Bottle blank internal and external heating blow molding mold

Abstract

The utility model discloses a bottle blank inside and outside heating blow molding mould which comprises a mounting frame and two opening and closing moulds arranged on the mounting frame, and further comprises a heating assembly arranged on the mounting frame and used for heating the inside of a bottle blank, and the heating assembly comprises a driving piece arranged on the side, close to a pipe pushing air cylinder, of the mounting frame. The driving part is connected with stretching pipes through a connecting frame, the multiple stretching pipes are arranged, and each heating sleeve is provided with an adjusting assembly used for adjusting the density of the corresponding flexible spiral electric heating pipe. According to the bottle blank inside and outside heating blow molding mold disclosed by the utility model, through the arrangement of the heating assembly, the temperature of a bottle blank heating area is adjusted and controlled by utilizing the adjusting assembly while the inside and the outside of a bottle blank are heated at the same time, so that the bottle blank is adaptive to the thickness difference of a bottle blank structure, and the heating uniformity of the bottle blank is further improved; therefore, the internal and external heating effect on the bottle blank is further improved.

Description

Technical Field

[0001] This utility model relates to the field of blow molding molds for bottle preforms, specifically to blow molding molds for heating the inside and outside of bottle preforms. Background Technology

[0002] Plastic granules are used as raw materials for making bottles. After being heated and compressed in a mold, they form a preform. The preform is then placed into a blow molding mold, and air is injected into it. The preform expands due to the air, thus forming the shape of the cavity inside the blow molding mold.

[0003] Currently, blow molding is commonly used to heat the preform, transferring heat to the preform within the blow molding cavity to reach the blow molding temperature. However, heating the preform via the blow molding mold results in uneven heating of the outer layer first, followed by heat transfer to the inner layer, which can lead to defects and scrap during blow molding. To address this issue, existing technology CN215661800U, a preform internal and external heating blow molding mold and a one-step injection stretch blow molding machine, uses a heated pre-blown molding mold to heat the outer layer of the preform. Since the tension rod is a heated tension rod with a heating function, it heats the inner layer (preform cavity) of the preform, thereby heating the preform. The inner and outer layers of the preform are heated simultaneously to ensure uniform heating throughout. While this internal and external heating improves the molding quality of the bottle, the preform's inherent structure results in thickness variations across different parts during the molding process. For example, to ensure the bottle's strength and stability in subsequent use, the shoulder and bottom need to be thickened. This increased thickness lengthens the heat transfer path and increases thermal resistance. Within the same heating time, thicker areas absorb less heat and heat up more slowly, making it difficult to reach the same temperature as thinner parts of the bottle. This uneven heating makes it difficult to ensure consistent heating across the entire preform, thus affecting the internal and external heating effect.

[0004] Therefore, there is an urgent need for blow molding dies that heat the preform inside and out to solve the above problems. Utility Model Content

[0005] To achieve the above objectives, this utility model provides the following technical solution: a blow molding die for heating bottle preform internally and externally, including a mounting frame and two opening and closing molds disposed on the mounting frame. The two opening and closing molds are provided with multiple cavities. The mounting frame is provided with opening and closing mold supports on opposite sides. The sides of the two opening and closing molds that are far apart from each other are respectively connected to the opposite ends of the two opening and closing mold supports. The mounting frame is provided with multiple push tube cylinders on one side. Each push tube cylinder has a high-pressure blowing pipe installed on its drive rod. The assembly also includes a heating component disposed on the mounting frame for internal heating of the bottle preform.

[0006] The heating assembly includes a drive unit disposed on the side of the mounting frame near the push tube cylinder. The drive unit is connected to a stretching tube via a connecting frame. Multiple stretching tubes are arranged in a row, and each stretching tube corresponds to a multiple pre-blown bottle forming cavity. Multiple high-pressure blowing pipes correspond to multiple stretching tubes, and each stretching tube passes through each high-pressure blowing pipe. A heating sleeve is fixedly connected inside each stretching tube. A flexible spiral electric heating tube is sleeved on the side wall of each heating sleeve. Each heating sleeve is provided with an adjustment component for adjusting the density of each flexible spiral electric heating tube.

[0007] The adjustment assembly includes two adjustment rings sleeved on the side wall of the heating jacket. The two adjustment rings are respectively connected to both ends of the flexible spiral electric heating tube. The two adjustment rings are provided with fixing components for fixing to the flexible spiral electric heating tube. The heating jacket is provided with a power cord. One end of the power cord passes through the connecting frame and is connected to an external power source. The other end of the power cord is connected to a power socket. The power socket is connected to multiple taps. The end of each tap away from the power socket is respectively connected to the wire of each flexible spiral electric heating tube. The side wall of the heating jacket has a strip-shaped hole. The end of each tap near the adjustment ring is slidably connected to the strip-shaped hole.

