JP3592287B2 - Structure of injection sleeve for die casting machine - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a horizontally arranged injection sleeve for a die casting machine, and more particularly to a structure of an injection sleeve capable of preventing the injection sleeve from being thermally deformed in the vicinity of the dropped portion by a molten metal dropped from a molten metal pouring port.
[0002]
[Prior art]
In vacuum casting in a die casting machine, when the gap between the inner peripheral surface of the injection sleeve and the outer peripheral surface of the plunger tip exceeds a predetermined value, there is a problem that the molten metal is inserted and the effect of the suction force is reduced. FIG. 2A shows an injection sleeve 2 for injecting and filling the molten metal into a pair of molds 1 and a plunger tip 3 for extruding the molten metal supplied into the injection sleeve 2 through a pouring port 7 to the left. The plunger rod 4 screwed and fixed to the plunger tip 3 and the rod 5 of the injection cylinder unit 8 via the coupling 6 are shown. 2B, the center axes of the plunger rod 4 and the injection sleeve 2 do not coincide with each other. That is, when there is misalignment, a part of the outer periphery of the plunger tip 3 wears the inner peripheral surface of the injection sleeve 2. Indicates the status. The inventor of the present invention previously described in Japanese Patent No. 3180280 that, due to the misalignment of the injection sleeve 2 and the plunger tip 3 and the plunger rod 4 as described above, the inner peripheral surface of the injection sleeve was worn by initial wear, and the suction force in vacuum casting was reduced. In order to solve the problem of reduction, a method has been proposed in which the plunger tip and the plunger rod are supported by a spherical surface and the screw portion of the plunger tip and the plunger rod has a play. However, Japanese Patent No. 3180280 does not specifically propose measures against thermal deformation of the injection sleeve itself. On the other hand, conventionally, the cooling of the injection sleeve is performed as shown in FIG. 3, but this is only performed by cooling the tip of the injection sleeve to cool and solidify the biscuit BSQ remaining at the left tip of the injection sleeve 9. Cooling is based on the same concept as cooling a mold. In the example of FIG. 3, the molten metal arrives in the vicinity X near the falling portion of the molten metal every shot, and it is necessary to inject and fill the molten metal into the mold cavity. There was no. Therefore, the thermal deformation of the injection sleeve due to the heat of the molten metal is different between the vicinity X of the falling portion and the vicinity of the upper pouring port, and as a result, the thermal deformation d warps upward. Such thermal deformation of the injection sleeve is not preferable as described above, and generates a gap between the injection sleeve and the plunger tip.
[0003]
That is, in the prior art, since the molten metal poured into the injection sleeve is located on the lower surface of the inner circumference of the injection sleeve under gravity, a large temperature difference occurs between the lower side and the upper side of the injection sleeve main body at that portion, Due to the thermal deformation due to the difference in thermal expansion based on this, it becomes a bow shape, and the sliding characteristic of the plunger tip with the inner peripheral surface of the injection sleeve deteriorates. As a countermeasure, it is conceivable that the clearance between the injection sleeve and the plunger tip is increased in advance to increase the fitting white at the connecting portion of the plunger rod to absorb this, but the initial wear of the plunger tip is inevitable. However, this further increases the gap, and the molten metal is inserted into the gap, which significantly reduces the life of the injection sleeve and the plunger tip. The present inventor considers that thermal deformation is unavoidable in the above-described conventional injection sleeve, which causes wear of the inner peripheral surface of the injection sleeve, and in order to improve this point, the injection sleeve itself has to be improved. He came to the idea that it was absolutely necessary to keep thermal deformation low.
