A simple hoisting device for large sand cores

Abstract

This application discloses a simple hoisting device for large sand cores, including a hinged short arm assembly consisting of two short connecting rods, and a cross-arm assembly consisting of two long connecting rods, each hinged to the end of one of the two short connecting rods. The two long connecting rods are connected at their midpoint by a hinge structure, forming a cross-arm structure that can rotate relative to each other. When the ends of the two short connecting rods approach each other, the two long connecting rods also approach each other under the linkage. A sand core clamping component is disposed at the end of the long connecting rods for directly contacting and clamping the large sand core. A clamping angle limiting mechanism is installed between the first and second long connecting rods, which can precisely control the clamping angle between the two long connecting rods. After initial hoisting, the clamping angle is fixed. During subsequent hoisting, regardless of how the device shakes, the relative position change between the long connecting rods is constrained due to the limited angle, thus ensuring that the clamping force of the sand core clamping component on the sand core does not increase with shaking.

Description

Technical Field

[0001] This application belongs to the field of sand core hoisting, and in particular relates to a simple hoisting device for large sand cores. Background Technology

[0002] In the casting production field, sand cores are an indispensable and crucial component. Sand cores are primarily used to form the internal cavity structure of castings, and their quality directly affects the dimensional accuracy, surface quality, and internal microstructure of the casting. In the sand core production process, the transfer stage is critical and faces numerous challenges. After completion, sand cores require multiple transfers, hoisting, and flipping operations before reaching subsequent processes. Ensuring the integrity of the sand cores is paramount, as any impact can lead to defects, thus affecting the quality of the casting. For lighter sand cores, existing transfer equipment and operating methods are sufficient to some extent. However, for large sand cores weighing ≥100kg, the situation becomes much more complex. Due to their large size and weight, large sand cores require specialized lifting equipment for hoisting during transfer.

[0003] Currently, a gravity clamp lifting fixture is used for transporting large sand cores. This fixture works on the principle of leverage, using the weight of the object to trigger clamping action on both sides. When the fixture carries a sand core, the weight of the core causes the fixture's mechanical structure to move, thus automatically clamping the sand core with the jaws on both sides. From a design perspective, this fixture offers convenience and automation, improving the efficiency of sand core transport to some extent. However, in practical applications, for heavier, larger sand cores, the structure is often complex, containing multiple cavities and weak points, and the surface shape is often irregular. During transport, the movement of the fixture causes swaying, which alters the clamping force on both sides of the fixture. Specifically, initially, the fixture may apply a certain initial clamping force as designed. However, as the transport progresses, due to the continued swaying, the clamping force gradually increases, becoming increasingly tight. This excessive clamping force can cause serious damage to the sand core. On the one hand, the clamping points on both sides of the sand core can deform due to excessive pressure, causing changes in the shape of the sand core. On the other hand, this deformation can further lead to cracks in the center of the sand core. Cracks in the center of the sand core not only affect the internal quality of the casting, causing problems such as leakage and insufficient strength during use, but in severe cases, they can even render the entire casting unusable, resulting in huge economic losses for the enterprise. Therefore, it is evident that the existing technology needs further improvement and enhancement. Utility Model Content

[0004] This utility model provides a simple lifting device for large sand cores, which solves the problem that although gravity clamp lifting fixtures are convenient, in actual application, due to the complex structure and irregular surface of large sand cores, the clamping force of the lifting fixture on the sand core gradually increases due to the shaking during transportation. Excessive clamping force will cause deformation at the clamping positions on both sides of the sand core and cracks in the middle, affecting the quality of the casting.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A simple hoisting device for large sand cores, comprising: The articulated short arm assembly consists of two short links, one end of which is connected to each other by a hinge. The cross-arm assembly includes two long links, which are hinged to the ends of two short links respectively. The two long links are connected by a hinge structure at the middle intersection position to form a cross-arm structure that can rotate relative to each other. When the ends of the two short links approach each other, the two long links also approach each other due to the linkage. The sand core clamping component is located at the end of the long connecting rod and is used to directly contact and clamp large sand cores; The clamping angle limiting mechanism is installed between the first and second long connecting rods. It can control the clamping angle between the two long connecting rods to prevent the sand core from deforming or breaking due to excessive clamping force when hoisting the sand core.

