JP2825936B2 - Gate position changing mechanism in mold making machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a gate position changing mechanism for changing a gate position in a mold formed by a mold making machine, and particularly to easily changing a gate position. The present invention relates to a novel gate position changing mechanism that can be performed quickly and quickly.

2. Description of the Related Art Conventionally, as a type of a molding machine for molding a casting mold by compacting molding sand in a molding frame, a pair of molding plates are formed on both sides of a pattern plate on which a model is integrally formed. The frames (the upper frame and the lower frame) are overlapped, and a compression plate is fitted into the outer opening of each of the molding frames to cover the molding plates, thereby forming a predetermined molding space in the molding frames. 2. Description of the Related Art There is known an apparatus in which a casting mold filled in a space is compacted to obtain a target mold (upper mold and lower mold) having a casting cavity having a shape corresponding to the model.

In such a mold making machine, usually, a rod-shaped sprue bar extending toward the pattern plate side is provided upright with respect to one of the compression plates fitted into the outer opening of the flask. The molding operation as described above is performed in a state in which the sprue rod is brought into contact with the pattern plate, and thereafter, the sprue rod is pulled out of the mold, thereby communicating with the casting cavity formed in the mold. A gate for hot water is formed.

However, in such a sprue, the formation position is appropriately determined according to the size and shape of the casting cavity formed in the mold. (Model) Every time it was exchanged, it was necessary to remove the sprue bar from the compression plate and replace it at a different position. The problem is that the time loss is large and the molding cycle is reduced.

Therefore, conventionally, for example, it has been proposed that a sprue bar be erected at a position corresponding to each model with respect to a pattern plate. However, even when the sprue bar is provided on the pattern plate side in this way, the sprue cup part (hot water tray forming part) cannot be formed on the pattern plate side because the draft angle is reversed, and the sprue cup part is not provided. Only has to be formed for the compression plate,
Further, in this case, since the plurality of sprue cups must be formed at positions corresponding to the standing positions of the sprue bars in various pattern plates, a plurality of unnecessary spouts are required for the obtained mold. Cup part (hot water tray)
Is formed, and the unnecessary cavity causes a reduction in the thickness of the wall of the casting cavity, thereby causing a problem that the moldability of the mold is adversely affected.

In addition, piston-type sprue bars that can be contracted / projected by a piston mechanism are provided at a plurality of positions on the compression plate, respectively.
According to a model of a pattern plate to be used, there has been proposed a type in which an appropriate gate member is protruded and used. However, even with such a piston-type sprue rod, it is extremely difficult to completely store even the sprue cup portion in the compression plate due to its structure.
For this reason, it is inevitable that a plurality of unnecessary cup portions are formed in the obtained mold, and as in the case where the gate is provided on the pattern plate side as described above, adverse effects on the moldability of the mold are caused. Is a problem.

(Problem to be Solved) Here, the present invention has been made in view of the above-described circumstances, and the problem to be solved is that the change of the pouring gate position at the time of the change of the mold involves the molding of the mold. It is an object of the present invention to provide a gate position changing mechanism in a mold making machine which can be performed quickly and with excellent workability without adversely affecting the pouring gate.

(Solution) In order to solve the above problem, in the present invention, a pair of casting frames are overlapped on both sides of a pattern plate on which a model is integrally formed, and each of the casting frames is cast. By fitting a compression plate into the outer opening of the frame and covering it, a predetermined molding space is formed in those molding frames, and in the molding space, the filled molding sand is compacted. In a mold molding machine for molding a predetermined mold, for the one compression plate, a movable plate facing the pattern plate is provided rotatably on a surface of the compression plate facing the pattern plate,
Further, while providing a driving means for rotating the movable plate around the rotation center axis, the movable plate is protruded toward the pattern plate side, and is brought into contact with the pattern plate, thereby forming a gate in the mold. The feature of the present invention is a gate position changing mechanism in a mold making machine in which a gate to be formed is erected from the rotation center axis of the movable plate to be erected.

