High speed stretch forming apparatus for wrapping film
Patent Information
- Application Number
- CN202522468945.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-21
- Publication Date
- 2026-10-30
- Estimated Expiration
- 2035-11-21
AI Technical Summary
[0003]但现有技术中，张力控制是缠绕膜拉伸成型过程的核心，直接影响薄膜的分子取向、厚度均匀性及力学性能，现有设备的张力控制多采用“单端检测+被动调节”模式，仅在拉伸辊组的进料端或出料端设置单一张力传感器，无法实时捕捉拉伸过程中薄膜张力的动态变化，由于高速拉伸状态下，薄膜与辊体之间的摩擦系数波动、原料塑化不均导致的熔体粘度差异，以及环境温度、湿度变化等因素，均会引发张力波动，而单一检测点的信号滞后性，使得调节机构无法及时响应，导致薄膜出现局部褶皱、厚薄偏差，甚至出现断裂现象，严重影响产品质量
[0011]与现有技术相比，本实用新型的优点和积极效果在于：
Smart Images
Figure CN224915345U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of stretch film production equipment, and in particular to a high-speed stretch forming equipment for stretch film. Background Technology
[0002] Stretch film, also known as cling film, has become a core packaging material for cargo consolidation, securing, moisture protection, and dust prevention in logistics, warehousing, food processing, and electronics manufacturing due to its excellent self-adhesion, tensile strength, and puncture resistance. With the rapid development of global supply chains and the explosive growth of e-commerce, market demand for stretch film continues to rise, with high-strength, ultra-thin stretch film particularly favored for its compliance with green packaging and cost control requirements. This market demand directly drives the upgrading of stretch film production equipment towards "high speed, high precision, and high efficiency." High-speed stretch forming, as a core process in stretch film production, directly determines the physical properties, production efficiency, and production costs of the product, making it a key focus of technological competition within the industry.
[0003] However, in existing technologies, tension control is the core of the stretching and forming process of the wrapping film, directly affecting the molecular orientation, thickness uniformity, and mechanical properties of the film. The tension control of existing equipment mostly adopts the "single-end detection + passive adjustment" mode, which only sets a single tension sensor at the feeding end or the discharge end of the stretching roller group. It cannot capture the dynamic changes of film tension in real time during the stretching process. Due to the fluctuation of the friction coefficient between the film and the roller, the difference in melt viscosity caused by uneven plasticization of raw materials, and the changes in ambient temperature and humidity, tension fluctuations can be caused by factors such as high-speed stretching. The signal lag of a single detection point makes it impossible for the adjustment mechanism to respond in time, resulting in local wrinkles, thickness deviations, and even breakage of the film, which seriously affects product quality. Utility Model Content
[0004] The purpose of this invention is to solve the problems existing in the prior art by proposing a high-speed stretching and forming equipment for wrapping film.
[0005] To achieve the above objectives, the present invention adopts the following technical solution: a high-speed stretching and forming equipment for stretch film, including a stretching device, a controller installed at the upper end of the stretching device, a tension detection mechanism provided at one end of the frame of the stretching device, and a tension adjustment mechanism provided at one end of the frame of the stretching device for adjusting the tension of the stretch film; The tension detection mechanism includes two sets of fixed plates, with a rotating rod rotatably mounted between the two sets of fixed plates. Tension sensors are installed on the outer wall of the rotating rod near both ends, and guide rollers are installed on the outer wall of the rotating rod.
[0006] Preferably, one side of each of the two sets of fixing plates is fixed to the inner walls of both sides of the tension device frame, and the two sets of tension sensors are connected to the controller signal.
[0007] Preferably, the tension adjustment mechanism includes two sets of fixed seats, each set of fixed seats having a cylinder rotatably mounted at one end. A concave seat is rotatably mounted inside the tensioning device frame, and two sets of connectors are rotatably mounted at one end of the concave seat. A long rod is rotatably mounted in the middle of the concave seat, and a tension roller is fixedly mounted on the outer wall of the long rod.
