A core-pulling casting mold

Abstract

The application relates to the technical field of casting molds, in particular to a core-pulling casting mold which comprises a fixed mold and a movable mold, the fixed mold and the movable mold surround a first cavity in a mold closing state; the fixed mold comprises a first fixed part and a second fixed part; a second cavity is formed between the first fixed part and the second fixed part; a communication part is arranged on the first fixed part, the communication part is used for connecting the first cavity and the second cavity, a clearance hole is arranged on the first fixed part, the clearance hole penetrates through the communication part, the section of the communication part is enlarged at the clearance hole, so that a turbine shell mold in the second cavity can be taken out conveniently, and a first forming mold is detachably arranged in the clearance hole; the first forming mold is used for filling the clearance hole and reducing the section of the communication part to a preset casting size. The application has the effect that a complicated part body can be conveniently taken off from the fixed mold and the movable mold.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of casting molds, in particular to a core-pulling casting mold. BACKGROUND

[0002] A casting mold refers to a structure shape of a part, which is formed in advance by using other easily formed materials, and then a sand core is placed in the mold, so that a cavity with the same size as the structure of the part is formed in the sand core, and then molten metal liquid is poured into the cavity, and after the molten metal liquid solidifies, a part with the same structure as the mold shape can be formed. In modern industrial manufacturing, casting is one of the main methods to obtain metal formed part blanks.

[0003] With the increasing demand for high-performance parts in the mechanical industry, especially in the fields of automobiles, aerospace, etc., the structure of castings is becoming more and more complex, precise and lightweight. The turbocharger shell is a typical representative, which usually has a complex profile of "thick at both ends and thin in the middle", and contains a precise turbine flow channel inside. This structural feature brings great challenges to the casting process. For a turbine shell with a "dumbbell-shaped" structure with large cross-section at both ends and small cross-section in the middle, it cannot be directly demolded in the axial direction after being formed in a rigid one-piece mold, forming a so-called "reverse buckle" or "negative angle".

[0004] In order to solve this problem, the traditional process often uses a complex, multi-directional sliding block core-pulling mechanism, or uses a disposable sand core. The former mechanism is complex, containing a large number of inclined guide pillars, sliding blocks, pressing blocks, etc., not only the manufacturing cost is high, but also the moving parts are easy to wear in the long-term high-strength working environment, resulting in precision decline, high failure rate and difficult maintenance. The latter can solve the demolding problem, but the core-making cost is high, the process is complicated, and the positioning accuracy and strength of the sand core are difficult to guarantee, which is easy to shift or break during pouring, affecting the quality of the final casting.

[0005] For example, the Chinese patent document with publication number CN113941691B discloses an automatic core-pulling casting mold, which comprises a fixed mold and a movable mold. The fixed mold is fixedly arranged and provided with a lower cavity. The movable mold is provided with an upper cavity. A plurality of sliding core blocks and a plurality of turnover core blocks are mounted on the side of the fixed mold. A pair of core rod components are installed on the fixed mold and penetrate the lower cavity. The required sand core is formed through the cooperation of the lower cavity, the upper cavity, the sliding core blocks, the turnover core blocks, and the core rod components. When the sand core is formed, the core rod components are driven to separate from the sand core through cooperation with a driving assembly installed on the movable mold. The sliding core blocks are adapted to separate from the sand core through horizontal movement under the drive of a hydraulic device. The sand core is separated from the lower cavity through upward movement under the drive of an ejecting mechanism, thereby driving the turnover core blocks to separate from the sand core through turnover.

[0006] In the related art, a casting mold often needs to use a large number of core blocks and core rods when making a sand core. The core pulling of the core blocks and the core rods is basically driven by a hydraulic device. However, for complex parts, such as an engine block of an automobile or a turbocharger shell, the structure is complex and the overall size is large. Therefore, when using a conventional core pulling method to pull the core, the axial stroke of the hydraulic device is long or interference occurs between multiple hydraulic devices, which is inconvenient to use. SUMMARY

[0007] The present application provides a core-pulling casting mold, which aims to solve the problem of inconvenient removal of complex parts from the casting mold in the related art.

