Image forming device

Abstract

To provide an image forming device which prohibits an operation in the case where option devices larger in number than a threshold value are connected.SOLUTION: An image forming device 100 includes a connection unit 100a and a determination unit 300. A plurality of first option devices can be laminated and connected to the image forming device, and a second option device is installed on a floor surface 180 and can be connected to the connection unit of the image forming device or to the first option device. In the case where the second option device is not connected to the image forming device (NO in S201), and the number E of the first option devices connected to the image forming device is larger than a first threshold value N, the determination unit prohibits the operation of the image forming device (S203), and in the case where the second option device is connected to the image forming device (YES in S201), and the number E of the first option devices connected to the image forming device is larger than a second threshold value M, the determination unit prohibits the operation of the image forming device (S206).SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus to which an optional device can be connected. [Background technology]

[0002] Conventionally, there is an image forming apparatus that is configured such that multiple optional cassettes for feeding sheets can be stacked and attached below the main body, and that sheets are transported from the optional cassettes to an image forming unit through a sheet transport path in the optional cassette and a sheet transport path in the main body. For example, the image forming apparatus disclosed in Patent Document 1 is configured such that an optional cassette can be added below the main body. By adding an optional cassette, a large amount of sheets can be fed, and different types of sheets can be selected and used. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-230774 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when a user purchases optional cassettes separately and connects them to an image forming apparatus, a number of optional cassettes exceeding the expected number may be connected to the image forming apparatus. An image forming apparatus to which a large number of optional cassettes are connected may be used without problems under normal conditions, but it is necessary to prevent the image forming apparatus from falling over when a user leans on the image forming apparatus or when the floor surface vibrates significantly due to an earthquake or the like.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide an image forming apparatus that is prohibited from operating when a number of optional devices connected is greater than a threshold value. [Means for solving the problem]

[0006] An image forming apparatus for forming an image on a sheet according to an embodiment of the present invention comprises: a connection section to which the first optional device and the second optional device are selectively and detachably connected; a determination unit that determines whether or not to prohibit operation of the image forming apparatus when the image forming apparatus is started up; Equipped with the first option device is connectable to the connection unit of the image forming device, the first optional device is connectable to another first optional device, thereby allowing a plurality of first optional devices to be stacked and connected to the image forming apparatus; the second optional device is installed on a floor surface and is connectable to the connection unit of the image forming apparatus or the first optional device; the determination unit prohibits the operation of the image forming apparatus when the second optional device is not connected to the image forming apparatus and the number of the first optional devices connected to the image forming apparatus is greater than a first threshold value; The judgment unit is characterized in that it prohibits the operation of the image forming device when the second optional device is connected to the image forming device and the number of the first optional devices connected to the image forming device is greater than a second threshold value. According to another embodiment of the present invention, an image forming apparatus includes: an image forming unit that forms an image on a sheet; a connection section to which an optional device including a sheet storage section for storing sheets on which an image is formed by the image forming section is detachably connected; a determination unit that determines whether or not to prohibit an operation of the image forming apparatus; Equipped with the optional device is connectable to another optional device, whereby a plurality of optional devices can be stacked and connected to the image forming device; when a predetermined number of optional devices are connected to the image forming apparatus and all of the predetermined number of optional devices connected to the image forming apparatus are first optional devices, the determination unit determines to prohibit operation of the image forming apparatus; When the predetermined number of optional devices are connected to the image forming device and the predetermined number of optional devices connected to the image forming device include the first optional device and a second optional device that is different from the first optional device and is installed on the floor, the judgment unit does not prohibit operation of the image forming device. Effect of the Invention

[0007] According to the present invention, it is possible to provide an image forming apparatus that is prohibited from operating when a number of optional devices greater than a threshold value is connected. [Brief description of the drawings]

