A reusable wire laying core mold for bent pipe components

Abstract

The present invention discloses a reusable core mold for laying wire for a bent pipe component. It comprises a curved section module, a straight section module, a fixed end and a connecting rod; a plurality of curved section modules and a plurality of straight section modules are connected by connecting rods to form a core mold for laying wire for a bent pipe component whose central axis has certain curve characteristics; both ends are connected to the laying wire equipment through fixed ends to complete the laying wire process; during demoulding, by applying a pulling force on one side of the fixed end, the connecting rod of each module drives the upper and lower support blocks to overcome the elastic force of the spring and shrink inward to the notches of the left and right support blocks; the tension spring acts on the left and right support blocks to shrink inward, making the cross-sectional area of ​​each module smaller, while the spacing between each module becomes larger; each module can rotate around the hinged support connected thereto, making the core mold as a whole flexible and convenient to be pulled out from the formed bent pipe component. The present invention can be used as a core mold in the laying wire process of a bent pipe component, is convenient for demoulding and is reusable, and can reduce the cost of laying wire for a bent pipe component and improve efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic wire placement of composite materials, and in particular relates to a reusable wire placement core die for a bent pipe component. Background Art

[0002] Composite materials are widely used in the aerospace field. As an advanced composite material forming technology, automatic wire placement technology has become the mainstream manufacturing technology for complex components such as high-performance composite rotating bodies. A large number of curved tube components are required in aerospace. The wire placement manufacturing technology of composite curved tube components represented by carbon fiber and fiberglass mainly uses CNC wire placement equipment to plan and design the direction of the fiber bundle on the contour surface of the core mold according to the shape of the core mold to complete the automatic wire placement process. After curing and demolding, the curved tube component with a shape completely consistent with the outer contour of the core mold is obtained. In this process, the core mold plays a supporting and fixing role and needs to be pulled out from the curved component after the placement is completed. Therefore, the core mold must have a certain degree of rigidity and has high requirements for size and shape. The core mold structure directly affects the component wire placement molding and demolding process.

[0003] The bent pipe component is a quasi-rotational component with a uniform cross-section and a central axis having a certain curvilinear feature. It is usually composed of several straight segments and several curved segments. Due to the complex shape and structure of the pipe and the certain rigidity of the mold, demolding is relatively difficult. Although the cross-sectional shape is consistent between the straight segments and the curved segments of the bent component or between curved segments with different curvatures, the mold has a certain thickness in the direction of the central axis of the pipe. Since the axis of the mold module between different pipe segments does not coincide with the axis of the pipe, there is interference with the bent pipe component during the demolding process, so it is difficult to demold a reusable mold. At present, the preparation process of the bent pipe component is completed using a non-reusable disposable core mold. The disposable core mold is usually made of a soluble or breakable material, which is dissolved or broken after the wire laying is completed. The preparation process is complicated, non-reusable, inefficient and costly. Summary of the Invention

[0004] In order to solve the problems in the background technology, the present invention discloses a reusable core mold for wire laying of curved pipe components, which effectively solves the problems of low efficiency, high cost and difficulty in demolding the reusable core mold caused by the non-reusability of the mold in the existing wire laying process of curved pipe components. The core mold provides support and fixing in the wire laying manufacturing process of circular cross-section curved pipe components, can be smoothly removed during the demolding process, and can automatically reset and be reused after being removed, thereby reducing the wire laying manufacturing cost of curved pipe components and improving production efficiency.

[0005] The technical solution adopted in the present invention is as follows:

[0006] 1. A reusable wire-laying mandrel for bent pipe components

[0007] It includes a core mold main part and a core mold fixed end. Multiple curved segments and multiple straight segments are connected to form a core mold main part with a circular cross-section and a specific curved axis. The main part is connected to fixed ends at both ends; each curved segment is composed of multiple curved segment modules, and each straight segment is composed of multiple straight segment modules. Adjacent modules are hinged by connecting rods.

