WO1980001657A1

WO1980001657A1 - Die casting method

Info

Publication number: WO1980001657A1
Application number: PCT/JP1979/000034
Authority: WO
Inventors: H Suzuki; S Hashimoto
Original assignee: Nippon Denso Co; H Suzuki; S Hashimoto
Priority date: 1979-02-14
Filing date: 1979-02-14
Publication date: 1980-08-21
Also published as: JPS5930503B1; DE2953436C2; DE2953436T1; GB2055315B; GB2055315A

Abstract

Die casting method in which a molten metal is injected into a die cavity (30) for cast products through a sprue (31) and also applied with pressure by means of a pressure plunger (36) through a pressure channel (17) communicating with the die cavity (30) at a location other than the sprue (31). According to this invention, upon the application of pressure, the molten metal in the pressure channel (17) may be extruded into the die cavity to form an expanded flow so that the application of pressure is always carried out with a stable pressure. A part of the die-cast product solidified in the die cavity (30), which part is substantially opposed to the pressure channel (17), is cut along the moving direction of the plunger (36) across a sectional area larger than that of the pressure channel (17), in order to remove a portion where surface defects and/or segregation may be apt to grow so that the strength and/or workability of the die-cast products is/are deteriorated. Further, holes or grooves caused by said cutting are used for parts of configuration of products. This method is adapted for the mass production of products such as housings of compressors, pumps and the like, which is to be used under high-pressure conditions or to be subjected to precision working.

Description

Details

(1) Name of the invention Dycast method

2 Technical Field The present invention relates to a die casting method.] More specifically, the present invention relates to a method in which molten metal is discharged from a discharge passage into a mold space for product binding. The pressurized plunger also pressurizes the molten metal filled in the mold space from the pressurized passage that communicates with the mold space at a position different from the outlet passage. It relates to the die-storage method described above.

3 Background Art Conventionally, a pressurized passage communicating with the mold space at a position different from the discharge passage is provided, and the molten metal in the pressurized passage is formed in the mold space by a pressurized plunger. Japanese Patent Publication No. Sho 51-1289817 proposes a method of dying force which is extruded to the surface. In the publication of Japanese Patent Publication No. 11-2987-17, the pressurizing passage is shown in Fig. 1.

The molten metal in the pressurized passage that is pushed out by the advance of the pressurized plunger 36 is once pressurized.

Three- ,. Aisle! ) The passageway was narrowed down by a communication passage with a reduced cross-sectional area, and then pushed out into the mold space 30. And when the inventor experimented with the method of pressurizing in this manner, the force needed to advance the pressurized plunger 36 was large. It has been difficult to maintain a stable pressing force because of the variation.

According to the study by the inventor, it is clear that

It was considered that large variations in the pressing force would occur for the following reasons. In other words, after the molten metal has been filled in the pressurizing passage 17, a certain amount of time may occur by any time before the pressurized plunger 36 starts to move forward. The surface of molten α has solidified during this predetermined time. Therefore, when the pressurized plunger 36 is advanced, it actually pushes out the solidified layer ^ and moves forward.]? The solidified layer in 17 is blocked by the communication passage 17a, and it is presumed that the solidified layer ^ is sheared in a very complicated form.

Therefore, when the pressurized plunger 36 is advanced, a large resistance is generated due to the shearing of the solidified layer, and therefore, the pressure is always stable. It is thought that the molten metal in the pressurized passage 17 cannot be pushed out by the press.

4 Disclosure of invention-,-Λ VI70 ' Based on the results of this study, the present inventor first considered that the pressurized passage communicating with the mold space at a position different from the discharge passage D and the flow of the molten metal expanding Immediately after devising a method of dying to apply pressure by being pushed into the mold space, the size of the part that communicates with the pressurizing passage after the mold space has been devised. Is a pressurized plan? The cross-sectional area of the pressurized passage will increase over the entire area in the direction of the noya's travel.]? The pressurized passage will be set at 5 ^ The extruded molten metal will flow into the mold space. When the molten metal was extruded into the mold space, it was pressurized as shown in Fig. 5.

Then, the present inventor actually pushes the molten metal in the pressurized passage into the mold space while forming an enlarged flow, thereby using a method to actually remove the die cast. At the same time, it was possible to force the molten metal into the pressure passage with a stable pressure.

