Low-damping type matrix overflow discharging vacuum gypsum mold forming mold and casting method

Abstract

The invention discloses a low-damping type matrix overflow-discharging vacuum gypsum mold forming mold and a casting method, the low-damping type matrix overflow-discharging vacuum gypsum mold forming mold comprises a mold body and overflow-discharging capillary tubes, and the overflow-discharging capillary tubes are inserted into the mold body in a sliding mode; the multiple overflow discharging capillary tubes are arranged in an array mode. According to the low-damping type matrix overflow discharging vacuum gypsum mold forming mold and the casting method, the overflow discharging capillary tubes are arranged, so that the overflow discharging capillary tubes and the gypsum mold are combined into a whole in the gypsum mold forming process, the demolding resistance of the gypsum mold is reduced, and the gypsum mold is complete and not prone to being damaged; and in the gypsum mold dewaxing roasting process, the phenomena of overflow hole blockage and crack do not occur, so that the final finished product quality is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of special casting, and relates to a low-damping matrix overflow vacuum gypsum type forming mold and a casting method. Background Art

[0002] For thin-walled precision castings with densely distributed small diameter (small diameter refers to a diameter not greater than 2mm and a height-to-diameter ratio greater than 20) heat sink pin structures, an aluminum mold (or wax mold) is generally used to pour a gypsum mold and then vacuum cast after baking. A small row of overflow holes is made on the aluminum mold (or wax mold) for the heat sink pins. After the mold is taken out, exhaust and slag discharge channels are formed to solve the problem of difficult forming of the heat sink pins.

[0003] However, the sample mold with small overflow holes has strong adhesion and is difficult to remove during demolding; during the dewaxing and roasting process of the gypsum mold, the overflow holes are not only easily blocked, but small cracks and micro bubbles will appear in the holes, resulting in uneven hole walls and greatly increasing the resistance to exhaust and slag removal. Even if vacuum casting is used, the heat dissipation needles with very small diameters still have insufficient casting defects, and the qualified rate is less than 50%.

[0004] In order to solve the above problems, a plaster molding mold and a casting method are needed to avoid the problem that the cavity of the heat sink pin part is incomplete after the plaster mold is demolded, thereby affecting the quality of the final product. Summary of the invention

[0005] In view of this, the present invention provides a low-damping matrix overflow vacuum gypsum mold forming mold and casting method. By arranging the overflow capillary, the overflow capillary and the gypsum mold are combined with the gypsum mold to form a whole during the molding process, thereby reducing the demolding resistance of the gypsum mold. The gypsum mold is intact and not easy to be damaged. During the dewaxing and roasting process of the gypsum mold, there is no blockage or cracking of the overflow hole, thereby improving the quality of the final product.

[0006] The invention discloses a low-damping matrix overflow vacuum gypsum forming mold, comprising a mold body and overflow capillaries, wherein the overflow capillaries are slidably plugged into the mold body; a plurality of the overflow capillaries are arranged in an array.

[0007] Furthermore, the mold body includes a mold base plate and a mold frame, the mold frame is arranged on the top surface of the mold base plate to form a mold cavity with an open top and a closed bottom and surroundings, and the overflow capillary array is arranged in the mold cavity.

[0008] Furthermore, it also includes a positioning top plate, which is detachably mounted on the top surface of the mold frame for closing the mold cavity, and the positioning top plate is provided with positioning holes for positioning and limiting the overflow capillaries, and the number of the positioning holes is the same as the overflow capillaries.

[0009] Furthermore, the mold body is provided with a workpiece mold, and the workpiece mold has a plurality of vertically arranged heat dissipation pin molds. The number of the overflow capillaries is equal to the heat dissipation pin molds, and the plurality of the overflow capillaries are arranged one by one on the top surface of the heat dissipation pin molds.

[0010] Furthermore, the positioning holes are arranged in one-to-one correspondence with the heat dissipation pin-shaped molds, and the bottom surface of the overflow capillary tube passes through the positioning holes and overlaps the top surface of the heat dissipation pin-shaped mold.

[0011] Furthermore, the overflow capillary has an overflow channel that penetrates along the axial direction, the diameter of the overflow channel is smaller than the diameter of the heat dissipation pin-shaped mold, and the difference between the diameter of the overflow channel and the diameter of the heat dissipation pin-shaped mold is 0.3-0.6.

[0012] Furthermore, the top surface of the mold frame extends upward in the vertical direction to form a limiting boss, the limiting boss is provided with a positioning opening, the positioning top plate is provided with a positioning strip at a position corresponding to the positioning opening, and the positioning strip of the positioning top plate is clamped in the positioning opening.

[0013] Furthermore, the positioning top plate is also provided with a pouring port, and the pouring port is arranged to avoid the positioning hole.

