A preparation device of hot melt convex type pavement marking paint
Patent Information
- Application Number
- CN202522448960.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-19
- Publication Date
- 2026-10-23
- Estimated Expiration
- 2035-11-19
AI Technical Summary
当前常规的搅拌装置多采用单一转轴配合搅拌杆的结构,通过驱动电机带动转轴转动实现物料搅拌,但这类装置在实际应用中易出现物料粘附于搅拌罐体内壁及底面的问题
[0016]本实用新型的有益效果是:避免罐体内壁和底面物料残留影响后续搅拌效果,保证了搅拌均匀性,减少了原料损耗;提升了结构稳定性;提升了搅拌效率;减少了搅拌盲区;打破了物料流动惯性,进一步提升了搅拌效果;提高了刮除效果;增强了物料刮除的顺畅性与彻底性;提升了刮条对罐体表面的自适应贴合能力;阻挡了物料进入转套内部影响传动机构运行,保障装置传动稳定性与使用寿命;提高了转轴和侧轴安装稳定性;可实时直观观察内部物料搅拌状态与刮条工作情况。
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Figure CN224877883U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of road marking paint preparation process, and in particular to a preparation device for hot-melt raised road marking paint. Background Technology
[0002] Hot-melt raised pavement marking paint is widely used in road traffic safety facility construction due to its excellent anti-skid properties and visibility. Its preparation process requires a mixing device to ensure uniform mixing of raw materials and stable paint performance to meet subsequent construction and usage requirements. Currently, conventional mixing devices mostly use a single rotating shaft with a mixing rod, with a drive motor rotating the shaft to achieve material mixing. However, in practical applications, this type of device is prone to problems such as material adhering to the inner wall and bottom of the mixing tank.
[0003] In existing technologies, materials adhering to the inner wall and bottom of the mixing tank are difficult to remove using conventional mixing structures. Long-term accumulation can easily lead to material agglomeration, which not only affects the uniformity of subsequent mixing materials and reduces the quality of coating preparation, but also causes raw material waste and increases production costs.
[0004] In summary, there is a need for a device for preparing hot-melt raised pavement marking paint that can scrape the inner wall and bottom of the tank. Utility Model Content
[0005] The present invention aims to overcome the shortcomings of the prior art by providing a device for preparing hot-melt raised road marking paint that can scrape the inner wall and bottom of a tank.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: An apparatus for preparing a hot-melt raised pavement marking paint, comprising: Mixing tank; A rotating shaft is disposed inside the mixing tank and rotatably connected thereto. Several first stirring rods are fixed on the side wall of the rotating shaft. A drive motor connected to the top of the rotating shaft is installed and fixed on the top of the mixing tank. A turntable is provided on the inner bottom surface of the mixing tank and rotatably connected thereto. The turntable is provided with a rotating shaft movable groove that matches the bottom end of the rotating shaft. The bottom end of the rotating shaft is placed in the rotating shaft movable groove and rotatably connected thereto. A rotating sleeve is disposed on the inner top surface of the mixing tank and rotatably connected thereto. The rotating sleeve is located outside the rotating shaft and the two are connected by a transmission mechanism. A side plate is provided on the outside of the rotating sleeve. The top of the side plate is fixedly connected to the outer wall of the rotating sleeve by an upper plate, and the bottom of the side plate is fixedly connected to the side wall of the rotating platform by a lower plate. A side scraper is provided on the outer edge of the side plate to contact the inner wall of the mixing tank, and a bottom scraper is provided on the bottom edge of the lower plate to contact the bottom surface of the mixing tank.
[0007] During stirring, the drive motor rotates the rotating shaft and its first stirring rod to mix the materials in the mixing tank. Simultaneously, the transmission mechanism drives the rotating sleeve to rotate. The rotating sleeve, via the upper base plate, drives the side and lower base plates to rotate synchronously. The side and bottom scrapers, rotating with the side and lower base plates, scrape away materials adhering to the inner wall and bottom of the tank, preventing material residue from affecting subsequent stirring effects, ensuring uniform stirring, and reducing raw material loss. The top and bottom of the side base plates are fixed to the rotating sleeve and turntable via the upper and lower base plates, respectively, improving structural stability.
