JP2001175109A - Fixing device for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly apply oil on an oil applying member. SOLUTION: A fixing device for an image forming device is provided with a heating rotary member (Rh) and a pressuring rotary member (Rp) for fixing an unfixed toner image on a recording sheet (S), the oil applying member 17 for applying a releasing oil on a surface of the heating rotary member (Rh) by coming into contact with the heating rotary member (Rh), an oil supply pipe 14, inside which an oil flow passage is formed and which supplies the oil to the oil applying member 17 and has a plurality of oil outflowing ports 14a formed at prescribed intervals along the oil flow passage and a plurality of axial direction flow passage interrupting member 14b which are provided at outer peripheral surface of the oil supply pipe 14 and prevent the oil flowed out of the oil outflowing ports 14a from transferring along an outer peripheral surface of the oil supply pipe 14 and moving the axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device for an image forming apparatus for fixing a toner image on a recording sheet passing through a fixing area, which is a pressing area where a heating rotary member and a pressing rotary member press against each other. An oil application member that is in contact with the heating rotation member and applies release oil to the surface of the heating rotation member, and is disposed above the oil application member and supplies release oil onto the oil application member. And a fixing device for an image forming apparatus having an oil supply pipe. The fixing device for an image forming apparatus according to the present invention is used in a copying machine, a laser printer, and the like.

[0002]

2. Description of the Related Art As a fixing device for the image forming apparatus, the following technology (J01) is conventionally known. (J01) Technology described in Japanese Patent Application Laid-Open No. 8-137317 This publication has a pair of fixing rolls composed of a heating roll and a pressure roll, and a fixing formed by a pressure contact area where the pair of fixing rolls press against each other. In a fixing device that heats and fixes an unfixed toner image on a recording sheet passing through an area, an oil application member that contacts the heating roll and applies oil for release to the surface of the heating roll; and A fixing device having an oil supply pipe disposed above and supplying oil to a lower oil application member is described. The oil supply pipe extends in a direction parallel to a contact area between the heating rotation member and the oil application member, and has an oil passage formed therein. A plurality of oil outlet holes are formed on the upper surface of the oil supply pipe at predetermined intervals along the oil flow path. The oil that has flowed out of the oil outflow hole is dropped and supplied to a lower oil application member.

[0003]

(Problem of (J01)) In the technique described in (J01), when the oil supply pipe is arranged to be inclined from the horizontal direction, it is formed on the upper surface of the oil supply pipe. The oil that has flowed out of the oil outlet hole flows along the outer peripheral surface of the oil supply pipe and flows in the axial direction. In that case, it is impossible to uniformly drop the oil on the oil application member. If the oil cannot be uniformly supplied onto the oil application member, a situation may occur in which the oil cannot be uniformly applied to the surface of the heating rotary member to which the oil is applied in contact with the oil application member. In this case, the recording paper does not peel off from the surface of the heating rotary member, so that a jam (paper jam) easily occurs. Also, unevenness in glossiness of an image is likely to occur due to uneven application of oil to the surface of the heating rotary member. Further, adhesion (offset) of unfixed toner is apt to occur on the heating rotary member in a state where the oil is insufficient, and when the toner is accumulated, black streaks and black bands are generated on copy paper.

In view of the above circumstances, the present invention provides an oil applying member that contacts the heating rotating member and applies oil for release to the surface of the heating rotating member, and the oil applying member is disposed above the oil applying member. A fixing device for an image forming apparatus having a heating rotary member and an oil supply pipe extending in a direction parallel to a contact area of the oil application member, and supplying oil for release onto the oil application member, O0
The contents described in 1) shall be the subject. (O01) To apply oil uniformly on the oil application member.

[0005]

Next, the present invention devised to solve the above-mentioned problems will be described. Elements of the present invention are used to facilitate correspondence with elements of the embodiments described later. , The reference numerals of the elements of the embodiment are enclosed in parentheses. The reason why the present invention is described in correspondence with the reference numerals of the following embodiments is to facilitate understanding of the present invention, and not to limit the scope of the present invention to the embodiments.

