Support for a base of a blow mould for bottles and method for its production

Abstract

The application discloses a kind of support for blow molding bottle mould base and preparation method thereof, the support is a cylindrical body, with opposite first end and second end;First end is used to be connected with rotating base, and the second end is used to be connected with connecting disc;The wall thickness of cylindrical body is uniformly distributed along the circumferential direction;Cylindrical body includes plastic matrix and rigid reinforcing member, and rigid reinforcing member is embedded in plastic matrix, and central axis is collinear with the central axis of plastic matrix.The application is based on the design of single cylindrical body structure, by the design of coaxial plastic matrix and rigid reinforcing member embedded in plastic matrix, the support has torsional stiffness and buffering damping performance, to ensure that the overall synchronous, stable rotation of rotating base, support and connecting disc, uniformly bear torsional load, effectively improve the quality of bottle blowing, reduce the rate of defective products to 3% or less;Single cylindrical body independent modular design is helpful to the independent disassembly and quick maintenance of support.

Description

Technical Field

[0001] This invention relates to the field of blow molding technology, and in particular to a support component for a blow molding mold base and its preparation method. Background Technology

[0002] In blow molding machines, the support component is a key part that connects the rotating base and the connecting plate. It is used to rigidly connect the connecting plate and the rotating base to form a stable and vibration-resistant high-speed rotating frame foundation.

[0003] In the prior art, the rotating base and the connecting plate are usually connected by multiple spaced rod-shaped bodies as support members, such as the support member with open triangular grooves on both sides disclosed in Chinese Patent CN 221892548 U.

[0004] However, in the process of implementing the technical solution of the present application, the inventors of this application discovered that the above-mentioned technology has at least the following technical problems: when the blow molding machine is running at high speed, the frame foundation composed of the support, the rotating base and the connecting plate vibrates significantly and has poor rotational stability. The support will produce different degrees of torsional deformation after rotation, and the rotation of the connecting plate lags behind the rotating base, affecting the blow molding quality. Summary of the Invention

[0005] This invention provides a support for a blow molding mold base and its manufacturing method, which can solve the above-mentioned problems existing in the operation of blow molding machines using existing spaced rod-shaped support components.

[0006] To solve the above technical problems, the present invention provides a support for a blow molding mold base. The support is a cylindrical body with a first end and a second end opposite to each other. The first end is used to connect with a rotating base, and the second end is used to connect with a connecting plate. The wall thickness of the cylindrical body is uniformly distributed along the circumferential direction. The cylindrical body includes: A plastic matrix, wherein the plastic matrix has a cylindrical structure and is made of fiber-reinforced engineering plastic; and A rigid reinforcement member, which is a cylindrical structure, is embedded in the plastic matrix, and its central axis is collinear with the central axis of the plastic matrix.

[0007] In a preferred embodiment of the present invention, the plastic matrix comprises the following components by weight: 70-90 parts engineering plastic, 15-30 parts reinforcing fiber, 3-5 parts coupling agent, 0.5-1 part antioxidant, and 0.5-1 part lubricant.

[0008] In a preferred embodiment of the present invention, the engineering plastic is selected from at least one of polybutylene terephthalate or high-temperature resistant polyamide.

[0009] In a preferred embodiment of the present invention, the reinforcing fiber is selected from at least one of glass fiber or carbon fiber.

[0010] In a preferred embodiment of the present invention, the length of the reinforcing fiber is greater than or equal to 4 mm.

[0011] In a preferred embodiment of the present invention, the rigid reinforcement is made of precipitation-hardening stainless steel.

[0012] In a preferred embodiment of the present invention, the rigid reinforcement is embedded in the plastic matrix, and both the upper and lower ends of the rigid reinforcement are completely covered by the plastic matrix.

[0013] To solve the above-mentioned technical problems, the present invention also provides a method for preparing a support member for a blow molding mold base, comprising the following steps: (1) Surface pretreatment: A bonding structure is machined on the surface of the rigid reinforcement for mechanical locking with the plastic matrix; (2) Preheating treatment: The rigid reinforcement that has undergone preheating is heated to 150-180°C for preheating treatment; (3) Molding: The preheated rigid reinforcement and the raw material of the plastic matrix are placed into the mold cavity of the rotational molding mold, and then the mold is closed; (4) Rotational molding: The rotational molding mold is placed in the rotational molding machine and rotated under heating conditions. The raw material of the plastic matrix melts and evenly coats the surface of the rigid reinforcement. After cooling and demolding, the support is obtained.

