JP3065221B2 - Core molding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core molding method for molding a sand core by filling molding sand into a cavity of a clamped mold.

[0002]

2. Description of the Related Art A related art relating to a conventional core molding method is described in Japanese Patent Application Laid-Open No. 60-238061, and FIG. 6 shows an outline of a core molding apparatus for carrying out the method. Have been. The core molding apparatus 1 is a vertically split top blow type core molding apparatus for molding a hollow sand core, and mold clamping is performed by moving a movable mold 4 with respect to a fixed mold 2. Will be Here, the mold clamping is performed by pressing the fixed vise 2b and the movable vise 4b attached to the tie bar 6 with both the dies 2 and 4 therebetween. Further, casting sand injection ports (not shown) are formed on the upper surfaces of the dies 2 and 4. Above the dies 2 and 4, a blow head 8 for injecting molding sand into the casting sand blowing ports of the dies 2 and 4 is provided. The molds 2 and 4 which have been clamped together with the mold clamping mechanisms such as the tie bar 6, the fixed vice 2b, and the movable vise 4b are moved along the center line by the action of a rotating mechanism (not shown) when sand is discharged. It can rotate about 180 ° around C. further,
After the mold is opened, the fixed mold 2 and the fixed vise 2b can rotate about 90 ° counterclockwise in the figure with respect to the center line C by the action of a reversing mechanism (not shown).

[0003] When a hollow sand core is to be molded by the core molding apparatus 1, first, the molds 2 and 4 are clamped, and the molding sand is blown from the blow head 8 to the casting sand injection ports of the molds 2 and 4. Is blown. Thus, the molding sand is filled in the cavities 3 of the dies 2 and 4. The dies 2 and 4 are heated to a predetermined temperature. After a lapse of a predetermined time from this state, the rotating mechanism is operated, and the dies 2 and 4 are rotated about the center line C by about 180 ° together with the mold clamping mechanisms such as the tie bar 6, the fixed vise 2b, and the movable vise 4b. I do. As a result, the molding sand blowing ports of the dies 2 and 4 are directed downward, and unnecessary molding sand is discharged from the cavity 3. The molding sand is solidified and adheres to the wall surface of the cavity 3 with a predetermined thickness. Next, molds 2 and 4 are again used.
Is rotated about the center line C by about 180 ° together with the mold clamping mechanism to return to the original state. Then, from this state, the molding sand is further fired for a certain period of time to form a hollow core. When the hollow core is formed in this way, the molds 2 and 4 are opened, and further, the stationary mold 2 is rotated about 90 ° by the reversing mechanism so that the cavity surface faces upward. The hollow core of the product is removed.

[0004]

However, in the conventional core molding apparatus 1, the dies 2 and 4 are continuously fixed from the fixed vise 2 until the mold is opened after the mold is clamped.
b, and are pressed from both sides by a mold clamping mechanism such as the movable vise 4b. Therefore, one mold clamping mechanism is required for one set of dies 2 and 4. Further, when the molds 2 and 4 are rotated during sand removal, the molds 2 and 4 are rotated.
4 must be rotated together with a mold clamping mechanism such as the fixed vise 2b and the movable vise 4b. For this reason, the rotation mechanism of the core molding apparatus 1 becomes large-scale, and the equipment becomes large, and the installation space is required widely. Further, since the movable mold 4 is configured to clamp the mold by traversing, it is necessary to consider a positional shift due to gravity. For this reason, in order to improve the positional accuracy, it is necessary to take measures such as increasing the thickness of the tie bar 6 and the like, and the device also becomes large.
The technical problem of the present invention is to enable the mold to be clamped by a member different from the mold clamping mechanism after the mold is clamped, so that the mold can be detached from the mold clamping mechanism so that it can be handled independently and a rotating mechanism or the like can be used. To reduce the number of mold clamping mechanisms so that one mold clamping mechanism can handle multiple dies, and make the overall equipment compact. Another object of the present invention is to prevent the mold from shifting due to gravity by allowing the mold to be clamped from above and below.

