JPS6111968Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of an open cylindrical cast metal cover used for a rotating machine or the like.

Figures 1a, b, and c show conventional examples of cylindrical cast metal covers (brackets) for open-type rotating electric machines. In FIGS. 1a, b, and c, 1 is a cover peripheral wall, 2 is a ventilation hole, and 8 is a rib provided between the ventilation holes 2 in the axial direction. The ventilation holes 2 are formed at a plurality of locations in the circumferential direction and the axial direction of the cover peripheral wall 1, respectively.
However, in this cylindrical casting cover, since the position of the ventilation hole 2 is formed parallel to the central axis 4 of the cover peripheral wall 1, that is, at the same position in the radial direction, the ventilation hole 2 is formed during casting. Therefore, it was necessary to use a casting core, which had the disadvantage of requiring time and effort to form the casting, resulting in high costs. In addition, in order to eliminate the need to use a casting core, Fig. 2 a, b,
As shown in c, there is also a cylindrical cast metal cover in which only one ventilation hole 2, which is elongated in the axial direction and has a draft angle, is formed in the axial direction of the cover peripheral wall 1; In the case of a long type, the width of the ventilation hole 2 becomes narrower on the tip side due to the draft angle, resulting in a smaller ventilation area.
In addition, as shown in Figure 2 a, b, and c, ventilation hole 2
The reason why they are long and thin is to prevent people's hands from entering through the ventilation holes.

This invention eliminates the conventional drawbacks mentioned above,
The object of the present invention is to provide a cylindrical casting cover that is provided with ventilation holes that can secure a sufficient ventilation area, does not require the use of a core, is easy to manufacture, and is inexpensive.

Below, Figure 3a shows an embodiment of this invention.
In b and c, reference numeral 1 denotes a cover peripheral wall, which tapers in different diameters so that it becomes larger from one end where the bearing is fitted toward the other open end. 2
are ventilation holes, which are formed at a plurality of locations in the circumferential direction and width direction of the cover peripheral wall 1. Reference numeral 3 denotes ribs formed between the ventilation holes 2 in the axial direction, and these ribs 3 have their heights from the axis 4, that is, their radial positions, as shown in FIG. The ribs 3 are sequentially shifted in the axial direction so that the ribs 3 on the left end are the next lowest, and the ribs 3 on the right side of this are successively higher. In addition, by making the difference in height of each rib 3 slightly larger than the wall thickness of these ribs 3, the mold can be easily removed including the draft angle, and an efficient manufacturing process can be achieved without using a core. is possible. Figure 4 shows an example of a molded sand mold for producing the cylindrical casting cover shown in Figures 3a, b, and c, and in Figure 4, 5 represents the upper mold and 6 represents the lower mold. , a casting is poured into the space 7 formed by combining the upper mold 5 and the lower mold 6, and the products shown in FIGS. 3a, b, and c are cast. Before casting, by moving the upper mold 5 in the direction of arrow A and the lower mold 6 in the direction of arrow B, the upper mold 5 and the lower mold 6 are assembled, and a sand mold is completed without the need for a core.

As explained above, according to this invention, since the positions of the ventilation holes are sequentially shifted in the axial direction, that is, the radial direction of the ribs provided between the front and back, the ventilation holes are able to secure a sufficient ventilation area. Moreover, it has the advantage that it can be easily manufactured without using a core and can provide an inexpensive cylindrical casting cover.

[Brief explanation of the drawing]

Fig. 1 a, b and c show a front view, side view and partial side sectional view of an example of a conventional cylindrical cast metal cover, and Fig. 2 a, b and c show another example of a conventional cylindrical cast metal cover. A front view, a side view, and a partial side sectional view; FIGS. 3a, b, and c are a front view, a side view, and a partial side sectional view showing a cylindrical cast metal cover according to an embodiment of the invention; FIG. FIG. 3 is a partial side cross-sectional view showing an example of a mold for manufacturing a cylindrical cover according to an embodiment of the present invention. 1... Cover peripheral wall, 2... Ventilation hole, 3... Rib. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A plurality of ventilation holes 2 are provided at a plurality of locations in the axial direction of the cover peripheral wall 1, and the diameter of one end of the cover peripheral wall 1 is made different from the diameter of the other end, and each of the ventilation holes 2 is divided in the axial direction. A cylindrical cast metal cover for a rotating machine, etc., characterized in that the height of the rib 3 from the center of the cover shaft is gradually lowered from one end of the cover having a large diameter toward the other end of the cover having a smaller diameter.