[0008] [Figure 1] FIG. [Diagram 2] FIG. 2 is a block diagram of a control unit of the image forming apparatus. [Diagram 3] FIG. 2 is a cross-sectional view of an option cassette that can be connected to the image forming apparatus. [Figure 4] FIG. 4 is a diagram showing a screen displayed on the operation unit. [Diagram 5] 4 is a flowchart showing an image forming operation of the image forming apparatus. [Figure 6] 1 is a flow diagram illustrating configuration determination. [Figure 7] FIG. 1 is a diagram showing a first example of the arrangement of an image forming apparatus. [Figure 8] FIG. 13 is a diagram showing a second example of the configuration of an image forming apparatus. [Figure 9] FIG. 13 is a diagram showing a third example of the configuration of an image forming apparatus. [Figure 10] Cross-sectional view of the optional cassette with casters. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (Image forming device) FIG. 1 is a cross-sectional view of an image forming apparatus 100. The image forming apparatus 100 of this embodiment is a digital copier that forms an image on a recording medium (hereinafter referred to as a sheet) using an electrophotographic image forming process. However, the image forming apparatus 100 is not limited to this, and may be an electrophotographic printer (e.g., a color laser beam printer, a color LED printer, etc.), an MFP (multi-function peripheral), a facsimile machine, or a printing machine. The image forming apparatus 100 forms a color image, but may also form a monochrome image. The image forming apparatus 100 includes an original feeder 101, an image reader unit 102, and a printer unit 103.

[0010] The document feeder 101 transports documents one by one from the top page of a stack of documents set on a document tray 200 via a curved path 201 to a platen glass 202, transports the documents from left to right on the platen glass 202, and discharges the documents onto a discharge tray 203. At this time, a reader scanner unit 204 is held at a predetermined position. As the documents pass over the reader scanner unit 204 from left to right, the reader scanner unit 204 reads the documents.

[0011] When an original passes over the reader scanner unit 204, light is irradiated onto the original from a light source 205 of the reader scanner unit 204, and the light reflected from the original is imaged on an image sensor 209 via mirrors 206 and 207 and an imaging lens 208. The image sensor 209 converts the light reflected from the original into image data.

[0012] Alternatively, the user may open the document feeder 101, place the document on the platen glass 202, and close the document feeder 101. The document placed on the platen glass 202 can be read by the image sensor 209 while the reader scanner unit 204 moves from left to right. The image reader unit 102 performs image processing on the image data of the read document and transmits a color separation image signal to the printer unit 103.

[0013] The printer unit 103 has a first image forming unit UY, a second image forming unit UM, a third image forming unit UC, and a fourth image forming unit UK arranged in tandem. The first image forming unit UY, the second image forming unit UM, the third image forming unit UC, and the fourth image forming unit UK form toner images on the respective photosensitive drums 108y, 108m, 108c, and 108k using a laser exposure type electrophotographic process.

[0014] Based on the color separation image signals transmitted from the image sensor 209 to the printer unit 103, the first image forming unit UY forms a yellow toner image on the surface of the photosensitive drum 108y. Similarly, the second image forming unit UM forms a magenta toner image on the surface of the photosensitive drum 108m. The third image forming unit UC forms a cyan toner image on the surface of the photosensitive drum 108c. The fourth image forming unit UK forms a black toner image on the surface of the photosensitive drum 108k.

[0015] The yellow, magenta, cyan and black toner images formed on the surfaces of the photosensitive drums 108y, 108m, 108c and 108k are sequentially transferred to the intermediate transfer belt 104 at primary transfer units 105y, 105m, 105c and 105k, respectively. The four toner images are superimposed to form an unfixed full-color toner image on the intermediate transfer belt 104.

[0016] Meanwhile, a sheet is fed from the cassette feeding mechanism 190 or the manual feeding unit 111 to the secondary transfer unit 106 at a predetermined control timing. A sheet cassette (hereinafter referred to as a first optional cassette) 191 (FIG. 3(a)) or a sheet cassette (hereinafter referred to as a second optional cassette) 192 (FIG. 3(b)) described later can be connected as an option to the image forming apparatus 100. A connection unit 100a to which the first optional cassette 191 and the second optional cassette 192 are selectively and detachably connected is provided at the bottom of the image forming apparatus 100. When the first optional cassette 191 or the second optional cassette 192 is connected to the image forming apparatus 100, a sheet is fed from the first optional cassette 191 or the second optional cassette 192 to the secondary transfer unit 106 at a predetermined control timing. In the secondary transfer unit 106, a full-color toner image on the intermediate transfer belt 104 is transferred to the sheet.

