Positioning tool for gold stamping of packaging bottle

By designing a packaging bottle positioning tool with sliding and rotating structure, the problem that the existing positioning tool cannot adjust the position of the packaging bottle is solved, and flexible adjustment of height and position is achieved, improving the flexibility and convenience of use.

CN222644292UActive Publication Date: 2025-03-21JIANGXI RUIMEI COSMETICS PACKAGING MATERIAL CO LTD
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Patent Information

Application Number
CN202420681978.8
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-04-03
Publication Date
2025-03-21
Estimated Expiration
2034-04-03

AI Technical Summary

Technical Problem

The existing positioning tooling for gold-stitching of packaging bottles cannot adjust the position of the packaging bottles and is inflexible to use.

Method used

A positioning tool including a workbench, support legs, lifting columns, hydraulic cylinders and motor-driven positioning tool is designed to adjust the height, left and right, front and rear of the packaging bottle through a sliding and rotating structure.

Benefits of technology

It realizes flexible adjustment of the height, left and right and front and rear positions of the fixed packaging bottle, which improves the flexibility and convenience of use.

✦ Generated by Eureka AI based on patent content.

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    Figure CN222644292U_ABST
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Abstract

The utility model belongs to the technical field of positioning tools, and particularly relates to a packaging bottle gold stamping positioning tool which comprises a workbench, supporting legs are arranged at the four corners of the lower end of the workbench correspondingly, lifting columns are slidably installed in the multiple supporting legs correspondingly, and the multiple lifting columns are fixedly connected with the bottom of the workbench; a movable plate is installed at the upper end of the workbench in a sliding mode, a transverse plate is installed at the upper end of the movable plate in a sliding mode, vertical plates are installed on the left side and the right side of the upper end of the transverse plate in a sliding mode, and hydraulic cylinders are installed on the sides, close to each other, of the two vertical plates in a rotating mode. A second translation screw rod is rotated through a second rocking wheel to enable a second translation plate to slide back and forth on a second sliding rod, a transverse plate moves back and forth to achieve back and forth movement adjustment of the packaging bottle, and the device can adjust different positions of the packaging bottle and is flexible to use.
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Description

Technical Field

[0001] The utility model relates to a positioning tool, in particular to a positioning tool for hot stamping of packaging bottles. Background Art

[0002] After the production and processing of cosmetics are completed, they need to be packaged in bottles for the final packaging. In order to make it convenient for users to use and for aesthetics, cosmetics are generally packaged in different appearances.

[0003] In order to make the surface of the packaging bottle more beautiful, patterns or texts will be printed on the surface of the packaging bottle. Most of the cosmetic packaging bottles are printed with gold stamping. The metal printing plate is heated and foil is placed on the printed matter to emboss golden text or patterns. The packaging bottle needs to be fixed before or during the gold stamping process, so a positioning tool for gold stamping of packaging bottles is needed.

[0004] The existing positioning tooling for hot stamping of packaging bottles uses a cylinder to fix the top and bottom of the packaging bottle to achieve positioning, but the position of the packaging bottle cannot be adjusted after positioning, and cannot be adjusted and used according to the position of the hot stamping device, and is less flexible to use. Utility Model Content

[0005] The main purpose of the present invention is to provide a positioning tool for hot stamping of packaging bottles, so as to effectively solve the problems raised by the inventor in the above background technology.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0007] A positioning tool for hot stamping of packaging bottles comprises a workbench, wherein supporting legs are arranged at the four corners of the lower end of the workbench, lifting columns are slidably installed in a plurality of the supporting legs, a plurality of the lifting columns are fixedly connected to the bottom of the workbench, a base is fixedly installed at the lower ends of a plurality of the supporting legs, a movable plate is slidably installed at the upper end of the workbench, a horizontal plate is slidably installed at the upper end of the movable plate, vertical plates are slidably installed on the left and right sides of the upper end of the horizontal plate, a hydraulic cylinder is rotatably installed on one side of two vertical plates close to each other, and fixed plates are fixedly installed on the output ends of two hydraulic cylinders.

