JP2010131648A - Mold for gravity casting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for gravity casting, which can be inverted immediately after molten metal has been poured into the mold and prevents the molten metal from flowing out from the mold to enhance the quality of a casting. <P>SOLUTION: A pouring gate 2, a runner 3 and a riser 4 are formed in the mold 1. The pouring gate 2 is a port for supplying the molten metal 11. The runner 3 guides the molten metal 11 supplied from the pouring gate 2 into a production part 5 which is a forming space. The riser 4 is located between the runner 3 and the production part 5. The mold has a blocking member 8 which can block the runner 3 in mid-course. The mold 1 is supported by an inverting shaft 10 pivoted horizontally and is used for the gravity casting method including the inverting step in which the mold 1 is turned upside down around the inverting shaft 10. The blocking member 8 is made of a material (copper, for example) which has high heat conductivity in comparison with the material (casting sand, for example) of the mold 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for a mold used in a gravity casting method including a step of inverting a mold 180 degrees in the vertical direction during casting.

  Conventionally, a gravity casting method including a step of reversing a mold 180 degrees in the vertical direction in the middle of a casting process is known. In a gravity casting method including a general reversal process, since the molten metal begins to solidify at the same time as the molten metal is poured into the mold, it is desirable to reverse the mold 180 degrees in the vertical direction as soon as possible after the molten metal is poured. ing. Also, in order to effectively use the hot metal in gravity casting, it is desirable that the molten metal filled at the time of reversing the mold is not allowed to flow out. Conventionally, the molten metal on the surface of the gate is solidified. The mold was reversed after waiting. For this reason, the timing for performing the reversing process is delayed, which may adversely affect the quality of the cast product.

Therefore, as a technique for preventing the molten metal from flowing out of the mold, a technique for mechanically closing the molten metal supply system (that is, a gate, a runner, etc.) before the mold is inverted 180 degrees in the vertical direction is known. The technique is disclosed in Patent Document 1 shown below and is publicly known.
In the related art disclosed in Patent Document 1, before the solidification (solidification) of the cast product occurs, the closing means is moved to shut off the runner, and then the mold is inverted 180 degrees in the vertical direction. It is configured to solidify the molten metal by a gravity method.

However, in the related art disclosed in Patent Document 1, since mechanical closing means is employed, a gap must be secured in a portion that guides a metal plate made of steel or cast iron as the closing means. There was a possibility of the molten metal flowing out through the gap.
JP-A-11-320071

  The present invention has been made in view of the present situation, and in order to improve the quality of a cast product, the mold can be reversed immediately after the filling of the molten metal into the mold is completed, and the molten metal is removed from the mold. It is an object to provide a mold for gravity casting that does not flow out.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

  That is, according to claim 1, a pouring gate that is a molten metal supply port, a runner that guides the molten metal supplied from the pouring gate to a molding space, and a feeder part disposed between the runner and the molding space. And a reversing step that has a closing means capable of closing the runner in the middle of the runner, is supported by a reversing shaft that is supported in a horizontal direction, and is turned upside down around the reversing axis. The mold used in the gravity casting method has the closing means made of a material having a sufficiently high thermal conductivity as compared with the material constituting the mold.

  According to a second aspect of the present invention, the blocking means is disposed at a predetermined blocking position by replacing a filter disposed in the runner.

  As effects of the present invention, the following effects can be obtained.

  In Claim 1, it can prevent reliably that the molten metal stored in a feeder part spills out at the time of an inversion process.

  According to the second aspect of the present invention, the length of the runner can be kept equal to the conventional one, and the mold having the closing means can be made compact.

Next, embodiments of the invention will be described.
First, an overall configuration of a gravity casting mold according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic diagram showing an overall configuration of a mold according to an embodiment of the present invention, (a) a schematic side cross-sectional view showing a posture during an injection step, and (b) a schematic side cross-sectional view showing a posture after an inversion step, 2A and 2B are a schematic diagram showing an overall configuration (disassembled state) of a mold according to an embodiment of the present invention, (a) a schematic side sectional view, and (b) a schematic bottom view.