(The present invention) In order to solve the above problems, a fixing device for an image forming apparatus according to the present invention has the following requirements (A01) to
(A04) a heating rotary member for fixing an unfixed toner image on a recording sheet (S) passing through a fixing area (Q5) formed by pressure contact areas pressed against each other (A01). Rh) and a pressure rotating member (Rp),
(A02) The heating rotary member (Rh) disposed on the side of the recording sheet (S) where the unfixed toner image comes into contact, (A02)
03) an oil application member (17) for contacting the heating rotating member (Rh) and applying a releasing oil to the surface of the heating rotating member (Rh); (A04) the heating rotating member (Rh) and the oil; The oil application member (17) is disposed so as to extend in a direction parallel to the contact area of the application member (17), and has an oil flow path formed therein. An oil supply pipe (14) for supplying oil, wherein a plurality of oil outlet holes (14a) formed at predetermined intervals along the oil flow path;
And a plurality of axial directions provided on the outer peripheral surface of the oil supply pipe (14) to prevent the oil flowing out of the oil outlet hole (14a) from traveling in the axial direction along the outer peripheral surface of the oil supply pipe (14). The oil supply pipe (14) having a flow path blocking member (14b).

(Effect of the Present Invention) In the fixing device for an image forming apparatus of the present invention having the above configuration, the heating rotary member (R
h) and the pressure rotating member (Rp) fix the unfixed toner image on the recording sheet (S) passing through the fixing area (Q5) formed by the pressure contact areas pressed against each other. The oil application member (17) comes into contact with the heating rotary member (Rh) disposed on the side where the unfixed toner image on the recording sheet (S) contacts, and separates from the surface of the heating rotary member (Rh). Apply mold oil. The heating rotating member (Rh)
And an oil supply pipe (14) extending in a direction parallel to a contact area of the oil application member (17),
An oil flow path is formed inside, and is arranged above the oil application member (17) to supply oil to the oil application member (17) below. The plurality of axial flow path blocking members (14b) provided on the outer peripheral surface of the oil supply pipe (14) flow out of the plurality of oil outflow holes (14a) formed at predetermined intervals along the oil flow path. The transferred oil is prevented from traveling in the axial direction along the outer peripheral surface of the oil supply pipe (14). Therefore, the oil can be uniformly supplied onto the oil applying member (17).

[0008]

(Embodiment 1) Embodiment 1 of a fixing device for an image forming apparatus according to the present invention is characterized in that the present invention satisfies the following requirement (A05). (A
05) The oil supply pipe (14) in which the oil outflow holes (14a) are formed on the upper surface, and the inclined surfaces (14c) which incline downward as they move away from the oil outflow holes (14a) in the axial direction.

(Operation of the First Embodiment) In the first embodiment of the fixing device for an image forming apparatus according to the present invention having the above-described configuration, the oil supply pipe (14) has the oil outlet hole (14a). Since it is formed on the upper surface, the oil flowing through the oil supply pipe (14) does not entirely flow out of the oil outflow hole (14a) in the upstream portion, but also flows out of the oil outflow hole (14a) in the downstream side. Oil outlet (14
In order to make the oil outflow from a) uniform, it is preferable to make the upstream oil outflow hole (14a) smaller than the downstream oil outflow hole. Since the inclined surface (14c) is formed to be inclined downward as it moves away from the oil outlet holes (14a) in the axial direction, the oil flowing from the oil outlet holes (14a) flows to both sides in the axial direction. Oil can be dispersed and supplied on the application member (17).

(Examples) Next, specific examples (examples) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples. To facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left-right direction is the Y-axis direction, and the up-down direction is the Z-axis direction.
Axial direction and directions indicated by arrows X, -X, Y, -Y, Z, -Z or sides indicated are forward, rear, right, left, upper, lower, or front, rear, right, respectively. , Left side, upper side, lower side. Also, in the figure, those in which “•” is described in “○” mean an arrow pointing from the back of the paper to the front,
A mark with "x" in "o" means an arrow pointing from the front to the back of the paper.

