JPH11207435A - Mold positioning mechanism - Google Patents

Abstract

(57) [Problem] To provide a mold positioning mechanism capable of restricting expansion of a mold in one direction and suitably eliminating generation of a gap in a division surface of a split mold in the expansion direction. . A split mold (60a) corresponding to a plan section and a split mold (60c) corresponding to a product section are provided.
a, 60c and the movable mold mounting plate 52 are provided with a plurality of key members and key grooves which are fitted to each other, and
0c has a key member 76s and a key groove 7 at at least one place.
8s, the divided molds 60a and 60c each have a key portion that fits with a gap in one direction, and the movable mold is attached to the divided mold 60a. Pressing means is provided for pressing the split mold 60a in one direction against the split mold 60c by the elastic force of the coil spring 94 via the bracket 84 fixed to the plate 52.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold positioning mechanism, and more particularly, to eliminating a gap formed on a divided surface or the like when a divided mold is attached to a mold mounting plate to obtain a cast product. In addition, the present invention relates to a mold positioning mechanism capable of preventing occurrence of casting burrs and the like.

[0002]

2. Description of the Related Art Conventionally, when a mold is mounted on a mold mounting plate, as shown in Japanese Utility Model Laid-Open No. 1-114136,
Insert a round pin or square pin protruding from the joint surface of the mold
The mold is positioned on the mold mounting plate by closely fitting a round hole or a square hole formed on the joining surface of the mold.

[0003] However, for example, in order to improve the efficiency of the repair and replacement work of the mold, when the mold is divided into a severely worn portion and a durable portion, particularly when the mold is divided. If the mold mounting plate is made of a different material, a shear force acts on the pin due to the difference in thermal expansion between the mold mounting plate and the mold, and the pin or the hole for pin fitting is locally deformed. As a result, the amount of deviation of each mold changes, and a gap is generated in the divided surface, and when molten metal enters the gap, there is a disadvantage that a casting burr is generated.

[0004] In order to overcome this inconvenience, the present applicant has proposed an invention "a mold positioning mechanism" in Japanese Patent Application No. 6-310905. According to the present invention, a plurality of key members and a key groove are provided on a joint surface between the mold mounting plate and the mold, and the key members are fitted to the key grooves by defining a gap in one direction. On the other hand, the key member of the reference key portion and the key groove are fitted without any gap.
Therefore, the direction of elongation due to thermal expansion of the mold can be restricted in one direction around the reference key portion. On this occasion,
As a direction in which elongation is allowed, for example, a direction in which no gap is formed in the divided surface that divides the molten metal passage can prevent the generation of casting burrs on the divided surface. In addition, since there is a gap in one direction except for the reference key portion, no excessive force acts on the pin or the like, and no deformation or the like occurs. Further, by providing the reference key portion in the split mold on the product portion side, the product portion of the fixed mold and the movable mold is less likely to be displaced from each other, and it is possible to suppress the occurrence of casting burrs and the like in the product. The effect is obtained.

[0005] In the above-mentioned prior art, when a plurality of split molds are to be joined at a specific portion, an extremely long bolt is sometimes used. This is shown in FIG.
Shown in In FIG. 6, reference numeral 2 denotes a mold mounting plate, on which a first split mold 4 and a second split mold 6 are fixed. As can be easily understood from FIG. 6, two bolts 8a and 8b are screwed into the first split mold 4 from the mold mounting plate 2, and the first split mold 4 is attached to the mold. It is fixed to the plate 2. On the other hand, a key groove 10 is formed between the second split mold 6 and the mold mounting plate 2, and a key member 12 is fitted in the key groove 10 and the key member 1
2, the bolt 14 is screwed into the mold mounting plate 2, whereby the mold mounting plate 2 and the second split mold 6 are integrated. The first split mold 4 has through holes 16a, 1
6b are bored in parallel, and long bolts 18a, 18b are inserted into the through holes 16a, 16b, and the ends thereof are screwed into the screw holes 19a, 19b of the second split mold 6, respectively. Therefore, the first split mold 4 and the second split mold 6 are integrated by the long bolts 18a and 18b.

