High-intensity focused ultrasound device and method for controlling transducer moving piezoelectric device used in the same
A high-intensity focused ultrasound (HIFU) device and a method for controlling the transducer moving piezoelectric device achieve accurate and stable control as to movement of a transducer and a treatment position by use of a transducer moving piezoelectric device configured to have a compact size in accordance with a great reduction in the size of a handpiece.
1 . A high-intensity focused ultrasound device for providing ultrasound for treatment, comprising:
a handpiece body;
a cartridge comprising a printed circuit board (PCB) with a memory storing a plurality of sensing values, the cartridge detachably coupled and electrically connected to the handpiece body,
wherein the cartridge is filled with a fluid for generation of ultrasound and provided with a contact head at one side thereof to come into close contact with a skin of a subject to be treated;
a transducer that provides a high-intensity focused ultrasound for treatment in accordance with a high frequency signal;
a piezoelectric driving device provided in the fluid in the cartridge, wherein the piezoelectric driving device comprises:
a piezoelectric motor to generate piezoelectric ultrasound in accordance with the high frequency signal,
a piezoelectric vibrating shaft connected to the piezoelectric motor to generate ultrasonic vibration in accordance with the piezoelectric ultrasound generated by the piezoelectric motor,
a piezoelectric vibrated mover movably coupled to the piezoelectric vibrating shaft so that the transducer is coupled to the piezoelectric vibrated mover and the piezoelectric vibrated mover moves along the piezoelectric vibrating shaft in accordance with ultrasonic vibration by the piezoelectric motor to move with the transducer,
a driving frame fixed to a side of a body of the cartridge, the driving frame comprising
a frame body,
a driving unit coupling member provided at a first side of the frame body,
an operation support member provided at a second side of the frame body opposite the first side,
a first guide shaft and a second guide shaft, each of which has a first end fixed to the driving unit coupling member and a second end opposite the first end fixed to the operation support member, and
a body coupling hole and a plurality of engagement holes provided at the driving unit coupling member, wherein the piezoelectric motor is primarily coupled to the body coupling hole and is secondarily engaged with the plurality of engagement holes to firmly couple the piezoelectric motor with the driving unit coupling member, and
a magnet provided to an end of the piezoelectric vibrated mover,
wherein a plurality of magnetic field sensors is arranged on the PCB in a line along the piezoelectric vibrating shaft while being spaced apart from the magnet so as to detect a position of the transducer by detecting the magnet; and
a controller configured to:
transmit a signal to the piezoelectric motor to move the piezoelectric vibrated mover along the piezoelectric vibrating shaft,
control the piezoelectric motor to stop the piezoelectric vibrated mover at a stop position when a sensing value sensed by one of the plurality of magnetic field sensors generated during a movement of the piezoelectric vibrated mover reaches one of predetermined sensing values corresponding to a plurality of positions at which the transducer radiates, respectively,
control the transducer to radiate the high-intensity focused ultrasound at the stop position, and
control to repeat the ultrasonic vibration, the movement of the piezoelectric vibrated mover along the piezoelectric vibrating shaft, and the generation of ultrasound through the transducer so that the transducer sequentially radiates the ultrasound at the plurality of positions corresponding to the predetermined sensing values stored in the memory,
wherein the PCB is disposed at an outer surface of the cartridge and electrically connects with the controller when the cartridge is coupled to the handpiece body,
wherein the plurality of magnetic field sensors sense a magnetic field of the magnet,
wherein a signal sensed by each of the plurality of magnetic field sensors is transmitted to the controller, and
wherein the controller senses a position and the movement of the piezoelectric vibrated mover based on the signal sensed by the each of the plurality of magnetic field sensors and controls generation of the high frequency signal.
2 . The high-intensity focused ultrasound device according to claim 1 , further comprising a high frequency generator provided outside of the handpiece body.
3 . The high-intensity focused ultrasound device according to claim 1 , wherein the piezoelectric motor is coupled to the driving unit coupling member and the piezoelectric vibrating shaft, wherein a first end of the piezoelectric vibrating shaft is connected to the piezoelectric motor and a second end opposite to the first end of the piezoelectric vibrating shaft is fixed to the operation support member so that the piezoelectric vibrated mover is enabled to move with the transducer along the piezoelectric vibrating shaft between the driving unit coupling member and the operation support member in accordance with the ultrasonic vibration of the piezoelectric vibrating shaft.
4 . The high-intensity focused ultrasound device according to claim 1 , wherein the piezoelectric vibrated mover comprises:
an operating body;
a transducer coupling member at the operating body and coupled with the transducer; and
a driving core member surrounding the piezoelectric vibrating shaft and movable along the piezoelectric vibrating shaft,
wherein the piezoelectric vibrated mover further comprises:
a first slide groove formed at a first side of the operating body and the first slide groove fitted around the first guide shaft; and
a second slide groove formed at a second side of the operating body and the second slide groove fitted around the second guide shaft,
wherein the piezoelectric vibrated mover is guided by the first guide shaft and the second guide shaft for a stable movement of the piezoelectric vibrated mover.