JP2010172954A - Gas venting device of casting die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas venting device of a casting die, easily removable from a die, and quickly and easily maintainable, in casting work using a core. <P>SOLUTION: The gas venting device of the casting die has: a cylindrical guide member 30 set in an upper die 2, in which an upper end side is faced to an upper surface of the upper die 2 and also a lower end side is faced to a cavity 6; and a lower end 43 contacted with a core S, in which the lower end side is slidably inserted into an inside of the guide member 30, and also provided with: a venting pipe 40 provided with a flange 42 in an intermediate part; and a holder 50 having an insertion part 54 for inserting an upper end side 44 of the venting pipe 40, in which a lower end is contacted with the flange 42. The holder 50 has an exhaust port 56 for discharging gas to the upper end side, and also is provided with a fastener 53 for fastening the venting pipe 40, and a handle 52 for detaching and attaching the fastened venting pipe 40 to the guide member 30. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas vent device for a casting mold.

When casting a complex work such as a cylinder head of an internal combustion engine, the molten metal is placed in a state where a core formed by binding sand with a resin binder is placed in the cavity of the mold. It has been practiced to pour molten metal into a mold and disintegrate the core after curing to produce a workpiece.
At this time, when the high-temperature molten metal contacts the core, the resin binder is burned and gasified. When this gas fills the mold, the molten metal entrains the gas and causes defects in the nest holes and hot water. For example, the casting mold described in Patent Document 1 is for discharging the gas. A gas vent device is provided.

The gas vent device is configured by a hollow cylindrical vent pipe or the like, and is installed through, for example, the central portion of the upper mold.
The lower end portion of the vent pipe protrudes from the cavity surface of the upper mold, and comes into close contact with the core by the mold clamping operation so that the gas is surely discharged.
Note that the vent pipe moves upward relative to the mold when the lower end of the vent pipe is pushed by the core by the mold clamping operation.

Japanese Patent No. 3811277

Since the gas vent device adheres as a gas, it is desirable that the gas vent device is removed from the mold at an appropriate frequency, and maintenance such as cleaning and replacement is performed.
However, the surroundings of the mold are relatively dark with complicated lifting devices and eject pins, and maintenance is not easy due to problems such as difficulty in visually confirming the gas vent device and difficulty in entering hands.

Further, when the spear adheres to the vent pipe, it is difficult for the vent pipe to return to its original position (position protruding from the cavity surface of the upper mold) when the mold is opened. In conjunction with the operation, pressing means for pressing the upper end of the vent pipe to forcibly return the vent pipe to its original position was provided at the upper part of the mold. For this reason, the upper part of the mold has a more complicated structure, leading to a decrease in maintainability.
In addition, although the maintenance frequency is reduced by providing the pressing means, more dirt is attached to the vent pipe, and it is very difficult to remove it when performing maintenance, and much maintenance is required.

  The present invention was devised in view of these problems, and can be easily removed from a mold in a casting operation using a core, and can be easily and quickly maintained. It is an object to provide a gas vent device of a mold.

  A casting mold gas vent apparatus according to the present invention is a casting mold gas vent apparatus for discharging gas generated from a core installed in a cavity during casting to the outside of the mold. A cylindrical guide member with the upper end facing the upper surface of the mold and the lower end facing the cavity, and the lower end side is slidably inserted into the guide member. A vent pipe having a lower end portion that comes into contact with the child and having a flange portion at an intermediate portion; a holder having an insertion portion that passes through the upper end side of the vent pipe; and a lower end that comes into contact with the flange portion; The holder has a hole for discharging the gas on the upper end side, a fixing means for fixing the vent pipe, and the fixed vent pipe removed from the guide member. , A handle for which characterized by including the.