[0008] Preferably, a side shaft is also installed inside the mixing tank. The side shaft is located inside the rotating sleeve and on the side of the rotating shaft. Several second stirring rods are fixed on the side wall of the rotating shaft. The rotating shaft, side shaft, and rotating sleeve are connected by a transmission mechanism. When the rotating shaft rotates, the transmission mechanism drives the rotating sleeve and side shaft to move synchronously. The second stirring rods cooperate with the side shaft to achieve multi-directional stirring of the material in the tank, improving the uniformity and efficiency of stirring.
[0009] Preferably, the transmission mechanism includes a first gear, a second gear, and an annular internal gear. The first gear is sleeved and fixed on the rotating shaft, the second gear is sleeved and fixed on the side shaft, and the annular internal gear is fixed on the inner wall of the rotating sleeve. One side of the second gear meshes with the first gear, and the other side of the second gear meshes with the annular internal gear. The rotating shaft drives the first gear to rotate, and the second gear meshing with the first gear drives the annular internal gear and the rotating sleeve to move synchronously. The side shaft rotates in the opposite direction relative to the rotating shaft with the second gear, which, together with the second stirring rod, realizes multi-directional stirring of the material in the tank. The rotating sleeve rotates with the annular internal gear, driving the side scraper and bottom scraper to scrape off the material adhering to the inner wall and bottom surface of the tank.
[0010] Preferably, a plurality of third stirring rods are fixed on the inner side of the side substrate. The third stirring rods on the inner side of the side substrate rotate synchronously with the side substrate, forming a multi-dimensional stirring cooperation with the first and second stirring rods and the side shaft, further improving the uniformity of material mixing and reducing the stirring blind zone.
[0011] Preferably, a first rotating ring is rotatably sleeved on the first stirring rod, and a plurality of first driven rods are fixed on the first rotating ring. The first driven rods are circumferentially distributed on the outer side wall of the first rotating ring. A second rotating ring is rotatably sleeved on the second stirring rod, and a plurality of second driven rods are fixed on the second rotating ring. The second driven rods are circumferentially distributed on the outer side wall of the second rotating ring. A third rotating ring is rotatably sleeved on the third stirring rod, and a plurality of third driven rods are fixed on the third rotating ring. The third driven rods are circumferentially distributed on the outer side wall of the third rotating ring. The first stirring rod, the second stirring rod, and the third stirring rod are mutually adapted and arranged. The first stirring rod and the second stirring rod are staggered and the first driven rod and the second driven rod are staggered and arranged interlaced. The drive motor drives the rotating shaft to rotate, which in turn drives the side shaft and the side plate on the rotating sleeve to rotate synchronously through the transmission mechanism. This causes the first stirring rod, the second stirring rod, and the third stirring rod to rotate and stir. The first driven rod and the second driven rod, as well as the second driven rod and the third driven rod, collide with each other due to their interlacing contact, generating an impact force that drives the rotating rings on each stirring rod to rotate autonomously. The rotating rings further drive the driven rods to rotate synchronously, forming a compound action that combines active stirring and passive rotation. This breaks the inertia of material flow and further improves the stirring effect.
[0012] Preferably, one side of the side scraper contacts the inner wall of the mixing tank, and one side of the bottom scraper contacts the inner bottom surface of the mixing tank. Scraper mounting seats are fixed to the other sides of both the side and bottom scrapers. Scraper mounting grooves matching the mounting seats are provided on both the side base plate and the bottom base plate. The scraper mounting seats are placed within and rotatably connected to the scraper mounting grooves. Rotary pins are fixed to both ends of the scraper mounting seats. Rotary pin grooves matching the rotating pins are provided on the groove walls of the scraper mounting grooves. The rotating pins are placed within and rotatably connected to the rotating pin grooves. A torsion spring is provided inside the rotating pin grooves, and the end face of the rotating pin and the bottom surface of the rotating pin groove are connected by the torsion spring. The side and bottom scrapers are rotatably mounted via a rotating pin structure with a torsion spring, which adapts to the fit between the inner wall and bottom surface of the tank, improving the scraping effect.
