JPS6083978A - Fixing device - Google Patents

Abstract

PURPOSE:To prevent deformation of an image supporting body to prevent dirt of a fixing roll by setting the position of a contacting part of feeding rolls on the extension of the tangent of the fixing roll or in a position which is shifted from this extension to the side of an image forming face of the image supporting body. CONSTITUTION:The position of a contacting part B between feeding rolls 14 and 15 is set on the extension of a tangent 16 of the first fixing roll 11 placed in the side of the image forming face of an image supporting body 4 in an exit A of a nip part 9 between fixing rolls 11 and 12 or in a position which is shifted from this extension to the side of the image forming face. That is, the position of the contacting part B is so set that an angle gamma formed between a reference line 18, which connects the exit A of the nip part 9 between fixing rolls 11 and 12 and the contacting point B between feeding rolls 14 and 15, and a tangent 19 of the contacting point B between feeding rolls 14 and 15 is 0 deg.<gamma<90 deg.. Thus, deformation of the image supporting body and dirt of fixing rolls are prevented to perform a good and stable fixing operation for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a fixing device for fixing an unspecified image, for example, in a facsimile, an electronic copying machine, or the like.

[Technical background of the invention and its problems]

Generally, in an electronic copying machine, etc., once ++! is applied to the photosensitive drum 1 as shown in FIG. ++ A developer image (toner image) 2 as I'l is formed and this developer image 2 is transferred onto an image support 4 such as plain paper by the transfer device &3. After this, the image support 4 is removed by a peeling device 5.
The developer image 2 is peeled off from the photosensitive drum 1 and sent to a fixing device 6 by the action of the developer image support 4, and the developer image 2 is fixed on the image support 4 and discharged onto a paper discharge tray 8 outside the main body 7 of the device.

In addition, the above-mentioned joseki fR8 includes a first roller made of a rigid roller such as a Teflon roller and an elastic roller 2 such as a silicone rubber roller with a built-in heat source 10 so as to form a nip (planar pressure welding portion) 9 at the rolling contact portion. , second fixed roller 11,1
2 is disposed, and the image support 4 is caused to pass through the nip portion 9, whereby the developer image 2 on the image support 4 is heated and pressurized to be fixed. Then, remove the i# image support 4 with the peeling nail 1.
3, the paper is peeled off from the first fixed roller 211 and sent to the contact portion of the paper ejection rollers 14 and 15, which are provided in a rolling contact state on this delivery direction side, and is ejected onto the paper ejection tray 8. It is composed of

However, since the image support 4 that has passed between the fixing roller pair 14.15 tries to proceed along the extension line of the tangent line 16 at the exit point A of the nip portion 9, the image support 4 that has passed between the pair of fixed rollers 14. If the position of 15 is below the extension line of the line 16, that is, on the opposite image forming surface side of the image support 4, the second
As shown in the figure, the movement of the image support 4 is suppressed downward.

At this time, the deformation I of the fixed rollers 11 and 12 provided to form the nip 9 is not uniform throughout, and the peripheral speed is faster in the center and slightly slower on both sides. is normal, and moreover, it is usually fixed lodging roller 1
1 and 12, the image support 4 is sufficiently heated.

For this reason, when the image support 4 is pressed downward, wavy wrinkles 17 and
... is likely to occur on the image support 4, and as shown in FIG. If the developer image 2 is present in this area, there is a problem that the developer will melt and be transferred to the fixing roller 11, preventing good fixing.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and its object is to provide a fixing device that can prevent the image support from getting hairy and the foot end rollers from getting dirty by simply adjusting the positional relationship. This is what we are trying to provide.

[Summary of the invention]

In order to achieve the above object, the present invention allows the image on the image support to be formed in a fixed manner by passing the image support through the nip portion of a fixed roller provided so that a nip is formed at the rolling contact portion. At the same time, in a fixing device that feeds the image support that has passed through these fixing rollers to the contact portions of feed rollers that are provided in rolling contact with each other in the sending direction side, the position of the contact portions of the feed rollers is adjusted as described above. 4rO
-iI at the exit of the first leg of -2! The structure is such that it is located at a tangent 1 fM extension line of constant 10-L on the image forming surface side of the II image support, or is shifted toward the image forming surface side of the image support.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

Adjust the position of the contact portion B of the feed rollers 14 and 15 to the fixed roller 1.
A first constant 10- located on the 1iln image forming surface side (upper side) of the image support 4 at the exit A of the nip portion 9 of 1 and 12.
On the extension line of tangent line 16 of la 11 or on the image forming surface side (
The configuration is such that it is located at the K position (upper side).

