Stable mold shell pouring device for investment casting three-chamber vacuum furnace

Abstract

The invention discloses a stable pouring mold shell device for an investment casting three-chamber vacuum furnace, which comprises a sleeve with a bottom and a mold shell tray, a screw rod is fixedly mounted at the axis of the inner bottom surface of the sleeve with the bottom, a screw rod sleeve is fixedly mounted at the axis of the lower surface of the mold shell tray, and the screw rod of the sleeve with the bottom is sleeved with the screw rod sleeve of the mold shell tray in a threaded manner; two support rods are vertically fixed on the upper surface of the mold shell tray along the diameter direction and close to the circumferential edge, and a group of sleeve clamping units are mounted on each support rod; each set of sleeve clamping unit is connected with a set of top plate clamping unit, and each set of top plate clamping unit is provided with two baffles. The invention belongs to the technical field of investment casting, smelting and pouring, and solves the problems that in the ascending process of a casting chamber in the prior art, a mold shell placed on a lifting platform is prone to inclining or toppling due to vibration, and the working efficiency is affected.

Description

Technical Field

[0001] The invention belongs to the technical field of investment casting smelting and pouring, and relates to a pouring stabilizing mold shell device for an investment casting three-chamber vacuum furnace. Background Art

[0002] When pouring the mold shell under vacuum in the three-chamber vacuum melting furnace for investment casting, the melting chamber always maintains a vacuum state. The casting chamber is located below the melting chamber, and there is a lifting platform at the bottom of the casting chamber that can be lifted to the melting chamber. During pouring, a stainless steel sleeve with a bottom is placed on the lifting platform of the casting chamber. The bottom of the sleeve with a bottom is paved with dry sand, and a layer of asbestos is laid on the dry sand, and the mold shell is placed on the asbestos. Close the door of the casting chamber and start to evacuate. When the vacuum degree of the casting chamber and the melting chamber is the same, open the gate valve, and the lifting platform rises to send the mold shell to the melting chamber to complete the pouring.

[0003] However, it often happens that the mold shell tilts or falls due to vibration during the rising process of the lifting platform of the casting room, resulting in failure of normal casting; especially for mold shells with high height and small bottom surface, it is more likely to tilt or fall. In this case, it is necessary to lower the lifting platform of the casting room again, close the gate valve, break the vacuum of the casting room, and rearrange the mold shell, resulting in reduced production efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a pouring stabilizing mold shell device for a three-chamber vacuum furnace for investment casting, which solves the problem in the prior art that during the rising process of the casting chamber, the mold shell placed on the lifting platform is easily tilted or tipped due to vibration, thereby affecting work efficiency.

[0005] The technical solution adopted by the present invention is a pouring stable mold device for a three-chamber vacuum furnace for investment casting, comprising a bottom sleeve and a mold tray, a screw is fixedly installed on the axis of the inner bottom surface of the bottom sleeve, a screw sleeve is fixedly installed on the axis of the lower surface of the mold tray, and the screw sleeve of the mold tray is threadedly sleeved on the screw of the bottom sleeve; two support rods are vertically fixed along the diameter direction near the circumference of the upper surface of the mold tray, and a group of sleeve clamping units are installed on each support rod; each group of sleeve clamping units is connected to a group of top plate clamping units, and each group of top plate clamping units is installed with two baffles.

[0006] The invention is a pouring stable mold shell device for an investment casting three-chamber vacuum furnace, and its characteristics are:

[0007] The bottom sleeve is made of phosphor bronze and the screw is made of stainless steel.

[0008] The bottom sleeve is made of phosphor bronze, the screw sleeve is made of stainless steel; the support rod is made of stainless steel.

