JPS60171908A - Endless belt driving device - Google Patents

Abstract

PURPOSE:To reduce the shaking speed of a belt in the width direction by obtaining the corrected value of the siding speed of a belt, determining the quantity of deviation to determine the deviating position, and judging the deviating position abnormal when it is beyond a defined range. CONSTITUTION:When a photosensor S1 is turned on due to the first zigzag movement of a belt 1, a control part makes a zigzag-movement correcting roller deviate in a direction to be corrected, by a define quantity. Then, as a photosensor S2 is turned on, the roller is made deviate by twice the defined quantity in the opposite direction, and the trend of deviation is obtained from the difference in siding speed between both deviations, to carry out initial stage setting for the quantity and position of deviation. After that, the quantity of deviation is corrected in such a way that the siding speed to right and left is made equal while that the quantity of deviation is gradually reduced. In this case, it the deviating position of the zigzag-movement correcting roller is beyond a proper range, it is judged abnormal and the unit is shut down. Due to this construction, the shaking speed of the belt in the width direction can be suppressed small while preventing the damage of the belt due to an abnormal deviation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a device for endlessly driving an endless belt while correcting its meandering.

[Prior art] In general, when it is necessary to hold the conveyed object on a flat surface, such as when conveying a sheet-like object (such as two boards of paper), m
A conveying device using an endless belt (hereinafter referred to as an endless belt) is often used as a conveying means.

In such a conveying device, since the endless bell 1 which serves as a member for placing (supporting) an object forms a flat surface, it is relatively easy to hold the object on a flat surface.

FIG. 1 is used in an electrostatic photocopier or the like that uses a so-called belt photoreceptor as a sensor. A drive unit for the belt photoreceptor is shown.

In this drive unit, the belt photoreceptor OB is stretched between the drive roller R1 and the driven roller R2-84, and the belt photoreceptor OB is driven in the direction of the arrow.

This device brings a transfer paper into close contact with a belt photoreceptor OB, transfers the toner image formed on the belt photoreceptor onto the transfer paper, and then conveys the transfer paper to a fixing section.

By the way, as is well known, in such an endless belt drive device, so-called meandering development in which the endless belt shifts in its width direction always occurs.

The main reasons for this are that, for example, in the apparatus shown in FIG. It is mentioned that they are not parallel.

Conventionally, the meandering of the Pel 1 to the photoreceptor OB has been corrected by, for example, providing the roller R2 with the function of a meandering correction roller.

That is, a meandering detection means is provided to detect that the belt photoreceptor OB has meandered, and when meandering occurs, the roller R2
The axis of the belt photoreceptor O is deflected in the opposite direction to the meandering direction.
B is moved, thereby correcting the meandering of the belt photoreceptor OB.

By the way, as mentioned above, there are two main causes of meandering,
Meandering development due to these causes may combine to increase the amount of meandering, and therefore, the roller R2 may be deflected suddenly and greatly in order to correct the meandering of the belt photoreceptor OB.

Since each copying process station is provided close to the belt photoreceptor OB, if the roller R2 is suddenly deflected greatly as described above, the belt photoreceptor OB
The speed of movement in the width direction of the belt increases, and its surface and side edges come into contact with the casing, side plate, etc. of the device forming the station, and as a result, the belt photoreceptor may be damaged.

Furthermore, since the amount of belt displacement in the width direction during image formation increases, there is a risk that the copied image will be distorted or the developing unit will malfunction.

In addition, in recent years, high-speed copying machines using a belt photoreceptor and having a copying speed of about 150 sheets/min have been put into practical use. In such a high-speed copying machine, since the process speed is high, it is necessary to drive one photosensitive belt at high speed, and therefore, the above-mentioned disadvantages become noticeable.

In addition, such inconveniences are not limited to the above-mentioned copying machine.
Similar problems occur in other devices that utilize endless belt drive devices.

[Objective] The present invention was made in order to eliminate the above-mentioned disadvantages, and an object of the present invention is to provide an endless belt drive device that can gradually reduce the meandering speed of the endless belt.

[Configuration] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 shows an embodiment of the invention. In this embodiment, the present invention is applied to a bell l-unit of a copying machine using a belt photoreceptor.

In the same figure, a drive roller 11. Meandering correction roller 12. Driven roller 1
3 and a driven roller 14, and is driven.

Each of these rollers 11, 12, 13, and 14 is supported between side plates SBI and SB2, which will be described later, and their positional relationship is maintained.