Embodiment 1 FIG. 1 is an explanatory view of a color image forming apparatus having a fixing device for an image forming apparatus according to Embodiment 1 of the present invention. In FIG. 1, an image forming apparatus U includes an automatic document feeder U1 and a platen glass PG supporting the same.
And an image forming apparatus main body (copier) U2 having The automatic document feeder U1 includes a document feed tray TG1 on which a plurality of documents Gi to be copied are placed in an overlapping manner.
And a document discharge tray TG2 for discharging a document Gi conveyed from the document feed tray TG1 through a copy position (document reading position) on the platen glass PG. The image forming apparatus main body U2 has a UI (user interface) through which a user inputs an operation command signal such as a copy start signal, an exposure optical system A, and the like. Light reflected from a document conveyed on the platen glass PG by the automatic document feeder U1 or a document (not shown) manually placed on the platen glass PG is transmitted through the exposure optical system A through the exposure optical system A.
R (red), G (green), B (blue) for CD (solid-state image sensor)
Is converted into an electric signal. An IPS (image processing system) converts the RGB electrical signals into Y (yellow), M (magenta), C (cyan), and K (black) image data and temporarily stores the image data. Output to the laser drive circuit DL at a predetermined timing.

The surface of the image carrier (rotating member) PR which rotates in the direction of the arrow Ya is uniformly charged by the charging roll CR, and the latent image writing position Q1, the developing region Q2, and the primary transfer region Q3 are moved. Pass sequentially. The laser drive circuit DL
ROS (latent image writing device) driven by the laser beam L performs exposure scanning at the latent image writing position Q1 to form an electrostatic latent image on the surface of the image carrier PR. When a full-color image is formed, electrostatic latent images corresponding to four color images of Y (yellow), M (magenta), C (cyan), and K (black) are sequentially formed.
Only the electrostatic latent image corresponding to the (black) image is formed.

The rotary type developing device G rotates and moves to the developing area Q2 sequentially with the rotation of the rotating shaft Ga.
(Yellow), M (magenta), C (cyan), K
It has developing units GY, GM, GC, and GK for four colors (black). Each of the developing units GY, GM, GC, and GK has a developing roll GR that conveys a developer to the developing area Q2, and forms an electrostatic latent image on the image carrier PR passing through the developing area Q2. Develop into a toner image Tn.

Below the image carrier PR, a slide frame F1 is provided by a pair of left and right slide rails SR, SR.
(Indicated by a two-dot chain line) is supported so as to be slidable back and forth (in a direction perpendicular to the paper surface). Slide frame F1
Supports a belt frame F2 of the belt module BM so as to be rotatable up and down around a hinge axis F2a. The belt module BM includes a plurality of belt support rolls (Rd, Rd,
Rt, Rm, Rf, T2a) and the primary transfer roll T1
And a contact roll T2c, and the belt frame F2 that supports them. The plurality of belt support rolls (Rd, Rt, Rm, Rf, T2a) include a belt drive roll Rd, a tension roll Rt, a steering roll Rm, and an idler roll (free roll) Rf.
And a backup roll T2a, and the contact roll T2c is in contact with the backup roll T2a.

The belt module BM is rotatable up and down around the hinge axis F2a. When the belt module BM is rotated downward, the belt module BM does not come into frictional contact with the image carrier PR together with the slide frame F1 to form an image. Device body U
2 can go in and out. To the primary transfer device T1, a transfer voltage having a polarity opposite to the polarity of the charged toner is applied by a power supply circuit E controlled by a controller C.
The toner image Tn on the front surface is primarily transferred to the intermediate transfer belt B in the primary transfer area Q3. For full color images,
Toner images Tn of each color sequentially formed on the surface of image carrier PR
Are sequentially superimposed on the surface of the intermediate transfer belt B in the primary transfer area Q3, and a full-color multiple toner image is finally formed on the intermediate transfer belt B. When a monochromatic monocolor image is formed, only one developing unit is used, and the monochromatic toner image is primarily transferred onto the intermediate transfer belt B. After the primary transfer, the surface of the image carrier PR is cleaned of residual toner by the image carrier cleaner CLp, and is discharged by the discharging roller JR.

