JP7334533B2 - Conveying device and image forming device - Google Patents

Description

The present invention relates to a conveying device and an image forming apparatus.

In Japanese Patent Laid-Open No. 2004-100000, one of a low-noise mode giving priority to operations with reduced operating noise and a high production mode giving priority to high-speed image forming operations can be selectively executed and set. an image forming apparatus in which the selected operation mode is executed, comprising storage means for storing number information indicating the number of times each operation mode of the low noise mode and the high production mode is executed; and execution indicated by the number information. and setting means for setting an operation mode with a larger number of times as a default operation mode.

Japanese Patent Application Laid-Open No. 2002-100003 discloses a drive unit that rotates to operate a drive unit, a temperature measurement unit that measures the temperature inside an image forming apparatus, a predetermined temperature storage unit that stores a preset reference temperature, and an image forming apparatus. When the temperature measured by the temperature measuring means immediately after the apparatus is powered on is lower than the reference temperature stored in the predetermined temperature storage means, a predetermined rotation speed lower than the steady rotation speed during image formation is detected. low speed rotation determining means for determining to drive the driving means by the number of rotations; and drive control means for controlling the number of rotations of the driving means based on the result of determination by the low speed rotation determining means. An image forming apparatus is disclosed.

In Japanese Patent Application Laid-Open No. 2002-200000, recording paper is fed from a tray to a paper aligning section at feed timing that matches the timing of the image forming process, and skew of the recording paper is corrected in the paper aligning section. A paper conveying device for sending the paper to the image recording unit afterward includes a humidity sensor for detecting the humidity of the installation environment of the main body of the image forming apparatus, and a control means for varying the feed timing based on the detected value of the humidity sensor. A sheet conveying device for an image forming apparatus is disclosed.

JP 2006-259147 A JP-A-2006-208939 JP-A-8-262822

By the way, as a conveying device, a second conveying roll arranged on the upstream side in the conveying direction with respect to the first conveying roll conveys the material to be conveyed so that the material to be conveyed collides with the first conveying roll. A configuration is conceivable in which the material is stopped after slack is formed, and the second transport roll resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported. In this configuration, in a configuration in which the start-up speed of the second transport roll is always constant when transport is restarted, abnormal noise may be generated, for example, in the drive section of the second transport roll.

SUMMARY OF THE INVENTION An object of the present invention is to suppress abnormal noise compared to a configuration in which the start-up speed of the second transport roll is always constant.

In a first mode, a first transport roll is arranged upstream in the transport direction with respect to the first transport roll, and the material to be transported is transported so that the material to be transported collides with the first transport roll. a second conveying roll that stops after forming slack in the material and restarts conveying the material to be conveyed after the first conveying roll starts conveying the material to be conveyed, and an environmental temperature of which is equal to or lower than a reference temperature and a control unit that controls to reduce the start-up speed of the second transport roll when the transport is restarted when the transport is restarted.

A second aspect is the conveying apparatus according to the first aspect, wherein the controller performs control to maintain the startup speed when the environmental temperature exceeds a reference temperature.

In a third aspect, a first transport roll is arranged upstream in the transport direction with respect to the first transport roll, and the material to be transported is transported so that the material to be transported collides with the first transport roll. a second conveying roll that stops after forming slack in the material and restarts conveying the material to be conveyed after the first conveying roll starts conveying the material to be conveyed, and an environmental temperature of which is equal to or lower than a reference temperature and a control unit that performs control to reduce the maximum conveying speed when the conveying is restarted when the conveying is restarted.

A fourth aspect is the conveying apparatus according to the third aspect, wherein the control section performs control to maintain the maximum conveying speed when the environmental temperature exceeds the reference temperature.

In a fifth aspect, the second transport roll restarts the transport after a delay time has elapsed since the first transport roll started transporting the material to be transported, and the control unit controls the environment temperature to be a reference temperature The conveying apparatus according to any one of the first to fourth modes for performing control to shorten the delay time when:

A sixth aspect is the conveying apparatus according to the fifth aspect, wherein the control unit performs control to maintain the delay time when the environmental temperature exceeds the reference temperature.

In a seventh aspect, the second transport roll returns to the normal transport speed after rising to the maximum transport speed when restarting the transport, and the control unit, when the environmental temperature is equal to or lower than the reference temperature, The conveying apparatus according to any one of first to sixth aspects, wherein control is performed to delay the timing of returning from the maximum conveying speed to the normal conveying speed.

An eighth aspect is the conveying apparatus according to the seventh aspect, wherein the controller maintains the timing when the ambient temperature exceeds a reference temperature.

In a ninth aspect, the second transport roll returns to the normal transport speed after rising to the maximum transport speed when restarting the transport, and the control unit, when the environmental temperature is equal to or lower than the reference temperature, The conveying device according to any one of the first to eighth aspects, in which control for increasing the normal conveying speed is performed.

A tenth aspect is the conveying apparatus according to the ninth aspect, wherein the control section performs control to maintain the normal conveying speed when the environmental temperature exceeds the reference temperature.

In an eleventh aspect, when the first transport roll starts transporting the material to be transported on which the slack is formed, the first transport roll rises to the maximum transport speed and then returns to the normal transport speed, and the control unit controls the environment The conveying device according to any one of the first to tenth aspects, in which control is performed to increase the normal conveying speed of the first conveying roll when the temperature is equal to or lower than the reference temperature.

A twelfth aspect is the conveying device according to the eleventh aspect, wherein the control section performs control to maintain the normal conveying speed of the first conveying roll when the environmental temperature exceeds the reference temperature.

A thirteenth aspect is the conveying apparatus according to any one of the first aspect to the twelfth aspect, wherein the capacity of the drive motor that drives the second transfer roll is smaller than the capacity of the drive motor that drives the first transfer roll. is.

A fourteenth aspect is the conveying device according to the thirteenth aspect, wherein the second conveying roll conveys the material to be conveyed downward from the second conveying roll.

A fifteenth aspect is the image forming unit that forms an image on a recording medium as the material to be transported, and the conveying device according to the fourteenth aspect that conveys the recording medium to the image forming unit with the first conveying roll, and the conveying device that conveys, by the second conveying rolls, a recording medium on which an image is formed on one surface and then turned upside down.

