JP7690272B2 - Recording material cooling device, image forming apparatus - Google Patents

Description

The present invention relates to a recording material cooling device that cools recording material via a belt and is suitable for use in image forming devices such as printers, copiers, facsimiles, and multifunction devices, and to an image forming apparatus equipped with the same.

In an image forming apparatus, a toner image formed on a recording material is heated and pressurized by a fixing device to fix the toner image to the recording material. The toner image is fixed to the recording material by sandwiching and conveying the recording material between a fixing roller heated by a halogen heater or the like and a pressure roller pressed against the fixing roller. When the toner image is fixed, the recording material is heated, so the temperature of the recording material conveyed from the fixing device becomes higher than before fixing. If the recording material after the toner image is fixed is loaded on the stacking section while still at a high temperature, there is a risk that the loaded recording materials will stick to each other due to the toner. In order to prevent such sticking of the recording material, a recording material cooling device is provided that lowers the temperature of the recording material after the toner image is fixed (Patent Document 1). The recording material cooling device described in Patent Document 1 is a belt cooling type device, in which a belt that sandwiches and conveys the recording material conveyed from the fixing device is cooled by a heat sink, and the temperature of the recording material is lowered through the belt.

When the belt is cooled by the heat sink as described above, the belt is in contact with the heat sink under a certain pressure in order to efficiently cool the belt. Therefore, the rotating belt may be scraped by the heat sink, generating wear dust (also called abrasion dust). This wear dust adheres to the belt and is carried as an attachment together with paper dust and the like, and tends to accumulate at the upstream end of the heat sink. If the amount of accumulated attachment increases and some of the accumulated attachment gets between the heat sink and the belt, this may increase the thermal resistance and reduce the cooling performance of the recording material. Therefore, a cooling device has been proposed that includes a cleaning member such as a blade or fur brush that removes the attachment, including the wear dust of the belt scraped by the heat sink, from the belt, and a case that receives the attachment removed by the cleaning member (Patent Document 2).

JP 2009-181055 A JP 2015-94847 A

Incidentally, some recording material cooling devices are equipped with a mechanism for swinging an upper unit having a belt to separate the belt from a conveying member that contacts the belt and nip-conveys the recording material together with the belt. This is because separating the belt from the conveying member makes it easier to remove recording material that has accumulated in the conveying nip where the belt and conveying member nip-conveys the recording material, for example, in the event of an abnormality in the conveyance of the recording material. It is conceivable to apply the device described in Patent Document 2 to such a recording material cooling device that has a mechanism for swinging the upper unit. However, in this case, there is a risk that attached matter will overflow from the case when the upper unit is rotated.

In view of the above problems, the present invention aims to provide a recording material cooling device that uses a belt cooling system and has a mechanism for oscillating the belt relative to a conveying member that sandwiches and conveys the recording material together with the belt, and that can prevent deposits from spilling out of the case when the belt is oscillated.

A recording material cooling device according to one embodiment of the present invention is a recording material cooling device that cools a recording material that has passed through a fixing device that fixes a toner image to the recording material by heating, the recording material cooling device comprising: a belt; a plurality of rollers around which the belt is stretched; a cooling section that contacts an inner peripheral surface of the belt to cool the belt; a conveying section that contacts an outer peripheral surface of the belt to form a nip section through which the recording material on which a toner image has been formed is conveyed; a removing section that removes deposits that have adhered to the inner peripheral surface of the belt; a receiving container having an opening that receives the deposits removed by the removing section; and a holding section that holds the plurality of rollers, the cooling section, and the receiving container and is capable of swinging between a first position where the nip section is formed between the belt and the conveying section and a second position where the belt is separated from the conveying section, the plurality of rollers including a drive roller that drives the belt, The oscillation center of the holding portion extends in a direction intersecting the rotational axis direction of the drive roller and the vertical direction, and the receiving container has a bottom portion extending in the rotational axis direction of the drive roller to receive the adhesions, and a first wall portion and a second wall portion at both ends of the bottom portion in the rotational axis direction, and a partition portion that divides the inside of the receiving container into a plurality of storage chambers between the first wall portion and the second wall portion in the rotational axis direction, the first partition portion being located on the first wall portion side of the center between the first wall portion and the second wall portion, and a second partition portion being located on the second wall portion side of the center between the first wall portion and the second wall portion, and both the first partition portion and the second partition portion are formed obliquely so that the downstream end side in the movement direction of the belt is closer to the oscillation center than the upstream end side .

According to the present invention, when the receiving container that receives the adhesions removed from the belt by the removal section is oscillated relative to the conveying section that clamps and conveys the recording material together with the belt, it is possible to prevent the adhesions from falling from the receiving container.

FIG. 1 is a schematic diagram illustrating a configuration of an image forming apparatus. FIG. FIG. 2 is a schematic diagram showing a recording material cooling device according to the embodiment. 1A is a diagram showing a state in which the belts are in contact with each other, and FIG. 1B is a diagram showing a state in which the belts are separated from each other. FIG. 2 is a perspective view showing the collection box according to the first embodiment. 5A and 5B are diagrams showing the accumulation state of deposits in the collection box, where FIG. 5A is a diagram showing the accumulation state of deposits in the collection box when an experiment was performed under condition 1, and FIG. 5B is a diagram showing the accumulation state of deposits in the collection box when an experiment was performed under condition 2. 13A is a perspective view showing a collection box according to a second embodiment, and FIG. 13B is a diagram showing an accumulation state of deposits in the collection box after swinging. FIG. 13 is a schematic diagram showing an example in which a recording material cooling device is provided outside an image forming apparatus. 11A and 11B are diagrams for explaining the wall portion of the collection box, in which (a) is a cross-sectional view cut in the thickness direction of the first belt at the ridge line position, (b) is a diagram viewed from above in the vertical direction showing another embodiment of the wall portion, and (c) is a diagram viewed from above in the vertical direction showing yet another embodiment of the wall portion.

First Embodiment
[Image forming apparatus]
The recording material cooling device of this embodiment will be described below. First, the schematic configuration of an image forming apparatus suitable for using the recording material cooling device of this embodiment will be described with reference to FIGS. 1 and 2. The image forming apparatus 100 shown in FIG. 1 is a tandem-type full-color printer of an electrophotographic system. The image forming apparatus 100 has image forming units PY, PM, PC, and PK that form images of yellow, magenta, cyan, and black, respectively. The image forming apparatus 100 forms a toner image on a recording material S in response to an image signal from an external device, such as a document reading device (not shown) connected to the apparatus main body 100A or a personal computer connected to the apparatus main body 100A so as to be communicable therewith. In this embodiment, an image forming unit 500 that forms a toner image on a recording material S is configured by the image forming units PY to PK, a primary transfer roller 5, an intermediate transfer belt 8, a plurality of rollers (9, 9a, 9b), and a secondary transfer roller 10. In addition, the recording material S may be various types of sheet materials, such as plain paper, thick paper, rough paper, uneven paper, coated paper, and the like, plastic film, cloth, and the like.

