JPS6068150A - Die structure - Google Patents

Abstract

PURPOSE:To remove a vertical flash in a die opening stage and to reduce man- hour by providing a gap of a limited size between the vertical mating surfaces of a stationary die and a movable die and providing a space having an undercut communicating with the gap to either of the dies. CONSTITUTION:A gap 7 of 0.3-0.5mm. is provided between the vertical mating surfaces 5, 6 of a stationary die 1 and a movable die 2 when the dies consisting of the stationary die 1, the movable die 2 and a sliding die 3 are clamped and therefore the molten metal introduced into a product cavity 4 enters the gap 7 and forms a vertical flash 11 and also enters the space 8 provided to either of the die 1 or the die 2, thereby producing an undercut part 9 united to the flash 11. The undercut 9 remains to the die 1 or the die 2 when the dies are opened after casting and therefore the flash 11 is cut from the rough casting in the undercut 9 part.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a mold structure that allows easy removal of cast burrs.

[Prior art]

In die casting, mold casting, etc., when divided molds are used for casting operations, molten metal is usually inserted into the mating surfaces of the divided molds, creating flash.

Since this cast burr remains on the raw casting material after mold release, it is necessary to remove it by post-treatment.

Conventionally, such casting burrs are removed in a trimming press process. By the way, in this trimming press, cast burrs generated in the horizontal direction, so-called horizontal flash, can be removed relatively easily, but cast burrs generated in the vertical direction, so-called vertical flash, are oriented in the direction of the cutting edge of the rimming press. Since they are the same, they simply touch or are pushed and bent, but not sheared.

For this reason, in the past, as a countermeasure against such vertical burrs, vertical burrs have been removed by increasing the accuracy of mold matching to minimize the occurrence of vertical burrs, or by manual finishing such as sanding before or after trimming. However, all of these conventional methods require a large amount of man-hours and time, resulting in high costs.

[Object of the present invention]

The present invention was made in order to solve the problems of the prior art described above, and an object of the present invention is to provide a mold structure in which vertical bulges can be easily removed in a mold opening process.

[Configuration of the present invention]

According to the present invention, such an object is a mold structure consisting of a fixed mold and a movable mold defining a product cavity, and having a vertical mating surface on the mating surfaces of the fixed mold and the movable mold, comprising: 0.3~0゜5m on the vertical mating surface of fixed type and movable type
This is achieved by a mold structure in which a gap of +m is provided and a space having an undercut portion communicating with this gap is provided in either a fixed mold or a movable mold forming a vertical mating surface.

In the present invention, a small gap is actively provided in the vertical burr generation area, that is, at the end of the mold mating surfaces of the fixed mold and the movable mold that contact the product cavity. This gap is provided to ensure that vertical burrs are generated, but if the gap is too small, the generation of vertical burrs will not be ensured, and if it is too large, the vertical burrs will be sheared when the mold is closed. It may become difficult or cause defects in the product. A suitable gap size is 0.3 to 0.5 xva so that such problems do not occur and the object of the present invention can be achieved.

Further, a space having an undercut portion is provided in a fixed type or a movable type continuously with this gap. This space only needs to have a part of it that is undercut with respect to the mold release direction of the raw casting material, and its cross-sectional shape may be any suitable shape such as a triangle. Further, the undercut may be of any shape as long as it becomes a hindrance during demolding, and its shape may be uneven, triangular, or any other appropriate shape.

[Operation of the present invention]

In the mold structure according to the present invention, a gap of 0.3 to 0.5 mm is provided between the vertical mating surfaces of the fixed mold and the movable mold, so the molten metal introduced into the product cavity enters this gap. It becomes a vertical burr and also enters the space provided on either the fixed type or the movable type, creating an undercut portion that is integrated with the vertical burr. For this reason, when the mold is opened after casting, the undercut portion remains in the fixed mold or the movable mold, and the vertical burr is cut from the casting rough material at this undercut portion.

[Configuration of the present invention]

Therefore, the present invention has the following effects.

