Image forming system and sheet transport 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 technology]

[0002] The image forming apparatus is equipped with an interlock mechanism that cuts off the power supply to the drive source when a maintenance cover that allows a user to access the inside of the image forming apparatus is opened. According to Patent Document 1, it is proposed to cut off the power supply to the load by a relay that turns on and off in conjunction with the opening and closing of the cover. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4124438 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to efficiently develop a plurality of different types of image forming apparatuses, it is possible to use a fixing device developed on the premise that it is connected to a certain type of image transfer device for another type of image transfer device. However, if the height of the discharge port of a certain type of image transfer device is different from the height of the discharge port of another type of image transfer device, this fixing device cannot be connected to the other type of image transfer device. Therefore, a conveying device that relays a sheet between the other type of image transfer device and the fixing device is required. Such a conveying device conveys a sheet carrying an unfixed toner image. If the height of the opening of the communication part that communicates between the conveying device and the fixing device is insufficient, the toner image may come into contact with the edge of the opening and be disturbed. Therefore, the opening is designed to be large.

[0005] A maintenance door (cover) is also required for such a conveying device to remove a jammed sheet. Here, if the opening of the communication part 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 inside the housing of the conveying device through the communication part. This may lead to failure of the load. Here, the conveying device and the fixing device are given as an example, but similar problems arise between multiple adjacent housings. Therefore, the present invention aims to appropriately cut off the supply of power 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 relates to, for example, a first housing including a transfer unit for transferring a toner image onto a sheet; a second housing provided downstream of the first housing in a sheet transport direction and including a transport means for transporting the sheet onto which the unfixed toner image is transferred and discharged from the first housing; a third housing connected to the second housing and including a fixing unit for fixing the toner image on a sheet discharged from the second housing; An image forming system having: The second housing includes: A motor for driving the conveying means; a first door that can be opened to expose an interior of the second housing; a first switch that is provided in a path connecting the motor and a power source that supplies power to the motor, the first switch being switched to a first state in which the power source and the motor are connected when the first door is closed, and being switched to a second state in which the power source and the motor are disconnected when the first door is open; The third housing is a second door that can be opened to expose an interior of the third housing; When the first switch is in the first state, power is supplied. first load and, a second load that is powered independently of the state of the first switch; having The first switch is in the first state. and the second door is closed. In the state, the first door is opened, and the first switch is switched to the second state, first Power supply to the load is cut off However, the power supply to the second load is not interrupted. The present invention provides an image forming system. Effect 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 supply of power to a load provided in the other housing. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 illustrates an image forming system. [Diagram 2] 5A and 5B are diagrams illustrating opening and closing of the maintenance door. [Diagram 3] FIG. 2 is a diagram illustrating an interlock mechanism according to the first embodiment. [Figure 4] FIG. 11 is a diagram illustrating an interlock mechanism according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0010] <Image forming system> As shown in Fig. 1, the image forming system 1 of this embodiment has three devices. The image forming apparatus 100 transfers a toner image onto a sheet P and discharges the sheet P to a conveying apparatus 110. The conveying apparatus 110 is an intermediate apparatus that receives the sheet P carrying an unfixed toner image from the image forming apparatus 100 and passes it on to a 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 onto 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 each provided separately.

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

[0012] Image forming equipment The image forming apparatus 100 will be described in detail. The image forming apparatus 100 is equipped with image forming units PY, PM, PC, and PK. The image forming unit PY forms a yellow toner image. The image forming unit PM forms a magenta toner image. The image forming unit PC forms a cyan toner image. The 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 numbers indicate the colors of the toner. When matters common to the four colors are described, the letters Y, M, C, and K are omitted from the reference numbers.

[0013] The image forming section P includes a photoconductor drum 10, a charger 11, an exposure device 3, a developing device 12, a drum cleaner 13, and the like. The photoconductor 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 photoconductor drum 10. The exposure device 3 irradiates the surface of the photoconductor drum 10 with a laser beam corresponding to an image signal to form an electrostatic latent image corresponding to the image signal. The developing device 12 attaches toner to the electrostatic latent image to form a toner image. The primary transfer device 14 transfers the toner image from the photoconductor drum 10 to the intermediate transfer belt 20. The drum cleaner 13 cleans the toner remaining on the surface of the photoconductor drum 10.