[0008] Preferably, lifting screws are rotatably installed in several of the support legs, the lifting column is threadedly installed on the lifting screw, a slide rail is fixedly installed on the inner wall of the support leg, a slider is fixedly installed on the lower end of the lifting column, the slider is slidably connected to the slide rail, a transmission rod is rotatably installed between the two front support legs and in front of the two rear support legs, a first bevel gear is fixedly installed on the rotating shaft at the lower end of several of the lifting screws, a second bevel gear is fixedly installed at both ends of the two transmission rods, the second bevel gear is meshed with the first bevel gear, a telescopic rod is fixedly installed in the middle of the lower end of the workbench, a U-shaped fixing block is fixedly installed on the telescopic end of the telescopic rod, and a double-axis motor is fixedly installed on the inner side of the lower end of the U-shaped fixing block , rotating rods are fixedly installed at the output ends of both ends of the double-axis motor, and the other ends of the two rotating rods are fixedly installed with third bevel gears, and the middle parts of the two transmission rods are fixedly installed with fourth bevel gears, and the third bevel gears are meshed with the fourth bevel gears. The double-axis motor drives the two rotating rods and the two third bevel gears to rotate, thereby driving the two fourth bevel gears to rotate and the two transmission rods to rotate, and at the same time, the four second bevel gears rotate to drive the four first bevel gears to rotate, thereby driving the four lifting screws to rotate and the four lifting columns to rise and fall at the same time, and the slider will slide in the slide rail and the telescopic rod will be telescoped to make the lifting column rise and fall smoothly, so that the lifting column drives the workbench to rise and fall, so that the height of the fixed packaging bottle can be adjusted for use.

[0009] Preferably, a translation screw is rotatably installed between the left and right inner walls of the workbench, and a sliding rod is fixedly installed, a translation plate is threadedly installed on the translation screw, and the translation plate is slidably connected to the sliding rod, the movable plate is fixedly installed on the upper end of the translation plate, and a rocker wheel is rotatably installed on the right side of the workbench, and the rocker wheel is fixedly connected to the rotating shaft of the translation screw. The translation screw is rotated by the rocker wheel to make the translation plate slide left and right on the sliding rod, thereby driving the movable plate to move left and right to achieve the goal of moving the fixed packaging bottle left and right for adjustment.

[0010] Preferably, a second translation screw is rotatably installed between the front and rear inner walls of the movable plate, and a second slide bar is fixedly installed, the second translation screw is threadedly installed on the second translation screw, and the second translation plate is slidably connected to the second slide bar, the cross plate is fixedly installed on the upper end of the second translation plate, and a second rocker wheel is rotatably installed on the front side of the movable plate, and the second rocker wheel is fixedly connected to the rotating shaft of the second translation screw. The second translation screw is rotated by the second rocker wheel to make the second translation plate slide back and forth on the second slide bar, thereby driving the cross plate to move back and forth to achieve the goal of moving the fixed packaging bottle backward for adjustment and use.

[0011] Preferably, a bidirectional screw rod 1 is rotatably installed between the left and right inner walls of the horizontal plate, and a limit rod 1 is fixedly installed, the two vertical plates are respectively threadedly installed on the threads on both sides of the bidirectional screw rod 1, and the two vertical plates are slidably connected to the limit rod 1, and a rocker wheel 3 is rotatably installed on the right side of the horizontal plate, and the rocker wheel 3 is fixedly connected to the rotating shaft of the bidirectional screw rod 1. The bidirectional screw rod 1 is rotated by the rocker wheel 3 to make the two vertical plates slide toward each other on the limit rod 1, and the two vertical plates are moved toward each other with the two hydraulic cylinders, so that the distance between the two fixed plates can be adjusted, which can be adjusted according to the length of the packaging bottle.

