Image forming apparatus

Abstract

To suppress a reduction in the temperature inside a fixing device during carrying-in an object, compared with a configuration where an object is carried in from an opening of a fixing device.SOLUTION: An image forming apparatus comprises: a conveying mechanism that conveys a medium being an object along a conveyance path constituted by a conveying rail 410; a transfer unit that transfers an image to the medium on the conveyance path; and a fixing unit 200 that fixes the image to the medium. The fixing unit 200 has a heat source 210 that increases an internal temperature, and includes a shutter 201 as a carry-in port opening and closing member to which the medium having the image transferred thereto is carried in along the conveyance path, opens a carry-in port 201 when the medium is carried in, and closes the carry-in port when the medium has been carried in.SELECTED DRAWING: Figure 4

Description

[[Technical Field]]

[0001] The present invention relates to an image forming apparatus. [[Background Art]]

[0002] In recent years, images are sometimes printed on media having various thicknesses and shapes such as metal, glass, and tiles. The printing step includes a step of fixing an image formed on the printing surface of an object with an image forming material by applying heat treatment or pressure treatment.

[0003] Patent Document 1 discloses a method in which particles serving as an image forming material include thermosetting powder particles, and a particle image adhered to an object is heated by a heat source to be fixed. [[Prior Art Literature]] [[Patent Literature]]

[0004] [[Patent Document 1]] Japanese Patent No. 6900650 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0005] When heat fixing is performed inside a fixing device, it is required to suppress a decrease in temperature inside the fixing device when an object is carried into the fixing device.

[0006] An object of the present invention is to suppress a decrease in temperature inside a fixing device when an object is carried in, compared to a configuration in which the object is carried in through an opening of the fixing device. [[Means for Solving the Problem]]

[0007] The present invention according to claim 1 provides: a conveying unit that conveys an object along a conveying path; a transfer unit that transfers an image to the object on the conveying path; The device comprises a fixing unit having a heat source for raising the internal temperature, the object onto which the image has been transferred being transported along the transport path, and an opening / closing member for the opening that opens when the object is being transported and closes when the object is transported. 、 The fixing unit includes an outlet opening / closing member that opens an outlet from which the object is discharged after the fixing process of the image transferred to the object has been performed, and closes the outlet when the object has been discharged. The aforementioned outlet opening / closing member includes a cover portion that covers the heat source when the outlet is opened and exposes the heat source when the outlet opening / closing member closes the outlet. This is an image forming apparatus characterized by the following: The present invention according to claim 2 is The image forming apparatus according to claim 1, characterized in that when the loading port of the fixing unit is in its most open state, the height of the loading port is approximately the same as the height of the position where the transfer unit transfers an image onto the object. The present invention according to claim 3 is The image forming apparatus according to claim 2, wherein the loading opening / closing member of the fixing unit is a shutter that opens the loading opening by rising from the lower end of the loading opening, and the upper limit of the rise of the shutter is approximately the same height as the position in which the transfer unit transfers an image onto the object. [Effects of the Invention]

[0008] The book described in the claim According to the invention, compared to a configuration in which an object is loaded through an opening without an opening / closing mechanism, it is possible to suppress the decrease in temperature inside the fixing part when an object is loaded. [Brief explanation of the drawing]

[0009] [Figure 1] This diagram shows the configuration of an image forming apparatus to which this embodiment is applied. [Figure 2] This diagram shows the configuration of the transfer section. [Figure 3] These diagrams show the operation of the transport mechanism before image formation by the transfer unit begins. Figure 3(A) shows the height control process, Figure 3(B) shows the mechanism retracting to the preparation position after height control, and Figure 3(C) shows the state when image transfer by the transfer unit begins. [Figure 4] This diagram shows the configuration and operation of the fixing unit. [Figure 5] These diagrams illustrate the operation of each shutter in the fixing unit. Figure 5(A) shows the state when the media is being loaded, Figure 5(B) shows the state when the fixing process is being executed, and Figure 5(C) shows the state when the media is being unloaded. [Figure 6] This diagram shows the height restrictions at the entrance to the anchoring section. [Figure 7] This figure shows an example of using an air curtain as a means of opening and closing the exit. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described in detail below with reference to the attached drawings. The image forming apparatus of this embodiment is an image forming apparatus that uses digital printing. Digital printing methods include electrophotography and inkjet, but in this embodiment, the electrophotography method is assumed. In the electrophotography method, the transfer unit and the medium come into contact when an image is transferred to the medium. In this embodiment, the object to be printed is assumed to be a medium having various thicknesses and shapes, such as metal, glass, and tiles.

