JP2003140482A - Heating device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate jamming disposal and to improve usability while realizing the reduction of cost by miniaturizing in particular narrowing the heating device of a film heating system and press-contact member driving type. SOLUTION: This heating device is equipped with a support 52 supporting a heating body 53, and endless and freely movable film 54 coming into contact with the heating body and the support, and a press-contact member 62 forming a nip part N by press-contacting with the heating body through the film and disposed so that the film may be driven by a driving transmission part for transmitting driving force from a driving source. In the heating device, the heat energy of the heating body is imparted to material to be heated S by holding and transporting the material to be heated S between the film and the press-contact member at the nip part, and the support 52 is fixed and supported, and the press-contact member 62 press-contacts with the heating body on the support through the film by the pressure member 111 being an elastic material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a film heating system / pressing member driving type heating device. The present invention also relates to an image forming apparatus including the heating device as an image heating unit.

[0002]

2. Description of the Related Art In a film heating type heating device, a heat resistant film is sandwiched between a heating member such as a ceramic heater and a pressure contact member to form a heating nip portion. The material to be heated is introduced between them and is nipped and conveyed together with the film, so that the material to be heated is applied to the material to be heated via the heat of the heating body in the heating nip portion. It is possible to configure an on-demand type device that has features such as quick start property and power saving by reducing the heat capacity of the heating element and the film,
For example, in an image forming apparatus such as a printer, a facsimile, and a copying machine, it can be effectively utilized as a fixing device for heating and fixing an unfixed image (unfixed toner image) formed and carried on a recording material.

An endless film (cylindrical shape, endless belt shape) is used as the film, and the film is tensionless by using a structure in which the pressure contact member is driven to rotate and the film is driven to rotate (pressure contact member drive type). As a result, it is possible to reduce the film shift movement force in the axial direction when the film is rotated, and to simplify the film shift movement control means.

FIGS. 8 to 10 show a specific example of an image heating and fixing device as a heating device of the film heating type and pressure contact member driving type as described above. 8A is a side view of the fixing device in a pressure contact state, FIG. 8B is a side view of the fixing device in a pressure contact release state, and FIG. 9 is a partially omitted / partially cutaway view of the fixing device in the pressure contact state. FIG. 10 is a vertical cross-sectional front view, and FIG. 10 is an enlarged cross-sectional model view of a main part taken along line (10)-(10) of FIG.

Reference numeral 64 denotes a fixing frame, and 58 denotes an upper frame disposed above the fixing frame 64, which can be freely opened and closed with respect to the fixing frame 64 about a fulcrum 65.

Reference numeral 62 is an elastic pressure roller as a pressure contact member, and both ends of a core metal 62A of the pressure roller are rotatably supported by bearings 63 between front and rear side plates of the fixing frame 64. It is fixedly arranged. 140 (Fig. 9)
Is a pressure roller gear fixedly attached to the end portion of the pressure roller core metal 62A. Reference numeral 141 denotes an idler gear of a drive system (not shown) which is meshed with the pressure roller gear 140.

A film guide unit (heating assembly) 50 is arranged above the pressure roller 62 in parallel with the pressure roller 62. The film guide unit 50 includes a film guide member 52 and a ceramic heater 53 as a heating body fixedly held on the lower surface of the film guide member 52 along the length of the film guide member.
A cylindrical heat-resistant film (sheet) 54 loosely fitted to the film guide member 52, a U-shaped ceramic heater stay 51 with a downward cross section inserted through the inside of the film guide member 52, and this ceramic. Outer projections 51a, 51a on the front side and the back side of the heater stay 51
3 is an assembly of the front and rear film end regulating flange members 55, 55 fitted respectively to the. The film guide member 52 holds the ceramic heater 53 and guides the movement of the film 54 from the inside. The ceramic heater stay 51 is a rigid member that reinforces the film guide member 52 from the inside, that is, the side opposite to the ceramic heater holding side.

In the film guide unit 50, with the ceramic heater 53 side facing downward, the outer projecting portions 55a and 55a of the front and rear film end regulating flange members 55 and 55 are fixed to the fixing frame, respectively. 64
The vertical guide slits 64a, 64a provided on the front and rear side plates of the fixing frame 64 are arranged so as to be vertically movable between the front and rear side plates of the fixing frame 64.

56, 56 and 57, 57 are upper frames 58.
The pressure spring and the pressure member of the upper film guide unit 50, which are arranged on the front side and the back side, respectively. Pressure member 57
Has a vertical axis portion, a pressurizing seat portion provided at a lower end portion of the vertical axis portion, and a thin neck portion provided at a lower end portion of the vertical axis portion, and the thin neck portion is provided on the upper frame 5
The upper frame 58 is supported by allowing the upper frame 58 to have a freedom of movement by inserting the hole provided in 8 from below and attaching a retaining head to the upper end of the hole. The pressure spring 56 is arranged in a compressed manner between the pressure seat of the pressure member 57 and the upper frame 58.