[0012] Preferably, a rotating motor is fixedly installed on the outer side of the vertical plate on the right, and the output end of the rotating motor is fixedly connected to one of the fixed ends of the hydraulic cylinders, and a two-way screw rod is rotatably installed between the upper and lower inner walls of the vertical plate on the left and a limit rod is fixedly installed, and L-shaped fixing blocks are threadedly installed on the threads on both sides of the two-way screw rods, and the two L-shaped fixing blocks are slidably connected to the limit rods, and the ends of the two L-shaped fixing blocks that are close to each other are both arc-shaped, and a servo motor is fixedly installed on the upper end of the vertical plate on the left, and the output end of the servo motor is fixedly connected to the rotating shaft at the upper end of the two-way screw rods. By driving one of the hydraulic cylinders to rotate by the rotating motor, the two hydraulic cylinders can be rotated with the fixed packaging bottles, and the two-way screw rod is driven by the servo motor to make the two L-shaped fixing blocks slide toward each other on the limit rods, and the two L-shaped fixing blocks are moved close to each other to collide with one of the hydraulic cylinders, so that the hydraulic cylinders can be fixed to prevent accidental rotation.

[0013] In view of this, compared with the prior art, the beneficial effects of the utility model are:

[0014] In the present application, a movable plate is set up, and a translation screw rod is rotated by a rocker wheel 1 to make the translation plate 1 slide left and right on the slide rod 1, thereby driving the movable plate to move left and right to achieve the left and right movement and adjustment of the fixed packaging bottle for use. At the same time, a translation screw rod is rotated by a rocker wheel 2 to make the translation plate 2 slide back and forth on the slide rod 2, thereby driving the cross plate to move back and forth to achieve the front and back movement and adjustment of the fixed packaging bottle for use. The fixed packaging bottle can be adjusted to different positions for use, which is more flexible and convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a front view cross-sectional view of the positioning tool for hot stamping of packaging bottles provided by the utility model;

[0016] Figure 2 The figure shows a side cross-sectional view of the positioning tool for hot stamping of packaging bottles provided by the utility model;

[0017] Figure 3 The figure shows a top view of the supporting legs of the positioning tooling for hot stamping of packaging bottles provided by the utility model.

[0018] Icons: 1. Workbench; 2. Support legs; 3. Base; 4. Lifting screw; 5. Lifting column; 6. First bevel gear; 7. Transmission rod; 8. Second bevel gear; 9. Slide rail; 10. Slider; 11. Telescopic rod; 12. U-shaped fixing block; 13. Dual-axis motor; 14. Rotating rod; 15. Third bevel gear; 16. Fourth bevel gear; 17. Translation screw 1; 18. Sliding rod 1; 19. Translation plate 1 ; 20. Rocker wheel one; 21. Moving plate; 22. Translation screw rod two; 23. Slide rod two; 24. Translation plate two; 25. Rocker wheel two; 26. Horizontal plate; 27. Bidirectional screw rod one; 28. Limit rod one; 29. ​​Rocker wheel three; 30. Vertical plate; 31. Hydraulic cylinder; 32. Fixed plate; 33. Rotating motor; 34. Bidirectional screw rod two; 35. Limit rod two; 36. L-shaped fixing block; 37. Servo motor. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0020] See also Figure 1-3 , the utility model provides the following embodiments:

[0021] A positioning tool for hot stamping of packaging bottles comprises a workbench 1, wherein support legs 2 are arranged at the four corners of the lower end of the workbench 1, lifting columns 5 are slidably installed in a plurality of the support legs 2, and a plurality of the lifting columns 5 are fixedly connected to the bottom of the workbench 1, a base 3 is fixedly installed at the lower ends of a plurality of the support legs 2, a moving plate 21 is slidably installed at the upper end of the workbench 1, a horizontal plate 26 is slidably installed at the upper end of the moving plate 21, vertical plates 30 are slidably installed on the left and right sides of the upper end of the horizontal plate 26, a hydraulic cylinder 31 is rotatably installed on one side of the two vertical plates 30 close to each other, and a fixed plate 32 is fixedly installed at the output ends of the two hydraulic cylinders 31.

