JP2005081397A - Degassing implement for casting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a degassing implement for casting capable of improving cooling effect thereby shortening solidified time, enhancing degassing effect and improving a production yield even in the case of needing a deep core working at the time for producing a casting. <P>SOLUTION: The degassing implement 100 for casting, which is formed in the inner part of a hollow-columnar iron core 100 used for the hole work as cast and is provided with a degassing passage X for exhausting generated gas in a mold from the bottom surface part side of the iron core 100, is provided with a cooling passage Y for reciprocative flowing of cooling gas formed in the inner part of the iron core 100. In the degassing implement 100, the degassing passage X is constituted so as to communicate with the cooling passage Y, and the degassing is performed with a venturi effect by utilizing the reciprocative flowing of the cooling gas in the cooling passage Y. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a casting gas venting tool capable of venting (discharging) a gas generated in a mold (gas generated in the mold) during a casting process requiring a punching process.

  For example, when casting aluminum alloy parts (engine parts, front fork parts) or the like, so-called “cores” are used. There are cores made of sand and iron (iron (Fe) or an alloy containing iron as a main component), but there is a need for deep casting of front fork parts, etc. In general, as shown in FIG. 7, a core made of iron (so-called “iron core”) 900 is used. If the iron core 900 is used in this way, although the processing shape is limited (because it is necessary to extract the core from the casting after the casting process. On the other hand, when the core is made of sand material, Since it can be removed by air or the like, a complex hollow space can be formed.) It can be used repeatedly and is environmentally friendly.

  Here, when casting, it is necessary to degas. If degassing is not performed or if the degassing effect is low, gas is stored in the mold 500, 500, and molten metal (usually aluminum alloy) does not spread, and as shown in FIG. 8, the finished (completed) casting There was a problem that a gas defect (dent) 801 occurred in 800. When the gas defect 801 occurs, as shown in FIG. 9, when the cylinder member 810 is inserted and fixed to the inside, the gas defect 801 is present, so that the casting 800 is inserted and fixed therein. The axial center with the cylinder member 810 is shifted by an angle θ and does not become a parallel state (in the case of automobile parts and motorcycle parts that require high accuracy, even if the angle θ is small, there may be a serious problem).

  In particular, when an iron core is used during a casting process involving deep casting, gas (gas generated in the mold) is likely to accumulate on the bottom surface. For this reason, as shown in FIG. 7, the iron core 900 is formed with a gas vent path Z for venting gas communicating with the bottom wall portion.

On the other hand, there is a gas venting tool for casting that uses the venturi effect to vent the gas generated in the mold (see Patent Document 1).
Japanese Unexamined Patent Publication No. 7-51795

        However, since the iron core 900 is made of an iron material, it is easy to retain heat, and in particular, it becomes a high temperature in a casting process that involves casting. For this reason, if the iron core 900 as shown in FIG. 7 is used, deep casting can be performed, but there is a problem that the solidification time of the molten metal is long and the productivity is poor. It seems that the generated gas in the mold is also heated.

  Further, in order to shorten the solidification time of the molten metal, it is preferable that the gas generated in the mold is removed as soon as possible. However, the gas venting structure of the natural exhaust method as described in Document 1 has a poor gas venting efficiency. There was a problem.

  On the other hand, the casting gas vent described in Patent Document 1 has a problem that it cannot be used for casting that requires casting, and uses a passage arranged in parallel with a cooling gas passage (passage). Since the venturi effect is obtained, there is a problem that the gas venting effect from the outermost end (bottom wall) of the casting gas venting tool cannot be sufficiently obtained. There was also a problem that the cooling effect from the inside could not be achieved.

  The present invention has been devised to solve the above-mentioned problems, and the present invention prevents the occurrence of gas defects even when it is necessary to perform a deep punching process in manufacturing a casting. Another object of the present invention is to provide a casting gas venting tool that can improve the cooling effect, shorten the solidification time, and thereby shorten the casting cycle time (tact).

