JPH0723084Y2 - Material holding device in the forging process - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a material holding device used for centering and holding a material introduced into a material inlet of a die in a forging process, particularly an upsetting process.

(Prior Art) Conventionally, a material that has been put into a material input port of a die is pressed from above by a punch having a diameter smaller than that, and the material is pressed into a cup shape in the die. Thus, a plurality of sliding members that are urged toward the center of the material feeding port are radially arranged on the upper surface of the die, and the sliding members contact the outer peripheral surface of the material fed into the loading port. It is known that each holding piece which is in contact with the holding piece is attached and the material is centered and held by these holding pieces.

In this product, the holding piece is composed of a link piece that is pivotally attached to the sliding member so that it can tilt upwards against the spring, and the material held between the holding pieces is pressed down into the die by a punch to form the insert. After that, when the punch is raised and the product is extruded from the die by the knockout pin, the holding piece is pushed by the product and tilts upward, and the reaction thereof corrects the posture at the time of extruding the product. .

(Problems to be solved by the invention) In the above, since the punch has a diameter smaller than the material diameter, when the punch descends, interference between the punch and the holding piece does not occur, but a punch larger than the material diameter is used. When the upsetting is performed by using the punch, the punch interferes with the holding piece. In this case, the sliding member is allowed to recede radially outward by a cylinder or the like, and the sliding member is moved before the punch lowers to the holding piece arrangement level after the punch comes into contact with the material and the forming is started. It is possible to retract the holding piece from the punch by retracting it outward, but it is practical to retract the holding piece within a short time from the start of molding until the punch falls to the placement level of the holding piece. It is difficult, and even if the retracting operation is possible, the structure becomes complicated and the cost becomes high.

In view of the above points, the present invention aims to provide a material holding device having a simple structure suitable for upsetting.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a plurality of sliding members radially urged toward the center of the input port are radially provided on the upper surface of the die having the material input port. In the device for disposing the holding members that come into contact with the outer peripheral surface of the material to be put into the charging port to these sliding members and center and hold the material by these holding pieces, Each of the sliding members is composed of a leaf spring that can be bent in the vertical direction extending inward in the radial direction.

(Function) The material put into the material input port is centered and held by a plurality of holding pieces attached to a plurality of sliding members, and the material is expanded by the compression of the material as the material is formed by the punch descending. When the diameter is increased, the holding piece is pushed by the material and recedes outward in the radial direction against the biasing force of the sliding member, and then when the punch is lowered to the arrangement level of the holding piece, the punch is placed on the upper surface of the tip of the holding piece. However, since the holding piece is composed of a leaf spring that can be bent in the vertical direction, the holding piece bends downward and recedes outward in the radial direction due to the downward movement of the punch. The material is upset formed in the die by penetrating downward between the holding pieces.

When the product is extruded from the die after molding, the product is extruded while the holding piece that has returned to the forward position in the radial direction is deflected upward by the biasing force of the sliding member, and the product is extruded by the elasticity of the holding piece. The product's pushing posture is corrected.

(Example) In the illustrated example, the device of the present invention is applied to a press molding machine for upsetting, and the molding machine includes a lower die (1).
And a punch (2) on the upper side, and a material W having a diameter smaller than the inner diameter of the die, which is fed from above by a feeding device (not shown) into the material feeding port (3) formed in the die (1), Push up into the die (1) by a punch (2) having a diameter substantially equal to the inner diameter to perform upsetting, and after molding, push out the product from the die (1) with a knockout pin (4) provided at the bottom of the die (1). Is configured.

An annular mounting plate (5) is fixedly provided on the upper surface of the die (1) so as to surround the material input port (3), and the material mounting port (3) is mounted on the mounting plate (5) with respect to the material input port (3). A plurality of sliding members (6) were radially arranged. As shown in FIG. 3, each sliding member (6) is supported on a base (6a) fixed to a mounting plate (5) so as to be slidable in a radial direction via rollers (6b), A cushion member (7) incorporating a plunger (7b), which is biased radially inward by a spring (7a), as shown in the fourth illustration, is provided radially outward of the arrangement portion of the sliding member (6). The holder (7c) fixed to the mounting plate (5) is screwed into the holder (7c), the plunger (7b) is brought into contact with the sliding member (6), and the sliding member (6) is moved to the inlet (3). ), And the stopper bolt (6b) fixed to the sliding member (6) normally abuts the stopper bolt (6c) fixed to the base (6a). The sliding member (6) is held at the forward position of (3).

Each of the sliding members (6) is provided with a holding piece (8) made of a leaf spring which can extend inward in the radial direction and which can be bent in the vertical direction, and the position of which can be adjusted in the radial direction in a long hole (8a) at the tail end. It is bolted, and in the illustrated embodiment, the leaf spring is folded back to form the holding piece (8) having an upper and lower double plate structure in order to increase the bending rigidity of the holding piece (8), but the present invention is not limited to this. Of course, it is not a thing.

According to the above configuration, the material W introduced into the material introduction port (3) is centered and held between the plurality of holding pieces (8) to prevent its fall, and then the punch (2) is lowered. When the forming of the material W is started, the holding piece (8) is pushed by the material W due to the diameter expansion accompanying the compression of the material W, and the radial direction is resisted against the urging force of the cushion member (7). The punch (2) then retreats outward, the punch (2) then contacts the upper surface of the tip of the holding piece (8), and as shown in FIG. 6, the holding piece (8) retreats outward while flexing downward. Each time, the lower end of the punch (2) penetrates downward between the holding pieces (8), and the upsetting of the material W is performed in the die (1) as shown in FIG.

When the punch (2) is lifted after forming, the holding piece (8) returns to the forward position inward in the radial direction via the sliding member (6) by the urging force of the cushion member (7), and then the knockout pin. When (4) is raised, the product W'is extruded from the die (1) while bending the holding piece (8) upward as shown by the phantom line in FIG. Penetrates between the holding pieces (8), the product W'is held in a predetermined posture between the holding pieces (8) as shown by the solid line in the figure, and the product W'is taken out by a take-out device (not shown) to perform the next step. Be transported to.

Although the embodiment in which the device of the present invention is applied to the press molding machine for upset molding has been described above, it is of course possible to apply the device of the present invention to a press molding machine for push molding.

(Effects of the Invention) As is clear from the above description, according to the present invention, the material can be centered and held from the time of charging to the time of starting molding, and molding can be performed without uneven thickness, The posture of the product at the time of extrusion can be corrected, and the interference between the punch and the holding piece at the time of upsetting using a punch larger than the material diameter can also be prevented, and the structure is only composed of the leaf spring. It is sufficient and has the effect that the structure is simple and can be obtained at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cutaway side view of an example of a press molding machine equipped with the device of the present invention, FIG. 2 is a plan view thereof, and FIGS. 3 and 4 are III- of FIG. 2, respectively. An enlarged cross-sectional view taken along line III and IV-IV, and FIGS. 5 to 8 are views for explaining the operation. (1) …… Die, (3) …… Material input port (6) …… Sliding member, (8) …… Holding piece

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Shou 63-53337 (JP, U) Sui 60-600039 (JP, U) Sui 62-35544 (JP, Y2)

Claims (1)

[Scope of utility model registration request] 1. A plurality of sliding members that are urged toward the center of the charging port are radially arranged on the upper surface of a die having a material charging port, and these sliding members are charged into the charging port. In a device that attaches each holding piece that comes into contact with the outer peripheral surface of a material to be held and centers and holds the material by these holding pieces, each holding piece is curved in a vertical direction extending radially inward from each sliding member. A material holding device in a forging process, which is composed of a possible leaf spring.