According to the structure of the 1st aspect, compared with the structure which the starting speed of a 2nd conveyance roll is always constant, abnormal noise is suppressed.

According to the configuration of the second aspect, wrinkles in the material to be transported are suppressed compared to the configuration in which the rising speed of the second transport roll is constantly reduced.

According to the structure of the 3rd aspect, abnormal noise is suppressed compared with the structure by which the maximum conveyance speed of a 2nd conveyance roll is always constant.

According to the configuration of the fourth aspect, wrinkles in the material to be transported are suppressed compared to the configuration in which the maximum transport speed of the second transport rolls is constantly reduced.

According to the configuration of the fifth aspect, compared to a configuration in which the delay time is always constant, an increase in the required time required for transporting the material to be transported is suppressed.

According to the configuration of the sixth mode, compared with the configuration in which the delay time is always shortened, the remaining slack of the conveyed material is suppressed.

According to the configuration of the seventh aspect, compared to a configuration in which the timing is always constant, an increase in the time required for transporting the material to be transported is suppressed.

According to the configuration of the eighth mode, it is possible to suppress the slack of the conveyed material from remaining as compared with the configuration in which the timing is always delayed.

According to the configuration of the ninth aspect, compared to a configuration in which the normal transport speed is always constant, an increase in the time required for transporting the material to be transported is suppressed.

According to the configuration of the tenth aspect, compared to the configuration in which the normal transportation speed is constantly increased, the remaining slack in the material to be transported is suppressed.

According to the configuration of the eleventh aspect, compared to a configuration in which the normal transport speed of the first transport roll is always constant, an increase in the time required for transporting the material to be transported is suppressed.

According to the configuration of the twelfth aspect, wrinkles in the material to be transported are suppressed compared to the configuration in which the normal transport speed of the first transport roll is constantly increased.

According to the configuration of the thirteenth aspect, in the configuration in which the capacity of the drive motor is smaller than the capacity of the registration motor, abnormal noise is suppressed compared to the configuration in which the rising speed of the second transport roll is always constant.

According to the configuration of the fourteenth mode, in the configuration in which the capacity of the drive motor is smaller than the capacity of the registration motor, the conveying force for conveying the material to be conveyed can be ensured compared to the construction in which the second conveying roll conveys the material to be conveyed upward. .

According to the configuration of the fifteenth aspect, abnormal noise is suppressed as compared with the configuration in which the start-up speed of the second transport roll is always constant.

1 is a schematic diagram showing the configuration of an image forming apparatus according to an embodiment; FIG. FIG. 2 is a schematic diagram exaggerating a state in which a recording medium is skewed in the image forming apparatus according to the present embodiment; 4 is a schematic diagram exaggeratingly showing a state in which slack is formed on the leading end side of a skewed recording medium in the image forming apparatus according to the present embodiment; FIG. FIG. 10 is a side view exaggeratingly showing a state in which slack is formed on the leading end side of the skewed recording medium in the image forming apparatus according to the present embodiment; 2 is a schematic diagram showing a state in which the skew of a recording medium is eliminated in the image forming apparatus according to the present embodiment; FIG. It is a block diagram which shows the hardware constitutions of the control apparatus which concerns on this embodiment. 4 is a diagram showing transport profiles of registration rolls and transport rolls in the image forming apparatus according to the present embodiment; FIG. 4 is a diagram showing transport profiles of registration rolls and transport rolls in the image forming apparatus according to the present embodiment; FIG. FIG. 5 is a side view showing a state in which slack is formed on the leading end side of the skewed recording medium in the image forming apparatus according to the present embodiment; 4 is a diagram showing transport profiles of registration rolls and transport rolls in the image forming apparatus according to the present embodiment; FIG. 4 is a flowchart showing the flow of control processing by the control device according to the embodiment; It is the table|surface which showed the relationship between the fall control and maintenance control by the control apparatus which concerns on this embodiment, and abnormal noise and a wrinkle.

An example of an embodiment according to the present invention will be described below with reference to the drawings.

(Image forming apparatus 10)
The configuration of the image forming apparatus 10 according to this embodiment will be described. FIG. 1 is a schematic diagram showing the configuration of an image forming apparatus 10 according to this embodiment.

An image forming apparatus 10 shown in FIG. 1 is an example of an image forming apparatus that forms an image on a recording medium. Specifically, the image forming apparatus 10 is an electrophotographic image forming apparatus that forms a toner image (an example of an image) on the recording medium P. As shown in FIG. More specifically, the image forming apparatus 10 includes a storage section 12, a discharge section 13, a conveying device 15, an image forming section 14, a fixing device 16, a registration sensor 110, a temperature sensor 120, and a control device 50. and have. Hereinafter, each section (storage section 12, discharge section 13, conveying device 15, image forming section 14, fixing device 16, registration sensor 110, temperature sensor 120, and control device 50) of image forming apparatus 10 will be described.

(Accommodating section 12, discharging section 13 and conveying device 15)
The accommodation unit 12 has a function of accommodating a recording medium P such as paper. The ejection portion 13 is a portion from which the recording medium P is ejected. The transport device 15 has a function of transporting the recording medium P. As shown in FIG. Specifically, the conveying device 15 has a function of conveying the recording medium P from the storage section 12 to the image forming section 14 (secondary transfer position T<b>2 ), the fixing device 16 and the discharge section 13 . Further, when forming images on both sides of the recording medium P, the conveying device 15 reverses the front and back of the recording medium P on which an image is formed on one side (that is, one side), and the image forming section 14 ( It has a function of conveying to the secondary transfer position T2). A specific configuration of the transport device 15 will be described later.

(Image forming unit 14)
The image forming section 14 has a function of forming a toner image (an example of an image) on the recording medium P. As shown in FIG. Specifically, the image forming section 14 has a toner image forming section 22 and a transfer device 17 .

(Toner image forming unit 22)
A plurality of toner image forming units 22 shown in FIG. 1 are provided so as to form a toner image for each color. In the present embodiment, toner image forming units 22 for a total of four colors of yellow (Y), magenta (M), cyan (C), and black (K) are provided. (Y), (M), (C), and (K) shown in FIG. 1 indicate components corresponding to the respective colors.

Since the toner image forming units 22 of each color are configured in the same manner except for the toner used, each portion of the toner image forming unit 22 (Y) in FIG. are doing.

