An oval dry-type transformer coil casting mold

Abstract

The utility model relates to transformer technical field, specifically disclose a long circle dry -type transformer coil casting mould, its structure includes outer mould and inner mould, and the inner mould sets up in the inside of outer mould, and the outer mould and inner mould top are equipped with cross compression plate, and bottom is equipped with bottom plate, and the cross compression plate four corners and center are equipped with the bottom plate of tight pressing screw rod connection, and the top of both is equipped with a plurality of encircling mountain card board; The upper surface of bottom plate has sealed soft rubber pad, and the soft rubber pad has outer snap ring and inner snap ring, and the outer mould is located in the inner side of outer snap ring, and the inner mould is located in the outer side of inner snap ring, and the outer mould is close to the overflow port of top side wall, and the bottom surface of bottom plate is equipped with a plurality of liftable pedestal symmetrically. The utility model discloses through cross compression plate and tight pressing screw rod cooperation, mountain card board spacing between inner mould of positioning outer mould, offset outer mould stress and resin pressure prevent outer arching;Sealed soft rubber pad can prevent resin leakage, finally guarantee coil thickness even, size precision and forming quality, satisfy the demand of power equipment to coil performance stability.

Description

Technical Field

[0001] This utility model relates to the field of transformer technology, specifically to an oblong dry transformer coil casting mold. Background Technology

[0002] Oval-shaped dry-type transformer coils are core conductive components of critical power equipment such as transformers and reactors in power systems. They are widely used in industrial power distribution and power transmission, and their structural integrity and insulation performance directly determine the operational stability and service life of the power equipment. In the production process of oval-shaped dry-type transformer coils, the casting mold is an indispensable tooling device. Its function is to fix the winding shape, limit the resin pouring range, and ensure that the coil, after molding, has a structure and performance that meets design standards. Therefore, the rationality of the casting mold design plays a decisive role in the coil production quality and efficiency.

[0003] Traditional oval dry-type transformer coil casting molds mainly consist of an outer mold, an inner mold, and a base plate. The outer mold is made of thin stainless steel sheet by bending. While this design meets the requirements of easy bending and convenient installation, it has significant drawbacks in practical use. Due to the inherent stress of the thin stainless steel sheet and the internal pressure generated during resin casting, the straight sections on both sides of the outer mold are prone to outward arching deformation. This results in uneven overall coil thickness, specifically, the thickness of the straight sections exceeds the design value, while the thickness of the curved sections is below the standard requirement. This defect not only affects the uniformity of coil thickness, coil appearance, and operational safety, but also threatens the operational safety of the coil and makes it difficult to meet the requirements of power equipment for coil dimensional accuracy and performance stability. Utility Model Content

[0004] To address the technical deficiencies in the background art, this utility model proposes an oblong dry-type transformer coil casting mold, which solves the aforementioned technical problems and meets practical needs. The specific technical solution is as follows: An oblong dry-type transformer coil casting mold includes an outer mold and an inner mold. The inner mold is disposed inside the outer mold. A cross-shaped pressure plate is provided at the top of the outer mold and the inner mold. A base plate is provided at the bottom of the outer mold and the inner mold. A clamping screw for connecting the base plate is provided at the four corners and the center of the cross-shaped pressure plate. A plurality of mountain-shaped clamping plates for fixing the distance between the outer mold and the inner mold are provided between the top of the outer mold and the inner mold. The mountain-shaped clamping plates are arranged around the top of the outer mold and the inner mold.

[0005] As a further technical solution of this utility model, the bottom plate and the surface of the cross pressure plate are both provided with positioning holes corresponding to the position of the clamping screw, and the two ends of the clamping screw are respectively provided in the positioning holes of the bottom plate and the cross pressure plate.

[0006] As a further technical solution of this utility model, the two ends of the clamping screw are provided with fastening nuts that are threadedly engaged with the ends of the clamping screw, and the fastening nuts are respectively provided on the lower surface of the base plate and the upper surface of the cross pressure plate.

[0007] As a further technical solution of this utility model, a sealing soft rubber gasket is provided on the upper surface of the base plate, and an outer retaining ring and an inner retaining ring are provided on the upper surface of the sealing soft rubber gasket, with the inner retaining ring disposed inside the outer retaining ring. As a further technical solution of this utility model, the outer mold is disposed inside the outer retaining ring and matches the cross-sectional shape of the outer mold, and the inner mold is disposed outside the inner retaining ring and matches the cross-sectional shape of the inner mold.

[0008] As a further technical solution of this utility model, an overflow port is provided through the side wall of the outer mold near the top.

[0009] As a further technical solution of this utility model, the surface of the mountain-shaped card plate is symmetrically provided with mold slots, and the mountain-shaped card plate is engaged with the top of the outer mold and the inner mold through the mold slots. The spacing between the mold slots matches the spacing between the outer mold and the inner mold.