However, in this case, where the molten metal in the pressurized passage flows into the mold space as an expanded flow, surface defects and segregation are likely to occur. The diecastrolo C manufactured using this method has the strength and workability of the solidified part of the mold space near the part that communicates with the pressurized passage. Was found to be inferior.

The present invention has been emplaced in view of the above-mentioned research results, and is a pressurized passage.]) When the molten metal is pushed into the mold space, the molten metal forms an -expanded flow. By performing the pressurization in this way, it is possible to make the riser of the molten metal filled in the mold space with a constantly stable pressurizing force, space Die cast product solidified in the inside Ρ By cutting the surface of the pressurized passage near the surface chipping and segregation-prone parts, the die cast product is actually The purpose is to maximize the quality of the city to be used and to enjoy it.

Then, in the method of the present invention, in order to achieve this purpose, specifically, the steps described below are temporally and sequentially performed.

1. The movable mold is brought into contact with the fixed mold, and the molten metal is discharged into the mold space for product production and the mold space, and a different position from the discharge passage and the discharge passage. And forming a pressurized passage communicating with the mold space in the first step.

2. A second step in which the molten metal is discharged from the discharge passage into the mold space and the pressurized passage at a predetermined discharge pressure, and the mold space and the pressurized passage are filled with the molten metal. ·

3. A third step in which the molten metal filled in the pressurizing passage is pressed to the mold space side while forming an expanding flow by pressurizing the molten metal.

4. After the molten metal filled in the mold space has solidified, the fourth step is to release the hot water from the pressurized passage.

5. The movable mold is fixed.]? The fifth step of separating the solidified dies in the mold space ejection passage and the pressurized passage.

6. Da .. It's the best product! ), Removes the solidified part in the injection passage and is a die-cast product]), removes the solidified part in the pressurized passage, and solidifies in the mold space. The part facing the pressurizing passage is the cross-sectional area of the pressurizing passage.] Is a large 断面 cross-sectional area in the direction of travel of the pressurizing plunger.

In addition, according to the method of the present invention, since it is always possible to make a hot water, it is possible to reduce the number of nests that adversely affect the airtightness and strength of the material. It has an excellent effect that it can produce ΡΡ in large quantities.

Also, in order to remove areas where surface defects and segregation are likely to occur. 製品 Products used in places where &: is added, and need to be subjected to precision machining. It can be used as a casting method. 5 It has an excellent effect. In particular, in the present invention, a solidified solid in the mold space □

After the roll, the part almost opposite to the pressurized passage is called the pressurized passage! ) Is large. The holes or grooves formed as a result of the removal are used as part of the product shape because they are removed in the direction of travel of the ranger. It has an excellent effect when it can be done.

5 Brief description of the drawings Fig. 1 is a cross-sectional view showing the main parts of the device used for the conventional die-cut method, and Fig. 2 is the device used for carrying out the present invention method. 3 and 4 show the pressurizing passage 17, the mold space 30, and the basin 32 shown in FIG. 2, respectively. Fig. 3 is a cross-sectional view. Is the most retracted state, and FIG. 4 shows the state in which the pressure plunger 36 has advanced the most. FIG. 5 is a cross-sectional view for explaining the solidified layer ^ generated in the pressurized passage 17 and the like, and FIG. 6 is a diagram of the device shown in FIG. 1. Cross-sectional view, Fig. 7 is a side view of Fig. 6, Fig. 8 is a reference photograph showing the structure of a die-formed product with surface defects, Fig. 9 is a die with segregation A reference photograph showing the structure of the cast product, and Fig. 10 is a reference photo showing the structure of the product manufactured by the method of the present invention. 6 Form of Saigon for carrying out the invention In the following, the method of the present invention will not be described for the embodiment of Sagami, but the apparatus used for carrying out the present invention will be described in the embodiment shown in the figure. O 5fe ^ In the figure, 1 is a fixing stand for the equipment, which is fixed on the floor of the factory via an embedded bolt (not shown). Reference numerals 2 and 3 denote projection cylinder holders fixed to the fixed channel π 1, which hold the projection cylinder 4 fixedly. On the cylindrical inner surface 4 a of the projection cylinder 4, the projection piston 5 is held in a sliding position, and openings D are provided at both ends of the projection cylinder 4. In response to the hydraulic pressure of the first and second signal hydraulic pipes 6, 7), the ejection piston 5 can be displaced in the ejection cylinder 4 in the left and right directions in the figure. It is about.

