Die capable of quickly changing specifications

Abstract

The utility model relates to the technical field of pipe molds, in particular to a mold capable of quickly changing specifications, which comprises a core rod and a core mold which are split, and further comprises a screw provided with external threads along the circumferential direction, a through shaft hole is formed in the core mold, a countersunk shaft hole is formed in the core rod, internal threads are arranged in the through shaft hole, and the countersunk shaft hole is provided with external threads. The core rod is detachably and fixedly connected with the core mold, and the screw penetrates through the countersunk shaft hole of the core rod and is connected with the internal thread of the core mold. When the mold is replaced, only the core rod needs to be replaced, the rejection rate caused by changing gaps of the whole mold is reduced, the core rods of different specifications can be replaced, and the applicability is higher; and in addition, screwing and fixing are carried out by means of a screw penetrating into the pipe, so that the pipe is firmer when being fed, extruded and processed and is not influenced by the problems such as difficulty in replacement of a plug-in port caused by glue feeding of a connecting port.

Description

Technical Field

[0001] The utility model relates to the technical field of pipe molds, in particular to a mold that can quickly change specifications. Background Technique

[0002] PE water supply pipes are mainly used in municipal water supply pipe systems. Different pipe specifications are required in different application areas, and a production line can produce various PE water supply pipes with different specifications. Currently, during the production process of a PE production line, when the specification needs to be changed, the machine needs to be stopped, the mold needs to be replaced, and after the temperature is raised to the required temperature of the production process, the machine is restarted to adjust the size of the required specification of the pipe. After a period of adjustment, when the pipe is qualified, normal production can be carried out. This process consumes a certain amount of time and produces a certain number of defective products.

[0003] Please refer to Figure 1 , most of the existing mandrel molds are of an integral structure, and the whole mold needs to be replaced when the mold is changed, which is time-consuming and material-consuming; the Chinese utility model patent CN214820744U provides a combined mandrel that can be quickly replaced in a pipe mold, including a mandrel main body and a mandrel head; an internal thread groove is provided at the end of the mandrel main body, and an external thread connector for cooperating with the internal thread groove is provided at the end of the mandrel head. An annular groove is provided on the outer side of the end of the mandrel main body, and a sealing sleeve adapted to the annular groove is fixedly connected to the end of the mandrel head. The sealing sleeve is sleeved on the annular groove, and the sealing sleeve and the annular groove are in interference fit. A chamfer is provided on one side of the annular groove close to the mandrel head to facilitate the introduction of the sealing sleeve into the annular groove, and a gap is provided between the side of the annular groove far from the mandrel head and the sealing sleeve. The above solution adopts a split design of the core mold and the mandrel, and the connection port A is fixed by multi-layer threaded screwing and sealing. However, due to the large extrusion stress concentration on the connection port during pipe extrusion, the above multi-layer threaded connection port design is not firm in actual use, and there are problems such as difficult screwing out due to glue entering the connection port when replacing the mandrel. Content of the Utility Model

[0004] To solve the problems in the above background technique, the present application provides a mold that can quickly change specifications, which can retain the common core mold in the die when changing the mold, only need to disassemble and replace the mandrel, saving materials and time, while ensuring the firm installation between the mandrel and the core mold, the connection port is not easy to get glue, and the replacement is fast.

[0005] To achieve the above object, the technical solutions provided by the present application are as follows:

[0006] A mold that can quickly change specifications, including a split mandrel and a core mold. The core mold is axially provided with a hollow through-axis hole, and the mandrel is axially provided with a counterbored hole. The through-axis hole is provided with internal threads, and further includes a screw with external threads arranged circumferentially. The mandrel and the core mold are detachably and fixedly connected. After the screw passes through the counterbored hole of the mandrel and enters the core mold, it is threadedly fixedly connected with the internal threads in the through-axis hole.

[0007] Further, the mandrel and the core mold are detachably plugged and fixed.

[0008] Further, a receiving circular groove is formed by inward concavity along the circumference at the front end of the core mold, and a cylindrical plug joint is formed by reducing the diameter at the rear end of the mandrel. The receiving circular groove and the plug joint are plugged and fixed, and the radius of the receiving circular groove is greater than that of the through-axis hole.