[0008] The core-pulling casting mold provided by the present application adopts the following technical solution:

[0009] A core-pulling casting mold, comprising a fixed mold and a movable mold, the movable mold and the fixed mold are close to each other to close the mold or far away from each other to open the mold; the fixed mold and the movable mold form a first cavity in the closed mold state; the fixed mold comprises a first fixed part and a second fixed part; a second cavity is formed between the first fixed part and the second fixed part; a communication part is formed on the first fixed part, the communication part is used to communicate the first cavity and the second cavity, a clearance hole is formed on the first fixed part, the clearance hole penetrates the communication part, the cross section of the communication part is enlarged at the clearance hole, so as to facilitate the removal of the turbine shell mold in the second cavity, a first forming mold is detachably installed in the clearance hole; the first forming mold is used to fill the clearance hole and reduce the cross section of the communication part to a preset casting size.

[0010] By adopting the technical scheme, since the two ends of the turbine shell are large in cross section and the middle part is small in cross section, the cross section of the second cavity between the first fixed part and the second fixed part is large, the cross section of the first cavity between the first fixed part and the movable die is also large, but the cross section of the middle part is small, in order to facilitate taking out the turbine shell die in the second cavity, the communicating part is provided with a clearance hole, the cross section of the clearance hole is larger than that of the second cavity, and the first forming die is arranged in the clearance hole, the first forming die is detachably connected in the clearance hole, after pouring is completed, the first forming die and the die in the second cavity are directly taken off from the first fixed part, the core pulling from the movable die and the fixed die is facilitated, after the core pulling is completed, the first forming die is installed into the clearance hole, pouring is carried out subsequently, and then in the use process, the traditional core pulling mode is replaced, the whole core pulling device is simpler, the manufacturing cost is reduced, and thus the complicated part body is conveniently taken off from the fixed die and the movable die.

[0011] Optionally, the first forming die comprises a first die, a second die, a third die and a fourth die, and the first die, the second die, the third die and the fourth die jointly enclose the cavity of the communicating part.

[0012] By adopting the technical scheme, the split design makes the communicating part forming and demolding more flexible, the multiple die structures ensure that the combined force is uniform, the interference fit prevents the sand from leaking during pouring, the material flow is optimized while the structural strength is ensured, the actual measurement shows that the sand filling speed is improved by 40% under the ratio, and the workpiece is not easy to be stuck during demolding, and the first die, the second die, the third die and the fourth die are also convenient for local replacement of worn parts, thereby reducing the maintenance cost.

[0013] Optionally, the second fixed part is provided with a second forming die; the second forming die comprises two left turbine dies and right turbine dies that can move relative to each other, and the left turbine dies and the right turbine dies form a turbine die chamber when they move close to each other; the first fixed part is further provided with a first control cylinder and a second control cylinder, a piston rod of the first control cylinder is connected with the left turbine dies, and a piston rod of the second control cylinder is connected with the right turbine dies, for driving the opening and closing movement of the left turbine dies and the right turbine dies respectively.

[0014] By adopting the technical scheme, the split turbine die driven by two independent cylinders realizes accurate forming and automatic core pulling of the turbine structure, the clamping pressure can reach 8MPa to ensure that the turbine blade profile is clear, the synchronous control of the cylinders makes the opening and closing accuracy of the die reach ±0.05mm, the cavity damage caused by traditional manual demolding is avoided, and the surface roughness of the turbine part can reach Ra3.2μm.

[0015] Optionally, the first fixing part is provided with a mounting hole, and a shaking assembly is arranged in the mounting hole.

[0016] By adopting the above technical scheme, the eccentric vibration mechanism can improve the sand filling density by more than 15%, the vibration frequency can be adjusted at 20-50 Hz, the air holes larger than 2 mm can be effectively eliminated, the double-position design can ensure the compaction effect and avoid interference demolding, and the subsequent exhaust system can make the porosity of the casting less than 0.5%.

[0017] Optionally, a plugging rod is slidably connected in the mounting hole, the outer diameter of the plugging rod abuts against the inner wall of the mounting hole, the plugging rod is used for plugging the mounting hole, the plugging rod is sleeved on the flexible connecting rod, and the flexible connecting rod can slide and rotate on the plugging rod at the same time.

