Image forming system

Abstract

To properly shut down the supply of power to a load provided in another housing when a cover of one housing of the two adjacent housings is opened.SOLUTION: A first device comprises: a first power source; a first door; a first interlock switch which is switched between on and off in conjunction with the opening / closing of the first door; and a first supply system which supplies the DC voltage generated by the first power source to a first load. The first device further comprises a first switch element which switches between the supply possible state and the supply inhibition state of the DC voltage by the first supply system. The first switch element switches between the supply possible state and the supply inhibition state in conjunction with on / off of the first interlock switch. A second device comprises a second load that can be accessed by a user from the inside of a first housing. The supply / shut down of the operation voltage required for operating the second load is switched in conjunction with on / off of the first switch element.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an image forming system.

Background Art

[0002] When a maintenance cover for a user to access the inside of an image forming apparatus is opened, the image forming apparatus includes an interlock mechanism that cuts off the power supply to the drive source. According to Patent Document 1, it has been proposed to cut off the power supply to the load by a relay that turns off and on in conjunction with the opening and closing of the cover.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to efficiently develop a plurality of different types of image forming apparatuses, it is conceivable to divert a fixing apparatus developed on the premise of being connected to a certain type of image transfer apparatus to another type of image transfer apparatus. However, when the height of the discharge port of one type of image transfer apparatus is different from the height of the discharge port of another type of image transfer apparatus, this fixing apparatus cannot be connected to the other type of image transfer apparatus. Therefore, a transport apparatus for relaying the sheet between the other type of image transfer apparatus and the fixing apparatus is required. Such a transport apparatus transports a sheet with an unfixed toner image thereon. If the height of the opening of the communication portion that communicates the transport apparatus and the fixing apparatus is insufficient, the toner image may contact the edge of the opening and be disturbed. Therefore, the opening is designed to be large.

[0005] Such conveying devices also require a maintenance door (cover) to remove jammed sheets. However, if the opening of the communication section is large, when the cover of the conveying device is opened, a user may be able to access the load of the fixing device from the inside of the conveying device housing through the communication section. This could lead to a failure of the load. Here, a conveying device and a fixing device were given as an example, but similar problems arise between multiple adjacent housings. Therefore, the present invention aims to appropriately shut off the power supply to the load provided in one of two adjacent housings when the cover of the other housing is opened. [Means for solving the problem]

[0006] The present invention, for example, A first apparatus comprising a first transport means for transporting a sheet on which an unfixed toner image has been transferred, A second device connected to the first device and equipped with fixing means for fixing the toner image onto a sheet discharged from the first device, An image forming system having, The first device is, A first housing having a first opening through which a sheet conveyed to the second device by the first conveying means passes, A first motor that drives the first transport means, A first power supply that supplies power to the first motor, A first door is opened to expose the interior of the first device, The first electric Connect the power source to the first motor. first It is provided in the path, and when the first door is closed, first When the power supply and the first motor are connected, and the first door is open, the first It has a first switch that switches to a second state in which the power supply and the first motor are cut off, The second device is, A second housing is provided opposite the first opening and has a second opening through which the sheet discharged from the first device passes, Second power supply and A second door is opened to expose the interior of the second device, Connected to the first power supply via the first switch, In a state where the first switch is in the first state, From the aforementioned first power supply a first load to which power is supplied, the first switch The first route provided independently of , from either the commercial power supply or the second power supply a second load to which power is supplied, A second switch is provided in the second path connecting the first power source and the second load, and when the second door is closed, it enters a first state in which the first power source and the second load are connected, and when the second door is open, it switches to a second state in which the first power source and the second load are disconnected. and has when the first door is open, the user can access the inside of the second device from the inside of the first device through the first opening and the second opening, The first load and provides an image forming system characterized in that when the first switch is in the first state and power is supplied to the first load, With both the first door and the second door closed, when the first door is opened and the first switch switches to the second state, the power supply to the first load is cut off, but the power supply to the second load is not cut off. Furthermore, the second switch is in the first state and power is supplied to the second load. in the state where The second door remains closed. According to the present invention, when the cover of one of two adjacent housings is opened, it is possible to appropriately cut off the power supply to the load provided in the other housing.

Advantages of the Invention

[0007] According to the present invention, when the cover of one of two adjacent housings is opened, it is possible to appropriately cut off the power supply to the load provided in the other housing.

Brief Description of the Drawings

[0008] [Figure 1] A diagram showing an image forming system. [Figure 2] A diagram for explaining the opening and closing of a maintenance door. [Figure 3] A diagram for explaining the interlock mechanism of Example 1. [Figure 4] A diagram for explaining the interlock mechanism of Example 2. <00​​​​​Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0010] <Image forming system> As shown in FIG. 1, the image forming system 1 of the present embodiment has three devices. The image forming apparatus 100 transfers a toner image onto a sheet P and discharges the sheet P to the conveying apparatus 110. The conveying apparatus 110 is a relay apparatus that receives the sheet P carrying the unfixed toner image from the image forming apparatus 100 and delivers it to the fixing apparatus 120. The fixing apparatus 120 applies heat and pressure to the sheet P and the toner image received from the fixing apparatus 120 to fix the toner image on the sheet P. As shown in FIG. 1, the housing of the image forming apparatus 100, the housing of the conveying apparatus 110, and the housing of the fixing apparatus 120 are provided separately.

