Plastic bottle blank laser heating device and plastic bottle forming production line

Abstract

The invention relates to the technical field of plastic bottle blank forming, and discloses a plastic bottle blank laser heating device and a plastic bottle forming production line. The plastic bottle blank laser heating device comprises a conveying assembly, a laser heating assembly and a laser heating assembly, a laser beam emitted by the laser array assembly at least completely irradiates the height direction of the plastic bottle blank, and the wavelength of the laser beam is 1700-1880 nm; and the rotation driving assembly and the laser array assembly are correspondingly installed, and the rotation driving assembly is matched with the installation rotary disc so that the installation rotary disc can carry the plastic bottle blanks to rotate when passing through the laser array assembly area. The infrared absorption peak of the plastic bottle blank is concentrated near 1700-1880 nm, and the wavelengths of the laser beams are correspondingly set, so that when the laser beams irradiate the plastic bottle blank, the energy of the laser beams can be directly absorbed by the plastic bottle blank, and the energy utilization rate is increased.

Description

Technical Field

[0001] The invention relates to the technical field of plastic bottle preform molding, and in particular to a plastic bottle preform laser heating device and a plastic bottle molding production line. Background Art

[0002] Plastic bottle packaging occupies an important position in many fields, especially in the beverage and pharmaceutical industries. As the main packaging form, it has a large output and a wide range of applications. The manufacturing process of plastic bottles usually involves heating the preform to a viscous plastic state and then forming it through blow molding. The quality and speed of this heating link are key factors affecting the quality and output of the molded bottle.

[0003] In the field of traditional plastic preform heating technology, halogen lamp heating and microwave heating are two common methods. Halogen lamp heating has many disadvantages. Its radiation directionality is poor and the preform absorption rate is low, which can easily lead to problems such as uneven surface temperature of the preform, large temperature difference between the inside and outside, uneven internal stress, and low thermal efficiency. Although the microwave heating method can achieve uniform temperature inside and outside the preform and reasonable internal stress distribution with the help of the high penetration of microwaves, this method has complex equipment, high cost, and complex radiation leakage prevention design, and it is difficult to perform zone temperature control.

[0004] In order to overcome the defects in the above-mentioned technology, laser heating is usually used in the prior art to heat plastic bottle preforms. The laser heating method has high heating rate, low energy consumption, fast response speed, easy control and integration, etc., so it can be applied to plastic bottle preform blowing. However, in industrial applications, in order to obtain better quality of bottle preforms and further expand the scope of application, it is necessary to control the temperature of plastic bottle preforms in different zones to achieve different temperature distributions in the vertical direction of the bottle preforms. Due to the poor thermal conductivity of plastics, it is difficult to ensure the uniformity of the temperature of the inner and outer walls during the short laser heating process, resulting in the problem that the plastic bottle preforms after laser heating are prone to cracking or partial whitening in the subsequent blow molding process, which is difficult to meet the high quality requirements of plastic bottles. Summary of the invention

[0005] In view of this, the present invention provides a plastic bottle preform laser heating device and a plastic bottle molding production line to solve the problem in the prior art that the plastic bottle preform obtained by laser heating is prone to cracking or partial whitening during the subsequent blow molding process.

[0006] In a first aspect, the present invention provides a laser heating device for a plastic bottle blank, comprising:

[0007] A conveying assembly, on which a mounting turntable is mounted, and the plastic preforms are suitable for mounting on the mounting turntable;

[0008] A laser array assembly, the laser beam emitted by which completely irradiates at least the height direction of the plastic bottle blank, and the wavelength of the laser beam is 1700nm to 1880nm;

[0009] A rotary drive assembly is installed corresponding to the laser array assembly, and the rotary drive assembly cooperates with the mounting turntable to make the mounting turntable rotate with the plastic bottle blank when passing through the laser array assembly area.

