JP2005227596A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer which automatically recognizes the kind of a heater roller newly replaced and automatically selects the predetermined optimum temperature control for the heater roller to prevent the damages to the printing paper and the heater roller caused by missing of control changes and also to provide optimum fixing conditions. <P>SOLUTION: This printer uses a photo detector when starting to print to detect the light of the fixing lamp provided inside a heater roller through a hole in the non-fixing area of the heater roller, and automatically recognizes the kind of the heater roller from the cycle of the detected light, then selects the temperature optimum to the heater roller to start printing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a printing apparatus for fixing paper using a heating roll and a pressure roll.

  As a fixing device of a printing apparatus typified by a laser printer or a copying machine, a recording material holding a toner image is heated and pressed while being nipped and conveyed between a heating roll and a pressure roll to fix the toner image on the recording material. A fixing device having the above-described configuration is known. A plurality of fixing lamps serving as a heat source are provided inside the heating roll. In recent years, printing devices are required to print on various types of paper with high printing speed, high image quality, and fixing devices require rapid heat supply for fixing toner images when high-speed printing is required. One type of heating roll with a hard and thin surface layer for the purpose of achieving high quality, and a thick and soft heating roll with the purpose of minimizing crushing when fixing a toner image when high image quality is required This heating roll is difficult to handle. Therefore, in order to meet the demands required by one printing apparatus, it is necessary to change to a heating roll that meets the demands. However, since the heat transfer rate, heat transfer speed, and heat-resistant temperature differ depending on the type of heating roll, it is necessary to change the temperature control each time the heating roll is changed in order to obtain the amount of heat necessary for optimal toner image fixing. In addition, since the temperature control was not changed at the same time when the heating roll was changed, there was a possibility that excessive toner fixing heat amount and excessive supply would occur, resulting in fixing failure and damage to the printing paper and heating roll.

JP 09-106208 A

  The object of the present invention is to automatically recognize the type of the heating roll when the heating roll is changed in accordance with the printing purpose, and automatically select and execute the heating roll temperature control suitable for the heating roll. Therefore, it is possible to prevent damage to the printing paper and the heating roll due to forgetting to change the control, and to achieve optimum fixing conditions.

  The above object includes a heating roll provided with a fixing lamp inside, and a pressure roll provided so as to be capable of being pressed against the heating roll, and a recording material holding a toner image is placed between the heating roll and the pressure roll. In a fixing device that sandwiches and conveys the toner image on a recording material while being heated and pressurized at a pressure contact portion, the light receiving element receives light emitted from the fixing lamp from a hole provided in a non-fixing area of the heating roll. This can be achieved by automatically recognizing the type of the heating roll by detecting the light receiving period.

  According to the present invention, when the heating roll is changed, the printing apparatus automatically recognizes the type of the heating roll, automatically selects and executes the optimum temperature control for the preset heating roll, This prevents damage to the printing paper and heating roll due to forgetting to change the control, and provides optimal fixing conditions.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, a laser beam printer using an electrophotographic system will be exemplified as a printing apparatus to which the present invention is applied, and the overall configuration will be described with reference to FIG.

  In FIG. 2, reference numeral 1 denotes a laser beam printer. The photosensitive drum 21 starts to rotate in the direction of the arrow based on a printing operation start signal from the controller 22. The photosensitive drum 21 rotates at a speed corresponding to the printing speed of the laser beam printer 1 and continues to rotate until the printing operation is completed. When the photosensitive drum 21 starts to rotate, a high voltage is applied to the corona charger 2 and, for example, positive charges are uniformly charged on the surface of the photosensitive drum 21.

  The rotary polygon mirror 3 starts rotating as soon as the laser beam printer 1 is turned on, and maintains constant speed rotation with high accuracy while the power is turned on. Light output from the light source 4 such as a semiconductor laser is reflected by the rotary polygon mirror 3 and irradiated while scanning the photosensitive drum 21 through the fθ lens 5.

  When character data or graphic data converted into a dot image is sent from the controller 22 to the laser beam printer 1 as a laser beam on / off signal, the surface of the photosensitive drum 21 is irradiated with the laser beam and the non-irradiated portion. Are formed, and a so-called electrostatic latent image is formed. When the photosensitive drum area holding the electrostatic latent image reaches a position facing the developing device 6, toner is supplied to the electrostatic latent image, and the portion of the photosensitive drum 21 on which the electric charge has disappeared due to the laser beam irradiation, For example, a positively charged toner is attracted by static electricity and a toner image is formed on the photosensitive drum 21.

