JP7644902B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus .

Conventionally, image forming apparatuses have been known that include a fixing device that fixes an image onto a recording material and an exhaust duct that exhausts gas from within the fixing device.

For example, Patent Document 1 discloses an image forming apparatus in which a filter member capable of capturing fine particles is disposed in an exhaust duct that exhausts gas containing fine particles generated from a heating roller (fixing member) of a fixing device.

However, in a conventional image forming apparatus equipped with an exhaust duct, if the fixing device is configured to be detachable from the image forming apparatus body, the exhaust duct makes it difficult to attach and detach the fixing device.

In order to solve the above-mentioned problems, the present invention provides an image forming apparatus comprising a fixing device which fixes an image onto a recording material, and an exhaust duct which exhausts gas from within the fixing device, wherein the fixing device is configured to be detachable from the image forming apparatus main body, and has a moving means which moves an entrance of the exhaust duct to a use position connected to or close to an exhaust port of the fixing device and a retracted position retracted from the exhaust port, and an opening/closing door provided at the entrance/exit of the image forming apparatus main body through which the fixing device is inserted and removed, and the moving means moves the entrance of the exhaust duct to the retracted position in conjunction with the opening operation of the opening/closing door .

This invention makes it possible to avoid the situation where the exhaust duct makes it difficult to install and remove the fixing device.

1 is a schematic diagram of the overall configuration of a copying machine according to an embodiment; FIG. FIG. 2 is a perspective view illustrating a fixing device and an exhaust duct in the copying machine; FIG. 4 is an explanatory diagram showing a usage state (usage position) of an exhaust duct that exhausts gas from within the fixing device; FIG. 4 is an explanatory diagram showing another example of the fixing device in the copying machine. FIG. 4 is an explanatory diagram showing a retracted state (retracted position) of an exhaust duct that exhausts gas from within the fixing device; 1A is a side view of an end duct portion for explaining an example of a configuration of a moving means when a duct inlet member of the exhaust duct is in a use position, and FIG. 11 is an explanatory diagram showing a modified example in which a plurality of partition members are provided in each end area in the fixing device. FIG. 4 is an explanatory diagram of an example of a partition member in the fixing device when viewed from the paper width direction. FIG. 10 is an explanatory diagram of another example of the partition member in the fixing device when viewed from the paper width direction. FIG.

An embodiment of an image forming apparatus to which the present invention is applied will be described below.
In this embodiment, an electrophotographic copier (hereinafter simply referred to as "copier 1") that is a color image forming apparatus will be described as an example, but the present invention can also be applied to known monochrome image forming apparatuses, etc.

Fig. 1 is a schematic diagram of the overall configuration of a copying machine 1 according to this embodiment. Fig. 2 is a perspective explanatory diagram of the entire copying machine 1. Fig. 3 is a perspective explanatory diagram showing a fixing device and an exhaust duct in a see-through manner.
As shown in Fig. 1, the image forming section 110 of the copying machine main body includes four image forming devices 2 (2a, 2b, 2c, and 2d), an intermediate transfer device 3, a secondary transfer device 4, a paper transport device 5, a fixing device 6, and a toner supply device 7. In addition, a paper feed device 111, which is a recording material storage section including a paper feed tray 40 that is a recording material storage container for storing paper P, is provided below the image forming section 110 in Fig. 1, and a double-sided device 113 is provided on the right side of the image forming section 110 in Fig. 1. In addition, an image reading device 114 is provided above the image forming section 110 in Fig. 1, and an internal paper discharge section 112 is formed between the image forming section 110 and the image reading device 114. In addition, each member in the image forming section 110 is accommodated in an exterior cover 10.

The four image forming devices 2 (2a, 2b, 2c, and 2d) form different monochromatic images using toners of the colors yellow (Y), magenta (M), cyan (C), and black (K), respectively. Each image forming device 2 has a photoconductor 12, which is a drum-shaped latent image carrier that is rotatably supported, and the image forming section 110 of the copier 1 has four photoconductors 12 arranged in tandem. Each image forming device 2 has a charging device 13, which is a charging means, a developing device 14, which is a developing means, a primary transfer roller 15, which is a primary transfer means, a photoconductor cleaning device 16, which is a latent image carrier cleaning means, and a static eliminator 17, which is a static eliminator, arranged around the photoconductor 12. In FIG. 1, only the yellow image forming device 2a is labeled with the reference numerals of the respective members that constitute the image forming device 2, but the magenta image forming device 2b, the cyan image forming device 2c, and the black image forming device 2d also have the same configuration.

Furthermore, below the four image forming devices 2 (2a, 2b, 2c, and 2d) in the image forming section 110, a common exposure device 18 is provided, which is a latent image forming means that exposes the surface of each photoconductor 12 separately. The exposure device 18 includes optical components such as a light source and a lens, and irradiates the laser light emitted by the light source toward the surface of the photoconductor 12 through the optical components, optically scanning the surface of the photoconductor 12 and performing optical writing.

The intermediate transfer device 3 includes an intermediate transfer belt 20, which is a belt-shaped primary transfer image carrier on which the toner images of each color formed by each image forming device 2 (2a, 2b, 2c, and 2d) are primarily transferred and carried by the primary transfer roller 15. In the intermediate transfer device 3, the intermediate transfer belt 20 is wound around three support rollers: an intermediate transfer belt first support roller 21, an intermediate transfer belt second support roller 22, and an intermediate transfer belt third support roller 23. The intermediate transfer belt 20 is also brought into contact with each photoconductor 12, and passes between the photoconductor 12 and each corresponding primary transfer roller 15. In addition, an intermediate transfer belt cleaning device 24 and a secondary transfer roller 25, which is a secondary transfer means, are arranged around the intermediate transfer belt 20.

