JPH0634040Y2 - Mold structure of low pressure casting machine - Google Patents

Description

[Detailed Description of the Invention] [Industrial application] The present invention relates to a mold structure of a low-pressure casting machine, and more specifically, a product cavity of a mold placed on a die base, and a molten metal holding furnace provided below the die base. The present invention relates to a die structure of a low-pressure casting machine that allows the molten metal inside to communicate with each other through a stalk and a die.

[Conventional technology]

In the low-pressure casting method, the surface of the molten metal in the molten metal holding furnace is pressurized with compressed air or an inert gas to a pressure of 1 atm or less relative to the atmospheric pressure to push the molten metal up, and the molten metal is put into the mold placed above from below. Is a method of feeding and casting, and is mainly used for casting light alloy castings.

The apparatus used for this low pressure casting conventionally has a structure as shown in FIG. The mold 100 is generally composed of an upper mold 100a and a lower mold 100b, the lower mold 100b is placed on a die base 102, and the upper mold 100a is connected to a rod 104a of a cylinder 104 and can be raised and lowered. The product (casting) extrusion device 106 is attached to the upper mold 100a side, and the product shape is determined so that the product adheres to the upper mold 100a when the mold is opened. Therefore, after the molten metal is solidified, in order to take out the product from the mold 100, the upper mold 100a is raised and the mold is opened, and then the extruder is used.
This is done by driving the 106 to push out the product from the upper mold 100a. In addition, below the die base 102, the container 1
Molten metal 110 is stored in 08, Stoke 112, base 114
The molten metal is filled into the product cavity via the.

On the other hand, when the product adheres to the lower mold due to the shape of the product, it is necessary to push the product out of the lower mold.

As a product with a product extrusion device on the lower die side,
60-137186). In this apparatus, as shown in FIG. 3, a container 20 containing a die base 202 and a molten metal 210 is provided.
An extruding plate 216 is arranged between the sheet and the sheet 8. In addition, the extrusion plate 216
An extruding pin 218 extending to the product cavity is provided, and an extruding rod 220 for driving the extruding plate 216 is provided outside the container 208. The last two digits of other symbols are
It is the same as the same member in FIG.

[Problems to be solved by the invention]

By the way, in the case where the extrusion device 206 is provided on the lower die side, there are the following problems.

Since the extrusion plate 216 is disposed between the die base 202 and the container 208 that houses the molten metal 210, the height of the entire casting apparatus is increased, and a larger space is required. In addition, the extrusion plate 21
6. Since the push rod 220 and the like are near the container 208, they are likely to be deformed by receiving heat. Further, since the positions of the push-out pin 218 and the push-out rod 220 are largely deviated from each other, they are cantilevered and cannot be sufficiently pushed out.

Therefore, the present invention provides a die structure for a low-pressure casting machine that is space-friendly, is less susceptible to the heat generated from the molten metal, and has an extrusion device provided on the lower die side that can reliably extrude products. The purpose is to provide.

[Means for solving problems]

Therefore, the present invention is characterized in that an extrusion plate and an extrusion cylinder are provided above the die base.

Specifically, the structure of the present invention is as follows.

The present invention includes a mold (10) mounted on a die base (14).
Low pressure casting machine for communicating the product cavity (12) of the above and the molten metal (30) in the molten metal holding furnace (20) provided below the die base (14) through the tubular molten metal flow passages (24, 28). It is a mold structure in.

This mold (10) consists of an upper mold (10a) and a lower mold (10b),
Inside the lower mold (10b) or lower mold (10b) and die base (14)
A space (34) for arranging the extruding plate (36) is provided between and. The extrusion plate (36) arranged in the space (34) penetrates the lower mold (10b) and the product cavity (12).
An extruding pin (38) whose tip extends is erected on the inner surface of the die, and a die base (14) is provided with a cylinder (42) for vertically moving the extruding plate (36).