As shown in FIG. 1, the image forming units PY, PM, PC, and PK are arranged in line in the moving direction of the intermediate transfer belt 8 in the apparatus main body 100A. The intermediate transfer belt 8 is stretched around a number of rollers (9, 9a, 9b) and is configured to move (rotate) in the direction of the arrow R2 in the figure. The intermediate transfer belt 8 carries and transports the toner image that has been primarily transferred. A secondary transfer roller 10 is arranged at a position facing the roller 9 that stretches the intermediate transfer belt 8 across the intermediate transfer belt 8, forming a secondary transfer unit T2 that transfers the toner image on the intermediate transfer belt 8 to the recording material S. A fixing device 11 is arranged downstream of the secondary transfer unit T2 in the recording material transport direction. In addition, a transport unit 90 and a recording material cooling device 20 are arranged downstream of the fixing device 11 in the recording material transport direction, in that order from the upstream side.

At the bottom of the image forming apparatus 100, a cassette 12 containing recording material S is disposed. The recording material S is transported by transport rollers 13 from the cassette 12 to registration rollers 14 along a transport path 600 that forms a path for the recording material S within the apparatus main body 100A. Thereafter, the registration rollers 14 begin to rotate in synchronization with the toner image formed on the intermediate transfer belt 8 as described below, and the recording material S is transported along the transport path 600 to the secondary transfer section T2.

Note that, although only one cassette 12 is shown here, multiple cassettes 12 may be arranged to accommodate recording materials S of different sizes and thicknesses, in which case recording material S may be selectively transported to the transport path 600 from one of the multiple cassettes 12. Also, instead of recording material S accommodated in the cassette 12, recording material S placed on a manual feed section (not shown) may be transported to the transport path 600.

[Image forming unit]
The four image forming units PY, PM, PC, and PK included in the image forming apparatus 100 have substantially the same configuration, except for the different developing colors. Therefore, the black image forming unit PK will be described here as a representative, and descriptions of the other image forming units PY, PM, and PC will be omitted.

As shown in FIG. 2, the image forming unit PK is provided with a cylindrical photosensitive drum 1 as a photosensitive member. The photosensitive drum 1 is driven to rotate in the direction of the arrow R1 in the figure. Around the photosensitive drum 1, a charging device 2, an exposure device 3, a developing device 4, a primary transfer roller 5, and a drum cleaning device 6 are arranged.

The process of forming, for example, a full-color image by the image forming apparatus 100 will be described. First, when the image forming operation is started, the surface of the rotating photosensitive drum 1 is uniformly charged by the charging device 2. The charging device 2 is, for example, a corona charger that irradiates charged particles associated with corona discharge to charge the photosensitive drum 1 to a uniform negative polarity dark potential. Next, the photosensitive drum 1 is scanned and exposed by laser light L corresponding to an image signal emitted from the exposure device 3. As a result, an electrostatic latent image corresponding to the image signal is formed on the surface of the photosensitive drum 1. The electrostatic latent image formed on the photosensitive drum 1 is visualized by the toner (developer) contained in the developing device 4, becoming a visible image.

The toner image formed on the photosensitive drum 1 is primarily transferred to the intermediate transfer belt 8 at the primary transfer section T1, which is formed between the photosensitive drum 1 and the primary transfer roller 5 arranged with the intermediate transfer belt 8 sandwiched therebetween. At this time, a primary transfer bias is applied to the primary transfer roller 5. Toner remaining on the surface of the photosensitive drum 1 after the primary transfer is removed by the drum cleaning device 6.

Returning to FIG. 1, the above-mentioned operation is carried out in sequence at each of the yellow, magenta, cyan, and black image forming units PY to PK, and the four color toner images are superimposed on the intermediate transfer belt 8. After that, in accordance with the timing of the formation of the toner images, the recording material S stored in the cassette 12 is transported to the secondary transfer unit T2. Then, by applying a secondary transfer bias to the secondary transfer roller 10, the full-color toner image formed on the intermediate transfer belt 8 is secondarily transferred all at once to the recording material S.

The recording material S is then conveyed to the fixing device 11. The fixing device 11 has a fixing roller 11a arranged to rotate freely, and a pressure roller 11b which rotates while being pressed against the fixing roller 11a. The fixing roller 11a is rotated at a predetermined rotation speed (e.g., 400 mm/s) by a drive motor (not shown) while being pressed against the pressure roller 11b (e.g., a pressure of about 784 N (about 80 kgf)). A halogen heater 11c is arranged inside the fixing roller 11a, and the fixing device 11 can heat the recording material S by raising the surface temperature of the fixing roller 11a (e.g., 180°C) with this halogen heater 11c.

The fixing device 11 heats and pressurizes the recording material S on which the toner image is formed by sandwiching and conveying the recording material S on which the toner image is formed in the fixing nip T3 formed by the fixing roller 11a and the pressure roller 11b, thereby fixing the toner image to the recording material S. That is, the toner of the toner image formed on the recording material S is melted and mixed by heating and pressing, and is fixed to the recording material S as a full-color image. In this way, a series of image formation processes is completed. Then, the recording material S on which the toner image is fixed is conveyed to the recording material cooling device 20 by the conveying device 90. The conveying device 90 conveys the recording material S from the fixing device 11 to the recording material cooling device 20 by rotating the belt carrying the recording material S at a predetermined rotation speed (for example, 400 mm/s) by air adsorption, for example. The recording material cooling device 20 cools the recording material S conveyed by the conveying device 90. The temperature of the recording material S is, for example, about 90° C. before being cooled by the recording material cooling device 20, but is reduced to about 60° C. by the recording material cooling device 20. The recording material cooling device 20 will be described later (see FIG. 3 to FIG. 4(b)).

In this embodiment, the conveying path 600 has a reversing conveying section 600a that reverses the recording material S cooled by the recording material cooling device 20 and conveys it again to the image forming sections PY, PM, PC, and PK for double-sided printing. That is, in the case of single-sided printing, the recording material S with the toner image fixed on the first side (front side) is cooled by the recording material cooling device 20, then discharged outside the machine and stacked on the stacking unit 60. On the other hand, in the case of double-sided printing, the recording material S with the toner image fixed on the first side (front side) is cooled by the recording material cooling device 20, then reversed by the reversing conveying section 600a and conveyed to the conveying path 600, where the toner image is fixed to the second side (back side). The recording material S with the toner image fixed on the second side is cooled by the recording material cooling device 20, then discharged outside the machine and stacked on the stacking unit 60.