[0011] <Device configuration> Figure 1 shows the configuration of an image forming apparatus to which this embodiment is applied. The image forming apparatus 10 comprises a transfer unit 100, a fixing unit 200, a media attachment / detachment unit 300, and a transport mechanism 400. Although not specifically shown, the image forming apparatus 10 also comprises a control unit having one or more processors as computing means, memory as a work area for data processing, and a storage device for holding programs and data. The control unit may be a single unit that controls the operation of the entire image forming apparatus 10, or it may be provided individually for each of the transfer unit 100, fixing unit 200, transport mechanism 400, etc.

[0012] The transfer unit 100 is a unit that transfers an image formed of particles such as toner onto a medium 500. The fixing unit 200 is a unit that fixes the image transferred by the transfer unit 100 onto the surface of the medium 500 by heating the medium 500. The medium attaching / detaching unit 300 is a unit that allows a user of the image forming apparatus 10 to attach the medium 500 to a mounting table (described later) provided in the conveyance mechanism 400. The conveyance mechanism 400 is provided across the entire transfer unit 100, fixing unit 200, and medium attaching / detaching unit 300, and conveys the print-target medium 500 to each of the units 100, 200, and 300 as indicated by the arrow in FIG. 1.

[0013] The medium attaching / detaching unit 300 is a housing partially having an opening through which the medium 500 can be inserted and removed. As will be described in detail later, inside the medium attaching / detaching unit 300, there is a portion on one end side of a conveyance rail 410 that constitutes the conveyance mechanism 400, and a conveyance start position and a conveyance end position are set. In the present embodiment, the conveyance start position and the conveyance end position are set at the same location. In an initial state, a mounting table 420 that constitutes the conveyance mechanism 400 is disposed at the location of the conveyance rail 410 set as the conveyance start position and the conveyance end position. When a user inserts a jig 423 holding the medium 500 through the opening of the housing of the medium attaching / detaching unit 300 and mounts the jig onto the mounting table 420, the conveyance mechanism 400 becomes ready to convey the medium 500. After an image is transferred onto the medium 500 by the transfer unit 100 and a fixing process is performed by the fixing unit 200, the mounting table 420 carrying the medium 500 moves along the conveyance rail 410 and reaches the conveyance end position. In this state, the user detaches the jig 423 holding the medium 500 from the mounting table 420 and takes it out through the opening of the housing of the medium attaching / detaching unit 300.

[0014] <Configuration of Transfer Unit 100> FIG. 2 is a diagram showing the configuration of the transfer unit 100. The transfer unit 100 forms an image with charged particles and generates an electric field to transfer the image onto a medium 500. The transfer unit 100 includes a developing device 110, a primary transfer roll 120, and an intermediate transfer belt 131. The intermediate transfer belt 131 is stretched by rollers 132, 133 and a backup roll 140 between the developing device 110 and a position where transfer onto the medium 500 is performed. The transfer unit 100 also includes a cleaning device 150 for removing particles adhering to the intermediate transfer belt 131.

