JP2021131510A - Image forming apparatus - Google Patents

Abstract

To provide a second attachment part to which a second driving unit can be attached so as to supply a driving force to a drive transmission unit that can drive a rotating body only with a driving force from a first driving unit also from the second driving unit.SOLUTION: An image forming apparatus 10 comprises: a rotating body 201 that conveys a sheet; a drive transmission unit 205 that transmits a driving force to the rotating body; a first driving unit 206 that supplies a first driving force to the drive transmission unit; a first attachment part 506 to which the first driving unit is attached; a second attachment part 507 to which a second driving unit 207 can be attached; and a control unit 200 that controls the first driving unit. When the second driving unit is not attached to the second attachment part, the first driving force is supplied to the drive transmission unit only by the first driving unit. When the second driving unit is attached to the second attachment part, the control unit controls the first driving unit and the second driving unit, and the first driving unit and the second driving unit supply the second driving force to the drive transmission unit.SELECTED DRAWING: Figure 2

Description

The present invention relates to an image forming apparatus having a drive transmission unit that transmits a driving force to a rotating body by a plurality of drive units or a single drive unit.

The electrophotographic image forming apparatus includes a fixing unit that heats and pressurizes the recording medium on which the toner image is transferred to fix the toner image on the recording medium. In recent years, high-end models of image forming apparatus have been capable of forming images on various recording media (thin paper, thick paper, coated paper, glossy paper, film, etc.), improved glossiness of formed images, and high productivity. Is required. In order to achieve these, the fixing portion pressurizes the recording medium at a higher pressure at the nip portion, so that the required load torque is increased.

On the other hand, the lower model of the image forming apparatus is limited to the use of plain paper or thin paper without using thick paper or coated paper. Compared to the higher model, the lower model does not require much pressure at the nip part, but higher cost performance is required due to the longer life and lower cost of the fixing part. As a result, such a low-cost fixing unit is designed so that it can be driven with a smaller driving torque as compared with a higher-end model (Patent Documents 1 and 2).

JP-A-2017-146396 Japanese Unexamined Patent Publication No. 2012-145710

However, if the high-end model and the low-end model are designed separately, the sheet metal of the fixing part and the drive part will be unique to each model, and the types of parts will increase. As a result, the unit price of parts increases due to the decrease in the production quantity per part, the mold cost and the management cost increase due to the increase in the types of molds, and the production cost of the image forming apparatus increases. On the other hand, when designing a common component that can be used in common for a high-end model and a low-end model, it is necessary to design the common component according to the required specifications of the high-end model. High-strength sheet metal and high-torque drive units used in higher-end models are more expensive than those used in lower-end models. Therefore, common parts are over-engineered and expensive for lower-end models. Therefore, the total manufacturing cost of the upper model and the lower model may increase due to the standardization of the parts of the upper model and the lower model.

Therefore, in the present invention, the second drive unit is provided so as to supply the drive force from the second drive unit to the drive transmission unit that can drive the rotating body only by the drive force from the first drive unit. Provided is an image forming apparatus that can be attached to the attachment portion of the above.

The image forming apparatus according to an embodiment of the present invention is
A rotating body that conveys the sheet and
A drive transmission unit that transmits the driving force to the rotating body,
A first drive unit that supplies a first drive force to the drive transmission unit,
The first mounting part to which the first driving part is mounted and
A second mounting part to which the second driving part can be mounted,
A control unit that controls the first drive unit and
With
When the second drive unit is not attached to the second mounting unit, the first drive force is supplied to the drive transmission unit only by the first drive unit.
When the second drive unit is attached to the second mounting unit, the control unit controls the first drive unit and the second drive unit, and the first drive unit and the first drive unit. The second drive unit is characterized in that a second drive force is supplied to the drive transmission unit.

According to the present invention, the second drive unit is provided so as to supply the drive force from the second drive unit to the drive transmission unit that can drive the rotating body only by the drive force from the first drive unit. It can be attached to the attachment part of.

Sectional view of image forming apparatus. Block diagram of the drive control system. The figure which shows the sheet metal. The flow chart which shows the drive control of a fixing part. Timing chart of the rotation speed of the drive unit and the control signal in the high-end model. Timing chart of the rotation speed of the drive unit and the control signal in the lower model.

