JPH01128083A - Fixing device - Google Patents

Abstract

PURPOSE:To easily perform cleaning and maintenance works by using the hinge part of a casing as the shared open/close fulcrum to divide the casing into a heat roll-side upper casing and a pressure roll-side lower casing by opening and closing. CONSTITUTION:The fixing device casing is divided into a heat roll-side upper casing 11 and a pressure roll-side lower casing 12; and an aperture 11b of an axial supporting part 11a provided on the hinge part of the pressure roll-side lower casing 12 passes a notched part 14a of a shaft body fixed to the hinge part after the heat roll-side upper casing 11 is turned at a prescribed angle around said shaft body, thereby freely attachably and detachably constituting the heat roll-side upper casing 11 and the pressure roll-side lower casing 12. When the fixing device casing is attached or detached, the heat roll-side upper casing 11 is turned in the direction of an arrow C with the outside peripheral part of the shaft body 14 as the center. Thus, jam recovery and cleaning and maintenance processings are easily performed.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a fixing device that heats and fixes an unfixed toner image onto a transfer material such as recording paper, and fixes the unfixed toner image by sandwiching and conveying the transfer material between a heating roller and a pressure roller that rotate in pressure contact with each other. The present invention relates to a fixing device that is applied to image forming devices such as electrophotographic recording devices, laser recording devices, and facsimile machines.

[Background of the invention]

In an image forming apparatus such as an electrophotographic recording apparatus, methods for fixing an unfixed toner image onto a transfer material such as recording paper include, for example, a solvent fixing method, a pressure fixing method, a heat fixing method, etc. Generally, a heat fixing method is often employed in which toner is melted by a heating roller and adhered to a transfer material. In this type of method, a transfer material supporting a toner image, which is an unfixed image, is conveyed while being sandwiched between a heating roller equipped with an internal heat source such as a heater, which rotates in pressure contact with each other, and a pressure roller, which is in pressure contact with the heating roller. The toner is melted and thermally fixed onto the transfer material by pressure and heat from a heating roller. In a general heating roller type fixing device, the heating roller is located on the upper side. The heating roller has heating means such as a heater inside the pipe-shaped metal roller. The pressure roller that comes into pressure contact with the heating roller is formed by wrapping, for example, silicone rubber around the circumferential surface of a core metal. The surface temperature of the heating roller is maintained at around 200° C. by heating means, and the heating roller is rotated in one direction by power. On the other hand, the pressure roller is pressed against the heating roller from behind the transfer material while the transfer material is being fixed, and rotates in a driven manner. Then, while the transfer material passes through a fixing device, the toner image is fused and fixed, and then
It is discharged to the outside.

[Problems to be solved by the invention]

2. Description of the Related Art A jam (paper jam) may occur within a fixing device during operation of an image forming apparatus. When a jam occurs inside the fixing device, it is necessary to quickly remove the jammed transfer material, and for this purpose conventionally the fixing device casing has been constructed so that it can be opened and closed in sections. If the fixing device casing can be opened and closed in sections, the above jam removal process can be easily performed. Moreover, in addition to jam removal, cleaning and maintenance work of various members such as rollers can be easily performed. In the conventional split opening/closing system, for example, in the case of the top and bottom split opening/closing system, an opening/closing shaft is provided at an appropriate location on the side wall of the lower casing.
The upper casing was rotatably attached to the opening/closing support shaft so that it could be opened and closed in sections. However, when cleaning, maintenance, parts replacement, etc. inside the fixing device, it is not sufficient that the fixing device casing is constructed so that it can be opened and closed in sections.

