Instrument for the coagulation and dissection of biological tissue and method for operating such an instrument

A method for operating an instrument (26) for the coagulation and dissection of biological tissue with a tool (29) including at least one cutting electrode (38), at least one first coagulation electrode (36), at least one second coagulation electrode (37), a cutting output (54) connected to the at least one cutting electrode (38), a first coagulation output (51) connected to the at least one first coagulation electrode (36), a second coagulation output (51) connected to the at least one second coagulation electrode (37), a switching unit (53) that is triggered by a triggering signal (A), which switching unit is configured to be switched between a first switching state and a second switching state and is connected to a supply connection (46) and to the cutting output (54), and including a first switch (32) and an evaluation connection (24), the method comprising the following steps:

• applying an evaluation signal (S) with first half-waves (S1) having one polarity and second half-waves (S2) having another polarity to the evaluation connection (24),
• evaluating whether the first switch (32) is in a conductive or blocking state during at least one of the first half-waves (S1),
• generating the triggering signal (A) for the switching unit (53) during at least one of the second half-waves (S2), depending on whether the first switch is in the conductive or blocking state during at least one of the first half-waves (S1).

An instrument (26) for the coagulation and dissection of biological tissue, comprising:

• a tool (29) including at least one cutting electrode (38) and at least one first coagulation electrode (36) and at least one second coagulation electrode (37),and
• an operating circuit (45) comprising:
• a cutting output (54) connected to the at least one cutting electrode (38), a first coagulation output (50) connected to the at least one first coagulation electrode (36), and a second coagulation output (51) connected to the at least one second coagulation electrode (37),
• a supply input (46), which provides a supply voltage (UV) or a supply current (IV) ,
• an evaluation connection (24), which provides an evaluation signal (S) having first half-waves (S1) of one polarity and second half-waves (S2) of another polarity ,
• an evaluation circuit (70) connected to the evaluation connection (24), which evaluation circuit comprises a manually actuatable first switch (32) and a triggering element (52) for the generation of a triggering signal (A), wherein the evaluation circuit (70) is configured to evaluate during at least one of the first half-waves (S1) whether the first switch (32) was actuated, and to generate the triggering signal (A) depending on the evaluation during at least one of the second half-waves (S2), and
• a switching unit (53) comprising at least one switch, the switching unit (53) configured to be actuated by the triggering signal (A), and which is configured to be switched between a first switching state and a second switching state and which is connected to the supply input (46) and the cutting output (54),
• wherein the first switch (32) and the triggering element (52) are serially connected in a first evaluation branch (75), wherein the first evaluation branch (75) is connected to the evaluation connection (24).

An instrument (26) for the coagulation and dissection of biological tissue, comprising:

• a tool (29) including at least one cutting electrode (38) and at least one first coagulation electrode (36) and at least one second coagulation electrode (37),and
• an operating circuit (45) comprising:
• a cutting output (54) connected to the at least one cutting electrode (38), a first coagulation output (50) connected to the at least one first coagulation electrode (36), and a second coagulation output (51) connected to the at least one second coagulation electrode (37),
• a supply input (46), which provides a supply voltage (UV) or a supply current (IV) ,
• an evaluation connection (24), which provides an evaluation signal (S) having first half-waves (S1) of one polarity and second half-waves (S2) of another polarity ,
• an evaluation circuit (70) connected to the evaluation connection (24), which evaluation circuit comprises a manually actuatable first switch (32) and a triggering element (52) for the generation of a triggering signal (A), wherein the evaluation circuit (70) is configured to evaluate during at least one of the first half-waves (S1) whether the first switch (32) was actuated, and to generate the triggering signal (A) depending on the evaluation during at least one of the second half-waves (S2), and
• a switching unit (53) comprising at least one switch, the switching unit (53) configured to be actuated by the triggering signal (A), and which is configured to be switched between a first switching state and a second switching state and which is connected to the supply input (46) and the cutting output (54),
• wherein the evaluation circuit (70) comprises a manually actuatable second switch (33) and wherein the manually actuatable second switch (33) is arranged in an evaluation branch (76), wherein the evaluation branch (76) is connected to the evaluation connection (24).