[0014] In a preferred embodiment of the present invention, the bonding structure is at least one of a groove, knurling, or positioning protrusion.

[0015] In a preferred embodiment of the present invention, in step (4), the heating temperature is 230-320℃ and the time is 3-5h; the linear speed of the rotational molding die is 10-30 rpm.

[0016] The beneficial effects of this invention are as follows: The support component for the base of a blow molding bottle and its preparation method, based on the design of a single cylindrical structure, and through the design of a coaxially arranged plastic matrix and a rigid reinforcement embedded in the plastic matrix, enable the support component to have both torsional stiffness and buffering and vibration reduction performance. This ensures that the entire structure consisting of the rotating base, support component and connecting plate rotates synchronously and stably, and evenly bears torsional loads, effectively improving the blow molding quality and reducing the defect rate to below 3%. In addition, the independent modular design of the single cylindrical body facilitates the independent disassembly and assembly and rapid maintenance of the support component. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the connection structure between the support member for the blow molding bottle mold base, the plastic matrix, and the rigid reinforcement member according to the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure of the support member shown. The components in the attached diagram are labeled as follows: 100. Support component; 110. Plastic matrix; 120. Rigid reinforcement component; 200. Rotating base; 300. Connecting plate. Detailed Implementation

[0018] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0019] Example 1 like Figure 1 As shown, this embodiment provides a support member 100 for a blow molding bottle mold base. The support member 100 is a cylindrical body with a first end and a second end opposite to each other. The wall thickness of the cylindrical body is evenly distributed along the circumferential direction. The first end is used to connect with a rotating base 200, and the second end is used to connect with a connecting plate 300.

[0020] The support frame 100 is an independent modular unit that can be disassembled and installed as a whole from the blow molding machine frame, facilitating maintenance and replacement. Furthermore, the wall thickness of the cylindrical body is uniformly distributed along the circumference, ensuring uniform mass distribution of the support 100 during rotation. This guarantees even force distribution in different directions, avoids stress concentration, and improves the consistency of stiffness in all directions, thereby enhancing the rotational stability of the overall structure of the rotating base 200, support 100, and connecting plate 300.

[0021] like Figure 2 As shown, the cylindrical body includes a plastic matrix 110 and a rigid reinforcement 120. The plastic matrix 110 has a cylindrical structure and is made of fiber-reinforced engineering plastic. Specifically, the plastic matrix 110 comprises the following components in parts by weight: The invention comprises 70-90 parts of engineering plastic, wherein the engineering plastic is selected from at least one of polybutylene terephthalate (PBT) or high-temperature resistant polyurethane (PA10T). Using engineering plastic with high rigidity, high strength, and excellent dimensional stability as the matrix, this invention, while meeting the rigidity requirements of the support component, also endows the support component with buffering and vibration damping properties, thereby improving rotational stability.

[0022] 15-30 parts of reinforcing fiber, wherein the length of the reinforcing fiber is greater than or equal to 4 mm, and the reinforcing fiber is selected from at least one of glass fiber or carbon fiber, for enhancing the structural strength and stiffness of the plastic matrix 110.

[0023] 3-5 parts of coupling agent, wherein the coupling agent is a silane coupling agent, used to improve the cross-sectional bonding force between the reinforcing fiber and the engineering plastic.

[0024] Antioxidant 0.5-1 part is used to improve the antioxidant properties of the plastic matrix.

[0025] 0.5-1 part lubricant is used to improve processing performance and facilitate demolding.

[0026] The rigid reinforcement 120 is a cylindrical structure made of precipitation-hardening stainless steel, and is embedded in the plastic matrix 110 with its central axis aligned with the central axis of the plastic matrix 110. The upper and lower end faces of the rigid reinforcement are completely enclosed by the plastic matrix, so that the rigid reinforcement and the plastic matrix form an axial mechanical lock, thereby preventing the rigid reinforcement from coming out of the plastic matrix, increasing the bonding area between the two, so that the load is evenly transmitted and local stress concentration is avoided.

[0027] The precipitation-hardening stainless steel is preferably 17-4PH stainless steel with a yield strength of 1000-1170MPa, which can provide high-strength circumferential support for the plastic matrix 110, effectively resist torsional deformation, and ensure the synchronization accuracy of the rotating base 200 and the connecting plate 300 under high-speed rotation.

