Stator pressing ring casting mold

Abstract

The utility model discloses a stator pressing ring casting mold which comprises an upper mold, a lower mold and core boxes, and the core boxes comprise a core box I used for forming a center mud core and a core box II used for forming a precoated sand mud core; the upper mold comprises an upper bottom plate, a riser mold arranged on the upper bottom plate and a plurality of precoated sand mud core molds distributed corresponding to all kidney-shaped inner cavities in the stator pressing ring; the lower mold comprises a lower bottom plate and a convex mold which is arranged on the lower bottom plate and is used for forming a central mud core and a precoated sand mud core placing groove; the upper mold is used for forming a cover box, the lower mold is used for forming a sand core, and the sand core and the cover box are closed to form a stator pressing ring casting cavity. A precoated sand forming mold is designed to replace a resin sand forming mold, a kidney-shaped inner cavity is formed through a precoated sand mud core, the crack defect and the internal inclusion and burnt-on sand problems of a product are restrained, the surface quality of the product is improved, the internal compactness of the product is high, the size of the precoated sand mud core is stable, and it can be guaranteed that the size of the kidney-shaped inner cavity of the stator pressing ring meets the drawing requirement.

Description

Technical Field

[0001] The utility model relates to the technical field of parts casting, in particular to a stator pressure ring casting mould. Background Art

[0002] The stator pressing ring is an integral annular component, which is used to press the stator punching to prevent it from bouncing. Figure 1 and attached Figure 2 As shown, a circle of waist-shaped inner cavities for weight reduction is arranged around the stator pressing ring, and the width of a single waist-shaped inner cavity along the radial direction of the stator pressing ring is very small, generally only a dozen millimeters wide. For example, in the patent application with publication number CN112713673A, a circle of waist-shaped inner cavities is arranged around the stator pressing ring.

[0003] There are two traditional methods for making the stator pressing ring, one is resin sand casting and the other is cavity casting. Both molding methods have some defects, as follows:

[0004] Resin sand molding: For the waist-shaped inner cavity, resin sand molding is difficult. After molding, the clay core has no strength and there will be uncontrollable deformation. It is also easy to break and deform during the subsequent brushing and baking process. That is, if the waist-shaped inner cavity is directly cast using resin sand casting, the size is uncontrollable, which will lead to uneven wall thickness of the stator pressure ring, and the final product does not meet the requirements of the drawing and cannot be used.

[0005] In addition, the surface finish of the inner cavity of the waist-shaped molded part made of resin sand is poor, and defects such as sand sticking and sand holes are prone to occur. The inner cavity of the waist-shaped mold has extremely small space, which makes cleaning and rework extremely difficult. The product qualification rate is extremely low, and problems are prone to occur during the operation of the product. Due to the effect of cross stress, defects expand and extend to the surface to form cracks, causing the casting to crack, and scrapping occurs from time to time.

[0006] Cavity casting: The inner cavity of the stator pressure ring is cast solid, and then a waist-shaped inner cavity is processed. This solution has extremely high manufacturing and processing costs, low product yield, and long production cycle.

[0007] The patent with announcement number CN219169551U discloses a casting mold for a cast steel stator pressure ring, which includes an upper mold and a lower mold that cooperate with each other, the inner side of the upper mold has an upper mold core, the inner side of the lower mold has a lower mold core that matches the upper mold core, and the upper mold core and the lower mold core are both provided with multiple ingates that penetrate the upper mold; the outer side of the upper mold is provided with multiple riser mounting holes arranged along the circumferential direction, and multiple necking riser mounting holes are arranged around the riser mounting holes at intervals, and the diameter of the necking riser mounting holes is larger than the diameter of the riser mounting holes. The utility model changes the structure of the traditional core casting mold, so that each position of the prepared core can be uniformly and simultaneously formed, so that a high-quality stator pressure ring casting can be finally prepared through the core.

[0008] The main starting point of the above-mentioned casting mold is to prevent the core from shrinkage and deformation, and to improve the molding quality of the core by greatly compensating for the molding of the core during casting; it does not involve the molding of the oval inner cavity on the stator pressure ring. Summary of the invention

[0009] The technical problem to be solved by the utility model is to provide a stator pressing ring casting mold for waist-shaped inner cavity molding and size control in view of the defects of the prior art.