[0013] Preferably, the side scraper is inclined in the direction of rotation and scraping from the side furthest from the inner wall of the mixing tank to the side closest to the inner wall of the mixing tank, and the bottom scraper is inclined in the direction of rotation and scraping from the side furthest from the bottom surface of the mixing tank to the side closest to the bottom surface of the mixing tank. The side and bottom scrapers are inclined in the scraping direction, and combined with the rotating mounting structure with a torsion spring, this enhances the smoothness and thoroughness of material scraping, and further improves the scraper's adaptive adhesion to the tank surface.
[0014] Preferably, the mixing tank is equipped with a protective plate that matches the rotating sleeve. The protective plate is positioned at the opening of the rotating sleeve, and is fixedly connected to the inner top surface of the mixing tank by a fixing post. The protective plate has a rotating shaft limiting through hole that matches the rotating shaft, and a side shaft limiting through hole that matches the side shaft. The protective plate is installed at the opening of the rotating sleeve by the fixing post, preventing material from entering the rotating sleeve and affecting the operation of the transmission mechanism, thus ensuring the transmission stability and service life of the device. Furthermore, the rotating shaft limiting through hole and the side shaft limiting through hole limit the rotation of the rotating shaft and the side shaft, improving the installation stability of the rotating shaft and the side shaft.
[0015] Preferably, an observation window is provided on the side wall of the mixing tank. The observation window on the side wall of the mixing tank allows for real-time and intuitive observation of the mixing status of the internal materials and the operation of the scraper.
[0016] The beneficial effects of this utility model are: it avoids material residue on the inner wall and bottom of the tank from affecting the subsequent stirring effect, ensuring stirring uniformity and reducing raw material loss; it improves structural stability; it improves stirring efficiency; it reduces stirring blind spots; it breaks the material flow inertia, further improving the stirring effect; it improves the scraping effect; it enhances the smoothness and thoroughness of material scraping; it improves the self-adaptive adhesion ability of the scraper to the tank surface; it prevents material from entering the inside of the rotating sleeve and affecting the operation of the transmission mechanism, ensuring the transmission stability and service life of the device; it improves the installation stability of the rotating shaft and side shaft; and it allows for real-time and intuitive observation of the internal material stirring status and scraper operation. Attached Figure Description
[0017] Figure 1 This is a perspective view of the present invention; Figure 2 This is the front view of this utility model; Figure 3 yes Figure 2 Sectional view at point AA; Figure 4 yes Figure 3 Enlarged view of point B in the middle; Figure 5 yes Figure 3 Enlarged view of point C in the middle; Figure 6 This is a schematic diagram of the wiping direction of the side scraper from a top-down view; Figure 7 This is a schematic diagram of the scraping direction of the bottom scraper when viewed from above.
[0018] In the diagram: 1. Mixing tank body, 2. Rotating shaft, 3. First stirring rod, 4. Drive motor, 5. Turntable, 6. Rotating sleeve, 7. Side base plate, 8. Upper base plate, 9. Lower base plate, 10. Side scraper, 11. Bottom scraper, 12. Side shaft, 13. Second stirring rod, 14. First gear, 15. Second gear, 16. Annular internal gear, 17. Third stirring rod, 18. First rotating ring, 19. First driven rod, 20. Second rotating ring, 21. Second driven rod, 22. Third rotating ring, 23. Third driven rod, 24. Scraper mounting seat, 25. Scraper mounting groove, 26. Rotating pin, 27. Rotating pin groove, 28. Torsion spring, 29. Protective plate, 30. Fixed column, 31. Observation window. Detailed Implementation
[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0020] like Figure 1 , Figure 2 and Figure 3 In the embodiments described above, an apparatus for preparing hot-melt raised pavement marking paint includes: Mixing tank 1; like Figure 3 and Figure 4 As shown, a rotating shaft 2 is located inside the mixing tank 1 and is rotatably connected to it. Several first stirring rods 3 are fixed on the side wall of the rotating shaft 2. A drive motor 4 connected to the top of the rotating shaft 2 is installed and fixed on the top of the mixing tank 1. Turntable 5 is set on the inner bottom surface of the mixing tank 1 and is rotatably connected to it. Turntable 5 is provided with a rotating shaft movable groove that matches the bottom end of the rotating shaft 2. The bottom end of the rotating shaft 2 is placed in the rotating shaft movable groove and is rotatably connected to it. Rotating sleeve 6 is disposed on the inner top surface of the mixing tank 1 and rotatably connected thereto. The rotating sleeve 6 is located outside the rotating shaft 2 and the two are connected by a transmission mechanism. Side base plate 7 is disposed on the outside of rotating sleeve 6. The top of side base plate 7 is fixedly connected to the outer wall of rotating sleeve 6 via upper base plate 8, and the bottom of side base plate 7 is fixedly connected to the side wall of rotating platform 5 via lower base plate 9. Side scraper 10 is provided on the outer edge of side base plate 7 to contact the inner wall of mixing tank 1, and bottom scraper 11 is provided on the bottom edge of lower base plate 9 to contact the bottom surface of mixing tank 1. The number of side base plates 7 can be one or several distributed circumferentially on the outside of rotating shaft 2 with rotating shaft 2 as the center.