By the way, in this kind of integral structure of the split mold, the cycle of pouring, cooling, and taking out the product is repeated, so that the split mold itself expands and contracts. As a result, the first mold is caused. A gap is formed between the split mold 4 and the second split mold 6, and if left unchecked, this may cause the formation of casting burrs. Therefore, there is a disadvantage that the long bolts 18a and 18b must be frequently tightened.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a mold positioning mechanism for restricting the expansion of a mold in one direction, in which the occurrence of a gap in the division surface of the split mold in the direction of expansion is preferably eliminated. It is an object of the present invention to provide a mold positioning mechanism which can perform the above-mentioned operation and does not need to retighten a long bolt.

[0008]

In order to solve the above-mentioned problems, the present invention has at least a first split mold corresponding to a plan section and a second split mold corresponding to a product section. A plurality of key members and key grooves which are fitted to each other on a joint surface between the first and second split molds and the mold mounting plate, and at least one portion is provided in the second split mold. In the mold positioning mechanism having a reference key portion, the first and second split molds have a key portion fitted with a gap in one direction, and the first split mold has an elastic member. And pressing means for pressing the first split mold in one direction with respect to the second split mold via the.

In this case, it is preferable that the pressing means includes at least a bracket and a coil spring held by the bracket, but the pressing means is not limited to this. Further, the pressing means is provided with a first and a second.
It is preferable to provide the die mounting plate for holding the divided die.

Thus, in the positioning mechanism for restricting the expansion of the mold in one direction, the positioning mechanism generated on the other allowable one-way mold dividing surface by a simple method using the elastic force of the elastic member. It is possible to suitably prevent casting burrs from being generated due to the gap, and perform positioning with high accuracy.

Further, since the reference key portion is provided on the product portion side, the product portion of one mold and the product portion of the other mold are less likely to be displaced from each other, and the occurrence of casting burrs and the like is suppressed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

The mold positioning mechanism according to the present invention is applied, for example, to a casting mold of a system for automatically casting a crankshaft, which is a component of an engine, as shown in FIG.

In the casting system, a casting device 20 is disposed at substantially the center of the casting system. The casting device 20 includes a fixed mold 22 and a movable mold 24. A fixed mold is provided upstream of the casting device 20. A pouring station 26 for pouring the molten metal into a product cavity formed when the movable mold 24 and the movable mold 24 are closed is provided.

The pouring station 26 is a pressurized pouring furnace 2
8, a load cell 30, and a ladle 32 for receiving the molten metal discharged from the pressure pouring furnace 28 and pouring the molten metal into the casting apparatus 20. The load cell 30 reduces the amount of molten metal in the ladle 32 to a constant amount. After setting, the ladle 32
Is moved onto the casting apparatus 20 and poured into the product cavity from the gate.

Further, the molten metal generated in the melting furnace 34 disposed further upstream is supplied to the pressure pouring furnace 28 through a transfer ladle 36. Further, an additive measuring device 38 for adding an additive such as magnesium for spheroidizing graphite to the molten metal is provided above the casting device 20.
Further, a blow smoke device 40 for applying a release material to the cavity surface is provided adjacent to the additive measuring device 38 so as to be vertically movable.

A work take-out robot 42 for taking out a casting from the opened mold is horizontally movably provided above the casting apparatus 20 on the downstream side. Transfer.

Then, after performing trimming and the like by the straightening / cutting device 44, the material is transferred to a heat treatment furnace 48 by a transfer robot 46.

The fixed mold 22 and the movable mold 2 of the casting apparatus 20
4 includes a mold 58 and a mold 60 that are clamped and held on a fixed mold mounting plate 50 and a movable mold mounting plate 52 via respective clamp mechanisms 54 and 56, and the movable mold mounting plate 52 includes The mold clamping cylinder unit 64 attached to the fixed frame 62 is connected. In the present embodiment, the fixed mold mounting plate 50 and the movable mold mounting plate 52 are made of cast iron or steel, and the dies 58 and 60 are made of a copper alloy having good heat conductivity. Then, the fixed mold 22 and the movable mold 2
When the mold 4 is clamped, a cavity is formed on the mold mating surface of each of the molds 22 and 24.

This cavity is used for the mold 60 of the movable mold 24.
Will be described as an example. As shown in FIG.
Consists of a plan part 66 provided in the center and a pair of product parts 68, 68 provided on both sides.
The vertical runner 72 is connected to the gate 70, and the horizontal runners 74, 74 are separated from the bottom of the vertical runner 72 to the left and right. In FIG. 3, reference numerals 75 and 77 indicate push pins.