[0010] When the laser heating device for plastic preforms is working, the plastic preforms are installed on the mounting turntable, and the conveying assembly conveys the plastic preforms downstream through the mounting turntable. When the plastic preforms are aligned with the laser array assembly, the rotary drive assembly cooperates with the mounting turntable to drive the mounting turntable to drive the plastic preforms to rotate, and at the same time, the laser beam emitted by the laser array assembly irradiates the plastic preforms. Plastic preforms are usually made of materials such as polyethylene terephthalate (PET), and the infrared absorption peak of plastic preforms is concentrated around 1700nm~1880nm. By setting the wavelength of the laser beam to 1700nm~1880nm, when the laser beam irradiates the plastic preforms, the energy of the laser beam can be directly absorbed by the plastic preforms, thereby improving energy utilization. Moreover, by rotating the plastic bottle preform, the plastic bottle preform can uniformly absorb the energy from the laser beam in the circumferential direction, thereby realizing the direct absorption of the laser beam energy by the plastic bottle preform and then realizing the increase of the temperature of the plastic bottle preform itself, which can ensure the uniformity of the temperature of the plastic bottle preform in the circumferential direction and can also realize the increase of the temperature of the plastic bottle preform in the height direction to different gradients, which can greatly improve the molding quality of subsequent blow molding of the plastic bottle preform.

[0011] In an optional embodiment, the wavelength of the laser beam is 1710nm. Plastic preforms are usually made of polyethylene terephthalate (PET), polypropylene (PP), polylactic acid (PLA) or a PET / 2% nylon mixture, which has a high absorption rate for infrared light with a wavelength of 1710nm, allowing the preform to absorb laser energy more efficiently, quickly heat up to the required temperature, improve heating efficiency, shorten heating time, and help improve production efficiency. In addition, lasers of this wavelength can achieve uniform heating of the preform, avoid local overheating or insufficient heating, and ensure the quality of the molded bottle.

[0012] In an optional embodiment, the laser array assembly includes a laser mounting plate and a laser group mounted on the laser mounting plate, wherein a plurality of laser groups are arranged at intervals along the conveying direction of the conveying assembly, and each of the laser groups includes at least one laser body arranged at intervals along the height direction of the laser mounting plate.

[0013] During the conveying process of plastic preforms, multiple groups of lasers irradiate and heat the preforms in turn. The laser bodies at different heights in each laser group can heat different height areas of the preforms. By setting multiple groups of lasers at intervals along the conveying direction, the preforms can be gradually heated during the conveying process, avoiding problems such as uneven temperature or excessive thermal stress caused by one-time heating. The laser bodies arranged at intervals along the height direction in each group can realize zoned temperature control at different positions in the vertical direction of the preforms, meet the different temperature requirements of the preforms at different height areas, improve the accuracy and controllability of heating, and thus improve the quality and performance of the molded bottles. At the same time, the structural design of the laser array assembly is conducive to improving the heating efficiency and meeting the needs of industrial continuous mass production.

[0014] In an optional embodiment, the laser array assembly further includes:

[0015] The mounting platform is fixedly mounted with a first adjustment shaft, a second adjustment shaft is slidably mounted on the first adjustment shaft, a third adjustment shaft is slidably mounted on the second adjustment shaft, the first adjustment shaft, the second adjustment shaft and the third adjustment shaft are arranged perpendicular to each other, and the laser mounting plate is fixedly mounted on the third adjustment shaft. By adjusting the relative positions of the first adjustment shaft, the second adjustment shaft and the third adjustment shaft, the displacement adjustment of the laser mounting plate in the three-dimensional direction of space can be achieved, thereby adjusting the irradiation position and angle of the laser, so that the laser can accurately irradiate the designated area of ​​the plastic bottle blank, more accurately adjust the irradiation position of the laser, ensure that the laser energy can be efficiently transmitted to various parts of the bottle blank, achieve a uniform and accurate heating effect, and improve the heating quality and production efficiency.

[0016] In an optional embodiment, the conveying assembly further includes: a supporting track on which a conveying chain is slidably mounted, and the mounting turntable is rotatably mounted on the conveying chain; and a conveying drive member, which cooperates with the conveying chain to drive the conveying chain to carry the mounting turntable to move along the supporting track. The conveying drive member cooperates with the conveying chain to drive the conveying chain to move along the supporting track, thereby driving the mounting turntable mounted on the supporting track and the plastic preforms to move in a predetermined direction, and sequentially transporting the preforms to the heating station and the next production link. The supporting track provides support for the conveying chain, ensures the stability of the conveying chain during movement, and prevents the preforms from shaking or deflecting during transportation.

