SU1710170A1 - Method for making three-dimensional parts with holes - Google Patents

Abstract

This invention relates to; to the processing of pressure and can be used to obtain spatial products with holes from sheet blanks. Objective > & expansion of technological capabilities 39 by obtaining spherical products and improving the accuracy of the holes. In a planar blank, a hole with larger and smaller bases is punched, and then the blank is deformed about the hole axis and gives a spherical shape around the hole portion of the blank around the hole. The ratio of the diameters of the larger and smaller bases of the hole is determined from the formula A = dS / R + d, where d is the average diameter of the hole in the finished product; R is the inner radius of the spherical surface of the product; S is the thickness of the workpiece; 6- the difference between the maximum and minimum diameters of the bases of the holes in the finished product. 1 hp ff. 3 silt. ^ The invention relates to pressure treatment and can be used to obtain spatial parts with precise holes from sheet blanks. Methods are known for obtaining spatial parts with holes, including the operation of obtaining a blank, molding and punching holes with whole getting the final detail. Moreover, to improve the accuracy of the hole, a stripping operation is used. The closest to the technical essence is the method consisting in punching a hole with a larger and smaller bases in the workpiece and subsequent deformation of the workpiece. A disadvantage is the inaccuracy of the resulting hole, having the shape of a truncated cone, due to the fact that there is a gap between the die and the punch or the need to use three or more transitions to obtain a part. The purpose of the invention is to expand the technological their capabilities due to obtaining products with a spherical surface and improving the accuracy of the holes. When punching a hole, the difference between the maximum and minimum diameters of its base is determined from the relation VJOL = d 'S R + d. where d is the average diameter of the hole in the finished product ; R is the inner radius of the spherical surface of the product; S is the thickness of the workpiece; d is the difference between the maximum and minimum diameters of the bases of the hole in the finished product.

Description

and in the process of deforming at least a part of the workpiece adjacent to the hole, they give the shape of a sphere with radius R of the inner surface, as well as the fact that, when deforming the workpiece, a convex spherical matrix is used. FIG. Figure 1 shows the scheme for obtaining the initial opening in the sheet stock; in fig. 2 shows the scheme for the final molding of the part and the hole; in fig. 3 The final shape of the part obtained and the hole. The method is carried out as follows. In a flat workpiece with a thickness S (Fig. 1), a hole shaped like a truncated cone is punched due to the presence of a gap between the die 2 and the punch 3 (the hole is characterized by larger and smaller diameters, the difference between which is A, and the average diameter d, whose value is equal to the arithmetic average larger and smaller diameters). The value of L is calculated in advance by the formula L. a. After receiving the hole, the workpiece is laid on the convex molding matrix with the base of the punched conical hole down (Fig. 2). Then the molding process is carried out. Moreover, due to the molding, the dimensions of the hole are changed so that the difference between the largest and smallest diameters decreases and becomes equal to b, and the part gets radius R at least near the hole. According to the proposed method, holes of 16 mm diameter are punched in aluminum sheet with a thickness of 5-8 mm with a difference of diameters A 1.1 mm. After forming a sphere with a radius of R 150 mm, the inaccuracy of the resulting hole is 6 0.28 mm, A 1.13 mm. The use of the invention makes it possible to reduce the machining allowance by approximating the size of the resulting hole to the nominal size of the part obtained. Moreover, to increase accuracy, a forming operation is used, as a result of which the method has wider technological capabilities. Formula 1 of 1. The method of obtaining spatial products with holes from sheet blanks, consisting in punching a hole in the workpiece with larger and smaller bases and subsequent deformation of the workpiece relative to the axis of the hole in the direction from the larger base of the hole to a smaller one with a simultaneous decrease in the angle of inclination of the forming surface of the hole, characterized in that, in order to expand technological capabilities by obtaining products with a spherical surface and increasing the accuracy of miles, when punching the difference between the maximum and minimum diameters of its base A is determined from the relationship where d - the average diameter of the apertures in the finished product; R is the inner radius of the spherical surface of the product; S is the thickness of the workpiece; (e) the difference between the maximum and minimum diameters of the bases of the holes in the finished product, and in the process of deforming at least a portion of the workpiece adjacent to the hole, the shape of a sphere with radius R of the inner surface is given. 2. The method according to claim 1, about tl and h and y and with the fact that when deforming the workpiece using a convex spherical matrix,

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Claims (2)

Claim 10 1. A method of producing spatial products with holes from sheet blanks, which consists in punching holes with larger and smaller bases in the blank and then deforming the workpiece relative to the axis of the hole in the direction from the larger base of the hole to a smaller one while reducing the angle of inclination of the surface of the hole, different 20 in that, in order to expand technological capabilities by obtaining products with a spherical surface and improve the accuracy of holes, when punching from ERSTU maksi25 difference between the normal and its minimum diameter. base Δ is determined from the ratio Δ = ^ + ό. where d is the average diameter of the hole in the finished product; R is the inner radius of the spherical surface of the product; S is the thickness of the workpiece; d - the difference between the maximum and 35 minimum diameters of the bases of the holes in the finished product, and in the process of deformation of at least the part of the workpiece adjacent to the hole, give the shape of a sphere with a radius 40 R of the inner surface. 2. The method according to claim 1, with the fact that when the workpiece is deformed, a convex spherical matrix is used. l muuuuuu u TU U7 \ Y /// y / ZZ /// ^ r ^ // Y // UU / T / UL • Figure 2 d Fig. 3