[0006] In a preferred implementation, the clamping angle limiting mechanism includes an arc-shaped frame disposed on one of the long connecting rods, the arc-shaped frame having an arc-shaped cavity inside; an arc-shaped insert is disposed on the other long connecting rod, the arc-shaped insert being inserted into the arc-shaped cavity; when the two long connecting rods are relatively close or far apart, the arc-shaped insert is inserted into or withdrawn from the arc-shaped cavity, fixing the position of the arc-shaped insert within the arc-shaped cavity to control the clamping angle between the two long connecting rods.

[0007] In a preferred embodiment, the arc-shaped cavity is provided with rotating teeth, and the arc-shaped insert is provided with mating teeth. The rotating teeth and the mating teeth are engaged and connected. When the arc-shaped insert is inserted into or removed from the arc-shaped cavity, the mating teeth rotate. By restricting the rotation of the rotating teeth, the movement of the arc-shaped insert can be restricted, thereby limiting the clamping angle.

[0008] In a preferred embodiment, the rotating tooth is fixedly sleeved on the outside of the rotating shaft, the upper and lower walls of the arc-shaped cavity are embedded with bearings, the rotating shaft is connected to the inner ring of the bearing and can rotate around its own axis, the end of the rotating shaft located outside the arc-shaped cavity has an edge, and an anti-rotation component adapted to the inner cavity of the end of the rotating shaft is detachably sleeved on the outside of the rotating shaft and detachably connected to the arc-shaped frame to restrict the rotation of the rotating shaft.

[0009] In a preferred embodiment, the anti-rotation component is a bushing with a wide diameter section and a narrow diameter section. The narrow diameter section has an angular inner cavity, and the outer wall of the arc-shaped frame is provided with an annular embedding groove. The wide diameter section is interference-fitted into the annular embedding groove.

[0010] In a preferred embodiment, the end of the long connecting rod is provided with a rotating connecting block, the rotating connecting block has a mounting hole, two deep groove ball bearings are installed in the mounting hole, the support shaft is connected to the deep groove ball bearings, one end of the support shaft is connected to the sand core clamping component, and the other end is connected to the handle.

[0011] In a preferred implementation, an anti-rotation frame is also included, which is detachably connected to the handle and the long connecting rod.

[0012] In a preferred implementation, the shape of the sand core clamping component is adapted to the shape of the sand core overlap position and is detachably connected to the support shaft.

[0013] In a preferred embodiment, the long connecting rod includes an integrally formed short vertical section, a long vertical section, and an inclined section connecting the short vertical section and the long vertical section, wherein the angle between the inclined section and the short vertical section and the long vertical section is 120°, and the sand core clamping assembly is installed at the end of the long vertical section.

[0014] In a preferred implementation, one end of one of the two short connecting rods is provided with a lifting part, and a lifting hole is provided on the lifting part.

[0015] The above structure has the following beneficial effects: 1. A linkage structure is formed by a hinged short arm assembly and a cross-arm long arm assembly. A clamping angle limiting mechanism is installed between the two long connecting rods, enabling precise control of the clamping angle between them. After initial hoisting, the clamping angle is fixed. During subsequent hoisting, regardless of any shaking of the device, the relative positional changes between the long connecting rods are constrained due to the limited angle, thus ensuring that the clamping force of the sand core holding component on the sand core does not increase with shaking. This avoids the problem of deformation at the clamping positions on both sides of the sand core and cracks in the middle due to excessive clamping force, thereby ensuring the integrity of the sand core and improving the quality of the casting.

[0016] 2. The long connecting rod is designed as a multi-segment structure with an included angle of 120°, which can automatically lock the sand core when the tooling is lifted, effectively preventing the sand core clamping parts from detaching from the sand core during transportation, thus avoiding problems such as the sand core falling or tilting.

[0017] 3. The design of using double deep groove ball bearings and support shafts enables 360° rotation while clamping the sand core, allowing for comprehensive inspection and repair of the sand core during hoisting.