(Claim 1)
In order to achieve the above object, a casting gas venting tool according to claim 1 is formed inside a hollow cylindrical iron core used for casting, and is formed in the mold from the bottom surface side of the iron core. A gas vent path for draining the generated gas (for discharging), further comprising a cooling path for reciprocating circulation of the cooling gas formed inside the iron core, The degassing path is configured to communicate with the cooling path, and performs degassing by the venturi effect using the reciprocating flow of the cooling gas in the cooling path.
According to the casting gas venting tool of claim 1 having such a configuration, the bottom surface of the iron core is formed through a gas venting path formed inside a hollow cylindrical iron core used for casting. The gas generated in the mold is extracted (discharged) from the side of the part. Further, a cooling path is formed inside the iron core, and the cooling gas reciprocates through the cooling path.
(Claim 2)
The casting gas vent according to claim 2 is the casting gas vent according to claim 1, wherein a part of the gas vent path is constituted by a return path of the cooling path.
According to the casting gas venting tool of claim 2 having such a configuration, the gas vented from the mold due to the venturi effect is operated via the cooling path in addition to the same action as the casting gas venting tool of claim 1. It is discharged outside the iron core.
(Claim 3)
The casting degassing tool according to claim 3 is the casting degassing tool according to claim 1 or 2, wherein the cooling path is outside the pipe member for path construction disposed inside the iron core. And an outer space inside the iron core, an inner space inside the pipe member for route construction, and a communication space for communicating the two spaces, and at least the outer space and the inner space. Each of the forward path and the return path, or at least one of the forward path and the return path is configured by at least the inner space and the outer space, respectively, and the gas vent path is formed on the bottom surface portion of the iron core that communicates with the cooling path. The vent hole is provided with at least the return hole of the vent hole and the cooling path.
According to the casting gas venting tool according to claim 3 having such a configuration, the same function as the casting gas venting tool according to claim 1 or 2, and further, for the path configuration disposed inside the iron core. A cooling path that is formed by an outer space outside the pipe member and inside the iron core, an inner space inside the pipe member for path configuration, and a communication space that communicates both the spaces. The cooling gas is reciprocated through the. On the other hand, the cooling gas is discharged through the vent hole and the return path of the cooling path.
According to a fourth aspect of the present invention, there is provided a casting gas venting tool according to the third aspect, wherein the forward path of the cooling path is constituted by an inner space.
According to the casting gas venting tool of claim 4 having such a configuration, since it acts in the same manner as the casting gas venting tool of claim 3, the forward path of the cooling path is constituted by the inner space. The cooling gas flows (passes) in the order of the inner space, the communication space, and the outer space.
(Claim 5)
The casting gas venting tool according to claim 5 is the casting gas venting tool according to claim 3 or 4, wherein the path-constituting pipe member is provided with a spiral blade member at least on the outer space side. .
According to the casting degassing tool of claim 5 having such a configuration, it acts in the same manner as the casting degassing tool of claim 3 or 4, and at least on the outer space side of the path-constituting pipe member. Due to the provided spiral blade member, the cooling gas flowing through the cooling path advances while spirally rotating at least in the outer space.
(Claim 6)
The casting gas vent according to claim 6 is the casting gas vent according to any one of claims 3 to 5, wherein the communication space is provided in the vicinity of the bottom surface of the iron core.
According to the casting gas venting tool of claim 6 having such a configuration, the communication space acts similarly to the casting gas venting tool according to any one of claims 3 to 5, and the communication space is a bottom surface portion of the iron core. Since it is provided in the vicinity, the cooling gas flows to the tip of the iron core.
(Claim 7)
An iron core according to a seventh aspect includes the casting gas vent according to any one of the first to sixth aspects.
According to the iron core according to claim 7 having such a configuration, the iron core operates in the same manner as the casting gas venting tool according to any one of claims 1 to 6, and is used in a casting process involving deep casting. However, the unsolidified molten metal is cooled from the inside and the gas generated in the mold is discharged.

