Method and device for controlling temperature uniformity of heating roller

[0013] Embodiment one

[0014] attached figure 1 An embodiment of the present invention is given, and it can be seen from the accompanying drawings that the present invention relates to a method for controlling the temperature uniformity of a heating roller. The heating roller is heated by an electromagnetic heating method, and the heating roller is a hollow roller with a hollow center. The heating device is arranged in the hollow part of the heating roller; the electromagnetic heating device is more than three electromagnetic heating coils, and the temperature uniformity of the heating roller is controlled by controlling the calorific value of the electromagnetic heating coils respectively. Said controlling the temperature uniformity of the heating roller by respectively controlling the heat generation of the electromagnetic heating coil is to arrange the electromagnetic heating coil in the hollow part of the heating roller along the axial direction of the heating roller, and according to the heat dissipation of the heating roller, each electromagnetic heating coil For different heating power; for the part of the heating roller with faster heat dissipation, the electromagnetic heating coil with higher heating power is used, and for the part of the heating roller with slower heat dissipation, the electromagnetic heating coil with smaller heating power is used to ensure the heat dissipation and absorption of the heating roller. The heat rate is the same, so that the temperature of the whole heating roller can be evenly raised and lowered.

[0015] A control device for temperature uniformity of a heating roller proposed according to the above method is: a control device for temperature uniformity of a heating roller, comprising a heating roller 2, a heating roller supporting device 3 and a heating device 1; the heating roller 2 is installed on the heating On the roller supporting device 3, the heating roller 2 is a hollow heating roller whose middle part is hollow, and a heating device 1 is installed in the hollow part of the heating roller 2, and the heating device 1 is an electromagnetic heating device; the electromagnetic heating device 1 is 8 The electromagnetic heating rings are arranged in even numbers, respectively the first electromagnetic heating ring 3, the second electromagnetic heating ring 4, the third electromagnetic heating ring 5, the fourth electromagnetic heating ring 6, the fifth electromagnetic heating ring 7, the sixth electromagnetic heating ring 8, The seventh electromagnetic heating ring 9 and the eighth electromagnetic heating ring, the first electromagnetic heating ring 3, the second electromagnetic heating ring 4, the third electromagnetic heating ring 5, the fourth electromagnetic heating ring 6, the fifth electromagnetic heating ring 7, the sixth electromagnetic heating ring The electromagnetic heating ring 8, the seventh electromagnetic heating ring 9 and the eighth electromagnetic heating ring 10 are axially arranged in the hollow part of the heating roller, and each electromagnetic heating ring has a different heating power; the power of the electromagnetic heating ring depends on the heat dissipation of the heating roller. The conditions are adjusted independently; wherein, the two ends 12 and 13 of the heating roller with faster heat dissipation adopt electromagnetic heating coils with higher heating power, and the middle part of the heating roller with slower heat dissipation adopts electromagnetic heating coils with lower heating power. To ensure that the heat dissipation and heat absorption rate of the heating roller are the same, so that the temperature of the entire heating roller can rise and fall evenly. That is, the heating power of the first electromagnetic heating coil 3 and the eighth electromagnetic heating coil 10 is the largest, the heating power of the second electromagnetic heating coil 4 and the seventh electromagnetic heating coil 9 is second, and the third electromagnetic heating coil 5 and the sixth electromagnetic heating coil The heating power of 8 is the third, and the heating power of the fourth electromagnetic heating coil 6 and the fifth electromagnetic heating coil 7 is the smallest. The heating roller 2 is mounted on the heating roller supporting device 3 through a bearing 11 .

[0016] The temperature curve relationship between the heating roller and the electromagnetic heating coil is as attached figure 2 shown. From attached figure 2 It can be seen that the temperature distribution curve of the heating roller due to heat dissipation is shown in curve 14, and the temperature at both ends is low due to fast heat dissipation; so the heat provided by the electromagnetic heating coil is shown in curve 15 according to the heat dissipation of the heating roller . If the heat loss at both ends is large, it can be compensated by increasing the power of the electromagnetic heating coil to ensure the balance of residual heat, thereby ensuring the temperature uniformity of the heating roller.

[0017] The number of electromagnetic heating rings can also be 4, 6 or 10 and other even numbers of electromagnetic heating rings, which are uniformly distributed in the central hollow part of the heating roller 2 in the axial direction. The electromagnetic heating coil is fixed on the heating roller supporting device 3 and does not rotate with the heating roller.

[0018] Embodiment two

[0019] The principle of the second embodiment is the same as that of the first embodiment, except that the electromagnetic heating coils are arranged in odd numbers, such as 3, 5, 7, 9 and other odd numbers of electromagnetic heating coils. The electromagnetic heating coil is fixed in the heating roller 2 and rotates with the heating roller.