SU1581450A1 - Method of producing stamped articles - Google Patents

Abstract

The invention relates to the processing of metals by pressure and can be used in the manufacture of products by stamping to form scrap and its subsequent separation by a punch. The purpose of the invention is to improve the quality and reduce the labor intensity by increasing the purity of the compartment. When stamping, they form a flake, inclined to the axis of the forging. In the process of separation, the obdus is pushed against a cut matrix from the side of the acute angle and the axis of the forging, after which the punch bends over the oblo, constrained by lateral support for at least part of the working stroke. It is cut by the same stroke of the punch. The angles of inclination of the burr to the axis of the forging, the size of the technological gap between the burr and the element of the transverse backwater with the bar resting in the trimmed matrix are regulated. It is also provided for small angles of inclination to the axis of the forging to use a cut matrix with a surface against which the burr rests, convex in the direction of the inclination at an angle to the axis exceeding the inclination angle of but not less than 90 °. This makes it possible to reduce the deflection of the oblo and prevent its rupture and buckling in the form of stability. Due to the constrained bending during separation, compressive stresses are provided all over the region, including in the cutting zone, which increases the separation purity and prevents the accumulation from closing between the punch and the die, as a result of which no stripping is required. At the same time, the method does not require complicated tooling as in other known methods of finishing separation. 4 hp ff, 4 ill.

Description

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, (21) 4458449 / 31-27 (22) 07.07.88 (46) 07.30.90. Bul "28

(71) Moscow Institute of Instrument Engineering

(72) L.L. Vorontsov

(53) 621.73 (088.8)

(56) Forging and forging steel. Handbook ed. M.V. Storozheva. T. 2, I .: Mechanical Engineering, 1968,

with. 68-69, fig. 2

(54) METHOD FOR OBTAINING EMBOSSED PRODUCTS

(57) The invention relates to the processing of metals by pressure and can be used in the manufacture of products by stamping with the formation of scrap and its subsequent separation by a punch. The purpose of the invention is to improve the quality and reduce the labor intensity by increasing the purity of the compartment. When stamping, they form a flake, inclined to the axis of the forging. In the process of separation, the obdus is pushed against the edged matrix on the side of the acute angle and the axis of the forging, after which the punch bends back the oblo, constrained

at least part of the working stroke. It is cut by the same stroke of the punch. The angles of inclination to the axis of the forging, the size of the technological gap between the burr and the element of the transverse backwater with an emphasis on the trimmed matrix are regulated. angle to the axis, I exceed P1 the angle of slope of the burst, but less than 90. This makes it possible to reduce the deflection of the oblo and prevent its rupture and buckling in the form of stability. Due to cramped bending during separation, compressive stresses are provided all over the region, including in the pruning zone, which increases the separation purity and prevents the pad from being tightened between the punch with the matrix, as a result of which cleaning is not required. At the same time, the method does not require complicated tooling as in other known methods of finishing separation. 4 hp A-ly, 4 Il.

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The invention relates to the processing of metals by pressure and can be used in the manufacture of articles by stamping to form flash.

The purpose of the invention is to improve the quality of the forgings by improving the frequency of flash separation and reducing the labor intensity.

FIG. Figure 1 shows the start time (left) and the end time (right) of the stamping to form an oblique oblo; in fig. 2 - the moment of the beginning of the separation of the flash (on the left) and the moment of the touch of the transverse support element by the flash (on the right); in fig. 3 - the moment of the end of the constrained bending about

on (left) and the end of trimming oblo (right); in fig. 4 - the initial position of the forging with a cut patrice with a convex thrust surface (left) and the position of the forging at the moment before cutting (right). The method is carried out as follows.

In the stamp (Fig. 1, left), including the lower 1 and upper 2 halves, forming a stream-shaped groove corresponding to the shape of the resulting product and an oblique groove inclined to the axis, put the initial billet 3, which is stamped to obtain a forging 4 with a gullet 5 inclined to its axis is at an acute angle with / (Fig. 1, right). Then, the stamped forging is placed in a trimmed matrix 6, equipped with a transverse back-up member 7 (Fig. 2, left), abutted against a matrix on the side of an acute angle. Since the width of the circle varies somewhat from punching to punching, a gap A should be provided between it and the transverse backing element 7, which provides free loading of the forging into the cutting matrix. Then, the punch 8 starts to move the forging in the direction of the cut matrix 6, bending the curl, free before the clearance of the gap, and then (Fig. 2, right), the abutment. element 7 of the transverse sub- platform. Pa and the rest of the working stroke, there is no longer a free, but a constrained bend. As a result of transverse backing, the burrs are forced to shorten their original width 1, i.e. shrink. As a result, at the moment of contact of the cutting edge of the die (Fig. 3, left), the pressure across the entire thickness covers compressive stresses, large in the upper part and smaller in the lower part, since the latter elongates first and then shortens. Such a distribution of stresses leads, due to compressive stresses, to a significant increase in the purity of the separation during the further course of the punch (Fig. 3, right) Since a significant compression is achieved in the upper part of the circuit at the time of separation, this prevents the gap between the J punch and the matrix even when the latter is worn, as tightening requires even more compression in

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this part, and it is already large enough. As a result, a clean cut surface is obtained that requires almost no rework.