Reference numeral 60 denotes an upper frame closing spring, which is provided between the spring hooking portions 64b and 58b provided on the fixing frame 64 side and the upper frame 58 side on the side opposite to the fulcrum 65 side of the upper frame 58. There is.

In the free state, the upper frame 58 is closed by the pulling force of the spring 60 around the fulcrum 65 into the fixing frame 64, and as shown in FIG. It is in a state of being received by the side plate upper end portion 64c on the side. In this closed state of the upper frame, the pressure members 57.5 on the front side and the back side of the upper frame 58.
7, the pressurizing seat portions of the film guide unit 50 are front and rear side film end regulating flange members 55.5, respectively.
5 is in contact with the upper surfaces of the outwardly projecting portions 55a, 55a and is in a pressurized state by the compression reaction force of the pressure spring 56. The upper frame closing spring 60 pulls the upper frame 58 to the closing position with a force stronger than the spring pressure of the springs 56, 56 with the fulcrum 65 as the center of the pivot.

The film guide unit 50 is pressed against the upper surface of the pressure roller 62 with a predetermined pressing force by the compression reaction force of the pressure springs 56, 56, and the ceramic heater 53.
The film 54 is sandwiched between the pressure roller 62 and the pressure roller 62 to form a fixing nip portion N having a predetermined width.

The rotational force of the drive system (not shown) is applied to the idler gear 1.
41. The pressure roller 62 is transmitted to the pressure roller 62 via the pressure roller gear 140, and the pressure roller 62 is rotationally driven in the counterclockwise direction indicated by an arrow in FIG.

By the rotational driving of the pressure roller 62, a rotational force acts on the film 54 on the film guide unit 50 side in the fixing nip portion N, and the inner surface of the film 54 is the lower surface of the ceramic heater 53 in the fixing nip portion N. The outer circumference of the film guide member 52 is driven and rotated clockwise by the arrow while sliding in close contact with.

The front and rear flange members 55, 55 receive the end portions of the film on their inner surface sides, and regulate the shift of the film 54 in the axial direction as the film 54 rotates.

The ceramic heater 53 is a heater having a low heat capacity as a whole, which is basically composed of a heater substrate made of ceramics such as alumina and a conductive heating resistor pattern such as silver palladium (Ag / Pd) formed on the heater substrate surface. Is. The temperature of the energizing heating resistor pattern is rapidly raised by energizing the energizing heating resistor pattern, and the energizing circuit switches from the energizing circuit to the energizing heating resistor pattern so that the heater temperature is controlled to a predetermined fixing temperature by a temperature control circuit including a heater temperature detecting element such as a thermistor Power supply is controlled.

In FIG. 9, reference numeral 67 denotes an electric connector fitted to the front side outward projecting portion of the film guide member 52, which has a power supply terminal / temperature measuring terminal on the ceramic heater 53 side and a power supply circuit / temperature control circuit (not shown). Wiring with (lead wire)
It is electrically connected via 67a.

Then, the pressure roller 62 is rotationally driven,
Along with that, the film 54 is also driven to rotate, power is supplied to the ceramic heater 53, the heater temperature rises to a predetermined fixing temperature and the temperature is adjusted, and an unfixed toner image T is formed from the image forming unit side (not shown). The recording material S (FIG. 10) as the heated material is conveyed to the fixing device, guided by the entrance guide portion 108 and introduced between the film 54 and the pressure roller 62 in the fixing nip portion N, The part N is nipped and conveyed. The unfixed toner image T has a surface of the recording material S due to the heat applied from the heater 53 through the film 54 and the pressing force of the fixing nip portion N while the recording material S is nipped and conveyed in the fixing nip portion N. The image is fixed by heat and pressure as a permanently fixed image.

The recording material S exiting the fixing nip portion N is separated from the surface of the film 54 at the separation point, guided by the lower guide portion 107, and discharged and conveyed.

In FIG. 8, reference numeral 59 is a movable arm for releasing pressure, which is arranged so as to be rotatable about the fulcrum 66 with respect to the fixing frame 64. For some reason, the recording material S
When the apparatus stops with the fixing pin sandwiched in the fixing nip portion N, the movable arm 59 is rotated counterclockwise around the fulcrum 66 against the upper frame closing force by the pulling force of the upper frame closing spring 60. The upper frame 5 is moved by the other arm portion 59a of the movable arm 59 as shown in FIG. 8B.
8 is rotated from the fixing frame 64 about the fulcrum 65 and rotated. By the opening rotation of the upper frame 58, the pressing member 57 including the pressing spring 56, which is supported on the front side and the back side of the upper frame 58, is lifted, and the pressing member 5 is pushed.
The pressure seat portion 7 is separated from the upper surface of the outwardly projecting portions 55a and 55a of the film edge regulating flange members 55 and 55 on the front side and the rear side of the film guide unit 50. As a result, the pressure contact state of the film guide unit 50 with respect to the pressure roller 62 is released. That is, the nip pressure of the fixing nip portion N is released. As a result, the recording material sandwiched in the fixing nip portion N can be pulled out and removed.