[0010] As a further technical solution of this utility model, a plurality of liftable bases for adjusting the height of the base plate are symmetrically arranged on the lower surface of the base plate.

[0011] The beneficial effects of this utility model are as follows: the cross pressure plate, together with the four corner and center clamping screws, securely connects the base plate from the top. At the same time, the mountain-shaped clamping plate surrounds the top of the outer mold and the inner mold, and the gap between them is positioned by the mold slot, which can offset the stress of the thin stainless steel outer mold itself and the resin pouring pressure, avoid the outward arching of the straight part of the outer mold, and ensure the uniform thickness of the coil. The sealing soft rubber gasket on the base plate and the outer and inner clamping rings are adapted to the outer and inner molds, improving the seal and preventing resin leakage. Overall, it ensures the dimensional accuracy and molding quality of the coil, and meets the requirements of power equipment for the stability of coil performance. Attached Figure Description

[0012] Figure 1 This is the front view of the casting mold of this utility model.

[0013] Figure 2 This is a top view of the casting mold of this utility model.

[0014] Figure 3 This is a schematic diagram of the base plate structure of this utility model.

[0015] Figure 4 This is a schematic diagram of the mountain-shaped card plate structure of this utility model. The components are: 1-cross pressure plate; 2-outer mold; 3-base plate; 31-inner retaining ring; 32-outer retaining ring; 33-sealing soft rubber gasket; 4-tightening screw; 41-fastening nut; 5-overflow port; 6-positioning hole; 7-inner mold; 8-mountain-shaped retaining plate; 81-mold slot; 9-liftable base. Detailed Implementation

[0016] The embodiments of this utility model will be described below with reference to the accompanying drawings and related examples. The embodiments of this utility model are not limited to the following examples, and this utility model relates to relevant necessary components in this technical field, which should be regarded as well-known technology in this technical field and can be known and mastered by those skilled in this technical field.

[0017] Combination Figures 1 to 4 As shown, an oblong dry transformer coil casting mold includes an outer mold 2 and an inner mold 7. The inner mold 7 is disposed inside the outer mold 2. A cross pressure plate 1 is provided at the top of the outer mold 2 and the inner mold 7. A base plate 3 is provided at the bottom of the outer mold 2 and the inner mold 7. A clamping screw 4 for connecting the base plate 3 is provided at the four corners and the center of the cross pressure plate 1. A plurality of mountain-shaped clamping plates 8 for fixing the distance between the top of the outer mold 2 and the inner mold 7 are provided between the top of the outer mold 2 and the inner mold 7. The mountain-shaped clamping plates 8 are arranged around the top of the outer mold 2 and the inner mold 7.

[0018] This invention utilizes multiple structural constraints to prevent outward bulging of the straight sections on both sides of the outer mold 2, ensuring uniform overall coil thickness and thus improving coil appearance and operational safety. First, a cross-shaped pressure plate 1 is installed at the top of the outer mold 2 and the inner mold 7. Tightening screws 4 are located at the four corners and center of the cross-shaped pressure plate 1. The two ends of the tightening screws 4 pass through the positioning holes 6 of the cross-shaped pressure plate 1 and the base plate 3, respectively, and are then fixed to the lower surface of the base plate 3 and the upper surface of the cross-shaped pressure plate 1 by fastening nuts 41, forming a stable connection that initially counteracts the outward bulging tendency of the outer mold 2 due to its own stress. Simultaneously, several mountain-shaped clamping plates 8 are arranged around the top of the outer mold 2 and the inner mold 7. These clamping plates 8 are engaged with the outer mold 2 and the inner mold 7 by symmetrical mold slots 81 on their surfaces. The spacing of the mold slots 81 matches the spacing of the outer mold 2 and the inner mold 7, precisely fixing the distance between them and directly limiting the outward deformation of the outer mold 2 under resin casting pressure. By combining the two structures mentioned above, the stress of the outer mold 2 itself and the resin casting pressure can be offset, preventing the straight parts from arching outward, ensuring that the thickness of the straight parts of the coil does not exceed the design value and the thickness of the arc parts is not lower than the standard, thus achieving uniform overall thickness and ultimately improving the appearance and operational safety of the coil.

[0019] As one of the preferred embodiments of this utility model, the bottom plate 3 and the surface of the cross pressure plate 1 are both provided with positioning holes 6 corresponding to the positions of the clamping screw 4, and the two ends of the clamping screw 4 are respectively provided in the positioning holes 6 of the bottom plate 3 and the cross pressure plate 1.