(Example) Hereinafter, in order to clarify the present invention more specifically, an example of the present invention will be described in detail with reference to the drawings.

First, FIG. 1 schematically shows a specific example of a mold making machine provided with a sprue bar having a structure according to the present invention. In this figure, reference numerals 10 and 12 denote an upper frame and a lower frame as cast frames, which are supported by a guide bar 14 so as to be movable in the approaching / separating directions. The upper frame 10 and the lower frame 12 are supported by a support 16 via a guide bar 14, and are moved together with the support 16 by a reversing cylinder 18 in the direction of the arrow in FIG.
Each time, it can be rotated integrally. Then, as indicated by virtual lines in the figure, the upper frame 10 and the lower frame 12
And a squeeze head 19 as a compression plate, which is located on both sides in the overlapping direction of the upper frame 10 and the lower frame 12 at the rotation position of the support base 16 to be superimposed in the horizontal direction. An upper squeezing device 20 and a lower squeezing device 22 are provided, respectively.
A blow device 32 is disposed above the lower frame 12 and the upper frame 10, while the upper frame 10 and the lower frame 12 are overlapped in the vertical direction as indicated by a solid line in the drawing. When the support 16 is to be rotated, the upper frame 10
A mold removing device 24 and a mold receiving device 26 are disposed on both sides in the direction of superposition of the lower frame 12 and the lower frame 12, respectively.

When the mold is formed by the mold forming machine having such a structure, first, at the turning position of the support base 16 as shown by a solid line in FIG.
As shown in the figure, a model 28 molded into a required casting shape is integrally formed at a central portion by a pattern transfer device (not shown) between opposing surfaces of the upper frame 10 and the lower frame 12. The pattern plate 30 is guided and positioned, and the upper frame 10 and the lower frame 12 are sandwiched by the pattern plate 30.
And are superimposed.

Thereafter, as shown in FIG.
Are pivoted to pivot positions as indicated by phantom lines in FIG. 1, and further, the upper squeezing device 20 and the lower squeezing device The 22 squeeze heads 19 are fitted and the openings are covered, so that predetermined molding spaces 34 are formed inside the upper frame 10 and the lower frame 12. Also, there, the squeeze head of the upper squeeze device 20
A sprue bar 35 is provided upright at 19, and the front end surface thereof is brought into contact with the pattern plate 30 in the molding space 34.

Then, under such a state, the molding spaces 34, 34 are formed through the feed holes 36, 36 provided in the upper frame 10 and the lower frame 12.
The casting sand 38 is fed and filled from the blow device 32 into the inside, and further, after the casting sand 38 is charged into the molding spaces 34, 34, both of the upper and lower squeezing devices 20, 22 are filled. The squeeze heads 19, 19 are displaced in a direction approaching each other with a predetermined pressure, and the molding sand 38 is compression-molded, so that an upper mold 40 and a lower mold 42 as molds are formed.
Each is molded (see FIG. 2 (c)).

Then, as shown in FIG. 2 (c), after forming the upper die 40 and the lower die 42, the upper and lower squeezing devices 20,
The squeeze heads 19 and 19 in 22 are released from the mold, and at the same time as the release of the compression plates 19 and 19, the sprue bar 35 is also punched out. A gate 43 having a shape corresponding to 35 is formed.

Further, after the squeeze heads 19, 19 are released from the mold, the support base 16 is turned to a turning position as shown by a solid line in FIG. 1, and is shown in FIG. 2 (d). Like
When the upper frame 10 and the lower frame 12 are separated from each other, the pattern plate 30 having the model 28 is removed from the upper mold 40 and the lower mold 42. It should be noted that, as is well known, the upper frame 10 and the lower frame
When the pattern plate 30 is protruded by a predetermined amount by a protrusion mechanism (not shown) provided in the mold 12, the pattern plate 30 is die-cut from the upper die 40 and the lower die 42 at the same time. .