[0022] Specifically, a plurality of support legs 2 are rotatably installed with lifting screws 4, a lifting column 5 is threadedly installed on the lifting screw 4, a slide rail 9 is fixedly installed on the inner wall of the support leg 2, a slider 10 is fixedly installed on the lower end of the lifting column 5, the slider 10 is slidably connected to the slide rail 9, a transmission rod 7 is rotatably installed between the two front support legs 2 and between the two rear support legs 2, a first bevel gear 6 is fixedly installed on the rotating shaft at the lower end of a plurality of lifting screws 4, a second bevel gear 8 is fixedly installed at both ends of the two transmission rods 7, and the second bevel gear 8 is meshed with the first bevel gear 6, a telescopic rod 11 is fixedly installed in the middle of the lower end of the workbench 1, a U-shaped fixed block 12 is fixedly installed on the telescopic end of the telescopic rod 11, a double-axis motor 13 is fixedly installed on the inner side of the lower end of the U-shaped fixed block 12, and outputs at both ends of the double-axis motor 13 A rotating rod 14 is fixedly installed at each end, and a third bevel gear 15 is fixedly installed at the other end of the two rotating rods 14. A fourth bevel gear 16 is fixedly installed at the middle part of the two transmission rods 7. The third bevel gear 15 is meshed with the fourth bevel gear 16. The two rotating rods 14 and the two third bevel gears 15 are driven to rotate by the dual-axis motor 13, thereby driving the two fourth bevel gears 16 to rotate and the two transmission rods 7 to rotate. At the same time, the four second bevel gears 8 are rotated to drive the four first bevel gears 6 to rotate, thereby driving the four lifting screws 4 to rotate and the four lifting columns 5 to lift and lower at the same time. At the same time, the slider 10 will slide in the slide rail 9 and the telescopic rod 11 will be telescoped to make the lifting column 5 lift and lower smoothly, so that the lifting column 5 drives the workbench 1 to lift and lower, so that the height of the fixed packaging bottle can be adjusted for use.

[0023] Specifically, a translation screw rod 17 is rotatably installed between the left and right inner walls of the workbench 1, and a slide rod 18 is fixedly installed. A translation plate 19 is threadedly installed on the translation screw 17, and the translation plate 19 is slidably connected to the slide rod 18. A moving plate 21 is fixedly installed on the upper end of the translation plate 19. A rocker wheel 20 is rotatably installed on the right side of the workbench 1, and the rocker wheel 20 is fixedly connected to the rotating shaft of the translation screw 17. The translation screw 17 is rotated by the rocker wheel 20 to make the translation plate 19 slide left and right on the slide rod 18, thereby driving the moving plate 21 to move left and right to achieve moving the fixed packaging bottle left and right for adjustment.

[0024] Specifically, a translation screw rod 22 is rotatably installed between the front and rear inner walls of the movable plate 21, and a slide rod 23 is fixedly installed. A translation plate 24 is threadedly installed on the translation screw rod 22, and the translation plate 24 is slidably connected to the slide rod 23. A cross plate 26 is fixedly installed on the upper end of the translation plate 24. A rocker wheel 25 is rotatably installed on the front side of the movable plate 21. The rocker wheel 25 is fixedly connected to the rotating shaft of the translation screw 22. The translation screw 22 is rotated by the rocker wheel 25 to make the translation plate 24 slide back and forth on the slide rod 23, thereby driving the cross plate 26 to move back and forth to achieve the purpose of moving the fixed packaging bottle backward for adjustment.

[0025] Specifically, a bidirectional screw 27 is rotatably installed between the left and right inner walls of the horizontal plate 26, and a limiting rod 28 is fixedly installed. Two vertical plates 30 are respectively threadedly installed on the threads on both sides of the bidirectional screw 27, and the two vertical plates 30 are slidably connected with the limiting rod 28. A rocker wheel 29 is rotatably installed on the right side of the horizontal plate 26, and the rocker wheel 29 is fixedly connected to the rotating shaft of the bidirectional screw 27. The bidirectional screw 27 is rotated by the rocker wheel 29 to make the two vertical plates 30 slide toward each other on the limiting rod 28, and the two vertical plates 30 are moved toward each other with the two hydraulic cylinders 31, so that the distance between the two fixed plates 32 can be adjusted, which can be adjusted according to the length of the packaging bottle.