[0021] The mixing tank 1 is also equipped with a side shaft 12, which is located inside the rotating sleeve 6 and on the side of the rotating shaft 2. Several second stirring rods 13 are fixed on the side wall of the rotating shaft 2. The rotating shaft 2, the side shaft 12, and the rotating sleeve 6 are connected by a transmission mechanism. The side shaft 12 can be a single shaft or several shafts circumferentially distributed around the rotating shaft 2.
[0022] The transmission mechanism includes a first gear 14, a second gear 15, and an annular internal gear 16. The first gear 14 is sleeved and fixed on the rotating shaft 2, the second gear 15 is sleeved and fixed on the side shaft 12, and the annular internal gear 16 is fixed on the inner side wall of the rotating sleeve 6. One side of the second gear 15 meshes with the first gear 14, and the other side of the second gear 15 meshes with the annular internal gear 16.
[0023] Several third stirring rods 17 are fixed on the inner side of the side plate 7.
[0024] A first rotating ring 18 is rotatably sleeved on the first stirring rod 3. Several first driven rods 19 are fixed to the first rotating ring 18, and the first driven rods 19 are circumferentially distributed on the outer wall of the first rotating ring 18. A second rotating ring 20 is rotatably sleeved on the second stirring rod 13. Several second driven rods 21 are fixed to the second rotating ring 20, and the second driven rods 21 are circumferentially distributed on the outer wall of the second rotating ring 20. A third rotating ring 22 is rotatably sleeved on the third stirring rod 17. Several third driven rods 23 are fixed on the third rotating ring 22. The third driven rods 23 are circumferentially distributed on the outer side wall of the third rotating ring 22. The first stirring rod 3, the second stirring rod 13, and the third stirring rod 17 are mutually adapted. The first stirring rod 3 and the second stirring rod 13 are staggered, and the first driven rod 19 and the second driven rod 21 are staggered. The second stirring rod 13 and the third stirring rod 17 are staggered, and the second driven rod 21 and the third driven rod 23 are staggered.
[0025] like Figure 3 and Figure 5 As shown, one side of the side scraper 10 is in contact with the inner wall of the mixing tank 1, and one side of the bottom scraper 11 is in contact with the inner bottom surface of the mixing tank 1. Scraper mounting seats 24 are fixed on the other side of the side scraper 10 and the other side of the bottom scraper 11. Scraper mounting grooves 25 matching the scraper mounting seats 24 are provided on the side base plate 7 and the lower base plate 9. The scraper mounting seats 24 are placed in the scraper mounting grooves 25 and rotatably connected to them. Rotary pins 26 are fixed at both ends of the scraper mounting seats 24. Rotary pin grooves 27 matching the rotary pins 26 are provided on the groove wall of the scraper mounting grooves 25. The rotary pins 26 are placed in the rotary pin grooves 27 and rotatably connected to them. A torsion spring 28 is provided inside the rotary pin grooves 27. The end face of the rotary pin 26 and the bottom face of the rotary pin grooves 27 are connected by the torsion spring 28.
[0026] like Figure 6 and Figure 7 As shown, the side scraper 10 is inclined from the side away from the inner wall of the mixing tank 1 to the side close to the inner wall of the mixing tank 1 in the direction of rotation and scraping of the side scraper 10, and the bottom scraper 11 is inclined from the side away from the bottom surface of the mixing tank 1 to the side close to the bottom surface of the mixing tank 1 in the direction of rotation and scraping of the bottom scraper 11.