[0018] By adopting the above technical scheme, the porous plugging structure can realize gas exhaust (exhaust efficiency > 90%) during sand injection, the pore diameter of 0.3-0.5 mm can block sand and ventilate, the sliding sealing design can reduce the residual amount of the release agent by 80%, and the cleaning cycle can be prolonged by 3 times.

[0019] Optionally, the first fixing part is provided with a release agent discharge port, the release agent discharge port is coaxially arranged with the mounting hole, the diameter of the release agent discharge port is greater than that of the mounting hole, when the plugging rod is in the release agent discharge port, there is a gap between the surface of the plugging rod and the inner wall of the release agent discharge port, and the release agent is discharged through the gap between the surface of the plugging rod and the inner wall of the release agent discharge port.

[0020] By adopting the above technical scheme, the stepped discharge channel can realize rapid discharge (discharge within 3 seconds) of the release agent, the cylinder drive ensures that the contact pressure of the sealing surface is uniform, and the leakage amount is less than 0.1 ml / min. The structure can shorten the mold preparation time to 30 seconds / time, and the efficiency is improved by 5 times compared with the traditional manual cleaning.

[0021] Optionally, the fixed mold and the movable mold are provided with a feeding gap, and the feeding gap forms a feeding port for injecting the sand when the fixed mold and the movable mold are closed.

[0022] By adopting the above technical scheme, after the molds are closed, the feeding port is formed, then the sand is injected into the first cavity through the feeding port, and then the sand in the first cavity is made to enter the second cavity through the communication part by pressure, thereby realizing the sand injection into the first cavity and the second cavity.

[0023] Optionally, the second fixed part is also provided with a shaking assembly, and the shaking assembly on the second fixed part is used for vibrating the sand in the second cavity, so that the sand in the second cavity is more compact.

[0024] Optionally, a plurality of exhaust holes are formed on the plugging rod, and the exhaust holes are uniformly arranged in the circumferential direction of the plugging rod.

[0025] Optionally, the first fixed part is made of ZG270-500 cast steel, and the second fixed part is made of HT250 gray cast iron.

[0026] By adopting the above technical scheme, the cast steel main mold body bears a working temperature of 800 DEG C or above, and the thermal fatigue life reaches 100,000 times; the cast iron mounting part provides excellent damping (damping coefficient 0.02-0.03), reduces the equipment vibration noise by 15dB, and the material combination reduces the mold comprehensive cost by 25%.

[0027] In summary, the present application includes at least one of the following beneficial technical effects:

[0028] 1. After pouring is completed, the first forming mold and the mold in the second cavity are directly taken off from the first fixed part, which can facilitate the core pulling from the movable mold and the fixed mold, and after the core pulling is completed, the first forming mold is installed into the accommodation hole for subsequent pouring, and then in the use process, the traditional core pulling mode is replaced, so that the entire core pulling device is simpler, the manufacturing cost is reduced, and the complex part body is conveniently taken off from the fixed mold and the movable mold.

[0029] 2. The workpiece is not easy to be stuck during demolding, and the first mold, the second mold, the third mold and the fourth mold also facilitate local replacement of worn parts, thereby reducing the maintenance cost. DETAILED DESCRIPTION

[0030] Figure 1 is a mold closing state schematic diagram of an embodiment of the present application.

[0031] Figure 2 is an overall structure explosion schematic diagram of an embodiment of the present application.

[0032] Figure 3 is a schematic diagram of a turbine casing mold in the first cavity of an embodiment of the present application.

[0033] Figure 4 is a schematic diagram of a turbine casing mold disengaging from the first cavity of an embodiment of the present application.

[0034] Figure 5 is a structure schematic diagram of a second forming mold of an embodiment of the present application.

[0035] Figure 6Figure 1 is a schematic diagram of a first forming die and a turbine housing die connected according to an embodiment of the present application.

[0036] Figure 7 Figure 2 is a schematic diagram of a structure of a first forming die according to an embodiment of the present application.

[0037] Figure 8 Figure 3 is a schematic diagram of a structure of a turbine housing die according to an embodiment of the present application.

[0038] Figure 9 Figure 4 is a schematic diagram of a structure of a second forming die and a first forming die according to an embodiment of the present application.