[0026] Specifically, a rotating motor 33 is fixedly installed on the outer side of the right vertical plate 30, and the output end of the rotating motor 33 is fixedly connected to the fixed end of one of the hydraulic cylinders 31. A two-way screw rod 34 is rotatably installed between the upper and lower inner walls of the left vertical plate 30 and a limiting rod 35 is fixedly installed. L-shaped fixing blocks 36 are threadedly installed on the threads on both sides of the two-way screw rod 34. The two L-shaped fixing blocks 36 are slidably connected to the limiting rod 35, and the ends of the two L-shaped fixing blocks 36 that are close to each other are both arc-shaped. A servo motor 37 is fixedly installed on the upper end of the left vertical plate 30, and the output end of the servo motor 37 is fixedly connected to the rotating shaft at the upper end of the two-way screw rod 34. By driving one of the hydraulic cylinders 31 to rotate through the rotating motor 33, the two hydraulic cylinders 31 can be rotated with the fixed packaging bottles. The two-way screw rod 34 is driven by the servo motor 37 to make the two L-shaped fixing blocks 36 slide toward each other on the limiting rod 35. The two L-shaped fixing blocks 36 are moved close to each other and collide with one of the hydraulic cylinders 31, so that the hydraulic cylinder 31 can be fixed to prevent accidental rotation.

[0027] The working principle of the utility model is as follows: the device is supported by the supporting legs 2 and the base 3, and according to the length of the packaging bottle that needs to be stamped, the two-way screw rod 27 is rotated by the rocker 3 29 to make the two vertical plates 30 slide toward each other on the limit rod 28, so as to adjust the distance between the two hydraulic cylinders 31. After adjusting to the appropriate position, the packaging bottle that needs to be stamped is fixedly positioned between the two fixed plates 32 by the two hydraulic cylinders 31 for stamping, and the two rotating rods 14 and the two third bevel gears 15 are driven to rotate by the double-axis motor 13, thereby driving the two fourth bevel gears 16 to rotate and the two transmission rods 7 to rotate, and at the same time, the four second bevel gears 8 are rotated to drive the four first bevel gears 6 to rotate, thereby driving the four lifting screws 4 to rotate and make the four lifting columns 5 rise and fall at the same time, and at the same time, the slider 10 will slide in the slide rail 9 and the telescopic rod 11 will be telescoped to make the lifting column 5 rise and fall smoothly. The lifting of the lifting column 5 will drive the workbench 1 to lift and lower to adjust the height of the fixed packaging bottle. The translation screw 17 is rotated by the rocker 20 to make the translation plate 19 slide left and right on the slide bar 18, thereby driving the moving plate 21 to move left and right to achieve the left and right movement adjustment of the fixed packaging bottle. At the same time, the translation screw 22 is rotated by the rocker 25 to make the translation plate 24 slide back and forth on the slide bar 23, thereby driving the cross plate 26 to move back and forth to achieve the forward and backward movement adjustment of the fixed packaging bottle. At the same time, the hydraulic cylinder 31 is driven to rotate by the rotating motor 33 to rotate the fixed packaging bottle. After the rotation adjustment is completed, the two-way screw 2 34 is driven by the servo motor 37 to make the two L-shaped fixing blocks 36 slide close to each other on the limit rod 2 35, and the L-shaped fixing block 36 is made to contact with one of the hydraulic cylinders 31 to complete the fixation to prevent accidental rotation during use.

[0028] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0029] The preferred embodiments of the utility model disclosed above are only used to help explain the utility model. The preferred embodiments do not describe all the details in detail, nor do they limit the utility model to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the utility model, so that technicians in the relevant technical field can well understand and use the utility model. The utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A positioning tool for hot stamping of packaging bottles, comprising a workbench (1), characterized in that: Support legs (2) are provided at four corner positions of the lower end of the workbench (1), and lifting columns (5) are slidably installed in a plurality of the support legs (2), and a plurality of the lifting columns (5) are fixedly connected to the bottom of the workbench (1); a base (3) is fixedly installed at the lower ends of a plurality of the support legs (2); a movable plate (21) is slidably installed at the upper end of the workbench (1), a horizontal plate (26) is slidably installed at the upper end of the movable plate (21), and vertical plates (30) are slidably installed on both sides of the upper end of the horizontal plate (26); a hydraulic cylinder (31) is rotatably installed on one side of the two vertical plates (30) close to each other, and a fixed plate (32) is fixedly installed at the output ends of the two hydraulic cylinders (31).

