JP3875232B2 - Release agent application mechanism, fixing device, printing device - Google Patents

Description

  The present invention relates to a release agent application mechanism that applies a release agent such as oil to a fixing roller of a printing apparatus.

Usually, a printing apparatus such as a copying machine or a printer includes a fixing device for fixing a toner image transferred to a printing paper.
Such a fixing device normally performs image fixing by thermocompression bonding of a printing sheet onto which an image has been transferred with a fixing roller (roller pair).

By the way, in such a fixing device, a release agent such as silicone oil is supplied (applied) to the surface of the fixing roller. This is to prevent image transfer (image offset) to the fixing roller and wrapping of printing paper around the fixing roller in order to stably perform image fixing.
Such application of oil is described in Patent Documents 1 to 3.

14 and 15 are explanatory views showing conventional oil application techniques for the fixing roller described in Patent Documents 2-3.
As shown in these drawings, conventionally, a tubular member 105 is supplied from an oil tank 104 that can inject oil from the outside and always stores oil by a piezo-type pump (or electromagnetic pump) 103 on the upper part thereof. Oil is sucked up and supplied to the pipe member 101.

  A plurality of holes (oil discharge holes) are provided in the upper part of the pipe member 101 along the longitudinal direction thereof. Further, a felt 106 and a felt (felt for supplying a release agent) 106 for receiving oil raining down from the pipe member 101 are applied to a fixing roller (applied member) 102 below the pipe member 101. An application roller 107 is provided for this purpose.

  In addition, processing (for example, caulking processing (processing for crushing the tip with a press or the like)) for preventing oil from leaking is performed on the most downstream side (tip portion) of the pipe member 101. Oil spill from the

  Further, the excess oil remaining on the felt 106 without being applied to the fixing roller 102 is collected by a dish-shaped oil pan (release agent receiving tray) 108 formed in the lower part thereof. Then, it is returned to the oil tank 104 by a tubular member 109 connected to the oil pan 108.

A sensor 110 that detects the remaining amount of oil is installed in the oil tank 104. The sensor 110 detects the remaining amount of oil in the tank and transmits the detection result to the control unit of the printing apparatus.
As a result, when the remaining amount of oil is low, a display for prompting oil replenishment is displayed on a display panel or the like provided in the printing apparatus main body, or the printing apparatus is temporarily disabled.

  Note that when the oil supply is partially insufficient in the longitudinal direction of the fixing roller 102, the above-described image offset and printing paper wrapping occur. Accordingly, it is very important to supply the oil uniformly (balance the supply amount) in the longitudinal direction of the fixing roller 102.

  For this reason, in the above-described prior art, a plurality of holes are formed in the pipe member 101 upward (upward). Accordingly, it is possible to simultaneously discharge oil from all the holes in a state where the printing apparatus is installed horizontally (normal state).

Further, in the conventional technology as described above, only the felt and the application roller are provided as an intermediate member provided between the pipe and the fixing roller for diffusing oil in the longitudinal direction.
Therefore, when the viscosity of the oil is relatively high, the oil cannot be sufficiently diffused and may not be uniformly applied in the longitudinal direction.
For this reason, in the techniques of Patent Documents 2 and 3, a guide member is provided on the pipe member 101 so as to achieve uniformity.
JP-A-8-137317 (issue date; May 31, 1996) JP 2002-278345 A (issue date: September 27, 2002) JP 2003-122167 A (issue date; April 25, 2003)

  However, in the prior art in which oil discharged from a pipe is soaked into a guide piece (felt) to diffuse the oil, the guide piece is in close contact with the pipe. Therefore, oil can be diffused in the longitudinal direction of the pipe only by the capillary action of the guide piece. For this reason, there exists a problem that the spreading | diffusion of uniform oil cannot be performed.

  The present invention has been made in view of the conventional problems as described above. An object of the present invention is to provide a release agent coating mechanism that can uniformly apply oil to the fixing roller.

  In order to achieve the above object, a release agent application mechanism (this application mechanism) of the present invention is a release agent application mechanism that applies a release agent to a fixing roller of a printing apparatus. The release agent is discharged from a plurality of holes formed in the extending pipe, and the release agent discharged from the pipe is supplied by the release agent guide to the release agent application roller that rotates while contacting the fixing roller. In the mold application mechanism, the release agent guide is made of a material having resistance to release agents, the release agent guide extends in the longitudinal direction of the pipe with respect to the pipe, and the release agent has surface tension. It is characterized by being provided with a gap for working.

  The release agent guide as described above preferably has a first protrusion extending so as to protrude along the path of the release agent on the release agent guide.

  In this configuration, it is preferable that the first protrusion is in contact with the pipe.

  Moreover, it is preferable that the pipe is provided with the 2nd protrusion part which protrudes from the side surface of a pipe, and this 2nd protrusion part is contacting the said mold release agent guide.

  Such a configuration can be realized by using the second protrusion as a ring fitted into the pipe.

  The release agent guide is preferably in contact with the pipe by the elastic force of the release agent guide.

  Further, the release agent guide is preferably inclined with respect to the pipe at a portion where the gap is formed on the release agent guide.

  Moreover, it is preferable that the end of the release agent guide on the side close to the pipe is disposed so as to exceed a perpendicular passing through the center of the pipe.

  The fixing device according to the present invention includes the above-described main application mechanism.

  Further, the printing apparatus of the present invention has a fixing device provided with the present application mechanism.

  A release agent application mechanism (main application mechanism) of the present invention is a release agent application mechanism for applying a release agent to a fixing roller of a printing apparatus, and a plurality of holes formed in a pipe extending along the fixing roller. In the release agent application mechanism, the release agent discharged from the pipe is supplied by the release agent guide to the release agent application roller that rotates while contacting the fixing roller. The agent guide is made of a material having a release agent resistance, and the release agent guide is provided so as to extend in the longitudinal direction of the pipe with respect to the pipe and to have a gap that allows surface tension to act on the release agent. It is characterized by being.

This application mechanism applies a release agent to a fixing roller in a printing apparatus such as a copying machine or a printer.
Here, the fixing roller is a roller for fixing the image on the paper by pressing the printing paper on which the image is transferred.
The release agent is used to prevent image transfer (image offset) to the fixing roller and wrapping of the printing paper around the fixing roller. As such a release agent, for example, silicone oil can be used.

  Further, as described above, the present application mechanism has a hollow pipe extending along the fixing roller. This pipe discharges the release agent from a plurality of holes formed in itself.

Further, the present application mechanism includes a release agent application roller.
The release agent application roller is disposed along the fixing roller and rotates while being in contact with the fixing roller. The release agent application roller has a function of applying the release agent discharged from the pipe and supplied to the fixing roller to the fixing roller.

  Further, the present application mechanism includes a release agent guide (guide member) for supplying the release agent discharged from the pipe to the release agent application roller.

The release agent guide is made of a material having a release agent resistance. Here, the material having mold release resistance is a material that can avoid the penetration of the release agent (a material that does not penetrate the release agent).
Accordingly, the release agent does not penetrate into the release agent guide. As a result, the release agent guided to the release agent guide flows through the entire surface of one side (surface; the surface from which the release agent is introduced) of the release agent guide. Therefore, since the back surface of the release agent guide is not used to carry the release agent, the amount of the release agent used can be reduced. Further, since the release agent does not penetrate into the release agent guide, the speed of feeding the release agent to the release agent application roller can be increased by the release agent guide.

  In addition, when using a mold release agent guide in which the mold release agent is soaked, the mold release agent penetrates into the mold release agent guide, and the surface tension cannot be applied to the mold release agent. Further, the release agent cannot be transmitted to the release agent application roller unless a sufficient amount of the release agent is soaked into the release agent guide. For this reason, a large amount of release agent is required at the start of use of the present application mechanism (at the time of preparation for use) and it takes time to prepare for use.

  On the other hand, if a release agent guide having a release agent resistance is used, it is not necessary to soak the release agent into the release agent guide. For this reason, while being able to reduce the amount of mold release agents required for use preparation, the time for use preparation can be shortened significantly.

  And especially in this application | coating mechanism, the mold release agent guide is provided so that it may extend in the longitudinal direction of a pipe with respect to a pipe, and may have a clearance | gap so that surface tension may act on the said mold release agent. That is, a gap is formed between the pipe and the release agent guide, which extends in the longitudinal direction of the pipe so that surface tension acts on the release agent.

  For this reason, the release agent overflowing from the hole in the pipe is conveyed to the release agent guide in a state of being in contact with the pipe and the release agent guide. And the surface tension acts on the release agent led to the gap. Thereby, a mold release agent can be diffused in the direction (longitudinal direction of a pipe) where a crevice extends.