Note that the signal oil pressure is input from the hydraulic pump (not shown).

,, "0 Hydraulic pressure switching valve made via solenoid valve 9

As a result, one of the first and second signal hydraulic pipes 6 and 7 is selectively supplied, and is pushed by the discharge piston 5. The discharged oil in the discharge cylinder 4 is the signal pressure on the side to which the signal pressure is not supplied. If. 6,

7 and output pipe 10 via hydraulic switchover knob 9

0 Send to hydraulic pump side not shown]). Also, 1 1 is the 1st signal hydraulic pump. 6 With a pressure switch provided in the middle, the hydraulic pressure in the first signal pipe 6 is increased to a predetermined pressure (for example, with respect to the maximum value of the ejection pressure described later).

(The pressure will be about 5 to 80% of the pressure.) When it becomes Ji, apply the electric power to the hydraulic switching vanoreb 42 described later.

It is 5.

Then, the displacement of the ejection piston 5 is transmitted to the ejection flange 13 via the ejection rod 12, and the ejection flange 13 is transmitted to the ejection flange 13.

Is designed to slide in the emission sleeve 14 left and right in the figure. 15 is the molten metal port J,

After the side of 14, the projection head. It is provided at a position where it opens when the flange 13 is retracted most (the state shown in FIG. 2). The aluminum melter shown in FIG. Molten alloys, magnesium alloys, zinc alloys, and other molten metals are supplied from the hot water supply port 15 into the injection sleeve 14.

-- Accordingly, the discharge sleeve 14 covers a part of the discharge passage of the molten metal.

16 is a fixed support fixed to the fixed base 1

C. PI iFO No> dx. _T Although the mold 18 is fixedly held, only the one provided at the left end of the tightening rod 22 is shown in FIG. 1, but actually it is also provided at the right end of the tightening rod 22. It has been. The fixed mold 18 has a precision mold shape, and for reasons such as enhancing maintainability, etc., the fixed mold 18 made of DAILY 铸 iron (FCD55) is used. Block: Formed separately with I9 and stationary core 20 made of hot work tool steel (SKD61)] ?, this stationary block 19 and stationary core 2 0 is connected with a hexagon socket head socket 21. Note that the above-mentioned emission sleeve 14 penetrates through the fixed support 16 and the fixed block 9 and opens to the end face of the fixed block 19. What is going on.

Also, two fastening rods 2.2.22 are fixed to both sides below the fixed support 16 at J] ?, and the fastening rods 22 penetrate the movable support 23. are doing . The movable support 23 is supported by the tightening rods 22 in a tight and slidable state so that the movable support 23 can slide on the fixed base 1 in the left and right directions in the figure. It can be displaced by the driving force of a piston that does not work.

The movable support 23 has a side clamp plate 24! : The movable type 26 is fixed via the lower clamping plates 25, 25. The movable type 26 is also fixed in the same manner as the fixed type 18 described above. It is formed by connecting a movable block 27 made of iron (-FGD55) and a movable core 28 made of hot tool steel (SKD61) with a bolt 29. ing .

G'MPI V / iPO Then, not shown, the movable support 23 is displaced by the driving force of the piston, so that the movable mold 26 is brought into close contact with the fixed mold 18, and this is fixed. The two molds 18, 26 are the products of the company, and the mold space 30, the ejection passage 31 for injecting the molten metal into the mold space 30, and the ejection passage 31. Forms a pressurized passage 17 communicating with the mold space 30 at another position.] Also, the joint surface between the fixed mold 18 and the movable mold 26 is formed. At the specified location, there is a gap of about 0.1 Fiber from 0.1 recommended car, and it is pushed out by the molten metal that has been discharged from the discharge passage 31. An air vent 33 for allowing air in the mold space 30 to escape is formed. In addition, the gate on the mold space 30 side of the discharge passage 31 is a gate 34 to narrow down the passage, and the molten metal supplied from the discharge passage 31 is formed at a high speed. As a result, it is projected into the mold space 30.