[0008] Preferably, one end of each of the two sets of fixed seats is fixed to one end of the crossbeam inside the tensioning device frame, and the extended ends of each of the two sets of cylinders are respectively fixed to one end of each of the two sets of connectors.
[0009] Preferably, both sets of cylinders are connected to the controller signal.
[0010] Preferably, auxiliary guide components are installed on the outer wall of the long rod and near the edges at both ends.
[0011] Compared with the prior art, the advantages and positive effects of this utility model are as follows: 1. In this utility model, the tension detection accuracy is high: the dual tension sensors are symmetrically arranged and combined with the design of a large-diameter guide roller, which improves the stability and accuracy of tension detection and solves the problem of insufficient detection accuracy of traditional single sensors.
[0012] 2. In this utility model, the adjustment response speed is fast: the lever-type adjustment structure driven by servo cylinder is used in conjunction with a high-precision controller, which can effectively suppress tension fluctuations during high-speed stretching. Through precise tension control, the uniformity of film stretching is significantly improved, and quality problems such as film wrinkles and tears are effectively reduced. Attached Figure Description
[0013] Figure 1 This utility model provides a three-dimensional structural schematic diagram of a high-speed stretching and forming equipment for wrapping film; Figure 2 A top view of a high-speed stretch forming equipment for wrapping film is provided for this utility model; Figure 3 This utility model provides a perspective view of a tension detection mechanism and a tension adjustment mechanism for a high-speed stretching and forming equipment for wrapping film; Figure 4 This utility model presents a perspective view of a tension detection mechanism for a high-speed stretching and forming equipment for wrapping film.
[0014] Legend: 1. Tensioning device; 11. Controller; 2. Tension detection mechanism; 21. Fixing plate; 22. Rotating rod; 23. Tension sensor; 24. Guide roller; 3. Tension adjustment mechanism; 31. Fixing seat; 32. Cylinder; 33. Concave seat; 34. Connector; 35. Long rod; 36. Tension roller; 37. Auxiliary guide assembly. Detailed Implementation
[0015] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.
[0016] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.
[0017] Example 1: As Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, this utility model provides a high-speed stretching and forming equipment for stretch film, including a stretching device 1, a controller 11 installed at the upper end of the stretching device 1, a tension detection mechanism 2 provided at one end of the frame of the stretching device 1, and a tension adjustment mechanism 3 provided at one end of the frame of the stretching device 1 for adjusting the tension of the stretch film. The tension detection mechanism 2 includes two sets of fixed plates 21. A rotating rod 22 is rotatably mounted in the middle of the two sets of fixed plates 21. Tension sensors 23 are installed on the outer wall of the rotating rod 22 near the edges of both ends. Guide rollers 24 are installed on the outer wall of the rotating rod 22. One side of the two sets of fixed plates 21 is fixed to the inner walls of the two sides of the frame of the tensioning device 1, respectively. Both sets of tension sensors 23 are connected to the controller 11.
