Clamp for large casting

Abstract

The invention discloses a fixture for a large casting, and relates to the field of casting processing equipment, the fixture comprises a supporting plate, a base plate is mounted on the side wall of the supporting plate, a hole matched with the casting is formed in the middle of the base plate, a clamping piece and a positioning assembly are arranged at the top of the base plate, and the positioning assembly comprises a positioning piece, a limiting piece, an outer layer abutting piece and an outer layer touch piece. A stable foundation is provided through the horizontally-calibrated supporting plate, the annular casting is preliminarily positioned through the base plate holes, and stress balance of the base plate is guaranteed through uniform connection of the bolts. The multiple sets of clamping pieces are symmetrically distributed along the circumference of a hole, stepped base supporting blocks of the clamping pieces bear a casting, limiting rods guide clamping plates to be not inclined, and adjusting nuts control clamping discs to clamp the casting and prevent crushing. And the wear-resisting plates reduce sliding wear of the clamping plates. The elastic steel sheet of the positioning piece limits the casting in the radial direction, the limiting piece can adjust the spiral rod to be matched with the nylon pressing block to prevent the casting from rotating, the arc-shaped abutting block of the outer-layer abutting piece is matched with the outer diameter and locked, and the rotating ball of the outer-layer touch piece is prevented from being scratched and feeds back displacement.

Description

A fixture for large castings Technical Field

[0001] This invention relates to the field of casting processing equipment, and more particularly to a fixture for large castings. Background Technology

[0002] In heavy industry, aerospace, and shipbuilding, the machining accuracy of large castings directly determines the performance stability of end-use equipment. These castings are generally characterized by their large size, heavy weight, and irregular shape. During machining, they require specialized fixtures for positioning and fixation. If the fixtures are not stable enough, it can easily lead to casting deviation, surface damage, or even safety accidents.

[0003] However, existing fixtures for large castings, while possessing basic support and clamping functions, typically include a support structure for the base plate, a clamping structure for bolts and clamping plates, and a simple stop-type limiting structure. But in practical applications, significant drawbacks exist: First, the clamping structure often uses a single bolt to drive the clamping plate, which lacks a guide and limiting design, making it prone to tilting during clamping and resulting in uneven stress on the casting. Second, the limiting structure is mostly fixed blocks, unable to adapt to castings of different heights and outer diameters, and lacks anti-rotation design, allowing the casting to easily rotate around the support point during machining. Third, the outer abutment components are mostly rigid fixed rods, unable to finely adjust the abutment position according to the curvature of the casting's outer wall, easily causing damage to the casting's outer wall. Furthermore, the connection between the abutment components and the support plate lacks reinforcement, making it prone to loosening over long-term use. Fourth, the connection between the clamping components and the base lacks wear-resistant design, easily leading to wear after frequent loading and unloading of castings, shortening the fixture's service life. Therefore, a new type of fixture for large castings is needed. Summary of the Invention

[0004] The purpose of this invention is to provide a fixture for large castings, which solves the problems of lack of guide limit, inability to adapt to the height and outer diameter of castings, inability to fine-tune castings, and severe wear in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a fixture for large castings, comprising a support plate, a base plate mounted on the side wall of the support plate, a hole adapted to the casting being opened in the middle of the base plate, a clamping member and a positioning assembly provided on the top of the base plate, the positioning assembly including a positioning member, a limiting member, an outer abutment member and an outer contact member, the positioning member being disposed opposite to each other on the top of the base plate and located at the edge of the hole, a limiting member for restricting the rotation of the casting being provided above the base plate, an outer abutment member for abutting the outer side of the casting being limited and positioned is mounted on the side of the base plate away from the support plate, an outer contact member adapted to the outer abutment member is provided on one side of the base plate, and a fixing member for limiting the position is also provided between the outer abutment member and the side connected to the support plate.

