A multi-petal undercut rubber-metal joint mold and product molding method

Abstract

A multi-petal inverted rubber-metal joint mold includes an upper mold, a middle mold, and a lower mold. The middle mold is arranged between the upper mold and the lower mold. A glue injection barrel is arranged between the upper mold and the middle mold. A groove is provided at the bottom of the glue injection barrel, and an upper insert is provided in the groove. The middle mold has a through mounting hole, and a petal-type petal mold and a partition are provided in the mounting hole of the middle mold. A circular groove is provided in the lower mold, and a lower insert is provided in the circular groove. The petal-type outer shell, petal mold, and partition are accurately positioned by internal positioning protrusions and external positioning rings. The middle mold is used for circumferential positioning, and the upper mold, lower mold, glue injection plug, and glue injection barrel are used for vertical positioning, thereby ensuring that the product shape will not be deformed as a whole and improving the product qualification rate. The petal mold, partition, upper insert, and lower insert in the mold are arranged as a petal structure, which makes the assembly and demoulding of the mold very convenient and efficient.

Description

Technical Field

[0001] The present invention relates to a mold and a product molding method, and in particular to a multi-petal undercut rubber-metal joint mold and a product molding method. Background Art

[0002] Currently, the mold design for "Big Neck" rubber-metal joints mostly uses a transfer mold injection vulcanization method. Furthermore, the product itself has a multi-petal outer shell structure with undercuts. This leads to issues such as easy scratching of the entire mold core, difficulty in demolding, and high manufacturing costs during the molding process. Furthermore, after vulcanization, the product's dimensional shrinkage deviation is large, and the eccentricity value varies significantly.

[0003] Through domestic search, it was found that the following patents have similarities with the present invention:

[0004] The invention with application number CN201410141583.X and titled “Fully automatic demoulding injection molding mold” relates to the field of plastic molding technology, and specifically relates to a fully automatic demoulding injection molding mold, which is sequentially provided with a movable mold base plate, a push rod push plate, a push rod fixed plate, a movable mold plate, a fixed mold plate combined with the movable mold plate, and a fixed mold base plate from bottom to top, a core is provided in the movable mold plate, a cavity combined with the core is provided in the fixed mold plate, and after the cavity and the core are combined, a one-mold two-cavity structure is formed inside thereof, which can simultaneously inject two inclined plate multi-rib plastic parts, the two cavities have the same structure and are arranged in reverse symmetry, and a transverse flow channel leading to the two cavities is provided between the two cavities. The beneficial effects of the present invention are that the fully automatic demoulding injection molding mold of the present invention reliably realizes fully automatic demoulding, improves the production efficiency of plastic parts, and has stable quality. At the same time, due to the simplified structure, the manufacturing difficulty and cost of the mold are reduced, and the service life and precision of the mold are improved.

[0005] The invention with application number CN201711104487.8 and titled “A method for manufacturing a rail vibration damper and an automatic demoulding mold of a mother-and-child structure” discloses a method for manufacturing a rail vibration damper and an automatic demoulding mold of a mother-and-child structure. The automatic demoulding mold of the mother-and-child structure of the rail vibration damper includes a mother mold and a child mold installed on the mother mold. The mother mold includes a glue plug mounting plate, a glue plug, a glue injection cylinder, a lower mold frame, a lower mold plate, a push-pull plate, a push rod and an upper mold frame located above the lower mold frame. The child mold includes a child mold upper mold core and a child mold lower mold core; the child mold upper mold core is installed on the upper mold frame, and the child mold lower mold core is installed on the lower mold frame. The mother mold is universal and the child mold can be replaced, so that when manufacturing different series of rail vibration dampers, only the child mold needs to be replaced. A push rod-type demoulding mechanism is used to realize automatic separation of the product and the mold. The present invention reduces mold development costs and shortens mold development cycles from the design source, and adopts a push-rod demoulding mechanism to achieve automatic separation of the product and the mold, thereby reducing the production cost of the track vibration absorber and improving the production efficiency of the track vibration absorber.

[0006] The structures in the above patents are very different from those in the present application, and none of the above patents have a mold structure in which the upper and lower inserts, petal molds and partitions all adopt a petal-type parting structure, nor do they have the beneficial technical effects of sequential demolding after vulcanization molding, which is efficient, orderly and will not scratch the core shaft. Summary of the Invention

[0007] The technical problem to be solved by the present invention is: how to make the mold of the split-type rubber metal joint quickly and effectively close the mold and inject glue, and quickly and effectively demould the molten rubber after cooling, so as to complete the product manufacturing with high efficiency and high quality.

