Sensor device having first induction coil set and second induction coil set for determining position change of metal item
A sensor device is configured to be disposed on a surface of a side of an object. The sensor device includes a casing, and the casing has a first side that is distant from the object and a second side that is relatively closer to the object. A first induction coil set is disposed on the first side, and a second induction coil set is disposed on the second side. The sensor device further includes a control circuit board. The control circuit board includes a connection line that is electrically connected with the first induction coil set and the second induction coil set, and a microcontroller. When the sensor device is in operation, the microcontroller determines a position change of a metal item on another side of the object according to a physical quantity difference between the first induction coil set and the second induction coil set.
1 . A sensor device, which is configured to be disposed on a surface of a side of an object, comprising:
a casing having a first side that is distant from the object and a second side that is closer than the first side to the object;
a first induction coil set disposed on the first side;
a second induction coil set disposed on the second side; and
a control circuit board having a connection line that is electrically connected with the first induction coil set and the second induction coil set, and a microcontroller,
wherein the microcontroller determines a position change of a metal item disposed on another side of the object according to a physical quantity difference between the first induction coil set and the second induction coil set,
wherein the second induction coil set is disposed between the object and an exterior wall of the casing facing the object,
wherein the first induction coil set comprises two coils mounted on two sides of a first substrate, and the second induction coil set comprises another two coils mounted on two sides of a second substrate, and
wherein a cavity is defined between one of the two coils of the first induction coil set facing the second induction coil set and one of the two coils of the second induction coil set facing the first induction coil set.
2 . The sensor device according to claim 1 , wherein the object is a holster for accommodating a gun, the gun has the metal item, the sensor device is disposed on the holster, and the sensor device corresponds in position to the metal item when the gun is put inside the holster.
3 . The sensor device according to claim 1 , wherein the first induction coil set is a reference coil set that forms a reference level, and the second induction coil set is an induction coil set that forms an inductive inductance.
4 . The sensor device according to claim 1 , wherein a containing slot is formed on the second side of the casing, and the second induction coil set is disposed in the containing slot.
5 . The sensor device according to claim 1 , wherein an opening is formed on a wall structure of the casing that has the second induction coil set disposed thereon, such that the second induction coil set and the first induction coil set are unobstructed by the wall structure.
6 . The sensor device according to claim 1 , wherein the casing has a positioning hole that is configured as an airtight evacuation hole for a cavity formed by the casing.
7 . The sensor device according to claim 6 , wherein the airtight evacuation hole is sealed by a waterproof breathable membrane.
8 . The sensor device according to claim 6 , wherein the second induction coil set has an opening that corresponds to the positioning hole.
9 . The sensor device according to claim 1 , wherein the control circuit board further comprises a communication unit electrically connected with the microcontroller, and the communication unit is used to transmit an activation signal that is generated by the microcontroller according to the physical quantity difference.
10 . The sensor device according to claim 1 , wherein the control circuit board further comprises a power unit that is electrically connected with the microcontroller and is controlled by the microcontroller, and the power unit provides current signals to the first induction coil set and the second induction coil set for generating an induced magnetic field.
11 . The sensor device according to claim 10 , wherein the first induction coil set is a reference coil set that forms a reference level, and the second induction coil set is an induction coil set that forms an inductive inductance.
12 . The sensor device according to claim 1 , wherein the sensor device implements a proximity sensor or a differential inductive switch, the first induction coil set and the second induction coil set respectively form two different effective sensing ranges, so as to form a reference inductance and an inductive inductance, and when a position of the metal item changes, an inductance difference between the reference inductance and the inductive inductance also changes.
13 . The sensor device according to claim 12 , wherein the first induction coil set is a reference coil set that forms a reference level, and the second induction coil set is an induction coil set that forms the inductive inductance.
14 . The sensor device according to claim 1 , wherein the casing defines a containing slot disposed between a first sidewall of the casing, a second sidewall of the casing, and the exterior wall extending between the first sidewall and the second sidewall.
15 . The sensor device according to claim 1 , wherein a total inductive area of the first induction coil set is smaller than a total inductive area of the second induction coil set.
16 . The sensor device according to claim 1 , wherein the second induction coil set is disposed between the object and the exterior wall of the casing facing the object such that the second induction coil set is disposed on an exterior of the casing.
17 . The sensor device according to claim 1 , wherein the second induction coil set is disposed between the object and the exterior wall of the casing facing the object such that the second induction coil set is co-planar with a surface of the exterior wall closest to the object.