[0011] The height of the sheet discharge port of the image forming apparatus 100 does not match the height of the sheet receiving port of the fixing apparatus 120. This is because the fixing apparatus 120 is designed for another image forming apparatus different from the image forming apparatus 100. In order to make the fixing apparatus 120 usable also with the image forming apparatus 100, it is necessary to absorb the difference in height between the sheet discharge port of the image forming apparatus 100 and the sheet receiving port of the fixing apparatus 120. The conveying apparatus 110 is provided to absorb this difference in height.

[0012] ●Image forming apparatus The image forming apparatus 100 will now be described in detail. The image forming apparatus 100 includes image forming units PY, PM, PC, and PK. Image forming unit PY forms a yellow toner image. Image forming unit PM forms a magenta toner image. Image forming unit PC forms a cyan toner image. Image forming unit PK forms a black toner image. A full-color image is formed by superimposing the four toner images. In this embodiment, the letters Y, M, C, and K added to the end of the reference numerals indicate the toner color. When matters common to the four colors are described, the letters Y, M, C, and K are omitted from the reference numerals.

[0013] The image forming unit P includes a photoreceptor drum 10, a charger 11, an exposure unit 3, a developer unit 12, a drum cleaner 13, and the like. The photoreceptor drum 10 is an image carrier that rotates while carrying an electrostatic latent image or a toner image. The charger 11 uniformly charges the surface of the photoreceptor drum 10. The exposure unit 3 irradiates the surface of the photoreceptor drum 10 with laser light corresponding to the image signal to form an electrostatic latent image corresponding to the image signal. The developer unit 12 deposits toner onto the electrostatic latent image to form a toner image. The primary transfer unit 14 transfers the toner image from the photoreceptor drum 10 to the intermediate transfer belt 20. The drum cleaner 13 cleans the toner remaining on the surface of the photoreceptor drum 10.

[0014] The intermediate transfer belt 20 is an intermediate transfer body or image carrier that rotates while being stretched between two tension rollers 21 and a secondary transfer inner roller 22. One of the two tension rollers 21 and the secondary transfer inner roller 22 may be a drive roller that drives the intermediate transfer belt 20. The intermediate transfer belt 20 transports the toner image to the secondary transfer section. The secondary transfer section is formed by the secondary transfer inner roller 22 and the secondary transfer outer roller 23. In particular, the secondary transfer outer roller 23 transfers the toner image from the intermediate transfer belt 20 to the sheet P. The belt cleaner 24 cleans the toner remaining on the surface of the intermediate transfer belt 20.

[0015] The image forming apparatus 100 has one or more storage compartments 30 capable of accommodating a large number of sheets P. The separation belt 31 separates the sheet P located at the top of the sheet bundle stored in the storage compartment 30 from the sheet bundle and feeds it to the paper feed roller 32. The paper feed roller 32 transports the sheet P and passes it to the transport roller 33. The transport roller 33 further transports the sheet P downstream in the transport direction and passes it to a plurality of registration rollers 34. The plurality of registration rollers 34 form a sheet steering mechanism. The sheet steering mechanism is a mechanism that aligns the longitudinal or transverse direction of the sheet P parallel to the transport direction of the sheet P. This process may also be called skew correction. The plurality of registration rollers 34 transport the sheet P so that the timing of the toner image arriving at the secondary transfer section coincides with the timing of the sheet P arriving at the secondary transfer section.

[0016] Downstream of the secondary transfer section, conveyor belt units 35 and 36 are provided. The conveyor belt units 35 and 36 further convey the sheet P downstream. Here, the conveyor belt units 35 and 36 may convey the sheet P while adsorbing it with negative pressure. Negative pressure is generated, for example, by adsorbing air. The reason for adsorbing the sheet P to the conveyor belt units 35 and 36 with negative pressure is to prevent disruption of the unfixed toner image on the sheet P even when the sheet P is conveyed at high speed. The conveyor belt unit 36 ​​then hands over the sheet P to the conveying device 110.

[0017] ● Conveying device The conveyor belt unit 40 of the conveyor device 110 conveys the sheet P received from the image forming apparatus 100 to the fixing device 120. The conveyor belt unit 40 may also convey the sheet P while suctioning it. The housing of the conveyor device 110 is provided with an opening 42 that functions as a sheet discharge port. The housing of the fixing device 120 is provided with an opening 50 that functions as a sheet receiving port. The openings 42 and 50 face each other and form a communication section 43. In other words, the sheet P is conveyed from the conveyor device 110 to the fixing device 120 via the communication section 43. Here, an unfixed toner image exists on the sheet P being conveyed from the conveyor device 110 to the fixing device 120. The opening area of ​​the opening 42 is designed to be sufficiently large so that the edge of the opening 42 does not come into contact with the toner image.