The dies 58 and 60 of the fixed die 22 and the movable die 24 according to the present embodiment are divided into a part corresponding to the plan part 66 and a part corresponding to the product parts 68. However, the details will be described using the movable mold 24 shown in FIG. 2 as an example.

As shown in FIG. 2, the mold 6 of the movable mold 24
0 denotes a first split mold 60a in which the central and lower plan portions 66 are formed, and a second and third split molds 60b, 60c in which the left and right product portions 68, 68 are formed by a split surface q. , R
The first to third split molds 60a to 60c are all made of the same material of copper alloy.
As described above, since each of the divided molds 60a to 60c is divided into three parts, the product parts 68, 6 are repaired or replaced.
In comparison with No. 8, the thermal depletion is severe and the molten metal temperature is high.
Only repairs and replacements are required, which is economical.

In this case, the movable mold mounting plate 52 and the mold 60
A plurality of square key members 76 and key grooves 78
Are provided and are fitted to each other (see FIG. 3). Then, for example, a steel key member 76 is fixedly protruded from the movable mold mounting plate 52 side via a bolt 80, and
The corresponding key groove 78 is provided on the side, but of course, these positions may be reversed.

Further, the key members 76 near the communicating hot water passages 82, 82 where the molten metal passages are divided by the dividing surfaces q, r.
s, 76s and the key grooves 78s, 78s are configured as a reference key portion S, and are fitted in the upper, lower, left, and right directions in a tight manner.
A gap is set only in the middle and left directions. These reference key portions S are provided on the second and third split molds 60b and 60c on the product portion 68 side (see FIG. 2). In addition, the other key members 76 and key grooves 78 are all provided with gaps in the vertical direction and the depth direction, and only the depth direction orthogonal to the paper surface in FIG.

In the present embodiment, the second and third split molds 60b and 60c and the first split mold 60a are used.
The following configuration is adopted when integrating the above.

That is, as shown in FIG. 5, the bracket 84 is fixed to the movable mold mounting plate 52. The bracket 84 is formed in advance with a hole 88 through which a head of a bolt 86 described later penetrates. A seating member 90 is provided on the upper surface of the bracket 84, and a bolt 86 is screwed from the seating member 90 into the first split mold 60a by using a hole 88. In this case, a concave portion 92 is formed in the first split mold 60a, and the bolt 86 surrounds a coil spring 94 having extremely high elastic force between one surface 92a of the concave portion 92 and one surface of the seating member 90. To be interposed. Therefore, the first split mold 60
5a is urged upward in FIG. 5 by the elastic force of the coil spring 94, and constantly presses the third split mold 60c upward.

The second split mold 60b has the same structure as that described above, and is connected to the second split mold 60b via the first split mold 60a in FIG.
It is pressed upward.

Next, the operation of the casting mold configured as described above will be described. Mold clamping cylinder unit 64
Thus, the fixed mold 22 and the movable mold 24 are clamped, and the molten metal is poured from the gate 70 to fill the product part 68 and the plan part 66 with the molten metal. As a result, the fixed mold 22, the movable mold 24
And the fixed mold mounting plate 50 and the movable mold mounting plate 52 expand due to the heat of the molten metal. However, since the copper-based material usually has a higher coefficient of thermal expansion than the iron-based material, the fixed mold mounting plate 50 The extension of the fixed mold 22 and the movable mold 24 is larger than that of the movable mold mounting plate 52. In this case, the key member 7 of the reference key portion S
6 s and the key groove 78 s are fitted in the up, down, left, and right close contact, so that the position deviation near the reference key portion S hardly occurs,
Elongation occurs around the position of the reference key portion S.

That is, the other key member 76 and the key groove 78 are in close contact with each other in the left-right direction, and a gap is formed only in the up-down direction. Therefore, the extending direction of the fixed mold 22 and the movable mold 24 is almost only in the up-down direction. With reference to the reference key portion S, a portion above the reference key portion S extends only upward, and a portion below the reference key portion S extends only downward. Accordingly, there is almost no displacement in the vicinity of the continuous hot water passages 82, 82 that divide the molten metal passage, and since the direction of elongation is parallel to the direction of the continuous hot water passage 82, no lateral displacement of the molten metal passage occurs.
The occurrence of casting burrs on the divided surfaces q, r near the communicating hot water paths 82, 82 is suppressed.