[0018] The specific settings and functions of this embodiment are described below. The stretching device 1 is the core functional unit of the high-speed stretching and forming equipment for stretch film. It is mainly responsible for the directional stretching of the extruded film and improving its mechanical properties by adjusting the molecular arrangement structure of the film. The device adopts a high-strength alloy steel frame, which has good structural stability and vibration resistance. The upper end face of the tensioning device 1 is fixedly mounted with a controller 11 by a shockproof bracket. The controller 11 adopts a Siemens S7-1200 series PLC and is equipped with a 7-inch touch screen. It can display the equipment operating parameters in real time and support manual parameter adjustment. The controller 11 integrates a tension closed-loop control algorithm, which can adjust the actuator in real time according to the detection data. A tension detection mechanism 2 is provided at the feed end of the frame of the stretching device 1 to monitor the tension state of the film entering the stretching area in real time; a tension adjustment mechanism 3 is provided in the middle of the frame to ensure that the stretching process is stable and controllable by dynamically adjusting the film tension. The two mechanisms and the controller 11 form a complete tension control system to realize fully automatic closed-loop control from detection to adjustment. The tension testing mechanism 2 adopts a double fixed plate 21 support structure, specifically including: two sets of symmetrically arranged fixed plates 21, which are made of 45# steel plate after heat treatment, and are rigidly connected to the inner walls of both sides of the tension device 1 frame by high-strength bolts. The contact surface between the fixed plate 21 and the frame is equipped with shock-absorbing pads, which can reduce the impact of equipment vibration on the testing accuracy. A rotating rod 22 is rotatably mounted in the middle of the two sets of fixed plates 21 via a precision bearing. The rotating rod 22 is made of 304 stainless steel to ensure smooth rotation without jamming. Two tension sensors 23 are symmetrically installed at both ends of the outer wall of the rotating rod 22. These are high-precision strain gauge sensors that can capture instantaneous tension fluctuations during high-speed stretching. A guide roller 24 is fixedly installed in the middle of the outer wall of the rotating rod 22. The roller body is made of aluminum alloy with a Teflon coating. Its length is adapted to the width of the film. The guide roller 24 has baffles at both ends to prevent the film from deviating. The tension sensor 23 is connected to the controller 11 via a shielded cable. The cable is protected by a conduit to avoid electromagnetic interference affecting the detection signal. During operation, the film passes over the guide roller 24 (with an encirclement angle of approximately 120°), causing the rotating rod 22 to rotate synchronously with the film. The film tension is transmitted to the rotating rod 22 through the guide roller 24, causing the tension sensor 23 to undergo a slight deformation. The sensor converts the mechanical signal into a standard electrical signal and transmits it to the controller 11, thereby achieving real-time tension monitoring.
[0019] Example 2: Figure 1 , Figure 2 and Figure 3 As shown, the tension adjustment mechanism 3 includes two sets of fixed seats 31. A cylinder 32 is rotatably mounted on one end of each of the two sets of fixed seats 31. A concave seat 33 is rotatably mounted inside the frame of the tensioning device 1. Two sets of connectors 34 are rotatably mounted on one end of the concave seat 33. A long rod 35 is rotatably mounted in the middle of the concave seat 33. A tension roller 36 is fixedly mounted on the outer wall of the long rod 35. One end of each of the two sets of fixed seats 31 is fixed to one end of the crossbeam inside the frame of the tensioning device 1. The extended ends of the two sets of cylinders 32 are respectively fixed to one end of each of the two sets of connectors 34. Both sets of cylinders 32 are signal connected to the controller 11. An auxiliary guide assembly 37 is installed on the outer wall of the long rod 35 near both ends.
[0020] The overall effect of the embodiment is that the tension adjustment mechanism 3 adopts a lever-type adjustment structure driven by a dual cylinder, specifically including: two sets of fixed seats 31, which are integrally formed of cast steel and rigidly connected to one end of the crossbeam inside the frame of the tension device 1 through a flange. The bottom of the fixed seat 31 is provided with reinforcing ribs to improve the load-bearing capacity. One end of each of the two sets of fixed seats 31 is rotatably mounted with a cylinder 32 via a spherical bearing. The cylinder is an SMC series servo cylinder. Inside the frame of the tensioning device 1, a concave seat 33 is rotatably mounted via a rotating shaft. The concave seat is made of aluminum alloy and has an overall U-shaped structure. Bearing seats are provided at both ends to ensure flexible rotation. Two sets of connectors 34 are rotatably mounted on one end of the concave seat 33 via a pin. The connectors 34 are made of high-strength alloy material and are rigidly connected to the protruding end of the cylinder 32 via threads. Anti-loosening nuts are provided at the connection.