  Thereby, in this application mechanism, maintaining the state in which the release agent is diffused in the direction in which the gap extends (the surface of the release agent in which the release agent is diffused in the longitudinal direction of the pipe), It can be supplied to the release agent application roller.

  Therefore, in this application mechanism, the release agent discharged from the pipe can be uniformly supplied to the release agent application roller over its entire length (entire). As a result, it is possible to apply the oil to the entire area of the fixing roller very evenly (balance the application amount).

  In addition, by providing this application mechanism in the fixing device of the printing apparatus, it is possible to uniformly apply oil to the fixing roller, and to realize a fixing device that can satisfactorily prevent image offset and sheet winding with respect to the fixing roller. .

  The interval between the gaps varies depending on the viscosity of the release agent, the material of the release agent guide, the supply amount (supply speed) of the release agent from the pipe, and the diameter of the pipe.

The release agent guide as described above preferably has a first protrusion extending from the first protrusion extending so as to protrude along the course of the release agent on the release agent guide.
That is, the first protrusion is a partition formed on the release agent guide.
For this reason, a mold release agent will flow through the part (between 1st projection parts) partitioned off by the 1st projection part. The release agent flowing on the release agent guide does not exceed the first protrusion. Thereby, it can avoid mixing a release agent on a release agent guide. Therefore, the state in which the release agent is diffused in the longitudinal direction of the pipe described above can be maintained, and the release agent can uniformly reach the release agent application roller.

In this configuration, it is preferable that the first protrusion is in contact with the pipe.
In this configuration, the above-described gap is formed between the first protrusions that are in contact with the pipe. Accordingly, since the first protrusion is in contact with the pipe, the release agent guide can be supported by the contact portion. As a result, a gap substantially equal to the height of the first protrusion can be reliably formed between the release agent guide and the pipe. Therefore, it becomes easy to form a gap.

Moreover, it is preferable that the pipe is provided with the 2nd protrusion part which protrudes from the side surface of a pipe, and this 2nd protrusion part is contacting the said mold release agent guide.
Such a configuration can be realized by using the second protrusion as a ring fitted into the pipe.

  In this configuration, the above-described gap is formed between the second protrusions that are in contact with the release agent guide. Accordingly, since the second protrusion is in contact with the release agent guide, the release agent guide can be supported by the contact portion. As a result, a gap substantially equal to the height of the second protrusion can be reliably formed between the release agent guide and the pipe. Therefore, it becomes easy to form a gap.

The release agent guide is preferably in contact with the pipe by the elastic force of the release agent guide. In this configuration, it is not necessary to attach the release agent guide to the pipe using an adhesive or the like. For this reason, it becomes easy to assemble this application mechanism. Moreover, it is also possible to avoid that the diffusibility (uniform supply property) of the release agent is partially impaired due to the variation in the bonding part (mixed parts that are bonded and not). If there is no part, the diffusivity will fall).
Further, it is possible to prevent the release agent guide from being peeled off from the pipe due to a decrease in adhesive force during use of the present application mechanism. Furthermore, it is easy to replace the release agent guide.

Further, the release agent guide is preferably inclined with respect to the pipe at a portion where a gap is formed on the release agent guide. For example, the release agent guide is preferably inclined with respect to the pipe in a state where the release agent guide is lowered toward the application roller.
Here, the inclined state is, of course, a state that is not a horizontal state or a state of standing in the vertical (vertical) direction.

In this configuration, the release agent guide is raised from the side closer to the release agent application roller to the far side with a gap with the pipe interposed therebetween.
As a result, the oil received by the release agent guide on the side close to the release agent application roller can flow directly to the release agent application roller. On the other hand, it can be avoided that the oil received on the side far from the release agent application roller flows in a direction far from the release agent application roller (a direction away from the release agent application roller on the release agent guide).

  Moreover, it is preferable that the end of the release agent guide on the side close to the pipe is disposed so as to exceed a perpendicular passing through the center of the pipe. Here, the perpendicular passing through the center of the pipe is an imaginary straight line extending downward from the center of the pipe in the vertical direction. As a result, even if the release agent is discharged from both sides of the pipe, the release agent can be reliably guided to the release agent guide.

  Note that “close (far) to the coating member” is the closeness (distance) on the path along the release agent guide from the pipe to the coating member, and is not related to the actual distance. is there.

An embodiment of the present invention will be described.
FIG. 2 is an explanatory diagram showing the configuration of the copying machine 1, which is a digital color copying machine according to the present embodiment. The copying machine 1 has a function as a facsimile machine and a printer in addition to a function as a normal copying machine.

  First, the configuration of the copying machine 1 will be described. As shown in FIG. 2, the copying machine 1 has a configuration in which a RADF 112, a scanner unit 110, an image forming unit 210, and a paper feeding mechanism 211 are provided, and further includes an operation panel (not shown).

  The RADF 112 is a document feeding device in the copying machine 1 and has a function as a double-sided automatic document feeding device (RADF).

That is, the RADF 112 conveys a document set at a predetermined position onto a document table 111 in the scanner unit 110. Then, after the document image is read by the scanner unit 110, it has a function of carrying it out to a predetermined take-out position.
The RADF 112 also has a function of turning over the original after reading the original image by the scanner unit 110 and transporting the original to the original table 111 again. As a result, the copying machine 1 can cause the scanner unit 110 to read images on both sides of the document.

  Further, the RADF 112 can be opened and closed with respect to the document table 111. Therefore, when using the RADF 112, the user can place the document directly on the document table 111 by closing the RADF 112 and opening the RADF 112.

  The scanner unit 110 is for reading an image of a document conveyed by the RADF 112 and is an image input device in the copying machine 1. As shown in FIG. 2, the scanner unit 110 includes a first scanning unit 113, a second scanning unit 114, an optical lens 115, and a CCD 116 in addition to the document table 111 described above.

  The scanning units 113 and 114 are for reading an image of a document placed on the document table 111 by reciprocating in parallel with the document table 111.

  The first scanning unit 113 includes an exposure lamp that exposes a document image and a first mirror that deflects a reflected light image from the document in a predetermined direction. Then, it is set so as to reciprocate in parallel with the document table 111 at a predetermined scanning speed while maintaining a certain distance from the lower surface of the document table 111.

  The second scanning unit 114 includes second and third mirrors for deflecting the reflected light image deflected by the first mirror in the direction in which the optical lens 115 is positioned. The first scanning unit 113 reciprocates in parallel with the document table 111 while maintaining a constant speed relationship.

  The optical lens 115 reduces the reflected light image from the original deflected by the first to third mirrors and forms an image at a predetermined position on the CCD 116.

  A CCD (Charge Coupled Device) 116 is a photoelectric conversion element (line sensor) for photoelectrically converting the formed reflected light image to generate image information of an electrical signal and outputting it to the image forming unit 210.

  Further, the CCD 116 can read a color image. That is, the CCD 116 can generate image information of line data color-separated for each color component of R (red), G (green), and B (blue) from the color reflected light image.

  The image information generated by the CCD 116 is further transferred to an image processing unit (not shown), subjected to predetermined image processing, and then output to the image forming unit 210.

  The image forming unit 210 is for printing an image on printing paper based on the image information output from the CCD 116. The image forming unit 210 includes a black image transfer unit 301, a yellow image transfer unit 302, a magenta image transfer unit 303, and a cyan image transfer unit 304, as shown in FIG.

  These transfer units 301 to 304 have substantially the same configuration, and are set to transfer a black image, a yellow image, a magenta image, and a cyan image, respectively, to the printing paper based on the image information. ing.

  As shown in FIG. 2, these transfer units 301 to 304 have LSUs 227a to 227d and image forming stations Pa to Pd, respectively.

  Pixel signals corresponding to a black component, a yellow component, a magenta component, and a cyan component in image information are input to LSUs (laser beam scanner units) 227a to 227d, respectively. Each of the LSUs 227a to 227d is set so as to expose photosensitive drums 222a to 222d (to be described later) in the image forming stations Pa to Pd based on these image signals to generate an electrostatic latent image.

  Further, these LSUs 227a to 227d include a semiconductor laser diode (not shown) and a laser control unit that controls the power of the semiconductor laser diode and the timing of light generation in order to generate a dot-shaped laser beam modulated according to image information. And have.

  Further, as shown in FIG. 2, the LSUs 227a to 227d include polygon mirrors 240a to 240d, f-θ lenses 241a to 241d, and mirrors 242a to 242d and 243a to 243d.

  The polygon mirrors 240a to 240d have a function of deflecting a laser beam emitted from the semiconductor laser element in the main scanning direction. The f-θ lenses and mirrors described above are for imaging the laser beams deflected by the polygon mirrors 240a to 240d on the surfaces of the photosensitive drums 222a to 222d.

