Single automatic document feeder sensor for media leading edge and top cover being opened detection

• US 7,139,108 B2
• Filed: 07/28/2003
• Issued: 11/21/2006
• Est. Priority Date: 07/20/2000
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Andersen, Eric L., Mui, Paul K.
• Primary Examiner(s): Lee, Thomas D.
• Assistant Examiner(s): Gibbs, Heather D
• Application Number:
  US10/628,785
• Publication Number:
  US 20040070798A1
• Time in Patent Office: 1,212 Days
• Field of Search: 358/498, 358/488, 358/474, 358/497, 358/400, 250/208.1, 250/222.1, 271/117, 271/157, 271/10.03, 399/370, 399/374, 399/367
• US Class Current: 358/474
• CPC Class Codes: G03G 15/607 for detecting size, presence or position of original
• CPC Class Codes: H04N 1/00551 Top covers or the like
• CPC Class Codes: H04N 1/00588 to the scanning position H04N1/00572, H04N1/00594 take precedence
• CPC Class Codes: H04N 1/00681 Detecting the presence, position or size of a sheet or correcting its position before scanning H04N1/047 takes precedence; mode signalling H04N1/333; skew detection or correction in image signals H04N1/3878
• CPC Class Codes: H04N 1/00702 Position
• CPC Class Codes: H04N 1/00732 Mechanical detectors
• CPC Class Codes: H04N 1/00745 Detecting the leading or trailing ends of a moving sheet

Abstract

A single plate flatbed scanner utilizing a single sensor to detect both opening of a lid covering the plate and the leading edge of an automatically fed document. The flatbed scanner includes a contact glass plate defining a flatbed scanning area where a document to be scanned may be manually positioned. An automatic document feeder (ADF) scan window where ADF-fed documents are scanned is defined within the flatbed scanning area. An image sensor is maintained at a fixed position in the ADF scan window while scanning ADF-fed documents. To scan a manually fed document, the image sensor moves under the flatbed scanning area so as to scan an image of the document. Since the ADF scan window and the flatbed scanning area both are defined in the same area of the contact glass plate, a document inadvertently left on the contact glass blocks the ADF scan window and prevents the scanning of an ADF fed document. A single sensor is utilized to detect the opening of the ADF which uncovers the contact glass to allow manual placement of a document. Detecting the opening of the glass plate cover is used to determine whether or not a document has been left on the glass plate after scanning. The same sensor is also utilized to detect the leading edge of an ADF fed document to initiate the scanning process at the precise time the document reaches the ADF scan window.

Claims

1. An image scanner comprising:

a single contact glass disposed on a main body, the contact glass having a first range through which a first original document is passed to be scanned, and a second range over which a second original document is positioned to be scanned, the second range including the first range;

an image sensor scanning the first original document at a fixed position in the first range and scanning the second original document while the image sensor moves through the second range;

an automatic document feeder arranged on the main body covering the contact glass and being openable to expose the contact glass, the automatic document feeder conveying the first original document through a feed path to the fixed position and ejecting the first original document through an ejecting path from the fixed position; and

a single detector adapted to detect both when the automatic document feeder is opened and to detect a leading edge of the first original document whenever a document page is conveyed along the feed path to the first fixed position.

2. The image scanner as in claim 1 wherein the detector is operatively mounted on the automatic document feeder.

3. The image scanner as in claim 2 wherein the detector comprises an optical switch.

4. The image scanner as in claim 3 wherein the optical switch provides a light beam which is operatively interrupted by a pivotally mounted swing member.

5. The image scanner as in claim 1 further comprising an automatic document feeder controller, the detector electrically coupled to the controller, the controller responsive to signals generated by the detector for preventing the conveyance of a document page of the first original document to the fixed position whenever a document page of the second original document is positioned on the contact glass in the second range.