[Action]

According to the mold structure of the low-pressure casting machine of the present invention, after the molten metal (30) supplied into the product cavity (12) is solidified, the extruded plate (36) is moved by the cylinder (42) attached to the die base (14). If you push up, the extrusion pin (38) protrudes into the product cavity (12) and the solidified casting is
b) Push away from you. Since the extrusion plate (36) and the cylinder (42) are provided on the upper side of the die base (14), heat in the molten metal holding furnace (20) is not directly transferred to the extrusion plate (36) and the like. Further, since the extruded plate (36) is arranged in the lower mold (10b) or in the space (34) between the lower mold (10b) and the die base (14), the height of the casting apparatus is increased. There is no. Further, if both ends of the extruding plate (36) are supported by the cylinders (42), the rigidity of the extruding plate (36) is increased and the pushing force by the extruding pin (38) is increased.

〔Example〕

Next, an embodiment of the mold structure of the low pressure casting apparatus according to the present invention will be described with reference to FIG.

FIG. 1 is a schematic configuration diagram of a low pressure casting machine to which die casting is applied.

In FIG. 1, 10 is a mold as a mold, and the upper mold 10
It is composed of a and a lower mold 10b, and the product cavity 12 is defined by the upper mold 10a and the lower mold 10b. The lower die 10b is attached on the die base 14, and the upper die 10a is attached to the tip of a rod 18a of a cylinder 18 provided on a frame 16 standing on the die base 14. Therefore, the upper die 10a is
It can be raised and lowered by the operation of 8.

Further, below the die base 14, a container (crucible) for holding the molten metal, that is, a molten metal holding furnace 20 is provided. A furnace lid 22 is placed on the upper portion of the molten metal holding furnace 20, and a hole 26 through which the stalk 24 is inserted is provided at substantially the center of the furnace lid 22. Then, the flange portion 24a provided at one end of the stalk 24 is locked to the shoulder portion of the hole 26 provided in the furnace lid 22, and the other end of the stalk 24 extends toward the bottom portion of the molten metal holding furnace 20. ing. A substantially cylindrical base 28 is provided on the upper portion of the stalk 24, and the upper end of the base 28 has a lower die 10b.
Is connected with the opening. Incidentally, 30 is a molten metal in the molten metal holding furnace 20.

That is, the product cavity 12 and the molten metal 30 are communicated with each other by a tubular molten metal flow path.

Next, the lower die extrusion device 32 will be described.

In the lower die extrusion device 32, the space 3 penetrated by the lower die 10b
4 is formed, and the pushing plate 36 is inserted into the space 34. A plurality of extruding pins 38 are embedded in the extruding plate 36, and the extruding pins 38 extend through the lower die 10b to the product cavity surface of the lower die 10b. Both ends of the push-out plate 36 are fixed to the connecting plate 40 by bolts. The connecting plate 40 has an inverted U-shape, and a recess 40a is formed at the bottom of the U-shape. The rod 42a of the extrusion cylinder 42 arranged in the die base 14 is fitted into the recess 40a.

Next, the upper die extrusion device 44 will be described.

In the upper die extrusion device 44, an extrusion cylinder 48 is arranged on a top plate 46 supported by the frame 16. Rod 48a of extrusion cylinder 48
Is connected to the extruding plate 50, and the extruding plate 50 is the upper die 10a.
It is arranged in the space 52 formed in. A plurality of extruding pins 54 are planted on the lower side of the extruding plate 50, and the extruding pins 54 extend through the upper die 10a to the product cavity surface of the upper die 10a.

Next, the operation will be described.

First, the cylinder 18 is driven to lower the upper mold 10a toward the lower mold 10b to perform mold clamping. Then, by a pressurized gas supply means (not shown), the molten metal holding furnace 20 is heated to the atmospheric pressure at 0.1 to 0.5.
A pressurized gas with added atmospheric pressure is supplied. With this pressurized gas, the molten metal 30 in the molten metal holding furnace 20 is introduced and filled into the product cavity 12 of the mold 10 through the stalk 24 and the die 28. After the molten metal in the product cavity 12 is solidified after a certain period of time, by stopping the pressurization, the unsolidified molten metal 30 below the die 28 falls into the molten metal holding furnace 20 by weight.