Specifically, the toner image forming section 22 for each color has a photoreceptor drum 32 (photoreceptor) that rotates in one direction (for example, the counterclockwise direction in FIG. 1). Further, each color toner image forming section 22 has a charger 23 , an exposure device 36 , and a developing device 38 .

In the toner image forming unit 22 of each color, the charger 23 charges the photosensitive drum 32 . Further, the exposure device 36 exposes the photosensitive drum 32 charged by the charger 23 to form an electrostatic latent image on the photosensitive drum 32 . Further, the developing device 38 develops the electrostatic latent image formed on the photosensitive drum 32 by the exposure device 36 to form a toner image.

(transfer device 17)
The transfer device 17 shown in FIG. 1 is a device that transfers the toner image formed by the toner image forming section 22 onto the recording medium P. As shown in FIG. Specifically, the transfer device 17 includes a transfer belt 24, a primary transfer roll 26, and a secondary transfer roll 28, as shown in FIG.

The transfer belt 24 is composed of an annular belt wound around a plurality of rolls 42 . The transfer belt 24 rotates in one direction (for example, the clockwise direction in FIG. 1) by rotating any one of the plurality of rolls 42 .

In the transfer device 17, the primary transfer roll 26 transfers the toner image of each color on the photoreceptor drum 32 to the transfer belt 24 as an intermediate transfer body at the primary transfer position T1 between the photoreceptor drum 32 and the primary transfer roll 26. primary transfer overlaid on the

The toner image primarily transferred to the transfer belt 24 is transported to a secondary transfer position T2 between the secondary transfer roll 28 and the transfer belt 24 as the transfer belt 24 rotates. Then, the secondary transfer roll 28 secondarily transfers the toner image conveyed to the secondary transfer position T2 onto the recording medium P. As shown in FIG.

Note that the configuration of the image forming unit 14 is not limited to the configuration described above. For example, the configuration of the image forming section 14 may be a configuration in which the image is transferred directly from the photosensitive drum 32 to the recording medium P without the transfer belt 24 intervening. In this case, for example, a monochrome toner image is transferred to the recording medium P.

(Fixing device 16)
The fixing device 16 shown in FIG. 1 is a device that fixes the toner image transferred onto the recording medium P by the secondary transfer roll 28 . More specifically, as shown in FIG. 1, the fixing device 16 has a heating roll 68 as a heating member and a pressure roll 69 as a pressure member. In the fixing device 16 , the toner image formed on the recording medium P is fixed on the recording medium P by heating and pressing the recording medium P with the heating roll 68 and the pressure roll 69 .

(Specific configuration of conveying device 15)
Specifically, as shown in FIG. , 82, 83, 84. Note that the registration roll 75 is an example of a first transport roll. Also, the transport roll 84 is an example of a second transport roll.

The delivery roll 71 is a roll that delivers the recording medium P accommodated in the accommodation section 12 . The transport rolls 72 , 73 , and 74 are rolls that transport the recording medium P delivered from the storage unit 12 toward the registration rolls 75 . The registration rolls 75 correct the skew of the recording medium P transported from the transport rolls 74 (see FIGS. 2, 3, 4 and 5), and transfer the recording medium P to the image forming section 14 (specifically, , to the secondary transfer position T2).

A specific operation for correcting skew by the registration rolls 75 (hereinafter referred to as skew correction operation) will be described later. Further, skew refers to a state in which the recording medium P is transported in an oblique posture with respect to the transport direction X, as exaggeratedly shown in FIG. In FIGS. 2, 3 and 5, broken lines indicate a state in which the recording medium P is conveyed in a proper posture along the conveying direction X. As shown in FIG.

The transport roll 76 shown in FIG. 1 is a roll that transports the recording medium P transported from the fixing device 16 to the discharge roll 77 . The recording medium P transported to the secondary transfer position T<b>2 by the registration rolls 75 is transported to the fixing device 16 by the secondary transfer rolls 28 and the transfer belt 24 . Further, the recording medium P transported to the fixing device 16 is transported to the transport rollers 76 by the heating roller 68 and pressure roller 69 of the fixing device 16 . Therefore, it can be said that the secondary transfer roll 28, the transfer belt 24, the heating roll 68, and the pressure roll 69 constitute a part of the conveying device 15 that conveys the recording medium P. FIG.

The discharge roll 77 is a roll for discharging the recording medium P transported from the transport roll 76 to the discharge section 13 . Further, when images are formed on both sides of the recording medium P, the ejection rollers 77 switch back the recording medium P on which an image is formed on one side (that is, one side) to thereby , and convey the recording medium P to the conveying roll 81 .

The transport rolls 81 , 82 , 83 , and 84 are rolls that transport the recording medium P whose front and back sides have been reversed by the discharge roll 77 toward the registration rolls 75 . The transport rolls 82, 83, and 84 transport the recording medium P downward.

In this embodiment, the conveying device 15 has a guide portion (not shown) such as a conveying guide arranged between the rolls. As a result, the recording medium P is conveyed along a predetermined conveying route.

Further, the conveying device 15 has a plurality of drive motors (not shown) including a first motor 91, a second motor 92 and a third motor 93 as drive units for driving the respective rolls. The first motor 91 is a drive motor that drives at least the registration rolls 75 . The second motor 92 is a drive motor that drives at least the transport roll 74 . The third motor 93 is a drive motor that drives at least the transport roll 84 .

Further, each of the rolls described above is composed of a pair of rolls, and the plurality of drive motors described above are configured to drive one of the pair of rolls. Furthermore, the capacity (that is, output) of the third motor 93 is smaller than the capacity of the first motor 91 .

The driving of a plurality of drive motors (not shown) including the first motor 91, the second motor 92 and the third motor 93 is controlled by the control device 50 as described later, thereby controlling the operation of each roll. be done.

(registration sensor 110)
The registration sensor 110 is a detection unit that detects the recording medium P. As shown in FIG. Specifically, the registration sensor 110 is arranged between the transport roll 74 and the registration roll 75 and between the transport roll 84 and the registration roll 75 in the transport path of the recording medium P. More specifically, the registration sensor 110 is arranged closer to the registration rolls 75 than the transport rolls 74 and 84 are. The registration sensor 110 is composed of, for example, a transmissive optical sensor, and detects the leading edge and the trailing edge of the recording medium P. As shown in FIG. A signal that detects the leading edge and the trailing edge of the recording medium P is sent to the CPU 51 of the control device 50, which will be described later.