[0017] The sheet is separated from the intermediate transfer belt 104 and conveyed to the fixing unit 107. In the fixing unit 107, the sheet is sandwiched between a pair of fixing rollers 109 and conveyed. The unfixed full-color toner image is heated and pressurized by the pair of fixing rollers 109, melted and mixed, and fixed as a full-color permanently fixed image on the surface of the sheet. The sheet that has left the fixing unit 107 is once guided to a path 122 by an inverting flapper 121. After the rear end of the sheet passes through the inverting flapper 121, the sheet is switched back and guided by the inverting flapper 121 to the discharge rollers 118. As a result, the sheet is discharged from the image forming apparatus 100 by the discharge rollers 118 with the surface on which the image has been formed facing downward (face down).

[0018] When double-sided printing is performed, the sheet that has passed through the fixing unit 107 is guided to a path 122 by a reversing flapper 121. After the trailing end of the sheet passes through a double-sided flapper 123, the sheet is switched back and guided to a double-sided conveying path 112 by the double-sided flapper 123. As a result, the sheet is conveyed to the secondary transfer unit 106, and an image is formed on the back side (second side) of the sheet.

[0019] (Control unit) FIG. 2 is a block diagram of the control unit 400 of the image forming apparatus 100. The control unit 400 has a CPU 300, a ROM 301, a RAM 302, and a feed stage detection unit 305. The CPU 300 is electrically connected to the image reader unit 102, the printer unit 103, and an operation unit 304. The operation unit 304 is provided in the image forming apparatus 100. The CPU 300 performs all control of the image forming apparatus 100. The ROM 301 is a storage unit that stores a control program to be executed by the CPU 300. The RAM 302 is a storage unit that is used as a work area required for the CPU 300 to control the image forming apparatus 100. The RAM 302 stores image data (digital image data) obtained by the image reader unit 102 reading an original and information obtained from the feed stage detection unit 305. The RAM 302 is also used as a work area for the CPU 300 to perform image processing on the image data obtained from the image reader unit 102.

[0020] The operation unit 304 is used to set a copy job that the user wants to execute on the image forming apparatus 100 and to display messages to the user. In accordance with the settings from the operation unit 304, the CPU 300 conveys the document set in the document tray 200 to the image reader unit 102, reads the image of the document to generate image data, and stores the image data in the RAM 302. In accordance with the copy job settings from the operation unit 304, such as the setting of single-sided printing / double-sided printing, the CPU 300 performs necessary image processing on the image data from the image reader unit 102, and stores in the RAM 302 the image data for the image to be formed on a sheet.

[0021] (Optional cassette) FIG. 3 is a cross-sectional view of an optional cassette (191, 192) connectable to the image forming apparatus 100. FIG. 3(a) is a cross-sectional view of a first optional cassette 191. The first optional cassette (first optional device) 191 is a feeding cassette having a sheet storage section 191a for storing sheets and a feeding section 191b for feeding sheets one by one from the sheet storage section 191a. The first optional cassette 191 can be connected to the image forming apparatus 100 from below in the vertical direction. An electrical contact 91a is provided on the upper part of the first optional cassette 191. The first optional cassette 191 can be connected to the bottom of the image forming apparatus 100. When the first optional cassette 191 is connected to the bottom of the image forming apparatus 100, the electrical contact 91a of the first optional cassette 191 is connected to an electrical contact 90 (FIG. 1) provided on the bottom of the image forming apparatus 100. Thereby, the feeding stage detection unit 305 detects that the first optional cassette 191 is connected to the image forming apparatus 100. In other words, when the first optional cassette 191 is connected to the image forming apparatus 100, the feeding stage detection unit 305 detects that the first optional cassette 191 is connected to the image forming apparatus 100.

