CN220482520U - Pipe color line forming die - Google Patents

Abstract

The utility model relates to a pipe color line forming die which comprises a die holder, a die holder outer sleeve, a color line feeding body, an inner die body, a shrinkage port, a shrinkage core, a die and a die core, wherein the die holder outer sleeve, the color line feeding body, the shrinkage port and the die are sequentially and detachably connected to enable the inner cavity side wall of the die holder outer sleeve to form the outer side wall of a flow channel, the die holder, the inner die body, the shrinkage core and the die core are sequentially and detachably connected to enable the die holder outer sleeve, the inner die body, the shrinkage core and the die core to form the inner side wall of the flow channel, and the section of the flow channel from the color line feeding body to the die is gradually reduced so that the pressure born by the raw materials in the flow channel is larger when the raw materials are closer to the outlet of the flow channel. The color line pan feeding body in this scheme sets up between die holder overcoat and shrink mouth, is located the middle section of mould when the pigment gets into the mould, has sufficient distance and the raw materials fusion in the runner after the pigment gets into the runner to follow the color line pan feeding body on the runner and its cross-section of bush reduces gradually, make the raw materials in the runner be close to the pressure that mould discharge gate it received more, receive the better fusion of tubular product raw materials and pigment behind bigger pressure.

Description

Pipe color line forming die

Technical Field

The utility model relates to the technical field of pipe molds, in particular to a pipe color line forming mold.

Background

The color line on the surface of the PE pipe is generally formed by co-extrusion, the color line feeding port is arranged at the part of the forming section of the die, the color line feeding port is added on the die, the color line layer is guided to be compounded on the pipe main body, however, as the distance between the die and the discharging port of the die is relatively short, the pigment is extruded from the flow channel after entering the flow channel and raw materials in the flow channel are not well fused, the color line on the extruded pipe is not fully fused with the pipe, an obvious boundary line exists between the color line and the pipe, and when a plurality of color lines exist on the pipe, the color lines are not fully fused with the pipe, and the color lines are unevenly distributed on the pipe, so that the quality of the pipe does not accord with the standard.

Disclosure of Invention

The utility model provides a pipe color line forming die for solving the problem of insufficient fusion between a color line and a pipe in the prior art. The mould in this scheme can make tubular product raw materials and colour line carry out good fusion, avoids having obvious boundary line's condition to appear between colour line and the tubular product after the extrusion.

The technical scheme adopted by the utility model is as follows: the utility model provides a tubular product colour line forming die, including the die holder, the die holder overcoat, colour line pan feeding body, the internal mold body, the shrink body, shrink core, bush and mold core, the die holder overcoat, colour line pan feeding body, shrink body and bush can dismantle in proper order and connect the lateral wall that makes its inner chamber lateral wall form the runner, the inside wall that makes it form the runner is dismantled in proper order to die holder, the internal mold body, shrink core and mold core, from colour line pan feeding body to its cross-section of bush gradually reduce in the runner for the raw materials is close to the pressure that the runner export received more in the runner.

The color line pan feeding body in this scheme sets up between die holder overcoat and the shrink body, be located the middle section of mould when the pigment gets into the mould, there is sufficient distance and the raw materials fusion in the runner after the pigment gets into the runner to follow the color line pan feeding body on the runner and its cross-section of bush reduces gradually, make the raw materials in the runner be close to the pressure that mould discharge gate it received more, the pressure that the raw materials received is bigger more, the fusion nature of tubular product raw materials and pigment is just better, consequently, the mould in this scheme can further make pigment and raw materials fully fuse, avoid there is obvious boundary between color line and the tubular product.

Preferably, the color line splitting device further comprises a color line splitting body, a positioning groove is formed in the color line feeding body, the color line splitting body is located in the positioning groove, the color line splitting body is detachably connected with the color line feeding body, the color line splitting body comprises a main groove and a plurality of splitting grooves, one ends of the splitting grooves are communicated with the main groove, the other ends of the splitting grooves are communicated with the flow channels, and the main groove is communicated with a color line feeding port in the color line feeding body. After the pigment enters the color line feeding body, the pigment flows into the main groove of the color line split-flow body from the color line feeding port on the color line feeding body, then flows into the split-flow groove from the main groove, finally flows out of the split-flow groove and flows into the flow channel. The color material entering the runner from the color line feeding body is split by the plurality of splitter boxes, so that a plurality of color lines can be distributed on the molded pipe.