[0010] The purpose of the utility model is achieved through the following technical solutions:

[0011] A stator pressing ring casting mold, the casting mold is a coated sand casting mold, comprising a mold upper mold, a mold lower mold and a core box, the core box comprising a core box 1 for forming a central clay core and a core box 2 for forming a coated sand clay core; the mold upper mold comprises an upper bottom plate, a riser mold arranged on the upper bottom plate and a plurality of coated sand clay core molds corresponding to the respective oval-shaped inner cavities on the stator pressing ring; the mold lower mold comprises a lower bottom plate, a convex mold arranged on the lower bottom plate for forming a groove for placing the central clay core and the coated sand clay core; the mold upper mold is used to form a cover box, the mold lower mold is used to form a sand core, and the sand core and the cover box are molded together to form a stator pressing ring casting cavity.

[0012] Furthermore, there are multiple riser dies which are evenly arranged.

[0013] Furthermore, a riser mold is provided between adjacent coated sand-cement core molds.

[0014] Furthermore, the riser formed by the riser die is a heat-generating dark riser.

[0015] Furthermore, at least one positioning protrusion is circumferentially provided on the upper surface of the male mold of the lower mold, and a groove matching the positioning protrusion is provided on the core box 2.

[0016] Furthermore, at least three central clay core positioning convex parts are provided on the upper surface of the male mold of the lower mold of the mold near the center, and grooves adapted to the central clay core positioning convex parts are provided on the core box.

[0017] Furthermore, a sand core positioning pin is provided on the lower base plate, and the sand core positioning pin is arranged at a position away from the punch, and a positioning groove which is adapted to the position and structure of the sand core positioning pin is provided on the upper base plate.

[0018] Furthermore, a convex block 1 is provided on the lower base plate, and the convex block 1 is used to form a hollow portion on the sand core to reduce the amount of molding sand.

[0019] Furthermore, a second convex block is provided on the upper base plate, and the second convex block is used to form a hollow portion on the cover box to reduce the amount of molding sand.

[0020] Furthermore, the number of the convex molds arranged on the lower base plate is two or more.

[0021] Compared with the prior art, the utility model has the following beneficial effects:

[0022] A coated sand molding mold is designed to replace the traditional resin sand molding mold. The waist-shaped inner cavity of the stator pressure ring is cast by using a coated sand clay core, which suppresses the crack defects, internal inclusions, sand sticking and other problems of the product to the maximum extent, improves the surface quality of the product, and the internal density of the product is high, which is not easy to crack during subsequent operation, thereby increasing the service life of the stator pressure ring. At the same time, the coated sand clay core has stable size, which can ensure that the size of the waist-shaped inner cavity of the stator pressure ring meets the requirements of the drawing, and the product qualification rate is guaranteed.

[0023] The coated sand-cement core is used to cast the waist-shaped inner cavity in one step, which greatly reduces the product cost and production cycle and improves the production efficiency of the stator pressing ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic structural diagram of the stator pressure ring described in Example 1;

[0025] Figure 2 for Figure 1 Cross-section of the middle stator pressure ring;

[0026] Figure 3 It is a three-dimensional structural diagram of the upper mold of the casting mold described in Example 1;

[0027] Figure 4 It is a three-dimensional structural diagram of the lower mold of the casting mold described in Example 1;

[0028] Figure 5 It is a three-dimensional structural diagram of the core box 1 of the casting mold described in Example 1;

[0029] Figure 6 To adopt Figure 3 A three-dimensional structural diagram of a cover box formed by a mold shown in FIG.

[0030] Figure 7 To adopt Figure 4 The three-dimensional structure diagram of the sand core formed by the lower mold of the mold shown (the central clay core and the coated sand clay core have been placed in the placement groove). DETAILED DESCRIPTION

[0031] In order to clearly illustrate the technical features of the present solution, the present technical solution is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0033] In addition, in the description of the present application, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "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 accompanying drawings, and are only for the convenience of describing the present application 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 on the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0034] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0035] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0036] Example 1

[0037] like Figure 1 and Figure 2 The stator pressing ring shown has 11 oval-shaped inner cavities A evenly distributed in the circumferential direction, and the width of these oval-shaped inner cavities along the radial direction of the stator pressing ring is very small, only about 15 mm wide. In order to solve the problems of oval-shaped inner cavity molding and size control of the stator pressing ring casting, and simultaneously reduce crack defects and sand sticking of the stator pressing ring casting, this embodiment provides a stator pressing ring casting mold for molding the oval-shaped inner cavity of the stator pressing ring in one step.