[0008] Both the curved section module and the straight section module are composed of two upper and lower support blocks A, two left and right support blocks B, a fixed bracket, a tension spring and a spring; the fixed bracket is cross-shaped, with rectangular grooves in the upper and lower directions and a rectangular through-hole in the horizontal direction; the outer sides of the upper and lower support blocks A and the left and right support blocks B are both curved surfaces, and the inner sides are provided with rectangular slider ends; the rectangular slider ends of the upper and lower support blocks A are slidably installed in the upper and lower rectangular grooves of the fixed bracket through springs, and one end of the spring located in the rectangular groove is fixedly connected to the support block A, and the other end is fixedly connected to the bottom of the rectangular groove; a tension spring is provided in the rectangular through-hole of the fixed bracket, and the rectangular slider ends of the left and right support blocks B are extended into the rectangular through-hole and fixedly connected to the two ends of the tension spring respectively, and the rectangular slider ends of the left and right support blocks B are clearance-matched with the rectangular through-hole and can slide in the rectangular through-hole.

[0009] The rectangular slider end and the rectangular slot opening of support block A are both equipped with flanges to prevent the slider end of support block A from falling out of the rectangular slot. Rectangular slots in the upper and lower directions are used to constrain the movement of the upper and lower support blocks A, and rectangular through holes in the horizontal direction are used to constrain the movement of the left and right support blocks B.

[0010] There are two upper and lower notches on the inner sides of the two support blocks B. The notches of the left and right support blocks B are symmetrically arranged to form two pairs of upper and lower notches. The shapes of the upper and lower pairs of notches are respectively adapted to the left and right ends of the two support blocks A. When the core mold is subjected to axial tension, the upper and lower support blocks A overcome the spring force and shrink inward at the same time. When the two support blocks A move to the notches of the two support blocks B, the supporting effect of the two support blocks A on the two support blocks B disappears. The left and right support blocks B shrink inward instantly under the action of the tension of the tension spring, so that the left and right ends of the two support blocks A are embedded in the upper and lower pairs of notches of the two support blocks B, and the cross-sectional area of ​​the entire module becomes smaller.

[0011] When the core mold is not subjected to axial tension, the curved section module or the straight section module is in a naturally expanded state, and the spring expands the upper and lower support blocks A outward through the outward expansion force, and the tension spring makes the left and right support blocks B close to the left and right sides of the upper and lower support blocks A through the inward contraction force; the arc surfaces of the outer sides of the upper and lower support blocks A and the left and right support blocks B are connected to form a support body with an outer contour cross-section that is a complete circle; along the axis direction of the core mold, the straight section module is a straight cylindrical structure with the same width at the top and bottom, and the curved section module is a curved cylindrical structure that is wide at the top and narrow at the bottom or narrow at the top and wide at the bottom, and multiple curved section modules form a curved section.

[0012] An articulated support is provided on the front side or rear side of the fixed bracket, and an articulated support is provided on the inner side of the upper and lower support blocks A. The articulated support of the support block A and the articulated support of the fixed bracket are located on different sides; the two adjacent curved section modules, the two straight section modules, and the curved section module and the straight section module are connected by two connecting rods, one end of the two connecting rods is respectively hinged to the upper and lower support blocks A of the curved section module or the straight section module, and the other end of the two connecting rods is hinged to the fixed bracket of the adjacent curved section module or the straight section module.

[0013] After being pulled apart, each module can rotate around the hinged support of the fixed bracket, and the central axis of the core mold body becomes flexible and variable, so that the core mold can be drawn out from the formed bent pipe component.

[0014] The curved or straight segment modules of the core mold are in their naturally expanded state, with adjacent modules tightly attached. The connecting rod length between the modules is designed to ensure that the curved outer surfaces of the upper and lower support blocks A and the left and right support blocks B meet to form a perfectly circular cross-section. The distances between the hinged joints of adjacent curved modules, between two straight modules, and between a curved module and a straight module vary.

[0015] During wire laying, the core mold is fixed to the fixed base of the automatic wire laying equipment through the two fixed ends;

[0016] During demoulding, the two fixed ends of the core mold are removed from the fixed seat of the automatic wire laying equipment, and then one of the fixed ends is connected to the demoulding equipment, and the demoulding equipment applies a pulling force to pull the core mold out of the bent pipe component.

[0017] 2. Working method of a reusable wire-laying mandrel for bent pipe components

[0018] The following steps are involved:

[0019] 1) In the initial state of the core mold, the two adjacent modules are tightly attached to each other; the two fixed ends of the core mold are fixed to the fixed base of the automatic wire laying equipment, and the wire is laid on the automatic wire laying equipment according to the shape of the core mold to complete the preparation of the bent pipe component; during the wire laying process, there is no relative movement between the modules and the shape of the core mold does not change.