Preferably, the shunt groove is provided with a shrinkage opening, the shrinkage opening is positioned at one end of the shunt groove, which is communicated with the flow channel, the shunt groove is communicated with the flow channel through the shrinkage opening, the width of the main groove is 1.3-1.4 times of that of the shunt groove, the width of the shunt groove is 1.9-2.1 times of that of the shrinkage opening, the depth of the shunt groove, which is close to one end of the main groove, gradually decreases to the depth, which is close to one end of the shrinkage opening, of the shunt groove, the depth h1, which is close to one end of the main groove, of the shunt groove is greater than the depth h2, which is close to one end of the shrinkage opening, of the shunt groove, and the depth h2, which is close to one end of the shrinkage opening, of the shunt groove is greater than the depth h3 of the shrinkage opening. The pressure that the pigment is stressed by the pigment after entering the color line shunt body is larger when the pigment is closer to the flow channel, so that the extrusion pressure is larger when the pigment enters the flow channel, and the fusion property of the pigment and the raw material of the inner pipe in the flow channel is better. Experiments show that when the width of the groove is 1.3-1.4 times of the width of the diversion groove, the width of the diversion groove is 1.9-2.1 times of the width of the shrinkage port, the depth of the diversion groove, which is close to one end of the main groove, is gradually decreased to the depth, which is close to one end of the shrinkage port, and the pigment can have enough extrusion pressure to ensure that the pigment has better fusion with the pipe raw material after entering the flow passage.

Preferably, one end of the shunt groove, which is communicated with the shrinkage port, is provided with a rounding angle. The round angle arranged at one end of the shunt tank communicated with the shrinkage port can play a role in diversion, so that the pigment in the shunt tank can smoothly flow into the shrinkage port, and the problem that the pigment is reversed due to the fact that the section of the shrinkage port is smaller than the section of the shunt tank when the pigment flows to one end of the shunt tank close to the shrinkage port is avoided.

Preferably, the axis of the main groove is semicircular, a color line feeding port on the color line feeding body is communicated with the middle of the main groove, two shunt grooves are connected at two ends of the color line feeding body, the two shunt grooves are symmetrically distributed by taking the connecting line of the circle centers of one end, communicated with the two shunt grooves, of the main groove and the color line split fluid as a symmetrical axis, and the included angle of the axes of the shrinkage ports on the two shunt grooves is 90 degrees. The color line feed inlet is communicated with the middle part of the main groove, four diversion grooves are grouped in pairs and are respectively positioned at two ends of the main groove, so that pigment can enter the diversion grooves at two ends of the main groove simultaneously after entering the main groove, and the contraction openings on the four diversion grooves are circumferentially equidistantly distributed by taking the circle center of the color line diversion body as a symmetry point, so that four uniformly distributed color lines can be formed on the pipe. And in the same way, three split-flow grooves, five split-flow grooves and six split-flow grooves can be arranged on the main groove according to actual needs, so that three color lines, five color lines and six color lines are arranged on the pipe. When a plurality of color lines are arranged on the pipe, only the contraction openings on the plurality of shunt grooves are required to be arranged at equal intervals by taking the center of the color line fluid as a symmetrical point.

Preferably, a first bulge is arranged at one end, close to the color line feeding body, of the die holder outer sleeve, a first groove is arranged at one end, close to the die holder outer sleeve, of the color line feeding body, and when the die holder outer sleeve is connected with the color line feeding body, the first bulge is positioned in the first groove; the die holder is provided with a first protrusion at one end close to the die holder, and a first groove is arranged at one end close to the die holder. The setting of first arch and first recess is more convenient for carry out accurate location between the die holder overcoat and the color line pan feeding body when connecting the two, and the setting of second arch and second recess is more convenient for carry out accurate location between the two when die holder and interior mould are connected.

Preferably, a third groove is formed in one end, close to the die, of the shrinkage body, a third protrusion is formed in one end, close to the inner die, of the die, and when the shrinkage body is connected with the die, the third protrusion is located in the third groove, and the end face of the third protrusion is attached to the end face of the shrinkage body. The arrangement of the third bulge and the third groove is convenient for accurate positioning between the shrinkage body and the neck mold when the shrinkage body is connected with the neck mold.