[0017] In an optional embodiment, the rotary drive assembly includes a drive chain, and a matching gear is provided on the mounting turntable, and the drive chain is suitable for meshing with the matching gear. When the drive chain moves under the drive of the power source, the mounting turntable and the plastic bottle blank thereon are driven to rotate through meshing transmission with the matching gear, so that the bottle blank can be heated evenly during the heating process. The meshing transmission mode of the drive chain and the matching gear has high transmission accuracy and torque transmission capacity, which can ensure that the mounting turntable rotates at a stable speed, so that the plastic bottle blank can be uniformly irradiated by the laser during the heating process, avoiding local overheating or insufficient heating, improving the uniformity and consistency of heating, and thus improving the quality and performance of the molded bottle.

[0018] In an optional embodiment, the rotary drive assembly further includes at least two driving toothed discs, at least one of which is equipped with a rotary drive member, the driving chain is circulated and installed on a plurality of the driving toothed discs, and the driving toothed discs are meshed with the driving chain. The rotary drive member drives one of the driving toothed discs to rotate, thereby driving the driving chain to circulate, and the driving chain meshes with the matching gear on the mounting turntable to drive the mounting turntable to rotate. The rotation speed of the mounting turntable can be adjusted according to the rotation speed of the driving toothed disc driven by the rotary drive member to adapt to different production speeds and preform rotation requirements, further improving the stability and uniformity of the preform rotation during the heating process, and ensuring the heating quality.

[0019] In an optional embodiment, the light beam emitted by the laser array assembly is square-conical. When the square-conical light beam is irradiated on the plastic bottle blank, a light spot of a specific shape and size can be formed on the surface of the bottle blank, thereby achieving uniform heating of the bottle blank. The square-conical light beam has good energy distribution uniformity and light spot shape controllability. Compared with the traditional circular light spot, the square-conical light spot can better match the shape and size of the plastic bottle blank, making the laser energy more evenly distributed on the surface of the bottle blank, avoiding the problem of uneven heating caused by excessive or low local energy. At the same time, the edge of the square-conical light beam is clearer, which is conducive to achieving precise heating of the edge area of ​​the bottle blank, improving the heating quality and the appearance quality of the molded bottle.

[0020] In an optional embodiment, a feeding mechanism is further included, which is installed upstream of the laser array assembly. The feeding mechanism includes a flip driving member and a feeding gripper. The feeding gripper is installed at the driving end of the flip driving member. The flip driving member is suitable for driving the feeding gripper to flip and feed. During the feeding process, the flip driving member drives the feeding gripper to flip, grabs the plastic preform from the feeding position, and flips the plastic preform to place it upside down on the mounting turntable on the conveying assembly, thereby completing the feeding operation of the preform.

[0021] In a second aspect, the present invention further provides a plastic bottle forming production line, which has the plastic bottle preform laser heating device of the present invention, and a blow molding device is further arranged downstream of the plastic bottle preform laser heating device. Because the plastic bottle forming production line includes the plastic bottle preform laser heating device, it has the same effect as the plastic bottle preform laser heating device, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic structural diagram of a laser heating device for a plastic bottle blank provided in an embodiment of the present invention.

[0024] Figure 2 A schematic structural diagram of the coordinated installation of a transmission assembly and a rotation drive assembly provided in an embodiment of the present invention.

[0025] Figure 3 A schematic structural diagram of the cooperative installation of the first adjustment shaft, the second adjustment shaft and the third adjustment shaft provided in an embodiment of the present invention.

[0026] Figure 4 A schematic diagram of the structure of the laser beam provided by an embodiment of the present invention corresponding to the height direction of the plastic bottle blank.

[0027] Figure 5 A schematic diagram of the structure of the laser beam provided by an embodiment of the present invention corresponding to the horizontal direction of the plastic bottle blank.

