Control circuit and method for automatically dispensing beverages

• US 5,228,486 A
• Filed: 05/29/1992
• Issued: 07/20/1993
• Est. Priority Date: 05/29/1992
• Status: Expired due to Term

• Current Assignee: IMI Cornelius Incorporated (Berkshire Hathaway Incorporated)
• Original Assignee: Wilshire Partners
• Inventors: Henninger, William K.
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): Douglas, Steven O.
• Application Number:
  US07/890,674
• Time in Patent Office: 417 Days
• Field of Search: 141/198, 141/206, 141/209, 141/217, 141/227, 141/95, 141/359, 141/360
• US Class Current: 141/95
• CPC Class Codes: B67D 1/1238 comprising means for detecting the liquid level in vessels to be filled, e.g. using ultrasonic waves, optical reflexion, probes

Abstract

A control circuit for a beverage dispenser provides accurate uniform automatic cup filling. The circuit includes an initial latch feature which prevents premature shut-off of the dispenser valve and a mechanism for overcoming false cup-fill conditions to assure uniform filling.

Claims

1. A circuit for controlling the flow of beverage into a container having a lip through a dispenser wherein said dispenser comprises an electrically actuated dispensing valve;

said circuit comprising;

cup switch means, sensing placement of said container in said dispenser, said cup switch means having an output adapted to assume a first state in the presence of engagement and a second state in the absence of engagement;

first memory means having a first input receiving said cup switch output, a second input and a first memory means output, said first memory means output adapted to assume and hold a first state upon receiving a first state output from said cup switch means and said first memory means output adapted to assume and hold a second state upon receiving a first state output from said second input;

said dispensing valve adapted to dispense beverage into said container when said first memory means output is in said first state and to not dispense beverage into said container when said first memory means output is in said second state;

sensing means detecting when said container is filled with beverage having an output, said output being in a first state when said container is filled and in a second state when said container is not filled, said sensing means output being applied to said memory means second input;

a first time delay means having an input connected to said first memory means output and an output, said output assuming a first state during a first time delay period after said first memory means output assumes a first state;

first gate means having a first input connected to said cup switch output and a second input connected to said first time delay means output and having a first gate means output, said output adapted to be in a second state when said cup switch means output is in said first state and also for a period corresponding to said first time delay period after said first memory means output changes state from said second state to said first state, said first gate means output adapted to be in a first state when said cup switch means output is in said second state and said first time delay period after said first memory means output changes state from said second state to said first state after said first time delay period has expired, said output being applied to said first memory means second input whereby movement of said container away from said cup switch means will stop dispensing of beverages only after expiration of said first time delay period.

2. The circuit of claim 1, wherein said first gate means output is applied to said first memory means second input through an edge detector.

3. The circuit of claim 1, wherein said first memory means is a flip flop.

4. The circuit of claim 1 further comprising logic means applying a first state input to said first memory means first input after a second time delay period has expired, said second time delay period being initiated by said first memory means output assuming said second state, whereby additional beverage will be dispensed into said container if said container is not filled.

5. The circuit of claim 4, wherein said logic means causes to said first state input to be applied to said first memory means first input twice after a initial cup filled condition.

6. The circuit of claim 1, wherein said first time delay period is about three quarters second.

7. A circuit for controlling the flow of beverage into a container having a lip through a dispenser wherein said dispenser comprises a probe adapted to engage said lip and receive an electrical current through said beverage when said cup is full and an electrically actuated dispensing valve;

said circuit comprising;

a source of positive voltage;

a reference ground;

a cup switch connected to said source of positive voltage having an open state when a cup is not pressed against said probe and a closed state when a cup is pressed against said probe;

a first positive edge detector having an output adapted to emit a positive pulse in response to said cup switch entering said closed state;

a first flip flop having a set input a reset input and an output, said output entering a high state when said set input receives a positive voltage and holding said high state until a high state is applied to said reset input whereupon said output enters a low state, said set input being connected to said first positive edge detector such that said input receives a positive state pulse when said cup switch enters said closed state, said reset input being connected to said probe such that said reset input receives a positive state pulse when said probe receives an electrical current through said beverage;

a first negative edge detector having an output adapted to emit a pulse in response to said first flip flop output entering said high state;

a second flip flop having a set input receiving the output of said first negative edge detector, an output capable of having a high state and a low state and a reset input that will cause output to go to low state;

a first time delay means adapted to receive said second flip flop output and having an output adapted to change state a preselected time after said second flip flop output changes state, said output being connected to said second flip flop reset input;

a second negative edge detector having an output adapted to emit a pulse in response to said second flip flop output entering a high state;

a third flip flop having a set input receiving the output of said second negative edge detector, an output and a reset input connected to a reset means;

a second positive edge detector receiving said third flip flop output and having an output adapted to emit a positive pulse in response to said third flip flop output entering a high state;

a second time delay means adapted to receive said third flip flop output and having an output adapted to change state a preselected time after said second flip flop output changes state;

first gate means having a first input connected to said output of said second negative edge detector and a second input connected to said output of said second time delay means and an output adapted to be substantially identical to said first input when said second input is high;

a first inverter having an input connected to the output of said second time delay means and an output;

a fourth flip flop having a set input connected to said first gate means output, a reset input connected to said first inverter output and an output;

a third positive edge detector receiving said fourth flip flop output and having an output adapted to emit a positive pulse in response to said fourth flip flop output entering a high state;

second gate means having a first input connected to the output of said second positive edge detector and the output of said third positive edge detector output and a second input connected to said cup switch and an output adapted to emit a pulse when said cup switch is in said closed state and either of said second positive edge detector or said third positive edge detector emits a pulse; and

,

means applying said second gate means output to said set input of said first flip flop whereby said container is filled with beverage.