[0018] ● Fixing device The fixing device 120 has a fuser 51. The fuser 51 has a heating belt 53. The heating belt 53 is stretched and rotated by a heating roller 52, a tension roller 54, and a fixing roller 55. A heater 56 is provided inside the heating roller 52. The heater 56 heats the heating belt 53 and maintains the temperature of the heating belt 53 at a predetermined fixing temperature. The fixing roller 55 and the pressure roller 57 form a fixing nip. The fixing roller 55 and the pressure roller 57 rotate while gripping the heating belt 53. The fixing nip applies heat and pressure to the sheet P to fix the toner image onto the sheet P.

[0019] In single-sided printing mode, the sheet P is discharged outside the fuser 120 by the paper discharge roller 58. An output tray or post-processing device may be connected to the outside of the fuser 120. The post-processing device performs post-processing (e.g., binding, stitching, perforation) on the sheet P.

[0020] In double-sided printing mode, the sheet P with the toner image formed on the first side is returned to the image forming apparatus 100 via the transport device 110. That is, the reversing roller 59 pulls in the sheet P and hands it over to the transport roller 60, reversing the front and back sides of the sheet P (switchback reversal). The transport roller 60 transports the sheet P and hands it over to the transport roller 41 of the transport device 110. The transport roller 41 further transports the sheet P and hands it over to the transport roller 37 of the image forming apparatus 100. The transport roller 37 transports the sheet P and hands it over to the transport roller 33. The transport roller 33 hands the sheet P over to the registration roller 34. The registration roller 34 transports the sheet P again to the secondary transfer section. The secondary transfer section transfers the toner image to the second side of the sheet P. After that, the sheet P is discharged outside the fuser 120 via the transport device 110 and the fuser 120.

[0021] ● Appearance of the image forming apparatus Figure 2(A) shows covers 201-204 in the closed position. Covers 201 and 202 are maintenance doors that form part of the housing 200 of the image forming apparatus 100. Covers 201 and 202 are opened by the user when a jam occurs in the sheet P. Once the sheet P is removed, covers 201 and 202 are closed.

[0022] The cover 203 forms part of the housing 210 of the conveying device 110. If a jam occurs in the conveying device 110 with sheet P, the user opens the cover 203 to remove sheet P.

[0023] The cover 204 forms part of the housing 220 of the fixing device 120. If a jam occurs in the fixing device 120, the user opens the cover 204 to remove the sheet P.

[0024] Figure 2(B) shows covers 203 and 204 in the open position. Figure 2(C) shows cover 203 open but cover 204 closed. As shown in Figures 2(B) and 2(C), the housing 210 is provided with an opening 42. When cover 203 is opened, a user can access some of the loads of the fixing device 120 (e.g., the heated belt 53 stretched over the fixing roller 55) from the inside of the housing 210 of the conveying device 110. This is due to the large opening area of ​​the opening 42. If a user touches the heated belt 53 through the opening 42, the fixing unit 51, including the heated belt 53, may malfunction. Therefore, when cover 203 is opened, the power supply should be cut off not only to the loads located inside the conveying device 110 but also to some of the loads of the fixing device 120. Some of the loads of the fixing device 120 include at least the fixing unit 51. In other words, the power supply to the motor driving the heated belt 53 is cut off.

[0025] <Interlock mechanism> [Example 1] ● Interlock mechanism of image forming apparatus As shown in Figure 3, the image forming apparatus 100 is supplied with AC voltage from a commercial AC power source via a power cord 300. A filter 301 is connected to the power cord 300. The filter 301 removes noise from the AC voltage and supplies AC voltage to the 12V power supply 302 and the 24V power supply 303. The 12V power supply 302 is a power supply circuit that converts AC voltage to a DC voltage of +12V. The 24V power supply 303 is a power supply circuit that converts AC voltage to a DC voltage of +24V. Hereinafter, +12V will be denoted as +12V_M in the section upstream of switch SW1 and as +12VIL_M in the section downstream of switch SW2. +12V_M and +12VIL_M may be understood as indicating the power supply system for supplying +12V. Similarly, the DC voltage +24V is denoted as +24V_M in the section upstream of relay RL1 and as +24VIL_M in the section downstream of relay RL1. +24V_M and +24VIL_M can be understood as indicating the power supply system for supplying +24V. The DC voltages +12V_M and +24V_M are input to relay unit 304.

