JPH064999Y2 - Reticulated filter structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mesh filter structure for filtering molten metal.

(Prior art) A mesh filter woven of fire-resistant fibers such as glass fiber and carbon fiber is effective in separating foreign matter such as slag and non-ferrous metals such as non-ferrous metal such as aluminium, cast iron and cast steel. Due to its superiority, it has attracted attention in the field of the casting industry in recent years.

This type of reticulated filter is a flexible reticulated woven fabric woven with fire-resistant fibers, which is solidified with phenolic resin, etc., and given shape retention, and then the molten metal flow path of a sand mold gate or runner for casting. It is generally arranged and used on the way.

As shown in FIG. 4, the reticulated filter is usually arranged on the mold dividing surface 24 at the bottom of the sprue channel 23 formed by shifting from the upper mold 21 of the sand mold to the lower mold 22, Both sand type 2
Used by being sandwiched between 1,22. In the figure, 25 is a mesh filter, 26 is a spout bottom, 27 is a runner passage, 28 is a riser casting space, 29 is a product casting space, and 30 is a filter installation for mounting the mesh filter 25 on the upper surface. It is a core.

(Problems to be solved by the invention) However, in this case, it is difficult to install the center of the reticulated filter in alignment with the center of the molten metal flow path, and the reticulated filter of the reticulated filter is moved when the mold is moved or when the casting cavity is cleaned by air blow. In some cases, the position of the mesh filter does not exist on the cross section of the molten metal flow path due to the displacement of the position, and the function as a filter may not be sufficiently fulfilled.

In order to solve the above-mentioned conventional drawbacks, the applicant has proposed in Japanese Utility Model Application No. 6264725/1987 that a mesh filter is partially bonded to a filter mounting plate having melt flow holes with an inorganic adhesive. Although the filter structure is disclosed, in the molten metal filtration, the central plate portion interposed between the molten metal flow holes arranged in the filter mounting plate hinders the molten metal flow through, which hinders smooth and rapid filtration work. There is.

The present invention has been made in view of the above problems, and when installing a mesh filter in a molten metal flow path, a misalignment is unlikely to occur, the installation is easy and the filtration time for molten metal melt can be shortened. The purpose is to provide a structure.

(Means for Solving the Problem) A mesh filter structure of the present invention made to achieve the above object is a mesh filter formed by a refractory fiber, which is formed by surrounding a melt flow through hole in a frame with a fire resistance. The filter mounting frame is partially adhered to the filter mounting frame by an inorganic adhesive, and the peripheral edge portion is projected to the outside of the filter mounting frame.

(Operation) Since the reticulated filter is used by being adhered to the filter mounting frame, when the reticulated filter is installed so as to be aligned with the molten metal flow path of the mold of the reticulated filter, it may be installed together with the filter mounting frame. Since the filter is easy to install and is relatively heavy, the filter is not displaced.

Further, since the reticulated filter is adhered to the filter mounting frame via an inorganic adhesive, a heat resistant reticulated filter structure is obtained, and the reticulated filter is partially adhered to the filter mounting frame. Because
Even if the mesh filter contracts due to the heat of the melt during passage of the melt, the contracting force is relieved without immediately acting on the filter mounting frame, and the contraction of the mesh filter prevents breakage such as fiber cutting. It

Further, since the peripheral portion of the mesh filter projecting to the outside of the filter mounting frame is clamped in a tension state by the upper mold and the lower mold on the dividing surface of the mold, the mesh shape is generated by the impact received during the molten metal filtration. It is possible to prevent the filter from hanging.

Further, since the mesh filter is attached to the filter mounting frame, the molten metal flow through hole formed in the frame acts as one large molten metal flow through hole aligned with the molten metal flow passage,
The molten metal can be passed smoothly and quickly, which shortens the filtration work.

(Embodiment) FIGS. 1 and 2 show a mesh filter structure 1 according to an embodiment of the present invention. In the mesh filter structure 1, a square mesh filter 4 is partially adhered to the upper surface of a circular ring-shaped filter mounting frame 2 by an inorganic adhesive, in the illustrated example, three spots 5 are equally spaced. Become. In this case, one side of the mesh filter 4 has a length substantially equal to the diameter of the filter mounting frame 2, so that the triangular peripheral edges 6 of the four corners of the mesh filter 4 are located outside the filter mounting frame 2. It was configured to protrude. As the inorganic adhesive, an alumina-based adhesive for adhering a ceramic material is suitable. An example of such an adhesive is Cerabon (trade name, manufactured by Denki Kagaku Kogyo Co., Ltd.). The adhesive portion 5 is not limited to the one shown in the figure, and a plurality of adhesive portions 5 may be provided at appropriate places.

The filter mounting frame 2 is made of a fire-resistant material, which is manufactured by sand molding such as a pepset molding molding method or by baking low-powder powder or the like after wet press molding.

As the reticulated filter 4, it is preferable to use one formed of glass fibers (silica long fibers) containing Si ₈ content of 75% by weight or more.

When such high-purity glass fiber is used, it can be applied to all kinds of cast iron melts below 1450 ° C and other metal melts. “Compatible here” means that the glass fiber does not slag even when immersed in the molten metal for 20 seconds. Usually, pouring into the mold is done within 20 seconds.

