WO2001088631A1

WO2001088631A1 - Printer and method of fixing

Info

Publication number: WO2001088631A1
Application number: PCT/JP2000/003092
Authority: WO
Inventors: Takahiro Kashikawa
Original assignee: Fujitsu Limited
Priority date: 2000-05-15
Filing date: 2000-05-15
Publication date: 2001-11-22
Also published as: JP4517562B2

Abstract

A printer comprises an electronic photograph unit, which uses toner to develop an electrostatic latent image formed on a photosensitive member and transfers it to a sheet of paper, and an optical fixing device that fuses the toner image on the paper using intense radiation to fix the image. A preheating unit using a Peltier unit as a heat medium is arranged in a stage preceding the optical fixing device, and the paper and the passage are preheated by the waste heat from the Peltier unit to improve the performance of the optical fixing device. Cooled air from the Peltier unit is used to cool the optical fixing device and other units.

Description

Technical Field Printing device and fixing method

The present invention relates to a printer apparatus for printing characters, images, and the like on recording paper using an electrophotographic process and a fixing method thereof, and particularly to a printer apparatus for performing preheating in a stage preceding an optical fixing device and a fixing method thereof. Background art

Conventionally, electrophotography methods used in copiers, laser printers, and the like generally apply a uniform electrostatic charge to a photoconductive insulator layer and irradiate a light image onto the insulator layer. As a result, an electrostatic charge is partially removed to form an electrostatic latent image. Next, a fine powder called toner is adhered to the remaining portion of the electrostatic charge to form a toner image in which the latent image is visible (development). The toner image is transferred onto a recording paper and then fixed. Obtain a print.

In general, in order to obtain good fixability in an electrophotographic process, it is important to efficiently melt the toner transferred on the paper in the fixing step and fix the toner on the paper. As a fixing method, a non-contact fixing method using a conventional optical fixing device is known. The fixing is performed by melting the toner itself by absorbing the strong light from the flash lamp into the toner. However, with the optical fixing method, sufficient fixing properties cannot be obtained due to conditions such as the thickness of the paper, the speed at which the paper is conveyed, and the temperature and humidity of the environment. Also, from the viewpoint of energy saving in recent years, it is almost impossible to increase the flash voltage, and in order to avoid a toner fixing failure caused by a shortage of flash energy due to an increase in the speed of the printer, a pre-heating is required. Must be used.

Conventionally, preheating is performed using a heating wire or ceramic heater as a heat medium. However, it is difficult to perform fine temperature control with these heating media. Also, since the response time is long, when the paper jam occurs, the temperature of the pre-heating section suddenly increases. There is a problem that the paper may be ignited.

Also, when an attempt is made to increase the output of the optical fixing device in order to avoid a toner fixing defect, the UV ink, which is often used for form printing, is discolored, which often causes a problem of poor printing. Further, when the output of the fixing unit is increased, the temperature of the optical fixing unit rises, which may cause damage to the optical fixing unit. In addition, there is a problem that abnormal heating of the opposing paper conveyance path occurs. Furthermore, if the optical fixing device, which is the main heat source in the printer, becomes abnormally heated, the temperature inside the printer rises, causing toner photoconductor filming (toner sticking) and toner fusion in the developing device. Etc. are more likely to occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printer device and a fixing method for the same that maintain stable toner fixability by pre-heating and enable fine temperature control in preheating in light fixing when an electrophotographic process is used. Aim to

DISCLOSURE OF THE INVENTION ''

In order to achieve this object, the present invention is configured as follows. The present invention relates to an electrophotographic unit that develops an electrostatic latent image formed on a photoreceptor with toner and then transfers the developed image onto a sheet of paper, and a toner image that is transferred onto a sheet of toner by irradiating strong light. What is claimed is: 1. A printer device comprising: an optical fixing device that is fixed by melting, wherein a preheating unit using a Peltier element as a heating medium is provided at a stage preceding the optical fixing device. Since the present invention uses the Peltier element as the heating medium of the preheat unit, the fixing property of the optical fixing device can be improved by preheating the paper using the waste heat of the Peltier element. In addition, the temperature control of the Peltier element is determined by the value of the current flowing through the Peltier element, and the response time is as fast as 2 ° CZ seconds (25 ° d ”environment). maintain.