  The continuous sheet 7 stored in the sheet hopper 11 is synchronized with the timing at which the toner image of the print data formed on the photosensitive drum 21 reaches the transfer position by the sheet conveying tractor 8 and the transfer unit. 10 is conveyed toward the middle.

  The toner image formed on the photosensitive drum 21 is sucked onto the sheet 7 by the action of the transfer unit 10 that applies a charge having a polarity opposite to that of the toner image to the back side of the sheet 7.

  In this way, the sheet 7 set in the sheet hopper 11 is conveyed to the fixing device 12 through the sheet conveying tractor 8, the transfer device 10, the sheet conveying tractor 9 and the buffer plate 24. The sheet 7 that has reached the fixing device 12 is preheated by the preheater 13 and then heated and pressed by a nip portion formed by a pair of fixing rolls including a heating roll 14 having a fixing lamp 25 and a pressure roll 15. The toner image is melted and fixed on the paper 7 while being nipped and conveyed.

  The paper 7 sent out by the heating roll 14 and the pressure roll 15 is sent out to the stacker table 19 side by the paper feed roll 16 and is alternately folded along the perforation by the swing operation of the swing fin 17. Further, while the folded state is adjusted by the rotating paddle 18, they are stacked on the stacker table 19. The area that has passed the transfer position of the photosensitive drum 21 is cleaned by the cleaning device 20 and is prepared for the next printing operation.

In FIG. 2, reference numeral 23 denotes a display screen for displaying information based on the state of the laser beam printer 1 during the printing operation. The buffer plate 24 is for absorbing slack or tension generated on the paper 7 when a paper transport speed difference occurs between the paper transport tractor 9 and the fixing rolls 14 and 15. Reference numeral 26 denotes a web member provided so as to be able to come into contact with the surface of the heating roll 14 and to be wound up, and for cleaning the surface of the heating roll 14 and applying a release agent to the surface of the heating roll 14. Is.
Next, the detailed structure of a heating roll is demonstrated using FIG.

  At the time of starting the printing apparatus, the fixing lamp emits light continuously for a certain period until the type of the heating roll is detected, and the light emission leaks from the hole 27 of about φ5 opened in the non-fixing area 14B of the heating roll. . The light receiving element 28 is installed at a position facing the hole 27 formed in the end portion 14 of the heating roll and at a distance from the heating roll. The light emission of the fixing lamp is detected by the light receiving element 28, the type of the heating roll is recognized from the light receiving period 29, and a preset temperature control suitable for the heating roll is selected and executed. Note that the number of holes 27 provided in the heating roll 14 varies depending on the type of the heating roll, thereby generating a plurality of light emission periods unique to the heating roll.

  When using multiple types of heating rolls with a single printing device, automatically recognize the types of heating rolls and automatically select and execute the optimal temperature control for each heating roll. As a result, the optimum fixing conditions can be provided to the printing apparatus without changing the temperature control by the operator.

The block diagram of this invention. 1 is an overall configuration diagram of a printing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 14 ... Heating roll, 14A ... Fixing area | region, 14B ... Non-fixing area | region, 27 ... Hole provided in the non-fixing area | region of a heating roll, 28 ... Light receiving element, 29 ... Light receiving period.

Claims (3)

  A heating roll provided with a fixing lamp inside, and a pressure roll provided so as to be capable of being pressed against the heating roll, and a recording material holding a toner image is heated at a pressure contact portion between the heating roll and the pressure roll. In a fixing device for nipping and conveying while pressing and fixing the toner image on a recording material, a hole is formed in a non-fixing area of the heating roll, and light emission of the fixing lamp provided in the heating roll is detected by a light receiving element. A printing apparatus in which the printing apparatus automatically recognizes the type of the heating roll according to the cycle.   2. The temperature control of the heating roll automatically set by the printing apparatus for each type is automatically selected according to the type of the heating roll after the printing apparatus recognizes the type of the heating roll. The printing apparatus as described. 2. The type of the heating roll is recognized by causing the fixing lamp to continuously emit light for a certain period from when the printing apparatus is started until the printing apparatus recognizes the type of the heating roll. The printing apparatus as described.

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