JPH0578357U - Cast pin device for casting - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent the galling of the casting pin with a small draft, and to make the temperature of the casting pin uniform during casting as a whole to greatly reduce the incidence of product defects. In the casting pin device for casting, a casting pin having a circular cross section that forms a cavity space together with a movable die and a fixed die is moved in and out by a hydraulic cylinder. In such a device, the cast pin is rotatably attached to the cylinder rod. Further, a fixed cylinder is arranged around the cast pin, and a rotation guide mechanism is provided between the fixed cylinder and the cast pin. This is accomplished by forming a guide groove on the inner peripheral surface of the cylindrical body and providing a guide pin on the side of the cast pin. As the casting pin is extruded, the casting pin itself is rotated and loaded into the cavity.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a casting pin device for casting, and relates to improvement of a casting pin device used for forming a casting hole in a product at the time of casting in order to prevent internal defects and reduce machining.

[0002]

[Prior Art]

 Conventionally, when casting a product by a molten metal forging method, a die casting method, a gravity method, etc., it is generally performed to form a casting hole in the product for the purpose of preventing defects in the product and reducing the machining process. .. The casting pin is usually set in a movable mold and is configured to move in and out of the cavity along the movable mold. The operation of moving in and out is performed by a hydraulic cylinder mechanism, and when clamping the mold, the hydraulic cylinder pushes it out into the cavity, and after molding, it is pulled out from the cavity. In order to make it easier to pull out the die when releasing the die from the product, the die is generally provided with a draft and a mold or release agent is applied. Is.

However, in the conventional die-cast pin device, since the die-cast pin is set to the movable die, it is difficult to attach the coating die to the entire outer peripheral surface of the die-cast pin, and therefore the pin Since there is a high rate that galling will occur in the product and lead to product defects, a method has been adopted to prevent galling by increasing the pulling out ratio of the casting pin. The conventional draft angle is generally 2 ° 30 ′ to 3 °.

[0004]

[Problems to be solved by the device]

 However, increasing the draft angle is not preferable because it leads to an increase in machining such as cutting in the subsequent process. In addition, the casting pin is moved in and out of the cavity along with the movable mold, but since the facing part to the pouring port usually provided in the fixed mold is constant, the one-sided heating state due to pouring does not occur. Occurrence may occur, the temperature of the casting pin may not be uniform, and a temperature difference may occur. Due to this temperature difference, the solidification rate of the molten metal is not uniform around the casting pin, and there is a risk of internal defects in the product due to delay in solidification.

The object of the present invention is to pay attention to the above-mentioned conventional problems, and to prevent the galling of the casting pin with a small draft, and to make the temperature of the casting pin uniform during casting as a whole to prevent product defects. An object of the present invention is to provide a die-cast pin device for casting, which can reduce the occurrence rate significantly.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, a casting pin device for casting according to the present invention is a casting pin device for casting, wherein a casting pin that forms a cavity space with a movable die and a fixed die is moved in and out by a cylinder. The casting pin is rotatably attached to the rod of the cylinder, a fixed cylinder is placed around the casting pin, and a rotation guide mechanism is provided between the fixed cylinder and the casting pin to set the axial direction of the casting pin. The cast pin is configured to rotate with the movement of the.

[0007]

[Action]

 According to the above configuration, when the casting pin is pushed in, the casting pin rotates and is inserted into the cavity formed by the movable mold and the fixed mold, and the cavity space that imitates the product shape is similarly formed. Form. A mold is attached to the casting pin during this mold clamping.However, since the casting pin rotates during the operation of attaching the mold, even if the coating of the mold is performed from one direction, It is possible to attach the coating type to the entire peripheral surface. As a result, since the mold release ensures the mold release, it is not necessary to take a large draft. Moreover, the facing portion of the casting pin to the pouring port can be changed at any time for each shot by appropriately setting the rotation amount of the casting pin, which prevents local heating of the casting pin. Therefore, it is possible to effectively prevent a temperature difference from being generated on the outer peripheral surface of the casting pin, thereby making it possible to make the solidification rate of the molten metal around the casting pin uniform and suppress the occurrence of internal defects in the product due to the temperature difference. ..

[0008]

【Example】

 Hereinafter, a concrete embodiment of a casting pin device for casting according to the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a sectional view of a casting apparatus equipped with a casting pin device according to an embodiment. As shown in this figure, the casting device equipped with the casting pin device adopts the push-up casting method, in which the fixed mold 10 at the bottom is equipped with the molten metal pushing plunger 12 and the movable mold 14 at the top. It is configured so that the cavity 16 formed between them is pushed up and poured.