[0015] The developing device 110 is a unit that forms an electrostatic latent image of a transfer target image on a photoconductor, and causes charged particles to adhere to the electrostatic latent image on the photoconductor to develop the image. As the developing device 110, an existing device used in an electrophotographic image forming apparatus can be used. FIG. 2 shows a configuration example in a case where color image forming processing is performed with four colors obtained by adding black to three colors of yellow, magenta, and cyan. The developing device 110 is provided for each of these colors, and in FIG. 2, the developing devices 110 for the respective colors of yellow, magenta, cyan, and black are described with suffixes Y, M, C, and K indicating the corresponding colors. In the following description, when distinguishing each color with respect to the developing device 110, suffixes Y, M, C, and K are added to reference numerals, but when there is no need to distinguish each color, the description is given without adding suffixes.

[0016] The primary transfer roll 120 is a unit used to transfer (primary transfer) the image formed in the developing unit 110 to the intermediate transfer belt 131. The primary transfer roll 120 is positioned opposite the photoreceptor of the developing unit 110, and the intermediate transfer belt 131 is positioned between the developing unit 110 and the primary transfer roll 120. The primary transfer roll 120 is provided in correspondence to each of the developing units 110Y, 110M, 110C, and 110K. In Figure 2, each primary transfer roll 120 corresponding to the developing unit 110Y, 110M, 110C, and 110K for each color is indicated with the subscripts Y, M, C, and K to indicate the corresponding color. In the following description, when distinguishing each color with respect to the primary transfer roll 120, the subscripts Y, M, C, and K are added to the symbols, but when it is not necessary to distinguish each color, the subscripts are omitted.

[0017] The intermediate transfer belt 131, rollers 132 and 133, and backup roll 140 are units used to transfer the image formed in the developing apparatus 110 to the medium 500. As shown in Figure 2, the intermediate transfer belt 131 is stretched over the rollers 132 and 133 and the backup roll 140 and rotates in the direction of the arrow in Figure 2 (counterclockwise in the illustrated example). The rotation of the intermediate transfer belt 131 is achieved, for example, by using a roller that rotates one or both of the rollers 132 and 133, and pulling the intermediate transfer belt 131 with the rotation of this roller.

[0018] In the configuration example shown in Figure 2, the outer surface of the intermediate transfer belt 131 is the surface that holds the image (hereinafter referred to as the "transfer surface"). As the intermediate transfer belt 131 passes between the developing device 110 and the primary transfer roll 120, the image is transferred from the photoreceptor of the developing device 110 to the transfer surface of the intermediate transfer belt 131. In the configuration example shown in Figure 2, a multicolor image is formed by superimposing images of yellow (Y), magenta (M), cyan (C), and black (K) onto the transfer surface using the developing devices 110Y, 110M, 110C, 110K and the primary transfer rolls 120Y, 120M, 120C, 120K.

[0019] The backup roll 140 brings the transfer surface of the intermediate transfer belt 131 into contact with the medium 500, transferring the image to the medium (secondary transfer). When transferring the image, a predetermined voltage is applied to the backup roll 140. This generates an electric field (hereinafter referred to as the "transfer electric field") in the area including the backup roll 140 and the medium 500, and the image formed by the charged particles is transferred from the intermediate transfer belt 131 to the medium 500. In this way, in order to transfer the image from the intermediate transfer belt 131 to the medium 500, current must flow from the backup roll 140 through the intermediate transfer belt 131 to the medium 500. If the medium 500 is a conductor such as a metal, current flows through the medium 500 itself, generating a transfer electric field and transferring the image to the surface of the medium 500. On the other hand, if the medium 500 is not a conductor, current does not flow through the medium, and therefore the image cannot be transferred as is. Therefore, when a non-conductor material is used as the medium 500, measures are taken beforehand to allow current to flow through the medium 500, such as forming a layer of conductive material (hereinafter referred to as the "conductive layer") in at least the region on the surface of the medium 500 where the image is to be formed.

[0020] The procedure for transferring an image using the intermediate transfer belt 131 will now be described. As the intermediate transfer belt 131 rotates, the developing devices 110Y, 110M, 110C, 110K and the primary transfer rolls 120Y, 120M, 120C, 120K sequentially superimpose images of yellow (Y), magenta (M), cyan (C), and black (K) onto the transfer surface of the intermediate transfer belt 131 (the outer surface in Figure 2), forming a multicolor image. As the intermediate transfer belt 131 rotates further, the image formed on the transfer surface of the intermediate transfer belt 131 reaches the position where the intermediate transfer belt 131 contacts the medium 500 (hereinafter referred to as the "transfer position"). At this point, as described above, a voltage is applied to the backup roll 140 to generate a transfer electric field, and the image is transferred from the intermediate transfer belt 131 to the medium 500.