[0014] The present invention also discloses a vacuum plaster casting method, which is based on the aforementioned low-damping matrix overflow vacuum plaster molding die, and specifically comprises the following steps:

[0015] S1. Processing and manufacturing positioning top plate;

[0016] S2. Install the positioning top plate to the mold body, and insert multiple overflow capillaries one by one into the positioning holes, until the bottom surface of the overflow capillary overlaps the top surface of the heat dissipation needle mold;

[0017] S3. Modulate the gypsum slurry and inject the modulated gypsum slurry into the cavity of the mold body from the injection port of the top plate until the cavity of the mold body is filled with the modulated gypsum slurry; after the gypsum slurry hardens, demold and remove the gypsum mold integrally formed by the overflow capillary;

[0018] S4. The gypsum mold is put into the furnace for baking, and after it is taken out of the furnace, it is blown clean with compressed air.

[0019] Beneficial effects of the present invention:

[0020] The present invention provides a low-damping matrix overflow vacuum plaster mold forming mold and casting method. By setting overflow capillaries, the overflow capillaries and the plaster mold are combined to form a whole during the molding process, which reduces the demoulding resistance of the plaster mold, and the plaster mold is intact and not easy to be damaged. There is no blockage of overflow holes and cracks in the dewaxing and roasting process of the plaster mold, thereby improving the quality of the final product. At the same time, by embedding a matrix overflow capillary with a smooth inner wall during the grouting process of the plaster mold, the exhaust and slag removal efficiency of the fine needle structure is greatly improved, the vacuum suction effect is amplified, the gas and slag at the front end of the liquid flow are fully discharged, and the process of filling the front end of the needle-shaped body with molten metal is extended to achieve complete filling of the needle body. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 An exploded isometric view of the present invention;

[0022] Figure 2 It is an isometric view of the assembly structure of the present invention;

[0023] Figure 3 It is a main partial view of the present invention;

[0024] Figure 4 for Figure 3 A partial enlarged view of the middle A;

[0025] Figure 5 It is a schematic structural diagram of the gypsum type of the present invention;

[0026] Figure 6 It is a front cross-sectional view of the gypsum mold of the present invention;

[0027] Figure 7 for Figure 6 A partial enlarged view of point B in the middle. DETAILED DESCRIPTION

[0028] It should be noted that, in the description of this specification, the terms "upper", "lower", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. The head and tail as well as the front and back in this embodiment are based on the order of the flow of the medium, that is, the medium that flows first is the front and the first, which can be understood by those skilled in the art and will not be elaborated here.

[0029] As shown in the figure, an embodiment of the present invention discloses a low-damping matrix overflow vacuum gypsum type forming mold, including a mold body and an overflow capillary 2, wherein the overflow capillary 2 is slidably plugged into the mold body; the overflow capillary 2 is provided with a plurality of overflow capillaries, and the plurality of overflow capillaries 2 are arranged in an array. The overflow capillary 2 in this embodiment is a metal tube. The arrangement of the overflow capillary 2 enables the overflow capillary 2 to be combined with the gypsum mold 12 to form a whole during the molding process of the gypsum mold 12, thereby reducing the demoulding resistance of the gypsum mold 12, and the gypsum mold 12 is intact and not easy to be damaged. During the dewaxing and roasting process of the gypsum mold 12, there is no blockage of the overflow hole and cracks, thereby improving the quality of the final finished product. In this embodiment, the mold body includes a mold base plate 1 and a mold frame 4, and the mold frame 4 is arranged on the top surface of the mold base plate 1 to form a mold cavity with an open top and a closed bottom and surroundings, and the overflow capillary 2 array is arranged in the mold cavity. The sliding insertion of the overflow capillary 2 in the present embodiment means that its installation method is this kind of sliding insertion, and it is movably arranged in the mold cavity, rather than being fixed in the mold body by other structures. This arrangement ensures that after the gypsum mold 12 is formed, the overflow capillary 2 can be easily demolded and removed together with the gypsum mold 12, making demolding easier.