(Temperature sensor 120)
A temperature sensor 120 is a detection unit that detects the environmental temperature of the image forming apparatus 10 . Specifically, the temperature sensor 120 is arranged inside the image forming apparatus 10 and detects the temperature inside the image forming apparatus 10 . More specifically, the temperature sensor 120 is attached to the container 12, for example. Then, the temperature sensor 120 transmits a signal to the CPU 51 of the control device 50, which will be described later, when detecting that the temperature is equal to or lower than a predetermined reference temperature, for example.

Note that the temperature sensor 120 may be configured to detect the environmental temperature around the image forming apparatus 10 outside the image forming apparatus 10, for example. In this configuration, the temperature sensor 120 is attached to the outside of the housing of the image forming apparatus 10, for example.

(control device 50)
The control device 50 is an example of a control section. The control device 50 is a device that controls the operation of each part of the image forming apparatus 10 including the first motor 91 and the second motor 92 of the conveying device 15 . FIG. 6 shows a block diagram showing the hardware configuration of the control device 50. As shown in FIG.

As shown in FIG. 6, the control device 50 has a function as a computer, and includes a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, a RAM (Random Access Memory) 53, a storage 54, and an I/O It has an O (Input/Output) section 57 . Each part of the control device 50 is connected via a bus 59 so as to be able to communicate with each other. Note that the CPU 51 is an example of a processor.

The CPU 51 is a central processing unit, executes various programs including a drive control program, and controls the operation of each section. That is, the CPU 51 reads a program from the ROM 52 or the storage 54 and executes the program using the RAM 53 as a work area. The CPU 51 controls each section of the image forming apparatus 10 and performs various arithmetic processing according to programs recorded in the ROM 52 or the storage 54 .

The ROM 52 stores various programs and various data. The RAM 53 temporarily stores programs or data as a work area. The storage 54 is configured by a HDD (Hard Disk Drive), SSD (Solid State Drive), or the like, and stores various programs including an operating system and various data. The I/O section 57 connects the CPU 51 to each section of the image forming apparatus 10 .

In the control device 50, the CPU 51 controls the first motor 91 and the second motor to perform skew correction control (hereinafter referred to as skew correction control) so that the registration rolls 75 and the transport rolls 74 perform the following skew correction operations. 92.

By the skew correction control, as shown in FIG. 7, the transport rolls 74 start transporting the recording medium P at the normal transport speed while the registration rolls 75 are stopped. After the registration sensor 110 detects the leading edge of the recording medium P, the transport roll 74 starts transporting the recording medium P at a slack creating speed that is lower than the normal transport speed for a predetermined time (slack creating time). Stop after transporting.

As a result, the transport rollers 74 transport the recording medium P so that the recording medium P abuts against the registration rollers 75 in a stopped state, as shown in FIG. 4 . The transport roll 74 is further stopped after a slack (so-called loop) is formed in the recording medium P as shown in FIGS. 3 and 4 . In FIG. 4, the solid line indicates the recording medium P with the leading end abutting the registration roll 75, and the two-dot chain line indicates the slack formed on the leading end side of the recording medium P. As shown in FIG.

Then, as shown in FIG. 7, the registration rolls 75 start conveying the recording medium P (registration conveyance start), and then the conveying rolls 74 resume conveying the recording medium P. As shown in FIG. As a result, the sag formed on the recording medium P is eliminated.

Furthermore, when the recording medium P whose front and back sides have been reversed by the discharge rolls 77 is conveyed to the secondary transfer position T2, the CPU 51 similarly causes the registration rolls 75 and the conveying rolls 84 to perform the following skew correction operations. First, skew correction control is performed on the first motor 91 and the third motor 93 .

By the skew correction control, as shown in FIG. 8, the transport rolls 84 start transporting the recording medium P at the normal transport speed while the registration rolls 75 are stopped. After the registration sensor 110 detects the leading edge of the recording medium P, the transport roll 84 starts transporting the recording medium P at a slack creating speed that is lower than the normal transport speed for a predetermined time (slack creating time). Stop after transporting.

As a result, the transport rolls 84 transport the recording medium P so that the recording medium P abuts against the registration rolls 75 in the stopped state, as shown in FIG. 9 . The transport roll 84 is further stopped after slack is formed in the recording medium P, as shown in FIG. In FIG. 9, the solid line indicates the recording medium P with the leading end abutting the registration roll 75, and the two-dot chain line indicates the slack formed on the leading end side of the recording medium P. As shown in FIG.

Then, as shown in FIG. 10A, the registration rolls 75 start conveying the recording medium P (registration conveyance start), and then the conveying rolls 74 resume conveying the recording medium P. As shown in FIG. As a result, the sag formed on the recording medium P is eliminated.

Specifically, the registration rolls 75 rise to the maximum transport speed when transporting the recording medium P with slack is started, and then return to the normal transport speed (process speed).

Further, the transport rolls 84 resume transporting the recording medium P after a predetermined delay time has elapsed since the registration rolls 75 started transporting the recording medium P. Further, the transport roll 84 rises to a predetermined maximum transport speed when restarting transport of the recording medium P, and then returns to a predetermined normal transport speed (process speed).

Furthermore, in the present embodiment, the CPU 51 sets the maximum transport speed of the transport rollers 84 when transporting the recording medium P is restarted, as shown in FIG. Control for lowering (hereinafter referred to as lowering control) is performed. That is, the decrease control uses a maximum transport speed that is lower than the maximum transport speed (that is, the initially set maximum transport speed) in the normal control. It should be noted that the CPU 51 acquires temperature information on the environmental temperature from the temperature sensor 120, and when the environmental temperature in the temperature information is equal to or lower than the reference temperature, the CPU 51 performs a decrease control.

The reference temperature is, for example, 20°C. The reference temperature is not limited to 20.degree. C., and may be, for example, 25.degree. Moreover, it may have a plurality of stages of reference temperatures (for example, 20° C. and 25° C.), and may be configured to be able to select a plurality of stages of reference temperatures.

Further, in the present embodiment, the CPU 51 maintains the rise time for raising the transport rolls 84 to the maximum transport speed in the reduction control. That is, in the decrease control, the rise time in normal control (that is, the initially set rise time) is used.

