Ultrasonic transducer with improved compressive loading

Claim 2

An ultrasonic device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising; a stack of alternating positive and negative electrodes and piezoelectric elements in an alternating relationship with the electrodes; a mounting device having a first end and a second end, the mounting device adapted to receive ultrasonic vibration from the stack and to transmit the ultrasonic vibration from the first end to the second end of the mounting device; and a bolt threadedly engaged with the mounting device comprising a surface substantially equivalent to the surface area of an individual piezoelectric element for applying compression forces to the stack, and an element having a first contact surface adjacent to the stack and a second contact surface adjacent to the bolt surface, wherein the second contact surface area is less than the first contact surface area.

Claim 3

The device of claim 1 wherein said element comprises a beveled surface defining the second contact surface.

Claim 4

The device of claim 1 wherein said element comprises a first and second beveled surface defining the second contact surface.

Claim 5

The device of claim 1 wherein the element is annular in shape.

Claim 6

The device of claim 1 wherein the element comprises at least two contact surfaces adjacent to the surface, wherein the surface area of the at least two contact surfaces is less than the first contact surface area.

Claim 7

An ultrasonic device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising; alternating annular positive and negative electrodes and annular piezoelectric elements in alternating relationship with the electrodes to form a stack having a longitudinal axis; a mounting device having a first end and a second end, the mounting device adapted to receive ultrasonic vibration from the stack and to transmit the ultrasonic vibration from the first end to the second end of the mounting device; and a bolt threadedly engaged with the mounting device along the longitudinal axis for applying compression forces to the stack, the bolt comprising a surface for applying compression forces, the surface having a surface area in an overlapping relationship with the stack; and an element having a first contact surface area adjacent to the stack and a second contact surface area adjacent to the bolt surface, the second contact surface area less than the first contact surface area.

Claim 8

An ultrasonic device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising; alternating annular positive and negative electrodes and annular piezoelectric elements in alternating relationship with the electrodes to form a stack having a longitudinal axis; a mounting device having a first end and a second end, the mounting device adapted to receive ultrasonic vibration from the stack and to transmit the ultrasonic vibration from the first end to the second end of the mounting device; and a bolt threadedly engaged with the mounting device along the longitudinal axis for applying compression forces to the stack, the bolt comprising a surface for applying compression forces, the surface having a surface area in an overlapping relationship with the stack; and an element having a first contact surface area adjacent to the stack and a second contact surface area adjacent to the bolt surface, the second contact surface area less than the first contact surface area.

Claim 9

The device of claim 6 wherein the element comprises at least two contact surfaces adjacent to the surface, wherein the surface area of the at least two contact surfaces is less than the first contact surface area.

Claim 10

The device of claim 6 wherein the element is annular in shape.

Claim 11

An ultrasonic surgical device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising: alternating annular positive and negative electrodes and annular piezoelectric elements in alternating relationship with the electrodes to form a stack having a longitudinal axis; a mounting device having a first end and a second end, the mounting device adapted to receive ultrasonic vibration from the stack and to transmit the ultrasonic vibration form the first end to the second end of the mounting device; and a first compression means for applying compression forces to the stack, and the compression means comprises a surface for applying compression forces, the surface having a surface area in an overlapping relationship with the stack; a second compression means disposed between the first compression means and the stack and comprising a first contact surface area adjacent to the stack and a second contact surface adjacent to the surface, the second contact surface area less than the first contact surface; a transmission rod having a first end and a second end, the transmission rod adapted to receive ultrasonic vibration form the transducer assembly and to transmit the ultrasonic vibration from the first end to the second end of the transmission rod; and an end effector having a first end and a second end, the end effector adapted to receive the ultrasonic vibration from the transmission rod and to transmit the ultrasonic vibration from the first end to the second end of the end effector.

Claim 12

An ultrasonic surgical device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising: alternating annular positive and negative electrodes and annular piezoelectric elements in alternating relationship with the electrodes to form a stack having a longitudinal axis; a mounting device having a first end and a second end, the mounting device adapted to receive ultrasonic vibration from the stack and to transmit the ultrasonic vibration form the first end to the second end of the mounting device; and a first compression means for applying compression forces to the stack, and the compression means comprises a surface for applying compression forces, the surface having a surface area in an overlapping relationship with the stack; a second compression means disposed between the first compression means and the stack and comprising a first contact surface area adjacent to the stack and a second contact surface adjacent to the surface, the second contact surface area less than the first contact surface; a transmission rod having a first end and a second end, the transmission rod adapted to receive ultrasonic vibration form the transducer assembly and to transmit the ultrasonic vibration from the first end to the second end of the transmission rod; and an end effector having a first end and a second end, the end effector adapted to receive the ultrasonic vibration from the transmission rod and to transmit the ultrasonic vibration from the first end to the second end of the end effector.

Claim 13

The device of claim 9 further wherein the second compression means comprises at least two contact surfaces adjacent to the surface, wherein the surface area of the at least two contact surfaces is less than the first contact surface area.

Claim 14

An ultrasonic device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising a stack of alternating positive and negative electrodes and piezoelectric elements in an alternating relationship with the electrodes and further defining a radial axis r and a longitudinal axis z and further comprising a compression means for applying compression forces to the stack, the compression means comprises a surface for applying compression forces, the surface having a surface area in an overlapping relationship with the stack, and an element having a first contact surface adjacent to the stack and a second contact surface adjacent to the surface, the second contact surface area is less than the first contact surface area; and wherein the stack is subjected in operation to compressive loading resulting in substantially uniform pressure along the r and z axes.

Claim 15

An ultrasonic device comprising: a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy, the transducer assembly comprising a stack of alternating positive and negative electrodes and piezoelectric elements in an alternating relationship with the electrodes and further defining a radial axis r and a longitudinal axis z and further comprising a compression means for applying compression forces to the stack, the compression means comprises a surface for applying compression forces, the surface having a surface area in an overlapping relationship with the stack, and an element having a first contact surface adjacent to the stack and a second contact surface adjacent to the surface, the second contact surface area is less than the first contact surface area; and wherein the stack is subjected in operation to compressive loading resulting in substantially uniform pressure along the r and z axes.

Claim 16

The ultrasonic device of claim 11 , wherein the element comprises at least two contact surfaces adjacent to the surface, wherein the surface area of the at least two contact surfaces is less than the surface area of the first contact surface.