According to such a configuration, the holder including the handle is fixed to the vent pipe. Therefore, the vent pipe can be easily removed from the mold by grasping the handle and pulling up the holder.
Further, compared to the case where the holder is not fixed to the vent pipe, the lower end portion of the vent pipe easily protrudes from the mold cavity when the mold is opened due to the weight of the holder. Therefore, the pressing means of the vent pipe can be omitted, the periphery of the mold can be simplified, and the maintenance can be quickly and easily performed.
Further, since the flange portion is provided in the middle portion of the vent pipe and the flange portion is brought into contact with the lower end portion of the holder, even if the gas flows out between the guide member and the vent pipe, the vent pipe and the holder Gas will not enter the gap. For this reason, it is possible to suppress the adhesion of the spear to the inner peripheral surface of the hollow portion of the holder.

  In the gas vent device according to the present invention, in the state where the vent pipe is fixed to the holder and the lower end side of the vent pipe is inserted through the guide member, the handle extends toward the outside of the mold. It is preferable to take out.

According to such a configuration, since the handle of the holder extends outward from the mold, the gas vent device can be easily found even when working around a relatively dark mold. In addition, if the handle is extended to a position protruding to the operator side from the side (side surface) of the mold, the handle can be easily found from the side of the mold.
Even if the vent pipe rotates in the guide member due to vibration during casting, the vent pipe does not rotate greatly because the handle interferes with an adjacent member (for example, an eject pin). Therefore, since the handle can be always directed to a desired position, the position of the gas vent device can always be easily confirmed during maintenance.

  Further, in the gas vent device according to the present invention, a space is formed between the inner peripheral surface of the insertion portion of the holder and the outer peripheral surface of the vent pipe in a state where the vent pipe is fixed to the holder. Is preferred.

  According to this configuration, since the space portion is formed between the inner peripheral surface of the insertion portion of the holder and the outer peripheral surface of the vent pipe, the gas in the vent pipe is difficult to cool due to the heat insulating action of the space portion. Can be suppressed.

  Moreover, it is preferable that the said holder is comprised so that the edge part of the said vent pipe may contact | abut on the said core with the dead weight of the said holder.

  In this way, the vent pipe returns to its original position due to its own weight when the mold is opened, so that the end of the vent pipe can be reliably brought into contact with the core during mold clamping. Therefore, the pressing means of the vent pipe can be omitted, the periphery of the mold can be simplified, and the maintenance can be quickly and easily performed.

Moreover, it is preferable that the said holder is comprised so that a self-weight can be changed with the weight attached to the said holder so that attachment or detachment is possible.
The handle is configured to be detachable from the holder, and a plurality of handles are prepared with different weights, and the holder is configured to be able to change its own weight by exchanging the handle. It is preferable.

  According to such a configuration, the weight of the holder can be adjusted appropriately by adjusting the weight attached to the holder and the mass of the handle. Thereby, the vent pipe that has moved upward when the mold is clamped can be reliably moved downward when the mold is opened.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the gas vent apparatus of the casting mold which can be easily removed from a metal mold | die and can perform maintenance quickly and easily.

It is a front view of the casting die apparatus provided with the gas vent apparatus. It is sectional drawing of the AA in FIG. It is sectional drawing of a gas vent apparatus, (a) has shown the state at the time of mold clamping, (b) at the time of mold opening, (c) has shown the state at the time of a maintenance, respectively. It is sectional drawing of the gas vent apparatus which concerns on a modification.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the description, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 1, a casting mold apparatus 1 is an apparatus for casting a cylinder head, for example, and includes an upper mold 2 that can be raised and lowered, a lower mold 3 that is a fixed mold, and a right that is movable in a horizontal direction. A mold 4, a left mold 5, a front mold, and a rear mold (not shown) are provided. The cavity 6 is formed by clamping the plurality of molds.

  In the cavity 6, a plurality of cores S1, S2, S3, and S4 (hereinafter sometimes collectively referred to as “core S”) are installed in advance. The core S is formed by binding sand with a resin binder into a desired shape. In the present embodiment, the core S1 forms a space above the upper partition wall of the cylinder head. The core S2 forms a space below the upper partition wall of the cylinder head. The cores S3 and S4 form an intake passage and an exhaust passage of the cylinder head.