The image forming stations Pa to Pd generate toner images corresponding to the respective colors based on the laser beams emitted from the LSUs 227a to 227d, and sequentially transfer the toner images to the printing paper.
As shown in FIG. 2, these image forming stations Pa to Pd include photosensitive drums 222a to 222d, and further, chargers 223a to 223d, developing devices 224a to 224d, transfer dischargers 225a to 225d, and cleaning. Devices 226a to 226d are arranged around the photosensitive drums 222a to 222d along the direction of arrow F.

  Each of the photosensitive drums (transfer drums) 222a to 222d is a drum-shaped transfer roller having a photosensitive material on its surface, and is set to be rotationally driven in the direction of arrow F. The chargers 223a to 223d are for uniformly charging the photosensitive drums 222a to 222d, respectively.

  The developing devices 224a to 224d contain black, yellow, magenta, and cyan toners, respectively. These toners have a function of developing the electrostatic latent images generated on the photosensitive drums 222a to 222d to generate toner images.

The transfer dischargers 225a to 225d are dischargers for transferring the toner images on the photosensitive drums 222a to 222d to a printing sheet. The power (potential) of these transfer dischargers 225a to 225d is controlled by a power control unit (not shown).
Further, the cleaning devices 226a to 226d shown in FIG. 2 have a function of removing toner remaining on the photosensitive drums 222a to 222d after transfer onto the printing paper.

  The paper feed mechanism 211 conveys the printing paper to a predetermined position of the image forming unit 210 in order to transfer the color toner images generated by the image forming unit 210 onto the printing paper. Further, the paper feed mechanism 211 has a function of discharging the printing paper to the outside after the toner image is transferred.

  As shown in FIG. 2, the paper feed mechanism 211 includes a printing paper cassette 251, a take-out roller 253, a plurality of transport rollers 252, 261, a registration roller 212, a transfer transport belt mechanism 213, a fixing device 217, a transport direction switching gate 218, A paper discharge roller 219 and a paper discharge tray 220 are provided.

The printing paper cassette 251 is for storing printing paper P in the form of cut printing paper used in the copying machine 1.
The take-out roller 252 is a pickup roller for taking out the printing paper P from the printing paper cassette 251 one by one.
Further, the transport rollers 252... Feed the print paper P output from the print paper cassette 251 to the main transport path L and transport it on the transport path L.

  The pre-registration detection switch is for detecting that the printing paper P transported by the transport rollers 252... Has passed a predetermined position on the main transport path L and outputting a predetermined detection signal.

  The registration roller 212 temporarily holds the printing paper P that has been transported along the main transport path L. The toner image on the photoconductive drums 222a to 222d has a function of feeding it to the transfer / conveying belt mechanism 213 at the timing of each image forming station Pa to Pd so that the toner image can be satisfactorily transferred to the printing paper P. .

  That is, the registration roller 212 prints the printing paper P so that the leading edge of the toner image on the photosensitive drums 222a to 222d is pressed against the leading edge of the printing range on the printing paper P based on the detection signal output from the pre-registration detection switch. Is set to be fed into the transfer conveyance belt mechanism 213.

  As shown in FIG. 2, the transfer / conveying belt mechanism 213 includes a driving roller 214, a driven roller 215, a conveying belt 216, and an auxiliary roller 231.

  The conveyor belt 216 is a belt that is placed between the driving roller 214 and the driven roller 215, and is frictionally driven in the direction of arrow Z by the rollers 214 and 215. The printing paper P fed by the registration rollers 212 is electrostatically attracted and transported to the image forming stations Pa to Pd and the fixing device 217.

  That is, each color toner image is transferred and superimposed on the printing paper P conveyed to the image forming stations Pa to Pd. When the transfer by the image forming station Pd is completed, the printing paper P is set to be sequentially peeled off from the conveying belt 216 from the leading end portion thereof by the static eliminator 229 and guided to the fixing device 217.

The fixing device 217 heat-fixes the unfixed toner image transferred to the printing paper P. Then, the heat-fixed printing paper P is conveyed to the conveyance direction switching gate 218.
The fixing device 217 will be described later in detail.

The switching gate 218 selectively switches the transport path of the printing paper P after fixing between a discharge path toward the discharge tray 220 and the sub-transport path S.
The sub-transport path S is a transport path for turning over the printing paper P and re-supplying it to the image forming unit 210.
That is, the printing paper P sent to the sub-transport path S is turned over via the switchback transport path 221 and then transported on the sub-transport path S by the transport rollers 261... It is set to be supplied.

Next, the fixing device 217 which is a characteristic configuration of the copying machine 1 will be described in detail.
FIG. 1 is a cross-sectional view showing a configuration of a fixing device 217 having an oil application mechanism provided with a release agent guide. FIG. 3 is a perspective view showing the configuration of the fixing device 217. FIG. 4 is a front view showing the configuration of the fixing device 217.

  As shown in these drawings, the fixing device 217 includes a fixing roller pair including a fixing roller (upper fixing roller) 11 and a pressure roller (lower fixing roller) 12.

  These rollers 11 and 12 are arranged so as to be in pressure contact with each other, both of which have rubber layers 11b and 12b made of silicone rubber on the aluminum cores 11a and 12a, and inside the cores The heaters 11c and 12c including halogen lamps are provided.

  The fixing roller 11 and the pressure roller 12 both heat and press the sheet, but are given different names for convenience.

  Further, a peeling claw 13, a cleaning roller 14, and a roller temperature detector 15 are disposed around the rollers 11 and 12, respectively. Further, the fixing roller 11 is provided with an oil application roller 16.

The peeling claw 13 peels off the printing paper (recording material) wound around the rollers 11 and 12 from the surface of the rollers 11 and 12.
The cleaning roller 14 is a roller having a felt surface. The cleaning roller 14 is in sliding contact with the rollers 11 and 12 and collects offset toner attached to the surfaces of the rollers 11 and 12.
Here, the offset toner is toner that has moved to the rollers 11 and 12 from the toner image transferred to the printing paper for fixing.

  The roller temperature detector 15 is formed of a thermistor and is in contact with the surfaces of the rollers 11 and 12 to detect the temperature. The temperature detected by the roller temperature detector 15 is sent to a fixing control unit (not shown) provided in the fixing device 217.

  The fixing control unit controls the operation of the power supply unit based on the detection results of the upper and lower roller temperature detectors, and turns on / off each heater as a heat source in each fixing roller, thereby The temperature is adjusted.

Next, the oil application mechanism (main application mechanism) provided in the fixing device 217 will be described.
The present application mechanism is provided on the side and lower portions of the rollers 11 and 12, and is for uniformly applying silicone oil (release agent; hereinafter referred to as oil) to the surface of the fixing roller 11. .
The oil used in this application mechanism is a silicone oil having a kinematic viscosity at 25 ° C. of 100 cs.

  As shown in FIG. 4, in addition to the oil application roller 16, the present application mechanism includes an oil tank 21, a pump 22, a tube member 23, a guide sheet 24, a felt 25, an oil pan 26, a tube member 27, An oil sensor 28, a blade 29, and a pipe 31 are provided.

The oil tank 21 is a tank that accumulates silicone oil.
The pump 22 sucks up the oil in the oil tank 21 and can be constituted by a piezo pump or an electromagnetic pump.

  The tube member 23 is a line that supplies oil sucked from the pump 22 to the pipe 31.

  The guide sheet 24 (release agent guide) is a plate-like sheet having substantially the same length as the fixing roller 11 that extends along the fixing roller 11 along the longitudinal direction of the fixing roller 11. Here, the sheet is a thin plate that allows the release agent to flow down on the surface.

  Further, the guide sheet 24 is curved toward the oil application roller 16 in the vicinity of the pipe 31.

  The guide sheet 24 is provided so as to form a gap extending in the longitudinal direction of the pipe 31 (longitudinal direction of the fixing roller 11). That is, the guide sheet 24 is not in close contact with the pipe 31, but has a slight gap that allows oil to pass through. Note that this gap is formed between the pipe 31 and the guide sheet 24 at intervals such that surface tension acts on the oil.

  Further, the guide sheet 24 is inclined in the direction of the application roller 16 in the vicinity of the pipe 31 to facilitate oil flow.

Further, one end of the guide sheet 24 (the upstream end where the oil flows) is set so as to exceed a perpendicular line S passing through the centrality of the pipe 31.
The other end of the guide sheet 24 (the most downstream in the oil traveling direction) is provided in contact with the felt base 25a.

  The guide sheet 24 has a function of supplying the oil discharged from the hole 31 a of the pipe 31 to the felt 25 through the surface of the guide sheet 24.