[0022] An electrical contact 91b is provided at the bottom of the first option cassette 191. The first option cassette 191 can be connected to another first option cassette 191. A plurality of first option cassettes 191 as a plurality of first option devices can be stacked and connected to the image forming apparatus 100. When the first option cassette 191 and another first option cassette 191 are connected, the electrical contact 91b of the first option cassette 191 is connected to the electrical contact 91a of the other first option cassette 191. In this way, when a plurality of first option cassettes 191 are connected and stacked, the feeding stage detection unit 305 can obtain connection information about the plurality of first option cassettes 191 connected to the image forming apparatus 100. That is, for example, when two first option cassettes 191 are stacked and connected to the image forming apparatus 100, the feeding stage detection unit 305 detects that the two first option cassettes 191 are connected to the image forming apparatus 100. In this manner, the feeding stage detection unit 305 can detect the number E of the first optional cassettes 191 connected to the image forming apparatus 100. The number E of the first optional cassettes 191 connected to the image forming apparatus 100 is stored in the RAM 302 as feeding stage information.

[0023] FIG. 3B is a cross-sectional view of the second option cassette 192. The second option cassette (second option device) 192 is a feeding cassette having a sheet storage section 192a for storing sheets and a feeding section 192b for feeding sheets one by one from the sheet storage section 192a. The second option cassette 192 can be connected to the image forming apparatus 100 from below in the vertical direction. An electrical contact 92 is provided on the upper part of the second option cassette 192. The second option cassette 192 can be connected to the bottom of the image forming apparatus 100 or the bottom of the first option cassette 191. A bottom plate 193 having a larger installation floor area than the bottom of the first option cassette 191 is provided on the bottom of the second option cassette 192. The bottom plate 193 makes the second option cassette 192 less likely to tip over than the first option cassette 191. Neither the first option cassette 191 nor another second option cassette 192 can be connected to the bottom of the bottom plate 193 of the second option cassette 192. The second option cassette 192 is connected to the lowest level and is placed on the floor.

[0024] When the second option cassette 192 is connected to the bottom of the image forming apparatus 100, the electrical contact 92 of the second option cassette 192 is connected to the electrical contact 90 (FIG. 1) of the image forming apparatus 100. As a result, the feeding stage detection unit 305 detects that the second option cassette 192 is connected to the image forming apparatus 100. Information on whether the second option cassette 192 is connected to the image forming apparatus 100 is stored in the RAM 302 as feeding stage information. When the second option cassette 192 is connected to the bottom of the first option cassette 191 connected to the bottom of the image forming apparatus 100, the electrical contact 92 of the second option cassette 192 is connected to the electrical contact 91b of the first option cassette 191. As a result, the feeding stage detection unit 305 detects that the second option cassette 192 is connected to the bottom of the first option cassette 191 connected to the bottom of the image forming apparatus 100.

[0025] (Operation unit) FIG. 4 is a diagram showing a screen displayed on the operation unit 304. The operation unit 304 is configured with a touch panel. FIG. 4(A) is a diagram showing an operation screen 310 displayed on the touch panel of the operation unit 304. Soft keys are created on the operation screen 310. On the operation screen 310, soft keys for setting image forming operations such as magnification change, paper selection, single-sided / double-sided printing instruction, color mode / monochrome mode designation, image density, and finishing are displayed. Furthermore, on the operation screen 310, a start key for causing the image forming apparatus 100 to start the image forming operation is displayed. When the user touches the start key, the image forming apparatus 100 starts the image forming operation.

[0026] 4(B) is a diagram showing a message screen 311 displayed on the touch panel of the operation unit 304. For example, messages such as "Please check the device configuration," "An unrecommended device configuration has been detected," and "Please check the feeding cassette configuration" are displayed on the message screen 311. When the message screen 311 shown in FIG. 4(B) is displayed on the entire touch panel of the operation unit 304, the soft keys and start key for setting the image forming operation are not displayed, so that the user cannot set or start the image forming operation of the image forming apparatus 100.

[0027] (Image formation operation) The image forming operation of the image forming apparatus 100 will be described with reference to Fig. 5. Fig. 5 is a flow chart showing the image forming operation of the image forming apparatus 100. When the power supply of the image forming apparatus 100 is turned on, the CPU 300 executes the image forming operation shown in Fig. 5 based on the program stored in the ROM 301.