[0004]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a structure of an injection sleeve for a die casting machine, which can suppress a thermal deformation due to a molten metal poured into the injection sleeve.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the structure of the injection sleeve for a die casting machine according to the present invention is an injection sleeve that is disposed horizontally in a fixed die plate of the die casting machine, and a molten metal pouring port is provided at an upper portion thereof. A hole for a cooling medium flow path is formed in the body of the injection sleeve in the axial direction in the vicinity of the dropping portion of the molten metal that is formed and supplied from the molten metal pouring port, and is provided in the hole for temperature control. A helical groove is formed on the outer peripheral surface of the pipe, and a helical cooling medium passage is formed with the inner peripheral surface of the hole in contact with the outer peripheral surface of the pipe, and the pipe is formed at both ends of the pipe. A groove is provided for communicating the inside with the spiral groove, and a part of the cooling medium flowing inside the pipe is diverted to the spiral cooling medium passage.
[0007]
Further, the pipe is preferably formed of a material having a lower thermal conductivity than the injection sleeve body.
[0008]
In that case, a pair of the temperature control pipes is disposed substantially symmetrically with respect to a vertical line passing through the central axis of the injection sleeve in the injection sleeve main body, and each of the pipes is provided at an end of the injection sleeve on the plunger rod side. An opening for supply and discharge of a cooling medium communicating with one end of the pipe is formed, and an annular path formed for cooling the biscuit portion of the injection sleeve is formed between the other ends of the pipes. It can be configured to be connected to form a coolant circulation channel for the molten metal falling portion and the biscuit portion in the injection sleeve.
[0009]
[Action]
In the present invention, the temperature of the vicinity of the pouring port of the injection sleeve and the vicinity of the molten metal dropping portion in the vicinity of the molten metal falling portion in the injection sleeve main body so that the cooling medium flows through the flow path formed in the axial direction of the injection sleeve. It is possible to reduce the difference and reduce the thermal deformation. In particular, the flow path is constituted by a pipe for temperature control, a spiral groove is formed on the outer peripheral surface of the pipe, and a part of the cooling medium is branched from the main flow path and supplied to the spiral groove. Is made of a material having a lower thermal conductivity than the injection sleeve main body, so that the main body of the injection sleeve is not directly cooled by the cooling medium flowing through the inside of the pipe.
[0010]
In addition, a pair of temperature control pipes, which are substantially symmetrical with respect to a vertical line passing through the central axis of the injection sleeve, are provided in the injection sleeve body, and one end of each of the pipes is provided at an end of the injection sleeve on a plunger rod side. An opening for cooling medium supply and discharge communicating with the end of the injection sleeve is formed, and the flow path for cooling the biscuit portion of the injection sleeve is connected between the other ends of the pipes. The cooling and the cooling in the vicinity of the molten metal falling portion are formed as one circulation flow path, thereby simplifying the flow path of the cooling medium.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG. FIG. 1A shows a cross section along the axial direction of the injection sleeve. In FIG. 1A, reference numeral 10 denotes an injection sleeve. Reference numeral 12 denotes a fixed die plate of the die casting machine, to which the injection sleeve 10 is fixed via a spacing member 14. An opening 16 for pouring molten metal is formed in an upper portion of the injection sleeve 10. Reference numerals 18 and 20 indicated by alternate long and short dash lines indicate a plunger tip and a plunger rod, respectively. Below the injection sleeve 10, that is, below the opening 16, there is a coolant supply in the injection sleeve main body, which extends in the axial direction from the right end face, that is, the end face position s1 on the plunger rod side to the left position s2. A hole for the flow path 21 is formed from the right end face side, and a pipe 22 for temperature adjustment is disposed in this hole. Further, a hole for a passage 24 having an inner diameter of the pipe 22 is formed from the positions s2 to s3, and the passage 24 is formed in an annular passage 26 formed between the outer peripheral surface of the injection sleeve 10 and the inner peripheral surface of the spacer member 28. I understand. The annular passage 26 and the cooling annular