A joint unit for supporting a mandrel of a pipe bending machine and a guide movable joint thereof

Abstract

The utility model discloses a kind of joint units for supporting core rod of bent pipe, comprising: at least two splicing bodies, each splicing body is sequentially spliced to form unit body, two ends are respectively inner embedded body and outer cover body, the surface of the inner wall of outer cover body is outer cover spherical surface, the surface of the circumferential outer edge of inner embedded body is inner embedded spherical surface, the end of inner embedded body away from outer cover body is located in inner embedded spherical surface and there is gap with inner embedded spherical surface, the spherical heart angle of outer cover body inner wall is greater than 180 °.The utility model further discloses a kind of guiding movable joint.The joint unit for supporting core rod of bent pipe and its guiding movable joint are formed in the unit body of at least two splicing bodies assembly, the end of its inner embedded body away from outer cover body is spaced with inner embedded spherical surface, after reducing the contact area of outer cover body and inner embedded body after the connection of adjacent two joint units, it is convenient to the relative movement between two joint units, and excessive wear is avoided.

Description

Technical Field

[0001] This utility model relates to the field of pipe bending technology, and in particular to a joint unit for supporting a mandrel in pipe bending and its guiding movable joint. Background Technology

[0002] In the pipe bending operation room, in order to prevent the pipe from bending and wrinkling, it is usually necessary to use a mandrel to support the inside of the metal pipe. When the pipe is pulled forward, due to the action of the mandrel, the material outside the center line of the pipe is stretched and hardened at the tangent point by the mandrel to maintain the shape of the pipe after bending.

[0003] In the prior art, such as the Chinese utility model with announcement number CN213968467U, a mandrel for connecting body and pipe bending is disclosed. The mandrel connecting body adopts matching sawtooth protrusions and sawtooth grooves to ensure uniform force after positioning and avoid misalignment, so that the mandrel connecting body fits better with the inner surface of the mandrel ball and mandrel.

[0004] However, in the aforementioned mandrel connector, the connector formed by splicing the first half-connector and the second half-connector has a spherical structure at one end. During assembly, the entire spherical surface contacts the inner wall of the second slot, increasing the contact area. This not only increases the amount of production material used and costs but also leads to increased wear. Furthermore, the wall thickness at the bottom of the second slot is small, resulting in low structural strength and making it prone to cracking and damage after repeated bending. In addition, the other end of the connector is flat, and the opening of the second slot is constricted, limiting the range of motion of the sphere after it is installed in the second slot. Moreover, the aforementioned connector needs to be assembled from the first half-connector and the second half-connector with different structures, meaning that the first half-connector and the second half-connector need to be produced simultaneously for assembly. Therefore, different molds are required, increasing production costs and reducing assembly efficiency.

[0005] Therefore, it is necessary to improve the connector of the bent tube support mandrel in the existing technology. Utility Model Content

[0006] The purpose of this invention is to overcome the defects in the existing technology and provide a joint unit and its guiding joint for supporting mandrels in bent tubes, which reduces the contact area to reduce wear, increases structural strength to reduce cracking, facilitates movement, reduces production costs, and improves assembly efficiency.

[0007] To solve the above-mentioned technical problems, this utility model discloses a joint unit for supporting a mandrel in a bent pipe, comprising:

[0008] At least two splicing bodies are sequentially spliced ​​to form a unit body, and matching positioning protrusions and positioning recesses are provided between adjacent splicing bodies. The two ends of the unit body are an inner body and an outer cover body, respectively. The curved surface of the inner wall of the outer cover body is an outer cover spherical surface, and the curved surface of the outer edge of the inner body is an inner cover spherical surface. The diameter of the outer cover spherical surface is the same as the diameter of the inner cover spherical surface. The end of the inner body away from the outer cover body is located inside the inner cover spherical surface and there is a gap between it and the inner cover spherical surface. The central angle of the inner wall of the outer cover body is greater than 180°.

[0009] Preferably, for ease of processing and production, the end of the inner body away from the outer cover is a flat surface, and the line connecting the center of the inner sphere and the center of the outer cover sphere is the unit center line of the unit body, which is perpendicular to the flat surface.

