Document reading unit with easily removable document contact glass, and scanner and image forming apparatus using the same
View Patent ↗A document reading unit has an image sensor mounted in a box-like support base so that a document can be read by the image sensor through an opening in the support base. A contact glass disposed in the opening covers the image sensor and supports the document while it is being read by the image sensor. Support members coupled to the contact glass are detachably fixed to the support base by fixing screws. The image sensor has two rows of spaced-apart line sensors with the line sensors in one row staggered relative to those in the other row, and the support members are arranged between adjacent pairs of line sensors in each row of line sensors. The contact glass and support members are removable as a unit from the support base.
1. A document reading unit comprising:
an image sensor for reading a document, the image sensor including a plurality of sensor arrays each formed of multiple line sensors arranged in a widthwise direction perpendicular to a direction in which the document is conveyed;
a support base having a box-like shape for internally accommodating and supporting the image sensor, and an opening through which the image sensor faces the document;
a document support plate that is located at the opening for covering the image sensor and supporting the document while it is being conveyed to the image sensor;
plate support members linked with the document support plate and arranged on the support base at the longitudinal ends of each of the line sensors for supporting the document support plate;
fixing portion for detachably fixing the plate support members to the support base;
spacers located between the line sensors and the document support plate; and
pressing members for pressing the line sensors toward the document support plate.
2. A document reading unit according to claim 1 ; wherein fixing members for engaging a document sliding face of the document support plate and securing the document support plate are located at both side ends of the document support plate, outside the document conveying area and parallel to the direction in which the document is conveyed.
3. A document reading unit according to claim 1 ; wherein the plate support members are bonded to reverse face of a document sliding face of the document support plate.
4. A document reading unit according to claim 1 ; wherein the plate support members are integrally formed with the document support plate.
5. A document reading unit according to claim 1 ; wherein the fixing portions comprise fixing screws that detachably secure the plate support members to the support base.
6. A scanner comprising:
a document reading unit according to claim 1 ; and
a conveying unit for conveying a document to an image sensor in the document reading unit.
7. An image forming apparatus comprising:
a document reading unit according to claim 1 ,
wherein an image is formed based on data for a document read by the document reading unit.
8. A document reading unit comprising:
an image sensor having two rows of line sensors for reading a document, the line sensors in each row being longitudinally spaced apart from one another and staggered with respect to the line sensors in the other row;
an enclosure that accommodates and supports therein the image sensor, the enclosure having an opening through which the image sensor faces a document to be read;
a document support plate that is located at the opening and overlies the image sensor and that supports the document while it is being read;
plate support members coupled to the document support plate and disposed, respectively, between adjacent pairs of line sensors in each row of line sensors; and
fasteners that detachably fasten the plate support members to the enclosure to enable removal of the document support plate and the plate support members, as a unit, from the enclosure.
9. A document reading unit according to claim 8 ; wherein the plate support members are bonded to an underside of the document support plate.
10. A document reading unit according to claim 8 ; wherein the plate support members are adhered to an underside of the document support plate by double-sided adhesive tape.
11. A document reading unit according to claim 8 ; wherein the fasteners comprise screws.
12. A document reading unit according to claim 8 ; wherein the document support plate comprises a glass plate.
13. A document reading unit according to claim 8 ; further comprising spacers disposed between the document support plate and respective ones of the line sensors.
14. A document reading unit according to claim 13 ; further comprising resilient pressing members for pressing the line sensors toward the document support plate.
15. A document reading unit according to claim 8 ; wherein one plate support member is disposed between each adjacent pair of line sensors in each row of line sensors.
16. A document reading unit according to claim 15 ; further comprising spacers disposed between the document support plate and respective ones of the line sensors.
17. A document reading unit according to claim 16 ; further comprising resilient pressing members for pressing the line sensors toward the document support plate.
18. A document reading unit according to claim 17 ; wherein the plate support members are bonded to an underside of the document support plate.
19. A scanner comprising:
a document reading unit according to claim 8 : and
a conveying unit for conveying a document along the document support plate to be read by the image sensor of the document reading unit.