CN111660491A

CN111660491A - Three-dimensional injection molding device

Info

Publication number: CN111660491A
Application number: CN202010400020.3A
Authority: CN
Inventors: 易忠萍
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-13
Filing date: 2020-05-13
Publication date: 2020-09-15

Abstract

The invention relates to the technical field of machine manufacturing, and discloses a three-dimensional injection molding device which comprises a fixing plate, wherein the right side of the upper surface of the fixing plate is fixedly connected with a melting injection device through a vertical seat, the bottom of the melting injection device is provided with an upper module, and the interior of the upper module is fixedly connected with a side module through a linkage rod. This three-dimensional injection moulding device, through the replacement container, separator, the siphunculus, cooperation between type die cavity and the attemperator, utilize inside the filling of type die cavity to mould plastics equivalent high concentration pure liquid and occupy the inside volume of type die cavity, and then discharge the inside air of type die cavity, utilize attemperator to keep pure liquid and melting injection moulding liquid to be in the same temperature simultaneously, avoided present cost increase and time growth that causes through the air pump vacuumed condition, be favorable to improving this three-dimensional injection moulding device exhaust effect and reduce the exhaust cost, be favorable to guaranteeing the life of mould simultaneously.

Description

Three-dimensional injection molding device

Technical Field

The invention relates to the technical field of machine manufacturing, in particular to a three-dimensional injection molding device.

Background

An injection molding machine, also known as an injection molding machine or an injection machine, is called a beer machine in many factories, and an injection molded product is called a beer piece, and is a main molding apparatus for molding a thermoplastic plastic or a thermosetting material into plastic products of various shapes by using a plastic molding die, wherein an injection device and a mold clamping device are opened and closed in the same vertical center line, and the die occupies about half of the floor space of a horizontal machine, so that the productivity converted into the floor space is about twice.

When the existing injection molding device injects a plastic solution into a cavity of a grinding tool, air in the cavity needs to be discharged, the existing injection molding device generally pumps the air in the cavity by an air pump, namely the air in the cavity is pumped by the air pump to keep the interior of the cavity in a vacuum state, but the pumping process not only needs a long time and has higher manufacturing cost, but also hardly reaches the vacuum state by the air pump, vacuum bubbles still exist when the vacuum state is reached in time, if the bubbles in the cavity are not discharged in time, the product formed by plastic curing is not filled fully, and a welding seam is generated, even if the injection pressure is increased, after the pressure reaches a proper degree, the compressed air, the injection molding material and the cavity are mutually rubbed to generate a large amount of heat, so that local overheating in the cavity is caused, the plastic material is scorched, and is carbonized or even high molecules are decomposed, the product is unqualified, and the service life of the mold is shortened, so a three-dimensional injection molding device is provided.

Disclosure of Invention

The invention provides a three-dimensional injection molding device, which has the advantages of being beneficial to improving the exhaust effect of the three-dimensional injection molding device, reducing the exhaust cost and ensuring the service life of a mold, and solves the problems that when a plastic solution is injected into a cavity of a grinding tool, the existing injection molding device needs to exhaust air in the cavity, the existing injection molding device generally extracts air in the cavity by an air pump, namely the air in the cavity is extracted by the air pump to keep the interior of the cavity in a vacuum state, but the extraction process not only needs longer time and has higher manufacturing cost, but also is difficult to reach the vacuum state by the air pump, the vacuum bubble still exists when the vacuum state is reached in time, if the air bubble in the cavity is not discharged in time, the product formed by plastic curing is not filled fully, the welding seam is generated, even if the injection pressure is increased, when the pressure reaches a proper degree, the compressed gas, the injection molding material and the die cavity rub against each other to generate a large amount of heat, thereby causing local overheating in the die cavity, burning of the plastic material, carbonization and even decomposition of high molecules, causing unqualified products and simultaneously shortening the service life of the die.