As described above, in the decrease control, the maximum transport speed of the transport roll 84 is decreased while the rise time is maintained, so the start-up speed of the transport roll 84 is decreased when the transport of the recording medium P is restarted. .

In other words, the reduction control can also be said to be control for reducing the start-up speed of the transport roll 84 when transport of the recording medium P is restarted when the ambient temperature is equal to or lower than the reference temperature. The start-up speed corresponds to the acceleration (slope shown in FIG. 10) from speed 0 (zero) to the maximum transport speed.

Furthermore, the CPU 51 shortens the delay time in the decrease control. That is, the decrease control uses a delay time that is shorter than the delay time (that is, the initially set delay time) in the normal control.

Further, in the reduction control, the CPU 51 delays the return timing of returning the transport rollers 84 from the maximum transport speed to the normal transport speed. That is, in the decrease control, a return timing that is delayed from the return timing in the normal control (that is, the initially set return timing) is used. As a result, the driving time of the transport roll 84 at the maximum transport speed is extended.

In other words, the CPU 51 extends the driving time of the transport roll 84 at the maximum transport speed in the decrease control.

Furthermore, the CPU 51 increases the normal transport speed of the transport roll 84 in the decrease control. That is, in the reduction control, a normal transport speed higher than the normal transport speed of the transport rollers 84 in the normal control (that is, the initially set normal transport speed) is used.

Furthermore, the CPU 51 increases the normal conveying speed of the registration rolls 75 in the reduction control. In other words, in the decrease control, a normal conveying speed higher than the normal conveying speed of the registration rolls 75 (that is, the initially set normal conveying speed) is used in the normal control.

On the other hand, when the ambient temperature exceeds the reference temperature, the CPU 51 performs control (hereinafter referred to as maintenance control) to maintain the maximum transport speed of the transport rollers 84 when transporting the recording medium P is resumed (see FIG. 10 ( A)). That is, in the maintenance control, the maximum conveying speed in normal control (that is, the initially set maximum conveying speed) is used. Note that the CPU 51 acquires temperature information on the environmental temperature from the temperature sensor 120, and performs maintenance control when the environmental temperature in the temperature information exceeds the reference temperature.

Further, in the present embodiment, the CPU 51 maintains the start-up time for raising the transport rolls 84 to the maximum transport speed in the maintenance control. That is, in command control, the rise time in normal control (that is, the initially set rise time) is used.

In this way, the maintenance control maintains the rising time and the maximum conveying speed of the conveying roll 84, so that the rising speed of the conveying roll 84 when the conveying of the recording medium P is restarted is also maintained. In other words, the maintenance control can also be said to be control for maintaining the start-up speed of the transport rolls 84 when transporting the recording medium P is restarted when the environmental temperature exceeds the reference temperature.

Furthermore, the CPU 51 maintains the delay time in maintenance control. That is, the maintenance control uses the delay time in the normal control (that is, the initially set delay time).

Further, in the maintenance control, the CPU 51 maintains the return timing for returning the transport rollers 84 from the maximum transport speed to the normal transport speed. That is, the maintenance control uses the return timing (that is, the initially set return timing) in the normal control. As a result, the driving time of the transport roll 84 at the maximum transport speed is maintained.

In other words, the CPU 51 maintains the driving time of the transport roll 84 at the maximum transport speed in the maintenance control.

Furthermore, the CPU 51 maintains the normal conveying speed of the conveying roll 84 in maintenance control. That is, in the maintenance control, the normal conveying speed of the conveying rollers 84 in the normal control (that is, the initially set normal conveying speed) is used.

Further, the CPU 51 maintains the normal conveying speed of the registration rolls 75 in maintenance control. That is, in the maintenance control, the normal conveying speed of the registration rolls 75 in the normal control (that is, the initially set normal conveying speed) is used.

(Action according to this embodiment)
Next, the operation of this embodiment will be described. FIG. 11 is a flowchart showing the flow of control processing executed by the control device 50. As shown in FIG.

This control process is performed by the CPU 51 reading out a control program from the ROM 52 or the storage 54 and executing it. In this embodiment, this control process is performed when the CPU 51 acquires an instruction to form images on both sides of the recording medium P, for example.

As shown in FIG. 11, when this control process is started, the CPU 51 first acquires temperature information on the ambient temperature from the temperature sensor 120 (step S102).

Next, the CPU 51 determines whether or not the environmental temperature in the temperature information acquired from the temperature sensor 120 is below the reference temperature (step S104).

When the CPU 51 determines in step S104 that the environmental temperature in the temperature information obtained from the temperature sensor 120 is equal to or lower than the reference temperature (for example, 20° C.), it performs a decrease control (step S106), and executes this control process. finish.

In the reduction control, the CPU 51 reduces the maximum transport speed of the transport rollers 84 when transporting the recording medium P is resumed. Further, in the reduction control, the CPU 51 reduces the start-up speed (inclination shown in FIG. 10B) of the transport roll 84 when transporting the recording medium P is resumed. Also, the CPU 51 shortens the delay time in the reduction control.

Furthermore, in the reduction control, the CPU 51 delays the return timing of returning the transport rollers 84 from the maximum transport speed to the normal transport speed. Further, the CPU 51 increases the normal transport speed of the transport roll 84 in the decrease control. In addition, the CPU 51 increases the normal conveying speed of the registration rolls 75 in the reduction control.

On the other hand, when the CPU 51 determines in step S104 that the environmental temperature in the temperature information obtained from the temperature sensor 120 exceeds the reference temperature, it performs maintenance control (step S108), and ends this control process.

In maintenance control, the CPU 51 maintains the maximum transport speed of the transport rollers 84 when transporting the recording medium P is resumed. Further, in maintenance control, the CPU 51 maintains the start-up speed (inclination shown in FIG. 10A) of the transport roll 84 when transporting the recording medium P is resumed. Further, the CPU 51 maintains the delay time in maintenance control.

Furthermore, in maintenance control, the CPU 51 maintains the return timing for returning the transport rollers 84 from the maximum transport speed to the normal transport speed. Further, the CPU 51 maintains the normal conveying speed of the conveying roll 84 in maintenance control. Further, the CPU 51 maintains the normal conveying speed of the registration rolls 75 in maintenance control.

