PASSAGE SELECTOR OF REACTOR IN-CORE NUCLEAR-MEASURING APPARATUS

• US 20090316851A1
• Filed: 11/14/2008
• Published: 12/24/2009
• Est. Priority Date: 06/18/2008
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Yodogawa, Masami, Oosaka, Kenji
• Granted Patent: US 8,744,033 B2
• Time in Patent Office: Days
• US Class Current: 376/245
• CPC Class Codes: G21C 13/036 the tube passing through the vessel wall, i.e. continuing on both sides of the wall
• CPC Class Codes: G21C 17/00 Monitoring; Testing measuring in general G01; Maintaining
• CPC Class Codes: G21C 17/108 Measuring reactor flux
• CPC Class Codes: G21C 17/116 Passages or insulators, e.g. for electric cables
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

An object of the invention is to embody a small and inexpensive passage selector, which can be applied by commonly using an index device even if the number of detector passages is changed, and which is easy to make inspection and maintenance. The passage selector of a reactor in-core nuclear-measuring apparatus of the invention includes: a drive motor; an index device that is driven by the drive motor and that makes a rotary output of a predetermined index number; a central rotating shaft that is driven to rotate by the index device and that causes a passage selecting guide tube to be located in opposition to any detector passage; and a speed-increasing and decreasing device that is interposed between an output shaft of the index device and the central rotating shaft, and that adjusts the index number of the central rotating shaft.

Claims

1. A passage selector of a reactor in-core nuclear-measuring apparatus comprising:

a drive motor;

an index device that is driven by said drive motor and that makes a rotary output of a predetermined index number;

a central rotating shaft that is driven to rotate by said index device and that causes a passage selecting guide tube to be located in opposition to any detector passage; and

a speed-increasing and decreasing device that is interposed between an output shaft of said index device and the central rotating shaft, and that adjusts the index number of said central rotating shaft.

2. The passage selector of a reactor in-core nuclear-measuring apparatus according to claim 1, wherein said speed-increasing and decreasing device comprises a first gear connected to an output shaft of the index device and a second gear that is meshed with said first gear and connected to said central rotating shaft.

3. The passage selector of a reactor in-core nuclear-measuring apparatus according to claim 1, wherein when letting a stop number (index number) of the index device Y, a teeth number of the first gear 23 Z1, and a teeth number of the second gear 24 Z2, the stop number (index number) of the central rotating shaft is set to be Y×

Z2/Z1.

4. The passage selector of a reactor in-core nuclear-measuring apparatus according to claim 2, wherein when letting a stop number (index number) of the index device Y, a teeth number of the first gear 23 Z1, and a teeth number of the second gear 24 Z2, the stop number (index number) of the central rotating shaft is set to be Y×

Z2/Z1.

5. The passage selector of a reactor in-core nuclear-measuring apparatus according to claim 1, wherein said speed-increasing and decreasing device is formed of a toothed belt and a pulley in combination.

6. The passage selector of a reactor in-core nuclear-measuring apparatus according to claim 1, wherein said speed-increasing and decreasing device is formed of a chain and a sprocket in combination.