Patent ID: 11946776
Assignee: 7-ELEVEN, INC.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. A circuit board for counting items stored in a rack, comprising:
a longitudinal rack that stores a plurality of items of a first thickness along a length of the rack between a front end and rear end of the rack;
a shoe movably attached to the rack such that the shoe travels between the front end and the rear end of the rack, wherein the items are placed adjacent to a front end of the shoe, wherein the shoe is pushed back towards the rear end of the rack with each item loaded on the rack;
a magnet coupled to the shoe; and
a longitudinal circuit board arranged along the length of the rack and comprising:
an array of sensors arranged along a length of the circuit board, wherein:
the circuit board is arranged along a length of the rack that stores a plurality of items of a first thickness along the length of the rack between a front end and a rear end of the rack;
a spacing between each pair of the sensors corresponds to a pre-selected spacing;
the magnet is arranged in relation to the circuit board such that a longitudinal axis of the magnet is parallel to the longitudinal circuit board;
at least a subset of the sensors generates a signal corresponding to a strength of a magnetic field associated with the magnet; and
the signal generated by the subset of the sensors is based at least in part upon a position of the magnet in relation to the sensor;

a memory that stores values corresponding to the signal generated by the subset of the sensors; and
a processor communicatively coupled to the sensors and the memory, wherein the processor is configured to:
monitor the values generated by the subset of the sensors;
detect that a first sensor has generated a first highest absolute value and a second sensor has generated a second highest absolute value, wherein the first highest absolute value and the second highest absolute value are the two highest values out of the values generated by the sensors in the array;
determine a position of the magnet along the length of the rack based at least in part upon a first distance of the first sensor from the front end of the rack and a second distance of the second sensor from the front end of the rack, wherein the position of the magnet comprises a distance of the magnet from the front end of the rack; and
determine a number of items of the first thickness stored in the rack based on the position of the magnet along the length of the rack.