[0039] Figure 10 Figure 5 is a schematic diagram of a structure of a shaking assembly according to an embodiment of the present application.

[0040] Figure 11 Figure 6 is Figure 3 Figure 6 is an enlarged view of A in Figure 5.

[0041] Figure 12 Figure 7 is Figure 4 Figure 7 is an enlarged view of B in Figure 6.

[0042] Figure 13 Figure 8 is a schematic diagram of a structure of an exhaust hole according to an embodiment of the present application.

[0043] Reference signs: 01, turbine housing die; 1, fixed die; 11, first fixed part; 12, second fixed part; 2, movable die; 21, first cavity; 22, second cavity; 23, feeding opening; 24, communication part; 3, first forming die; 31, first die; 32, second die; 33, third die; 34, fourth die; 4, second forming die; 41, left turbine die; 42, right turbine die; 43, first control cylinder; 44, second control cylinder; 5, shaking assembly; 51, flexible connecting rod; 52, shaking rod; 6, mounting hole; 61, plugging rod; 62, exhaust hole; 63, release agent discharge port. DETAILED DESCRIPTION

[0044] The following Figures 1-13 The present application is further described in detail.

[0045] The core-pulling casting mold according to an embodiment of the present application comprises a fixed die 1 and a movable die 2, and cavities are arranged on the fixed die 1 and the movable die 2. When the fixed die 1 and the movable die 2 are combined together, the cavities on the fixed die 1 and the movable die 2 form a first cavity 21 for placing a mold. Feeding notches are arranged on the fixed die 1 and the movable die 2. When the fixed die 1 and the movable die 2 are combined together, the feeding notches form a circular feeding opening 23. Therefore, through a feeding device, molding sand can be added into the cavity between the fixed die 1 and the movable die 2, so that the molding sand can be conveniently injected into the first cavity 21.

[0046] The fixed mold 1 and the moving mold 2 are two main parts of the mold, and in operation, the moving mold 2 reciprocates linearly relative to the fixed mold 1 on a guide rail (not shown in the figure), and the moving mold 2 and the fixed mold 1 are both provided with drive cylinders, and by supplying or discharging compressed air to the drive cylinders through a control system, the moving mold 2 and the fixed mold 1 can be driven to realize synchronous and smooth approaching (mold closing) or moving away (mold opening), and then when the moving mold 2 and the fixed mold 1 move away from each other, the workers can take out the formed turbine shell mold 01 from the fixed mold 1, and when the drive cylinders drive the fixed mold 1 to move close to the moving mold 2, the sand can be injected into the first cavity 21 through the feeding assembly, and after a series of operations such as heating, the injected sand can be solidified to serve as a mold for casting a turbine shell.

[0047] Specifically, in the mold closing state, the fixed mold 1 and the moving mold 2 are precisely fitted, and the fixed mold 1 and the moving mold 2 enclose a first cavity 21 for containing and solidifying sand, and when the mold is closed, the feeding gap on the fixed mold 1 and the moving mold 2 is accurately aligned to form a complete circular feeding port 23, which is connected with an external feeding device (for example, a sand bucket with a valve). During production, the valve is opened, and the matched coated sand or resin sand is quickly injected into each cavity inside the mold through the feeding port 23 under the action of gravity or air pressure.

[0048] The fixed mold 1 includes a first fixed part 11 and a second fixed part 12, and the first fixed part 11 and the second fixed part 12 are tightly connected by a plurality of high-strength bolts; in order to ensure the accurate relative position between the two and prevent misalignment in long-term operation, at least two precision positioning pins are also provided, and the diameter tolerance of the pins is extremely small (for example, reaching 0.02 mm), and the pins form a precise transition or interference fit with the pin holes on the first fixed part 11 and the second fixed part 12. The combination of “bolt fastening + precision pin positioning” ensures the rigidity and extremely high repeat positioning accuracy of the fixed mold 1 as a whole, and the repeat positioning accuracy can be stabilized within 0.1 mm after repeated tests.

[0049] The first fixed part 11 is located between the second fixed part 12 and the moving mold 2, and is a component for forming the main cavity and bearing the main mold locking force, and the material thereof is selected from ZG270-500 cast steel. Compared with cast iron, cast steel has higher strength, plasticity and toughness, and can better withstand thermal stress and mechanical impact during casting.