[0026] The relay unit 304 converts the +12V_M output from the 12V power supply 302 to a predetermined DC voltage (e.g., 5V, 3.3V, etc.) and supplies it to the controller 305. +12V_M is connected to one end of switch SW1. The other end of switch SW1 is connected to one end of switch SW2. The other end of switch SW2 applies +12VIL_M to one end of the coil of relay RL1. Switch SW1 is an interlock switch that turns on and off in conjunction with the opening and closing of cover 201. Switch SW2 is an interlock switch that turns on and off in conjunction with the opening and closing of cover 202. Note that switches SW1, SW2 and relay RL1 only need to be able to cut off the power supply to the load when covers 201 and 202 are opened. In other words, when either cover 201 or cover 202 is opened, the two contacts of relay RL1 open and cut off the supply of DC voltage +24VIL_M. When both covers 201 and 202 are closed, switches SW1 and SW2 are both turned on, the two contacts of relay RL1 close, and a DC voltage of +24VIL_M becomes available.

[0027] Thus, the +12VIL_M supplied via switches SW1 and SW2 is used as the operating voltage for the coil of relay RL1. The collector of transistor Tr1 is connected to the other end of the coil of relay RL1. The emitter of transistor Tr1 is grounded. The base of transistor Tr1 is connected to controller 305.

[0028] The DC voltage +24V_M generated by the 24V power supply 303 is applied to the upstream contact of relay RL1, one end of the coil of relay RL2, and the upstream contact of relay RL2. The collector of transistor Tr2 is connected to the other end of the coil of relay RL2. The emitter of transistor Tr2 is grounded. The base of transistor Tr2 is connected to controller 305.

[0029] The downstream contacts of relay RL1 are connected to the exposure unit 3, high-voltage power supply 2, and motors M1-M6 to supply +24VIL_M. Motor M1 drives the photoreceptor drum 10. Motor M2 drives the developing sleeve of the developer unit 12. Motor M3 drives the intermediate transfer belt 20. Motor M4 drives the registration roller 34. Motor M5 drives the transport belt units 35 and 36. Motor M6 drives the transport roller 37. The high-voltage power supply 2 generates the charging voltage, developing voltage, and transfer voltage.

[0030] The downstream contacts of relay RL2 are connected to motors M7 and M8 to supply +24V_M. Motor M7 drives the separation belt 31 and the paper feed roller 32. Motor M8 drives the transport roller 33.

[0031] Controller 305 controls the power supply to the load by outputting control signals to the bases of transistors Tr1 and Tr2. When Controller 305 starts up, it turns on transistors Tr1 and Tr2 and supplies power to motors M1 to M8, the exposure unit 3, and the high-voltage power supply 2. Controller 305 performs image formation by outputting operation command signals to the exposure unit 3, the high-voltage power supply 2, and motors M1 to M8. Controller 305 performs serial communication with the controller 315 of the transport device 110 and the controller 325 of the fixing device 120 to control the transport device 110 and the fixing device 120.

[0032] ● Interlock mechanism for conveying equipment The transport device 110 is connected to the commercial AC power supply via a power cord 310. A filter 311 is connected to the power cord 310. The filter 311 removes noise from the AC voltage and supplies AC voltage to the 12V power supply 312 and the 24V power supply 313. The 12V power supply 312 is a power supply circuit that converts AC voltage to DC voltage +12V. The 24V power supply 313 is a power supply circuit that converts AC voltage to DC voltage +24V. Hereinafter, the DC voltage +12V will be denoted as +12V_D in the section upstream of switch SW3 and as +12VIL_D in the section downstream of switch SW3. +12V_D and +12VIL_D may be understood as indicating the power supply system for supplying +12V. Similarly, the DC voltage +24V will be denoted as +24V_D in the section upstream of relay RL3 and as +24VIL_D in the section downstream of relay RL3. +24V_D and +24VIL_D can be understood as indicating the power supply system for supplying +24V. The DC voltages +12V_D and +24V_D are input to relay unit 314.

[0033] The relay unit 314 converts the DC voltage +12V_D output from the 12V power supply 312 to a predetermined DC voltage (5V, 3.3V, etc.) and supplies it to the controller 315. The relay unit 314 applies +12V_D to one end of switch SW3. Switch SW3 is an interlock switch that turns on and off in conjunction with the opening and closing of the cover 203. The other end of switch SW3 supplies +12VIL_D to one end of the coil of relay RL3. In this way, +12VIL_D is applied to the cover 203 If it is closed, it can be supplied, cover 203 opens This is a DC voltage that, if present, will have its supply prohibited (shut off).

[0034] +12VIL_D is used as the operating voltage for the coil of relay RL3. The collector of transistor Tr3 is connected to the other end of the coil. The 24V power supply 313 is connected to the upstream contact of relay RL3, applying +24V_D to the upstream contact of relay RL3. A DC voltage of +24VIL_D is generated at the downstream contact of relay RL3. The downstream contact of relay RL3 is connected not only to motors M11 and M12, but also to motor M21 of the fixing device 120. The downstream contact of relay RL3 supplies a DC voltage of +24VIL_D to these.

