Die tip and expander for heat shrink tube expansion

Abstract

The utility model provides a die nozzle and expansion machine for heat shrink tube expansion. The die nozzle for heat shrink tube expansion includes seat mould and cover mould. Seat mould includes seat mould cavity, seat mould cavity passes through seat mould to have seat mould cavity mouth, seat mould cavity mouth links seat mould cavity's inside and seat mould's outside, the length of seat mould cavity mouth is equal to seat mould cavity's length that passes through seat mould. Cover mould includes cover mould cavity, cover mould cavity passes through cover mould to have cover mould cavity mouth, cover mould cavity mouth links cover mould cavity's inside and cover mould's outside, the length of cover mould cavity mouth is equal to cover mould cavity's length that passes through cover mould. Cover mould and seat mould cover, seat mould cavity mouth and cover mould cavity mouth butt joint, to make seat mould cavity and cover mould cavity surround the die cavity that heat shrink tube passes along seat mould's through -going direction. Thus, the above -mentioned die nozzle is simple structure, and the split type die nozzle of convenient dismounting can effectively reduce manual operation time, thereby realizing manual cost reduction and improving production efficiency.

Description

Technical Field

[0001] This utility model relates to equipment for tube forming, and further to a die and expansion machine for expanding heat shrink tubing. Background Technology

[0002] Heat shrink tubing is a type of tube made of shape-memory polymer material that can shrink upon heating. It is widely used in the automotive, power engineering, electronics manufacturing, and aerospace industries for insulation and protection of wire harnesses such as cables, signal cables, power cables, and ground wires, bringing great convenience to people's lives and promoting technological progress. A die is a mold used to pre-form semi-finished heat shrink tubing. Its functions are twofold: firstly, to ensure a smoother connection between the heating device and the vacuum expansion device; and secondly, to solve the problem of excessive expansion friction and tube stacking when the heated semi-finished heat shrink tubing directly enters the vacuum expansion device. Therefore, the die plays a crucial role in heat shrink tubing production.

[0003] However, the conventional nozzles commonly used in existing technologies are designed as a single unit. During the production process, when it is necessary to adjust the machine or switch to different specifications of semi-finished products, the nozzles need to be changed frequently. Since the stroke of the expansion equipment is several meters long, the tube needs to be cut and pulled out when disassembling the conventional nozzle. When the equipment is turned on, the cut tube needs to be connected with tape. The whole process is cumbersome, time-consuming and labor-intensive, increasing manual labor time and affecting production efficiency. Utility Model Content

[0004] To address the aforementioned technical problems, the purpose of this utility model is to provide a die and an expansion machine for expanding heat shrink tubing. The die for expanding heat shrink tubing is easy to replace, and the replacement process does not require cutting, pulling out, or reconnecting the tubing.

[0005] To achieve the above objectives, this utility model provides a nozzle for expanding heat shrink tubing. The nozzle for expanding heat shrink tubing includes a base mold and a cover mold. The base mold includes a mold cavity extending through it, and the mold cavity forms a mold cavity opening on the base mold, the mold cavity opening communicating between the interior of the mold cavity and the exterior of the base mold. The cover mold includes a mold cavity extending through it, and the mold cavity forms a mold cavity opening on the cover mold, the mold cavity opening communicating between the interior of the mold cavity and the exterior of the cover mold. The cover mold and the base mold are closed, and the mold cavity opening and the cover mold cavity opening are mated, such that the base mold cavity and the cover mold cavity form a mold cavity through which the heat shrink tubing passes along the through direction of the base mold.

[0006] In some embodiments, the mold seat cavity and the mold cover cavity are axially symmetrical.

[0007] In some embodiments, the cover mold and the base mold each include a first side and a second side opposite to each other; the first side of the cover mold and the first side of the base mold are rotatably connected; the second side of the cover mold and the second side of the base mold are detachably connected; and when the second side is detached, the cover mold can be flipped relative to the base mold.

[0008] In some embodiments, both the second side of the cover mold and the second side of the base mold include through holes, and the nozzle includes a bolt and a nut, the bolt passing through the through hole and being locked by the nut; or, one of the second side of the cover mold and the second side of the base mold is provided with a through hole, and the other is provided with a threaded hole, the nozzle for expanding the heat shrink tubing includes a bolt, the bolt passing through the through hole and connected to the threaded hole; or, the second side of the cover mold and the second side of the base mold are locked together by a snap-fit ​​structure.

