JP2009148773A - Die for die-casting and die-casting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a die for die-casting and a die-casting method, which allow molten metal flow approximately equally into the upper part side and the lower part side of a cavity. <P>SOLUTION: A base-end side bar-like part 42 of a flow divider 40 is positioned in a flow divider inserting through-hole 30b and in a cavity 31. A front end part 41 is arranged extending from the cavity 31 into a first runner part 21 through a gate 21a. An upper part 41A of the tapered surface of the front end part 41 of the flow divider 40, which is formed in an approximately truncated-conical shape, is arranged close to an upper part 21A of the internal circumferential surface of an intermediate die 20, which demarcates the first runner part 21. The distance between the upper part 41A of the tapered surface of the front end part 41 and the upper part 21A of the internal circumferential surface of the intermediate die 20, which demarcates the first runner part 21, is shorter than the distance between the part other than the upper part 41A of the tapered surface of the front end part 41 and the part other than the upper part 21A of the internal circumferential surface of the intermediate die 20, which demarcates the first runner part 21. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a die-casting die and a die-casting method, and more particularly to a die-casting die used for a horizontal injection / horizontal clamping type die casting machine and a die-casting method performed using the die-casting die.

  A mold is known in which a runner, a gate, and a cavity are formed, and the melt is filled into the cavity through the runner and the gate. Biscuits are formed at one end of the runner, and one end of the sleeve is opened to face the biscuit. A plunger tip is provided in the sleeve so as to be movable in the axial direction of the sleeve. By driving the plunger tip, molten metal such as aluminum alloy injected into the sleeve is filled into the cavity through the biscuits, runners, and gates. A mold having such a structure and having a center gate structure in which a gate is disposed substantially at the center of a cavity is conventionally known.

Japanese Patent Application Laid-Open No. 2006-103577 (Patent Document 1) discloses a metal for vertical casting having a center gate structure which is used in a gravity casting method or a low pressure casting method to form a wheel material such as a road wheel for an automobile. The type is described. In the vertical casting mold having such a center gate structure, the cavity for forming the wheel material is formed in a substantially horizontal circle around the gate, and is formed at the upper end of the runner extending from vertically below. Connected through gates. In order to allow the molten metal flowing from the gate to the cavity to be uniformly dispersed and flowed into the cavity, a diverter having a substantially truncated cone shape extending from the cavity side to the runner through the gate at the center position of the gate. Is provided.
JP 2006-103577 A

  However, when the above-mentioned center gate structure is applied to a die casting die used in a horizontal injection / horizontal clamping type die casting machine, the molten metal flowing from the gate to the cavity is substantially truncated at the center of the gate. In spite of the provision of the conical diverter, a large amount of molten metal flows into the upper part of the cavity and the molten metal flows into the lower part of the cavity, resulting in a problem of poor circulation of the hot water toward the lower part of the cavity.

  Therefore, an object of the present invention is to provide a die casting mold and a die casting method in which a molten metal flows into the upper side and the lower side of a cavity substantially evenly.

  In order to achieve the above object, the present invention cooperates with the first mold parts 10 and 20 in which runners 11 and 21 having one end forming a gate 21 a are formed, and the first mold parts 10 and 20. And a second mold part 30 defining a cavity 31 connected to the runner 21 via the gate 21a, the gate 21a being disposed at a substantially central position of the cavity 31, 11, 21 and a die-casting mold 1 in which molten metal is filled into the cavity 31 through the gate 21a, which is provided in the second mold part 30 and enters the runner 21 from the cavity 31 side through the gate 21a. A diverter 40 extending, and the diverter 40 is disposed in the runner 21 close to a part 21A of the inner peripheral surface of the first mold part 20 defining the runner 21; Current divider 40 and the inside The distance between the part 21A of the surface provides a short die-casting die 1 than the distance between the portions other than the portion 21A of 該分 commutator 40 and the inner peripheral surface.

  Here, the runner is connected to the first runner portion 21 having a substantially straight shape and one end forming the gate 21a, and the other end of the first runner portion 21, and downward from the other end of the first runner portion 21. A second runner portion 11 that extends, and the part of the inner peripheral surface is composed of an upper portion 21A of the inner peripheral surface of the first mold portion 20 that defines the first runner portion 21. Is preferred.

  In addition, the present invention provides a die casting method in which die casting is performed using the die casting mold 1 according to claim 1 or 2.