[0020] The module is either a curved segment module or a straight segment module.

[0021] 2) During the demoulding process, one fixed end of the core mold is connected to the demoulding mechanism of the demoulding device, and the other fixed end is disconnected from the core mold, and an axial tension is applied to one of the fixed ends by the demoulding device;

[0022] Under the action of tension, the two connecting rods cause the upper and lower support blocks A to simultaneously overcome the elastic force of the springs and retract inward. At the same time, the angle between the two connecting rods becomes smaller, and the spacing between adjacent modules becomes larger. Each module rotates around the hinge seat on the fixed bracket of the previous module connected to the connecting rod. When the upper and lower support blocks A retract inward to the grooves of the left and right support blocks B on both sides, the left and right support blocks B retract inward at the same time under the action of the tension springs, and the two support blocks A are stuck in the grooves of the two support blocks B. The tension is transmitted between the straight section module and the curved section module through the connecting rod and the fixed bracket. The four support blocks in each module retract inward to reduce the cross-sectional area, so that each module does not interfere with the inner wall of the formed curved pipe when it is withdrawn, facilitating demoulding and withdrawal of the core mold.

[0023] 3) After demoulding is completed and the core mold is completely pulled out, the axial tension at one end of the core mold disappears, and the upper and lower support blocks A in each module are reset under the action of the spring force. The left and right support blocks B are stretched open and restored to their original state under the drive of the upper and lower support blocks A, and are tightly attached to the left and right sides of the support block A under the tension of the tension spring. The angle between the two connecting rods becomes larger, and the distance between each module becomes smaller until it is close to each other, and the reset is completed.

[0024] Beneficial effects of the present invention:

[0025] 1) The present invention can reduce the cross-sectional area of ​​each module by shrinking the upper and lower support blocks and the left and right support blocks in each module toward the center without interfering with each other, thereby reducing the core mold module of the rigid body, and ensuring that the core mold does not interfere with the bending member during the demolding process and can be smoothly ejected.

[0026] 2) Each module of the present invention is connected together by a hinge, so that the overall structure of the core mold has a certain flexibility, and each module of the core mold can be pulled out from the curved pipe component with a formed complex central axis.

[0027] 3) The core mold of the present invention can automatically reset after being completely pulled out during the demoulding process and return to its original core mold shape, so as to achieve reuse, reduce production costs, simplify operation, and improve the efficiency of the mold preparation process.

[0028] 4) The present invention can form a core mold of a central axis bent pipe member with different curve characteristics or a bent member with other rotational cross-sectional shapes by changing the shape and size of each module and the combination method between the modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the overall structure of the present invention in its natural state;

[0030] Figure 2 This is a schematic diagram of the overall structure under tension during the demoulding process of the present invention;

[0031] Figure 3This is a schematic structural diagram of a straight segment module or a curved segment module of the present invention;

[0032] Figure 4 A cross-sectional view of the straight segment module or curved segment module structure of the present invention;

[0033] Figure 5 This is a schematic diagram of the external shape of the straight segment module of the present invention;

[0034] Figure 6 This is a schematic diagram of the external shape of the bending section module of the present invention;

[0035] Figure 7 This is a schematic diagram of the contraction of the straight segment module or the curved segment module when subjected to tension during the demoulding process of the present invention.

[0036] In the figure: 1. curved section, 2. straight section, 3. connecting fixed end, 4. curved section module, 5. straight section module, 6. connecting rod, 7. support block A, 8. support block B, 9. fixed bracket, 10. tension spring, 11. spring. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] like Figure 1 As shown, the main part of the core mold of the present invention is composed of a plurality of curved segments 1 and a plurality of straight segments 2. According to actual manufacturing requirements, a plurality of curved segments 1 and a plurality of straight segments 2 constitute the main part of the core mold with a central axis having different curve characteristics. Both the head and tail sides of the main part are connected to the connecting fixed ends 3. During the wire laying process, the head and tail connecting fixed ends 3 are fixedly connected to the fixed seat of the automatic wire laying equipment. During the demolding process, one of the connecting fixed ends 3 is connected to the demolding mechanism of the demolding equipment. The main part of the core mold is pulled out by applying a pulling force in the axial direction of the connecting fixed end 3.