(Image forming device)
FIG. 1 is a cross-sectional view of the image forming apparatus 10. The image forming apparatus 10 is a tandem type color image forming apparatus in which four image forming portions 100Y, 100M, 100C and 100K are arranged side by side. However, the image forming apparatus 10 is not limited to the color image forming apparatus for forming a color image, and may be a monochrome image forming apparatus for forming a monochrome image. The image forming apparatus 10 may be a copier, a color LED printer, an MFP (multifunction printer), or a facsimile apparatus.

The image forming apparatus 10 includes image forming portions 100Y, 100M, 100C and 100K of each color of yellow (Y), magenta (M), cyan (C) and black (K). In each of the image forming portions 100Y, 100M, 100C and 100K, the photosensitive drums 101Y, 101M, 101C and 101K which are image carriers rotate in the direction indicated by the arrow R in FIG. The surfaces of the photosensitive drums 101Y, 101M, 101C and 101K are charged to a uniform potential by the primary chargers 102Y, 102M, 102C and 102K. The laser scanning units 103Y, 103M, 103C and 103K using a semiconductor laser as a light source irradiate the laser beam L to form an electrostatic latent image based on image data on the surfaces of the photosensitive drums 101Y, 101M, 101C and 101K.

The electrostatic latent image on the surface of the photosensitive drums 101Y, 101M, 101C and 101K is developed by the developing devices 104Y, 104M, 104C and 104K to become a toner image. The toner images of each color are shown in the intermediate transfer belt 107 in the primary transfer section where the primary transfer rollers 105Y, 105M, 105C and 105K to which high pressure is applied and the photosensitive drums 101Y, 101M, 101C and 101K are rubbed via the intermediate transfer belt 107. Is sequentially transferred to. The toner images of each color superposed on the intermediate transfer belt 107 are conveyed to the secondary transfer unit ST.

The feeding cassette 111 stores a recording medium (hereinafter, referred to as a sheet) P. The sheet P is a recording material on which an image is formed by the image forming apparatus 10. Sheet P includes plain paper, thin paper, thick paper, special paper such as glossy paper, coated paper, plastic film for overhead projectors, cloth, and other materials, as well as envelopes and index sheets. Those having an arbitrary shape are included. The sheet P is transported from the feed cassette 111 to the secondary transfer section ST by a plurality of roller pairs in the feed transport section 130. In the secondary transfer unit ST, a high voltage is applied to the secondary transfer roller 108. The four-color toner images superimposed on the intermediate transfer belt 107 are collectively transferred to the sheet P by the secondary transfer unit ST.

The drum cleaners 106Y, 106M, 106C and 106K remove the toner remaining on the surfaces of the photosensitive drums 101Y, 101M, 101C and 101K after the primary transfer. The belt cleaner 112 removes the toner remaining on the surface of the intermediate transfer belt 107 after the secondary transfer.

The sheet P on which the toner images of four colors are collectively transferred by the secondary transfer unit ST is conveyed to the fixing unit 109. The fixing portion 109 has a first rotating body 201 and a second rotating body 202. In this embodiment, the first rotating body 201 is a pressure roller arranged on the lower side, and the second rotating body 202 is a heating roller arranged on the upper side. The first rotating body 201 and the second rotating body 202 are pressed against each other to form a fixing nip FN between the first rotating body 201 and the second rotating body 202. The sheet P is heated and pressurized by the fixing nip FN, and the toner image is heat-fixed to the sheet P. The sheet P on which the image is formed is discharged to the discharge tray 110 by the discharge transport unit 131.

(Drive control system)
FIG. 2 is a block diagram of the drive control system 20. The drive control system 20 has a fixing unit 109. There are a plurality of types of fixing portions 109 having different required load torques. The plurality of types of fixing units 109 are exclusively selected and incorporated into the drive control system 20. When the fixing unit 109 having a small required load torque is incorporated in the drive control system 20, the drive control system 20 includes a heater drive circuit 242, a first drive unit 206, and a control unit 200. When the fixing unit 109 having a large required load torque is incorporated in the drive control system 20, the drive control system 20 has a second drive unit 207 in addition to the heater drive circuit 242, the first drive unit 206, and the control unit 200. .. That is, the second drive unit 207 may or may not be incorporated in the drive control system 20 according to the required load torque of the fixing unit 109.

