the present inventors first made various experiments to know where matters stand now . fig4 shows the relationship between the time ( hr ) in which a brush 13 was left as it was in a state of stoppage and the velocity regulation (%) of a photoreceptor due to the brush 13 . in fig4 a represents the case of using a brush in which the material of hairs thereof was polypropylene , the outer diameter of the brush was 18 mm , and the thickness and density of the hairs were 17 deniers and 60 , 000 / in 2 respectively ; b represents the case of using a brush which was the same as the above - mentioned brush except that the hairs of which were inclined ; and c represents the case of using a brush in which the material of hairs was copolymer of acrylic resin and vinyl chloride , the outer diameter of the brush was 18 mm , and the thickness and density of the hairs were 20 deniers and 60 , 000 / in 2 respectively . as understood from this drawing , it was found that the velocity regulation of the photoreceptor due to the brush became larger as the standing time got longer , and in the case a the velocity regulation went over a target value ( shown by the one - dot chain line ) after about one - hour standing . fig5 shows the relationship between the number of copies and the velocity regulation of a photoreceptor in the case where the working of copying was performed after 1 . 5 - hours . in fig5 d represents the case of using a brush in which the material of hairs was polypropylene , the outer diameter of the brush was 18 mm , and the thickness and density of the hairs were 17 deniers and 60 , 000 / in 2 respectively . in this case , the regulation was large when the number of copies was small , and the regulation had saturated since the number of copies was over 25k ( 25 , 000 ). fig6 shows the relationship between the velocity regulation of the photoreceptor and the time of rotation when a brush which had been left as it was for 12 hours was rotated again . in fig6 e represents the case of using a brush in which the material of hairs was polypropylene , the outer diameter of the brush was 18 mm , and the thickness and density of the hairs were 17 deniers and 60 , 000 / in 2 respectively ; f represents the case of using a brush in which the material of hairs was polypropylene , the outer diameter of the brush was 19 mm , and the thickness and density of the hairs were 8 . 5 deniers and 60 , 000 / in 2 respectively ; g represents the case of using a brush in which the material of hairs was polypropylene , the outer diameter of the brush was 18 mm , and the thickness and density of the hairs were 17 deniers and 60 , 000 / in 2 respectively ; and h represents the case of using a brush in which the material of hairs was copolymer of acrylic resin and vinyl chloride , the outer diameter of the brush was 18 mm , and the thickness and density of the hairs were 20 deniers and 60 , 000 / in 2 respectively . as a result of these experiments shown in fig6 it was found that in the case e , if the brush was left as it was for 12 hours ( one night ) after it was stopped , it was necessary to make the brush race for about 2 . 5 minutes to obtain the velocity regulation of the photoreceptor which was not larger than the target value . further , as a result of the above - mentioned experiments , it was found that in the case e , it was necessary to make the brush race for at least 2 . 5 minutes within two hours in a copying rest period ( stand - by period ). the method according to the present invention has been attained on the basis of the results of the above - mentioned respective experiments , in which a brush is made to race together with a photoreceptor ( 1 ) in a warming - up time ( according to the first aspect of the invention ), ( 2 ) in a stand - by time ( according to the second aspect of the invention ), and ( 3 ) at a time of exchanging a cartridge constituted by a photoreceptor and a cleaning device ( according to the third aspect of the invention ). preferred embodiments according to the various aspects of the invention will be described hereunder . in these embodiments , a brush in was used which the material of hairs was polypropylene , the outer diameter of the brush was 19 mm , and the thickness and density of the hairs were 8 . 5 deniers and 60 , 000 / in 2 respectively . fig1 shows a control circuit according to the present invention . in the control circuit , a control device 20 is provided with a central processing unit ( cpu ) 23 , a read - only memory ( rom ) 22 having a predetermined copying machine operating program stored therein , an input interface 21 for receiving signals from sensors disposed in various portions in the copying machine , a random access memory ( ram ) 24 for temporarily storing signals supplied from the input interface 21 or operation results of the cpu 23 , and an output interface 25 for outputting signals for operating copying constituent elements disposed in various respective portions of the copying machine . the cpu 23 , the rom 22 , the input interface 21 , the