Furthermore, 15J6, 17, and 18 are flatness maintenance plates for maintaining the flatness of the belt photoreceptor 1 in each process station (not shown) of cleaning, charging, exposure, and development.

Reference numeral 21 denotes a sensor section that detects meandering of the belt photoreceptor 1 and the timing to start the copying process.

35 is a reference sensor for setting the reference position of the meandering correction roller 12, and 3G is a step motor for controlling the deflection position of the meandering correction roller 12.

37 is a deflection plate for deflecting the meandering correction roller 12 in the directions of arrows C and D, 38 is a roller support plate that supports the meandering correction roller 12, and 39 is a spring for making the meandering correction roller 12 function as a tension roller. .

A release lever 40 is connected to the roller support plate 38 via a link 40a. Therefore, when the release lever 40 is rotated in the direction of the arrow, the roller support plate 38
moves in the direction of the arrow, and the tension applied to the belt photoreceptor 1 by the meandering correction roller 12 is released.

Thereby, the belt photoreceptor I can be removed from the belt unit.

FIG. 3, FIG. 4, and FIG. 5 show the configuration of the vicinity of the sensor section 21.

As shown in the figure, the sensor section 2] is a reflective photosensor 5.
A substrate 22.1 to S4 are arranged. It consists of a support plate 23 that supports this substrate 22 and a sensor guide 24 that guides this support plate 23.

Further, a terminal for output signals of the photosensors 31 to S4 is attached to one end of the substrate 22, and this terminal is connected to the side plate SB2.
It is inserted into the connector CN attached to the. Furthermore, the sensor guide 24 is provided with a presser spring 25, which fixes the support plate 23 within the sensor guide 24.

Black conductive bands BE are attached to both sides of the belt photoreceptor 1 for grounding, and reflective marks MK are placed at appropriate locations on the conductive bands BH to generate process start timing.
is provided. Further, since a metal roller is usually used as the driven roller 14, its surface reflects light well.

Therefore, the belt photoreceptor 1 rotates and the reflective mark MK
is photosensor S3. Once detected in S4, the graphic copying process is started.

Further, when the belt photoreceptor 1 is running normally without meandering, the photosensor 31. In order for both S2 to detect the driven roller 14, an ON signal is output to a control section to be described later, but when the belt photoreceptor 1 meanders in any direction, the black conductive band BE is detected by the photosensor 51. Either S2 is detected and its output is inverted.

This allows the control section to know that the belt photoreceptor 1 has meandered and its direction.

In Figure 3, SBI is the front plate of the Bell I unit.

5132 is the rear side plate of the belt unit, and MS is the front side plate of the copying machine main body.

FIG. 6 shows the drive section of the meandering correction roller 12.

In FIG. 1, 41.42 is a stepped screw, 43.44 is a stepped stud, 37 is a deflection plate, 38.45 is a roller support plate, and 38a and 45a are fixed to the roller support plates 38 and 45. Stepped.

Tad, 46 is a nine-sided shaft fixed to the roller support plate 40, 47
is a bearing for the shaft 46, 49 and 50 are fixedly attached to the roller support plate 38 and the deflection plate 37, and the meandering correction roller 12
A boss 51 receives the shaft 48 of the front side plate SBI and the rear side plate S
This is the axis that connects B2.

Further, the pin 52 arranged on the deflection plate 37 forms part of a power transmission system that transmits the power of the step motor 36 to the deflection plate 37, as will be described later.

As shown in FIG.
The shaft 48 is connected to the boss 49.50 through the bearing 55, and a slide member 57 is inserted into the bearing 55.
It is slidably supported in the longitudinal direction within.

Further, a spring 39 is stretched between the stepped studs 38a and 43, and a spring 58 is stretched between the stepped studs 44 and 45a. Therefore, the action of the spring 39 causes the roller support plate to
8 slides toward the stepped stud 43,
Under the action of the spring 58, the roller support plate 45 and the deflection plate 37 slide together toward the stepped stud 44, and as a result, tension is applied to the belt photoreceptor 1 by the meandering correction roller 12.

In addition, Fig. 7 shows the release lever 40 in the release position! Cow&
There are 6+ and 11 pieces.
This is a shaft that connects the link 40a on the front side plate side of the l'slever 40 and the link 40b on the rear side plate side.

FIG. 8 shows the meandering correction roller 12 from the step motor 36.
It shows the power transmission system to.