As described above, in the present embodiment, when the environmental temperature is equal to or lower than the reference temperature, the CPU 51 determines the maximum value of the transport roll 84 when transporting the recording medium P is restarted, as shown in FIG. 10B. Decrease control is performed to decrease the conveying speed (step S106).

Here, in the configuration in which the maximum transport speed of the transport roll 84 is always constant (hereinafter referred to as the first configuration), when the environmental temperature is equal to or lower than the reference temperature, when the transport roll 84 is started up, the third motor 93 abnormal noise may occur. This is presumed to be due to the fact that when the environmental temperature becomes equal to or lower than the reference temperature, the resonance points of the third motor 93 tend to coincide with each other, and the resonance generates abnormal noise. Note that this resonance is likely to occur when a drive motor with a small capacity is used.

On the other hand, in the present embodiment, as described above, when the environmental temperature is equal to or lower than the reference temperature, the CPU 51 determines when the conveyance of the recording medium P is restarted, as shown in FIG. 10B. Since the maximum conveying speed of the conveying roll 84 is reduced, abnormal noise generated by the third motor 93 when starting the conveying roll 84 is suppressed compared to the first configuration (see FIG. 12).

Since the abnormal noise generated in the third motor 93 is suppressed in this way, the capacity of the third motor 93 is smaller than the capacity of the first motor 91, and the third motor 93 has a capacity similar to that of the present embodiment. This is particularly effective in configurations where sound is likely to occur.

Further, in the present embodiment, the CPU 51 reduces the start-up speed (inclination shown in FIG. 10B) of the transport roll 84 when transporting the recording medium P is resumed in the decrease control.

Here, in a configuration (hereinafter referred to as a second configuration) in which the transport roll 84 starts up at a constant speed, when the environmental temperature is equal to or lower than the reference temperature, the third motor 93 abnormal noise may occur. This is presumed to be due to the fact that when the environmental temperature becomes equal to or lower than the reference temperature, the resonance points of the third motor 93 tend to coincide with each other, and the resonance generates abnormal noise. Note that this resonance is likely to occur when a drive motor with a small capacity is used.

On the other hand, in the present embodiment, as described above, the CPU 51 determines the start-up speed of the transport roll 84 (inclination shown in FIG. 10B) when restarting transport of the recording medium P in the reduction control. is reduced, noise generated by the third motor 93 when the transport roll 84 is raised is suppressed as compared with the second configuration (see FIG. 12).

Moreover, in this embodiment, the CPU 51 shortens the delay time in the decrease control. Here, in a configuration in which the delay time is always constant (hereinafter referred to as a third configuration), the recording medium P to the target position (that is, the secondary transfer position T2).

On the other hand, in the present embodiment, the CPU 51 shortens the delay time in the decrease control. Suppressed. As a result, compared to the third configuration, a decrease in productivity for forming an image on the recording medium P is suppressed.

Furthermore, in the reduction control, the CPU 51 delays the return timing of returning the transport rollers 84 from the maximum transport speed to the normal transport speed. Here, in the configuration in which the return timing is always constant (hereinafter referred to as the fourth configuration), the recording medium P to the target position (that is, the secondary transfer position T2).

On the other hand, in the present embodiment, the CPU 51 delays the return timing in the reduction control, so the increase in the time required to transport the recording medium P to the secondary transfer position T2 is suppressed compared to the fourth configuration. be done. As a result, compared to the fourth configuration, a decrease in productivity for forming an image on the recording medium P is suppressed.

Further, in the present embodiment, the CPU 51 increases the normal conveying speed of the conveying rollers 84 in the reduction control. Here, in the configuration in which the normal transport speed of the transport roll 84 is always constant (hereinafter referred to as the fifth configuration), the maximum transport speed of the transport roll 84 is decreased, or the start-up speed of the transport roll 84 is decreased. Accordingly, the time required to convey the recording medium P to the target position (that is, the secondary transfer position T2) increases.

In contrast, in the present embodiment, the CPU 51 increases the normal transport speed of the transport roll 84 in the reduction control. An increase in required time is suppressed. As a result, compared to the fifth configuration, a decrease in productivity for forming an image on the recording medium P is suppressed.

Further, in the present embodiment, the CPU 51 increases the normal conveying speed of the registration rolls 75 in the reduction control. Here, in the configuration in which the normal transport speed of the registration rolls 75 is always constant (hereinafter referred to as the sixth configuration), the maximum transport speed of the transport rolls 84 is reduced, or the start-up speed of the transport rolls 84 is decreased. Accordingly, the time required to convey the recording medium P to the target position (that is, the secondary transfer position T2) increases.

In contrast, in the present embodiment, the CPU 51 increases the normal conveying speed of the registration rolls 75 in the reduction control. An increase in required time is suppressed. As a result, compared to the sixth configuration, a decrease in productivity for forming an image on the recording medium P is suppressed.

On the other hand, in this embodiment, when the environmental temperature exceeds the reference temperature, the CPU 51 performs maintenance control to maintain the maximum transport speed of the transport rollers 84 when transporting the recording medium P is resumed (step S108).

Here, in the configuration (hereinafter referred to as the seventh configuration) in which the maximum transport speed of the transport rolls 84 is always lowered, when the environmental temperature exceeds the reference temperature, when the transport rolls 84 resume transport of the recording medium P, The recording medium P may be wrinkled. This is because, when the ambient temperature exceeds the reference temperature, the recording medium P softens and becomes less elastic, and the twisted recording medium P is strongly pulled by the decrease in the maximum transport speed of the transport rollers 84 due to the formation of flexure. It is assumed that the recording medium P is wrinkled.

In contrast, in the present embodiment, as described above, the CPU 51 maintains the maximum transport speed of the transport rollers 84 when transporting the recording medium P is resumed when the environmental temperature exceeds the reference temperature. Compared to the seventh configuration, wrinkles generated in the recording medium P are suppressed when the transportation of the recording medium P is restarted by the transportation rollers 84 (see FIG. 12).

Further, in the present embodiment, the CPU 51 maintains the start-up speed (inclination shown in FIG. 10A) of the transport roll 84 when transporting the recording medium P is resumed in the maintenance control.

