DD220227A1 - CIRCUIT ARRANGEMENT FOR ELECTRONIC CONTROL AND MONITORING OF A GAS HUMIDIFIER - Google Patents

Abstract

THE INVENTION CONCERNS A CIRCUIT FOR ELECTRONIC CONTROL AND MONITORING OF A BREATHING GAS HUMIDIFIER WHICH HAS A HEATING DEVICE CONNECTED TO TWO TEMPERATURE SENSORS BY A TEMPERATURE CONTROLLER, OF WHICH ONE TEMPERATURE SENSOR PATIENT NEAR AND THE OTHER TEMPERATURE SENSOR ARE CLOSELY HEATED. OBJECT OF THE INVENTION IS ELECTRONICALLY TO SET THE RESPIRATORY TEMPERATURE, TO INFORM THEIR HEALTH IMMEDIATELY, AND TO DISPLAY THIS INFORMATION BY LIGHTBAND INDICATOR. THE INFORMATION SHOULD ALSO INCLUDE LIMIT VALUE MONITORING INDICATED BY COLOR MARKING, OPTICAL AND ACOUSTIC WARNING. THIS IS REACHED THE FACT THAT THE TEMPERATURE CONTROL A MULTI-comparator circuit HAVING THAT ON AMPLIFIER AND measuring bridges WITH TEMPERATURFUEHLERN CONNECTED AND WITH AN OFF LIGHT EMITTER DIODE FORMED DIODES LINE IN CONNECTION IS THAT ON TRANSISTOR COMBINATION WITH A BLINK GENERATOR AND AN ALARM GENERATOR SIGNALVERKNUEPFT IS.

Description

Circuit arrangement for the electronic control and monitoring of a respiratory gas humidifier

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Field of application of the invention:

The invention relates to ¹ a circuit arrangement for the electronic control und'Überwachü'ng a humidifier, the electrical heater is controlled by a controller via a patientemah disposed temperature sensors, "Atemgäsbefeuchter intended for the artificial patient ventilation and are constructed so that the patient end of the Ätemgasleitung , ie at the patient's entrance, the humidified and tempered respiratory gases have a relative humidity of 96 to loo % . ^! ^

Characteristic of the known technical solutions:

It is a device for the supply of patients with moist air is known in which by a sensor signal applied by the temperature controller, the amount of heat emitted by the heating element to the breathing gas line is controlled so that the end of the temperature: lower and the relative humidity

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is greater than the temperature and the relative humidity in the .. Evaporation chamber λ (DE-OS 23 45 677) · This gas heating and ^:. Humidification of the respiratory gas also realizes a breathing gas humidifier of the bubbler type, in which the dry respiratory gas is injected into a heatable water bath and the temperature sensor of the regulator zur.Regelung the heating cable supplied as a function of the outlet temperature of the moistened and tempe- ¹ . rationed gas in the patient-side end of the tube is arranged (DE-PS 25 12 6o7). It is also possible to have a respiratory gas humidifier with an evaporator arranged in the housing, which can be located below a water surface with a heating cartridge boiling the water and above with a water tank.

"" .. mer provided. At this a Atemgaszuführleitung and "a Atemgasabführleitung is connected, in the immediately behind the 'evaporator, a superheater is installed, the heating element is also controlled by a just before the Munstück arranged for the patient temperature sensor (DE-PS 27 o2 674) · Fernerhin an evaporation humidifier with a insulated from the liquid container heating element · is known, which is electronically controllable and provides respiratory gases to the patient with a relative humidity of loo % at a temperature of about 25 to 4o degrees G (DE-OS 28 32 225) continuous flow between 1 and about 60 liters per minute and the maximum inspiratory flow

amount to about 10 to 10 liters per minute, the pressure drop in the humidifier is approximately 1 cm of water column at a continuous flow rate of 3o liters per minute.

Again, this solution assumes that respiratory gas humidifiers may generally be atomizing or atomizing devices, bubble humidifiers or evaporative humidifiers, the latter of which are most widely used for their proven benefits. The advantages Lie <gen particularly in de r ^s reach higher moisture per unit volume, without producing water droplets. The reason given is that water droplets not only cause traumatic

effect "in weakened patients ^ but also represent a carrier for microorganisms in the ventilator ·, '