  The guide sheet 24 is fixed to the support base 31 at the upstream end through which oil flows by fastening members (screws or the like) 33. The guide sheet 24 is made of a material that does not penetrate oil (oil resistance).

  The felt 25 is a plate-like felt that extends below the oil application roller 16 along the fixing roller 11 along the longitudinal direction of the fixing roller 11 and has substantially the same length as the fixing roller 11. Further, the surface of the felt 25 is in an inclined state and is set so as to contact the oil application roller 16.

The felt 25 has a function of causing the oil discharged from the pipe 31 and supplied through the guide sheet to soak into the entire surface of the felt 25 and to supply the entire surface of the oil application roller 16 described later.
The felt 25 is disposed on a felt base (application member) 25a made of a resin or metal that is slightly larger than itself. The felt base 25a is screwed to the support body 34 by a fastening member (screw or the like).

The pipe 31 is a hollow pipe having substantially the same length as the fixing roller 11 extending along the fixing roller 11 along the longitudinal direction of the fixing roller 11 (direction perpendicular to the paper surface of FIG. 4).
The pipe 31 is a hollow member having a plurality of holes 31 a provided at a predetermined interval and disposed above the application roller 16. The holes 31a are arranged side by side at the top (top) of the pipe 31 and are for discharging the oil supplied to the pipe 31.

Note that one end of the pipe 31 is connected to the tube member 23 described above and is supplied with oil. Further, although not shown, the other end portion (the most downstream side) of the pipe 31 is subjected to a caulking process (a process of crushing the tip with a press or the like) so as not to leak oil.
Therefore, all the oil supplied to the pipe 31 is discharged from the hole 31a.

The oil application roller 16 is a roller having a rubber surface, being in contact with the fixing roller 11, and extending in parallel with the fixing roller 11 and having substantially the same length as the fixing roller 11.
The oil application roller 16 has a function of supplying silicone oil from the felt 25 to the surface of the fixing roller 11 by rotating following the fixing roller 11.

  The blade 29 is a rubber-like member for uniformly extending the oil supplied to the oil application roller 16 to the surface of the roller 16 (in the form of a thin film).

A part of the oil dropped on the felt 25 is not supplied to the oil application roller 16 and falls from the felt 25 as well. Further, a part of the oil dropped on the felt 25 is not supplied to the oil application roller 16 and falls also from the discharge port 25b formed in the felt base 25a (see FIG. 6B described later).
The oil pan 26 is a dish-shaped member for receiving such oil (surplus oil) that has fallen from the felt 25.
The oil received in the oil pan 26 is returned to the oil tank 21 by the tube member 27.

  The oil sensor 28 is a sensor that is provided in the oil tank 21 and detects the remaining amount of oil in the tank 21. That is, the sensor 28 detects the remaining amount of oil in the tank 21 and transmits the detection result to the fixing control unit of the fixing device 217.

As a result, when the remaining amount of oil is low, a display prompting oil supply is displayed on a display panel or the like provided in the copying machine 1, or the copying machine 1 is temporarily disabled.
When the oil sensor 28 detects that oil has been injected into the oil tank 21, the oil sensor 28 transmits the detection result to the fixing control unit. As a result, the display or print disabled state is eliminated.

Here, the release agent guide in the present application mechanism will be described.
FIG. 1 is a cross-sectional view illustrating a configuration of a fixing device 217 having a main application mechanism including a release agent guide. FIG. 5 is a cross-sectional view showing the configuration of the guide sheet 24 and the pipe 31 in the present application mechanism. 6A and 6B are diagrams showing the configuration of the release agent guide, FIG. 6A is a development view, and FIG. 6B is a cross-sectional view. In FIG. 6A, the broken line shown in the guide sheet 24 indicates the boundary between the plan view seen from the A direction and the plan view seen from the A ′ direction in FIG. 6B. .

  As shown in these drawings, the release agent guide supplies oil discharged from the pipe 31 to the oil application roller 16. The release agent guide of the present embodiment is a guide sheet 24.

  The guide sheet 24 has a guide part 24a and a partition part 24b. Here, the guide sheet 24 is made of polyethylene terephthalate having a thickness of 0.1 mm.

  The guide part 24 a supplies oil discharged from the pipe 31 to the felt 25. In addition, the some guide part 24a is adjacent via the partition part 24b. One end portion (upstream end portion through which oil flows) of the guide portion 24 a is fixed to the support base 34 by a fastening member 33.

  The other end of the guide sheet 24 (the end on the downstream side where the oil flows) is fixed to the felt base 25 a so as to face the felt 25. This fixing is not due to the fastening member but due to the elastic force of the guide sheet 24.

The partition part (first projection part) 24b is for partitioning (partitioning) the region of the guide part 24a in the oil supply direction. A plurality of partition portions 24b are provided on the surface (surface supplying oil) of the guide sheet 24 at predetermined intervals so as to extend along the oil supply direction.
Moreover, the partition part 24b protrudes rather than the guide part 24a, is a convex part, and forms the wall between adjacent guide part 24a * 24a.

  In addition, the height of the partition part 24b should just be a grade which the oil of the guide part 24a does not move to the adjacent guide part 24a beyond the partition part 24b.

  As described above, the guide sheet 24 is in contact with the felt table 25a, and oil is supplied to the entire surface of the felt 25 through the felt table 25a.

  The felt base 25a has discharge ports 25b formed at predetermined intervals, and excess oil is collected from the discharge port 25b to the oil pan 26 described above.

Next, an oil application operation to the fixing roller 11 by the present application mechanism will be described.
In the oil application to the fixing roller 11, first, the pump 22 sucks up the oil in the oil tank 21 and supplies it to the pipe 31 through the tube member 23. The oil supplied to the pipe 31 is stored in the pipe 31 and discharged from the hole 31a when the capacity in the pipe 31 is exceeded.

  As shown in FIG. 6 (b), the oil discharged from the hole 31a falls through the outer walls on both sides of the pipe 31 (arrows in FIG. 6 (b)), and is a gap formed at the lower part of the pipe 31, The oil is uniformly diffused in the longitudinal direction of the pipe 31 and guided to the guide sheet 24.

  Then, the diffused oil maintains the diffusion state and reaches the felt 25 from the surface of the guide portion 24a of the guide sheet 24 through the felt table 25a located further downstream (downward).

  Thereafter, the oil is applied to the surface of the fixing roller 11 through the felt 25 and the oil application roller 16 (virtual circle in FIG. 6B).

As described above, in the present application mechanism, a gap is formed between the pipe 31 and the guide sheet 24 so as to extend in the longitudinal direction of the pipe 31 and to exert a surface tension on the oil.
For this reason, the oil overflowing from the hole 31 a of the pipe 31 is guided to the gap while being in contact with the guide sheet 24. And the surface tension acts on the oil led to the gap. Thereby, oil can be diffused in the direction in which the gap extends (longitudinal direction of the pipe 31).

  Thereby, in this application mechanism, it is possible to supply the oil to the oil application roller 16 while maintaining the state in which the oil is diffused in the direction in which the gap extends.

  Therefore, in this application mechanism, the oil discharged from the pipe 31 can be uniformly supplied to the application roller 16 over its entire length (entire). As a result, it is possible to apply the oil to the entire area of the fixing roller 11 in an extremely uniform manner (to balance the application amount).

The guide sheet 24 is made of a material having oil resistance. Here, the material having oil resistance refers to a material that can avoid permeation of oil (a material that does not allow permeation of oil).
Accordingly, the oil does not soak into the guide sheet 24. As a result, the oil guided to the guide sheet 24 flows through the entire surface of one side of the oil (the surface; the surface where the oil is guided). Therefore, since the back surface of the guide sheet 24 is not used for supplying oil, the amount of oil used can be reduced. Further, the speed at which the oil is fed to the felt table 25 (felt table 25a) can be increased by the guide sheet 24.

  In addition, when using the guide sheet 24 of a type that soaks oil, the oil soaks into the guide sheet 24, and the surface tension cannot be applied to the oil. Further, the oil cannot be transmitted to the felt base 25a and the felt 25 unless the guide sheet 24 is soaked with a sufficient amount of oil. For this reason, a large amount of oil is required at the start of use of the present application mechanism (at the time of preparation for use), and it takes time to prepare for use.

  On the other hand, if the oil-resistant guide sheet 24 is used, it is not necessary to soak the release agent into the guide sheet 24. For this reason, the amount of oil required for preparation for use can be reduced, and the time for preparation for use can be greatly shortened.

  Further, in the present application mechanism, one end of the guide sheet (the upstream end where the oil flows) is disposed so as to exceed the perpendicular S passing through the center of the pipe. Here, the perpendicular S passing through the center of the pipe is a virtual straight line extending downward from the center of the pipe 31 in the vertical direction. As a result, even if oil is discharged from both sides of the pipe 31, the oil can be reliably guided to the guide sheet 24.