[0039] like Figure 2 As shown, each curved segment 1 is composed of a plurality of curved segment modules 4 , and each straight segment 2 is composed of a plurality of straight segment modules 5 , and each module is connected by a connecting rod 6 .

[0040] like Figure 3 As shown, the curved segment module 4 and the straight segment module 5 are composed of two upper and lower support blocks A7 and two left and right support blocks B8, a fixed bracket 9, a tension spring 10 and a spring 11. The fixed bracket 9 is cross-shaped, with rectangular grooves in the upper and lower directions to constrain the movement of the upper and lower support blocks A7, and rectangular through holes in the horizontal direction to constrain the movement of the left and right support blocks B8, as shown in FIG. Figure 4As shown, the rectangular slider ends of the upper and lower support blocks A7 are loosely coupled with the rectangular slots of the fixed bracket 9, allowing the support blocks A7 to slide within the slots. One end of a spring 11 is fixedly connected to the support block A7, and the other end is fixedly connected to the bottom of the rectangular slot of the fixed bracket 9. In a natural state, the upper and lower support blocks A7 are stretched apart by the elastic force of the spring 11. The rectangular slider ends of the left and right support blocks B8 are loosely coupled with the rectangular through-holes of the fixed bracket 9, allowing the support blocks B8 to slide within the through-holes. The ends of the tension spring 10 are respectively fixedly connected to the bottom of the rectangular slider ends of the support blocks B8. Under the tension of the tension spring 10, the left and right support blocks B8 are tightly attached to the sides of the upper and lower support blocks. The support blocks B8 have notches that mate with the sides of the upper and lower support blocks A7. When the upper and lower support blocks A7 simultaneously retract inward, overcoming the elastic force of the spring 11, the left and right sides of the support blocks A7 are clamped by the notches of the two support blocks B8 under the tension of the tension spring 10. Under the combined action of the spring 11 and the fixed bracket 9 on the upper and lower support blocks A7 and the tension spring 10 on the left and right support blocks B8, the outer contour cross section of the support body formed by the four support blocks is a complete circle. Figure 5 As shown, the outer surfaces of the upper and lower support blocks A7 and the left and right support blocks B8 of the straight segment module 5 are in the shape of straight cylinders. Figure 6 As shown, the outer surfaces of the upper and lower support blocks A7 and the left and right support blocks B8 of the bending section module 4 are curved cylindrical.

[0041] like Figure 2 As shown, the support block A7 and the fixed bracket 9 are both provided with hinged supports. The curved section modules 4, the straight section modules 5, and the curved section modules 4 and the straight section modules 5 are connected by two connecting rods 6, wherein one end of the two connecting rods 6 is hinged to the upper support block or the lower support block of the curved section module 4 or the straight section module 5, and the other end is hinged to the fixed bracket 9 of the adjacent curved section module 4 or the straight section module 5. After being pulled apart, each module can rotate around the hinged support of the fixed bracket 9, and the central axis of the core mold body becomes flexible and variable, so that the core mold can be pulled out of the formed curved pipe component. The length of the connecting rod 6 is determined by the distance between the hinged seats connecting the curved section modules 4, the straight section modules 5, and the curved section modules 4 and the straight section modules 5 when the core mold support blocks are naturally expanded, ensuring that there is no gap between the modules. Specific embodiment:

[0043] 1) The core mold is in the initial state. Figure 1 The central axis shown has a curved component shape with certain curve characteristics. It is installed on the automatic wire laying equipment through the connection fixed end 3 to perform the wire laying process. During the wire laying process, there is no relative movement between the various parts and the shape of the core mold will not change.

[0044] 2) During the demoulding process, the two connecting fixed ends 3 are connected to the demoulding mechanism of the demoulding equipment, one of the connecting fixed ends 3 is disconnected from the core mold, and a pulling force is applied to the axial direction of the other connecting fixed end 3, such as Figure 2 and Figure 7 As shown, under the action of tension, the two connecting rods 6 cause the upper and lower support blocks A7 to simultaneously overcome the elastic force of the spring 11 and retract inward. At the same time, the angle between the two connecting rods 6 becomes smaller, and the spacing between adjacent modules becomes larger. Each module can rotate around the hinge seat on the fixed bracket 9 of the previous module connected to the connecting rod 6. When the upper and lower support blocks A7 retract inward to the grooves of the left and right support blocks B8 on both sides, the left and right support blocks B8 retract inward at the same time under the action of the tension spring 10, and the two support blocks A7 are stuck in the grooves of the two support blocks B8. The tension is transmitted between the straight section module 5 and the curved section module 4 through the connecting rod 6 and the fixed bracket 9. The four support blocks in each module retract inward to reduce the cross-sectional area, so that each module does not interfere with the inner wall of the formed curved pipe when it is pulled out, so that the core mold can be demolded and pulled out.