In the case of the present embodiment, since the mesh filter 4 is bonded at several points on the upper surface of the filter mounting frame 2 as described above, the mesh cloth is used as the mesh filter 4 as it is. Also, when the reticulated filter 4 contracts due to the heat of the molten metal, the contraction is alleviated, and breakage such as cutting of the reticulated filter is prevented. However, a net-like woven fabric that has been previously contracted by a heat treatment after the acid treatment may be used as the net-like filter 4. Alternatively, a mesh woven cloth coated with phenolic resin or the like to provide shape retention may be used as the mesh filter 4.

The area open area ratio of the mesh filter 4 is preferably 12.5 to 32.5%. The reason is that the casting time is less likely to be delayed in this range, and the casting is easily divided at the filter installation portion. In addition, the area open area ratio% is represented by a mesh open area on the filter surface × 100 / total surface area of the filter.

FIG. 3 shows a state in which the above-described mesh filter structure of the present invention is installed in the mold. In the figure, the mold has a sprue channel 13 formed by shifting from the upper die 11 to the lower die 12, and is opened on the mold dividing surface of the lower die 12, and the sprue channel 13 is formed.
A circular annular installation recess 14 is provided along the inner peripheral surface of the. Reference numeral 15 is a runner passage, and a product casting space and the like are formed in the end of the passage as is conventional.

The mesh filter structure of the present invention is installed in the following manner. That is, by fitting and housing the filter mounting frame 2 of the mesh filter structure 1 in the recess 14 provided in the lower mold 12, the mesh filter structure 1 of the present invention is installed without displacement. At the same time, since the melt passage hole 3 having a large diameter substantially the same as that of the sprue passage 13 formed by being surrounded by the filter mounting frame 2 is installed in a state of self-aligning with the sprue passage 13. , The predetermined position is easily obtained, and the structure 1 is positioned by the recess 14,
The positional deviation is prevented, and it is stably held at the predetermined installation position.

In this installed state, the reticulated filter 4 of the reticulated filter structure 1 has four peripheral edge portions 6 at the lower mold 12
Since it is positioned in a superposed state on the upper surface of the division surface of, when the upper mold 11 is superposed on the lower mold 12 to close the mold from this state,
These peripheral portions 6 of the mesh filter 4 are sandwiched by the upper mold 11 and the lower mold 12.

Thus, from this state, when pouring the molten metal from above the spout channel 3, foreign matters such as slag and slag contained in the mesh filter 4 are removed, and the entire lower surface of the filtration surface of the mesh filter 4 is Since the melt passage hole 3 has a large diameter which is substantially the same as the diameter of the sprue passage 13, the filtered melt can be passed through immediately, so that a smooth and quick filtration operation can be performed.

Further, since the mesh filter 4 is sandwiched by the upper mold 11 and the lower mold 12 via the peripheral portion 6, the mesh filter 4 is kept in a tension state even when the molten metal is impacted by falling. , Its sagging can be prevented and a good filtration effect can be maintained.

Further, since the mesh filter 4 is partially bonded to the filter mounting frame 2 with the inorganic adhesive, that is, at the plurality of bonding portions 5, even if the mesh filter 4 is thermally contracted by the molten metal. Since the shrinkage is partially dispersed and relaxed, damage due to heat shrinkage can be prevented. Holds stable and good filtration action.

Further, as is apparent from the above, the mesh filter 1 of the present invention is the core for installing the filter in the mold as in the conventional case.
Compared with the case where 30 is used and the reticulated filter 25 is installed on the upper surface thereof, not only the work of installing the mold in the mold can be performed very easily and surely, but also the positional deviation can be prevented.

(Effect of the Invention) As described above, the mesh filter structure of the present invention is one in which the mesh filter is partially attached to the filter mounting frame via the inorganic adhesive, so that the spout channel of the mold Not only can the work of aligning the molten metal flow holes and installing it horizontally be extremely easy, but also the molten metal can be filtered satisfactorily and quickly. Furthermore, the peripheral portion of the mesh filter can be attached to the filter. Since it is projected outward from the frame, the peripheral portion can be directly clamped by the upper mold and the lower mold, so that the mesh filter can be firmly fixed and held, and it is held in a tension state, so that it is not impacted by the molten metal. Even if it can prevent sagging, stable and good filtration performance can be maintained,
In addition, since the mesh filter is partially adhered to the filter mounting frame, heat shrinkage of the mesh filter due to molten metal can be mitigated, the mesh filter can be prevented from being broken, and the structure is simple as a whole. With such an effect, it is easy to manufacture.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the mesh filter structure of the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. FIG. 4 is a sectional view of a sand mold provided with a conventional mesh filter. 1 ... Reticulated filter structure, 2 ... Filter mounting frame, 3 ... Melt flow hole, 4 ... Reticulated filter, 5 ...
Adhesive part.

Claims (1)

[Scope of utility model registration request] 1. A reticulated filter made of refractory fibers is partially adhered to a refractory filter mounting frame surrounded by a molten metal flow through hole by an inorganic adhesive, and its peripheral portion is mounted on the filter. A mesh filter structure formed by protruding to the outside of the frame.