[0018] 4. The sand core clamping component and the sand core overlap position adopt a conformal design with a 1.0mm gap. When transporting the sand core, the sand core clamping component can be smoothly placed into the hoisting area and the sand core can be fully positioned, so as to realize the smooth hoisting of the sand core and avoid problems such as loosening or falling off the sand core during rotation. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain this application and do not constitute an undue limitation of the present invention. In the drawings: Figure 1 A schematic structural diagram illustrating one embodiment of the simple hoisting device for large sand cores according to this application is shown. Figure 2 A schematic diagram illustrating the internal fit of one embodiment of the arc-shaped frame and arc-shaped insert of this application is shown. Figure 3 This application is illustrated. Figure 2 An enlarged structural schematic diagram of one embodiment of part A in the diagram; Figure 4 A schematic three-dimensional structural diagram illustrating one embodiment of the simple hoisting device for large sand cores according to this application is shown. Figure 5 This application is illustrated. Figure 4 An enlarged structural schematic diagram of one embodiment of Part B; Figure 6 An exploded structural diagram illustrating an illustrative embodiment of the simple hoisting device for large sand cores according to this application is shown. Label Explanation: 10. Short connecting rod; 100. Lifting part; 11. Long connecting rod; 110. Short vertical rod; 111. Long vertical rod; 112. Inclined section; 12. Sand core clamping component; 13. Clamping angle limiting mechanism; 130. Arc frame; 1300. Annular embedded groove; 131. Arc insert; 1310. Mating teeth; 132. Rotating teeth; 133. Rotating shaft; 14. Anti-rotation component; 140. Wide diameter section; 141. Narrow diameter section; 15. Rotating connecting block; 16. Deep groove ball bearing; 17. Support shaft; 18. Anti-rotation frame; 19. Handle. Detailed Implementation

[0020] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit and scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0021] In the description of this utility model, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In this utility model, unless otherwise expressly specified and limited, the first feature being "upper" or "lower" than the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium.

[0022] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral unit; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. However, specifying a direct connection indicates that the two main bodies at the connection point are not connected by an intermediate structure, but are simply connected to form a whole through a connecting structure. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0023] In this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0024] The present invention will now be described with reference to the accompanying drawings.

[0025] The specific solution adopted is as follows: like Figure 1-6 As shown, this utility model provides a simple hoisting device for large sand cores, comprising: The articulated short arm assembly consists of two short links 10, with one end of the two short links connected to each other by a hinge. The cross-arm assembly includes two long links, which are hinged to the ends of two short links respectively. The two long links are connected by a hinge structure at the middle intersection position to form a cross-arm structure that can rotate relative to each other. When the ends of the two short links approach each other, the two long links also approach each other due to the linkage. The sand core clamping component 12 is located at the end of the long connecting rod 11 and is used to directly contact and clamp large sand cores; The clamping angle limiting mechanism 13 is installed between the first long connecting rod and the second long connecting rod. It can control the clamping angle between the two long connecting rods to avoid excessive clamping force during hoisting of the sand core, which could cause deformation or breakage of the sand core.

[0026] The simplified hoisting device for large sand cores described in this application comprises a linkage structure formed by a hinged short-arm assembly and a cross-arm long-arm assembly. A clamping angle limiting mechanism is installed between two long connecting rods 11, enabling precise control of the clamping angle between them. After initial hoisting, the clamping angle is fixed. During subsequent hoisting, regardless of any swaying of the device, the relative positional changes between the long connecting rods are constrained due to the limited angle, thus ensuring that the clamping force of the sand core clamping components on the sand core does not increase with swaying. This avoids the problem of deformation at the clamping positions on both sides of the sand core and cracks in the middle caused by excessive clamping force, thereby ensuring the integrity of the sand core, improving the quality of the casting, and providing a reliable solution for the safe and stable hoisting of large sand cores.

[0027] In a preferred embodiment of this application, the clamping angle limiting mechanism includes an arc-shaped frame 130 mounted on one of the long connecting rods, the arc-shaped frame having an arc-shaped cavity inside; and an arc-shaped insert 131 mounted on the other long connecting rod. The structure is relatively simple, with fewer parts, reducing manufacturing costs. The relative approach or distance between the two long connecting rods is achieved by inserting and withdrawing the arc-shaped insert within the arc-shaped cavity, and the motion principle is clear and easy to understand. When the clamping angle needs to be adjusted, the operator can easily operate and control it. In practical applications, the clamping angle can be adjusted to the most suitable position according to large sand cores of different shapes and sizes. The position of the arc-shaped insert within the arc-shaped cavity is fixed. The fixing method can be bolt fixing, for example, by setting multiple holes on the arc-shaped insert and the arc-shaped frame. After the holes correspond, the bolts are inserted into the holes to ensure that the sand core clamping component can firmly and stably clamp the sand core.

[0028] Furthermore, the arc-shaped cavity is provided with a rotating tooth 132, and the arc-shaped insert is provided with a mating tooth. The rotating tooth and the mating tooth are meshed and connected. When the arc-shaped insert is inserted into or removed from the arc-shaped cavity, the mating tooth 1310 rotates. By restricting the rotation of the rotating tooth, the movement of the arc-shaped insert can be restricted, thereby achieving the limitation of the clamping angle.