Be _r i a Verdampfüngsbefeuchter its kind · -is a humidification chamber with vaporizing element provided, of which the chamber is tightly surrounded by a heating element or provide the vaporization unit with a heating element either. This is preferably equipped with an electronic control to the temperature of the heat transfer surface. To monitor and turn off the evaporator humidifier when the temperature exceeds a predetermined level · This object to be solved by the electronic control promotes that the temperature sensor is fixed directly to the heating element to enable the electronic controller to cycle electrically To turn off and on the heating element input during shorter time intervals to control the temperature within narrow limits. However, the arrangement of this .Temperaturfühlers does not exclude that for the near-patient measurement of the temperature of the breathing gas, a further sensor, such as a thermistor is necessary to have the same time to exercise a watch function and off when exceeding the preset temperature levels, the heating element. With the introduced through this sensor shutdown: an acoustic and optical alarm system be "at the same time makes lifting the secured at the heating element temperature sensor and the close to the patient mounted sensors as a further _protection. Medium or a thermal fuse is provided, which is actuated in case of excessive temperature increase and Such safety for the patient is also at the forefront with another heatable humidifier, where overheating in the system triggers a visual and audible alarm, and also with this alarm the heater of the respiratory gas humidifier is automatically cut off (Prospectus of the 3 M Germany GmbH for breathing gas humidifier type 32 o4 G) .The device designed for a wide range of applications, however, has the further advantage that a

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optical indication of the proximal airway temperature is ensured by a digital display. And yet the respiratory gas humidifiers developed so far could only be satisfactory if, in addition to the gradual adjustment of the respiratory gas temperature in the respiratory physiologically required range and; for the optically clear display of the respiratory gas temperature at the patient's entrance, an overshoot and undershoot of the operating range of the respiratory gas temperature is displayed, · if defects and misuse operations - even with the ventilator connected - can be signaled.

Object of the invention:

The aim of the invention is to make these no.ch functions missing, realizable, to achieve an even better temperature information and to optimally shape the information monitoring of the adjacent respiratory gas temperature near the patient. -. .. '

Explanation of the essence of the invention j

The object of the invention is to develop a circuit arrangement for the electronic control and monitoring of a respiratory gas humidifier, which allows a gas temperature to be set electronically and its preselected height. immediately, is informed that this temperature information is carried out by means of a luminous band display and a limit value monitoring or • undershooting is indicated by color coding and! that a continuous monitoring of the evaporator temperature at the 'heat transfer surface, is secured by an overshoot, the permissible limit on the one hand recognizably displayed and on the other hand warned visually and acoustically · .-.

According to the invention, this object is achieved in that the temperature controller connected to the electrical heating device has a multiple-comparator circuit provided with a voltage divider, which has a first amplifier and a first amplifier

Constant current-fed measuring bridge with a near-patient arranged temperature sensor and a second amplifier and a second constant-current measuring bridge with a near-heater temperature sensor 'is connected, that this multiple comparator circuit is connected to formed as light emitting diodes diode array, directly to a temperature selector, to a transistor combination and are connected to a further Transistorkombinaticn, which are on the one hand via the "measuring bridges with the temperature sensors and on the other hand with the Ausgangstran'sistor connected to the heater optocoupler, with a.Blinkgenera-gate and with a Älarmgenerator signal-linked., '

In the circuit arrangement according to the invention is in an advantageous arrangement of the multiple comparator circuit on the one hand with the flash generator and a transistor and on the other hand .mit. ein connected to this transistor, signalv.erknüpf th light emitting diode, in turn, has a connection with the second measuring bridge and the second amplifier.ι It is particularly advantageous if the light emitting diodes known LED modes are used by their line array with light bands make different color coding.

In a further embodiment, the multiple comparator circuit is signal-linked to a transistor via which a terminal is once made with a gate connected to the flasher generator and on the other with diodes and via this with the one light-emitting diode. Another signal link is for the shutdown of. Heating device provided by the connected to the one transistor combination .Alarmgenerator input side is connected to a diode · For switching off the heater is the further possibility via a line which is performed by the first amplifier directly to those transistor combination, which in signal connection with the downstream of her Transistor and the optocoupler stands ·

Embodiment:.

The invention will now be described and illustrated in the drawings.