[Means to solve the problem]

The present invention improves the drawbacks in view of the above-mentioned problems, and the fixing device casing is opened and closed in two parts, an upper casing on the heating roller side and a lower casing on the pressure roller side, using the hinge portion of the casing as a common opening/closing fulcrum. In addition,
It is an object of the present invention to provide a fixing device in which an upper casing on the side of a heating roller and a lower casing on the side of a pressure roller are configured to be detachable so that cleaning and maintenance work can be easily performed. The above object is to provide a fixing device in which the fixing device casing can be opened and closed in two parts, an upper casing on the heating roller side and a lower casing on the pressure roller side, using the hinge portion of the casing as a common opening/closing fulcrum. A shaft body having an oval cross-sectional shape having notches on both sides is fixed to the hinge part of the lower casing on the roller side, and a shaft body having the same width as the notch part of the shaft body is attached to the hinge part of the upper casing on the heating roller side. A shaft support for the shaft body having an opening is provided, and after the upper casing on the heating roller side is rotated by a predetermined angle around the shaft body, the opening of the shaft support passes through a notch in the shaft body. This is achieved by a fixing device characterized in that the heating roller side upper casing and the pressure roller side lower casing are configured to be detachable.

【Example】

An embodiment of the invention is shown in Figures 1 and 2a, 2b and 2c. FIG. 1 shows the structure of a fixing device according to the present invention. The heating roller l is forcibly driven and rotated clockwise at a fixed position by a power device (not shown) on the main body of the image forming apparatus. The pressure roller 2 is in pressure contact with the heating roller 1 and is driven to rotate counterclockwise. A transfer material with a toner image transferred onto the upper surface thereof is carried in from the direction of arrow A through the guide of the front guide plate 3 toward the pressure contact portions of both lawns. The transfer material is held between both rollers and conveyed to the left in the figure. At this time, the toner image on the transfer material is
It is melted by the heat generated by the heater 4 built into the heating roller 1 and fixed onto the transfer material. The transfer material with the fixed toner image is carried out from the pressure contact portion of both rollers, and after the toner image is cooled and fixed, it is peeled off from the roller surface by the separating claw 5, guided by the rear guide member 6, and then moved in the direction of arrow B. It is designed to be discharged from the fixing device casing to the outside of the fixing device casing. The heating roller 1 is a pipe-shaped metal roller with an outer diameter of about 22 mm. The pressure roller 2 is a roller having an outer diameter of about 22 mm and has a silicone rubber layer having a thickness of 6.5 mm and a hardness of about 40° formed on the outside of a core metal. The heater 4 built into the heating roller l is
has almost the same length. The amount of heat generated is determined by a contact temperature sensor 7 set on the circumferential surface of the heating roller l.
As a result of the temperature detection, the peripheral surface temperature of the heating roller l is always 2.
It is controlled to be maintained at around 00°C. A cleaning roller 8 is attached to the heating roller l in order to prevent dust such as toner and paper dust adhering to the circumferential surface of the heating roller l from being transferred to a new transfer material and contaminating the toner image.
was placed in contact with the The cleaning roller 8 is installed so as to abut near the uppermost end of the heating roller l. The cleaning roller 8 is a roller made of foamed silicone rubber that is pressed against the circumferential surface of the heating roller 1 without impregnating it with oil or the like, and is driven to rotate to adsorb and remove adhered toner and the like. FIGS. 2a, 2b, and 2c are side views of the fixing device casing showing the attachment/detachment operation state. In these figures, ll is the upper casing on the heating roller side, lla is the shaft support, llb is the opening, 12 is the lower casing on the pressure roller side, 13 is the lower sheet discharge roller, 14 is the shaft body, 14
a is a notch. The fixing device casing of the present invention is divided into an upper casing 11 on the heating roller side and a lower casing 12 on the pressure roller side. After rotating the side casing 11 by a predetermined angle, the heating roller side upper casing 1
Opening 11b of one shaft support 11a provided in one hinge part
The upper casing 11 on the heating roller side and the lower casing 12 on the pressure roller side are configured to be detachable so that they pass through the notch 14a of the shaft body 14 of the casing on the pressure roller side. The heating roller side upper casing 11 is made of a metal plate with a thickness of 1.2 mm, and has the shape of a casing with an open bottom. Heating roller mounting part 1 with heating rollers l provided on both sides
1c and the pivot support 11a. The pressure roller side casing 12 is made of a metal plate with a thickness of 1.2 mm, and has a casing shape with an open top surface. Both sides have mounting portions 12a in which the pressure rows 22 are provided and mounting holes 12b in which the shaft body 14 is fixed. The lower sheet discharge roller 13 is provided on the downstream side in the transfer material conveying direction from the pressure contact portion between the heating roller l and the pressure roller 2, and is configured to collect the transfer material that has been fixed and conveyed by the heating roller l and the pressure roller 2. is ejected from the fixing device. The lower paper discharge roller shaft 15 is a prismatic square shaft formed by bending a metal plate with a thickness of about 1 mm. The cross-sectional shape of the square shaft is a square with a side length of 6 mm. Cylindrical sliding members are fixed to both ends of the lower paper discharge roller shaft 15. The sliding member is a round shaft having a square hole in its center into which the square shaft is inserted. The sliding member is pivotally supported by the shaft 14. The shaft body 14 is a shaft body having an oval cross-sectional shape with a notch 14a on its outer periphery, and also serves as a bearing for the lower paper discharge roller shaft 15. The shaft body 14 is fixed to both sides of the lower casing 12 on the side of the pressure roller. A sliding member of the lower paper discharge roller shaft 15 is pivotally supported on the inner circumference of the shaft body 14, and the heating roller side upper casing 11 is rotatably attached to the outer circumference. FIG. 2b is a side view showing a state in which the upper casing 11 on the heating roller side is opened approximately 30' in the direction of arrow C with the outer peripheral portion of the shaft body 14 as the center of rotation. During normal use, it can be opened to this state. Simple jams (paper jams) can be handled in this open state. In the fixing device of this embodiment, when the heating roller side upper casing 11 is in the 30° open state, a stopper (not shown) is attached to the upper casing 11.
is activated so that the upper casing 11 cannot be opened any more and cannot be attached or detached. During normal use, a general user can open the heating roller side upper casing 11 by 30 degrees. FIG. 2c is a side view showing the state in which the upper casing 11 on the heating roller side is attached and detached. The fixing device of the present invention prevents jams (paper jams) from occurring, cleaning and
When the fixing device casing is attached or detached for processing work such as maintenance, the heating roller side upper casing 11 is rotated in the direction of arrow C about the outer circumference of the shaft body 14. The upper casing 11 on the heating roller side is approximately 60
° When rotated in the direction of arrow C, the opening 11b of the shaft support 11a provided in the upper casing 11 on the heating roller side opens onto the shaft 14.
When the heating roller side upper casing 11 is pulled upward in this state where it can pass through the notch 14a, the heating roller side upper casing 11 is separated from the pressure roller side lower casing 12. The above-mentioned processing work is performed in this state. After the processing operation is completed, the heating roller side casing 11 and the pressure roller side casing 1 are separated by reversing the separation procedure described above.
2 will be combined to restore the original state.