ram 24 and the output interface 25 are connected to each other through a data base so that they can exchange communication of data with each other in accordance with commands from the cpu 23 . as shown in the flow chart which will be described later , the control device 20 controls the copying machine . this control device 20 is connected , through a connector 28 , to a print cartridge substrate 26 disposed in a print cartridge which has been described in fig7 . in this print cartridge substrate 26 , provided is an electrically erasable programmable read only memory ( eeprom ) 27 carrying data showing the life of the print cartridge , data showing an unused print cartridge necessary for the present invention , and other data which have been stored therein . the input interface 21 is supplied with a signal showing that a main switch ( not shown ) is turned on , a signal showing that a front cover ( not shown ) provided in the operational front side of the copying machine is closed , a temperature sensor signal from a sensor ( not shown ) for detecting the temperature of the fusing roll of the fusing device 11 shown in fig7 a copying signal showing that a copying operation starts , and other signals from various other sensors and from an operation panel ( not shown ) disposed in the copying machine . from the output interface 25 , control signals are output for controlling a main motor driving circuit 29 for driving a main motor 30 of the copying machine and other of the copying machine constituent members of the copying machine such as a paper carrying path driving motor , a clutch indicator , and so on . the main motor 30 is connected to the main motor driving circuit 29 so that the main motor 30 rotates not only the photoreceptor 5 but also the brush 13 in the cleaning device 12 through a gear and a timing belt . in addition , the rotational power of this main motor 30 is transmitted to the fusing device 11 . the present invention will be described more in detail separately for various conditions . if a main switch ( not shown ) which is a power source switch of the copying machine is turned on , the temperature of the fusing device 11 is made high in the state of stoppage of the main motor 30 , that is , in the state the fusing device 11 is not rotated . this is because the thermal efficiency of the fusing device improves if the device is not rotated . if the power source switch , that is , the main switch ( not - shown ), is turned on to supply power to respective electric constituent parts in the copying machine , a main - switch - on signal indicating the on - state of the main switch is supplied to the control device 20 shown in fig1 to start the control on the copying machine . a program is started by this main - switch - on signal . after the power source is turned on , first , the program control heats a heater of the fusing device 11 shown in fig7 ( step 43 ). the period until the temperature of the fusing device 11 reaches a predetermined value ( about 200 ° c .) is called a warming - up time . in this period , the control device 20 performs the control , which will be described thereafter , to rotate the main motor 30 . at a point of time after a period of time in which no trouble is caused in warming - up the fusing device 11 , for example , after a lapse of about 130 sec , a racing cycle is started so that the main motor 30 is driven and the photoreceptor 5 and the brush 13 of the cleaning device 12 are made to race ( step 44 ). this racing is continued for a time not longer than 30 sec . at this time , an erasure lamp is turned on at the same time as the above - mentioned main motor 30 is driven , then a charge corotron and a transfer corotron are controlled , and after that , the developing device 6 is controlled , while a very small quantity of toner is supplied to the photoreceptor 5 in this racing cycle . fig3 shows the timing at this time . in the above - mentioned racing cycle , when the fusing device 11 becomes about 200 ° c ., a cycle - out mode ( erasure or static elimination cycle ) is started ( step 45 ). this cycle - out mode is performed for about 3 , 000 msec , that is , only the time of one rotation of the photoreceptor . in this warming - up time , if a copying signal is supplied during the racing cycle or during the cycle - out mode , a copying mode is started after the cycle - out mode is terminated . in a period before the racing cycle starts after the main switch is turned on ( not longer than 130 sec ), a normal operation is performed . in the stand - by time , in the state where the main switch has been turned on , the main motor is driven for about 1 , 000 msec , preferably for 200 msec , at intervals of 30 minutes to rotate the photoreceptor 5 and the brush 13 so as to change the position of the brush 13 at which the brush 13 contacts with the photoreceptor 5 . ( i ) racing is performed at intervals of 30 minutes in the case where no copying signal is supplied after the main switch is turned on ; ( ii ) racing is performed at intervals of 30 minutes