Here, the preheating temperature due to the waste heat of the Peltier element is set in the range of 50 ° C to 100 ° C. In addition, the air cooled by the heat absorption of the Peltier device is used. It has a cooling unit to be ordered. The cooling unit is connected to the chamber that is in contact with the heat absorbing surface of And a cooling system that introduces the air into the champer, cools the air, and then passes the air through the optical fixing device. Furthermore, the air cooled by the cooling unit is used for cooling the power supply unit of the device and the control circuit. In this way, the waste heat surface of the Peltier element is placed at the bottom of the paper transport with the paper surface facing and the paper is preheated, and at the same time, a cooling air chamber is arranged on the heat absorption surface of the Peltier element to create cooled air, and the optical fuser By using it for cooling, the damage of the optical fixing device due to abnormal heating can be reliably prevented, and the power supply unit / control circuit can be cooled.

Further, the present invention is characterized in that a preheating unit is provided for preheating the Bertier element of the preheat unit using waste heat generated in the optical fixing device. This residual heat unit includes a chamber arranged on the heat absorbing surface of the Peltier element via a residual heat space, and a residual heat system for introducing external air to the champer through the optical fixing device by suction by the profiling unit to perform residual heat. The preheat unit may further use the waste heat generated from the power unit control-circuit to preheat the Peltier element of the preheat unit. By using the waste heat obtained from the apparatus as the residual heat of the Peltier element and the print medium, the cold junction temperature of the heat absorbing surface of the Peltier element is raised, and the high contact temperature of the waste heat surface is raised, thereby efficiently pre-heating the Peltier element. Can be At the same time, the air taken in from outside is used for the residual heat of the Peltier device after cooling the optical fuser, power supply unit, control circuit, etc. The damage of the optical fixing device is surely prevented. The preheat unit has a structure in which a plurality of rectangular sheet-shaped Peltier elements are arranged on a plate surface.

The present invention also provides a fixing method for a printer device for developing an electrostatic latent image formed on a photoreceptor by an electrophotographic unit with a toner, transferring the electrostatic latent image onto paper, and then fixing the image. The fixing method is characterized in that before the toner is melted by irradiating strong light with an optical fixing device to fix a toner image on paper, preheating is performed using a Peltier element as a heating medium. The pre-heat temperature due to the waste heat of the Peltier element is set in the range of 50 ° C to 100 ° C. The optical fixing device is cooled using air cooled by the heat absorption of the Peltier device. Furthermore, the Peltier device is preheated using waste heat generated by the optical fixing device. Other details are the same as those of the device. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an explanatory diagram of the internal structure of a printer device of the present invention that performs preheating and cooling using a Peltier device;

FIG. 2 is an explanatory view of the photosensitive drum and the developing unit of FIG. 1;

Figure 3 is an illustration showing the pelchenit and cooling mechanism of Figure 1;

FIG. 4 is an illustration of the perforunit of FIG. 3;

Figure 5 is a diagram illustrating the principle of the Belch II device;

FIG. 6 is an explanatory view of the internal structure of the printer device of the present invention for preheating the perchenite;

Fig. 7 is an explanatory drawing of the peltu-unit and the preheating system of Fig. 6;

Figure 8 is an illustration of the preheating chamber of Figure 7;

FIG. 9 is a characteristic diagram of the preheating temperature and the toner fixing rate in the present invention;

FIG. 10 is a characteristic diagram of the optical fixing device temperature with respect to the number of prints in the first embodiment;

FIG. 11 is a characteristic diagram of the optical fixing device temperature with respect to the number of prints in Comparative Examples 1 and 2. FIG. 12 is a comparison of the toner fixing property and the presence or absence of damage of the optical fixing device in Examples 1 to 4 of the present invention. Explanatory diagram shown with 5;

FIG. 13 is a flowchart of temperature control using the perunit of the present invention;