Moreover, in this application | coating mechanism, the edge part by the side of the felt stand 25a of the guide sheet 24 (The edge part (lower end part on the downstream in the direction on which oil flows on the guide sheet 24); The edge part by the side which contacts the felt stand 25a )) Has a partition portion 24 b extending so as to protrude toward the pipe 31. That is, the partition part 24 b is a partition formed on the guide sheet 24.
For this reason, oil will flow through the part (between the partition parts 24b) partitioned by the partition part 24b. The oil flowing through the guide sheet 24 does not exceed the partition portion 24b. Thereby, mixing of oil on the guide sheet 24 can be avoided. Therefore, it is possible to maintain the state in which the oil is diffused in the longitudinal direction of the pipe 31 as described above, and to make the oil reach the felt 25 and the felt base 25a (application member) uniformly.

In the present application mechanism, the partition portion 24 b may be in contact with the pipe 31.
In this configuration, the above-described gap is formed between the partition portions 24 b and 24 b that are in contact with the pipe 31. Therefore, since the partition portion 24 b is in contact with the pipe 31, the guide sheet 24 can be supported by the contact portion. Thereby, a gap substantially equal to the height of the partition portion 24 b can be reliably formed between the guide sheet 24 and the pipe 31. Therefore, it becomes easy to form a gap.

The pipe 31 includes a protrusion 31 b protruding from the side surface of the pipe 31, and the protrusion 31 b is preferably in contact with the guide sheet 24.
Such a configuration can be realized by using the second protrusion as a ring fitted into the pipe.

  In this configuration, the above-described gap is formed in the protrusion 31 b that is in contact with the guide sheet 24. Therefore, since the protrusion 31b is in contact with the guide sheet 24, the guide sheet 24 can be supported by the contact portion. Thereby, a gap substantially equal to the height of the protruding portion 31 b can be reliably formed between the guide sheet 24 and the pipe 31. Therefore, it becomes easy to form a gap.

The guide sheet 24 is preferably in contact with the pipe 31 by the elastic force of the guide sheet 24. In this configuration, the guide sheet 24 does not need to be attached to the pipe 31 using an adhesive or the like. For this reason, it becomes easy to assemble this application mechanism. Moreover, it is also possible to avoid that the diffusibility (uniform supply property) of the oil is partially impaired due to the variation in the bonded part (mixed with the part that is bonded and the part that is not bonded) (the part that is not bonded) If there is, the diffusibility will fall).
Further, it is possible to prevent the guide sheet 24 from being peeled off from the pipe 31 due to a decrease in adhesive force during use of the present application mechanism. Furthermore, it is easy to replace the guide sheet 24.

The guide sheet 24 is preferably inclined with respect to the pipe 31 at a portion where the gap is formed. For example, it is preferable that the guide sheet 24 is inclined with respect to the pipe 31 in a state where the guide sheet 24 is lowered toward the felt base 25a.
Here, the inclined state is, of course, a state that is not a horizontal state or a state of standing in the vertical (vertical) direction.

In this configuration, the guide sheet 24 is in a state of rising from the side closer to the felt base 25a (felt 25) toward the far side with a gap with the pipe 31 interposed therebetween.
Thereby, the oil received by the guide sheet 24 on the side close to the felt table 25a (felt 25) can be directly flowed to the felt table 25a (felt 25). On the other hand, the oil received on the side far from the felt table 25a (felt 25) flows away from the felt table 25a (felt 25) (in the direction away from the felt table 25a (felt 25) on the guide sheet 24). You can avoid that.

Moreover, in this application | coating mechanism, the mold release agent guide is provided with the guide part 24a and the partition part 24b.
And the partition part 24b is extended so that it may protrude along the supply direction of oil. Thereby, it can avoid that the oil supplied to the guide part 24a mixes with the adjacent guide part 24a. Accordingly, the oil can be supplied to the felt base 25a (the application roller 16) while maintaining a uniform state guided to the guide portions 24a from the gaps.

  Moreover, in this application | coating mechanism, it can also be said that the guide sheet 24 is supported so that the said clearance gap may be formed. Thereby, the member for forming a clearance becomes unnecessary. Accordingly, the guide sheet 24 can be easily replaced.

  In the present application mechanism, the guide sheet 24 is inclined toward the application roller 16 side. Thereby, the supply of oil on the guide sheet 24 can be performed smoothly.

  In the present application mechanism, the guide sheet 24 is formed of a material that does not penetrate oil. Thereby, oil can be supplied only by the surface (one side) of the guide sheet 24. Moreover, since it is not necessary to supply oil using both surfaces of the guide sheet 24, the amount of oil can be reduced. Furthermore, it is not necessary to collect the oil that flows down the back surface of the guide sheet 24.

  In the present application mechanism, the guide sheet 24 is fixed to the support base 34 without using an adhesive. Thereby, the said clearance gap can always be kept constant and a stable oil supply is realizable.

  In addition, since this application mechanism has a small gap, even when the fixing device 217 is not used for a long time, toner, paper dust, dust, etc. floating in the copying machine 1 adhere to the hole 31a. Can be prevented.

  Further, in the present application mechanism, the guide sheet 24 having a high rigidity is used. For this reason, it becomes possible to fix to the support stand 34 by an elastic force. Accordingly, there is no need for fastening members (screws or the like) or fixing / bonding with an adhesive.

  In the present application mechanism, the guide sheet 24 is formed from a material that does not penetrate oil. Thereby, the guide part 24a supplies oil to the felt stand 25a (felt 25) using only the surface. Accordingly, the amount of oil can be reduced as compared with the case where the oil is supplied to the felt base 25a (felt 25) using both sides of the guide sheet 24.

  In the present application mechanism, a plurality of partition portions 24b are provided on the surface of the guide sheet 24 (surface for supplying oil) at predetermined intervals so as to extend along the oil supply direction. A plurality of guide portions 24a are formed at predetermined intervals. For this reason, the amount of oil supplied to the plurality of guide portions 24a is uniform. Therefore, oil can be uniformly supplied to the entire area of the felt 25.

In addition, the clearance gap formed between the guide sheet 24 and the pipe 31 can also be formed as follows. FIG. 7A to FIG. 7C and FIG. 12 are cross-sectional views showing the configurations of the guide sheet 24 and the pipe 31. 9 (a), FIG. 10 (a), FIG. 11 (a), FIG. 13 (a), and FIG. 14 (a) are developed views showing the configuration of the coating mechanism, and FIG. 9 (b). FIG. 10B and FIG. 11B are cross-sectional views. FIG. 8 is a cross-sectional view of the coating mechanism of FIGS. 7 (a), 9 (a), and 9 (b).
9 (a), FIG. 10 (a), FIG. 11 (a), FIG. 13 (a), and FIG. 14 (a), A and A ′ are the corresponding drawings as in FIG. 6 (a). The boundary of the top view in is shown.

First, in FIG. 7A, FIG. 8, FIG. 9A, and FIG. 9B, a gap is formed by the convex portion 31 b (second protrusion) formed on the pipe 31. This convex part 31b is the structure which protruded the pipe 31 itself to the side surface type | mold of the pipe 31, and the outer surface of the pipe 31, and is provided at predetermined intervals. Further, the convex portion 31 b is arranged side by side under the pipe 31. This convex part 31b can be formed by inserting a rod-shaped object from the hole 31a and applying pressure from the inside, or by compressing the pipe 31.
In addition, as shown to Fig.9 (a) and FIG.9 (b), the convex part 31b is formed directly under the hole 31a (side facing the hole 31a). And the clearance gap is formed between the lower part of the pipe 31 in which the convex part 31b is not formed, and the guide sheet 24 by making the convex part 31b and the guide sheet 24 contact.

In this coating mechanism, since the guide sheet 24 and the convex portion 32 are in contact with each other, the end portion on the pipe 31 side of the guide sheet 24 does not need to be fixed by a fastening member.
Further, another member for forming a gap between the guide sheet 24 and the pipe 31 is not necessary.

  Next, in FIGS. 7B, 10 </ b> A, and 10 </ b> B, a gap is formed by the ring 35 formed around the pipe 31. That is, a ring 35 is provided around the pipe 31 between the holes 31 a for discharging the oil in the pipe 31. The ring 35 and the guide sheet 24 are in contact with each other. As a result, the above-described gap is formed between the lower portion of the pipe 31 without the ring 35 and the guide sheet 24.

Even in this application mechanism, since the guide sheet 24 and the ring 35 are in contact with each other, the end of the guide sheet 24 on the pipe 31 side does not need to be fixed by a fastening member.
Further, the gap can be reliably formed simply by fitting the ring 35 into the pipe 31. Therefore, there is no need to process the pipe 31.