[0009] The structure of the sleeve clamping unit is that it includes a sleeve with a seat and a locking plate. One end of the sleeve with a seat is an arc-shaped clamping seat. The arc-shaped clamping seat of the sleeve with a seat and the locking plate are clamped on the support rod relatively, and the locking is achieved by two bolt locking assemblies; the other end of the sleeve with a seat is sleeve one, and the front section of the sleeve one is symmetrically opened along the diameter with a pair of L-shaped guide grooves, and a spring is arranged in the sleeve one.

[0010] The structure of the top plate clamping unit is as follows: it includes a top plate, a sleeve 2 is vertically fixed in the middle part of the top plate, a pin is fixed at the free end of the sleeve 2, the sleeve 2 extends into the sleeve 1, both ends of the pin extend out of the L-shaped guide groove of the sleeve 1 and a pair of hooks are symmetrically fixed, one end of the spring is fixed at the lower end of the inner cavity of the sleeve 1, and the other end of the spring extends into the sleeve 2 and is fixedly connected with the pin;

[0011] Through grooves are symmetrically opened along the sleeve at the two longitudinal sections of the top plate, and U-shaped slots are respectively connected to the two through grooves of the top plate. Each U-shaped slot is fixed to the top plate through a set of bolt locking assemblies passing through the through groove. The U-shaped slot is fixedly connected to the baffle plate at an angle of 90°, and the baffle plate and the top plate are perpendicular to each other.

[0012] The beneficial effect of the present invention is that by adjusting the height of the mold tray and the sleeve clamping unit, the baffles on both sides of the top plate are positioned to the appropriate position matching the mold. When pouring, the mold is placed in the center of the mold tray, and the top plate hook is manually loosened. The top plate supports the mold under the extension drive of the spring, and the baffles on both sides of the mold play a protective role. When pouring in a three-chamber vacuum melting furnace, the mold plays a good stabilizing role in the process of rising from the casting chamber to the pouring chamber. The device of the present invention is simple and convenient to operate, and effectively prevents the lifting platform of the casting chamber from causing the mold to tilt or tip over during the rising process, which can effectively improve the pouring efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the bottom sleeve and the screw in the device of the present invention;

[0014] Figure 2 It is a structural schematic diagram of the mold shell tray and the screw sleeve in the device of the present invention;

[0015] Figure 3 It is a cross-sectional view of the connection state between the bottom sleeve and the mold shell tray in the device of the present invention;

[0016] Figure 4 It is a schematic diagram of the installation of the support rod on the mold shell tray in the device of the present invention;

[0017] Figure 5 It is a schematic diagram of the L-shaped guide groove structure of the sleeve clamping unit in the device of the present invention;

[0018] Figure 6It is a schematic diagram of the structure of the bolt locking assembly in the device of the present invention;

[0019] Figure 7 It is a structural schematic diagram of a set of sleeve clamping units in the device of the present invention;

[0020] Figure 8 It is a structural schematic diagram of a group of top plate clamping units in the device of the present invention;

[0021] Fig. 9 It is a schematic diagram of the integral connection between the sleeve clamping unit and the top plate clamping unit in the device of the present invention;

[0022] Fig.10 It is a schematic diagram of the structure of the baffle and the U-shaped slot in the device of the present invention;

[0023] Fig.11 It is a schematic diagram of the pin hook in the device of the present invention being buckled on the horizontal side of the L-shaped guide groove, and the spring being in a compressed state;

[0024] Fig.12 It is a schematic diagram of the pin hook in the device of the present invention being buckled at the end of the long side of the L-shaped guide groove, and the spring being in a relaxed state;

[0025] Fig.13 It is a schematic diagram of the relaxed state of the device of the present invention before the mold shell is placed;

[0026] Fig.14 It is a schematic diagram of the state of the device of the present invention after the mold shell is put in and clamped.

