JPS5843478A - Heat fixing device - Google Patents

Abstract

PURPOSE:To enhance heat efficiency of heating means with a simple structure as well as to cut off waste of heat, and further to suppress rise of temp. of a part not passing paper, by movably mounting the heating means in the direction of the shaft of a fixing roller. CONSTITUTION:A fixing roller 1 is heat controlled with cartridge heaters 131, 132, and 14, etc., This heater 14 is movable in the direction of the shaft of a roller 1, normally located to the left or the like, when the detection temp. of a temp. detector 31 reaches a prescribed temp. necessary for fixing, a motor 26 is energized through a comparator 38 to move the heater 14 to the right with a wire 12, or the like. When the detection temp. lowers, it is returned to the left by the elastic force of a spring 11 to respond to size of copying papers and a temp. state of the fixing roller 1, thus permitting the heat efficiency of the heaters to be enhanced by heating applied only to the necessary part and only at the necessary time, waste of heat to be lowered, and further, temp. rise of a part not passing the paper to be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a support piece that supports and supports a toner image.
The present invention relates to a heat fixing/fixing device which uses heating by a means to apply an electrolytic layer to a support material.

2. Description of the Related Art Conventionally, a pair of fixing rollers having a built-in heating heater or an external heating means has often been used as a heat fixing device. Regarding the heaters of such heat roller foot M devices, most of them have a built-in cylindrical halogen heater (because they heat the width of the maximum paper size that can be passed through the fixing device, for example, If the long and horizontal direction of Japanese Industrial Standard 841?-1 size paper is the maximum, there is 1564-'Q, and if you send 4 sizes of 257-width paper, the difference in temperature will be 107-mm.9, continuous high-speed machine When passing paper, the temperature should be 70 to 8 higher than the set temperature.
The temperature may rise by 0°C, which has the following disadvantages. usually,
In the case of thermal rollers, at least one of the rollers has a metal core coated with an elastic material such as silicone rubber, which causes the adhesive layer to spread and deteriorate significantly. Also, the heat from the heater is inefficient (wasted without being used).

Therefore, a method has been proposed in which several heaters are used depending on the size of the transfer paper, and a method in which the interior of 11 heaters is divided into several parts according to the size of the transfer paper. In the former case, since multiple heaters are built into the roller, there is a risk that not only will the device be severely damaged, but also overheating will occur. This is especially noticeable when the heating is too high and when paper is passed, and in order to solve this problem, it is necessary to apply more heat than is normally required.

Regarding the latter, there are few fixing devices #iaa that have been put to practical use because of the difficulty in manufacturing the heater. Furthermore, because there is a large temperature difference between the energized and non-energized parts of the beater, sagging occurs and the tube may be damaged.

The present invention has been made in view of the above problems, and aims to improve the thermal efficiency of the heating means, reduce wasted heat, and further suppress the temperature rise in the non-sheet passing area.
jJ.

Hereinafter, the present invention will be explained in more detail with reference to the drawings. Fig. 1 illustrates one embodiment of the present invention, in which a thermally conductive hollow roller whose surface has been treated to prevent offset is made rotatable by a roller support member 2.3, which is made of silicone. A toner image support material is held and conveyed between a pressure roller 11 having an elastic material such as rubber on its surface, and the toner image is heated and fixed on the support material. Fixing roller 1
A concentric heater holding tube 4 is provided inside the tube, and both ends of the tube are supported by identification members 5.6.

71ka2-1, h-p-A'11. □４ (7)l
'3*#, and movement of the fixing roller in the axial direction is regulated from the front and back by Nasara screws 8 provided at two locations on the heater holding tube 4. Further, a compression spring 11 is provided inside the collar 7, and the collar 7 allows this spring 1 to be compressed.
1 is fixed at one end to prevent it from being pulled out from the collar 7, and the other end is pressed by a sliding disc 10.

This sliding disk 10#i is movable along the guide groove 7m of this collar 7, and its movement is applied by the attractive force of the wire 12 connected to its central portion and the spring 11. Further, a cartridge heater 14, which is provided on the sliding disc 10 between the printer holding tube 4 and the hollow part of the fixing roller, and is movable in the axial direction thereof, is stopped.

In this embodiment, the length of the cartridge heater 4 is approximately half the length of the paper used (preferably slightly smaller than the half length). □1゜9 car cross enemy・t・1. , Ka. , Yu. 1 o. -, the direction is a solid line, and the broken trout moves forward as shown by each arrow. This moving company is secured without any problem by the guide grooves 4m and 7m, but at the same time, the heater cable bar heater cable 35. can be moved safely. Two cartridge heaters 151 and 131, which are connected to the heater holding tube 4, are fixed in the same way as the above-mentioned cartridge heaters, in the gap with the fixing roller 21 and near the inner surface of the fixing roller. Corresponds to both ends of the direction. - On the other hand, the wire 12 is wound around the pulley 16, and the Korean one-way clutch 17 is press-fitted into the pulley 16 and engaged with the shaft 18. Axis 18 fixed plate 19
, 20 via bearings, and the bi/21
The friction plate 22 and the fixed plate 20 move only in the axial direction due to
It is frictionally coupled with a plate 25 fixed to the shaft 18.
A load is applied to the rotation of. Frictional force is compression spring 2
4 and the pressure tube 25. Pulley 16KF
It has a single gear and meshes with a single gear 27 fixed to the output shaft of the motor 26. Further, the pulley 16 has a projection, and the number of revolutions of the pulley 16 is detected between one sensor 28 and the other. 9 years 12 by input of motor 26
is wound up and moves in the direction of the arrow of cartridge heater 14If1.