[Recording Material Cooling Device]
Next, the recording material cooling device 20 of this embodiment will be described with reference to Fig. 3 to Fig. 4B. The recording material cooling device 20 of this embodiment is a belt-cooling type cooling device. As shown in Fig. 3, the recording material cooling device 20 has an endless first belt 21 and an endless second belt 25 that conveys the recording material S by pinching it with the first belt 21. Both the first belt 21 and the second belt 25 are endless belts formed of, for example, a high-strength polyimide resin, with a thickness of 100 µm and a belt circumference of 942 mm.

As shown in FIG. 3, the first belt 21 is stretched across a number of first belt tension rollers (22a to 22d), and at least one of the first belt tension rollers (22a to 22d) is rotated by a drive motor (not shown). In the case of this embodiment, for example, roller 22d is rotated by a drive motor (not shown), causing the first belt 21 to move in the direction of arrow Q in the figure. Roller 22d as a drive roller has, for example, a rubber layer with a thickness of 1 mm on its surface, and is formed with an outer diameter of φ40 mm.

The roller 22b as the second roller is a steering roller that is arranged to be able to tension the first belt 21 together with the roller 22c by contacting the inner peripheral surface of the first belt 21, and controls the deviation of the first belt 21 in the width direction (the direction of the rotation axis of the roller 22c). The roller 22b has a rubber layer with a thickness of 1 mm on the surface, and the meandering of the first belt 21 can be controlled by performing a steering operation to turn the steering angle with respect to the roller 22c as the first roller. The roller 22b is steered by the steering mechanism 81. The steering mechanism 81 holds a roller holder 81a that holds the roller 22b and can swing around the center of the width direction as the swing center, and a spring 81b as a biasing means that biases the roller 22b held by the roller holder 81a toward the first belt 21. For example, the roller holder 81a has a bearing (not shown) that supports the rotation shaft of the roller 22b, and this bearing is biased by the spring 81b. The spring 81b is a fixed spring that can urge the roller 22b with a force that causes the tension of the first belt 21 to be, for example, about 39.2 N (about 4 kgf). The roller holder 81a is held so that it can swing around a swing center axis that intersects with the rotation axis of the roller 22b.

On the inner periphery of the first belt 21, in addition to a plurality of first belt tension rollers (22a to 22d) and a steering mechanism 81, a heat sink 30, a scraper 70, and a collection box 71 are provided. The heat sink 30, the scraper 70, and the collection box 71 will be described later.

On the other hand, the second belt 25 as a conveying member (belt-shaped member) is stretched over a plurality of second belt tension rollers (26a to 26d) and abuts against the outer peripheral surface of the first belt 21. In this embodiment, the second belt 25 abuts against the first belt 21 from below in the direction of gravity. The second belt 25 abuts against the outer peripheral surface of the first belt 21 to form a cooling nip portion T4 for cooling the recording material S on which the toner image is formed while conveying it. In this embodiment, the roller 26d is pressed by the roller 22d at, for example, about 49 N (about 5 kgf). Although not shown in the figure, the roller 26d is connected to a drive motor that drives the roller 22d via a drive gear, and the second belt 25 moves in the direction of the arrow R in the figure by being rotated by this drive motor. That is, the second belt 25 moves (rotates) together with the first belt 21. Roller 26b is a steering roller that controls the shift in the width direction of second belt 25 (the direction of the rotation axis of roller 26c), and performs a steering operation to turn the steering angle of roller 26c around the center of the width direction to control the meandering of second belt 25. That is, roller 26b is steered by a steering mechanism 82 similar to the steering mechanism 81 described above.

On the inner periphery of the second belt 25, multiple pressure rollers are provided to press the second belt 25 toward the heat sink 30 (described later) disposed on the inner periphery of the first belt 21. In this embodiment, as an example, in the recording material conveying direction (the direction of the arrow R in the figure), the pressure roller 26e is provided on the downstream end side of the cooling nip portion T4, and the pressure roller 26f is provided on the upstream end side of the cooling nip portion T4. These pressure rollers 26e and 26f press the second belt 25 with a pressure of, for example, 9.8 N (1 kgf), and the first belt 21 is more reliably abutted against the heat sink 30 via the second belt 25.

Note that, although an example in which both the first belt 21 and the second belt 25 are driven has been shown here, this is not limiting. For example, only the first belt 21 may be driven so that the second belt 25 follows the first belt 21, or only the second belt 25 may be driven so that the first belt 21 follows the second belt 25.

[heat sink]
A heat sink 30 for cooling the first belt 21 is disposed on the inner periphery of the first belt 21. In the present embodiment, the heat sink 30 is in contact with the inner periphery of the first belt 21, which is in contact with the recording material S on the side on which the toner image is formed by the fixing device 11. That is, the recording material S on which the toner image is fixed is sandwiched between the first belt 21 and the second belt 25, and is transported in the recording material transport direction (the direction of the arrow R in the figure) according to the rotation of these belts. At that time, the recording material S passes through a cooling nip portion T4, which is a nip portion formed by the contact of the first belt 21 and the second belt 25. In the present embodiment, the first belt 21, which forms the cooling nip portion T4, is cooled by the heat sink 30. In order to efficiently cool the recording material S, the heat sink 30 is in contact with the inner periphery of the first belt 21 at a location where the cooling nip portion T4 is formed by the first belt 21 being stretched by a plurality of first belt stretching rollers (22a to 22d). When the recording material S passes through the cooling nip portion T4, the temperature of the recording material S is reduced by the first belt 21 cooled by the heat sink 30.

The heat sink 30 as a cooling member is a heat dissipation plate formed of a metal such as aluminum. The heat sink 30 has a heat receiving portion 30a for contacting the first belt 21 to take heat from the first belt 21, a heat dissipation portion 30b for dissipating heat, and a fin base 30c for conducting heat from the heat receiving portion 30a to the heat dissipation portion 30b. The heat dissipation portion 30b is formed of a large number of heat dissipation fins in order to increase the contact area with the air and promote efficient heat dissipation. For example, the heat dissipation fins are set to a thickness of 1 mm, a height of 100 mm, and a pitch of 5 mm, and the fin base 30c is set to a thickness of 10 mm. In addition, a cooling fan 40 is provided to blow air toward the heat sink 30 (specifically, the heat dissipation portion 30b) in order to forcibly cool the heat sink 30 itself. The air volume of the cooling fan 40 is set to, for example, 2 m ³ /min.