The secondary transfer device 4 includes a secondary transfer belt 30, which is a belt-shaped secondary transfer image carrier that carries the toner image carried on the intermediate transfer belt 20 by secondary transfer roller 25 during double-sided printing. In the secondary transfer device 4, the secondary transfer belt 30 is wound around three support rollers: a secondary transfer belt first support roller 31, a secondary transfer belt second support roller 32, and a secondary transfer belt third support roller 33. The secondary transfer belt 30 is brought into contact with the intermediate transfer belt 20 and passed between the intermediate transfer belt 20 and the secondary transfer roller 25 to form a predetermined secondary transfer nip between the intermediate transfer belt 20 and the secondary transfer belt 30. In addition, a secondary transfer belt cleaning device 35 and a back image transfer device 36 that transfers the back image carried on the secondary transfer belt 30 to the paper P are arranged around the secondary transfer belt 30.

The paper feed device 111 is configured with two levels of paper feed trays 40 and paper feed rollers 41 that feed paper P from the paper feed trays 40, one above the other, and stores paper P in each of the two paper feed trays 40. The paper feed rollers 41 feed paper P one sheet at a time from the top of each of the two paper feed trays 40. The paper transport device 5, which is a recording material transport means, transports paper P fed from the paper feed device 111 so that the paper P passes between the intermediate transfer device 3 and the secondary transfer device 4 and passes through a paper transport path that is a recording material transport path that extends from the bottom to the top in FIG. 1. The paper transport device 5 includes a paper feed guide 42, a pair of registration rollers 43, a paper discharge guide 44, a pair of paper discharge rollers 45, etc.

The paper feed guide 42 guides the paper P sent out by the paper feed roller 41 toward the registration nip formed by the two rollers of the registration roller pair 43. The registration roller pair 43 stops the leading edge of the paper P guided and conveyed by the paper feed guide 42 by hitting it against the registration nip, and corrects the inclination of the paper P. Then, in time with the images on the surfaces of the intermediate transfer belt 20 and the secondary transfer belt 30, the paper P is sent toward the secondary transfer nip.

The paper discharge guide 44 guides the paper P after the image has been fixed by the fixing device 6 toward the paper discharge outlet 51. The paper discharge roller pair 45 arranged at the paper discharge outlet 51 discharges the paper P, which has been guided and transported by the paper discharge guide 44, toward the internal paper discharge section 112, toward the outside of the exterior cover 10 in the direction of the arrow a in FIG. 1.

The fixing device 6 fixes the toner image transferred from the intermediate transfer belt 20 and the secondary transfer belt 30 to the paper P. The fixing device 6 includes a pair of fixing rollers 61 consisting of a heating roller and a pressure roller, and heats and presses the paper P carrying the toner image. Note that the pressure roller in this embodiment also functions as a heating roller.

The copier 1 of this embodiment is also provided with an exhaust duct 100 that exhausts gas (air) from within the fixing device 6. This exhaust duct 100 is provided with a collection filter 104 and an exhaust fan 105 near the duct outlet. The exhaust duct 100 sucks in gas (air) containing fine particles and the like exhausted from within the fixing device 6 from the duct inlet by the airflow generated by the exhaust fan 105, and exhausts the gas after the fine particles and the like are collected by the collection filter 104 from the duct outlet on the back of the copier body to the outside of the copier body as shown by the arrow f in FIG. 3.

The toner supply device 7 supplies new toner to each of the four image forming devices 2 (2a, 2b, 2c, and 2d) using a powder pump or the like. The toner storage section 52 of the toner supply device 7 is provided with toner cartridges 53 (53a, 53b, 53c, and 53d) that each store a toner of each color.

When forming color images on both sides of paper P in the copying machine 1, the document is placed on the contact glass of the image reading device 114, and the start switch on the operation display unit 115 shown in FIG. 2 is pressed. Then, the photoconductor 12, one of the support rollers of the intermediate transfer belt 20 (21, 22 or 23), one of the support rollers of the secondary transfer belt 30 (31, 32 or 33), the paper feed roller 41, etc. rotate in time with each other.

In the four image forming devices 2 (2a, 2b, 2c, and 2d), as each photoconductor 12 rotates in the clockwise direction in FIG. 1, the surface of the photoconductor 12 is uniformly charged by each charging device 13. Then, writing is performed on the photoconductor 12 with individual writing light from a common exposure device 18 to form latent images for each color, and each developing device 14 deposits toner of each color onto the surface of the photoconductor 12, forming a toner image for each color on each photoconductor 12.

In the intermediate transfer device 3, one of the support rollers (21, 22 or 23) of the intermediate transfer belt 20 is driven to rotate, while the other two support rollers are driven to rotate, causing the intermediate transfer belt 20 to rotate counterclockwise in FIG. 1 in synchronization with the photoreceptor 12. A primary transfer bias is applied to each of the primary transfer rollers 15 that face the photoreceptor 12 across the intermediate transfer belt 20, and the toner images on the surface of each photoreceptor 12 are transferred sequentially to the intermediate transfer belt 20. This forms a first full-color image (image for the back side) by superimposing four color toner images on the surface of the intermediate transfer belt 20.

After the toner image is transferred to the intermediate transfer belt 20, the photoconductors 12 of the four image forming devices 2 (2a, 2b, 2c, and 2d) have residual toner remaining on their surfaces removed by the photoconductor cleaning devices 16, and the surface potential is removed by the charge removal devices 17. After that, the photoconductors 12 are again charged by their respective charging devices 13, latent images are written by the exposure devices 18, and the toner images are developed by their respective developing devices 14, and color toner images are formed again on the individual photoconductors 12.

In the secondary transfer device 4, one of the support rollers (31, 32 or 33) of the secondary transfer belt 30 is driven to rotate, while the other two support rollers are driven to rotate, and the secondary transfer belt 30 rotates in the clockwise direction in FIG. 1 in synchronization with the intermediate transfer belt 20. In the secondary transfer nip, a secondary transfer bias is applied to the secondary transfer roller 25 that faces the intermediate transfer belt 20 across the secondary transfer belt 30, and the toner image on the surface of the intermediate transfer belt 20 is transferred onto the secondary transfer belt 30. At this time, the secondary transfer belt cleaning device 35 rotates around the cleaning device support shaft 56 and is separated from the secondary transfer belt 30, and is in a non-cleaning state.