The upper mold 2 is fixed to a pair of support frames 7 and 7 and the support frame 7 is driven up and down by a cylinder mechanism (not shown). The support frame 7 has an eject plate 72 that supports the eject pin 71. The eject plate 72 is configured to be slidable up and down with respect to the support frame 7, and is urged upward by springs 74 and 74 installed on spring seats 73 and 73 of the support frame 7. The support frames 7 and 7 are provided with stoppers 75 and 75 to restrict the upper limit position of the eject plate 72.
The eject pin 71 is a member that separates the cast product together with the core S from the casting mold apparatus 1. The upper end side of each eject pin 71 is fixed to the lower surface of the eject plate 72. The lower end side of each eject pin 71 is slidably inserted into an eject hole (not shown) formed in the upper mold 2.

  In a state where the casting mold apparatus 1 is clamped, the eject plate 72 is in contact with the stopper 75, and the lower end portion of the eject pin 71 is in contact with the core S1. Above the casting mold apparatus 1, pressing members 76, 76 are installed. When the casting mold apparatus 1 is opened, the stoppers 77, 77 provided on the upper part of the eject plate 72 come into contact with the pressing members 76, as the upper mold 2 is raised, and the eject plate 72 and the eject pin 71 are connected to the spring 74. It is designed to push down against the spring force. Thereby, the lower end part of the eject pin 71 protrudes from the lower surface of the upper mold 2, and the cast cylinder head and the core S can be separated from the upper mold 2.

The lower mold 3 has an injection hole (not shown) for filling the cavity 6 with molten metal from below. The right mold 4 and the left mold 5 have gas vents 4a and 5a and gas passages 4b and 5b for extracting gas generated from the cores S3 and S4, respectively. The upper mold 2 includes gas vents 2a and 2a and gas passages 2b and 2b for discharging gas from the core S1.
The gas vents 2a, 4a, 5a are directly open on the surfaces of the cores S1, S3, S4.

Further, the upper mold 2 includes a gas vent device 10 for discharging gas from the core S2. The gas vent device 10 is configured to be detachable from the upper mold 2 in order to facilitate maintenance.
The gas vent device 10 includes a cylindrical guide member 30, a vent pipe 40, and a holder 50.

As shown in FIG. 2, the guide member 30 is a member that guides the slide of the vent pipe 40, and is fitted into an attachment hole 21 that is formed through the upper mold 2 in the vertical direction.
The guide member 30 has a cylindrical shape, for example, and has a guide hole 31 formed so as to penetrate in the axial direction. The upper end side of the guide hole 31 communicates with the upper surface of the upper mold 2, and the lower end side of the guide hole 31 communicates with the cavity 6. The guide member 30 has an annular locking portion 32 protruding in the radial direction at the upper end.
The locking portion 32 is locked to a step portion 21 a formed at the upper end portion of the mounting hole 21 in a state where the guide member 30 is installed on the upper mold 2. Further, the lower end portion 30a of the guide member 30 protrudes from the lower surface (cavity surface) of the upper die 2 and is flush with the lower surface of the core S1 when the guide member 30 is installed on the upper die 2. . That is, the lower end 30a of the guide member 30 penetrates the core S1.

The vent pipe 40 is a pipe that discharges the gas generated from the core S <b> 2 to the outside of the mold, and is slidably installed in the guide hole 31 of the guide member 30.
The vent pipe 40 is a metal member having a cylindrical shape, for example, and has a gas vent hole 41 penetratingly formed in the axial direction. The vent pipe 40 has an annular flange portion 42 protruding in the radial direction at an axial intermediate portion. The flange portion 42 regulates the insertion length of the vent pipe 40 with respect to the guide member 30 by contacting the upper end portion of the guide member 30.

The lower half (lower end side) 43 of the vent pipe 40 is slidably inserted into the guide hole 31 of the guide member 30. The total length L1 of the lower half 43 of the vent pipe 40 (that is, the length from the lower surface of the flange portion 42 to the lower end portion 40a of the vent pipe 40) is from the upper surface of the upper mold 2 in a state where the casting mold apparatus 1 is clamped. It is set larger than the length L2 to the upper surface of the core S2.
The lower end portion 40 a of the vent pipe 40 protrudes below the lower end portion 30 a of the guide member 30 in a state where the vent pipe 40 is installed on the guide member 30. Further, the lower end portion 40a of the vent pipe 40 is in contact with the upper surface of the core S2 during mold clamping.
The upper half (upper end side) 44 of the vent pipe 40 is inserted into a holder 50 described later.