FIG. 1 shows an embodiment of a printer device using an electrophotographic process to which the present invention is applied, taking a line printer as an example. The line printer 10 stores the continuous paper 12 in the hopper 14, and the continuous paper 12 pulled out from the hopper 14 is sent to the stat force 34 through the paper transport path 24. A photosensitive drum 16 is provided in the middle of the paper transport path 24, and a developing unit 18 is provided for the photosensitive drum 16. The photosensitive drum 16 and the developing unit 18 form a main part of the electrophotographic process of the present invention. The photosensitive drum 16 forms an electrostatic latent image on a light-leak insulating layer formed on the drum surface by scanning a light beam such as an LED print head. The developer unit 18 for the image is the developer After the toner image is transferred by the transfer unit 22 onto the continuous paper 1 2 which is fed through the paper transport path 24, the toner image is then transferred to the optical fixing device 28. Print by fixing and fixing.

FIG. 2 shows a detailed structure of the photosensitive drum 16 and the developing unit 18 of FIG. The photosensitive drum .16 is rotated counterclockwise at a constant speed by a motor (not shown). Around the photosensitive drum 16, two pre-chargers 64, 66 are arranged on the upper left side to uniformly charge the surface of the photosensitive drum 16. Subsequently, an LED print head 68 is provided. The LED print head 68 uses an LED array in which a number of LEDs are arranged in the longitudinal direction of the drum, and the printing pattern is exposed by driving the LED array to emit light in accordance with the printing information. An electrostatic latent image is formed on the surface. The electrostatic latent image formed on the photosensitive drum 16 is developed by a toner component of a two-component developer containing a carrier and a toner at a position of the developing unit 18 to form a toner image. On the other hand, continuous paper for printing is sent to the transfer position of the photosensitive drum 16 by the paper transport unit 20. At this transfer position, a transfer charger 22-1 is arranged to face the photosensitive drum 16, and the toner image on the photosensitive drum 16 is transferred onto the paper. The toner image transferred onto the paper is fixed in the optical fixing device 28 shown in FIG. After the transfer of the toner image onto the paper by the transfer charger 2 2-1, there is residual toner remaining on the photosensitive drum 16 without being transferred, and a cleaning brush 58 and a cleaning blade are used to remove the residual toner. 60 is provided to mechanically remove the residual toner on the photosensitive drum 16. Subsequently, a static elimination LED is provided, and static elimination is performed to return the potential on the photosensitive drum 16 to 0 volt.

Referring again to FIG. 1, the optical fixing device 28 has, for example, four flash lamps 30 arranged in the paper transport direction inside the optical fixing device 28, and emits strong light due to the emission horse motion of the flash lamps 30. By absorbing the toner, the toner itself is melted and fixed on paper. In the present invention, a perheating unit 26 is provided in front of the optical fixing unit 28 in the present invention as a preheating unit, and preheating for heating the continuous paper 12 in front of the optical fixing unit 28 is performed. The pellet unit 26 is disposed with the waste heat surface facing the paper transport path 24 side, and the lower side is a heat absorbing surface. A cooling chamber 36 is arranged on the heat absorbing surface side of Pelchenit 26. Cooling champ 36 is installed at the bottom. The air blower 52 receives the air, and the air sucked by the cooling chamber 36 facing the heat absorption surface of the pel- tine unit 26 is cooled. Cooling by sending order air. That is, the cooling chamber 36 has an air inlet 38 on the right side, and cooling air passing through the cooling chamber 36 is provided with a duct opening 42 in the optical fuser 28 through a duct from the outlet 40, From here, cooling air is introduced into the optical fuser 28. Further, the optical fixing device 28 is provided with a suction port 44, passes through the duct 46, reaches the dash filter 48, and further passes through the duct 50, and is sucked by the air blower 52. For this reason, the Peltier unit 26 preheats the continuous paper 12 fed into the optical fixing device 28 by the waste heat, and at the same time, when the air sucked by the air pro 52 passes through the cooling chamber 36, the Peltier unit 26 The air is cooled by the heat absorption of the optical fuser, and the cooled air is passed through the optical fuser 28 to cool the optical fuser 28. Here, for the temperature control by the Peltier unit 26, a temperature sensor 45-1, which detects the preheat temperature, a temperature sensor 45_2, which measures the cooling temperature, and also measures the internal temperature of the optical fuser 28 Temperature sensor 45_3 is provided. Further, the line printer 10 is provided with a control unit 54 and a power supply unit 56. A duct 55 is connected to the control unit 54 and the power supply unit 56 from the cooling chamber 36, and the cooling air is fed by suction by the air pro 52 to cool the unit.