[0008] The end of the connecting frame near the stretching tube is fixedly connected to a threaded tube, and the end of the threaded tube near the connecting frame is threadedly connected to the threaded tube.

[0009] The fixing component includes a U-shaped groove on the side of the adjusting ring near the connecting frame. The U-shaped groove is slidably connected to two locking rods arranged symmetrically. The two locking rods have wedge-shaped surfaces on the side near the heating sleeve. The U-shaped groove is provided with a pushing component for pushing the two locking rods.

[0010] The pushing assembly includes a pushing plate slidably connected to the U-shaped groove. Two pushing rods are fixedly connected to the side of the pushing plate near the two locking rods. The ends of the two pushing rods away from the pushing plate are respectively connected to the two locking rods. A threaded rod is threadedly connected to the side wall of the adjusting ring. One end of the threaded rod is connected to the pushing plate, and the other end of the threaded rod has a regular hexagonal rotating hole. The U-shaped groove is provided with a guide assembly for guiding the movement of the pushing plate.

[0011] The guiding assembly includes two guide tubes that are fixedly connected to the bottom wall of the U-shaped groove and arranged symmetrically. The two guide tubes are slidably connected to guide rods, and one end of the two guide rods is connected to the push plate.

[0012] The heating sleeve is fitted with a heat insulation sleeve on the inner side wall of the stretching tube, and the heat insulation sleeve can be replaced with different lengths according to the heating area.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] This utility model relates to a blow molding die for heating the bottle preform inside and out. By setting up a heating component, it can simultaneously heat the inside and outside of the bottle preform, while using an adjustment component to regulate and control the temperature of the heating area of ​​the bottle preform, so as to adapt to the thickness difference of the bottle preform structure, thereby improving the uniformity of heating the bottle preform and further improving the heating effect of the inside and outside of the bottle preform. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the internal structure of the heating component of this utility model;

[0016] Figure 2 This is a schematic diagram showing the positional relationship between the two opening and closing molds, the mounting frame, and the opening and closing mold support of this utility model;

[0017] Figure 3 This is a schematic diagram showing the positional relationship between the heating component and the high-pressure air blowing pipe of this utility model;

[0018] Figure 4 This is a schematic diagram of the heating component structure of this utility model;

[0019] Figure 5 This is a schematic diagram of the fixing component structure of this utility model;

[0020] Figure 6 This is a schematic diagram of the internal structure of the adjustment component of this utility model.

[0021] In the diagram: 101, mounting bracket; 102, opening and closing mold; 103, opening and closing mold support; 104, push tube cylinder; 105, high-pressure air blowing pipe; 201, driving component; 202, connecting frame; 203, stretching tube; 204, flexible spiral electric heating tube; 205, threaded tube; 206, heating jacket; 301, adjusting ring; 302, power cord; 303, power socket; 304, tap line; 305, strip hole; 401, U-shaped groove; 402, locking rod; 403, wedge-shaped surface; 501, push plate; 502, push rod; 503, threaded rod; 601, guide tube; 602, guide rod; 7, heat insulation jacket. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Example 1

[0024] Please see Figures 1-5 The bottle preform internal and external heating blow molding die shown in the figure includes a mounting frame 101 and two opening and closing molds 102 disposed on the mounting frame 101. The two opening and closing molds 102 are provided with multiple cavities. The mounting frame 101 is provided with opening and closing mold supports 103 on opposite sides. The opposite sides of the two opening and closing molds 102 are respectively connected to the opposite ends of the two opening and closing mold supports 103. The mounting frame 101 is provided with multiple push tube cylinders 104 on one side. Each push tube cylinder 104 has a high-pressure blowing pipe 105 installed on its drive rod. The die also includes a heating component disposed on the mounting frame 101 for internal heating of the bottle preform.

[0025] The heating assembly includes a drive unit 201 disposed on the side of the mounting frame 101 near the push tube cylinder 104. The drive unit 201 is connected to a stretching tube 203 via a connecting frame 202. Multiple stretching tubes 203 are arranged in a row, and each stretching tube 203 corresponds to a multiple pre-blown bottle forming cavity. Multiple high-pressure blowing pipes 105 correspond to each stretching tube 203, and each stretching tube 203 passes through each high-pressure blowing pipe 105. A heating sleeve 206 is fixedly connected inside each stretching tube 203. A flexible spiral electric heating tube 204 is sleeved on the side wall of each heating sleeve 206. Each heating sleeve 206 is provided with an adjustment component for adjusting the density of each flexible spiral electric heating tube 204.