[0008] In response to the above problems, the technical solution proposed in the present invention is: a multi-petal inverted rubber metal joint mold, including an upper mold, a middle mold and a lower mold, the middle mold is arranged between the upper mold and the lower mold, a glue injection cylinder is arranged between the upper mold and the middle mold, a groove is opened at the bottom of the glue injection cylinder, an upper insert is arranged in the groove, a through mounting hole is opened in the middle mold, a petal mold and a partition are arranged in the mounting hole of the middle mold, a circular groove is opened in the lower mold, and a lower insert is arranged in the circular groove.

[0009] An annular groove is opened on the upper surface of the glue injection cylinder, so that a columnar center column is formed on the inner side of the annular groove, and an external glue injection hole is opened at the bottom of the annular groove to pass through the glue injection cylinder, and the external glue injection holes are evenly distributed in the circumferential direction of the annular groove.

[0010] It also includes a glue injection plug, which is in the shape of a round tube and is placed in the annular groove. The upper mold presses the glue injection plug tightly in the annular groove so that the glue injection plug blocks all external glue injection holes.

[0011] The upper insert is a petal-type insert with a through upper positioning hole in the middle of the upper insert and a waist-shaped groove in the circumferential direction outside the upper positioning hole. Each waist-shaped groove has an inner glue injection hole that passes through the upper insert on the side close to the upper positioning hole, and the diameter of the inner glue injection hole gradually decreases from top to bottom.

[0012] The lower insert is a petal insert. An upwardly protruding, annular inner positioning convex block is arranged in the middle of the upper surface of the lower insert. A mounting hole penetrating the inner positioning convex block and the upper insert is provided on the inner positioning convex block.

[0013] The upper surface of the lower insert is also provided with an annular outer positioning ring and a strip-shaped expansion groove. The outer positioning ring is arranged on the outside of the inner positioning protrusion, and the height of the outer positioning ring is less than the height of the inner positioning protrusion; the expansion groove is arranged on the outside of the outer positioning ring, and the length direction of the expansion groove is the radial direction of the outer positioning ring.

[0014] Preferably, the thickness of the inner side of the partition is smaller than the thickness of the outer side of the partition, and a step surface is formed at the boundary between the inner and outer sides of the partition; the inner side of the bottom of the partition is provided with a groove corresponding to the inner positioning protrusion and outer positioning ring of the lower insert, and the outer sides of the inner positioning protrusion and outer positioning ring of the lower insert are both engaged in the groove of the partition.

[0015] A product molding method using a multi-petal undercut rubber-metal joint mold includes assembling the mold, injecting molten rubber into the mold, and demolding the product after the rubber cools. The mold assembly steps include:

[0016] S1. First install the split lower insert into the lower mold, then install the mandrel onto the lower insert;

[0017] S2. Sequentially place the petal-type jacket and partitions on the upper surface of the lower panel;

[0018] S3. Close the petal mold;

[0019] S4. Assemble the split upper insert and mandrel;

[0020] S5. Assemble the middle mold and inject the rubber cylinder;

[0021] S6. Place the rubber plug and upper mold in sequence to complete the mold installation.

[0022] Preferably, the injection of molten rubber into the mold is carried out by opening a through injection hole on the injection cylinder and the upper insert, injecting the molten rubber into the mold through the injection hole of the injection cylinder and the upper insert, so that the molten rubber is injected into the gap between the core shaft and the outer sleeve, thereby vulcanizing the core shaft and the outer sleeve into a whole with the rubber, and forming a product after cooling.

[0023] Preferably, after the product is cooled and formed, the demoulding step includes:

[0024] S1. Remove the upper mold, injection plug, and injection cylinder in sequence;

[0025] S2. Pry and remove the middle mold;

[0026] S3. Remove the petal-shaped mold;

[0027] S4. Remove the split-petal upper insert;

[0028] S5. Take out the product and the lower insert in turn to obtain the product and complete demoulding.