In the intermediate transfer device 3, the residual toner remaining on the surface of the intermediate transfer belt 20 after the first full-color image is transferred to the secondary transfer belt 30 is electrostatically removed by the intermediate transfer belt cleaning device 24. After that, the toner on the surface of each photoconductor 12 is transferred sequentially again onto the surface of the intermediate transfer belt 20 by each primary transfer roller 15, forming a second full-color image (image for the front side) in which four color toner images are superimposed on the surface of the intermediate transfer belt 20.

After the toner images of each color forming the second full-color image have been transferred, the photoconductors 12 of the four image forming devices 2 (2a, 2b, 2c, and 2d) have residual toner remaining on their surfaces removed by the photoconductor cleaning device 16. The potential on the surfaces is then removed by the charge removing device 17 in preparation for the next image forming cycle.

Meanwhile, the paper feeder 111 selectively rotates one of the two paper feed rollers 41 to feed the paper P from the paper feed tray 40. In the paper transport device 5, the paper P fed from the paper feeder 111 is guided by the paper feed guide 42, and the leading edge of the paper P is stopped by hitting it against the registration nip of the registration roller pair 43. Then, the registration roller pair 43 is rotated in time with the above-mentioned first full-color image and second full-color image, and the paper P is fed into the secondary transfer nip between the intermediate transfer belt 20 and the secondary transfer belt 30.

At the secondary transfer nip, a second transfer bias is applied to the secondary transfer roller 25 located on the back side of the paper P, thereby transferring the above-mentioned second full-color image on the front side of the intermediate transfer belt 20 to the front side of the paper P. Next, at the opposing portion between the back side image transfer device 36, which has conveyed the paper P slightly upward, and the secondary transfer belt 30, a back side image transfer bias is applied by the back side image transfer device 36. This causes the above-mentioned first full-color image on the front side of the secondary transfer belt 30 to be transferred to the back side of the paper P.

Then, the paper P with the toner images transferred to both sides is guided to the fixing device 6, where it passes through a fixing nip formed by a pair of fixing rollers 61, and heat and pressure are applied to fix the transferred images on both sides to the paper P. The paper P is then guided by the paper discharge guide 44, and the paper is appropriately redirected to a different destination by a path switching claw arranged midway along the paper transport path formed by the paper discharge guide 44. The paper P is then discharged from the paper discharge outlet 51 by the pair of paper discharge rollers 45 to the outside of the exterior cover 10, and is stacked face-down on the stack section 50 of the internal paper discharge section 112.

In the intermediate transfer device 3, the intermediate transfer belt cleaning device 24 removes the residual toner remaining on the surface of the intermediate transfer belt 20 after the second full-color image is transferred to the paper P. In the secondary transfer device 4, the secondary transfer belt cleaning device 35 removes the residual toner remaining on the surface of the secondary transfer belt 30 after the first full-color image is transferred to the paper P. At this time, the secondary transfer belt cleaning device 35, which was in a non-cleaning state when the first full-color image was transferred from the intermediate transfer belt 20, rotates about the cleaning device support shaft 56 and comes into contact with the secondary transfer belt 30 to be in a cleaning state. The residual toner on the surfaces of the intermediate transfer belt 20 and the secondary transfer belt 30 is removed, and each is prepared for carrying the next image.

When toner in each developing device 14 runs out due to continued image formation, toner of the same color is transported by a powder pump or the like from the toner cartridge 53 corresponding to the developing device 14 in the toner storage section 52 of the toner replenishing device J to replenish the toner. Also, when a jam prevents the transport of paper P, the opening and closing door 11 provided on the side of the copier body opens in the direction of arrow d in Figure 1. This allows the duplexer 113, which is configured as an integral part of the opening and closing door 11, to open in the direction of arrow d in Figure 1 around the duplexer support shaft 55 to open the paper transport path, allowing the jam to be cleared.

When forming a full-color image on one side of paper P in the copying machine 1 shown in FIG. 1, the toner images formed on the surfaces of the photoconductors 12 of the four image forming devices 2 (2a, 2b, 2c, and 2d) are transferred onto the surface of the intermediate transfer belt 20 to form a full-color image. Next, the full-color image is transferred onto one side of paper P being transported by the paper transport device 5 without being transferred to the secondary transfer belt 30 of the secondary transfer device 4. The transferred image is then fixed onto the paper P by the fixing device 6, and the paper is stacked face-down in page order on the stack section 50 of the internal paper discharge section 112 with the image side facing down.

When forming a two-color image or a monochrome image on paper P with the copier 1 shown in FIG. 1, a toner image is formed using one of the four image forming devices 2 (2a, 2b, 2c, and 2d) of the corresponding color. The toner image is transferred to paper P via the intermediate transfer belt 20 of the intermediate transfer device 3 or the secondary transfer belt 30 of the secondary transfer device 4.

Next, the exhaust duct 100 for exhausting air from the fixing device 6 will be described.
4 is an explanatory diagram showing an exhaust duct 100 for exhausting gas from within the fixing device 6 in this embodiment. Note that in FIG. 4, the fixing device 6 is shown in cross section.
3, the exhaust duct 100 provided in the copying machine 1 of this embodiment is composed of two end duct sections 101A, 101B and a common duct section 103 communicating with these end duct sections. The two end duct sections 101A, 101B are disposed near both end regions of the fixing roller pair 61, and the common duct section 103 is disposed so as to extend in the axial direction (paper width direction) of the fixing roller pair 61. Duct inlet members 102A, 102B are attached to the respective tips of the two end duct sections 101A, 101B, and each duct inlet member 102A, 102B constitutes an inlet of the exhaust duct 100.

The fixing device 6 is provided with a storage case 62 that stores the fixing roller pair 61, and exhaust ports 62a are formed on the upper surface of the storage case 62 near both end regions in the paper width direction. Duct inlet members 102A and 102B attached to the tip of each end duct section 101A and 101B of the exhaust duct 100 are connected to or positioned close to each exhaust port 62a of the fixing device 6 (use position).