【Effect of the invention】

According to the present invention, a shaft body having an oval cross-sectional shape having notches on both sides is fixed to the lower casing on the pressure roller side, and a shaft support having an opening that can pass through the notch portions of the shaft body is provided on the heating roller side casing. Since the upper casing on the side of the heating roller and the lower casing on the side of the pressure roller are configured to be detachable, it is possible to provide a fixing device in which jamming, cleaning, and maintenance can be easily performed.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a fixing device according to an embodiment of the present invention, and FIGS. 2a, 2b, and 2c are side views of the fixing device casing in a two-part opening/closing state. ■... Heating roller 2... Pressure roller 11...
・Heating roller side upper casing 11a...shaft support 11b...opening 12・
・・Lower casing on the pressure roller side

Claims (1)

[Claims] In the fixing device in which the fixing device casing can be opened and closed in two parts, an upper casing on the heating roller side and a lower casing on the pressure roller side, using a hinge portion of the casing as a common opening/closing fulcrum, the lower casing on the pressure roller side; A shaft body having an oval cross-sectional shape having notches on both sides is fixed to the hinge portion of the heating roller side, and a shaft body having an opening of the same width as the notch portion of the shaft body is fixed to the hinge portion of the upper casing on the side of the heating roller. After providing a shaft support for the shaft body and rotating the heating roller side upper casing around the shaft body by a predetermined angle, the opening of the shaft support passes through the notch of the shaft body. A fixing device characterized in that an upper casing on the heating roller side and a lower casing on the pressure roller side are configured to be detachable.