After the recording material is removed, the movable arm 59 is returned and rotated so that the upper frame 58 is closed by the pulling force of the spring 60 with respect to the fixing frame 64 as shown in FIG. 8A. Thus, the pressure seats of the pressure members 57, 57 on the front side and the back side of the upper frame 58 correspond to the outward projecting portions 55a of the film edge regulating flange members 55, 55 on the front side and the back side of the film guide unit 50. -Abutting against the upper surface of 55a, the compression reaction force of the pressure spring 56 causes a pressure state.
That is, the film guide unit 50 is again provided with the pressure roller 6
It returns to the pressure contact state in which it is pressure-contacted with 2 and a predetermined pressing force.

[0022]

In the above-mentioned fixing device, the pressure roller 62 is fixedly arranged on the fixing frame 64 via the bearing 63, and the film guide unit 50 is movable up and down with respect to the fixing frame 64. Disposing and pressing member 56
At 57, the pressure roller 62 was pressed to form the fixing nip portion N.

However, the film guide unit 50 is
A ceramic heater 53 as a heating body is provided with a thermistor or the like (not shown) for controlling its temperature, and a connector 67 and a wire 67a for supplying electricity to the heater are also held. In the structure in which the film guide unit 50 including such an electric system member is movable, the device tends to be complicated, and since the mechanisms must be incorporated outside the width of the recording material, the device tends to be large. Met. In addition, it is more difficult to open the fixing nip portion largely for jam clearance, and a method of holding the nip pressure only as in the above example has been used. Further, when the recording material carrying the unfixed toner image during the jam processing is pulled out, the toner is easily attached to the film 54, and the processing such as cleaning is required. Since the drive is transmitted from the drive source to the side of the pressure roller 62 that is fixedly arranged, a dedicated release mechanism must be configured to release the drive, which leads to an increase in size and cost of the device. There is.

Therefore, an object of the first invention of the present application is to simplify the structure and reduce the size of the apparatus by changing the pressurizing means in this type of film heating system / pressing member driving type heating apparatus. It is an object of the present invention to provide a structure that enables a reduction in size, particularly a slimness in the width direction.

A second object of the present invention is to change the mounting structure of the pressure contact member in the heating device so that the necessary nip force is provided during normal heat treatment but weak during jam treatment. An object of the present invention is to provide a configuration in which the heated material can be easily pulled out by force.

A third object of the present invention is to change the drive releasing means in the heating device so as to provide a necessary driving force during a normal heating process, and a driving source during a jam process. It is an object of the present invention to provide a structure in which a heated material can be easily pulled out without being affected by the above.

A fourth object of the present invention is also to provide a conveying roller portion continuing from a heating nip portion of the heating device.
An object of the present invention is to provide a configuration in which a necessary nip force is provided at the time of normal transportation and a heated material can be easily pulled out by a weak force at the time of jam processing.

[0028] The fifth object of the present invention is also to provide a conveying roller portion continuing from the heating nip portion of the heating device.
By changing the drive canceling means, it is possible to provide a structure in which the material to be heated can be easily pulled out without being affected by the drive source during the jam processing, while providing a necessary driving force during the normal heat processing. That is.

An object of a sixth invention according to the present application is that in the same heating apparatus, an optimum transport path is formed in normal transport, and it is not necessary to take out a material to be heated in a narrow transport path during jam processing, It is to provide a configuration capable of securing a large jam processing area.

[0030]

The present invention is a heating device and an image forming apparatus characterized by the following configurations.

(1) A support for supporting a heating body, an endlessly movable film in contact with the heating body and the supporting body, and a nip portion formed by pressing the heating body through the film to form a nip portion. A pressure contact member arranged so that the film is driven by a drive transmission unit that transmits a drive force from the heating member by sandwiching and conveying the material to be heated between the film and the pressure contact member in the nip portion. In a heating device for applying the thermal energy of the heating body to a material to be heated, the support is fixedly supported, and the pressing member is pressed against the heating member on the support through a film by an elastic pressing member. A heating device characterized by the above.

That is, the heating member and the film-side supporting member are fixed and supported, and the pressure contact member is pressed against the heating member on the supporting member through the film by the elastic pressure member, whereby the film and heating Delicate parts such as the body can be firmly fixed, unstable elements can be reduced, the device configuration can be simplified, and the device can be miniaturized, particularly, the width can be narrowed.

(2) The pressure contact member releases the pressure contact force between the first position in which the pressure contact member is in pressure contact with the heating member through the film to sandwich and convey the material to be heated and the heating member, or the pressure contact force is weakened from the first position. The heating device according to (1), further comprising a second position.