Preferably, the device further comprises a die pressing plate, when the third protrusion is located in the third groove, the end face of the third protrusion is flush with the end face of the shrinkage body, the die pressing plate is detachably connected with the shrinkage body, when the die pressing plate is connected with the shrinkage body, the die pressing plate is sleeved on the die, the side wall of the die is tightly attached to the side wall of the die pressing plate, and the end face, close to one end of the shrinkage body, of the die pressing plate is abutted to the end face of the shrinkage body and the end face of the third protrusion. The die is more convenient to install on the shrinkage body after the die pressing plate is arranged.

Preferably, the corner of the inner cavity of the runner is provided with a rounding. The inclined outer side wall of the shrinkage core is provided with a rounding, and the inclined inner side wall of the inner cavity of the shrinkage body is provided with a rounding. The corner of the inner cavity of the runner is provided with the rounding, so that raw materials in the runner can smoothly pass through the corner after flowing through the corner, the rounding plays a role in drainage, and the phenomenon of raw material backflow at the corner of the runner is avoided. The corners of the flow channel are arranged on the flow channel formed between the shrinkage body and the shrinkage core, so that the shrinkage body and the shrinkage core are provided with rounding corners.

Compared with the prior art, the utility model has the beneficial effects that: the color line pan feeding body in this scheme sets up between die holder overcoat and shrink mouth, and it is longer in the route of runner after the pigment entering runner, makes pigment and raw materials have more sufficient time to fuse, from its cross-section of color line pan feeding body to bush on the runner reduces gradually, makes the raw materials be close to the pressure that the mould discharge gate is its more that receives more, and the pressure that the raw materials received is more, and the pipe material is better with the fusibility of pigment, therefore, the mould in this scheme can further make pigment and raw materials fully fuse, avoids there is obvious boundary between color line and the pipe. Through the arrangement of the color line diversion body, after the pigment entering the runner from the color line feeding body is diverted through the diversion groove, a plurality of color lines can be obtained on the formed pipe.

Drawings

FIG. 1 is a partial cross-sectional view of a tube color line forming mold of the present utility model;

FIG. 2 is a schematic view of a color line split flow of a tube color line forming die according to the present utility model;

fig. 3 is a section a of fig. 2 of a tube color line forming die according to the present utility model.

Detailed Description

The drawings are for illustrative purposes only and are not to be construed as limiting the present patent; for better illustration of the present embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the actual product size; it will be appreciated by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted. The positional relationship depicted in the drawings is for illustrative purposes only and is not to be construed as limiting the present patent.

The same or similar reference numerals in the drawings of the embodiments of the present utility model correspond to the same or similar components; in the description of the present utility model, it should be understood that, if there are orientations or positional relationships indicated by terms "upper", "lower", "left", "right", "long", "short", etc., based on the orientations or positional relationships shown in the drawings, this is merely for convenience in describing the present utility model and simplifying the description, and is not an indication or suggestion that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so that the terms describing the positional relationships in the drawings are merely for exemplary illustration and are not to be construed as limitations of the present patent, and that it is possible for those of ordinary skill in the art to understand the specific meaning of the terms described above according to specific circumstances.

The technical scheme of the utility model is further specifically described by the following specific embodiments with reference to the accompanying drawings:

example 1

Referring to fig. 1-3, an embodiment 1 of a pipe color line forming mold is shown, which comprises a mold base 1, a mold base outer sleeve 2, a color line feeding body 3, an inner mold 4, a shrinkage body 5, a shrinkage core 6, a neck mold 7 and a mold core 8, wherein the mold base outer sleeve 2, the color line feeding body 3, the shrinkage body 5 and the neck mold 7 are sequentially and detachably connected to form the outer side wall of a runner 11 on the inner cavity side wall, the mold base 1, the inner mold 4, the shrinkage core 6 and the mold core 8 are sequentially and detachably connected to form the inner side wall of the runner 11, and the cross section of the runner 11 from the color line feeding body 3 to the neck mold 7 is gradually reduced to enable the pressure applied to raw materials in the runner 11 to be larger when the raw materials are closer to the outlet of the runner 11.