2. A positioning tool for hot stamping of packaging bottles according to claim 1, characterized in that: A lifting screw (4) is rotatably installed in a plurality of the supporting legs (2), the lifting column (5) is threadedly installed on the lifting screw (4), a slide rail (9) is fixedly installed on the inner wall of the supporting leg (2), a slider (10) is fixedly installed at the lower end of the lifting column (5), and the slider (10) is slidably connected to the slide rail (9), a transmission rod (7) is rotatably installed between the two front supporting legs (2) and between the two rear supporting legs (2), a first bevel gear (6) is fixedly installed on the rotating shaft at the lower end of a plurality of the lifting screws (4), a second bevel gear (8) is fixedly installed at both ends of the two transmission rods (7), and the second The bevel gear (8) is meshed with the first bevel gear (6); a telescopic rod (11) is fixedly installed in the middle of the lower end of the workbench (1); a U-shaped fixed block (12) is fixedly installed at the telescopic end of the telescopic rod (11); a double-axis motor (13) is fixedly installed on the inner side of the lower end of the U-shaped fixed block (12); a rotating rod (14) is fixedly installed at both output ends of the double-axis motor (13); a third bevel gear (15) is fixedly installed at the other ends of the two rotating rods (14); a fourth bevel gear (16) is fixedly installed in the middle of the two transmission rods (7); and the third bevel gear (15) is meshed with the fourth bevel gear (16).

3. The positioning tool for hot stamping of packaging bottles according to claim 1, characterized in that: A translation screw rod (17) is rotatably mounted between the left and right inner walls of the workbench (1), and a slide rod (18) is fixedly mounted thereon; a translation plate (19) is threadedly mounted on the translation screw rod (17), and the translation plate (19) is slidably connected to the slide rod (18); the moving plate (21) is fixedly mounted on the upper end of the translation plate (19); a rocker wheel (20) is rotatably mounted on the right side of the workbench (1), and the rocker wheel (20) is fixedly connected to the rotating shaft of the translation screw rod (17).

4. The positioning tool for hot stamping of packaging bottles according to claim 1, characterized in that: A second translation screw rod (22) is rotatably mounted between the front and rear inner walls of the movable plate (21), and a second slide rod (23) is fixedly mounted thereon; a second translation plate (24) is threadedly mounted on the second translation screw rod (22), and the second translation plate (24) is slidably connected to the second slide rod (23); the cross plate (26) is fixedly mounted on the upper end of the second translation plate (24); a second rocking wheel (25) is rotatably mounted on the front side of the movable plate (21), and the second rocking wheel (25) is fixedly connected to the rotating shaft of the second translation screw rod (22).

5. The positioning tool for hot stamping of packaging bottles according to claim 1, characterized in that: A bidirectional screw rod (27) is rotatably mounted between the left and right inner walls of the horizontal plate (26), and a limiting rod (28) is fixedly mounted thereon; the two vertical plates (30) are respectively threadedly mounted on the threads on both sides of the bidirectional screw rod (27), and the two vertical plates (30) are both slidably connected to the limiting rod (28); a rocking wheel (29) is rotatably mounted on the right side of the horizontal plate (26), and the rocking wheel (29) is fixedly connected to the rotating shaft of the bidirectional screw rod (27).

6. The positioning tool for hot stamping of packaging bottles according to claim 1, characterized in that: A rotating motor (33) is fixedly installed on the outer side of the right vertical plate (30), and the output end of the rotating motor (33) is fixedly connected to the fixed end of one of the hydraulic cylinders (31). A bidirectional screw rod (34) is rotatably installed between the upper and lower inner walls of the left vertical plate (30) and a limiting rod (35) is fixedly installed. L-shaped fixing blocks (36) are threadedly installed on the threads on both sides of the bidirectional screw rod (34). Both L-shaped fixing blocks (36) are slidably connected to the limiting rod (35), and the ends of the two L-shaped fixing blocks (36) that are close to each other are both arc-shaped. A servo motor (37) is fixedly installed on the upper end of the left vertical plate (30), and the output end of the servo motor (37) is fixedly connected to the upper end rotation shaft of the bidirectional screw rod (34).