[0050] The second fixed part 12 is located at the outermost side of the mold (away from the moving mold 2), and mainly serves to connect and install the large end of the turbine shell mold 01, and in this embodiment, the material thereof is selected from HT250 gray cast iron, which has excellent casting performance, machining performance and shock absorption.

[0051] The first fixed part 11 and the second fixed part 12 can be driven to move simultaneously; when producing the turbine housing, the turbine housing has large cross sections at both ends and a small cross section at the middle connecting part 24, at this time, a closed cavity, defined as the second cavity 22, is naturally formed between the mating surfaces of the first fixed part 11 and the second fixed part 12, and the cavity is used for pouring one end of the turbine housing (for example, the end connected with the engine exhaust manifold).

[0052] In order to connect the first cavity 21 and the second cavity 22 to form a complete turbine housing mold 01, a through connecting part 24 is formed on the first fixed part 11, and the connecting part 24 is used for pouring the smallest cross section connecting part 24 in the middle of the turbine housing; in this embodiment, the connecting part 24 is used for connecting the first cavity 21 and the second cavity 22, and the first cavity 21 and the second cavity 22 are used for casting both ends of the turbine housing, and the connecting part 24 is used for pouring the middle position of the turbine housing mold 01.

[0053] On the first fixed part 11, a relief hole with a cross section much larger than the actual required cross section of the connecting part 24 is processed around the position of the connecting part 24; in this embodiment, the cross section of the relief hole is larger than the maximum cross section of the end of the turbine housing mold 01; then the formed turbine housing mold 01 can be easily taken out of the fixed mold 1; in this embodiment, under the action of the relief hole, the cross section of the connecting part 24 is larger than the cross section of the end of the turbine housing mold 01, then when the poured mold is taken out, the mold in the second cavity 22 passes through the connecting part 24, and finally passes through the first cavity 21, so that the poured turbine housing mold 01 can be easily taken out of the fixed mold 1.

[0054] In order to restore the required small cross section of the connecting part 24 during pouring, the first forming mold 3 is arranged in the relief hole, and then the first forming mold 3 is detachably connected to the fixed mold 1; since the first forming mold 3 is accurately installed in the relief hole, it plays the role of filling the excess space and forming; when the formed turbine housing mold 01 is taken out, the first forming mold 3 is also taken out directly, and finally it is installed in the relief hole.

[0055] The first forming die 3 comprises a first die 31, a second die 32, a third die 33 and a fourth die 34, the first die 31, the second die 32, the third die 33 and the fourth die 34 surround the communication part 24, the cross section of the surrounded communication part 24 is smaller than the cross section of the end part of the turbine shell die 01, then the cross section of the communication part 24 after pouring is also smaller than the cross section of the end part of the turbine shell die 01, the first die 31, the second die 32, the third die 33 and the fourth die 34 are fan-shaped or wedge-shaped, when they are combined together, the outer contour thereof is precisely matched with the inner wall of the accommodation hole, and can be stably clamped therein, and the central passage surrounded by the inner portions thereof has the cross section size and shape which are exactly the final size required by the communication part 24 of the turbine shell die 01.

[0056] When the poured turbine shell die 01 is taken out, the poured turbine shell die 01 and the first die 31, the second die 32, the third die 33 and the fourth die 34 are directly taken out, after the turbine shell die 01 and the first die 31, the second die 32, the third die 33 and the fourth die 34 are taken out, the first die 31, the second die 32, the third die 33 and the fourth die 34 need to be clamped in the accommodation hole, the movable die 2 and the fixed die 1 are moved close to each other, and finally the molding sand can be added into the cavity between the fixed die 1 and the movable die 2 by the feeding device for subsequent pouring.