[0026] The adjustment assembly includes two adjustment rings 301 sleeved on the side wall of the heating sleeve 206. The two adjustment rings 301 are respectively connected to both ends of the flexible spiral electric heating tube 204. The two adjustment rings 301 are provided with fixing components for fixing the flexible spiral electric heating tube 204. The heating sleeve 206 is provided with a power cord 302. One end of the power cord 302 passes through the connecting frame 202 and is connected to an external power source. The other end of the power cord 302 is connected to a power socket 303. The power socket 303 is connected to multiple taps 304. The end of each tap 304 away from the power socket 303 is respectively connected to the wire of each flexible spiral electric heating tube 204. The side wall of the heating sleeve 206 is provided with a strip hole 305. The end of each tap 304 near the adjustment ring 301 is slidably connected to the strip hole 305.

[0027] It should be noted that by setting up the heating components, the bottle preform can be heated both inside and out simultaneously. At the same time, the temperature of the heating area of ​​the bottle preform can be adjusted and controlled by the adjustment components to adapt to the thickness difference of the bottle preform structure, thereby improving the uniformity of the heating of the bottle preform and thus further improving the heating effect of the bottle preform inside and out.

[0028] It is worth noting that the opening and closing mold 102 can be heated to the required temperature by means of oil heating, electric heating, etc., and then the heat is transferred to the preform located in the pre-blown bottle forming cavity through the opening and closing mold 102, so that the preform reaches the blow molding temperature.

[0029] It should be emphasized that the main components of the flexible spiral electric heating tube 204 are the heating core, the insulation layer and the flexible outer sheath. It can be bent into various shapes and can closely fit the surface of irregular objects to be heated, so as to achieve uniform heating.

[0030] Please see Figure 1 In the figure, the end of the connecting frame 202 near the stretching tube 203 is fixedly connected to the threaded tube 205, and the end of the threaded tube 205 near the connecting frame 202 is threadedly connected to the threaded tube 205.

[0031] It should be noted here that the threaded tube 205 is used to connect to the tension tube 203, thereby facilitating the disassembly of the tension tube 203 and providing operational convenience for the adjustment of the adjustment component.

[0032] Working principle: During blow molding, the drive component 201 (for the specific structure and working principle of the drive component 201, please refer to CN215661800U, Bottle Preform Internal and External Heating Blow Molding Mold and One-Step Injection Stretching Blow Molding Integrated Machine, which will not be elaborated here) drives the stretching tube 203 to move downward and extend into the inner cavity of the bottle preform. High-pressure gas is blown into the inner cavity of the bottle preform from the blow nozzle end of the bottle preform, causing the bottle preform to expand and stretch. At the same time, the stretching tube 203 moves downward to push the bottle preform to stretch. The stretching tube 203 plays the role of guiding the stretching (extension) of the bottle preform, making the bottle preform easier to extend and form. The bottle preform is stretched evenly and the forming effect is good. After blow molding is completed, the drive component 201 is used again to drive the stretching tube 203 to move upward and leave the bottle preform.

[0033] Among them, the two opening and closing molds 102 are mature existing technologies, mainly used for heating the preform and guiding the preform to stretch (extend). Therefore, the specific structure and principle of the two opening and closing molds 102 will not be described in detail here.

[0034] Meanwhile, the two opening and closing molds 102 can be heated to the required temperature by oil heating, electric heating or other means, and then the heat is transferred to the preform in the pre-blown bottle forming cavity through the two opening and closing molds 102, so that the preform reaches the blow molding temperature.

[0035] In the specific blow molding process, the two opening and closing molds 102 open, the pre-blown bottle forming cavity opens, and the preform is placed in the pre-blown bottle forming cavity. The two opening and closing molds 102 close, with the blown end of the preform facing upward and at least partially extending out of the upper sidewalls of the two opening and closing molds 102. The preform body is located in the pre-blown bottle forming cavity. At the same time, the stretching tube 203 adapts to extend into the inner cavity of the preform from the blown end, and heats the outer layer of the preform through the two opening and closing molds 102. Since the stretching tube 203 is equipped with multiple flexible spiral electric heating tubes 204 inside, the multiple flexible spiral electric heating tubes 204 heat the outer layer of the preform. Under the heating action of 04, the inner layer (inner cavity) of the preform is heated, thereby realizing the simultaneous heating of the inner and outer layers of the preform. During the blow molding process, high-pressure gas is blown into the inner cavity of the preform from the blow nozzle end. Under the stretching and heating action of the stretch tube 203, the preform expands and extends to form the bottle body. The finished product has good quality and low scrap rate (the heating process and working principle of the preform are only briefly described here. For the specific working principle, please refer to CN215661800U, Preform Inner and Outer Heating Blow Molding Mold and One-Step Injection Stretching Blow Molding Integrated Machine, which will not be elaborated on here).