  As shown in FIGS. 1 (a) and 1 (b), a mold 1 which is a gravity casting mold according to an embodiment of the present invention is mainly formed using casting sand, and has a gate 2 and a runner. 3, the hot water supply part 4, the product part 5, etc. are formed. Further, the mold 1 is rotatably supported by the reversing shaft 10 and is reversed 180 degrees in the vertical direction with the reversing shaft 10 as an axis, and the state shown in FIG. From FIG. 1B, the posture can be changed to the state (post-inversion step).

  The gate 2 is a portion formed in a substantially bowl shape that serves as a supply port for supplying molten metal to the mold 1. The runner 3 is a flow passage formed as a portion that communicates the gate 2 and the feeder 4, and the product that is continuously provided to the feeder 4 by circulating the molten metal injected from the gate 2. It plays a role of guiding to the part 5.

  The hot water feeder section 4 is a gap formed in a portion below the product section 5 serving as a molding space in the posture at the time of the injection process shown in FIG. 1A, and communicates the runner 3 with the product section 5. It is formed as a part to do. And in the attitude | position after the inversion process shown in FIG.1 (b), the feeder part 4 is located above the product part 5, and plays the role which pushes the product part 5 with the molten metal with which the feeder part 4 was filled. To fulfill.

  A filter 6 is disposed in the middle of the runner 3 to impart resistance to the melt flowing into the feeder 4 through the runner 3 to rectify the flow of the melt, and to mix foreign matter in the melt. It plays the role of collecting the etc. and contributes to ensuring the quality of the cast product. Then, the molten metal injected from the gate 2 is supplied to the product section 5 through the runner 3, the filter 6 and the feeder section 4.

  The product part 5 is a void part that forms the product shape of the cast product that is the final product, and the molten metal injected into the product part 5 is solidified in the product part 5 to form the solidified molten metal into the product shape. It is a part to do.

  Here, the configuration of the periphery of the filter 6 will be described in more detail. As shown in FIG. 2, the mold 1 according to an embodiment of the present invention has a middle portion of the runner 3 in comparison with the diameter of the runner 3. A storage portion 9 is formed which is a portion having an inner space that is expanded in diameter and is a portion that communicates with the outside of the mold 1.

  The inner shape of the storage portion 9 in plan view (or bottom view) is formed substantially the same as the outer shape of the filter 6 in plan view, and the filter 6 can be inserted into the storage portion 9 with almost no gap. The filter 6 can be moved along the storage portion 9 inside the storage portion 9.

  In addition to the filter 6, the elastic member 7 and the closing member 8 are inserted into the storage portion 9. These members 6, 7, and 8 are inserted into the storage portion 9 in the order of the elastic member 7, the filter 6, and the closing member 8.

  The elastic member 7 is made of, for example, a metal spring member. When the members 6, 7, and 8 are inserted into the storage portion 9, the elastic member 7 is shortened relative to the filter 6 as compared with the steady state. It is set as the structure contacted in the made state. Thereby, the filter 6 is configured to be constantly urged by the elastic member 7 in a direction in which the filter 6 is removed from the storage unit 9 when inserted into the storage unit 9.

  Further, since the closing member 8 is brought into contact with the lower side of the filter 6, the filter 6 is not dropped from the mold 1 by the urging force of the elastic member 7. Thus, in the mold 1 according to an embodiment of the present invention, the elastic force is applied to the filter 6 from above by the elastic member 7 and the closing member 8 is brought into contact with the filter 6 below. The filter 6 is configured to prevent rattling in the storage portion 9.

  The closing member 8 is a plate-like member formed of a metal such as copper, for example, and the shape in plan view is formed substantially the same as the shape of the filter 6. For this reason, like the filter 6, the closing member 8 can also be inserted into the storage portion 9 with almost no gap, and moves along the internal shape of the storage portion 9 inside the storage portion 9. It is configured to be able to do.

