A powder coating extruder

Abstract

The utility model discloses a kind of powder coating extruders, belong to powder coating production equipment technical field, including extruder head and the extrusion outlet of its end part, further including cleaning scraper, the cleaning scraper includes scraper ring body and driving device, the scraper ring body is movably housed in extrusion outlet, at least one longitudinal guide slot is opened in the pipe wall of the extrusion outlet, guide portion is arranged on the scraper ring body and can slide up and down in guide slot, the driving device is fixedly arranged in the outside of extruder head, its output end is drivingly connected with guide portion, to drive guide portion to drive scraper ring body reciprocating linear motion in extrusion outlet;The utility model is driven by driving device along guide slot accurate reciprocating motion by being provided with cleaning scraper with scraping strip and flexible sealing ring, realizes the on-line automatic cleaning and sealing anti-blocking of extrusion outlet, combined with optional air blowing and timing control system, it reaches the effect of high-efficiency removal of residual material together.

Description

Technical Field

[0001] This utility model relates to the technical field of powder coating production equipment, specifically a powder coating extruder. Background Technology

[0002] In the powder coating production process, the extruder is a key piece of equipment. Through screw shearing and barrel heating, it melts, mixes, and homogenizes powder raw materials such as resin, curing agent, and pigments, then extrudes them from the extruder nozzle for subsequent processing to produce the finished product. During normal powder coating production, the molten and mixed materials are continuously extruded from the nozzle and cooled by cooling rollers to form strips or sheets of intermediate products. However, when the equipment is shut down (e.g., for color changes or maintenance), the material trapped inside the extruder nozzle loses its extrusion power and remains in a high-temperature molten state, resulting in a viscous, semi-fluid state. As the equipment cools, this material gradually solidifies into a hard blockage, severely impacting equipment utilization efficiency and production continuity. Currently, the mainstream cleaning method relies on manual operation, requiring the extruder nozzle to be disassembled and manually scraped after the machine has cooled down. This process is time-consuming and labor-intensive, and incomplete cleaning can easily lead to cross-contamination of products. There are also safety risks such as burns to operators due to contact with high-temperature parts and tools, significantly affecting production safety and efficiency.

[0003] While existing technologies include solutions that use extrusion outlet cooling devices to delay material solidification, this method only slows down the process and cannot fundamentally prevent solidification. Furthermore, manual intervention is still required during color changes after shutdown, so the problem remains unresolved. Other solutions attempt to improve material flow by optimizing the barrel design, but these do not address the core pain point of efficient online cleaning after blockages, thus failing to effectively reduce downtime and improve production efficiency.

[0004] Therefore, there is an urgent need for a powder coating extruder that can clean the extrusion nozzle online, fundamentally preventing material solidification and blockage. Utility Model Content

[0005] The purpose of this invention is to overcome the aforementioned technical difficulties and provide a powder coating extruder that can clean the extrusion nozzle online, thereby fundamentally preventing material solidification and blockage.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a powder coating extruder includes an extruder head and an extrusion port at its end, and a cleaning scraper. The cleaning scraper includes a scraper ring body and a driving device. The scraper ring body is movably accommodated in the extrusion port. At least one longitudinal guide groove is provided on the wall of the extrusion port. The scraper ring body is provided with a guide portion that is embedded in the guide groove and can slide up and down along it. The driving device is fixedly installed outside the extruder head, and its output end is connected to the guide portion for transmission, so as to drive the guide portion to drive the scraper ring body to reciprocate linearly within the extrusion port.

[0007] Furthermore, a scraper strip is provided on the outer wall of the scraper ring body.

[0008] Furthermore, a flexible sealing ring is also fitted on the outer wall of the scraper ring body.

[0009] Furthermore, the flexible sealing ring is provided with a central air passage and a purge hole, and the cleaning scraper is provided with a central air passage that is connected to an external air source through a rotary pneumatic connector.

[0010] Furthermore, a control valve is provided in the central air circuit, which is controlled by a timer controller to synchronously open the external air source when the drive device is activated.

[0011] Furthermore, the guide portion is a protrusion or pin that is integrally formed or fixedly connected to the scraper ring body.

[0012] Furthermore, the drive device is electrically connected to a timer controller, which is used to preset the cleaning cycle and control the drive device to run automatically at set time intervals.