FIG. 3 is an enlarged view of the part of the line printer 10 shown in FIG. The pelchenit 26 has its waste heat surface 74 disposed toward the paper transport path 24, and after the heat from the waste heat surface 74 heats the continuous paper 12 passing along the transport path 24, , So that it enters the optical fuser 28. The lower side of the perchenite 26 is a heat absorbing surface 76, and the cooling chamber 36 is arranged in contact with the heat absorbing surface 76.

FIG. 4 shows the Peltier unit 26 of FIG. 3 in a plan view. This Peltier unit 26 is made of Mar 1 ow Indastries Inc. and has a thin rectangular Peltier element 2 6-1-2 6-4 mm of vertical X horizontal = 38 mm X 3 O mm size.に in the transport direction: 10 pieces in the row direction and 4 pieces in the transport direction, for a total of 40 pieces. Each of the Peltier elements 26-1 to 26-40 has the following specifications. Become.

Maximum heat 1 1 0W

9 5. C

Maximum cooling capacity-36 ° C

Response speed .10 ° C / min (both cooling and heating at 25 ° C)

Becomes Of course, the number of Peltier elements used for the pel-unit 26 is determined so as to have an appropriate size exceeding the width of the paper transport path 24 for the line printer 10 shown in FIG.

FIG. 5 shows a structure of a peltier element 26-11 used in the pelunit 26 of FIG. 4, in which different types of metal N and metal P are joined together and connected to a DC power supply 27 to allow current to flow. . To explain the details of the Peltier element 0, the following equation is generally known as an equation expressing heat generation by the Peltier effect.

E = I + Sg'radT (1)

Q = π · I— a 'gradT, TT = S · T (2)

QO = T · I · gradT, T = T · (d S / dT) (3) where S is the Seebeck coefficient

7Γ is the Peltier coefficient

Is the Thomson coefficient

κ is the thermal conductivity,

P is electrical resistivity

E is a vector indicating the magnitude of the electric field ί

I is a vector that indicates the magnitude of the current. "

Q0 is the heat absorption rate

Τ is temperature

gradT is the temperature gradient In Eq. (1), the vector amount E, which indicates the magnitude of the electric field when there is no temperature gradient, is a value obtained by the well-known Ohm's law.

E = p 'I

Is equal to The vector amount E, which indicates the magnitude of the electric field when there is a temperature gradient, is such that electrons in a place with a high temperature have a large momentum, so electrons flow from a higher temperature to a lower temperature, and It has a positive potential and the lower temperature has a negative potential. In the case of holes, the opposite is true, and the (S-gradT) of the two terms on the right-hand side corresponding to that value is added to · I) of the one term on the right-hand side. When the power supply 27 is connected to the Peltier element 26—11, in which different types of metal N and metal P are joined as shown in Fig. 5, and the current I does not flow through the power supply 27, the magnitude of the electric field can be calculated by equation (1). The vector quantity indicating

E = SgradD

When a temperature difference of (Tl-T2) is given by metals P and N, a potential difference of (VI-V2) is generated. This is the principle of a thermoelectric generator.