The first drive unit 206 and the second drive unit 207 each include a motor. The cost of a high-power motor capable of outputting high torque is higher than that of a low-power motor. Therefore, there is an assist drive technology as a technology for rotating one load by using a plurality of low output motors having a low unit price per wattage. If the assist drive technology is used, the corresponding design can be made by changing the number of motors according to the size of the load. In this embodiment, the number of drive units is increased or decreased according to the required load torque of the fixing unit 109. That is, when the required load torque of the fixing unit 109 is small, only the first driving unit 206 is incorporated into the image forming apparatus 10 at the time of producing the image forming apparatus 10. When the required load torque of the fixing unit 109 is large, both the first drive unit 206 and the second drive unit 207 are incorporated into the image forming device 10 at the time of production of the image forming device 10.

The control unit 200 has a CPU 250 and a memory (storage unit) 251. The control unit 200 controls the drive of the fixing unit 109 and executes the overall sequence control of the image forming apparatus 10. The memory 251 stores set values such as control parameters required when the CPU 250 executes drive control and sequence control.

The first rotating body 201 is configured to rotate in synchronization with the output shaft 204 of the drive gear 205. The second rotating body 202 rotates in accordance with the rotation of the first rotating body 201. The second rotating body 202 includes a temperature sensor (temperature detecting means) 241 that detects the temperature of the second rotating body 202 and a heater (heating means) that generates heat necessary for fixing the toner image on the sheet P. 240 and are built-in. In this embodiment, the temperature sensor 241 and the heater 240 are provided on the second rotating body 202, but the temperature sensor 241 and the heater 240 may be provided on the first rotating body 201. A temperature sensor 241 and / or a heater 240 may be provided on at least one of the first rotating body 201 and the second rotating body 202.

The heater 240 is electrically connected to the heater drive circuit 242. The heater drive circuit 242 changes the amount of heat generated by the heater 240 by changing the current flowing from the heater power supply VH to the heater 240. The heater drive circuit 242 and the temperature sensor 241 are electrically connected to the CPU 250. The CPU 250 receives the temperature detection signal Sigma_Tmp from the temperature sensor 241 and outputs the control signal Sigma_Htr that drives the heater drive circuit 242 based on the temperature detection signal Sigma_Tmp. The CPU 250 controls the temperature of the first rotating body 201 and the second rotating body 202 by changing the control signal Sigma_Htr based on the temperature detection signal Sigma_Tmp to change the current flowing through the heater 240.

In this embodiment, the first rotating body 201 and the second rotating body 202 are configured to rotate only in the direction in which the sheet P is conveyed in order to fix the toner image on the sheet P. Therefore, the drive gear 205 rotates in only one direction. A gear box (not shown) is provided on the main body (not shown) or the fixing portion 109 of the image forming apparatus 10. The gearbox (not shown) rotatably supports the drive gear 205. The gear box (not shown) has a sheet metal (support member) 500.

FIG. 3 is a diagram showing the sheet metal 500. The sheet metal 500 is provided with a plurality of drive mounting portions, that is, a first mounting portion 506 and a second mounting portion 507. The first drive unit 206 can be attached to the first attachment unit 506. A second drive unit 207 can be attached to the second attachment unit 507. In this embodiment, the first mounting portion 506 and the second mounting portion 507 are circular in-row holes. FIG. 3 is a diagram showing the sheet metal 500 as seen from the side of the first drive unit 206 and the second drive unit 207. In FIG. 3, the portion of the drive gear 205 shown by the dotted line is hidden behind the sheet metal 500 and represents a portion that cannot be seen. The portion of the drive gear 205 shown by the solid line represents the outer peripheral portion of the drive gear 205 that can be visually recognized through the first mounting portion 506 and the second mounting portion 507. The outer peripheral portion of the drive gear 205 is a meshing portion capable of meshing with the first gear 216 (FIG. 2) of the first drive unit 206 and the second gear 226 (FIG. 2) of the second drive unit 207.