As shown in FIG. 3, the end of the common duct section 103 on the front side of the copier is connected to an end duct section 101A arranged on the front side of the copier, and the middle part of the common duct section 103 is connected to an end duct section 101B arranged on the rear side of the copier. The end of the common duct section 103 further towards the rear side of the copier than the connection point with the end duct section 101B forms the outlet (duct outlet) of the exhaust duct 100, and communicates with the outside of the machine from the rear of the exterior cover 10 of the copier 1. A collection filter 104 and an exhaust fan 105 are provided at the end of this common duct section 103.

When the exhaust fan 105 is driven, an airflow toward the duct outlet side is generated in the exhaust duct 100, and an intake airflow is generated in the duct inlet members 102A, 102B of each end duct section 101A, 101B. This intake airflow causes the gas in the housing case 62 of the fixing device 6 to be exhausted from each exhaust port 62a to the duct inlet members 102A, 102B together with the fine particles in the housing case 62. The gas is then exhausted from the duct outlet to the outside of the machine through each end duct section 101A, 101B and the common duct section 103. At this time, the fine particles exhausted from the housing case 62 to the exhaust duct 100 are captured by the collection filter 104 provided near the duct outlet of the common duct section 103, and are prevented from being exhausted to the outside of the machine.

Overseas, especially in Europe, there is a high level of interest in the environment, and various certification standards exist for VOCs (Volatile Organic Compounds), ozone, dust, fine particles, and ultrafine particles that are generated during image formation, even for image forming devices such as copying machines, multifunction machines, and printers that use electrophotographic processes. A German government research institute has an eco-labeling system called the "Blue Angel Mark" (hereinafter abbreviated as BAM), and only certified products and services are allowed to use the label.

BAM certification requires clearing a variety of tests, one of which is the UFP (ultra fine particle) test, which came into force in 2013. The BAM emission test method involves placing the image forming device in an emission test room that is ventilated under specified conditions, operating the device continuously for 10 minutes under control from outside the test room, and measuring both the standby and operating states. UFP measurements are performed by connecting a designated aerosol measuring device to the test room, and particles are counted. This measuring device measures particle size and number. A representative model is the FMPS-3091 high-speed response particle sizer manufactured by TSI.

Specifically, the BAM standard requires that UPFs of 5.6 nm to 560 nm generated by image forming devices are measured using a particle measuring device called a Fast Mobility Particle Sizer (FMPS). The number of UPFs is required to be less than 3.5 x 1011 particles/10 minutes. For this reason, the mass of the UPFs is irrelevant, and only the number generated in a 10 minute period is subject to the standard.

The fine particles (including UFP) generated by the copier 1 are generated from various components, but since the amount of fine particles generated increases significantly just by starting and heating the fixing device 6 alone, it is known that the fixing device 6 is one of the causes of fine particle generation. It is known that lowering the fixing temperature of the fixing device 6, which generates the fine particles, is an effective way to reduce the total amount of fine particle emissions, but it is necessary to ensure the required fixing quality, and the fixing temperature cannot be lowered more than necessary.

The fine particles generated in the fixing device 6 include fine particles that are generated as follows.
As shown in Fig. 4, the heating roller constituting the fixing roller pair 61 has a multi-layer structure including a base material 61a made of a cylindrical core metal or an annular endless belt, an elastic layer 61b provided so as to cover the outer peripheral surface of the base material 61a, and a surface layer 61c provided so as to cover the outer peripheral surface of the elastic layer 61b. The elastic layer 61b and the surface layer 61c are disposed in the longitudinal center portion of the base material 61a, and the elastic layer 61b and the surface layer 61c are not present on both ends of the base material 61a. The elastic layer 61b is made of, for example, a silicone rubber material, and has heat resistance to the fixing temperature and elasticity to ensure the necessary nip width.

The heating roller is heated to a temperature (fixing temperature) required for the fixing process by a heating means such as a heater disposed inside the base material, and when the temperature of the heating roller rises, siloxane is generated as fine particles from the silicone rubber material that constitutes the elastic layer 61b of the heating roller. These fine particles cannot pass through the surface layer 61c, so they do not spray out from the part where the elastic layer 61b is covered by the surface layer 61c (the outer peripheral surface of the elastic layer 61b). However, since each end face of the elastic layer 61b is not covered by the surface layer 61c, the fine particles are sprayed out from each end face of the elastic layer 61b. Therefore, in the fixing device 6, the fine particles are generated near both ends of the heating roller. In particular, since both ends of the fixing roller pair 61 are outside the paper passing area (width through which the paper passes), heat is not easily taken away by the paper being passed through, and the temperature drop is small, so they are prone to becoming hot and fine particles are likely to be generated.

In addition, the pressure roller that constitutes the fixing roller pair 61 may also be made of a material that generates fine particles. In this case, fine particles are also generated near both ends of the pressure roller.

In addition, the fine particles generated in the fixing device 6 are not limited to those generated from the elastic layer of the heating roller or pressure roller. For example, as shown in FIG. 5, in a configuration in which a pressure pad 61C for receiving the pressure of the pressure roller 61B is arranged on the inner circumferential surface of the fixing belt 61A as a fixing member, a lubricant such as silicone oil is used to reduce the frictional force between the inner circumferential surface of the fixing belt 61A and the pressure pad 61C. In this configuration, when the lubricant (silicone oil) is heated by the heater 61D, it generates fine particles, just as in the case of the elastic layer (silicone material) described above. These fine particles are generated within the loop of the fixing belt 61A, but cannot pass through the fixing belt 61A, so they flow to each end of the fixing belt 61A and leak out from each end of the fixing belt 61A.

As described above, fine particles generated in the fixing device 6 are likely to be generated near the ends of the fixing roller pair 61. Therefore, in this embodiment, as shown in FIG. 4, the exhaust port 62a formed in the housing 62 of the fixing device 6 is provided to face the vicinity of each end of the fixing roller pair 61 where fine particles are likely to be generated. This allows the fine particles generated near each end of the fixing roller pair 61 to be efficiently sucked into the exhaust duct 100, and collected by the collection filter 104 of the exhaust duct 100, thereby reducing the amount of the fine particles discharged outside the copier 1.