[0028] The present invention also provides a method for preparing the support component for the base of the blow-molded bottle, which adopts a rotational molding process and includes the following steps: (1) Surface pretreatment: The rigid reinforcement 120 is processed with knurling, turning or other methods to form a bonding structure for mechanical locking with the plastic matrix. The bonding structure is at least one of knurling, annular groove or positioning protrusion.

[0029] (2) Preheating treatment: The rigid reinforcement 120 with the surface pretreatment completed is placed in a heating furnace and heated to 150-180°C for preheating treatment. Through preheating, the plastic near the rigid reinforcement can be cooled slowly and evenly, thereby fully and evenly covering the rigid reinforcement and improving the interfacial bonding strength.

[0030] (3) Mold insertion: Open the rotational molding mold, first fix the preheated rigid reinforcement 120 in the predetermined position in the mold cavity, then add a predetermined amount of the raw material of the plastic matrix, and close the mold after the material is added; the predetermined amount is calculated and determined according to the target wall thickness and volume of the support 100 to ensure that the plastic matrix completely covers the rigid reinforcement.

[0031] (4) Rotational molding: The rotational molding mold is placed in a rotational molding machine and rotated at a linear speed of 10-30 rpm for 3-5 hours at 230-320℃, so that the raw material of the plastic matrix in the mold cavity melts and fully and evenly covers the surface of the rigid reinforcement. After cooling, the mold is demolded to obtain the support.

[0032] The technical solution of the present invention will be described in detail below through specific embodiments.

[0033] Example 1 This embodiment provides a support for a blow molding die base, the structure of which includes a cylindrical plastic substrate 110 as described above and a rigid reinforcing member 120 embedded inside the plastic substrate.

[0034] The plastic matrix 110 is a glass fiber reinforced PBT material, comprising the following components by weight: 70 parts PBT, 15 parts glass fiber with a length of 4-6 mm, 3 parts silane coupling agent KH-550, 0.5 parts antioxidant 10100, and 0.5 parts zinc stearate.

[0035] The rigid reinforcement 120 is made of 17-4PH precipitation hardening stainless steel, supplied in H900 condition, and has a yield strength of 1100 MPa.

[0036] The plastic substrate 110 and the rigid reinforcement 120 are both cylindrical structures and are coaxially arranged. The wall thickness of the support 100 formed by them is evenly distributed along the circumferential direction and is 12mm.

[0037] Its preparation method is as follows: (1) Knurling is used to process the surface of the rigid reinforcement 120 as a bonding structure for mechanical locking with the plastic matrix; (2) Place the rigid reinforcing part 120 with knurled outer surface into a heating furnace and preheat it to 160°C; (3) Open the rotational molding mold, first fix the preheated rigid reinforcement 120 in the predetermined position in the mold cavity, then add the predetermined amount of the raw material of the plastic matrix according to the above formula, and close the mold; (4) Under heating conditions, the rotational molding mold is rotated at a linear speed of 20 rpm, the heating temperature is 240℃, and the heating time is 4h. The raw material of the plastic matrix in the mold cavity melts and fully and evenly covers the surface of the rigid reinforcement. After cooling, the mold is demolded to obtain the support.

[0038] Example 2 This embodiment provides a support for a blow molding die base, the structure of which includes a cylindrical plastic matrix as described above and a rigid reinforcement embedded inside the plastic matrix.

[0039] The plastic matrix 110 is a carbon fiber reinforced PA10T material, comprising the following components by weight: PA10T 80 parts, carbon fiber with a length of 4-6mm 22 parts, silane coupling agent KH-550 4 parts, antioxidant 1010 0.8 parts, zinc stearate 0.8 parts.

[0040] The rigid reinforcement 120 is made of 17-4PH precipitation hardening stainless steel, supplied in H900 condition, and has a yield strength of 1100 MPa.

[0041] The plastic substrate 110 and the rigid reinforcement 120 are both cylindrical structures and are coaxially arranged. The wall thickness of the support 100 formed by them is evenly distributed along the circumferential direction and is 12mm.