Then, after removing the pattern plate 30 and further inserting the core as necessary, as shown in FIGS. 2 (e) and 2 (f), the upper frame 10 and the lower frame 12 are again joined. With the upper mold 40 and the lower mold 42 superimposed on each other in the mold removing device 24, the upper frame 10 and the lower frame 12 are die-cut onto the mold receiving device 26 from the upper frame 10 and the lower frame 12, thereby forming a predetermined shape. Thus, the intended frameless mold is obtained in which the casting cavity 44 and the gate 43 communicating with the casting cavity 44 are respectively formed inside.

By the way, the squeeze head 19 of the upper squeezing device 20 in the mold molding machine having such a structure is provided with a third
As shown in FIG. 4 and FIG. 4, a rotating plate 44 as a movable plate is disposed on the surface on the pattern plate 30 side, and the sprue bar 35 is attached to the rotating plate 44. Have been.

More specifically, the rotating plate 44 is formed in a disk shape, and integrally has a rotating shaft 46 protruding at a predetermined length on one side in the axial direction. The rotating shaft 46 is fitted in the squeeze head 19 and supported rotatably in a state where the rotating shaft 46 extends in the direction in which the squeeze head 19 and the pattern plate 30 are opposed to each other. On the surface (front surface) 58 of the squeeze head 19 on the side of the pattern plate 30, the squeeze head 19 is arranged so as to be rotatable around an axis in a plane parallel to the pattern plate.

Further, a piston member 48 is fitted and fixed to an axially intermediate portion of the rotating shaft 46 of the rotating plate 44, while rotating shaft support members 50, 52,
A cylinder chamber 56 is formed by 54, and the rotation of the rotating shaft 46 in the axial direction is performed by supplying and discharging compressed air into the cylinder chamber 56 based on the switching operation of the air valve 59 by the piston member 48 and the cylinder chamber 56. An air piston mechanism is configured to be displaced by a predetermined dimension.

That is, based on the operation of the air piston mechanism, the rotating plate 44 is moved to the front surface 58 of the squeeze head 19.
In this state, the rotating plate 44 is in close contact with the front face 58 of the squeeze head 19 with the annular seal rubber 60 interposed therebetween. In addition to preventing the intrusion of molding sand and the like into the gap, the rotation resistance of the rotation plate 44 can be exerted, while the rotation of the rotation plate 44 causes a small sliding resistance under the separated state. It can be tolerated.

The sprue bar 35 is screwed onto the rotating plate 44 mounted on the squeeze head 19 in this manner, so that the pattern plate 30 is shifted from the rotation center of the rotating plate 44 by a predetermined dimension. It is erected so that it protrudes to the side. Thereby, the position of the gate 35 protruding above the squeeze head 19 can be moved on one circumference (A) around the rotation center of the rotary plate 44 based on the rotation of the rotary plate 44. It is.

Further, a gear 62 is non-rotatably mounted on a protruding end of the rotating shaft 46 of the rotating plate 44. A pinion 68 mounted on a drive shaft 66 of a motor 64 as driving means is meshed with the gear 62, and the rotational driving force of the motor 64 is transmitted to the rotating plate via gear means.
It is to be affected by the rotation axis 46 of 44,
Thus, based on the rotation operation of the motor 64, the rotation position of the rotation plate 44 can be appropriately changed. In FIG. 3, 70 is a drive shaft of the motor 64.
It is a protective sleeve that covers 66. An expansion joint mechanism is provided at an intermediate portion in the axial direction of the drive shaft 66 and the protective sleeve 70 as necessary, so that the position at which the motor 64 is fixed is thereby fixed. The displacement of the squeeze head 19 during molding can be allowed.

Furthermore, a pinion 72 is mounted on the base side of the drive shaft 66 of the motor 64, and a gear 76 having a detection plate 74 is meshed with the pinion 72, so that the motor 64 The drive shaft 66 is rotated in accordance with the rotation operation. Then, a switch mechanism that can be caused to run on the outer peripheral surface of the detection plate 74
At 78, by detecting a signal set on the detection plate 74, the rotation position of the drive shaft 66 of the motor 64, and thus the rotation plate 44, is detected, and the rotation position can be controlled. It has become.