In order to achieve the above purpose, the invention provides the following technical scheme to realize: a three-dimensional injection molding device comprises a fixed plate, wherein the right side of the upper surface of the fixed plate is fixedly connected with a melting injection device through a vertical seat, the bottom of the melting injection device is provided with an upper module, the inside of the upper module is fixedly connected with a side module through a linkage rod, the middle part of the upper surface of the fixed plate is movably sleeved with a lower module through the linkage rod, and the lower module is positioned under the side module;

the device comprises two side modules, wherein the two side modules are mutually symmetrical by taking a central line in the vertical direction of the melting injection device as a symmetrical shaft, the facing surfaces of the two side modules, the lower surface of the upper module and the top of the lower module are in sealing contact with each other pairwise to form a space which is a section mould cavity, the middle part of the front surface of the lower module is fixedly connected with a replacement container, the bottom of the replacement container is communicated with the bottom of the section mould cavity through a through pipe, the volume of pure liquid in the replacement container is one to five times of the volume of the inner part of the section mould cavity, the left side of the inner cavity of the replacement container is fixedly connected with a temperature adjusting device, the temperature adjusting device comprises a temperature adjusting box, a metal ring and a U-shaped resistance wire, the middle part of the inner cavity of the metal ring is fixedly connected with the outer surface of the U-shaped resistance wire, and the bottom end of the U-, a gap exists between the outer surface of the U-shaped resistance wire and the inner surface of the through pipe, the top of the U-shaped resistance wire is fixedly connected with the bottom of the temperature regulating box, and the temperature regulating box is located inside the replacement container.

Optionally, a material feeding cavity tube is formed in the lower module, the top of the material feeding cavity tube is communicated with the bottom of the melting injection device, the bottom of the material feeding cavity tube is communicated with the top of the forming cavity, the length of the material feeding cavity tube is one point and five centimeters, and a central vertical line of the upper surface of the forming cavity in the vertical direction is coincident with a central line of the melting injection device in the vertical direction.

Optionally, the left side and the right side of the side module are both fixedly connected with a mold stripping device, the center lines of the two mold stripping devices in the vertical direction of the module below are mutually symmetrical by taking the center lines as symmetrical axes, the mold stripping device comprises a fixed rod, the right side of the fixed rod is movably sleeved with an arc-shaped clamping rod through an annular sleeve, the arc-shaped clamping rod is provided with a pulley, the left side of the pulley is contacted with the right side of the arc-shaped clamping rod in the lateral direction, a supporting column is movably sleeved on the back surface of the pulley, the left side of the supporting column is fixedly connected with the right side of the upper module, the right side of the side module is fixedly connected with the left side of the arc-shaped clamping rod through an elastic telescopic part, the fixed rod, the elastic telescopic part and the supporting column are parallel to each other in the horizontal direction, the elastic telescopic part is positioned between the support column and the fixed rod, the bottom of the lower module is fixedly connected with a clamping hook, and the bottom end of the arc-shaped clamping rod is clamped with the clamping hook of the lower module.

Optionally, the middle part fixedly connected with regulation and control device of lower module lower surface down, regulation and control device is including leading to a section of thick bamboo, the surface that leads to a section of thick bamboo is provided with cup joint mechanism, cup joint mechanism is including the cover fishplate bar, vertical groove has all been seted up to the both sides of cover fishplate bar, two the equal movable adjustment in inside of vertical groove has the joint piece, one side in opposite directions of two joint pieces respectively with correspond with the left and right sides fixed connection who leads to a section of thick bamboo, the right side fixedly connected with servo motor of cover fishplate bar inner chamber, the latch has all been seted up to the left and right sides that leads to a section of thick bamboo inner chamber, servo motor's output shaft fixedly connected with sector gear, sector gear is located the inside that leads to a section of.

Optionally, the top of lower module is provided with separator, separator is including Z type pole, the three hornblocks of right side fixedly connected with I of Z type pole, the top of three hornblocks I is provided with three hornblocks II, the top of three hornblocks II and the bottom fixed connection of side form piece, the right side fixed connection of elastic shrinkage part and lower module is passed through in the left side of Z type pole, three hornblocks I and three hornblocks II are the same isosceles right triangle of size, three hornblocks II and three hornblocks I are symmetry axis along corresponding contact inclined plane, the through-hole is with the length that is in horizontal interval between the vertical direction siphunculus in through-hole right side for three hornblocks I right angle limit.