Further, the closing member 8 in this embodiment is made of copper (thermal conductivity 398 W / () having a sufficiently large thermal conductivity as compared with casting sand (thermal conductivity of about 0.8 W / (m · k)). m · k)). For this reason, when the molten metal is brought into contact with the closing member 8, the molten metal that has come into contact can be immediately solidified.
In this embodiment, the case where copper is adopted as the material constituting the closing member 8 is illustrated, but the present invention is not limited to this, and the mold 1 is formed on the material constituting the closing member 8. A material having a sufficiently high thermal conductivity compared to the material can be appropriately selected and employed.

  Although there is a minute gap between the filter 6 and the closing member 8 and the storage portion 9 that serves as a guide when they move, the molten metal that flows out of the gap is surely Contact the closing member 8. Since the molten metal in contact with the closing member 8 is rapidly dissipated (cooled) and immediately solidified, it does not flow out of the gap, and the solidified molten metal further seals the gap. In the casting_mold | template 1 which concerns on this, it is prevented reliably that a molten metal flows out from the clearance gap formed by the closure member 8 and the accommodating part 9. FIG.

  In addition, the elastic member 7 is shortened by pushing the closing member 8 against the urging force of the elastic member 7 to shorten the elastic member 7, and the filter 6 is stored in the storage unit 9. The runner 3 can be closed by the closing member 8 by placing the closing member 8 at the position.

  In this way, by replacing the filter 6 and the closing member 8 and closing the runner 3 at the place where the filter 6 that is conventionally provided in the mold is disposed, Since it is not necessary to secure a new location, the mold 1 can be made compact.

That is, in the mold 1 according to one embodiment of the present invention, the closing member 8 is disposed at a predetermined closing position by replacing the filter 6 disposed in the runner 3. 3 is a member capable of closing 3.
With such a configuration, the length of the runner 3 can be kept equal to the conventional one, and the mold 1 having the closing member 8 serving as the closing means can be configured compactly.

  Next, the gravity casting method using the casting_mold | template 1 which concerns on one Example of this invention is demonstrated using FIG. 3 and FIG. FIG. 3 is a schematic diagram showing a gravity casting method (injection process) using a mold according to an embodiment of the present invention, (a) a schematic side sectional view showing an injection state, and (b) a schematic side sectional view showing an injection completion state. FIG. 4 is a schematic diagram showing a gravity casting method (reversing process to feeder process) using a mold according to an embodiment of the present invention, (a) a schematic side sectional view showing a reversed state, and (b) completion of reversal. It is a side surface cross-section schematic diagram which shows the subsequent hot-water supply state.

(Injection process)
As shown in FIG. 3A, in the injection process for injecting the molten metal 11 into the mold 1, the molten metal 11 is injected from the gate 2. The molten metal 11 injected from the gate 2 is supplied to the product section 5 through the runner 3, the filter 6 and the feeder section 4.

  Then, as shown in FIG. 3B, when a predetermined amount of the molten metal 11 is poured into the mold 1 and the product part 5 is filled with the molten metal 11, the supply of the molten metal 11 is stopped.

  At the same time, the closing member 8 is pushed into the housing 9 to replace the filter 6. At this time, the molten metal 11 stored in the runner 3 adjacent to the storage portion 9 rapidly dissipates (cools) and solidifies by coming into contact with the closing member 8. It is securely blocked.

(Reversing process)
As shown in FIG. 4 (a), in the reversing step of reversing the mold 1 up and down 180 degrees, as soon as a predetermined amount of molten metal 11 is injected into the mold 1 and the closing member 8 is pushed into the storage portion 9, The mold 1 is rotated around the reverse shaft 10. During this rotation, when the inclination angle of the mold 1 becomes a certain angle or more, the molten metal 11 stored in the gate 2 and the runner 3 starts to flow out naturally by the action of gravity along the inclination of the gate 2.

  At this time, in the mold 1 according to one embodiment of the present invention, the runner 3 is reliably closed by the closing member 8 and the molten metal 11 solidified in the runner 3 adjacent to the closing member 8. The hot water part 4 and the product part 5 are reliably held in a state filled with the molten metal 11. Further, the molten metal 11 filling the feeder part 4 and the product part 5 does not flow out of the mold 1 and the molten metal 11 stored in the feeder part 4 does not decrease.