[0005]

[Means, actions, and effects for solving the problem]

[Means for Solving the Problems According to Claim 1] The above-mentioned problems are solved by a core molding method having the following features. That is, the core molding method according to claim 1 is a core molding method for molding a sand core by filling molding sand into a cavity of the mold from above the clamped mold and forming the sand core. The mold is clamped from above and below by the mold clamping mechanism, and the clamped mold is clamped, the clamped mold is removed from the mold clamping mechanism and rolled independently, and the molding sand is blown into the mold. Positioning the mold so that the mouth faces upward. [Operation of the invention described in claim 1] According to the present invention,
Since the mold is clamped from above and below, there is no displacement of the mold due to gravity as in the conventional method of clamping the mold from the lateral direction. For this reason, it is not necessary to consider the displacement of the mold due to gravity, and the mold clamping mechanism can have a simple structure. Further, since the mold is clamped after the mold is clamped, it can be separated from the mold clamping mechanism. For this reason, the mold can be rolled independently of the mold clamping mechanism, and the rolling mechanism of the mold can be reduced in size. [Effect of the invention described in claim 1] According to the present invention,
Since the mold clamping mechanism and the mold rolling mechanism can be miniaturized, the core molding apparatus becomes compact, and the vertical occupation area reduces the occupied area.

According to a second aspect of the present invention, there is provided a core molding method for molding a sand core by filling molding sand into a cavity of a clamped mold. The method includes the steps of clamping the clamped mold, removing the clamped mold from the mold clamping mechanism, transporting the clamped mold to another position, and filling the molding sand. [Operation of the invention described in claim 2] According to the present invention,
Since the mold is clamped after the mold is clamped, it can be removed from the mold clamping mechanism. Then, the mold removed from the mold clamping mechanism is transported to another position, where the molding sand is filled. On the other hand, the mold clamping mechanism only needs to operate at the time of mold clamping, so after clamping and sending out the first mold,
Subsequently, the next mold can be clamped. Therefore, for example, when the next die is being clamped, the first die transported to another position can be filled with molding sand. That is, according to the present invention, even in an operation using a plurality of dies, only one mold clamping mechanism is required. [Effects of the Invention According to Claim 2] Conventionally, when operating using a plurality of dies, the number of mold clamping mechanisms and the like were necessary, but according to the present invention, Since only one fastening mechanism is required, the area occupied by the equipment can be reduced, and the equipment cost can be reduced.

[0007]

【Example】

[First Embodiment] A core molding method according to the present embodiment will be described below with reference to FIGS. Here, FIG. 1 is a front view of a core molding apparatus 10 used when performing the core molding method according to the present embodiment, and FIG.
0 is a side view. The following description will be made with the width direction of the core molding apparatus 10 as the X-axis method, the depth direction as the Y-axis direction, and the height direction as the Z-axis direction.

The core molding apparatus 10 includes a lifting cylinder 12 fixed to the center of a base 11. The elevating cylinder 12 is positioned parallel to the Z axis, and a die fixing member 13 is attached to the tip of a piston rod 12p. Four guide rods 13r extending downward are fixed to the lower surface of the mold fixing member 13, and these guide rods 13r are inserted through four sets of guide members 11h provided on the base 11. . With this structure, when the elevating cylinder 12 is operated,
The mold fixing member 13 moves up and down while being held horizontally.
Further, a first clamp 13k for fixing the lower mold 14 at a fixed position on the upper surface of the mold fixing member 13 is mounted on the upper side of the mold fixing member 13 on both sides in the X-axis direction. further,
An extruding cylinder 13y used when the sand core product (not shown) is pushed out of the cavity wall surface of the lower mold 14 after the sand core is formed, is attached to the mold fixing member 13.