The invention provides a three-dimensional injection molding device, which has the following beneficial effects:

1. this three-dimensional injection moulding device, through the replacement container, separator, the siphunculus, cooperation between type die cavity and the attemperator, utilize inside the filling of type die cavity to mould plastics equivalent high concentration pure liquid and occupy the inside volume of type die cavity, and then discharge the inside air of type die cavity, utilize attemperator to keep pure liquid and melting injection moulding liquid to be in the same temperature simultaneously, avoided present cost increase and time growth that causes through the air pump vacuumed condition, be favorable to improving this three-dimensional injection moulding device exhaust effect and reduce the exhaust cost, be favorable to guaranteeing the life of mould simultaneously.

2. This three-dimensional injection moulding device, through the demolding device, lower module, the side module, go up the module and regulate and control the cooperation between the device, after injection moulding product shaping, utilize servo motor and sector gear to drive the lower module on the logical section of thick bamboo and slide down mutually, be convenient for make lower module, side module and last module all with the injection moulding product phase separation, be convenient for with injection moulding product and chamber wall phase separation, the surface atress inequality of avoiding injection moulding product causes the product to receive the damage, utilize the separation simultaneously of chamber wall bottom and side, the injection moulding cycle of product has been shortened, improve this three-dimensional injection moulding device's production rate.

Drawings

FIG. 1 is a schematic front view of the present invention;

FIG. 2 is a side schematic view of a displacement vessel according to the invention;

FIG. 3 is an enlarged view of the demolding device of the present invention;

FIG. 4 is an enlarged view of the structure at A in the present invention;

FIG. 5 is a detailed view of the regulating device of the present invention.

In the figure: 1. a fixing plate; 2. a lower module; 3. a side module; 4. an upper module; 5. a replacement vessel; 6. a linkage rod; 7. a mold stripping device; 71. fixing the rod; 72. a pulley; 73. an arc-shaped clamping rod; 74. an elastic expansion member; 75. a support pillar; 8. a melt injection device; 9. a regulating device; 91. passing through the cylinder; 92. a socket joint mechanism; 921. sleeving and connecting plates; 922. a clamping block; 923. a vertical slot; 93. a servo motor; 94. a sector gear; 10. a linkage rod; 11. a separation device; 111. a Z-shaped rod; 112. a triangular block I; 113. a triangular block II; 114. an elastic contracting member; 115. a through hole; 12. pipe passing; 13. a vertical seat; 14. a molding cavity; 15. a temperature adjusting device; 151. a temperature regulating box; 152. a metal ring; 153. u-shaped resistance wire.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-5, a three-dimensional injection molding device comprises a fixed plate 1, a melting injection device 8 is fixedly connected to the right side of the upper surface of the fixed plate 1 through a vertical seat 13, an upper module 4 is arranged at the bottom of the melting injection device 8, a side module 3 is fixedly connected to the inside of the upper module 4 through a linkage rod 6, a limiting groove i is formed in the upper module 4, the top end of the linkage rod 6 is clamped in the limiting groove i, a lower module 2 is movably sleeved at the middle part of the upper surface of the fixed plate 1 through a linkage rod 10, a limiting groove ii is formed in the lower module 2, the top end of the linkage rod 10 is clamped in the limiting groove ii, the depth of an inner cavity of the limiting groove ii is twice of the depth of the inner cavity of the limiting groove i, and the lower module 2 is located right;

the number of the side modules 3 is two, the two side modules 3 are mutually symmetrical by taking a central line in the vertical direction of the melting injection device 8 as a symmetrical shaft, the facing surfaces of the two side modules 3, the lower surface of the upper module 4 and the top of the lower module 2 are in sealing contact with each other pairwise to form a space which is a die cavity 14, the middle part of the front surface of the lower module 2 is fixedly connected with a replacement container 5, the bottom of the replacement container 5 is communicated with the bottom of the inner cavity of the die cavity 14 through a through pipe 12, the volume of pure liquid in the replacement container 5 is one-point five times of the inner volume of the die cavity 14, the left side of the inner cavity of the replacement container 5 is fixedly connected with a temperature adjusting device 15, the temperature adjusting device 15 comprises a temperature adjusting box 151, a metal ring 152 and a U-shaped resistance wire 153, the middle part of the inner cavity of the metal ring 152 is fixedly connected with the outer surface of the U-shaped resistance wire 153, the bottom, a gap exists between the outer surface of the U-shaped resistance wire 153 and the inner surface of the through pipe 12, the top of the U-shaped resistance wire 153 is fixedly connected with the bottom of the temperature regulating box 151, and the temperature regulating box 151 is positioned inside the replacement container 5.