Below the backup roll T2a, a secondary transfer slide frame Fs slidable forward and backward (in a direction perpendicular to the paper surface) by a pair of left and right slide rails SR, SR with respect to the image forming apparatus main body U2. It is supported detachably. A secondary transfer lifting frame Ft of the secondary transfer unit Ut is supported on the secondary transfer slide frame Fs so as to be rotatable up and down around a hinge axis Fta. When the secondary transfer unit Ut is rotated downward, the secondary transfer unit Ut does not come into frictional contact with the belt module BM.
The user can enter and exit the image forming apparatus main body U2. 2 above
The secondary transfer unit Ut includes a secondary transfer roll T2b, a secondary transfer roll cleaner CLt, a roll support lever Lr,
Sheet guide SG2 after transfer and sheet transport belt BH
And the secondary transfer elevating frame Ft supporting them.
And

The roll support lever Lr is a lever that supports the secondary transfer roll T2b and the secondary transfer roll cleaner CLt. The roll support lever Lr is rotated around a hinge axis La by a motor (not shown) to rotate the secondary transfer roll T2b. The intermediate transfer belt B is moved between a secondary transfer position in contact with the intermediate transfer belt B and a standby position separated from the intermediate transfer belt B. A secondary transfer area Q4 is formed by the contact area between the secondary transfer roll T2b and the intermediate transfer belt B, and a secondary transfer unit T2 is formed by the secondary transfer roll T2b, the backup roll T2a, and the contact roll T2c. I have.

The recording sheets S stored in the paper feed tray TR1 are taken out by a pickup roll Rp at a predetermined timing, separated one by one by a separation roll Rs, and conveyed to a registration roll Rr. The cashier roll Rr
The recording sheet S conveyed to the pre-transfer sheet guide S is timed to move the primary-transferred multi-toner image or single-color toner image to the secondary transfer area Q4.
The sheet is conveyed from G1 to the secondary transfer area Q4. When the recording sheet S passes through the secondary transfer area Q4, a secondary transfer voltage having the same polarity as the toner charging polarity is applied to the contact roll T2c of the secondary transfer unit T2 from the power supply circuit E controlled by the controller C. Is done. The secondary transfer unit T2 collectively transfers the color toner image primarily transferred onto the intermediate transfer belt B onto the recording sheet S in the secondary transfer area Q4.
Next transfer. The residual toner is removed from the intermediate transfer belt B after the secondary transfer by the belt cleaner CLb. Further, the secondary transfer roll T2b is a secondary transfer roll cleaner CLt.
As a result, the toner adhered to the surface is collected.

The secondary transfer roller T2b and the belt cleaner CLb are disposed so as to be able to freely contact (separate and contact) with the intermediate transfer belt B, and when a color image is formed, the final color is not determined. It is separated from the intermediate transfer belt B until the applied toner image is primarily transferred to the intermediate transfer belt B. The secondary transfer roll cleaner CLt
Performs the separation / contact movement together with the secondary transfer roll T2b. The recording sheet S to which the toner image has been secondarily transferred is conveyed to a fixing area Q5 by a post-transfer sheet guide SG2 and a sheet conveying belt BH. When passing through the fixing area Q5, a heating roll (heating rotating member) Fh The sheet is heated and fixed by a fixing device F having a pair of fixing rolls constituted by pressure rolls (pressure rotating members) Fp. The recording sheet S on which the toner image has been fixed is discharged to the recording sheet discharge tray TR2. The codes Rp, Rs, Rr, SG1, SG
The sheet conveying device SH is constituted by the elements indicated by 2, BH.

(Fixing Device) FIG. 2 is a front perspective view of the fixing device according to the first embodiment, in which an oil supply shaft, an oil tank for supplying oil to the oil supply shaft, and an oil supply member are omitted. FIG. 3 is a rear perspective view of the fixing device corresponding to FIG. FIG. 4 is a front perspective view of the fixing device according to the first embodiment, from which the metering roll, the donor roll, and the external heating roll support member are omitted. FIG. 5 is a front view of FIG. FIG. 6 is a perspective view of a main part of the oil supply device for release shown in FIGS. 7 is an enlarged sectional view of the oil supply pipe shown in FIG. 6, FIG. 7A is a view showing the flow of oil when the oil supply pipe is arranged horizontally, and FIG. It is a figure which shows the flow of the oil in the case of arrange | positioning at an angle. FIG. 8 is a diagram illustrating a positional relationship between main components of the fixing device according to the first exemplary embodiment, and is a diagram illustrating a state in which a heating roll and a pressure roll are separated from each other. FIG. 9 is a diagram illustrating a positional relationship between main components of the fixing device according to the first exemplary embodiment, and is a diagram illustrating a state where a heating roll and a pressure roll are pressed against each other.