[scraper]
In addition, on the inner periphery of the first belt 21, a scraper 70 as a removing member is disposed downstream of the heat sink 30 with respect to the moving direction of the first belt 21 (the direction of the arrow Q in the figure). In the case of this embodiment, the scraper 70 is provided so as to be located between the downstream of the roller 22c and the upstream of the roller 22b with respect to the moving direction of the first belt 21. The scraper 70 is a film-like sheet member formed, for example, of a PET sheet having a thickness of 0.1 mm, with a length that contacts at least the range through which the recording material S passes in the width direction of the first belt 21 perpendicular to the thickness direction and the rotation direction of the first belt 21. The scraper 70 is provided so as to contact the first belt 21 from the counter direction with respect to the moving direction of the first belt 21. Since such a scraper 70 has flexibility, it can maintain a state of contacting the first belt 21 by following the movement of the moving (rotating) first belt 21.

The scraper 70 is provided so as to be capable of cleaning the first belt 21 by removing from the first belt 21 any adhesions, including wear powder and paper powder, that are attached to the first belt 21. That is, as described above, the heat sink 30 is in contact with the inner peripheral surface of the first belt 21, and as the first belt 21 rotates, the inner peripheral surface of the first belt 21 is rubbed against the heat sink 30. As a result, the first belt 21 is scraped by the heat sink 30, and wear powder (also called scraping powder) of the belt may be generated. This wear powder adheres to the first belt 21 and is carried as an adhesion together with the paper powder, etc., and tends to accumulate at the upstream end of the heat sink 30. When the amount of the accumulated adhesions increases, some of the accumulated adhesions may get between the heat sink 30 and the first belt 21, which may increase the thermal resistance and reduce the cooling performance of the recording material S.

In order to suppress the generation of the above-mentioned wear powder, a belt formed of a polyimide resin containing, for example, polytetrafluoroethylene (PTFE) filler is used as the first belt 21. The PTFE filler content is, for example, about 5% by weight. When the polyimide resin of the base material contains PTFE filler, the friction resistance with the heat sink 30 decreases, so the first belt 21 containing PTFE filler is less likely to be scraped by the heat sink 30 than when it does not contain PTFE filler. However, even if a belt containing PTFE filler is used, wear powder of the belt can still be generated. This wear powder is difficult to adhere to the first belt 21 because it contains PTFE filler, but even such wear powder can adhere to the first belt 21 when it passes through the sliding surface between the heat sink 30 and the first belt 21. Therefore, as the use time of the first belt 21 increases, the amount of adhesion including wear powder that accumulates at the upstream end of the heat sink 30 increases. Therefore, in order to remove the deposits adhering to the first belt 21 from the first belt 21, as described above, a scraper 70 is disposed downstream of the heat sink 30 in the rotation direction of the first belt.

Below the scraper 70 in the direction of gravity, a collection box 71 is arranged to collect the deposits scraped off the first belt 21 by the scraper 70. The collection box 71 is open at the top in the direction of gravity, and is arranged so that the deposits can be received from the opening upstream in the movement direction of the first belt 21 from the contact point between the scraper 70 and the first belt 21. The collection box 71 will be described in detail later (Figures 5 to 6(b)). The scraper 70 is fixed to the collection box 71 by, for example, double-sided tape.

The first belt 21 described above is worn by being scraped off by the heat sink 30 as described above, and may deteriorate over time. The second belt 25, which is not provided with the heat sink 30, wears slower than the first belt 21, but wears with use and may deteriorate over time. Therefore, in order to enable an operator to replace the worn or deteriorated first belt 21 or second belt 25, the first belt 21 and the second belt 25 are provided so as to be freely inserted and removed from the upper frame 62 and the lower frame 63 (see Figures 4(a) and 4(b) described later) of the recording material cooling device 20, respectively. However, when an operator replaces the first belt 21 or the second belt 25, it is difficult to insert and remove the belts if the first belt 21 and the second belt 25 are in contact with each other. Therefore, the first belt 21 and the second belt 25 are provided so as to be movable relative to each other so that they can be changed between a contact state in which the first belt 21 and the second belt 25 are in contact with each other and a separated state in which the first belt 21 and the second belt 25 are separated (open).

[Contact/separation mechanism]
A mechanism for relatively moving the first belt 21 and the second belt 25 (called a contact/separation mechanism) will be described. FIGS. 4A and 4B are views of the recording material cooling device 20 as viewed from the downstream side in the recording material conveying direction. In FIGS. 4A and 4B, the right side is the "front side" of the image forming apparatus 100 (recording material cooling device 20), and the left side is the "rear side" of the image forming apparatus 100 (recording material cooling device 20). In the present embodiment, a contact/separation mechanism 610 is provided so that an upper frame 62 in which a scraper 70 and a collection box 71 are arranged can be swung upward in the direction of gravity. The upper frame 62 is swung so that one end side (rear side) in the width direction is moved around the swing center to move the other end side (front side). In this embodiment, the contact/separation mechanism 610, which is a support portion, is mainly composed of a swing shaft 62a, a hook member 64, a pin 65, and a compression spring 66.

As shown in FIG. 4(a) and FIG. 4(b), the recording material cooling device 20 of this embodiment is roughly divided into an upper frame 62 and a lower frame 63. The upper frame 62 as a holder rotatably holds the above-mentioned first belt tension rollers (22a to 22d), and also holds a heat sink 30 and a collection box 71. The scraper 70 is held in the collection box 71. On the other hand, the lower frame 63 rotatably holds the above-mentioned second belt tension rollers (26a to 26d) and pressure rollers 26e and 26f. The upper frame 62 and the lower frame 63 are connected to be able to swing about a swing shaft 62a provided at one end side (back side) in the width direction as the swing center. The first belt 21 is provided so as to be freely inserted and removed from the upper frame 62 from the other end side (front side) in the width direction, and the second belt 25 is provided so as to be freely inserted and removed from the other end side (front side) in the width direction of the lower frame 63.

A hook member 64 is provided on the other end (front side) of the upper frame 62 in the width direction, and a pin 65 is provided on the other end (front side) of the lower frame 63 in the width direction. A compression spring 66 is arranged on one end of the lower frame 63 in the width direction to bias the upper frame 62 upward in the direction of gravity. The hook member 64 is provided with a gripping portion 67, and an operator can hold the gripping portion 67 from the front side of the recording material cooling device 20 and rotate the hook member 64 to engage the hook member 64 with the pin 65 or to release the engagement between the hook member 64 and the pin 65. As shown in FIG. 4A, when the hook member 64 is engaged with the pin 65, the first belt 21 and the second belt 25 are in contact with each other. The operator pushes the upper frame 62 down toward the lower frame 63 against the force of the compression spring 66 to engage the hook member 64 with the pin 65. The spring force of the compression spring 66 only needs to be set to a value according to the weight of the upper frame 62, and in this embodiment, it is set to a value that allows the worker to engage the hook member 64 with the pin 65 with a force of approximately 10 N.