Here, the fixing device 6 of this embodiment is configured to be detachable from the copier body so that a serviceman or the like can repair or maintain the fixing device 6. In this embodiment, by opening the opening door 11 provided on the side of the copier body in the direction of the arrow d in FIG. 1, the fixing device 6 can be exposed to the outside through the side opening of the copier body that was closed by the opening door 11. Then, the serviceman or the like can remove the fixing device 6 from the copier body by pulling the fixing device 6 horizontally out of the side opening of the copier body. Note that when attaching the fixing device 6 to the copier body, the serviceman or the like pushes the fixing device 6 horizontally through the side opening of the copier body.

If the duct inlet of the exhaust duct 100 is attached to the exhaust port 62a of the fixing device 6, the duct inlet must be removed from the fixing device 6 when attaching or detaching the fixing device 6, which makes the attachment and detachment of the fixing device 6 complicated. Also, if the duct inlet of the exhaust duct 100 is connected to or close to the exhaust port 62a of the fixing device 6, the exhaust duct 100 will interfere if left in this state, making the attachment and detachment of the fixing device 6 complicated.

To eliminate the complication of such installation and removal of the fixing device 6, the copier 1 of this embodiment is provided with a moving means for moving the duct inlet of the exhaust duct 100 between a use position connected to or close to the exhaust port 62a of the fixing device 6 and a retracted position retracted from the exhaust port 62a. Specifically, the moving means of this embodiment moves the duct inlet members 102A, 102B of the two end duct parts 101A, 101B connected to the common duct part 103 along a direction approaching and retracting from the exhaust port 62a of the fixing device 6.

As shown in FIG. 4, a spring 107 is attached as a biasing means between the rib 101a provided on the end duct parts 101A and 101B and the duct inlet members 102A and 102B. The biasing force of the spring 107 biases the duct inlet members 102A and 102B in a direction away from the exhaust port 62a of the fixing device 6.

When the duct inlet members 102A and 102B are moved toward the exhaust port 62a by the moving means against the biasing force of the spring 107, the duct inlet members 102A and 102B take the use position (the state shown in FIG. 4). In this state, the duct inlet members 102A and 102B are connected to or close to the exhaust port 62a of the fixing device 6, and fine particles generated in the fixing device 6 can be sucked into the exhaust duct 100 from the exhaust port 62a via the duct inlet members 102A and 102B.

On the other hand, when the duct inlet members 102A and 102B are moved away from the exhaust port 62a by the biasing force of the spring 107 using the moving means, the duct inlet members 102A and 102B take the retracted position (the state shown in FIG. 6). In this state, the duct inlet members 102A and 102B are away from the exhaust port 62a of the fixing device 6, so that the exhaust duct 100 does not interfere when the fixing device 6 is attached or detached, making it easier to attach and detach the fixing device 6.

In this embodiment, the elastic member 102b made of sponge is provided at the inlet edge of the duct inlet members 102A and 102B. As a result, when the duct inlet members 102A and 102B are moved to the use position, even if there is a variation in the parts, the elastic member 102b deforms and closes the gap between the duct inlet members 102A and 102B and the housing case 62 of the fixing device 6. Therefore, the duct inlet members 102A and 102B can be stably attached to the housing case 62 of the fixing device 6. Therefore, fine particles generated in the fixing device 6 can be reliably sucked into the exhaust duct 100 from the exhaust port 62a of the housing case 62 through the duct inlet members 102A and 102B.

In addition, in this embodiment, the exhaust port 62a formed in the housing case 62 of the fixing device 6 is formed on the upper surface of the housing case 62. The gas containing fine particles generated inside the housing case 62 moves as an ascending air current due to its high temperature. Therefore, by forming the exhaust port 62a on the upper surface of the housing case 62, it is possible to exhaust the gas inside the housing case 62 from the exhaust port 62a to the exhaust duct 100 by utilizing not only the air current sucked in by the exhaust fan 105 but also this ascending air current, enabling more efficient exhaust.

7A and 7B are side views of the end duct portions 101A and 101B for explaining an example of the moving means of this embodiment.
The moving means of this embodiment moves the duct inlet members 102A, 102B of the exhaust duct 100 to the retracted position in conjunction with the opening operation of the opening/closing door 11. Specifically, an engaged rib 102a is provided as an engaged portion on the outer surface of the duct inlet members 102A, 102B. The engaged rib 102a has an inclined surface 102a1 and a horizontal surface 102a2.

When the opening and closing door 11 is closed, as shown in FIG. 7(a), the engaging rib 11a provided on the opening and closing door 11 is located on the horizontal surface 102a2 of the engaged rib 102a of the duct inlet members 102A and 102B. At this time, the duct inlet members 102A and 102B are pushed down against the biasing force of the spring 107 and positioned in the use position, as shown by the white arrow in FIG. 7(a). The movement of the duct inlet members 102A and 102B, which attempt to move upward due to the biasing force of the spring 107, is restricted by the engaging rib 11a of the opening and closing door 11 abutting against the horizontal surface 102a2 of the engaged rib 102a. As a result, the duct inlet members 102A and 102B are positioned in the use position where they are connected to or close to the exhaust port 62a of the storage case 62 of the fixing device 6.

When the opening/closing door 11 is opened from the state shown in FIG. 7(a), the engaging rib 11a of the opening/closing door 11 moves (rotates) in the direction of the arrow d, as shown in FIG. 7(b). This releases the restriction on the movement of the duct inlet members 102A and 102B, which are attempting to move upward due to the biasing force of the spring 107, and the duct inlet members 102A and 102B move upward due to the biasing force of the spring 107, as shown by the white arrow in FIG. 7(b). As a result, the duct inlet members 102A and 102B are positioned at a retracted position where they are retracted from the exhaust port 62a of the storage case 62 of the fixing device 6.

