Cooling device for plastic film blow molding

Abstract

The utility model relates to the field of plastic film production, and particularly discloses a cooling device for plastic film blow molding, which is arranged on a film outlet air ring where a plastic film blowing machine is located so as to cool a discharged plastic film. Comprises: a nozzle having an injection path for guiding airflow to be injected in a first direction; the air pipe is connected with the nozzle and the fan; the cooling piece is located between the air pipe and the spray head to reduce the temperature of airflow in the air pipe; a cavity communicating with the nozzles is formed in the air ring, and the nozzles are annularly arrayed in the circumferential direction of the air ring. A connecting piece is arranged between the air pipe and the cavity to communicate the air pipe with the internal space of the cavity; the cooling piece is fixedly arranged in the cavity and located between the connecting piece and the spray head. The cooling piece is filled with a coolant. The cooling device has the beneficial effect that the cooling effect can be improved in plastic film blow molding.

Description

Technical Field

[0001] The present application relates to the field of plastic film production, and in particular to a cooling device for plastic film blow molding. Background Art

[0002] Plastic film can be produced using the upward blowing method. During the production process, the plastic melt is extruded upward from the circular bubble extrusion port of the die head to form a bubble. The bubble is pulled upward continuously, while the cooling air ring located next to the bubble continuously blows air upward. The air not only supports and stabilizes the bubble, but more importantly, it cools the bubble. The cooling device of the film blowing machine generally uses a blower to blow cold air into the cold air ring of the film blowing machine die head to cool the bubble externally during film forming. The cooling temperature directly affects the crystallization process, physical properties, optical properties and production efficiency of the film.

[0003] However, the cooling devices currently designed on the market are all water-cooled. However, in the summer, the workshop temperature is high, which causes the water temperature to rise; this will reduce the cooling effect; therefore, it is necessary to design a cooling device for plastic film blow molding that can improve the cooling effect. Utility Model Content

[0004] In order to improve the above-mentioned problem of low cooling efficiency, the present application provides a cooling device for plastic film blow molding.

[0005] The present application provides a device provided on a film discharge air ring of a plastic film blowing machine to cool the discharged plastic film; the device includes:

[0006] a nozzle having a spray path for guiding an air flow to spray in a first direction;

[0007] Air duct, connecting the nozzle and the fan;

[0008] Cooling element, located between the air duct and the nozzle to reduce the air flow temperature in the air duct;

[0009] Among them, a cavity connected to the nozzle is formed in the air ring, and the nozzles are arranged in a circular array along the circumference of the air ring; a connecting piece is provided between the air duct and the cavity to connect the air duct and the internal space of the cavity; the cooling piece is fixedly arranged in the cavity, located between the connecting piece and the nozzle; the cooling piece is filled with coolant.

[0010] After the fan of this application is started, cooling air will be blown to the nozzle; the cooling air can be effectively cooled by the cooling component setting; in this way, the cooling air can often be lower than room temperature; it can be understood that this application optimizes the cooling system during film blowing to reduce crystallization defects, improve transparency, mechanical properties and thickness uniformity, and at the same time improve production efficiency.

[0011] Optionally, the cooling member is a metal ring formed of a metal structure;

[0012] The metal ring extends along the extension direction of the cavity;

[0013] Dragon scale patterns formed on the surface of the metal ring;

[0014] Among them, the dragon scale pattern completely covers the surface of the metal ring.

[0015] Optionally, the cooling member forms a cooling cavity for the coolant to circulate;

[0016] The cooling chamber is communicated with a liquid storage member storing coolant through a hose;

[0017] Wherein, a solenoid valve is provided on the liquid storage component to control the flow / blockage of the hose.

[0018] Optionally, the connecting piece has an air guide channel connecting the ventilation pipe and the interior space of the cavity;

[0019] The air guide channel forms a flow guide path;

[0020] The extension direction of the guide path intersects with the surface of the metal ring to form a cooling angle;

[0021] Among them, the cooling angle is not greater than 30°.

[0022] Optionally, an air temperature sensor is also provided in the cavity to monitor the air flow temperature;

[0023] The temperature sensor is electrically connected to the central control system of the film blowing machine;

[0024] The central control system is electrically connected to the cooling element to control the start / stop of cooling.

[0025] Optionally, the jet path forms a jet angle of 80°-90° with the surface of the wind ring.

[0026] Optionally, a Tesla valve is provided at the junction between the nozzle and the internal space of the cavity.