[0057] The second forming die 4 is arranged in the second fixed part 12, the second forming die 4 comprises a left turbine die 41 and a right turbine die 42, the first control cylinder 43 and the second control cylinder 44 are arranged on the fixed die 1, the piston rod of the first control cylinder 43 is fixedly connected with the left turbine die 41, the piston rod of the second control cylinder 44 is fixedly connected with the right turbine die 42, the first control cylinder 43 and the second control cylinder 44 drive the left turbine die 41 and the right turbine die 42 to move close to or away from each other, when the left turbine die 41 and the right turbine die 42 move close to each other, a turbine die cavity is formed, and a circular turbine body is poured in the pouring process. The left turbine die 41 and the right turbine die 42 are provided with a connecting groove, when the left turbine die 41 and the right turbine die 42 abut, a connecting hole for connecting the turbine die cavity and the communication part 24 is formed.

[0058] After the pouring is completed, the first control air cylinder 43 and the second control air cylinder 44 drive the left turbine mold 41 and the right turbine mold 42 to move away from each other, respectively. During the moving away of the left turbine mold 41 and the right turbine mold 42, the turbine casing mold 01 after pouring is exposed, and then the turbine casing mold 01 after pouring and the first mold 31, the second mold 32, the third mold 33 and the fourth mold 34 sleeved on the turbine casing mold 01 are taken out from the first cavity 21. Finally, the first mold 31, the second mold 32, the third mold 33 and the fourth mold 34 are taken off from the formed turbine casing mold 01, and then the first mold 31, the second mold 32, the third mold 33 and the fourth mold 34 are clamped in the connecting hole, thereby facilitating the pouring of the subsequent turbine casing mold 01.

[0059] During the sand injection process, the molding sand enters the first cavity 21 through the feeding port 23, and then enters the second cavity 22 through the communication part 24 surrounded by the first mold 31, the second mold 32, the third mold 33 and the fourth mold 34. Due to the small cross section of the communication part 24, gaps are easily formed between the molding sand entering the second cavity 22, which causes bubbles in the turbine casing mold 01 after casting, affecting the quality of the turbine casing mold 01. At this time, the first fixed part 11 and the second fixed part 12 are both provided with a shaking assembly 5, which generates vibration during operation. The vibration makes the molding sand in the first cavity 21 and the second cavity 22 more compact, reducing the occurrence of dead angles.

[0060] The first fixed part 11 is provided with a mounting hole 6, and the shaking assembly 5 is arranged in the mounting hole 6. The shaking assembly 5 includes a rotating flexible connecting rod 51, a shaking rod 52 fixed on the flexible connecting rod 51, a shaking cylinder arranged on the first fixed part 11 and a shaking motor fixed on the shaking cylinder. The output shaft of the shaking motor is fixedly connected with one end of the flexible connecting rod 51. The flexible connecting rod 51 is driven to rotate by the shaking motor, and the shaking rod 52 is driven to rotate by the flexible connecting rod 51. Since the shaking rod 52 is fixedly connected with the output shaft of the shaking motor through the flexible connecting rod 51, and under the action of the flexible connecting rod 51, the shaking rod 52 will eccentrically rotate (the axis of the shaking rod 52 is not on the same straight line as the axis of the shaking motor) during the rotation of the shaking rod 52. Due to the eccentric rotation of the shaking rod 52, the molding sand in the first cavity 21 can be vibrated, making the molding sand in the first cavity 21 more compact. After the shaking is completed, the shaking motor is moved in the opposite direction by the shaking cylinder, the shaking motor drives the flexible connecting rod 51 and the shaking rod 52 to move in the opposite direction, and finally the shaking rod 52 is separated from the first cavity 21. Since the shaking motor and the shaking cylinder are prior art, the specific working principle of the shaking motor and the shaking cylinder is not described again in this embodiment.

[0061] A plugging rod 61 is slidably connected in the mounting hole 6, the outer diameter of the plugging rod 61 abuts against the inner wall of the mounting hole 6, the plugging rod 61 is sleeved on the flexible connecting rod 51, the flexible connecting rod 51 can slide and rotate on the plugging rod 61 at the same time, a plurality of exhaust holes 62 are formed on the plugging rod 61, the exhaust holes 62 are uniformly arranged along the circumference of the plugging rod 61, the diameter of the exhaust holes 62 is small, the sand in the first cavity 21 cannot pass through, when the sand is injected into the first cavity 21 through the feeding port 23, the gas in the first cavity 21 and the second cavity 22 can be discharged through the exhaust holes 62, and the residual gas in the first cavity 21 and the second cavity 22 can be reduced during the sand injection process.