  According to the die-casting die of claim 1 of the present invention and the die-casting method of claim 3, the die-casting method is provided with a diverter provided in the second die portion and extending from the cavity side through the gate into the runner. Is arranged close to a part of the inner peripheral surface of the first mold part defining the runner in the runner, and the distance between the diverter and a part of the inner peripheral surface is the distance between the shunt and the inner peripheral surface. Since it is shorter than the distance from other parts than the part, it is possible to reduce the amount of the molten metal flowing between the current divider and a part of the inner peripheral surface. The momentum of the molten metal flowing between the parts can be improved. For this reason, the molten metal flowing into the cavity from the gate can be made substantially uniform in the cavity.

  In addition, by changing the position of the flow divider in the runner, it is possible to make the molten metal flowing into the cavity uniform, so it is not necessary to change the shape of the runner and the gate, and the molten metal flowing into the cavity. Uniformity of the surroundings can be realized relatively easily.

  Moreover, according to the die-casting die according to claim 2 and the die-casting method according to claim 3, the runner is connected to the first runner portion having a substantially straight shape and one end forming a gate, and the other end of the first runner portion. And a second runner portion extending downward from the other end of the first runner portion, and a part of the inner peripheral surface is from an upper portion of the inner peripheral surface of the first mold portion defining the first runner portion. Therefore, the molten metal that has flowed upward from below through the second runner part vigorously flows on the upper part of the inner peripheral surface of the first mold part that defines the first runner part and flows into the upper part of the cavity. Therefore, it is possible to prevent the hot water from flowing to the lower part of the cavity from being deteriorated.

  A die casting mold according to an embodiment of the present invention will be described with reference to FIGS. The die casting mold 1 is for casting a road wheel of a circular vehicle or the like, and is attached to a side injection / horizontal clamping type die casting machine. As shown in FIG. 1, the die casting mold 1 has a fixed mold 10, an intermediate mold 20, and a movable mold 30. The fixed mold 10 has a fixed mold dividing surface 10A that faces the intermediate mold 20 and can abut on an intermediate mold first divided surface 20A described later. The fixed mold dividing surface 10A is directed in the vertical direction in FIG. ing. Here, the vertical direction in FIG. 1 matches the vertical vertical direction, and the horizontal direction in FIG. 1 matches the horizontal direction. A fixed mold recess 10a made of a recess is formed in the fixed mold 10 at the position of the fixed mold dividing surface 10A, and the second runner portion 11 is defined by the fixed mold recess 10a as described later. As shown in FIG. 1, the second runner portion 11 is formed so as to be oriented in a substantially vertical direction.

  One end of a sleeve 12 is opened at the lower end portion of the second runner portion 11 in the lower portion of the fixed mold 10 shown in FIG. The sleeve 12 has a substantially cylindrical shape, and a hot water supply hole (not shown) including a through hole that communicates the inside and the outside of the sleeve 12 is formed at a position near the other end (not shown) of the sleeve 12. The molten metal can be supplied into the sleeve 12 (not shown) from the hot water supply hole. Further, a plunger (not shown) is provided at a portion near the other end (not shown) of the sleeve 12. A plunger (not shown) is slidable in the sleeve 12, and after the molten metal is supplied into the sleeve 12 from a hot water supply hole (not shown), the plunger (not shown) is advanced to move the molten metal in the sleeve 12 to the second. The cavity 31 can be filled through the runner portion 11, the first runner portion 21 described later, and the gate 21a.

  The intermediate mold 20 includes an intermediate mold first divided surface 20A that faces the fixed mold 10 and can contact the fixed mold dividing surface 10A, and an intermediate mold that faces the movable mold 30 and can contact a movable mold dividing surface 30A described later. The second divided surface 20B is oriented in the vertical direction of FIG. A first runner that extends in a substantially straight line in a substantially horizontal direction at the position of the intermediate mold 20 that faces the upper end of the second runner portion 11 when the intermediate mold 20 is in contact with the fixed mold 10 as will be described later. A portion 21 is formed. The first runner portion 21 has a tapered shape that decreases in diameter from one end to the other end, and one end of the first runner portion 21 is in the vertical direction when the intermediate die 20 is in contact with the movable die 30. The gate 21a is formed opposite to the central position of the cavity 31. The other end of the first runner portion 21 is connected to the upper end of the second runner portion 11 when the intermediate die 20 is in contact with the fixed die 10. The 1st runner part 21 and the 2nd runner part 11 constitute a runner. The fixed mold 10 and the intermediate mold 20 correspond to a first mold part.

