US 4,068,162 A · Rinse tank control system

Abstract

A control system for a water rinse tank or the like which continuously monitors the rinse water quality by means of electrical conductivity and adds clean water when the water-contamination conductivity of the rinse water builds up through use to a predetermined value. A conductivity cell which is transparent and may be disassembled, and adjustable for operation over a wide range of conductivity settings. A power circuit with triac for switching power to a valve solenoid. A silicon controlled rectifier (SCR) and its associated circuitry located at the conductivity cell for controlling the triac, with the SCR operation directly controlled by the conductivity cell. A zener diode-transistor voltage regulating circuit for consistently maintaining substantially the same spiked waveform across the conductivity cell both for water off and water on conditions.

Claims20

Dependent claims

A conductivity cell for use in a control system for a rinse tank and the like having a tank for water, a water inlet line, flow control means for controlling flow in said inlet line and circuit means for operating said flow control means in response to the conductivity cell, the cell comprising in combination:

first and second electrodes;
means for mounting said electrodes in spaced relation for immersion in the tank;
and
means for moving one of said electrodes relative to the other,
with said first electrode being a sleeve and said second electrode being a plug mounted coaxial with said first electrode for movement along the axis.

2 more elements

A conductivity cell foruse in a control system for a rinse tank and the like having a tank for water, a water inlet line, flow control means for controlling flow in said inlet line and circuit means for operating said flow control means in response to the conductivity cell, the cell comprising in combination:

first and second electrodes;
means for mounting said electrodes in spaced relation for immersion in the tank;
and
means for moving one of said electrodes relative to the other;
said circuit means including in combination:
a pair of terminals;
means for connecting an ac electrical power source across said terminals;
a first rectifier connected across said terminals with one polarity;
a second controlled rectifier connected across said terminals with the opposite polarity;
a voltage divider connected across said terminals, with a point of said divider connected to the control electrode of said second rectifier for firing said second rectifier;
first means connecting said cell to said divider circuit in shunt relation with said second rectifier control electrode;
and
second means connected to said divider circuit in shunt relation with said cell for reducing the voltage across said cell when the voltage at said terminals exceeds a predetermined value.

10 more elements

A control system for use in a rinse tank and the like having a water inlet line and a valve for controlling flow in said inlet line, including in combination:

a conductivity cell for positioning in said tank;
a pair of terminals;
means for connecting an ac electrical power source across said terminals;
a first rectifier connected across said terminals with one polarity;
a second controlled rectifier connected across said terminals with the opposite polarity;
a voltage divider connected across said terminals, with a point of said divider connected to the control electrode of said second rectifier for firing said second rectifier;
first means connecting said cell to said divider circuit in shunt relation with said second rectifier control electrode;
and
second means connected to said divider circuit in shunt relation with said cell for reducing the voltage across said cell when the voltage at said terminals exceeds a predetermined value.

6 more elements

Dependencies are inferred from the claim text.

Rinse tank control system

Life of this patent

Rinse tank control system

Life of this patent

Abstract

Claims20