When replacing the first belt 21 or the second belt 25, the worker releases the engagement between the hook member 64 and the pin 65. When the engagement between the hook member 64 and the pin 65 is released, the upper frame body 62 is swung upward by the compression spring 66 as shown in FIG. 4(b). At this time, the first belt tension rollers (22a to 22d), the first belt 21, the heat sink 30, the scraper 70, and the collection box 71 are moved integrally with the upper frame body 62. The upper frame body 62 is then positioned in a predetermined position by being stopped from swinging by a stopper (not shown). In this way, the upper frame body 62 swings relative to the lower frame body 63, and the first belt 21 and the second belt 25 are separated from each other. In this embodiment, the collection box 71 is swung together with the upper frame 62 so that it can move to a state where it is not tilted with respect to the horizontal plane when the belt is in contact with the box, and to a state where it is tilted with respect to the horizontal plane when the belt is in a separated state.

Here, the configuration in which the first belt 21 and the second belt 25 are moved toward and away from each other by the above-mentioned contact mechanism 610 is used when replacing the first belt 21 or the second belt 25, but the contact mechanism 610 may be used in other cases. For example, when a so-called jam occurs in which the recording material S is stuck between the cooling nip portion T4 between the first belt 21 and the second belt 25, the contact mechanism 610 may be used to separate the first belt 21 and the second belt 25. In this case, since the gripping portion 67 is located on the front side as described above, the user can remove the stuck recording material S from the front side of the recording material cooling device 20, which is easy to work with. In this case, it is sufficient that the upper frame 62 swings relative to the lower frame 63 to bring the first belt 21 and the second belt 25 into a separated state. Therefore, even when removing the recording material S stuck between the first belt 21 and the second belt 25, the collection box 71 swings together with the upper frame 62, so that the collection box 71 is inclined relative to the horizontal plane. In this embodiment, the state in which the cooling nip T4 is formed by the first belt 21 and the second belt 25 is the first position of the upper frame 62. The state in which the second belt 25 is swung relative to the first belt 21 (the first belt 21 is tilted) when removing the recording material S that has accumulated in the cooling nip T4 is the second position of the upper frame 62. Here, the state in which the cooling nip T4 is formed means a state in which the recording material S can be transported by the recording material cooling device 20.

[Collection box]
Next, the collection box 71 of this embodiment will be described with reference to Fig. 3 and Fig. 5 to Fig. 6B. In the following description, the other end side in the width direction of the upper frame 62 (the right front side in Fig. 5 to Fig. 6B) is also referred to as the "front (or front)" of the image forming apparatus 100 (recording material cooling device 20). Also, one end side in the width direction of the upper frame 62 is also referred to as the "rear" of the image forming apparatus 100 (recording material cooling device 20) (the left rear side in Fig. 5 to Fig. 6B).

As shown in FIG. 5, the collection box 71 as a receiving container is provided along the longitudinal direction of the scraper 70 (the width direction of the first belt 21, the direction of the rotation axis) and collects the deposits removed from the inner surface of the first belt 21 by the scraper 70. The collection box 71 of this embodiment has a wall surface portion 71c on the outer side of the contact area Z where the scraper 70 contacts the first belt 21 in the width direction (longitudinal direction of the scraper 70). The wall surface portion 71c is located downstream of the ridge line portion 70a of the scraper 70 that contacts the first belt 21 at least in the movement direction of the first belt 21 (arrow Q direction in the figure) and is located on one end side of the first belt 21 in the width direction from the contact area of the ridge line portion 70a. In addition, the wall surface portion 71c is provided so that the upstream side of the ridge line portion 70a in the movement direction is located on one end side of the first belt 21 in the width direction from the contact area of the ridge line portion 70a. This wall portion 71c holds back the stored deposits when the collection box 71 tilts due to the swinging of the upper frame 62, so that even if the collection box 71 tilts due to the swinging of the upper frame 62, the deposits can be prevented from spilling out of the collection box 71.

In this embodiment, the collection box 71 is replaced when it contains a predetermined amount of deposits. The predetermined amount here refers to the amount of deposits that are collected in the collection box 71 when the first belt 21 rotates a predetermined number of times (e.g., 1,500,000 rotations). The timing for replacing the collection box 71 is the same as the timing for replacing the first belt 21.

In this embodiment, the amount of deposits collected when the first belt 21 rotates, for example, 1,500,000 times is set as the allowable amount that can be collected by the collection box 71 when the recording material cooling device 20 is used normally. Therefore, the wall surface portion 71c is provided so as to prevent leakage of deposits when the amount of deposits collected in the collection box 71 is equal to or less than the allowable amount even when the upper frame body 62 is swung. In this embodiment, when the collection box 71 collects deposits equal to or less than a predetermined amount (the allowable amount that can be collected by the collection box 71), the purpose is to prevent deposits from overflowing from the collection box 71 even when the upper frame body 62 is swung within the range of normal use. Therefore, outside the range of normal use, deposits may overflow from the collection box 71. Here, outside the range of normal use means, for example, when an amount of deposits exceeding the allowable amount is collected in the collection box, or when the upper frame body 62 is swung more violently than in normal use.

In this embodiment, the ridge portion 70a, which is the contact portion of the scraper 70 that contacts the first belt 21 in the movement direction of the first belt 21, is provided so as to be located inside the collection box 71 in the movement direction of the first belt 21 (the direction of the arrow Q in the figure). In other words, the scraper 70 is attached to the collection box 71 so that the ridge portion 70a is located between the upstream wall 70b and downstream wall 70c of the collection box 71 in the direction of the arrow Q. In this embodiment, the distance between the upstream wall 70b and downstream wall 70c in the direction of the arrow Q is 20 to 30 mm.

The depth from the upper end 71e surrounding the opening of the collection box 71 to the bottom surface 71d is formed so that the downstream side in the moving direction of the first belt 21 (arrow Q direction in the figure) is deeper than the upstream side. That is, the downstream wall 70c of the collection box 71 in the arrow Q direction of the first belt 21 is higher than the upstream wall 70b. In this embodiment, the height of the downstream wall 70c in the arrow Q direction is 2 to 4.5 mm. The collection box 71 has an opening that receives deposits including wear powder scraped off by the scraper 70, and is disposed with a predetermined gap between the upper end 71e surrounding the opening and the inner surface of the first belt 21. Here, the opening of the collection box 71 is formed by the upper end 71e that connects the upper ends of the wall surface portions 71b, 71c and the walls 70b, 70c, as shown in FIG. 5.