[0062] In order to facilitate the removal of the turbine shell mold 01 in the first cavity 21, the second cavity 22 and the communication part 24, the mold release agent needs to be injected into the first cavity 21, the second cavity 22 and the communication part 24 before each sand injection, in order to reduce the residual mold release agent, a mold release agent discharge port 63 is arranged on the first fixed part 11, the mold release agent discharge port 63 is coaxially arranged with the mounting hole 6, the diameter of the mold release agent discharge port 63 is larger than the diameter of the mounting hole 6, when the mold release agent in the first cavity 21, the second cavity 22 and the communication part 24 needs to be discharged, the plugging rod 61 is pulled, so that the plugging rod 61 is no longer in the mounting hole 6, at this time, there is a gap between the surface of the plugging rod 61 and the inner wall of the mold release agent discharge port 63, the mold release agent can pass through the gap between the surface of the plugging rod 61 and the inner wall of the mold release agent discharge port 63 and be discharged, when the sand is injected, the plugging rod 61 is pushed, so that the plugging rod 61 is in the mounting hole 6, at this time, the outer wall of the plugging rod 61 abuts against the inner wall of the mounting hole 6, the mounting hole 6 is plugged, the air in the first cavity 21 and the second cavity 22 is discharged through the exhaust holes 62, in the embodiment, in order to facilitate the movement of the plugging rod 61, a shaking cylinder (not shown in the figure) is arranged on the first fixed part 11, the output shaft of the shaking cylinder is fixed on the plugging rod 61, the plugging rod 61 is reciprocally moved by the shaking cylinder.

[0063] The implementation principle of the core-pulling casting mold in the embodiment of the application is as follows: the first mold 31, the second mold 32, the third mold 33 and the fourth mold 34 are correctly combined, and are clamped and installed from the outside of the fixed mold 1 into the displacement hole of the first fixed part 11, the first control cylinder 43 and the second control cylinder 44 are controlled, so that the left turbine mold 41 and the right turbine mold 42 are closed in the second fixed part 12, a turbine mold cavity to be poured is formed, the driving cylinder is started, the movable mold 2 is driven to move at a high speed towards the fixed mold 1, is slowed down when about to contact, and finally is slowly and smoothly attached to the fixed mold 1 (specifically, the first fixed part 11).

[0064] The first cavity 21, the second cavity 22 and the communication part 24 surrounded by the first forming die 3 jointly form a complete and closed turbine shell shape die cavity, and the top feed port 23 is also formed. The feeding device is started to inject a certain amount of molding sand into the die cavity through the feed port 23, and the molding sand fills all the cavities under the action of gravity or air pressure. According to the type of the molding sand used, heating or blowing of a curing agent gas is carried out to make the molding sand quickly solidify in the die cavity to form a turbine shell die 01 with sufficient strength.

[0065] After solidification, the first control cylinder 43 and the second control cylinder 44 are first started to drive the left turbine die 41 and the right turbine die 42 to retreat to the two sides and move away from each other, which completes the extraction of the turbine flow passage inner core and releases the internal constraint. The driving cylinder works in reverse to drive the moving die 2 to synchronously and stably retreat outward with the fixed die 1, thereby completing the mold opening action of the main mold.

[0066] After the mold is opened, the formed turbine shell die 01 remains on the side of the fixed die 1. Since the clearance hole has a channel cross section larger than the cross section of the sand mold at the end of the turbine shell die 01, a worker or an automatic mechanical hand can directly take out the entire formed turbine shell die 01 together with the first die 31, the second die 32, the third die 33 and the fourth die 34 as a whole from the fixed die 1 in the direction of the first cavity 21, and place the extracted "sand mold + insert" combination to a designated station, and then sequentially take out the first die 31, the second die 32, the third die 33 and the fourth die 34 from the outside of the sand mold communication part 24.

[0067] The removed first die 31, the second die 32, the third die 33 and the fourth die 34 are cleaned, and then reassembled and clamped back into the clearance hole of the first fixed part 11. At the same time, the left turbine die 41 and the right turbine die 42 inside are reset and closed under control, and the entire mold returns to the initial preparation state, waiting for the start of the next production cycle.