[0014] The intermediate transfer belt 20 is an intermediate transfer body or image carrier that rotates while being tensioned 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 conveys the toner image to a 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 a 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 storages 30 capable of storing a large number of sheets P. A separation belt 31 separates the topmost sheet P from the sheet stack stored in the storage 30 and feeds it to a paper feed roller 32. The paper feed roller 32 conveys the sheet P and delivers it to a conveying roller 33. The conveying roller 33 further conveys the sheet P downstream in the conveying direction of the sheet P and delivers 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 direction or the lateral direction of the sheet P in parallel with the conveying direction of the sheet P. This process may be called skew correction. The plurality of registration rollers 34 convey the sheet P so that the timing at which the toner image arrives at the secondary transfer unit and the timing at which the sheet P arrives at the secondary transfer unit coincide with each other.

[0016] Conveyor belt units 35 and 36 are provided downstream of the secondary transfer portion. The conveyor belt units 35 and 36 convey the sheet P further downstream. Here, the conveyor belt units 35 and 36 may convey the sheet P while adsorbing it with negative pressure. The negative pressure is generated, for example, by adsorbing air. The reason that the sheet P is adsorbed to the conveyor belt units 35 and 36 with negative pressure is to prevent the unfixed toner image on the sheet P from being disturbed even if the sheet P is conveyed at high speed. The conveyor belt unit 36 ​​delivers the sheet P to the conveying device 110.

[0017] ●Transportation equipment The conveyor belt unit 40 of the conveying device 110 conveys the sheet P delivered from the image forming device 100 to the fixing device 120. The conveyor belt unit 40 may also convey the sheet P while adsorbing it. The housing of the conveying 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 opening 42 and the opening 50 face each other and form a communication section 43. That is, the sheet P is conveyed from the conveying device 110 to the fixing device 120 through the communication section 43. Here, an unfixed toner image exists on the sheet P conveyed from the conveying device 110 to the fixing device 120. The opening area of ​​the opening 42 is designed to be large enough 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 fixing unit 51. The fixing unit 51 has a heating belt 53. The heating belt 53 is stretched by a heating roller 52, a tension roller 54, and a fixing roller 55, and rotates. 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 portion. The fixing roller 55 and the pressure roller 57 rotate while holding the heating belt 53 between them. The fixing nip portion applies heat and pressure to the sheet P to fix the toner image onto the sheet P.

[0019] In the single-sided printing mode, the sheet P is discharged to the outside of the fixing device 120 by the discharge rollers 58. An output tray or a post-processing device may be connected to the outside of the fixing device 120. The post-processing device performs post-processing (e.g., bookbinding, binding, punching) on ​​the sheet P.

[0020] In the double-sided printing mode, the sheet P with the toner image formed on the first surface is returned to the image forming apparatus 100 via the conveying device 110. That is, the reversing roller 59 pulls in the sheet P and delivers the sheet P to the conveying roller 60, thereby reversing the sheet P (switchback reversal). The conveying roller 60 conveys the sheet P and delivers it to the conveying roller 41 of the conveying device 110. The conveying roller 41 further conveys the sheet P and delivers it to the conveying roller 37 of the image forming apparatus 100. The conveying roller 37 conveys the sheet P and delivers it to the conveying roller 33. The conveying roller 33 delivers the sheet P to the registration roller 34. The registration roller 34 conveys the sheet P again to the secondary transfer section. The secondary transfer section transfers the toner image to the second surface of the sheet P. Thereafter, the sheet P is discharged to the outside of the fixing device 120 via the conveying device 110 and the fixing device 120.

[0021] ●Appearance of image forming device 2A shows a state in which covers 201 to 204 are closed. Covers 201 and 202 are maintenance doors that form part of a housing 200 of image forming apparatus 100. Covers 201 and 202 are opened by a user when a jam of sheet P occurs. When sheet P is removed, covers 201 and 202 are closed.