[0006] Preferably, the clamping component includes a base, a support block, a limiting rod, a clamping plate, an adjusting rod, an adjusting nut, and a clamping disc. The base is stepped, including a low, middle, and high end. The support block is located at the middle end of the base. A limiting rod is provided on the top surface of the high end of the base. The limiting rod passes through the clamping plate. The clamping plate has a slot. The adjusting nut passes through the slot of the clamping plate and abuts against the top surface of the high end of the base. The clamping disc is located on the bottom surface of the clamping plate away from the adjusting rod.

[0007] Preferably, the clamping member further includes a wear-resistant plate, which is disposed on the side wall where the middle and upper ends of the base meet.

[0008] Preferably, the limiting member includes a limiting block and a spiral rod. The limiting block is convex in shape, and an adjustable spiral rod is wedged into the top of the limiting block.

[0009] Preferably, the fastener includes a fixing block and an insert rod. The fixing block has a convex cross-section, and insert rods are provided on both sides of the protruding end of the fixing block. The insert rods are rotatably connected to both sides of the fixing block.

[0010] Preferably, the outer contact element includes a connecting block, an extension rod, and a rotating ball. The extension rod is provided on the side of the connecting block near the casting, and a rotating ball is installed on the end of the extension rod away from the connecting block.

[0011] Preferably, the outer abutment component includes a support frame, an abutment rod, and a rotating nut. The support frame has a U-shaped cross-section and a through hole inside. The abutment rod is located inside the through hole and passes through the side close to the casting. The rotating nut is sleeved on the inner side of the abutment rod connected to the support frame. The outer wall of the abutment rod is provided with an external thread that matches the rotating nut.

[0012] Compared with the prior art, the beneficial effects of the present invention are:

[0013] 1. The base plate achieves initial positioning through the holes of the casting, and the elastic steel sheet of the positioning component provides radial limit, eliminating the need for repeated manual calibration and significantly shortening the positioning time. The adjustable screw rod of the limit component can accurately adjust the clamping position according to the height of the casting, forming a rigid anti-rotation limit from the top or side, preventing the casting from shifting during processing, effectively reducing processing deviations caused by inaccurate positioning, and improving the processing accuracy of the casting.

[0014] 2. Multiple clamping components are symmetrically distributed along the circumference or side of the casting. The support blocks of the stepped base provide auxiliary support, the limit rod guides the clamping plate to remain tilted, and the adjusting nut can precisely control the clamping force of the clamping plate, which not only prevents the casting from loosening but also prevents excessive clamping from damaging the surface. The inverted conical embedded rod of the fixing component reinforces the connection between the outer abutment component and the support plate, reducing the risk of loosening during long-term use and ensuring the stability and safety of large castings during processing.

[0015] 3. The substrate can be machined with corresponding holes according to the shape of the casting. Square holes have rounded corners, and flexible gaskets can be attached to the inner walls of annular holes to adapt to castings of different shapes. The outer abutment part can adjust the extension length of the abutment rod by rotating the nut. With the help of arc or rectangular abutment blocks, it can adapt to castings of different outer diameters or sizes. The adjustable structure of the limiting part and clamping part also supports specification changes, eliminating the need to customize special fixtures for a single casting and reducing equipment investment costs.

[0016] 4. The wear-resistant plate of the clamping component reduces the wear on the base when the clamping plate slides, extending the service life of the fixture body; the nylon pressure block of the limiting component and the rotating ball of the outer contact component prevent metal parts from directly contacting the casting, preventing scratches and indentations on the surface of the casting; the flexible rotation of the rotating ball can also buffer the impact of small displacements, protecting the machined surface of the casting and reducing the rigidity loss of the fixture components.

