engine.

[Conventional technology and its problems]

The cylinder head of the engine is cast and molded and finished by machining. The cylinder head is fastened to the upper surface of the cylinder, and a combustion chamber is provided in a portion facing the cylinder. The lower surface of the cylinder head is cut smoothly so as to be fastened to the cylinder. The cutting allowance changes the size of the combustion chamber and the compression ratio of the engine to change the engine performance. Therefore, a cylinder head having two kinds of performances is manufactured by changing the machining allowance of the lower surface with the same cylinder head.
In this case, even if the machining allowance is changed, it is about 0.5 mm, so it is difficult to visually determine the finished product. Therefore, when the cutting process is completed, the discriminating paint is applied to a part or the discriminating embossing is performed, which is troublesome. Similarly, for a cylinder, in the case of a two-stroke engine, the upper end position of the end of the exhaust hole determines the exhaust timing and greatly changes the engine performance. 0.5 m at the top of the exhaust hole
Sometimes it is possible to make a product that is changed by about m, but it is difficult to visually discriminate, and it is time-consuming to make a distinction by applying paint or embossing.

[Object of the invention]

According to the present invention, a projection is integrally provided on a side of a cast part to be cut, and when the tip of the projection is cut on a cutting surface, the tip is cut at the same time or left without cutting. It is an object of the present invention to obtain a device for determining the machining of a cast part in which protrusions can be determined without any trouble.

[Configuration of the invention]

 Hereinafter, the present invention will be described with reference to embodiments shown in the drawings.

FIGS. 1 and 2 show one embodiment of the present invention, and show the case of a cylinder head of a two-stroke engine. The cylinder head is a cast part 1 cast using a light alloy. A plurality of cooling fins 2 on the upper side
And a combustion chamber 3 that is recessed upward is formed in the center of the lower surface. The lower surface is a cutting surface 4, which is cut smoothly, overlaps the upper surface of the cylinder with a gasket in between, and is integrated by tightening. Therefore, the volume of the combustion chamber 3 can be changed depending on whether or not the cut surface 4 is excessively cut by the t dimension, and two types having different engine performances can be obtained by changing the compression ratio. Thus, according to the present invention, a projection 5 whose tip projects below the cutting surface 4 is integrally cast on the side 4 of the cutting surface 4 at the time of casting. That is, the cutting surface (joining surface) 4 of the cylinder head 1 is set in two stages of a large range A in which the moving range of the cutting tool with respect to the processing surface 4 is a small range B and a large range A including the small range B. A projection 5 serving as a discrimination mark is formed on the cylinder head 1 at a lateral position independent of the processing surface 4 and outside of the cutting range of the small range B and in the cutting range of the large range A. Provided. When the cutting surface 4 is cut, if the t dimension machining allowance is large, the range A is cut and the tip of the projection 5 is cut simultaneously, and if there is no t dimension, the range B is cut. The tip of the projection 5 is left without cutting.

FIGS. 3 and 4 show another embodiment of the present invention, and show a case of a cylinder of a two-stroke engine. The cylinder is a cast part 1 cast using cast iron.
It is. The upper surface is smoothed by a cutting process at a cutting surface 4, and the cylinder head is connected to the gasket. In this case, the upper edge of the entrance of the exhaust hole 6 determines the exhaust timing, and the dimension T with the cutting surface 4 becomes important. Just changing T by about 0.5mm can change engine performance. Also in this case, a projection 5 whose tip projects above the cutting surface 4 is integrally cast and provided on the side of the cutting surface 4. Further, the moving range of the cutting tool with respect to the cutting surface 4 is set in two stages of a small range B and a large range A, and the projection 5 deviates from the cutting range of the small range B and the cutting range of the large range A. And provided as a discrimination mark. Then, according to the change in the T dimension, one is cut in the A range and the tip of the protrusion 5 is cut simultaneously, and in the other case, the B is cut in the B range to leave the protrusion 5 unprocessed.

[Function of the invention]

The projections 5 can be visually judged to determine the difference in the processing dimensions depending on whether or not the tip is cut, thereby preventing an error when assembling. The projections 5 can be integrally cast when the cast component 1 is cast. Even when cutting the tip of the projections 5, the projections 5 can be cut at the same time as the cutting surface 4 is cut, so that no extra time is required. And it is easier to see than stamping.

〔The invention's effect〕

As described above, the present invention provides a projection on a side of a cutting surface of a cast part, and when cutting the cutting surface, the tip of the projection is simultaneously cut or left without being cut. As a result, it is possible to determine the machining status at the tip of the projection, so that the projection can be cut in one piece at the same time, without extra labor, and at low cost. Mistakes can be prevented. It is easier to see than stamping and does not peel off like paint.

[Brief description of the drawings]

 1 and 2 show an embodiment of the present invention, FIG. 1 is a bottom view, FIG. 2 is a longitudinal sectional view, and FIGS. 3 and 4 show another embodiment of the present invention. FIG. 3 is a plan view and FIG. 4 is a longitudinal sectional view. 1 ... cast parts, 4 ... cutting surface, 5 ... projections.

Claims (1)

(57) [Claims] 1. A cast component in which after joining the respective joining surfaces of two parts, the joining surfaces are superimposed and integrated, and the joining surface of at least one of the cast components is cut with respect to the joining surface. While the moving range of the tool is set in two steps of a small range and a large range including the small range, the casting part is a place independent of the joining surface and deviates from the cutting range of the small range. In addition, a projection is provided integrally with a casting within a large range of cutting area, and the tip of the projection is left during the cutting of a small area, and the tip of the projection is cut during the large range of cutting. The identification display section for a cast part, wherein the projection is used as a discrimination mark.