[0042] Its preparation method is as follows: (1) An annular groove is machined on the surface of the rigid reinforcement 120 by turning process as a bonding structure for mechanical locking with the plastic matrix; (2) Place the rigid reinforcing member 120 with an annular groove on its outer surface into a heating furnace and preheat it to 160°C; (3) Open the rotational molding mold, first fix the preheated rigid reinforcement 120 in the predetermined position in the mold cavity, then add the predetermined amount of the raw material of the plastic matrix according to the above formula, and close the mold; (4) Under heating conditions, the rotational molding mold is rotated at a linear speed of 20 rpm, the heating temperature is 310℃, and the heating time is 5h. The raw material of the plastic matrix in the mold cavity melts and fully and evenly covers the surface of the rigid reinforcement. After cooling, the mold is demolded to obtain the support.

[0043] Example 3 The difference from Example 1 is that the plastic matrix 110 is a glass fiber reinforced PBT material, comprising the following components by weight: 90 parts PBT, 30 parts glass fiber with a length of 4-6 mm, 3 parts silane coupling agent KH-550, 0.5 parts antioxidant 1010, and 0.5 parts zinc stearate.

[0044] A positioning protrusion is machined on the surface of the rigid reinforcement 120 using a turning process to serve as a bonding structure for mechanical locking with the plastic matrix.

[0045] Everything else is the same as in Example 1. Comparative Example 1 The difference from Embodiment 1 is that the support member 100 does not have a rigid reinforcement member 120 embedded in it; otherwise, it is the same as the embodiment.

[0046] The supports of Examples 1-3 and Comparative Example 1 were connected to the rotating base 200 and the connecting plate 300, respectively. Under the same operating conditions, the supports of Examples 1-3 had higher rotational stiffness and lower vibration levels. The connecting plate 300 rotated synchronously with the rotating base 200 without lag, resulting in good preform appearance quality and a scrap rate of less than 3%. The supports were also free from twisting. The support of Comparative Example 1 showed obvious torsional deformation. Under rotational conditions, the blow molding machine frame vibrated slightly, and the rotation of the connecting plate 300 lagged behind that of the rotating base 200, resulting in a preform scrap rate of over 30%.

[0047] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A support component for a blow molding bottle mold base, characterized in that, The support is a cylindrical body with a first end and a second end opposite to each other; the first end is used to connect with the rotating base, and the second end is used to connect with the connecting plate; the wall thickness of the cylindrical body is uniformly distributed along the circumferential direction. The cylindrical body includes: The plastic matrix has a cylindrical structure and is made of fiber-reinforced engineering plastic; A rigid reinforcement member, which is a cylindrical structure, is embedded in the plastic matrix, and its central axis is collinear with the central axis of the plastic matrix.

2. The support member according to claim 1, characterized in that, The plastic matrix comprises the following components by weight: 70-90 parts engineering plastic, 15-30 parts reinforcing fiber, 3-5 parts coupling agent, 0.5-1 part antioxidant, and 0.5-1 part lubricant.

3. The support member according to claim 2, characterized in that, The engineering plastic is selected from at least one of polybutadiene terephthalate or high-temperature resistant polyamide.

4. The support member according to claim 2, characterized in that, The reinforcing fiber is selected from at least one of glass fiber or carbon fiber.

5. The support member according to claim 4, characterized in that, The length of the reinforcing fiber is greater than or equal to 4 mm.

6. The support member according to claim 1, characterized in that, The rigid reinforcement is made of precipitation-hardening stainless steel.

7. The support member according to claim 1, characterized in that, The rigid reinforcement is embedded in the plastic matrix, and both the upper and lower ends of the rigid reinforcement are completely covered by the plastic matrix.

8. A method for preparing a support member for a blow molding bottle mold base as described in any one of claims 1-7, characterized in that, Includes the following steps: (1) Surface pretreatment: A bonding structure is machined on the surface of the rigid reinforcement for mechanical locking with the plastic matrix; (2) Preheating treatment: The rigid reinforcement that has undergone preheating is heated to 150-180°C for preheating treatment; (3) Molding: The preheated rigid reinforcement and the raw material of the plastic matrix are placed into the mold cavity of the rotational molding mold, and then the mold is closed; (4) Rotational molding: The rotational molding mold is placed in the rotational molding machine and rotated under heating conditions. The raw material of the plastic matrix melts and evenly coats the surface of the rigid reinforcement. After cooling and demolding, the support is obtained.

9. The method according to claim 8, characterized in that, The bonding structure is at least one of groove, knurling, or positioning protrusion.

10. The method according to claim 8, characterized in that, In step (4), the heating temperature is 230-320℃ and the time is 3-5h; the linear speed of the rotational molding die is 10-30 rpm.

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