[0009] In some embodiments, the base mold and the cover mold are assembled by a mortise and tenon structure and locked by a limiting structure that prevents relative movement between the tenon and mortise of the mortise and tenon structure.

[0010] In some embodiments, one of the cover mold and the base mold is provided with a protrusion, and the other is provided with a groove; both the groove and the protrusion extend along the through direction of the base mold cavity, forming a dovetail joint.

[0011] In some embodiments, the mold cavity includes a cylindrical cavity and a frustum cavity, the frustum cavity being connected to the cylindrical cavity, and the cross-sectional area of ​​the frustum cavity increasing in the direction away from the cylindrical cavity; along the through direction of the mold base, the length of the cylindrical cavity is d, the length of the frustum cavity is D, 1 / 10 ≤ d / D ≤ 1, or the angle between the generatrix of the frustum cavity and the rotation center line is a, 1 degree ≤ a ≤ 45 degrees.

[0012] In some embodiments, the nozzle for expanding heat shrink tubing includes at least one of the following features:

[0013] a) At least one of the base mold and the cover mold is made of a homogeneous material, an alloy material, or a composite material;

[0014] b) The surfaces of the mold base cavity and the mold cover cavity each include a coating, the material of which is polytetrafluoroethylene or ceramic.

[0015] In some embodiments, the base mold cavity and the cover mold cavity are centrally symmetrical, and one of the cover mold and the base mold rotates relative to the other to achieve the closing.

[0016] According to another aspect of the present invention, an expansion machine is further provided. The expansion machine includes any of the aforementioned nozzles for expanding heat shrink tubing, a vacuum expansion device, and a traction wheel. The vacuum expansion device is located between the traction wheel and the nozzle for expanding heat shrink tubing.

[0017] Compared with the prior art, the die and expansion machine for expanding heat shrink tubing provided by this utility model have at least the following beneficial effects:

[0018] The aforementioned die for expanding heat shrink tubing has a cover mold and a base mold that close together, forming a mold cavity. This can be understood as a die being divided into two parts along the direction of heat shrink tubing travel, with one part serving as the base mold and the other as the cover mold. Therefore, when the die needs to be replaced with another die, it is only necessary to disassemble the die, leaving the base mold and cover mold in an open state. Because the cross-section along the direction of heat shrink tubing travel is divided into two parts, there is no need to cut or remove the tubing, nor is it necessary to move the mold support or adjust the equipment parameters. When replacing other die with the heat shrink tubing expansion die of this application, the base mold and cover mold are closed to enclose the heat shrink tubing. At this time, the heat shrink tubing passes through the mold cavity. Therefore, since no tubing is cut or removed, it is not necessary to connect any cut tubing with tape when the equipment is turned on. In summary, the nozzle used for heat shrink tubing expansion is a simple, easy-to-disassemble, split nozzle. When replacing the nozzle, there is no need to cut or pull out the tubing; the nozzle can be removed directly without moving the mold support or adjusting equipment parameters. It also avoids the hassle of connecting the tubing when starting the equipment, effectively reducing manual operation time, thereby lowering labor costs and improving production efficiency.

[0019] Furthermore, in the production process of related technologies, the die nozzle requires the semi-finished tube to be passed through the nozzle first, and then through the vacuum expansion device and traction rollers. The nozzle outlet is typically smaller than the vacuum expansion device inlet. Therefore, this method carries the following risks: the semi-finished tube may not be able to pass through, and the tube piled up in the upper heating cylinder may fall, potentially causing burns, especially during dry expansion, where the tube moves from top to bottom, making the aforementioned problems more likely. However, the die nozzle for heat shrink tubing expansion in this application, because the cover mold and the base mold overlap, allows the semi-finished tube to pass through the vacuum expansion device and traction rollers first when changing the nozzle. Then, the cover mold and the base mold are closed to surround the tube. This process is completed after the semi-finished tube enters the vacuum expansion device and traction rollers. Therefore, the die nozzle for heat shrink tubing expansion helps avoid burns caused by the semi-finished tube not being able to pass through or the tube piled up in the upper heating cylinder falling. Attached Figure Description

[0020] The preferred embodiments will be described below in a clear and easy-to-understand manner, in conjunction with the accompanying drawings, to further explain the above-mentioned characteristics, technical features, advantages and implementation methods of this utility model.