Therefore, in the mold making machine including the gate position changing mechanism structured as described above, even when the change of the gate position is required at the time of changing the mold, the switch mechanism 78 is operated to operate the motor 64. By rotating by a predetermined amount, the standing position of the sprue bar 35 in the squeeze head 19 can be appropriately changed, and since it is not necessary to remove or replace the sprue bar 35 individually, the position of forming the sprue bar 35 Can be made quickly and with good workability, and an improvement in the molding cycle can be advantageously achieved.

Further, in such a sprue position changing mechanism, since the standing position of a single sprue bar 35 is changed, a plurality of unnecessary cup portions (a hot water receiving pan) ) Is not formed, or the moldability of the mold is not inhibited by such a cup portion.

Furthermore, in the present embodiment, the rotating plate 44 is
Since the air plate mechanism is provided for displacing the front surface 58 of the squeeze head 19 by a predetermined dimension in the contact / separation direction, the rotation plate 44 is separated from the squeeze head 19 to change the rotation plate 44 when the gate position is changed. The driving force for rotating the squeeze head 19 can be reduced, and by bringing the rotating plate 44 into contact with the squeeze head 19, it is possible to effectively prevent casting sand from entering the rotating part during molding. -ing

Furthermore, the rotating plate is provided by the piston mechanism.
44 is brought into contact with the front surface 58 of the squeeze head 19, whereby the rotation of the rotating plate is prevented, and
Can advantageously be made.

Next, FIG. 5 shows another embodiment of a mold making machine having a gate position changing mechanism structured according to the present invention. In the present embodiment, the same reference numerals are given to members having the same structure as the first embodiment, and the detailed description thereof will be omitted.

That is, in the present embodiment, the squeeze head 19 in the upper squeeze device is formed with a hollow structure having a hollow cavity 80 therein. A circular arrangement hole 82 is provided on the surface of the squeeze head 19 on the side facing the pattern plate, and is fitted into the arrangement hole 82 to cover the arrangement hole 82. In addition, a disk-shaped rotating plate 44 on which the sprue bar 35 is fixed upright is provided.

Further, the rotating plate 44 is rotatable around the central axis in the disposing hole 82, and the rotating shaft 46 is rotated by the rotation driving means 84 as in the first embodiment. Thereby, it is guided to a predetermined rotation position.

Further, the squeeze head 19 is provided with an air supply hole 86 penetrating the wall thereof.
The compressed air is supplied into the hollow cavity 80 through the hole. As a result, the compressed air supplied into the hollow cavity 80 is discharged to the outside through the space between the arrangement hole 82 formed in the squeeze head 19 and the sliding surface of the rotating plate 44. .

Therefore, even in the mold making machine including the gate position changing mechanism having such a structure, the standing position of the gate bar 35 in the squeeze head 19 can be appropriately changed by rotating the rotating plate 44. As in the first embodiment, the position at which the gate is formed can be changed quickly and with good workability, and an improvement in the molding cycle can be advantageously achieved.

In addition, in this embodiment, a part of the wall of the squeeze head 19 is formed by the rotating plate 44, and the rotation plate 44 is prevented from protruding from the front surface 58 of the squeeze head 19. Therefore, no recess is formed by the rotating plate 44 in the mold to be formed.

Furthermore, in this embodiment, since the compressed air can be discharged through the space between the arrangement hole 82 formed in the squeeze head 19 and the sliding surface of the rotating plate 44, such sliding Due to the air layer formed between the surfaces, the rotational resistance of the rotating plate 44 can be advantageously reduced, and the intrusion of molding sand or the like between the sliding surfaces can be effectively prevented and the surface can be cleaned. It is doing.

Although the embodiments of the present invention have been described in detail above, these are literal examples, and the present invention is not construed as being limited to such specific examples.