[0027] Optionally, a plurality of connecting members are provided and are evenly arranged along the circumferential direction of the air ring.

[0028] Optionally, a flow diverter is provided between the air duct and the fan.

[0029] To sum up, the present application can effectively cool the cooling air through the setting of cooling parts; in this way, the cooling air can often be lower than room temperature; it can be understood that the present application optimizes the cooling system during film blowing to reduce crystallization defects, improve transparency, mechanical properties and thickness uniformity, and at the same time improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1It is a schematic diagram of the overall structure of an embodiment of the present application;

[0031] Figure 2 is a partial cross-sectional view of a cooling device according to an embodiment of the present application;

[0032] Figure 3 is a schematic diagram of a cooling element according to an embodiment of the present application;

[0033] Figure 4 Schematic diagram of the injection angle of an embodiment of the present application;

[0034] Figure 5 It is a schematic diagram of the cooling angle of an embodiment of the present application.

[0035] Figure numerals: 1, cooling device; 2, air ring; 3, nozzle; 4, air duct; 5, cooling part; M, first direction; H, injection path; α, injection angle; β, cooling angle; 6, cavity; 7, connecting part; 8, diverter; 9, dragon scale pattern; 11, hose; 12, air guide channel; 13, Tesla valve; L, guide path. DETAILED DESCRIPTION

[0036] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as being limited to the embodiments described herein. On the contrary, these embodiments are provided to provide a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are for illustrative purposes only and are not intended to limit the scope of protection of the present disclosure.

[0037] It should also be noted that, for ease of description, only the parts related to the relevant utility model are shown in the drawings. In the absence of conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other.

[0038] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0039] It should be noted that the modifications of "one" and "multiple" mentioned in the present disclosure are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, they should be understood as "one or more".

[0040] The present disclosure will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0041] The embodiment of the present application discloses a cooling device 1 for plastic film blow molding, which is arranged on the film discharge air ring 2 where the plastic film blowing machine is located to cool the plastic film being discharged; it includes: a nozzle 3, an air duct 4, and a cooling part 5; specifically, the nozzles 3 are arranged in a ring array along the circumferential direction of the air ring 2, and any nozzle 3 has a spray path H for guiding the air flow to be sprayed along a first direction M, and the spray path H forms a spray angle α of 80°-90° with the surface of the air ring 2; wherein, the spray angle α is preferably 80°, so that when the nozzle 3 sprays out the cooling air flow, it can form an inclination angle with the plastic film. It can be understood that the cooling air flow sprayed by the nozzle 3 forms a spiral airflow distribution on the surface of the plastic film, thereby increasing the contact time and range of the air flow with the plastic film, and effectively improving the cooling effect.

[0042] Specifically, a cavity 6 is formed in the air ring 2, and the cavity 6 extends around the circumference of the air ring 2. A connector 7 is fixed to the side wall of the air ring 2. The fixing method is not limited to bolt connection, welding, or other connection methods that can integrate the connector 7 with the air ring 2. This embodiment does not improve the fixing method of the connector 7, so it will not be described in detail. More specifically, the air duct 4 connects the connector 7 with the fan, so that the airflow produced by the fan can be diverted into the cavity 6 and ejected from the nozzle 3. Preferably, the connectors 7 are arranged in a ring array along the circumference of the air ring 2, and a diverter 8 is provided between the air duct 4 and the fan. The provision of the diverter 8 can evenly distribute the airflow to each air duct 4.

[0043] More specifically, the cooling member 5 is filled with coolant and is arranged in the cavity 6 relative to the connecting member 7 to cool the airflow ejected from the connecting member 7, and the nozzle 3 is located between the connecting member 7 and the cooling member 5, preferably above the cooling member 5; wherein, the cooling member 5 is a metal ring formed by a metal silver or copper structure, and the metal ring extends a circle along the extension direction of the cavity 6; the metal silver or copper with high thermal conductivity can transfer heat from the temperature of the coolant to the airflow ejected from the connecting member 7, thereby improving the cooling efficiency.

[0044] More specifically, dragon scale patterns 9 are formed on the surface of the metal ring, and the dragon scale patterns 9 completely cover the surface of the metal ring; this structural setting can improve the efficiency of heat transfer, especially when the airflow ejected from the connecting part 7 contacts the surface of the metal ring, the temperature of the cooling part 5 can be quickly transferred to the airflow through the dragon scale patterns 9.