Additionally, a temperature detection sensor 2 is provided on the outer peripheral surface of the fixing roller 1.
9. 30, 31, and 32 are the positions corresponding to the cartridge heater 131 #131K, near the other end of the B5 size support material (one side reference, that is, the support material is transported as the sensor 29 side), and the other end of the B4 size support material. Located nearby. 37 is connected to the control means; a comparison means 58 for comparing with a set standard; and an output control means 59 for increasing or decreasing the output of each heater in response to the signal; , a control system 40 that detects the size of paper used for copying, determines the sensor output for the heater in use according to the signal, and turns on and off the heater, as well as detects and controls the position of the heater. The sensor 29 controls the on/off state of the cartridge heater 151, and also controls the position of the heater 14 as well as the on/off state of the cartridge heater 14 made by sensor 30. The sensor 31 also serves as a control not only for FiBS size sheets but also for A4 size (A3 size) sheets.

Now, when the fixing device is warmed up, the cartridge heat
1-13t e 13s When e14 is turned on, the sensor 29.30 detects its temperature. For example, when the detected temperature reaches the set temperature of 150°C, the comparison means 38 sends a signal to the output control means 39 and the heater 13111
38a is turned off and turned on again when 145°C is detected. The heater 14Fi first heats the left side in the state shown in FIG. 1, and when the sensor 31 detects 150°C, the comparison means 68
A signal from the sensor 32 is sent to the control system 40, which operates to rotate the motor 26 and move the heater 14 to the right side to heat the right side.
Setting '□, □ Set the constant temperature to 0 in the support material passage area? If the temperature is higher than 111F degrees (for example, 155 degrees Celsius), when the sensor 31 detects the lowest fixable temperature, for example 145 degrees Celsius, during the heat action, the control means and system (38, 40, 39) will activate the wire release. The heater 14 is then moved to the left by the spring. By repeating this process, 1
When the temperature of 55° C. is detected, the heater 14 is turned off at the end of the warm-up, and a signal indicating that copying is possible is sent. Next, when copying B4 size paper, follow the above sequence and the position on the left side of the heater 14 will be the reference position, but in this case B5
The set temperature #i1 for the portion excluding the size paper is the same as the set temperature at this reference position, and the ON signal of the heater 14 from the sensor 32 is 150° C. as in the above example.

Next, when copying A4 size paper with the fixing surface maintained at 150"C, the heater 14 is retracted to the right position and turned on and off while maintaining that state. Repeat.However, when the sensor 31 detects the lower limit temperature of -6 for fixing, 2145°C, the A4 size paper moves to the left side, which is the area where 1 = =, and heats the left side. You can immediately make copies of B4 size paper.

During this movement, it is a load for the heater 14 to move smoothly when the pressure of the friction plate 11 (compression) spring 11 provided on the shaft 18 is released, and the one-way clutch 17 is used only when the heater 14 moves to the right. It is configured to be loaded. Therefore, when the wire 12 is wound up by the motor 26, the friction load line does not work, resulting in low torque of the motor 26, long life, and no transfer or breakage of the heater 14, no slack in the wire 12, and no impact caused by bumping.
It can be done smoothly.

In addition, in this embodiment, the cartridge heater 131°131
are provided at both ends, and the purpose of this is to deal with the case where there is a large amount of heat escaping at both ends of the foot extension roller. tThis cartridge heater 131 e 13fi has the effect of strengthening the heating power of the end of the cartridge heater 14, and the intersection part due to the movement of the heater 14, (when the heater length is greater than half the roller length) or this example This is because fixed heaters are installed at both ends so that the temperature can be heated independently depending on the purpose. (For example, a temporary heater 13t that uses the entire roller length,
Use both 13s and B5. A4. (For A3 size, the heater 131 is used, etc.) Therefore, in this embodiment, the heater structure is such that the heating power at both ends of the heater 14 is slightly weaker than that at the center.

Unless a heating means such as the cartridge heater 131 @ 131 is fixed at both ends with the fixing member 15, the humidity distribution of the cartridge heater 14 is such that the central part has a lower calorific value than both ends. In addition to the case where the cartridge and m-13s are moved in the same way as the cartridge heater 14 (for example, using drive coupling means such as cams and gears), the A4 of the embodiment shown in Fig. 1 can be moved.
(A3) A combination in which the cartridge heater 133 is positioned to the right 11 of the cartridge heater 14 to heat the roller central region during size fixing is more preferable.

Further, at this time, it is sufficient to move the cartridge and the roller 131a in the same manner as described above each time the roller is heated to a sufficient temperature.

In this embodiment, the method of moving the supporting material in the advancing direction is changed depending on the type of the supporting material supporting the ore and toner image, and the present invention is not limited to this. The feature is that a heating means is used, and other configurations can be used in various ways.

As described above, the present invention solves the drawbacks of the prior art and makes it possible to effectively utilize heat and maintain the fixing performance of the fixing device over a long period of time.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention. 1- is the fixing roller, 2.3 is the roller support tube, 4 is the heater holding tube, 5.6 is the same city part, 7 company colors, 4a, 71
#1 guide groove, 10#i sliding disk, 11#'i spring, 12
13t * 13m, 14F1 car) Ridge heater, 15ti fixed component, 26 is motor 29.50.31.32 temperature detection sensor, 3
4゜35.36 is a heater cable, 37 is a control means,
5.81i comparison means・39 is out and control means・40ti
ll control system. 1 ′(

Claims (1)

[Claims] A non-heat fixing device characterized by a heating means that is movable in a direction intersecting a direction in which a support material supporting a toner image travels.