A step motor 3 is attached to the pedestal BS arranged on the rear side plate SB2.
6 is fixed, and a microphone gear 60 is attached to the shaft of the step motor 36. A lead screw 62 is coaxially connected to a microphone gear 61 that is paired with the microphone gear 60, and a slider 63 with fingers is connected to the lead screw 62.
are screwed together.

The slider 63 supports the pin 52 attached to the deflection plate 37 with its fingers, and one side of the slider 63 is in contact with the surface of the deflection plate 37.

Note that the lead screw 62 is supported between a support plate B and 882 formed by cutting and raising a part of the rear side plate SB2.

Now, assuming that the lead screw 62 is formed with a right-hand thread, when the step motor 36 operates in the J (clockwise) direction, the slider 63 moves downward in the figure.

As a result, the meandering correction roller 12 is deflected in the direction of arrow C in FIG. As a result, the belt photoreceptor 1 is attached to the front plate SB1.
Diagonal in direction.

Further, when the step motor 36 operates in the CCV (counterclockwise) direction, the slider 63 moves upward in FIG. 9, thereby deflecting the meandering correction roller 12 in the direction of the arrow in FIG. 3. As a result, the belt photoreceptor 1 is attached to the rear □ plate S.
Diagonal in 82 directions.

By the way, when the deflection plate 37 is rotated, the shaft 48 is moved to the boss 49.
attempts to rotate using the self-aligning bearing 55 as a fulcrum. However, since the movement direction of the boss 5o that receives the shaft 48 is regulated by the front and rear side plates, the shaft 48 cannot move circularly. Therefore, in this mechanism, when moving in the directions of arrows C and D as shown in FIG. is absorbed.

In this figure, arrows C and D indicate the same direction as in FIG. 2. Further, the distance 1iL1 indicates the axial length of the meandering correction roller 12 when it is not deflected, and the distance L2 indicates the axial length of the meandering correction roller 12 when it is deflected to the limit point. indicates the distance to the limit point at which the axis 48 is deflected in the direction. Naturally, the distance L2 is Ll
The shaft 48 is larger than the self-aligning bearing 55 by that difference.
sliding inside.

FIG. 10 shows an example of the control section.

In the figure, reference numeral 70 denotes a main body control section which is composed of a microcomputer or the like and controls various parts 71 of the main body (not shown) of the copying machine in a predetermined manner. The driver 72
The step motor 36 is controlled via the driver 73 and the step motor 36 is driven via the driver 73.

75 is a pulse encoder attached to the main motor 74, and the pulse signal [EP outputted by the pulse encoder 75 is applied to the main body control section 70 and used as a reference clock signal for process management.

Furthermore, output signals from the photosensors Sl and S2 are also applied to the main body control section 70.

Next, an overview of the control method for meandering correction will be explained.

First, as an initial control, when the photo sensor turns on for the first time after driving the belt photoreceptor 1-, the meandering correction roller 12
is deflected in the correction direction by a predetermined amount from the reference position.

When the photo sensor on the opposite side is then turned on, the meandering correction roller 12 is deflected in the correction direction by twice the predetermined amount.

Then, the moving speed of the belt photoreceptor 1 in the width direction during the first deflection (hereinafter referred to as the shifting speed) and the shifting speed during the second deflection are measured, and from these speed differences, Pel 1 to
Knowing the meandering tendency of the photoreceptor 1, a rough initial setting of the deflection amount and deflection position of the meander correction roller 12 is performed to cancel this meandering tendency.

After this initial control, the amount of deflection of the meander correction roller 12 is gradually reduced each time the photosensor is turned on, and the amount of deflection is corrected so that the left and right deviation speeds are equal, thereby causing the deviation of the belt photoreceptor 1. Gradually bring the speed closer to "0".

In addition, for example, if the belt photoreceptor 1 with a large circumferential length difference is
The amount of deflection between Sasuke and Mikioka Yafurou due to their hatred for the 12th season becomes significantly large. In this case, the tension applied to the belt photoreceptor 1 by the meandering correction roller 12 becomes significantly uneven in the width direction, which may cause the belt photoreceptor 1 to twitch or wave, resulting in inconvenience in image formation. . Therefore, in this embodiment, it is detected as an abnormality that the deflection position of the meandering correction roller 12 exceeds an appropriate range, and predetermined abnormality processing, such as stopping the copying machine, is executed.