That is, the pressure contact member can be switched between the first and second positions, and when the material to be heated is jammed, the nip portion is released by moving the pressure contact member to the second position to easily perform the jam treatment. You can

As for the fixing device, while the nip force required for the fixing process is provided, the recording material can be easily removed from the pressure contact member portion during the jam process, thereby preventing film stains and fixing nip. This is effective in improving usability during jam processing in the department.

(3) When the pressure contact member is in the first position, the drive transmission portion of the pressure contact member transmits the drive from the drive source, and when it is in the second position, the drive transmission path is disconnected. (2) The heating device as described above.

That is, the jam processing can be facilitated by cutting the drive transmission path of the pressure contact member during the jam processing.

As for the fixing device, while the driving force necessary for the fixing process is provided, in addition to that, during the jam process,
The recording material can be easily removed from the pressure contact member portion without being affected by the load from the drive source, which is effective in preventing film stains and improving usability during jam processing at the fixing nip portion.

(4) A conveying roller having a drive transmitting member for transmitting a drive from a drive source for nipping and conveying the heated material near the downstream side of the pressure contact member in the conveying direction of the heated material, and the conveying roller. A roller member that is driven by being pressed by an elastic member is provided. At the first position of the pressing member, the conveying roller and the roller member are pressed against each other or sandwich the recording material, and at the second position, the pressed state is released. Or
The heating device according to (2) or (3), characterized in that they are separated from each other.

That is, by providing a means for moving the pressing member and the conveying roller together, there is an effect that the nip of the pressing member and the nip of the conveying roller can be released with one auction during the jam processing.

As for the fixing device, the conveying roller downstream of the fixing device is provided with a necessary nip force, and apart from that, at the time of jam processing, the nip release of the pressure contact member is interlocked, so that both can be performed with one action. The nip can be released, and the recording material can be easily removed from the pressure contact member portion and the conveying roller portion, which is effective in preventing the conveying roller from being soiled and improving the usability during jam processing.

(5) A conveying roller provided with a drive transmitting member for transmitting a drive from a drive source for nipping and conveying the heated material in the vicinity of the downstream side of the pressure contact member in the conveying direction of the heated material, and the conveying roller. Is provided with a roller member that is driven by being pressed by an elastic member, and the driving force is transmitted to the conveying roller at the first position of the pressing member, and the drive transmission path is disconnected at the second position. The heating device according to (2) or (3).

That is, by providing a means for moving the drive transmission portion of the pressure contact member and the drive transmission portion of the conveying roller together,
This has the effect of enabling the drive release of the pressure contact member and the conveying roller during jam processing with one auction.

As for the fixing device, the driving force necessary for conveying the recording material is provided, and separately from that, during jam processing, the driving force of the pressure contact member is interlocked with the driving force to release both the driving forces in one action. Both the pressure contact member and the transport roller can easily remove the recording material without being affected by the load from the drive source, prevent the film and the transport roller from being soiled, and improve the usability during jam processing. Effective for improvement.

(6) A conveyance guide member which is arranged near the nip portion and guides the loading or discharging of the material to be heated into the nip portion is interlocked with the movement of the pressure contact member from the first position to the second position. Then, the heating device according to any one of (2) to (5), further comprising a transfer guide that moves to a position where the transfer path is opened.

That is, by providing a means for moving the pressure contact member and the transport guide together, there is an effect that the nip portion of the pressure contact member and the transport path opening operation can be performed with one auction during the jam processing.

Regarding the fixing device, while providing a conveyance path most suitable for conveying the recording material, in addition to that, at the time of jam processing, by interlocking with the pressure contact member, the nip of the conveyance roller, and driving, one action The effect of those loads can be removed with, the work space required for jam processing can be secured, and the contamination of the film and the transport roller can be prevented, and
It is possible to prevent damage to the transport ribs that occurs when the recording material is taken out from within the narrow transport path, and it is possible to dramatically improve usability during jam processing.

(7) The heating device according to any one of (1) to (6), wherein the material to be heated is a recording material carrying an image.

(8) In the image forming apparatus having the image forming means for forming an image on the recording material and the image heating means for heating the image on the recording material, the image heating means are (1) to (7).
An image forming apparatus, which is the heating device according to any one of 1.

[0050]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIGS. 1 to 4 are explanatory views of the structure of a heating apparatus in this embodiment. The heating device of this embodiment is a fixing device of the film heating system / pressing member driving system as in the heating device of the conventional example shown in FIGS.
The same reference numerals are given to the parts, and the repeated description will be omitted.

FIG. 1A is a side view of the fixing device in the pressure contact state, and FIG. 1B is a side view of the fixing device in the pressure contact release state.