[0022] The cover 203 forms a part of a housing 210 of the conveying device 110. When a sheet P jams in the conveying device 110, a user opens the cover 203 and removes the sheet P.

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

[0024] FIG. 2B shows a state in which the covers 203 and 204 are open. FIG. 2C shows a state in which the cover 203 is open but the cover 204 is closed. As shown in FIG. 2B and FIG. 2C, the housing 210 is provided with an opening 42. When the cover 203 is opened, a user can access some of the loads of the fixing device 120 (e.g., the heating belt 53 stretched around 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 heating belt 53 through the opening 42, the fixing device 51 including the heating belt 53 may break down. Therefore, when the cover 203 is opened, the supply of power should be cut off not only to the loads provided inside the conveying device 110 but also to some of the loads of the fixing device 120. The part of the loads of the fixing device 120 includes at least the fixing device 51. In other words, the supply of power to the motor that drives the heating belt 53 is cut off.

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

[0026] The relay unit 304 converts +12V_M output from the 12V power supply 302 into 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 a switch SW1. The switch SW 1 The other end of the switch SW2 is connected to one end of the switch SW2. The other end of the switch SW2 applies +12VIL_M to one end of the coil of the relay RL1. The switch SW1 is an interlock switch that turns on and off in conjunction with the opening and closing of the cover 201. The switch SW2 is an interlock switch that turns on and off in conjunction with the opening and closing of the cover 202. Note that the switches SW1, SW2 and the relay RL1 only need to be able to cut off the power supply to the load when the covers 201 and 202 are opened. In other words, when either the cover 201 or the cover 202 is opened, the two contacts of the relay RL1 open to cut off the supply of the DC voltage +24VIL_M. When both the cover 201 and the cover 202 are closed, the switches SW1 and SW2 are both turned on, the two contacts of the relay RL1 close, and the DC voltage +24VIL_M can be supplied.

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

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

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

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

[0031] The controller 305 controls the power supply to the load by outputting a control signal to the bases of the transistors Tr1 and Tr2. When the controller 305 is started, the controller 305 turns on the transistors Tr1 and Tr2 to supply power to the motors M1 to M8, the exposure unit 3, and the high-voltage power supply 2. The controller 305 executes image formation by outputting operation command signals to the exposure unit 3, the high-voltage power supply 2, and the motors M1 to M8. The controller 305 executes serial communication with the controller 315 of the conveying device 110 and the controller 325 of the fixing device 120, and controls the conveying device 110 and the fixing device 120.

[0032] ●Interlock mechanism for transport equipment The conveying device 110 is connected to a commercial AC power source 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 the AC voltage to a 12V power source 312 and a 24V power source 313. The 12V power source 312 is a power source circuit that converts the AC voltage to a DC voltage +12V. The 24V power source 313 is a power source circuit that converts the AC voltage to a DC voltage +24V. Hereinafter, the DC voltage +12V is expressed as +12V_D in the section upstream of the switch SW3, and as +12VIL_D in the section downstream of the switch SW3. +12V_D and +12VIL_D may be understood to indicate a power supply system for supplying +12V. Similarly, the DC voltage +24V is expressed as +24V_D in the section upstream of the relay RL3, and as +24VIL_D in the section downstream of the relay RL3. +24V_D and +24VIL_D may be understood to represent a power supply system for supplying +24 V. The DC voltages +12V_D and +24V_D are input to a relay unit 314.

[0033] The relay unit 314 converts the DC voltage +12V_D output from the 12V power supply 312 into 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 the switch SW3. The switch SW3 is an interlock switch that turns off and on in conjunction with the opening and closing of the cover 203. The other end of the switch SW3 supplies +12VIL_D to one end of the coil of the relay RL3. In this way, +12VIL_D can be supplied when the cover 204 is closed, and can be supplied when the cover 204 is closed. Open If this is the case, the supply of DC voltage is prohibited (cut off).