[0027] In the figure, 1. screw, 2. screw sleeve, 3. support rod, 4. L-shaped guide groove, 5. locking plate, 6. hook; 7. top plate; 8. sleeve two, 9. spring, 10. baffle, 11. U-shaped slot, 12. mold shell, 13. sleeve with bottom, 14. mold shell tray, 15. bolt locking assembly, 16. sleeve with seat, 17. pad, 18. sleeve one. DETAILED DESCRIPTION

[0028] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Reference Figure 1 , Figure 2 , Fig.13 The structure of the present invention is that it includes a bottom sleeve 13 and a mold tray 14, a screw 1 is fixedly installed on the inner bottom surface of the bottom sleeve 13, a screw sleeve 2 is fixedly installed on the lower surface of the mold tray 14, and the screw sleeve 2 of the mold tray 14 is threadedly sleeved on the screw 1 of the bottom sleeve 13 to form an integral body. Figure 3Two support rods 3 are vertically fixed on the upper surface of the mold tray 14 along the diameter direction near the circumference, and a group of sleeve clamping units are installed on each support rod 3; each group of sleeve clamping units is connected to a group of top plate clamping units (top plate 7) through a spring 9, and each group of top plate clamping units (top plate 7) is installed with two baffles 10, a total of four baffles 10 surround and clamp the mold 12 and the pads 17 on both sides thereof.

[0030] See Figure 1 , Figure 3 The bottom sleeve 13 is made of phosphor bronze, and a screw 1 is fixed (welded) at the axial position of the bottom of the inner cavity of the bottom sleeve 13, and the screw 1 is made of stainless steel. The outer diameter of the bottom sleeve 13 is Φ400-500mm, the height is 200-400mm, and the wall thickness is 4-6mm; the diameter of the screw 1 is Φ30-40mm, and the height is 100-200mm.

[0031] See Figure 2 , Figure 3 The mold shell tray 14 is made of phosphor bronze. A stainless steel screw sleeve 2 is fixed (welded) at the axial position of the lower surface of the mold shell tray 14. The internal thread of the screw sleeve 2 matches the screw 1 of the bottom sleeve 13. The mold shell tray 14 and the bottom sleeve 13 are threadedly engaged. Rotating the mold shell tray 14 can adjust the height of the mold shell tray 14 in the inner cavity of the bottom sleeve 13.

[0032] See Figure 4 Two stainless steel support rods 3 are symmetrically fixed (welded) on the edges of the discs on both sides of the plane of the mold shell tray 14.

[0033] See Figure 5 , Figure 6 , Figure 7 The structure of the sleeve clamping unit is, including a seat sleeve 16 and a locking plate 5, one end of the seat sleeve 16 is an arc-shaped clamping seat, the arc-shaped clamping seat of the seat sleeve 16 and the locking plate 5 are clamped on the support rod 3, and the locking is achieved by two bolt locking assemblies 15; the other end of the seat sleeve 16 is a sleeve 18, and the front section of the sleeve 18 is symmetrically penetrated along the diameter with a pair of L-shaped guide grooves 4, and a spring 9 is arranged in the sleeve 18.

[0034] See Figure 8 , Fig. 9The structure of the top plate clamping unit is as follows: it includes a top plate 7, a sleeve 2 8 is vertically fixed (welded) on the middle part of the top plate 7, a pin is fixed on the free end of the sleeve 2 8, the sleeve 2 8 extends into the sleeve 1 18, both ends of the pin extend out of the L-shaped guide groove 4 of the sleeve 18 and a pair of hooks 6 are symmetrically fixed (welded), one end of the spring 9 is fixed on the lower end of the inner cavity of the sleeve 18, the other end of the spring 9 extends into the sleeve 2 8 and is fixedly connected with the pin, the pin pulls the spring 9 on the one hand and limits the extension position of the spring 9 on the other hand;

[0035] See Fig.10 , Fig.11 , Fig.12 , through grooves are symmetrically opened along the sleeve 8 at the two longitudinal sections of the top plate 7, and U-shaped grooves 11 are respectively connected to the two through grooves of the top plate 7. Each U-shaped groove 11 is fixed to the top plate 7 through a group of bolt locking assemblies 15 passing through the through groove. The U-shaped groove 11 is fixedly connected to the baffle 10 at an angle of 90°, and the baffle 10 and the top plate 7 are perpendicular to each other; the baffle 10 and the U-shaped groove 11 are made of stainless steel, and each baffle 10 is installed at a through groove position of the top plate 7. The distance between the two baffles 10 is adjusted to a suitable position to adapt to the size of the membrane shell sample and the pad 17.