2 and 3, the heating roll Fh has a built-in heater Fha therein, and bearings Fhb, Fhb are attached to both front and rear ends (both ends in the X-axis direction). The pressure roll Fp has a built-in heater Fpa inside, and bearings Fpb, Fp are provided at both front and rear ends (both ends in the X-axis direction).
pb is installed. 2 and 3, the fixing device F
Is a horizontal base 1, vertical substrates 2F and 2R provided at both front and rear ends of the base 1, lower guide substrates 3F and 3R supported by the vertical substrates 2F and 2R, upper guide substrates 4F and 4R, and a left end, respectively. Have lifting levers 5F and 5R rotatably supported around the rotating shafts 5Fa and 5Ra. The lower guide substrates 3F and 3R have the pressure roll F
Guide grooves 6, 6 for vertically guiding the bearings Fpb, Fpb mounted on both ends of p are formed. Guide grooves 7, which guide the bearings Fhb, Fhb mounted on both ends of the heating roll Fh in the upper and lower directions, in the upper guide substrates 4F, 4R.
7 are formed.

The pair of front and rear guide grooves 7, 7 are formed so that the lower ends thereof are narrow, and regulate the downward movement of the bearings Fhb, Fhb. The guide grooves 7, 7 support the bearings Fhb, Fhb movably within a range of a vertical difference of about 2 mm.
The pair of front and rear guide grooves 6, 6 is open at the top, and the lower ends of the bearings Fpb, Fpb guided by the guide grooves 6, 6 are supported by the elevation levers 5F, 5R. Cam followers 8, 8 are rotatably supported on the free ends of the lifting levers 5F, 5R.
The position in the vertical direction can be adjusted by the rotation of the cams 9, 9 rotatably supported by F, 2R. The cams 9, 9 are integrally connected by a shaft (not shown) extending forward and backward, and are simultaneously rotated by the rotation of a pressure roll lifting motor M1 (see FIG. 3) disposed on the rear side of the vertical substrate 2R. .

When the cams 9, 9 are in the state shown in FIG. 8, the cam followers 8, 8 and the lifting levers 5F, 5R have moved to the lowered positions, and the pressure roll Fp moves downward from the heating roll Fh. Is lowered to the position In the state shown in FIG. 8, the heating roll Fh is also lowered to the lower end position of the guide grooves 7,7. In the state of FIG. 8, the distance between the heating roll Fh and the pressure roll Fp is about 2 mm. Hereinafter, the position of the heating roll Fh (down position) shown in FIG. 8 is referred to as a heating roll separation position, and the position of the pressure roll Fp (down position) shown in FIG. 8 is referred to as a pressure roll separation position. The cam 9, 9 by the pressure roll lifting motor M1
9 rotates to the state shown in FIG. 9, the cam followers 8, 8 and the lifting / lowering levers 5F, 5R have moved to the raised positions, and the pressure roll Fp is moved to the heating roll Fh.
Is pressed up from below and lifted. In the state shown in FIG. 9, the heating roll Fh has risen to the upper end position of the guide grooves 7, 7, and the pressing roll Fp has also risen to a position where it is pressed against the heating roll Fh. Hereinafter, the position (elevated position) of the heating roll Fh shown in FIG. 9 is referred to as a heated roll pressure contact position, and the position (elevated position) of the pressure roll Fp shown in FIG. 9 is referred to as a pressure roll pressure contact position.

In this embodiment, as described above, the distance that the heating roll Fh moves up and down while being guided by the guide grooves 7, 7 is about 2 mm, and the heating roll Fh in the state shown in FIG. The distance between the pressure rolls Fp is about 2 mm
It is. Therefore, when the pressure roll Fp rises about 4 mm from the state of FIG. 8, the state shown in FIG. 9 is obtained. 4 and 6, an oil tank 10 is supported on the base 1, and an oil pump 12 is supported on the oil tank 10 via a connection bracket 11. The oil for release contained in the oil tank 10 is supplied to an oil supply pipe 14 by an oil pump 12 and an oil tube 13. The oil tank 10 is configured so that an oil cartridge (not shown) for oil supply is detachably mounted.