In the fixing device 14 of the present embodiment, the film guide unit 50 is fixed to the frame of the fixing device or the frame of the image forming apparatus main body, and the pressure roller 62 side having a drive source is moved to apply pressure. By moving the roller 60, the fixing nip portion pressure release and drive release are interlocked with the movement of the roller 60.

Reference numeral 131 is an upper frame unit incorporating the film guide unit 50, and 120 is a lower frame unit incorporating a pressure roller 62 as a pressure contact member. The upper frame unit 131 is fixedly arranged as a fixed unit. The lower frame unit 120 is an oscillating unit, and the upper frame unit 13 is centered around the fulcrum 106.
It is arranged so as to be freely opened and closed and rotated with respect to the lower surface side of 1.

The film guide unit 50 has a ceramic heater 53, which is a heating body, similarly to the above-mentioned conventional apparatus.
A ceramic heater stay 51 as a reinforcing member for preventing bending in the longitudinal direction, a film 54 that comes into contact with the printing surface side of the recording material and rotates together with the recording material when the pressure roller 62 rotates, A film guide 52 that guides the rotational conveyance of the film 54 from the inside, a flange 55 that prevents the film 54 from being displaced in the longitudinal direction, and holds the film guide 52 and the ceramic heater stay 51, and the like.

In this embodiment, the film guide unit 50 is fixed to the upper frame 58 constituting the frame of the upper frame unit 131 with the screw 101 via the flange 55.

In the lower frame 105 which constitutes the frame of the lower frame unit 120, the elastic pressure roller 62 serving as a pressure contact member and the recording material S are lowered to the fixing nip portion N between the pressure roller 62 and the film guide unit 50. An entrance guide portion 108 for guiding from the side and a lower guide portion 107 for guiding the recording material after fixing are provided.

The pressure roller 62 has bearings 1 between the front and rear side plates of the lower frame 105 at both ends of the core metal 62A.
It is rotatably supported via 02. Bearing 102
Is arranged so as to be slidable in the vertical direction by being engaged with the vertical guide slit portions 103 provided on the front and rear side plates of the lower frame 105. That is, the pressure roller 62 is arranged so as to be movable in the vertical direction with respect to the frame 105. Then, the spring 1 for pressing the pressure roller 62 against the film guide unit 50 via the movable bearing 102 is provided.
11, a pressure pin 10 that supports the spring 111 and regulates its movement
4 is arranged on the lower guide frame 105.

Reference numeral 160 denotes a lower frame unit closing spring, which is provided on the upper frame 58 side and the lower guide frame 105 side on the side opposite to the rotation fulcrum 106 side of the lower frame unit 120. It has been reduced in between.

In the free state, the lower frame unit 1
20 is pulled toward the lower surface side of the upper frame unit 131 with the fulcrum 106 as the center of the pivot by the pulling force of the spring 160, and as shown in FIG.
10 is abutted against the upper frame 58 of the upper frame unit 131 and held in the closed state. In the closed state of the lower frame unit 120, the lower frame unit 120 is fixed to the upper frame unit 131 while keeping a predetermined constant distance.

In the closed state of the lower frame unit 120, the upper surface of the elastic pressure roller 62 on the lower frame unit 120 side is the upper frame unit 13.
The movable bearing 102 is attached to the downward facing ceramic heater 53 of the film guide unit 50 fixedly disposed on the first side.
The spring 111 is compressed and brought into contact with each other via. As a result, the elastic pressure roller 62 is pressed against the lower surface of the ceramic heater 53 by a predetermined pressing force with the film 54 being sandwiched by the compression reaction force of the spring 111, and the ceramic heater 53.
The film 54 is sandwiched between the pressure roller 62 and the pressure roller 62 to form a fixing nip portion N having a predetermined width.

The lower frame unit closing spring 160 has the fulcrum 106 with the fulcrum 106 as the center of the pivot.
0 is attracted to the closed position by a force stronger than the spring pressure of the springs 111 and 111.

When the apparatus is stopped while the recording material S is sandwiched in the fixing nip portion N for some reason, the lower frame unit 120 is attached to the handle portion 1 as shown in FIG. 1B.
By pressing 09 against the lower frame unit closing spring 160, the fulcrum 106 is pushed down in the counterclockwise direction of arrow E, and the upper frame unit 131 is opened and rotated. As a result, the pressure roller 62 is pushed down together, the fixing nip portion N with the film guide unit 50 is opened, and the recording material S becomes free and can be easily pulled out.

At this time, the recording material S holds an unfixed toner image on the upper surface side, and the pressure roller 62 is completely separated from the film 54 on the film guide unit 50 side, so that the unfixed image is formed on the film surface. Jam processing can be performed without pressing, and the film 54 can be prevented from being contaminated with toner.

FIG. 2 shows the structure of the drive gear transmitted to the pressure roller 62. 2A shows the arrangement of the drive gear train when the film guide unit 50 and the pressure roller 62 are in a pressure contact state as in FIG. 1A. (B)
Shows the arrangement of the drive gear train when the film guide unit 50 and the pressure roller 62 are in the pressure contact released state (during jam processing) as shown in FIG. 1B.