[0017] 5. All adjustment components of the fixture support manual operation without the need for complicated tools; when loading and unloading castings, it is only necessary to loosen the adjustment components and pull out the elastic pins of the fixing components, without disassembling the main body of the fixture, simplifying the operation process; the rotating ball of the outer contact component can intuitively reflect the displacement status of the casting, which is convenient for timely adjustment, reduces processing interruption time, and improves overall processing efficiency. Attached Figure Description

[0018] Figure 1 is a top view of the overall structure of the product of the present invention;

[0019] Figure 2 is a schematic diagram of the overall structure of the product of the present invention;

[0020] Figure 3 is a schematic diagram of the clamping component structure of the product of the present invention;

[0021] Figure 4 is a schematic diagram of the limiting component structure of the product of the present invention;

[0022] Figure 5 is a schematic diagram of the fastener structure of the product of the present invention;

[0023] Figure 6 is a schematic diagram of the outer contact component structure of the product of the present invention;

[0024] Figure 7 is a schematic diagram of the outer abutment structure of the product of the present invention.

[0025] In the diagram: 1. Support plate; 2. Base plate; 3. Clamping component; 31. Base; 32. Support block; 33. Wear-resistant plate; 34. Limiting rod; 35. Clamping plate; 36. Adjusting rod; 37. Adjusting nut; 38. Clamping disc; 4. Positioning component; 5. Limiting component; 51. Limiting block; 52. Spiral rod; 6. Outer abutment component; 61. Support frame; 62. Abutment rod; 63. Rotating nut; 7. Outer contact component; 71. Connecting block; 72. Extension rod; 73. Rotating ball; 8. Guardrail; 10. Fixing component; 101. Fixing block; 102. Embedded rod. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1

[0028] This invention relates to a fixture for large castings. As shown in Figures 1-7, the support plate 1 is first leveled by placing a level against the top surface of the support plate and adjusting the foot pads under the machine tool table until the level shows no tilt deviation, thus preventing casting offset due to support tilt. Then, the base plate 2 is connected to the side wall of the support plate 1 using high-strength bolts. The bolts are evenly distributed along the connection surface to ensure balanced force on the base plate. The hole in the middle of the base plate needs to be pre-machined according to the inner diameter of the annular casting, and the inner wall of the hole is chamfered to prevent scratches on the casting during insertion. If there are slight protrusions on the inner wall of the casting, flexible gaskets can be attached to the inner wall of the hole, which does not affect the positioning accuracy and can adapt to the small irregularities of the casting's inner wall.

[0029] Furthermore, multiple sets of clamping parts 3 are symmetrically installed on the top of the substrate 2 along the circumference of the hole, the number of which is determined to match the circumferential force balance of the annular casting.

[0030] The stepped base 31 has three levels: low, medium, and high, with the height adapted to the support requirements of the casting. The middle support block 32 adopts a cuboid structure, and its size fits the support range of the bottom edge of the casting. The top surface of the support block fits the bottom edge of the casting to help distribute the weight of the casting. The side wall connecting the middle and high ends of the base is fixed with a wear-resistant plate 33 by countersunk bolts. The wear-resistant plate is made of high manganese steel and the surface is polished to reduce the frictional resistance when the clamping plate slides, while avoiding frequent wear on the side wall of the base.

[0031] The limiting rod 34 is made of high-strength round rod with external thread at the top. The diameter of the hole through the clamping plate 35 is slightly larger than the diameter of the limiting rod, ensuring that the clamping plate can slide smoothly up and down without radial wobble. The clamping plate 35 is made of high-strength steel plate and has a waist-shaped groove. The size of the waist-shaped groove can be adapted to the slight positional deviation of the adjusting nut 37, which is convenient for installation and debugging.

[0032] The adjusting nut 37 is selected to match the base. During installation, a spring washer is installed between the nut and the clamping plate 35 to prevent the nut from loosening due to machining vibration. When rotating the adjusting nut, a torque wrench is used to control the clamping force. After the clamping plate 38 contacts the top surface of the casting, continue to adjust slowly until the clamping force reaches a state where the casting is not loose and there are no indentations on the surface. This avoids both insufficient clamping force causing the casting to loosen and excessive clamping force damaging the surface of the casting. The clamping plate 38 adopts a circular structure with a flexible anti-slip pad attached to the bottom surface. The surface of the anti-slip pad has anti-slip texture to enhance the friction with the top surface of the casting, while isolating direct metal contact and protecting the surface machining accuracy of the casting.