[0036] Meanwhile, due to the inherent structure of the preform, there are thickness differences in different parts of the preform. Therefore, during the internal heating of the preform, two adjusting rings 301 can be used to stretch and compress the flexible spiral electric heating tube 204. Under the action of the fixing component, the two adjusting rings 301 are fixed to the side wall of the heating sleeve 206, thereby adjusting the density of the flexible spiral electric heating tube 204. By changing the density of the flexible spiral electric heating tube 204, the temperature of the preform heating area can be adjusted and controlled to adapt to the thickness differences of the preform structure, thereby improving the uniformity of preform heating and further enhancing the internal and external heating effect of the preform.

[0037] Example 2

[0038] Please see Figure 5 and Figure 6 This embodiment further illustrates Example 1. The fixing component shown in the figure includes a U-shaped groove 401 opened on the side of the adjusting ring 301 near the connecting frame 202. The U-shaped groove 401 is slidably connected to two locking rods 402 arranged symmetrically. The two locking rods 402 are provided with a wedge-shaped surface 403 on the side near the heating sleeve 206. The U-shaped groove 401 is provided with a pushing component for pushing the two locking rods 402.

[0039] It should be noted that: by setting the fixing component, the adjusting ring 301 is locked and limited under the action of the pushing component and the guiding component, thereby fixing the adjusting ring 301 and the heating sleeve 206, thus ensuring the morphological stability of the flexible spiral electric heating tube 204 after adjustment.

[0040] Please see Figure 5 The push assembly shown in the figure includes a push plate 501 slidably connected to a U-shaped groove 401. Two push rods 502 are fixedly connected to the side of the push plate 501 near the two locking rods 402. The ends of the two push rods 502 away from the push plate 501 are respectively connected to the two locking rods 402. A threaded rod 503 is threadedly connected to the side wall of the adjusting ring 301. One end of the threaded rod 503 is connected to the push plate 501, and the other end of the threaded rod 503 is provided with a regular hexagonal rotating hole. The U-shaped groove 401 is provided with a guide assembly for guiding the movement of the push plate 501.

[0041] It should be noted here that by pushing the component, the two locking levers 402 can be moved.

[0042] It is worth noting that the adjusting ring 301 has a threaded hole on its side wall, the threaded rod 503 is threaded into the threaded hole, and after the threaded rod 503 has rotated, the end of it that is away from the push plate 501 does not exceed the side wall of the adjusting ring 301.

[0043] Please see Figure 5 The guide assembly shown in the figure includes two guide tubes 601 that are symmetrically arranged and fixedly connected to the bottom wall of the U-shaped groove 401. The two guide tubes 601 are slidably connected to guide rods 602, and one end of the two guide rods 602 is connected to the push plate 501.

[0044] It should be noted here that the image does not show the wiring assembly, which is used to guide and limit the movement of the push plate 501.

[0045] Working principle: When fixing the adjusting ring 301, firstly, the threaded rod 503 is rotated using an Allen wrench. During the rotation of the threaded rod 503, the threaded engagement between the threaded rod 503 and the adjusting ring 301, along with the guiding action of the guide assembly, drives the two locking rods 402 at one end of the push plate 501 to move. During the movement of the two locking rods 402, when the wedge-shaped surface 403 on one side of the two locking rods 402 abuts against the side wall of the heating sleeve 206, the rotation of the threaded rod 503 can be stopped. Then, under the abutting action of the wedge-shaped surface 403 on the side wall of the two locking rods 402, the adjusting ring 301 is locked and limited, thereby fixing the adjusting ring 301 and the heating sleeve 206, thus ensuring the stability of the flexible spiral electric heating tube 204 after adjustment.

[0046] Example 3

[0047] Please see Figure 1This embodiment is a further explanation of other embodiments. In the figure, the heating sleeve 206 is located inside the side wall of the stretching tube 203 and is fitted with a heat insulation sleeve 7. The heat insulation sleeve 7 can be replaced with different lengths according to the heating area.

[0048] It should be noted that the heat insulation sleeve 7 is used to isolate the area where the stretching tube 203 does not contact the preform, thereby reducing heat loss and improving the utilization rate of heat. In addition, the replaceable length of the heat insulation sleeve 7 makes it easy to adapt to the adjustment range of the flexible spiral electric heating tube 204.