In equation (2), the amount of heat when there is no temperature gradient and current I flows is

Q = I

Becomes This is because when electrons are extracted from a substance having electrons with low energy to a substance having electrons with high energy, only electrons with high energy come out, so electrons with low energy remain behind Will be. Considering the calorific value at that time, the temperature drops in a substance that has electrons with low energy, resulting in a difference in calorific value between both substances. This is the Peltier effect. At this time, the Peltier heat Q is a force that is carried in the same direction as the direction of the current I, and the Peltier coefficient has a positive or negative sign depending on the direction of the current I. When a current I is applied to the Peltier element 26-11 by the power supply, in the region of the metal N of the Peltier element 26-11,

Qn = 7Γ η

Heat flows in the region of metal P, which is different from metal N

Qp = π pI

Heat flow. Therefore, at the junction of metal N and P

π τι 一 π ρ ~) I

The difference in the amount of heat comes out. This amount of heat generates heat on one side of the joint and on the other side It absorbs heat, but the difference changes the temperature of the junction, so when this is negative, it becomes the principle of electronic cooling. Therefore, the metal P side of the Peltier element 26-11 becomes the heat absorbing surface 76, and the metal N side becomes the waste heat surface 74.

Here, in order to make a Peltier device with good thermoelectric efficiency, the ratio of the heat taken from the load to the consumed power, that is, the cooling effect coefficient (COP) shown in the following equation, is increased. , Good l <, ₀ _np — Tc (4) Re Th — Tc (1 + Z'Tm + ls ²

Z =

κρ (5) where Z is a figure of merit for judging the quality of thermoelectric material

T c is the temperature of the cold junction

Th is the temperature of the hot junction

Tm is the average temperature of the cooling element. The actual Peltier element is based on these values, such as B i (bismuth), Sb ₂ (antimony), Te ₃ (tellurium), B i + Te (bismuth + tellurium), etc. It is made using metal. The temperature control is determined by the current flowing through the Peltier element, and the response time is as fast as 2 ° C / sec (both cooling and overheating in a 25 ° C environment), so fine temperature control is achieved by simple feedback control. Is possible.

FIG. 6 shows a line printer according to another embodiment of the present invention in which a pel-unit 26 provided as a pre-heat unit is pre-heated by using waste heat from an optical fixing device 28. In the line printer 10, a preheating chamber 82 is provided below the luminaire 26 provided in front of the optical fixing device 28, and the preheating chamber 82 is externally passed through the optical fixing device 28 by suction using an air filter 52. Pelchenit 26 is preheated by passing the introduced air through. That is, the optical fuser 28 is The air introduced from outside by the air blower 52 is cooled by passing through the inside of the optical fixing device 28, and is sent from the inlet 86 to the preheating chamber 82. For this reason, the air heated by the waste heat by the light emission drive of the flash lamp 30 of the optical fixing device 28 is sent to the preheating chamber 82. In the preheating space 86 above the preheating chamber 82, a perchenit .26 is provided.

Further, a control unit 54 and a power supply unit 56 are connected to the suction side of the residual heat chamber 82 by a duct 94. For this reason, the preheated chamber 82 is also fed with air that has been warmed up by the porcelain unit 54 and the power supply unit 56 to preheat the pel chenit 26 and at the same time as the control unit 54 and the power supply unit. 5 6 Chill out!].

'Fig. 7 is an enlarged view of the Peltier unit 26 and the optical fuser 28 in Fig. 6. In the Pelchenit 26, the waste heat surface 74 is arranged toward the paper transport path 24, and the lower heat absorption surface 76 is arranged in the preheated space 102 above the preheat chamber 82. . The preheating chamber .82 includes an introduction section 88, a champ section 96,98,100, and a discharge section 90. The chamber section 96 on the introduction section 88 side and the chamber section 100 on the discharge section 90 side face the paper transport path 24 side. Therefore, the paper from the chamber sections 96 and 100 is heated by the heat from the chamber sections 96 and 100. The pre-heating of the continuous paper 12 passing along the transport path 24 is performed. The chamber section 98 faces the preheating space 102, where the heat absorbing surface 76 of the velcher unit 26 is located, so that the preheating from the chamber section 98 causes the heat absorption of the pelchenit 26. Preheating is performed to raise the temperature of the surface 76.o When the temperature of the heat absorbing surface 76 of the perforated unit 26 is increased by the preheating chamber 82 in this manner, the cooling effect on the right side of the cooling effect coefficient COP of the above equation (4) is obtained. The contact temperature Tc is increased, thereby increasing the cooling effect coefficient COP, so that the temperature of the waste heat surface 74 in the Berch II unit 26 can be made higher. At the same time, since the waste heat of the optical fuser 28 is used for the preheating chamber 82, the effect of cooling the optical fuser 28 by the flow of air passing through the optical fuser 28 for this preheating is obtained. can get.

