Image forming apparatus

Abstract

An image forming apparatus includes: a sheet transport mechanism including: a sheet feeding unit; an attitude correction unit that corrects an attitude of a sheet; and a drive source; a first actuator that operates upon receipt of supply of power from a power source, when a sheet feeding command is issued, and transmits power of the drive source to the sheet feeding unit to commence driving of the sheet feeding unit; a second actuator that operates upon receipt of power from the power source and controls the attitude correction unit into an attitude correctable state, when a transported sheet has approached the attitude correction unit; and a control unit that determines an operation start timing of the first actuator, operation of the first actuator, which transports the next sheet after transport of one sheet, starting after operation of the second actuator for the one sheet has been completed.

1 . An image forming apparatus comprising: 
 a sheet transport mechanism including: 
 a sheet feeding unit that feeds a sheet from a sheet feeding cassette;  
 an attitude correction unit that corrects an attitude of the sheet fed from the sheet feeding unit; and  
 a drive source that drives the sheet feeding unit and the attitude correction unit;  
   a first actuator that operates upon receipt of supply of power from a power source, when a sheet feeding command is issued, and transmits power of the drive source to the sheet feeding unit to commence driving of the sheet feeding unit;    a second actuator that operates upon receipt of power from the power source and controls the attitude correction unit into an attitude correctable state, when a transported sheet has approached the attitude correction unit; and    a control unit that determines an operation start timing of the first actuator, operation of the first actuator, which transports the next sheet after transport of one sheet, starting after operation of the second actuator for the one sheet has been completed.    
   
   
       2 . The image forming apparatus according to  claim 1 , further comprising: 
 a storage unit that stores an operation status of the second actuator, wherein    the control unit determines whether or not operation of the second actuator has been completed based on the operation status of the second actuator.    
   
   
       3 . The image forming apparatus according to  claim 2 , further comprising: 
 a detection sensor that detects an approach of a sheet to the attitude correction unit, wherein    operation of the second actuator is controlled so as to stop after elapse of a predetermined period of time since start of operation;    the storage unit stores a time when the detection sensor detects an approach of a sheet; and    the control unit uses the time when the detection sensor detects an approach of a sheet as a time when the second actuator is to start operation, and the control unit determines whether or not operation of the second actuator has been completed based on elapse of the predetermined period of time since the operation start time of the second actuator stored in the storage unit.    
   
   
       4 . The image forming apparatus according to  claim 2 , wherein 
 data pertaining to an operating status of the second actuator with regard to one sheet are erased before the first actuator starts operation to transport the next sheet; and    when operation of the second actuator is again started in association with transport of the next sheet, an operating status of the second actuator is stored in the storage unit.    
   
   
       5 . The image forming apparatus according to  claim 1 , further comprising 
 a relay roller that is rotated at all times, wherein:    the relay roller is interposed between the sheet feeding unit and the attitude correction unit; and    when transport of a sheet from the sheet feeding unit has once been started, the sheet is transported up to the attitude correction unit without being stopped in a sheet transport path.    
   
   
       6 . The image forming apparatus according to  claim 1 , further comprising 
 a transmission gear that transmits power, wherein:    the sheet feeding unit and the attitude correction unit are connected to the drive source by the transmission gear; and    the sheet feeding unit and the attitude correction unit rotate upon receipt of a supply of driving force from the drive source.    
   
   
       7 . The image forming apparatus according to  claim 1 , further comprising: 
 an operation interval determination unit that determines an operation interval time of the first actuator such that the number of operations of the first actuator per unit time does not exceed a preset number, wherein    the control unit determines the operation start timing of the first actuator to start operation of the first actuator with regard to the next sheet after operation of the second actuator for the one sheet has been completed and the operation interval time has elapsed since the start of operation of the first actuator for the one sheet.    
   
   
       8 . An image forming apparatus comprising: 
 a sheet transport mechanism including: 
 a sheet feeding unit that feeds a sheet from a sheet feeding cassette;  
 an attitude correction unit that corrects an attitude of the sheet fed from the sheet feeding unit; and  
 a drive source that drives the sheet feeding unit and the attitude correction unit;  
   a first actuator that operates upon receipt of supply of power from a power source every time a sheet feeding command is issued and transmits power of the drive source to the sheet feeding unit to commence driving of the sheet feeding unit;    a second actuator that operates upon receipt of power from the power source, when a transported sheet has approached the attitude correction unit, to control the attitude correction unit into an attitude correctable state; and    an operation interval determination unit that determining an operation interval time of the first actuator such that the number of operations of the first actuator per unit time does not exceed a preset number; and    a control unit that determines operation start timing of the first actuator, operation of the first actuator for the next sheet starting after the operation interval time has elapsed since the start of operation of the first actuator for one sheet.    
   
   
       9 . The image forming apparatus according to  claim 1 , wherein 
 the sheet feeding unit is a sheet feeding roller;    the attitude correction unit is registration rollers; and    the drive source is a main motor.    
   
   
       10 . The image forming apparatus according to  claim 9 , wherein 
 roller shafts of the sheet feeding roller and the registration rollers are connected to the main motor by a transmission gear; and    the sheet feeding roller and the registration rollers rotate upon receipt of a supply of driving force from the main motor.