As a result, when the opening and closing door 11 on the side of the copier body is opened during repair or maintenance of the fixing device 6, the duct inlet members 102A and 102B of the exhaust duct 100 move from the use position to the retracted position in conjunction with this opening action. Therefore, a service person or the like can remove the fixing device 6 from the side opening of the copier body without removing the duct inlet from the fixing device 6 and without interference from the exhaust duct 100.

The moving means of this embodiment also moves the duct inlet members 102A and 102B of the exhaust duct 100 to the use position in conjunction with the closing operation of the opening and closing door 11. That is, when the opening and closing door 11 is closed from the state shown in FIG. 7(b), the engaging rib 11a of the opening and closing door 11 moves (rotates) in the direction of the arrow d' as shown in FIG. 7(a). Then, when the engaging rib 11a of the opening and closing door 11 comes into contact with the inclined surface 102a1 of the engaged rib 102a of the duct inlet members 102A and 102B, and the engaging rib 11a is further moved in the direction of the arrow d', the engaging rib 11a moves so as to slide on the inclined surface 102a1. As a result, the duct inlet members 102A and 102B on which the inclined surface 102a1 is provided are pushed down against the biasing force of the spring 107 as shown by the white arrow in FIG. 7(a). When the opening and closing door 11 is closed, the engaging rib 11a moves to the horizontal surface 102a2 of the engaged rib 102a, and the duct inlet members 102A and 102B are positioned in the use position.

As a result, when the opening and closing door 11 provided on the side of the copier body is closed, the duct inlet members 102A and 102B of the exhaust duct 100 move from the retracted position to the use position in conjunction with the closing action. Therefore, a service person or the like can attach the fixing device 6 to the copier body without performing the work of attaching a duct inlet to the fixing device 6 and without interference from the exhaust duct 100.

In addition, in this embodiment, as shown in FIG. 4, the intake port 62b of the fixing device 6 is arranged on the storage case 62 at a position facing the end region of the fixing roller pair 61 in the paper width direction. Like the exhaust port 62a, the intake port 62b is arranged at a position facing the end region of the fixing roller pair 61 in the paper width direction, so that the gas sucked into the storage case 62 from the intake port 62b carries fine particles generated in the end region of the fixing roller pair 61 and is exhausted from the exhaust port 62a to the exhaust duct 100. In this case, the gas near the central region of the fixing roller pair 61 is less likely to flow out to the exhaust duct 100, so the temperature of the central region of the fixing roller pair 61 that contacts the paper P and performs the fixing process is less likely to drop. As a result, the drop in the fixing temperature is suppressed, and benefits such as suppressing power consumption are obtained.

In this embodiment, the intake port 62b is disposed opposite the exhaust port 62a (directly below the exhaust port 62a), but the position is not limited to the position opposite the exhaust port 62a as long as it is opposite the end region of the fixing roller pair 61 in the paper width direction.

In addition, as shown in FIG. 4, the fixing device 6 in this embodiment is provided with a partition member 63 that divides the internal space of the storage case 62 in the paper width direction. This partition member 63 is located closer to the center in the paper width direction than the exhaust port 62a of the storage case 62. Without such a partition member 63, fine particles generated in the end region of the fixing roller pair 61 may be drawn into the transport airflow of the paper P transported in the central region of the fixing roller pair 61 and may flow out from the paper outlet of the storage case 62.

By providing the partition member 63 as in this embodiment, fine particles generated in the end region of the fixing roller pair 61 are less likely to be drawn into the airflow transporting the paper P, and the fine particles can be prevented from escaping from the paper outlet of the storage case 62. As a result, most of the fine particles generated in the end region of the fixing roller pair 61 can be sent into the exhaust duct 100 and efficiently collected by the collection filter 104.

In particular, in this embodiment, the partition member 63 is disposed outside the widthwise end position of the maximum width paper P (the end position of the paper passing range shown in FIG. 4) and inside the paper widthwise end position of the fixing roller pair 61 (the position of the end face of the elastic layer 61b). This makes it possible to send many of the fine particles generated in the end region of the fixing roller pair 61 into the exhaust duct 100, and to obtain a high effect of efficiently collecting them by the collection filter 104.

In addition, by providing the partition member 63 as in this embodiment, the gas near the central region of the fixing roller pair 61 is less likely to flow toward the end regions, and as a result, the temperature of the central region of the fixing roller pair 61, which comes into contact with the paper P and performs the fixing process, is less likely to drop. As a result, the drop in the fixing temperature is suppressed, and benefits such as reduced power consumption are obtained.

Furthermore, by providing the partition member 63 as in this embodiment, the gas near the central region of the fixing roller pair 61 is less likely to flow toward the end regions, and as a result, the diffusion of fine particles generated from the toner on the paper transported through the central region of the fixing roller pair 61 can be suppressed. In general, the higher the concentration of fine particles, the more they tend to bond (aggregate). Therefore, by suppressing diffusion in this way and increasing the concentration of fine particles generated from the toner, the bonding (aggregation) of fine particles can be promoted. As a result, the particle size of the fine particles can be increased, making it easier for the fine particles to adhere to the wall surfaces of the copier 1 and easier for the fine particles to be captured by filters or the like installed in the copier, and the amount of fine particles discharged outside the machine can be reduced.

In this embodiment, there is only one partition member 63 (one in each end region) that separates the end region where the exhaust port 62a is provided from the central region, but as shown in FIG. 8, multiple partition members 63 may be provided for each end region. For example, it is advisable to provide each partition member 63 in accordance with the widthwise end positions of multiple types of widthwise sizes (multiple standard sizes). In this way, even if the width sizes of the paper P are different, the partition member 63 can efficiently suppress the diffusion of fine particles generated from the toner on the paper P and effectively promote the bonding (aggregation) of the fine particles.

In order to obtain the above-mentioned effects of the partition member 63, it is preferable that the partition member 63 is provided so as to separate the entire periphery of the fixing roller pair 61, as shown in FIG. 9. In other words, it is preferable that the shape of the partition member 63 is configured to follow the outer diameter of the fixing roller pair 61, as shown in FIG. 9.