FIG. 8 shows the preheating chamber 82 of FIG. The preheating chamber 82 has a box-shaped hollow space 102 in the upper part, and a multi-unit 26 is fitted and fixed in the upper part of the preheating space 102. Perunit 26 is shown in Figure 4. As described above, for example, 40 Peltier elements 26-1 to 26-40 are arranged in a 40 × 4 array. An introduction section 88 and a discharge section 90 are provided at almost diagonal positions of the preheating chamber 82, and the air heated by the waste heat of the optical fixing device 28 introduced from the introduction section 88 is supplied to the inside of the preheating chamber 82. After passing through, the air is sucked from the discharge section 90 with an air blower.

Next, specific embodiments of the present invention will be described. The Bellchenit 26 having the configuration shown in FIG. 4 is mounted on the line printer 10 shown in FIG. In this case, it is assumed that a 5000 LPM (second / minute) line pudding is installed as the line pudding 10. When a flash voltage of 1950 volts is applied as a 5000 LPM line pudding light fixing device 28 equipped with a belt tune 26, the toner fixing ratio (%) of the light fixing device 28 with respect to the preheating temperature by the pel tune 26 is The characteristic shown in FIG. 9 is obtained. Here, assuming that the target fixing rate when the optical fixing unit 28 is used is 80%, the pre-heating temperature exceeds the target fixing rate of 80% when the preheating temperature exceeds 40 ° C, and thereafter, the fixing rate of 85% is maintained at about 50 ° C. When the preheat temperature further rises, the fixing rate rises to 90%, but when the preheat temperature exceeds 100 ° C, the fixing rate power decreases. Therefore, as the preheat temperature by the peltunit 26 used in the present invention, the lower limit temperature of use is T1 = 50 ° C, the upper limit temperature is T2 = 100 ° C, and Tl = 50 ° C to T2 = The preheat temperature should be set in the range of 100 ° C.

Here, the following Example 1 and Example 2 are performed for the line printer of FIG.

[Example 1]

For the line printer in Fig. 1, a flash voltage of 1950 volts was applied to the optical fuser 28, and from the relationship between the preheating temperature and the fixing rate in Fig. 9, the temperature of the waste heat surface of the Peltier element in Peltunit was 90 ° C. The cooling surface temperature is set to 135 ° C. as described above, and cooling air is supplied to the optical fixing device 28 in lm ³ Z. As a result of printing at 500 OLPM using preheating and fixing unit cooling under these conditions, it showed excellent fixability even when the toner adhesion amount on paper was 0.9 mgZcm ² . Also, in continuous printing, as shown in Fig. 10, the temperature of the optical fuser rises only to about 70 ° C with an increase in the number of printed sheets, and the internal temperature of the optical fuser 28 is sufficiently low that the optical fuser is damaged. Etc. did not occur.

[Example 2]

The line printer of FIG. 1, lower the flash voltage to 1500 volt, conditions other than that their is a result of printing in the same as in Example 1, good toner adhesion amount on the paper even 0. 9 mgZ cm ² The fixing property was shown.

[Example 3]

For the line printer that preheats the Peltier unit 26 using the waste heat of the optical fuser 28 in Fig. 6, the flash voltage was set to 1500 port as in the second embodiment, and the optical fuser 28, control unit 54, and power supply As a result of printing using the heat generated in the unit 56 for preheating the pelchenit 26, good fixability was exhibited even when the toner adhesion amount on the paper was 0.9 mgZcm2.

[Example 4]

For the line printer 10 in Fig. 6, the flash voltage was set to 1950 volts, and the preheating was performed using the waste heat of the optical fuser 28, controller unit 54, and power supply unit 56 under the same conditions as in Example 3. As a result of printing, the toner showed good fixability even when the toner adhesion amount on the paper was 0.9 mg / cm ² , and the optical fixing device 28 was not damaged by the temperature rise. .