(Claim 1)
According to the casting gas venting tool of claim 1, since the cooling path for reciprocating cooling gas is provided inside the iron core, the heat of the iron core during casting can be cooled, As a result, there exists an effect that a casting process can be shortened. In addition, since the venting effect is performed by using the reciprocating flow of the cooling gas in the cooling path by the gas venting path communicating with the cooling path, the cross-sectional area is large at the time of performing the casting process that requires deep casting. There is also an effect that it is possible to prevent the gas generated in the mold (gas generated in the mold) from remaining even at the time of performing the casting process that requires the punching process.
(Claim 2)
According to the casting gas venting tool of claim 2, in addition to the effect produced by the casting gas venting tool according to claim 1, a part of the gas venting path is constituted by the return path of the cooling path. There is an effect that it can be simplified.
(Claim 3)
According to the third aspect of the present invention, the casting gas venting tool operates in the same manner as the casting gas venting tool according to the first or second aspect. In addition, the cooling path and the venting path communicating with the cooling path can be configured with a simple mechanism. There is an effect that it can be realized.
(Claim 4)
According to the degassing tool for casting according to claim 4, in addition to the effect of the degassing tool for casting according to claim 3, further, the inner space side of the cooling path is the inflow side of the cooling gas, The heat storage of the iron core can be removed to the maximum, and the heat storage of the peripheral wall portion of the iron core can be effectively removed.
(Claim 5)
According to the casting gas venting tool of claim 5, in addition to the effect produced by the casting gas venting tool according to claim 3 or 4, the spiral blade member is provided at least on the outer space side of the pipe member for path construction. Since it is provided, the contact time between the cooling gas and the inner wall of the iron core is increased, and the cooling effect can be improved.
(Claim 6)
According to the casting gas venting tool of claim 6, in addition to the effect of the casting gas venting tool according to any one of claims 3 to 5, the communication space is provided in the vicinity of the bottom surface of the iron core. As a result, the entire iron core can be cooled.
(Claim 7)
In addition to the effect produced by the casting gas vent according to any one of claims 1 to 6, the iron core according to claim 7 has a high gas venting effect even when used in a casting process involving deep casting. It is possible to obtain the cooling effect. As a result, it is possible to prevent a gas defect from occurring in the finished casting, and to shorten the manufacturing cycle time of the casting.

  Hereinafter, an example (example) of a preferred embodiment of the present invention will be described with reference to the accompanying drawings. Of course, the following examples show only preferred examples of the present invention, and the technical scope of the present invention is not limited to such examples.

  FIG. 1 is a side sectional view of an iron core 100 according to an embodiment of the present invention. That is, the iron core 100 is of a type in which a casting gas venting tool is integrally formed, and is made of an iron material, and includes a casing portion 110, a path configuration pipe member 120, and a plug. Member 130.

  The casing unit 110 is formed in a cylindrical shape, and the path configuration pipe member 120 is disposed inside the casing unit 110 and coaxially with the casing unit 110. On the other hand, the plug member 130 is formed in a substantially cap shape, and is press-fitted (fitted) to the distal end portion 112 of the housing portion 110. Further, the outer periphery of the plug member 130 is a knurl which is a kind of a gas vent hole. A groove (substantially V-shaped groove) 130a is formed. The knurled groove 130 a is configured by a slight (small) gap formed between the outer peripheral wall of the plug member 130 and the inner peripheral wall of the press-fitting hole of the distal end portion 122 of the housing 110. For this reason, it can prevent that the molten metal before a casting structure (before solidification) escapes with the gas generated in a casting_mold | template. Of course, the shape and formation method of the vent holes for venting are not limited to those described above (knurl grooves 130a).

  The path configuration pipe member 120 is formed in a cylindrical shape, and is disposed inside the housing unit 110. For this reason, a space A (referred to as “inner space” in the present application documents (claims and specification)) A is formed inside the peripheral wall portion 121 of the pipe member 120 for path configuration. In the space (the application file of the present application (claims and specification)) outside the peripheral wall portion 121 of the path-constituting pipe member 120 and inside the peripheral wall portion 111 of the housing portion 110, “outside B) is formed.

  Further, a communication space C, which is a gap for communicating both the spaces A and B, is formed between the distal end portion 122 of the path configuration pipe member 120 and the plug member 130 (the bottom surface portion of the iron core 100). ing. The inner space A, the outer space B, and the communication space C form a cooling path Y through which the cooling gas reciprocates. As the cooling gas reciprocates in the cooling path Y, the iron core 100 is cooled, and the molten metal is also cooled, so that the solidification time can be shortened. Note that air is generally used as the cooling gas, but nitrogen and other gases may be used in addition to air. Here, the inner space A constitutes the forward path of the cooling path Y, and the outer space B constitutes the return path of the cooling path Y.