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

[0035] The emitter of the transistor Tr3 is grounded. The base of the transistor Tr3 is connected to the controller 315. The controller 315 controls the supply of +24VIL_D to the load by outputting a control signal to the base of the transistor Tr3. For example, when a start request is input from the controller 305, the controller 315 turns on the transistor Tr3 to start the motor M. 1 It supplies +24VIL_D to M1, M12, etc. When cover 203 is opened, +24VIL_D is cut off by switch SW3 and relay RL3.

[0036] Interlock mechanism of the fixing unit The fixing device 120 is connected to a commercial AC power source 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 a 12V power source 322, a 24V power source 323, and an upstream contact of a relay RL6. The 12V power source 322 is a power source circuit that converts the AC voltage to a DC voltage of +12V. The 24V power source 323 is a power source circuit that converts the AC voltage to a DC voltage of +24V. Hereinafter, the DC voltage +12V is represented as +12V_F in the section upstream of the switch SW4, and as +12VIL_F in the section downstream of the switch SW4. +12V_F and +12VIL_F may be understood to indicate a power supply system for supplying +12V. Similarly, the DC voltage +24V is expressed as +24V_F in the section upstream of the relay RL4, and as +24VIL_F in the section downstream of the relay RL4. +24V_F and +24VIL_F may be understood to indicate a power supply system for supplying +24V. The DC voltages +12V_F and +24V_F are input to a relay unit 324. A heater 56 is connected to the downstream contact of the relay RL5 via a drive circuit 326.

[0037] The relay unit 324 converts +12V_F output from the 12V power supply 322 into 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. The switch SW4 is an interlock switch that turns off and on in conjunction with the opening and closing of the cover 204. The other end of the switch SW4 is connected to one end of the coil of the relay RL4 and one end of the coil of the relay RL5. In other words, +12VIL_F is used as the operating voltage for the coil of the relay RL4 and the coil of the relay RL5. When the cover 204 is opened, the supply of +12VIL_F is cut off, so that both relays RL4 and RL5 are turned off (cut off state).

[0038] The other end of the coil of the relay RL4 is connected to the collector of the transistor Tr4. The other end of the coil of the relay RL5 is connected to the collector of the transistor Tr5. The emitters of the transistors Tr4 and Tr5 are grounded. The bases of the transistors Tr4 and Tr5 are connected to the 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 discharge roller 58. Motor M23 drives reversing roller 59. Motor M24 drives conveying roller 60. Here, motor M21 is a motor that drives fixing unit 51. The operating voltage of motor M21 is +24VIL_D supplied from conveying device 110.

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

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

[0042] When the cover 203 of the conveying device 110 is opened, the switch SW3 is turned off and the supply of +12VIL_D is cut off. The coil of the relay RL3 loses the operating voltage of +12VIL_D, and the relay RL3 is turned off. The motors M11 and M12 connected to the downstream contact of the relay RL3 and the motor M21 of the fixing device 120 lose the operating voltage of +24VIL_D and stop.

[0043] When the cover 204 of the fixing device 120 is opened, the switch SW4 is turned off. As a result, the relays RL4 and RL5 lose the operating voltage of +12VIL_F, and the relays RL4 and RL5 are turned off. The motors M22 to M24 connected to the downstream contact of the relay RL4 lose the operating voltage of +24VIL_F. The drive circuit 326 and the heater 56 connected to the downstream contact of the relay RL5 also lose the AC voltage. Note that even if the cover 204 is opened, the motor M21 does not lose the operating voltage.

[0044] According to the first embodiment, 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 supply of power 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 the failure of some of the loads provided in the fixing device 120.

[0045] [Example 2] Fig. 4 shows an interlock mechanism of the embodiment 2. As can be seen by comparing with Fig. 3, the parts surrounded by the dashed line in Fig. 4 are the changed parts. In the embodiment 2, the description of the parts common to the embodiment 1 will be omitted.

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

[0047] When the cover 203 of the transport device 110 is opened, the coil of the relay RL6 loses the operating voltage +24VIL_D. This causes the relay RL6 to cut off the supply of +24VIL_F, so that the motor M21 loses the operating voltage +24VIL_F.