[0021] The cleaning device 150 is a unit that removes particles adhering to the transfer surface of the intermediate transfer belt 131. The cleaning device 150 is located downstream of the transfer position in the rotational direction of the intermediate transfer belt 131 and upstream of the developing device 110Y and the primary transfer roll 120Y. As a result, after the image is transferred from the intermediate transfer belt 131 to the medium 500, any particles remaining on the transfer surface of the intermediate transfer belt 131 are removed by the cleaning device 150. Then, in the next operation cycle, a new image is transferred (primary transfer) to the transfer surface from which the particles have been removed.

[0022] <Configuration of the transport mechanism 400 and mounting structure of the media 500> Here, the mounting structure for the medium 500 will be described. In this embodiment, we assume that the medium 500 has various thicknesses and shapes. When the medium 500 is directly placed on a transport path composed of belts and rollers and transported, if the thickness and shape of the medium 500 differ, the height of the medium 500 relative to the transport path will differ at the transfer position of the transfer section 100, making it difficult to properly bring the intermediate transfer belt 131 into contact with the medium 500. Specifically, if the height of the medium 500 is low, the medium 500 will not contact the intermediate transfer belt 131, and if the height of the medium 500 is high, a strong impact may occur when the medium 500 contacts the intermediate transfer belt 131. Therefore, in this embodiment, the transport mechanism 400 places the medium 500 on a mounting base 420 equipped with height control means, and transports the medium 500 together with this mounting base 420.

[0023] Referring to Figure 2, the transport mechanism 400 includes a transport rail 410 that specifies the transport path for the medium 500, and a mounting base 420 that moves along the transport rail 410. The mounting base 420 includes legs 421 attached to the transport rail 410 and a base 422 for placing the medium 500 on. A jig 423 for holding the medium 500 on the base 422 is attached to the base 422. The transport mechanism 400 is an example of a transport unit.

[0024] In the configuration example shown in Figure 1, the transport rail 410 is installed from the media attachment / detachment section 300 through the fixing section 200 to the transfer section 100. The end of the transport rail 410 on the media attachment / detachment section 300 side is the transport start position and the transport end position. The mounting base 420 is transported from the transport start position of the media attachment / detachment section 300 to the left in Figure 1, and the image is transferred to the media 500 in the transfer section 100. After the image transfer, the mounting base 420 is transported to the right in Figure 1, and after the image is fixed to the media 500 in the fixing section 200, it reaches the transport end position of the media attachment / detachment section 300.

[0025] The leg portion 421 is attached to the transport rail 410 and moves along the transport rail 410. The mechanism for the leg portion 421 to move along the transport rail 410 is not particularly limited. For example, the leg portion 421 may be equipped with a drive device to allow it to move on its own, or the transport rail 410 may be equipped with a means for pulling the leg portion 421. The leg portion 421 also has a height control means for controlling the height of the base portion 422. The leg portion 421 is an example of a height adjustment unit. The configuration of the height control means is not particularly limited. For example, it may be configured to raise and lower the base portion 422 using a rack and pinion and a drive motor. Alternatively, it may be configured to control the height of the base portion 422 by manually operating a gear that is linked to the height of the base portion 422. Furthermore, various methods can be used for operating the height control. For example, an input interface to the control unit of the drive motor may be provided, and the operator of the image forming apparatus 10 may manually input and set the height data using the input interface. Alternatively, a sensor may be used to automatically detect the height of the medium 500 mounted on the mounting base 420, and the drive motor may be controlled so that the medium 500 is at an appropriate height.