The holder 50 is a member that is held by an operator when the vent pipe 40 is inserted into and removed from the guide member 30. The holder 50 also has a function of returning (lowering) the vent pipe 40 to its original position by its own weight when the mold is opened. The holder 50 includes a holder main body 51, a handle 52, and a fixture 53. The holder 50 is attached to the upper half 44 of the vent pipe 40.
The mass of the holder 50 can be appropriately set by changing the member thickness and material in consideration of the frictional resistance between the guide member 30 and the vent pipe 40 and the frequency of maintenance.

The holder main body 51 is a thick metal member having a cylindrical shape, for example, and has an insertion portion 54 that is a hole for inserting the upper half portion 44 of the vent pipe 40.
The insertion part 54 is, in order from the lower end side, the same diameter part 54a formed to be substantially the same diameter as the outer diameter of the vent pipe 40, the large diameter part 54b formed to be larger than the outer diameter of the vent pipe 40, It is composed of
The same diameter portion 54 a is a hole for fitting into the vent pipe 40, and opens to the lower end portion 51 a of the holder main body 51. A space portion K is formed between the inner peripheral surface of the large diameter portion 54 b and the outer peripheral surface of the vent pipe 40.
An exhaust hole 56, which is a hole for discharging gas rising from the vent pipe 40, is formed in the upper end portion 51 b of the holder body 51. The exhaust hole 56 is formed to have a smaller diameter than the outer diameter of the vent pipe 40 and communicates with the large diameter portion 54b.
The lower end portion 51 a of the holder main body 51 is in contact (desirably surface-attached) with the upper surface of the flange portion 42 of the vent pipe 40 in a state where the vent pipe 40 is inserted into the holder main body 51. Therefore, even if the gas flows out from between the guide member 30 and the vent pipe 40, it is difficult for the gas to enter the insertion portion 54.

The handle 52 is a rod-shaped metal member that extends obliquely upward from the outer peripheral surface of the holder body 51. The proximal end side 52 a of the handle 52 is fixed to the outer peripheral surface of the holder main body 51 by, for example, welding. Further, the distal end side 52b of the handle 52 is bent substantially horizontally.
The distal end side 52b of the handle 52 protrudes from the side surface 2c of the upper mold 2 when the handle 52 is placed on the upper mold 2 with the operator 52 facing the operator.

  The fixture 53 is a rod-shaped member for fixing the vent pipe 40 to the holder 50. A male screw is formed on one end side of the fixture 53. The fixture 53 is inserted into a screw hole 55 formed so as to penetrate from the outer peripheral surface of the holder main body 51 to the same diameter portion 54a. A knob portion 53 b is formed on the other end side of the fixture 53. The fixture 53 is configured to advance and retract with respect to the vent pipe 40 inserted into the holder main body 51 when the operator picks and rotates the knob portion 53b.

  Next, the operation of the gas vent device 10 will be described with reference to FIG. 3 (FIGS. 1 and 2 as appropriate). FIG. 3 is a cross-sectional view of the gas vent device, where (a) shows a state during mold clamping, (b) shows a state when the mold is opened, and (c) shows a state during maintenance.

  For example, when casting a cylinder head using the casting mold apparatus 1, first, the casting mold apparatus 1 is opened and the core S is installed on the lower mold 3. The gas vent device 10 is set in the mounting hole 21.

  As shown in FIG. 3A, when the casting mold apparatus 1 is clamped, the lower end portion 40a of the vent pipe 40 comes into contact with the upper surface of the core S2. At this time, the total length L1 (see FIG. 2) of the lower half 43 of the vent pipe 40 is set to be larger than the length L2 (see FIG. 2) from the upper surface of the upper mold 2 to the upper surface of the core S2 at the time of clamping. Therefore, as the upper mold 2 is lowered, the vent pipe 40 and the holder 50 move relatively upward with respect to the upper mold 2. As a result, the lower end portion 40a of the vent pipe 40 is surely brought into contact with the upper surface of the core S2, and the flange portion 42 is separated from the upper mold 2 (more specifically, the guide member 30).