[0021] Figure 1 This is a perspective view of the first type of die for expanding heat shrink tubing according to this application;

[0022] Figure 2 yes Figure 1 The side view shown is of the nozzle used for expanding heat shrink tubing.

[0023] Figure 3 It is along Figure 2 A cross-sectional view along line AA;

[0024] Figure 4 yes Figure 1 An exploded view of the nozzle used for expanding heat shrink tubing is shown.

[0025] Figure 5 yes Figure 4 A perspective view of the cover mold for the nozzle used for heat shrink tubing expansion;

[0026] Figure 6 This is a perspective view of the second type of die for expanding heat shrink tubing in this application;

[0027] Figure 7 yes Figure 6 A perspective view of the die holder for the nozzle used for heat shrink tubing expansion;

[0028] Figure 8 This is a cross-sectional view of one of the nozzles used for expanding heat shrink tubing in this application.

[0029] Explanation of icon numbers:

[0030] Mold base 1, mold base cavity 11, mold base cavity opening 111, mold base protrusion 12, mold base shaft hole 121, mold base through hole 13, mold base first cavity 112, mold base second cavity 113, cylindrical cavity 101;

[0031] Cover mold 2, cover mold cavity 21, cover mold cavity opening 211, cover mold protrusion 22, cover mold protrusion 22, cover mold pivot hole 221, cover mold through hole 23, tenon and mortise structure 24, protrusion 241, groove 242, limiting structure 25, limiting hole 251, limiting piece 252, frustum cavity 102, first cavity of cover mold 212, second cavity of cover mold 213;

[0032] Mold cavity 10. Detailed Implementation

[0033] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the specific implementation methods of this utility model will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of this utility model. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0034] To keep the drawings concise, each figure only schematically shows the parts relevant to the utility model, and these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of the components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."

[0035] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0036] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0037] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0038] Figure 1 , Figure 2 and Figure 4 The first type of nozzle for heat shrink tubing expansion is provided, which can be used for dry expansion. Figure 6 A second type of nozzle for heat shrink tubing expansion is provided. The two nozzles have different structural designs, which will be described in detail later. Both types of nozzles for heat shrink tubing expansion include a base mold 1 and a cover mold 2. The base mold 1 includes a base mold cavity 11, which penetrates the base mold 1, including its interior and a portion of its surface, to have a base mold cavity opening 111. That is, the base mold cavity opening 111 is formed because the base mold cavity 11 penetrates the base mold 1, and the length of the base mold cavity opening 111 is equal to the length of the base mold cavity 11 penetrating the base mold 1. The base mold cavity opening 111 connects the interior of the base mold cavity 11 and the exterior of the base mold 1.

[0039] The mold 2 includes a mold cavity 21 that penetrates the mold 2, including penetrating the interior and part of the surface of the mold 2, to have a mold cavity opening 211. Similarly, the mold cavity opening 211 is formed because the mold cavity 211 penetrates the interior and part of the surface of the mold 2. The mold cavity opening 211 connects the interior of the mold cavity 21 and the exterior of the mold 2; similarly, the length of the mold cavity opening 211 is equal to the length through which the mold cavity 21 penetrates.

[0040] The cover mold 2 and the base mold 1 are closed, thereby connecting the base mold cavity opening 111 and the cover mold cavity opening 211, so that the base mold cavity 11 and the cover mold cavity 21 form a mold cavity 10 through which the heat supply shrink tube passes along the through direction of the base mold 1. The way they are closed is not limited, as long as the mold cavity 10 can be formed.

[0041] In related technologies, the nozzle is divided into two parts along a cross-section perpendicular to the length of the heat shrink tubing. When changing the nozzle, the tubing needs to be cut or pulled out. When the equipment is turned on, the cut tubing needs to be connected with tape. The whole process is cumbersome, time-consuming, and labor-intensive, increasing manual labor time and affecting production efficiency.