The ring 35 is an annular ring that is arranged between the two holes 31 a and 41 in the pipe 31 so as to make a round (surround) the side surface (outer wall) of the pipe 31.
The ring 35 is used to prevent the hole 31a from being blocked (the ring 35 comes into close contact with the hole 31a) and to smoothly discharge the oil from the hole 31a.

  As a material for the ring 35, PPS (polyphenylene sulfide), PET (polyethylene terephthalate), PAI (polyamideimide), PEEK (polyetheretherketone), or the like can be used. The thickness of the ring 35 may be designed according to the gap between the pipe 31 and the guide sheet 24.

Further, the ring 35 may be disposed anywhere between the two holes 31a and 31a as long as it is not on the hole 31a.
Further, it is not necessary to arrange the ring 35 between the two holes 31a and 31a. The ring 35 may be arranged in any way as long as it does not prevent oil from being discharged from the hole 31a (it is possible to avoid blocking the hole 31a with the ring 35).

  In addition, the shape of the ring 35 may be a shape in which a gap is formed between the lower portion (bottom portion) of the pipe 31 that does not have the ring 35 and the guide sheet 24 by being brought into contact with the guide sheet 24.

  Next, in FIG. 7C, FIG. 11A, and FIG. 11B, a gap is formed so that the partition portion 24 b of the guide sheet 24 reaches the pipe 31. That is, the partition portion 24b of the guide sheet 24 and the pipe 31 are in contact with each other. Thereby, the above-described gap is formed between the pipe 31 and the guide sheet 24 that is not in contact with the pipe 31.

Even in this application mechanism, since the partition portion 24b and the pipe 31 are brought into contact with each other, the end portion on the pipe 31 side of the guide sheet 24 does not need to be fixed by a fastening member or the like.
In addition, a gap can be reliably formed in the pipe 31 by the contact between the partition portion 24 b and the pipe 31. Therefore, it is easy to form a gap. Moreover, there is no need to process the pipe 31.

  In addition, what is necessary is just to make the partition part 24b contacted with the pipe 31 contact at predetermined intervals. Therefore, it is not necessary to bring all the partition portions 24b into contact with the pipe 31.

  Next, in FIG. 12, FIG. 13 (a) and FIG. 13 (b), a recess (groove) 31c formed so as to extend in the longitudinal direction of the pipe 31 at the bottom of the pipe 31 (portion facing the hole 31a). A gap is formed. That is, the partition portion 24b of the guide sheet 24 and the pipe 31 are in contact with each other. Thereby, the above-described gap is formed between the pipe 31 and the guide sheet 24 that is not in contact with the pipe 31.

In this coating mechanism, the guide sheet 24 and the pipe 31 may or may not be in contact with each other. However, when making it contact, the part in which the recessed part (groove) 31c is not formed and the guide sheet 24 are made to contact. Thereby, the recessed part 31c can be made into a clearance gap. In this case, since the guide sheet 24 and the pipe 31 are in contact, the end of the guide sheet 24 on the pipe 31 side (the end on the upstream side of the oil flow) does not need to be fixed by a fastening member or the like.
In addition, a gap can be reliably formed by contact between the guide sheet 24 and the pipe 31 (a portion where the recess 31 is not formed). Therefore, it is easy to form a gap.

  In the present embodiment, the downstream side of the guide sheet 24 in the oil flowing direction is inclined near the pipe 31 in the direction of the application roller 16 (direction of the fixing roller 11). However, the pipe 31 and the guide sheet 24 may be in a horizontal state near the pipe 31 without being inclined. This is because the oil is intermittently discharged from the pipe 31, so that the oil flows on the guide sheet 24 even when the pipe 31 and the guide sheet 24 are horizontal.

In the present embodiment, the release agent guide is formed from the guide sheet 24, the felt 25, and the felt base 25a. However, the release agent guide may be integrally configured.
For example, you may comprise integrally from the guide sheet 24 and the felt 25, without using the felt stand 25a.

  In the present embodiment, oil is applied to the fixing roller 11 of the fixing device 217 by the application mechanism. However, the present invention is not limited to this, and the oil application roller 16 may be brought into contact with the pressure roller 12 which is the other fixing roller to apply the oil to the pressure roller 12. Further, oil may be applied to both the rollers 11 and 12.

  In the present embodiment, silicone oil is used as the release agent. However, this application mechanism is not limited to silicone oil, and any other release agent can be used. Moreover, as a mold release agent, the thing of 100-300cs can generally be used. For example, a silicone oil having a kinematic viscosity at 25 ° C. of 100 cs can be used as the release agent. Silicone oil having a kinematic viscosity of less than 100 cs is dangerous for use in a fixing device because of its low flash point. Also, silicone oil having a kinematic viscosity exceeding 300 cs is difficult to supply with a piezo-type or solenoid-type pump.

  In the present embodiment, the oil application roller 16 is rotated by following the fixing roller 11. However, the present invention is not limited to this, and the oil application roller 16 may be set to rotate by a driving mechanism different from the fixing roller 11. The rotation direction of the oil application roller 16 may be the same direction as the fixing roller 11 or the opposite direction.

  Moreover, in this Embodiment, it is supposed that the felt 25 is provided in this application | coating mechanism. However, the felt 25 may not be provided, and the oil may be designed to be supplied from the guide sheet 24 directly to the oil application roller 16 or via the felt base 25a.

  Further, the felt 25 (oil supply felt) for supplying oil in contact with the oil application roller 16 may be formed of heat-resistant nomex felt. In this case, the felt 25 having a thickness of about 1 mm to 5 mm can be used. The oil supply felt 25 is affixed to an elastic felt base 25a (support member; formed from a stainless steel plate having a thickness of 0.2 mm) and expressed as being biased toward the oil application roller 16. You can also.

  Moreover, you may form the guide sheet 24 from the material which has heat resistance in the said embodiment. In this case, a thin guide sheet 24 having a thickness of about 0.025 mm to 0.25 mm can be used. However, although depending on the material of the guide sheet 24, if it is too thin, the guide member is likely to be damaged at the time of assembly in the factory, and the elastic force is lowered.

The material of the guide sheet 24 is preferably a material that can be formed thin, such as plastic or metal. As the guide sheet 24, any material can be used as long as it is formed of a material having heat resistance (about 200 ° C.) and oil resistance. For example, a metal plate such as polyimide, polyethylene terephthalate, polyamide or stainless steel plate can be used.
Further, the guide sheet 24 needs to be made of a material that does not allow the oil overflowing from the pipe 31 (pipe member) to permeate. This is because a slight gap formed between the guide sheet 24 and the pipe 31 (a gap extending in the longitudinal direction of the pipe 31) is used to diffuse the oil in the longitudinal direction of the pipe 31 by utilizing surface tension acting on the oil. It is because it comprises.

  Further, when a material having oil permeability, such as felt, is used for the guide sheet 24, the capillary phenomenon almost occurs only in the guide sheet 24. Further, oil soaks into the guide sheet 24. For this reason, surface tension can hardly be applied to the oil. For this reason, if the diffusibility in the longitudinal direction of the guide sheet 24 is reduced, the oil stays inside the felt 25 and the release agent is liable to deteriorate or the flow rate of the release agent must be increased. It is not preferable because it becomes an economy.

  Further, if a material having low rigidity, in other words, an elastic material is used as the material of the guide sheet 24, for example, if a film or a metal thin plate is used as the material of the guide sheet 24, the elasticity of the film member or the metal thin plate is improved. The guide sheet 24 is fixed to the support base (base) 34 with a fastening member such as a screw so that the guide sheet 24 is urged toward the pipe 31. At this time, since the guide sheet 24 and the pipe 31 are not bonded by an adhesive or the like, the oil overflowing on the opposite side of the pipe 31 also oozes out from the gap formed by the pipe 31 and the guide sheet 24. . Then, the oil is guided toward the fixing roller 11 as the supply target through the oil application roller 16 by the inclination of the guide sheet 24.

  The slight gap formed between the guide sheet 24 and the pipe 31 is preferably about 0.5 mm to 1 mm. This is because the oil can be diffused in the longitudinal direction of the pipe 31 by a capillary phenomenon without clogging with paper dust or dust.

  Note that the gap is formed between the pipe 31 and the guide sheet 24, and needs only to have a size that extends in the longitudinal direction of the pipe 31 so that surface tension acts on the oil. The “gap with which the surface tension works” means that oil discharged from the pipe 31 is conveyed to the guide sheet 24 while being in contact with the guide sheet 24 and the pipe 31 and the pipe 31 in this gap A gap that allows oil to diffuse is shown in the longitudinal direction.