Furthermore, inside the collection box 71, a number of partition ribs 71a are formed as partitions that divide the internal space in which the deposits are stored into a number of compartments in the longitudinal direction of the scraper 70. In this embodiment, five partition ribs 71a are provided at equal intervals in the longitudinal direction, dividing the interior of the collection box 71 into six storage chambers capable of storing deposits. These partition ribs 71a are higher in height from the bottom surface 71d of the collection box 71 downstream than upstream in the movement direction of the first belt 21 (arrow Q direction in the figure) in accordance with the depth of the collection box 71. In this way, in each storage chamber separated by the partition ribs 71a, a larger amount of deposits can be stored downstream in the movement direction of the first belt 21 (arrow Q direction in the figure) than upstream.

In this way, the collection box 71, which has an opening for collecting the deposits scraped off by the scraper 70, has multiple partition ribs 71a. This allows the amount of deposits collected by the collection box 71 to be increased compared to when the collection box 71 is configured only with the wall portions 71b and 71c without the partition ribs 71a. This is because, as described above, the amount of deposits that move with the rotation of the upper frame 62 can be increased by blocking the deposits with the wall portion 71c and multiple partition ribs 71a before they leak out from the wall portion 71c to the back side when the collection box 71 is tilted, rather than blocking the deposits only with the wall portion 71c.

In addition, the inventors of the present application conducted experiments under the following conditions 1 and 2 using the above-mentioned collection box 71 to investigate the belt separation operation and the accumulation state of the deposits in the collection box. In condition 1, the recording material cooling device 20 is operated continuously for 8 hours per day, and the above-mentioned belt separation operation is not performed even once. The accumulation state of the deposits in the collection box 71 when the experiment was conducted under condition 1 is shown in FIG. 6(a). On the other hand, in condition 2, the recording material cooling device 20 is operated continuously for 8 hours per day like in condition 1, but unlike condition 1, the above-mentioned belt separation operation is performed about once every 7 days. The accumulation state of the deposits in the collection box 71 when the experiment was conducted under condition 2 is shown in FIG. 6(b). The inventors of the present application conducted experiments under these conditions 1 and 2 to investigate the number of days it took for the deposits to leak out of the collection box 71.

When the experiment was conducted under condition 1, it took 111 days for the deposits to leak out of the collection box 71. That is, as shown in FIG. 6(a), the deposits W (indicated by thick diagonal lines in the figure) pile up in a mountain shape almost directly below the ridge line 70a, which is the area where the scraper 70 contacts the first belt 21. In the case of condition 1, the deposits W pile up only directly below the ridge line 70a, and the capacity of the collection box 71 cannot be fully utilized.

In contrast, when the experiment was conducted under condition 2, it took 139 days for the deposits to leak out of the collection box 71. For example, when a user lifts the upper frame 62 upward and performs a rocking motion to remove the accumulated recording material S, the collection box 71 tilts so that the front wall surface 71b (the other end wall surface) is located higher in the direction of gravity than the back wall surface 71c. Also, from the top perspective when the upper frame 62 (see FIG. 4A) is lifted upward, the rocking is stopped at a predetermined position by a stopper (not shown), and at that time, a certain shock is applied to the collection box 71. In this way, when the collection box 71 is tilted and a certain shock is applied, the deposits W that were stored in a pile as shown in FIG. 6A collapse to the back side. Then, as shown in FIG. 6B, the collapsed deposits W are blocked by the wall surface portion 71c and the partition rib 71a, and are moved along the partition rib 71a from the upstream side to the downstream side in the moving direction of the first belt 21 while being leveled. In this way, in this embodiment, the pile of deposits W that is piled up in a mountain shape just below the ridge portion 70a is collapsed, and the deposits W can be stored while being pushed toward the deeper downstream space, that is, the downstream space with a larger storage capacity. In other words, by moving the deposits W to the base side (fixed side) of the scraper 70, the area just below the scraper 70 in the collection box 71 is effectively utilized.

6B, if the recording material cooling device 20 is operated continuously, the deposits W start to accumulate again near the ridge portion 70a of the scraper 70. Then, when the user performs a rocking operation to lift the upper frame 62 upward when removing the stuck recording material S, the pile of deposits W is broken down and accumulated in each storage chamber each time the collection box 71 is tilted. In addition, the wall portion 71c prevents the deposits W from flowing to the back side and overflowing from the collection box 71 when the collection box 71 is tilted. Furthermore, by dividing the inside of the collection box 71 into multiple storage chambers by the partition rib 71a, it is possible to store more deposits while preventing the deposits W from flowing to the back side and overflowing from the collection box 71 when the collection box 71 is tilted. In this way, by tilting the collection box 71 and breaking up the pile of adhering matter W, the adhering matter W accumulates only in one part of the collection box 71, preventing the adhering matter W from spilling out of the collection box 71.

As described above, in this embodiment, the recovery box 71 is swung together with the upper frame 62, so that when the first belt 21 and the second belt 25 are in a separated state, the recovery box 71 is inclined with respect to the horizontal plane. The recovery box 71 has a wall surface portion 71c on the outer side of the contact area Z of the first belt 21 where the scraper 70 is in contact with in the width direction. In addition, inside the recovery box 71, a plurality of partition ribs 71a are formed to divide the internal space that stores the deposits including wear powder into a plurality of parts in the longitudinal direction. As a result, when the user tilts the recovery box 71 with the swinging operation of the upper frame 62 when removing the accumulated recording material S, the deposits W that move toward the rotation center side of the upper frame 62 inside the recovery box 71 can be prevented from overflowing from the rotation center side of the recovery box 71. Therefore, it is possible to prevent the deposits W from flowing out into the inside of the recording material cooling device 20 and causing the inside of the device to become dirty. In addition, since the deposits in the collection box 71 are easily dispersed and distributed throughout the collection box 71, the storage space of the collection box 71 can be used more efficiently. In this way, the collection box 71 can store a larger amount of deposits, thereby reducing the frequency with which workers have to remove deposits from the collection box 71.

The collection box 71 may be provided so as to be freely inserted and removed from the other end side in the width direction of the upper frame 62 (the left side in Figs. 4(a) and 4(b)). It is also preferable that the worker be able to insert and remove the collection box 71 only when the first belt 21 and the second belt 25 are in contact with each other as shown in Fig. 4(a). In other words, when in the contact state, the collection box 71 is released from the upper frame 62 without being tilted, which is advantageous because the attached matter is less likely to fall out of the collection box 71 when it is released.