6 and 7, the oil supply pipe 1
Reference numeral 4 denotes an integrally molded member of plastic, which extends in the front-rear direction (X-axis direction), and has a plurality of oil outlet holes 14a formed at regular intervals along the longitudinal direction on its upper surface.
The oil outlet holes 14a are formed to have a smaller diameter toward the upstream side (X side) along the oil flow path so that the amount of the oil outlet holes 14a is equalized. On the outer peripheral surface of the oil supply pipe 14, ring-shaped ribs (axial passage blocking members) 14b are formed on both sides of an oil outlet hole 14a. The rib 14b functions as an axial flow path blocking member that blocks the oil flowing out of the oil outlet hole 14a from flowing in the axial direction on the outer peripheral surface of the oil supply pipe 14. The oil flowing out from the oil outlet hole 14a flows downward or in the axial direction along the outer peripheral surface of the oil supply pipe 14, and drops downward from the position of the rib 14b. Therefore, the intervals between the ribs 14b are arranged such that the intervals between the positions where the oil is dropped are constant.

2, 3, 8, and 9, an oil pan support member 16 that supports the lower side of the oil pan 15 by vertical substrates 2 F and 2 R, and the oil that is disposed above the oil pan 15. The supply pipe 14 and the oil application member 17 are supported. The oil application member 17 is a wick that receives (drops) release oil supplied (dropped) from the oil supply pipe 14 (a flexible member having a large gap holding oil composed of a fiber bundle, a flexible foamed resin, or the like). 18, a metalling roll (oil supply roll) 19 that contacts the wick 18, and a donor roll (oil application roll) 20 that contacts the metalling roll 19 and the surface of the heating roll Fh. The metering blade 21 for regulating the amount of release oil adhering to the surface of the metering roll 19 is also provided on the vertical substrate 2.
F, 2R.

The wick 1 from the oil supply pipe 14
The releasing oil supplied to 8 is supplied to the rotating metalling roll 19, the oil on the surface of the metalling roll 19 is scraped off by the metalling blade 21 and adjusted to an appropriate amount, and the oil is supplied to the donor roll 20. From the heating roll Fh. The release oil scraped from the surface of the metalling roll 19 by the metalling blade 21 and accumulated in the oil pan 15 is returned to the oil tank 10 from an oil return tube 22 (see FIG. 6).

2 and 8, the metalling roll 19 is used.
The first swing lever 23 is supported around the rotation axis of the first swing lever 23.
A hinge shaft 23a is supported on the first swing lever 23, and a second swing lever 24 is supported by the hinge shaft 23a.
Are swingably supported. The donor roll 20 is supported by a second swing lever 24. A clockwise rotational force is constantly applied to the second swing lever 24 by a tension spring 25. With this configuration, the donor roll 20
Heating roll pressure contact position (heating roll Fh
(The position moved to the upper end of the heating roll Fh) and the metering roll 19. When the heating roll Fh moves to a heating roll separation position (a position where the heating roll Fh moves to the lower end position of the guide grooves 7, 7), the donor roll 20 separates from the heating roll Fh. The oil supply device OK is constituted by the elements indicated by the reference numerals 11 to 25.

In FIG. 8, the external heating roll device 26 has an external heating roll 27,
Bearings 28, 28 are rotatably mounted at both ends of the. On the outer surface of each bearing 28, a pair of outer flat surfaces 28a, 28a are formed on both sides of the central shaft. A heater 29 is disposed inside the external heating roll 27. In addition, the external heating roll device 26 includes a connecting member 31 extending back and forth.
(See FIG. 2) and a pair of fixed guide plates 32, 32 fixed to both front and rear ends thereof. The pair of front and rear fixed guide plates 32, 32 are upper guide substrates 4F, 4
It is fixedly supported by R. As shown in FIGS. 8 and 9, each fixed guide plate 32 has an oval guide hole 32.
a in the guide hole 32a.
Outside flat surface 28a is fitted. Therefore, the external heating roll 27 is supported by the guide hole 32a into which the outer flat surface of the bearing 28 is fitted so as to be movable away from and close to the heating roll Fh.