[0020] Furthermore, in the above structure, the two ends of the clamping screw 4 are provided with fastening nuts 41 that are threadedly engaged with the ends of the clamping screw 4. The fastening nuts 41 are respectively provided on the lower surface of the base plate 3 and the upper surface of the cross pressure plate 1.

[0021] In the above structure, the cooperation of the positioning hole 6, the clamping screw 4 and the fastening nut 41 creates a stable upper and lower constraint structure between the cross pressure plate 1 and the base plate 3. The positioning hole 6 is provided through the surface of both the cross pressure plate 1 and the base plate 3, and the position of the positioning hole 6 corresponds exactly to the clamping screw 4. This ensures that the clamping screw 4 can be accurately inserted between the two, avoiding misalignment during installation. This ensures that the subsequent fastening force can be evenly transmitted to the top of the outer mold 2, preventing local deformation of the outer mold 2 due to uneven force.

[0022] The two ends of the clamping screw 4 are inserted into the positioning holes 6 of the base plate 3 and the cross pressure plate 1, respectively, directly connecting the cross pressure plate 1 and the base plate 3 to form a "rigid frame" spanning the outer mold 2 and the inner mold 7. This initially restricts the displacement of the outer mold 2 in the vertical and horizontal directions. The clamping screw 4 is equipped with fastening nuts 41 that are threaded at both ends. The fastening nuts 41 are located on the lower surface of the base plate 3 and the upper surface of the cross pressure plate 1, respectively. When the nuts are tightened, an axial preload is generated, which makes the cross pressure plate 1 firmly press against the top of the outer mold 2. At the same time, it pulls the base plate 3 upward to fit against the bottom of the outer mold 2, so that the outer mold 2 is tightly clamped in the middle. The above structure can effectively offset the stress of the outer mold 2 itself. It can also prevent the straight parts of the outer mold 2 from arching outward by rigid constraints from the top and bottom when the resin is poured. This lays the foundation for the uniformity of coil thickness.

[0023] In one preferred embodiment of this utility model, a sealing soft rubber gasket 33 is provided on the upper surface of the base plate 3, and an outer retaining ring 32 and an inner retaining ring 31 are provided on the upper surface of the sealing soft rubber gasket 33, with the inner retaining ring 31 disposed inside the outer retaining ring 32. Furthermore, in the above structure, the outer mold 2 is disposed inside the outer retaining ring 32 and matches the cross-sectional shape of the outer mold 2, and the inner mold 7 is disposed outside the inner retaining ring 31 and matches the cross-sectional shape of the inner mold 7.

[0024] By sealing the upper surface of the base plate 3 with a soft rubber pad 33, an outer retaining ring 32, and an inner retaining ring 31, the positioning of the outer mold 2 and the inner mold 7 is achieved, and the sealing problem during casting is solved. The soft rubber pad 33 is directly laid on the upper surface of the base plate 3. Its soft properties can closely fit the bottom contact surfaces of the base plate 3 and the outer mold 2 and inner mold 7, filling the tiny gaps between the components and effectively preventing resin from leaking from the bottom of the mold during casting. This avoids insufficient local thickness or molding defects in the coil due to resin loss, and ensures the overall molding quality of the coil.

[0025] The outer retaining ring 32 and the inner retaining ring 31 on the sealing soft rubber gasket 33 are nested inside and outside. The inner shape of the outer retaining ring 32 matches the cross-section of the outer mold 2, and the outer shape of the inner retaining ring 31 matches the cross-section of the inner mold 7. This can limit the installation position of the outer mold 2 and the inner mold 7 on the base plate 3, prevent them from shifting horizontally when installed or subjected to resin pouring pressure, and ensure that the distance between the outer mold 2 and the inner mold 7 always meets the design standard. The outer retaining ring 32 provides lateral restraint to the bottom of the outer mold 2 and can also form a corresponding constraint structure with the top cross pressure plate 1 and the mountain-shaped retaining plate 8, which strengthens the stability of the outer mold 2 from the bottom, makes the coil achieve uniform overall thickness, and improves the appearance regularity and operational safety.

[0026] As one of the preferred embodiments of this utility model, an overflow port 5 is provided through the side wall of the outer mold 2 near the top.

[0027] An overflow port 5 is provided through the side wall of the outer mold 2 near the top. Its core function is to ensure the integrity and stability of the resin casting, and indirectly help maintain the shape of the outer mold 2 and the uniformity of the coil thickness. During resin casting, the cavity between the outer mold 2 and the inner mold 7 must be filled. When the resin flows out from the overflow port 5, it can be visually indicated that the cavity is completely filled, avoiding voids or thinness in the coil due to insufficient filling, and ensuring the overall molding quality of the coil.