[0035] The emitter of transistor Tr3 is grounded. The base of transistor Tr3 is connected to controller 315. Controller 315 controls the supply of +24VIL_D to the load by outputting a control signal to the base of transistor Tr3. For example, when controller 315 receives a start request from controller 305, it turns on transistor Tr3 and supplies +24VIL_D to motors M11, M12, etc. When cover 203 is opened, the +24VIL_D is cut off by switch SW3 and relay RL3.

[0036] ●Interlock mechanism of the fixing device The fixing device 120 is connected to the commercial AC power supply via a power cord 320. A filter 321 is connected to the power cord 320. The filter 321 removes noise from the AC voltage and supplies the AC voltage to the 12V power supply 322, the 24V power supply 323, and the upstream contact of the relay RL6. The 12V power supply 322 is a power supply circuit that converts the AC voltage to a DC voltage of +12V. The 24V power supply 323 is a power supply circuit that converts the AC voltage to a DC voltage of +24V. Hereinafter, the DC voltage of +12V will be denoted as +12V_F in the section upstream of switch SW4 and as +12VIL_F in the section downstream of switch SW4. +12V_F and +12VIL_F may be understood as indicating the power supply system for supplying +12V. Similarly, the DC voltage +24V is denoted as +24V_F in the section upstream of relay RL4 and as +24VIL_F in the section downstream of relay RL4. +24V_F and +24VIL_F can be understood as indicating the power supply system for supplying +24V. The DC voltages +12V_F and +24V_F are input to relay unit 324. A heater 56 is connected to the downstream contact of relay RL5 via drive circuit 326.

[0037] The relay unit 324 converts the +12V_F output from the 12V power supply 322 to a predetermined DC voltage (5V, 3.3V, etc.) and supplies it to the controller 325. The relay unit 324 supplies +12V_F to one end of the switch SW4. Switch SW4 is an interlock switch that turns on and off in conjunction with the opening and closing of the cover 204. The other end of switch SW4 is connected to one end of the coil of relay RL4 and one end of the coil of relay RL5. In other words, +12V_F is used as the operating voltage of the coil of relay RL4 and the coil of relay RL5. When the cover 204 is opened, the supply of +12V_F is cut off, so both relays RL4 and RL5 turn off (turn off).

[0038] The other end of the coil of relay RL4 is connected to the collector of transistor Tr4. The other end of the coil of relay RL5 is connected to the collector of transistor Tr5. The emitters of transistors Tr4 and Tr5 are grounded. The bases of transistors Tr4 and Tr5 are connected to controller 325.

[0039] +24V_F is applied to the upstream contact of relay RL4. The downstream contact of relay RL4 is connected to motors M22 to M24 to supply +24VIL_F. Motor M22 drives the paper discharge roller 58. Motor M23 drives the reversing roller 59. Motor M24 drives the transport roller 60. Here, motor M21 is the motor that drives the fuser 51. The operating voltage of motor M21 is +24VIL_D supplied from the transport device 110.

[0040] The controller 325 controls the power supply to the load by outputting control signals to the bases of transistors Tr4 and Tr5. Upon receiving a start request from the controller 305, the controller 325 turns on transistors Tr4 and Tr5 to allow power supply to the load. For example, the controller 325 controls the power to the heater 56 through transistor Tr5, relay RL5, and drive circuit 326 to maintain the temperature of the heating belt 53 at a target temperature.

[0041] ●Details of power cut-off when the cover is opened As described above, opening and closing the cover 201 of the image forming apparatus 100 turns switch SW1 off and on. Opening and closing the cover 202 turns switch SW2 off and on. Since switches SW1 and SW2 are connected in series, when either switch SW1 or SW2 is turned off, the supply of +12VIL_M is interrupted (stopped). As a result, the coil of relay RL1 loses its operating voltage, and the load connected to the downstream contact of relay RL1 is interrupted from receiving the operating voltage of +24VIL_M.

[0042] When the cover 203 of the transport device 110 is opened, switch SW3 is turned off, and the supply of +12VIL_D is cut off. The coil of relay RL3 loses its operating voltage of +12VIL_D, and relay RL3 turns off. Motors M11 and M12, and motor M21 of the fixing device 120, which are connected to the downstream contacts of relay RL3, lose their operating voltage of +24VIL_D and stop.

[0043] When the cover 204 of the fixing device 120 is opened, switch SW4 turns off. As a result, relays RL4 and RL5 lose their operating voltage of +12VIL_F and turn off. Motors M22 to M24 connected to the downstream contacts of relay RL4 lose their operating voltage of +24VIL_F. The drive circuit 326 and heater 56 connected to the downstream contacts of relay RL5 also lose their AC voltage. However, motor M21 does not lose its operating voltage even when the cover 204 is opened.

