JPH031101B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for cleaning an injection sleeve, and more particularly to a method for cleaning an injection sleeve of a vertical casting type injection molding apparatus.

[Prior art] A vertical casting type injection molding device has an injection sleeve that
It is configured to be able to swing between a vertical position where it docks with the runner on the mold side and fills the cavity with molten metal, and an inclined position where it receives molten metal from the ladle.

FIG. 3 shows the main parts of a conventional vertical casting type injection molding apparatus of this type.

In FIG. 3, 1 is a fixed mold, 2 is a movable mold, and is shown as a vertical clamping injection molding apparatus, and tie bars, mold clamping devices, etc. are omitted.

A mold cavity 3 is formed on the abutting surface between the fixed mold 1 and the movable mold 2, and the fixed mold 1
A runner 4 is formed on the side. On the other hand, 5 is an injection sleeve, into which a plunger tip 7 fixed to the tip of an injection plunger 6 is slidably fitted.

The injection sleeve 5 and the injection plunger 6 can swing and move up and down together, and the injection plunger 6 is also configured to be able to move up and down inside the injection sleeve 5 separately.

When the injection sleeve 5 receives the molten metal 9, it is tilted so as to face the ladle 8, as shown in FIG. 3, and the plunger tip 7 is also retracted. In this state, a predetermined amount of molten metal 9 in the ladle 8 is supplied into the molten metal sleeve 5, and when the supply is finished, the injection sleeve 5 is rotated counterclockwise in FIG. 4 and the axis of the injection sleeve 5 coincide with each other.

In this state, the injection sleeve 5 rises at the same time as the plunger tip 7 and docks with the lower end of the melt channel 4. After that, the injection plunger 6 injects the molten metal 9 into the mold cavity 3 which is in the clamped state. is ejected.

By the way, what is important in the above-mentioned injection molding equipment is that in order to obtain high-quality molded products,
The point is to suppress the temperature drop of the molten metal as much as possible before filling it into the cavity.

Therefore, the molten metal 9 is transferred from the ladle 8 to the injection sleeve 5.
When it is discharged into the interior, it is best to immediately dock it with the runner 4 and perform injection, but from the ladle 8, the remaining molten metal such as the molten metal 9 and the molten metal that has adhered to the outer circumferential surface of the ladle are drip-shaped. It is dripping.

If the injection sleeve 5 is rocked in this state, molten metal will adhere to the upper end surface of the injection sleeve 5.
If the molten metal is docked to the runner side as it is, a gap will be created between the molten metal and the stationary mold 1, and the molten metal will enter this gap and cause flash.

Therefore, in the past, a timer was provided for draining the hot water, and the injection sleeve was operated after 1 to 3 seconds had passed until the molten metal had sufficiently dripped.

Furthermore, when pouring, even if there are no drops of molten metal on the top surface of the injection sleeve 5, if the injection sleeve 5 is swung relatively quickly to bring it into a vertical position, some of the molten metal will fly out and the injection It accumulates on the top surface of the sleeve 5,
Causes problems.

[Problems to be Solved by the Invention] However, as described above, when the operation of the injection sleeve 5 is stopped for 1 to 3 seconds, the amount of heat radiated by the molten metal during this time is extremely large, causing damage to the injection molded product. The impact on quality was extremely large.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention includes blowing gas to the connection surface of the injection sleeve to the mold side during the docking operation of the injection sleeve to the mold side. A method was adopted to clean the injection sleeve by blowing off the solid matter made of molten metal drops adhering to the top surface of the injection sleeve.

More specifically, molten metal is supplied from the upper opening into the injection sleeve of the vertical casting mold at a hot water supply position that is spaced downward and laterally away from the lower surface of the mold, and the injection sleeve is connected to the injection sleeve connection section at the lower part of the mold. When the plunger tip inside the injection sleeve is advanced and the molten metal is poured into the mold cavity, the plunger tip is moved horizontally in the direction and then moved upward to connect to the injection sleeve connecting portion at the bottom of the mold. While the injection sleeve is being moved laterally in the direction of the injection sleeve connection section, gas is blown onto the connection surface (the top surface of the injection sleeve) from a nozzle installed at a position opposite to the hot water supply on the bottom surface of the mold, thereby connecting the injection sleeve. The connecting surface of the injection sleeve is cleaned by blowing away the molten metal and other deposits adhering to the surface to the outside of the hot water supply position.

[Operation] When the method described above is adopted, the injection sleeve receives the molten metal from the ladle and reaches the docking position on the mold side. molten metal can be removed.

[Example] Hereinafter, the present invention will be described in further detail based on an example shown in the drawings.

FIGS. 1 and 2 illustrate one embodiment of an injection molding apparatus to which the method of the present invention is applied, and is illustrated as an injection molding apparatus of horizontal mold clamping and vertical casting molds.

In the figure, 10 is a fixed plate, and this fixed plate 10
A fixed mold 13 is fixed to the holder via keys 11 and 12. Between this stationary platen 10 and an end platen (not shown), four tie bars 14 are suspended horizontally in a rectangular arrangement.
A movable platen 15 is slidably fitted to the movable platen 4, and a movable mold 16 is fixed to the movable platen 15.

