Sheet discharge processing device

A sheet discharge processing device for sequentially discharging sheets, sent through image forming means for forming images on the sheets on the basis of image data, onto a discharge tray with image-bearing surfaces of the sheets facing up or down, comprising:

• first and second switchback convey paths being vertically arranged between an inlet path into which a sheet conveyed through said image forming means is conveyed and a discharge path for discharging a sheet onto the discharge tray, and said first and second switchback convey paths being adapted to reverse the front and back of sheets;
• a switching gate including a first reverse guide path for causing said first switchback convey path to communicate with the discharge path when said second switchback convey path communicates with said inlet path, a second reverse guide path for causing said second switchback convey path to communicate with the discharge path when said first switchback convey path communicates with said inlet path, and a straight guide path for causing said inlet path to communicate with the discharge path, and said switching gate being rotatably placed between said inlet path and the discharge path;
• first and second storing sections arranged at an upper end portion of said first switchback convey path and a lower end portion of said second switchback convey path to store sheets conveyed through said first and second switchback convey paths;
• and
• loop-like guide members, storing sheets conveyed from said first and second switchback convey paths into said first and second storing sections therein, respectively arranged in said first and second storing sections so as to smoothly convey the sheets;
• wherein each of said guide members comprises:
• a loop-like main guide member for guiding only substantially central portions of sheets conveyed from said first and second storing switchback convey paths into said first and second storing sections;
• and loop-like auxiliary guide members arranged to be substantially symmetrical about said main guide member so as to guide only two side end portions of the sheet, and said auxiliary guide member has an inner diameter larger than an inner diameter of said main guide member.

A sheet discharge processing device for sequentially discharging sheets, sent through image forming means for forming images on the sheets on the basis of image data, onto a discharge tray with image-bearing surfaces of the sheets facing up or down, comprising:

• first and second switchback convey paths being vertically arranged between an inlet path into which a sheet conveyed through said image forming means is conveyed and a discharge path for discharging a sheet onto the discharge tray, and said first and second switchback convey paths being adapted to reverse the front and back of sheets;
• a switching gate including a first reverse guide path for causing said first switchback convey path to communicate with the discharge path when said second switchback convey path communicates with said inlet path, a second reverse guide path for causing said second switchback convey path to communicate with the discharge path when said first switchback convey path communicates with said inlet path, and a straight guide path for causing said inlet path to communicate with the discharge path, and said switching gate being rotatable placed between said inlet path and the discharge path;
• first and second storing sections arranged at an upper end portion of said first switchback convey path and a lower end portion of said second switchback convey path to store sheets conveyed through said first and second switchback convey paths;
• and
• loop-like guide members, storing sheets conveyed from said first and second switchback convey paths into said first and second storing sections therein, respectively arranged in said first and second storing sections so as to smoothly convey the sheets;
• wherein said guide members are divided into a plurality of members and are formed such that the number of the plural guide members decreases in a direction in which sheets are conveyed from said first and second switchback convey paths into said first and second storing sections.

A sheet discharge processing device for sequentially discharging sheets, sent through image forming means for forming images on the sheets on the basis of image data, onto a discharge tray with image-bearing surfaces of the sheets facing up or down, comprising:

• first and second switchback convey paths being vertically arranged between an inlet path into which a sheet conveyed through said image forming means is conveyed and a discharge path for discharging a sheet onto the discharge tray, and said first and second switchback convey paths being adapted to reverse the front and back of sheets;
• a switching gate including a first reverse guide path for causing said first switchback convey path to communicate with the discharge path when said second switchback convey path communicates with said inlet path, a second reverse guide path for causing said second switchback convey path to communicate with the discharge path when said first switchback convey path communicates with said inlet path, and a straight guide path for causing said inlet path to communicate with the discharge path, and said switching gate being rotatably placed between said inlet path and the discharge path;
• first and second convey rollers being respectively arranged on said first and second switchback convey paths, and said first and second convey rollers being able to be rotated in forward and reverse directions;
• first and second detection sensors being arranged between said first and second convey rollers and said switching gate to detect sheets conveyed into said first and second switchback convey paths;
• and
• control means for controlling rotation of said first and second convey rollers, and controlling a rotation position of said switching gate to reverse and discharge a sheet through said first or second switchback convey path when a trailing end of the sheet conveyed into one of said first and second switchback convey paths is detected by said first or second detection sensor, and discharge processing of a sheet in the other switchback convey path, which is different from said switchback convey path in which the trailing end of the sheet has been detected, is completed.

A sheet discharge processing device for sequentially discharging sheets, sent through image forming means for forming images on the sheets on the basis of image data, onto a discharge tray with image-bearing surfaces of the sheets facing up or down, comprising:

• first and second switchback convey paths being vertically arranged between an inlet path into which a sheet conveyed through said image forming means is conveyed and a discharge path for discharging a sheet onto the discharge tray, and said first and second switchback convey paths being adapted to reverse the front and back of sheets;
• a switching gate including a first reverse guide path for causing said first switchback convey path to communicate with the discharge path when said second switchback convey path communicates with said inlet path, a second reverse guide path for causing said second switchback convey path to communicate with the discharge path when said first switchback convey path communicates with said inlet path, and a straight guide path for causing said inlet path to communicate with the discharge path, and said switching gate being rotatably placed between said inlet path and the discharge path;
• first and second convey rollers being respectively arranged on said first and second switchback convey paths, and said first and second convey rollers being able to be rotated in forward and reverse directions;
• first and second detection sensors being arranged between said first and second convey rollers and said switching gate to detect sheets conveyed into said first and second switchback convey paths;
• timer means in which a time taken for a trailing end of a sheet discharged from said first or second switchback convey path to pass completely through one of the reverse guide paths of said switching gate is set in advance, and said timer means starting to count the set time in response to starting a discharge operation for a sheet;
• and
• control means for controlling rotation of said first and second convey rollers, and controlling a rotation position of said switching gate to reverse and discharge a sheet through said first or second switchback convey path after a trailing end of the sheet conveyed into one of said first and second switchback convey paths is detected by said first or second detection sensor, and it is determined that said timer means has completely counted the set time.