[0042] As described above, the nozzle for heat shrink tubing expansion in this application can be understood as a nozzle divided into two parts by a cross-section along the heat shrink tubing's forward direction (or the axial direction of the heat shrink tubing). One part serves as the base mold 1, and the other part serves as the cover mold 2. Therefore, when it is necessary to replace the nozzle of this application with another nozzle (the other nozzle can be another nozzle with the same structure as this application, or a nozzle with a different structure), it is only necessary to disassemble the nozzle so that the base mold 1 and the cover mold 2 are in an open state. Because the cross-section along the heat shrink tubing's forward direction is divided into two parts, it is not necessary to cut or pull out the tubing during this process, nor is it necessary to move the mold support or adjust the equipment parameters. When it is necessary to replace other nozzles with the nozzle for heat shrink tubing expansion in this application, the base mold 1 and the cover mold 2 are closed to cover the heat shrink tubing. At this time, the heat shrink tubing passes through the mold cavity 10. Therefore, since no tubing is cut or pulled out, it is not necessary to connect the cut tubing with tape when the equipment is turned on.

[0043] In summary, the nozzle used for heat shrink tubing expansion is a simple, easy-to-disassemble, split nozzle. When replacing the nozzle, there is no need to cut or pull out the tubing; the nozzle can be removed directly without moving the mold support or adjusting equipment parameters. It also avoids the hassle of connecting the tubing when starting the equipment, effectively reducing manual operation time, thereby lowering labor costs and improving production efficiency.

[0044] Furthermore, in the production process of related technologies, the die nozzle requires the semi-finished tube to be passed through the nozzle first, and then through the vacuum expansion device and traction rollers. The nozzle outlet is typically smaller than the vacuum expansion device inlet. Therefore, this method carries the following risks: the semi-finished tube may not be able to pass through, or the tube stacked inside the upper heating cylinder may fall and cause burns, especially during dry expansion, where the tube moves from top to bottom, making the aforementioned problems more likely. However, the die nozzle for heat shrink tubing expansion in this application, because the cover mold 2 and the base mold 1 overlap, allows the semi-finished tube to pass through the vacuum expansion device and traction rollers first when changing the nozzle. Then, the cover mold 2 and the base mold 1 are closed to surround the tube. This process is completed after the semi-finished tube enters the vacuum expansion device and traction rollers. Therefore, the die nozzle for heat shrink tubing expansion helps avoid burns caused by the semi-finished tube not being able to pass through or the tube stacked inside the upper heating cylinder falling.

[0045] In some embodiments, the mold base cavity 11 and the mold cover cavity 21 are axially symmetrical. Axisymmetry can also be understood as the mold base cavity 11 and the mold cover cavity 21 being mirror images of each other and having the same size.

[0046] As described above, when the mold base cavity 11 and the mold cover cavity 21 are axially symmetrical, the mold base 1 and the mold cover 2 can be positioned radially (e.g., along the heat shrink tubing) Figure 4 The heat shrink tubing can be covered in the vertical direction (as shown), or along the axial direction (e.g., along the vertical direction). Figure 6 (As shown in the front and back) The cover is easy to close and convenient to surround the heat shrink tubing.

[0047] As a variation of the axisymmetric design of the mold base cavity 11 and the mold cover cavity 21, in other embodiments, the mold base cavity 11 and the mold cover cavity 21 are centrally symmetrical, and one of the mold cover 2 and the mold base 1 rotates relative to the other to achieve the closing. This embodiment also makes it convenient for the mold base 1 and the mold cover 2 to close and for the heat shrink tubing to be surrounded.

[0048] The following describes some implementation methods for fixing the cover mold 2 and the base mold 1.