[0010] Preferably, in order to enhance the structure and prevent cracking, a reinforcing convex ring is integrally formed on the inner wall of the outer cover. The axis of the reinforcing convex ring coincides with the center line of the unit. The distance between the reinforcing convex ring and the center of the outer cover sphere is greater than the distance between the flat surface and the center of the embedded sphere.

[0011] Preferably, in order to further prevent structural damage to the outer cover, the reinforcing ring is disposed adjacent to the end of the outer cover that is adjacent to the inner body.

[0012] Preferably, to facilitate movement after assembly, the inner cavity of the outer cover has an flared shape from the inside out at the end opposite to the inner body.

[0013] Preferably, in order to reduce the number of splicing elements and lower production costs, two splicing elements are provided and arranged opposite each other, with the splicing surfaces of the two splicing elements located on the same plane.

[0014] Preferably, in order to avoid structural damage to the outer cover, the positioning protrusion and the positioning recess are provided on the inner body of the unit body.

[0015] Preferably, in order to ensure assembly accuracy, at least two of the positioning protrusions and the positioning recesses are provided, and they correspond one-to-one.

[0016] Preferably, in order to reduce production costs and facilitate rapid assembly, the two spliced ​​bodies have the same structure and the same size.

[0017] To solve the above-mentioned technical problems, this utility model also discloses a guide joint for a support mandrel in a bent pipe, including the joint unit described in any of the above technical solutions. Multiple joint units are provided and connected in sequence. In two adjacent joint units, the inner spherical surface of one coincides with the outer spherical surface of the other, and the inner body of one is movably connected to the outer body of the other.

[0018] In summary, compared with the prior art, the joint unit and its guiding movable joint of the present invention for the support mandrel of the bent pipe have a gap between the end of the inner body away from the outer cover and the inner spherical surface in the unit body formed by assembling at least two splicing bodies. This reduces the contact area between the outer cover and the inner body after the connection of two adjacent joint units, which not only facilitates the relative movement between the two joint units, but also avoids excessive wear. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the joint unit in the first embodiment;

[0020] Figure 2 yes Figure 1 An explosion diagram;

[0021] Figure 3 yes Figure 1 A schematic diagram of the cross-sectional structure;

[0022] Figure 4 yes Figure 3 The front view;

[0023] Figure 5 This is a schematic diagram of the guide joint based on the first embodiment;

[0024] Figure 6 yes Figure 5 Partial structural diagram;

[0025] Figure 7 yes Figure 6 Enlarged view of part A;

[0026] Figure 8 This is a schematic diagram of the joint unit in the second embodiment;

[0027] Figure 9 yes Figure 8 An explosion diagram;

[0028] Figure 10 yes Figure 8 An illustration of the explosion from another perspective;

[0029] Figure 11 This is a structural schematic diagram of the third embodiment;

[0030] Figure 12 yes Figure 11 An explosion diagram;

[0031] In the diagram: 1. Assembly body; 11. Positioning protrusion; 12. Positioning recess; 13. Semi-embedded body; 14. Semi-covered body; 15. Semi-convex ring; 2. Unit body; 21. Inset body; 211. Flat surface; 22. Outer cover body; 222. Reinforcing convex ring. Detailed Implementation

[0032] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0033] First Embodiment

[0034] like Figures 1-4 As shown, the joint unit for supporting the mandrel in a bent pipe according to the first embodiment of this utility model includes:

[0035] At least two splicing bodies 1 are sequentially spliced ​​to form a unit body 2, and a matching positioning protrusion 11 and positioning recess 12 are provided between adjacent splicing bodies 1. The two ends of the unit body 2 are an inner body 21 and an outer cover 22, respectively. The curved surface where the inner wall of the outer cover 22 is located is an outer cover spherical surface, and the curved surface where the outer edge of the inner body 21 is located is an inner cover spherical surface. The diameter of the outer cover spherical surface is the same as the diameter of the inner cover spherical surface. The end of the inner body 21 away from the outer cover 22 is located inside the inner cover spherical surface and there is a gap between it and the inner cover spherical surface. The central angle of the inner wall of the outer cover 22 is greater than 180°.