Here, in the configuration (hereinafter referred to as the eighth configuration) in which the start-up speed of the transport roll 84 is always lowered, when the environmental temperature exceeds the reference temperature, when the transport roll 84 resumes transporting the recording medium P, The recording medium P may be wrinkled. This is because when the ambient temperature exceeds the reference temperature, the recording medium P softens and becomes less elastic, and the recording medium P, which has been twisted due to the formation of flexure, is strongly pulled by the decrease in the start-up speed of the transport roll 84. It is assumed that the recording medium P is wrinkled.

On the other hand, in the present embodiment, as described above, the CPU 51 determines the start-up speed of the transport roll 84 (inclination shown in FIG. 10A) when restarting transport of the recording medium P in the maintenance control. is maintained, wrinkles occurring in the recording medium P when the transport of the recording medium P is restarted by the transport rollers 84 are suppressed compared to the eighth configuration (see FIG. 12).

Further, in this embodiment, the CPU 51 maintains the normal transport speed of the registration rolls 75 in maintenance control. Here, in a configuration in which the normal transport speed of the registration rolls 75 is always increased (hereinafter referred to as a twelfth configuration), the feeding amount of the recording medium P by the registration rolls 75 is increased. The medium P is pulled, and the recording medium P is likely to be wrinkled.

On the other hand, in this embodiment, the CPU 51 maintains the normal transport speed of the registration rolls 75 in the maintenance control. Wrinkles occurring in the recording medium P are suppressed.

Moreover, in this embodiment, the CPU 51 maintains the delay time in maintenance control. Here, in a configuration in which the delay time is always shortened (hereinafter referred to as a ninth configuration), the feeding amount of the recording medium P by the transport rollers 84 increases, so the slack of the recording medium P is not eliminated and remains. Sometimes.

On the other hand, in this embodiment, the CPU 51 maintains the delay time in the maintenance control. remaining is suppressed.

Further, in this embodiment, the CPU 51 maintains the return timing for returning the transport roll 84 from the maximum transport speed to the normal transport speed in the maintenance control. Here, in a configuration in which the return timing is always delayed (hereinafter referred to as a tenth configuration), the feeding amount of the recording medium P by the transport rollers 84 increases, so the slack in the recording medium P is not eliminated and remains. There is

On the other hand, in this embodiment, the CPU 51 maintains the return timing in the maintenance control. remaining is suppressed.

Further, in the present embodiment, the CPU 51 maintains the normal transport speed of the transport rollers 84 in maintenance control. Here, in a configuration (hereinafter referred to as an eleventh configuration) in which the normal transport speed of the transport rolls 84 is constantly increased, the amount of feeding of the recording medium P by the transport rolls 84 increases, so the slack of the recording medium P is not eliminated, The slack may remain.

On the other hand, in the present embodiment, the CPU 51 maintains the normal transport speed of the transport rollers 84 in the maintenance control. Remaining slack of the recording medium P is suppressed.

Further, in the present embodiment, although the capacity (that is, the output) of the third motor 93 is smaller than the capacity of the first motor 91, the transport roll 84 transports the recording medium P downward, so that the transport roll 84 is used for recording. Compared to the configuration in which the medium P is transported upward, the transport roll 84 can secure the transport force of the recording medium P. FIG.

(Modification)
Although the transport roll 84 is used as an example of the second transport roll in the present embodiment, it is not limited to this. An example of the second transport roll may be the transport roll 74 .

Further, in the present embodiment, in the reduction control, the maximum transport speed of the transport rolls 84 is reduced while the rise time is maintained. Although the speed (inclination shown in FIG. 10) is reduced, the present invention is not limited to this. For example, in the reduction control, the start-up speed of the transport rolls 84 may be decreased by lengthening the rising time while maintaining the maximum transport speed of the transport rolls 84 .

Further, in the present embodiment, the speed at which the conveying rolls 84 are raised is reduced in the reduction control, but this is not the only option. For example, in the decrease control, the maximum transport speed of the transport rolls 84 may be decreased by shortening the rise time without decreasing the start-up speed of the transport rolls 84 .

Moreover, in the present embodiment, the delay time is shortened in the decrease control, but the present invention is not limited to this. For example, the configuration may be such that the delay time is maintained in the decrease control.

Further, in the present embodiment, the return timing for returning the transport rollers 84 from the maximum transport speed to the normal transport speed is delayed in the reduction control, but the present invention is not limited to this. For example, in the reduction control, the configuration may be such that the return timing is maintained.

Moreover, in the present embodiment, the normal transport speed of the transport roll 84 is increased in the reduction control, but the present invention is not limited to this. For example, the configuration may be such that the normal transport speed of the transport roll 84 is maintained.

Further, in the present embodiment, the normal conveying speed of the registration rolls 75 is increased in the reduction control, but the present invention is not limited to this. For example, the configuration may be such that the normal transport speed of the registration rolls 75 is maintained.

Further, in the present embodiment, the configuration is such that the reduction control is performed when the environmental temperature is equal to or lower than the reference temperature, but the present invention is not limited to this. For example, the configuration may be such that the reduction control is performed when the environmental temperature is equal to or lower than the reference temperature and the environmental humidity is equal to or lower than the reference humidity. In this configuration, maintenance control is performed, for example, when the environmental temperature exceeds the reference temperature or the environmental humidity exceeds the reference humidity. The environmental humidity is detected inside the image forming apparatus 10 or outside the image forming apparatus 10 and around the image forming apparatus 10 . Also, as an example of the reference humidity, for example, humidity such as 50% is used.

The present invention is not limited to the above-described embodiments, and various modifications, changes, and improvements are possible without departing from the scope of the invention. For example, the modifications shown above may be configured by appropriately combining a plurality of them.