[0036] The mold tray 14 has a diameter of Φ300-400 mm and a thickness of 10-20 mm.

[0037] The diameter of the support rod 3 is Φ10-20 mm, and the height is 400-500 mm.

[0038] The width of the L-shaped guide groove 4 is 3 to 5 mm.

[0039] The length of the pin is 40 to 60 mm, and the diameter is Φ18 to 28 mm.

[0040] The hook 6 has a diameter of Φ2-4 mm and a length of 20-30 mm.

[0041] The outer diameter of the sleeve 18 is Φ20-30 mm, the length is 80-100 mm, and the wall thickness is 2-3 mm.

[0042] The outer diameter of the sleeve 8 is Φ20-30mm, the length is 200-300mm, and the wall thickness is 3-5mm.

[0043] The through groove has a length of 50 to 80 mm and a width of 5 to 8 mm.

[0044] The baffle 10 has a length of 50 to 100 mm, a width of 50 to 100 mm, and a wall thickness of 3 to 5 mm.

[0045] Reference Fig.13 , Fig.14 The working process of the device of the present invention is:

[0046] A. Place the device of the present invention on the lifting platform of the casting chamber of the three-chamber vacuum melting furnace, and lay a layer of dry sand with a thickness of 50 to 100 mm on the bottom of the bottom sleeve 13 to prevent the mold shell 12 from breaking and leaking the molten metal, which is convenient for cleaning;

[0047] B. According to the actual height of the mold shell 12, the mold shell tray 14 is rotated to adjust the height of the upper surface of the mold shell tray 14 to a suitable position;

[0048] C. Manually pull the two hooks 6 on the pin shaft of each top plate clamping unit, and buckle the hooks at the horizontal corner buckle of the L guide groove of the sleeve clamping unit, so that the spring 9 is in a squeezed state, and most of the sleeve 2 8 extends into the sleeve 1 18. Fig.11 ;

[0049] D. Loosen the bolt locking assembly 15 of the two through slots and the U-shaped slot 11 of the top plate 7 of each top plate clamping unit, and adjust the relative positions of the four baffles 10 so that the mold shell is centered;

[0050] E. Place the mold shell at the center of the mold shell tray 14, manually loosen the two symmetrical pin hooks of the two sleeve clamping units, and driven by the spring 9, the sleeve 2 8 pops out from the sleeve 1 18 and extends longer, and the relative distance between the two top plates 7 is reduced to support the mold shell;

[0051] F. Adjust the baffles 10 on both sides of the top plate 7 to be close to the pads 17 on both sides of the mold shell, then firmly fix all four bolt locking assemblies 15, lock the U-shaped slots 11, and fix the four baffles 10 to achieve stable clamping of the mold shell;

[0052] G. Process of casting the mold shell. After the casting of the mold shell is completed, manually pull the two symmetrical hooks 6 on the pin shaft, buckle the hooks 6 at the corner buckles of the guide groove of the sleeve L, retract the spring 9, and release the mold shell from the top plate 7;

[0053] H. Use the mold fork to take out the mold after pouring.

[0054] Example 1

[0055] A three-chamber vacuum melting furnace is used to cast a certain type of retaining ring product. The dimensions of the mold shell 12 are 80 mm in width, 110 mm in length, and 300 mm in height, and the mold shell height is relatively high.