In such a casting apparatus, a casting pin device is incorporated in the movable die 14. That is, the gate-shaped support frame 18 is fixed to the side surface of the movable mold 14, and the pushing cylinder mechanism 20 is mounted on this. The cylinder rod 22 driven by the push-in cylinder mechanism 20 is set such that the moving direction is along the die-matching portion of the cavity 16 formed by the fixed die 10 and the movable die 14, and the tip of the rod 22 has the above-mentioned shape. A casting pin 24 that is inserted into the cavity 16 and determines the product shape is attached to both the molds 10 and 14. The casting pin 24 has a circular cross-section, and is pinched between the die body 10 and 14 and a pin body portion 30 having a circular cross section for forming a die hole 28 in the product 26 and sealing the cavity 16. It is composed of a die forming portion 32 having a diameter larger than that of the portion 30, and a rod connecting portion 36 in which a contact step surface 34 for contacting the outer surfaces of both the dies 10 and 14 is formed. The pin body 30 is provided with a draft angle θ for releasing.

In such a structure, the cast pin 24 is rotatably connected to the cylinder rod 22 about the axis of movement. That is, a short column block 40 fixed by a bolt 38 is provided at the front end of the cylinder rod 22, and a circular flange 42 is integrally attached to the tip end surface of the cylinder block 40 via a neck 44. Both of them have a circular cross section, and the diameter of the neck portion 44 is formed smaller than the diameter of the circular flange 42. On the other hand, the rod connecting portion 36 of the cast pin 24 is rotatably fitted to the circular flange 42 and the neck portion 44, and an inward flange 46 having an inner diameter adapted to the neck portion 44 is provided at the tip thereof. A circular slot 48 that fits the circular flange 42 is formed in the inner surface thereof. As a result, the casting pin 24 can rotate with respect to the cylinder rod 22 about its axis.

Further, the casting pin 24 is adapted to be rotated by a certain amount at the same time as it is axially moved when being pushed into the cavity 16. Therefore, a cylindrical body 50 is fixed to the support frame 18 so as to surround the cylinder rod 22 and the cast pin 24 connected to the cylinder rod 22. A rotation guide mechanism is provided between the cylindrical body 50 and the casting pin 24 so that the casting pin 24 is rotated as the casting pin 24 is extruded. This is composed of a guide pin 52 provided on the cast pin 24 side and a guide groove 54 formed on the inner peripheral surface of the cylindrical body 50. That is, a guide pin 52 is attached to one part of the outer peripheral surface of the rod connecting portion 36 of the cast pin 24 so as to be able to move in and out in the radial direction, and the rear end surface is elastically urged by a spring 56 to be attached to the inner wall surface of the cylindrical body 50. It is projected toward.

On the other hand, a guide groove 54, into which the guide pin 52 is fitted, is formed on the inner peripheral surface of the cylindrical body 50. As shown in FIG. 2, this is a straight line along the extruding direction of the casting pin 24. A plurality of guide grooves 54L are formed in a circumferential direction at regular intervals, and the oblique intersections are formed so as to bridge and connect the ends of the adjacent linear guide grooves 54L. It is composed of a guide groove 54S. As a result, the straight guide grooves 54L and the oblique guide grooves 54S are alternately connected, and one guide groove 54 that is continuous in a zigzag pattern is formed on the inner wall surface of the cylindrical body 50 (FIG. 2 (1)). ).

The both guide grooves 54 are set so that the depth changes along the longitudinal direction, and the straight guide groove 54L has a forward end (in the drawing) of the casting pin 24 as shown in FIG. 2B. The depth is gradually reduced from the right end side toward the retreat end, and a pin drop deep groove portion 56R is formed at the retreat end portion. When the guide pin 52 to be guided reaches this deep groove portion 56R, a straight line is formed. The guide groove 54L is prevented from moving back. Further, as shown in FIG. 2 (3), the oblique guide groove 54 is directed from the deep groove portion 56R of the straight guide groove 54L as a starting point toward the forward end (right end in the figure) of the casting pin 24. The depth is gradually reduced, and a pin drop deep groove portion 56F is formed at the forward end portion (connection portion with the adjacent straight guide groove 54L), and the guided pin 52 guided reaches this deep groove portion 56F. At the same time, the oblique guide grooves 54S are similarly prevented from moving back. The front pin drop deep groove portion 56F is set to be the starting point of the next linear guide groove 54L. That is, the deep groove portions 56R, 56F serve as a direction switching portion of the guided guide pin 52, and are guided along the straight guide groove 54L during the backward movement and along the oblique guide groove 54S during the forward movement. I am trying. As a result, the casting pin 24 moves while rotating by an amount corresponding to the inclination angle of the oblique guide groove 54S when moving forward, and returns without moving along the straight guide groove 54L when rotating backward. There is.