Above the mold fixing member 13, a mold turning frame 15 is provided. Mold turning frame 1
Reference numeral 5 denotes a member that clamps and holds the clamped upper mold 16 and lower mold 14, and is a gate-shaped frame body 15m.
And a second clamp 15k for fixing the upper mold 16 to the frame main body 15m, and a third clamp 15s for fixing the lower mold 14 to the frame main body 15m. Here, a casting sand injection port (not shown) is formed at the joint of the upper mold 16 and the lower mold 14 (hereinafter, referred to as the molds 14 and 16) which have been clamped.

Rotation mechanisms 15j are coaxially provided on both side surfaces of the frame main body 15m, and the frame main body 15m is rotatably supported by the apparatus frame 11m via the rotation mechanisms 15j. . Also, one rotating mechanism 1
The rotation torque from the turning motor 15t is added to 5j. With this structure, when the turning motor 15t is operated, the frame main body 15m turns around a virtual center line C parallel to the X axis by a predetermined angle.

A blow head 1 for blowing molding sand into the dies 14 and 16 is provided above the die turning frame 15.
8 are provided. The blow head 18 is mounted on the upper part of the apparatus stand 11m via a positioning cylinder 18y, and can be lowered to a position where it is connected to the dies 14, 16 by the operation of the positioning cylinder 18y.

Next, the core molding method according to the present embodiment will be described while explaining the operation of the core molding apparatus 10 described above. First, the upper mold 16 and the lower mold 14 are set on the mold fixing member 13 in a combined state, and the lower mold 14 is fixed to the mold fixing member 13 by the first clamp 13k. Next, the mold fixing member 13 is raised by the operation of the elevating cylinder 12, and the upper mold 16 and the lower mold 14 are pushed up to the position of the mold turning frame 15 as shown in FIG. . Then, when the upper mold 16 and the lower mold 14 have risen to a predetermined position, the lifting cylinder 12 stops, and the upper mold 16 is fixed to the frame main body 15m by the second clamp 15k. The mold 14 is fixed to the frame body 15m by the third clamp 15s. As a result, the molds 14 and 16 are clamped in a clamped state, and are held by the mold turning frame 15.

In this state, the first clamp 13k of the mold fixing member 13 is removed from the lower mold 14, and the elevating cylinder 12 is actuated in a direction for accommodating the piston rod 12p, thereby lowering the mold fixing member 13 to the lower limit. Descend to the position. next,
When the swing motor 15t is driven, the mold swing frame 15 is rotated by about 90 °, so that the casting sand blowing port provided at the joint between the molds 14 and 16 faces upward. In this state, when the positioning cylinder 18y operates, the blow head 18 is lowered, and the blow head 18 is connected to the casting sand blowing ports of the dies 14, 16.

Then, the mold 1 is moved from the blow head 18 to the mold 1.
Foundry sand is blown into the cavities 4 and 16. As described above, since the molding sand is blown downward from above, the filling rate of the molding sand is improved. The dies 14, 16
Are heated to a predetermined temperature in advance. When the molding sand is filled in the cavities of the molds 14 and 16 in this manner, the blow head 18 rises and separates from the molds 14 and 16, and then the turning motor 15t operates to turn the mold turning frame 15. Rotates about 180 °. Thereby, the mold 1
The casting sand injection ports of 4, 16 are directed downward, and the mold 14,
Unnecessary molding sand is discharged from the 16 cavities. When sand is removed, the mold turning frame 15 is
The metal molds 14 and 16 are rotated by 90 ° and returned to the original state, that is, the upper mold 16 and the lower mold 14 are vertically stacked, and firing is performed.

Next, the elevating cylinder 12 operates in the direction in which the piston rod 12p extends, and moves up to a position where the mold fixing member 13 contacts the lower mold 14. Next, lower mold 1
4 is fixed to the mold fixing member 13 by the first clamp 13k, and the third clamp 1 of the frame body 15m is further fixed.
5s is opened and the lower mold 14 is removed from the frame main body 15m. Then, in this state, the elevating cylinder 12 operates to lower the mold fixing member 13. As a result, the upper mold 16 remains in the lower
And the sand core product (not shown) is a mold fixing member 1
3, the molds 14 and 16 are opened. In this way, when the mold fixing member 13 is lowered to the lower limit position, the extruding cylinder 13y operates and the core product is pushed out of the lower mold 14, and the core product is taken out. After the product is taken out, the lower die 14 is moved upward by the upper die fixing member 13 being moved up again.
The mold is clamped according to. That is, the mold fixing member 13, the lifting cylinder 12, and the like correspond to the mold clamping mechanism of the present invention.