[0033] Furthermore, the positioning component 4 uses an L-shaped steel plate as its main body. An elastic steel sheet is welded to the inner side of the positioning component on the side that contacts the outer wall of the casting. The elastic steel sheet has a slight deformation allowance to accommodate minor curvature deviations in the outer wall of the casting. The positioning components are evenly distributed along the edge of the holes and fixed to the base plate with bolts. The bolt holes are elongated, allowing for fine adjustment of the contact distance between the positioning component and the outer wall of the casting, ensuring that the elastic steel sheet of each positioning component is in close contact with the outer wall of the casting, forming a radial limit.

[0034] The bottom width of the U-shaped limiting block 51 of the limiting component 5 is greater than its top width, enhancing the stability of the limiting block on the substrate. The spiral rod 52 is a spiral rod with trapezoidal threads, and a handwheel for easy manual adjustment is welded to the top. During installation, the limiting block is first fixed to the substrate 2 with expansion bolts, with the limiting block positioned on the outside of the casting. Then, the handwheel is turned clockwise to slowly move the spiral rod 52 downwards. When the bottom of the spiral rod approaches the top surface of the casting, a nylon pressure block is added to the bottom of the spiral rod. The handwheel is continued to be turned until the nylon pressure block is completely in contact with the top surface of the casting, and then the rotation is stopped. The nylon pressure block can prevent the metal spiral rod from directly damaging the top surface of the casting. At the same time, the trapezoidal thread structure has a self-locking function to prevent the spiral rod from loosening during processing. If the height of the casting increases, simply continue to turn the handwheel to move the spiral rod down to the appropriate height, demonstrating the height adaptability of the limiting component.

[0035] The U-shaped support frame 61 of the outer abutment part 6 is welded from square tubing. The internal through-hole size of the support frame is adapted to the sliding requirements of the abutment rod 62, ensuring smooth sliding of the abutment rod. The abutment rod 62 is made of high-strength round rod with external threads machined on the outer wall. The clearance between the abutment rod and the rotating nut 63 meets the adjustment accuracy requirements. During installation, the support frame is first welded to the side of the base plate 2 away from the support plate, with the height of the support frame aligned with the center height of the casting. Then, the abutment rod is inserted into the through-hole of the support frame, and the rotating nut 63 is fitted onto the end of the abutment rod near the inner side of the support frame. By turning the nut clockwise with a wrench, the abutment rod is pushed out towards the casting. When the end of the abutment rod approaches the outer wall of the casting, an arc-shaped abutment block is welded at the end with an arc radius matching the outer diameter of the casting. The nut is continued to be turned until the arc-shaped abutment block fits tightly against the outer wall of the casting. At this point, a locking nut is installed on the outside of the nut to prevent the nut from reversing due to processing vibration.

[0036] The connecting block 71 of the outer contact member 7 is fixed to the base plate 2 near the outer abutment member by bolts. A U-shaped groove is provided on the side of the connecting block, and the extension rod 72 is connected to the U-shaped groove by a pin. It can rotate around the pin at a certain angle to adapt to the outer wall of the casting at different angles. A spherical groove is provided at the end of the extension rod away from the connecting block. The rotating ball 73 is embedded in the groove. Lubricant is applied between the rotating ball and the groove to ensure that the rotating ball can rotate flexibly. During installation, the angle of the extension rod is adjusted so that the rotating ball makes light contact with the outer wall of the casting. The contact pressure is such that the rotating ball can rotate slightly with external force. When the casting undergoes slight displacement due to vibration during processing, the rotating ball can slide with the outer wall of the casting to avoid rigid collision that could scratch the outer wall of the casting. At the same time, the contact state of the rotating ball can be used to visually determine whether the casting has undergone abnormal displacement.