[0049] See Figure 1 , Figure 2 , Figure 4 and Figure 5The cover mold 2 and the base mold 1 each include a first side and a second side opposite to each other. The first side of the cover mold 2 and the first side of the base mold 1 are rotatably connected. The rotatable connection can be achieved by a hinge. For example, the right side of the cover mold 2 includes two cover mold protrusions 22 spaced apart along its length, each cover mold protrusion 22 including a cover mold pivot hole 221. The right side of the base mold 1 includes a base mold protrusion 12, which also includes a base mold pivot hole 121. The base mold protrusion 12 is located between the two cover mold protrusions 22, and a pivot (not shown in the figure) passes through the base mold pivot hole 121 and the cover mold pivot hole 221, thereby achieving a pivot connection. The second side of the cover mold 2 and the second side of the base mold 1 are detachably connected; when the second side is detached, the cover mold 2 can be flipped relative to the base mold 1. Therefore, the detachable connection method is not limited, as long as the connection between the cover mold 2 and the base mold 1 on the second side can be released, allowing them to flip. Figure 1 In the disassembled state, the cover mold 2 is flipped along arrow R, and the cover mold 2 and the base mold 1 are opened. At this time, the mold nozzle can be removed. When the cover mold 2 and the base mold 1 are in the open state, the cover mold 2 is flipped along arrow r, and the cover mold 2 and the base mold 1 are closed. After the cover is closed, the cover mold 2 and the base mold 1 are not detachable.

[0050] As described above, by rotatably connecting the cover mold 2 and the base mold 1 on the first side and detachably connecting them on the second side, firstly, the cover mold 2 and the base mold 1 will not move relative to each other in the axial and radial directions, ensuring the stability of the nozzle during continuous production. Secondly, the rotatable connection on the first side and the detachable connection on the second side allow for nozzle replacement by flipping the cover mold 2 in different directions, making it convenient to replace the nozzle used for heat shrink tubing expansion.

[0051] The following describes some implementation methods for detachable connections:

[0052] See Figure 1 , Figure 4 and Figure 5 Both the second side of the cover mold 2 and the second side of the base mold 1 include through holes. The left side of the cover mold 2 includes a cover mold through hole 23, and the left side of the base mold 1 includes a base mold through hole 13. The die nozzle includes a bolt and a nut (not shown in the figure). The bolt passes through the cover mold through hole 23 of the cover mold 2 and the base mold through hole 13 of the base mold 1 and is locked by the nut. Thus, a detachable connection is achieved through the cooperation of the through holes, bolt, and nut.

[0053] In some other embodiments, one of the second side of the cover mold 2 and the second side of the base mold 1 is provided with a through hole, and the other is provided with a screw hole. The die nozzle includes a bolt, which passes through the through hole and connects to the screw hole. That is, compared with the aforementioned embodiments, this embodiment changes one of the through holes to a screw hole and omits the nut.

[0054] As a variation of the aforementioned threaded connection, the second side of the cover mold 2 and the second side of the base mold 1 are locked together by a snap-fit ​​structure. The structure of the snap-fit ​​is not limited.

[0055] As described above, the three structures that enable detachable connection between the second side of the base mold 1 and the second side of the cover mold 2, combined with the hinge connection, ensure reliable connection between the cover mold 2 and the base mold 1, guaranteeing the stability of the die nozzle during continuous production.

[0056] The following describes another embodiment of the connection between the base mold 1 and the cover mold 2:

[0057] See Figure 6 and Figure 7 The base mold 1 and the cover mold 2 are assembled by the mortise and tenon structure 24 and locked by the limiting structure 25, which is used to prevent relative movement between the tenon and the mortise of the mortise and tenon structure.

[0058] As described above, the combination of the tenon and mortise structure and the limiting structure ensures that, firstly, the cover mold 2 and the base mold 1 will not move relative to each other in the axial and radial directions, guaranteeing the stability of the die nozzle during continuous production. Secondly, by releasing the limiting structure 25 and withdrawing the tenon from the mortise, the cover mold 2 and the base mold 1 can be opened. Conversely, the two can be closed to enclose the tube, facilitating the replacement of the die nozzle, making it convenient to replace the die nozzle used for heat shrink tubing expansion.

[0059] Based on the function of the mortise and tenon structure 24 described above, and since the mortise and tenon structure 24 is not limited, one embodiment of the mortise and tenon structure 24 is described below:

[0060] See Figure 6 and Figure 7 One of the cover mold 2 and the base mold 1 is provided with a protrusion 241, and the other is provided with a groove 242. Here, the following situations are included: 1) such as Figure 6 and Figure 7 As shown, the base mold 1 is provided with a protrusion 241 and a groove 242, and the cover mold 2 is also provided with a protrusion 241 and a groove 242. The groove 242 of the base mold 1 corresponds to the protrusion 241 of the cover mold 2, and the groove 242 of the cover mold 2 corresponds to the protrusion 241 of the base mold 1; 2) The base mold 1 is provided with a protrusion 241, and the cover mold 2 is provided with a groove 242, which corresponds to the protrusion 241; 3) The base mold 1 is provided with a groove 242, and the cover mold 2 is provided with a protrusion 241, which corresponds to the groove 242. Both the groove 242 and the protrusion 241 extend along the through direction of the base mold cavity 11, forming a dovetail tenon.