That is, in the mold 1 according to an embodiment of the present invention, the gate 2 that is a supply port of the molten metal 11, and the runner 3 that guides the molten metal 11 supplied from the gate 2 to the product portion 5 that is a molding space, A hot water supply portion 4 disposed between the runner 3 and the product portion 5 is formed, and has a closing member 8 that is a closing means capable of closing the runway 3 in the middle of the runway 3 and is horizontal. A mold 1 that is supported by a reversing shaft 10 that is supported in the direction and that is used in a gravity casting method that has a reversing process that is reversed up and down around the reversing shaft 10, wherein the closing member 8 is a material ( For example, it is comprised with the raw material (for example, copper) whose heat conductivity is sufficiently high compared with cast sand.
With such a configuration, it is possible to reliably prevent the molten metal 11 stored in the feeder part 4 from flowing out during the reversing process.

(Feeding water process)
Then, as shown in FIG. 4 (b), the mold 1 is turned up and down 180 degrees, and the product portion 5 in the product portion 5 is pushed while the product portion 5 is pushed by gravity acting on the molten metal 11 in the feeder portion 4. The molten metal 11 is solidified. Then, even if the volume contracts as the molten metal 11 in the product part 5 solidifies, the molten metal 11 corresponding to the contracted volume can be replenished from the feeder part 4, and a cast product with stable quality can be obtained. Obtainable.

  At this time, in the mold 1 according to one embodiment of the present invention, the runner 3 is reliably closed by the closing member 8 and the molten metal 11 solidified in the runner 3 adjacent to the closing member 8. Even when 1 is turned up and down by 180 degrees, the molten metal 11 filling the feeder part 4 and the product part 5 does not flow out of the mold 1.

  Thus, if the mold 1 according to an embodiment of the present invention is used, the mold 1 can be reversed immediately after the filling of the molten metal 11 into the mold 1 is completed. Since the molten metal 11 that fills the product part 5 does not flow out of the mold 1, it is possible to effectively perform the hot metal feeding and improve the quality of the cast product.

The schematic diagram which shows the whole structure of the casting_mold | template which concerns on one Example of this invention, (a) Side surface schematic diagram which shows the attitude | position at the time of an injection | pouring process, (b) The side surface cross-section schematic diagram which shows the attitude | position after an inversion process. The schematic diagram which shows the whole structure (disassembled state) of the casting_mold | template which concerns on one Example of this invention, (a) Side surface schematic diagram, (b) Bottom schematic diagram. The schematic diagram which shows the gravity casting method (injection process) using the casting_mold | template which concerns on one Example of this invention, (a) Side surface schematic diagram which shows injection | pouring state, (b) Side surface schematic diagram which shows injection completion state. The schematic diagram which shows the gravity casting method (reversing process-feeder process) using the casting_mold | template which concerns on one Example of this invention, (a) Side surface schematic diagram which shows an inverted state, (b) The feeder state after completion of inversion FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mold 2 Sprue 3 Runway 4 Hot water supply part 5 Product part 6 Filter 7 Elastic member 8 Closure member 9 Storage part 10 Reverse shaft 11 Molten metal

Claims (2)

A hot water outlet that is a molten metal supply port;
A runner that guides the molten metal supplied from the gate to the molding space;
A feeder section disposed between the runner and the molding space;
Formed,
Having a closing means capable of closing the runner in the middle of the runner;
Supported by a reversing shaft that is supported horizontally,
A mold used in a gravity casting method having a reversing step that is reversed up and down around the reversing axis,
The closing means is
Constructed by a material having a sufficiently high thermal conductivity compared to the material constituting the mold,
Gravity casting mold characterized by that. The closing means is
Replaced with a filter disposed in the runner,
Disposed at a predetermined closing position;
The gravity casting mold according to claim 1, wherein:

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