JPH0544836Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a fixing device used in a copying machine.

[Background of the idea]

In general, a copying device applies light from a light source to the surface of a document on a document table, and irradiates a photoreceptor drum with light reflected from the document surface to form an electrostatic latent image, which is developed into a toner image by a developer. The toner image is transferred to the recording paper that is fed at the right time, fixed, and then discharged outside the machine. The fixing device that fixes the toner image transferred to the recording paper is equipped with an upper roller heated to a high temperature and a lower roller that is pressed against the upper roller.The heat and pressure of these rollers melts the toner image transferred onto the recording paper. It is becoming established. This heating roller rotatably supports a straight pipe on the side frame of the unit via a bearing member, a heater lamp is passed vertically through the straight pipe, and both ends of the heater lamp are held by lamp holders extending from the lamp terminal block. Although a relatively simple structure can be obtained by doing so, there is a difficulty in preventing the straight pipe from coming off. In other words, since straight pipes have limited wall thickness, it is not possible to provide undercuts or cut threads, and it is not possible to use simple fasteners such as E-rings and C-rings. The structure is complicated, making it difficult to assemble, increasing costs, and making maintenance such as roller replacement difficult.

[Purpose of invention]

In view of the above points, the purpose of this invention is to provide a fixing device that improves the ease of assembling a heat roller made of a straight pipe, reduces costs, and ensures speedy maintenance such as roller replacement. It is said that

[Configuration of the invention]

In order to achieve the above object, this invention is a fixing device that uses a straight pipe with a heater lamp running vertically as a heat roller, and the outer end of the straight pipe is provided on the side surface opposite to the notch groove provided on the bottom surface of the fixing device. It is constructed so that it can be stopped by a slip-off prevention member having a base portion and an insertion end that can be fitted into the holes, respectively.

〔Example〕

Next, this invention will be explained based on embodiments shown in the accompanying drawings.

FIG. 1 shows a fixing and paper ejection unit. In this figure, 1 and 2 are upper and lower rollers for fixing, 3 is a cleaning roller in contact with the lower roller 2, and 4 is a paper ejection roller.

As shown in the third figure, the upper roller 1 consists of a straight pipe 7 rotatably supported by a unit side frame 5 via a bearing member 6, and a heater lamp 8 extending vertically through the straight pipe 7.

The outer end of the straight pipe 7 is prevented from coming off by a special ring-shaped slipping prevention member 9. Moreover, the open end 7a of the straight pipe 7
is covered with a conical cover member 11 having a through hole 10 for the heater lamp 8 . This is effective in preventing the heat of the heater lamp 8 from escaping from the open end 7a of the straight pipe 7 and increasing thermal efficiency. This cover member 11 is integrally fixed to a lamp terminal block 12 attached to the unit side frame 5 with screws 12a. A lamp holder 13 holds both ends of the heater lamp 8, and a base end 13b of the lamp holder 13 is fixed to the lamp terminal block 12 together with a power supply connection terminal 14 with a screw 12b.

As shown in FIG. 6, the ring-shaped slip-off prevention member 9 is bent into a substantially trapezoidal shape with the center part of a filament a such as a spring wire as the base and both ends as the side sides, and the center part is used as the base part d. , the ends of both ends are bent inward at substantially right angles to the sides to form insertion ends b and c. Therefore, the falling-off prevention member 9 expands its both ends by utilizing its spring properties, and fits the base d into the notch groove 7d provided in a part of the circumference of the straight pipe 7, so that the pipe 7 The straight pipe 7 can be easily prevented from coming off by fitting the insertion ends b and c into the holes 7b and 7c provided at opposing positions as shown in FIG.

The lower roller 2 is attached to the unit side frame 5 so as to be movable in the vertical direction, and is pressed against the lower surface of the upper roller 1 by a spring 15. The cleaning roller 3 is pivotally supported by the unit side frame 5 so as to be movable in the horizontal direction, and is pressed against the lower roller 2 by an annular spring 17 that is engaged with a hook 16 provided on the unit side frame 5. There is.

18 is a lever whose base end 19a is fitted onto the shaft 3a of the cleaning roller 3, and whose tip end 19b can swing vertically about the shaft 3a; 20 is a box-shaped lever provided integrally with the lever 18; The swinging body 20 is a swinging body, and the swinging body 20 pivotally supports both ends of the lower roller 2 as shown in the second figure. Therefore, when the tip 19b of the lever 18 is pressed downward, the swinging body 20 also tilts together with the lever 18, and the lower roller 2, whose both ends are pivotally supported, descends against the spring 15, and the swinging body 20 tilts together with the lever 18. The pressure is released from the roller 1.

In addition, in the figure, 21 is a recording paper conveyance guide plate;
2 and 23 are guide plates for guiding the recording paper to the contact portions of the upper and lower rollers 1 and 2, and 24 and 25 are paper discharge guide plates.

In the above embodiment, the straight pipe has holes 7b and 7c and a notch groove 7d drilled in advance at the opposite portions of the open end 7a, and the straight pipe is inserted between the unit side frames 5 and 5 via the bearing member 6. , unit frame 5,
5, expand both ends of the ring-shaped slip-off prevention member 9, and insert the base portion d of the slip-off prevention member 9 into the notch groove 7d, and the insertion ends b and c at the ends of both ends into the holes 7b and 7c. Easy to install by fitting it in,
The installation work can be completed quickly.

[Effect of idea]

As explained above, this invention is a fixing device that uses a straight pipe with a heater lamp running vertically through it as a heat roller, in which the outer end of the straight pipe is connected to a cutout groove provided on the bottom surface and a hole provided on the opposite side surface. It features a detachment prevention member that has a base and an insertion end that can be inserted into the straight pipe, which improves the ease of assembling the heat roller made of a straight pipe, reduces costs, and speeds up maintenance work such as roller replacement. This has the excellent effect of ensuring safety.

[Brief explanation of the drawing]

The figures show an embodiment of this invention; Fig. 1 is a side sectional view, Fig. 2 is a plan sectional view, Fig. 3 is a sectional view of the upper roller made of a straight pipe and the mounting part of the heater lamp, and Fig. 4 is a sectional view of the mounting part of the upper roller and the heater lamp. FIG. 5 is a side view of the lamp holder part, FIG. 5 is a sectional view showing how the straight pipe fastener is attached, and FIG. 6 is a front view of the fastener. 1...Upper roller, 2...Lower roller, 3...Cleaning roller, 7...Straight pipe, 7a
...Open end (outer end), 7b, 7c... Hole, 7d
... Notch groove, 8 ... Heater lamp, 9 ... Fallout prevention member, a ... Linear object such as spring wire, b, c ...
Plug end, d...base.

Claims (1)

[Claims for Utility Model Registration] (1) In a fixing device that uses a straight pipe with a heater lamp running vertically through it as a heat roller, the outer end of the straight pipe is provided on a side surface opposite to a notch groove provided on the bottom surface of the fixing device. A fixing device characterized in that the fixing device is fixed by a slip-off prevention member having a base portion and an insertion end that can be inserted into the holes. (2) The slip-off prevention member is bent into a substantially trapezoidal shape with the center portion of the spring wire as the base and both ends as the sides, with the center portion serving as the base and the ends of both ends being approximately perpendicular to the sides. A fixing device that is configured as an insertion end by bending it inward.