[0028] Figure 6 A schematic structural diagram of a laser array assembly provided in an embodiment of the present invention.

[0029] Figure 7 A schematic structural diagram of a laser array assembly provided in another embodiment of the present invention.

[0030] Explanation of the reference numerals: 1. Conveying assembly; 101. Mounting turntable; 102. Supporting track; 103. Conveying chain; 104. Conveying drive member; 2. Laser array assembly; 201. Laser mounting plate; 202. Laser group; 2021. Laser body; 203. Mounting table; 204. First adjusting shaft; 205. Second adjusting shaft; 206. Third adjusting shaft; 3. Rotary driving assembly; 301. Matching gear; 302. Driving chain; 303. Driving gear disc; 4. Feeding mechanism; 401. Flipping drive member; 402. Feeding gripper; 5. Plastic bottle blank. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0032] Combine the following Figures 1 to 7 , describing an embodiment of the present invention.

[0033] According to an embodiment of the present invention, on the one hand, a plastic bottle preform laser heating device is provided, which aims to solve the problem of uneven heating and low efficiency of plastic bottle preform 5 in the prior art, and improve the heating quality and production efficiency. The plastic bottle preform laser heating device includes a conveying component 1, a laser array component 2 and a rotating drive component 3. Among them, a mounting turntable 101 is installed on the conveying component 1, and the plastic bottle preform 5 is suitable for being installed on the mounting turntable 101. The laser beam emitted by the laser array component 2 completely irradiates the height direction of the plastic bottle preform 5 at least, and the wavelength of the laser beam is 1700nm~1880nm. The rotating drive component 3 is installed corresponding to the laser array component 2. When the mounting turntable 101 runs to the area where the laser array component 2 is located, the rotating drive component 3 can drive the mounting turntable 101 to rotate with the plastic bottle preform 5, thereby ensuring that the plastic bottle preform 5 can achieve a uniform heating effect during the heating process.

[0034] When the laser heating device for plastic preforms is in normal working state, the plastic preform 5 is first installed on the mounting turntable 101, and then the conveying component 1 conveys the plastic preform 5 to the downstream direction through the mounting turntable 101. When the plastic preform 5 moves to a position aligned with the laser array component 2 along with the conveying component 1, the rotary drive component 3 starts to work, driving the mounting turntable 101 to drive the plastic preform 5 to rotate. At the same time, the laser beam emitted by the laser array component 2 accurately irradiates the surface of the plastic preform 5. Due to the infrared absorption peak characteristics of the plastic preform 5 itself, it is mainly concentrated near the specific band of 1700nm-1880nm, so the energy carried by the laser beam can be efficiently and directly absorbed by the plastic preform 5. Through this rotary heating method, the plastic preform 5 can uniformly absorb the energy of the laser beam in the circumferential direction, thereby realizing a uniform increase in its own temperature, which not only ensures the uniformity of the temperature distribution, but also can form a reasonable temperature gradient in the height direction, thereby improving the quality and performance of the subsequent blow molding products.

[0035] Specifically, the wavelength of the laser beam used in this embodiment is 1710nm. The plastic bottle blank 5 is usually made of polyethylene terephthalate (PET), polypropylene (PP), polylactic acid (PLA) or PET / 2% nylon mixture, and has a high absorption rate for infrared light with a wavelength of 1710nm, which can make the bottle blank absorb laser energy more efficiently, quickly heat up to the required temperature, improve heating efficiency, shorten heating time, and help improve production efficiency. In addition, the wavelength laser can achieve uniform heating of the bottle blank, avoid local overheating or insufficient heating, and ensure the quality of the molded bottle. In some other embodiments, the wavelength of the laser beam can be adjusted and optimized accordingly according to the different materials of the plastic bottle blank 5 used in actual production. For example, if the plastic bottle blank 5 uses other special materials or the material ratio changes, a matching laser wavelength can be selected to ensure that the laser energy can be efficiently absorbed by the bottle blank, achieve the best heating effect, and meet the special needs of different material bottle blanks during the heating process.