The outer surface of the bearing 28 is provided with a spring support 28b.
Are provided to protrude. A compression spring 33 is disposed between the spring receiver 28b and the fixed guide plate 32, and the bearing 28 and the external heating roll 27 are constantly moved toward the heating roll Fh disposed below by the compression spring 33. It receives a moving force (downward force). The downward movement of the bearing 28 and the external heating roll 27 is regulated by the lower end of the guide hole 32a, and the state shown in FIG. 8 (the state in which the heating roll Fh has moved to the heating roll separation position (down position)). Is configured to be held at a position distant from the heating roll Fh. Then, in a state where the heating roll Fh has moved to the heating roll pressing position (elevated position) (see FIG. 9), the heating roll Fh
h is pressed against the external heating roll 27. The external heating device 26 is constituted by elements indicated by the reference numerals 27 to 33.

8 and 9, the heating roll Fh
The cleaning device 36 for cleaning the surface of the printer has a web supply roll 37, a web take-up roll 38, web support rolls 39 and 40, and a web cleaning roll 41. The web 42 wound on the web supply roll 37 is guided by the outer surfaces of the web support rolls 39 and 40 and wound on the web winding roll 38.
The web cleaning roll 41 is in contact with both surfaces of the web 42 between the web support rolls 39 and 40 and the surface of the heating roll Fh. The web 42
Has a function of wiping residual oil on the surface of the heating roll Fh. The cleaning device 36 is constituted by the elements indicated by the reference numerals 37 to 42.

In FIG. 8, the pre-fixing sheet guide 43 disposed upstream of the fixing area Q5 in the sheet conveying direction.
The sheet peeling members 44 and 45 on the downstream side of the fixing area Q5 are fixed and supported by the vertical substrates 2F and 2R.

(Operation of the Embodiment) In the embodiment of the fixing device for an image forming apparatus having the above-described configuration, the pressure roll lifting motor M1 is rotationally driven to rotate the pair of front and rear cams 9, 9.
By performing position control between the separation position shown in FIG. 8 and the pressure contact position shown in FIG. 9, the pressure roll Fp can be moved between the pressure roll separation position and the pressure roll pressure contact position. . Then, by merely moving the pressure roll Fp up and down, the pressure roll Fp and the heating roll Fh are released and pressed, and at the same time, another member (donor roll 2) is pressed.
0, a member such as the external heating roll 27 and a portion of the web 42 supported on the surface of the web support roll 39) and the heating roll Fh.

During the image forming operation of the image forming apparatus U, the pressure roll Fp is moved to the pressure roll pressing position. During the image forming operation, the oil pump 12 (see FIG. 6) is operated to transfer the release oil to the oil supply pipe 14. The transferred oil flows out of the oil outlet hole 14a of the oil supply pipe 14, and
4, flows downward in the circumferential direction or in the axial direction, and drops downward from the position of the rib 14b. Since the intervals between the ribs 14b are arranged such that the intervals at which the oil is dropped are constant, a uniform amount of oil is supplied to the wick 18 along the longitudinal direction of the oil supply pipe 14 (drops). )can do. FIG. 7A is a diagram illustrating the flow of oil when the oil supply pipe is arranged horizontally, and FIG. 7B is a diagram illustrating the flow of oil when the oil supply pipe is arranged inclined from horizontal. However, in any case, a uniform amount of oil can be supplied to the wick 18 by the ring-shaped rib.

(Embodiment 2) FIG. 10 is a view showing a main part of Embodiment 2 of a fixing device for an image forming apparatus according to the present invention, and corresponds to FIG. 7 of Embodiment 1 described above. In the description of the second embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. The second embodiment is different from the first embodiment in the following point, but is otherwise the same as the first embodiment. In FIG. 10, the upper surface of the oil supply pipe 14 is formed with an inclined surface 14c which is inclined downward in the axial direction from the position of the oil outlet hole 14a. When the oil supply pipe 14 is disposed horizontally (as shown in FIG. 10A), the oil flowing out of the oil outlet hole 14a flows evenly in the axial direction by the inclined surface 14c. Oil can be supplied.

