Cooling structure for center large roller of flexible plate printing machine

Abstract

The utility model discloses a flexible plate printing machine center large roller cooling structure which comprises an outer roller shaft, a cooling cavity is formed in the outer roller shaft, a framework layer is arranged in the center of the cooling cavity, an outer shaft sleeve is arranged in the framework layer, a spiral left flow channel is formed in the surface of the outer shaft sleeve in the clockwise direction, and a spiral right flow channel is formed in the surface of the outer shaft sleeve in the clockwise direction. The two ends of the spiral left flow channel are connected through a first connecting pipe, a first industrial pump is arranged on the first connecting pipe, an inner shaft sleeve is arranged in the outer shaft sleeve, a spiral right flow channel is formed in the outer wall of the inner shaft sleeve anticlockwise, and the two ends of the spiral right flow channel communicate through a second connecting pipe. And the second connecting pipe is connected with a second industrial pump. The roller is scientific and reasonable in structural design, the left flow channel and the right flow channel form two-way convection, the flow speed of cooling liquid is increased, the surface temperature difference of the roller body is small, and the problem of uneven cooling is solved; the included angle between the axis of the double-flow channel and the axis of the roller body is 15 degrees, and the turbulence effect is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of printing press equipment technology, specifically a cooling structure for the central large roller of a flexographic printing press. Background Technology

[0002] Flexographic printing presses use highly fluid inks. The ink is transferred to the image areas of the printing plate via ink fountain rollers and anilox rollers, where it is inked. Then, printing pressure is applied by the pressure cylinders to transfer the ink from the printing plate to the substrate. Finally, printing is completed via a drying process. Existing flexographic printing presses have the following drawbacks in their central roller cooling structure:

[0003] Uneven cooling: Traditional single-channel coolant flow paths result in significant temperature differences between the two ends of the roller, causing paper deformation or uneven ink drying. When the temperature difference on the roller surface exceeds ±5℃, the print quality rate decreases. To address this, we propose a central large roller cooling structure for flexographic printing presses. Utility Model Content

[0004] The purpose of this invention is to provide a cooling structure for the central large roller of a flexographic printing press to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a cooling structure for the central large roller of a flexographic printing press, comprising an outer roller shaft, a cooling cavity inside the outer roller shaft, a skeleton layer at the center of the cooling cavity, an outer bushing inside the skeleton layer, a spiral left flow channel on the surface of the outer bushing arranged clockwise, the two ends of the spiral left flow channel being connected by a first connecting pipe, a first industrial pump being installed on the first connecting pipe, an inner bushing being installed inside the outer bushing, a spiral right flow channel on the outer wall of the inner bushing arranged counterclockwise, the two ends of the spiral right flow channel being connected by a second connecting pipe, a second industrial pump being connected to the second connecting pipe, an inner connecting shaft being installed inside the inner bushing, a copper sleeve being installed at the end of the inner connecting shaft, an end cap being installed at the end of the copper sleeve, and solenoid valves being installed on both the first and second connecting pipes.

[0006] In the above scheme, the axes of the left and right spiral channels are at a 15° angle to the axis of the roller body.

[0007] In the above scheme, a temperature sensor is installed inside the outer roller shaft.

[0008] In the above scheme, the copper sleeve is a tin-phosphor bronze copper sleeve.

[0009] In the above scheme, the end cap is a honeycomb aluminum alloy end cap, and a support mechanism is provided at the bottom of the end cap.

[0010] In the above scheme, the first industrial pump, the second industrial pump, and the solenoid valve are all connected to the PLC via wires.