To clarify the effectiveness of Examples 1 to 4, the following Comparative Examples 1 to 5 were printed.

[Comparison 树 1]

As for the line printing shown in FIG. 1, printing was performed under the same conditions as in Example 1 without performing pre-printing by the pelchenit 26 and cooling the optical fixing device 28. As a result, the amount of toner adhering to the paper was 0.9 mgZcm ^2. Thus, satisfactory fixability could not be obtained, and as shown by the characteristic 106 in FIG. 11, the temperature of the optical fixing device 28 increased during continuous printing, and the flash lamp 30 as the light source of the optical fixing device 28 was damaged.

[Comparative Example 2]

Using a ceramic panel heater as the pre-unit, printing was performed under the same conditions as in Example 1. As a result, the toner adhesion amount on the paper was 0.9 mg / cm ² in the initial stage when the temperature of the optical fuser was low. Characteristics of Fig. 11 As shown in 108, the temperature of the optical fixing device was increased by continuous printing, and the flash lamp 30 as the light source of the optical fixing device 28 was damaged.

[Comparative Example 3]

The line printer of FIG. 1, as a result of printing in the same conditions as in Example 2 without preheating, the amount of toner deposited on the paper is 0. S m gZ cm ² ~0. Up to 4 mg / cm ² A fixing amount occurred in the toner adhesion amount.

[Comparative Example 4]

The line printer in Fig. 6 was printed under the same conditions as in Example 3 except that preheating was not performed.As a result, the toner adhesion amount on the paper was 0.9 mg / cm ^{2 to} 0.4 mg gZ cm ^2. The fixing amount occurred at the toner adhesion amount up to.

[Comparative Example 5]

The line printer of FIG. 6, L such perform preheating and preheating, except result of printing the same conditions as in Example 4, the amount of adhered toner 0. 9 m gZ cm ² in satisfactory fixability on paper As in the case of the characteristic 10.6 in Fig. 11, the temperature of the optical fixing device 26 increased during continuous printing, and the flash lamp 30 as the light source of the optical fixing device 26 was damaged.

The above Examples 1 to 4 and Comparative Examples 1 to 5 are summarized as shown in the table of FIG.

FIG. 13 is a flowchart of the pre-heat temperature control of the pel-unit 26 by the control unit 54 provided in the line printer 10 of FIGS. When the apparatus is started by turning on the power of the line printer or the like, the presence or absence of the apparatus standby state is checked in step S1, and if not, the presence or absence of the printing start is checked in step S2. Until the start of printing, the standby temperature setting control 110 of steps S7 to S11 is performed. That is, the preheat standby temperature is set in step S7, and it is checked in step S8 whether the temperature detected by the temperature sensor matches the preset temperature.If not, the measured temperature is set in step S9. Check if it is higher or lower than the preheat set temperature. If it is higher, in step S10, the control current flowing through the Peltier element is reduced to lower the temperature. If the temperature is low, increase the control current flowing through the Peltier element in step S11. To increase the temperature. As a result, the pre-print temperature by the pel-unit 26 is maintained at the set temperature in a standby state before the start of printing.

When the start of printing is determined in step S2, the pre-heat temperature is set in step S3. In this embodiment, the preheat set temperature is, for example, 90 ° C. Subsequently, the preheat temperature is measured by the temperature sensor in step S4, and is compared with the set temperature in step S5. If the temperature matches the set temperature, printing is started in step S6, and steps S4 and S5 are repeated during printing. If the preheat measurement temperature does not match the set temperature in step S5, the preheat temperature setting control 1 12 in steps S12 to S17 is performed. That is, printing is stopped in step S12, the preheat temperature is compared with the set temperature in step S13, and if the temperature is high, the applied current to the Peltier element is reduced by, for example, 10 mA in step S14. In step S15, the preheat temperature is measured, and in step S17, it is checked whether or not the temperature matches the preheat set temperature. If the temperature is still high, the process returns to step S14 again, and further reduces the current flowing to the .1 O mA Peltier element.In step S10, until the measured temperature matches the set temperature, the process proceeds to step S12. , S13, S14, S15, and SI7 are repeated.