As shown in FIG. 2, the first driving unit 206 has a first rotating shaft 215, a first gear 216 provided on the first rotating shaft 215, and a first convex portion 217. .. The first convex portion 217 is a circular in-row convex portion centered on the first rotation axis 215. The second driving unit 207 has a second rotating shaft 225, a second gear 226 provided on the second rotating shaft 225, and a second convex portion 227. The second convex portion 227 is a circular in-row convex portion centered on the second rotation axis 225.

When the fixing unit 109 having a small required load torque is incorporated in the drive control system 20, only the first drive unit 206 as a single drive unit is attached to the sheet metal 500 without using the second drive unit 207. The first convex portion 217 of the first drive portion 206 is inserted into the first mounting portion 506 and fitted to the first mounting portion 506, so that the first gear 216 meshes with the drive gear 205. One drive unit 206 is positioned with respect to the sheet metal 500. If necessary, the first drive unit 206 is fixed to the sheet metal 500 by screws (fixing means). The first drive unit 206 supplies a driving force to the drive gear 205 by the first gear 216. The drive gear 205 as the drive transmission unit transmits the driving force from the first drive unit 206 to the first rotating body 201.

When the fixing unit 109 having a large required load torque is incorporated in the drive control system 20, both the first drive unit 206 and the second drive unit 207 as the plurality of drive units are attached to the sheet metal 500. The second convex portion 227 of the second drive portion 207 is inserted into the second mounting portion 507 and fitted into the second mounting portion 507, so that the second gear 226 meshes with the drive gear 205. The second drive unit 207 is positioned with respect to the sheet metal 500. If necessary, the second drive unit 207 is fixed to the sheet metal 500 by screws (fixing means). The driving force of the first driving unit 206 and the second driving unit 207 supply the driving force to the driving gear 205 by the first gear 216 and the second gear 226, respectively. The drive gear 205 as the drive transmission unit transmits the drive force from the first drive unit 206 and the drive force from the second drive unit 207 to the first rotating body 201.

The first mounting portion 506 and the second mounting portion 507 are both the first gear 216 and the second gear 226 when the first driving portion 206 and the second driving portion 207 are mounted on the sheet metal 500. Is provided at an appropriate position on the sheet metal 500 so that the can mesh with the drive gear 205. If both the first gear 216 and the second gear 226 can mesh with the drive gear 205 and transmit torque to the drive gear 205, the first mounting portion 506 and the second mounting portion 507 can be placed on the sheet metal 500. It may be provided at the position of. By providing the first mounting portion 506 and the second mounting portion 507 on the sheet metal 500 in this way, for example, only one of the first driving portion 206 and the second driving portion 207 is mounted on the sheet metal 500. It becomes possible to drive the drive gear 205.

In this embodiment, the first drive unit 206 and the second drive unit 207 are DC motors (DC motors). The first drive unit 206 includes a first H-bridge circuit 214, a first coil 210, and a first rotor 211. The first rotor 211 is connected to the first rotating shaft 215. When a current flows from the first power supply VM1 to the first coil 210 via the first H-bridge circuit 214, the first rotor 211 rotates and the first rotating shaft 215 rotates. Similarly, the second drive unit 207 has a second H-bridge circuit 224, a second coil 220 and a second rotor 221. The second rotor 221 is connected to the second rotating shaft 225. As a current flows from the second power supply VM2 to the second coil 220 via the second H-bridge circuit 224, the second rotor 221 rotates and the second rotating shaft 225 rotates. The first drive unit 206 and the second drive unit 207 may be a two-phase or three-phase brushless motor. The first drive unit 206 and the second drive unit 207 may be motors of the same type.

The first drive unit 206 has a first speed sensor (rotational speed detecting means) 212 that detects the rotational speed of the first rotor 211. Similarly, the second drive unit 207 has a second speed sensor (rotational speed detecting means) 222 that detects the rotational speed of the second rotor 221. The first speed sensor 212 and the second speed sensor 222 are, for example, encoders, Hall elements, or frequency generators that generate FG signals.