  In addition, the space B constitutes a gas venting path X for extracting (discharging) the gas generated in the mold (gas generated in the mold) from the molds 500 and 500. More specifically, when the cooling gas passes through the cooling path Y, the gas generated in the casting is drawn into the outer space B through the knurled groove 130a by the venturi effect. That is, the gas generated in the mold is removed from the molds 500 and 500. Thereafter, the generated gas in the mold flows through the outer space B together with the cooling gas, and is discharged out of the iron core 100.

  Next, the operation of the iron core 100 having the above configuration will be described with reference to FIG.

  First, as a precondition, the iron core 100 is used together with the mold 500 in a casting process involving a punching process. When the pair of molds 500, 500 are combined, the iron core 100 is also combined.

  After the iron core 100 is combined with the molds 500 and 500, the molten metal is poured into the mold inner space E. The gas generated in the molds 500 and 500 due to the molten metal is poured into the gas vent path X. Through the mold 500, 500. Here, in the casting process involving such a punching process, the place where the generated gas in the mold is stored is substantially specified around the bottom wall portion of the iron core 100 (corresponding to the plug member 130 in the first embodiment). It has been confirmed through experience. And this inventor can discharge | emit the gas generated in a casting_mold | template reliably by arrange | positioning the pipe member 120 for path | route configurations to the same central axis as the housing | casing part 110, and the pipe member for path | route structures. He focused on constructing a cooling path in a vacant area outside 120.

  Further, the cooling gas is reciprocated through the cooling path Y (specifically, the inner space A, the communication space C, and the outer space B in this order). For this reason, cooling the housing | casing part 110 can eventually cool a molten metal via the iron core 100, and can shorten the solidification time of a molten metal. In addition, the cooling path Y and the gas venting path X communicate with each other, and a part of the gas venting path X is configured by the return path of the cooling path Y, so that a venturi effect can be obtained with the reciprocating circulation of the cooling gas. Moreover, the degassing effect can be improved. In particular, the forward path of the cooling path Y is constituted by the inner space A, and this cooling path Y is isolated from the casing 110 of the iron core 100 that is at a high temperature by the path-constituting pipe member 120 and is insulative. Therefore, the cooling gas in the cold state directly hits the bottom wall portion of the iron core 100, and thereby the cooling effect of the bottom wall portion of the iron core 100 heated by the high temperature gas generated in the mold is obtained. As a result, the cooling effect of the molten metal in the vicinity of the bottom wall portion of the iron core 100 can also be enhanced. Here, the applicant knows from experience that the temperature in the vicinity of the bottom wall (most end) of the iron core 100 is the highest regardless of the location of the molten metal injection.

  More specifically, the cooling gas flows in the order of the inner space A, the communication space C, and the outer space B. Therefore, not only the front end portion of the iron core 100 having the highest temperature but also the peripheral wall portion 111. The cooling effect can be enhanced. This is because the tip of the iron core 100 is closer to the bottom of the mold than the root of the iron core 100 because the only part that is absorbed by the root of the iron core 100 is in the general casting process. The bottom wall portion of the iron core 100 is cooled to the maximum by passing a cooling gas that has not yet been warmed through the bottom wall portion. The peripheral wall 111 can also be cooled by circulating (passage) the cooling gas that is not completely warmed through the outer space B, and as a result, the temperature of the entire iron core 100 is lowered to solidify the molten metal. Time can be shortened and manufacturing time (cycle time) can be shortened.

(Second embodiment)
Next, an embodiment (second embodiment) different from the above embodiment will be described with reference to FIGS. In describing the iron core 200 of the second embodiment, the same parts as those of the iron core 100 of the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and different parts are emphasized. I will explain.