In FIG. 2A, the pressure roller 62 is driven by a drive source (not shown) via idler gears 142 and 141.
The drive is transmitted to the pressure roller gear 140 directly connected to the shaft 62A. This causes the pressure roller gear 140 to rotate counterclockwise and convey the recording material from right to left.

During jam processing, the frame unit 120
By pushing down the handle 109, the meshing between the idler gear 141 and the pressure roller gear 140 is released as shown in (B), and the drive transmission path is cut off.

As a result, the pressure roller gear 140 has no load at the time of rotation from the drive source, and the pressure roller 62 can be driven with a light torque. Therefore, the recording material S is weakly applied.
Therefore, it is possible to prevent the problem that the recording of thin paper, which is easily shaken, leaves fragments in the device during the jam clearance operation.

FIG. 3 is a partial sectional view showing a state in which the end portion on the drive gear side is seen from the longitudinal direction of the fixing device 14 (the direction of arrow A in FIG. 1A). A lower guide 107 provided on the lower guide frame 105 is formed in a rib-like projection shape on the partial cross section lines G to H. The film 54 is cut off in the partial cross sections H to J.
0 and the lower guide portion 10 of the lower guide frame 105
7 is cut out to show the state of the pressure roller 62.

The film guide 52 is a comb-shaped rib 52.
The sliding load during rotation is reduced by guiding the film 54 with a, and the film 54 is smoothly moved by the pressure roller 62.
Is rotated. The right side after the partial cross section J is a sectional view taken along a line passing through the axial center of the pressure roller 62 and the central axis of the screw 101 in FIG. In the film guide unit 50, the flange 55 faces the burring formed by the bent portion 58a of the upper frame 58, and the screw 10 is inserted from below.
It is fixed by 1.

Now, two different forms of the fixing method will be described with reference to FIGS. 4A and 4B in which the enlarged view of FIG.

In FIG. 4A, the ceramic heater stay 51 of FIG. 3 is extended like a 136 and directly fixed to the upper frame 58. As a result, the flange 55 can be downsized by merely abutting the end 55b against the upper frame 58. Although not shown, the film guide 5
By providing the ribs for preventing the film 54 from being thrust-shifted, it is possible to form a separate flange without any additional components.

In FIG. 4B, a ceramic heater stay 51 is provided with a bent portion 51c and a burring portion, and is fixed directly to the side surface of the upper frame 58 with a screw 101. The bent portion for fixing to the upper frame 58 is shown in FIG. Because (58a) is not attached,
The length can be shortened. Therefore, the width of the device can be narrowed in the paper width direction.

(Second Embodiment) FIGS. 5 and 6 are views for explaining the structure of the fixing device in this embodiment. The same components and parts as those of the fixing device according to the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted.

The fixing device of the present embodiment is the fixing device of the first embodiment described above, which is driven by a drive source for nipping and conveying the recording material near the downstream side of the pressure roller 62 in the recording material conveying direction. And a roller member that is driven by being pressed against the carrier roller by an elastic member.

That is, as shown in FIG. 5A, the conveying roller 16 for discharging the recording material S from the fixing device to the lower guide unit 120 side and to the downstream side of the pressure roller 62 in the recording material conveying direction.
6 is arranged in the lower guide portion 107, and the upper guide unit 1
A roller 163 is provided on the 31st side, which is pressed against the conveying roller 166 by a spring 162 held by a spring holding portion 161 of the upper guide 164 and is driven thereby.

When the conveying roller 166 becomes slower than the conveying speed of the recording material S of the pressure roller 62, the recording material S sags between the conveying roller 166 and the pressure roller 62. If the recording material immediately after the fixing process has slack, wavy wrinkling occurs. Therefore, the transport roller 166 on the downstream side of the pressure roller 62 needs to rotate at a higher peripheral speed than the pressure roller 62. Further, the pressure roller 62 is heated by the ceramic heater 53 and thermally expanded, so that the outer diameter of the roller becomes larger than that at room temperature, and the peripheral speed increases. Therefore, the transport roller 166 is set to transport the recording material at a transport speed faster than the pressure roller 62 by 4,5%.

FIG. 5B shows the state during the jam processing. Lower frame 120 with transport rollers 166
By pressing down the handle 109 in the direction of arrow E, the recording material S is released from both the nip of the pressure roller 62 and the nip of the transport roller 166.

FIG. 6A shows a drive transmission unit which is transmitted to the conveying roller 166 and the pressure roller 62 of FIG. 5A. The transport roller gear 172 that is directly connected to the shaft 166A of the transport roller 166 and rotates rotates from the idler gear 171 that meshes with the pressure roller gear 140 to the idler gear 17.
Drive is transmitted from a drive transmission path continuing to a drive source (not shown) via the drive unit 3. As a result, the transport roller gear 172 rotates counterclockwise like the pressure roller 62, and transports the recording material from right to left on the paper surface.