[0011] In the above scheme, the outer roller shaft is a stainless steel roller shaft.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: The cooling structure of the central large roller of the flexographic printing press has a simple and reasonable structural design and strong practicality. The left and right flow channels form bidirectional convection, which increases the flow rate of the coolant and reduces the temperature difference on the roller surface, thus solving the problem of uneven cooling. The dual flow channel axis is designed at a 15° angle with the roller axis, which enhances the turbulence effect. The copper sleeve replaces the traditional bearing, which reduces the friction coefficient, increases the withstand speed, and extends the maintenance cycle. The honeycomb end cap reduces the moment of inertia, solving the problem of excessive moment of inertia. Based on real-time data from the temperature sensor, the PLC dynamically adjusts the opening of the solenoid valve and the power of the industrial pump, resulting in low coolant flow fluctuation. This reduces maintenance and operating costs. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model.

[0014] Figure 2 This is a schematic diagram of the internal structure of the outer bushing of this utility model.

[0015] In the figure: 1. Outer roller shaft; 11. Cooling cavity; 12. Skeleton layer; 13. Outer bushing; 14. Spiral left flow channel; 15. First connecting pipe; 16. First industrial pump; 17. Inner bushing; 18. Spiral right flow channel; 19. Second connecting pipe; 2. Second industrial pump; 21. Inner connecting shaft; 22. Copper sleeve; 23. End cap; 24. Temperature sensor; 25. Solenoid valve. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] Please see Figure 1-2This utility model provides a technical solution: a cooling structure for the central large roller of a flexographic printing press, including an outer roller shaft 1, a cooling cavity 11 inside the outer roller shaft 1, a skeleton layer 12 at the center of the cooling cavity 11, an outer bushing 13 inside the skeleton layer 12, a spiral left-hand flow channel 14 clockwise formed on the surface of the outer bushing 13, the two ends of the spiral left-hand flow channel 14 being connected by a first connecting pipe 15, and a first industrial pump 16 being installed on the first connecting pipe 15. The bushing 13 has an inner bushing 17 inside. The outer wall of the inner bushing 17 has a spiral right flow channel 18 opened counterclockwise. The two ends of the spiral right flow channel 18 are connected through a second connecting pipe 19, and a second industrial pump 2 is connected to the second connecting pipe 19. The inner bushing 17 has an inner connecting shaft 21 inside. The end of the inner connecting shaft 21 is provided with a copper sleeve 22, and the end of the copper sleeve 22 is provided with an end cap 23. Solenoid valves 25 are provided on both the first connecting pipe 15 and the second connecting pipe 19.

[0018] In the above scheme, the axes of the left spiral channel 14 and the right spiral channel 18 form a 15° angle with the axis of the roller body. The bidirectional spiral channel design: the spiral directions of the left channel 14 (clockwise) and the right channel 18 (counterclockwise) are opposite, and their axes form a 15° angle with the axis of the roller body. The pressure difference at the inlet of the two channels creates bidirectional convection, increasing the coolant flow rate and significantly enhancing heat exchange efficiency.

[0019] In the above scheme, a temperature sensor 24 is installed inside the outer roller shaft 1.

[0020] In the above scheme, the copper sleeve 22 is a tin-phosphor bronze copper sleeve. The tin-phosphor bronze copper sleeve 22 has an interference fit with the inner connecting shaft 21, and its surface contains a self-lubricating graphite layer, reducing the coefficient of friction, increasing the withstand speed, and improving its lifespan.

[0021] In the above scheme, the end cap 23 is a honeycomb aluminum alloy end cap, and a support mechanism is provided at the bottom of the end cap 23. The hexagonal honeycomb structure reduces the moment of inertia, and the bottom support mechanism is a spring damping structure, which further reduces the vibration amplitude.

[0022] In the above scheme, the first industrial pump 16, the second industrial pump 2, and the solenoid valve 25 are all connected to the PLC via wires. The temperature sensor 24 monitors the surface temperature of the roller in real time, and the PLC automatically adjusts the opening of the solenoid valve 25 and the power of the industrial pumps based on the temperature difference data to achieve a small flow fluctuation rate and ensure cooling stability under high and low speed conditions.