Note that in this embodiment, the photosensors SL and S2 are arranged at fixed positions with respect to the belt photoreceptor 1;
The shifting speed is determined based on the number of pulse signals IEP obtained from when one photosensor turns off (effectively) until another photosensor turns on (effectively).

That is, when the number of first pulse signals EP obtained during that period is large, the shift speed is small, and when the number of pulse signals BP is small, the shift speed is high.

FIG. 11 shows a specific example of the meandering correction control executed by the main body control section 70 in this embodiment. This control is executed immediately when the copying machine is powered on.

First, the main body control section 70 includes a counter CP for holding the count value of the pulse signal BP, control data CD for controlling the number of drive pulses of the step motor 36, a variable CΔ for storing the previous deflection amount in a different direction, A counter CC for holding the number of executions of this control, a correction value CDb for control 1 to roll data CD, variables RA and RB for storing the shifting speed in different directions, and a variable that stores the difference between the variables RA and RB. R5 and other work areas necessary for control, and for example, the variable RC for storing the deflection position of the meandering correction roller is preset, such as the process of storing data corresponding to the reference position. Initialization processing consisting of processing to reset the initial data in a predetermined variable area, etc. is carried out, and the copying process is started (
Processing 101).

Next, flags FSI and FS2 are set to keep the photosensors Sl and S2 on, respectively, a flag FMCD is set to keep the control state in which the step motor 36 is controlled at least once, and other necessary controls. The flag is reset to 1. Therefore, the main motor 74 is activated and the belt photoreceptor 1 is driven in the state immediately after the start of control.

Since the meandering correction roller 12 is controlled to the reference position where the reference sensor 35 is turned on, the photosensors SL and S2 are both turned off, and the flag FMCD is set to reset 1, judgments 103, 104 and 105 are all made. The result is NO.

In this state, the belt photoreceptor 1 begins to meander gradually toward either end depending on the initial state of the belt photoreceptor 1- at that time. For example, if the belt photoreceptor 1 snakes in the direction of the front plate SB1 and the photosensor S1 is turned on, the flag FSI is set and the result of determination 103 becomes NO.

At this time, since the flag FMCD is in a reset state, the result of judgment 106 is NO, and the main body control unit 70 sets the maximum value CD + n a x of the deflection amount of the meandering correction roller 12 in the control data CD and variable CA (process 107 ).

Note that this maximum value CD nax is set corresponding to an amount of deflection from the reference position that does not cause twitching or corrugations on the belt photoreceptor 1.

Next, process 108 is executed to download the control data CD.
Update the variable RC. At this time, since the flag F is set to Sera 1-, the Controller 1 Serol data CD and the variable R
Update variable 1jC with the added value of C.

This updated variable RC is set to limit data LDI, which is set slightly smaller than the value obtained by subtracting the maximum value CD+nax from the data corresponding to the reference position, and slightly larger than the value obtained by adding the maximum value CDmax to the data corresponding to the reference position. - Judgment 1 to determine whether or not it is within the range of the set limit data LD2.
If the result of this judgment 109 is NO, a predetermined abnormality process 110 is executed, and the meandering correction process of the main body control section 70 is completed.

In this case, the value of variable RC is within the range of limit data LDI and LD2, so the result of judgment 109 is '/ES, which is 1.
The main body control unit 70 executes processing 111.

In this process 111, since the flag FSI is set, the control data CD is sent to the driver 7 along with a direction instruction signal for rotating the step motor controller 36 in the ccv direction.
3 to drive the step motor 36.

As a result, the meandering correction roller 12 is deflected in the direction by a preset maximum amount, and the belt photoreceptor 1 changes its direction toward the rear side plate SB2 and starts meandering.

In this way, since the step motor 36 was controlled once,
The main body control unit 7o sets the flag FMCD and increments the counter cc (process 112).

When the photoreceptor 1 starts meandering toward the bell 1 in the opposite direction (that is, toward the rear plate SB2) and the photosensor s1 is turned off, the flag FSI is reset, and both photosensors s1 and S2 are turned off, making judgments 103 and 104. Both results are NOl.Furthermore, since the flag FMCD is set, the result of judgment 105 is VES.

Therefore, while this state continues, the main body control unit 7o
Set the count value of the pulse signal EP to the counter cP (
Along with process 113), control data CD to be output next is calculated (process 114).

The formula for calculating this control data CD is % Formula % CD = CDa + CA -- (T) However, CDa is the effective deflection amount in the correction direction, and is expressed by the following formula (II).

