JP6727914B2 - Hot chamber casting equipment - Google Patents

Description

The present invention relates to a hot chamber casting apparatus for manufacturing die cast products such as aluminum.

As a casting method for die-cast products manufactured using aluminum alloy as a material, there are a hot chamber method in which injection is performed in a relatively high temperature molten metal (molten metal material), and a cold chamber in which injection is performed while supplying the molten metal into the sleeve. The methods are roughly classified. Among these, the hot chamber method has the advantage that it is possible to cast, for example, pure aluminum having a relatively high melting point, and has a wide selection range of cast metal materials.

As a conventional hot chamber type aluminum die casting apparatus, for example, a vertical injection chamber is generally used as shown in FIG. 10 (see, for example, Patent Documents 1 and 2). This type of vertical chamber has a structure in which the metal material stored in the pod 93 is pressurized and supplied to the mold 95 via the branch cylinder 94 by the plunger 92 sliding up and down in the main cylinder 91. ..

JP, 2010-058131, A JP, 2011-110566, A

However, the conventional vertical chamber has a structure in which the plunger 92 is pressed vertically to inject a metal material, and a portion where a runner called a gooseneck bends between the main cylinder and the branch cylinder at an acute angle ( A relatively high injection pressure is required, for example, because of the presence of the runway 96) shown in FIG. Therefore, structurally, the mechanical load on the chamber is large, and there are problems in durability and device life. Further, there is a possibility that oxides floating on the surface of the molten aluminum adhere to the sliding parts of the main cylinder and the plunger, which also causes contamination of the injection metal material and damage to the chamber device.

The present invention has been made in view of such conventional problems, and by providing a casting apparatus having a more durable and longer life than the conventional one by simplifying the structure of the chamber. Has an aim.

In order to solve the above-mentioned problems, the hot chamber casting apparatus of the present invention is provided with a pod for storing a molten metal which is a molten metal material, and a molten metal channel for injecting the molten metal stored in the pod into a mold. a plunger nozzle base end side of the plunger nozzle is inserted into the chamber chamber, by reciprocating in a state where at least the entire said chamber chamber is immersed in the molten metal, and introducing the molten metal into the chamber chamber and said A movable cylinder for injecting into a mold through a molten metal channel, a drive device for outputting a pressing force for reciprocating the movable cylinder, and a connecting member for connecting the drive device and the movable cylinder, the drive device And a connecting member for transmitting the pressing force output by the movable cylinder to the movable cylinder , wherein the connecting member is in point contact with the movable cylinder to apply the pressing force to the movable cylinder. It is a device.

In the above-mentioned configuration, in the hot chamber casting device, it is preferable that the flow line of the movable cylinder and the direction of the central axis of the plunger nozzle are coincident with each other, and the point of action of the pressing force exists on the line of the central axis. ..

Further, in the hot chamber casting apparatus, the connecting member has a cylindrical portion, and a projection portion having a curved surface with a semi-circular cross section that extends annularly along the outer peripheral direction of the cylindrical portion is formed. It is preferable that the apex of the protrusion is in point contact with the movable cylinder.

Further, in the hot chamber casting apparatus, it is preferable that the columnar portion of the connecting member is fitted into the slot of the movable cylinder. Particularly, it is preferable that a groove hole is formed in a direction orthogonal to the flow line direction of the movable cylinder, and the cylindrical portion of the connecting member is inserted into the groove hole of the movable cylinder.

Further, in the hot chamber casting apparatus, it is preferable that a gap be formed between the groove hole of the movable cylinder and the cylindrical portion of the connecting member.

Further, the hot chamber casting apparatus is installed with the center axis of the chamber forming a predetermined angle with respect to the horizontal, and with the plunger nozzle side facing upward, the movable cylinder is immersed in the molten metal stored in the pod. Has been preferred. Particularly, it is preferable that the predetermined angle is within the range of 10 to 40 with respect to the horizontal.

According to the hot chamber casting apparatus of the present invention, its main structure can be simplified, and durability can be improved and life can be extended. In particular, since the connecting member is configured to make point contact with the movable cylinder and exert a pressing force, it is possible to effectively prevent the occurrence of damage or galling of the movable portion which may occur due to dimensional error or the like.