When the partition member 63 is positioned near the central region of the fixing roller pair 61 (within the paper passage range through which the paper P is transported), the partition member 63 that separates the entire periphery of the fixing roller pair 61 as shown in FIG. 9 will hinder the transport of the paper P. In such a case, as shown in FIG. 10, a partition member 63 that is shaped so as not to separate the portion of the entire periphery of the fixing roller pair 61 that would hinder the transport of the paper P may be used.

The above description is merely an example, and each of the following aspects provides unique effects.
[First aspect]
The first aspect is an image forming apparatus (e.g., copier 1) equipped with a fixing device 6 that fixes an image on a recording material (e.g., paper P) and an exhaust duct 100 that exhausts gas from within the fixing device, wherein the fixing device is configured to be detachable from the image forming apparatus main body (e.g., copier main body) and is characterized in having a moving means (e.g., spring 107, engaging rib 11a, engaged rib 102a, etc.) that moves the inlet of the exhaust duct (e.g., duct inlet members 102A, 102B) between a use position connected to or close to an exhaust port 62a of the fixing device and a retracted position retracted from the exhaust port.
In this aspect, the inlet of the exhaust duct is moved by the moving means to a use position connected to or close to the exhaust port of the fixing device, so that the gas inside the fixing device can be exhausted through the exhaust duct. The moving means can move the inlet of the exhaust duct to a retracted position away from the exhaust port of the fixing device. By moving the inlet of the exhaust duct to the retracted position by the moving means, the operation of removing the exhaust duct from the fixing device during the installation and removal of the fixing device to and from the image forming device body is eliminated. In addition, it is possible to avoid a situation in which the exhaust duct interferes with the installation and removal of the fixing device to and from the image forming device body. In this way, according to this aspect, it is possible to avoid a situation in which the installation and removal of the fixing device becomes complicated due to the exhaust duct.

[Second aspect]
The second aspect is characterized in that in the first aspect, there is provided an opening/closing door 11 provided at an entrance of the main body (for example, a side opening of the copier main body) through which the fixing device is inserted and removed, and the moving means moves the entrance of the exhaust duct to the retracted position in conjunction with the opening operation of the opening/closing door.
According to this, the inlet of the exhaust duct can be moved from the use position to the retracted position simply by opening the door of the image forming apparatus body, and therefore the fixing device can be removed from the entrance of the image forming apparatus body without removing the duct inlet from the fixing device and without being interfered with by the exhaust duct.

[Third aspect]
The third aspect is characterized in that in the first or second aspect, the device has an opening/closing door 11 provided at an entrance of the main body through which the fixing device is inserted and removed, and the moving means moves the entrance of the exhaust duct to the usage position in conjunction with the closing operation of the opening/closing door.
According to this, the inlet of the exhaust duct can be moved from the retracted position to the use position simply by closing the door of the image forming apparatus body. Therefore, the fixing device can be attached from the entrance of the image forming apparatus body without interference from the exhaust duct, and the exhaust duct can be moved to the use position and used without the need to attach the duct inlet to the fixing device.

[Fourth aspect]
The fourth aspect is characterized in that, in any of the first to third aspects, the fixing device fixes a recording material (e.g., paper P) while transporting the recording material by clamping it between a fixing member (e.g., a heating roller, a fixing belt, etc.) and a pressure member (e.g., a pressure roller), and an exhaust port 62a of the fixing device is arranged on a storage case 62 that houses at least one of the fixing member and the pressure member (e.g., a pair of fixing rollers 61) in a position facing an end region of the at least one member in the recording material width direction (e.g., the paper width direction) perpendicular to the recording material transport direction.
In the fixing device, fine particles are generated near the edge region of at least one of the fixing member and the pressure member. According to this aspect, the fine particles generated near the edge region can be efficiently exhausted from the exhaust port to the exhaust duct.

[Fifth aspect]
The fifth aspect is characterized in that, in the fourth aspect, the air intake 62b of the fixing device is arranged on the storage case 62 at a position opposite the recording material width direction end region of at least one of the members (e.g., a pair of fixing rollers 61).
According to this aspect, the gas sucked into the housing case from the intake port carries fine particles generated in the end region of the at least one member and is exhausted from the exhaust port to the exhaust duct. This reduces the amount of gas near the center region of the at least one member that flows out to the exhaust duct, so the temperature of the center region of the at least one member that comes into contact with the recording material and performs the fixing process is less likely to drop. As a result, the drop in the fixing temperature is suppressed, and benefits such as reduced power consumption are obtained.

[Sixth aspect]
The sixth aspect is characterized in that, in the fourth or fifth aspect, the fixing device has a partition member 63 that divides the internal space of the storage case in the width direction of the recording material, and the partition member is positioned closer to the center in the width direction of the recording material than the exhaust port 62a.
Without such a partition member, fine particles generated in the end region of the at least one member may be drawn into the airflow of the recording material transported in the central region of the at least one member and may flow out from the recording material outlet of the storage case. By providing a partition member as in this embodiment, fine particles generated in the end region of the at least one member are less likely to be drawn into the airflow of the recording material transported, and the fine particles can be prevented from flowing out from the recording material outlet of the storage case. As a result, most of the fine particles generated in the end region of the at least one member can be sent to the exhaust duct.

[Seventh aspect]
A seventh aspect is the sixth aspect, characterized in that the partition member is positioned outside the end position in the recording material width direction of the widest recording material and inside the end position in the recording material width direction of at least one of the members.
This allows many of the fine particles generated in the end region of the at least one member to be sent into the exhaust duct.

[Eighth aspect]
An eighth aspect is characterized in that in any one of the first to seventh aspects, a filter member (e.g., a collection filter 104) is provided to capture fine particles in the gas exhausted by the exhaust duct.
According to this, the gas exhausted from inside the fixing device to the exhaust duct can be discharged to the outside of the image forming apparatus main body in a state in which fine particles contained in the gas have been removed by the filter member.