[0029] The clamping angle limiting design achieves this by engaging rotating teeth with mating teeth. Compared to using bolts with multiple holes for limiting, this method offers a wider angle adjustment range. The bolt-limiting method requires pre-drilling multiple fixed holes on the arc-shaped frame, each corresponding to a specific clamping angle. This severely limits angle adjustment to these discrete holes, significantly restricting the adjustment range. In contrast, the rotating teeth and mating teeth design allows the arc-shaped insert to rotate continuously within the arc-shaped cavity, with the mating teeth rotating accordingly. Theoretically, this allows for arbitrary angle adjustments within a certain range, greatly expanding the clamping angle adjustment range and accommodating sand cores of various sizes.

[0030] Specifically, the rotating gear is fixedly sleeved on the outside of the rotating shaft 133, while the upper and lower walls of the arc-shaped cavity are embedded with bearings. The rotating shaft is connected to the inner ring of the bearing and can rotate around its own axis, allowing the rotating shaft and rotating gear to rotate smoothly and flexibly within the arc-shaped cavity. The end of the rotating shaft outside the arc-shaped cavity has an edge, which allows the anti-rotation component to effectively engage with the rotating shaft. When the anti-rotation component is sleeved outside the rotating shaft, it can better restrict the rotation of the rotating shaft and prevent it from rotating accidentally due to external forces during hoisting. The anti-rotation component, which is adapted to the inner cavity of the rotating shaft end, is detachably sleeved outside the rotating shaft and detachably connected to the arc-shaped frame. The anti-rotation component 14 is a bushing with a wide diameter section 140 and a narrow diameter section 141. The narrow diameter section has an angular inner cavity, and the outer wall of the arc-shaped frame is provided with an annular embedding groove. The wide diameter section is interference-fitted into the annular embedding groove.

[0031] When it is necessary to limit the clamping angle, the operator can install an anti-rotation device to limit the rotation of the rotating shaft and fix the clamping angle.

[0032] In a preferred embodiment of this application, a rotating connecting block 15 is provided at the end of the long connecting rod, and two deep groove ball bearings 16 are installed in the mounting holes of the connecting block. Deep groove ball bearings have advantages such as low friction coefficient, high limiting speed, and simple structure, and can withstand radial loads and a certain axial load. The support shaft is connected to the deep groove ball bearings, allowing the support shaft to rotate freely within the bearings. This design provides the basic motion conditions for the flipping of the sand core clamping component, ensuring the smoothness of the flipping process. One end of the support shaft 17 is connected to the sand core clamping component, and the other end is connected to a handle. The sand core clamping component is used to firmly clamp the sand core, ensuring that the sand core will not fall off during the flipping process; the handle provides the operator with a point of force to manually control the rotation of the support shaft. By operating the handle, force can be easily applied, causing the support shaft to drive the sand core clamping component and the sand core to flip together.

[0033] Furthermore, it also includes an anti-rotation frame 18, with a detachable handle 19 and a long connecting rod. For example, an L-shaped frame is used to connect the handle and the long connecting rod via bolts. During the sand core hoisting process, especially when moving the sand core to the designated position, it is necessary to ensure that the sand core maintains a stable posture to avoid safety accidents such as collisions, damage, or falling due to accidental overturning. The presence of the anti-rotation frame can effectively lock the relative position of the handle and the long connecting rod, preventing the support shaft from rotating, thereby ensuring the safety of the sand core during hoisting.

[0034] In a preferred embodiment of this application, the shape of the sand core clamping component is adapted to the shape of the sand core overlap position and is detachably connected to the support shaft. Because the shape of the sand core clamping component precisely matches the sand core overlap position, it can fit tightly against the sand core surface when clamping the sand core, forming a large contact area and friction. This tight fit effectively reduces the swaying and displacement of the sand core during hoisting and flipping, improving clamping stability. When processing sand cores of different shapes or sizes, operators can easily disassemble the original sand core clamping component and install a clamping component suitable for the new sand core. This quick changeover capability greatly shortens equipment adjustment time and improves production efficiency. The sand core clamping component is provided with threaded holes, and the end of the support shaft is machined with threads; the threaded connection between the two achieves reliable connection and quick disassembly.

[0035] In a preferred embodiment of this application, the long connecting rod includes an integrally formed short vertical section 110, a long vertical section 111, and an inclined section 112 connecting the short and long vertical sections. The angle between the inclined section and both the short and long vertical sections is 120 degrees. The sand core clamping assembly is installed at the end of the long vertical section. The integral molding process eliminates the connection gaps between the short, long, and inclined sections, avoiding stress concentration and weak points that may occur with traditional connection methods such as welding and bolting. The long connecting rod is designed as a multi-segment structure with an angle of 120°, which allows the tooling to automatically lock the sand core when lifting it, effectively preventing the sand core clamping assembly from detaching from the sand core during transportation, thus avoiding problems such as the sand core falling or tilting.

