Title:
DULL-END ULTRASONIC CANNULA NEEDLE
Document Type and Number:
Japanese Patent JPH0751281
Kind Code:
A
Abstract:
PURPOSE: To reduce the force required for a user, and prevent the forward end of a trocar from damaging a patient's external tissue by providing a mechanism for judging the time of the penetration of the trocar through the tissue, and stopping the operation of a trocar. CONSTITUTION: A light source 70 made of a diode laser emits light to a splitter 71 and the light is divided into a reference beam and a hand piece beam. This hand piece beam coupled to an optical fiber 73 via a coupler 72 is reflected with an end mass body, and returns to a photo detector 77 via the splitter 75 under exposure to a frequency change due to the Doppler effect of the vibrating end mass body. The reference beam is also received by the photo detector 77 via a coupler 76 and modulated together with the hand piece beam. The reference beam thereby generates a beat frequency and is converted to a modulated electrical signal. This signal is sent to a frequency analyzer 78, and a load at the forward end of a trocar is judged on the basis of a Doppler travel identified via the beat frequency, and a control means 63 stops the trocar at a suitable load level.
Inventors:
JIEFURII JIEI BAITEKUNASU
Application Number:
JP12200494A
Publication Date:
February 28, 1995
Filing Date:
May 12, 1994
Export Citation:
Assignee:
ETHICON INC
International Classes:
A61B1/00; A61B17/34; A61B18/00; A61B17/32; (IPC1-7): A61B17/34; A61B1/00; A61B17/36
Attorney, Agent or Firm:
Heiyoshi Odashima
Next Patent: 曲形の木製枠材の製造方法