[0026] The base portion 422 is attached to the leg portion 421 and is a platform on which the medium 500 is placed via the jig 423. The base portion 422 is provided with fasteners (not shown) for positioning the jig 423. Any jig 423 that fits these fasteners can be positioned and attached to the base portion 422 regardless of the shape of the jig 423 itself.

[0027] Furthermore, the base portion 422 is mounted so as to rise and fall relative to the leg portion 421 in response to pressure from above. The rising and falling of the base portion 422 is achieved, for example, by interposing an elastic body at the joint between the base portion 422 and the leg portion 421. With this configuration, the impact when the medium 500 held by the jig 423 attached to the base portion 422 comes into contact with the intermediate transfer belt 131 of the transfer portion 100 is mitigated.

[0028] The jig 423 is a device that holds the medium 500 and is attached to the base portion 422. The part of the jig 423 that is attached to the base portion 422 has a shape and structure that fits the fasteners of the base portion 422. The jig 423 also has a shape for holding the medium 500. Therefore, by preparing a jig 423 according to the shape and size of the medium 500, various shapes and sizes of medium 500 can be placed on the mounting base 420.

[0029] <Pre-processing for image formation> The image forming apparatus 10 of this embodiment has a transport mechanism 400 configured as described above, and can therefore print on media 500 of various shapes and sizes. However, in order to prevent problems such as strong impacts occurring due to contact between the media 500 and the intermediate transfer belt 131 of the transfer unit 100, or failure to make contact, when transferring an image to the media 500, the height of the base unit 422 is controlled before the image transfer operation begins.

[0030] Figure 3 shows the operation of the transport mechanism 400 before image formation by the transfer unit 100 begins. Figure 3(A) shows the height control process, Figure 3(B) shows the mechanism retracted to the preparation position after height control, and Figure 3(C) shows the state when image transfer by the transfer unit 100 begins.

[0031] When image formation is performed on the medium 500, first, at the transport start position of the medium attachment / detachment unit 300, the medium 500 held by the jig 423 is set on the mounting base 420. Then, the height control means of the mounting base 420 lowers the medium 500 to a height where it does not come into contact with the intermediate transfer belt 131 of the transfer unit 100, and then the mounting base 420 with the medium 500 on it moves to below the transfer position of the transfer unit 100.

[0032] Next, the height of the mounting base 420 is controlled so that the medium 500 contacts the intermediate transfer belt 131 with an appropriate strength for transferring the image at the transfer position (arrow a in Figure 3(A)). Once the height control is performed, the information of the obtained appropriate height (hereinafter referred to as the "transfer execution height") is stored in the memory of the control unit. Then, the mounting base 420 is lowered to a height where the medium 500 does not contact the intermediate transfer belt 131 and moves to the preparation position for the transfer operation (arrow b in Figure 3(A)).

[0033] When the mounting base 420 moves to the preparation position, the height of the mounting base 420 is adjusted to the transfer execution height based on the information obtained from the height control. After this, the mounting base 420 moves to the transfer position (arrow c in Figure 3(B)), and when the medium 500 comes into contact with the intermediate transfer belt 131 at the transfer position, the transfer of the image begins (Figure 3(C)).

[0034] <Configuration of the fixing unit 200> Once the image is transferred to the medium 500 in the transfer unit 100, the image is then fixed in the fixing unit 200. In this embodiment, since images are formed on mediums 500 of various thicknesses and shapes, a non-contact fixing process is performed. The fixing unit 200 heats and melts the particles that form the image transferred to the medium 500 and fixes them to the surface of the medium 500.

[0035] Figure 4 shows the configuration and operation of the fixing unit 200. The fixing unit 200 includes an inlet 201, which is an opening for loading the medium 500, and an outlet 202, which is an opening for unloading the medium 500. In addition, the inlet 201 and outlet 202 of the fixing unit 200 in this embodiment are provided with opening and closing members, which are configured to open when loading and unloading the medium 500 and to close when performing the fixing process.