Wherein, the interior of the lower module 2 is provided with a material passing cavity pipe, the top of the material passing cavity pipe is communicated with the bottom of the melting injection device 8, the bottom of the material passing cavity pipe is communicated with the top of the mould cavity 14, the length of the material passing cavity pipe is one point five centimeters, the central vertical line of the upper surface of the mould cavity 14 in the vertical direction is coincident with the central line of the melting injection device 8 in the vertical direction, the volume inside the mould cavity 14 is occupied by the high-concentration pure liquid with the same injection quantity filled in the mould cavity 14 through the matching among the replacement container 5, the separation device 11, the through pipe 12, the mould cavity 14 and the temperature adjusting device 15, and then the air inside the mould cavity 14 is discharged, meanwhile, the temperature adjusting device 15 is used for keeping the pure liquid and the melting injection liquid at the same temperature, thereby avoiding the cost increase and time increase caused by the existing vacuum pumping state through an air pump, being beneficial to improving the exhaust effect and reducing the exhaust, and simultaneously, the service life of the die is ensured.

Wherein, the left and right sides of the side module 3 are fixedly connected with the mold stripping device 7, the central line of the vertical direction of the module 2 below the two mold stripping devices 7 is symmetrical with each other by a symmetrical axis, the mold stripping device 7 comprises a fixed rod 71, the right side of the fixed rod 71 is movably sleeved with an arc clamping rod 73 through an annular sleeve, the arc clamping rod 73 is provided with a pulley 72, the left side of the pulley 72 is contacted with the right side of the arc clamping rod 73 in the right direction, the back of the pulley 72 is movably sleeved with a supporting column 75, the left side of the supporting column 75 is fixedly connected with the right side of the upper module 4, the right side of the side module 3 is fixedly connected with the left side of the arc clamping rod 73 through an elastic telescopic part 74, the fixed rod 71, the elastic telescopic part 74 and the supporting column 75 are parallel to each other in the horizontal direction, the elastic telescopic part 74 is positioned between the supporting column 75 and the fixed rod 71, the bottom of the lower, utilize lever principle, when side module 3 and lower module 2 slide downwards in opposite directions simultaneously, when the top joint of trace 6 was in the bottommost of I inner chamber of spacing groove, its side module 3 was not at the lapse, and the bump at arc kelly 73 top receives pulley 72 and just makes lower module 2 and arc kelly 73 phase separation simultaneously, is convenient for separate the product after the injection moulding with side module 3.

Wherein, the middle part of the lower surface of the lower module 2 is fixedly connected with a regulating device 9, the regulating device 9 comprises a through cylinder 91, the outer surface of the through cylinder 91 is provided with a sleeve mechanism 92, the sleeve mechanism 92 comprises a sleeve plate 921, both sides of the sleeve plate 921 are respectively provided with a vertical groove 923, the insides of the two vertical grooves 923 are movably regulated with a clamping block 922, the opposite sides of the two clamping blocks 922 are respectively and fixedly connected with the left side and the right side of the through cylinder 91 correspondingly, the depth of the inner cavity of the vertical groove 923 is equal to the depth of the inner cavity of the limiting groove II, the right side of the inner cavity of the sleeve plate 921 is fixedly connected with a servo motor 93, the left side and the right side of the inner cavity of the through cylinder 91 are respectively provided with a clamping tooth, an output shaft of the servo motor 93 is fixedly connected with a sector gear 94, the sector gear 94 is positioned inside the through cylinder 91, the outer surface of the sector gear 94 is engaged with the clamping tooth on the through, be convenient for make lower module 2, side form module 3 and last module 4 all with the injection moulding product phase separation, be convenient for with injection moulding product and chamber wall phase separation, avoid injection moulding product's surface atress inequality to cause the product to receive the damage, utilize mould chamber wall bottom and side to separate simultaneously, shortened the injection moulding cycle of product, improve this three-dimensional injection moulding device's production rate.

