RU2372871C1 - Gas feed unit for argon-plasma coagulation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medical equipment, namely to devices of gas feed to a medical tool in argon-plasma coagulation and aims at generation and maintenance of specified gas flow. A gas feed unit contains a processor, a flow sensor and series gas feed line, safety valve, electromagnetic ingate, high pressure reducer and gas flow regulator as an electrically controlled gas-spring reducer with an in-built mechanical valve. The input and exit of the gas-spring reducer are connected through two series secondary electromagnetic valves with their junction point being connected through a pneumatic throttle valve to the gas spring of the gas-spring reducer. The electromagnetic valves are controlled by the processor considering signal from the flow sensor.

EFFECT: application of the invention allows maintaining specified gas flow within wide range of excess pressure in gas feed to the tool.

2 cl, 1 dwg

Description

The invention relates to medical equipment, and in particular to methods of supplying gas to a medical instrument during argon-plasma coagulation, and is intended to create and maintain a given gas flow rate.

Two main gas supply methods are known. In the first regulating element are electromagnetic valves - valve method, in the second regulating element is an electrically controlled gearbox - reduction method. Consider these two methods on the example of the method of gas insufflation into the body cavity.

A device for implementing the valve gas supply method comprises a gas supply line, a high pressure reducer, an adjustable safety valve, an element in which the inlet solenoid valve, the outlet solenoid valve, and between them the gas volume, and also a logic device for calculating the pressure in the body cavity by at least at two points of pressure drop in the above gas volume and for monitoring the first and second solenoid valves, a pressure indicator controlled by a logic device, etc. the forming pressure value into an electrical signal and an apparatus for introducing gas directly into the body cavity. This method and device is described in US patent No. 5152745, M. cl. A61M 13/00, published on October 6, 1992.

A device is known for regulating a given tension of tapes, in which a pneumatic spring is used, acting on a spool distribution device that controls the pressure of the working fluid (AS No. 374581, G05D 15/00, published on 03.20.1973).

The disadvantage of this device, from the point of view of the tasks we set, is that the gas is released when the pressure in the pneumatic spring of this device drops into the atmosphere, and not into the working tool, which in our case would lead to an unreasonably high consumption of argon.

A device for implementing the gas supply reduction method comprises a gas supply line, a high pressure reducer, an adjustable safety valve, an inlet solenoid valve, an electrically controlled reducer, a flow sensor, a pressure sensor, and a microprocessor module. This method and device are described in patent RU No. 2175250, M. cl. A61M 13/00.

During argon plasma coagulation, it is necessary to maintain a continuous predetermined gas flow through the argon-reinforced handle-electrode - about 1-6 l / m and for an endoscopic probe about 1-1.5 l / m. In this case, the pressure at the inlet of the tool for the implementation of this flow rate should vary in the aisles of 0.05-1 atm. This allows you to make a valve method. Its disadvantage is the fact that the continuous operation of the gas requires constant operation of the electromagnetic valves, which leads to the rapid development of their resource. The gear method does not have this drawback, but it does not allow creating pressure at the tool inlet of the order of 1 atm. This is due to the fact that the electromagnet, which is included in the electrically controlled gearbox and is an electrically controlled spring, must create a force of the order of 20-30 kg, which is technically difficult to realize in small sizes and with low current consumption from the power supply.

The basis of the invention is the creation of a gas supply unit for argon plasma coagulation, which allows you to maintain a given gas flow rate in a wide range of excess pressure in the path of gas supply to the tool through the use of a gearbox with an air spring, which has a valve control system. This leads to an increase in the reliability of the device, a decrease in its energy intensity and a decrease in size.

The solution of the technical problem lies in the fact that in the gas supply unit, which contains a processor, a flow sensor, as well as a gas supply line, a safety valve, an inlet solenoid valve, a high pressure reducer that controls the gas flow, an element in the form of an electrically controlled reducer, for gas flow control was used a reducer with a pneumatic spring, which includes a mechanical valve, while the input and output of the reducer with a pneumatic spring are connected through cut two additional series-connected electromagnetic valves, the connection point of which is connected through a pneumatic throttle to the pneumatic spring of the gearbox with the pneumatic spring, and the electromagnetic valves are controlled by the processor by a signal from the flow sensor.

The reducer with a pneumatic spring is made in the form of two chambers separated by a membrane connected to a mechanical valve and equipped with gas supply devices.