Second Embodiment
Next, the recovery box of the second embodiment will be described with reference to Fig. 7(a) and Fig. 7(b). As shown in Fig. 7(a), the recovery box 72 of the second embodiment has wall portions 72b, 72c on the outer side of the contact area Z of the first belt 21 where the scraper 70 contacts in the width direction, similar to the recovery box 71 of the first embodiment (see Fig. 5). A plurality of partition ribs 72a are formed as partitions inside the recovery box 72, and the recovery box 72 is divided into six storage chambers. These partition ribs 72a are formed so that the height from the bottom surface portion 72d of the recovery box 72 is higher on the downstream side than on the upstream side in the moving direction.

Furthermore, unlike the collection box 71 (see FIG. 5), the collection box 72 is formed with a slanted partition rib 72a so that the downstream end of the movement direction is closer to the center of the swing than the upstream end when viewed from the movement direction of the first belt 21 (the direction of the arrow Q in the figure). When the worker performs a swinging motion to lift the upper frame 62 upward, the collection box 72 also tilts accordingly. Then, as shown in FIG. 7(b), the pile of deposits W that had been stored collapses toward the back, and the collapsed deposits W are blocked by the partition rib 72a. The partition rib 72a is formed with a slanted shape as described above. Therefore, the deposits W are likely to enter the area directly below the scraper 70. As a result, compared to the first embodiment, the area directly below the scraper 70 can be more effectively utilized to accumulate the deposits W.

When the number of days until the deposits leaked out of the collection box 72 was examined for the second embodiment, it was 187 days. This is longer than the experimental result (condition 2) of 139 days for the first embodiment. In other words, in the case of the second embodiment, the storage space in the collection box 72 can be used more efficiently than in the case of the first embodiment, and the frequency with which the worker removes the deposits W from the collection box 72 can be increased.

<Other embodiments>
In the above-described embodiments, the upper frame 62 is swung upward in the direction of gravity, but the present invention is not limited to this. The lower frame 63 may be swung downward in the direction of gravity relative to the upper frame 62 with the swing shaft 62a as the swing center. In this case, for example, the inclination direction of the partition rib 72a in FIG. 7(a) is reversed. With this configuration, the collection box 72 is tilted so that the side with the wall portion 72c moves downward in the direction of gravity as the lower frame 63 swings. In response to this, the piled up deposits W that were stored collapse on the front side, and the collapsed deposits W are blocked by the diagonally formed partition rib 72a and can enter the area directly below the scraper 70.

In the above-described embodiments, the recording material cooling device 20 is provided inside the device body 100A of the image forming device 100 (see FIG. 1), but this is not limiting. For example, the recording material cooling device 20 may be provided outside the device body 100A. FIG. 8 shows an example in which the recording material cooling device 20 is provided outside the device body 100A.

As shown in FIG. 8, an external cooling unit 101 is connected to the apparatus main body 100A as an external cooling device. The external cooling unit 101 is configured to be connectable to the image forming apparatus 100 as one of the peripheral devices (called optional units, etc.) that can be added later to expand the functions of the image forming apparatus 100. The external cooling unit 101 is arranged to cool the recording material S discharged from the apparatus main body 100A and to lower the temperature of the recording material S, which is higher than before fixing, to a predetermined temperature or lower. The external cooling unit 101 has the above-mentioned recording material cooling device 20 to cool the recording material S.

The recording material S cooled by the external cooling unit 101 is discharged from the external cooling unit 101 by the discharge roller 17 and loaded onto the loading unit 60. The loading unit 60 is provided so as to be freely attached and detached to the external cooling unit 101 and the image forming apparatus 100. That is, when the external cooling unit 101 is not connected to the image forming apparatus 100, the loading unit 60 is attached to the image forming apparatus 100 (see FIG. 1). Then, when the external cooling unit 101 is connected to the image forming apparatus 100, the loading unit 60 is removed from the image forming apparatus 100 by the user and replaced with the external cooling unit 101.

In addition, multiple external cooling units 101 may be connected as peripheral devices. By increasing the number of external cooling units 101 that are connected, an operator can easily improve the cooling capacity of the recording material S of an existing image forming apparatus 100.

In addition, in each of the above-described embodiments, the entire wall surface portion 71c is configured to be located outside the contact area Z of the scraper 70 with the first belt 21, but other configurations may be used as long as the deposits W scraped off by the scraper 70 can be collected. For example, the wall surface portion 71c may be configured to be located inside the width of the contact area Z of the scraper 70 in the width direction of the first belt 21. Figures 9(a) to 9(c) show an example in which the wall surface portion 71b (the other end side wall surface portion) and a part of the wall surface portion 71c are arranged to overlap with the contact area Z of the scraper 70. Figure 9(a) is a cross-sectional view of the first belt 21 cut in the thickness direction at the position of the ridge portion 70a, which is the contact position between the first belt 21 and the scraper 70, viewed from the upstream side of the movement direction Q of the first belt 21. FIG. 9(b) is a diagram viewed from above in the vertical direction, and is an explanatory diagram showing the positional relationship between the ridge portion 70a of the scraper 70 and the wall portions 71b and 71c. Note that the partition rib 71a is not shown in FIG. 9(b) and FIG. 9(c).

9(a) and 9(b), at the position of the ridge portion 70a indicating the area where the scraper 70 abuts against the first belt 21, the wall portions 71b and 71c are partially located outside in the longitudinal direction of the collection box 71. Specifically, as shown in FIG. 9(b), the wall portion 71c is located downstream of the ridge portion 70a at least in the moving direction of the first belt 21 (direction of the arrow Q in the figure), and is located on one end side of the first belt 21 in the width direction from the abutment area Z of the ridge portion 70a. In addition, the wall portion 71c is provided in an oblique shape so as to overlap a part of the abutment area Z in the rotation axis direction upstream of the ridge portion 70a in the moving direction. On the other hand, the wall portion 71b is located downstream of the ridge portion 70a in the moving direction from the abutment area Z in the rotation axis direction. In addition, the wall surface portion 71b is provided in an oblique shape so as to overlap a part of the contact area Z in the rotation axis direction upstream of the ridge line portion 70a in the moving direction. Here, with respect to the moving direction of the first belt 21, the interval L1 between the upstream end of the wall surface portion 71b and the upstream end of the wall surface portion 71c is shorter than the contact area Z in the width direction. Also, with respect to the moving direction of the first belt 21, the interval L2 between the downstream end of the wall surface portion 71b and the downstream end of the wall surface portion 71c is longer than the contact area Z in the width direction. Even with this configuration, at the position of the ridge line portion 70a where the scraper 70 is in contact with the first belt 21, the wall surface portions 71b and 71c are located on the outside, so that the scraped off deposits W can be collected. Note that the wall surface portion 71b is inclined so that the upstream end of the wall surface portion 71b is located in a direction away from the ridge line portion 70a in the width direction, and the upstream end is located in a direction approaching the ridge line portion 70a. This allows the area downstream of the ridge 70a for collecting the deposits W to be expanded.

