Heat shrink film machine

Abstract

The present invention relates to the technical field of packaging equipment, and discloses a heat shrink film machine for heat shrinking packaging films of packaging objects on a conveyor line, comprising a lifting device suspended above the conveyor line, the lifting device being mounted on a bracket, a heat shrink tube being connected to the end of the lifting device, and a steam generator for conveying steam to the heat shrink tube, the heat shrink tube having a double-layer wall, the inner wall having a plurality of injection ports for steam ejection, and a first solenoid valve being provided between the steam generator and the heat shrink tube for controlling the input of steam. The heat shrink film machine of the present application, while following the traditional steam heat shrinking method, ingeniously reduces the steam ejection area to an area adapted to the part of the packaging object that needs to be heat shrunk, so that the packaging film is heated evenly, and the heat shrinking time is strictly controlled, the steam will not adhere to the surface of the heat shrinking part, and the dry state of the packaging object is effectively maintained.

Description

Technical Field

[0001] This invention belongs to the field of packaging equipment technology, specifically, it relates to a heat shrink film machine. Background Technology

[0002] Currently, packaging shrink film on the market uses electric heating tunnel shrinking and steam tunnel shrinking.

[0003] The principle of electric heating tunnel heat shrink is to use electric heating wires to heat the air, and a fan to drive the airflow. The heat exchange produces hot air, which brings the heat shrink temperature inside the tunnel to the point where the heat shrink film locks the packaged item in place when heated.

[0004] The principle of steam tunnel heat shrink is that a steam generator produces steam, which is sprayed out inside the tunnel. When the heat shrink film reaches the heat shrink temperature, it is heated and locks the packaged item in place.

[0005] Electric heating tunnel shrink wrapping causes wrinkles and an unsightly appearance due to uneven hot air temperature. Steam tunnel shrink wrapping requires a longer contact time between steam and the packaged goods to achieve the desired shrinkage effect. However, prolonged steam spraying leads to excessive condensation and dampness on the surface of the packaged goods, the surrounding equipment, and the environment. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned shortcomings of the prior art and provide a heat shrink film machine that allows for uniform heating of the packaging film and controllable steam injection time.

[0007] The technical solution of the present invention is: a heat shrink film machine for heat shrinking the packaging film of packaged goods on a conveyor line, including a lifting device suspended above the conveyor line, the lifting device being mounted on a bracket, the end of the lifting device being connected to a heat shrink cylinder, and also including a steam generator for supplying steam to the heat shrink cylinder, the heat shrink cylinder having a double-layered wall, the inner layer having multiple injection ports for steam to be ejected, and a first valve being provided between the steam generator and the heat shrink cylinder for controlling the input of steam.

[0008] A further technical solution of the present invention is: the lifting device is a cylinder, and also includes an air compressor, with a second valve for controlling the operation of the cylinder provided between the air compressor and the cylinder.

[0009] A further technical solution of the present invention is: it also includes a first sensing probe for sensing the position of the package, the first sensing probe being electrically connected to the second valve.

[0010] A further technical solution of the present invention is: a telescopic device for intercepting packaged goods is provided on either side of the conveyor line, and the telescopic device is electrically connected to the first sensing probe.

[0011] A further technical solution of the present invention is: it also includes a second sensing probe for sensing the position of the heat shrink tubing, the second sensing probe being electrically connected to the first valve.

[0012] A further technical solution of the present invention is that the second valve is a solenoid valve, and a time delay switch is also connected to the second valve.

[0013] A further technical solution of the present invention is: a condensate drain outlet is provided at the bottom of the heat shrink tubing near the packaged item, and a drain pipe is connected to the condensate drain outlet.

[0014] A further technical solution of the present invention is: the support includes vertical supports on both sides of the conveyor chain and a horizontal support between the two vertical supports. The lifting device is installed on the horizontal support. The two ends of the horizontal support have bent portions that fit with the vertical supports. The top of the vertical support has a vertical slot for the horizontal support to move up and down. The bent portions of the horizontal support and the vertical support are connected by fasteners.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] 1) The heat shrink film machine of this application ingeniously reduces the steam injection area to a size that matches the area of ​​the packaged product that needs to be heat-shrinked, while still using the traditional steam heat shrink method. This makes the packaging film heat evenly, and the heat shrinking time is strictly controlled. Steam will not adhere to the surface of the heat-shrinking area, effectively keeping the packaged product dry.