[0028] As one of the preferred embodiments of this utility model, the surface of the mountain-shaped card plate 8 is symmetrically provided with mold slots 81, and the mountain-shaped card plate 8 is snapped onto the top of the outer mold 2 and the inner mold 7 through the mold slots 81. The spacing between the mold slots 81 matches the spacing between the outer mold 2 and the inner mold 7.

[0029] The mold slots 81 of the mountain-shaped clamping plate 8 form a stable lateral constraint on the tops of the outer mold 2 and the inner mold 7, preventing the outer mold 2 from arching outward. The mold slots 81 are symmetrically arranged on the surface of the mountain-shaped clamping plate 8, allowing the mountain-shaped clamping plate 8 to fit snugly on the tops of the outer mold 2 and the inner mold 7. At the same time, the spacing between the mold slots 81 perfectly matches the spacing between the outer mold 2 and the inner mold 7, locking the relative positions of the outer mold 2 and the inner mold 7. The constraint of the mountain-shaped clamping plate 8 on the outer mold 2 and the inner mold 7 can counteract the outward pressure generated on the outer mold 2 during resin casting. By fixing the spacing between the outer mold 2 and the inner mold 7, the cavity width between them is ensured to be uniform, thereby ensuring that the thickness of each part of the coil is consistent. This effectively solves the problem of uneven coil thickness caused by deformation of the outer mold 2 in traditional molds, providing a guarantee for improving the regularity of the coil appearance and operational safety.

[0030] As one of the preferred embodiments of this utility model, the lower surface of the base plate 3 is symmetrically provided with a plurality of liftable bases 9 for adjusting the height of the base plate 3.

[0031] The height-adjustable base 9 can achieve horizontal calibration of the base plate 3. If the mold tilts due to unevenness of the worktable during installation or use, adjusting the height of each base can keep the base plate 3 horizontal, preventing uneven distribution of resin due to gravity tilt during pouring, preventing local thickness deviation of the coil, and indirectly helping to maintain the relative position stability of the outer mold 2 and the inner mold 7.

[0032] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A casting mold for an oblong dry transformer coil, comprising an outer mold (2) and an inner mold (7), characterized in that: The inner mold (7) is located inside the outer mold (2). The top of the outer mold (2) and the inner mold (7) are provided with cross pressure plates (1). The bottom of the outer mold (2) and the inner mold (7) are provided with base plates (3). The four corners and the center of the cross pressure plates (1) are provided with clamping screws (4) for connecting the base plates (3). A number of mountain-shaped clamping plates (8) for fixing the distance between the top of the outer mold (2) and the inner mold (7) are provided between the top of the outer mold (2) and the inner mold (7). The mountain-shaped clamping plates (8) are arranged around the top of the outer mold (2) and the inner mold (7).

2. The oval-shaped dry-type transformer coil casting mold according to claim 1, characterized in that: The bottom plate (3) and the surface of the cross pressure plate (1) are both provided with positioning holes (6) corresponding to the position of the clamping screw (4). The two ends of the clamping screw (4) are respectively located in the positioning holes (6) of the bottom plate (3) and the cross pressure plate (1).

3. The oblong dry-type transformer coil casting mold according to claim 1, characterized in that: The clamping screw (4) is provided with fastening nuts (41) at both ends that are threaded to the ends of the clamping screw (4). The fastening nuts (41) are respectively located on the lower surface of the base plate (3) and the upper surface of the cross pressure plate (1).

4. The oval-shaped dry-type transformer coil casting mold according to claim 1, characterized in that: The upper surface of the base plate (3) is provided with a sealing soft rubber gasket (33), and the upper surface of the sealing soft rubber gasket (33) is provided with an outer retaining ring (32) and an inner retaining ring (31), and the inner retaining ring (31) is located inside the outer retaining ring (32).

5. The oval-shaped dry-type transformer coil casting mold according to claim 4, characterized in that: The outer mold (2) is located inside the outer retaining ring (32) and matches the cross-sectional shape of the outer mold (2). The inner mold (7) is located outside the inner retaining ring (31) and matches the cross-sectional shape of the inner mold (7).

6. The oval-shaped dry-type transformer coil casting mold according to claim 1, characterized in that: An overflow port (5) is provided through the side wall near the top of the outer mold (2).

7. The oval-shaped dry-type transformer coil casting mold according to claim 1, characterized in that: The surface of the mountain-shaped card plate (8) is symmetrically provided with mold slots (81). The mountain-shaped card plate (8) is engaged with the top of the outer mold (2) and the inner mold (7) through the mold slots (81). The spacing between the mold slots (81) matches the spacing between the outer mold (2) and the inner mold (7).

8. The oval-shaped dry-type transformer coil casting mold according to claim 1, characterized in that: The lower surface of the base plate (3) is symmetrically provided with several liftable bases (9) for adjusting the height of the base plate (3).

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