FIG. 6B shows the pressure roller gear 140, the conveyance roller gear 172, and the jamming roller gear 172 at the time of jam processing shown in FIG.
The idler gears 171 and 173 are arranged. During the jam processing, the conveyance roller gear 172 and the pressure roller gear 140 are disengaged from the state of FIG. 6A in association with the release of the nip by pushing down the handle 109 in the direction of arrow E. At the same time that the rotational force from the drive source is not transmitted, the reaction force received from the drive source when the transport roller gear 172 and the pressure roller gear 140 are rotated is eliminated. As a result, not only the pressure roller 62 but also the transport roller 166 can be driven, which makes jamming easier.

(Third Embodiment) FIG. 7 shows the first or second embodiment.
FIG. 3 is a schematic view of an example of an image forming apparatus including the fixing device 14 of the embodiment. The image forming apparatus of this example is a laser beam printer using a transfer type electrophotographic process.

In the laser printer 1, the video controller board (image signal creating means) 4 creates an image signal based on the information transmitted from an external information device such as a personal computer or a word processor. Here, various electronic parts installed on the video controller board 4 are not shown.

Then, the laser beam L according to the image signal generated by the video controller board 4 is irradiated onto the photosensitive drum 6A rotated by the laser scanner 5 in the clockwise direction, and the photosensitive drum 6A is sequentially electrostatically charged. Form a latent image. The photosensitive drum 6A is arranged in the process unit 6.
In the process unit 6, in addition to the photosensitive drum 6A described above,
A charging device for uniformly charging the photosensitive drum 6A to a predetermined polarity and potential, a toner developing device, a cleaning device, and the like are also provided, but they are omitted in the drawing.

Then, the electrostatic latent image formed on the photosensitive drum 6A is sequentially visualized by the toner supplied from the developing device in the process unit 6 and transferred between the photosensitive drum 6A and the transfer roller 7. Delivered to the site.

On the other hand, the recording materials S stacked and housed in the paper feeding cassette 8 are sequentially moved one by one from the uppermost recording material to the paper feeding path 10 by the half-moon-shaped paper feeding roller 9 rotating once counterclockwise. It is sent out and conveyed by the conveying roller pair 11 to the registration roller pair 12 whose rotation is stopped.

Recording material S reaching the registration roller pair 12
After hitting the nip of the recording material front end registration roller pair 12, the sheet is continuously conveyed until a predetermined loop is formed, and the skewed state is corrected.

After the correction of the skewed state is completed, the recording material S is conveyed to the transfer portion by the registration roller pair 12 which starts rotation at the timing of aligning the position with the toner image on the photosensitive drum 6A. The toner image on the photosensitive drum 6A is transferred onto the sheet surface by the roller 7.

The recording material S on which the toner image has been transferred is conveyed to the fixing device 14 through the conveyance guide 13, and here,
The transferred toner image is fixed on the sheet surface. The fixing device 14 is a heating device according to the present invention, and is, for example, the fixing device of the first or second embodiment.

The recording material S which has undergone the fixing process of the toner image is
When the printing surface is to be loaded downward, the face-down paper discharge roller 19 having a drive source (not shown) is brought into pressure contact with it through a conveyance path formed by the conveyance surface 16 and the swing guide 24 facing the conveyance surface 16. The driven roller 25 discharges the sheet onto the face-down sheet discharge tray 17 on the upper portion of the printer body 1.

When the print surface is loaded upward (face-down loading), the face-up tray 22 is opened with the rotation center 23 as a fulcrum as shown by an arrow A, and the face-up roller 18 provided with a drive source (not shown). Colo 1 driven by
5, the print surface of the recording material is discharged upward on the face-up tray 22.

(Others) 1) The heating body 53 is not limited to the ceramic heater of the embodiment, but may be, for example, an electromagnetic induction heating member.

2) The heating device of the present invention is not only an image heating and fixing device as in the embodiment, but also, for example, image heating for heating a recording material carrying an image to modify surface properties such as gloss. Device, image heating device for hypothetical dressing, heating device for feeding and heating materials such as sheet materials for drying / laminating / wrinkling treatment, heating device for drying used in inkjet printers, etc. Can be widely used.

[0092]

As described above, according to the present invention, with respect to the film heating type / pressing member driving type heating device, the jam can be eliminated while realizing the cost reduction by downsizing the device, especially by narrowing the width. It can be facilitated and usability can be improved.

[Brief description of drawings]

FIG. 1A is a side view of the fixing device according to the first embodiment in a pressure contact state, and FIG. 1B is a side view of the device in a pressure release state.

