CN1817618A - Method and apparatus for online rotary spraying in films - Google Patents

Abstract

The invention discloses an internal on-line rotary spraying process and device of flat extrusion blown film bubbles, which belongs to the object surface coating process. The device consists of three parts: 1. Rotary sprayer host, 2. Mechanical arm, 3. High-pressure airless sprayer; by adjusting the speed of the host, the distance between the nozzle on the mechanical arm and the surface of the object, and the pressure of the functional coating liquid, The flow rate will evenly coat a proper amount of spray liquid on the surface of the upward moving film. The present invention is designed for the production equipment and process of flat extrusion blown plastic film. It is coated just above the cooling line in the film bubble on the production line. The quenching effect is good, the plastic crystallization is refined, and the transparency and function of the film are improved. The adhesion of the coating to the surface of the film increases the durability of the functional coating. The device can be installed on the up-blowing film blowing machine with or without internal cooling device, and the capital investment is small; there is no need to change the existing flat extrusion up-blowing production process; no need to increase the production site. It is especially suitable for the technological transformation of the existing agricultural film production equipment in our country.

Description

On-line rotary spraying process and device for flat extrusion blown film bubble

Technical field:

The invention relates to a rotary spraying process and device for object surfaces, in particular to a rotary spraying process and device for synchronously coating the inner surface of a closed cylindrical film bubble with a functional coating during the production process of flat extrusion blown plastic film ; Different functional spraying liquids can be selected to produce films with different functions. It is especially suitable for the production of dripping and fog-eliminating shed films for agriculture and planting.

Background technique:

The production of polyethylene shed film in my country is almost flat extrusion and blow molding process. The traditional way to improve the dripping and defogging performance of the shed film is to add a dripping and defogging agent to the shed film; but the shed film produced by this method has The dripping and defogging function has a short duration and will reduce the strength and weather resistance of the greenhouse film. In recent years, it has been found that coating the inner surface of the shed film with a long-lasting dripping anti-fog agent is an effective way, which can not only greatly extend the duration of the dripping anti-fog of the shed film and reduce production costs, but also will not reduce the cost of the shed film. strength and weather resistance. At present, domestic agricultural shed film production enterprises mainly try the online spraying process from the following two aspects: 1. Extrusion upward blow molding online spraying and drying from the outer surface of the shed film and then winding online spraying process; 2. Extrusion downward Blow molding, the spraying pipe is led out from the head of the blow molding machine, and the spray nozzle is used to continuously spray the liquid dripping anti-fog agent on the shaped film from the center of the film bubble in a radial direction, and the nozzle is automatically controlled according to the size of the film bubble. online spraying process. These two methods either increase the production site and add drying equipment; or completely change the original production process. Capital investment is large, and it is difficult to promote.

Invention content:

Aiming at the current situation that the production of polyethylene shed film in my country is almost flat extrusion blow molding process, and the current online spraying technology transformation scheme is too difficult to promote, the present invention provides a flat extrusion top blown film bubble internal on-line rotary spraying process and device . Its characteristics are: 1. Small capital investment; no need to change the existing flat extrusion up-blowing production process; no need to increase the production site; 2. In the case of online production, the inner surface of the film bubble is evenly rotated on the cooling line to coat the functional coating liquid .

The technical solution adopted by the present invention to solve the technical problem is: the device is composed of three major parts: 1. the main frame of the rotary spraying machine, 2. the mechanical arm, and 3. the high-pressure airless spraying machine; if the original machine head has an internal cooling device, first Cut off the suction column at an appropriate height, build a platform whose size is smaller than the diameter of the die, and then install the main engine of the rotary spraying machine in the center above it. If the original machine head has no internal cooling device, the main engine of the rotary spraying machine can be installed in the center of the die. The height of the nozzle is above the cooling line of the film bubble; after the film is extruded, it moves upward at a constant speed under the traction of the tractor, forming a cylindrical airtight film bubble above the die. At this time, start the device, the nozzle of the rotary spraying main engine rotates on the inner surface of the film bubble, adjust the expansion and contraction of the mechanical arm, and apply an appropriate amount of spraying liquid evenly on the surface of the upward moving film. If there is an internal cooling device, use the residual heat in the film bubble The water in the spraying liquid is evaporated, and the hot and humid gas is drawn out of the film bubble by the internal cooling. If there is no internal cooling device, the functional coating liquid will be kept in the film.