[0056] Using the structure of the prior art, a stainless steel sleeve with a bottom is placed on the lifting platform of the casting chamber before pouring, dry sand is laid on the bottom of the inner cavity of the sleeve with a bottom, a layer of asbestos is laid on the dry sand, and the mold shell 12 is placed on the asbestos. According to statistics, 200 strings of mold shells 12 were poured, and tilting occurred 32 times and tipping occurred 21 times, and the probability of tilting or tipping was 26.5%. After tilting or tipping occurs, it is necessary to lower the mold shell 12 from the pouring chamber to the casting chamber again, close the gate valve, break the vacuum in the casting chamber, open the casting chamber furnace door, re-place the mold shell 12, and then close the casting chamber furnace door again, evacuate to the same level as the smelting chamber, open the gate valve and raise the lifting platform of the casting chamber to the smelting chamber again, which obviously affects the production efficiency. At the same time, re-placing the mold shell will also cause the temperature of the mold shell 12 to drop, and the process is difficult to guarantee, which affects the stability of the smelting and pouring process.

[0057] For mold shells 12 of the same structure, the device of the present invention is used to stabilize the mold shell 12. The device of the present invention is placed on the lifting platform of the casting room, and the height of the mold shell tray 13 and the height of the top plate clamping unit on the support rod 3 are adjusted respectively. The mold shell 12 of a certain guard ring product is placed on the mold shell tray 14. By manually loosening the hook, the spring 9 stretches the two top plates 7 to support the mold shell 12 at the same time, and the baffles 10 on both sides are adjusted to be close to the pads on both sides of the mold shell 12 to stabilize the mold shell 12. The operation is very convenient. The device of the present invention is used to stabilize the mold shell 12. According to statistics, 200 strings of mold shells 12 were cast without tilting or tipping of the mold shell 12, which greatly improves the casting efficiency and also ensures the process stability of the casting process.

[0058] Example 2

[0059] When a three-chamber vacuum melting furnace is used to cast a certain type of positioner product, the mold shell dimensions are 120mm in width, 250mm in length, and 150mm in height.

[0060] The structure of the prior art is adopted. During pouring, a stainless steel sleeve with a bottom is placed on the lifting platform of the casting chamber. Dry sand is laid on the bottom of the inner cavity of the sleeve with a layer of asbestos. The mold shell 12 is placed on the asbestos. When placed, the bottom of the mold shell 12 contacts the bottom surface through four evenly distributed small cylinders (each small cylinder has a diameter of Φ20mm and a height of 10mm). Therefore, the contact area is small and it is easy to tilt when placed. It is necessary to support thin bricks at the bottom of the mold shell to make the mold shell upright. It is necessary to constantly adjust bricks of different thicknesses to place the mold shell 12, which is extremely inconvenient to operate. During the rising process of the lifting platform of the casting chamber, due to vibration and other reasons, the thin bricks will become loose and easily cause the mold shell 12 to tilt. According to statistics, 150 strings of mold shells 12 were poured, and tilting occurred 35 times, with a probability of tilting of 23.3%.

[0061] For the mold shells of the same product, the device of the present invention is used to stabilize the mold shell 12. The operation process is very convenient and there is no need to support thin bricks at the bottom of the mold shell. According to statistics, 150 strings of mold shells 12 were poured without tilting, which ensures the process stability of the pouring process and avoids the decrease in production efficiency caused by repeated placement of the mold shells 12. The pouring efficiency is greatly improved and the difficulty of operation for workers is reduced.

[0062] Example 3

[0063] When a three-chamber vacuum melting furnace is used to cast a certain type of outer ring product, the mold shell dimensions are 50mm in width, 150mm in length, 350mm in height, and the cross-sectional diameter of the bottom of the mold shell sprue is approximately Φ50mm.