[0036] In a preferred embodiment of this application, one end of one of the two short connecting rods is provided with a lifting part 100, and a lifting hole is provided on the lifting part to facilitate lifting connection.

[0037] For any parts not mentioned in this utility model, existing technologies can be used or referenced.

[0038] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this utility model, and these should all be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A simple hoisting device for large sand cores, characterized in that, include: The articulated short arm assembly consists of two short links, one end of which is connected to each other by a hinge. The cross-arm assembly includes two long links, which are hinged to the ends of two short links respectively. The two long links are connected by a hinge structure at the middle intersection position to form a cross-arm structure that can rotate relative to each other. When the ends of the two short links approach each other, the two long links also approach each other due to the linkage. The sand core clamping component is located at the end of the long connecting rod and is used to directly contact and clamp large sand cores; The clamping angle limiting mechanism is installed between the first and second long connecting rods. It can control the clamping angle between the two long connecting rods to prevent the sand core from deforming or breaking due to excessive clamping force when hoisting the sand core.

2. The simple hoisting device for large sand cores according to claim 1, characterized in that, The clamping angle limiting mechanism includes an arc-shaped frame mounted on one of the long connecting rods, the arc-shaped frame having an arc-shaped cavity inside; an arc-shaped insert is mounted on the other long connecting rod, the arc-shaped insert being inserted into the arc-shaped cavity; when the two long connecting rods are relatively close or far apart, the arc-shaped insert is inserted into or withdrawn from the arc-shaped cavity, fixing the position of the arc-shaped insert within the arc-shaped cavity to control the clamping angle between the two long connecting rods.

3. The simple hoisting device for large sand cores according to claim 2, characterized in that, The arc-shaped cavity is provided with rotating teeth, and the arc-shaped insert is provided with mating teeth. The rotating teeth and the mating teeth are meshed and connected. When the arc-shaped insert is inserted into or removed from the arc-shaped cavity, the mating teeth rotate. By restricting the rotation of the rotating teeth, the movement of the arc-shaped insert can be restricted, thereby achieving the limitation of the clamping angle.

4. The simple hoisting device for large sand cores according to claim 3, characterized in that, The rotating gear is fixedly sleeved on the outside of the rotating shaft. The upper and lower walls of the arc-shaped cavity are embedded with bearings. The rotating shaft is connected to the inner ring of the bearing and can rotate around its own axis. The end of the rotating shaft located outside the arc-shaped cavity has an edge. An anti-rotation component adapted to the inner cavity of the end of the rotating shaft is detachably sleeved on the outside of the rotating shaft and detachably connected to the arc-shaped frame to restrict the rotation of the rotating shaft.

5. The simple hoisting device for large sand cores according to claim 4, characterized in that, The anti-rotation component is a bushing with a wide diameter section and a narrow diameter section. The narrow diameter section has an angular inner cavity, and the outer wall of the arc-shaped frame is provided with an annular embedding groove. The wide diameter section is interference-fitted into the annular embedding groove.

6. The simple hoisting device for large sand cores according to claim 1, characterized in that, The end of the long connecting rod is provided with a rotating connecting block. The rotating connecting block has a mounting hole in which two deep groove ball bearings are installed. The support shaft is connected to the deep groove ball bearings. One end of the support shaft is connected to the sand core clamping component, and the other end is connected to the handle.

7. The simple hoisting device for large sand cores according to claim 6, characterized in that, It also includes an anti-rotation frame, which is detachably connected to the handle and the long connecting rod.

8. The simple hoisting device for large sand cores according to claim 6, characterized in that, The shape of the sand core clamping component is adapted to the shape of the sand core overlap position and can be detachably connected to the support shaft.

9. The simple hoisting device for large sand cores according to claim 1, characterized in that, The long connecting rod includes an integrally formed short vertical section, a long vertical section, and an inclined section connecting the short vertical section and the long vertical section. The angle between the inclined section and the short vertical section and the long vertical section is 120°. The sand core clamping assembly is installed at the end of the long vertical section.

10. The simple hoisting device for large sand cores according to claim 1, characterized in that, One end of one of the two short connecting rods is equipped with a lifting section, and a lifting hole is provided on the lifting section.

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