[0029] The beneficial technical effects of the present invention are as follows: inner positioning protrusions and outer positioning rings are provided on the lower surface of the upper insert and the upper surface of the lower insert, and the petal-type outer shell, petal mold, and partition are precisely positioned by the inner positioning protrusions and the outer positioning ring. The middle mold is used for circumferential positioning, and the upper mold, lower mold, injection plug, and injection cylinder are used for vertical positioning, thereby ensuring that the overall shape of the product will not be deformed and improving the product qualification rate. The petal mold, partition, upper insert, and lower insert in the mold are arranged as a petal-type structure, which makes the assembly and demolding of the mold very convenient and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the overall structure of Example 1;

[0031] Figure 2 This is a schematic diagram of the overall structure decomposition of Example 1;

[0032] Figure 3 It is a vertical cross-sectional schematic diagram of embodiment 1;

[0033] Figure 4 for Figure 1 Schematic diagram of the structure of the hidden upper die;

[0034] Figure 5 for Figure 4 The structural diagram of the glue injection cylinder and the glue injection plug is hidden in the figure;

[0035] Figure 6 for Figure 5 Schematic diagram of the structure of the hidden middle mold and lower mold;

[0036] Figure 7 for Figure 6 Schematic diagram of the structural decomposition;

[0037] Figure 8 The structure of the glue injection cylinder of Example 1 is shown as follows Figure 1 ;

[0038] Figure 9 The structure of the glue injection cylinder of Example 1 is shown as follows Figure 2 ;

[0039] Figure 10 Schematic diagram of the structure of the upper insert of Example 1;

[0040] Figure 11 Schematic diagram of the structure of the lower insert of Example 1;

[0041] Figure 12 Schematic diagram of the structure of the lower mold of Example 1;

[0042] Figure 13 Schematic diagram of the structure of the partition of Example 1;

[0043] In the figure: upper mold 1, glue injection plug 2, glue injection cylinder 3, annular groove 31, center column 32, external glue injection hole 33, first layer groove 34, second layer groove 35, third layer groove 36, petal mold 4, outer sleeve 5, rubber 6, partition 7, notch 71, step surface 72, upper insert 8, upper positioning hole 81, waist-shaped groove 82, inner glue injection hole 83, lower insert 9, outer positioning ring 91, inner positioning protrusion 92, telescopic groove 93, core shaft 10, middle mold 11, lower mold 12, circular groove 121, lower positioning hole 122. DETAILED DESCRIPTION

[0044] The present invention will be further described below with reference to the embodiments and accompanying drawings: Example 1

[0045] like Figures 1 to 3 as well as Figures 5 to 7 As shown, the mold of the multi-petal inverted rubber 6 metal joint includes an upper mold 1, a glue plug 2, a glue injection cylinder 3, a petal mold 4, a partition 7, an upper insert 8, a lower insert 9, a middle mold 11 and a lower mold 12. The outer sleeve 5, rubber 6 and core shaft 10 are components of the metal joint and are also the products made after demolding in this embodiment. The middle mold 11 is arranged between the upper mold 1 and the lower mold 12, the glue injection cylinder 3 is arranged between the upper mold 1 and the middle mold 11, and the glue plug 2 is placed in the glue injection cylinder 3. A groove is provided at the bottom of the glue injection cylinder 3, and an upper insert 8 is provided in the groove. The petal mold 4 and the partition 7 are provided in the mounting hole of the middle mold 11. A circular groove 121 is provided in the lower mold 12, and a lower insert 9 is provided in the circular groove 121. The core shaft 10 passes through the mounting hole of the middle mold 11, and the petal outer sleeve 5 is also arranged in the mounting hole of the middle mold 11, and the outer side of the outer sleeve 5 is tightly attached to the inner side of the petal mold 4.

[0046] like Figure 4 、 Figure 5 、 Figure 8 and Figure 9 As shown, an annular groove 31 is formed on the upper surface of the injection barrel 3, with a cylindrical center post 32 formed inside the annular groove 31. The injection plug 2 is tubular and placed in the annular groove 31, with the injection plug 2 sleeved onto the center post 32. External injection holes 33 are formed at the bottom of the annular groove 31, extending through the injection barrel 3. The external injection holes 33 are evenly distributed around the circumference of the annular groove 31. The upper mold 1 presses the injection plug 2 into the annular groove 31, blocking all the external injection holes 33.

[0047] The lower surface of the injection cylinder 3 is provided with three layers of grooves, namely a first layer of grooves 34, a second layer of grooves 35, and a third layer of grooves 36. The third layer of grooves 36 is provided in the second layer of grooves 35, and the second layer of grooves 35 is provided in the first layer of grooves 34. The third layer of grooves 36 is formed by hollowing out the center column 32 of the injection cylinder 3. The first layer of grooves 34 covers the middle mold 11, and the first layer of grooves 34 and the upper end of the middle mold 11 are loosely matched. The second layer of grooves 35 covers the upper insert 8, and the second layer of grooves 35 and the insert are loosely matched. The third layer of grooves 36 covers the core shaft 10, and the third layer of grooves 36 and the upper end of the core shaft 10 are loosely matched.

