Conveyance device, printing device, and conveyance method

Abstract

A conveyance device including an upstream roller that supplies a sheet medium to be processed to a conveyance path; a downstream roller that conveys the supplied medium to a processing position; and a control unit that controls driving the upstream roller and the downstream roller to convey the sheet medium at a constant speed. The control unit determines the starting time of the upstream roller and the downstream roller when starting the conveyance operation based on specific information about the upstream roller and the downstream roller in a previous conveyance operation.

1 . A conveyance device comprising:
 an upstream roller that supplies a sheet medium to be processed to a conveyance path;   a downstream roller that conveys the supplied medium to a processing position; and   a control unit that controls driving the upstream roller and the downstream roller to convey the sheet medium at a constant speed, and
 determines the starting time of the upstream roller and the downstream roller when starting the conveyance operation based on specific information about the upstream roller and the downstream roller in a previous conveyance operation. 
   
     
     
         2 . The conveyance device described in  claim 1 , wherein:
 the specific information is information about the behavior of the upstream roller and the downstream roller in the previous conveyance operation until reaching the constant speed.   
     
     
         3 . The conveyance device described in  claim 1 , wherein:
 the specific information is drive information at the constant speed of the upstream roller and the downstream roller in the previous conveyance operation.   
     
     
         4 . The conveyance device described in  claim 1 , wherein:
 determination of the starting time delays the starting time of the downstream roller relative to the upstream roller.   
     
     
         5 . The conveyance device described in  claim 2 , wherein:
 the information about the behavior until reaching the constant speed is the time from when the upstream roller and the downstream roller start until the constant speed is reached.   
     
     
         6 . The conveyance device described in  claim 2 , wherein:
 the information about the behavior until reaching the constant speed is the amount the sheet medium is respectively conveyed by the upstream roller and the downstream roller from when the upstream roller and the downstream roller start until the time required for the upstream roller to reach the constant speed after starting passes.   
     
     
         7 . The conveyance device described in  claim 3 , wherein:
 the drive information at the constant speed is information indicating the amount of power required to drive the upstream roller and the downstream roller.   
     
     
         8 . The conveyance device described in  claim 2 , wherein:
 information indicating the relationship between the information about the behavior until reaching the constant speed or the drive information at the constant speed, and the starting time, is stored in advance for different types of sheet media.   
     
     
         9 . The conveyance device described in  claim 3 , wherein:
 information indicating the relationship between the drive information at the constant speed and the starting time is stored in advance for different types of sheet media.   
     
     
         10 . The conveyance device described in  claim 1 , wherein:
 the sheet medium is supplied from a roll to the upstream roller.   
     
     
         11 . A printing device that comprises the conveyance device described in any of  claims 1  to  10 , and prints on the sheet medium at the processing position. 
     
     
         12 . A conveyance method of a conveyance device including an upstream roller that supplies a sheet medium to be processed to a conveyance path, a downstream roller that conveys the supplied medium to a processing position, and a control unit that controls driving the upstream roller and the downstream roller to convey the sheet medium at a constant speed, wherein:
 the control unit determines the starting time of the upstream roller and the downstream roller when starting the conveyance operation based on specific information about the upstream roller and the downstream roller in a previous conveyance operation.   
     
     
         13 . The conveyance method described in  claim 12 , wherein:
 the specific information is information about the behavior of the upstream roller and the downstream roller in the previous conveyance operation until reaching the constant speed.   
     
     
         14 . The conveyance method described in  claim 12 , wherein:
 the specific information is drive information at the constant speed of the upstream roller and the downstream roller in the previous conveyance operation.   
     
     
         15 . The conveyance method described in  claim 12 , wherein:
 determination of the starting time delays the starting time of the downstream roller relative to the upstream roller.   
     
     
         16 . The conveyance method described in  claim 13 , wherein:
 the information about the behavior until reaching the constant speed is the time from when the upstream roller and the downstream roller start until the constant speed is reached.   
     
     
         17 . The conveyance method described in  claim 13 , wherein:
 the information about the behavior until reaching the constant speed is the amount the sheet medium is respectively conveyed by the upstream roller and the downstream roller from when the upstream roller and the downstream roller start until the time required for the upstream roller to reach the constant speed after starting passes.   
     
     
         18 . The conveyance method described in  claim 14 , wherein:
 the drive information at the constant speed is information indicating the amount of power required to drive the upstream roller and the downstream roller.