[0037] Furthermore, the bottom of the U-shaped fixing block 101 of the fixing member 10 is attached to the side wall of the support plate 1, and the contact surface is roughened to enhance friction. The embedded rods 102 on both sides of the protruding end of the fixing block are provided with an inverted cone structure, and the support plate has a conical groove matching the inverted cone of the embedded rod at the corresponding position. During installation, one end of the fixing block is first welded and fixed to the support frame 61 of the outer abutment member, and the other end is attached to the side wall of the support plate. Then, the embedded rod is rotated with a wrench so that the inverted cone at the end of the embedded rod is slowly inserted into the conical groove of the support plate until the embedded rod can no longer be rotated. To prevent the embedded rod from loosening, a hole is drilled on the side of the fixing block, and a positioning hole is opened through the embedded rod. An elastic pin is inserted into the positioning hole to lock the embedded rod. After processing, when disassembling the casting, the elastic pin should be pulled out first, the insert rod should be rotated in the opposite direction to disengage from the slot, and then the locking nut and rotating nut of the outer abutment part, the spiral rod of the limiting part, and the adjusting nut of the clamping part should be loosened. Finally, the casting should be taken out from the hole in the base plate. The entire loading and unloading process does not require disassembling the fixture body, which improves the efficiency of operation.

[0038] In practical use: A stable foundation is provided by a horizontally calibrated support plate 1; the hole in the base plate 2 initially positions the annular casting; and the evenly connected bolts ensure the force balance of the base plate 2. Multiple sets of clamping parts 3 are symmetrically distributed along the circumference of the hole. The stepped base 31 and support block 32 of the clamping parts 3 support the casting; the limiting rod 34 guides the clamping plate 35 to prevent tilting; the adjusting nut 37 controls the clamping disc 38 to clamp the casting and prevent pressure damage; the wear-resistant plate 33 reduces sliding wear of the clamping plate 35. The positioning part 4 uses an elastic steel sheet to radially limit the casting; the limiting part 5 has an adjustable spiral rod 52 with a nylon pressure block to prevent the casting from rotating; the outer abutment part 6 has an arc-shaped abutment block that adapts to the outer diameter and locks it in place; the outer contact part 7 has a rotating ball 73 that prevents scratches and provides displacement feedback; the fixing part 10 has an inverted conical embedded rod 102 to reinforce the outer abutment part 6. The whole system works together to achieve stable clamping of the casting and meet the needs of milling.

[0039] Example 2

[0040] The holes in the substrate 2 are machined into square shapes, with dimensions suitable for the bottom of the square casting. The four corners of the inner wall of the hole are rounded to avoid scratching the corners of the casting. The positioning parts 4 are adjusted into multiple sets and installed on the outer sides of the four corners of the holes in the substrate. The inner side of the positioning parts is provided with right-angled abutment plates that fit against the corners of the square casting. By adjusting the installation position of the positioning parts, it is ensured that the casting does not move radially within the holes.

[0041] The clamping component 3 is installed at the midpoint of the four sides of the square casting on the top of the substrate. The support block 32 of the base 31 is adjusted to a right trapezoidal structure to fit the angle between the side wall and the bottom surface of the square casting. Multiple sets of limiting components 5 are added and installed on the outside of the two opposite side walls of the square casting. A rectangular pressure block is added to the bottom of the spiral rod 52 to fit against the side wall of the casting and press against the casting from the side. Together with the top limiting component, it forms a two-way anti-rotation limiting to prevent the casting from rotating around the vertical axis during drilling.

[0042] The end of the abutment rod of the outer abutment member 6 is replaced with a rectangular abutment block that fits against the side wall of the square casting. The height of the support frame 61 is adjusted to be aligned with the center height of the casting. The extension rod of the outer contact member 7 is adapted to the size of the casting. The rotating ball contacts the side wall of the square casting. When the casting undergoes a slight displacement due to the force of drilling, the rotating ball slides along the side wall to provide real-time feedback on the status of the casting.