CDa=-a-RA+cDmax-(II) where,
a is a coefficient for converting the count value of the pulse signal EP into a roll amount of the controller 1 of the step motor 36, and is a positive real number smaller than 1.

In this case, the value of the variable CA is the maximum value CDmax, and the value of the variable RA is O, so the value of the control data CD to be output next will be twice the maximum value CDmax.

By the way, the above formula (I) means that the meandering correction roller 12 is once returned to its original position and then deflected to the reflection side.

That is, in the present invention, while the bell 1 and the photoreceptor 1 are meandering left and right alternately, the speed of the shift is gradually reduced. Then, the meandering correction roller 12 is deflected in the correction direction by a deflection amount (CDa) smaller than the previous deflection amount of the meandering correction roller 12 in the same direction.

Now, as the meandering of the belt photoreceptor 1 progresses, the hook 1-sensor S
2 is turned on, flag FS2 is set and judgment 104 is made.
The result is YES. At this time, the flag FMCD is set, so the result of judgment 106 is YES.
The main body control unit 70 executes process 15.

In this process 115, the value of variable RA is assigned to variable RB, the value of counter CP is assigned to variable RA, and,
Reset the counter CP.

Therefore, a value corresponding to the shifting speed of the belt photoreceptor 1 at this time is stored in the variable RA, and a value corresponding to the shifting speed of the belt photoreceptor 1 at this time is stored in the variable RB.
A value corresponding to the moving speed of the Pel 1 to the photoreceptor 1 in the opposite direction is stored.

However, in this case, since it is in the initial state, the value of variable RA is 0 before processing 115 is executed, and therefore the value of variable RB is 0.

The next judgment 116 after the process 115 is that the value of the counter CC is 1.
Therefore, the result is NO, and the main body control unit 70 performs processing 1.
Execute 08. In this case, since the flag FS2 is set, the variable RC is updated to the value obtained by subtracting the control data CD from the variable RC.

At this time, the variable RC is calculated from the value obtained by adding the maximum value CDmay to the data corresponding to the reference position, to 2 of the maximum value CDmay.
Since it is the value obtained by subtracting the double value, it is equal to the value obtained by subtracting the maximum value CDmax from the data corresponding to the reference position.

Therefore, the result of judgment 109 is YES, and the control data CD at this point is output to the driver 73 as is in process 111. However, in this case, since the flag FS2 is set, a direction instruction signal for rotating the step motor 36 in the CW force direction is output.

Thereafter, process 112 is executed and the counter CC is incremented.

As a result, the meandering correction roller 12 is deflected in the direction C by twice the previous deflection amount. This is the meandering correction roller 12.
This is equivalent to deflecting from the reference position in direction C by a preset maximum amount.

As a result, the photoreceptor 1 begins to meander toward the front plate SB1 toward the bell 1.

Then, when the photosensor S2 is turned off, the flag FS2 is reset and the results of the first judgments 103 and 104 are NO, and the result of the judgment 105 is YES as described above, so the processing is continued until the photosensor S1 is turned on next time. 113°1
14 is executed repeatedly.

The part up to this point corresponds to the initial control described above.

Now, next time the photosensor S1 is turned on, judgment 103
．． 106 and processing 115 are executed sequentially, and since the value of the counter CC is 2 at this time, the result of judgment 1l-fi is YE.
S, and the main body control unit 70 executes process 117.

In this process 117, first, a difference R5 between variables RA and RB is determined, and a correction value CDb of the control data is calculated from this difference R5 according to the following equation (■).

CDb=b-R5...(Ill) However, b is a constant.

As mentioned above, in this case, the variable RA contains the number of pulse signals EP generated between hook 1 and sensor S2 turning off until Sl turns on, and the variable RB contains the number of pulse signals EP generated before the photo sensor S1. The number of pulse signals EP generated between when S2 is turned off and when S2 is turned on is stored.

Therefore, this difference R5 is the difference between the deviation speed toward the front side plate SB1 and the deviation speed toward the rear side plate SB2 when the meandering correction roller 12 is deflected from the reference position by the same amount in the directions C and D.
In other words, it corresponds to the meandering tendency of the Pel 1 to the Photoreceptor 1.

Therefore, in judgment 118, it is determined which side has a higher deviation speed, and if the result of judgment 118 is YES, the deviation speed in the next meandering direction is small, so the correction value CDb is added to the control data CD to adjust the deflection amount. If the result of the judgment 118 is NO, the deviation speed in the next meandering direction is large, so the correction value cob is subtracted from the control data CD to reduce the deflection amount (process 120).