On the other hand, if the measured temperature is lower than the preheat set temperature in step S13, the applied current to the Peltier element is increased by 1 O mA in step S16. Then, the preheat temperature is measured in step S15, and the set temperatures are compared in step S17. Steps S12, S13, S16 are performed until the measured temperature matches the set temperature. , S 15 and S 17 are repeated.

Note that the present invention is not limited to the above-described embodiment, and includes appropriate modifications that do not impair the objects and advantages thereof. Further, the present invention is not limited by the numerical values shown in the above embodiments.

[Industrial applicability]

As described above, in the printing apparatus of the present invention, by performing preheating for warming the paper at a stage before the optical fixing device by the waste heat of the Peltier element, even if the flash voltage of the optical fixing device is lowered, the toner fixing property can be reduced. Can be stably maintained. Also Peltier By preheating the paper using the waste heat of the device and simultaneously cooling and supplying air to the optical fuser using the heat absorption of the Berch II device, the temperature rise of the optical fuser can be sufficiently suppressed, and Damage due to rise in temperature of the vessel can be reliably prevented.

Also, by preheating the paper in front of the optical fuser due to the waste heat of the Peltier element and using the waste heat from the optical fixer and power supply unit control circuit to preheat the pelunit and the paper, the optical fuser can be used. Even if the flash voltage is lowered, good fixability is maintained without impairing the fixability of the toner, and at the same time, the inside of the optical fixing device, the power supply unit control circuit, and the like can be cooled.

Furthermore, utilizing the point that high responsiveness to temperature can be obtained by the current flowing through the Peltier element, finer and more accurate preheating temperature control can be performed, and stable fixing can be obtained.

Claims

The scope of the claims

1. In the printer device,

An electrophotographic unit that develops an electrostatic latent image formed on a photoreceptor with toner and then transfers the developed image onto paper;

An optical fixing device for fixing the toner image transferred on the paper by melting the toner by irradiating strong light;

A pre-unit that is provided at a stage preceding the optical fixing device and uses a Peltier element as a heating medium;

A printer device comprising:

2. The printer according to claim 1, wherein the preheating temperature of the Peltier element due to waste heat is set in a range of 50 ° C to 100 ° C.

3. The printer device according to claim 1, further comprising a cooling unit for cooling the optical fixing device using air cooled by heat absorption of the Peltier device.

4. The printer according to claim 3, wherein the cooling unit comprises:

A chamber arranged in contact with the heat absorbing surface of the Peltier element;

A cooling system that introduces air in the apparatus into the chamber, cools the air, and then passes the air through the optical fixing device;

A printer device comprising:

5. The printer according to claim 3, wherein the cooling unit further uses the cooled air for cooling a power supply unit and a control unit of the apparatus.

6. The printer device according to claim 1, further comprising a residual heat unit for preheating the Peltier element of the preheat unit using waste heat generated in the optical fixing device.

7. The printer device according to claim 6, wherein the residual heat unit includes:

A chamber disposed on a heat absorbing surface of the Peltier element via a residual heat space, and a residual heat system for introducing external air into the champer through an optical fixing device and residual heat;

A printer device comprising:

8. The printing apparatus according to claim 6, wherein the residual heat unit further preheats the Peltier element of the preheat unit using waste heat generated from a power supply unit and a control unit. .

9. In a fixing method of a printer device, an electrostatic latent image formed on a photoreceptor by an electrophotographic unit is developed with toner, and then transferred onto paper and then fixed.

A fixing method for a printer apparatus, comprising: performing preheating using a Peltier element as a heating medium before melting a toner by irradiating strong light with an optical fixing device to fix a toner image on paper. .

10. A printer according to claim 9, wherein the pre-heating temperature of the Peltier device due to waste heat is set in a range of 50 ° C to 100 ° C. Device fixing method.

11. The fixing method for a printer device according to claim 10, wherein the optical fixing device is cooled by using air cooled by heat absorption of the Peltier device. .

12. The method according to claim 10, wherein the Peltier element is preheated using waste heat generated in the optical fixing device.