The CPU 250 receives the first detection signal Sigma_ω1 as a detection result from the first speed sensor 212, generates the first control signal Sigma_D1 based on the first detection signal Sigma_ω1, and generates the first control signal Sigma_D1. Output to the first H-bridge circuit 214. The CPU 250 executes speed control of the first drive unit 206 by controlling the first H-bridge circuit 214 by the first control signal Sigma_D1 generated based on the first detection signal Sigma_ω1. The CPU 250 receives the second detection signal Sig_ω2 from the second speed sensor 222. However, the CPU 250 generates a second control signal Sigma_D2 based on the first detection signal Sigma_ω1 from the first speed sensor 212, and outputs the second control signal Sigma_D2 to the second H-bridge circuit 224. The reason will be described later. The CPU 250 executes speed control of the second drive unit 207 by controlling the second H-bridge circuit 224 by the second control signal Sigma_D2.

The higher-end model (first device) of the image forming apparatus 10 is provided with a fixing portion 109 having a large required load torque. The high-end model of the image forming apparatus 10 has, for example, multi-media compatibility (correspondence to thin paper, thick paper and coated paper), high image quality, gloss improvement and high productivity. The lower model (second device) of the image forming apparatus 10 is provided with a fixing portion 109 having a small required load torque. The lower model of the image forming apparatus 10 has media limitation (non-correspondence to thick paper and thin paper) and medium productivity. The fixing unit 109 is designed as a common unit that can be commonly used for the upper model and the lower model of the image forming apparatus 10. The difference between the fixing portion 109 when mounted on the upper model and the lower model is that the materials and nip pressures of the second rotating body 202 and the first rotating body 201 are different. The difference in material and nip pressure between the second rotating body 202 and the first rotating body 201 is the difference in the driving torque of the output shaft 204 of the driving gear 205. In this embodiment, the required load torque of the fixing unit 109 incorporated in the upper model is twice the required load torque of the fixing unit 109 incorporated in the lower model.

When the fixing unit 109 is incorporated into a higher-end model, both the first drive unit 206 and the second drive unit 207 are attached to the sheet metal 500. On the other hand, when the fixing unit 109 is incorporated into a lower model, only the first driving unit 206 is attached to the sheet metal 500. The maximum value (maximum torque) of the second driving force supplied from both the first drive unit 206 and the second drive unit 207 to the drive gear 205 is supplied from only the first drive unit 206 to the drive gear 205. Greater than the maximum value of the first driving force to be made. In this embodiment, when both the first drive unit 206 and the second drive unit 207 are attached to the sheet metal 500, the first rotation is performed with respect to the case where only the first drive unit 206 is attached to the sheet metal 500. The torque that can be output at the same rotation speed as the body 201 is doubled. From the above, in order to incorporate the fixing unit 109 into the upper model and the lower model, it is common without changing the first drive unit 206, the second drive unit 207, the sheet metal 500 (ward mounting unit), and other drive rows. Parts can be used.

(Drive and speed control)
Next, the drive and speed control of the first drive unit 206 and the second drive unit 207 executed by the control unit 200 will be described. The first control signal Sigma_D1 that controls the first H-bridge circuit 214 and the second control signal Sigma_D2 that controls the second H-bridge circuit 224 are PWM (pulse width modulation) signals. The control unit 200 executes speed control by adjusting the duty ratio of the PWM signal. The duty ratio is the pulse width of the PWM signal divided by the pulse period. In this embodiment, the control unit 200 executes speed control using PID control (Proportional-Integral-Differential Control) based only on the first detection signal Sigma_ω1 from the first speed sensor 212. The reason for executing the speed control based only on the first detection signal Sigma_ω1 is that the first drive unit 206 is connected to the control unit 200 in both the upper model and the lower model, so that the first detection signal Sigma_ω1 is used. This is because it can be obtained. Further, the speed control can be executed based on only one of the first detection signal Sigma_ω1 and the second detection signal Sigma_ω2.

In this embodiment, the first control signal Sigma_D1 that controls the first drive unit 206 and the second control signal Sigma_D2 that controls the second drive unit 207 are always the same. Since the PWM signal is the result of PID control, this is PWM in both the case of controlling both the first drive unit 206 and the second drive unit 207 and the case of controlling only the first drive unit 206. This is because the signal automatically has an appropriate duty ratio to match the target speed.