  The iron core 200 of the second embodiment includes a casing 110, a path configuration pipe member 120, and a plug member 230. The casing 110 is formed in a substantially hollow cylindrical shape, and a polygonal shape (for example, a square, a hexagon, an octagon, etc.) is formed in the plug mounting cylinder 214 provided on the bottom wall 212 of the casing 110. Etc.) is inserted (fitted), and there is a slight gap between the inner diameter of the press-fitting hole of the plug mounting cylindrical portion 214 and the polygonal shape formed on the outer diameter of the plug member 230. ing. A gas vent hole is formed between the plug member 230 and the plug mounting cylindrical portion 214. For this reason, it can prevent that the molten metal before a casting structure (before solidification) escapes with the gas generated in a casting_mold | template.

  Here, the casing 110 is configured with a plug mounting cylindrical portion 214 connected to the bottom wall outer surface portion 212b, and the path configuration pipe member 120 has the same diameter as or equal to the plug mounting cylindrical portion 214. It has a larger diameter. The outer space B constitutes the forward path of the cooling path Y, and the inner space A constitutes the return path of the cooling path Y and the gas vent path X. By configuring in this way, the cooling gas in a cold state (before warming) can be brought into contact with the peripheral wall portion 111 of the casing portion 110, and as a result, the cooling effect of the molten metal in the vicinity of the peripheral wall portion 111 is improved. can do. Moreover, since the venturi effect can be obtained, the degassing effect can also be improved.

(Third embodiment)
Next, an embodiment (third embodiment) different from the above embodiment will be described with reference to FIGS. In describing the iron core 300 of the third embodiment, the same parts as those of the iron cores 100 and 200 of the first and second embodiments are denoted by the same reference numerals, and detailed description thereof is omitted. In addition, the explanation will focus on the different parts.

  The iron core 300 according to the third embodiment includes a casing 110, a path configuration pipe member 120, and a plug member 230. Here, the pipe member 120 for path construction is provided with a spiral blade member 321 on the outer space B side, that is, on the outer peripheral surface 121b of the peripheral wall. Then, as shown in FIG. 6, the spiral blade member 321 causes the cooling gas passing through the outer space B to advance while spirally winding. Thereby, the contact time between the cooling gas and the inner surface 111a of the peripheral wall of the iron core is increased, so that the cooling effect of the molten metal can be improved.

  The present invention has been described based on the embodiments. However, it goes without saying that the above embodiments can be variously improved and modified without departing from the spirit of the present invention. These modifications are also included.

  For example, according to the above-described embodiment, the case where the casting gas venting tool is the core itself (configured integrally with the core) has been described, but of course, the present invention is not limited to this. It may be configured separately. For example, it may be of a type that can be retrofitted to a hollow core.

  Moreover, according to the said Example, although the spiral blade member 321 is provided only in the surrounding wall outer surface part 121b of the pipe member 120 for path | route structures, you may provide also in the surrounding wall inner surface part 121a side.

  Furthermore, according to the above embodiment, the cooling path Y is provided for substantially the entire length of the casing 110 of the iron core 100. However, the cooling path Y is not necessarily the longitudinal length of the casing 110 of the iron core 100 (see FIG. It may not be provided in the entire region in the (axis) direction, and may be configured to be folded back in the middle of the casing unit 110 (in other words, the communication space C is provided in the middle of the casing unit 110). In this case, it is necessary to provide a path for communicating the vent hole and the return path of the cooling path Y. However, in order to obtain the maximum cooling effect, it is preferable to provide the cooling path Y in the entire longitudinal direction of the casing 110 as in the above embodiment.

  It should be noted that the invention described in the above embodiment is described as follows so as to conform to the description of the scope of claims.

  In the iron core used at the time of casting with casting, it is formed so as to communicate with the hollow cylindrical housing portion and the inside of the housing portion and the bottom wall portion of the housing portion. A gas vent path (for extracting the gas generated in the mold) for discharging the gas generated in the mold, and a cooling path for reciprocating circulation of the cooling gas formed inside the housing portion, The iron core (a) is characterized in that the venting path is configured to communicate with the cooling path, and venting is performed by a venturi effect using a reciprocating flow of the cooling gas in the cooling path.

  In the iron core (a), the iron core (b) is characterized in that a part of the gas venting path is constituted by a return path of the cooling path.

