Automatic calibrating apparatus for laboratory ion concentration meter

• US 5,511,408 A
• Filed: 07/28/1993
• Issued: 04/30/1996
• Est. Priority Date: 07/30/1992
• Status: Expired due to Fees

• Current Assignee: Horiba Limited
• Original Assignee: Horiba Limited
• Inventors: Ohkawa, Hiromi, Yoshioka, Nobuki
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): LARKIN, DANIEL SEAN
• Application Number:
  US08/098,508
• Time in Patent Office: 1,007 Days
• Field of Search: 73/1 R, 324/438, 324/601, 204/153.21, 204/433, 422/67, 422/82.03, 436/43, 436/163, 436/73, 436/324
• US Class Current: 73/1.03
• CPC Class Codes: G01N 27/4165 for pH meters
• CPC Class Codes: Y10T 436/11 Automated chemical analysis

Abstract

An automatic calibrating apparatus for a measurement instrument having a sensor member includes a chamber adapted to hold the sensor member during a storage mode. A controller can respond to the presence of the sensor member and automatically wash the sensor member, and subsequently immerse it in a calibration solution. The output reading of the sensor member, along with the temperature, can then be utilized to calibrate the instrument. The sensor member can be subsequently cleansed with a washing fluid so that it is ready for immediate use.

Claims

1. An automatic calibrating apparatus for supporting a separate portable measuring instrument with a portable sensor member comprising:

a hollow storage receptacle, independent of the measuring instrument, having a cavity with an entrance opening annular seal dimensioned to removably suspend a sensor member within the receptacle;

determining means for determining the insertion of the sensor member into the storage receptacle including a switch member;

an inlet conduit attached to the storage receptacle;

an outlet conduit attached to the storage receptacle wherein the inlet conduit is attached to the storage receptacle adjacent the bottom of the cavity and the outlet conduit is attached to the storage receptacle adjacent an upper side surface of the cavity;

means for storing separate fluids including a calibration solution and a washing solution;

means for selectively applying the fluids to the inlet conduit for delivery to the hollow storage receptacle;

means for activating a calibration procedure when enabled by the determination of the determining means that a sensor member is mounted in the storage receptacle, including means for coordinating which includes a controller operatively connectable to the separate portable measuring instrument, for coordinating first, the introduction of the washing solution into the receptacle and the subsequent removal of the washing solution, and second, the introduction of the calibration solution and removal of the calibration solution;

means for storing a measurement signal from the sensor member during the presence of the calibration solution;

means for automatically comparing the measurement signal with a stored reference value and providing a corresponding adjustment of the sensor member output signal; and

means for removably connecting the controller with the measuring instrument to permit the corresponding adjustment of the sensor member output signal.

2. The invention of claim 1 further including means for measuring the temperature of the calibration solution.

3. The invention of claim 1 further including a second calibration solution.

4. The invention of claim 1 wherein the means for coordinating includes a series of valves operatively connected to the controller.

5. The invention of claim 1 further including a pump and a waste tank for receiving the removed washing solution and calibration solution when the pump is activated by the controller.

6. An automatic calibrating apparatus for calibrating a separate portable measuring instrument with a portable sensor member comprising:

a hollow storage receptacle, independent of the measuring instrument, having a cavity dimensioned to suspend a sensor member within the receptacle, including an upper aperture extending across the hollow storage receptacle and an annular seal configured to sealingly and removably receive a sensor member so that an electrode portion is positioned in close proximity to a bottom of the cavity receptacle;

an inlet conduit attached to the storage receptacle;

an outlet conduit attached to the storage receptacle of the cavity wherein the inlet conduit is attached to the storage receptacle adjacent the bottom of the cavity and the outlet conduit is attached to the storage receptacle adjacent an upper side surface of the cavity;

means for storing separate fluids including a calibration solution and a washing solution;

means for selectively applying the fluids to the inlet conduit for delivery to the hollow storage receptacle;

means for activating a calibration procedure, including means for coordinating which includes a controller operatively connectable to the separate portable measuring instrument, for coordinating first, the introduction of the washing solution into the receptacle and the subsequent removal of the washing solution, and second, the introduction of the calibration solution and removal of the calibration solution;

means for storing a measurement signal from the sensor member during the presence of the calibration solution;

means for automatically comparing the measurement signal with a stored reference value and providing a corresponding adjustment of the sensor member output signal; and

means for removably connecting the controller with the measuring instrument to permit the corresponding adjustment of the sensor member output signal.

7. The invention of claim 6 further including means for measuring the temperature of the calibration fluid.

8. The invention of claim 6 further including means for storing a second calibration fluid.

9. The invention of claim 6 wherein the means for coordinating includes a series of Valves operatively connected to the controller.

10. The invention of claim 6 further including a pump and a waste tank for receiving the removed washing solution and calibration solution when the pump is activated by the controller.