[0045] More specifically, the cooling element 5 forms a cooling cavity for the circulation of coolant, and the cooling cavity is connected to the liquid storage element for storing the coolant through the hose 11; wherein, the liquid storage element is provided with a solenoid valve to control the circulation / blockage of the hose 11; in this embodiment, any one of liquid nitrogen and Freon is used as the cooling agent; the liquid storage element is used to store the coolant; it can be connected so that when cooling is required, the solenoid valve is opened to fill part of the coolant into the cooling cavity through the hose 11; after the coolant vaporizes, it instructs the cooling element 5 to cool down quickly and maintains the air flow for a period of time to cool down; more specifically, an air temperature sensor is also provided in the cavity 6 to monitor the air flow temperature, and the air temperature sensor is electrically connected to the central control system of the film blowing machine; the central control system is electrically connected to the solenoid valve to control the opening and closing of the cooling, so that the central system can control the solenoid valve according to the temperature of the air flow; in another more detailed implementation scheme, the cooling cavity is also connected to a reflux pipe to recover the vaporized nitrogen.

[0046] More specifically, the connecting part 7 has an air guide channel 12 connecting the air duct 4 and the internal space of the cavity 6. The air guide channel 12 forms a guide path L, and the extension direction of the guide path L intersects with the surface of the metal ring to form a cooling angle β; wherein the cooling angle β is not greater than 30°; it can be understood that the setting of the air guide channel 12 makes the airflow and the surface of the cooling part 5 inclined; it can increase the contact area between the airflow and the cooling ring, thereby providing cooling efficiency.

[0047] More specifically, a Tesla valve 13 is provided at the junction of the nozzle 3 and the inner space of the cavity 6; since the flow velocity will decrease after the airflow collides with the cooling element 5, the flow velocity can be increased by providing the Tesla valve 13.

[0048] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0049] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A cooling device for plastic film blowing, which is installed on the film discharge air ring of the plastic film blowing machine to cool the plastic film being discharged; it is characterized by: include: a nozzle having a spray path for guiding an air flow to spray in a first direction; an air duct connecting the nozzle and the fan; a cooling element, located between the air duct and the nozzle to reduce the temperature of the air flow in the air duct; In which, a cavity connected to the nozzle is formed in the air ring, and the nozzles are arranged in a circular array along the circumferential direction of the air ring; a connecting piece is provided between the air duct and the cavity to connect the air duct and the internal space of the cavity; the cooling piece is fixedly provided in the cavity, located between the connecting piece and the nozzle; the cooling piece is filled with coolant.

2. A cooling device for plastic film blow molding according to claim 1, characterized in that: The cooling member is a metal ring formed by a metal structure; The metal ring extends along the extension direction of the cavity; Dragon scale patterns are formed on the surface of the metal ring; Wherein, the dragon scale pattern completely covers the surface of the metal ring.

3. A cooling device for plastic film blow molding according to claim 2, characterized in that: The cooling member forms a cooling cavity for the coolant to flow; The cooling chamber is connected to a liquid storage member storing coolant through a hose; Wherein, the liquid storage component is provided with a solenoid valve to control the flow / blocking of the hose.

4. A cooling device for plastic film blow molding according to claim 3, characterized in that: The connecting piece has an air guide channel connecting the air duct and the inner space of the cavity; The air guide channel forms a flow guide path; The extension direction of the guide path intersects with the surface of the metal ring to form a cooling angle; Wherein, the cooling angle is no greater than 30°.

5. A cooling device for plastic film blow molding according to claim 1, characterized in that: An air temperature sensor is also provided in the cavity to monitor the air flow temperature; The air temperature sensor is electrically connected to the central control system of the film blowing machine; The central control system is electrically connected to the cooling element to control the start / stop of cooling.

6. A cooling device for plastic film blow molding according to claim 1, characterized in that: The injection path forms an injection angle of 80°-90° with the surface of the air ring.

7. A cooling device for plastic film blow molding according to claim 1, characterized in that: A Tesla valve is provided at the junction of the nozzle and the inner space of the cavity.

8. A cooling device for plastic film blow molding according to claim 1, characterized in that: There are multiple connecting pieces, which are evenly arranged along the circumferential direction of the air ring.

9. A cooling device for plastic film blow molding according to claim 8, characterized in that: A flow diverter is provided between the air duct and the fan.

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