[0013] The powder coating extruder provided by this utility model has the following beneficial effects: This invention achieves online automatic cleaning and sealing of the extrusion nozzle by setting a cleaning scraper with a scraper and a flexible sealing ring, and driving it to move precisely back and forth along the guide groove by a drive device. Combined with an optional air blowing and timing control system, it achieves the effect of efficiently removing residual materials. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the powder coating extruder of this utility model.

[0015] Figure 2 This is a schematic diagram of the cleaning scraper for the powder coating extruder of this utility model.

[0016] Figure 3 This is a schematic diagram of the guide groove of the powder coating extruder of this utility model.

[0017] Figure 4 This is a schematic diagram of the scraper ring body of the powder coating extruder of this utility model.

[0018] In the diagram, 1. Extruder head; 2. Extrusion port; 3. Cleaning scraper; 31. Scraper ring body; 4. Drive unit; 5. Guide groove; 6. Guide section; 7. Scraper strip; 8. Flexible sealing ring; 9. Timer controller; 10. Central air passage. Detailed Implementation

[0019] The technical solution of this utility model will be clearly and completely described below with reference to specific embodiments. The described embodiments are merely some, not all, of these embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0020] Example 1 like Figure 1-4 As shown, the powder coating extruder provided by this utility model initiates a cleaning program when the material is still in or about to be in a semi-fluid state, thereby achieving efficient online anti-clogging. It includes an extruder head 1 and an extrusion port 2 at its end. The outer diameter of the head of the extruder head 1 that is fitted with the extrusion port 2 is smaller than the inner diameter of the extrusion port 2. The extrusion port 2 has a cylindrical structure and is used to guide the molten mixed material to downstream equipment. This embodiment also includes a cleaning scraper 3, which includes a scraper ring body 31 and a driving device 4. The scraper ring body 31 is movably housed in the extrusion port 2. The scraper ring body 31 is made of a high-temperature resistant, wear-resistant, and self-lubricating material, such as polytetrafluoroethylene or polyetheretherketone. There is a gap of 0.5 mm to 2 mm between its outer diameter and the inner diameter of the extrusion port 2 to ensure that it can slide freely inside without being jammed.

[0021] At least one longitudinal guide groove 5 is provided on the wall of the extrusion port 2. The scraper ring body 31 is provided with a guide part 6 that is embedded in the guide groove 5 and can slide up and down along it. The guide part 6 is a protrusion or pin that is integrally formed or fixedly connected to the scraper ring body 31. While it can slide up and down along the guide groove 5, it effectively prevents the scraper ring body 31 from rotating circumferentially in the extrusion port 2.

[0022] The drive device 4 is fixedly installed outside the extruder head 1, and its output end is connected to the guide part 6 for transmission, so as to drive the guide part 6 to drive the scraper ring body 31 to perform reciprocating linear motion in the extrusion port 2. In this embodiment, a double-acting small cylinder is preferred, and the end of its piston rod is hinged to the guide part 6 through a fisheye joint, thereby converting the reciprocating linear motion of the cylinder piston rod into the precise reciprocating linear motion of the scraper ring body 31 in the inner cavity of the extrusion port 2. When cleaning is required, the operator manually controls the drive device 4 to operate through an external pneumatic switch, driving the scraper ring body 31 to move up and down, and using the mechanical scraping action between the scraper ring body 31 and the inner wall of the extrusion port 2 to remove residual material from the inner wall of the extrusion port 2.

[0023] Example 2 Based on Example 1, this embodiment further optimizes the structure of the scraper ring body 31 to improve the cleaning effect. A scraper strip 7 is provided on the outer wall of the scraper ring body 31, with its cutting edge in line contact with the inner wall of the extrusion port 2 to provide higher local pressure. Preferably, the scraper strip 7 is configured as two strips, an upper scraper strip 7 and a lower scraper strip 7, to complete two scraping operations in one stroke for more thorough cleaning. In this embodiment, a flexible sealing ring 8 is also fitted on the outer wall of the scraper ring body 31, between the scraper strips 7. This flexible sealing ring 8 is made of high-temperature resistant silicone rubber or perfluororubber, and its natural outer diameter is slightly larger than the inner diameter of the extrusion port 2, forming an interference fit. This flexible sealing ring 8 is designed to better scrape away viscous, semi-molten material films and, when the extruder is working normally, tightly adheres to the inner wall of the extrusion port 2, thereby forming an effective dynamic seal and preventing high-pressure melt from seeping into the guide groove 5. This fundamentally solves the potential sealing problem of the guide groove 5 and prevents the scraper from jamming due to material seepage.