After that, the pushing cylinder 42 on the lower die 10b side is operated so as to generate a pushing force larger than the die clamping force. For example, if the pressing force of the upper mold 10a by the cylinder 18 is about 10t, the pushing cylinder 42 is operated so that the pushing force is about 20t. Therefore, the push-up force of the push pin 38 via the push plate 36 is
Since it is larger than the mold clamping force, the upper mold 10a is pushed up through the solidified casting (for example, Al casting). That is, the upper mold 10a is separated from the lower mold 10b and the mold 10 is opened,
The casting separates from the product cavity surface of the lower mold 10b. In this case, the pressurized fluid in the cylinder 18, such as pressurized air, escapes through a relief valve (not shown). Then, when the pushing cylinder 42 makes the maximum stroke (when it makes a stroke of about 10 mm), the cylinder 18 continues to move and the upper die is moved.
Pull 10a upward. That is, the mold is opened by the cylinder 18. In this case, since the casting is attached to the product cavity surface of the upper die 10a, the casting is further separated from the product cavity surface of the lower die 10b. After that, the extrusion cylinder 48 on the side of the upper die 10a operates and the extrusion pin 54 protrudes downward from the product cavity surface of the upper die 10a, and as a result, the casting is cast on the upper die 10a.
And the casting is discharged. Thus, one cycle of low pressure casting is completed.

In the mold structure described above, the extrusion plate 36 is attached to the die base 14
Since it is provided on the upper side of, the extrusion plate 36, the extrusion pin 38, etc. are less likely to be affected by the heat of the molten metal 30 in the molten metal holding furnace 20,
It is possible to prevent thermal deformation of the 38 or the like and a defect in the extrusion function due to the thermal deformation. Also, the lower cylinder 10b side extrusion cylinder 42 and extrusion plate 3
Since 6 etc. are on the die base 14, maintenance and inspection of these are easy.

Although the specific embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, but includes various embodiments within the scope of the claims for utility model registration.

[Effect of device]

As described above, according to the mold structure of the low-pressure casting machine of the present invention, the heat from the container containing the molten metal is not directly transmitted to the extruded plate, and is not affected by the heat. Further, the casting apparatus does not become expensive, which is advantageous in terms of space. In addition, the rigidity of the extruded plate is high, and it is possible to reliably extrude the product.

Further, since the extrusion cylinder is located on the die base, there is an advantage that maintenance is easy.

[Brief description of drawings]

FIG. 1 is a drawing for explaining an embodiment of a die structure of a low pressure casting machine according to the present invention, and is a schematic configuration diagram of the low pressure casting machine. 2 and 3 are drawings for explaining a conventional example. FIG. 2 is a schematic configuration diagram showing a low pressure casting machine provided with an extrusion device on the upper die side. FIG. 3 is a schematic configuration diagram showing a low-pressure casting machine provided with an extrusion device on the lower die side. 10 …… Mold 10a …… Upper mold 10b …… Lower mold 12 …… Product cavity 14 …… Die base 20 …… Melting furnace (container) 24 …… Stoke 28 …… Mouth 32 …… Extrusion mechanism 34 …… Space 36 ...... Extrusion plate 40 ...... Connection plate 42 ...... Extrusion cylinder

Claims (1)

[Scope of utility model registration request] 1. A mold of a low-pressure casting machine in which a product cavity of a mold placed on a die base and a molten metal in a molten metal holding furnace provided below the die base are connected through a molten metal flow path. In the structure, the mold is composed of an upper mold and a lower mold, and the extrusion plate moves up and down in the space below the product cavity in the lower mold or in the space formed between the lower mold and the die base. The die base is disposed so that the extrusion plate has an extruding pin that extends through the lower die and has a tip extending to the product cavity surface of the lower die, and that moves the extruding plate up and down. The mold structure of the low-pressure casting machine is characterized in that it is mounted on the upper surface side of the.