[0036] To facilitate quick assembly, the joint unit in this embodiment is formed by assembling two splicing bodies 1 to form a unit body 2. This reduces the number of splicing bodies 1 and improves the assembly efficiency of the unit body 2.

[0037] The unit 2, assembled from two splicing bodies 1, has an inner body 21 and an outer cover 22 at its two ends. When the two unit bodies 2 are connected, the inner body 21 of one unit body 2 can be inserted into the outer cover 22 of the other unit body 2. Since the inner spherical surface where the outer edge of the inner body 21 of the unit body 2 is located and the outer spherical surface where the inner wall of the outer cover 22 is located have the same diameter, the inner body 21 of one unit body 2 and the outer cover 22 of the other unit body 2 can rotate freely, facilitating the adjustment of the two unit bodies 2. In addition to the relative position, since there is a gap between the end face of the inner body 21 and its corresponding inner spherical surface, the contact area between the inner body 21 and the outer cover 22 is reduced. On the one hand, this reduces wear and facilitates the relative movement of the two unit bodies 2, thus making it easier to support the pipe by bending the mandrel during pipe bending operations. On the other hand, it reduces the production material of the inner body 21 and lowers the production cost. Since the spherical center angle of the inner wall of the outer cover 22 is greater than 180°, it ensures the movement space of the inner body 21 and prevents the inner body 21 from detaching from the outer cover 22.

[0038] Specifically, each of the two splicing bodies 1 includes an integrally connected semi-embedded body 13 and a semi-covered body 14. When the two splicing bodies 1 are spliced ​​and assembled, the two semi-embedded bodies 13 combine to form the inner body 21 of the unit body 2, and the two semi-covered bodies 14 combine to form the outer cover 22 of the unit body 2.

[0039] A further improvement is that the end of the inner body 21 away from the outer cover 22 is a flat surface 211, and the line connecting the center of the inner sphere and the center of the outer cover sphere is the unit center line of the unit body 2, which is perpendicular to the flat surface 211.

[0040] The above design facilitates the production and molding of the two splicing bodies 1. More specifically, the cross-section of the unit body 2 along the center line of the unit has two main shapes. At the position corresponding to the inner body 21, the cross-section of the unit body 2 is circular, and at the position corresponding to the outer cover 22, the cross-section of the unit body 2 is annular. The center of the circular cross-section and the annular cross-section are both located on the center line of the unit. In this way, it is ensured that after the two splicing bodies 1 are assembled to form the unit body 2, the force is uniform and consistent along the circumference of the unit body 2.

[0041] A further improvement is that a reinforcing ring 222 is integrally formed on the inner wall of the outer cover 22. The axis of the reinforcing ring 222 coincides with the center line of the unit. The distance between the reinforcing ring 222 and the center of the outer cover spherical surface is greater than the distance between the flat surface 211 and the center of the inner spherical surface. The reinforcing ring 222 is located adjacent to the end of the outer cover 22 and the inner body 21.

[0042] Specifically, on one side of the semi-cover 14, a semi-convex ring 15 is provided on the two splicing bodies 1. The semi-convex ring 15 is semi-circular in shape and is coaxial with the semi-cover 14 and the semi-embedded body 13. When the two splicing bodies 1 are spliced ​​together by the matching positioning recess 12 and positioning protrusion 11, the two semi-convex rings 15 are positioned opposite each other and connected end to end to form a circular reinforcing ring 222. The reinforcing ring 222 can increase the wall thickness at the adjacent ends of the outer cover 22 and the inner embedded body 21, thereby increasing the structural strength and preventing the joint unit from being subjected to excessive compressive stress after long-term use, which could lead to the risk of breakage at the relatively weak wall of the outer cover 22 due to excessive compressive stress.

[0043] A further improvement is that the end of the inner cavity of the outer cover 22 that faces away from the inner insert 21 is flared outwards.