In this state, the cylinder head is cast by filling the cavity 6 from below with an injection hole (not shown) of the lower mold 3. The resin binder contained in the core S is combusted and gasified by the heat of the molten metal, and is discharged out of the mold through the gas vent device 10 and the other gas vents 2a, 4a, and 5a.
At this time, since the space K is formed between the inner peripheral surface of the large-diameter portion 54b of the gas vent device 10 and the outer peripheral surface of the vent pipe 40, it is difficult for the gas in the vent pipe 40 to be cooled, and the sanitization occurs. It is suppressed.

  After the molten metal has cooled and solidified, the casting mold apparatus 1 is opened as shown in FIG. At this time, since the vent pipe 40 is configured to be slidable with respect to the guide member 30, the vent pipe 40 slides downward relative to the upper mold 2 due to the weight of the holder 50 as the upper mold 2 is raised. The vent pipe 40 is stopped by the lower surface of the flange portion 42 coming into contact with the upper end of the guide member 30 and returned to the original position.

As the casting operation is repeated, the amount of dirt adhering to the vent pipe 40 and the guide member 30 increases, and the vent pipe 40 becomes difficult to slide. Therefore, the operator needs to perform maintenance (cleaning or replacement) at a predetermined frequency.
Therefore, the operator removes the vent pipe 40 from the upper mold 2 by holding the handle 52 of the holder 50 and pulling it upward as shown in FIG. At this time, the handle 52 of the holder 50 is extended toward the outside of the casting mold apparatus 1, and the tip end side 52 b protrudes from the side surface 2 c of the upper mold 2. Can be found.

The operator separates the holder 50 and the vent pipe 40 by loosening the fixing tool 53, and fixes the other vent pipe 40 to which the spear does not adhere to the holder 50. Note that the removed vent pipe 40 removes the adhering dust until the next replacement.
The operator cleans the guide hole 31 of the guide member 30 with a wire brush or the like after extracting the vent pipe 40.
When the replacement and cleaning are completed, the operator grasps the handle 52 of the holder 50 and inserts the lower half 43 of the vent pipe 40 into the guide hole 31 of the guide member 30 again. Thereby, the maintenance work is completed.

  As described above, according to the gas vent device 10 according to the present embodiment, the holder 50 including the handle 52 is fixed to the vent pipe 40. Therefore, by pulling the holder 50 while holding the handle 52, the upper mold The vent pipe 40 can be easily removed from 2.

  Specifically, since the handle 52 of the holder 50 extends outward from the casting mold apparatus 1, the gas vent apparatus 10 can be easily found even when working around the relatively dark casting mold apparatus 1. can do. In addition, since the front end side 52b of the handle 52 extends to a position protruding to the operator side from the side surface 2c of the upper mold 2, the operator can observe from the side of the casting mold apparatus 1, The handle 52 can be easily found.

  Further, even if the vent pipe 40 is rotated in the guide member 30 due to vibration during casting, the handle 52 interferes with the eject pin 71 disposed adjacent to the vent pipe 40, so that the vent pipe 40 does not rotate greatly. Therefore, since the handle 52 can be always directed to a desired position, the position of the gas vent device 10 can always be easily confirmed during maintenance.

  Further, compared to the case where the holder 50 is not installed on the vent pipe 40, the lower end portion 40a of the vent pipe 40 is easily returned to the original position when the mold is opened due to the weight of the holder 50. Therefore, the conventional vent pipe pressing means (see Patent Document 1) can be omitted, the surroundings of the gas vent device 10 can be simplified, and maintenance can be performed quickly and easily. .

  Moreover, since the flange part 42 was provided in the intermediate part of the vent pipe 40, and the flange part 42 was closely_contact | adhered to the lower end part 51a of the holder main body 51, gas flowed out between the guide member 30 and the vent pipe 40 temporarily. Even so, gas does not enter the insertion portion 54 of the holder main body 51. Therefore, it is possible to suppress the adhesion of the spear to the inner peripheral surface of the insertion portion 54 of the holder main body 51.