[0048] In the embodiment 1, the operating voltage of the motor M21 was +24VIL_D, but in the embodiment 2, the operating voltage is changed to +24VIL_F. However, the embodiment 1 and the embodiment 2 have in common that when +24VIL_D is cut off, the motor M21 loses the operating voltage.

[0049] In the first embodiment, even if the cover 204 of the fixing device 120 is opened, the motor M21 does not lose its operating voltage. However, in the second embodiment, when the cover 204 is opened, the motor M21 also loses its operating voltage. In the first embodiment, in order to reduce access to the heating belt 53 of the fixing device 51 when the cover 204 of the fixing device 120 is opened, some kind of protective member may be required for the fixing device 51. In the second embodiment, there is an advantage in that such a protective member can be omitted.

[0050] <Other> In the above embodiment, 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, and may be a heater (e.g., heater 56). That is, 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 the heater and the motor of the fixing device 120 may be cut off. For example, according to FIG. 3, the power is supplied to the heater 56 through the relay RL5. Therefore, when the cover 203 of the conveying device 110 is opened, the relay RL5 may be switched from on to off. To achieve this, when the cover 203 of the conveying device 110 is opened, the supply of the operating voltage +12VIL_F applied to one end of the coil of the relay RL5 may be stopped. For example, +12VIL_D or +24VIL_D generated by the transport device 110 may be supplied as the operating voltage of the coil of the relay RL5 instead of +12VIL_F. When +24VIL_D is used, a resistor circuit (voltage divider circuit) or regulator that steps down +24VIL_D to +12 V may be employed. Note that a power line is added to supply +12VIL_D or +24VIL_D from the transport device 110 to one end of the coil of the relay RL5.

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

[0052] <Technical ideas derived from examples> [Point 1, 16] As shown in FIG. 1, the conveying device 110 is an example of a first device having a first housing, which is provided downstream of the image forming device 100 in the sheet conveying direction. The fixing device 120 is an example of a second device having a second housing connectable to the first housing and receiving a sheet from the first device. The 12V power source 312 and the 24V power source 312 are examples of a first power source that converts an AC voltage supplied from an AC power source into a DC voltage. The motors M11 and M12 are examples of a first load provided inside the first housing. The cover 203 is an example of a first door that forms a part of the first housing and can be opened and closed. The switch SW3 is an example of a first interlock switch that is switched 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 a DC voltage (e.g., +24V) generated by the first power source to the first load. The relay RL3 is an example of a first switch element that switches between a supply enable state and a supply disable state of the DC voltage by the first supply system. The first switch element may be configured to switch between the supply-enabled state and the supply-prohibited state in conjunction with at least the on / off of the first interlock switch. The fixing roller 55, the heating belt 53, and the motor M21 are examples of the second load provided inside the second housing. As shown in FIG. 2(C) and other figures, the second load is disposed 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 portion between the first housing and the second housing. As shown in FIGS. 3 and 4, the supply and cut-off of the operating voltage required for the second load to operate is switched in conjunction with the on / off of the first switch element provided in the first device. In other words, when the first door is opened, the operating voltage required for the second load to operate is cut off. In this way, when the cover of one of the two adjacent housings is opened, it is possible to appropriately cut off the supply of power to the load provided in the other housing.

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

[0054] [Point 3] The first switch element may include a switch device (e.g., a relay RL3) that operates with a DC voltage supplied from the first power source. The switch device may be switched from a supply enabled state to a supply prohibited state by cutting off the DC voltage (e.g., +12VIL_D) supplied from the first power source by the first interlock switch.

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

[0056] [Point 7] The first power supply may include 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 is configured to supply the first DC voltage to the first supply system. The first switch element (e.g., relay RL3) is configured to operate by the second DC voltage supplied via the first interlock switch. When the supply of the second DC voltage to the first switch element is cut off by the first interlock switch, the supply of the first DC voltage via the first supply system is cut off by the first switch element.