As described above, according to the core molding method according to the present embodiment, since the molds 14 and 16 are clamped from the vertical direction, gravity is used as in the conventional method of clamping the molds from the lateral direction. No mold displacement occurs. For this reason, it is not necessary to consider the displacement of the mold due to gravity, and the mold clamping mechanism can have a simple structure. Furthermore, since the device is of a vertical type, the area occupied by the device is reduced. Also, since the molds 14 and 16 are clamped after the mold is clamped,
It can be separated from the mold clamping mechanism. For this reason, the dies 14, 16 can be rolled independently of the mold clamping mechanism, and the rolling mechanism of the dies can be reduced in size.

[Second Embodiment] Next, a core molding method according to a second embodiment of the present invention will be described with reference to FIGS. Here, FIG. 3 is a plan view of the core molding apparatus 20 used when performing the core molding method according to the present embodiment, and FIG. 4 is a view taken in the direction of arrows IV-IV in FIG. Is VV in FIG.
It is an arrow view. As shown in FIG. 3, the core molding apparatus 20 includes a mold clamping station T in which a mold clamping mechanism 30 is installed, and a blowing station B that blows molding sand into the clamped dies 24 and 26. Is provided. Here, in the blowing station B, two sets of blowing mechanisms 40 and two sets of mold turning mechanisms 50 are installed. Note that the mold clamping directions of the dies 24 and 26 are X
The axial direction, the direction in which the mold clamping station T and the blowing station B are arranged in the Y-axis direction, and the height direction in the Z-axis direction are described below.

As shown in FIGS. 3 and 4, the mold clamping mechanism 30 is a mechanism for clamping the movable mold 26 to the fixed mold 24 from the lateral direction (X-axis direction). A fixed vice 34 and a movable vise 36 attached to 35
The two molds 24 and 26 are clamped from both sides in the X-axis direction and pressed to clamp the molds. Here, a first clamp 34k is mounted on the fixed vise 34, and the fixed mold 24 is fixed to the fixed vise 3 by the first clamp 34k.
4 at a fixed position. Further, a second clamp 36k is mounted on the movable vise 36, and the movable mold 26 is attached to a fixed position of the movable vise 36 by the second clamp 36k. Further, the movable mold 26 is provided with a third clamp 26c for clamping the movable mold 26 and the fixed mold 24 in a clamped state. Note that the movable mold 26 and the fixed mold 24 (hereinafter, referred to as mold 2)
4, 26) is formed with a casting sand blowing port.

The mold clamping mechanism 30 is provided with a reversing cylinder (not shown) for reversing the fixed mold 24 and the fixed vise 34 by about 90 ° when the mold is opened. Further, the loading / unloading wheels 38 are provided on the floor of the mold clamping mechanism 30.
(See FIG. 5). The loading / unloading wheel 38 is Y
A plurality of wheels arranged horizontally in the axial direction. The dies 24, 26 clamped by the third clamp 26c are conveyed to the blowing station B, and the dies 24, 26 that have been fired at the blowing station B are received. It is for.

In the blowing station B, FIG.
As shown in FIG. 5, a rail 60 is laid in the X-axis direction, and a cart 62 is installed on the rail 60. Further, two sets of mold turning mechanisms 50 are positioned on the carriage 62. The mold turning mechanism 50 includes:
This is a mechanism for receiving and holding the dies 24, 26 sent from the mold clamping mechanism 30 and rotating the dies 24, 26 at the time of sand removal, as shown in FIG. A turning frame 52 having a substantially circular shape and a turning roller 54 for turning the turning frame 52 around an axis are provided. The turning frame 52 is provided with a mold storage space 52s having a U-shape in a side view.
A loading / unloading wheel 52t for loading / unloading the dies 24, 26 is provided on the 2s floor. The loading / unloading wheel 52t
Is at the same level as the carry-in / out wheel 38 of the mold clamping mechanism 30 in the state where the mold is positioned horizontally.