  The movable mold 30 has a movable mold dividing surface 30A that faces the intermediate mold 20 and can be brought into contact with the intermediate mold second dividing surface 20B. The movable mold dividing surface 30A is oriented in the vertical direction in FIG. . A movable mold recess 30a made of a recess is formed in the movable mold 30 at the position of the movable mold dividing surface 30A, and a cavity 31 is defined by the movable mold recess 30a as described later. The movable mold 30 is movable in a substantially horizontal direction, that is, in the left-right direction in FIG. 1 so as to move away from and approach the intermediate mold 20 fixed to the fixed mold 10, and abuts against the intermediate mold 20. Is possible. The movable mold 30 corresponds to a second mold part.

  When the intermediate mold 20 is in contact with the fixed mold 10 by the fixed mold dividing surface 10A and the intermediate mold first dividing surface 20A being in contact with each other, the second runner portion 11 is formed by the intermediate mold 20 and the fixed mold 10. Defined. Further, when the movable mold dividing surface 30 </ b> A and the intermediate mold second dividing surface 20 </ b> B are in contact with each other, the cavity 31 is defined by the intermediate mold 20 and the movable mold 30 when the movable mold 30 is in contact with the intermediate mold 20. It is comprised so that it may be made. The cavity 31 is connected so as to communicate with the first runner portion 21 via the gate 21a.

  The movable mold 30 is formed with a diverter insertion through hole 30b. The diverter insertion through-hole 30b penetrates the movable mold 30 so as to connect the movable mold dividing surface 30A and the side opposite to the side where the movable mold dividing surface 30A is provided. One end of the diverter insertion through-hole 30b is opened at a center position of the cavity 31 and facing the gate 21a, and the other end has a diameter-expanded opening 30c that expands, and part of the diameter-expanded opening 30c. A recess 30d is formed in which a rotation stopper 44 described later can be engaged.

  A substantially rod-shaped flow divider 40 is inserted into the flow divider insertion through hole 30b. The diverter 40 has a distal end portion 41 and a proximal end side rod-like portion 42 that are integrally formed, and the proximal end side rod-like portion 42 is located in the diverter insertion through hole 30b and in the cavity 31, The distal end portion 41 is arranged to extend from the cavity 31 into the first runner portion 21 through the gate 21a. An enlarged diameter portion 43 is provided at the proximal end portion, and the enlarged diameter portion 43 is engaged with the enlarged diameter opening 30c. The enlarged diameter portion 43 is provided with a rotation stopper 44 protruding from the peripheral surface of the enlarged diameter portion 43. The rotation stopper 44 engages with the recess 30d so that the diverter 40 does not rotate about its axis. It is configured. Further, the base end of the diverter 40 is in contact with a holder 30-2 provided in the movable mold 30 and prevents the diverter 40 from coming off from the diverter insertion through hole 30b.

  The tip portion 41 of the diverter 40 has a substantially truncated cone shape that is tapered as shown in FIG. An upper portion 41A of the tapered surface of the tip portion 41 having a substantially truncated cone shape is disposed close to the upper portion 21A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21, as shown in FIG. The distance between the upper portion 41A of the tapered surface of the tip portion 41 having a substantially truncated cone shape and the upper portion 21A of the inner peripheral surface of the intermediate mold 20 defining the first runner portion 21 is substantially truncated. The distance between the portion other than the upper portion 41 </ b> A of the tapered surface of the tip portion 41 having a conical shape and the portion other than the upper portion 21 </ b> A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21 is shorter.

  A step portion 40 </ b> A is provided at a connection position between the distal end portion 41 of the diverter 40 and the proximal end side rod-shaped portion 42. As shown in FIG. 1, the step portion 40A is provided so as to be lowered one step downward. The cast product cast in the cavity 31 has a through-hole having a diameter larger than that of the base-side rod-like portion 42 around the axis center of the base-side rod-like portion 42 of the flow divider 40 by post-processing. However, since the stepped portion 40A is provided, the portion of the machining allowance that is scraped off by post-processing for forming such a through hole can be reduced. The step portion 40 </ b> A is disposed in the cavity 31.