[0036] In one embodiment, the laser array assembly 2 includes a laser mounting plate 201 and a laser group 202 mounted on the laser mounting plate 201. The laser groups 202 are arranged at intervals along the conveying direction of the conveying assembly 1, and there are multiple groups of laser groups 202. Each group of laser groups 202 includes at least one laser body 2021 arranged at intervals along the height direction of the laser mounting plate 201. In the process of conveying the plastic bottle blank, multiple groups of laser groups 202 can irradiate and heat the bottle blank in turn. The laser bodies 2021 at different height positions in each group of laser groups 202 can achieve targeted and precise heating of different height areas of the bottle blank, meeting the differentiated requirements for temperature distribution of the bottle blank in different height directions. In this embodiment, if Figure 6 As shown, three groups of laser groups 202 are arranged at intervals, and three groups of laser bodies 2021 are arranged at intervals along the height direction in each group of laser groups 202. The edges of the laser beams emitted by two adjacent groups of laser bodies 2021 are exactly aligned, so that the laser beams irradiated on the plastic bottle blank 5 will neither overlap nor have gaps. The linear spot powers emitted by the three groups of laser bodies 2021 at the top, middle and bottom are different. Under the same heating station, different temperature distributions can be obtained in the vertical direction of the plastic bottle blank. In some other embodiments, such as Figure 7 As shown, three groups of laser groups 202 are arranged at intervals, and only one group of laser bodies 2021 is arranged in each group of laser groups 202. The three groups of laser bodies 2021 are arranged at intervals along the conveying direction of the conveying assembly 1 in the horizontal direction, and are arranged at intervals along the height direction of the preform body in the height direction. At different stations, the linear spot power emitted by each group of laser bodies 2021 is different. When the plastic preform passes through multiple heating stations, different temperature distributions can be obtained in the vertical direction of the plastic preform.

[0037] During the conveying process of the plastic preform, multiple groups of laser groups 202 irradiate and heat the preform in turn, and the laser bodies 2021 at different height positions in each group of laser groups 202 can realize the heating of different height areas of the preform. By arranging multiple groups of laser groups 202 at intervals along the conveying direction, the preform can be gradually heated during the conveying process, avoiding problems such as uneven temperature or excessive thermal stress caused by one-time heating. The laser bodies 2021 arranged at intervals along the height direction in each group can realize the zoned temperature control of different positions in the vertical direction of the preform, meet the different temperature requirements of the preform in different height areas, improve the accuracy and controllability of heating, and thus improve the quality and performance of the molded bottle. At the same time, the structural design of the laser array assembly 2 is conducive to improving the heating efficiency and meeting the needs of industrial continuous mass production.

[0038] Furthermore, the laser array assembly 2 also includes a mounting platform 203, on which a first adjustment shaft 204 is fixedly mounted, a second adjustment shaft 205 is slidably mounted on the first adjustment shaft 204, a third adjustment shaft 206 is slidably mounted on the second adjustment shaft 205, the first adjustment shaft 204, the second adjustment shaft 205 and the third adjustment shaft 206 are arranged perpendicular to each other, and the laser mounting plate 201 is fixedly mounted on the third adjustment shaft 206. By adjusting the relative positions of the first adjustment shaft 204, the second adjustment shaft 205 and the third adjustment shaft 206, the displacement adjustment of the laser mounting plate 201 in the three-dimensional direction of space can be achieved, thereby adjusting the irradiation position and angle of the laser, so that the laser can accurately irradiate the designated area of ​​the plastic bottle blank, more accurately adjust the irradiation position of the laser, ensure that the laser energy can be efficiently transmitted to various parts of the bottle blank, achieve a uniform and accurate heating effect, and improve the heating quality and production efficiency.

[0039] Specifically, two first adjustment shafts 204 are arranged in parallel, and two second adjustment shafts 205 are also arranged in parallel. The bottoms of the two second adjustment shafts 205 are fixedly connected with first adjustment blocks, and the first adjustment blocks are slidably mounted on the two first adjustment shafts 204. A second adjustment block is installed at the rear end of the third adjustment shaft 206, and the second adjustment block is slidably mounted on the two second adjustment shafts 205. In order to lock the second adjustment block on the second adjustment shaft 205, a locking member is also arranged on the second adjustment shaft 205. In this embodiment, a limited locking nut is installed on the second adjustment shaft 205, and the locking nut is threadedly matched with the second adjustment shaft 205, and the locking nut is arranged at the bottom of the second adjustment block, and the position of the second adjustment block on the second adjustment shaft 205 is limited by abutting the second adjustment block.