[0044] According to Embodiment 1, there is a communication section 43 that allows access from the inside of the housing 210 of the conveying device 110 to the inside of the housing 220 of the fixing device 120. Therefore, when the cover 203 of the conveying device 110 is opened, the power supply to some of the loads of the fixing device 120 (e.g., the motor M21 that drives the heating belt 53) is cut off. This prevents failure of some of the loads provided in the fixing device 120.

[0045] [Example 2] Figure 4 shows the interlock mechanism of Example 2. As can be seen by comparing it with Figure 3, the parts enclosed by the dashed lines in Figure 4 are the changes. The explanation of the parts common to Example 1 in Example 2 is omitted.

[0046] As shown in Figure 4, the motor M21 of the fixing device 120 is supplied with an operating voltage of +24VIL_F via relay RL6. Here, +24VIL_D is supplied as the operating voltage from the transport device 110 to one end of the coil of relay RL6. The collector of transistor Tr6 is connected to the other end of the coil. The emitter of transistor Tr6 is grounded. The base of transistor Tr6 is connected to controller 325. Controller 325 controls the start and stop of rotation of motor M21 via transistor Tr6. The upstream contact of relay RL6 is connected to the downstream contact of relay RL4 and is supplied with +24VIL_F. The downstream contact of relay RL6 is connected to motor M21.

[0047] When the cover 203 of the transport device 110 is opened, the coil of relay RL6 loses its operating voltage of +24VIL_D. As a result, relay RL6 cuts off the supply of +24VIL_F, and motor M21 loses its operating voltage of +24VIL_F.

[0048] In Example 1, the operating voltage of motor M21 was +24VIL_D, but in Example 2, the operating voltage was changed to +24VIL_F. However, both Example 1 and Example 2 share the common characteristic that when +24VIL_D is interrupted, motor M21 loses its operating voltage.

[0049] In Example 1, the motor M21 did not lose operating voltage even when the cover 204 of the fixing device 120 was opened. However, in Example 2, the motor M21 also loses operating voltage when the cover 204 is opened. In Example 1, when the cover 204 of the fixing device 120 is opened, the fixing device 51 may require some kind of protective member to reduce access to the heating belt 53 of the fixing device 51. In Example 2, there is the advantage that such a protective member can be omitted.

[0050] <Other> In the embodiment described above, when the cover 203 of the conveying device 110 is opened, the power to the motor of the fixing device 120 is cut off. However, the load is not limited to the motor, but may also be a heater (e.g., heater 56). In other words, when the cover 203 of the conveying device 110 is opened, the power to the heater of the fixing device 120 may be cut off. Also, when the cover 203 of the conveying device 110 is opened, the power to both the heater and the motor of the fixing device 120 may be cut off. For example, according to Figure 3, power is supplied to the heater 56 via relay RL5. Therefore, when the cover 203 of the conveying device 110 is opened, relay RL5 should be switched from on to off. A way to achieve this is to stop supplying the operating voltage +12VIL_F applied to one end of the coil of relay RL5 when the cover 203 of the conveying device 110 is opened. For example, the +12VIL_D or +24VIL_D generated by the conveying device 110 may be supplied as the operating voltage for the coil of relay RL5 instead of +12VIL_F. If +24VIL_D is used, a resistor circuit (voltage divider circuit) or regulator may be used to step down +24VIL_D to +12V. In addition, a power line will be added to supply +12VIL_D or +24VIL_D from the conveying device 110 to one end of the coil of relay RL5.

[0051] Alternatively, when the cover 203 of the transport device 110 is opened, the transistor Tr5, which is a switching element connected to the other end of the coil of the relay RL5, may be switched from on to off. To switch transistor Tr5 off, controller 315 notifies controller 325 via controller 305 that the cover of the transport device 110 has been opened. When controller 325 is notified that the cover 203 of the transport device 110 has been opened, it controls the base signal of transistor Tr5 to switch transistor Tr5 off. This stops the power supply to the heater 56.