Reference numeral 35 denotes a pressurized sleeve which is press-fitted and fixed to the center of the movable core 28 so as to face a position substantially at the center of the mold space 30. (SKD 61) is formed into a cylindrical shape. Into this pressurized sleeve 35, a pressurized plunger 36 made of hot-rolled steel (SKD61) is inserted so as to be tightly slidable. -] ?, the pressurizing passage 17 is formed from the inner surface of the pressurizing sleeve 35 to the end face of the pressurizing bridge 36 by the space on the forward side of D. ing . Then, the molten metal filled in the pressurizing passage 17 by the pressurizing flange 36 is opposed to the pressurizing passage 17 in the mold space. Ρί 3 2) It is pushed out to the side. The pressurized plunger 36 is composed of two materials 36a and 36b. For maintenance, only the part that slides inside the pressurized sleeve 35 must be replaced. These two materials 36a and 36b are connected by a connecting ring 37.

Figs. 3 and 4 show the pressure sleeve 35, the tip of the pressure planer 36 and the water reservoir 32, respectively. As shown in the figure, in the apparatus according to the present invention, a small amount of S-suspension (0.05 to 1.00) was found on the tip side of the inner peripheral surface of the pressurized sleeve 35 as compared with other cases. A large diameter city 35a is formed.9) When the pressure plunger 36 is pressed, the molten metal filled in the pressure passage 17 The film of the solidified layer formed on the outer surface becomes a ring-shaped barrier A, enters the large-diameter portion 35a, and pressurizes through the barrier A. In this case, the jaw 36 slides on the inner peripheral surface of the pressurized sleeve 35.

The length y of the large-diameter portion 35a is determined based on the amount of hot water supplied by the pressurizing plunger.]), The pressurizing plunger 36 Is the most retracted position 35b (the state shown in Fig. 3) more than a predetermined amount X (less than 10 騮, preferably 2 or 3 hires) Forward point 3 5) It is desirable that the length of the sleeve 35 be up to 35d. However, in practical use, the length y of the large-diameter portion 35a is changed from the last retreat position 35b of the pressurized plunger 36 to the retreat side to the tip 35d. Even so, there is no problem.

ί \ -.- ιshi '

WIPO Further, the displacement of the pressure plunger 36 does not change even at the position 35 e (the state shown in FIG. 4) where the plunger has been advanced. c is a displacement that does not protrude beyond the tip 35d of the pressurized sleeve 35, and the pressurized bridge 36 is an annealed hot water tank! ) It is possible to penetrate the city 32 and hopefully it will be better. However, if it is small, even if it protrudes from the pressurized flange tip 36c or the pressurized sleeve tip 35d5, there is no problem in practical use. It recognized .

The hot water reservoir 32 is a portion of the mold space 30 Q that is cut in a sixth step described later, and actually faces the pressurizing passage 17 after the mold space 30. Part D, the size is such that it has a cross-sectional area of about twice the cross-sectional area of the pressure passage 17 over the entire space height of the mold space 30. Review

Reference numeral 38 denotes a pressurizing piston provided on the rear end side of the pressurizing plunger 36, which slides in the pressurizing cylinder 39 to pressurize the plunger. The forward and backward displacements are reported to 36. The third and fourth signal hydraulic pipes 40 and 41 are opened to the pressurized cylinder 39 in the same manner as the ejection cylinder 4, and the hydraulic switching valve made of a solenoid valve is opened. The hydraulic pump (not shown) is driven by the knob 42.] 3 The input and output hydraulic pressures are controlled to move the pressurized piston 38 forward and backward. It has become. Then, the pressure cylinder 39 is fixed to the side tightening plate 25 by the bolt 43, and moves integrally with the movable mold 26. I'm sorry. In addition, reference numeral 44 passes through the movable block 27 and the movable core 28, and the tip of the end faces the surface of the movable core 28 and the D-shaped space 30. After moving the movable mold 26 back and opening the mold with the pin, the die-cast product solidified in the mold space 30 is removed from the movable mold 26. 5 Press and release. ] ?, via the ejector plate 45, the extruding load 46, the extruding plate 47, and the extruding rod 48. In response to the displacement of the push-out piston 49, it is displaced left and right in FIG. The left end of the push-out rod 46 is slidably inserted into a sliding hole (not shown) provided in the movable block 27]. It is possible to move in the direction. 50 is an extruding cylinder for displacing the extruding piston 49, similarly to the extruding cylinder 4 and the pressure cylinder 39. The 5th and 6th signal hydraulic pipes 51 and 52 are open.] 9, The signal pressure input from a hydraulic pump (not shown) is used to change the hydraulic switching valve made of a solenoid valve.