The beneficial effects of this embodiment are: the color line pan feeding body 3 in this scheme sets up between die holder overcoat 2 and shrinkage body 5, be located the middle section of mould when the pigment gets into the mould, there is sufficient distance and the raw materials fusion in the runner 11 after the pigment gets into runner 11, and its cross-section of runner 11 follow color line pan feeding body 3 to bush 7 reduces gradually, make the raw materials in the runner 11 be close to the pressure that mould discharge gate it received more, the pressure that the raw materials received is bigger more, the better the fusion nature of tubular product raw materials and pigment is just, consequently, the mould in this scheme can further make pigment and raw materials fully fuse, avoid having obvious boundary between color line and the tubular product.

Example 2

Example 2 of a pipe color line forming die, as shown in fig. 1-3, further comprises a color line splitting body 9 on the basis of example 1.

Specifically, the color line separating body 9 is further arranged on the color line feeding body 3, the color line separating body 9 is located in the locating groove, the color line separating body 9 is detachably connected with the color line feeding body 3, the color line separating body 9 comprises a main groove 901 and a splitter box 902, one end of the splitter box 902 is communicated with the main groove 901, the other end of the splitter box 902 is communicated with the runner 11, and the main groove 901 is further communicated with the color line feeding opening 301 in the color line feeding body 3.

Specifically, the split-flow groove 902 is provided with a shrinkage port 903, the shrinkage port 903 is positioned at one end of the split-flow groove 902, which is communicated with the flow channel 11, the split-flow groove 902 is communicated with the flow channel 11 through the shrinkage port 903, the width of the main groove 901 is 1.3-1.4 times that of the split-flow groove 902, the width of the split-flow groove 902 is 1.9-2.1 times that of the shrinkage port 903, the depth of the split-flow groove 902 from one end close to the main groove 901 to one end close to the shrinkage port 903 gradually decreases, the depth h1 of the split-flow groove 902 from one end close to the main groove 901 is greater than the depth h2 of the split-flow groove 902 from one end close to the shrinkage port 903, and the depth h2 of the split-flow groove 902 from one end close to the shrinkage port 903 is greater than the depth h3 of the shrinkage port 903. The shunt channel 902 has a rounded corner at the end that communicates with the pinch 903.

Specifically, the axis of the main groove 901 is semicircular, the color line feeding port 301 on the color line feeding body 3 is communicated with the middle of the main groove 901, four splitting grooves 902 are respectively a first splitting groove 902, a second splitting groove 902, a third splitting groove 902 and a fourth splitting groove 902, the first splitting groove 902 and the second splitting groove 902 are communicated with one end of the main groove 901, and the third splitting groove 902 and the fourth splitting groove 902 are communicated with the other end of the main groove 901. The first diversion trench 902 and the second diversion trench 902 are symmetrically arranged by taking the connecting line of the circle centers of one end, which is communicated with the first diversion trench 901 and the color line diversion body 9, of the main trench 901 as a symmetry axis, and the included angle of the axes of the shrinkage ports 903 of the two diversion trenches 902 is 90 degrees. The third diversion channel 902 and the fourth diversion channel 902 are symmetrically arranged by taking the connecting line of the circle centers of one end, which is communicated with the third diversion channel 902 and the fourth diversion channel 902, of the main channel 901 and the color line diversion body 9 as symmetry axes, and the included angle of the axes of the shrinkage ports 903 of the two diversion channels 902 is 90 degrees.