[0049] It is worth noting that the regulating ring 301 is also made of heat insulation material, thereby reducing temperature interference between different temperature zones. The regulating ring 301 and the heat insulation sleeve 7 are made of materials including but not limited to ceramic fiber cloth or high silica cloth. At the same time, the tap line 304 is also made of heat insulation material.

[0050] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A bottle blank internal and external heating blow molding mold, comprising: a mounting frame (101) and two opening and closing molds (102) arranged on the mounting frame (101), a plurality of cavities are arranged in the two opening and closing molds (102), and opposite sides of the mounting frame (101) are provided with opening and closing mold supports (103); one side of the mounting frame (101) is provided with a plurality of push tube cylinders (104), and a high-pressure blowing pipe (105) is arranged on the drive rod of each push tube cylinder (104); characterized in that it further comprises: a heating assembly arranged on the mounting frame (101) for internally heating the bottle blank; the heating assembly comprises a driving member (201) arranged on one side of the mounting frame (101) close to the push tube cylinder (104), the driving member (201) is connected with a stretching pipe (203) through a connecting frame (202), a plurality of stretching pipes (203) are arranged, and a plurality of stretching pipes (203) are arranged one by one corresponding to a plurality of pre-blowing bottle forming cavities; a plurality of high-pressure blowing pipes (105) are arranged one by one corresponding to a plurality of stretching pipes (203), and each stretching pipe (203) is arranged in each high-pressure blowing pipe (105); each stretching pipe (203) is fixedly connected with a heating sleeve (206), each heating sleeve (206) is sleeved with a flexible spiral electric heating pipe (204) on the side wall, and each heating sleeve (206) is provided with an adjusting assembly for adjusting the density of each flexible spiral electric heating pipe (204); the adjusting assembly comprises two adjusting rings (301) sleeved on the side wall of the heating sleeve (206), the two adjusting rings (301) are connected with two ends of the flexible spiral electric heating pipe (204) respectively, the two adjusting rings (301) are provided with a fixing assembly for fixing the flexible spiral electric heating pipe (204), the heating sleeve (206) is provided with a power line (302), one end of the power line (302) penetrates through the connecting frame (202) and is connected with an external power supply, the other end of the power line (302) is connected with a power supply seat (303), the power supply seat (303) is connected with a plurality of tapping lines (304), one end of each tapping line (304) away from the power supply seat (303) is connected with the electric wire of each flexible spiral electric heating pipe (204) respectively, and a strip-shaped hole (305) is arranged on the side wall of the heating sleeve (206). One end of each tapping line (304) close to the adjusting ring (301) is slidably connected to the strip-shaped hole (305).

2. The inside and outside heating blow mold for a preform according to claim 1, characterized in that: One end of the connecting frame (202) close to the stretching pipe (203) is fixedly connected with a threaded pipe (205), and one end of the threaded pipe (205) close to the connecting frame (202) is threadedly connected to the threaded pipe (205).

3. The inside and outside heating blow mold for a preform according to claim 2, characterized in that: The fixed assembly includes a U-shaped groove (401) opened in the adjusting ring (301) close to the side of the connecting frame (202), the U-shaped groove (401) is slidably connected with two symmetrically arranged locking rods (402), the side close to the heating jacket (206) of the two locking rods (402) is provided with a wedge surface (403), and the U-shaped groove (401) is provided with a pushing assembly for pushing the two locking rods (402).

4. The inside and outside heating blow mold for a preform according to claim 3, characterized in that: The pushing assembly includes a pushing plate (501) slidably connected with the U-shaped groove (401), the side close to the two locking rods (402) of the pushing plate (501) is fixedly connected with two pushing rods (502), the ends away from the pushing plate (501) of the two pushing rods (502) are respectively connected with the two locking rods (402), the side wall of the adjusting ring (301) is threadedly connected with a threaded rod (503), one end of the threaded rod (503) is connected with the pushing plate (501), the other end of the threaded rod (503) is provided with a hexagonal rotating hole, and the U-shaped groove (401) is provided with a guiding assembly for guiding the movement of the pushing plate (501).

5. The inside and outside heating blow mold for a preform according to claim 4, characterized in that: The guiding assembly includes two symmetrically arranged guiding pipes (601) fixedly connected with the bottom wall of the U-shaped groove (401), the two guiding pipes (601) are slidably connected with guiding rods (602), and one end of the two guiding rods (602) is connected with the pushing plate (501).

6. The inside and outside heating blow mold for a preform according to claim 5, characterized in that: The heating jacket (206) is sleeved with a heat insulation sleeve (7) on the inner side wall of the stretching pipe (203), and the heat insulation sleeve (7) can be replaced with different lengths according to the heating area.

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