摘要:
A fatigue testing system provides simultaneous cycle testing for a plurality of prosthetic devices under simulated physiological loading conditions. A plurality of sample holders containing test samples of prosthetic devices is positioned between a distribution chamber and a return fluid chamber to form an integrated test chamber. A reciprocating linear drive motor operates a rolling bellows diaphragm to cyclically pressurize fluid within the test chamber and drive the pressurized fluid through the prosthetic devices being tested. The test chamber defines a return flow conduit in fluid communication with each of the sample holders, the return fluid chamber, and the distribution chamber. Compliance chambers and throttle valves associated with each of the sample holders regulate the pressure gradient and back pressure across the prosthetic devices being tested.
摘要:
A fatigue testing system provides simultaneous cycle testing for a plurality of prosthetic devices under simulated physiological loading conditions. A plurality of sample holders containing test samples of prosthetic devices is positioned between a distribution chamber and a return fluid chamber to form an integrated test chamber. A reciprocating linear drive motor operates a rolling bellows diaphragm to cyclically pressurize fluid within the test chamber and drive the pressurized fluid through the prosthetic devices being tested. The test chamber defines a return flow conduit in fluid communication with each of the sample holders, the return fluid chamber, and the distribution chamber. Compliance chambers and throttle valves associated with each of the sample holders regulate the pressure gradient and back pressure across the prosthetic devices being tested.
摘要:
A fatigue testing system provides simultaneous cycle testing for a plurality of prosthetic devices under simulated physiological loading conditions. A plurality of sample holders containing test samples of prosthetic devices is positioned between a distribution chamber and a return fluid chamber to form an integrated test chamber. A reciprocating linear drive motor operates a rolling bellows diaphragm to cyclically pressurize fluid within the test chamber and drive the pressurized fluid through the prosthetic devices being tested. The test chamber defines a return flow conduit in fluid communication with each of the sample holders, the return fluid chamber, and the distribution chamber. Compliance chambers and throttle valves associated with each of the sample holders regulate the pressure gradient and back pressure across the prosthetic devices being tested.
摘要:
A fatigue testing system provides simultaneous cycle testing for a plurality of prosthetic devices under simulated physiological loading conditions. A plurality of sample holders containing test samples of prosthetic devices is positioned between a distribution chamber and a return fluid chamber to form an integrated test chamber. A reciprocating linear drive motor operates a rolling bellows diaphragm to cyclically pressurize fluid within the test chamber and drive the pressurized fluid through the prosthetic devices being tested. The test chamber defines a return flow conduit in fluid communication with each of the sample holders, the return fluid chamber, and the distribution chamber. Compliance chambers and throttle valves associated with each of the sample holders regulate the pressure gradient and back pressure across the prosthetic devices being tested.
摘要:
Prostheses are fatigue tested using an apparatus under simulated physiological loading conditions. A fluid housing defines an entrance chamber having fluid outflow ports and an exit chamber having opposing fluid inflow ports and a central flow conduit in communication with the entrance chamber and the exit chamber. A plurality of housing tubes into which prosthesis are deployed may extend between the fluid outflow and inflow ports. Alternatively, tubular prostheses may be connected directly between the inflow and outflow ports. A reciprocating linear drive pump having a flexible diaphragm is provided to cyclically pressurize fluid through a common closed loop within the fluid housing and drive the pressurized fluid through the prosthesis being tested. The test system is capable of rotation independent of the motor drive for accurate diameter measurements of all test samples at elevated frequencies.
摘要:
Prostheses are fatigue tested using an apparatus under simulated physiological loading conditions. A fluid housing defines an entrance chamber having fluid outflow ports and an exit chamber having opposing fluid inflow ports and a central flow conduit in communication with the entrance chamber and the exit chamber. A plurality of housing tubes into which prosthesis are deployed may extend between the fluid outflow and inflow ports. Alternatively, tubular prostheses may be connected directly between the inflow and outflow ports. A reciprocating linear drive pump having a flexible diaphragm is provided to cyclically pressurize fluid through a common closed loop within the fluid housing and drive the pressurized fluid through the prosthesis being tested. The test system is capable of rotation independent of the motor drive for accurate diameter measurements of all test samples at elevated frequencies.
摘要:
System and method for controlling delivery of energy to divide tissue are disclosed. The system comprises an electrosurgical instrument having an electrically energizable cutting element which communicates electrical energy to the tissue and a generator to supply the energy to the electrosurgical instrument which supplies the energy to the tissue in a first pulse to react the tissue, in slow pulses to create a desiccation line until impedance at the tissue has reached a threshold, and in rapid pulses to divide tissue across the desiccation line.
摘要:
An end effector assembly for use with an instrument for sealing vessels and cutting vessels includes a pair of opposing first and second jaw members which are movable relative to one another from a first spaced apart position to a second position for grasping tissue therebetween. Each jaw member includes an electrically conductive tissue contacting surface connected to an electrosurgical energy source. At least one of the jaw members includes an electrically conductive cutting element disposed within an insulator defined in the jaw member. A rigid structural support is included which is configured to support the electrically conductive tissue sealing surface and includes at least one flow channel defined therein.
摘要:
An electrosurgical system is disclosed. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. The electrosurgical generator includes impedance sensing circuitry which measures impedance of tissue, a microprocessor configured to determine whether a tissue reaction has occurred as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid, and an electrosurgical instrument including at least one active electrode adapted to apply electrosurgical energy to tissue.
摘要:
Various safe switching mechanisms are provided for use with electrosurgical instruments which prevent arcing between the high-energy contacts as the high-energy source is activated. The switching mechanisms generally include a pair of high-energy contacts and a pair of activation contacts. An actuator is provided which initially engages the high-energy contacts in advance of engagement of the activation contacts to prevent arcing and subsequently disengages the activation contacts in advance of the high-energy contacts as the energy source is deactivated. A method of switching power to an electrosurgical instrument while avoiding damage to high-energy contacts is also disclosed.