A cavity 17 is formed on the abutting surfaces of the movable mold 16 and the fixed mold 13.

In addition, a cavity 1 is provided on the butt surface 18 of the mold.
A runner 19 communicating with the runner 7 is formed, and a fixed sleeve 2 cut in half is formed at the lower end of the runner 19.
0 and 21 are fixed, and the two are butted against each other when the mold is clamped to form a cylindrical fixed sleeve.

The movable mold 16 is fixed to the movable platen 15 via a key 22, and a product extrusion device 23 is inserted into the space inside the movable mold 16 formed between the movable platen 15 and the movable platen 15.
is provided.

Note that the fixed platen 10 is fixed on the machine base 24, and the movable platen 15 is placed on the machine base 24 so as to be freely slidable.

Movement of the movable platen 15 and application of mold clamping force are provided by a mold clamping cylinder rod 25 and a toggle link mechanism 26 (not shown).

On the other hand, a pit 27 is formed below the machine base 24 on the floor side, and a vertical casting unit 28 is provided within this pit 27.

The details of this vertical casting unit 28 will be explained below.

The vertical casting unit 28 has a frame 30 connected and fixed to the machine base side via a rod 29, and a vertical injection device 31 is rotatably supported on the frame 30 in the middle thereof.

The injection device 31 has an elongated frame 32, an injection cylinder 33 is fixed to the lower end of the frame 32, and a plunger 34 is connected to the tip of the piston rod of the injection cylinder 33. A plunger tip 34a is attached to the tip of the plunger 34.

Further, an injection sleeve 35 is attached to the upper end of the frame 32 and is moved up and down via a hydraulic device (not shown).

Further, on the left side of the frame 30 in FIG. 2, a middle portion of a cylinder 37 for tilting is rotatably attached via a bracket 36 via a shaft 38.

The tip of the piston rod of the cylinder 37 is rotatably connected to the lower part of the frame of the injection device 31 via a bracket 39.

On the other hand, a frame 30 of an injection device (not shown)
One end of an arm 40 is fixed to one end of a support shaft for the arm 40, and at a position where it contacts the free end side of the arm 40, a millimeter switch 41a for detecting the tilting limit and a limit switch for detecting the vertical state are installed on the side surface of the frame 30. 41b is fixed. In the illustrated state, the limit switch 41b is in contact with the arm 40 and is turned on.

On the other hand, 42 is a ladle of the type that discharges and supplies the molten metal 44 from the bottom, 42a is a valve stem that can be raised and lowered, and when the injection device 31 is rotated to its tilting limit as shown by the chain line in FIG. 44 into the injection sleeve 35.

Further, a nozzle 43 is provided on the side opposite to the hot water supply position with respect to the injection sleeve 35 on the lower surface of the mold using a fixed part such as the machine base 24 so that the nozzle 43 reaches the vicinity of the injection sleeve 35 when it becomes vertical. ing.

This nozzle 43 jets out an inert gas such as air or nitrogen gas, and is arranged so that the jetting direction is tangent to the rotational trajectory of the upper surface of the injection sleeve 35.

Next, the operation of this embodiment configured as above will be explained.

The timing before and after the fixed mold 13 and the movable mold 16 are matched is determined by the cylinder 3 for tilting.
7 is activated, its piston rod is retracted,
The injection device 31 is tilted away from the lower side of the mold as shown by the chain line in FIG. to face.

At this time, as shown in Figure 1, the plunger 3
The plunger tip 34a at the tip of the plunger 4 is lowered, and in this state, by opening the valve stem 42a in the ladle 42, a predetermined amount of molten metal 44 is supplied from the ladle 42 into the injection sleeve 35.

When the supply of the molten metal 44 is finished, the cylinder 37 is activated, its piston rod is extended, and the injection device 31 is rotated so as to be in a vertical position as a whole.

At this time, since gas is ejected from the nozzle 43, even if there is molten metal adhering to the vicinity of the opening at the upper end of the injection sleeve 35, the adhering material is blown away by the ejected gas and cleaning is performed. .

In addition, in this way, the vertical casting type injection sleeve 35
When molten metal is supplied from the ladle 42 into the injection sleeve 35 at a position spaced downward and laterally away from the bottom surface of the mold, it is necessary to Since the ladle 42 is moved onto the injection sleeve 35 from the side opposite to the mold to supply hot water, if a part of the molten metal drips from the ladle 42 and falls onto the connecting surface, which is the upper surface of the injection sleeve 35, the molten metal will be removed. falls on only about half of the upper surface of the injection sleeve 35 on the side opposite to the mold. Therefore, deposits such as molten metal and solidified molten metal will adhere only to the side opposite to the mold from the center of the upper surface of the injection sleeve 35.