[0017] 2) The operation of the steam generator and the air compressor are controlled by the first valve and the second valve respectively. At the same time, the first sensor probe and the second sensor probe are set to indicate the opening or closing of the second valve and the first valve respectively. This is equivalent to forming an "Internet" for the overall working process of the heat shrink film machine, so that the shrinking process of the packaged goods can be carried out automatically, quickly and efficiently.

[0018] 3) The condensate drain outlet at the bottom of the heat shrink tubing ensures that condensate drains out through the drain pipe, preventing it from dripping onto the packaging.

[0019] 4) The horizontal support on the bracket can change its position on the vertical support, which improves the applicability of the heat shrink film machine of this application. That is, the horizontal support can be adjusted according to the height of the packaged goods without requiring too much from the lifting device.

[0020] The detailed structure of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0021] Figure 1 This is a simplified structural diagram of the heat shrink film machine described in Example 1. Detailed Implementation

[0022] Example 1

[0023] like Figure 1As shown, a heat shrink film machine is provided for heat shrinking the packaging film of packaged goods B on a conveyor line A. It includes a lifting device 1 suspended above the conveyor line A. The position of the lifting device along the length of the conveyor line can be arbitrarily set, as long as it corresponds to the position of the packaged goods conveyed on the central axis of the conveyor line. Specifically, the lifting device 1 can be installed on a bracket 2. The end of the lifting device 1 is connected to a heat shrink cylinder 3. It also includes a steam generator 4 for supplying steam to the heat shrink cylinder 3. The heat shrink cylinder 3 has a double-layered wall. The inner wall has multiple injection ports for steam to be sprayed out. The injection ports are evenly distributed on the inner wall. A first valve is also provided between the steam generator 4 and the heat shrink cylinder 3 to control the supply of steam. The first valve is a solenoid valve, which will be referred to as the first solenoid valve 5 below.

[0024] To improve the lifting accuracy of the lifting device, a cylinder is selected for the lifting device 1. An air compressor 6 is also provided to match the cylinder. A second valve, which is also a solenoid valve, is installed between the air compressor 6 and the cylinder to control the operation of the cylinder. The extension and retraction stroke of the cylinder is precisely controlled and the operation is reliable, ensuring the heat shrinking of the packaging film.

[0025] When the packaged item is conveyed forward by the conveyor line and reaches the corresponding position of the heat shrink tubing, the lifting device needs to descend immediately. To ensure that the lifting device 1 descends in a timely manner, a first sensing probe 81 for sensing the position of the packaged item can be set up. The first sensing probe 81 is electrically connected to the second solenoid valve 7. When the first sensing probe 81 senses that the packaged item has reached the predetermined position, it quickly transmits the information to the second solenoid valve 7. The second solenoid valve 7 then opens to allow gas from the air compressor 6 to enter the cylinder, and the lifting device 1 can descend.

[0026] A spiral bottle divider (not shown) is installed on the conveyor line. When the packaged goods reach the vicinity of the lifting device, the spiral bottle divider separates the packaged goods continuously conveyed on the conveyor line, allowing the heat shrink tube to heat shrink the packaging film of each packaged goods one by one. To prevent the packaged goods from tipping forward or slipping, a telescopic device 9 for intercepting the packaged goods can also be installed on either side of the conveyor line. When the packaged goods reach the predetermined position, the telescopic end of the telescopic device 9 immediately extends. The telescopic device 9 is electrically connected to the first sensing probe 81, which provides a rapid response signal to the telescopic device. The telescopic device is also a cylinder. The air compressor and the second solenoid valve mentioned above are also connected to this telescopic device, meaning that the telescopic device here and the lifting device mentioned above work synchronously.

[0027] To enable the first solenoid valve to open and deliver steam immediately after the heat shrink tubing descends to the designated position, a second sensing probe 82 can be installed to sense the position of the heat shrink tubing 3. The second sensing probe 82 is electrically connected to the first solenoid valve 5. Generally, the second sensing probe is used to detect whether the bottom of the heat shrink tubing has reached the designated position.

[0028] The second solenoid valve 7 is also connected to a time delay switch (or it can be implemented by programming control without a time delay switch). The time for the second solenoid valve to close is set. When the second solenoid valve 7 closes, the lifting device 1 and the telescopic device 9 return to their original positions, and the packaged goods continue to be conveyed forward. The heat shrink tube 3 is driven back to its original position by the lifting device 1. When the second sensing probe 82 senses that the heat shrink tube 3 has started to return to its original position, the first solenoid valve 5, which is electrically connected to it, begins to close, and no longer supplies steam to the heat shrink tube. The steam injection operation in the heat shrink tube stops.