For example, in order to rotate the first rotating body 201 at a target speed (for example, 100 rpm) when the required load torque of the fixing portion 109 is 100 millinewton meters (hereinafter referred to as mNm), the following is performed. Set. When both the first drive unit 206 and the second drive unit 207 are used, the output torques of the first drive unit 206 and the second drive unit 207 are set to 50 mNm. When only the first drive unit 206 is used, the output torque of the first drive unit 206 is set to 100 mNm. In PID control, a PWM signal is generated from the difference between the target speed and the current speed (first detection signal Sigma_ω1 in this embodiment), and the PWM signal automatically converges to a duty ratio that matches the target speed. do. For example, when only the first drive unit 206 is used, the PWM signal converges to a duty ratio at which the output torque of the first drive unit 206 becomes 100 mNm. When both the first drive unit 206 and the second drive unit 207 are used, the PWM signal converges to a duty ratio at which the output torques of the first drive unit 206 and the second drive unit 207 are 50 mNm, respectively. ..

When the second drive unit 207 is not attached to the sheet metal 500, as a result, the first control signal Sigma_D1 and the second control signal Sigma_D2 output a torque of 100 mNm from only the first drive unit 206. Settle down to the value you want. However, since the second driving unit 207 is not connected to the control unit 200, as a result of driving the fixing unit 109 only by the first driving unit 206, the fixing unit 109 is driven by the first driving unit 206 at the target speed. It becomes possible to drive. As described above, according to the present embodiment, it is possible to execute the speed control regardless of the presence or absence of the second drive unit 207.

(Fixing operation)
Next, the control when the image forming apparatus 10 performs the fixing operation will be described. As described above, the difference between the upper model and the lower model of the image forming apparatus 10 in this embodiment is the difference in the required load torque of the fixing unit 109. Only the number of drive units (motors) attached is changed according to the required load torque of the fixing unit 109. As a result, the control content of the fixing operation is the same in the upper model and the lower model of the image forming apparatus 10.

First, the control when the higher-end model of the image forming apparatus 10 performs the fixing operation will be described with reference to FIGS. 4 and 5. FIG. 4 is a flow chart showing the drive control of the fixing unit 109. FIG. 5 is a timing chart of the rotation speeds of the first drive unit 206 and the second drive unit 207 and the first control signal Sigma_D1 and the second control signal Sigma_D2 in the higher model. The CPU 250 executes drive control of the fixing unit 109 according to a control program stored in the memory 251. The CPU 250 uses the set value stored in the memory 251 as necessary in the drive control of the fixing unit 109.

When the drive control of the fixing unit 109 is started, the CPU 250 determines at the timing t1 whether or not there is an image forming operation request (S300). When there is no image forming operation request (NO in S300), the CPU 250 waits until there is an image forming operation request (S300). When the user submits a job and receives an image forming operation request (YES in S300), the CPU 250 starts outputting the first control signal Sigma_D1 and the second control signal Sigma_D2 at the timing t2 (S301). According to the first control signal Sigma_D1 and the second control signal Sigma_D2, the driving of the first driving unit 206 and the second driving unit 207 is started. The CPU 250 changes the first control signal Sigma_D1 and the second control signal Sigma_D2 based on the first detection signal Sigma_ω1 from the first speed sensor 212 of the first drive unit 206, and performs speed feedback control. The CPU 250 performs speed feedback control so that the rotation speeds of the first drive unit 206 and the second drive unit 207 become the target rotation speed. Since both the first drive unit 206 and the second drive unit 207 are incorporated in the drive control system 20, both the first drive unit 206 and the second drive unit 207 rotate. Since the first gear 216 of the first drive unit 206 and the second gear 226 of the second drive unit 207 mesh with the drive gear 205, the rotation speed of the first drive unit 206 and the second drive As a result, the rotation speed of the unit 207 becomes the same.

When the rotation speeds of the first drive unit 206 and the second drive unit 207 reach the target rotation speed, the CPU 250 starts image formation (S302). The CPU 250 determines whether or not the image formation is completed (S303). When the image formation is not completed (NO in S303), the CPU 250 continues the image formation until the image formation is completed (S303). When the image formation is completed (YES in S303), at the timing t3, the CPU 250 uses the first control signal Sigma_D1 and the second control signal Sigma_D2 to stop the first drive unit 206 and the second drive unit 207. The output of is stopped (S304). The CPU 250 ends the drive control of the fixing unit 109.