  Further, since the space portion K is formed between the inner peripheral surface of the large diameter portion 54b and the outer peripheral surface of the vent pipe 40, the vent pipe 40 becomes difficult to cool due to the heat insulating action of the space portion K, and the gas Can be prevented from cooling down and becoming sanitized.

Next, a gas vent device 10 according to a modification will be described with reference to FIG.
As shown in FIG. 4, the gas vent device 20 according to the modified example is different from the gas vent device 10 described above in that the handle 52 of the holder 50 has a weight W for adjusting the weight of the holder 50. Yes.

The weight W is, for example, a metal member formed in a short column shape, and includes a through hole Wa for inserting the handle 52 in the center. The weight W is detachably attached to the holder 50 by inserting the through hole Wa through the handle 52. The shape and material of the weight W are not particularly limited.
In the gas vent device 20 according to the modification, a plurality of weights W are prepared, and the mass (self-weight) of the holder 50 can be adjusted by increasing or decreasing the number attached to the handle 52.

  According to such a configuration, by adjusting the number of weights W attached to the holder 50, the vent pipe 40 and the holder 50 that are relatively moved upward during mold clamping are reliably moved downward when the mold is opened by the weight of the holder 50. be able to.

  As mentioned above, although embodiment of this invention was described in detail with reference to drawings, this invention is not limited to this, In the range which does not deviate from the main point of invention, it can change suitably.

For example, in the above-described modification, the weight of the holder 50 is adjusted by changing the number of weights W. However, the present invention is not limited to this. For example, the handle 52 is attached to the holder main body 51. While being configured to be detachable, a plurality of handles 52 having different thicknesses and lengths may be prepared.
According to this configuration, the mass of the holder 50 can be changed by exchanging the handle 52 with a different mass.

  In the present embodiment, the screw-type fixture 53 has been described as an example of the fixing means. However, the present invention is not limited to this, and for example, a so-called plunger may be used.

  Further, in the present embodiment, the description has been given taking the casting of the cylinder head as an example, but it goes without saying that the present invention may be applied to the case of casting other than the cylinder head.

DESCRIPTION OF SYMBOLS 1 Casting die apparatus 10 Gas vent apparatus 30 Guide member 40 Vent pipe 42 Flange part 50 Holder 52 Handle 53 Fixing tool (fixing means)
K space part S core

Claims (6)

A gas vent device for a casting mold for discharging gas generated from a core installed in a cavity during casting to the outside of the mold,
A cylindrical guide member incorporated in the mold, with the upper end facing the upper surface of the mold and the lower end facing the cavity;
A vent pipe that slidably inserts a lower end side into the guide member, has a lower end portion that comes into contact with the core, and includes a flange portion in an intermediate portion,
A holder having an insertion portion for inserting the upper end side of the vent pipe, and a lower end abutting the flange portion; and
The holder includes a hole for discharging the gas at an upper end side, a fixing means for fixing the vent pipe, and a handle for attaching and detaching the fixed vent pipe to the guide member. A gas vent device for a casting mold characterized by comprising:   2. The handle extends toward the outside of the mold in a state where the vent pipe is fixed to the holder and a lower end side of the vent pipe is inserted into the guide member. 2. A gas vent device for a casting mold according to 1.   The space part is formed between the inner peripheral surface of the said insertion part of the said holder, and the outer peripheral surface of the said vent pipe in the state which fixed the said vent pipe to the said holder. Item 3. A gas vent device for a casting mold according to Item 2.   4. The gas vent device for a casting mold according to claim 1, wherein the holder abuts an end portion of the vent pipe against the core by the weight of the holder. 5. .   5. The gas vent device for a casting mold according to claim 1, wherein the holder is configured so that its own weight can be changed by a weight that is detachably attached to the holder. 6. . The handle is configured to be detachable with respect to the holder, and a plurality of handles are prepared with different weights,
The gas vent device for a casting mold according to any one of claims 1 to 4, wherein the holder is configured to be able to change its own weight by exchanging the handle.

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