[0036] Here, the opening into which the medium 500 is brought in when the fixing process is performed by the fixing unit 200 is designated as the inlet 201, and the opening out on the side from which the medium 500 is discharged is designated as the outlet 202. In other words, the opening on the side facing the transfer unit 100 is designated as the inlet 201, and the opening on the side facing the medium attachment / detachment unit 300 is designated as the outlet 202. In the example shown in Figure 4, the opening on the left is the inlet 201, and the opening on the right is the outlet 202. In this embodiment of the image forming apparatus 10, when the medium 500 is transported from the transport start position of the medium attachment / detachment unit 300 to the transfer unit 100, the medium 500 passes through the fixing unit 200. At this time, the medium 500 enters the fixing unit 200 from the outlet 202 and exits from the inlet 201, the opposite of when the fixing process is performed. However, in this embodiment, the inlet 201 and outlet 202 were set as described above based on the operation when the fixing process is performed in the fixing unit 200.

[0037] The fixing unit 200 is equipped with a heat source 210 for heat fixing. Various existing heat sources such as halogen lamps, ceramic heaters, and infrared lamps can be used as the heat source 210. Alternatively, instead of the heat source 210, a device that heats the particles forming the image by irradiating them with an infrared laser may be used. The fixing unit 200 in this embodiment is provided with a covering member that can cover the heat source 210, and is configured to expose the heat source 210 when performing the fixing process.

[0038] In the example shown in Figure 4, retractable shutters 220 and 230 are provided at the entrance 201 and exit 202. Shutter 220 is an example of an entrance opening / closing member, and shutter 230 is an example of an exit opening / closing member. The shutters 220 and 230 are provided above the entrance 201 and exit 202, and when rolled up, they rise from the lower ends of the entrance 201 and exit 202, opening the entrance 201 and exit 202. In addition, a retractable shutter 240 is provided inside the fixing section 200 as a covering member to cover the heat source 210. Shutter 240 is an example of a covering member for the heat source 210. The material of the shutters 220, 230 and 240 is not particularly limited as long as it can withstand the temperature inside the fixing section 200 and has a certain level of heat insulation effect. In this embodiment, the operation of the shutters 220, 230 and 240 is operated individually according to timings such as when the medium 500 is brought in or taken out. This suppresses the decrease in internal temperature of the fixing section 200 caused by opening the loading entrance 201 and the loading exit 202.

[0039] Figure 5 illustrates the operation of the shutters 220, 230, and 240 of the fixing unit 200. Figure 5(A) shows the state when the medium 500 is being loaded, Figure 5(B) shows the state when the fixing process is being executed, and Figure 5(C) shows the state when the medium 500 is being unloaded. When the medium 500 on which the image has been transferred by the transfer unit 100 is loaded into the fixing unit 200, as shown in Figure 5(A), only the shutter 220 of the loading entrance 201 opens, and the shutter 230 of the unloading entrance 202 closes. This suppresses the decrease in temperature inside the fixing unit 200 compared to a configuration without opening / closing members at the opening. In addition, by keeping the shutter 240 closed at this time, the decrease in temperature of the heat source 210 due to the decrease in temperature inside the fixing unit 200 caused by the opening of the shutter 220 is suppressed.

[0040] During the fixing process, as shown in Figure 5(B), the shutter 220 at the entrance 201 and the shutter 230 at the exit 202 close, and the shutter 240 opens. This causes the temperature inside the fixing unit 200 to rise, heating the medium 500 and fixing the image. When the medium 500 that has been fixed is to be removed from the fixing unit 200, as shown in Figure 5(C), only the shutter 230 at the exit 202 opens, and the shutter 220 at the entrance 201 closes. This suppresses the decrease in temperature inside the fixing unit 200 compared to a configuration without opening / closing members at the opening. In addition, by keeping the shutter 240 closed at this time, the decrease in the temperature of the heat source 210 that occurs due to the decrease in temperature inside the fixing unit 200 caused by the opening of the shutter 230 is suppressed.