[0030] In this embodiment, a positioning top plate 3 is also included. The positioning top plate 3 is detachably mounted on the top surface of the mold frame 4 for closing the mold cavity. The positioning top plate 3 is provided with positioning holes 7 for positioning and limiting the overflow capillaries 2. The number of the positioning holes 7 is the same as that of the overflow capillaries 2. In this embodiment, the mold body is provided with a workpiece mold 5. The workpiece mold 5 has a plurality of vertically arranged heat dissipation pin molds 6. The number of the overflow capillaries 2 is equal to that of the heat dissipation pin molds 6. The plurality of the overflow capillaries 2 are arranged on the top surface of the heat dissipation pin molds 6 in a one-to-one correspondence. In this embodiment, the positioning holes 7 are arranged in a one-to-one correspondence with the heat dissipation pin molds 6. The bottom surface of the overflow capillaries 2 passes through the positioning holes 7 and overlaps the top surface of the heat dissipation pin molds 6. As shown in the figure, the number of the heat dissipation pin-shaped mold 6, the overflow capillary 2 and the positioning hole 7 in this embodiment is the same, and the positions of the heat dissipation pin-shaped mold 6 and the positioning hole 7 correspond one to one, that is, a positioning hole 7 is correspondingly provided directly above each heat dissipation pin-shaped mold 6, so that the overflow capillary 2 is inserted into the mold cavity through the positioning hole 7 and falls on the top surface of the heat dissipation pin-shaped mold 6, and is kept in a vertical state. In this way, when pouring gypsum liquid to make the gypsum mold 12, it is ensured that the overflow capillary 2 is vertical in the formed gypsum mold 12. The positioning hole 7 of this embodiment positions the overflow capillary 2 in the radial direction. After the overflow capillary 2 is inserted, its bottom surface overlaps and falls on the top surface of the heat dissipation pin-shaped mold 6, and the top of the overflow capillary 2 is limited in the positioning hole 7, so that the overflow capillary 2 will not shake in the radial direction. The workpiece mold 5 refers to a mold that conforms to the workpiece to be cast. The workpiece mold 5 is arranged so that the plaster mold 12 will have a cavity that is consistent with the shape of the workpiece after molding, so as to facilitate subsequent casting.

[0031] In this embodiment, the overflow capillary 2 has an overflow channel that runs through the axial direction, that is, the overflow capillary 2 is a hollow tubular structure, the hollow part of which is the overflow channel, and the diameter of the overflow channel is smaller than the diameter of the heat dissipation needle mold 6, and the difference between the diameter of the overflow channel and the diameter of the heat dissipation needle mold 6 is 0.3-0.6. Taking the heat dissipation needle mold 6 as 2mm as an example (that is, the diameter of the heat dissipation needle after molding is 2mm), the diameter of the overflow channel is 1.4-1.7mm, preferably 1.55±0.05mm. Such a design not only ensures the overflow effect, but also ensures that the quality of the heat dissipation needle of the final product meets the standards.

[0032] In this embodiment, the top surface of the mold frame 4 extends upward in the vertical direction to form a limiting boss 10, and the limiting boss 10 is provided with a positioning opening 11. The positioning top plate 3 is provided with a positioning strip 9 at a position corresponding to the positioning opening 11, and the positioning strip 9 of the positioning top plate 3 is snapped into the positioning opening 11. As shown in the figure, the limiting boss 10 in this embodiment is symmetrically arranged with two, and only two symmetrical ones are arranged to facilitate the taking and installation of the positioning top plate 3. The main positioning and limiting are achieved by snapping the positioning strip 9 into the positioning opening 11. The two positioning openings 11 in this embodiment are respectively located at the middle position of the limiting boss 10.

[0033] In this embodiment, the positioning top plate 3 is further provided with a pouring port 8, and the pouring port 8 is arranged to avoid the positioning hole 7. As shown in the figure, the positioning top plate 3 is rectangular, and the pouring port 8 is arranged at one corner thereof.

[0034] The present invention also discloses a casting method based on the vacuum gypsum mold 12, which is based on the aforementioned low-damping matrix overflow vacuum gypsum mold 12 forming mold, and the method specifically includes the following steps:

[0035] S1. Processing and manufacturing the positioning top plate 3; taking a piece of transparent organic glass with a thickness of 10 to 15 mm according to the size of the drawing, and CNC processing the positioning holes 7.

[0036] S2. Install the positioning top plate 3 to the mold body, and insert multiple overflow capillaries one by one through the positioning holes 7 until the bottom surfaces of the overflow capillaries overlap the top surface of the heat dissipation needle mold 6; slide the overflow capillaries freely downward along the positioning holes 7 on the positioning top plate 3 and fall into the top of the opposite heat dissipation needle aluminum mold.

[0037] S3 modulates the gypsum slurry, and injects the modulated gypsum slurry into the cavity of the mold body from the injection port 8 of the positioning top plate 3 until the cavity of the mold body is filled with the modulated gypsum slurry; after the gypsum slurry hardens, demold and remove the gypsum mold 12 integrally formed by the overflow capillary;

[0038] S4. The gypsum mold 12 is put into the furnace for baking, and after it is taken out of the furnace, the gypsum mold 12 is blown clean with compressed air. Blowing clean the gypsum mold 12 means blowing clean the mold cavity of the gypsum mold 12 (including the workpiece mold cavity corresponding to the workpiece mold 5 and the heat dissipation needle mold cavity 13 corresponding to the heat dissipation needle mold) and the floating dust in the overflow channel of the overflow capillary with compressed air, so that the gypsum mold 12 with a low damping overflow system having a smooth tube wall is obtained.