[0009] Compared with the prior art, the technical solution of the present application is that the ends of the split mandrel and the core mold are plugged and fixed, and then a screw is axially inserted to fasten the mandrel and the core mold. Thus, when replacing, the core mold does not move, only the mandrel needs to be replaced, and the two are firmly connected during processing without being affected by the glue entering the connection port. Only by removing the screw fastened in the counterbored hole can the work of replacing the mandrel be completed.

[0010] Preferably, a fastening portion is arranged circumferentially on the inner wall of the receiving circular groove, and a tightening portion is arranged circumferentially on the outer wall of the plug joint. The fastening portion and the tightening portion cooperate to fix. Based on the above solution, the preliminary fixation of the entire mandrel after the mandrel and the core mold are plugged can be further strengthened through the cooperation between the fastening portion and the tightening portion.

[0011] Specifically, both the fastening portion and the tightening portion are threads that can be screwed together and fixed. By arranging threads that can be screwed together and fixed on the inner wall of the receiving circular groove and the outer wall of the plug joint, the fastening after the mandrel and the core mold are plugged can be completed more conveniently.

[0012] Further, the fastening portion is a through groove arranged axially, and the tightening portion is a track protruding axially. The track is slidably inserted into the through groove for fixation. The slidable fixation setting of the through groove and the track can increase the fastening when the mandrel and the core mold are plugged, and is more convenient for disassembly than the fastening method of threads.

[0013] Further, the fastening portion is a circumferential annular groove, and the tightening portion is a circumferential elastic ring. The elastic ring is snap-fitted into the annular groove for fixation. The setting of the annular groove and the elastic ring can make the sealing better and the fastening more firm when the mandrel and the core mold are plugged.

[0014] Furthermore, the counterbored shaft hole includes a countersunk head section and a counterbored shaft section that are connected. An internal thread is provided at one end of the counterbored shaft section, which is screwed and fixedly connected to the external thread of the screw passing through the mandrel. An internal thread is also provided in the counterbored shaft section of the counterbored shaft hole, so that the screw can be pre-passed into the mandrel and fixed by threading. The screw head of the screw is limited and accommodated in the countersunk head section. When replacing the mandrel, the pre-fixed mandrel and screw are directly assembled into a kit and inserted into the core mold, and then the screw is tightened, making the replacement more time-saving and convenient.

[0015] Furthermore, the through shaft hole has an axially connected end through hole and a middle through hole. The part that is screwed and fixed to the screw is the end through hole. The radius of the end through hole is larger than that of the adjacent middle through hole and smaller than the receiving circular groove. By setting the middle through hole and the end through hole with different radii to jointly form the through shaft hole, on the one hand, the middle through hole with a small radius can form a restriction on the screw screwed into the end through hole, preventing the screw from being screwed too deep into the through shaft hole of the core mold. On the other hand, a better heat dissipation and exhaust channel can be formed.

[0016] Furthermore, the structure of the mandrel is integrally formed, and the structure of the core mold is also integrally formed.

[0017] The beneficial effects of the present utility model are as follows: By making the mandrel mold into a split mandrel and core mold, when replacing, the core mold is placed and fixed in the die head without moving, and only the mandrel needs to be replaced, reducing the rejection rate caused by changing the gap of the entire mandrel mold. As long as the plug joint specifications of the mandrel remain unchanged, it can be replaced with different model specifications, with stronger applicability; Since the fastening of the mandrel and the core mold not only depends on the insertion between the two, but more on the screw screwed into them for fixing, the overall mandrel mold composed of the assembled mandrel and core mold is more firm during the extrusion processing of pipe materials, and is not affected by problems such as difficult replacement of the insertion joint caused by glue injection at the connection port. Description of the Drawings

[0018] Figure 1 is the overall structural cross-sectional view of the prior art mandrel mold;

[0019] Figure 2 is the assembled cross-sectional view of the mandrel mold in Embodiment 1 of the present utility model;

[0020] Figure 3 is the structural cross-sectional view of the mandrel in Embodiment 1 of the present utility model;

[0021] Figure 4 is the structural cross-sectional view of the core mold in Embodiment 1 of the present utility model;

[0022] Figure 5 is Figure 2 the enlarged view of the partial A in

[0023] Figure 6It is a structural sectional view of the assembly of other models of mandrels and die molds in Embodiment 1 of the present utility model.