[0048] like Figure 2 、 Figure 8 and Figure 10 As shown, the upper insert 8 is a split-petal insert. In this embodiment, the upper insert 8 is divided into four independent petals. A through upper positioning hole 81 is provided in the middle of the upper insert 8. A waist-shaped groove 82 is provided in the circumferential direction of the outer side of the upper positioning hole 81. Each waist-shaped groove 82 is provided with an inner glue injection hole 83 that runs through the upper insert 8 on the side near the upper positioning hole 81. The inner glue injection holes 83 gradually decrease in diameter from top to bottom. In this embodiment, there are six inner glue injection holes 83 on the upper insert 8, and the outer sleeve 5, the petal mold 4 and the partition 7 are all three-petal. Each outer sleeve 5, the partition 7, the core shaft 10, the upper insert 8 and the lower insert 9 respectively form a small enclosed space, and each small enclosed space is connected to two inner glue injection holes 83.

[0049] like Figures 11 to 13 As shown, the lower insert 9 is a split-petal insert. In this embodiment, the lower insert 9 and the upper insert 8 are symmetrical in structure, and the lower insert 9 is also divided into four independent petals. An upwardly protruding, annular inner positioning projection 92 is located in the center of the upper surface of the lower insert 9. The inner positioning projection 92 has a mounting hole extending through the inner positioning projection 92 and the upper insert 8. The upper surface of the lower insert 9 is also provided with an annular outer positioning ring 91 and a strip-shaped expansion slot 93. The outer positioning ring 91 is located outside the inner positioning projection 92 and is shorter than the inner positioning projection 92. The expansion slot 93 of both the upper insert 8 and the lower insert 9 is located outside the outer positioning ring 91, and the length of the expansion slot 93 is radially aligned with the outer positioning ring 91. Without the expansion slot 93, the molten rubber 6 would easily form a depression after cooling and shrinking. With the expansion slot 93, the molten rubber 6 flows into the expansion slot 93, and the product shape is restored after the rubber 6 cools and shrinks.

[0050] The upper insert 8 and the lower insert 9 are symmetrical in structure. The lower surface of the upper insert 8 is also provided with an inner positioning protrusion 92 and an outer positioning ring 91. The thickness of the inner side of the partition 7 is less than the thickness of the outer side of the partition 7. A step surface 72 with an L-shaped cross section is formed at the boundary between the inner and outer sides of the partition 7. The inner sides of the top and bottom of the partition 7 are provided with notches 71 corresponding to the inner positioning protrusion 92 and the outer positioning ring 91 of the lower insert 9. The outer sides of the inner positioning protrusion 92 and the outer positioning ring 91 of the upper insert 8 and the lower insert 9 are both engaged in the notches 71 of the partition 7. The inner positioning protrusion 92 and the outer positioning ring 91 are pressed against the notches 71 on the inner side of the partition 7, limiting the position of the partition 7 in the radial direction.

[0051] When a multi-petal undercut rubber-metal joint mold is used to form a product, the mold is first assembled, and then molten rubber is injected into the mold. After the rubber is cooled, the product is demoulded and taken out. The assembly steps of the mold include:

[0052] S1. First, install the split lower insert 9 into the lower mold 12, and then install the mandrel 10 onto the lower insert 9;

[0053] S2. Sequentially place the petal-type jacket 5 and the partition 7 on the upper surface of the lower panel 9;

[0054] S3. The petal-type mold 4 is closed;

[0055] S4. Assemble the split-type upper insert 8 and the mandrel 10;

[0056] S5. Assemble the mold 11 and inject the plastic cartridge 3;

[0057] S6. The rubber plug 2 and the upper mold 1 are sequentially injected to complete the mold installation.

[0058] The molten rubber 6 is injected into the mold by opening a through injection hole on the injection cylinder 3 and the upper insert 8, and injecting the molten rubber 6 into the mold through the injection hole of the injection cylinder 3 and the upper insert 8, so that the molten rubber 6 is injected into the gap between the core shaft 10 and the outer sleeve 5, thereby using the rubber 6 to vulcanize the core shaft 10 and the outer sleeve 5 into a whole, and forming a product after cooling.

