Automatic sheet feeder and scan apparatus with assemblies for transporting sheet at different speeds

Abstract

An automatic sheet feeder includes a sheet passageway, an opening formed in the sheet passageway and a sheet transporting mechanism. The sheet transporting mechanism transports a sheet through the sheet passageway. The sheet transporting mechanism includes a first transporting assembly and a second transporting assembly, which is disposed downstream of the first transporting assembly. The first transporting assembly transports the sheet to the opening at a first speed, and the second transporting assembly transports the sheet away from the opening at a second speed higher than the first speed. A scan apparatus using the automatic sheet feeder is also disclosed.

1 . An automatic sheet feeder, comprising:
 a sheet passageway;   an opening formed in the sheet passageway; and   a sheet transporting mechanism for transporting a sheet through the sheet passageway, the sheet transporting mechanism comprising:
 a first transporting assembly; and 
 a second transporting assembly disposed downstream of the first transporting assembly, wherein: 
 the first transporting assembly transports the sheet to the opening at a first speed; and 
 the second transporting assembly transports the sheet away from the opening at a second speed higher than the first speed. 
   
     
     
         2 . The automatic sheet feeder according to  claim 1 , further comprising a feeding tray for supporting the sheet, wherein the first transporting assembly transports the sheet from the feeding tray into the sheet passageway. 
     
     
         3 . The automatic sheet feeder according to  claim 2 , wherein:
 the first transporting assembly comprises a first roller and a frictional element located opposite the first roller for separating the sheet from a stack of sheets and transporting the sheet into the sheet passageway.   
     
     
         4 . The automatic sheet feeder according to  claim 1 , wherein the first transporting assembly comprises a first roller, disposed in the sheet passageway, for transporting the sheet to the opening. 
     
     
         5 . The automatic sheet feeder according to  claim 4 , wherein the second transporting assembly comprises a second roller, disposed in the sheet passageway, for transporting the sheet away from the opening and out of the sheet passageway. 
     
     
         6 . The automatic sheet feeder according to  claim 5 , further comprising a power source, wherein the first roller and the second roller are driven by the power source. 
     
     
         7 . The automatic sheet feeder according to  claim 5 , wherein outer diameters of the first roller and the second roller are equal. 
     
     
         8 . The automatic sheet feeder according to  claim 5 , wherein outer diameters of the first roller and the second roller are unequal. 
     
     
         9 . The automatic sheet feeder according to  claim 1 , further comprising:
 a guiding element, disposed downstream of the first transporting assembly, for guiding the sheet to the second transporting assembly.   
     
     
         10 . A scan apparatus, comprising:
 an automatic sheet feeder comprising:   a sheet passageway;   an image-processing area; and   a sheet transporting mechanism for sequentially transporting a first sheet and a second sheet through the sheet passageway, the sheet transporting mechanism comprising:
 a first transporting assembly; and 
 a second transporting assembly disposed downstream of the first transporting assembly, wherein: 
 the first transporting assembly transports the first sheet and the second sheet to the image-processing area at a first speed, and the second transporting assembly transports the first sheet and the second sheet away from the image-processing area at a second speed higher than the first speed; and 
   a scan module for continuously scanning the first sheet and the second sheet within the image-processing area and generating a continuous image, which comprises a first sheet image corresponding to the first sheet, a second sheet image corresponding to the second sheet and a gap image corresponding to a gap between the first sheet and the second sheet.   
     
     
         11 . The scan apparatus according to  claim 10 , further comprising a feeding tray for supporting the first sheet and the second sheet, and the first transporting assembly sequentially feeds the first sheet and the second sheet from the feeding tray into the sheet passageway. 
     
     
         12 . The scan apparatus according to  claim 11 , wherein the first transporting assembly comprises a first roller and a frictional element located opposite the first roller for separating the first sheet from the second sheet and sequentially transporting the first sheet and the second sheet into the sheet passageway. 
     
     
         13 . The scan apparatus according to  claim 10 , wherein the first transporting assembly comprises a first roller, disposed in the sheet passageway, for transporting the first sheet and the second sheet sequentially to the image-processing area. 
     
     
         14 . The scan apparatus according to  claim 13 , wherein the second transporting assembly comprises a second roller, disposed in the sheet passageway, for transporting the first sheet and the second sheet sequentially away from the image-processing area and out of the sheet passageway. 
     
     
         15 . The scan apparatus according to  claim 14 , further comprising a power source, wherein the first roller and the second roller are driven by the power source. 
     
     
         16 . The scan apparatus according to  claim 14 , wherein outer diameters of the first roller and the second roller are equal. 
     
     
         17 . The scan apparatus according to  claim 14 , wherein outer diameters of the first roller and the second roller are unequal. 
     
     
         18 . The scan apparatus according to  claim 10 , further comprising:
 a guiding element, disposed downstream of the first transporting assembly, for guiding the first sheet and the second sheet sequentially to the second transporting assembly.   
     
     
         19 . The scan apparatus according to  claim 10 , further comprising:
 an image-processing device, electrically connected to the scan module, for receiving and processing the continuous image, wherein the image-processing device divides the continuous image into the first sheet image and the second sheet image according to the gap image.   
     
     
         20 . The scan apparatus according to  claim 10 , wherein the scan apparatus outputs the continuous image to an external image-processing device electrically connected to the scan apparatus, wherein the external image-processing device processes the continuous image and divides the continuous image into the first sheet image and the second sheet image according to the gap image.