[0024] Among them, the markings in the figure are: 1 - existing mandrel, 2 - mandrel, 3 - die mold, 4 - screw, 5 - through shaft hole, 501 - end through hole, 502 - through hole, 6 - counterbored shaft hole, 601 - countersunk head section, 602 - counterbored shaft section, 7 - internal thread, 8 - receiving circular groove, 9 - plug joint. Specific implementation mode

[0025] The technical solutions in the present utility model will be clearly and completely described below in conjunction with the accompanying drawings in the present utility model. The components of the present utility model described and shown in the drawings here usually can be arranged and designed in various different configurations. Therefore, the following detailed description of the present utility model provided in the drawings is not intended to limit the scope of the present utility model claimed, but merely represents the selected embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present utility model.

[0026] Embodiment 1

[0027] To solve the problem that the existing mandrel in the background technology is integrally made (refer to Figure 1 ), when replacing, it is necessary to stop the machine and replace the mold as a whole, resulting in a large gap between the die orifice of the mold and the mandrel, causing a large amount of waste and time-consuming and laborious replacement; while the split mandrel has the problem that the connection at the connection port is not firm, and it is easy to get glue in, resulting in laborious replacement. The present utility model proposes a split mandrel mold that can quickly replace the specifications. The mandrel mold of the present utility model includes:

[0028] Please refer to Figure 2 The sectional view of the overall structure of the mandrel mold in, including the split mandrel 2 and the die mold 3. Both the mandrel 2 and the die mold 3 are integrally formed structures. Among them, the die mold 3 is arranged and fixed in the die orifice without replacement. Please refer to Figure 6 The sectional view of the overall structure of another model of mandrel and die mold. The mandrel 2 has multiple models and is the main replacement part.

[0029] Please refer to Figures 3 - 5, a hollow counterbore hole 6 is axially formed in the mandrel 2. The counterbore hole 6 includes a countersunk head section 601 and a counterbore section 602 that are connected. An internal thread 7 is provided inside one end of the counterbore section 602 close to the core mold 3 for screwing and fixing with the external thread of the screw 4 passing through the mandrel 2. After the screw 4 is screwed and fixed, the screw head is accommodated in the countersunk head section for positioning. The rear end of the mandrel 2 for plugging and fixing with the core mold 3 is formed into a cylindrical plug joint 9 by necking down. When replacing the mandrel 2, the pre-threaded fixed mandrel 2 and screw 4 assembly are directly plugged into the core mold 3, and then the screw 4 is tightened, making the replacement more time-saving and convenient.

[0030] , a hollow through-hole 5 is axially formed in the core mold 3. The front end of the core mold 3 is recessed inward along the circumference to form a receiving circular groove 8. The receiving circular groove 8 is plugged and fixed with the plug joint 9. The radius of the receiving circular groove 8 is greater than that of the through-hole 5. An internal thread 7 is provided in the through-hole 5 for screwing and fixing with the screw 4. In this embodiment, the through-hole 5 has an axially connected end through-hole 501 and a middle through-hole 502. The part for screwing and fixing with the screw 4 is the end through-hole 501. The radius of the end through-hole 501 is greater than that of the adjacent middle through-hole 502 and less than that of the receiving circular groove 8. The internal thread 7 is provided on the end through-hole 501 for screwing and fixing with the inserted screw 4. By setting the middle through-hole 502 and the end through-hole 501 with different radii to jointly form the through-hole 5, on the one hand, the small-radius middle through-hole 502 can limit the screwing of the screw 4 into the end through-hole 501, preventing the screw 4 from being screwed too deep into the through-hole 5 of the core mold 3. On the other hand, it can form a better heat dissipation and exhaust channel. The inner wall of the receiving circular groove 8 in this embodiment is provided with threads along the circumference as a fastening part. Similarly, the outer wall of the plug joint 9 is provided with matching threads along the circumference as a tightening part, and the two can be screwed and fixed to further strengthen the firmness when the mandrel 2 and the core mold 3 are plugged, contributing to the overall stability of the mandrel during the pipe feeding and extrusion.

[0031] Embodiment 2

[0032] Compared with Embodiment 1, in this embodiment, a plurality of through grooves are recessed inward along the axial direction on the inner wall of the receiving circular groove 8, and protrusions with the same size and number as the through grooves are provided on the outer wall of the plug joint 9 along the axial direction. The protrusions are integrally formed with the mandrel 2. The setting of the through grooves and the protrusions can increase the fastening when the mandrel 2 and the core mold 3 are plugged, and it is more convenient to disassemble than the thread fastening method. Other structures are the same as those in Embodiment 1.