[0043] In practical use: the square hole of the base plate 2 is adapted to the bottom of the square casting, and the rounded transition prevents scratches on the edges and corners. The right-angle abutment plate of the positioning component 4 clamps the edges and corners of the casting to prevent radial movement. The clamping components 3 are distributed along the midpoints of the four sides of the casting. The right-angled trapezoidal support block 32 of the clamping component 3 fits against the angle between the side wall and the bottom surface of the casting to ensure stable support. The limiting component 5 is equipped with a side assembly, and the rectangular pressure block, together with the top limiting component 5, forms a two-way anti-rotation limiting to prevent the casting from rotating during drilling. The rectangular abutment block of the outer layer abutment component 6 fits against the square side wall, and the support frame 61 is aligned with the center of the casting. The extension rod 72 of the outer layer contact component 7 is adapted to the size, and the rotating ball 73 slides with the slight displacement of the casting and provides feedback on the status. All components are adapted to the structure of the square casting and work together to achieve precise positioning and stable clamping, meeting the requirements of drilling.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fixture for large castings, comprising a support plate (1), characterized in that: The support plate (1) has a base plate (2) installed on its side wall. The base plate (2) has a hole in the middle that is adapted to the casting. The top of the base plate (2) is provided with a clamping member (3) and a positioning component. The positioning component includes a positioning member (4), a limiting member (5), an outer abutment member (6) and an outer contact member (7). The positioning member (4) is arranged opposite to the top of the base plate (2) and is located at the edge of the hole. The upper part of the base plate (2) is provided with a limiting member (5) that restricts the rotation of the casting. The side of the base plate (2) away from the support plate (1) is provided with an outer abutment member (6) that abuts against the outer side of the casting and limits its movement. The side of the base plate (2) is provided with an outer contact member (7) that is adapted to the outer abutment member (6). A fixing member (10) with a limiting function is also provided between the outer abutment member (6) and the side of the support plate (1) that is connected to the support plate (1).

2. The fixture for large castings according to claim 1, characterized in that: The clamping component (3) includes a base (31), a support block (32), a limiting rod (34), a clamping plate (35), an adjusting rod (36), an adjusting nut (37), and a clamping disc (38). The base (31) is stepped, including a low, a middle, and a high end. The support block (32) is located at the middle end of the base (31). The top surface of the high end of the base (31) is provided with a limiting rod (34). The limiting rod (34) passes through the clamping plate (35). The clamping plate (35) has a slot. The adjusting nut (37) passes through the slot of the clamping plate (35) and abuts against the top surface of the high end of the base (31). The clamping disc (38) is located away from the adjusting rod (36) on the bottom surface of the clamping plate (35).

3. The fixture for large castings according to claim 2, characterized in that: The clamping member (3) also includes a wear-resistant plate (33), which is disposed on the side wall connecting the middle and high ends of the base (31).

4. The fixture for large castings according to claim 1, characterized in that: The limiting member (5) includes a limiting block (51) and a spiral rod (52). The limiting block (51) is convex in shape, and an adjustable spiral rod (52) is inserted into the top of the limiting block (51).

5. The fixture for large castings according to claim 1, characterized in that: The fastener (10) includes a fixing block (101) and an insert rod (102). The cross-section of the fixing block (101) is convex. The two sides of the protruding end of the fixing block (101) are provided with insert rods (102). The insert rods (102) are rotatably connected to the two sides of the fixing block (101).

6. The fixture for large castings according to claim 1, characterized in that: The outer contact element (7) includes a connecting block (71), an extension rod (72) and a rotating ball (73). The extension rod (72) is provided on the side of the connecting block (71) close to the casting, and the rotating ball (73) is installed on the end of the extension rod (72) away from the connecting block (71).

7. The fixture for large castings according to claim 1, characterized in that: The outer abutment member (6) includes a support frame (61), an abutment rod (62), and a rotating nut (63). The support frame (61) has a U-shaped cross section and a through hole inside. The abutment rod (62) is located inside the through hole and passes through the side close to the casting. The rotating nut (63) is sleeved on the inner side of the abutment rod (62) connected to the support frame (61). The outer wall of the abutment rod (62) is provided with an external thread that matches the rotating nut (63).

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