[0045] 3) After demoulding is completed and the core mold is completely pulled out, the axial tension at one end of the core mold disappears, and the upper and lower support blocks A7 in each module are reset under the elastic force of the spring 11. The left and right support blocks B8 are stretched apart by the upper and lower support blocks A7 and restored to their original positions. Under the tension of the tension spring 10, they are tightly attached to the left and right sides of the support block A7. The angle between the two connecting rods 6 becomes larger, and the distance between each module becomes smaller until they are tightly attached, and the reset is completed.

Claims

1. A reusable wire-laying mandrel for a bent pipe component, characterized in that: The invention comprises a core mold main body and a core mold fixed end (3), a plurality of curved segments (1) and a plurality of straight segments (2) connected to form a core mold main body with a circular cross section and a curved axis, and the fixed ends (3) are connected to the head and tail ends of the main body respectively; each curved segment (1) is composed of a plurality of curved segment modules (4), and each straight segment (2) is composed of a plurality of straight segment modules (5), and two adjacent modules are hinged by a connecting rod (6); The curved segment module (4) and the straight segment module (5) are both composed of two upper and lower support blocks A (7), two left and right support blocks B (8), a fixed bracket (9), a tension spring (10) and a spring (11); The fixing bracket (9) is cross-shaped, has rectangular grooves in both the upper and lower directions, and has rectangular through holes in the horizontal direction; The outer side surfaces of the upper and lower support blocks A (7) and the left and right support blocks B (8) are all arc surfaces, and the inner side surfaces are all provided with rectangular slider ends; the rectangular slider ends of the upper and lower support blocks A (7) are slidably installed in the upper and lower rectangular grooves of the fixed bracket (9) through springs (11), one end of the spring (11) located in the rectangular groove is fixedly connected to the support block A (7), and the other end is fixedly connected to the bottom of the rectangular groove; a tension spring (10) is provided in the rectangular through hole of the fixed bracket (9), and the rectangular slider ends of the left and right support blocks B (8) are respectively fixedly connected to the two ends of the tension spring (10) after extending into the rectangular through hole, and the rectangular slider ends of the left and right support blocks B (8) are clearance-matched with the rectangular through hole and can slide in the rectangular through hole; A hinged support is provided on the front side or rear side of the fixed bracket (9), and a hinged support is provided on the inner side of the upper and lower support blocks A (7), and the hinged support of the support block A (7) and the hinged support of the fixed bracket (9) are located on different sides; Two adjacent curved segment modules (4), two straight segment modules (5), and a curved segment module (4) and a straight segment module (5) are connected via two connecting rods (6), one end of each of the two connecting rods (6) being hinged to the upper and lower support blocks A (7) of the curved segment module (4) or the straight segment module (5), and the other end of each of the two connecting rods (6) being hinged to the fixed bracket (9) of the adjacent curved segment module (4) or the straight segment module (5).

2. A reusable wire-laying mandrel for a bent pipe component according to claim 1, characterized in that: The end of the rectangular slider of the support block A (7) and the opening of the rectangular groove are both provided with flanges to prevent the rectangular slider of the support block A (7) from falling out of the rectangular groove.

3. The reusable wire-laying mandrel for a bent pipe member according to claim 1, characterized in that: The inner side surfaces of the two support blocks B (8) are provided with two upper and lower notches. The notches of the left and right support blocks B (8) are symmetrically arranged to form two pairs of upper and lower notches. The shapes of the upper and lower pairs of notches are respectively adapted to the left and right ends of the two support blocks A (7); When the core mold is subjected to axial tension, the upper and lower support blocks A (7) overcome the elastic force of the spring (11) and shrink inward at the same time. When the two support blocks A (7) move to the notches of the two support blocks B (8), the supporting effect of the two support blocks A (7) on the two support blocks B (8) disappears. The left and right support blocks B (8) shrink inward instantly under the tension of the tension spring (10), so that the left and right ends of the two support blocks A (7) are embedded in the upper and lower pairs of notches of the two support blocks B (8), and the cross-sectional area of ​​the entire module becomes smaller.