Wherein, the top of the lower module 2 is provided with a separating device 11, the separating device 11 comprises a Z-shaped rod 111, the right side of the Z-shaped rod 111 is fixedly connected with a triangular block I112, the top of the triangular block I112 is provided with a triangular block II 113, the top of the triangular block II 113 is fixedly connected with the bottom of the side module 3, the left side of the Z-shaped rod 111 is fixedly connected with the right side of the lower module 2 through an elastic shrinkage component 114, the triangular block I112 and the triangular block II 113 are isosceles right triangles with the same size, the triangular block II 113 and the triangular block I112 are mutually symmetrical along corresponding contact inclined planes as symmetrical axes, the transverse distance between the through hole 115 and the through pipe 12 in the right vertical direction at the right side of the through hole 115 is the length of the right-angle side of the triangular block I112, when the inclined plane of the triangular block II 113 is completely contacted with the inclined plane of the triangular block I112, the triangular block II 113 pushes the triangular block I112 to drive, so as to facilitate the communication between the through pipe 12 and the closed mold cavity 14 and to facilitate the injection of high-concentration pure liquid into the mold cavity 14 to remove air from the closed mold cavity 14.

When the high-concentration pure liquid in the displacement container 5 is still higher than the pure liquid in the feeding cavity, and the pure liquid is kept at the same temperature as the injection molding solution through the U-shaped resistance wire 153 on the temperature regulating box 151 at the same time, the concentration of the high-concentration pure liquid is higher than that of the molten injection molding liquid, and both the high-concentration pure liquid and the molten injection molding liquid are pure substances, and then the high-concentration pure liquid and the molten injection molding liquid are layered in the die cavity 14, and then the molten injection molding liquid is injected into the die cavity 14 through the molten injection device 8, because the molten injection molding liquid is directly contacted with the pure liquid, then the molten injection molding liquid is pushed to the interior of the displacement container 5 again through injecting the pure liquid, at this time, the molten injection molding liquid is completely filled in the die cavity 14, and then the molten injection molding liquid is cooled and solidified, when the die is taken out, the servo motor 93 drives the sector gear 94 to rotate for a half circle, at this time, the through cylinder 91 is driven to slide downwards, the lower die block 2 and the side die block 3 are sequentially driven to move downwards, then the arc clamping rod 73 is driven to slide downwards, the pulley 72 pushes the arc clamping rod 73 to move, then the lower module 2 and the side module 3 are separated and then the solidified product is driven to be separated from the lower module.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a three-dimensional injection moulding device, includes fixed plate (1), its characterized in that: the right side of the upper surface of the fixed plate (1) is fixedly connected with a melting injection device (8) through a vertical seat (13), the bottom of the melting injection device (8) is provided with an upper module (4), the interior of the upper module (4) is fixedly connected with a side module (3) through a linkage rod (6), the middle part of the upper surface of the fixed plate (1) is movably sleeved with a lower module (2) through a linkage rod (10), and the lower module (2) is positioned under the side module (3);

the mold comprises side modules (3), the two side modules (3) are symmetrical with each other by taking a central line in the vertical direction of a melting injection device (8) as a symmetrical axis, the facing surfaces of the two side modules (3), the lower surface of an upper module (4) and the top of a lower module (2) are in pairwise mutual sealing contact to form a space which is a mold cavity (14), the middle part of the front surface of the lower module (2) is fixedly connected with a replacement container (5), the bottom of the replacement container (5) is communicated with the bottom of the inner cavity of the mold cavity (14) through a through pipe (12), the volume of pure liquid in the replacement container (5) is one-point five times of the inner volume of the mold cavity (14), the left side of the inner cavity of the replacement container (5) is fixedly connected with a temperature adjusting device (15), and the temperature adjusting device (15) comprises a temperature adjusting box (151), a metal circular ring (152) and a U-shaped resistance wire (153, the middle part of the inner cavity of the metal circular ring (152) is fixedly connected with the outer surface of a U-shaped resistance wire (153), the bottom end of the U-shaped resistance wire (153) sequentially penetrates through the replacement container (5), the through pipe (12) and the die cavity (14) and is communicated with the bottom of the die cavity (14), a gap exists between the outer surface of the U-shaped resistance wire (153) and the inner surface of the through pipe (12), the top of the U-shaped resistance wire (153) is fixedly connected with the bottom of the temperature regulating box (151), and the temperature regulating box (151) is located inside the replacement container (5).