8. The circuit of claim 7, wherein said second gate means comprises an "or" gate having a first input, a second input and an output, and an "and" gate having a first input, a second input and an output, said "or" gate first input being connected to said second positive edge detector, said "or" gate second input being connected to said third positive edge detector, said "or" gate output being connected to said "and" gate first input, said "and" gate second input being connected to said cup switch and said and gate output being said second gate means output.

9. The circuit of claim 7 wherein said first time delay means has a first fixed time delay period for a transition of said second flip flop from said low state to said high state and a second fixed time delay period for a transition of said second flip flop from said low state to said high state, said first fixed time delay period being different from said second fixed time delay period.

10. The circuit of claim 7 additionally comprising a second inverter connected to said cup switch having an output having a low state when said cup switch is closed and a high output state when said cup switch is open;

a third time delay means having an input connected to said first flip flop output and an output, said third time delay means output changing state from a low state to a high state in a third fixed time delay period after said first flip flop output changes from a low state to a high state and a third gate means having a first input connected to said second inverter output and a second input connected to the output of said third time delay means and an output applying high logic to said first flip flop reset in put only when both said first and second inputs of said third gate means are in said high state whereby an open cup switch condition does not stop dispensing for an interval after said cup switch is initially closed by a cup, said interval corresponding to said third time delay period.

11. The circuit of claim 10, wherein said third time delay period is approximately three quarters second.

12. The circuit of claim 7 wherein said reset means is adapted to apply a signal to the reset input of said second flip flop and the reset input of said third flip flop.

13. The circuit of claim 12 wherein said reset means comprises an electrical connection of the output of said first positive edge detector to the reset input of said third flip flop and the reset input of said second flip flop.

14. The circuit of claim 13 wherein the output of said first positive edge detector is connected to the rest input of said second flip flop through an or gate.

15. A circuit for controlling the flow of beverage through a dispensing valve of a dispenser into a container having a lip wherein said dispenser generates a current through the dispensed beverage and comprises a probe means movable from a first position to a second position by applying a force thereagainst and adapted to receive an electrical current from said beverage when said cup is full and generate an electrical output and wherein said dispensing valve is electrically actuated dispensing valve;

said circuit comprising a cup switch having an output, said output having a first state when said probe means is in said second position and a second state when said probe means is in said first position;

memory means having a first input, a second input and an output;

a valve switch adapted to open and close said dispensing valve dependent on the output of said memory means;

logic means accepting said cup switch output and adapted to accept said probe means electrical output and apply a signal to said memory means first input upon said cup switch output attaining said first state and maintaining said signal for a predetermined time period regardless of the output of said cup switch whereby said dispensing valve is opened and an initial amount of beverage is dispensed into said container and apply a signal to said memory means second input upon said probe means receiving a current through said beverage whereby said dispensing valve is closed and apply up to two additional sequential signals to said memory means first input after a selected delay whereby additional beverage will be dispensed if and only if said probe means is not receiving said current through said beverage while said cup switch output remains in said first state.

16. A method of automatically dispensing beverages comprising the following steps providing a dispenser having a cup rest, a probe adapted to detect cup full state, a cup switch having a first output when a cup is pressed against said probe and a second output when said probe is not pressed, an electrically controlled beverage dispensing valve and a control circuit;

placing a cup to be filled with beverage on said cup rest in contact with and pressing against said probe thereby causing said cup switch to have said first output;

automatically latching said beverage dispensing valve in the dispensing state for a first preset time delay period such that said valve will dispense beverage regardless of said cup switch state, said first preset time delay period selected to allow sufficient beverage to be dispensed such that the weight of said cup and dispensed beverage will hold said cup switch in said first state;

automatically continuing said dispensing of said beverage until said cup is removed from said dispenser or said probe detects a cup full state;

upon said probe detecting a first cup full condition, electronically stopping dispensing of said beverage for a second preset time delay period;

upon completion of said second preset time delay period, electronically determining if said probe detects a cup full condition and, if said cup full condition does not exist, automatically restarting dispensing of said beverage until said cup is removed from said dispenser or said probe detects a cup full state;

upon said probe detecting a second cup full condition, automatically stopping dispensing of said beverage for said second preset time delay period;

upon completion of said second preset time delay period, determining if said probe detects a cup full condition and, if said cup full condition does not exist, automatically restarting dispensing of said beverage until said cup is removed from said dispenser or said probe detects a cup full state; and

,

automatically stopping dispensing of said beverage.

17. A method of dispensing beverages comprising the following steps:

providing a dispenser having a cup rest, a probe adapted to detect cup full state, a cup switch having a first output when a cup is pressed against said probe and a second output when said probe is not pressed, an electrically controlled beverage dispensing valve and a control circuit;

placing a cup to be filled with beverage on said cup rest in contact with and pressing against said probe thereby causing said cup switch to have said first output;

automatically electronically latching said beverage dispensing valve in the dispensing state for a first preset time delay period such that said valve will dispense beverage regardless of said cup switch state, said first preset time delay period selected to allow sufficient beverage to be dispensed such that the weight of said cup and dispensed beverage will hold said cup switch in said first state.