[0028] CPU 300 acquires feeding stage information stored in RAM 302 (S101). The feeding stage information includes information detected by feeding stage detection unit 305 as to whether or not second option cassette 192 is connected to image forming apparatus 100, and information on the number E of first option cassettes 191 connected to image forming apparatus 100. CPU 300 as a determination unit executes configuration determination based on the feeding stage information at the time of startup of image forming apparatus 100 to determine whether or not to permit operation of image forming apparatus 100 (S102). The configuration determination of S102 will be described later.

[0029] CPU 300 judges whether or not the operation of image forming apparatus 100 is permitted based on the result of the configuration judgment in S102 (S103). If the operation is permitted (YES in S103), CPU 300 displays operation screen 310 as shown in FIG. 4A on operation unit 304 (S104). CPU 300 judges whether or not a job has been input (S105). If a job has not been input (NO in S105), CPU 300 waits for a job to be input (S105). If a job has been input (YES in S105), CPU 300 executes an image forming operation (S106). After the image forming operation is executed, CPU 300 returns the process to S105.

[0030] If the operation of the image forming apparatus 100 is not permitted (NO in S103), the CPU 300 displays a message screen 311 as shown in FIG. 4B on the operation unit 304 (S107). When the message screen 311 is displayed on the operation unit 304, the operation of the image forming apparatus 100 is prohibited. In this case, the state of the image forming apparatus 100 cannot be changed except for turning off the power of the image forming apparatus 100. The CPU 300 judges whether the power of the image forming apparatus 100 has been turned off (S108). If the power has not been turned off (NO in S108), the CPU 300 waits for the power to be turned off (S108). If the power has been turned off (YES in S108), the CPU 300 ends the image forming operation. After that, when the power is turned on, the CPU 300 starts the image forming operation and executes the process from S101.

[0031] (Configuration judgment) Next, the configuration determination in S102 will be described with reference to Fig. 6. Fig. 6 is a flow chart showing the configuration determination. In the following description, the first set number (first threshold) N is the number of first option cassettes 191 (allowable connection number) that are allowed to be connected to the image forming apparatus 100 when the second option cassette 192 is not connected to the image forming apparatus 100. The second set number (second threshold) M is the number of first option cassettes 191 (allowable connection number) that are allowed to be connected to the image forming apparatus 100 when the second option cassette 192 is connected to the image forming apparatus 100.

[0032] When the configuration determination is started, the CPU 300 judges whether or not the second option cassette 192 is connected to the image forming apparatus 100 (S201). If the second option cassette 192 is not connected to the image forming apparatus 100 (NO in S201), the CPU 300 advances the process to S202. The CPU 300 judges whether or not the number E of the first option cassettes 191 connected to the image forming apparatus 100 is greater than the first set number N (S202), if the number E of the first option cassettes 191 connected to the image forming apparatus 100 is greater than the first set number N (YES in S202), the CPU 300 does not permit the operation of the image forming apparatus 100 (S203). On the other hand, if the number E of the first option cassettes 191 connected to the image forming apparatus 100 is equal to or less than the first set number N (equal to or less than the first threshold) (NO in S202), the CPU 300 permits the operation of the image forming apparatus 100 (S204).

[0033] When the second option cassette 192 is connected to the image forming apparatus 100 (YES in S201), the CPU 300 advances the process to S205. The CPU 300 judges whether the number E of the first option cassettes 191 connected to the image forming apparatus 100 is greater than the second set number M (S205). When the number E of the first option cassettes 191 connected to the image forming apparatus 100 is greater than the second set number M (YES in S205), the CPU 300 does not permit the operation of the image forming apparatus 100 (S206). On the other hand, when the number E of the first option cassettes 191 connected to the image forming apparatus 100 is equal to or less than the second set number M (equal to or less than the second threshold) (NO in S205), the CPU 300 permits the operation of the image forming apparatus 100 (S207).