[0033] Embodiment 3

[0034] Compared with Embodiment 1, in this embodiment, a ring groove is circumferentially formed on the inner wall of the receiving circular groove 8, and an elastic ring is sleeved on the outer wall of the corresponding plug connector 9. The elastic ring is snapped into the ring groove for fixation. The arrangement of the ring groove and the elastic ring can make the sealing between the mandrel 2 and the core mold 3 better and tighter during insertion. Other structures are the same as those in Embodiment 1.

[0035] By making the mandrel mold into a split mandrel 2 and core mold 3, when replacing, the core mold 3 is placed and fixed in the die head without moving, and only the mandrel 2 needs to be replaced, reducing the waste rate caused by changing the gap of the entire mandrel mold. As long as the specification of the plug connector 9 of the mandrel 2 remains unchanged, mandrels 2 of different shapes and models can be replaced, with stronger applicability; since the fastening of the mandrel 2 and the core mold 3 not only depends on the insertion between the two, but more on the screws 4 inserted into them for screwing and fixing, the overall mandrel mold composed of the assembled mandrel 2 and core mold 3 is more firm during the extrusion processing of pipe materials and is not affected by problems such as difficult replacement of the insertion interface caused by glue injection at the connection port.

[0036] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights. In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A mold capable of quickly changing specifications, comprising a separate mandrel (2) and a core mold (3), characterized in that: It also includes a screw (4) with an external thread along the circumferential direction, the core mold (3) has a hollow through-axis hole (5) along the axial direction, the core rod (2) has a countersunk axis hole (6) along the axial direction, the through-axis hole (5) has an internal thread (7), the core rod (2) and the core mold (3) are detachably fixedly connected, and the screw (4) passes through the countersunk axis hole (6) of the core rod (2) and is connected to the internal thread (7) of the core mold (3).

2. The mold capable of quickly changing specifications according to claim 1 is characterized in that: The core rod (2) and the core mold (3) are detachably plugged and fixed.

3. The mold capable of quickly changing specifications according to claim 2 is characterized in that: The front end of the core mold (3) is concave inward along the circumferential direction to form a receiving circular groove (8), and the rear end of the core rod (2) is reduced in diameter to form a cylindrical plug connector (9), and the receiving circular groove (8) and the plug connector (9) are plugged and fixed.

4. The mold capable of quickly changing specifications according to claim 3 is characterized in that: The inner wall of the receiving circular groove (8) is provided with a fastening portion in the circumferential direction, and the outer wall of the plug connector is provided with a tightening portion in the circumferential direction, and the fastening portion cooperates with the tightening portion for fixation.

5. The mold capable of quickly changing specifications according to claim 4 is characterized in that: The fastening portion and the tightening portion are threads that can be screwed together and fixed.

6. The mold capable of quickly changing specifications according to claim 4, characterized in that: The fastening portion is a through slot arranged along the axial direction, and the tightening portion is an axially protruding track, and the track is slidably inserted into the through slot and fixed.

7. The mold capable of quickly changing specifications according to claim 4 is characterized in that The fastening portion is a ring groove along the circumferential direction, and the tightening portion is an elastic ring along the circumferential direction. The elastic ring is engaged in the ring groove for fixing.

8. The mold capable of quickly changing specifications according to claim 1, characterized in that: The through-axis hole (5) comprises an end through hole (501) and a middle through hole (502) which are axially connected, wherein the portion which is screwed and fixed with the screw (4) is the end through hole (501), and the radius of the end through hole (501) is larger than that of the adjacent middle through hole (502).

9. The mold capable of quickly changing specifications according to claim 1, characterized in that: The countersunk shaft hole (6) comprises a connected countersunk head section (601) and a countersunk shaft section (602), wherein an internal thread (7) is provided at one end of the countersunk shaft section (602) for screwing and fixing with the external thread of the screw (4) passing through the core rod (2).

10. The mold capable of quickly changing specifications according to claim 1, characterized in that: The core rod (2) is an integrally formed part, and the core mold (3) is also an integrally formed part.

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