2. A three-dimensional injection molding apparatus according to claim 1, wherein: the lower die block (2) is internally provided with a material passing cavity pipe, the top of the material passing cavity pipe is communicated with the bottom of the melting injection device (8), the bottom of the material passing cavity pipe is communicated with the top of the die cavity (14), the length of the material passing cavity pipe is one point and five centimeters, and a central vertical line of the upper surface of the die cavity (14) in the vertical direction is superposed with a central line of the melting injection device (8) in the vertical direction.

3. A three-dimensional injection molding apparatus according to claim 1, wherein: the left side and the right side of the side module (3) are fixedly connected with mold stripping devices (7), the central lines of the vertical directions of the modules (2) below the two mold stripping devices (7) are symmetrical with each other by a symmetry axis, each mold stripping device (7) comprises a fixed rod (71), the right side of each fixed rod (71) is movably sleeved with an arc clamping rod (73) through an annular sleeve, each arc clamping rod (73) is provided with a pulley (72), the left side of each pulley (72) is in contact with the right side of each arc clamping rod (73), the back of each pulley (72) is movably sleeved with a supporting column (75), the left side of each supporting column (75) is fixedly connected with the right side of the upper module (4), the right side of the side module (3) is fixedly connected with the left side of each arc clamping rod (73) through an elastic telescopic part (74), and the fixed rods (71), the elastic telescopic parts (74) and the supporting columns (75) are parallel with each other in the, the elastic telescopic part (74) is located between the supporting column (75) and the fixing rod (71), the bottom of the lower module (2) is fixedly connected with a clamping hook, and the bottom end of the arc-shaped clamping rod (73) is clamped with the clamping hook of the lower module (2).

4. A three-dimensional injection molding apparatus according to claim 1, wherein: the middle part fixedly connected with regulation and control device (9) of lower module (2) lower surface, regulation and control device (9) is including leading to a section of thick bamboo (91), the surface that leads to a section of thick bamboo (91) is provided with coupling mechanism (92), coupling mechanism (92) are including cover fishplate bar (921), vertical slot (923) have all been seted up to the both sides of cover fishplate bar (921), two the equal movable regulation in inside of vertical slot (923) has joint piece (922), the opposite side one side of two joint pieces (922) respectively with correspond with the left and right sides fixed connection that leads to a section of thick bamboo (91), the right side fixedly connected with servo motor (93) of cover fishplate bar (921) inner chamber, the latch has all been seted up to the left and right sides that leads to a section of thick bamboo (91) inner chamber, the output shaft fixedly connected with sector gear (94) of servo motor (93), sector gear (94) are located the, the outer surface of the sector gear (94) is meshed with the clamping teeth on the through cylinder (91) in the axial direction.

5. A three-dimensional injection molding apparatus according to claim 1, wherein: the top of the lower module (2) is provided with a separating device (11), the separating device (11) comprises a Z-shaped rod (111), the right side of the Z-shaped rod (111) is fixedly connected with a triangular block I (112), the top of the triangular block I (112) is provided with a triangular block II (113), the top of the triangular block II (113) is fixedly connected with the bottom of the side module (3), the left side of the Z-shaped rod (111) is fixedly connected with the right side of the lower module (2) through an elastic contraction part (114), the triangular block I (112) and the triangular block II (113) are isosceles right triangles with the same size, the triangular block II (113) and the triangular block I (112) are mutually symmetrical along the corresponding contact inclined plane as a symmetrical axis, the transverse distance between the through hole (115) and the through pipe (12) in the vertical direction on the right side of the through hole (115) is the length of the right-angle side of the triangular block I (112).