[0061] As described above, the dovetail joint restricts the radial movement of the cover mold 2 and the base mold 1, and the limiting structure 25 restricts the movement of the cover mold 2 and the base mold 1 in the through direction, thereby ensuring the stability of the die nozzle during continuous production.

[0062] Based on the function of the limiting structure 25, the limiting structure 25 is not limited. For example, the limiting structure 25 includes a limiting hole 251 and a limiting member 252. The limiting member 252 and the limiting hole 251 extend in a direction perpendicular to the tenon and mortise structure, which is vertical in the figure. Limiting structures 25 are respectively provided on opposite sides of the die nozzle used for heat shrink tubing expansion. In the above embodiment, the limiting member 25 passes through the limiting hole 251 of the cover mold 2 and the limiting hole 251 of the base mold 1, thereby restricting the movement of the cover mold 2 and the base mold 1 in the exit direction perpendicular to the tenon and mortise structure.

[0063] See Figure 3 The mold cavity 10 includes a cylindrical cavity 101 and a frustum-shaped cavity 102, that is, see [link to mold cavity 10]. Figure 4 and Figure 5 The first cavity 112 of the mold base cavity 11 and the first cavity 212 of the mold cover cavity 21 form a cylindrical cavity 101. The second cavity 113 of the mold base cavity 11 and the second cavity 213 of the mold cover cavity 21 do not form a frustum-shaped cavity 102. In the above embodiment, both the first cavity 112 of the mold base cavity and the first cavity 212 of the mold cover cavity are semicircles, but they do not have to be semicircles as long as they form a cylindrical cavity 101. Both the second cavity 113 of the mold base cavity and the second cavity 213 of the mold cover cavity are semi-frustum-shaped, but they do not have to be semi-frustum-shaped as long as they can form a frustum-shaped cavity. The frustum-shaped cavity 102 is connected to the cylindrical cavity 101, and the cross-sectional area of ​​the frustum-shaped cavity 101 increases in the direction away from the cylindrical cavity 101. Along the through direction of the mold base 1, the length of the cylindrical cavity 101 is d, and the length of the frustum-shaped cavity 102 is D, where 1 / 10 ≤ d / D ≤ 1.

[0064] As described above, since 1 / 10≦d / D≦1, the cylindrical cavity 101 and the frustum cavity 102 are within a reasonable range, which is beneficial for low resistance of the tube and easy passage of the tube. More specifically, if d / D is greater than 1, the cylindrical cavity 101 is longer, the friction between the tube and the cavity wall of the cylindrical cavity 101 is greater, the resistance of the tube is greater, and the tube is not easy to pass through. Similarly, if d / D is less than 1 / 10, the frustum cavity 102 is longer, the friction between the tube and the cavity wall of the cylindrical cavity 101 is greater, the resistance of the tube is greater, and the tube is not easy to enter the inlet of the vacuum expansion device and is not easy to pass through.

[0065] In some preferred implementations, 1 / 5 ≦ d / D ≦ 1 / 2.

[0066] In some other embodiments, the angle between the generatrix of the frustum cavity 102 and the rotation center line is α, where 1 degree ≤ α ≤ 45 degrees, for example, 1 degree, 5 degrees, 8 degrees, 10 degrees, 12 degrees, 15 degrees, 18 degrees, 20 degrees, 22 degrees, 25 degrees, 28 degrees, 30 degrees, 32 degrees, 35 degrees, 38 degrees, 40 degrees, or 45 degrees.

[0067] As set up above, since 1 degree ≤ a ≤ 45 degrees, materials can be saved and the success rate of heat shrink tubing expansion is also higher. This is because if a is less than 1 degree, the angle is too small, the thread is too long, and too much material is needed to process the parts. If a is greater than 45 degrees, the expansion of the heat shrink tubing will fail.