For example, in the above-described embodiment, the motor 64 is used as a driving unit that exerts a rotational driving force on the rotating plate 44. However, various other known driving units such as a piston mechanism can be employed. .

In order to more accurately control the operation of such a driving unit, a servomotor may be used as the driving unit, or a limit switch or the like may be used.

Furthermore, in the above-described embodiment, the movable range of the sprue bar 35 is set to be one circle around the rotation center of the rotating plate 44, but the standing position of the sprue bar 35 on the rotating plate 44 is By changing the direction, the movable range can be easily expanded.

Further, in the above-described embodiment, the rotating plate 44 allowed to rotate on one axis is used as the movable plate. However, the moving form of the movable plate is not limited to this, and is parallel to the other pattern plates. It is also possible to use a movable plate that allows various forms of movement within a plane, for example, rotation having a rotation axis and a revolution axis, or reciprocation (slide movement) in a linear direction without rotation. It is.

In addition, the mold making machine to which the present invention is applied is not to be construed as being limited by the above-described embodiment, and is limited to various mold making machines, particularly to a frameless mold making machine. Of course, none of them can be applied to advantage.

In addition, although not enumerated one by one, the present invention can be embodied in modes in which various changes, modifications, improvements, etc. are added based on the knowledge of those skilled in the art. Needless to say, all of them are included in the scope of the present invention unless departing from the gist of the present invention.

(Effects of the Invention) As is clear from the above description, in the gate position changing mechanism in the mold making machine configured according to the present invention, by operating the driving means to move the movable plate by a predetermined amount, Since the standing position of the sprue bar on the compression plate can be changed, even when changing the sprue forming position when changing the mold, there is no need to remove or replace the sprue bar one by one. The formation position can be changed quickly and with good workability, so that an improvement in the molding cycle can be advantageously achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing a specific example of a mold making machine provided with a gate position changing mechanism structured according to the present invention. FIGS. 2 (a) to 2 (f) are process explanatory diagrams for explaining a mold making process in the mold making machine shown in FIG. FIG. 3 is an enlarged sectional view of a main part showing a gate position changing mechanism in the mold making machine shown in FIG. 1, and FIG. 4 is a left side view in FIG. FIG. 5 is a cross-sectional view of a main part schematically showing another specific example of the gate position changing mechanism structured according to the present invention. 10: Upper frame, 12: Lower frame 19: Squeeze head, 20: Upper squeeze device 22: Lower squeeze device, 28: Model 30: Pattern plate, 34: Molding space 35: Sluice bar, 38: Foundry sand 40: Upper mold , 42: Lower mold 44: Rotating plate, 46: Rotating shaft 64: Motor, 66: Drive shaft 80: Hollow cavity, 82: Arrangement hole 84: Rotation driving means, 86: Air supply hole

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B22C 23/00

Claims (3)

(57) [Claims] 1. A pair of flasks are superimposed on both sides of a pattern plate in which a model is integrally formed, and a compression plate is fitted into the outer opening of each of the flasks to cover them. Thus, a predetermined molding space is formed in the molding flask, and in the molding space, the filled molding sand is compacted to form a predetermined mold. On the other hand, a movable plate facing the pattern plate is rotatably provided on a surface of the compressor facing the pattern plate, and drive means for rotating the movable plate around a rotation center axis is provided. ,
With respect to such a movable plate, a sprue bar which forms a gate in the mold by projecting toward the pattern plate side and being brought into contact with the pattern plate is erected from the rotation center axis of the movable plate. A gate position changing mechanism in a mold making machine, characterized in that: 2. A gate position changing mechanism in a mold making machine according to claim 1, further comprising an air piston mechanism for displacing said movable plate in a contact / separation direction with respect to said compression plate. 3. A circular arrangement hole is provided on a surface of the compression plate facing the pattern plate, and the movable plate is arranged to fit into the arrangement hole and cover the arrangement hole. The compressed air is discharged to the outside through the holes and the sliding surface of the movable plate.
3. The gate position changing mechanism in the mold making machine according to item 2 or 2.