5 is controlled by 5 3, and the pushing out and pushing out of the piston 50 is performed 5.

Next, the die casting method of the present invention will be described in detail in the order of steps.

[First Step] Not shown, the piston is driven so that the movable support 23 is slid leftward in FIG. 6 is brought into close contact with the fixed mold 18 to form a mold space 30 for product production, an ejection passage 31, a pressurized passage 17, and an air vent 33.

f Ο ΡΙ ^{,, 5P0} Three

[Second step] Using the illustrated molten metal inlet, the molten metal is supplied to the hot water supply port 15 through the outlet 15 and into the sleeve 14 and a part of the outlet passage 31. After that, the signal hydraulic pressure is flown to the first signal hydraulic passage 6 side by the hydraulic pressure switching valve 9, and the discharge piston 5 (immediate discharge plan? ) Is advanced at a predetermined pressure determined by the signal hydraulic pressure. Its to One by the advancement of-flops run-di turbocharger 1 ₃ out elevation of the child, and out and press to Cum de Su Li over blanking flow Shi within 14 write or been shot an molten metal came out passage 3 1 side, The molten metal is injected into the mold space 30 and the pressurized passage 17 by being accelerated when passing through the gate 34, and the mold space 30 and the pressurized passage 17 are filled with the molten metal. . ¾ At this point, the pressure (injection pressure) applied to the molten metal is about 500 to 150 atm. At this time, the air that was present in the mold space 30 at the time of the ejection is trapped in the molten metal at the time of the ejection and may cause nests. An air vent 33 provided at a predetermined location after a contact portion between the movable mold 26 and the fixed mold 18 of the mold so that the air portion existing in the mold space 30 is released. are doing

[Third step] After filling the molten metal, pressurize it before the molten metal in the thirty-four gates solidifies. By moving the flange 36, the molten metal in the pressurized passage 17 ′ is extruded toward the reservoir 32 and starts to be pushed out.

In the present embodiment, this pressurization: ° The movement start time of the flange 36 is controlled by ^. Immediately, the injection of molten metal into the mold space 30 and the pressurized passage 17 is completed.

"θΛίΡ! The forward movement of the exit plunger 13 stops.], And therefore, the first signal hydraulic passage 6 supplying the signal hydraulic pressure should move the ejection plunger 13 forward. The oil pressure rises sharply 1 :. Thus, the rise in the oil pressure in the first signal pressure passage 6 is detected by the pressure switch 11, and when the pressure in the passage 6 rises above a predetermined pressure, the pressure switch is turned on. When the electric signal is applied to the hydraulic pressure switching vane valve 42, the hydraulic pressure switching valve 42 receives the signal hydraulic pressure when the electric signal is applied. Is supplied to the third signal hydraulic passage 40, so that the pressurized plunger 36 is quickly (usually about 0.5 seconds) after the firing is completed. It allows you to move forward.

Here, in a die casting device such as a groove forming device, it usually takes about 5 to 6 seconds until the molten metal in the gate 34 is completely solidified. The pressurized plunger 36 starts to move forward in a sufficiently short time compared to the time required to complete the solidification of the molten metal in the mouth 34.

9, the molten metal in the pressurizing passage 17 is pushed out into the reservoir 32, which is good! ) The molten metal filled in the mold space 30 is pushed up. -And this hot water is at least filled in the mold space 30.-Until the molten metal is solidified, in other words, the gate 3 4] ?? Maintain until the 30 side is completely solidified.

At the start of the hot water bath, the tap water is used.

Ο. Ρϊ

WIPO ",, Since the solidification has not yet occurred, the amount required for this riser is simply the amount corresponding to the solidification shrinkage of the molten metal filled in the mold space 30 and the pressurized passage 17. Not only until the gate 34 completes solidification, but the molten metal filled in the outlet passage 31 and the outlet sleeve 14 solidifies and shrinks. The amount is actually necessary.