4 and 5 on both sides of the blowing station B in the X-axis direction at a position higher than the mold turning mechanism 50.
As shown in FIG. 2, a blowing mechanism 40 is provided. The blowing mechanism 40 includes a blow head 42 for blowing molding sand into the dies 24 and 26,
2 is provided with a positioning cylinder 44 for positioning the molding sand 2 and a molding sand tank 46 for storing molding sand. Here, as shown in FIG. 3, when the cart 62 is located at the right end, the dies 24 and 26 held by the right die turning mechanism 50 are positioned right below the right blow head 42. Positioned. On the other hand, the left mold turning mechanism 50 is positioned at the center of the blowing station B, and the carry-in / out wheels 52t of the turning frame 52 are continuous with the carry-in / out wheels 38 of the mold clamping mechanism 30. When the bogie 62 is located at the left end, the left die turning mechanism 50
Are positioned just below the blow head 42 on the left side. On the other hand, the right mold turning mechanism 50 is positioned at the center of the blowing station B, so that the carry-in / out wheels 52t of the turning frame 52 are continuous with the carry-in / out wheels 38 of the mold clamping mechanism 30.

Next, the core molding method according to the present embodiment will be described while explaining the operation of the core molding apparatus 20 described above. First, the movable mold 26 attached to the movable vise 36 traverses the fixed mold 24 attached to the fixed vise 34 of the mold clamping mechanism 30 to perform mold clamping. When the mold is clamped, the third clamp 26 attached to the movable mold 26
The movable mold 26 and the fixed mold 24 are clamped by c. Next, the first clamp 34k of the fixed vice 34
Is opened and the fixed mold 24 is removed from the fixed vise 34,
Further, the second clamp 36k of the movable vise 36 is opened, and the movable mold 26 is removed from the movable vise 36. Next, the molds 24 and 26 are held by the loading / unloading wheels 38 while being clamped by the third clamp 26c.
Transported to 0.

At this time, if the blowing station B
3 is positioned at the right end as shown in FIG. 3, the dies 24 and 26 are received by the left die turning mechanism 50. When the reception of the molds 24 and 26 is completed, the carriage 62 is moved to the left end,
The dies 24 and 26 are positioned at a position H indicated by a two-dot chain line in FIG.
Is positioned. When the carriage 62 is moved to the left end, the carry-in / out wheel 52t of the right mold turning mechanism 50 is connected to the carry-in / out wheel 38 of the mold clamping mechanism 30. In this state, the left blow head 42 descends and is connected to the casting sand blowing ports of the dies 24 and 26 positioned at the position H indicated by the two-dot chain line in FIG.
Molding sand is blown into the cavities 4 and 26.

When a predetermined period of time has elapsed after the molding dies 24 and 26 have been filled with molding sand, the blow head 42 rises and is separated from the dies 24 and 26, and further, the turning frame 52 of the die turning mechanism 50 is moved. By rotating about 180 °, the dies 24, 26
Of the casting sand is directed downward. As a result, unnecessary molding sand is discharged from the cavity, and the molding sand is solidified and adheres to the wall surface of the cavity with a predetermined thickness. When the sand is removed, the revolving frame 52 rotates again by about 180 °, and the molds 24 and 26 are returned to the original state, and the firing is performed.