10 Image forming device 14 Image forming unit 15 Conveying device 50 Control device (an example of a control unit)
75 registration roll (an example of the first transport roll)
84 transport roll (an example of a second transport roll)
P recording medium (an example of material to be conveyed)

Claims (18)

a first transport roll;
It is arranged on the upstream side in the conveying direction with respect to the first conveying roll, and stops after forming slack in the conveyed material by conveying the conveyed material so that the conveyed material hits the first conveying roll, and a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
When the environmental temperature is equal to or lower than the reference temperature, the starting speed of the second transport roll when restarting the transport while maintaining the starting speed of the first transport roll that started transporting the material to be transported a control unit that controls to reduce the
A conveying device comprising a The control unit
The conveying apparatus according to claim 1, wherein control is performed to maintain the start-up speed when the environmental temperature exceeds the reference temperature. a first transport roll;
It is arranged on the upstream side in the conveying direction with respect to the first conveying roll, and stops after forming slack in the conveyed material by conveying the conveyed material so that the conveyed material hits the first conveying roll, and a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
When the environmental temperature is equal to or lower than the reference temperature , the maximum conveying speed of the second conveying roll when restarting the conveying while maintaining the maximum conveying speed of the first conveying roll that started conveying the material to be conveyed a control unit that controls to reduce the
A conveying device comprising a The control unit
The conveying apparatus according to claim 3, wherein control is performed to maintain the maximum conveying speed of the second conveying roll when the environmental temperature exceeds the reference temperature. The second transport roll is
restarting the transport after a delay time has elapsed since the first transport roll started transporting the material to be transported;
The control unit
The conveying apparatus according to any one of claims 1 to 4, wherein control is performed to shorten the delay time when the ambient temperature is equal to or lower than a reference temperature. The control unit
The conveying apparatus according to claim 5, wherein control is performed to maintain the delay time when the environmental temperature exceeds the reference temperature. a first transport roll;
It is arranged on the upstream side in the conveying direction with respect to the first conveying roll, and stops after forming slack in the conveyed material by conveying the conveyed material so that the conveyed material hits the first conveying roll, and a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
a control unit that controls to reduce the start-up speed of the second transport roll when the transport is restarted when the environmental temperature is equal to or lower than the reference temperature;
with
The second transport roll is
When the transportation is resumed, after the transportation speed is raised to the maximum transportation speed, the transportation speed is returned to the normal transportation speed,
The control unit
When the environmental temperature is equal to or lower than a reference temperature, control is performed to delay the timing of returning from the maximum conveying speed to the normal conveying speed.
Conveyor. a first transport roll;
arranged upstream in the conveying direction with respect to the first conveying roll, conveying the material to be conveyed so that the material to be conveyed collides with the first conveying roll, thereby forming slack in the material to be conveyed, and then stopping; a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
a control unit that controls to reduce the maximum conveying speed of the second conveying roll when the conveying is restarted when the environmental temperature is equal to or lower than the reference temperature;
with
The second transport roll is
When the transportation is resumed, after the transportation speed is raised to the maximum transportation speed, the transportation speed is returned to the normal transportation speed,
The control unit
A conveying device that delays the timing of returning from the maximum conveying speed to the normal conveying speed when the environmental temperature is equal to or lower than a reference temperature. The control unit
Maintain the timing when the ambient temperature exceeds the reference temperature
9. A conveying device according to claim 7 or 8. a first transport roll;
It is arranged on the upstream side in the conveying direction with respect to the first conveying roll, and stops after forming slack in the conveyed material by conveying the conveyed material so that the conveyed material hits the first conveying roll, and a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
a control unit that controls to reduce the start-up speed of the second transport roll when the transport is restarted when the environmental temperature is equal to or lower than the reference temperature;
with
The second transport roll is
When the transportation is resumed, after the transportation speed is raised to the maximum transportation speed, the transportation speed is returned to the normal transportation speed,
The control unit
A conveying device that performs control to increase the normal conveying speed when the ambient temperature is equal to or lower than a reference temperature . a first transport roll;
arranged upstream in the conveying direction with respect to the first conveying roll, conveying the material to be conveyed so that the material to be conveyed collides with the first conveying roll, thereby forming slack in the material to be conveyed, and then stopping; a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
a control unit that controls to reduce the maximum conveying speed of the second conveying roll when the conveying is restarted when the environmental temperature is equal to or lower than the reference temperature;
with
The second transport roll is
When the transportation is resumed, after the transportation speed is raised to the maximum transportation speed, the transportation speed is returned to the normal transportation speed,
The control unit
A conveying device that performs control to increase the normal conveying speed when the ambient temperature is equal to or lower than a reference temperature . The control unit
When the environmental temperature exceeds the reference temperature, control is performed to maintain the normal conveying speed.
12. A conveying device according to claim 10 or 11. a first transport roll;
It is arranged on the upstream side in the conveying direction with respect to the first conveying roll, and stops after forming slack in the conveyed material by conveying the conveyed material so that the conveyed material hits the first conveying roll, and a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
a control unit that controls to reduce the start-up speed of the second transport roll when the transport is restarted when the environmental temperature is equal to or lower than the reference temperature;
with
The first transport roll is
When starting to convey the material to be conveyed on which the slack is formed, the conveying speed rises to the maximum conveying speed and then returns to the normal conveying speed,
The control unit
When the environmental temperature is equal to or lower than the reference temperature, control is performed to increase the normal conveying speed of the first conveying roll.
Conveyor. a first transport roll;
It is arranged on the upstream side in the conveying direction with respect to the first conveying roll, and stops after forming slack in the conveyed material by conveying the conveyed material so that the conveyed material hits the first conveying roll, and a second transport roll that resumes transporting the material to be transported after the first transport roll starts transporting the material to be transported;
a control unit that performs control to reduce the maximum conveying speed of the second conveying roll when the conveying is restarted when the environmental temperature is equal to or lower than the reference temperature;
with
The first transport roll is
When starting to convey the material to be conveyed on which the slack is formed, the conveying speed rises to the maximum conveying speed and then returns to the normal conveying speed,
The control unit
When the environmental temperature is equal to or lower than the reference temperature, control is performed to increase the normal conveying speed of the first conveying roll.
Conveyor. The control unit
When the environmental temperature exceeds the reference temperature, perform control to maintain the normal conveying speed of the first conveying roll
15. A conveying device according to claim 13 or 14. The capacity of the drive motor that drives the second transport roll is smaller than the capacity of the drive motor that drives the first transport roll.
Conveying device according to any one of claims 1 to 15. The second transport roll transports the material to be transported downward from the second transport roll.
17. A transport device according to claim 16. an image forming unit that forms an image on a recording medium as the conveyed material;
18. The conveying device according to claim 17, wherein the recording medium is conveyed to the image forming unit by the first conveying roll, and the recording medium having an image formed on one surface thereof and then turned upside down is conveyed to the second conveying roll. The conveying device that conveys with a conveying roll;
An image forming apparatus comprising: