Time adjustment device, timekeeping device with a time adjustment device, and a time adjustment method

• US 8,488,417 B2
• Filed: 11/08/2011
• Issued: 07/16/2013
• Est. Priority Date: 08/02/2007
• Status: Expired due to Fees

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Fujisawa, Teruhiko
• Primary Examiner(s): Miska, Vit W
• Application Number:
  US13/291,506
• Publication Number:
  US 20120051191A1
• Time in Patent Office: 616 Days
• Field of Search: 368/46, 368/47, 342/357.66, 342/357.74
• US Class Current: 368/47
• CPC Class Codes: G04R 20/04 Tuning or receiving; Circuits therefor
• CPC Class Codes: G04R 20/06 Decoding time data; Circuits therefor
• CPC Class Codes: G04R 60/12 inside metal cases

Abstract

A time adjustment device having a time information generating unit that generates and outputs time information containing internal time data; a reception unit that receives satellite signals transmitted from a positioning information satellite in subframe information units; an external input unit that generates, through manual operation thereof, command information that instructs the reception unit to enter a reception mode; a reception timing start setup unit that, when in the reception mode, sets the start time of reception so that the subframe information units are acquired at the time determined by the internal time data; and a corrected time information storage unit that stores the satellite-time-related information as corrected time information. A determination unit determines whether the satellite-time-related information received in a particular segment of subframe information unit(s) is correct or erroneous, and if correct, is used as time adjustment information to correct the generated time information.

Claims

1. A time adjustment device comprising:

a time information generating unit that generates time information containing internal time data and that outputs the generated time information;

a reception unit that receives satellite signals transmitted sequentially from a positioning information satellite in subframes that comprise subframes 1 to 5 and that contain satellite-time-related information;

an external input unit that generates, through manual operation of an external operating unit, command information that instructs the reception unit to enter a reception mode;

a reception timing start setup unit that, when in the reception mode, sets the start time of reception by the reception unit so that at least one subframe is acquired at the time determined by the internal time data; and

a corrected time information storage unit that stores the satellite-time-related information;

wherein the reception unit comprises a determination unit that determines whether the satellite-time-related information received in a particular segment of one or more subframes is correct or erroneous, and if correct, is used as time adjustment information,

wherein the generated time information is corrected based on the time adjustment information, if a correction amount is less than or equal to a prescribed threshold amount, and

wherein, if the correction amount exceeds threshold amount, then the satellite-time-related information received in a subsequent subframe is stored, and if consistent, the generated time information is corrected based on the satellite-time-related information.

2. The time adjustment device described in claim 1, wherein the positioning information satellite is a GPS satellite.

3. The time adjustment device described in claim 1, wherein a week number is contained in subframe 1, and the reception unit receives the week number.

4. A time adjustment device comprising:

a time information generating unit that generates time information containing internal time data and that outputs the generated time information;

a reception unit that receives satellite signals transmitted sequentially from a positioning information satellite in subframes that comprise subframes 1 to 5 and that contain satellite-time-related information;

an external input unit that generates, through manual operation of an external operating unit, command information that instructs the reception unit to enter a reception mode;

a reception timing start setup unit that, when in the reception mode, sets the start time of reception by the reception unit so that at least one subframe is acquired at the time determined by the internal time data; and

a corrected time information storage unit that stores the satellite-time-related information;

wherein the reception unit comprises a determination unit that determines whether the satellite-time-related information received in a particular segment of one or more subframes is correct or erroneous, and if correct, is used as time adjustment information,

wherein the generated time information is corrected based on the time adjustment information, if a correction amount is less than or equal to a prescribed threshold amount,

wherein, if the correction amount exceeds the prescribed threshold amount, then the satellite-time-related information received in each of a plurality of subsequent subframes is stored by unit as satellite time data, one out of at least two of the satellite time data in which the difference approximately matches the difference between the corresponding subframes is selected, and the generated time information is corrected based on the selected satellite time data.

5. A time adjustment device comprising:

a time information generating unit that generates time information containing internal time data and that outputs the generated time information;

a reception unit that receives satellite signals transmitted sequentially from a positioning information satellite in subframes that comprise subframes 1 to 5 and that contain satellite-time-related information;

a corrected time information storage unit that stores the satellite-time-related information;

wherein, if a current corrected amount of time, which is the amount of time the generated time information that is to be corrected based on the satellite-time-related information, exceeds a prescribed threshold amount, then the satellite-time-related information received in a subsequent subframe is stored and if consistent, the generated time information is corrected based on the satellite-time-related information.