FIG. 2A is an arrangement state diagram of a pressure roller drive gear train in a pressure contact state, and FIG. 2B is an arrangement state diagram of a pressure roller drive gear train in a pressure contact release state.

FIG. 3 is a cutaway model view of one side of a fixing device in a longitudinal direction.

FIG. 4A is a diagram of a modified example of the holding unit configuration, and FIG. 4B is a diagram of another modified example of the holding unit configuration.

FIG. 5A is a side view of the fixing device according to the second embodiment in a pressure contact state, and FIG. 5B is a side view of the device in a pressure contact release state.

FIG. 6A is an arrangement state diagram of a pressure roller drive gear train in a pressure contact state, and FIG. 6B is an arrangement state diagram of a pressure roller drive gear train in a pressure contact release state.

FIG. 7 is a structural model diagram of an image forming apparatus according to a third embodiment.

FIG. 8 is a diagram showing a specific example of a fixing device as a heating device of a film heating system / pressing member driving type;
FIG. 4A is a side view of the fixing device in a pressure contact state, and FIG. 3B is a side view of the fixing device in a pressure contact release state.

FIG. 9 is a vertical sectional front view of the fixing device in a pressure contact state with a part of the fixing device omitted and a part of which is cut away.

FIG. 10 is an enlarged cross-sectional model view of a main part taken along line (10)-(10) of FIG.

[Explanation of symbols]

1 ... Printer main body device, 14 ... Fixing device, 131 ...
・ Upper frame unit, 58 ・ ・ Upper frame, 120 ・
・ Lower frame unit, 105 ・ ・ Lower guide frame 5
0 ... Film guide unit (heating assembly), 6
2 ... Pressure roller (pressing member), 51 ... Ceramic heater stay, 52 ... Film guide, 53 ... Ceramic heater, 54 ... Film, 102 ... Pressure roller bearing, 109 ... Handle , 108 ... Entrance guide, 107 ... Lower guide, 111 ... Spring, 140 ...
・ Pressure roller gear, 141 ・ ・ Idler gear, 166 ・
.Conveying rollers, 172..Conveying roller gears, N..Fixing nip portion, S..Recording material, T..Toner image

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ken Shinmura             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Yasuzumi Taba             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Hideki Miyazaki             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F term (reference) 2H033 AA21 AA37 BA25 BB28 BB33                       BB34 BB35 BB37 BB38 BE03                 3K058 AA82 AA83 AA91 AA95 BA18                       DA00

Claims (8)

[Claims] 1. A support for supporting a heating body, an endlessly movable film in contact with the heating body and the supporting body, and a nip portion formed by press-contacting the heating body via the film,
A pressure contact member arranged so that the film is driven by a drive transmission unit that transmits a drive force from a drive source,
In a heating device that applies heat energy of the heating body to the material to be heated by sandwiching and transporting the material to be heated between the film in the nip portion and the pressure contact member, the support is fixedly supported, and the pressure contact member Is pressed against the heating body on the support through a film by an elastic pressure member. 2. The pressure contact member releases the pressure contact force between the first position where the pressure contact member is in pressure contact with the heating member via the film and nips and conveys the material to be heated and the heating member, or the pressure contact force is weakened from the first position. The heating device according to claim 1, further comprising a second position. 3. The drive transmission part of the pressure contact member transmits drive from the drive source when the pressure contact member is in the first position, and the drive transmission path is disconnected when the pressure contact member is in the second position. Item 2. A heating device according to item 2. 4. A conveyance roller provided with a drive transmission member for transmitting a drive from a drive source, for nipping and conveying the heated material, in the vicinity of the heating material conveying direction downstream of the pressure contact member.
A roller member that is driven by being pressed against the conveying roller by an elastic member is provided, and the conveying roller and the roller member are in pressure contact with each other at the first position of the pressure contact member, or the recording material is sandwiched, and in the second position, the pressure contact state 4. The heating device according to claim 2, wherein the heating device is released or is separated. 5. A conveying roller provided with a drive transmitting member for transmitting a drive from a drive source, for nipping and conveying the heated material, in the vicinity of a downstream side of the pressure contacting member in the conveying direction of the heated material,
A roller member that is driven by being pressed against the conveying roller by an elastic member is provided. At the first position of the pressing member, drive is transmitted to the conveying roller, and at the second position, the drive transmission path is disconnected. The heating device according to claim 2 or 3, which is characterized in that. 6. A conveyance guide member arranged near the nip portion for guiding the heating material into or out of the nip portion, in conjunction with the movement of the pressure contact member from the first position to the second position. The heating device according to any one of claims 2 to 5, further comprising a transport guide that moves the transport path to an open position. 7. The heating device according to claim 1, wherein the material to be heated is a recording material carrying an image. 8. An image forming apparatus having an image forming means for forming an image on a recording material and an image heating means for heating an image on the recording material, wherein the image heating means is any one of claims 1 to 7. An image forming apparatus, which is the above-described heating device.