EP0368532A2
Expired / Lapsed
EP
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Electrical power control apparatus and methods
Assignee: Smiths Group PLC
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Filing: 1989-10-31
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Granted: —
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Expires: 2009-10-31
Abstract
Abstract Electrosurgery apparatus includes an r.f. power amplifier (10) with an output to a patient electrode (20) and a control unit (3). Power output voltage and current signals are supplied to A/D converters (34) and (35) to provide two digital signals that are used to address a look-up table in an EPROM (140) providing a digital output representative of impedance. Switches (44, 45) are set by the user to the desired mode/power curve and this provides a digital signal which together with the impedance signal (141) is used to address a second look-up table in an EPROM (142) which contains digital representations of the required output voltage of the amplifier (10) on line (53) to produce the desired power level. An adder (52) compares the required digital voltage (53) with the digital feedback of the actual voltage on line (51) to produce an error signal on line (54) that after being converted to analogue form is supplied to the amplifier (10) to control its output.
Inventors
- 👤 Timothy John Carder
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 04:21
CPC Classifications
A; A61; A61B; A61B18/00; A61B18/04; A61B18/12; A61B18/1206; A61B2018/00636; A61B2018/00696; A61B2018/00702; A61B2018/00773; A61B2018/00779; A61B2018/00827; A61B2018/00875; A61B2018/00892; Y; Y10; Y10S; Y10S128/00; Y10S128/908; Y10S323/00; Y10S323/911
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
150 words
Electrical power control apparatus including a power supply unit that delivers an alternating power output signal at a level that is controlled by an input signal to the power supply unit, characterised in that the apparatus includes a circuit (32-37) that derives a first digital signal representative of the voltage and current of the output signal, a device (43, 44) that derives a second digital signal representative of a performance characteristic of the apparatus, a store (142) including a plurality of storage locations each of which contains information for use in providing the input signal to the power supply unit (10), that the first and second digital signals together define the location of one of the storage locations such that as the output voltage, current or performance characteristic changes a different one of the storage locations is addressed and the input signal is varied accordingly to control the output signal.
Claim 2
Dependent Claim
150 words
Electrical power control apparatus including a power supply unit that delivers an alternating power output signal at a level that is controlled by an input signal to the power supply unit, characterised in that the apparatus includes a circuit (32-37) that derives a first digital signal representative of the voltage and current of the output signal, a device (43, 44) that derives a second digital signal representative of a performance characteristic of the apparatus, a store (142) including a plurality of storage locations each of which contains information for use in providing the input signal to the power supply unit (10), that the first and second digital signals together define the location of one of the storage locations such that as the output voltage, current or performance characteristic changes a different one of the storage locations is addressed and the input signal is varied accordingly to control the output signal.
Claim 3
Dependent Claim
26 words
Electrical power control apparatus according to Claim 1, characterised in that the device that derives the second digital signal includes a manually settable switch (43, 44).
Claim 4
Dependent Claim
21 words
Electrical power control apparatus according to Claim 1 or 2, characterised in that the first digital signal is an impedance signal.
Claim 5
Dependent Claim
65 words
Electrical power control apparatus according to Claim 3, including a second store (140) including a plurality of storage locations each of which contains information representative of the impedance signal, characterised in that the storage locations in the second store are addressed by a digital signal representative of the voltage of the output signal and a digital signal representative of the current of the output signal.
Claim 6
Dependent Claim
32 words
Electrical power control apparatus according to any one of the preceding claims, characterised in that the second digital signal is representative of the shape of the desired curve of power against impedance.
Claim 7
Dependent Claim
54 words
Electrical power control apparatus according to any one of the preceding claims including a comparator (52) that compares an output signal from the store (142) with a feedback signal from the output signal of the power supply unit (10), characterised in that the comparator (52) derives the input to the power supply unit (10).
Claim 8
Dependent Claim
41 words
Electrical power control apparatus according to Claim 6, characterised in that the comparator (52) provides an input to an alarm (58, 59), and that the alarm provides an alarm signal when the output of the comparator (52) exceeds a predetermined amount.
Claim 9
Dependent Claim
48 words
Electrical power control apparatus according to any one of the preceding claims, including a manually settable power level switch (43), characterised in that the input signal to the power supply unit (10) is adjustable according to the desired power level as indicated by the power level switch (43).
Claim 10
Dependent Claim
51 words
Electrical power control apparatus according to Claim 8, characterised in that the storage locations in the store (142) contain representations of the input signal at full power, and that the apparatus modifies the representations at full power according to the desired power level as indicated by the power level switch (43).
Claim 11
Dependent Claim
46 words
Electrosurgery apparatus including electrical power control apparatus according to any one of the preceding claims in which the supply unit (10) provides a radio frequency output, and a patient electrode (20) connected to receive the radio frequency power output signal from the power supply unit (10).
References Cited (Backward Citations)
No citation records indexed.
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