1 is a side view of a hot chamber casting apparatus according to an embodiment of the present invention. It is sectional drawing which illustrates the chamber structure of a hot chamber casting apparatus. It is a figure for demonstrating the structure of a nozzle tip part and a mold cross section. It is a side view for explaining the structure of a connecting member and a joint arm. It is a top view for explaining the structure of a drive, and its operation. It is a figure for demonstrating operation|movement of a hot chamber casting apparatus. It is a figure for further explaining operation of a hot chamber casting device. It is a figure for further explaining operation of a hot chamber casting device. It is a figure for further explaining operation of a hot chamber casting device. It is a figure for demonstrating the structure of the vertical chamber by a prior art.

Hereinafter, preferred embodiments of a hot chamber casting apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a configuration of a hot chamber casting apparatus 10 according to an embodiment of the present invention. FIG. 2 is a sectional view showing a chamber structure which is a main part of the hot chamber casting apparatus 10 shown in FIG.

The hot chamber casting apparatus 10 manufactures a cast product having a desired shape by pressurizing and injecting a molten metal material (hereinafter, referred to as “molten metal”) stored in the pod 60 into a cavity 73 which is a space in a mold. It is a device that does. The pod 60 is a tank capable of heating and holding the molten metal W at a constant temperature of 700° C. or higher, for example. Further, the pod 60 is appropriately replenished with a high temperature molten metal from a known melting furnace to keep the molten metal level constant.

Examples of metal materials of cast products manufactured by the hot chamber casting apparatus 10 include aluminum, aluminum alloys (for example, Al-Si system, Al-Si-Cu system), copper alloys, magnesium alloys, zinc alloys, and the like. In particular, the hot chamber casting apparatus 10 according to the present embodiment can prevent impurities from being mixed in and can be injection-molded at a high temperature and a low pressure. Therefore, for example, a precision component made of pure aluminum having high thermal conductivity is used. Suitable for casting.

The hot chamber casting apparatus 10 includes a plunger nozzle 20 that injects the molten metal W into a mold (fixed mold 71, movable mold 72), and a movable cylinder 30 that is reciprocated by a drive device 40. The mold is formed by a fixed mold 71 and a movable mold 72 abutting against each other.

The plunger nozzle 20 is made of heat-resistant ceramic and has a substantially columnar shape that extends straight. The plunger nozzle 20 is formed with a molten metal passage 21 penetrating the longitudinal center of the plunger nozzle 20.

In the present embodiment, since the plunger nozzle 20 is relatively movably inserted into the chamber chamber 31 of the movable cylinder 30, the “center axis” penetrating the center of the plunger nozzle 20 is the center of the chamber chamber 31. It coincides with the axis passing through. Furthermore, this central axis also coincides with the flow line of the reciprocating movable cylinder 30. That is, the “center axis of the chamber” means this axis passing through the centers of the plunger nozzle 20 and the movable cylinder 30.

A flange 22 is integrally formed on the tip end side of the plunger nozzle 20, and a fixed mold 71 is attached to the flange 22. It is preferable that the fixed mold 71 is detachably/removably attached to the flange 22 by, for example, bolts 74 and 74 so as to be compatible with die-cast products having various shape and dimension specifications.

Further, the nozzle tip portion 23 of the plunger nozzle 20 has a spherical shape, and is in pressure contact with the concave surface portion 71 a inside the fixed mold 71. The molten metal injected from the plunger nozzle 20 is injected into the cavity 73 through the injection path 71b (see FIG. 3). On the other hand, a part of the plunger nozzle 20 on the base end side is inserted into a chamber chamber 31 formed in the movable cylinder 30.

The movable cylinder 30 is also made of heat resistant ceramic. As shown in FIG. 2, the chamber chamber 31 of the movable cylinder 30 has a circular and straight depth with a diameter slightly larger than the diameter of the plunger nozzle 20 so that the plunger nozzle 20 can be relatively retractably inserted. It is formed as a hole. Further, molten metal holes 32, 32 that communicate the chamber chamber 31 with the outside are formed in a direction orthogonal to the central axis of the chamber chamber 31.