[0052] <Technical concepts derived from examples> [Perspective 1, 16] As shown in Figure 1, the transport device 110 is located downstream of the image forming apparatus 100 in the sheet transport direction and is an example of a first apparatus having a first housing. The fixing device 120 is an example of a second apparatus having a second housing that can be connected to the first housing and is supplied with sheets from the first apparatus. The 12V power supply 312 and the 24V power supply 312 are examples of first power supplies that convert AC voltage supplied from an AC power supply to DC voltage. Motors M11 and M12 are examples of first loads located inside the first housing. The cover 203 is an example of an openable and closable first door that forms part of the first housing. Switch SW3 is an example of a first interlock switch that switches between on and off in conjunction with the opening and closing of the first door. +24VIL_D may be understood as a first supply system that supplies DC voltage (e.g., +24V) generated by the first power supply to the first load. Relay RL3 is an example of a first switch element that switches between a state where DC voltage can be supplied by the first supply system and a state where it cannot be supplied. The first switch element only needs to be configured to switch between a supply-enabled state and a supply-disabled state in conjunction with the on / off state of at least the first interlock switch. The fixing roller 55, heating belt 53, and motor M21 are examples of a second load provided inside the second housing. As shown in Figure 2(C), the second load is located inside the second housing. However, when the first door (e.g., cover 203) is opened, the second load becomes accessible to the user from the inside of the first housing through the communication section between the first and second housings. As shown in Figures 3 and 4, the supply and interruption of the operating voltage necessary for the operation of the second load are switched in conjunction with the on / off state of the first switch element provided in the first device. In other words, when the first door is opened, the operating voltage necessary for the operation of the second load is interrupted. In this way, when the cover of one of two adjacent housings is opened, it is possible to appropriately interrupt the power supply to the load provided in the other housing.

[0053] [Perspective 2] The operating voltage of the second load (e.g., +24V) may be supplied from the first power supply of the first device through the first power supply system (e.g., +24VIL_D). When the first switch element (e.g., relay RL3) provided in the first device is switched from on to off, the first power supply system switches from a supply-enabled state to a supply-disabled state. As a result, the supply of operating voltage to the second load through the first power supply system may be stopped. In this way, since power is supplied to the load of the second device from the first device, the load of the second device can be stopped by the interlock mechanism of the first device.

[0054] [Perspective 3] The first switching element may include a switching device (e.g., relay RL3) that operates using a DC voltage supplied from the first power supply. The switching device may switch from a supply-enabled state to a supply-deprived state when the DC voltage (e.g., +12VIL_D) supplied from the first power supply is interrupted by the first interlock switch.

[0055] [Perspective 4-6] The switching device may be a relay (e.g., relay RL3) having two contacts and a coil that opens and closes the two contacts. A DC voltage supplied from the first power supply may be applied to one end of the coil as the operating voltage. A switch (e.g., transistor Tr3) may be further provided connected to the other end of the coil. Such a switch can interrupt the power supply to the load independently of the interlock mechanism. The switching device may be a semiconductor switch (field-effect transistor (FET)).

[0056] [perspective 7] The first power supply may have a first power supply circuit (e.g., 24V power supply 313) that generates a first DC voltage and a second power supply circuit (e.g., 12V power supply 312) that generates a second DC voltage. The first power supply circuit is connected to a first supply system (e.g., +24V_D, +24VIL_D) and configured to supply the first DC voltage to the first supply system. The first switching element (e.g., relay RL3) is configured to operate with the second DC voltage supplied via a first interlock switch. When the supply of the second DC voltage to the first switching element is interrupted by the first interlock switch, the supply of the first DC voltage via the first supply system is interrupted by the first switching element.

[0057] [Perspective 8] The 12V power supply 322 and 24V power supply of the fixing device 120 are examples of second power supplies that convert the AC voltage supplied from the AC power supply to a DC voltage (e.g., +24V). +24VIL_F may be understood as a second supply system that supplies the DC voltage generated by the second power supply to the second load. As shown in Figure 4, relay RL6 is an example of a second switch element that switches between a state where the DC voltage from the second supply system can be supplied and a state where it cannot be supplied. The second switch element is configured to switch between the supply-enabled state and the supply-disabled state in conjunction with at least the on / off state of the first switch element. In this way, even in cases where power is not directly supplied from the first device to the load of the second device, it is possible to stop the load of the second device when the first door is opened.

[0058] [Perspective 9] The second switching element may include a switching device (e.g., relay RL6) that operates using a DC voltage supplied from the second power supply. The switching device may be switched from on to off by the first interlock switch interrupting the DC voltage supplied from the first power supply. This may cause the switching device to interrupt the supply of DC voltage from the second power system to the second load.

[0059] [Perspectives 10-12] The switching device may be a relay (e.g., relay RL6) having two contacts and a coil for opening and closing the two contacts. The DC voltage supplied from the first power supply may be applied to one end of the coil. That is, the relay may turn off when the DC voltage supplied from the first power supply is interrupted by the interlock mechanism of the first device. The device may further have a switch (e.g., transistor Tr6) connected to the other end of the coil. Such a switch can control the power supply to the load independently of the interlock mechanism. The switching device may also be a semiconductor switch (e.g., FET).