[0021] A long rod 35 is rotatably mounted on the middle position of the concave seat 33 via a bearing. A tension roller 36 with chrome plating is fixedly mounted on the outer wall of the long rod 35, and wear-resistant bushings are provided at both ends to effectively reduce film edge wear. An auxiliary guide assembly 37 is installed on the outer wall of the long rod 35 near both ends. This assembly includes a guide wheel and an adjustment bracket, which can accurately guide the film edge and prevent film deviation. Two sets of cylinders 32 are connected to the controller 11 via a solenoid valve group to ensure fast and accurate adjustment. During operation, the controller 11 calculates the tension value to be adjusted based on the signal transmitted from the tension detection mechanism 2. By controlling the extension and retraction of the two sets of cylinders 32, it drives the concave seat 33 to rotate around the axis, thereby changing the position and height of the tension roller 36 and adjusting the contact wrap angle between the film and the tension roller 36 (adjustment range 30°-150°), thus realizing the dynamic adjustment of film tension.
[0022] The usage and working principle of this device are as follows: First, tension detection: When the stretch film passes through the guide roller 24, its tension is transmitted to the tension sensor 23 through the rotating rod 22. The sensor converts the mechanical signal into an electrical signal and transmits it to the controller 11 in real time. Signal processing: Controller 11 compares the preset tension value with the real-time detection value and calculates the adjustment amount; Tension adjustment: The controller 11 commands the two sets of cylinders 32 to extend and retract, driving the concave seat 33 to rotate, changing the position of the tension roller 36 to adjust the film contact wrap angle, and achieving dynamic tension balance; Collaborative operation: The auxiliary guide component 37 ensures that the film does not deviate, and the whole process forms a closed-loop control to ensure stable tension during high-speed stretching.
[0023] The above are merely preferred embodiments of this utility model and are not intended to limit the utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from the technical solution of this utility model shall still fall within the protection scope of this utility model.
Claims
1. A high-speed stretching and forming equipment for stretch film, comprising a stretching device (1), characterized in that: The upper end of the stretching device (1) is equipped with a controller (11), one end of the frame of the stretching device (1) is provided with a tension detection mechanism (2), and one end of the frame of the stretching device (1) is provided with a tension adjustment mechanism (3) for adjusting the tension of the wrapping film. The tension detection mechanism (2) includes two sets of fixed plates (21), and a rotating rod (22) is rotatably installed in the middle of the two sets of fixed plates (21). Tension sensors (23) are installed on the outer wall of the rotating rod (22) and near the edges of both ends. Guide rollers (24) are installed on the outer wall of the rotating rod (22).
2. The high-speed stretching and forming equipment for stretch film according to claim 1, characterized in that: One side of each of the two sets of fixing plates (21) is fixed to the inner walls of both sides of the frame of the tensioning device (1), and both sets of tension sensors (23) are connected to the controller (11) via signal.
3. The high-speed stretching and forming equipment for stretch film according to claim 1, characterized in that: The tension adjustment mechanism (3) includes two sets of fixed seats (31), and a cylinder (32) is rotatably installed at one end of each of the two sets of fixed seats (31). A concave seat (33) is rotatably installed inside the frame of the tensioning device (1). Two sets of connectors (34) are rotatably installed at one end of the concave seat (33). A long rod (35) is rotatably installed in the middle of the concave seat (33). A tension roller (36) is fixedly installed on the outer wall of the long rod (35).
4. The high-speed stretching and forming equipment for stretch film according to claim 3, characterized in that: One end of each of the two sets of fixed seats (31) is fixed to one end of the crossbeam inside the frame of the tensioning device (1), and the extended ends of the two sets of cylinders (32) are respectively fixed to one end of each of the two sets of connectors (34).
5. The high-speed stretching and forming equipment for stretch film according to claim 4, characterized in that: Both sets of cylinders (32) are connected to the controller (11) via signal.
6. The high-speed stretching and forming equipment for stretch film according to claim 5, characterized in that: Auxiliary guide components (37) are installed on the outer wall of the long rod (35) and near the edges of both ends.