[0039] Subsequently, the cleaned gypsum mold can be assembled with other gypsum mold components as needed and then put into the vacuum tank for pouring. Vacuum pouring is conducive to the filling of thin-walled and fine-diameter long-flow needle-like structures with molten metal. By embedding a matrix overflow capillary with a smooth inner wall during the gypsum mold grouting process, the exhaust and slag removal efficiency of the fine needle structure is greatly improved, the vacuum suction effect is amplified, the gas and scum at the front end of the liquid flow are fully discharged, and the process of filling the metal liquid at the front end of the needle-like body is extended to achieve complete filling of the needle body. At the same time, compared with the prior art, after the gypsum mold grouting hardens, the overflow capillary is separated with the gypsum mold, which reduces the demoulding resistance, and the gypsum mold is intact and not easy to be damaged; there is no blockage or cracking of the overflow hole during the dewaxing and roasting process of the gypsum mold. The gypsum mold of the present invention can realize the precision casting of thin-walled castings with densely distributed fine heat dissipation needle structures (diameter of about 2mm, height-to-diameter ratio greater than 20), eliminate the defect of insufficient pouring, and obtain a casting with a dense structure at the front of the needle tip without slag inclusions and a clear outline, and the product qualification rate is increased to more than 95%.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A low damping matrix overflow vacuum gypsum type forming mold, characterized in that: The invention comprises a mold body and overflow capillaries, wherein the overflow capillaries are slidably plugged into the mold body; a plurality of the overflow capillaries are arranged in an array.

2. The low damping matrix overflow vacuum gypsum type forming mold according to claim 1, characterized in that: The mold body comprises a mold base plate and a mold frame, wherein the mold frame is arranged on the top surface of the mold base plate to form a mold cavity which is open at the top and closed at the bottom and around, and the overflow capillary array is arranged in the mold cavity.

3. The low damping matrix overflow vacuum plaster type forming mold according to claim 2, characterized in that: It also includes a positioning top plate, which is detachably mounted on the top surface of the mold frame for closing the mold cavity. The positioning top plate is provided with positioning holes for positioning and limiting the overflow capillaries, and the number of the positioning holes is the same as the overflow capillaries.

4. The low damping matrix overflow vacuum plaster type forming mold according to claim 3, characterized in that: The mold body is provided with a workpiece mold, and the workpiece mold has a plurality of vertically arranged heat dissipation pin molds. The number of the overflow capillaries is equal to that of the heat dissipation pin molds, and the plurality of the overflow capillaries are arranged one by one on the top surface of the heat dissipation pin molds.

5. The low damping matrix overflow vacuum plaster type forming mold according to claim 4, characterized in that: The positioning holes are arranged in one-to-one correspondence with the heat dissipation pin-shaped molds, and the bottom surface of the overflow capillary tube passes through the positioning holes and overlaps the top surface of the heat dissipation pin-shaped mold.

6. The low damping matrix overflow vacuum plaster type forming mold according to claim 5, characterized in that: The overflow capillary has an overflow channel that penetrates along the axial direction. The diameter of the overflow channel is smaller than the diameter of the heat dissipation pin-shaped mold. The difference between the diameter of the overflow channel and the diameter of the heat dissipation pin-shaped mold is 0.3-0.

6.

7. The low damping matrix overflow vacuum plaster type forming mold according to claim 5, characterized in that: The top surface of the mold frame extends upward in the vertical direction to form a limiting boss, the limiting boss is provided with a positioning opening, the positioning top plate is provided with a positioning strip at a position corresponding to the positioning opening, and the positioning strip of the positioning top plate is clamped in the positioning opening.

8. The low damping matrix overflow vacuum plaster type forming mold according to claim 7, characterized in that: The positioning top plate is also provided with a pouring port, and the pouring port is arranged to avoid the positioning hole.

9. A casting method based on a vacuum gypsum mold, the method is based on the low damping matrix overflow vacuum gypsum mold molding mold according to any one of claims 1 to 8, characterized in that: The method specifically comprises the following steps: S1. Processing and manufacturing positioning top plate; S2. Install the positioning top plate to the mold body, and insert multiple overflow capillaries one by one into the positioning holes, until the bottom surface of the overflow capillary overlaps the top surface of the heat dissipation needle mold; S3. Modulate the gypsum slurry and inject the modulated gypsum slurry into the cavity of the mold body from the injection port of the top plate until the cavity of the mold body is filled with the modulated gypsum slurry; after the gypsum slurry hardens, demold and remove the gypsum mold integrally formed by the overflow capillary; S4. The gypsum mold is put into the furnace for baking, and after it is taken out of the furnace, it is blown clean with compressed air.

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