JPS61150763A - Flash removing method of vacuum valve unit - Google Patents

Abstract

PURPOSE:To automate flash removing and to reduce production costs by dropping flashes formed between a die and a valve plug by up-and-down motion of the valve plug after the valve plug and a seat are moved up using a vacuum pass closing mechanism actuated by movement of the valve plug sliding in a hole communicating with a cavity of the die. CONSTITUTION:The valve plug 15 sliding in the hole communicating with the cavity 12 of the die 11 brings the cavity 12 to a vacuum by communicating the cavity 12 with a vacuum source 17 by down movement of the valve plug 15 apart from the seat 14 of the valve plug 15 using a cylinder 19. The valve plug 15 is abutted on the seat 14 and is lifted to close the vacuum pass and vacuum casting is performed. The valve plug 15 is separated from a casting by lifting both the seat 14 and valve plug 15 using a cylinder 21 after the casting solidifies sufficiently. Next, the flashes between the die 11 and the valve plug 15 are dropped by several up-and-down motions of the valve plug 15 using a cylinder 18. The method automates flash removal taking long time and labor so far to increase working efficiency and to reduce production costs.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to a vacuum valve provided in a vacuum die casting machine that connects a cavity to a vacuum source to prevent molten metal from flowing into the vacuum source from the cavity during injection. This article relates to a method for removing burrs generated from the unit.

[Prior art]

Conventional vacuum valve units are usually installed on one side of both molds on the parting line between a fixed mold and a movable mold, and the valve body of the vacuum valve unit is installed on both molds. It slid inside the gas vent leading to the cavity to open and close the vacuum source. When a product is cast in such a vacuum die-casting machine, burrs are generated in the gap between the gas vent hole and the valve body. When taking out the product after opening the mold, if the vacuum valve unit is installed on a fixed mold, it will occur in the gap between the same mold and the valve body, and if it is installed in a moving mold, it will occur in the gap between the same mold and the valve body. It is difficult to remove burrs because the gap is small. That is, this burr cannot be easily removed by air blowing or the like, and automation is difficult because it is done by one person, which increases the cost of the product.

[Purpose of the invention]

The present invention eliminates these drawbacks, and its purpose is to:
To provide a method for removing burrs from a vacuum valve unit that reduces the cost of the product by automatically removing burrs generated in the gap between the mold and the valve body without adding a burr removal mechanism. be.

[Key points of the invention]

The method for removing burrs from a vacuum valve unit in the present invention is as follows:
In a vacuum valve unit in which a valve body slides through a hole in a mold facing a passage communicating with a cavity and is moved by a cylinder to communicate or close the cavity to a vacuum source, the gap between the valve body and the hole in the mold By moving the valve body up and down several times using a cylinder, the burrs can be removed.
The feature is that it is made to fall by applying an extrusion action.

[Embodiments of the invention]

The present invention will be explained below with reference to figures showing examples.

The figure is a view cut along a dividing plane between a fixed mold and a movable mold, and a cavity 12 is formed in the mold 11 (which may be either the fixed mold 2 or the movable mold), and the cavity 12 has a passage 13. is connected to. A sheet 14 having a central hole 14A is inserted partially into the mold 11 and provided with the open end of the hole 14A in contact with the upper extension of the passageway 13.
A is communicated with a vacuum source 17 by a hole 16.

A valve body 15, which is guided by a seat 14 and fixed to the tip of a piston 19 of an A cylinder 18 whose lower end is attached to the seat 14, is slidably inserted into a hole in the mold 11 directed from above to below the passage 13. It has been inserted.

In the illustration, the upper slope of the valve body 15 is the hole 14A of the seat 14.
Since it is in contact with the end face, communication between the passage 13 and therefore the cavity 12 and the vacuum source 17 is closed, but the A cylinder 1
8, and lower the upper surface of the valve body 15 to below the upper side of the passageway 3, the cavity 12
is connected to a vacuum source 17 via a passage 13.

In FIG. 2, a bracket 2° is fixed to the upper side of the mold 11, and the lower end of a piston 22 of a B cylinder 21 attached to the upper surface of the bracket 20 is fixed to an A cylinder 18. In this B cylinder 21, the lower surface of the valve body 15 is flat and in contact with the molded product (not shown), so the valve body 15 gets in the way when opening the mold and extruding the molded product. By pushing up pressure fluid into the rod side of the B cylinder 21, the seat 14 and the valve body 15 are raised via the A cylinder 18 and separated from the molded product.

Note that if the lower surface of the valve body 15 is made sloped and the slope is in the direction in which the molded product comes out when the mold is opened and the molded product is extruded, the bracket 2
0. B cylinder 21 and piston 22 are unnecessary.

In this case, a rotation prevention mechanism such as a key (not shown) is required for the piston 19 so that the valve body 15 always faces in the same direction.

Next, the operation of the embodiment described above will be explained.

When pressure fluid flows into the head side of the A cylinder 18 and the piston 19 is lowered from the illustrated state, the upper surface of the valve body 15 is lowered to below the upper side of the passage 13.

The cavity 12 connects the vacuum source 1 from the passage 13 through the hole 16.
7, the cavity 12 is in a vacuum state.

When the cavity 12 reaches a specified vacuum pressure, by supplying all the pressure fluid to the rod side of the A cylinder 18, the valve body 15 rises and returns to the position shown, closing the hole 14A. After filling the cavity 12 with molten metal from an injection mechanism (not shown), the process waits for the molten metal to cool and solidify. When the molten metal solidifies into a molded product, pressure fluid is flowed into the rod side of the B cylinder 21 to raise the valve body 15 and seat 14 through the A cylinder 18 and separate the valve body 15 and the like from the molded product. .

If the valve body 15 and the like are released from the molded product in this way, the mold can be opened and the molded product can be extruded.

Burrs (not shown) are generated in the gap between the mold 11 and the tip of the valve body 15. When extruding the product, the sheet 14, the valve body 15, and the iB cylinder 21 are used to raise the product, and at this time, the burr either rises together with the valve body 15, or adheres to the mold 11 and remains together with the mold 11, or is further or intermediate therebetween. In some cases.

Here, in the present invention, the seat 14 and the valve body 15 are placed in the raised position, and the valve body 15f! L: Move up and down several times using the A cylinder 18. Due to this operation, in any of the above cases, the burr easily falls due to the shock and the pushing action of the valve body 15.

〔Effect of the invention〕

As explained above, in the method of removing burrs from a vacuum pulp unit according to the present invention, the notebook and the valve body are raised to a raised level before product extrusion. /C The burrs generated in the gap between the tip of the valve body and the mold were caused to fall by moving the valve body up and down several times to apply a shock and extrusion action. For this reason, burr removal, which was difficult in the past, can be done automatically, reducing the cost of the product.Furthermore, since the vertical movement of the valve body is a necessary configuration for vacuum pulp units, burr removal does not increase costs. It has advantages such as:

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the present invention. 11... Mold, 12... Cavity, 13... Passage, 15... Valve body.

Claims (1)

[Claims] In a vacuum valve unit in which a valve body sliding in a hole in a mold facing a passage communicating with a cavity is moved by a cylinder to communicate or close the cavity to a vacuum source, the valve body and the hole in the mold A method for removing burrs from a vacuum valve unit, wherein the burrs generated in the gap are caused to fall by applying a shock and extrusion action to the burrs by moving the valve body up and down several times using the cylinder.