As a result, the meandering correction roller 12 is deflected more largely in the direction of suppressing the meandering tendency based mainly on the difference in circumferential length of the belt photoreceptor 10, and the standard of the deflection position is almost set, and the meandering correction roller 12 is deflected toward each end. The approaching speeds of the two are almost the same. - After this, among the processes described above, the processes after the initial control are repeatedly executed. Therefore, the control data CD is sequentially set smaller in step 114, and step 117. Judgment 118. Processing 119,
At step 120, the control data CD is corrected so that the left and right shifting speeds of the belt photoreceptor 1 are equal.

Further, in the process 1082 judgment 109, it is determined whether the deflection position of the meandering correction roller 12 is within an appropriate range.
If this range is exceeded, @1llO is executed for each error.

As a result, the shifting speed of the belt photoreceptor 1 gradually decreases, and disturbances in the copied image due to the meandering phenomenon are suppressed.

In the above explanation, one end of the shaft of the meandering correction roller is supported and the other end is deflected by a step motor or the like.
The deflecting means is not limited to this. Any device may be used as long as it has the function of being able to deflect the meandering correction roller in two directions and controlling the amount of deflection.

[Effects] As explained above, according to the present invention, the amount of deflection of the meandering correction roller is maximized during the initial control, and thereafter the amount of deflection gradually decreases, so that the swinging speed of the endless belt in the width direction can be kept small. Can be done.

Furthermore, since an abnormality is detected when the deflection position of the meandering correction roller exceeds a predetermined range, there is an advantage that problems such as damage to the endless belt when using an endless belt with a large difference in circumferential length can be prevented.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an example of an endless belt drive device, Fig. 2 is a front view showing an embodiment of the present invention, Fig. 3 is a partial view showing the peripheral structure of the sensor section, and Fig. 4 is the sensor. FIG. 5 is a partial perspective view showing the positional relationship between the sensor and the belt photoreceptor, FIG. 6 is a perspective view showing the drive section of the meandering correction roller, and FIG. 7 8 is a perspective view showing the deflection mechanism, FIG. 9 is a front view showing the deflection mode of the meandering correction roller, and FIG. 10 is the control system. The block diagram, FIG. 11, is a flowchart showing the control means. 1... Pel 1 to photoreceptor, 12... Meandering correction roller,
13.14...Followed roller, 24...Sensor part, 3
6... Step roller, 37... Deflection plate, 38.4
5... Roller support plate, 46... Shaft, 47... Bearing, 49, 50... Boss, 52... Pin, 55.
56... Self-aligning bearing, 60.61... Miter gear, 62... Lead screw, 63... Slider, 7
0... Main body control unit, 73... Driver, 74...
・Main motor, 75...Pulse encoder, Sl,
S2...Photo sensor. Figure 5 Figure 7 Figure 8 Figure 1 70 Figure Procedure Amendment Band (Spontaneous) April 9, 1980 Dear Commissioner of the Japan Patent Office 1, Indication of the case 1981 Patent Application No. 26144 2, Name of the invention Endless belt drive Device 3, Relationship with the case of the person making the amendment Patent applicant address 1-3-6 Nakamagome, Ota-ku, Tokyo Name (67U
Ricoh Co., Ltd. Representative Hama 1) Hiro 4, Agent 105 Address 1-18-11 Nishi-Shinbashi, Minato-ku, Tokyo Column 6 of the detailed description of the invention in the specification, Contents of the amendment Page 16 of the specification of the present application On line 14, “The result of judgment 103 is N.
OJ is corrected to ``The result of judgment 103 is YESJ.'' 62

Claims (1)

[Claims] In an endless belt drive device in which at least one of a plurality of rollers that support and drive an endless belt under tension acts as a meandering correction roller that corrects meandering of the endless belt, a deflection means that deflects an axis of the meandering correction roller; A control means for controlling the direction and amount of deflection of the deflection means, a speed detection means for detecting the speed at which the endless belt shifts in the width direction, and a speed correction value calculated based on the speed at which the endless belt shifts in the width direction. Deflection amount calculation means for providing a corresponding deflection amount to the control means; and abnormality detection for calculating the deflection position of the meandering correction roller based on the deflection amount and detecting as an abnormality that the deflection position exceeds a predetermined range. An endless belt drive device characterized by comprising means.