[0041] The loading entrance 201 and shutter 220 will be described further. In this embodiment, an upper limit is set on the height of the loading entrance 201. To explain the height limitation of the loading entrance 201, refer again to Figure 1. In Figure 1, the transfer unit 100, the fixing unit 200, and the media loading / unloading unit 300 of the image forming apparatus 10 are each depicted as blocks. However, this is a representation of the units separated by function and does not mean that in the actual image forming apparatus 10, the transfer unit 100, the fixing unit 200, and the media loading / unloading unit 300 each have separate housings. In reality, the transfer unit 100 and the fixing unit 200 may be adjacent to each other within a single housing.

[0042] When the loading port 201 of the fixing unit 200 is opened, heat leaks out from inside the fixing unit 200. In such a case, if the transfer unit 100 and the fixing unit 200 are adjacent to each other, the image formed on the developing device 110 and the intermediate transfer belt 131 of the transfer unit 100 may be affected by the heat leaked from the fixing unit 200. In this embodiment, the influence of heat leaked from the fixing unit 200 on the transfer unit 100 is suppressed by limiting the height of the loading port 201 of the fixing unit 200.

[0043] Figure 6 shows the height restriction at the loading entrance 201 of the fixing unit 200. In the example shown in Figure 6, when the shutter 220 of the loading entrance 201 is rolled up to its highest position, the lower end of the shutter 220 is at the same height as the transfer position of the transfer unit 100. In this way, by configuring the loading entrance 201 so that its height is below the height of the transfer position when it is in its most open state, the transfer of heat from inside the fixing unit 200 to the intermediate transfer belt 131 of the transfer unit 100 is suppressed. Note that although Figure 6 shows the height of the lower end of the shutter 220 when it is rolled up to its highest position, the manner in which the height of the loading entrance 201 is restricted is not limited to the manner shown in Figure 6. For example, the opening and closing operation of the shutter 220 may be controlled so that the upper limit of the shutter 220 when it is rolled up does not exceed the height of the transfer position of the transfer unit 100, regardless of the height of the installation position of the shutter 220. Alternatively, the height of the loading entrance 201 itself may be set to be below the height of the transfer position of the transfer unit 100.

[0044] In the examples shown in Figures 4 and 5, shutters 220, 230, and 240 were used as opening and closing members for the entrance 201 and exit 202, and as covering members for the heat source 210. However, these opening and closing members and covering members are not limited to the above configuration, as long as they suppress the decrease in temperature inside the fixing unit 200 and the heat source 210. For example, an opening and closing door may be provided instead of the shutters 220, 230, and 240. In particular, at the exit 202, an opening and closing member may not be provided, and the movement of air between the inside and outside of the fixing unit 200 may be blocked by a curtain or air curtain made of insulating material. Since the medium 500 passes through the exit 202 after the fixing process is completed, the image formed on the medium 500 will not be affected by contact with the curtain or the air pressure of the air curtain.

[0045] Figure 7 shows an example in which an air curtain is used as a means of opening and closing the outlet 202. In the fixing section 200 shown in Figure 7, the heat source 210, shutters 220 and 240 are the same as those shown in Figure 4. Unlike the shutter 230 shown in Figure 4, the fixing section 200 shown in Figure 7 has an air curtain outlet 250 at the outlet 202. In the configuration shown in Figure 7, the outlet 250 is located at the top of the outlet 202 and blows air downwards. This airflow blocks the movement of air between the inside and outside of the fixing section 200, suppressing heat leakage from inside the fixing section 200.

[0046] Although embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the above embodiments. For example, in the above embodiments, the shutter 240 covering the heat source 210 is closed when the medium 500 is loaded into the fixing unit 200 (see Figure 5(A)). In contrast, the shutter 240 may be left open when the medium 500 is loaded. In this way, the state in which the heat source 210 is exposed is maintained, so even if the opening and closing means of the discharge port 202 is opened, the decrease in the temperature inside the fixing unit 200 is suppressed. In addition, various modifications and substitutions of configurations that do not depart from the technical concept of the present invention are included in the present invention.