The beneficial effects of this embodiment are: the color line splitting body 9 splits the color materials entering the runner 11 from the color line feeding body 3 through the splitting groove 902, so that a plurality of color lines can be distributed on the molded pipe. As proved by experiments, when the width of the groove is 1.3-1.4 times of the width of the diversion groove 902, the width of the diversion groove 902 is 1.9-2.1 times of the width of the shrinkage 903, the depth of the diversion groove 902 near one end of the main groove 901 is gradually decreased to the depth near one end of the shrinkage 903, and the pigment can have enough extrusion pressure to ensure that the pigment has better fusion property with the pipe material after entering the flow channel 11. The rounded corner arranged at one end of the shunt tank 902 communicated with the shrinkage port 903 can play a role in diversion, so that the pigment in the shunt tank 902 can smoothly flow into the shrinkage port 903, and the phenomenon that the pigment is reversed when flowing to one end of the shunt tank 902 close to the shrinkage port 903 because the section of the shrinkage port 903 is smaller than the section of the shunt tank 902 is avoided. The color line feeding port 301 is communicated with the middle of the main groove 901, and the four diversion grooves 902 are grouped in pairs and are respectively positioned at two ends of the main groove 901, so that the pigment can enter the diversion grooves 902 at two ends of the main groove 901 simultaneously after entering the main groove 901, and the shrinkage ports 903 on the four diversion grooves 902 are circumferentially and equidistantly distributed by taking the circle center of the color line splitting body 9 as a symmetrical point, so that four color lines which are uniformly distributed can be formed on the pipe.

Example 3

Example 3 of a tube color line forming mold, as shown in fig. 1-3, the structure of the mold is further defined on the basis of example 1 or example 2.

Specifically, a first bulge is arranged at one end, close to the color line feeding body 3, of the die holder outer sleeve 2, a first groove is arranged at one end, close to the die holder outer sleeve 2, of the color line feeding body 3, and when the die holder outer sleeve 2 is connected with the color line feeding body 3, the first bulge is positioned in the first groove; the die holder 1 is provided with a second bulge at one end close to the inner die body 4, and a second groove is arranged at one end close to the die holder 1 on the inner die body 4, and when the die holder 1 is connected with the inner die body 4, the second bulge is positioned in the second groove.

Specifically, a third groove is formed in one end, close to the die 7, of the shrinkage body 5, a third protrusion is formed in one end, close to the inner die 4, of the die 7, and when the shrinkage body 5 is connected with the die 7, the third protrusion is located in the third groove, and the end face of the third protrusion is attached to the end face of the shrinkage body 5. The plastic compression molding device further comprises a die pressing plate 10, when the third protrusion is located in the third groove, the end face of the third protrusion is flush with the end face of the shrinkage body 5, the die pressing plate 10 is detachably connected with the shrinkage body 5, when the die pressing plate 10 is connected with the shrinkage body 5, the die pressing plate 10 is sleeved on the die 7, the side wall of the die 7 is tightly attached to the side wall of the die pressing plate 10, and the end face, close to one end of the shrinkage body 5, on the die pressing plate 10 is abutted to the end face of the shrinkage body 5 and the end face of the third protrusion.

Specifically, the corner of the inner cavity of the runner 11 is provided with a rounding. The inclined outer side wall of the shrinkage core 6 is provided with a rounding, and the inclined inner side wall of the inner cavity of the shrinkage body 5 is provided with a rounding.

The beneficial effects of this embodiment are: the arrangement of the first bulge and the first groove is more convenient for accurate positioning between the die holder outer sleeve 2 and the color wire feeding body 3 when the die holder outer sleeve 2 and the color wire feeding body 3 are connected, and the arrangement of the second bulge and the second groove is more convenient for accurate positioning between the die holder 1 and the inner die body 4 when the die holder 1 and the inner die body 4 are connected. The arrangement of the third protrusion and the third groove facilitates accurate positioning between the shrinkage body 5 and the die 7 when the two are connected. The die plate 10 is arranged to facilitate the installation of the die 7 on the shrinkage body 5. The corner of the inner cavity of the runner 11 is provided with the rounding, so that raw materials in the runner 11 can smoothly pass through the corner after flowing through the corner, the rounding plays a role in drainage, and the phenomenon of raw material backflow at the corner of the runner 11 is avoided.

It is to be understood that the above examples of the present utility model are provided by way of illustration only and not by way of limitation of the embodiments of the present utility model. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the utility model are desired to be protected by the following claims.

Claims (10)

1. The utility model provides a tubular product colour line forming die, its characterized in that, including die holder (1), die holder overcoat (2), colour line pan feeding body (3), interior die body (4), shrink body (5), shrink core (6), bush (7) and mold core (8), die holder overcoat (2 colour line pan feeding body (3) shrink body (5) with the die core (7) can be dismantled in proper order and connect the lateral wall that makes its inner chamber lateral wall form runner (11), die holder (1) interior die body (4) shrink core (6) with the mold core (8) can be dismantled in proper order and connect the inside wall that makes it form runner (11), from colour line pan feeding body (3) to its cross-section of bush (7) gradually reduce in runner (11) is used for making the raw materials be close to the pressure that runner (11) export received more in the runner (11).