[0029] After the heat shrink tubing 3 stops spraying steam, the residual steam on its wall will condense upon cooling. To prevent the condensate from dripping onto the next package, a condensate drain outlet needs to be opened at the bottom of the heat shrink tubing (near the package end). A drain pipe 31 is connected to the condensate drain outlet to drain the condensate.

[0030] To further enhance the applicability of the heat shrink film machine in this embodiment to packaging materials of different heights, the support 2 can be specially designed. Specifically, the support 2 includes vertical supports 21 located on both sides of the conveyor chain and a horizontal support 22 erected between the two vertical supports. The lifting device 1 is installed on the horizontal support 22. The horizontal support has bent portions 221 at both ends that fit against the vertical supports. The vertical support 21 has a vertical slot (not shown) starting from the top for the horizontal support 22 to move up and down. The bent portions 221 of the horizontal support and the vertical support 21 are fastened together by fasteners 23, which are bolts and nuts. When the packaging material is tall, the horizontal support is also installed tall. When the packaging material is short, the bolts and nuts between the horizontal support and the vertical support are loosened, allowing the horizontal support to move down a distance along the vertical slot until the heat shrink cylinder can cover the packaging film to be heat-shrinked. Then the bolts and nuts are tightened, thus fixing the position of the horizontal support.

[0031] In this embodiment, the first sensing probe and the second sensing probe are common infrared sensors available on the market.

[0032] This invention is not limited to the specific structure or connection method described above. Any heat shrink film machine structure that has the same or similar concept as this technical solution falls within the protection scope of this invention.

Claims

1. A heat shrink film machine, characterized in that: Used for heat shrinking the packaging film of the packaging (B) on the conveyor line (A), comprising a lifting device (1) suspended above the conveyor line, the lifting device being mounted on a bracket (2), the end of the lifting device (1) being connected to a heat shrink tube (3), and also comprising a steam generator (4) for conveying steam to the heat shrink tube, the heat shrink tube having a double-layer wall, the inner wall of which having a plurality of injection ports for steam ejection, and a first valve (5) being provided between the steam generator (4) and the heat shrink tube (3) for controlling the input of steam; the steam injection area of ​​the injection port is an area adapted to the part of the packaging to be heat shrunk, so that the packaging film is heated evenly; the heat shrink tube (3) is provided with a condensation water outlet near the bottom of the packaging; The lifting device (1) is a cylinder and also includes an air compressor (6). A second valve (7) for controlling the operation of the cylinder is provided between the air compressor and the cylinder. It also includes a first sensing probe (81) for sensing the position of the packaged object, the first sensing probe (81) being electrically connected to the second valve (7); It also includes a second sensing probe (82) for sensing the position of the heat shrink tube (3), and the second sensing probe (82) is electrically connected to the first valve (5); The first sensing probe (81) senses that the packaged object has reached a predetermined position, the second valve (7) opens to cause the lifting device (1) to descend, and after the second sensing probe (82) senses that the heat shrink tube (3) has descended into position, the first valve (5) immediately opens to deliver steam; after the second valve (7) closes, the lifting device (1) returns to its original position, driving the heat shrink tube (3) to return to its original position, and the second sensing probe (82) senses that the heat shrink tube (3) has begun to return to its original position, the first valve (5) begins to close, and the steam injection operation in the heat shrink tube (3) stops.

2. The heat shrink film machine according to claim 1, characterized in that: A telescopic device (9) for intercepting packaging objects is also provided on either side of the conveyor line, and the telescopic device (9) is electrically connected to the first sensing probe (81).

3. The heat shrink film machine according to claim 1, characterized in that: The second valve is a solenoid valve, and a time delay switch is also connected to the second valve (7).

4. The heat shrink film machine according to claim 1, characterized in that: The condensate outlet is connected to a drain pipe (31).

5. The heat shrink film machine according to claim 1, characterized in that: The support (2) comprises a vertical support (21) arranged on both sides of the conveyor chain and a transverse support (22) arranged between the two vertical supports. The lifting device (1) is installed on the transverse support (22). Both ends of the transverse support have a bending portion (221) that fits with the vertical support. The top end of the vertical support has a vertical slot for the transverse support to be moved up and down. The bending portion (221) of the transverse support is connected to the vertical support (21) via a fastener (23).

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