  The length (interval) of the gap varies depending on the type of oil, the viscosity of the oil, the material of the guide sheet 24, the amount of oil supplied from the pipe 31 to the gap (supply speed), the diameter of the pipe 31, and the like. .

  Moreover, the convex part (2nd projection part) 31b provided in the pipe 31 uses the hole 31a to partially protrude and deform the outer wall, or grip the pipe 31 and compress the pipe 31 in the longitudinal direction. Or by attaching a ring 35 to the outer wall. Conversely, the bottom surface (lower side) of the pipe 31 may be dented, and a gap with the guide portion 24a of the guide sheet 24 may be provided by a groove (concave portion) from the bottom surface of the pipe 31 toward the inside.

  As a method of providing a gap between the guide portion 24 a of the guide sheet 24 and the pipe 31, the partition portion (first protrusion) 24 b provided on the guide sheet 24 is partially extended so as to contact the pipe 31. A gap may be provided.

  Further, when a material having high rigidity, such as a stainless steel plate, is used as the material of the guide sheet 24, the guide sheet 24 can be fixed to the support member so that a slight gap is formed without crafting the pipe 31.

  Further, the guide sheet 24 may be formed from a thin steel plate or plastic (film or thin molded product). Thus, when the gap is formed by bringing the pipe 31 and the guide sheet 24 into contact with each other, the guide sheet 24 can be reliably brought into contact with the pipe 31 by using the elastic force of the guide sheet 24. In this case, for example, the guide sheet 24 may be urged toward the pipe 31 and fixed to the support base 34 using a fastening member such as a screw.

  Further, since the guide sheet 24 is not attached to the pipe 31 using an adhesive or the like, it is easy to assemble. Further, the contact state between the guide sheet 24 and the pipe 31 does not become unstable due to variations in the amount of adhesive used. Therefore, the state of oil diffusion in the gap (a state where oil is supplied uniformly) due to poor adhesion is not partially damaged. Further, the guide sheet 24 does not peel off during use of the present application mechanism. Furthermore, only the guide sheet 24 can be easily replaced.

  Further, the partition portion 24b of the guide sheet 24 can be formed by pressing when the guide sheet 24 is metal, or by molding when the guide sheet 24 is plastic. The height of the dividing portion 24b is preferably 0.5 mm to 1 mm.

Further, as described above, a piezo-type pump or an electromagnetic pump can be used as the pump 22 of the coating mechanism.
Piezo-type pumps operate at the frequency of an AC power source, and are more expensive (about twice the price of an electromagnetic pump) than an electromagnetic pump driven by a DC power source. For this reason, it is also preferable to use an inexpensive electromagnetic pump.

As an electromagnetic pump constituting the pump 22 of the coating mechanism, one that can be driven by a DC pulsed current (a pulse current having a period of 30 ms to 300 ms and a pulse width of 3 ms to 50 ms) can be used.
Further, the flow rate of such an electromagnetic pump can be adjusted to 1 to 10 cc / min. By adjusting the pulse width and period of the supplied pulse current. Can be set within the range.

Conventionally, since a permeable (penetrating mold release agent) guide member has been used, the flow rate of the electromagnetic pump described above is 4 to 5 cc / min. Was supplied at a flow rate of. This is because the release agent is supplied by using both surfaces of the guide member.
On the other hand, in the present invention, since a guide member that is not permeable (the mold release agent does not penetrate) is used, the flow rate of the electromagnetic pump is set to 2 to 3 cc / min. It is possible to reduce it. This is because the mold release agent is supplied using only the surface (one side) of the guide member.

In the present embodiment, the laser writing units 227a to 227d scan and expose a laser beam to perform optical writing on the photosensitive member. However, the present invention is not limited to this, and instead of the laser writing units 227a to 227d, a solid scanning writing optical system (LED head) including a light emitting diode array and an imaging lens array may be used.
The LED head is smaller than the laser writing units 227a to 227d and has no moving parts and is silent. Therefore, it can be suitably used for an image forming apparatus such as a tandem digital color copying machine that requires a plurality of optical writing units such as the copying machine 1.

  Further, the release agent application method of the present invention is a release agent application method for applying a release agent to a fixing roller of a printing apparatus, wherein the release agent is released from a plurality of holes formed in a pipe extending along the fixing roller. A discharge step of discharging the agent, and a supply step of supplying the release agent discharged from the pipe with a release agent guide to the release agent application roller that rotates while being in contact with the fixing roller. The guide has a curved portion curved in the direction of the release agent application roller along the pipe in the vicinity of the pipe, and the release agent discharged from the hole of the pipe is applied to the release agent through the curved portion. It can also be expressed that the method is set to supply to the roller.

  Moreover, it can be said that the ring 35 shown in FIG.7 (b) etc. is a ring provided so that the outer peripheral surface of the pipe 31 might be made a round in the direction orthogonal to the axis | shaft (longitudinal direction) of the pipe 31. FIG. Instead of providing such a ring 35, the pipe 31 may be directly processed to form a protrusion. That is, in the present embodiment, the ring 35 which is a member different from the pipe 31 is used. However, if the pipe 31 itself is processed, the same shape can be obtained without using the ring 35. Obtainable.

  Further, conventionally, a release agent (silicone oil or the like) that overflows and drops from a plurality of holes of a release agent supply pipe member is dropped near a member to be coated (a fixing roller or a pressure roller). Therefore, the viscosity of the release agent is relatively high although it is through an intermediate member (release agent application roller or release agent supply felt) that supplies the release agent in contact with the member to be applied. It can be said that there is a problem that the toner cannot be sufficiently diffused and the release agent supply in the longitudinal direction is not uniform, and a good toner image cannot be fixed on the paper.

  Another object of the present invention is to provide a guide member between a release agent application member that supplies a release agent in contact with a member to be applied and the pipe member, and the release agent is provided between the guide member and the pipe member. A release agent supply device that, after being diffused, guides the release agent by a guide member, and enables uniform application of the release agent to the fixing roller and pressure roller that are to be applied. It can be said that there is provided a fixing device provided with a release agent supply device capable of supplying uniformly to a member to be coated without using a guide member without using a guide member and an image forming apparatus provided with the fixing device.

The method for supplying silicone oil to the application roller for applying silicone oil to the fixing roller 11 in the fixing device shown in FIG. 4 may be expressed as follows. That is, oil is injected into an injectable oil tank 21 provided from the outside (both in the fixing device and outside) provided in the lower portion of the fixing device. A tube-shaped member 23 is used from a piezo-type or electromagnetic pump 22 and is connected to a pipe 31 having a plurality of holes in order to enable uniform oil supply in the longitudinal direction of the fixing roller 11.
The oil overflowing from the plurality of holes descends along the wall surface of the pipe 31 and is disposed below the pipe 31 with a slight gap between the guide portion (guide portion 24a) and the guide member (guide). It is diffused by capillarity in the gap formed by the sheet 24). The guide member has a slight inclination, and the oil further descends due to the inclination, and the oil is uniformly supplied to the oil supply felt (felt 25) pressed against the oil application roller 16. The most downstream of the pipe 31 is treated so that oil does not leak (in this case, caulking (crushing the tip with a press or the like) is performed, so that oil is not discharged from other than a plurality of holes. .

  The oil supplied to the oil supply felt 25 once soaks into the oil supply felt 25 and is supplied to the oil application roller 16 via the oil supply felt 25. The oil supplied to the application roller 16 is further made uniform by an application blade (blade 29) made of a rubber member so that a uniform amount of oil can be applied onto the surface of the fixing roller 11 on the thin film. In addition, surplus oil that has not been used for oil application by the supply means is collected by the oil pan 26, a dish-like member installed under the application roller 16 and felt (oil supply felt) 25 from the discharge port 25b and the like. Then, it is returned to the oil bottle (resin layer 21) by a tubular member 27 connected to the oil pan 26. The above system circulates oil in the oil supply and coating device (coating mechanism), and detects the remaining amount of oil installed in the oil tank 21 when the amount of oil required for circulation in the oil bottle is likely to be insufficient. The sensor 28 detects the situation and prompts the user to replenish oil with an operation panel or the like provided in the image forming apparatus. Alternatively, it is possible to temporarily control the machine to an unusable state. In this case, it is possible to perform control that enables normal operation when oil is injected.