[0034] (Explanation of the first and second setting numbers) The first set number N and the second set number M will be described with reference to FIG. 7, FIG. 8, and FIG. 9. FIG. 7 is a diagram showing a first configuration example of the image forming apparatus 100. In the first configuration example, a second option cassette 192 and two first option cassettes 191 are connected to the image forming apparatus 100. The second option cassette 192 is installed on the floor surface 180. FIG. 8 is a diagram showing a second configuration example of the image forming apparatus 100. In the second configuration example, the second option cassette 192 is not connected to the image forming apparatus 100, and two first option cassettes 191 are connected to the image forming apparatus 100. The first option cassette 191 at the bottom is installed on the floor surface 180. FIG. 9 is a diagram showing a third configuration example of the image forming apparatus 100. In the third configuration example, the second option cassette 192 is not connected to the image forming apparatus 100, and three first option cassettes 191 are connected to the image forming apparatus 100. The first option cassette 191 at the bottom stage is placed on the floor surface 180 .

[0035] For example, a case where the first set number N is 1 and the second set number M is 1 (N=1, M=1) will be described. In the first configuration example shown in FIG. 7, since the second option cassette 192 is connected to the image forming apparatus 100 (YES in S201), the number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the second set number M (S205). Since E=2 and M=1, E>M (YES in S205), and the operation of the image forming apparatus 100 is not permitted (S206). In the second configuration example shown in FIG. 8, since the second option cassette 192 is not connected to the image forming apparatus 100 (NO in S201), the number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the first set number N (S202). Since E=2 and N=1, E>N (YES in S202), and the operation of the image forming apparatus 100 is not permitted (S203). In the third configuration example shown in Fig. 9, since the second option cassette 192 is not connected to the image forming apparatus 100 (NO in S201), the number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the first set number N (S202). Since E=3 and N=1, E>N (YES in S202), and the operation of the image forming apparatus 100 is not permitted (S203). That is, in all the configuration examples shown in Figs. 7, 8, and 9, the operation of the image forming apparatus 100 is not permitted.

[0036] For example, a case where the first set number N is 1 and the second set number M is 2 (N=1, M=2) will be described. In the first configuration example shown in FIG. 7, since the second option cassette 192 is connected to the image forming apparatus 100 (YES in S201), the number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the second set number M (S205). Since E=2 and M=2, E=M (NO in S205), and the operation of the image forming apparatus 100 is permitted (S207). In the second configuration example shown in FIG. 8 and the third configuration example shown in FIG. 9, the second option cassette 192 is not connected to the image forming apparatus 100 (NO in S201). The number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the first set number N (S202). Since the first set number N is 1, in the same manner as described above, in the second and third configuration examples, operation of the image forming apparatus 100 is not permitted (S203). That is, operation of the image forming apparatus 100 is permitted in the first configuration example shown in Fig. 7, but operation of the image forming apparatus 100 is not permitted in the second configuration example shown in Fig. 8 and the third configuration example shown in Fig. 9.

[0037] For example, a case will be described where the first set number N is 2 and the second set number M is 2 (N=2, M=2). Since the second set number M is 2, as described above, in the first configuration example shown in FIG. 7, E=2 and M=2, so E=M (NO in S205), and the operation of the image forming apparatus 100 is permitted (S207). In the second configuration example shown in FIG. 8, since the second option cassette 192 is not connected to the image forming apparatus 100 (NO in S201), the number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the first set number N (S202). Since E=2 and N=2, E=N (NO in S202), and the operation of the image forming apparatus 100 is permitted (S204). In the third configuration example shown in Fig. 9, since the second option cassette 192 is not connected to the image forming apparatus 100 (NO in S201), the number E of the first option cassettes 191 connected to the image forming apparatus 100 is compared with the first set number N (S202). Since E=3 and N=2, E>N (YES in S202), and the operation of the image forming apparatus 100 is not permitted (S203). That is, in the first configuration example shown in Fig. 7 and the second configuration example shown in Fig. 8, the operation of the image forming apparatus 100 is permitted, and in the third configuration example shown in Fig. 9, three In this configuration example, the operation of the image forming apparatus 100 is not permitted.