after the cycle - out when copying is finished ; and ( iii ) racing is performed at intervals of 30 minutes if no copying signal is supplied after racing is executed . fig2 shows a flow chart of the racing rotation operation in the above - mentioned stand - by time . the control in the stand - by time will be described with reference to the flow chart . if the main switch is turned on ( step 51 ), a judgement is made as to whether there is a copying start signal or not ( step 52 ). if there is no copying start signal , the operation advances through the path of no and a judgment is made as to whether 30 minutes have passed or not by use of a timer in the control device 20 ( step 53 ). if 30 minutes has not yet passed , the detection of existence of a copying start signal is , continued in step 52 . if 30 minutes have passed in step 54 , the operation advances to step 53 in which the brush 13 is made to race . the time for this racing is about 1 , 000 msec as has been described . as has been described , in the time of stoppage of copying , racing is performed for 1 , 000 msec at intervals of 30 minutes . if a copying start signal is supplied in step 52 , a copying operation is performed to make up a copy ( step 55 ). if the copying operation is finished and the cycle - out period is over , a counting operation is made as to whether 30 minutes has passed or not ( step 56 ). if 30 minutes have passed , the brush 13 is made to race for 1 , 000 msec ( step 57 ). ( 3 ) at the time of exchange of a print cartridge constituted by a photoreceptor and a cleaning device the exchange of a print cartridge is detected by detecting the fact that the number of copies performed by this print cartridge is in a range between 0 and 1 , 000 , and after the main switch is turned on , the same operation as in the above - mentioned warming - up time is executed , that is , a racing mode is executed for 2 . 5 to 3 . 5 minutes after 130 sec have passed after the main switch is turned on , and thereafter a cycle - out mode is started . fig1 also shows a flow chart of the above - mentioned racing mode at the time of exchange of the print cartridge . that is , if the power source switch is turned on , the control device 20 shown in fig1 operates to start execution of a program . the control device 20 determines whether the front cover is closed or not ( step 31 ), and if the cover is closed , the control device 20 performs self - diagnosis ( steps 33 and 34 ). if the cover is not closed , the main motor 30 is stopped ( step 32 ). thereafter , the control device 20 makes access to an address in the eeprom 27 shown in fig1 provided in the print cartridge , in which a state signal indicating if this print cartridge has been used or not is stored ( step 35 ). this address carries predetermined data ( for example , the number ff expressed by the hexadecimal number system in the embodiment ) which is written when the print cartridge is produced in a factory . therefore , this data is a value showing that the print cartridge has never been used . next , a judgment is made as to whether the contents in the eeprom 27 indicate the value ff or not ( step 36 ), and if not this value , the main motor 30 is stopped ( step 37 ). if the eeprom 27 gives the value ff , a 2 . 5 - minute timer included in the control device 20 is started ( step 38 ), and a main motor driving command is generated so as to rotate the main motor 30 so that the brush 13 coupled with this motor 30 is rotated ( step 39 ). then , other copying machine constituent members are driven ( step 40 ). if the 2 . 5 - minute timer has counted 2 . 5 minutes and indicates the time is over , the main motor 30 is stopped ( steps 41 and 42 ). if all the above - mentioned steps and steps 43 , 46 and 47 are finished , the copying machine is put in a copying ready state so as to enable copying ( step 48 ). here , a ros ( raster output scanner ) motor for driving a polygon mirror which scans a laser beam is driven in step 46 , and a communication with an image processing device which outputs data to be recorded is performed in step 47 . if a copying operation is started thereafter to make up a copy , the above - mentioned data ff in the eeprom 27 is changed to another value . thus , it is possible to determine whether the print cartridge is a new one or not . according to the present invention , without changing an internal structure of a copying machine , it is possible to correct the transformation of hairs of the brush caused by stoppage of the copying machine by properly arranging the electric timing , that is , by making a photoreceptor and a brush of a cleaning device race for a predetermined time in the stand - by time and before a copying operation , and it is possible to solve a banding problem caused by the falling of the hairs of the brush only by a simple improvement , that is , only by changing software . further , it is possible to maintain the performance of scraping toner or talc from the surface of the photoreceptor in the same manner as in the convention case .