Next, the control when the lower model of the image forming apparatus 10 performs the fixing operation will be described with reference to FIGS. 4 and 6. FIG. 6 is a timing chart of the rotation speeds of the first drive unit 206 and the second drive unit 207 and the timing charts of the first control signal Sigma_D1 and the second control signal Sigma_D2 in the lower model. Since the control content is the same as that of the above-mentioned high-end model, the differences will be mainly described with reference to FIG. The lower model of the image forming apparatus 10 is not provided with the second drive unit 207.

Since the S300 is the same as the high-end model, the description thereof will be omitted. When there is an image forming operation request (YES in S300), the CPU 250 starts outputting the first control signal Sigma_D1 and the second control signal Sigma_D2 at the timing t2 (S301). In S301, the CPU 250 outputs the second control signal Sig_D2, but the second drive unit 207 that receives the second control signal Sig_D2 does not exist. Since the second drive unit 207 does not exist, the rotation speed of the second drive unit 207 remains 0 as shown in FIG. The first control signal Sigma_D1 and the second control signal Sigma_D2 are the same. The fixing unit 109 as a load is driven only by the first driving unit 206 that receives the first control signal Sigma_D1. Since S302 to S304 are the same as the higher-end models, the description thereof will be omitted.

As described above, according to the present embodiment, it is possible to perform a common design using the assist drive technology by a plurality of drive units (motors). By changing the number of drive units of the same type to support from high-end models to low-end models, it is possible to realize a low-cost configuration and high commonality of low-end models even in high-end models.

In this embodiment, the fixing portion is described as a load, but the load is not limited to the fixing portion. The load may be a feed / feed transport unit, a discharge transport unit, a fan drive unit, an intermediate transfer body drive unit, or the like.

According to this embodiment, the driving force 205 is supplied to the driving gear 205 that can drive the first rotating body 201 only by the driving force from the first driving unit 206, and the driving force is also supplied from the second driving unit 207. The second drive unit 207 can be attached to the second attachment unit 507.

10 ... Image forming device 200 ... Control unit 201 ... First rotating body 205 ... Drive gear 206 ... First drive unit 207 ... Second drive unit 506 ... First mounting part 507 ... Second mounting part

Claims (8)

A rotating body that conveys the sheet and
A drive transmission unit that transmits the driving force to the rotating body,
A first drive unit that supplies a first drive force to the drive transmission unit,
The first mounting part to which the first driving part is mounted and
A second mounting part to which the second driving part can be mounted,
A control unit that controls the first drive unit and
With
When the second drive unit is not attached to the second mounting unit, the first drive force is supplied to the drive transmission unit only by the first drive unit.
When the second drive unit is attached to the second mounting unit, the control unit controls the first drive unit and the second drive unit, and controls the first drive unit and the first drive unit and the first drive unit. The second drive unit is an image forming apparatus characterized by supplying a second drive force to the drive transmission unit. The image forming apparatus according to claim 1, wherein the first mounting portion and the second mounting portion are provided on a sheet metal. The sheet is provided with a fixing portion for fixing the toner image.
The image forming apparatus according to claim 1 or 2, wherein the rotating body is provided in the fixing portion. The image according to any one of claims 1 to 3, wherein the first drive unit and the second drive unit are a DC motor, a two-phase brushless motor, or a three-phase brushless motor. Forming device. The drive transmission unit has a drive gear and has a drive gear.
The first drive unit has a first gear that meshes with the drive gear.
Claims 1 to 4, wherein the second drive unit has a second gear that can mesh with the drive gear when the second drive unit is attached to the second mounting portion. The image forming apparatus according to any one of the above. A rotation speed detecting means for detecting the rotation speed of the first driving unit is provided.
The control unit receives a first control signal for controlling the first drive unit and a second control signal for controlling the second drive unit based on the detection result of the rotation speed detecting means. The image forming apparatus according to any one of claims 1 to 5, wherein the image forming apparatus is generated. The image forming apparatus according to any one of claims 1 to 6, wherein the first driving unit and the second driving unit are motors of the same type. The image forming apparatus according to any one of claims 1 to 7, wherein the maximum value of the second driving force is larger than the maximum value of the first driving force.

Images