[0038] The second set number M may be the same as or different from the first set number N. The second set number M may be larger than the first set number N. This is because the installation floor area of ​​the second option cassette 192 is larger than the installation floor area of ​​the first option cassette 191, and therefore the image forming apparatus 100 becomes more stable when the second option cassette 192 is connected.

[0039] As described above, for image forming apparatus 100 with a configuration in which operation is permitted, the user is permitted to use it, and for image forming apparatus 100 with a configuration in which operation is not permitted, the user is not permitted to use it and is prompted to change the loading state of the optional cassette. In other words, by prohibiting the use of image forming apparatus 100 in a configuration in which there is a risk of it tipping over, it is possible to have the user change the configuration to a more stable one and use image forming apparatus 100.

[0040] It should be noted that the second option cassette 192 of this embodiment has a larger installation floor area than the first option cassette 191. However, the second option cassette 192 may be configured to be less likely to tip over than the first option cassette 191, and may be configured, for example, to have a lower center of gravity than the first option cassette 191.

[0041] (Optional cassette with casters) The second option cassette 192 may have any structure that is less likely to tip over than the first option cassette 191, and may have wheels with stoppers, for example. FIG. 10 is a cross-sectional view of the option cassettes with casters (194, 195). FIG. 10(a) is a cross-sectional view of the third option cassette 194. An electrical contact 94 is provided on the top of the third option cassette 194. Four casters 50 are provided on the bottom of the third option cassette 194. FIG. 10(b) is a cross-sectional view of the fourth option cassette 195. An electrical contact 95 is provided on the top of the fourth option cassette 195. A bottom plate 196 having a larger installation floor area than the installation floor area of ​​the bottom of the third option cassette 194 is provided on the bottom of the fourth option cassette 195. Four casters 50 are provided on the bottom of the bottom plate 196.

[0042] The third option cassette 194 can be connected to the bottom of the image forming apparatus 100 or the bottom of the first option cassette 191 connected to the image forming apparatus 100. The electrical contacts 94 of the third option cassette 194 are connected to the electrical contacts 90 of the image forming apparatus 100 or the electrical contacts 91b of the first option cassette 191. This allows the feeding stage detection unit 305 to detect that the third option cassette 194 is connected to the image forming apparatus 100. The fourth option cassette 195 can be connected to the bottom of the image forming apparatus 100 or the bottom of the first option cassette 191 connected to the image forming apparatus 100. The electrical contacts 95 of the fourth option cassette 195 are connected to the electrical contacts 90 of the image forming apparatus 100 or the electrical contacts 91b of the first option cassette 191. This allows the feeding stage detection unit 305 to detect that the fourth option cassette 195 is connected to the image forming apparatus 100.

[0043] The caster 50 has a wheel 51, a rotation shaft 52, a swivel shaft 53, and a stopper 54. The wheel 51 is rotatable about the rotation shaft 52 and swivels about the swivel shaft 53. The stopper 54 is movable between a position that prohibits the rotation and swivel of the wheel 51 and a position that permits the rotation and swivel of the wheel 51. The image forming apparatus 100 to which the third option cassette 194 or the fourth option cassette 195 is connected can be easily moved by the caster 50. After the image forming apparatus 100 is installed, the rotation and swivel of the caster 50 is prohibited by the stopper 54, so that the image forming apparatus 100 can be stably installed so as not to move.

[0044] The number of the first option cassettes 191 that are permitted to be connected to the image forming apparatus 100 when the third option cassette 194 is connected to the image forming apparatus 100 (the permitted number of connections) is set as a third set number (third threshold) G. The number of the first option cassettes 191 that are permitted to be connected to the image forming apparatus 100 when the fourth option cassette 195 is connected to the image forming apparatus 100 (the permitted number of connections) is set as a fourth set number (fourth threshold) K. The fourth set number K may be the same as the third set number G or may be different. The fourth set number K may be larger than the third set number G. This is because the installation floor area of ​​the fourth option cassette 195 is larger than the installation floor area of ​​the third option cassette 194, and therefore the image forming apparatus 100 becomes more stable when the fourth option cassette 195 is connected. The third set number G may be the same as the first set number N or may be different. The first set number N may be larger than the third set number G. This is because the first option cassette 191 is placed directly on the floor and is therefore more stable. The fourth set number K may be the same as or different from the second set number M. The second set number M may be greater than the fourth set number K. This is because the second option cassette 192 is placed directly on the floor and is therefore more stable.

