DEVICE FOR MEASURING PERMITTIVITY OF MATERIALS

• US 3,671,857 A
• Filed: 04/29/1970
• Issued: 06/20/1972
• Est. Priority Date: 04/29/1970
• Status: Expired due to Term

• Current Assignee: 61, kv. 19, kv., 19, Soviet Union, Soviet Union Riga, Ulitsa Graudu Karlis Alfredovich Bergmanis, Ulitsa Tvaika Erik Ernestovich Klotinsh
• Original Assignee: 61, kv. 19, kv., 19, Soviet Union, Soviet Union Riga, Ulitsa Graudu Karlis Alfredovich Bergmanis, Ulitsa Tvaika Erik Ernestovich Klotinsh
• Inventors: Karlis Alfredovich Bergmanis, ULITSA Graudu, Riga, Soviet Union, Erik Ernestovich Klotinsh, ULITSA Tvaika, kv., 19, 61, kv. 19, Soviet, Union
• Primary Examiner(s): Alfred E. Smith
• Application Number:
  US05/032,823
• Time in Patent Office: 783 Days
• Field of Search: 324/61TI
• US Class Current: 324/663
• CPC Class Codes: G01N 27/228 Circuits therefor measuring capacitance per se G01R27/26

Abstract

A device for measuring permittivity of materials on the basis of at least two different capacitance values of a measuring capacitor connected to the material being tested and to a measuring oscillator the output of which is coupled to one input of a mixer whose other input is coupled to a reference oscillator and whose output is coupled through a frequency meter to a resetting unit, characterized in that the measuring capacitor has at least two main electrodes permanently connected to the input of the measuring electrodes permanently connected to the input of the measuring oscillator, and one additional electrode alternately connected by a switch to one of the main electrodes in the course of measurement, while said resetting unit is connected to a pulse counter of the frequency meter through a switch actuated synchronously with said switch of the measuring capacitor electrodes so that in one position of this switch the frequency of the measuring oscillator is above, and in the other position of the switch, below the frequency of the reference oscillator.

Claims

1. A device for measuring permittivity of materials on the basis of at least two different capacitance values of a measuring capacitor connected to the material being tested and comprising at least two main electrodes and one additional electrode;

a measuring oscillator the input of which is permanently connected to both of said main electrodes;

a first switch which selectively connects said additional electrode to either one of said main electrodes in the course of measurement;

a reference oscillator;

a mixer the input of which is coupled to the outputs of both of said oscillators;

a frequency meter, the input of which is coupled to the output of said mixer;

a resetting unit; and

a second switch connected to said first switch for simultaneous actuation therewith, said second switch connecting said resetting unit to said frequency meter in a first position thereof and disconnecting said resetting unit in the other position thereof, whereby in one position of said first and second switches the frequency of said measuring oscillator is above, and in the other position of said switches, below the frequency of said reference oscillator.