(The drawing is on the extension line.) That is, the fixed roller 11
, 12 nip part 9 [JA and feeding loan 14.15
base line J8 connecting the contact point B of and the feed roller 14,
The angle r formed by the contact point B of 15 with the tangent 19 is 0° and γ<9
It is set so that it is 0°.

The planting roller 11 is an aluminum roller whose surface is coated with a resin such as Teflon (part name), and the planting roller 12 is an aluminum roller with silicone rubber Fl coated on its surface. A peeling claw 13 provided with a guide plate 20 is in contact with the fixed roller 11.

After passing through the fixed stone rollers 11 and 12, the image support 4 is peeled off from the fixed stone roller 11 by the peeling claw 13, and then guided by the guide plate 20 to the feed roller 1.
It is led between 4 and 15. At this time, the image support 4 attempts to advance along the extension line of the tangent 16 to the exit A of the nip portion 9. There is no longer any pressure on the bottom side, and wrinkles called 17.
The occurrence of ... can be prevented.

Further, it is possible to prevent the rear end side of the image support member 4 from being lifted and the image forming surface slidingly contacting the roller 10-211 which has a temperature of about 200 degrees and staining the roller 1.

〔Effect of the invention〕

As explained above, according to the present invention, the image on the image support is formed by passing the image support through the nip of the provided foot 10-ra so that a nip is formed at the transition portion. In a setting device in which the image support that has passed through these fixed loss rollers is sent to the contact portion of feed rollers that are provided in rolling contact with each other in the sending direction side, the position of the contact portion of the feed rollers is determined. 111 of the image support from the tangential extension line of the fixed roller on the image forming surface side of the image support at the exit of the nip portion of the fixed roller.
0 The position is set to be shifted toward the image forming surface side.

Therefore, it is possible to prevent deformation of the image support member and the staining of the theoretical roller by simply adjusting the positional relationship, etc., by 9.1 times t'ξ, and it is possible to perform good and stable constant motion over a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view showing a fixed size device incorporated in an electronic copying machine, etc., Fig. 2 is an explanatory diagram showing the entire positional relationship between a conventional fixed roller and a feed roller, and Fig. 3 is a conventional FIG. 4 is an explanatory diagram showing the state in which wrinkles are generated on the image support by the apparatus, and FIG. 4 is a schematic structural explanatory diagram showing one embodiment of the present invention. 2... Image (developer image), 4... Image support, 6...
... Sizing device, 9... Nip, 10... Heat source, 1 No.... First fixed stone roller (rigid body roller 2), 12... Second fixed stone roller (elastic body roller), 14 ...Feed roller (paper discharge roller), 15...Feed roller (paper discharge roller), 16...Tangent line, 18...Reference line, 19...Tangential line, A...Nip section exit, B...Feed roller contact point. Applicant's agent Patent attorney Takehiko Suzue 2nd disability; 3rd verse 1 Figure 4

Claims (1)

[Scope of Claims] (1) The image on the image support is fixed by passing the image support through the nip portion of the fixed roller provided so that a nip is formed at the rolling contact portion, and the fixed stone is In a fixed stone device that feeds the image support that has passed through the rollers to a contact portion of feed rollers that are provided in rolling contact with each other in the sending direction side, the position of the contact portion of the feed rollers is set to a nip portion of the fixed rollers. An electrolayer device characterized in that the electrolayer device is set to be located at an extension line of a tangent to the fixing roller on the image forming surface side of the image support at the exit, or to be shifted toward the image forming surface side of the image support. (2) The angle γ formed between the reference line connecting the nip part protrusion of the fixed roller ['' and the contact point of the feed roller and the tangent to the contact point of the feed roller 2 above] was set to be Oo<90°. A fixed stone device according to claim 1, characterized in that: 0) Claim 1 or 2, characterized in that one fixed roller located on the image forming surface side of the image support is made of a rigid roller, and the other fixing roller is made of an elastic roller. fixing device. (4) The fixing device according to claim 3, wherein the rigid roller is a heat-generating roller having a built-in heat source.