  In the iron core (a) or (b), the cooling path is outside the path-constituting pipe member disposed inside the housing part and inside the housing part, and the The inner space of the path constituting pipe member is provided with both inner spaces, and a communication space that allows the two spaces to communicate with each other. At least the outer space and the inner space each have a forward path and a return path, or at least the inner space and the outer space. Either one of the forward path and the return path is configured by the space, and the gas vent path includes a gas vent hole formed in a bottom surface portion of the casing portion communicating with the cooling path, and at least the gas vent path. An iron core (c) comprising a hole and a return path of the cooling path.

  In iron core (c), the iron core (d) is characterized in that the forward path of the cooling path is constituted by an inner space.

  In the iron core (c) or (d), the path-constituting pipe member is provided with a spiral blade member at least on the outer space side.

  The iron core (f) according to any one of the iron cores (c) to (e), wherein the communication space is provided in the vicinity of the bottom wall portion of the casing portion.

It is side sectional drawing of the degassing tool for casting of 1st Example of this invention. It is a figure which shows a mode that cooling gas and the gas generated in a casting flow into the casting degassing tool of 1st Example. It is side sectional drawing of the degassing tool for casting of 2nd Example. It is a figure which shows a mode that cooling gas and the gas generated in a casting flow into the casting degassing tool of 2nd Example. It is side sectional drawing of the degassing tool for casting of 3rd Example. It is a figure which shows a mode that cooling gas and the gas generated in a casting flow into the casting degassing tool of 3rd Example. It is side sectional drawing of the degassing tool for casting of a prior art. It is sectional drawing of the casting (it has a gas defect) manufactured using the degassing tool for casting of a prior art. It is sectional drawing of the state which inserted and fixed the cylinder member in the said casting.

Explanation of symbols

100 Iron core (casting degassing tool of the first embodiment)
110 Case 111 (Case Part) Peripheral Wall 111a (Case Part) Peripheral Wall Inner Part 112 (Case Part) Tip Part 120 Path Constructing Pipe Member 121 (Path Constructing Pipe Member) Peripheral Wall 121a Peripheral wall inner surface portion 121b (of the path configuration pipe member) Peripheral wall outer surface portion 122 (of the path configuration pipe member) Tip portion 130 (of the path configuration pipe member) Plug member 200 Iron core (casting gas of the second embodiment) Punching tool)
212 Bottom wall portion 212b (outside of casing) Bottom wall outer surface portion 214 Plug mounting cylindrical portion 230 Plug member 300 Iron core (casting degassing tool of the third embodiment)
321 Spiral blade member 500 Mold A space (inside space)
B space (outside space)
C space (communication space)
X Degassing path Y Cooling path

Claims (7)

In a gas venting tool for casting, which is formed inside a hollow cylindrical iron core used for casting, and has a gas venting path for extracting gas generated in the mold from the bottom surface side of the iron core,
A cooling path for reciprocating circulation of cooling gas formed inside the iron core;
The gas venting path is configured to communicate with the cooling path, and performs venting by a venturi effect using a reciprocating flow of the cooling gas in the cooling path. .   The degassing tool for casting according to claim 1, wherein a part of the degassing path is constituted by a return path of the cooling path. The cooling path is an outer space inside the iron core that is disposed inside the iron core and inside the iron core, and an inner space inside the pipe member that forms the path. Both spaces and a communication space for communicating the two spaces are provided, and at least one of the outward path and the return path is configured by at least the outer space and the inner space, or at least one of the forward path and the return path is configured by at least the inner space and the outer space, respectively. Has been
The degassing path includes a degassing through hole formed in a bottom surface portion of an iron core communicating with the cooling path, and is configured by at least the degassing through hole and a return path of the cooling path. The casting gas venting tool according to claim 1 or 2.   4. The casting gas vent according to claim 3, wherein the forward path of the cooling path is constituted by an inner space.   5. The casting gas vent according to claim 3, wherein the pipe member for path construction is provided with a spiral blade member at least on the outer space side.   6. The casting gas vent according to claim 3, wherein the communication space is provided in the vicinity of the bottom surface of the iron core.   An iron core comprising the casting gas vent according to any one of claims 1 to 6.

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