[0059] After the product is cooled and formed, the demoulding steps include:

[0060] S1. Remove the upper mold 1, injection plug 2, and injection cylinder 3 respectively;

[0061] S2. Pry and remove the middle mold 11;

[0062] S3. Remove the petal-type mold 4;

[0063] S4. Remove the petal-shaped upper insert 8;

[0064] S5. Take out the product and the lower insert 9 in sequence to obtain the product and complete demoulding.

[0065] Obviously, without departing from the principles of the present invention, several improvements or modifications should be considered as within the scope of protection of the present invention.

Claims

1. A multi-petal undercut rubber metal joint mold, comprising an upper mold, a middle mold and a lower mold, wherein the middle mold is arranged between the upper mold and the lower mold, characterized in that: A glue injection cylinder is provided between the upper mold and the middle mold, a groove is provided at the bottom of the glue injection cylinder, an upper insert is provided in the groove, a through mounting hole is provided in the middle mold, a petal mold and a partition are provided in the mounting hole of the middle mold, a circular groove is provided in the lower mold, and a lower insert is provided in the circular groove; the upper insert is a petal insert, a through upper positioning hole is provided in the middle of the upper insert, a waist-shaped groove is provided in the circumferential direction of the outer side of the upper positioning hole, and an inner glue injection hole that passes through the upper insert is provided on the side of each waist-shaped groove close to the upper positioning hole, and the aperture of the inner glue injection hole gradually decreases from top to bottom; the lower insert is a petal insert, and an upwardly protruding, annular inner positioning convex is provided in the middle of the upper surface of the lower insert The block has an inner positioning protrusion with a mounting hole passing through the inner positioning protrusion and the upper insert; the upper surface of the lower insert is also provided with an annular outer positioning ring and a strip-shaped expansion groove, the outer positioning ring is arranged on the outer side of the inner positioning protrusion, and the height of the outer positioning ring is less than the height of the inner positioning protrusion; the expansion groove is arranged on the outer side of the outer positioning ring, and the length direction of the expansion groove is the radial direction of the outer positioning ring; the thickness of the inner side of the partition is less than the thickness of the outer side of the partition, and a step surface is formed at the boundary between the inner and outer sides of the partition; the inner side of the bottom of the partition is provided with a notch corresponding to the inner positioning protrusion and the outer positioning ring of the lower insert, and the outer sides of the inner positioning protrusion and the outer positioning ring of the lower insert are both engaged in the notch of the partition.

2. A multi-petal undercut rubber-metal joint mold according to claim 1, characterized in that: An annular groove is opened on the upper surface of the glue injection cylinder, so that a columnar center column is formed on the inner side of the annular groove, and an external glue injection hole is opened at the bottom of the annular groove to pass through the glue injection cylinder, and the external glue injection holes are evenly distributed in the circumferential direction of the annular groove.

3. The multi-petal undercut rubber-metal joint mold according to claim 2, characterized in that: It also includes a glue injection plug, which is in the shape of a round tube and is placed in the annular groove. The upper mold presses the glue injection plug tightly in the annular groove so that the glue injection plug blocks all external glue injection holes.

4. A product molding method using the multi-petal undercut rubber-metal joint mold according to claim 1, characterized in that: First, assemble the mold, then inject molten rubber into the mold, and then demould the product after the rubber cools down. The mold assembly steps include: S1. First install the split lower insert into the lower mold, then install the mandrel onto the lower insert; S2. Sequentially place the petal-type jacket and partitions on the upper surface of the lower panel; S3. Close the petal mold; S4. Assemble the split upper insert and mandrel; S5. Assemble the middle mold and inject the rubber cylinder; S6. Place the rubber plug and upper mold in sequence to complete the mold installation.

5. The product forming method according to claim 4, characterized in that: The molten rubber is injected into the mold by opening a through injection hole on the injection cylinder and the upper insert, injecting the molten rubber into the mold through the injection hole of the injection cylinder and the upper insert, so that the molten rubber is injected into the gap between the core shaft and the outer sleeve, thereby vulcanizing the core shaft and the outer sleeve into a whole with the rubber, and forming a product after cooling.

6. The product forming method according to claim 4 or 5, characterized in that: After the product is cooled and formed, the demoulding steps include: S1. Remove the upper mold, injection plug, and injection cylinder in sequence; S2. Pry and remove the middle mold; S3. Remove the petal-shaped mold; S4. Remove the split-petal upper insert; S5. Take out the product and the lower insert in turn to obtain the product and complete demoulding.

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