Input apparatus and control method for input apparatus
An input apparatus includes: a touch sensor 11 ; a piezoelectric element 13 ; a piezoelectric element drive unit 15 ; a control unit 17 configured to detect a pressure load on the touch sensor 11 based on an output signal of the piezoelectric element 13 and, when the pressure load satisfies a standard to provide a tactile sensation, to control the piezoelectric element drive unit 15 to drive the piezoelectric element 13 such that the tactile sensation is provided to a pressing object; a connection switchover unit 14 configured to selectively connect the piezoelectric element 13 to the control unit 17 or the piezoelectric element drive unit 15 ; and a discharge circuit 16 configured to discharge electric charge in the piezoelectric element 13 . When the pressure load satisfies the standard, the control unit 17 controls the connection switchover unit 14 to connect the piezoelectric element 13 to the piezoelectric element drive unit 15 such that the piezoelectric element 13 is driven, and then controls the discharge circuit 16 to discharge the electric charge in the piezoelectric element 13.
1. An input apparatus comprising:
a touch sensor configured to detect a touch input;
a piezoelectric element mounted on the touch sensor;
a piezoelectric element drive unit configured to drive the piezoelectric element;
a control unit configured to detect a pressure load on a touch face of the touch sensor based on an output signal of the piezoelectric element and to control the piezoelectric element drive unit, when the pressure load detected satisfies a standard to provide a tactile sensation, to drive the piezoelectric element such that the tactile sensation is provided to an object pressing the touch face;
a connection switchover unit configured to selectively connect the piezoelectric element to the control unit or the piezoelectric element drive unit; and
a discharge circuit connected between the piezoelectric element and the connection switchover unit, and configured to discharge electric charge accumulated in the piezoelectric element, wherein
the control unit, when the pressure load detected based on the output signal of the piezoelectric element input via the connection switchover unit satisfies the standard, controls the connection switchover unit to connect the piezoelectric element to the piezoelectric element drive unit such that the piezoelectric element is driven by the piezoelectric element drive unit, and then
the control unit controls the discharge circuit to discharge the electric charge accumulated in the piezoelectric element by controlling the connection switchover unit to connect the piezoelectric element to the control unit.
2. The input apparatus according to claim 1 , wherein
the discharge circuit has a switching element connected between the piezoelectric element and ground, and
the control unit, after vibration of the piezoelectric element by the piezoelectric element drive unit, conducts the switching element for a predetermined period such that the electric charge accumulated in the piezoelectric element is discharged.
3. The input apparatus according to claim 1 , wherein
the discharge circuit has a resistor element connected between the piezoelectric element and ground.
4. A control method of an input apparatus including
a touch sensor configured to detect a touch input,
a piezoelectric element mounted on the touch sensor,
a piezoelectric element drive unit configured to drive the piezoelectric element,
a connection switchover unit configured to selectively connect the piezoelectric element to the piezoelectric element drive unit,
a discharge circuit connected between the piezoelectric element and the connection switchover unit, and configured to discharge electric charge accumulated in the piezoelectric element, and
a control unit, the method comprising the steps of:
detecting a pressure load on a touch face of the touch sensor based on an output signal of the piezoelectric element and controlling the connection switchover unit, when the pressure load detected satisfies a standard to provide a tactile sensation, to connect the piezoelectric element to the piezoelectric element drive unit and controlling the piezoelectric element drive unit to drive the piezoelectric element such that the tactile sensation is provided to an object pressing the touch face; and then controlling the discharge circuit to discharge the electric charge accumulated in the piezoelectric element by controlling the connection switchover unit to connect the piezoelectric element to the control unit.