2. The pipe color line forming die according to claim 1, further comprising a color line split body (9), wherein a positioning groove is formed in the color line feeding body (3), the color line split body (9) is located in the positioning groove, the color line split body (9) is detachably connected with the color line feeding body (3), the color line split body (9) comprises a main groove (901) and a split groove (902), the split groove (902) is provided with a plurality of split grooves (902), one end of each split groove (902) is communicated with the main groove (901), the other end of each split groove is communicated with the runner (11), and the main groove (901) is further communicated with a color line feeding opening (301) in the color line feeding body (3).

3. The pipe color line forming die according to claim 2, wherein a shrinkage opening (903) is formed in the shunt groove (902), the shrinkage opening (903) is located at one end of the shunt groove (902) which is communicated with the flow channel (11), the shunt groove (902) is communicated with the flow channel (11) through the shrinkage opening (903), the width of the main groove (901) is 1.3-1.4 times of the width of the shunt groove (902), the width of the shunt groove (902) is 1.9-2.1 times of the width of the shrinkage opening (903), the depth of the shunt groove (902) which is close to one end of the main groove (901) is gradually reduced to one end which is close to the shrinkage opening (903), and the depth h1 of the shunt groove (902) which is close to one end of the main groove (903) is larger than the depth h2 of the shunt groove (902) which is close to one end of the shrinkage opening (903), and the depth h2 of the shunt groove (902) which is close to one end of the shrinkage opening (903) is larger than the depth h 2.

4. A pipe color line forming mold according to claim 3, wherein a rounded corner is provided at an end of the shunt groove (902) communicating with the constriction (903).

5. A pipe color line forming die according to claim 3, wherein the axis of the main groove (901) is semicircular, a color line feeding port (301) on the color line feeding body (3) is communicated with the middle of the main groove (901), two split-flow grooves (902) are connected to two ends of the color line feeding body (3), the two split-flow grooves (902) are symmetrically arranged by taking the connecting line of the center of a circle of one end, which is communicated with the main groove (901), of the main groove (901) and the color line split-flow body (9) as a symmetrical axis, and the axis included angle of two shrinkage ports (903) on the two split-flow grooves (902) is 90 °.

6. The pipe color line forming die according to claim 1, wherein a first bulge is arranged at one end, close to the color line feeding body (3), of the die holder outer sleeve (2), a first groove is arranged at one end, close to the die holder outer sleeve (2), of the color line feeding body (3), and the first bulge is positioned in the first groove when the die holder outer sleeve (2) is connected with the color line feeding body (3); the die holder (1) is provided with a second bulge at one end close to the inner die (4), a second groove is formed at one end of the inner die (4) close to the die holder (1), and the second bulge is located in the second groove when the die holder (1) is connected with the inner die (4).

7. The pipe color line forming die according to claim 1, wherein a third groove is formed in one end, close to the die (7), of the shrinkage body (5), a third protrusion is formed in one end, close to the inner die (4), of the die (7), and the third protrusion is located in the third groove when the shrinkage body (5) is connected with the die (7).

8. The pipe color line forming die according to claim 7, further comprising a die pressing plate (10), wherein when the third protrusion is located in the third groove, an end face of the third protrusion is flush with an end face of the shrinkage body (5), the die pressing plate (10) is detachably connected with the shrinkage body (5), when the die pressing plate (10) is connected with the shrinkage body (5), the die pressing plate (10) is sleeved on the die (7), the side wall of the die (7) is tightly attached to the side wall of the die pressing plate (10), and an end face, close to one end of the shrinkage body (5), on the die pressing plate (10) is abutted with the end face of the shrinkage body (5) and the end face of the third protrusion.

9. The pipe color line forming die according to claim 1, wherein a corner of the inner cavity of the runner (11) is provided with a rounded corner.

10. The pipe color line forming die according to claim 1, wherein a rounding is arranged on the inclined outer side wall of the shrinkage core (6), and a rounding is arranged on the inclined inner side wall of the inner cavity of the shrinkage body (5).