[0068] The above are preferred embodiments of the present application, which do not limit the protection scope of the present application. Therefore, any equivalent changes made on the basis of the structure, shape and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A core-pulling casting mold comprising a fixed mold and a movable mold, characterized by: The movable mold and the fixed mold are close to each other to close the mold or far away from each other to open the mold; the fixed mold and the movable mold enclose a first cavity in the closed mold state; the fixed mold comprises a first fixed part and a second fixed part; a second cavity is formed between the first fixed part and the second fixed part; a communication part is provided on the first fixed part, the communication part is used for communicating the first cavity and the second cavity, a clearance hole is provided on the first fixed part, the clearance hole penetrates the communication part, the cross section of the communication part is enlarged at the clearance hole, so as to facilitate taking out the turbine shell mold in the second cavity, and the first forming mold is detachably installed in the clearance hole; The first forming mold is used for filling the clearance hole and reducing the cross section of the communication part to a preset casting size; The first forming mold comprises a first mold, a second mold, a third mold and a fourth mold, the first mold, the second mold, the third mold and the fourth mold jointly enclose a cavity of the communication part, the first mold, the second mold, the third mold and the fourth mold are fan-shaped or wedge-shaped, and when they are combined together, the outer contour thereof is precisely matched with the inner wall of the clearance hole and can be stably clamped therein; And the cross section size and shape of the central passage jointly enclosed by the inner part thereof are exactly the final size required by the communication part of the turbine shell mold; the first forming mold and the mold in the second cavity are directly taken off from the first fixed part, the core is drawn from the movable mold and the fixed mold, after the core drawing is completed, the first forming mold is installed into the clearance hole, and then pouring is carried out; The first fixed part is provided with a mounting hole, a shaking assembly is arranged in the mounting hole, the shaking assembly comprises a flexible connecting rod, a shaking rod and a shaking motor, the shaking motor drives the flexible connecting rod to drive the shaking rod to eccentrically rotate, a shaking cylinder is arranged on the first fixed part, a piston rod of the shaking cylinder is connected with the shaking motor, and the shaking cylinder is used for driving the shaking motor to reciprocate along the horizontal direction; A plugging rod is slidably connected in the mounting hole, the outer diameter of the plugging rod abuts against the inner wall of the mounting hole, the plugging rod is used for plugging the mounting hole, the plugging rod is sleeved on the flexible connecting rod, and the flexible connecting rod simultaneously slides and rotates on the plugging rod; a plurality of exhaust holes are uniformly arranged on the plugging rod in the circumferential direction of the plugging rod; The first fixed part is provided with a release agent discharge port, the release agent discharge port is coaxially arranged with the mounting hole, the diameter of the release agent discharge port is larger than that of the mounting hole, when the plugging rod is in the release agent discharge port, there is a gap between the surface of the plugging rod and the inner wall of the release agent discharge port, and the release agent is discharged through the gap between the surface of the plugging rod and the inner wall of the release agent discharge port.

2. A core-drawing mold according to claim 1, characterized in that: The second fixed part is provided with a second forming mold; the second forming mold comprises two left turbine molds and right turbine molds which can move relative to each other, and the left turbine mold and the right turbine mold form a turbine mold chamber when they are close to each other; the first fixed part is further provided with a first control cylinder and a second control cylinder, a piston rod of the first control cylinder is connected with the left turbine mold, a piston rod of the second control cylinder is connected with the right turbine mold, and the first control cylinder and the second control cylinder are used for driving the opening and closing movement of the left turbine mold and the right turbine mold respectively.

3. A core-drawing mold according to claim 1, characterized in that: The fixed mold and the movable mold are provided with a feeding gap, and the fixed mold and the movable mold jointly form a feeding port for injecting the sand when the fixed mold and the movable mold are closed.

4. A core-drawing mold according to claim 2, wherein: The second fixed part is also provided with a shaking assembly, which is used for vibrating the sand in the second cavity, so that the sand in the second cavity is more compact.

5. A core-drawing mold according to claim 1, characterized by: The first fixed part is made of ZG270-500 cast steel, and the second fixed part is made of HT250 gray cast iron.

Images