[0057] [Point 8] The 12V power supply 322 and the 24V power supply of the fixing device 120 are an example of a second power supply that converts an AC voltage supplied from an AC power supply into a DC voltage (e.g., +24V). +24VIL_F may be understood as a second supply system that supplies a DC voltage generated by the second power supply to a second load. As shown in FIG. 4, the relay RL6 is an example of a second switch element that switches between a supply enable state and a supply disable state of a DC voltage by the second supply system. The second switch element is configured to switch between the supply enable state and the supply disable state in conjunction with at least the on / off of the first switch element. In this way, even in a case 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] [Point 9] The second switch element may include a switch device (e.g., a relay RL6) that operates with a DC voltage supplied from the second power source. The switch device may be switched from on to off when the DC voltage supplied from the first power source is cut off by the first interlock switch. As a result, the switch device may cut off the supply of DC voltage from the second supply system to the second load.

[0059] [Points 10-12] The switch device may be a relay (e.g., relay RL6) having two contacts and a coil for opening and closing the two contacts. A DC voltage supplied from the first power source may be applied to one end of the coil. That is, when the DC voltage supplied from the first power source is cut off by the interlock mechanism of the first device, the relay may be turned off. The switch may further include 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 switch device may be a semiconductor switch (e.g., FET).

[0060] [Point 13] The second device (e.g., fixing device 120) may have a second power source connected to an AC power source, and a second load (e.g., motor M21) and a third load (e.g., motors M22 to M24) provided inside the second housing. The second device may have a second door (e.g., cover 204) that forms a part of the second housing and that can be opened and closed, and a second interlock switch (e.g., switch SW4) that is switched 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 source to the third load. The relay RL4 is an example of a second switch element that switches between a supplyable state and a supply-prohibited state of power by the second supply system. The second switch element may be configured to switch between the supplyable state and the supply-prohibited state in conjunction with at least the on and off of the second interlock switch. The second load switches between supply and cut-off of an operating voltage required for the second load (e.g., motor M21) to operate in conjunction with the on and off of a first switch element provided in the first device. In this way, the first device and the second device may have independent interlock mechanisms, while the second load of the second device may have its operating voltage cut off by the interlock mechanism of the first device.

[0061] [Point 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 the second supply system (+24V_F, +24VIL_F) and configured to supply the third DC voltage to the second supply system. The second switch element (e.g., relay RL6) is configured to operate by the second DC voltage supplied via the first interlock switch (e.g., switch SW3). When the supply of the second DC voltage (e.g., +24VIL_D) to the second switch element is cut off by the first interlock switch, the supply of the third DC voltage via the second supply system is cut off by the second switch element.

[0062] [Point 15] 4, the operating voltage required for operating the second load may be a third DC voltage via the second supply system. The supply of the third DC voltage to the second load may be cut off by cutting off the supply of the third DC voltage to the second switch element (e.g., relay RL6) by a second interlock switch (e.g., switch SW4). In this way, the supply of the operating voltage to the second load may be cut off independently by two interlock mechanisms.

[0063] [Point 17] 1, the first device may include a transport device 110. The second device may include a fixing device 120 that fixes the toner image transferred to the sheet onto the sheet. The fixing device 120 includes a second load. The first device and the second device may be two adjacent post-processing devices. The first device and the second device may be two adjacent sheet feeding devices that feed sheets to the image forming apparatus 100.

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

[0065] 1: image forming system, 100: image forming apparatus, 110: conveying apparatus, 120: fixing apparatus

Claims

1. a first housing including a transfer unit for transferring a toner image onto a sheet; a second housing provided downstream of the first housing in a sheet transport direction and including a transport means for transporting the sheet onto which the unfixed toner image is transferred and discharged from the first housing; a third housing connected to the second housing and including a fixing unit for fixing the toner image on a sheet discharged from the second housing; An image forming system having: The second housing includes: A motor for driving the conveying means; a first door that can be opened to expose an interior of the second housing; a first switch that is provided in a path connecting the motor and a power source that supplies power to the motor, the first switch being switched to a first state in which the power source and the motor are connected when the first door is closed, and being switched to a second state in which the power source and the motor are disconnected when the first door is open; The third housing is a second door that can be opened to expose an interior of the third housing; a first load to which power is supplied when the first switch is in the first state; a second load that is powered independently of the state of the first switch; An image forming system characterized in that, when the first switch is in the first state and the second door is closed, the first door is opened and the first switch switches to the second state, thereby cutting off the power supply to the first load but not cutting off the power supply to the second load.