[0027] The mixing tank 1 is equipped with a protective plate 29 that matches the rotating sleeve 6. The protective plate 29 is placed at the opening of the rotating sleeve 6. The protective plate 29 and the inner top surface of the mixing tank 1 are fixedly connected by a fixing column 30. The protective plate 29 is provided with a rotating shaft limiting through hole that matches the rotating shaft 2, and the protective plate 29 is provided with a side shaft limiting through hole that matches the side shaft 12.
[0028] An observation window 31 is provided on the side wall of the mixing tank 1.
[0029] During stirring, the drive motor 4 drives the rotating shaft 2 and the first stirring rod 3 on it to rotate, mixing the materials in the stirring tank 1. At the same time, the rotating shaft 2 drives the first gear 14 to rotate. The second gear 15, which meshes with the first gear 14, drives the annular internal gear 16 and the rotating sleeve 6 to move synchronously. The side shaft 12 rotates in the opposite direction to the rotating shaft 2 with the second gear 15 and the side base plate 7 with the annular internal gear 16 on the rotating sleeve 6. This, together with the second stirring rod 13 and the third stirring rod 17, achieves multi-dimensional stirring of the materials in the stirring tank 1. During the rotation and stirring process of the first stirring rod 3, the second stirring rod 13, and the third stirring rod 17, the first driven rod 19 and the second driven rod 21, and the second driven rod 21 and the third driven rod 23 collide due to their intersecting contact, generating an impact force that drives the rotating rings on each stirring rod to rotate autonomously. The rotating rings further drive the driven rods to rotate synchronously, forming a compound action that combines active stirring and passive rotation. This breaks the inertia of material flow and further improves the stirring effect.
[0030] The top and bottom ends of the side plate 7 are respectively mounted and fixed on the rotating sleeve 6 and the turntable 5 via the upper plate 8 and the lower plate 9. When the rotating sleeve 6 drives the side plate 7 and the lower plate 9 to rotate synchronously via the upper plate 8, the side scraper 10 and the bottom scraper 11 rotate with the side plate 7 and the lower plate 9 to scrape off the material adhering to the inner wall and bottom surface of the mixing tank 1, thus avoiding material residue on the inner wall and bottom surface of the tank. The side scraper 10 and the bottom scraper 11 are inclined towards the scraping direction. With the rotating mounting structure with torsion spring 28, the smoothness and thoroughness of material scraping are enhanced, and the self-adaptive adhesion ability of the scraper to the surface of the tank is further improved.
Claims
1. An apparatus for preparing a hot-melt raised pavement marking paint, characterized in that it comprises: Mixing tank (1); A rotating shaft (2) is located inside the mixing tank (1) and is rotatably connected to it. Several first stirring rods (3) are fixed on the side wall of the rotating shaft (2). A drive motor (4) connected to the top of the rotating shaft (2) is installed and fixed on the top of the mixing tank (1). Turntable (5), the turntable (5) is set on the inner bottom surface of the mixing tank (1) and rotatably connected thereto. The turntable (5) is provided with a rotating shaft movable groove that matches the bottom end of the rotating shaft (2). The bottom end of the rotating shaft (2) is placed in the rotating shaft movable groove and rotatably connected thereto. Rotating sleeve (6), the rotating sleeve (6) is disposed on the inner top surface of the mixing tank (1) and rotatably connected thereto, the rotating sleeve (6) is located outside the rotating shaft (2) and the two are connected by a transmission mechanism; Side base plate (7), the side base plate (7) is disposed on the outside of the rotating sleeve (6), the top of the side base plate (7) and the outer side wall of the rotating sleeve (6) are fixedly connected by the upper base plate (8), the bottom of the side base plate (7) and the side wall of the turntable (5) are fixedly connected by the lower base plate (9), the outer side of the side base plate (7) is provided with a side scraper (10) that contacts the inner side wall of the mixing tank (1), and the bottom side of the lower base plate (9) is provided with a bottom scraper (11) that contacts the bottom surface of the mixing tank (1).