[0040] In one embodiment, the conveying assembly 1 further includes a supporting track 102, on which a conveying chain 103 is slidably mounted, and the mounting turntable 101 is rotatably mounted on the conveying chain 103; a conveying driving member 104 is in transmission cooperation with the conveying chain 103 to drive the conveying chain 103 to carry the mounting turntable 101 to move along the supporting track 102. The conveying driving member 104 is in transmission cooperation with the conveying chain 103 to drive the conveying chain 103 to move along the supporting track 102, thereby driving the mounting turntable 101 and the plastic preform mounted on the supporting track 102 to move in a predetermined direction, and sequentially transporting the preform to the heating station and the next production link. The supporting track 102 provides support for the conveying chain 103, ensures the stability of the conveying chain 103 during movement, and prevents the preform from shaking or deflecting during transportation.

[0041] In some other embodiments, the conveying assembly 1 may also use other forms of conveying mechanisms. For example, a belt conveyor may be used, and the rotating disc 101 and the preforms may be driven to be conveyed by the circular motion of the belt, and a plurality of supporting rollers may be arranged under the belt to further improve the stability of the conveying process. Alternatively, a magnetic suspension conveying device may be used.

[0042] In one embodiment, the rotary drive assembly 3 includes a drive chain 302, and a matching gear 301 is provided on the mounting turntable 101, and the drive chain 302 is adapted to mesh with the matching gear 301. When the drive chain 302 moves under the drive of the power source, the mounting turntable 101 and the plastic bottle blank thereon are driven to rotate through meshing transmission with the matching gear 301, so that the bottle blank can be heated evenly during the heating process, ensuring the uniformity and consistency of the heating of the bottle blank, effectively improving the quality and performance of the molded bottle, and meeting the strict requirements for the uniformity of heating the bottle blank during the production process. The meshing transmission mode of the drive chain 302 and the matching gear 301 has high transmission accuracy and torque transmission capacity, which can ensure that the mounting turntable 101 rotates at a stable speed, so that the plastic bottle blank can be uniformly irradiated by the laser during the heating process, avoiding the problem of uneven heating of the bottle blank caused by unstable speed, and further improving the stability and reliability of the heating process.

[0043] In some other embodiments, the rotation drive assembly 3 may also use other forms of drive mechanisms. For example, a servo motor may be used to directly drive the installation turntable 101 to rotate, and by accurately controlling the speed and rotation angle of the servo motor, high-precision control of the bottle blank rotation process is achieved to meet the requirements of a higher-precision heating process. Alternatively, a pneumatic motor may be used as a power source, and the output torque and speed of the pneumatic motor may be adjusted through a pneumatic control system to drive the installation turntable 101 to rotate.

[0044] In one embodiment, the rotary drive assembly 3 further includes two driving toothed discs 303, one of which is equipped with a driving motor as a rotary drive member, and a driving chain 302 is circulated and installed on the plurality of driving toothed discs 303, and the driving toothed discs 303 are meshed with the driving chain 302. The rotary drive member drives one of the driving toothed discs 303 to rotate, thereby driving the driving chain 302 to circulate, and the driving chain 302 is meshed with the matching gear 301 on the mounting turntable 101 to drive the mounting turntable 101 to rotate. The rotation speed of the mounting turntable 101 can be adjusted according to the rotation speed of the driving toothed disc 303 driven by the rotary drive member to rotate, so as to adapt to different production speeds and bottle blank rotation requirements, further improve the stability and uniformity of the bottle blank rotation during the heating process, and ensure the heating quality. In practical applications, the number and position of the driving toothed discs 303 and the rotary drive member can be adjusted according to actual conditions.