In addition, the pressure required for this hot water should be such that at least the molten metal α filled in the pressurizing passage 17 is pushed into the water reservoir section 32. D, this minimum pressure is required to advance the pressurized flange 36 more than the discharge pressure applied by the discharge flange 13. The sliding resistance between β (illustrated in FIG. 5) of the pressurized passage 17 and the inner wall of the pressurized sleeve 35 and the inner periphery of the pressurized sleeve 35 It is necessary to increase the pressure by the amount of resistance associated with the shear deformation of the solidified layer ^ generated at the tip 35 d position. The maximum applied pressure is the maximum pressure within a range where the ejection bridge 13 is not pushed back.9 The actual pressure is applied to the ejection bracket 13. The pressure applied is from the pressurized plunger 36] 9 The applied pressure P a -D is subtracted from the pressure drop ΔP generated when the molten metal passes through the gate 34 etc. The solidified layer ^ generated at the tip of the ejection plunger 13 by this pressure-should not be sheared.

Then, the amount of hot water and the pressing force are determined within the range described in ii. In the present invention, the shape of the mold space 30 is determined. In the portion communicating with the pressurizing passage 17, the cross-sectional area in the direction perpendicular to the direction of travel of the pressurizing plunger 36 is the cross-sectional area of the inner surface of the pressurizing sleeve 35. Because of this, it is possible to always obtain the applied pressure of]?

In other words, in the present invention, as the pressurized plunger 36 advances, the molten metal in the pressurizing passage 17 expands, while the mold space 30 (water pool part 3 2) side extends. The pressure generated by the presence of the solidified layer ^ when moving forward depends on the solidified layer ^ and the pressure Only the sliding friction resistance between the inner surface of the sleeve 35 and the force required for shearing the solidified layer generated at the inner peripheral tip 35 d of the pressurized sleeve 35 is obtained. The sliding friction resistance of the former can be determined uniformly by determining the inner diameter of the pressurized sleeve 35 and the amount of advance of the pressurized bridge 36. The required force is also that the shearing of the solidified layer always occurs only at the inner peripheral tip 35d of the pressurized sleeve 35, and the shearing surface r (shown in Fig. 5) When the thickness is almost constant Therefore, it is required uniformly.

Therefore, if the pressure is set within the above-mentioned range, the dicasting by the method of the present invention is repeated many times! The same pressing force is always applied to the molten metal even if it is returned.] 9) It is always possible to obtain a dirt cast product.

[Step 4-Process] After the solidification of the gate 34 and the D-shaped space 30 is completed, the hot water will not be dispensed even if the pressurizing plunger 36 continues to pressurize it further. The hydraulic switching valve 4 2

OVPI- The signal hydraulic pressure is switched off by changing the signal hydraulic pressure, and the signal hydraulic pressure is caused to flow to the fourth signal hydraulic pipe 41 to retreat the pressurizing plunger 36. Make

The time required for solidification of the molten metal in the mold space 30 varies depending on the volume and space height of the mold space 30, etc., so the pressure plunger must be The time required for coagulation is measured by changing the time for retreating 6 to the seed force, and the time required for coagulation is determined by adding a predetermined additional time (1, 2 seconds) to this time. ), The hydraulic switching valve 42 should be switched by the timer after a lapse of time.

[Fifth step] After the pressurized plunger 36 is retracted, as shown in the drawing, the piston is driven to move the movable support 23 rightward in FIG. , And move the movable mold 26 to the fixed mold 18]. When the movable mold 26 is separated, it is sufficient that the outer surface of the molten metal on the side of the discharge passage solidifies to such an extent that the shape of the molten metal is not easily deformed. After retreating the plunger 36, the movable mold 26 is pulled apart in about 0.5 to 1.0 seconds.

When the movable type 26 is separated, the signal oil pressure is still applied to the first signal. The molten metal solidified in the ejection sleeve 14 can be pushed out from the ejection sleeve 14 by flowing to the side of the ejection sleeve 14.

• After that, the -signal oil pressure is switched off at the oil pressure switching valve 9], and the discharge plunger 13 is retracted by flowing to the second signal pipe 7 side. And then actuate hydraulic switching valve 5 3 As a result, the signal oil pressure is caused to flow to the fifth signal oil pressure pipe 51 side, and the Apex outlet 49 is moved to the left in FIG. Move this push-out piston 49, push-out rod 48, push-out plate 47, push-out rod 46, and push-out rod 46. It is transmitted to the ejector pin 44 via the ejector plate 45, and the mold space 30 and the ejection passage 3 are transmitted by the ejector pin 44. 1 and extrude the solidified dycast product in the pressurized passage 17.