passage 30 of the biscuit portion BSQ communicate with each other at the upper part of the injection sleeve 10 as shown in the figure. Although not shown, another discharge-side flow path is provided behind the flow path 21 in parallel with the flow path 21, and a pipe similar to the pipe 22 is provided there. Reference numeral 32 denotes a passage communicating with the rear passage corresponding to the passage 24, and communicates with the cooling annular passage 30 located below as shown by a broken line. That is, as shown in FIG. 1B viewed from the Z direction in FIG. 1A, the supply of the cooling medium is provided on the right end face of the injection sleeve 10 at a position symmetrical with respect to the vertical line 1 passing through the central axis of the injection sleeve 10. , Discharge openings 34 and 36 are formed. Therefore, the flow path 32 in FIG. 1A communicates with the left end of the opening 36. FIG. 1C shows the structure of the pipe 22 in an enlarged manner. In FIG. 1C, the inner portion of the pipe 22 is the main flow path of the cooling medium. A groove 22 </ b> A is spirally formed on the outer peripheral surface of the pipe 22, and a spiral flow path is formed by the inner peripheral surface of the injection sleeve 10. Further, the rightmost end groove 23 and the leftmost end groove 25 of the groove 22A communicate with the inside of the pipe 22, respectively. Therefore, a part of the cooling medium flowing through the main flow path branches to the rightmost end groove 23 as shown in FIG. Through the path, it returns from the leftmost groove 25 to the main flow path inside the pipe again. The material of the pipe 22 is preferably a stainless steel material having a lower thermal conductivity than the material of the injection sleeve. The reason is that the inner peripheral surface of the injection sleeve 10 is cooled only by the cooling medium flowing through the spiral flow path formed by the spiral grooves 22A, and is not directly cooled by the cooling medium flowing through the main flow path. That is, the vicinity of the molten metal falling portion of the injection sleeve 10 is not excessively cooled. Also, by variously changing the groove shape of the pipe 22, the number and the pitch of the spiral grooves, the contact area with the inner peripheral surface of the injection sleeve 10, in other words, the heat exchange rate can be made variable. 1 can be prepared and replaced via the openings 34 and 36 in FIG. 1B.
[0012]
In the embodiment shown in FIG. 1 described above, a part of the cooling medium supplied from the opening 34 for supplying the cooling medium reaches the rightmost groove 23 from the inside of the pipe 22 and passes through the spiral groove 22A. The inner peripheral surface of the main body of the injection sleeve 10 is directly cooled while reaching the left end groove 25, and the cooling medium returning to the main flow path from the groove 25 again passes through the annular path 26 via the passage 24 and the biscuit. The injection sleeve body in the vicinity of the portion BSQ is cooled, and reaches the discharge opening 36 from the passage 32 through the other return pipe (not shown). In this case, the pipe 22 is made of, for example, a stainless steel material having a lower thermal conductivity than the main body of the injection sleeve 10 so that the cooling medium flowing through the main flow path does not directly cool the main body of the injection sleeve 10.
[0013]
【The invention's effect】
The structure of the injection sleeve for a die casting machine according to claim 1 of the present invention is an injection sleeve which is disposed horizontally in a fixed die plate of the die casting machine, and has a molten metal pouring port formed on an upper portion thereof. Since a cooling medium passage is formed in the main body of the injection sleeve in the vicinity of the falling portion of the molten metal supplied from the molten metal pouring port, the vicinity of the molten metal falling portion of the injection sleeve is appropriately cooled to suppress thermal deformation thereof, and the plunger tip is provided. And the inner peripheral surface of the injection sleeve can be reduced to prevent the insertion of the molten metal, prevent the effect of the vacuum suction force in vacuum casting from being diminished, and further, as the cooling medium passage, the inside of the injection sleeve body A temperature adjusting pipe disposed in a hole formed in the axial direction of the pipe, wherein a spiral groove is formed on an outer peripheral surface of the pipe. A spiral cooling medium passage is formed with the inner peripheral surface of the hole in contact with a surface, and grooves are formed at both ends of the pipe to communicate the inside of the pipe and the spiral groove, respectively. Since a part of the flowing cooling medium is divided into the spiral cooling medium passage, the temperature can be adjusted so that the vicinity of the molten metal falling portion of the injection sleeve by the cooling medium is not excessively cooled.