[0045] In one embodiment, the light beam emitted by the laser array assembly 2 is designed to be square-conical. When this square-conical light beam is irradiated on the plastic bottle blank, a light spot of a specific shape and size can be formed on the surface of the bottle blank, thereby achieving a uniform heating effect on the bottle blank. The square-conical light beam has the advantages of better energy distribution uniformity and controllability of the light spot shape. Compared with the traditional circular light spot, the square-conical light spot can better match the shape and size characteristics of the plastic bottle blank, making the laser energy more evenly distributed on the surface of the bottle blank, effectively avoiding the problem of uneven heating caused by excessive or low local energy, and significantly improving the heating quality.

[0046] At the same time, the edge of the square cone-shaped light beam is relatively clear, which is conducive to the precise heating of the edge area of ​​the bottle blank, further improving the appearance quality of the molded bottle, and meeting the market's appearance requirements for high-quality plastic bottles. In some other embodiments, the shape of the light beam of the laser array assembly 2 can also be adjusted according to actual production needs. For example, an elliptical beam can be used, and by reasonably adjusting the length of the major axis and minor axis of the elliptical beam, it can better adapt to the shape characteristics of the bottle blank and achieve a more uniform heating effect. Alternatively, an annular beam can be used, and the characteristics of the central dark area and the surrounding bright area of ​​the annular beam can be used to perform special heating treatment on the bottle blank to meet some special process requirements, further expanding the application scope of the device under different production processes.

[0047] In one embodiment, the plastic preform laser heating device further comprises a feeding mechanism 4, which is mounted at an upstream position of the laser array assembly 2. The feeding mechanism 4 is mainly composed of a flip driving motor as a flip driving member 401 and a feeding gripper 402, wherein the feeding gripper 402 is mounted at the driving end of the flip driving member 401. During the feeding process, the flip driving member 401 drives the feeding gripper 402 to perform a flipping action, and after accurately grabbing the plastic preform from the feeding position, the plastic preform 5 is placed upside down on the mounting turntable 101 on the conveying assembly 1 through a flipping operation, thereby completing the feeding operation of the preform. The whole process is efficient and stable, and provides good material preparation for the subsequent heating process. In this embodiment, the mounting turntable 101 is an upwardly protruding annular structure, so it is suitable for mounting the bottle mouth of the plastic preform 5 upside down on the mounting turntable 101, so that the plastic preform 5 can be directly conveyed to the downstream and enter the blow molding machine suitable for inverted blow molding to perform the next blow molding operation. In some other embodiments, the mounting turntable 101 may also be a concave network frame structure, and the plastic bottle blanks 5 may be directly placed upright or inverted into the concave frame. Setting the mounting turntable 101 as a frame structure can minimize the obstruction of the plastic bottle blanks 5 by the mounting turntable 101, so that the laser beam can irradiate the area of ​​the plastic bottle blanks 5 built into the mounting turntable 101, so that the plastic bottle blanks 5 can be directly conveyed downstream to enter a bottle blowing machine suitable for upright bottle blowing for the next blow molding operation.

[0048] By installing the feeding mechanism 4, the degree of automation of the feeding process can be effectively improved, the manual operation links can be reduced, the labor intensity can be reduced, and the production efficiency can be improved. At the same time, the position accuracy of the preforms in the feeding process can be ensured, which provides a strong guarantee for the subsequent heating and molding processes. In some other embodiments, the feeding mechanism 4 can also adopt other forms of structures and working methods. For example, a vibration plate feeding device can be used to automatically arrange the preforms and transport them to the feeding position through the vibration plate, and then the robot grabs them and places them on the installation turntable 101.