Further, the movable cylinder 30 is formed with a slot 35 in a direction orthogonal to the central axis in the longitudinal direction (that is, the flow line direction). The slot 35 has a square opening and penetrates the movable cylinder 30.

The chamber provided with the plunger nozzle 20 and the movable cylinder 30 is installed diagonally with the side of the plunger nozzle 20 connected to the mold facing upward and the movable cylinder 30 being immersed in the molten metal W. As described above, it is preferable that the center axis of the chamber forms a predetermined angle with respect to the horizontal, and the predetermined angle is within the range of 10 to 40°. As a result, metal oxides or the like floating on the surface of the molten metal W during the casting operation are not introduced into the chamber 31, and it is possible to prevent impurities from mixing into the molten metal material. Moreover, by arranging the center axis of the chamber obliquely, the injection pressure can be made smaller than that of the conventional vertical chamber. As a result, the mechanical load on the chambers 20 and 30 is reduced, and the life of the device can be improved. It also enables the casting of relatively thin precision parts.

The plunger nozzle 20 is provided with its position fixed. By moving (retracting) the movable cylinder 30 in a direction in which it is relatively separated from the plunger nozzle 20, the molten metal is introduced into the chamber 31. On the other hand, when the movable cylinder 30 moves (forwards) in a direction approaching the plunger nozzle 20, the molten metal in the chamber 31 is injected into the mold through the molten metal passage 21 of the plunger nozzle 20.

A heater 27 is preferably provided near the flange 22 of the plunger nozzle 20. The heater 27 heats a part of the plunger nozzle 20 arranged above the level of the molten metal W in the pod 60, so that the molten state of the metal material flowing through the nozzle portion near the mold can be maintained. Further, it is possible to improve the removal of the metal material remaining in the melt passage 21 after casting.

The connecting member 51 made of heat-resistant ceramic is a member that is connected to the drive device 40 and transmits a pressing force for reciprocating the movable cylinder 30. For example, as shown in FIG. 2, the connecting member 51 has a columnar portion 51a at the bottom thereof, and the columnar portion 51a is fitted into the groove hole 35 of the movable cylinder 30 described above. The cylindrical protrusion 51b of the connecting member 51 is integrally formed with an annular protrusion 51b extending in an annular shape along the outer peripheral direction thereof and having an arcuate curved surface in the vertical direction. In short, the vertical cross section of the annular protrusion 51b is semicircular or substantially semicircular.

The slot 35 of the movable cylinder 30 has a square opening, and when the columnar portion 51a is fitted into the slot 35, any vertex of the annular protrusion 51b comes into point contact with the inner wall surface of the slot 35. (See arrow A in FIG. 2). The point where the apex of the annular protrusion 51b contacts the slot 35 corresponds to a centering point (point of action) that exerts a pressing force on the movable cylinder 30.

Note that the projection of the connecting member 51 that is fitted into the movable cylinder 30 and exerts a pressing force does not necessarily have to be annular as a whole as in the present embodiment. In order to allow the movable cylinder 30 to move forward and backward, for example, hemispherical projections capable of making point contact with the front and rear inner wall surfaces of the slot 35 are formed at least at two positions on the front and rear surfaces of the cylindrical portion 51a. May be. Such a hemispherical projection may have a circular arc-shaped cross-sectional profile taken along an arbitrary line passing through the centering point. Further, such an annular protrusion 51b or a hemispherical protrusion does not need to be in contact with the inner wall surfaces of the front and rear of the groove hole 35 at the same time, and in consideration of thermal expansion of the member, dimensional error during manufacturing, etc. It is preferable to have Furthermore, it is more preferable that the apex (point of action or centering point) of the annular protrusion 51b or the hemispherical protrusion exists on the flow line of the movable cylinder 30, which is the central axis of the chamber.

As described above, the movable cylinder 30 and the connecting member 51 are coupled with each other with a gap δ between the groove hole 35 and the columnar portion 51a as shown in the enlarged circle of FIG. The presence of this clearance absorbs an undesired bending stress or the like caused by a mechanical error or the like when the movable cylinder 30 reciprocates, so that the stress particularly on the neck portion of the connecting member 51 or the like is absorbed. Concentration is eliminated, and damage to these movable parts can be prevented.