(b) The vertical burrs that are forcibly generated are cut from the raw casting material at the base of the burr when the mold is opened by the undercut throat section, so the material taken out from the mold has no vertical burrs, and the vertical burrs are removed. This eliminates the need for finishing. Therefore, the number of man-hours can be significantly reduced.

(b) Since the vertical burrs are removed using the mold opening force when the mold is opened, a special process for removing the vertical burrs is not required, and the vertical burrs are quickly removed.

(c) Unlike the conventional method, there is no need for strict mold matching accuracy, so mold manufacturing man-hours and costs can be reduced. In addition, maintainability is improved because the mold does not require strict precision.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

(First Embodiment) FIG. 1 is a sectional view of main parts showing the mold structure according to the first embodiment of the present invention, and FIG. FIG. 2 is a cross-sectional view of main parts showing the state when the mold is opened after casting.

As shown in FIG. 1, the mold in the first embodiment consists of a fixed mold 1, a movable mold 2, and a slide mold 3 (a type of movable mold). With this fixed mold 1, movable mold 2, and sliding mold 3,
A product cavity 4 is defined. This mold is fixed type 1
The movable mold 2 has a vertical mating surface 5.6 as a mating surface. A gap 7 of 0.4 mm is provided at the portion of this vertical mating surface 5.6 that contacts the product cavity 4.

Further, a space 8 having a substantially triangular cross section that spreads out from this gap 7 in a fan shape is provided in the fixed mold 1, and this space 8 has an undercut portion 9.

Next, the operation will be explained.

First, by clamping the mold, the state shown in FIG. 1 is achieved. In this state, molten metal is introduced into the product cavity 4 via a gate portion (not shown) or the like. This molten metal flows into the space 8 through the gap 7, and a vertical burr with an undercut is forcibly formed.

/8 After the hot water solidifies, open the mold. To open the mold, the movable mold 2 and the slide mold 3 are integrally moved upward with respect to the fixed mold 1 as shown in FIG. 2, and then the slide mold 3 is moved to the right in FIG. When the mold is opened, the casting material 10 is released from the fixed mold 1 while being sandwiched between the movable mold 2 and the slide mold 3. However, since the vertical burr 11 formed integrally with the casting rough material 10 has the undercut portion 9,
Attempts to remain on the fixed type 1 side. For this reason, the vertical burr 11 is sheared from the cast raw material 10 at a portion corresponding to the gap 7 in FIG. Therefore, there are vertical burrs 1 on the released casting rough material 10.
1, and there is no need to provide a vertical deburring process, so it is possible to significantly reduce the number of man-hours and costs.

(Second Embodiment) FIG. 3 is a sectional view of essential parts showing a mold structure according to a second embodiment of the present invention.

The second embodiment differs from the first embodiment in the shape of the space having the undercut portion, but is substantially the same as the first embodiment in other respects.

That is, in the second embodiment, the space 8 having the undercut part has an elongated triangular cross section as shown in FIG. It is formed.

In the second embodiment as well, the space 8 having the undercut portion 9 functions in the same manner as in the first embodiment, and produces the same effects as in the first embodiment.

[Brief explanation of drawings]

Fig. 1 is a sectional view of main parts showing the mold structure according to the first embodiment of the present invention, and Fig. 2 is the state when the mold is opened after casting using the mold according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view of a main part showing a mold structure according to a second embodiment of the present invention. 1-----Fixed type 2--Movable type 3--Slide type (movable type) 4--Product cavity 5--11--Vertical mating surface 6 of fixed type --- Vertical mating surface 7 of the movable mold --- One gap 8 --- One space L --- Undercasing part lO... --m- Casting rough material 11 --- Vertical burr (cast burr) Applicant Toyota Automobile Motor Corporation Figure 1 Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] (1) A mold structure consisting of a fixed mold and a movable mold defining a product cavity, and having a vertical mating surface on the mold mating surface of the fixed mold and the movable mold, wherein the vertical mating surface of the fixed mold and the movable mold is In addition to providing a gap of 0.3 to 0.5 degrees on the mating surfaces of
A mold structure characterized in that a space having an undercut portion communicating with the gap is provided in either a fixed mold or a movable mold forming a vertical mating surface.