Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
  • A61N1/00—Electrotherapy; Circuits therefor
  • A61N1/02—Details
  • A61N1/08—Arrangements or circuits for monitoring, protecting, controlling or indicating
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
  • A61N1/00—Electrotherapy; Circuits therefor
  • A61N1/18—Applying electric currents by contact electrodes
  • A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
  • A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
  • A61N1/36014—External stimulators, e.g. with patch electrodes
  • A61N1/3603—Control systems

Definitions

• the invention relates to the field of health care, particularly to medical devices using electrotherapy as a physical medicine treatment method.
• Electrotherapy is a medical procedure used to treat a variety of diseases and health problems.
• the treatment employing the beneficial effects of electric energy uses direct or pulsating current.
• the devices are powered by batteries or from the power mains.
• the devices provide a high degree of safety in terms of their interaction with the power mains.
• the patient In the treatment procedure, the patient is connected to the circuit, in which some type of electrotherapy takes place.
• the current intensity and the length of procedures are individual.
• the polarity of current is switched over and the procedure is repeated with the reversed polarity.
• Procedures are ended by switching the device from the operating mode to the stand-by mode and subsequent disconnection of the patient from the circuit, to which he was connected.
• the purpose of the invention was to develop a regulation device for devices that use electrotherapy as a physical method of treatment so, that they would not cause electric shock to patients in case of accidental interruption of procedure.
• Electrotherapy uses direct current or pulsating current.
• This invention aims to ensure the patient does not suffer electric shock during the procedure in the event of accidental interruption of the procedure, such as taking out the hands from the water with electrodes when the device is in operation mode.
• the subject of the invention is a new design of the regulation device to prevent electric shock in devices using electrotherapy as physical method of treatment.
• the cause of given positive function of the device that it does not cause electric shock, is its ability to adapt, as an electric power source, to change of load impedance of the patient's body exactly when the patient removes the hands from the water with electrodes.
• the power source is a regulable source of direct current.
• the key factor is the relationship between the regulator and the regulated system - the loading impedance of the patient's body enjoying the treatment therapy.
• the parameters of the regulator which need to be adjusted in order to regulate the regulated system with zero or negligible regulation deviation, are the following: speed, reaction, response time, and inertia
• the load impedance of the patient's body, enjoying the treatment therapy as the regulated system has the following characteristics:
• the amount of the ohmic resistance varies in the range of about ⁇ 5%, i.e., relatively little and slowly
• the regulator of output current with the delay Treg consists of an output current stabilizer with a delay element, an amplifier of regulation deviation, a starting circuit, a circuit of gradual regulation of output current, and a switch of stand-by and operation modes of the device.
• the regulator solves as follows:
• the value of the output voltage is about 10V.
• the load - the patient's body is exposed to the current of about 2 mA, and the device switches to operation mode automatically.
• the voltage in the circuit further decreases to approximately 3V, and the current starts to rise slowly until it reaches the preset amplitude value.
• the current increase time is about 0 to 60 sec, depending on the pre-set amplitude value of current, i.e., shorter time for lower value and longer time for higher value.
• the medical procedure itself starts. After completing the procedure, the patient is disconnected from the circuit and the device automatically switches to standby mode. When the patient suddenly interrupts the procedure, i.e., unexpectedly pulls his hands from the water while the device is on, there will be a rapid rise in the current up to its nominal value, while regulator will respond to the rapid change by withholding its current value with the delay Treg. During this time, the device manages to switch to standby mode. Standby mode is identical to the state of the device after switching on. The device is ready to start further medical procedures.
• the regulator by its function completely eliminates electrical shock at the beginning and end of the procedure under meeting the following conditions between the delay Treg of the output current from the regulator block (4), the time Tvyp for quick switching of the device from operation mode to stand-by mode, and the time Trim of gradual regulation of the amplitude of the output current:
• This feature allows the patient to discontinue the procedure therapy at any time and resume it again without having to switch the device from operation mode to stand-by mode and vice versa.