  More specifically, the portion of the base end side rod-shaped portion 42 on the right side shown in FIG. 1 is more than the portion of the stepped portion 40A, and the portion of the base end side rod-like portion of the flow divider 40 shown in FIG. The shape seen in the direction perpendicular to the axial direction of 42 is circular. As shown in FIG. 2, the tip 41 </ b> B of the diverter 40 has two radii of two straight lines having the same length in the vertical direction in FIGS. It is shaped like an arc. Here, the value of the radius of the arc connecting the upper ends is larger than the value of the radius of the arc connecting the lower ends. The portion from the portion on the left side shown in FIG. 1 to the tip 41B of the stepped portion 40A has a shape as viewed in the direction perpendicular to the axial direction of the proximal-side rod-like portion 42 of the flow divider 40 from the tip 41B. A tapered surface as shown in FIG. 1 is formed so that the shape of the tip 41B gradually increases in a similar shape toward the stepped portion 40A.

  The upper surface 41A having a larger radius of the arc than the lower portion of the taper surface thus expanded has a circular shape when viewed in a direction perpendicular to the axial direction of the proximal end side rod-shaped portion 42 of the diverter 40. It is a peripheral surface and is disposed close to the upper portion 21 </ b> A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21. Therefore, also in the gate 21a, the upper portion 41A of the tapered surface is arranged close to the upper portion of the gate 21a in which the shape viewed in the direction perpendicular to the axial direction of the proximal end side rod-like portion 42 of the shunt 40 is circular. Has been. A cooling flow path (not shown) through which cooling water can flow from the base end side rod-like portion 42 to the distal end portion 41 is formed inside the diverter 40, and the cooling water is supplied into the cooling flow passage (not shown). The current divider 40 can be cooled by flowing it.

  Further, the movable die 30 is provided with an unillustrated extrusion pin that can protrude into the cavity 31. By moving the extrusion pin (not illustrated) forward with respect to the cast product solidified in the cavity 31, it will be described later. In addition, the cast product can be removed from the movable mold 30.

  In the die casting method, first, the intermediate mold first dividing surface 20A is brought into contact with the fixed mold dividing surface 10A of the die casting mold 1 in a state where the mold is opened, and the intermediate mold 20 is set on the fixed mold 10, and the second runner portion. 11 and the 2nd runner part 11 and the 1st runner part 21 are connected, and a runner is defined. Next, the movable mold 30 is moved in the direction of the intermediate mold 20 and the fixed mold 10, that is, in the left direction in FIG. 1, and as shown in FIG. 1, the movable mold dividing surface 30A is moved to the intermediate mold second divided surface. The cavity 31 is brought into contact with 20B to define the cavity 31, and the cavity 31 is communicated with the first runner portion 21 through the gate 21a.

  At this time, the diverter 40 moves in the direction of the fixed mold 10 integrally with the movable mold 30 and extends into the first runner portion 21. In the first runner portion 21, the upper portion 41 A of the tapered surface of the tip portion 41 is disposed close to the upper portion 21 A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21, and the tip of the diverter 40 The distance between the upper portion 41A of the tapered surface of the portion 41 and the upper portion 21A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21 is the upper portion of the tapered surface of the tip portion 41 having a substantially truncated cone shape. The distance between the portion other than 41A and the portion other than the upper portion 21A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21 is shorter.

  Next, the molten metal is supplied into the sleeve 12 from a hot water supply hole (not shown). Then, a plunger (not shown) is slid in the sleeve 12 to fill the molten metal in the sleeve 12 into the cavity 31 through the second runner portion 11, the first runner portion 21, and the gate 21a. At this time, the molten metal that has flowed vigorously in the second runner portion 11 from vertically downward to upward tends to vigorously flow into the cavity 31 along the upper portion of the first runner portion 21. An upper portion 41A of the tapered surface of the distal end portion 41 is disposed close to an upper portion 21A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21, and the upper portion 41A of the tapered surface of the distal end portion 41 and the first upper portion 41A are arranged. The distance from the upper portion 21A of the inner peripheral surface of the intermediate mold 20 that defines the runner portion 21 is such that the portion other than the upper portion 41A of the tapered surface of the tip portion 41 having a substantially truncated cone shape and the first runner portion 21 are arranged. Since it is shorter than the distance between the inner peripheral surface of the intermediate mold 20 other than the upper portion 21A, the amount of the molten metal flowing between the flow divider 40 and the upper portion 21A of the inner peripheral surface of the intermediate mold 20 is reduced. The upper part of shunt 40 and inner peripheral surface It is possible to improve the flow of the molten metal flowing between the portion other than 1A. Therefore, the molten metal flowing from the gate 21a in the cavity 31 can be made substantially uniform, and it is possible to prevent the molten metal flowing to the lower part of the cavity 31 from being deteriorated.