[0064] With the structure of the prior art, when placing the mold shell, the bottom sprue with a diameter of Φ50mm contacts the bottom surface, and the contact area is small. The mold shell 12 cannot stand on its own and needs to be supported by bricks on both sides. It is extremely inconvenient for workers to operate, and they need to constantly adjust the position of the bricks to place the mold shell 12, and it often requires more than two workers to operate at the same time to complete. During the rising process of the lifting platform of the casting room, due to vibration and other reasons, the bricks will shake, which may cause the mold shell to tilt or fall. According to statistics, out of 100 strings of mold shells 12, there were 17 tilts and 15 falls, and the probability of tilting or falling was 32%.

[0065] For the mold shells of the same product, the device of the present invention is used to stabilize the mold shells. Only one operator is needed to complete the placement of the mold shells 12. The operation process is very convenient. According to statistics, after pouring 100 strings of mold shells, there was no tilt or fall of the mold shells 12, which greatly improved the pouring efficiency and reduced the difficulty of the workers' operation.

Claims

1. A casting stable mold shell device for a three-chamber vacuum furnace for investment casting, characterized in that: The mold tray (14) comprises a bottom sleeve (13) and a mold shell tray (14); a screw (1) is fixedly installed on the axis of the inner bottom surface of the bottom sleeve (13); a screw sleeve (2) is fixedly installed on the axis of the lower surface of the mold shell tray (14); the screw sleeve (2) of the mold shell tray (14) is threadedly sleeved on the screw (1) of the bottom sleeve (13); two support rods (3) are vertically fixed on the upper surface of the mold shell tray (14) along the diameter direction and close to the circumference, and each support rod (3) is installed with a group of sleeve clamping units; each group of sleeve clamping units is connected to a group of top plate clamping units, and each group of top plate clamping units is installed with two baffles (10).

2. The pouring stable mold shell device for investment casting three-chamber vacuum furnace according to claim 1, characterized in that: The bottom sleeve (13) is made of phosphor bronze, and the screw rod (1) is made of stainless steel.

3. The pouring stable mold shell device for investment casting three-chamber vacuum furnace according to claim 1, characterized in that: The bottom sleeve (13) is made of phosphor bronze, the screw sleeve (2) is made of stainless steel, and the support rod (3) is made of stainless steel.

4. The pouring stable mold shell device for investment casting three-chamber vacuum furnace according to claim 1, characterized in that: The structure of the sleeve clamping unit is that it includes a seat sleeve (16) and a locking plate (5), one end of the seat sleeve (16) is an arc-shaped clamping seat, the arc-shaped clamping seat of the seat sleeve (16) and the locking plate (5) are clamped on the support rod (3) relative to each other, and locking is achieved by two bolt locking assemblies (15); the other end of the seat sleeve (16) is a sleeve one (18), the front section of the sleeve one (18) is symmetrically opened along the diameter and has a pair of L-shaped guide grooves (4), and a spring (9) is arranged in the sleeve one (18).

5. The pouring stable mold shell device for investment casting three-chamber vacuum furnace according to claim 1, characterized in that: The structure of the top plate clamping unit is as follows: it comprises a top plate (7), a sleeve (8) is vertically fixed to the middle part of the top plate (7), a pin is fixed to the free end of the sleeve (8), the sleeve (8) extends into the sleeve (18), both ends of the pin extend out of the L-shaped guide groove (4) of the sleeve (18) and a pair of hooks (6) are symmetrically fixed thereto, one end of a spring (9) is fixed to the lower end of the inner cavity of the sleeve (18), and the other end of the spring (9) extends into the sleeve (8) and is fixedly connected to the pin; Through grooves are symmetrically formed along the sleeve (8) at two longitudinal sections of the top plate (7), and U-shaped grooves (11) are respectively connected to the two through grooves of the top plate (7). Each U-shaped groove (11) is fixed to the top plate (7) through a group of bolt locking assemblies (15) passing through the through groove. The U-shaped groove (11) is fixedly connected to the baffle plate (10) at an angle of 90 degrees, and the baffle plate (10) and the top plate (7) are perpendicular to each other.

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