As can be seen, the circuit arrangement for the electronic control and monitoring of a breathing gas humidifier consists of a first amplifier 1, a second amplifier 2, a multi-phase comparator circuit 3 connected to these amplifiers 1, 2 and two bridge resistors 4 connected upstream of the amplifiers 1, 2 , 6 and a voltage divider 5 connected to the multiple comparator circuit 3 · on the output side of this voltage comparator

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Transistor circuit 3 are transistor combinations, which are designated by the reference numbers 7/1 »7/2 and'8 / 1, 8/2 and another transistor 9, 'of a direct An-" to the multiple comparator circuit .3 This multiple comparator circuit 3 is still connected to a flashing generator Io and via the transistor combination 8/1 to an alarm generator 11. In addition, the multiple comparator circuit 3 with its outputs (4 to 15, 18) is connected to a light emitting diode 12/1, and two light emitting diode combinations Ϊ2 / 2, 12/3 », all of which are implemented together as a series of light emitting diodes - The diode combinations 12/2, 12/3 with the transistor combination 8/1 directly and via a temperature selector switch 17 with the transit ¹ storkombination 7/1 are signal-linked. The latter is connected to the transistor combination 7/2 in combination, which in turn is connected to the output transistor of an opto-coupler 14. The reference numeral 15, the temperature sensor for the breathing gas temperature and the reference numeral 16 of the temperature sensor for the heating temperature is characterized by means of the bridge resistors 4, 6 to a certain temperature value or. , Voltage value are set. As can also be seen from the drawing, between the one output (4) of the multiple comparator circuit 3 there is still a connection to the transistor combination 8/1 and over

this to the transistor 8/2, which is signal-linked with a relay 13 and a diode 18. In addition, a diode 19 and two diodes 2o connected to a constant-current measuring bridge 23, in which the temperature sensor 15 is located and which amplifies the amplifier 1 with its output voltage · Likewise, the temperature sensor 16 is located in a measuring bridge 24 »whose output voltage in the amplifier. 2 is reinforced. Finally, the amplifier 1 is guided via a line 22 directly to the transistor combination 7/1 and the multiple Komparatorschalt- _λ 3 via an output (2) with the flashing generator Io and.a transistor 21 which in turn connected to the light emitting diode 12th / 1 is connected. The flashing generator Io is also activated by a gate 25 if there is an overshoot or undershoot of a reference voltage. For this purpose, one upper limit (OGW) input is connected to transistor .8 / 2 and the other lower limit input (UGW) is signal connected to transistor 9 <>

For the light emitting diodes or diode rows 12/1, 12/2 and 12/3 and ^ for the diode 19- preferably so-called LDE diodes are used, of which the designated by the number 12 can be designed as a light strip whose colors, for example, yellow for the light emitting diode 12/1, green for the light emitting diode 12/2 and red for the light emitting diode 12/3 .. Further features and advantages of the invention and existing signal links of the circuit arrangement will become apparent from the following functional description in conjunction with the drawing of the embodiment.

The illustrated circuit arrangement has shown that the temperature sensor 15 responsible for the respiratory gas temperature lies in a constant-current-fed measuring bridge 23 whose output voltage is amplified in the amplifier 1 and whose output signal is fed to the multi-compartment comparator circuit 3 via its input (17). In addition, 5 voltage references for the comparators of the multiple comparator circuit 3 are provided by the voltage divider, which rest against the inputs (3,16). It has also been shown

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that the outputs '(4 to 15) are connected to the light emitting diodes 12/2, 12/3' and have a connection to the temperature selector switch 17 * Upon reaching the temperature set by the temperature selector 17 temperature of the corresponding comparator tilts and an electric current flows via this temperature selector switch 17 to, transistor combination 7/1 · This controls via the transistor combination 7/2 the output transistor of the optocoupler 14 without power, whereby the connected heater (not shown) is turned off. This will also extinguish the diode 19 », which previously indicated heating operation ·

The multiple-comparator circuit 3 is formed by wiring of its outputs (14, 15) is set at a defined potential in the operating mode "band operation", whereby the light emitting diodes have been 12/1, 12/2, 12/3 designed as a luminous band _β In the operating temperature range, a flow electric current through the diodes 2o and the. Light emitting diodes 12/2 in the multi-comparator circuit 3 to the output of the not yet tilted stage, with the result that the green band lights and indicates the Atemgastemperatür. When falling below the reference voltage for the lower limit of the flash generator Io is activated starting from the output (15) of the multiple comparator circuit via the transistor 9 and the gate 25, which drives the transistor 21 with its output signal and thus via the diodes 2o and the light emitting diode 12 / 1 causes them to flash in the intermittent current flow. When the reference voltage for the upper limit value is exceeded, starting from the output (4) of the multiple comparator circuit 3 via the transistor combination "8/1 the following events are triggered:.