[Ninth aspect]
The ninth aspect is a fixing device 6 that fixes an image onto a recording material (e.g., paper P) while sandwiching the recording material between a fixing member (e.g., a heating roller, fixing belt, etc.) and a pressure member (e.g., a pressure roller) and transporting the recording material, and is characterized in that the fixing device 6 includes a storage case 62 that contains at least one of the fixing member and the pressure member (e.g., a pair of fixing rollers 61), and a partition member 63 that divides the internal space of the storage case in a recording material width direction (e.g., the paper width direction) perpendicular to the recording material transport direction, and the partition member is positioned outside the recording material width direction end position of the widest recording material and inside the recording material width direction end position of the at least one member.
In the fixing device, fine particles are generated near the end region of at least one of the fixing member and the pressure member. Without such a partition member, the fine particles generated in the end region of the at least one member may be drawn into the conveying airflow of the recording material conveyed in the central region of the at least one member and may flow out from the recording material outlet of the storage case. By providing a partition member such as this embodiment, the fine particles generated in the end region of the at least one member are less likely to be drawn into the conveying airflow of the recording material, and the fine particles can be prevented from flowing out from the recording material outlet of the storage case. As a result, it is possible to prevent the fine particles from being discharged to the outside of the image forming apparatus main body.

[Tenth aspect]
The tenth aspect is an image forming apparatus (e.g., a copier 1) equipped with a fixing device 6 for fixing an image onto a recording material, characterized in that the fixing device is the fixing device of the ninth aspect.
This makes it possible to prevent fine particles generated within the fixing device from being discharged to the outside of the main body of the image forming apparatus.

1: Copying machine 2: Image forming device 3: Intermediate transfer device 4: Secondary transfer device 5: Paper conveying device 6: Fixing device 7: Toner supply device 10: Exterior cover 11: Opening and closing door 11a: Engagement rib 12: Photoconductor 13: Charging device 14: Development device 15: Primary transfer roller 18: Exposure device 20: Intermediate transfer belt 25: Secondary transfer roller 30: Secondary transfer belt 36: Rear image transfer device 40: Paper feed tray 43: Registration roller pair 50: Stack section 55: Double-sided device support shaft 61: Fixing roller pair 61a: Base material 61b: Elastic layer 61c: Surface layer 61A: Fixing belt 61B: Pressure roller 61C: Pressure pad 61D: Heater 62: Storage case 62a: Exhaust port 62b: Intake port 63: Partition member 100 : Exhaust duct 101A, 101B: End duct portion 101a: Ribs 102A, 102B: Duct inlet member 102a: Engaged rib 102a1: Inclined surface 102a2: Horizontal surface 102b: Elastic member 103: Common duct portion 104: Collection filter 105: Exhaust fan 107: Spring 110: Image forming portion 111: Paper feed device 112: Internal paper discharge portion 113: Double-sided device 114: Image reading device 115: Operation display portion P: Paper

JP 2011-180340 A

Claims (9)

a fixing device for fixing the image onto the recording material;
an exhaust duct for exhausting gas from within the fixing device,
the fixing device is configured to be detachable from the main body of the image forming apparatus,
a moving unit for moving an inlet of the exhaust duct between a use position connected to or close to an exhaust port of the fixing device and a retreat position retracted from the exhaust port ;
an opening and closing door provided at an entrance of a main body of the image forming apparatus for inserting and removing the fixing device ,
The image forming apparatus according to claim 1, wherein the moving means moves the inlet of the exhaust duct to the retracted position in conjunction with an opening operation of the opening/closing door . 2. The image forming apparatus according to claim 1 ,
an opening/closing door provided at an entrance of a main body of the image forming apparatus for inserting and removing the fixing device;
The image forming apparatus according to claim 1, wherein the moving means moves the inlet of the exhaust duct to the use position in conjunction with a closing operation of the opening/closing door. a fixing device for fixing the image onto the recording material;
an exhaust duct for exhausting gas from within the fixing device,
the fixing device is configured to be detachable from the main body of the image forming apparatus,
a moving unit for moving an inlet of the exhaust duct between a use position connected to or close to an exhaust port of the fixing device and a retreat position retracted from the exhaust port;
an opening and closing door provided at an entrance of a main body of the image forming apparatus for inserting and removing the fixing device,
The image forming apparatus according to claim 1, wherein the moving means moves the inlet of the exhaust duct to the use position in conjunction with a closing operation of the opening/closing door. 4. The image forming apparatus according to claim 1,
The fixing device fixes the recording material while conveying the recording material by sandwiching the recording material between a fixing member and a pressure member,
An image forming apparatus characterized in that an exhaust port of the fixing device is arranged on a storage case that contains at least one of the fixing member and the pressure member, at a position opposite an end region of the at least one of the members in a recording material width direction perpendicular to a recording material transport direction. a fixing device for fixing the image onto the recording material;
an exhaust duct for exhausting gas from within the fixing device,
the fixing device is configured to be detachable from the image forming apparatus main body, and fixes the recording material while conveying the recording material by nipping it between a fixing member and a pressure member;
a moving unit for moving an inlet of the exhaust duct between a use position connected to or close to an exhaust port of the fixing device and a retreat position retreated from the exhaust port,
An image forming apparatus characterized in that an exhaust port of the fixing device is arranged on a storage case that contains at least one of the fixing member and the pressure member, at a position opposite an end region of the at least one of the members in a recording material width direction perpendicular to a recording material transport direction. 6. The image forming apparatus according to claim 4,
an intake port of the fixing device is disposed on the housing case at a position facing an end region of the at least one member in a width direction of the recording material; 7. The image forming apparatus according to claim 4,
the fixing device has a partition member that divides the internal space of the housing in the width direction of the recording material,
The image forming apparatus according to claim 1, wherein the partition member is disposed closer to the center in the width direction of the recording material than the exhaust port. 8. The image forming apparatus according to claim 7 ,
An image forming apparatus characterized in that the partition member is arranged outside the end position of the recording material width direction of the widest recording material and inside the end position of the recording material width direction of at least one of the members. 9. The image forming apparatus according to claim 1,
an exhaust duct for exhausting gas from the exhaust port of the image forming apparatus ;

Images