Resistance measurement system

Claim 2

A resistance measuring system for measuring the varying change in the value of resistance comprising: a. input circuit means for providing a first output signal proportional to the value of said resistance as said resistance varies; b. an amplifier circuit having said output signal coupled to the input thereof; c. whereby said amplifier circuit produces an amplified output signal proportional to the variation in said resistance and d. indicator means connected to said amplifier circuit for producing an indication representative of both the increase and decrease in said resistance.

Claim 3

A resistance measuring system in accordance with claim 1, wherein said first output signal is an indication of the percentage change in said resistance.

Claim 4

A resistance measuring system in accordance with claim 1, wherein said amplifier circuit includes filtering means for decoupling the input DC level from the amplifier input, said amplifier circuit thereby amplifying only changes in said resistance.

Claim 5

A resistance measuring system in accordance with claim 1, wherein said indicator means provides a first output indication when said resistance increasEs beyond a predetermined level and a second output indication when said resistance decreases below said predetermined level.

Claim 6

A resistance measurement system in accordance with claim 1, wherein said input circuit is responsive only to changes in said resistance.

Claim 7

A resistance measuring system in accordance with claim 1, wherein the AC current of said input circuit is proportional to ( Delta R/R) where Delta R is the incremental change in said resistance; and R is the value of said resistance.

Claim 8

A resistance measuring measuring for mesuring the change in the value of a resistance comprising: input circuit means for providing first output signal proportional the value of said resistance; an amplifier circuit having said output signal coupled to the input thereof, said amplifier circuit producing a second output signal proportional to the change in said resistance; indicator means connected to said amplifier circuit for producing a third output representative of a change in said resistance, wherein said input circuit comprises a transistor connected in emitter-follower configuration, said resistance being coupled across the base-collector circuit of said transistor and wherein amplified output signals representative of said value of resistor are coupled from the emitter of said transistor to a filter the output signal of which is representative of changes in said resistance, and wherein said filter output signal is coupled to an operational amplifier, and further wherein said output operational amplifier is coupled to a pair of transistors, one of said transistors being conductive when said resistance change increases beyond a predetermined value and the other of said transistors being conductive when said resistance change decreases beyond a predetermined value.

Claim 9

A resistance measuring measuring for mesuring the change in the value of a resistance comprising: input circuit means for providing first output signal proportional the value of said resistance; an amplifier circuit having said output signal coupled to the input thereof, said amplifier circuit producing a second output signal proportional to the change in said resistance; indicator means connected to said amplifier circuit for producing a third output representative of a change in said resistance, wherein said input circuit comprises a transistor connected in emitter-follower configuration, said resistance being coupled across the base-collector circuit of said transistor and wherein amplified output signals representative of said value of resistor are coupled from the emitter of said transistor to a filter the output signal of which is representative of changes in said resistance, and wherein said filter output signal is coupled to an operational amplifier, and further wherein said output operational amplifier is coupled to a pair of transistors, one of said transistors being conductive when said resistance change increases beyond a predetermined value and the other of said transistors being conductive when said resistance change decreases beyond a predetermined value.

Claim 10

A resistance measuring system in accordance with claim 1 including a pair of electrodes connected to said input circuit adapted to contact the resistance to be measured.