[0068] In some preferred implementations, 3 degrees ≦a ≦30 degrees, for example, 3 degrees, 5 degrees, 7 degrees, 9 degrees, 10 degrees, 12 degrees, 13 degrees, 15 degrees, 16 degrees, 18 degrees, 20 degrees, 22 degrees, 23 degrees, 25 degrees, 28 degrees, or 30 degrees.

[0069] It should be noted that in the accompanying drawings of this application... Figures 1-7 Showing the nozzle used for dry expansion. Figure 8 The nozzle used for oil bath expansion is shown.

[0070] Under different expansion conditions, the specific dimensions and section length of the mold cavity 10 can be adjusted as needed. Generally, under dry expansion conditions, since the heat shrink tubing is heated to a relatively limited degree and the expansion resistance is relatively large, the mold cavity 10 generally adopts a relatively small diameter and a correspondingly longer axial length, so that the length d of the cylindrical cavity 101 and the length D of the frustum cavity 102 are both relatively long, in order to form a sufficient transition and shaping section. Under oil bath expansion conditions, the tubing is sufficiently softened before entering the mold cavity 10, so a relatively large mold cavity size can be used, so that the diameter of the cylindrical cavity 101 and the diameter of the frustum cavity 102 can be appropriately widened, and the lengths d and D can be appropriately shortened to meet the needs of rapid expansion and molding.

[0071] In some embodiments, the nozzle for expanding heat shrink tubing includes at least one of the following features:

[0072] a) At least one of the base mold 1 and cover mold 2 is made of a homogeneous material, an alloy material, or a composite material. The homogeneous material is a polar, high-temperature resistant homopolymer or copolymer polymer such as polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyamide (PA), polyimide (PI), polyamide-imide (PAI), polytetrafluoroethylene-perfluoroalkane propylene (PFA), perfluoroethylene propylene copolymer (FEP), or polyether ether ketone (PEEK). The alloy material is stainless steel, a polymer alloy, or a ceramic alloy. Furthermore, the stainless steel material used in the die for expanding the heat shrink tubing is austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, austenitic-ferritic duplex stainless steel, precipitation hardening stainless steel, or any combination of two or more of these alloys; furthermore, the polymer alloy used in the die is a polymer alloy formed from any two or more polar or high-temperature resistant polymer materials such as polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyamide (PA), polyimide (PI), polyamide-imide (PAI), polytetrafluoroethylene-perfluoroalkane propylene (PFA), perfluoroethylene propylene copolymer (FEP), and polyetheretherketone (PEEK); furthermore, the ceramic alloy is a silicon carbide ceramic alloy, a metal-based ceramic alloy, a cermet hard alloy, or any two or more of these materials. The composite material is a material whose fibers have been surface modified and reinforced. The fibers are inorganic silicate mineral fibers, polymer fibers, or metal fibers. The matrix is ​​a polymer material, metal, or ceramic. The fibers and the matrix can be arranged and combined to form a material with both excellent mechanical properties and good surface properties.

[0073] As described above, at least one of the base mold 1 and cover mold 2 is made of the aforementioned material, which is beneficial for the base mold 1 or cover mold 2 to be heat-resistant, lightweight, and not easily deformed. This material, combined with the base mold 1 and cover mold 2, forms the structure of the die nozzle. The cover mold 2 or base mold 1 is lightweight, heat-resistant, and not easily deformed, and the die nozzle is easy to disassemble and install.

[0074] In some other embodiments, the surfaces of the mold cavity 11 and the cover mold cavity 21 each include a coating, the coating being made of polytetrafluoroethylene or ceramic.

[0075] As described above, by applying a coating, the mold cavity 11 and the cover mold cavity 21 become smoother, with less resistance, making it easier for pipes to pass through and for pipes to expand.