- The transistor 8/2 activated via the gate 25 the flashing. generator ^ lo, the ¹ via the terminal (2) of the multiple

Comparator circuit 3, the entire light emitting diodes ^ö or diode rows 12/2, 12/3 can flash; _. ·

- The alarm generator 11 with its signaling device is activated directly;

- Via the diode 18, the transistor 7/2 is turned off, which shuts off the heater;

- The relay 13 is turned on, which allows with its potential-free contact a signal output to external monitors ·. , :

The responsible for the heating temperature temperature sensor is set as shown with the bridge resistor 6 to a fixed temperature or »voltage. When exceeded, an electric current flows from the amplifier 2 to the transistor combination 8/1 and generates about the same signals as when exceeding the upper limit. ,

When ni, cht connected temperature sensor 15, the measuring, bridge 23 is so detuned that the output signal from the Vejr-. stronger 1 via the line 22 directly controls the transistor combination '7/1 and turns off the heater 7/2 and the optocoupler · 14 the heater.

With this circuit arrangement and the integrated Mehrfac.h comparator circuit 3 and the use of light emitting diodes 12/1, 12/2, 12/3 at its outputs (4 to 15 »18) is the direct connection ^ a temperature selector switch 17 for setting respiratory gas temperatures as well as immediate information about the prevailing respiratory gas temperature has become possible. Furthermore, given by the setting of the multiple comparator circuit 3 in "band operation" an embodiment of the individual LED diodes as light strip and produced by the color coding of the light band clear temperature information at limit exceeded by the blinking diode chain of light emitting diodes 12/2, 12/3 the optimal information quality is underlined. Another advantage is the combination of the bridge resistor 6 with the temperature sensor 16, whereby a low-inertia signaling is ensured when exceeding the limit temperature of the heater, for example _{on the} evaporator jacket of Atemgasbe humidifier »Inventive., Can thus a neat display and accurate adjustment of the breathing gas temperature in the respiratory physiologically necessary area.

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If the temperature exceeds or falls below the operating range of the breathing gas temperature, whether caused by defects or faulty operation, a reliable signalization and warning is issued. The warning of exceeding a fixed limit temperature is visually and acoustically warned and commissioning is not activated - closed gas temperature sensor or wire break refused, -

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Claims (6)

- '' - Ii -. Claim to the invention:. ... ........ ι 1. Circuit arrangement for the electronic control and monitoring of a Atemgasbefeucht, ers, the electrical heating 'device is connected via a temperature controller with two temperature sensors, of which a temperature sensor; close to the patient and the other temperature sensor is arranged close to the heating, characterized in that the temperature controller comprises a multiple-comparator circuit (3) provided with a voltage divider (5), which is connected via a first amplifier (1) and a constant-current measuring bridge (23). connected to the near-patient temperature sensor (15) and via a second amplifier (2) and a second constant-current measuring bridge (24) connected to the near-temperature sensor (16) and is in communication with a diode array formed from light emitting diodes (12/1 , 12/2, 12/3)> which are connected directly to a temperature selector switch (17) »to a transistor combination (7/1, 7/2) and to a further transistor combination (8/1, 8/2), which on the one hand via the measuring bridges (23, 24) with the temperature sensors (15, 16) and on the other hand with the output transistor of an opto-coupler (14) connected to the heating device (2 6), with a flash generator (lo) and with an alarm generator (11) are signal - linked ·. ._._-- '. 2. Circuit arrangement according to item 1, characterized in that the multiple-rKomparatorschaltkreis (3) on the one hand with the flash generator (lo) and a transistor (21) and on the other hand with a signal to the transistor (21)  , 'Light emitting diode (12/1) is connected in turn has a connection with the measuring bridge (24) and the amplifier (2). '. . 3 · Circuit arrangement according to item 1 and 2, characterized in that 'the light emitting diode (12/1) and the diode rows formed as light emitting diodes (12/2, 12/3) known. - 12 -     - 12 -...... ·. '. LED diodes are, which form by their line array light bands with different color coding ". In 4 "Circuit arrangement according to points 1 to 3» - by the fact that the multiple comparator circuit (3) is signalverknüpft with a transistor · (9), on / to a connection again with a with the flashing generator (lo) connected to gates (25) , and on the other with diodes (2o) and via these with the light emitting diode (12/1) is made. , , ''. 5 · Circuit arrangement according to items 1 to 4 »marked ϊ "''·      " in that the alarm generator (11) connected to the transistor combination (8/1, 8/2) is connected on the input side to a diode (18) signal. . ' 6 "circuit arrangement according to point 1 to 5» characterized da-, by that the amplifier (1) via a line (22) directly to the transistor combination (7/1) is guided, which in signal connection with the transistor (7/2) and the optocoupler (14) For this a sheet drawing