[0045] In this embodiment, whether or not to permit operation of the image forming apparatus 100 is determined based on whether or not the first option cassette 191 to the fourth option cassette 195 are connected to the image forming apparatus 100. However, it may be determined whether or not optional devices such as an image reader (image reading device), a finisher (post-processing device), and an automatic document feeder are connected to the image forming apparatus 100, in addition to the optional cassettes. If there is a risk that the image forming apparatus 100 may fall over because an optional device (connected option) is connected to the image forming apparatus 100, the operation of the image forming apparatus 100 may be prohibited. [Explanation of symbols]

[0046] 100 Image forming apparatus 100a···Connection part 191...First option cassette 192...Second option cassette 180···Floor surface 300··CPU N: First setting number M: Second setting number E: The number of first option cassettes connected to the image forming device

Claims

1. An image forming apparatus for forming an image on a sheet, a connection section to which the first optional device and the second optional device are selectively and detachably connected; a determination unit that determines whether or not to prohibit operation of the image forming apparatus when the image forming apparatus is started up; Equipped with the first option device is connectable to the connection unit of the image forming device, the first optional device is connectable to another first optional device, thereby allowing a plurality of first optional devices to be stacked and connected to the image forming apparatus; the second optional device is installed on a floor surface and is connectable to the connection unit of the image forming apparatus or the first optional device; the determination unit prohibits the operation of the image forming apparatus when the second optional device is not connected to the image forming apparatus and the number of the first optional devices connected to the image forming apparatus is greater than a first threshold value; The image forming device is characterized in that the judgment unit prohibits the operation of the image forming device when the second optional device is connected to the image forming device and the number of the first optional devices connected to the image forming device is greater than a second threshold value.

2. 2. The image forming apparatus according to claim 1, wherein the second threshold value is equal to or greater than the first threshold value.

3. An image forming apparatus, an image forming unit that forms an image on a sheet; a connection section to which an optional device including a sheet storage section for storing sheets on which an image is formed by the image forming section is detachably connected; a determination unit that determines whether or not to prohibit an operation of the image forming apparatus; Equipped with the optional device is connectable to another optional device, whereby a plurality of optional devices can be stacked and connected to the image forming device; when a predetermined number of optional devices are connected to the image forming apparatus and all of the predetermined number of optional devices connected to the image forming apparatus are first optional devices, the determination unit determines to prohibit operation of the image forming apparatus; An image forming apparatus characterized in that, when the predetermined number of optional devices are connected to the image forming apparatus and the predetermined number of optional devices connected to the image forming apparatus include the first optional device and a second optional device installed on the floor surface and different from the first optional device, the judgment unit does not prohibit operation of the image forming apparatus.

4. 4. The image forming apparatus according to claim 1, wherein an installation floor area of ​​the second option device is larger than an installation floor area of ​​the first option device.

5. 5. The image forming apparatus according to claim 1, wherein a center of gravity of the second optional device is lower than a center of gravity of the first optional device.

6. 6. The image forming apparatus according to claim 1, wherein the second optional device is provided with wheels.

7. an operation unit for setting the operation of the image forming apparatus, The image forming apparatus according to any one of claims 1 to 6, characterized in that, when the judgment unit prohibits the operation of the image forming apparatus, a display is displayed on the operation unit prompting the user to change the loading state of the first optional device.

8. 8. The image forming apparatus according to claim 1, wherein the first optional devices are stacked vertically and connected below the image forming apparatus.

9. An image forming apparatus as described in any one of claims 1 to 8, characterized in that each of the first optional device and the second optional device is a feeding cassette having a sheet storage section for storing sheets and a feeding section for feeding sheets one by one from the sheet storage section.

Images