The technical result is to increase reliability by increasing the life of the electromagnetic valves (which work only at the time of setting a predetermined flow rate, unlike the valve method) included in the gas supply unit. The reduction in energy consumption of the product compared with the gear method is due to the fact that significantly less energy is needed to control the valves than to control an electrically controlled gear. The ability to maintain a given gas flow rate in a wide range of excess pressure in the path of gas supply to the medical instrument is ensured by the fact that the air spring allows you to create the necessary efforts to create the necessary pressure drop on the medical instrument.

This invention essentially relates to the gear method and differs from analogues and prototype in that the electromagnet included in the electrically controlled gear is replaced by a known spring air spring with an original valve control system. And the introduction of a pneumatic throttle into the valve control system allows reducing the dimensions of the gearbox with a pneumatic spring in comparison with a gearbox with an electrically controlled spring.

The essence of the proposed method of gas supply is illustrated by the drawing, which shows a diagram of the gas supply unit, with all the connections connected to the processor 1 are electric, the rest are pneumatic.

The gas supply unit contains a gas supply line 2 (line or cylinder with argon), a safety valve 3, an inlet solenoid valve 4, a processor 1, a high pressure reducer 5, a reducer with an air spring 6, consisting of two chambers 6a and 6b, separated by a membrane, which mechanically connected with a mechanical valve 12, a flow sensor 7, a medical instrument 8, a pneumatic throttle 9, additional solenoid valves 10 and 11.

The device operates as follows. Gas through a gas supply line 2 with a pressure of 5 atm enters through a safety valve 3 to the inlet solenoid valve 4. When the gas supply unit is turned on, the inlet solenoid valve 4 opens with a signal from processor 1, the gas enters the inlet of the high pressure reducer 5, which reduces the pressure to 1.5 atm . From the output of the high pressure reducer 5, the gas simultaneously flows to the solenoid valve 10 and to the mechanical valve 12 (which is part of the gearbox with a pneumatic spring). The gearbox with air spring 6 consists of two chambers 6a and 6b, separated by a membrane. Gas enters through a mechanical valve 12, which is mechanically connected to the membrane, into the chamber 6a. From the chamber 6a, gas flows through a flow sensor 7 connected to the processor 1 to the medical instrument 8. To increase the gas flow through the medical instrument 8, the signal from the processor 1 opens the electromagnetic valve 10 and the gas flows through the air throttle 9 into the chamber 6b. The mechanical valve 12 opens only when the pressure in the chamber 6b (which essentially acts as a pneumatic spring) exceeds the pressure in the chamber 6a. Upon reaching the specified flow rate through the medical instrument 8, the signal from the flow sensor 7 enters the processor 1, which closes the solenoid valve 10. To reduce the gas flow through the medical instrument 8, the signal from the processor 1 opens the electromagnetic valve 11 and gas flows from the chamber 6b through the air throttle 9 to chamber 6a. When the desired flow rate is reached through the medical instrument 8, the signal from the flow sensor 7 is supplied to the processor 1, which closes the electromagnetic valve 11. After setting the desired flow rate, the valves 10 and 11 are closed, i.e. the rest of the time the valves do not work.

The present invention allows: to increase the life of electromagnetic valves (compared to the valve method) included in the gas supply unit, which leads to an increase in the reliability of the entire product, to reduce the energy consumption of the product compared to the gear method due to the fact that significantly less energy is needed to control the valves, than to control an electrically controlled gearbox. Due to the introduction of a pneumatic throttle, the dimensions of the gearbox with a pneumatic spring are reduced compared to a gearbox with an electrically controlled spring.

Claims (2)

1. The gas supply unit for argon plasma coagulation, which contains a processor, a flow sensor, as well as a series-connected gas supply line, a safety valve, an inlet solenoid valve, a high pressure reducer, a gas flow regulating element in the form of an electrically controlled reducer, characterized in that for regulation gas flow rate, a reducer with a pneumatic spring and a mechanical valve included in its composition was used, while the inlet and outlet of the reducer with a pneumatic spring are connected through va additional series connected solenoid valves, a connection point which is connected through flow controllers to a pneumatic spring with a pneumatic spring gear, and the solenoid valves is controlled by a processor on a signal from the flow sensor. 2. The gas supply unit according to claim 1, characterized in that the gearbox with a pneumatic spring is made in the form of two chambers separated by a membrane connected to a mechanical valve and equipped with gas supply devices.

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