• Figure 1 contains the block diagram of the medical device in which occurrence of electric shock is prevented during the procedure using electrotherapy.
• Figure 2 shows the block diagram of the regulator of output current with the delay.
• Figure 3 shows the electrical diagram of the regulator of output current with the delay.
• the regulation device for preventing electric shock in devices utilizing electrotherapy for treatment consists of stabilizer 7 of output current with a delay element, of amplifier 8 of regulation deviation, of starting circuit 5, of circuit 6 of gradual regulation of output current, and of switch 9 of operation and stand-by modes of the device.
• Stabilizer 7 of output current with a delay element allows to set a certain value of output current and to maintain that value independently on actual load parameters exactly at the time the patient removes the hands from the water with electrodes.
• the delay element "instantaneously" cancels this and creates a delay of response of the stabilizer in tenths of seconds.
• stabilizer 7 of output current with the delay Treg used transistor T2 connected to a common base.
• the voltage drop caused by the output current in resistors Rll and R26 and Schottky diode D18 is compared on base transition with the preset voltage of potentiometer JPl.
• the regulation deviation is conducted through resistor R16 to the input of the regulation deviation amplifier.
• Diode D15 linearizes the setting process by the potentiometer, and Zener diode D8 along with resistor R22 are used to stabilize it.
• Measurement error in standby mode is eliminated by the presence of emitter follower T13 and of input V2, which bridges diode D8 and produces zero bias of the base of transistor T2. After switching to operation mode, residual voltage is removed by Schottky diode D18 connected for the voltage in the reverse direction.
• Amplifier 8 of regulation deviation is made up of transistors T4 and T5. Amplifier 8 of regulation deviation is controlled by N-FET transistor T7, which limits its activity to operation mode of the source. In stand-by mode, amplifier 8 of regulation deviation is switched off by high resistance of channel T7. Using the input from the electrode, amplifier 8 of regulation deviation limits the maximum output voltage in electrodes of the device.
• Starting circuit 5 serves to switch the source from stand-by mode to operation mode and vice versa. It is formed by transistor T6 with a scanner circuit of output current with diodes D9 and D17 and resistors R12 and R25. Resistor R25 sets the amount of the switching current of both function modes.
• the Zener diode connected in the forward direction reduces the voltage drop on resistor R25 to about 0.6 V.
• Schottky diode D17 separates the base circuit of transistor T6 from delay element C12, C13, Rll.
• Output VI controls indication functions of the device.
• Circuit 6 of gradual regulation of output current is a charging RC member formed by high-capacity ceramic capacitors CIO, Cll and resistor R18.
• the time of gradual regulation of output current is roughly given by the RC constant of this circuit and here is approx. 60 sec. This time depends on the value of the set output current.
• the discharge circuit of capacitors CIO and Cl l is transistor T8, together with resistor R19.
• the start of regulation of output current is determined by closing transistor T8 by signal from the starting circuit.
• Switch (9) of stand-by and operation modes directly controls the control circuit of the switched-mode power source (3) of the device. This above given wiring is analogous to the regulation solution for the elimination of electric shock used in electrotherapy devices in case of accidental interruption of the procedure.
• the device using electrotherapy for treatment consisting of a power supply block (1), an indication block (2), and a switched-mode power supply block with feedback (3) connected to a regulator block (4) of output current with the delay Treg does not cause electric shock to patients in case of accidental disruption of the medical procedure.
• the presented regulation device is applicable in all devices or instruments, which use any kind of electrotherapy.

Landscapes

• Health & Medical Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• Public Health (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Radiology & Medical Imaging (AREA)
• Neurology (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Health & Medical Sciences (AREA)
• Heart & Thoracic Surgery (AREA)
• Veterinary Medicine (AREA)
• Electrotherapy Devices (AREA)
• Surgical Instruments (AREA)
• Catalysts (AREA)
• Continuous-Control Power Sources That Use Transistors (AREA)
• Emergency Protection Circuit Devices (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

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Citations (8)

Family Cites Families (3)

• 2013
  • 2013-03-09 CZ CZ2013-175A patent/CZ304552B6/cs unknown
• 2014
  • 2014-03-06 DE DE112014001207.6T patent/DE112014001207T5/de not_active Ceased
  • 2014-03-06 WO PCT/CZ2014/000025 patent/WO2014139486A1/en not_active Ceased
  • 2014-03-06 SK SK50059-2015A patent/SK288395B6/sk unknown
  • 2014-03-06 PL PL413855A patent/PL413855A1/pl unknown
  • 2014-03-06 GB GB1517424.6A patent/GB2530421A/en not_active Withdrawn

Patent Citations (8)

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