(Embodiment 3) FIG. 11 is a view showing a main part of Embodiment 3 of a fixing device for an image forming apparatus according to the present invention, and corresponds to FIG. 10 of Embodiment 2 described above. Note that the third embodiment
In the description, the same reference numerals are given to the components corresponding to the components of the second embodiment, and the detailed description thereof will be omitted. The third embodiment is different from the second embodiment in the following points.
Although the configuration is different from that of the second embodiment, the other configuration is the same as that of the second embodiment. In FIG. 11, the oil supply pipe 14
Is formed with a conical surface 14d having a small diameter along the axial direction from the position of the oil outlet hole 14a. When the oil supply pipe 14 is arranged horizontally (as shown in FIG. 11A) and when inclined from horizontal (as shown in FIG. 11A).
B), the oil that has flowed out of the oil outlet hole 14a flows evenly in the axial direction by the conical surface 14d, so that a uniform amount of oil can be supplied to the wick 18.

(Modifications) Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, but falls within the scope of the present invention described in the appended claims. Thus, various changes can be made. Modified embodiments of the present invention will be exemplified below. (H01) Instead of using a roll such as a heating roll and a pressure roll, the heating rotation member and the pressure rotation member
A rotating belt or film can be used.

[0038]

The fixing device for an image forming apparatus according to the present invention described above has the following effect (E01). (E01) Oil can be uniformly applied on the oil application member.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a color image forming apparatus having a fixing device for an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a front perspective view of the fixing device according to the first embodiment, from which an oil supply shaft, an oil tank that supplies oil to the oil supply shaft, and an oil supply member are omitted.

FIG. 3 is a rear perspective view of the fixing device corresponding to FIG. 2;

FIG. 4 is a front perspective view of the fixing device according to the first exemplary embodiment in which a metaling roll, a donor roll, and an external heating roll support member are omitted.

FIG. 5 is a front view of FIG. 4;

FIG. 6 is a perspective view of a main part of the release oil supply device shown in FIGS. 4 and 5;

7 is an enlarged cross-sectional view of the oil supply pipe shown in FIG. 6, FIG. 7A is a view showing the flow of oil when the oil supply pipe is arranged horizontally, and FIG. It is a figure which shows the flow of the oil at the time of arrange | positioning from horizontal.

FIG. 8 is a diagram illustrating a positional relationship between main components of the fixing device according to the first exemplary embodiment, and is a diagram illustrating a state in which a heating roll and a pressure roll are separated from each other.

FIG. 9 is a diagram illustrating a positional relationship of main components of the fixing device according to the first exemplary embodiment, and is a diagram illustrating a state where a heating roll and a pressure roll are pressed against each other.

FIG. 10 is a diagram illustrating a main part of a fixing device for an image forming apparatus according to a second embodiment of the present invention, and is a diagram corresponding to FIG. 7 of the first embodiment.

FIG. 11 is a diagram showing a main part of a fixing device for an image forming apparatus according to a third embodiment of the present invention.
FIG.

[Explanation of Signs] Q5: fixing area, Rh: heating rotating member (heating roll),
Rp: pressure rotating member (pressure roll), S: recording sheet,
14 ... oil supply pipe, 14a ... oil outlet hole, 14
b: axial flow path blocking member, 14c: inclined surface, 17 (18)
21) An oil application member.

Claims (2)

[Claims] 1. A fixing device for an image forming apparatus, which has the following requirements (A01) to (A04): (A01) a recording sheet passing through a fixing area formed by press-contact areas pressed against each other. A heating rotating member and a pressing rotating member for fixing the unfixed toner image on the recording sheet; (A02) the heating rotating member disposed on the side where the unfixed toner image on the recording sheet comes into contact; (A03) the heating rotating member (A04) an oil application member which is arranged to extend in a direction parallel to a contact area between the heating rotation member and the oil application member, and is provided with an oil flow therein. An oil supply pipe having a passage formed therein and arranged above the oil application member to supply oil to a lower oil application member, the oil supply pipe comprising a plurality of oil supply pipes formed at predetermined intervals along the oil flow path; A plurality of axial flow path blocking members provided on the outer peripheral surface of the oil supply pipe and the oil supply pipe to prevent oil flowing out of the oil supply hole from moving along the outer peripheral surface of the oil supply pipe in the axial direction. The oil supply pipe having: 2. The fixing device for an image forming apparatus according to claim 1, wherein the fixing device satisfies the following requirement (A05).
5) The oil supply pipe in which the oil outflow holes are formed on the upper surface, and the inclined surfaces are formed so as to be inclined downward as they move away from the oil outflow holes in the axial direction.