In order to guarantee the constrained bending on the part of the working stroke, it is necessary that the width about 1 (Fig. 2 on the left) exceeds the distance S, which is equal from geometrical considerations to l + l-sinof. Then, when the flap is folded over, it inevitably abuts against the transverse support element 7. Thus, 3 + + 1- sinrt, from where (1 - sinod.

The skirt should be inclined to the axis of the forging at an angle within oi 85 °. At smaller angles in the process of folding, there are observed breaks of sunshine, and sometimes the loss of its stability in the form of buckling or premature separation of the forging, which reduces the effect of quality improvement, and at large values of the magnitude of compressive stresses from constrained bending, do not reach values sufficient for a noticeable increase in the quality of shit.

Since the angle of inclination influences the stamping force and the filling of the die cavity, i.e. may be independently optimized during punching and beyond the limits set above, in the latter case it is necessary to cut the surface of the trimmed matrix, which is pressed against the breaks, to be convex toward the oblo (Fig. 4, left) at an angle of inclination / generatrix to the axis, satisfies the condition of Ј / 3 40 °, which reduces the amount of subsequent bending of the hollow during separation to acceptable limits (Fig. 4, right). In this case, from the above considerations, in order to ensure effective separation, it is necessary that the difference in the angles of inclination of the generatrix surface of the matrix and the billet to the axis satisfy the condition 5 ° / L-o / ISO0.

Example. Barrel-shaped articles were obtained, similar to those shown in FIG. 3 (right), which had a diameter of the upper and lower bases 55–20 mm, and the largest diameter of the middle part — 25 mm with a total height of 30 mm. Investigated the workpiece from the following materials: steel 10, aluminum

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AB alloy and copper M 1. For comparison, the preparation was carried out using the basic method, which is the prototype.

According to the basic method, according to which a burr was obtained without inclination to the axis, i.e. perpendicular to the n after separation, the surface cleanliness of the site of separation did not exceed 3 square meters, and gaps were observed on the AB alloy product. Such a surface required further refinement. When stamping, a burr was obtained with a maximum width of 10 mm and a thickness of 1 mm.

According to the invention, the angle of inclination was chosen (75 °. For 1 10 mm, according to the proposed ratio, it was found that L GO, 34 mm. We chose J 0.2 mm, since the smaller L, the greater the transverse backwater and, accordingly, Cleaner cut surface. After trimming around

but, that the cleanness of the cut surface for steel products 10 corresponded to 7 quality, and for products from AB and HZ - 6 quality and was not worse than the cleanliness of the other stamped surfaces, i.e. did not need to be improved.

When d 86 ° was chosen, it was established that out of ten pieces of products from each material, only four pieces of steel 10 had a cut-off surface that corresponded to 4 kvalitet, out of Ml - only three pieces, and from AB - only two pieces. For the remaining products, the purity of the cut corresponded to 3 quality, i.e. this angle is not sufficient to provide a significant effect compared to the base method. When ol 85 ° was chosen, the cut quality of all products improved to 5 kVa. When choosing / 49 ° for steel products 10, a break in the deflection stage began to be observed, and for products from AB and Ml, this breakup occurred. As a result, the quality of the cut surface did not exceed 4 qualities. Therefore, a matrix with a convex surface having an angle was used for these products. As a result, the purity of the cut for all products is equal to -1 to 6-7 qualifications.

Thus, as compared with the base object, the invention significantly improves the quality and reduces the labor intensity by increasing the purity of the separation.

Claims (5)

1. A method of producing stamped products, including stamping of a forging to form a bur and its subsequent separation by a punch in a cut matrix, characterized in that, in order to improve quality and reduce labor intensity by increasing the purity of the separation surface, a burr is formed at an angle to the forging axis, before separating the scrap from the forgings, is placed in the trimming matrix. With the abutment of the butt block into it, forming an acute angle to the axis of the forging, and the splitting is performed by bending it with a punch with a cross at least part of its working stroke and trimming on the remaining part of the working stroke of the punch. 2. The method according to claim 1, about tl and h a yu and with the fact that the burrs are formed with an angle to the axis of the forging 50 ... 85. 3. Method according to paragraphs. 1 and 2, that is, the forging with a burr is placed in a trimming matrix with the formation of a gap L between the lateral surface of the burr and the element of the transverse matrix support selected from the condition L 1 x (1 - sino O, where 1 is the greatest width; of - the angle of inclination of the hollow to the axis of the forging. 4. Method according to claim, characterized in that the quiescent is placed on the matrix with the surface convex in the direction of the punch with the angle 3 of the generator forming pressure to the axis, satisfying the condition of 5 ° / 3 90Г. 5. Method according to paragraphs. 1 and 4, characterized in that the difference in the angles of inclination of the support surface 55 of the matrix and the pressure axis satisfies the condition 5 Ј p, - of. 30. t  ///// Phie. FIG. 2 FIG 4