9(b), the wall surface portion 71b and the wall surface portion 71c are inclined in different directions. However, as shown in FIG. 9(c), the wall surface portion 71b and the wall surface portion 71c may be inclined in the same direction. That is, the wall surface portion 71b is located upstream of the ridge portion 70a in the moving direction on the other end side of the first belt 21 in the rotation axis direction from the contact area Z, and is overlapped with a part of the contact area Z in the rotation axis direction downstream of the ridge portion 70a in the moving direction. Thus, in this configuration, the upstream end of the wall surface portion 71c in the moving direction is located inside the ridge portion 70a in the width direction, and the downstream end of the wall surface portion 71b is located inside the ridge portion 70a in the width direction. Even with this configuration, the wall surface portions 71b and 71c are located outside at the position of the ridge portion 70a where the scraper 70 is in contact with the first belt 21, so the scraped off deposits W can be collected.

In each of the above-described embodiments, the scraper 70 is shown as an example of a removal member, but other removal members such as a fur brush or nonwoven fabric may be used as long as they are capable of removing deposits from the inner circumferential surface of the belt.

11...fixing device, 20...recording material cooling device, 21...belt (first belt), 22a-22d...rollers (first belt tension rollers), 25...conveying member (belt-shaped member, second belt), 30...cooling member (heat sink, heat sink), 62...holding body (upper frame), 70...removing member (scraper), 70a...contact portion (ridge line portion), 71 (72)...receiving container (recovery box), 71a (72a)...partition portion (partition rib), 71b (72b)...other end side wall portion, 71c (72c)...wall portion, 71d...bottom portion, 100...image forming device, 500...image forming unit, 610...support portion (contact/separation mechanism), S...recording material, T4...nip portion (cooling nip portion)

Claims (14)

A recording material cooling device that cools a recording material that has passed through a fixing device that fixes a toner image on the recording material by heating,
Belt and
A plurality of rollers around which the belt is stretched;
a cooling section that contacts an inner circumferential surface of the belt and cools the belt;
a conveying section that contacts an outer peripheral surface of the belt and forms a nip section through which a recording material having a toner image formed thereon is conveyed;
a removal unit for removing deposits attached to an inner circumferential surface of the belt;
A receiving container having an opening for receiving the deposit removed by the removal unit;
a holding section that holds the plurality of rollers, the cooling section, and the receiving container, and is capable of swinging between a first position where the nip section is formed between the belt and the conveying section, and a second position where the belt is separated from the conveying section,
the plurality of rollers includes a drive roller that drives the belt,
a pivot center of the holding portion extends in a direction intersecting a rotation axis direction of the drive roller and a vertical direction,
the receiving container has a bottom surface portion extending in a rotation axis direction of the drive roller to receive the deposit, and a first wall surface portion and a second wall surface portion at both ends of the bottom surface portion in the rotation axis direction ,
a partition wall portion that divides the inside of the receiving container into a plurality of storage chambers between the first wall surface portion and the second wall surface portion in the direction of the rotation axis, the partition wall portion having a first partition wall portion located on the first wall surface portion side of a center between the first wall surface portion and the second wall surface portion, and a second partition wall portion located on the second wall surface portion side of a center between the first wall surface portion and the second wall surface portion,
the first partition portion and the second partition portion are both formed obliquely so that a downstream end side in the moving direction of the belt is closer to a swing center than an upstream end side.
A recording material cooling device comprising: The first wall surface portion is provided such that at least a part of the first wall surface portion located downstream of a contact portion of the removal portion that contacts the belt in the moving direction of the belt is located on one end side of the belt in the rotation axis direction relative to a contact area of the contact portion.
2. The recording material cooling device according to claim 1, The first wall surface portion is provided such that a part of the first wall surface portion located upstream of a contact portion of the removal portion that contacts the belt in a moving direction of the belt is located on one end side of the belt in the rotation axis direction relative to a contact area of the contact portion.
2. The recording material cooling device according to claim 1, The first wall surface portion is obliquely provided such that a part of the first wall surface portion located upstream of a contact portion of the removal portion that contacts the belt in the moving direction of the belt overlaps with a part of a contact area of the contact portion in the rotation axis direction.
2. The recording material cooling device according to claim 1, The second wall surface portion is provided such that at least a part of the second wall surface portion located downstream of a contact portion of the removal portion that contacts the belt in the moving direction of the belt is located on the other end side of the belt in the rotation axis direction relative to a contact area of the contact portion.
3. The recording material cooling device according to claim 2 , a distance between the first wall surface portion and the second wall surface portion in the rotation axis direction is longer than a length of a contact portion of the removal portion that contacts the belt;
2. The recording material cooling device according to claim 1 , The receiving container is formed so that the downstream side in the moving direction of the belt is deeper than the upstream side,
the partition portion has a height from the bottom surface portion that is greater on a downstream side than on an upstream side in the moving direction;
2. The recording material cooling device according to claim 1 , The removal unit is held in the receiving container.
8. The recording material cooling device according to claim 1 , wherein the recording material cooling device is a cooling device for cooling a recording material. The cooling unit is a heat sink that comes into contact with the belt and dissipates heat.
9. The recording material cooling device according to claim 1 , wherein the recording material cooling device is a cooling device for cooling a recording material. The conveying unit is a belt-shaped member.
10. The recording material cooling device according to claim 1, a support portion that supports the holding portion so that the holding portion can swing between the first position and the second position,
a pivot center of the support portion is disposed on a rear side of the recording material cooling device relative to the nip portion in the direction of the rotation axis;
2. The recording material cooling device according to claim 1, When the holding portion is in the first position, the first wall portion is disposed at a position closer to a swing center of the holding portion than the bottom portion of the receiving container in the direction of the rotation axis.
2. The recording material cooling device according to claim 1, an upper unit in which the belt, the plurality of rollers, the cooling unit, the removing unit, the receiving container, and the holding unit are disposed;
a lower unit in which the conveying unit is disposed;
a locking portion that is provided on the opposite side of the pivot center of the holding portion in the direction of the rotation axis and that locks the upper unit to the lower unit when the holding portion is in the first position,
2. The recording material cooling device according to claim 1, an image forming unit that forms a toner image on a recording material;
a fixing unit that fixes the toner image formed by the image forming unit by heating;
a recording material cooling device according to claim 1 , the recording material cooling device being provided downstream of the fixing unit in a recording material conveying direction and configured to cool the recording material that has passed through the fixing unit;
1. An image forming apparatus comprising:

Images