Apparatus for dispensing detergent in a warewash machine

An apparatus for dispensing detergent in a warewash machine including a washtank for holding a predetermined supply of wash water supplied during a fill cycle, a rinse water spray head for spraying water over a rack of wares and into the washtank during a rinse cycle, and an overflow drain for draining excess water introduced into the washtank during a rinse cycle, the apparatus comprising:

• means for determining whether the water is being supplied to the washtank during a fill cycle or a rinse cycle;
• means for dispensing detergent to the washtank of the warewash machine;
• first control means, coupled with the determining means and the dispensing means, for causing the dispensing means to dispense a first predetermined amount of detergent during or after a fill cycle;
• and
• second control means, coupled with the determining means and the dispensing means, for causing the dispensing means to dispense after the rinse cycle is complete a second predetermined amount of detergent to compensate for the detergent drained from the washtank during a rinse cycle.

An apparatus for dispensing detergent in a warewash machine including a washtank for holding a supply of wash water and a rinse water spray head through which water is supplied in a rinse cycle and in a fill cycle, the apparatus comprising:

• a relay switch operatively connected to the rinse water spray head, said relay switch generating a signal in response to water being supplied through the rinse water spray head;
• an operation determination timer for receiving the signal generated by the relay switch, the signal activating the operation determination timer for a predetermined time, said operation determination timer generating a delayed signal after the predetermined time has elapsed;
• a control circuit for receiving the delayed signal generated by the operation determination timer and the signal generated by the relay switch;
• a variable speed pump for dispensing detergent to the washtank of the warewash machine;
• a pre-charge timer operatively connected to the variable speed pump for operating said pump for a first predetermined period of time, the control circuit generating a first control signal to activate the pre-charge timer at times when the relay switch is generating a signal after the predetermined time elapsed;
• and
• a make-up timer operatively connected to the variable speed pump for operating said pump for a second predetermined period of time, the control circuit generating a second control signal to activate the make-up timer at times when the relay switch is not generating a signal after the predetermined time, said second control signal being generated after the rinse cycle is complete.