[0038] The casting mold is a coated sand casting mold, which includes: Figure 3 The mold shown in the figure, Figure 4 The mold lower mold and two core boxes shown in the figure include a core box 1 for forming a central clay core C and a core box 2 for forming a coated sand clay core D (the central clay core and the coated sand clay core are shown in FIG. Figure 7 As shown), the core box is as Figure 5 As shown, in order to save molding sand, a space-occupying columnar structure 11 is provided in the center of the core box 1, and a positioning structure 12 is also provided on the inner wall of the core box to prevent the central clay core from rotating during molding. The coated sand clay core D formed by the core box 2 is adapted to the waist-shaped inner cavity structure of the stator pressing ring, and the coated sand clay core is used to form the waist-shaped inner cavity contour shape; the central clay core C is used to form the central hole B of the stator pressing ring.

[0039] Figure 3 The upper mold of the middle mold includes an upper bottom plate 21, a riser mold 22 arranged on the upper bottom plate, and 11 coated sand and cement core molds 23 corresponding to the respective oval-shaped inner cavities on the stator pressure ring; Figure 4 The lower mold of the middle mold includes a lower bottom plate 31 and a convex mold 32 disposed on the lower bottom plate for forming a groove for placing the central clay core and the coated sand clay core. Figure 6 The cover box shown in the figure, the lower mold is used to form the following Figure 7 The sand core and coated sand cement core mold 23 shown are used to form a concave profile 41 on the cover box that matches the coated sand cement core; after the central cement core C and the coated sand cement core D are placed in the placement groove 51 of the sand core, the sand core and the cover box are molded together to form a stator pressure ring casting cavity.

[0040] In order to improve the internal density of the casting, the casting mold of this embodiment improves the scattered arrangement of the risers in the traditional casting by setting a riser mold 22 between every two adjacent coated sand and mud core molds 23, so that multiple risers 42 are evenly arranged during subsequent pouring, and the risers 42 formed by the riser mold are all heat-generating dark risers, which can fully compensate for the shrinkage of the casting product.

[0041] In order to further improve the production efficiency, multiple convex molds 32 can be set on the lower bottom plate 31, and the riser mold, the coated sand mud core mold and each convex mold on the upper mold of the mold are arranged one by one, so as to form multiple sand cores and cover boxes at one time, thereby improving the casting efficiency of the stator pressure ring. In the casting mold of this embodiment, there are two convex molds 32 on the lower bottom plate, and the sand core and cover box formed subsequently share a sprue as a flow channel for molten steel after the mold is closed. After the molten steel is poured into the sprue, it flows into the casting cavity through the inner runner 6 connected to the casting cavity; the sprue is equipped with a gate nest to buffer the impact force of the molten steel during pouring.

[0042] In addition, a sand core locating pin 33 is also provided on the lower base plate 31. The sand core locating pin is set at a position away from the punch. The lower base plate 31 is generally rectangular in shape. The sand core locating pin 33 is set at the corner position of the rectangular lower base plate. The upper base plate 21 is provided with a positioning groove 24 that is compatible with the position and structure of the sand core locating pin 33. The sand core locating pin 33 is used to locate the sand core and the cover box to prevent the misshape from causing dimensional deviation. In this embodiment, the number of sand core locating pins is three, and the shape structure of at least one of the three sand core locating pins is different from the shape structure of the others, for example, the shape of one sand core locating pin is cylindrical, and the shapes of the other two are rectangular; this three-point positioning method can prevent the sand core and the cover box from rotating or the wrong position after the box is closed. In addition, the sand core locating pins and the positioning grooves can also be interchangeably arranged on the upper base plate and the lower base plate, as long as the positioning effect is achieved.

[0043] like Figure 4 As shown, three positioning protrusions 34 are also provided on the circumference of the upper surface of the punch 32 of the lower mold of the mold, and grooves adapted to the positioning protrusions are provided on the core box 2. At this time, the outer periphery of the bottom of the molded coated sand cement core will have corresponding convex parts. After the sand core is formed by the lower mold of the mold, positioning grooves adapted to the three positioning protrusions will appear at the bottom of the placement groove 51 of the mold. These positioning grooves cooperate with the convex parts at the bottom of the coated sand cement core to prevent the coated sand cement core from rotating after it is lowered to the sand core placement groove, thereby avoiding the problem of inaccurate size after the core is lowered due to the rotation of the coated sand cement core.

[0044] The upper surface of the convex mold 32 of the lower mold is also provided with three central core positioning protrusions 35 near the center. Figure 5 The core box 1 shown is provided with a positioning groove 13 adapted to the central core positioning protrusion 35. The central core positioning protrusion is used to prevent the central core from rotating after being placed in the groove, so as to avoid inaccurate size after the core is placed.