4. The reusable wire-laying mandrel for a bent pipe component according to claim 1, characterized in that: When the core mold is not subjected to axial tension, the curved segment module (4) or the straight segment module (5) is in a naturally expanded state, the spring (11) expands the upper and lower support blocks A (7) outwards by the outward expansion elastic force, and the tension spring (10) causes the left and right support blocks B (8) to cling to the left and right side surfaces of the upper and lower support blocks A (7) by the inward contraction tension; the arc surfaces of the outer side surfaces of the upper and lower support blocks A (7) and the left and right support blocks B (8) are connected to form a support body with an outer contour cross section that is a complete circle; Along the core mold axis, the straight section module (5) is a straight cylindrical structure with the same width at the top and bottom, and the curved section module (4) is a curved cylindrical structure with a wide top and a narrow bottom or a narrow top and a wide bottom. A plurality of curved section modules (4) form a curved section.

5. The reusable wire-laying mandrel for a bent pipe component according to claim 1, characterized in that: The curved section module (4) or the straight section module (5) of the core mold is in a naturally expanded state, and the adjacent modules are tightly attached. The length of the connecting rod (6) between the adjacent modules is designed to ensure that the arc surfaces of the outer side surfaces of the upper and lower support blocks A (7) and the left and right support blocks B (8) are connected to form an outer contour cross-section that is a complete circle.

6. The reusable wire-laying mandrel for a bent pipe component according to claim 1, characterized in that: When laying the wire, the core mold is fixedly connected to the fixed seat of the automatic wire laying equipment through the two fixed ends (3) at the head and tail; During demoulding, the two fixed ends of the core mold are removed from the fixed seat of the automatic wire laying equipment, and then one of the fixed ends is connected to the demoulding equipment, and the demoulding equipment applies a pulling force to pull the core mold out of the bent pipe component.

7. The operating method of the reusable wire-laying mandrel for a bent pipe member according to claim 1, characterized in that: The following steps are involved: 1) In the initial state of the core mold, the two adjacent modules are tightly attached to each other; the two fixed ends (3) of the core mold are fixed to the fixed base of the automatic wire laying equipment, and the wire is laid on the automatic wire laying equipment according to the shape of the core mold to complete the preparation of the bent pipe component; during the wire laying process, there is no relative movement between the modules, and the shape of the core mold does not change; 2) During the demoulding process, one of the fixed ends (3) of the core mold is connected to the demoulding mechanism of the demoulding device, and the other fixed end (3) is disconnected from the core mold, and an axial pulling force is applied to one of the fixed ends (3) by the demoulding device; Under the action of tension, the two connecting rods (6) cause the upper and lower support blocks A (7) to simultaneously overcome the elastic force of the spring (11) and retract inwards, and at the same time, the angle between the two connecting rods (6) becomes smaller, and the distance between the two adjacent modules becomes larger, and each module rotates around the hinge seat on the fixed bracket (9) of the previous module connected to the connecting rod (6); when the upper and lower support blocks A (7) retract inwards to the grooves of the left and right support blocks B (8) on both sides, the left and right support blocks B (8) retract inwards at the same time under the action of the tension spring (10), and the two support blocks A (7) are stuck in the grooves of the two support blocks B (8); the tension is transmitted between the straight section module (5) and the curved section module (4) through the connecting rod (6) and the fixed bracket (9), and the four support blocks in each module retract inwards to reduce the cross-sectional area, so that each module does not interfere with the inner wall of the formed curved pipe when it is withdrawn, so that the core mold can be demoulded and withdrawn; 3) After demoulding is completed and the core mold is completely pulled out, the axial tension at one end of the core mold disappears, and the upper and lower support blocks A (7) in each module are reset under the elastic force of the spring (11). The left and right support blocks B (8) are stretched open and restored to their original state under the drive of the upper and lower support blocks A (7), and are tightly attached to the left and right sides of the support block A (7) under the tension of the tension spring (10). The angle between the two connecting rods (6) becomes larger, and the distance between each module becomes smaller until they are tightly attached, and the reset is completed.

Images