The technical core of the present invention is the main machine of the rotary spraying machine, which is composed of a rotary joint, a frequency conversion motor, a worm gear transmission box, a circuit rotary connector and an electric telescopic rod. It reasonably solves the technical problem of connecting and transporting high-pressure spraying liquid and circuit wires from the stationary end to the high-speed rotating end. Reasonable structure, stable rotation and adjustable speed. A spray head with outward nozzles is installed on at least two ends of the mechanical arms near the film. The mechanical arms can be stretched and retracted in the axial direction at the same time, and the distance between the spray head and the film can be adjusted arbitrarily. At least one high-pressure airless sprayer is connected with the host of the rotary sprayer, and the flow rate is adjustable. The spray width is adjustable and the pressure is adjustable.

Beneficial effect:

1. Since the rotation speed, the flow rate of the spray liquid, the spray width, and the spray distance can be adjusted arbitrarily, it can meet the online spraying of films of different specifications and sizes, and there will be no dead angle of spraying;

2. Since the invention uses high-pressure airless rotary spraying, the problem of spraying liquid rebounding is completely avoided, and the coating is more uniform than other spraying methods, and spraying liquid will not be wasted. It will not change the original constant pressure inside the bubble.

3. Due to the beneficial effects of 1 and 2, it effectively solves the problem that the film bubble cannot be inflated when the excessive spray liquid flows down along the inner wall of the film bubble and exceeds the cooling line, so there is no need to change the production process of upward blow molding, and no need Increase the production site, the capital investment is small, especially suitable for the online spraying transformation of the existing film production equipment in our country.

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Accompanying drawing: Schematic diagram of the working state of the embodiment of the device

Detailed ways

Install the device as shown in the accompanying drawing.

Before the blown film pulls up the film bubble 16, determine the height of the film bubble cooling line 20 according to the width and thickness of the film, adjust the nozzle lift regulator 4,5 to ensure that the lowest position of the spray width of the nozzles 9,10 is on the cooling line 20 above. Start the high-pressure airless sprayer 13, make the function coating liquid slow high-pressure liquid delivery pipes 6, 7, 8 until the spray widths 11, 12 appear in the nozzles 9, 10, then close the high-pressure airless sprayer 13 for standby. Restart the film blowing machine and when the film bubble 16 reaches the width and thickness requirements, start the rotating main machine 1 and the mechanical arms 2 and 3 by rotating the main machine console 14, and the mechanical arms 2 and 3 start to rotate under the action of the rotating main machine 1 and simultaneously Stretch out, when the nozzles 9 and 10 installed on the mechanical arm are close to the inner wall of the film bubble 16, start the high-pressure airless sprayer 13 to start rotating spraying. Observe the condition of the coating, and properly adjust the rotation speed of the rotary host 1 or the pressure and flow rate of the high-pressure airless sprayer 13 or the distance between the nozzles 9, 10 and the film bubble 16 to achieve a satisfactory coating effect.

This device can be installed on the up-blowing film blowing machine with or without internal cooling device. For film blowing machines with internal cooling device, the suction pipe 18 of the internal cooling device can be cut off at 1500mm, and this device can be installed on the rotating host installation platform 19. device. For film blowing machines without internal cooling device, this device is directly installed on the die platform 21.

Claims (5)

1. online rotary spraying in films technology and device, it is characterized in that according on blow cylindrical membrane bubble upward speed, the nozzle and the film that are installed on the mechanical arm by adjusting steep the distance of inwall and pressure, spraying swath, flow, the rotary spraying speed of spray coating liquor, realize the even coating functions masking liquid to body surface.

2. online rotary spraying in films device according to claim 1, it is characterized in that blowing the cross-head upper shaft to the rotary spraying machine mainframe box is installed flat squeezing into, mechanical arm radially is installed on the mainframe box, the shower nozzle elevation and subsidence regulating device is installed on the mechanical arm, shower nozzle is installed on the elevation and subsidence regulating device, outside the film bubble, high pressure airless spray equipment and control device are installed, the function masking liquid are transported to shower nozzle by pressure piping.

3. online rotary spraying in films device according to claim 2 is characterized in that installing on the rotating shaft in the rotary spraying machine mainframe box the above swivel joint of at least one passage; At least two above circuit carbon brush that connect mechanical arm of path; At least one telescopic mechanical arm; The above elevation and subsidence regulating device of at least one cover; At least more than one shower nozzle (nozzle).High pressure airless spray equipment more than at least one.At least one highly pressurised liquid conveyance conduit that installs vertically and at least one group of supply line on the handpiece body.

4. online rotary spraying in films device according to claim 3 is characterized in that the position of shower nozzle (nozzle) is installed in more than the cooling line of film bubble, and can regulate the position of shower nozzle (nozzle) by elevation and subsidence regulating device.

5. according to claim 1,2,3,4 described online rotary spraying in films devices, it is characterized in that carrying to round end by stationary end by swivel joint, carbon brush circuit realization function masking liquid and power supply; Airless spraying is used to have the interior spraying of film bubble of constant voltage, can not exert an influence to original pressure in the film bubble.

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