Since the reference key portion S is provided in the second and third split molds 60b and 60c on the product portion 68 side,
It is difficult for the displacement between the fixed mold 22 and the product part 68 of the movable mold 24 to occur, and it is possible to suppress the occurrence of casting burrs and the like between the fixed mold 22 and the movable mold 24. Then, when the surface layer of the molten metal in the cavity solidifies into a shell, the mold opens,
The product is extruded by the extrusion pins 75 and 77.

In the present embodiment, the resilient force of the coil spring 94 is applied to the first split mold 60a via the seating member 90 held by the bracket 84. For this reason, the first split mold 60a is always replaced with the second split mold 60b and the third split mold 60c in FIG.
Press upwards in the middle. Therefore, the first split mold 60a
Since there is no gap between the second and third split molds 60b and 60c, it is possible to suppress the occurrence of casting burrs.

That is, in the present embodiment, unlike the prior art shown in FIG. 6, long bolts 18a and 18b for integrating the first divided mold 4 and the second divided mold 6 are integrated.
Is not used. Instead, the first split mold 60a
Is constantly pressed by the resilience of the coil spring 94 to forcibly contact the second and third split molds 60b and 60c. Therefore, even if expansion and contraction occur in the first to third split molds 60a to 60c due to the pouring and cooling of the molten metal, the first split mold 60a and the second and third split molds 60b. ,
Since there is no gap between the first and second members 60c and 60c, there is an advantage that no casting flash is generated and that there is an advantage that complicated work such as re-tightening of bolts is released.

[0033]

As described above, in the mold positioning mechanism according to the present invention, the divided molds fixed to the mold mounting plate are forcibly connected to each other via a strong elastic member, preferably a coil spring. It is configured to be in close contact and integrated. Therefore,
Since there is no gap between the split molds and no displacement occurs, the formation of casting burrs can be prevented, and a cast product having good quality and requiring no operation such as removal of casting burrs can be obtained. Further, since there is no need to use a bolt for integrating the divided molds, there is no need for an operation such as retightening the bolt.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an entire casting system to which a mold positioning mechanism according to the present invention is applied.

FIG. 2 is a front view of a movable mold included in the casting apparatus shown in FIG.

FIG. 3 is a schematic side vertical sectional view taken along the line III-III of the movable mold shown in FIG. 2;

FIG. 4 is an enlarged view of a key member and a key groove shown in FIG. 2;

5 is a partially omitted longitudinal sectional view of the bracket, the coil spring, and the first and second split molds shown in FIG. 3;

FIG. 6 is an enlarged vertical sectional view showing an integrated structure of a mold mounting plate and a split mold according to the related art.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 20 ... Casting die 22 ... Fixed die 24 ... Movable die 50 ... Fixed die mounting plate 52 ... Movable die mounting plate 58, 60 ... Dies 60a-60c ... Split die 66 ... Mold part 68 ... Product part 70 ... Gate 72 ... Vertical runway 74 ... Horizontal runway 75,77 ... Extrusion pin 76,76s ... Key member 78,78s ... Key groove 80,86 ... Bolt 82 ... Communication runway 84 ... Bracket 90 ... Seat member 94 ... coil spring

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Masaaki Kurosawa 1-10-1 Shinsayama, Sayama City, Saitama Prefecture Honda Engineering Co., Ltd.

Claims (3)

[Claims] A first split mold corresponding to at least a plan part and a second split mold corresponding to a product part, wherein the first and second split molds, a mold mounting plate, A plurality of key members and a key groove which are fitted to each other on the joining surface of the mold, and wherein the second split mold has a reference key portion at at least one position. The second split mold has a key portion that fits with a gap in one direction, and the first split mold has a first split with respect to the second split mold via an elastic member. A mold positioning mechanism comprising a pressing means for pressing the mold in one direction. 2. A positioning mechanism according to claim 1, wherein said pressing means is provided on a mold mounting plate for holding said first and second split dies. 3. The positioning mechanism according to claim 1, wherein said pressing means includes at least a bracket and a coil spring held by said bracket.