As shown in FIG. 4, the upper portion of the connecting member 51 is fitted and fixed in a fitting hole 50b formed in the lower portion of the T-shaped joint arm 50, for example. Further, the joint arm 50 is formed with through holes 50a, 50a for penetrating and fixing the two guide rods 45, 45 on the left and right. The “connecting member” according to the present invention may be formed by a single member in which the joint arm 50 and the connecting member 51 shown in FIG. 4 are integrated.

FIG. 5 is a plan view of a drive device 40 that reciprocates the movable cylinder 30. The drive device 40 includes a hydraulic cylinder 42, a joint arm 50, a guide rod 45, slide bearings 46, 47 and the like on a base plate 41. The two guide rods 45, 45 have the same length and diameter, are parallel to each other, and are fixed to the through holes 50 a, 50 a of the joint arm 50. The slide bearings 46 and 47 are bearings that allow the guide rod 45 to freely slide in the axial direction. That is, the guide rods 45 are slidably supported by the front and rear slide bearings 46 and 47, and the joint arm 50 is guided by the guide rods 45 and 45 in the direction of the central axes of the chambers 20 and 30. It is designed to be parallel to each other.

The rod 43 of the hydraulic cylinder 42 is connected to one side surface of the joint arm 50. By switching the pressure oil supplied to the hydraulic cylinder 42 to extend and retract the rod 43, the joint arm 50 reciprocates while being guided by the guide rods 45, 45.

As described above, the hot chamber casting apparatus 10 is configured such that the rear end portion of the plunger nozzle 20 moves forward and backward in the chamber 31 in association with the reciprocating movement of the movable cylinder 30 by the driving device 40. By simplifying the structure of these main chambers, mechanical failure such as galling of the movable part is reduced, durability is increased, and eventually the life of the device can be extended.

Particularly, in this embodiment, the hydraulic cylinder 42 of the drive device 40 and the movable cylinder 30 of the chamber have a structure in which the hydraulic cylinder 42 moves in translation via the connecting member 51. By design, the drive device 40 and the chamber are arranged in parallel, but in reality, mechanical stress in manufacturing may cause bending stress or galling in the movable part.
However, in the present embodiment, as described above, the connecting member 51 is configured to make point contact with the movable cylinder 30 to exert a pressing force, so that the connecting portion between the movable cylinder 30 and the connecting member 51 is sufficient. Clearance can be secured. As a result, unnecessary bending stress or the like that may occur in the movable portion including the connecting member 51 and the movable cylinder 30 is absorbed, and damage to the members and galling can be prevented.

The casting operation by the hot chamber casting apparatus 10 having such a configuration is as follows. First, in order to introduce the molten metal W into the chamber 31, the rod 43 of the hydraulic cylinder 42 is retracted and the movable cylinder 30 is pulled down, as shown in FIG. At this time, the volume of the chamber chamber 31 is increased and the pressure is reduced, so that the molten metal is introduced into the chamber chamber 31 through the gap between the inner surface of the chamber chamber 31 and the outer surface of the plunger nozzle 20.

Next, as shown in FIG. 7, the rod 43 of the hydraulic cylinder 42 is extended to push up the movable cylinder 30. As a result, the inside of the chamber chamber 31 is pressurized, and the molten metal is injected into the cavity 73 in the mold via the molten metal passage 21 of the plunger nozzle 20. Then, after the molten metal in the cavity 73 is cooled and solidified, as shown in FIG. 8, the hydraulic cylinder 75 is retracted and the movable mold 72 is separated from the fixed mold 71 to obtain a cast product M having a predetermined shape. To be

The hydraulic cylinder 42 of the drive device 40 preferably has a stroke sufficient to separate the plunger nozzle 20 and the movable cylinder 30. By doing so, the plunger nozzle 20 and the movable cylinder 30 can be separated while the chambers 20 and 30 are immersed in the molten metal W. Further, as shown in FIG. 9, the chamber may be taken out from the molten metal W of the pod 60 by lowering the elevating means 80. Accordingly, the metal material remaining in the chamber chamber 31 of the movable cylinder 30 and the melt passage 21 of the plunger nozzle 20 can be easily and sufficiently drained.