By the way, in the present invention, this injection sleeve 35
During the operation in which the upper surface is moved laterally toward the mold side, gas is blown onto the upper surface of the injection sleeve 35 from a nozzle provided on the mold side, that is, at a position opposite to the hot water supply on the lower surface of the mold. The deposits on the side opposite to the mold from the center of the upper surface of the sleeve 35 do not fall into the injection sleeve 35 at all, but are sufficiently and reliably blown away into the outside air on the side opposite to the mold and removed.

Further, in the present invention, as described above, during the operation in which the upper surface of the injection sleeve 35 is moved laterally from the hot water supply position to the mold side, gas is blown onto the upper surface of the injection sleeve 35 from the mold side. Therefore, the work of moving the injection sleeve 35 laterally and the work of blowing the gas can be performed at the same time, resulting in extremely high work efficiency. Moreover, the upper surface of the injection sleeve 35 is
Since the gas is moved from a position relatively far away from the nozzle 43 that is spraying the gas, it is gradually moved closer to the nozzle 43, so at first, the deposits are lifted up with a relatively weak gas, and finally, the deposits are lifted up with a relatively weak gas. This creates a state in which the deposits are blown away at once with a strong gas, making it possible to remove the deposits more reliably and easily.

Immediately after this cleaning work is completed, the plunger 34
At the same time, the injection sleeve 35 is raised, the mold-matched fixed sleeves 20 and 21 are docked with the injection sleeve 35, the plunger 34 and the plunger tip 34a are raised, and the molten metal 44 is injected into the cavity 17.

When the injection is completed, the injection sleeve 35 and plunger 34 are lowered, the mold is opened, and the product is taken out.

During this time, the entire injection device 31 is tilted to prepare for the next operation.

[Effect] As is clear from the above description, according to the present invention, a method is adopted in which gas is blown onto the connection surface between the injection sleeve and the mold side during the connection operation of the injection sleeve, so that the injection The molten metal adhering to the top surface of the sleeve can be removed, and immediately after the molten metal is supplied to the injection sleeve, the connecting operation can be started immediately without worrying about the molten metal dripping from the ladle. There is very little decrease in the temperature, and the molten metal does not blow out from the joint surface between the fixed sleeve part and the injection sleeve during injection, and no casting burrs occur, making it safe and producing a good molded product. Can be done.

In addition, when using a vertical casting type injection device of the type adopted in the present invention, when supplying hot water from the ladle to the injection sleeve, as described above, from the center of the upper surface of the injection sleeve, Adhesives such as molten metal and solidified molten metal will adhere only to the sides,
In the present invention, in particular, during the operation in which the upper surface of the injection sleeve is moved laterally toward the mold side, gas is blown onto the upper surface of the injection sleeve from a nozzle provided on the mold side, that is, on the side opposite to the hot water supply position on the lower surface of the mold. Therefore, any deposits on the side opposite to the mold from the center of the upper surface of the injection sleeve will not fall into the injection sleeve at all, but will be sufficiently and reliably blown away into the outside air on the side opposite to the mold and removed. It will be destroyed.

Further, in the present invention, as described above, gas is blown onto the upper surface of the injection sleeve from the mold side during the operation in which the upper surface of the injection sleeve is moved laterally from the hot water supply position to the mold side. The work of moving the injection sleeve laterally and the work of blowing gas can be done at the same time, resulting in extremely high work efficiency. Moreover, since the upper surface of the injection sleeve is moved from a position relatively far away from the nozzle that is spraying gas, gradually closer to the nozzle,
A relatively weak gas is used to float the deposits, and then a relatively strong gas is used to blow off the deposits all at once, making it possible to more reliably and easily remove the deposits.

Furthermore, in the present invention, the nozzle is installed on the side opposite to the hot water supply position on the bottom surface of the mold, without directly attaching the nozzle to the injection sleeve, which becomes extremely hot. Can be kept for a long time.

[Brief explanation of the drawing]

1 and 2 show one embodiment of the present invention. FIG. 1 is a vertical sectional view of the main part, FIG. 2 is a side view (first part vertical sectional view) of the injection molding apparatus, and FIG. The figure is a longitudinal cross-sectional view of the main parts of a conventional structure. 13... Fixed mold, 16... Movable mold, 17... Cavity, 34... Plunger, 34a... Plunger tip, 35... Injection sleeve, 42... Ladle, 4
3... Nozzle, 44... Molten metal.

Claims (1)

[Claims] 1. Supply molten metal from the upper opening into the injection sleeve of the vertical casting mold at a hot water supply position that is spaced downward and laterally away from the lower surface of the mold, and move this injection sleeve laterally toward the injection sleeve connection section at the lower part of the mold. After that, move it upward and connect it to the injection sleeve connection part at the bottom of the mold.
When the plunger tip in the injection sleeve is advanced to cast molten metal into the mold cavity, the upper surface of the injection sleeve is moved laterally from the metal supply position toward the injection sleeve connection part. By spraying gas from a nozzle installed on the connection surface at the position opposite to the hot water supply position on the bottom surface of the mold, the molten metal and other deposits adhering to the connection surface of the injection sleeve are blown away to the outside of the hot water supply position, thereby connecting the injection sleeves. A method for cleaning an injection sleeve, characterized in that the surface is cleaned.