A mold spray nozzle 58 for wiping and attaching the mold to the surface of the pin body 30 when the casting pin 24 is advanced in the movable mold 14 and inserted into the cavity 16 is set. Is formed, and the coating die is attached to the pin body 30 in accordance with the set timing of the cast pin 24.

According to the casting pin device having such a configuration, the casting pin 24 is pulled out and pushed in by the movable die 14 by driving the cylinder mechanism 20. When the cast pin 24 is in the set state, the guide pin 52 provided on the cast pin 24 is initially located in the pin drop deep groove portion 56F formed especially at the forward end portion of the guide groove 54. When the casting pin 24 is pulled out from this state, the guide pin 52 moves while being guided by the linear guide groove 54L, and therefore the casting pin 24 moves backward without rotating. At the retracted end, the guide pin 52 is located in the pin drop deep groove 56R.

When the casting pin 24 is moved forward after the product 26 is taken out, the guide pin 52 cannot move to the straight guide groove 54L due to the step difference of the deep groove portion 56R, and moves along the oblique guide groove 54S. You will be guided to do so. As a result, the casting pin 24 advances while rotating, reaches the deep groove portion 56F at the forward end and stops rotating, and is set in the cavity 16 in this state. At the time of this forward movement, a mold is sprayed from the mold spray nozzle 58 onto the surface of the pin body 30 of the cast pin 24.

Because of this, the casting pin 24 rotates when moving in and out of the cavity 16, so that the coating mold can be attached to the entire circumferential surface of the casting nozzle 24 by a plurality of cycles. .. Therefore, the draft angle θ attached to the casting pin 24 can be reduced. In the embodiment, this draft angle θ can be set to 0 ° 30 'to 1 °. Further, since the casting pin 24 is rotated for each shot to change the facing portion to the pouring port, the temperature difference on the surface of the casting pin 24 can be reduced and uniformized. Therefore, the solidification rate of the molten metal can be made uniform to prevent the occurrence of internal defects in the product due to the delay in solidification, the product defect rate can be reduced, and the yield can be improved.

The rotation angle of the casting pin 24 can be arbitrarily set by changing the span of the linear guide groove 54L.

[0020]

[Effect of the device]

 As described above, in the casting melt casting pin device according to the present invention, the casting pin is rotatably attached to the cylinder rod, and the fixed cylinder is arranged around the casting pin. A rotation guide mechanism was installed between the die and the die pin to enable the die pin to rotate as the die pin is extruded, enabling the die to be attached to the entire circumference of the die pin. The effect is that the gradient can be set small, and the temperature of the casting pin during casting can be made uniform throughout, and the incidence of product defects can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram of a casting device including a casting pin device according to an embodiment.

FIG. 2 is a cross-sectional view of a cylindrical body that constitutes a rotation guide mechanism of a casting pin.

[Explanation of symbols]

 10 Fixed Type 12 Molten Metal Pushing Plunger 14 Movable Type 16 Cavity 18 Support Stand 20 Pushing Cylinder Mechanism 22 Cylinder Rod 24 Cast Pin 26 Product 28 Drilling Hole 30 Pin Body 32 Mold Forming Part 34 Abutting Step Surface 36 Rod Connecting Part 38 Bolt 40 Cylindrical block 42 Circular flange 44 Neck portion 46 Inward flange 48 Circular groove hole 50 Cylindrical body 52 Guide pin 54 Guide groove 54L Straight guide groove 54S Oblique guide groove 56R, 56F Pin drop deep groove 58 Coating spray nozzle

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[Procedure amendment]

[Submission date] May 8, 1992

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (1)

[Scope of utility model registration request] 1. A casting pin device for casting, wherein a casting pin that forms a cavity space together with a movable die and a fixed die is moved in and out by a cylinder. The casting pin is rotatably attached to a rod of the cylinder. A fixed tubular body is arranged around the casting cylinder, a rotation guide mechanism is provided between the fixed tubular body and the casting pin, and the casting pin rotates as the casting pin moves in the axial direction. Cast pin device for casting.