[0044] This design increases the size of the opening of the outer cover 22, which facilitates the movement of the inner body 21 located in one of the outer covers 22 after the two unit bodies 2 are assembled. This increases the range of rotation and avoids excessive interference from the end face of the outer cover 22, thus limiting the relative rotation angle of the two unit bodies 2.

[0045] A further improvement is that there are two splicing bodies 1, which are positioned opposite each other, and the splicing surfaces of the two splicing bodies 1 are located on the same plane.

[0046] Compared to the serrated surface design, this design reduces the production difficulty of the splicing surfaces of the two splicing bodies 1, facilitates the mass production of splicing bodies 1, and improves the production efficiency of splicing bodies 1.

[0047] A further improvement is that the positioning protrusion 11 and the positioning recess 12 are set on the splicing surface of the two splicing bodies 1, that is, on the opposite surface of the two splicing bodies 1. More specifically, the positioning protrusion 11 and the positioning recess 12 are set on the inner body 21 of the unit body 2. In this way, the positioning recess 12 is not set on the outer cover 22, which would cause structural damage to the outer cover 22, reduce the structural strength of the outer cover 22, and make the outer cover 22 easy to break and be damaged.

[0048] A further improvement is that at least two positioning protrusions 11 and positioning recesses 12 are provided, and they correspond one-to-one.

[0049] Specifically, each of the two splicing bodies 1 is provided with a positioning protrusion 11 and a positioning recess 12, so that there are two positioning protrusions 11 and two positioning recesses 12 between the two splicing bodies 1, which increases the positioning contact area, enhances the positioning accuracy, and ensures the splicing accuracy of the two splicing bodies 1.

[0050] More specifically, both the positioning protrusion 11 and the positioning recess 12 are elongated strips. They are arranged side by side and adjacent to each other along the length of the unit center line and extend along the length direction perpendicular to the unit center line. The positioning protrusion 11 is a positioning protrusion, and the positioning recess 12 is a positioning through groove. Both ends of the positioning protrusion and the positioning groove extend to the end of the semi-embedded body 13.

[0051] like Figures 5-7 As shown, the guide joint based on this embodiment includes the joint unit mentioned above. Multiple joint units are provided and connected in sequence. In two adjacent joint units, the inner spherical surface of one coincides with the outer spherical surface of the other, and the inner body 21 of one is movably connected to the outer body 22 of the other.

[0052] With the above structure, multiple joint units are connected in sequence, allowing one of the inner bodies 21 of two adjacent unit bodies 2 to move within the outer body 22 of another, facilitating the rotational connection between the two adjacent joint units. In the two adjacent joint units, there is a gap between the flat surface 211 of the inner body 21 and the inner wall of the outer body 22, reducing the contact area, reducing wear, and reducing the amount of production materials used, thus lowering costs. Moreover, a reinforcing protrusion 222 is provided on the inner wall of the outer body 22, increasing the structural strength of the outer body 22 and preventing it from easily breaking after repeated bending. The reinforcing protrusion 222 is adjacent to the inner bottom wall of the outer body 22, which helps to increase the movement space of the inner body 21. Furthermore, the opening of the outer body 22 adopts an flared shape from the inside out, increasing the movement space of the inner body 21 and facilitating the relative rotational connection between the two unit bodies 2.

[0053] For example Figure 5 The joint unit shown only requires fixing two splice bodies 1 to the right side of the figure, for example, by binding the two splice bodies 1 tightly with steel wire rope, and then fixing the two splice bodies 1 in the other unit bodies 2.

[0054] Second Embodiment

[0055] like Figures 8-10 As shown, the joint unit for supporting the mandrel in the bending pipe of the second embodiment of this utility model is based on the first embodiment, except that the two splicing bodies 1 have the same structure and the same size.

[0056] With the above structure, only one set of molds is needed to produce a batch of spliced ​​bodies 1 with the same structure and size. Any two of them can be selected for assembly to form a unit body 2. Compared with the first embodiment, where the two spliced ​​bodies 1 have different structures and require at least two sets of molds to produce and two spliced ​​bodies 1 with specific shapes to be selected for assembly, the technical solution of this embodiment can reduce the number of production molds to reduce costs, while facilitating rapid assembly.