[0024] Furthermore, the sealing principle of the flexible sealing ring 8 is as follows: When the extruder is working normally, the inside of the die head is under high pressure. This pressure acts on the side of the flexible sealing ring 8, forcing it to undergo slight radial expansion, thereby causing its outer edge to press more tightly against the inner wall of the extrusion port 2, forming a high-pressure sealing band. This sealing band can completely cover the inlet of the guide groove 5, thereby effectively preventing high-pressure molten material from entering the interior of the guide groove 5.

[0025] Example 3 Based on Example 2, the flexible sealing ring 8 in this example has an internal air passage and multiple micro-purge holes with a diameter of approximately 0.5mm-1mm. The cleaning scraper 3 has a central air passage 10 connected to an external air source via a rotary pneumatic connector. A control valve is installed on the central air passage 10, controlled by a timer controller 9, to synchronously open the external air source when the drive device 4 is activated. The drive device 4 is electrically connected to the timer controller 9, which presets the cleaning cycle and controls the drive device 4 to operate automatically at set time intervals.

[0026] In this embodiment, in addition to performing the dynamic sealing and scraping functions described in Embodiment 2, the flexible sealing ring 8 also provides assistance during the cleaning process through its integrated air blowing system. When the cleaning command is triggered, compressed air is ejected from the blow-out hole. The airflow is not only used to clean the inner wall of the extrusion port 2, but also to perform reverse blowing on the inlet area of ​​the guide groove 5, further eliminating any long-term risk of scraper jamming due to material seepage.

[0027] Operating principle: When cleaning is required, the timer controller 9 automatically triggers the process according to a preset program, or the operator can manually initiate it. The timer controller 9 synchronously sends commands to the drive unit 4 and the air control valve. The drive unit 4 then drives the cleaning scraper 3 to reciprocate linearly within the extrusion port 2. The scraper blade 7 and flexible sealing ring 8 on the scraper mechanically scrape and seal the inner wall of the extrusion port 2. Simultaneously, the air control valve opens, and compressed air passes through the rotary pneumatic connector, the central air passage 10, and the intermediate air channel, finally being ejected at high speed from the blowhole. This airflow forms an air curtain in front of the scraper blade 7, assisting in the removal of material and preventing its re-adhesion. It also forcibly blows away any scraped residue from the cleaning area, achieving coordinated and efficient cleaning. After one cycle, all components reset.

[0028] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

[0029] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A powder coating extruder, comprising an extruder head (1) and an extrusion port (2) at its end, characterized in that: It also includes a cleaning scraper (3), which includes a scraper ring body (31) and a drive device (4). The scraper ring body (31) is movably housed in the extrusion port (2). At least one longitudinal guide groove (5) is provided on the tube wall of the extrusion port (2). The scraper ring body (31) is provided with a guide part (6) that is embedded in the guide groove (5) and can slide up and down along it. The drive device (4) is fixedly installed outside the extruder head (1), and its output end is connected to the guide part (6) for transmission, so as to drive the guide part (6) to drive the scraper ring body (31) to make reciprocating linear motion in the extrusion port (2).

2. The powder coating extruder according to claim 1, characterized in that: A scraper (7) is provided on the outer wall of the scraper ring body (31).

3. The powder coating extruder according to claim 2, characterized in that: A flexible sealing ring (8) is also fitted on the outer wall of the scraper body (31).

4. The powder coating extruder according to claim 3, characterized in that: The flexible sealing ring (8) is provided with a central air passage and a purge hole, and the cleaning scraper (3) is provided with a central air passage (10) that is connected to an external air source through a rotating pneumatic connector.

5. The powder coating extruder according to claim 4, characterized in that: The central air passage (10) is equipped with a control valve, which is controlled by a timer controller (9) to simultaneously open the external air source when the drive device (4) is activated.

6. The powder coating extruder according to claim 1, characterized in that: The guide part (6) is a protrusion or pin that is integrally formed or fixedly connected to the scraper ring body (31).

7. The powder coating extruder according to claim 1, characterized in that: The drive device (4) is electrically connected to a timer controller (9), which is used to preset the cleaning cycle and control the drive device (4) to run automatically at the set time interval.

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