In the mold clamping mechanism 30, the dies 24,
When the mold clamping of 26 is completed, the next mold 24, 2
6. Perform mold clamping. Here, for the sake of explanation, the dies 24 and 26 that have been previously clamped are referred to as a die F, and the following dies 24 and 26 are referred to as a die S. The next mold S clamped in the same manner as the previous mold F is received by the right mold turning mechanism 50 by the loading / unloading wheels 38 of the mold clamping mechanism 30 or the like. When the reception of the mold S is completed, the carriage 62 is moved to the right end, and the mold S is positioned at the position shown in FIG. When the carriage 62 is moved to the right end, the left mold turning mechanism 50 and the preceding mold F are positioned at the center of the blowing station B, and the carry-in / out wheels 52t of the left mold turning mechanism 50 are clamped. It becomes continuous with the loading / unloading wheel 38 of the mechanism 30.

In this state, the right blow head 42 descends, and molding sand is blown into the molding sand blowing port of the mold S positioned at the right end of the blowing station B. In addition,
The process from sand removal to firing is performed in the same manner as in the mold F described above. In this way, when the predetermined time has elapsed and the sintering of the molding sand in the former mold F is completed, the mold F is moved to the mold turning mechanism 50.
Is returned to the mold clamping mechanism 30 by the loading / unloading wheels 52t. In FIG. 3, the molds F at the blowing station B and the mold clamping station T are the same mold.

The mold F returned to the mold clamping mechanism 30 is fixed to the fixed vise 34 by the first clamp 34k.
And the movable mold 26 is connected to the movable vise 36 by the second clamp 36k. Further, the third clamp 26c is opened, and the clamp between the fixed mold 24 and the movable mold 26 is released. In this state, the mold is opened by moving the movable vise 36 in a direction away from the fixed vise 34. When the mold is opened, a reversing cylinder (not shown) is operated to rotate the fixed mold 24 and the fixed vise 34 by about 90 °, and the cavity surface of the fixed mold 24 is turned upward. The core product is taken out.
Thus, the opened mold F is clamped again, and is conveyed to the mold turning mechanism 50. Then, by repeating the above procedure, core products are alternately formed by the dies F and S.

As described above, according to the present embodiment, even in the operation using a plurality of dies, only one mold clamping mechanism is required, so that the equipment occupying area can be reduced and the equipment cost can be reduced. Is done.

[Brief description of the drawings]

FIG. 1 is a front view of a core molding apparatus according to a first embodiment of the present invention.

FIG. 2 is a side view of the core molding apparatus according to the first embodiment of the present invention.

FIG. 3 is a plan view of a core molding apparatus according to a second embodiment of the present invention.

FIG. 4 is a front view of a core molding apparatus according to a second embodiment of the present invention.

FIG. 5 is a side view of a core molding apparatus according to a second embodiment of the present invention.

FIG. 6 is a side view of a conventional core molding apparatus.

[Explanation of symbols]

 14 Lower mold 16 Upper mold 12 Elevating cylinder (mold clamping mechanism) 13 Mold fixing member (mold clamping mechanism) 15 Mold turning frame 15k Second clamp 15s Third clamp 18 Blow head 24 Fixed mold 26 Movable mold 26c Third clamp 30 Mold clamping mechanism

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenjiro Tsuji 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Hidenori Nagai 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation ( 72) Inventor Koji Sano 84 Kawasaki, Odaka-cho, Midori-ku, Nagoya-shi, Aichi Kenji Ohashi, Examiner of Toyo Industrial Machinery Co., Ltd. (56) References JP-A-6-339747 (JP, A) Japanese Utility Model No. 3-62649 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B22C 9/10 B22C 13/08

Claims (2)

(57) [Claims] 1. A core molding method for molding a sand core by filling molding cavities into a cavity of a mold from above a mold that has been clamped, wherein the mold is vertically moved by a mold clamping mechanism. Clamping the mold, clamping the clamped mold, removing the clamped mold from the mold clamping mechanism and rolling independently, so that the casting sand injection port of the mold faces upward. And a step of positioning a mold. 2. A core molding method for molding a sand core by filling molding cavities in a cavity of a clamped mold, wherein a step of clamping the clamped mold is performed. Removing the mold from the mold clamping mechanism, transporting the mold to another position, and filling with molding sand.