[0060] [Perspective 13] The second device (e.g., a fixing device 120) may include a second power supply connected to an AC power supply, and a second load (e.g., a motor M21) and a third load (e.g., motors M22-M24) located inside the second housing. The second device may also include an openable and closable second door (e.g., a cover 204) forming part of the second housing, and a second interlock switch (e.g., a switch SW4) that switches on and off in conjunction with the opening and closing of the second door. +24VIL_F may be understood as a second supply system that supplies power generated by the second power supply to the third load. Relay RL4 is an example of a second switch element that switches between a power supply enabled state and a power supply disabled state by the second supply system. The second switch element may be configured to switch between the power supply enabled state and the power supply disabled state in conjunction with the on / off state of at least the second interlock switch. The second load is switched between supplying and cutting off the operating voltage necessary for the operation of the second load (e.g., motor M21) in conjunction with the on / off state of the first switch element provided in the first device. Thus, the first and second devices may have independent interlock mechanisms. On the other hand, the second load of the second device may have its operating voltage interrupted by the interlock mechanism of the first device.

[0061] [Perspective 14] The second power supply may include a third power supply circuit (e.g., 24V power supply 323) that generates a third DC voltage and a fourth power supply circuit (e.g., 12V power supply 322) that generates a fourth DC voltage. The third power supply circuit is connected to a second supply system (+24V_F, +24VIL_F) and configured to supply the third DC voltage to the second supply system. The second switching element (e.g., relay RL6) is configured to operate with the second DC voltage supplied via a first interlock switch (e.g., switch SW3). When the supply of the second DC voltage (e.g., +24VIL_D) to the second switching element is interrupted by the first interlock switch, the supply of the third DC voltage via the second supply system is interrupted by the second switching element.

[0062] [Perspective 15] As shown in Figure 4, the operating voltage required for the second load to operate may be a third DC voltage via a second power supply system. The supply of the third DC voltage to the second load may be interrupted by a second interlock switch (e.g., switch SW4) which cuts off the supply of the third DC voltage to the second switch element (e.g., relay RL6). In this way, the supply of the operating voltage to the second load may be independently interrupted by two interlock mechanisms.

[0063] [Perspective 17] As shown in Figure 1, the first apparatus may include a transport device 110. The second apparatus may include a fixing device 120 for fixing the toner image transferred to the sheet onto the sheet. The fixing device 120 includes a second load. The first and second apparatuses may be two adjacent post-processing devices. The first and second apparatuses may also be two adjacent sheet feeders for feeding sheets to the image forming apparatus 100.

[0064] The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, claims are attached to disclose the scope of the invention. [Explanation of symbols]

[0065] 1: Image forming system, 100: Image forming apparatus, 110: Transport apparatus, 120: Fixing apparatus

Claims

1. A first apparatus comprising a first transport means for transporting a sheet on which an unfixed toner image has been transferred, A second device connected to the first device and equipped with fixing means for fixing the toner image onto a sheet discharged from the first device, An image forming system having, The first device is, A first housing having a first opening through which a sheet conveyed to the second device by the first conveying means passes, A first motor that drives the first transport means, A first power supply that supplies power to the first motor, A first door is opened to expose the interior of the first device, The system includes a first switch provided in a first path connecting the first power supply and the first motor, which switches to a first state where the first power supply and the first motor are connected when the first door is closed, and to a second state where the first power supply and the first motor are disconnected when the first door is open. The second device is, A second housing is provided opposite the first opening and has a second opening through which the sheet discharged from the first device passes, Second power supply and A second door is opened to expose the interior of the second device, A first load connected to the first power supply via the first switch, and in the state where the first switch is in the first state, is supplied with power from the first power supply. A second load, which is powered by either the commercial power supply or the second power supply, independently of the first path on which the first switch is provided, The system includes a second switch provided in a second path connecting the first power source and the second load, which switches to a first state where the first power source and the second load are connected when the second door is closed, and to a second state where the first power source and the second load are disconnected when the second door is open. With the first door open, a user can access the first load inside the second device from inside the first device through the first opening and the second opening. An image forming system characterized in that, when both the first door and the second door are closed, the first switch is in the first state and power is supplied to the first load, and the second switch is in the first state and power is supplied to the second load, if the first door is opened while the second door remains closed and the first switch switches to the second state, the power supply to the first load is interrupted, but the power supply to the second load is not interrupted.

2. The aforementioned first power supply is A first power supply circuit that generates the first DC voltage, Includes a second power supply circuit that generates a second DC voltage, The first power supply circuit is connected to the first motor via the first switch. The second DC voltage generated by the second power supply circuit is used as the operating voltage of the first switch. The image forming system according to claim 1, characterized in that when the supply of the second DC voltage to the first switch is interrupted while the first switch is in the first state, the first switch switches to the second state.

3. The image forming system according to claim 1 or 2, characterized in that the second switch operates with power from the first power supply via the first switch.

4. The image forming system according to any one of claims 1 to 3, characterized in that the first load is a second motor that drives a second transport means that receives and transports a sheet transported from the first transport means.

5. The image forming system according to claim 4, characterized in that the second transport means is a rotating body that constitutes the fixing means and transports the sheet.

6. The second device further includes a third conveying means for further conveying the sheet conveyed by the second conveying means, The image forming system according to claim 4 or 5, characterized in that the second load is a third motor that drives the third transport means.

Images