[0045] Among the above-mentioned three positioning protrusions on the upper surface of the punch and the three central clay core positioning protrusions, at least one has an external structure different from the external structures of the other two. This difference design is used on the one hand to prevent mistakes, and on the other hand to ensure the size and prevent the inaccurate position of the lower core from causing errors in product shape and size.

[0046] Figure 3 and Figure 4 In the figure, the lower bottom plate 31 and the upper bottom plate 21 are respectively provided with a protrusion 1 36 and a protrusion 25. The protrusion 1 and the protrusion 2 are arranged at the blank positions on the edges of the corresponding bottom plates. The protrusion 1 is used to form a hollow portion on the sand core, and the protrusion 2 is used to form a hollow portion on the cover box. The hollow portion 7 can save sand and will not have any effect on the molding of the casting.

[0047] The coated sand casting mold of this embodiment subverts the traditional casting method of the stator pressure ring, utilizes the advantages of coated sand molding, and improves the surface quality of the stator pressure ring, especially by forming the oval-shaped inner cavity in one time through the coated sand clay core. The coated sand clay core has stable size, which can ensure that the size of the oval-shaped inner cavity of the stator pressure ring meets the requirements of the drawings, reduce the generation of original cracks in the casting, and the surface of the oval-shaped inner cavity is smooth, with very few casting defects. The internal quality of the casting is stable, so that cracks are not easy to occur during the subsequent operation of the casting. In addition, combined with the improvement of the riser, the thermal field of the casting is uniform, which ensures the consistency of the shrinkage of the casting. The internal density of the casting is high, the dimensional accuracy is high, and it is not easy to cause failures during operation, which can significantly improve the service life of the stator pressure ring.

[0048] Example 2

[0049] The difference between this embodiment and embodiment 1 is that there is only one punch on the lower bottom plate, and only one sand core box cover box is formed at a time.

[0050] Example 3

[0051] The difference between this embodiment and embodiment 1 is that there are four central clay core positioning protrusions arranged near the center on the upper surface of the punch.

[0052] Obviously, the above embodiments are merely examples for clearly illustrating the technical solution of the utility model, and are not intended to limit the implementation methods of the utility model. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the utility model should be included in the protection scope of the claims of the utility model.

Claims

1. A stator pressure ring casting mold, characterized in that: The casting mold is a coated sand casting mold, including a mold upper mold, a mold lower mold and a core box, the core box including core box one for molding a central clay core and core box two for molding a coated sand clay core; the mold upper mold includes an upper bottom plate, a riser mold arranged on the upper bottom plate and a plurality of coated sand clay core molds corresponding to the oval inner cavities on the stator pressure ring; the mold lower mold includes a lower bottom plate, a convex mold arranged on the lower bottom plate for molding a central clay core and a coating sand clay core placement groove; the mold upper mold is used to mold a cover box, the mold lower mold is used to mold a sand core, and the sand core and the cover box are molded together to form a stator pressure ring casting cavity.

2. The stator pressure ring casting mold according to claim 1, characterized in that: There are multiple riser dies which are evenly arranged.

3. The stator pressure ring casting mold according to claim 2, characterized in that: A riser mold is arranged between adjacent coated sand-cement core molds.

4. The stator pressure ring casting mold according to claim 1, characterized in that: The riser formed by the riser die is a heat-generating dark riser.

5. The stator pressure ring casting mold according to claim 1, characterized in that: At least one positioning protrusion is also provided on the circumference of the upper surface of the male mold of the lower mold, and a groove matching the positioning protrusion is provided on the core box 2.

6. The stator pressure ring casting mold according to claim 1, characterized in that: At least three central clay core positioning convex parts are also arranged near the center on the upper surface of the male mold of the lower mold of the mold, and grooves adapted to the central clay core positioning convex parts are arranged on the core box.

7. The stator pressure ring casting mold according to claim 1, characterized in that: The lower base plate is also provided with a sand core positioning pin, and the sand core positioning pin is arranged at a position away from the punch. The upper base plate is provided with a positioning groove that is adapted to the position and structure of the sand core positioning pin.

8. The stator pressure ring casting mold according to claim 1, characterized in that: The lower bottom plate is also provided with a convex block 1, and the convex block 1 is used to form a hollow portion on the sand core to reduce the amount of molding sand.

9. The stator pressure ring casting mold according to claim 1, characterized in that: The upper bottom plate is also provided with a second protrusion, which is used to form a hollow portion on the cover box to reduce the amount of molding sand.

10. The stator pressure ring casting mold according to claim 1, characterized in that: The number of the convex molds arranged on the lower base plate is two or more.

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