[Sixth step] The dycast product manufactured by this die casting method has the shape shown in Fig. 6 and Fig. 7. The part solidified in the injection sleeve 14, the injection passage 31, and the air vent 33 (shown by hatching R in Figs. 6 and 7) ) By pressing, cutting, cutting, cutting, cutting, cutting, cutting, cutting, cutting, cutting, cutting, cutting, cutting, and cutting in the injection sleeve 14, the injection passage 31, and the air vent 3 3 It is a die-cast product with the solidified part cut out inside! ), The part of the mold space 30 that is solidified in the hot water reservoir]? 32 (the part indicated by hatching S in Figs. 6 and 7) is cut with a lathe to complete the product.

Here, the part solidified in the tub 9 part 32 is cut for the following reason. -Immediately, in the water reservoir 9 ¾ 32, the water is pushed up by the pressurized plunger 36, and the solidification proceeds under this condition. The solidified layer 9 formed in the city 32 is sheared before it grows sufficiently and surface defects occur. In particular, this surface defect is undesirable because it degrades the mechanical strength of the die cast product. In addition, since the time for crystallizing the molten metal varies depending on the type of metal, only the first crystallized metal remains, and the metal that is still in the molten state is pressurized. It will be extruded under the pressure of the ranger 36, so that segregation is likely to occur.], This segregation is the workability of Dycast products. (Machinability) is adversely affected and precision machining becomes difficult.

Fig. 8 and Fig. 9 are reference photos showing the structure of the dycast product with surface defects and the structure of the dycast product with segregation, respectively. This is what was seen in the reservoir D section 32.

Therefore, for products used especially in places where pressure resistance is required, or for products that require precision machining, the water pool should be cut. A die with the shape shown in Figs. 6 and 7

The cast an is used as a side rod and a peg of a rotating machine. In this case, the hole after cutting the reservoir 32 is passed through the rotating shaft. Use it to make it work.

¾ After the mold space 30, the molten metal filled in the places other than the part] 32 is pressed and pushed by the pressurized plunger 36. Since there is no problem, harmful components such as surface defects and segregation do not occur. FIG. 10 is a reference copy showing the structure of the solidified product part in the mold space 30 other than the basin 32 of the die-cast product manufactured by the method of the present invention.

-ΟΜΡΪ True, it is clear from Fig. 10 that products made by the method of the present invention have no defects such as nested defects and segregation.

The pressurized bridge 36 used to carry out the method of the present invention must be disposed in the movable mold 26. Of course, for example, it may be used on the fixed type 18 side, or the sliding surface of the movable type '26 and the fixed type may be slid.

7 Industrial applicability According to the method of the present invention, it is possible to press the molten metal filled in the mold space with a constantly stable pressing force, and to adversely affect the strength and processability of the product. Since the surface defects and segregation to be present are completely present in the product part, we manufacture a large number of products that are used under high pressure and that need to be precision processed. It is effective if it is used as a dying method.] For example, it is effective when used for mass production of compressors and pump housings.

wip- _w

Claims

Two

The scope of the claims ·

L The movable mold is brought into close contact with the fixed mold, and the casting space for product mirroring and the molten metal is ejected into this mold space. Forming a pressurized passage communicating with the pressurizing passage; and discharging the molten metal into the mold space and the pressurized passage at a predetermined spraying pressure to form the pressurized passage. And a second step of filling the inside of the pressurized passage with the molten metal, and pressurizing the molten metal filled in the pressurized passage.] 9 While forming an expanding flow. A third step of pushing out to the mold space side, a fourth step of releasing the hot water to the pressurizing passage after the molten metal filled in the mold space is solidified, and the movable mold The solid mold in the mold space ejection passage and the pressurized passage.

The fifth step of removing the cascade and removing the dicast product, the solidified portion in the discharge passage, and the dicast product]. The solidified portion in the pressurizing passage is removed, and the portion of the solidified portion in the mold space, which is substantially opposed to the pressurizing passage, is defined as the cross-sectional area of the pressurizing passage. A large cross-sectional area in a direction of pressurization of the pressurizing passage. The removal of the solidified portion in the mold space in the above-mentioned sixth step is based on the end face on the pressurized passage side. The pressurized passage penetrates a solidified portion in the mold space up to the end face on the opposite side.

Uu A method for dying as claimed in claim 1, characterized in that the method is to be carried out completely.

3. The pressurized passage formed in the first step is characterized in that it communicates with a substantially middle point of the mold space and a part to be formed. A dicasting method according to any one of claims 1 and 2.

OAi J