2. The apparatus for preparing hot-melt raised pavement marking paint according to claim 1, characterized in that, The mixing tank (1) is also equipped with a side shaft (12). The side shaft (12) is placed inside the rotating sleeve (6) and located on the side of the rotating shaft (2). Several second stirring rods (13) are fixed on the side wall of the rotating shaft (2). The rotating shaft (2), the side shaft (12), and the rotating sleeve (6) are connected by a transmission mechanism.
3. The apparatus for preparing hot-melt raised pavement marking paint according to claim 2, characterized in that, The transmission mechanism includes a first gear (14), a second gear (15), and an annular internal gear (16). The first gear (14) is sleeved and fixed on the rotating shaft (2), the second gear (15) is sleeved and fixed on the side shaft (12), and the annular internal gear (16) is fixed on the inner side wall of the rotating sleeve (6). One side of the second gear (15) meshes with the first gear (14), and the other side of the second gear (15) meshes with the annular internal gear (16).
4. The apparatus for preparing hot-melt raised pavement marking paint according to claim 2, characterized in that, Several third stirring rods (17) are fixed on the inner side of the side plate (7).
5. The apparatus for preparing hot-melt raised pavement marking paint according to claim 4, characterized in that, A first rotating ring (18) is rotatably sleeved on the first stirring rod (3). Several first driven rods (19) are fixed to the first rotating ring (18). The first driven rods (19) are circumferentially distributed on the outer wall of the first rotating ring (18). A second rotating ring (20) is rotatably sleeved on the second stirring rod (13). Several second driven rods (21) are fixed to the second rotating ring (20). The second driven rods (21) are circumferentially distributed on the outer wall of the second rotating ring (20). A third rotating ring (22) is rotatably sleeved on the third stirring rod (17). A number of third driven rods (23) are fixed on the three rotating rings (22). The third driven rods (23) are circumferentially distributed on the outer side wall of the third rotating rings (22). The first stirring rod (3), the second stirring rod (13), and the third stirring rod (17) are mutually adapted. The first stirring rod (3) and the second stirring rod (13) are staggered, and the first driven rod (19) and the second driven rod (21) are staggered. The second stirring rod (13) and the third stirring rod (17) are staggered, and the second driven rod (21) and the third driven rod (23) are staggered.
6. The apparatus for preparing hot-melt raised pavement marking paint according to claim 1, characterized in that, One side of the side scraper (10) is in contact with the inner wall of the mixing tank (1), and one side of the bottom scraper (11) is in contact with the inner bottom surface of the mixing tank (1). Scraper mounting seats (24) are fixed to the other side of both the side scraper (10) and the bottom scraper (11). Scraper mounting grooves (25) matching the scraper mounting seats (24) are provided on both the side base plate (7) and the lower base plate (9). The scraper mounting seats (24) are placed on the scraper mounting bases. The scraper mounting base (24) is fixed with pivot pins (26) at both ends. The scraper mounting groove (25) is provided with pivot pin grooves (27) that match pivot pins (26). The pivot pin (26) is placed in the pivot pin groove (27) and is rotatably connected to it. The pivot pin groove (27) is provided with torsion springs (28) inside. The end face of the pivot pin (26) and the bottom face of the pivot pin groove (27) are connected by torsion springs (28).
7. The apparatus for preparing hot-melt raised pavement marking paint according to claim 6, characterized in that, The side scraper (10) is inclined from the side away from the inner wall of the mixing tank (1) to the side close to the inner wall of the mixing tank (1) in the direction of rotation and scraping of the side scraper (10), and the bottom scraper (11) is inclined from the side away from the bottom surface of the mixing tank (1) to the side close to the bottom surface of the mixing tank (1) in the direction of rotation and scraping of the bottom scraper (11).
8. The apparatus for preparing hot-melt raised pavement marking paint according to claim 2, characterized in that, The mixing tank (1) is provided with a protective plate (29) that matches the rotating sleeve (6). The protective plate (29) is placed at the opening of the rotating sleeve (6). The protective plate (29) and the inner top surface of the mixing tank (1) are fixedly connected by a fixing column (30). The protective plate (29) is provided with a rotating shaft limiting through hole that matches the rotating shaft (2). The protective plate (29) is provided with a side shaft limiting through hole that matches the side shaft (12).
9. The apparatus for preparing hot-melt raised pavement marking paint according to claim 1, characterized in that, An observation window (31) is provided on the side wall of the mixing tank (1).