[0076] Secondly, this application provides an expansion machine. The expansion machine includes any of the aforementioned die for expanding heat shrink tubing, a vacuum expansion device, and a traction wheel. The vacuum expansion device is located between the die for expanding heat shrink tubing and the traction wheel. That is, during the production of heat shrink tubing (without needing to change the die), the vacuum expansion device is located between the die for expanding heat shrink tubing and the traction wheel. Upon startup, the semi-finished tubing first passes through the rear-mounted vacuum expansion device and the traction wheel, and then the die surrounds the semi-finished tubing. When changing the die, there is no need to operate the vacuum expansion device and the traction wheel, nor is it necessary to remove the semi-finished tubing; the old die is directly removed and replaced with a die of a different specification, and then the machine is started normally.

[0077] With the above setup, the expander has the beneficial effects of the nozzle used for expanding heat shrink tubing.

Claims

1. A die for expanding heat shrink tubing, characterized in that, include: A mold base includes a mold base cavity that extends through the mold base, the mold base cavity forming a mold base cavity opening on the mold base, and the mold base cavity opening communicating with the interior of the mold base cavity and the exterior of the mold base; A cover mold, including a cover mold cavity extending through the cover mold, the cover mold cavity forming a cover mold cavity opening on the cover mold, the cover mold cavity opening communicating with the interior of the cover mold cavity and the exterior of the cover mold; The cover mold and the base mold are closed together, and the cavity opening of the base mold and the cavity opening of the cover mold are aligned, so that the cavity opening of the base mold and the cavity opening of the cover mold form a mold cavity through which the heat shrink tubing passes along the through direction of the base mold.

2. The die for expanding heat shrink tubing according to claim 1, characterized in that, The mold cavity and the cover mold cavity are axially symmetrical.

3. The die for expanding heat shrink tubing according to claim 2, characterized in that, The cover mold and the base mold each include a first side and a second side opposite to each other; The first side of the cover mold and the first side of the base mold are rotatably connected; the second side of the cover mold and the second side of the base mold are detachably connected; when the second side is detached, the cover mold can be flipped relative to the base mold.

4. The die for expanding heat shrink tubing according to claim 3, characterized in that, Both the second side of the cover mold and the second side of the base mold include through holes, and the mold nozzle includes a bolt and a nut, wherein the bolt passes through the through hole and is locked by the nut; Alternatively, one of the second side of the cover mold and the second side of the base mold may be provided with a through hole, and the other may be provided with a screw hole. The nozzle for expanding the heat shrink tubing includes a bolt, which passes through the through hole and is connected to the screw hole. Alternatively, the second side of the cover mold and the second side of the base mold are locked together by a snap-fit ​​structure.

5. The die for expanding heat shrink tubing according to claim 1, characterized in that, The base mold and the cover mold are assembled by a mortise and tenon structure; they are also locked by a limiting structure that prevents relative movement between the tenon and mortise of the mortise and tenon structure.

6. The nozzle for expanding heat shrink tubing according to claim 5, characterized in that, One of the cover mold and the base mold is provided with a protrusion, and the other is provided with a groove; both the groove and the protrusion extend along the through direction of the base mold cavity, forming a dovetail tenon.

7. The die for expanding heat shrink tubing according to claim 1, characterized in that, The mold cavity includes a cylindrical cavity and a frustum cavity, the frustum cavity is connected to the cylindrical cavity, and the cross-sectional area of ​​the frustum cavity increases in the direction away from the cylindrical cavity; Along the through direction of the mold base, the length of the cylindrical cavity is d, and the length of the frustum cavity is D, 1 / 10≦d / D≦1; And / or, the angle between the generatrix of the frustum cavity and the rotation center line is α, where 1 degree ≤ α ≤ 45 degrees.

8. The die for expanding heat shrink tubing according to claim 1, characterized in that, a) At least one of the base mold and the cover mold is made of a homogeneous material, an alloy material, or a composite material; b) The surfaces of the mold base cavity and the mold cover cavity each include a coating, the material of which is polytetrafluoroethylene or ceramic.

9. The die for expanding heat shrink tubing according to claim 1, characterized in that, The base mold cavity and the cover mold cavity are centrally symmetrical, and one of the cover mold and the base mold rotates relative to the other to achieve the closing.

10. An expansion machine, characterized in that, The expansion machine includes: The die, vacuum expansion device, and traction wheel for expanding heat shrink tubing as described in any one of claims 1 to 9; The vacuum expansion device is located between the traction wheel and the nozzle used for expanding the heat shrink tubing.

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