  The present invention can also be expressed as the following first to seventh release agent supply devices, first fixing devices, and first image forming devices. In other words, the first release agent supply device is a release agent supply device that supplies a release agent to a fixing device having a fixing unit including a rotating fixing roller and a pressure roller in pressure contact with the fixing roller. An intermediate guide means is provided by allowing a release agent supplied from a release agent supply pump to overflow from the plurality of holes from a cylindrical body disposed on the top of the roller and provided with a plurality of holes in the axial direction of the upper surface. In the release agent supply device that supplies the release agent to at least one of the fixing roller and the pressure roller via the guide member, the release agent diffuses between the guide member forming the intermediate guide means and the cylindrical body. The guide member is arranged with respect to the cylindrical body so that the release agent is supplied while maintaining the diffusion state. According to this configuration, when the release agent is supplied to the supply target via the guide member, the release member is spread over a wide range by the guide member, and the function of guiding the release agent can be maintained. In order to further increase, the release agent can be diffused on the most upstream side by the capillary phenomenon generated between the cylindrical body and the guide member, and then guided while maintaining the state. The agent can be uniformly supplied to the supply target, and a good fixing function can be maintained.

  Further, the second release agent supply device is the first release agent supply device, wherein the guide member has a guide portion and a partition portion, and the partition portion is provided on the guide portion side of the release agent. The guide member is arranged with respect to the cylindrical body so that a slight gap is formed with respect to the cylindrical body. According to this configuration, by providing a slight gap between the guide portion of the guide member and the cylindrical body, a capillary phenomenon works between the cylindrical body and the guide portion of the guide member, and the guide portion is released from the mold. The diffused release agent can be guided while maintaining the state by the partition portion provided on the guide portion side where the agent can be diffused.

  Further, the third release agent supply device is the second release agent supply device, wherein the gap between the cylindrical body and the guide portion of the guide member is such that the partition member of the guide member is brought into contact with the cylindrical body and the guide member. It is the structure formed by positioning. According to this configuration, by bringing the partition portion of the guide member into contact with the cylindrical body, a predetermined gap can be formed and a good capillary phenomenon can be obtained, and the release agent can be diffused into the guide portion of the guide member. it can. Further, the fourth release agent supply device is the second release agent supply device, wherein the gap between the cylindrical body and the guide portion of the guide member is formed on the convex portion formed on the surface of the cylindrical body. It is the structure formed by making a guide part contact and positioning a guide member. According to this configuration, by bringing the guide portion of the guide member into contact with the convex portion of the cylindrical body, a predetermined gap is created and a good capillary phenomenon can be obtained, and the release agent is diffused into the guide portion of the guide member. Can be made.

  Further, the fifth release agent supply device is configured such that in the third or fourth release agent supply device, the guide member contacts the cylindrical body by the elastic force of the guide member. According to this configuration, by utilizing the elastic force of the guide member itself, the predetermined gap can be provided between the guide portion of the guide member and the cylindrical body and can be reliably positioned. Moreover, the 6th mold release agent supply apparatus WHEREIN: In any one of the 1st-5th mold release agent supply apparatuses, the said guide member is located with respect to the cylinder state in the state inclined in the lower side of the cylindrical body. It is a configuration. According to this configuration, the guide member is disposed on the lower side of the cylindrical body and is inclined so that the release agent overflowing from the hole in the upper portion of the cylindrical body is received by the guide member and the capillary phenomenon occurs. Can be diffused and the release agent can be guided toward the supply target.

  Further, in the seventh release agent supply device, in any one of the first to sixth release agent supply devices, the guide member is formed of a material that does not penetrate the release agent, and the release member is formed on the surface of the guide member. In this configuration, the release agent is guided and supplied to the supply object by transmitting the agent. According to this configuration, since the guide member is formed of a material that does not allow the release agent to permeate, it is possible to obtain a good capillary phenomenon with the cylindrical body, and to diffuse the release agent well. In addition, the amount of the release agent supplied can be reduced by preventing the release agent from penetrating into the guide member. Further, workability at the time of exchanging the guide member is improved, and the loss of the release agent due to the exchange can be reduced. The first fixing device is a fixing device having a rotating fixing roller and a fixing unit composed of a pressure roller that is in pressure contact with the fixing roller. The first fixing device is disposed above the fixing roller and has a plurality of holes in the axial direction on the upper surface. The release agent supplied from the release agent supply pump is caused to overflow from the plurality of holes from the cylindrical body provided with the intermediate member, and is supplied to at least one of the fixing roller and the pressure roller. In the fixing device including the release agent supply device to be supplied, any one of the first to seventh release agent supply devices is provided. According to this configuration, the above-described effect can be obtained in the fixing device. Further, the first image forming apparatus has a first fixing device. According to this configuration, by providing the fixing device in the image forming apparatus, it is possible to obtain the above effects and perform good image formation.

  The release agent application mechanism according to the present invention can supply the release agent uniformly to the fixing roller by the release agent guide. Therefore, the present application mechanism can be applied to various image forming apparatuses having a fixing device such as a copying machine.

1 is a cross-sectional view illustrating a configuration of a fixing device having an oil application mechanism including a release agent guide according to an embodiment of the present invention. It is explanatory drawing which shows the structure of a digital color copying machine which has a fixing device provided with the oil application | coating mechanism shown in FIG. FIG. 3 is a perspective view showing a configuration of a fixing device provided in the digital color copying machine shown in FIG. 2 and having the oil application mechanism shown in FIG. 1. FIG. 3 is a front view showing a configuration of a fixing device provided in the digital color copying machine shown in FIG. 2 and having the oil application mechanism shown in FIG. 1. It is sectional drawing which shows the structure of the mold release agent guide shown in FIG. It is a figure which shows the structure of the mold release agent guide shown in FIG. 1, FIG. 6 (a) is an expanded view, FIG.6 (b) is sectional drawing. Fig.7 (a)-FIG.7 (c) are sectional drawings which show the other structure of the mold release agent guide in the oil application mechanism concerning one Embodiment of this invention. It is sectional drawing which shows the structure of the mold release agent guide of Fig.7 (a). It is a figure which shows the structure of the mold release agent guide shown to Fig.7 (a) and FIG. 8, FIG. 9 (a) is an expanded view, FIG.9 (b) is sectional drawing. It is a figure which shows the structure of the mold release agent guide shown in FIG.7 (b), Fig.10 (a) is an expanded view, FIG.10 (b) is sectional drawing. It is a figure which shows the structure of the mold release agent guide shown in FIG.7 (c), FIG.11 (a) is an expanded view, FIG.11 (b) is sectional drawing. It is sectional drawing which shows the other structure of the mold release agent guide in the oil application mechanism concerning one Embodiment of this invention. FIG. 13 is a diagram showing a configuration of the release agent guide shown in FIG. 12, FIG. 13A is a development view, and FIG. 13B is a cross-sectional view. It is explanatory drawing which shows the conventional oil application technique. It is explanatory drawing which shows the conventional oil application technique.

Explanation of symbols

1 Copying machine (printing device)
DESCRIPTION OF SYMBOLS 11 Fixing roller 12 Pressure roller 13 Peeling claw 14 Cleaning roller 15 Roller temperature detector 16 Oil application roller 21 Oil tank 22 Pump 23 Tube member 24 Guide sheet 24a Guide part 24b Partition part (1st projection part)
25 Felt (Coating material)
25a Felt stand (coating material)
26 Oil pan 27 Tube member 28 Oil sensor 29 Blade 31 Pipe 31a Hole 31b Projection (second projection)
35 Ring (second protrusion)
217 Fixing device

Claims (10)

In order to apply the release agent to the fixing roller of the printing device ,
The release agent is discharged from the plurality of holes formed in the pipe extending along the fixing roller,
In a release agent application mechanism that supplies a release agent discharged from the pipe with a release agent guide to a release agent application roller that rotates while contacting the fixing roller.
The release agent guide, extending in the longitudinal direction of the pipe, and provided so as to have a gap between the pipe and the releasing agent guide,
A release agent application mechanism configured to diffuse the release agent in the longitudinal direction of the pipe in the release agent guide by capillary action in the gap . 2. The release agent application according to claim 1, wherein the release agent guide has a first protrusion extending so as to protrude along a path of the release agent on the release agent guide. Mechanism . Said first protrusion, the release agent coating mechanism according to claim 2, characterized in that in contact with the pipe. The pipe is provided with a second protrusion protruding from the side surface of the pipe,
The mold release agent application mechanism according to claim 3, wherein the second protrusion is in contact with the mold release agent guide. The mold release agent application mechanism according to claim 4, wherein the second protrusion is a ring fitted into the pipe. The release agent guide, by the elastic force of the releasing agent guide, release agent coating mechanism according to claim 3, characterized in that in contact with the pipe.   The release agent application mechanism according to claim 1, wherein the release agent guide is inclined with respect to the pipe at a portion where the gap is formed on the release agent guide. End of the releasing agent guide, the release agent coating mechanism according to claim 1, characterized in that it is arranged to exceed the vertical line passing through the center of the pipe.   A fixing device comprising the release agent application mechanism according to claim 1.   A printing apparatus comprising the fixing device according to claim 9.

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