[0023] In the above scheme, the outer roller shaft 1 is a stainless steel roller shaft. It adopts a double-layer stainless steel composite structure, and through the honeycomb support design of the skeleton layer 12, it can both ensure the rigidity of the roller body and reduce the risk of thermal expansion deformation.

[0024] Working principle:

[0025] In this type of flexographic printing press central roller cooling structure, during operation, the coolant is divided into two paths by the external circulation system. After being pressurized by the first industrial pump 16 and the second industrial pump 2 respectively, the flow rate is regulated by the solenoid valve 25, and the coolant is simultaneously injected into the spiral left flow channel 14 (clockwise) of the outer bushing 13 and the spiral right flow channel 18 (counterclockwise) of the inner bushing 17. Because the axes of the two flow channels form a 15° angle with the roller axis, the coolant forms a bidirectional high-speed turbulent flow within the flow channels. This turbulence disrupts the thermal boundary layer, resulting in a uniform temperature distribution on the roller surface. Simultaneously, the temperature sensor 24... The roller surface temperature data is collected in real time and fed back to the PLC controller. The PLC dynamically adjusts the opening degree of the solenoid valve 25 and the output power of the industrial pump according to the preset program. For example, the water pressure is increased in high-speed printing mode to enhance the cooling intensity, and the energy-saving mode is switched when the speed is low and the standby is low. The combination design of the tin-phosphor bronze sleeve 22 and the honeycomb end cap 23 reduces the moment of inertia and reduces friction loss through self-lubrication. With the spring damping support mechanism, the vibration generated by high-speed operation is absorbed, and finally the comprehensive effect of efficient cooling, stable operation and long service life is achieved.

[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A central large roller cooling structure of a flexographic printing press, comprising an outer roller shaft (1), characterized in that: The outer roller shaft (1) is provided with a cooling cavity (11), the center of which is provided with a framework layer (12), the inside of the framework layer (12) is provided with an outer shaft sleeve (13), the surface of the outer shaft sleeve (13) is provided with a spiral left flow channel (14) along the clockwise direction, the two ends of the spiral left flow channel (14) are connected through a first connecting pipe (15), the first connecting pipe (15) is provided with a first industrial pump (16), the inside of the outer shaft sleeve (13) is provided with an inner shaft sleeve (17), the outer wall of the inner shaft sleeve (17) is provided with a spiral right flow channel (18) along the counterclockwise direction, the two ends of the spiral right flow channel (18) are communicated through a second connecting pipe (19), the second connecting pipe (19) is connected with a second industrial pump (2), the inner shaft sleeve (17) is provided with an inner connecting shaft (21), the end of the inner connecting shaft (21) is provided with a copper sleeve (22), the end of the copper sleeve (22) is provided with an end cover (23), the first connecting pipe (15) and the second connecting pipe (19) are both provided with a solenoid valve (25).

2. A central large roller cooling structure of a flexographic printing press according to claim 1, characterized in that: The axis of the spiral left flow channel (14) and the spiral right flow channel (18) and the axis of the roller body form an angle of 15°.

3. A central large roller cooling structure of a flexographic printing press according to claim 1, characterized in that: The inside of the outer roller shaft (1) is mounted with a temperature sensor (24).

4. A central large roller cooling structure of a flexographic printing press according to claim 1, characterized in that: The copper sleeve (22) is a tin phosphor bronze copper sleeve.

5. A central large roller cooling structure of a flexographic printing press according to claim 1, characterized in that: The end cover (23) is a honeycomb-shaped aluminum alloy end cover, and the bottom of the end cover (23) is provided with a supporting mechanism.

6. A central large roller cooling structure of a flexographic printing press according to claim 1, characterized in that: The first industrial pump (16), the second industrial pump (2) and the solenoid valve (25) are connected with the PLC through wires.

7. A central large roller cooling structure of a flexographic printing press according to claim 1, characterized in that: The outer roller shaft (1) is a stainless steel roller shaft.

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