  Further, in the first runner portion 21, the upper portion 41A of the tapered surface of the tip portion 41 of the flow divider 40 is disposed close to the upper portion 21A of the inner peripheral surface of the intermediate mold 20 that defines the first runner portion 21. Since the molten metal flowing into the cavity 31 can be made uniform, the shape of the first runner portion 21 and the gate 21a is not changed, and the molten metal flowing into the cavity 31 is made uniform. It can be realized relatively easily.

  Next, the molten metal in the cavity 31 is cooled and solidified, and then the intermediate mold 20 and the movable mold 30 are moved to the right in FIG. At the connection position between the part 21 and the second runner part 11, the molten metal solidified in the runner is cut along the intermediate first divided surface 20A. Next, the movable mold 30 is moved relative to the intermediate mold 20 and separated from the intermediate mold 20. At this time, the molten metal portion solidified in the cavity 31 and the molten metal portion solidified in the first runner portion 21 are separated from the intermediate die 20 while being integrally attached to the movable die 30.

  Next, an unillustrated extrusion pin provided on the movable die 30 is advanced to extrude the molten metal portion solidified in the cavity 31 and the molten metal portion solidified in the first runner portion 21 and removed from the movable die 30. . The above is the die casting method. Then, the removed cast product is post-processed to remove unnecessary cutting allowances. For example, a through-hole having a diameter larger than that of the base end side rod-shaped portion 42 is formed at the center position of the casting product around the axial center of the base end side rod-shaped portion 42 of the shunt 40 and attached to this portion. The taper-shaped portion, that is, the molten metal portion solidified in the first runner portion 21 is removed.

  The die-casting die and the die-casting method according to the present invention are not limited to the above-described embodiments, and various modifications and improvements can be made within the scope described in the claims. For example, in the present embodiment, the die casting mold 1 is for casting a circular wheel, but is not limited to a road wheel. Therefore, each shape of the die casting mold such as the shape of the cavity is not limited to each shape of the die casting mold 1 according to the present embodiment.

  Further, one end of the first runner portion 21 is opposed to the central position of the cavity 31 in the vertical direction when the intermediate mold 20 is in contact with the movable mold 30, and forms a gate 21a. A gate may be formed facing the substantially central position of the cavity.

  The die-casting die and the die-casting method of the present invention are extremely useful in the field of die-casting die that requires the molten metal to flow approximately evenly into the upper and lower sides of the cavity.

The principal part sectional drawing which shows the die-casting die by embodiment of this invention. Explanatory drawing which shows the diverter provided in the die-casting die by embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Die casting metal mold | die 10 Fixed mold | type 11 2nd runner part 20 Intermediate mold | type 21 1st runner part 21A Upper part 21a of inner peripheral surface Gate 30 Movable type | mold 31 Cavity 40 Shunt element 41A Upper part of a taper surface

Claims (3)

A first mold part formed with a runner whose one end forms a gate;
In cooperation with the first mold part, comprising a second mold part defining a cavity connected to the runner via the gate;
The gate is a die-casting die disposed at a substantially central position of the cavity and filled with molten metal into the cavity through the runner and the gate;
A diverter provided in the second mold portion and extending from the cavity side through the gate into the runner, wherein the diverter defines the runner in the runner The distance between the current divider and the part of the inner peripheral surface is the distance between the current divider and the other part other than the part of the inner peripheral surface. Die casting mold characterized by being shorter than the distance. The runner includes a first runner portion having a substantially straight shape and one end forming the gate, and a second runner portion connected to the other end of the first runner portion and extending downward from the other end of the first runner portion. And
2. The die casting mold according to claim 1, wherein the part of the inner peripheral surface is composed of an upper portion of the inner peripheral surface of the first mold part that defines the first runner part.   3. A die casting method, wherein die casting is performed using the die casting mold according to claim 1.

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