[0047] <Note> (((1))) An image forming apparatus comprising: a transport unit for transporting an object along a transport path; a transfer unit for transferring an image onto the object along the transport path; and a fixing unit having a heat source for raising the internal temperature, which transports the object onto which the image has been transferred according to the transport path, and which is provided with a loading opening / closing member that opens the loading opening when the object is loaded and closes when the object is loaded. (((2))) The image forming apparatus according to (((1))), characterized in that when the loading port of the fixing unit is in its most open state, the height of the loading port is approximately the same as the height of the position where the transfer unit transfers an image onto the object. (((3))) The image forming apparatus according to (((1))) or (((2))), characterized in that the loading opening / closing member of the fixing unit is a shutter that opens the loading opening by rising from the lower end of the loading opening, and the upper limit of the rise of the shutter is approximately the same height as the height of the position in which the transfer unit transfers an image onto the object. (((4))) The fixing unit is characterized by comprising an outlet opening / closing member that opens an outlet from which the object is discharged after the fixing process of the image transferred to the object has been performed, and closes when the object has been discharged, as described in any of (((1))) to (((3))). (((5))) The image forming apparatus according to (((4))), wherein the fixing portion further comprises a covering portion that covers the heat source when the outlet opening / closing member opens the outlet, and exposes the heat source when the outlet opening / closing member closes the outlet.

[0048] According to the image forming apparatus described in (((1))), compared to a configuration in which an object is loaded through an opening without an opening / closing mechanism, it is possible to suppress the decrease in temperature inside the fixing section when an object is loaded. According to the image forming apparatus described in (((2))), the temperature drop inside the fixing section when the opening is made can be suppressed compared to a configuration in which the height of the loading entrance is not restricted. According to the image forming apparatus described in (((3))), the temperature drop inside the fixing section when the shutter is open can be suppressed compared to a configuration in which the raised position of the shutter is not restricted. According to the image forming apparatus described in (((4))), compared to a configuration in which an object is unloaded from an opening without an opening / closing mechanism, it is possible to suppress the decrease in temperature inside the fixing section when an object is unloaded. According to the image forming apparatus described in (((5))), the decrease in temperature inside the fixing section when the object is unloaded can be further suppressed compared to a configuration in which the heat source is exposed regardless of whether the outlet is open or closed. [Explanation of Symbols]

[0049] 10…Image forming apparatus, 100…Transfer section, 110…Developing apparatus, 120…Primary transfer roll, 131…Intermediate transfer belt, 132, 133…Rollers, 140…Backup roll, 150…Cleaning apparatus, 200…Fixing section, 201…Inlet, 202…Outlet, 210…Heat source, 220, 230, 240…Shutter, 250…Air outlet, 300…Media loading / unloading section, 400…Conveying mechanism, 410…Conveying rail, 420…Mounting base, 421…Legs, 422…Base, 423…Jig, 500…Media

Claims

1. A transport unit that transports the object along the transport route, A transfer unit that transfers an image to an object along the aforementioned transport path, The device comprises a fixing unit having a heat source that raises the internal temperature, the object onto which the image has been transferred is transported along the transport path, and a loading door opening / closing member that opens the loading door when the object is transported and closes when the object is transported, The fixing unit includes an outlet opening / closing member that opens an outlet from which the object is discharged after the fixing process of the image transferred to the object has been performed, and closes the outlet when the object has been discharged. An image forming apparatus characterized in that the outlet opening / closing member includes a covering portion that covers the heat source when the outlet is opened, and exposes the heat source when the outlet opening / closing member closes the outlet.

2. The image forming apparatus according to claim 1, characterized in that when the loading port of the fixing unit is in its most open state, the height of the loading port is approximately the same as the height of the position where the transfer unit transfers an image onto the object.

3. The image forming apparatus according to claim 2, wherein the loading opening / closing member of the fixing unit is a shutter that opens the loading opening by rising from the lower end of the loading opening, and the upper limit of the rise of the shutter is approximately the same height as the height of the position in which the transfer unit transfers an image onto the object.

Images