[0015]
Further, in the invention described in claim 2, since the pipe is formed of a material having a lower thermal conductivity than the injection sleeve main body, the temperature adjustment is not directly affected by the flow rate of the cooling medium flowing through the main flow path. The degree of cooling can be adjusted by the number, pitch, and shape of the spiral grooves.
[0016]
Further, in the invention according to claim 3, a pair of temperature control pipes substantially symmetrical with respect to a vertical line passing through a central axis of the injection sleeve are disposed in the injection sleeve main body, and a plunger rod of the injection sleeve is provided. An opening for supplying and discharging a cooling medium communicating with one end of each pipe is formed at a side end , and an annular portion for cooling a biscuit portion of the injection sleeve is provided between the other ends of the pipes. Since the cooling medium circulation flow path is formed by connecting the passages, cooling in the vicinity of the biscuit portion and cooling in the vicinity of the molten metal falling portion, which are conventionally performed, can be handled by one circulation flow path. Since the port and discharge port are provided at the end of the injection sleeve on the plunger rod side, there is no need to provide a cooling medium supply port, discharge port, or pipe near the biscuit as in the conventional case, simplifying the structure of the surrounding area. An effect that can be of.
[Brief description of the drawings]
FIGS. 1A and 1B show the structure of an injection sleeve according to an embodiment of the present invention, in which FIG. 1A is an axial longitudinal sectional view taken along the line AA (FIG. 1B) of the injection sleeve, and FIG. () Shows a view on arrow Z in (a), and (c) is a detailed vertical sectional view of a pipe for temperature control.
2A and 2B show a conventional injection sleeve, in which FIG. 2A shows a structure of the injection sleeve and its surroundings, and FIG. 2B shows a case where there is misalignment between the injection sleeve, the plunger tip and the plunger rod. is there.
FIG. 3 is a view for explaining that the vicinity of a molten metal falling portion in a conventional injection sleeve causes thermal deformation due to the molten metal that has fallen.
[Explanation of symbols]
Reference Signs List 10 Injection sleeve 12 Fixed die plate 16 Melt pouring port 18 Plunger tip 20 Plunger rod 22 Pipe 22A for temperature adjustment Helical grooves 24, 32 Passages 26, 30 Annular paths 34, 36 Openings

Claims (3)

An injection sleeve disposed horizontally in a fixed die plate of a die casting machine, the upper portion of which has a molten metal pouring port formed therein, and the injection sleeve is provided near a dropping portion of molten metal supplied from the molten metal pouring port. A hole for a cooling medium flow passage is formed in the body in the axial direction, and a temperature adjusting pipe is provided in the hole, and a spiral groove is formed on an outer peripheral surface of the pipe. A spiral cooling medium passage is formed with the inner peripheral surface of the hole in contact with the pipe, and grooves are formed at both ends of the pipe to communicate the inside of the pipe and the spiral groove, respectively, and flow inside the pipe. The injection sleeve for a die casting machine, wherein a part of the cooling medium is diverted to the spiral cooling medium passage. 2. The structure of an injection sleeve for a die casting machine according to claim 1, wherein the pipe is formed of a material having a lower thermal conductivity than the injection sleeve body. 3. The injection control device according to claim 1, wherein a pair of the temperature control pipes is disposed substantially symmetrically with respect to a vertical line passing through a central axis of the injection sleeve in the injection sleeve main body. Defines an opening for supplying and discharging a cooling medium communicating with one end of each pipe, and is formed between the other ends of the pipes for cooling the biscuit portion of the injection sleeve. A structure of an injection sleeve for a die casting machine, wherein an annular path is connected to form a cooling medium circulation flow path for the molten metal falling section and the biscuit section in the injection sleeve.

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