[0049] According to an embodiment of the present invention, on the other hand, a plastic bottle molding production line is also provided, which has a plastic bottle preform laser heating device of the present invention, and a blow molding device is also arranged downstream of the plastic bottle preform laser heating device. The plastic bottle preform laser heating device is used to perform efficient and uniform heating treatment on the plastic bottle preform 5 to ensure that the bottle preform can achieve an ideal molding effect in the subsequent blow molding process. The heated plastic bottle preform 5 is sequentially transported to the blow molding device through the conveying component 1 to complete the final product molding. When the plastic bottle molding production line is running, the plastic bottle preform 5 is first placed on the mounting turntable 101 of the laser heating device through the feeding mechanism 4, and after being uniformly heated by the laser heating device, it is transported to the blow molding device through the conveying component 1. In the blow molding device, the heated bottle preform is blown and formed by the blowing system, and is quickly cooled and formed by the cooling system. The molded plastic bottle is inspected by the quality inspection device, and qualified products enter the finished product collection link, and unqualified products enter the waste recycling link, thereby realizing efficient and automatic operation of the entire production process.

[0050] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A laser heating device for plastic preforms, characterized in that: include: A conveying assembly (1) having a mounting turntable (101) mounted thereon, and the plastic bottle blank (5) is suitable for being mounted on the mounting turntable (101); A laser array assembly (2) emits a laser beam that completely irradiates at least the height direction of the plastic bottle blank (5), and the wavelength of the laser beam is 1700nm to 1880nm; A rotary drive assembly (3) is installed corresponding to the laser array assembly (2), and the rotary drive assembly (3) cooperates with the mounting turntable (101) so that the mounting turntable (101) rotates with the plastic bottle blank (5) when passing through the area of ​​the laser array assembly (2).

2. The laser heating device for plastic preforms according to claim 1 is characterized in that: The wavelength of the laser beam is 1710 nm.

3. The laser heating device for plastic preforms according to claim 1 or 2, characterized in that: The laser array assembly (2) comprises a laser mounting plate (201) and a laser group (202) mounted on the laser mounting plate (201); a plurality of laser groups (202) are arranged at intervals along the transmission direction of the transmission assembly (1); each laser group (202) comprises at least one laser body (2021) arranged at intervals along the height direction of the laser mounting plate (201).

4. The laser heating device for plastic preforms according to claim 3 is characterized in that: The laser array assembly (2) further comprises: A mounting platform (203) is fixedly mounted with a first adjustment shaft (204), a second adjustment shaft (205) is slidably mounted on the first adjustment shaft (204), a third adjustment shaft (206) is slidably mounted on the second adjustment shaft (205), the first adjustment shaft (204), the second adjustment shaft (205) and the third adjustment shaft (206) are arranged perpendicular to each other in pairs, and the laser mounting plate (201) is fixedly mounted on the third adjustment shaft (206).

5. The laser heating device for plastic preforms according to claim 1 or 2, characterized in that: The transmission component (1) further comprises: A supporting rail (102) on which a conveying chain (103) is slidably mounted, and the mounting turntable (101) is rotatably mounted on the conveying chain (103); The transmission driving member (104) cooperates with the transmission chain (103) to drive the transmission chain (103) to carry the installation turntable (101) to move along the supporting track (102).

6. The laser heating device for plastic preforms according to claim 1 or 2, characterized in that: The rotary drive assembly (3) comprises a drive chain (302), a matching gear (301) is provided on the mounting turntable (101), and the drive chain (302) is suitable for meshing with the matching gear (301).

7. The laser heating device for plastic preforms according to claim 6, characterized in that: The rotary drive assembly (3) further comprises at least two drive sprockets (303), at least one of the drive sprockets (303) being provided with a rotary drive member, the drive chain (302) being cyclically mounted on a plurality of the drive sprockets (303), and the drive sprockets (303) being meshed with the drive chain (302).

8. The laser heating device for plastic preforms according to claim 1 or 2, characterized in that: The light beam emitted by the laser array component (2) is in a square cone shape.

9. The laser heating device for plastic preforms according to claim 1 or 2, characterized in that: It also includes a loading mechanism (4) installed upstream of the laser array assembly (2), the loading mechanism (4) including a flip driving member (401) and a loading gripper (402), the loading gripper (402) being installed at the driving end of the flip driving member (401), and the flip driving member (401) being suitable for driving the loading gripper (402) to flip and load.

10. A plastic bottle forming production line, characterized in that: A plastic bottle preform laser heating device according to any one of claims 1 to 9, wherein a blow molding device is further arranged downstream of the plastic bottle preform laser heating device.

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