[0057] Specifically, in the two splicing bodies 1, the positioning protrusion 11 and the positioning recess 12 are coaxial, with the same length, cross-sectional shape and size, and they intersect at the center of the sphere of the semi-embedded body 13. This makes the two splicing bodies 1 have the same shape and size, which facilitates the use of the same mold for production, thereby reducing production costs and improving assembly efficiency.

[0058] Third Embodiment

[0059] like Figures 8-10As shown, the joint unit for supporting the mandrel in the bending pipe of the third embodiment of this utility model is based on the second embodiment, but the difference is that three pairs of splicing units are provided on the splicing surface of the semi-embedded body 13 of the splicing body 1, which are distributed along the center line of the unit. The splicing unit includes positioning protrusions 11 and positioning recesses 12 that are in the same length direction and are adapted to each other. The positioning protrusions 11 and positioning recesses 12 intersect on the center line of the unit.

[0060] By adopting the above structure, the number of positioning protrusions 11 and positioning recesses 12 is increased, which helps to increase the positioning accuracy of the two splicing bodies 1 and ensure the connection accuracy between the unit bodies 2, so as to achieve good support for the mandrel and thus improve the quality of pipe bending.

[0061] 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 technical principles 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 joint unit for supporting a mandrel in a bent pipe, characterized in that, include: At least two splicing bodies are sequentially spliced ​​to form a unit body, and matching positioning protrusions and positioning recesses are provided between adjacent splicing bodies. The two ends of the unit body are an inner body and an outer cover body, respectively. The curved surface of the inner wall of the outer cover body is an outer cover spherical surface, and the curved surface of the outer edge of the inner body is an inner cover spherical surface. The diameter of the outer cover spherical surface is the same as the diameter of the inner cover spherical surface. The end of the inner body away from the outer cover body is located inside the inner cover spherical surface and there is a gap between it and the inner cover spherical surface. The central angle of the inner wall of the outer cover body is greater than 180°.

2. The joint unit for supporting a mandrel in a bent pipe according to claim 1, characterized in that: The end of the inlay away from the outer cover is a flat surface. The line connecting the center of the inlay sphere and the center of the outer cover sphere is the unit center line of the unit, and the unit center line is perpendicular to the flat surface.

3. The joint unit for supporting a mandrel in a bent pipe according to claim 2, characterized in that: A reinforcing ring is integrally formed on the inner wall of the outer cover. The axis of the reinforcing ring coincides with the center line of the unit. The distance between the reinforcing ring and the center of the outer cover sphere is greater than the distance between the flat surface and the center of the inner sphere.

4. The joint unit for supporting a mandrel in a bent pipe according to claim 3, characterized in that: The reinforcing convex ring is disposed adjacent to the end of the outer cover body that is adjacent to the inner body.

5. The joint unit for supporting a mandrel in a bent pipe according to claim 1, characterized in that: The inner cavity of the outer cover has an flared shape at one end opposite to the inner body, extending from the inside out.

6. The joint unit for supporting a mandrel in a bent pipe according to claim 1, characterized in that: The splicing body is provided in two parts and is positioned opposite each other, with the splicing surfaces of the two splicing bodies located on the same plane.

7. The joint unit for supporting a mandrel in a bent pipe according to claim 6, characterized in that: The positioning protrusion and the positioning recess are disposed on the inner body of the unit body.

8. The joint unit for supporting a mandrel in a bent pipe according to claim 7, characterized in that: The positioning protrusions and positioning recesses are provided in at least two and correspond one-to-one.

9. The joint unit for supporting a mandrel in a bent pipe according to claim 7, characterized in that: The two spliced ​​bodies have the same structure and the same size.

10. A guide joint for supporting a mandrel in a bent pipe, characterized in that: The joint unit includes any one of claims 1-9, wherein multiple joint units are provided and connected in sequence, wherein in two adjacent joint units, the inner spherical surface of one coincides with the outer spherical surface of the other, and the inner body of one is movably connected to the outer body of the other.

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