As described above, according to the hot chamber casting apparatus 10 of the present embodiment, the structures of the chambers 20 and 30 can be simplified, and durability and life can be improved. In particular, since the connecting member 51 connecting the drive device 40 and the chambers 20 and 30 that move in parallel with each other is configured to make point contact with the movable cylinder 30 to exert a pressing force, the mechanical dimensions of these movable portions are conventionally. It is possible to effectively prevent stress concentration, damage, galling, etc. on a member that may occur due to an error or the like.

Further, by arranging the central axes of the chambers 20 and 30 obliquely, it is possible to reduce the injection pressure as compared with the conventional vertical chamber. As a result, the mechanical load on the chamber can be reduced, and the durability can be improved and the life can be extended. It also enables the casting of relatively thin precision parts.

Further, at least the entire chamber chamber 31 of the movable cylinder 30 is made to reciprocate while being immersed in the molten metal W, so that metal oxides or the like floating on the surface of the molten metal W do not enter the chamber chamber 31. As a result, it is possible to prevent impurities from mixing into the molten metal material and ensure the purity of the die-cast product.

Further, the chambers 20 and 30 can be taken out from the molten metal W in a state where the plunger nozzle 20 and the movable cylinder 30 are separated. This makes it possible to drain the metal material remaining in the chambers 20 and 30 well and improve the maintenance workability.

10 Hot Chamber Casting Device 20 Plunger Nozzle 21 Hot Water Channel 22 Flange 30 Movable Cylinder 31 Chamber Chamber 35 Groove Hole 40 Drive Unit 41 Base Plate 42 Hydraulic Cylinder 43 Rod 45 Guide Rod 50 Joint Arm 51 Connecting Member 51a Cylindrical Part 51b Annular Protrusion 60 Pod (molten bath)
71 Fixed mold 72 Movable mold 73 Cavity 80 Lifting means W Molten metal M Cast product

Claims (8)

A pod for storing molten metal that is a molten metal material ,
A plunger nozzle having a molten metal passage for injecting the molten metal stored in the pod into a mold;
The base end of the plunger nozzle is inserted into the chamber chamber, by reciprocating in a state where at least the entire said chamber chamber is immersed in the molten metal, and introducing the molten metal into the chamber chamber and through said water passage And a movable cylinder that injects into the mold
A drive device that outputs a pressing force for reciprocating the movable cylinder ;
A connecting member for connecting the drive device and the movable cylinder, the connecting member transmitting the pressing force output by the drive device to the movable cylinder ,
A hot chamber casting apparatus configured such that the connecting member comes into point contact with the movable cylinder to exert the pressing force on the movable cylinder. The hot chamber casting apparatus according to claim 1, wherein a flow line of the movable cylinder and a direction of a central axis of the plunger nozzle coincide with each other, and an action point of the pressing force exists on a line of the central axis. The connecting member has a columnar portion, a protrusion portion is formed that extends annularly along the outer peripheral direction of the columnar portion and has a curved surface with a substantially semicircular cross section,
The hot chamber casting apparatus according to claim 1, wherein the apex of the protrusion is in point contact with the movable cylinder. The hot chamber casting apparatus according to claim 3, wherein the cylindrical portion of the connecting member is fitted into the slot of the movable cylinder. The hot chamber according to claim 3, wherein a groove hole is formed in a direction orthogonal to a flow line direction of the movable cylinder, and the columnar portion of the connecting member is fitted into the groove hole of the movable cylinder. Casting equipment. The hot chamber casting apparatus according to claim 4, wherein a gap is formed between the groove hole of the movable cylinder and the cylindrical portion of the connecting member. The central axis of the chamber forms a predetermined angle with respect to the horizontal, and the movable cylinder is installed with the plunger nozzle side facing upward so as to be immersed in the molten metal stored in the pod . The hot chamber casting apparatus according to any one of 6 above. The hot chamber casting apparatus according to claim 7, wherein the predetermined angle is within a range of 10 to 40° with respect to the horizontal.

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