2. The power source includes: a first power supply circuit generating a first DC voltage; a second power supply circuit generating a second DC voltage; the first power supply circuit is connected to the first switch; 2. The image forming system according to claim 1, wherein when the first switch is in the first state, the first switch switches to the second state when the supply of the second DC voltage to the first switch is cut off.

3. 3. The image forming system according to claim 1, wherein the first load is supplied with power from the power source via the first switch.

4. The third housing is a second power source supplying power to the first load; a second switch that is provided in a path that connects the second power source and the first load, and that is switched to a third state in which the second power source and the first load are connected when the first switch is in the first state, and is switched to a fourth state in which the second power source and the first load are disconnected when the first switch is in the second state; having 3. The image forming system according to claim 1, wherein the second switch is operated by power from the power source via the first switch.

5. the third housing has a rotating body that transports a sheet discharged from the second housing, 5. The image forming system according to claim 1, wherein the first load is a second motor that drives the rotating body.

6. 6. The image forming system according to claim 5, wherein the rotating body constitutes the fixing means.

7. The fixing means is A heater and a third switch that cuts off the power supply to the heater when the first door is opened; 7. The image forming system according to claim 1, further comprising:

8. An image forming system described in any one of claims 1 to 7, characterized in that the second load is a third motor that drives a roller that transports the sheet downstream of the fixing means in the sheet transport direction.

9. a first housing including a conveying means for conveying a sheet; a second housing connected to the first housing and including a receiving means for receiving a sheet discharged from the first housing; A sheet transport system comprising: The first housing includes: A first load provided inside the first housing; and a first door that can be opened to expose an interior of the first housing; a first switch that is provided in a path connecting the first load and a first power source that supplies power to the first load, the first switch being switched to a first state in which the first power source and the first load are connected when the first door is closed and to a second state in which the first power source and the first load are disconnected when the first door is open; The second housing includes: a second power source connected to the AC power source; A second load and a third load provided inside the second housing; a second door that can be opened to expose an interior of the second housing; a second switch that is provided in a path that connects the second power source and the third load, and that switches between a third state in which the second power source and the third load are connected and a fourth state in which the second power source and the third load are not connected; A sheet conveying system characterized in that, when the first switch is in the first state and the second door is closed, the first door is opened and the first switch switches to the second state, thereby cutting off the power supply to the second load, but not cutting off the power supply to the third load.

10. The first power source is a first power supply circuit generating a first DC voltage; a second power supply circuit for generating a second DC voltage; 10. The sheet conveying system of claim 9, wherein the first switch is operated by the second DC voltage, and when the supply of the second DC voltage to the first switch is cut off, the supply of the first DC voltage via the first switch is cut off.

11. 11. The sheet conveying system according to claim 9, wherein the second load is supplied with power from the first power source via the first switch.

12. a third switch that is provided in a path that connects the second power source and the second load, and that switches between a fifth state in which the second power source and the second load are connected and a sixth state in which the second power source and the second load are not connected; The sheet conveying system of claim 10, wherein the third switch is operated by the first DC voltage, and when the third switch is in the fifth state, the first door is opened and the first switch switches to the second state, thereby switching the third switch to the sixth state, and cutting off the supply of power from the second power source to the second load.

13. The second power source: a third power supply circuit generating a third DC voltage; a fourth power supply circuit that generates a fourth DC voltage; the second load is powered by the third DC voltage via the third switch; the second switch is operated by the fourth DC voltage; 13. The sheet transport system according to claim 12, wherein when the supply of the first DC voltage to the third switch is cut off, the supply of the third DC voltage to the second load is cut off.

14. The second load is a first driving means that drives a first conveying means that conveys the sheet received from the first housing, 14. The sheet transport system according to claim 9, wherein the third load is a second driving means for driving a second transporting means for further transporting the sheet transported by the first transporting means.

Images