DE102012218754B4 - Method for operating a cleaning machine - Google Patents

Abstract

Method for operating a cleaning machine (1) from an elongated instrument (2), in particular an endoscope, having a channel (18), the channel (18) having an inlet (7) and an outlet (8), a compressed air connection (6) is provided at the inlet (7) of the channel (18), with the following process steps: Feeding compressed air to the input (7) of the channel (18), whereby a supply pressure level (20) of the compressed air is achieved by switching on or off a compressed air supply (10 , 11, 15) is changed, - measuring the pressure in front of the inlet (7) or in the inlet (7) of the channel (18) over a first predeterminable time (t) and - determining a permeability parameter of the channel (18) and / or Determining the tightness of the channel (18) or the compressed air connection (6) on the channel (18), characterized in that to determine the permeability parameter of the channel (18) and / or the tightness of the channel (18) or the compressed air connection (6) on the channel (18) a Spru The response (21, 22) to the change in the supply pressure level (20) is measured and analyzed, and the analysis includes determining a slope and / or forming a second derivative of the measured pressure (P) with respect to time.

Description

The invention relates to a method for operating a cleaning machine from an elongate instrument having a channel, in particular an endoscope, the channel having an inlet and an outlet, a compressed air connection being provided at the inlet of the channel, and compressed air being supplied to the inlet of the channel and changing a supply pressure level of the compressed air by connecting or disconnecting a compressed air supply, wherein the pressure before the entrance or in the entrance of the channel over a first predetermined time is measured and a permeability parameter and / or the tightness of the channel or the compressed air connection is determined on the channel ,

In cleaning machines or processing machines of a longitudinal instrument having a channel, for example an endoscope, in particular of a flexible endoscope, it is usually monitored whether the endoscope channels or the endoscope channel is or is correctly connected to the machine and whether the hygienic result is necessary Consistency is given. If a deviation from the setpoint is detected, the reprocessing process or the cleaning process is aborted with a corresponding error message. In this case, the user has the task of correcting the error. This takes place depending on the defect image, for example by brushing the affected endoscope channel or attaching a connection or adapter to the endoscope.

For channel monitoring, for example, as in EP 0 709 056 B1 is described, worked with flow sensors or pressure sensors, the flow or pressure characteristics of a liquid flushing medium z. B. Monitor water. This has the disadvantage that an error message can be made at the earliest after the first water intake, which takes a relatively long time. In addition, the run-in process water must be pumped out again before a correction of the error by the user is possible. In addition, the water consumption is also higher. The endoscopes or elongated instruments, preferably surgical instruments, usually have not only one channel but several channels which are to be cleaned or processed.

EP 0 709 056 B1 discloses a cleaning device for endoscopes in which a tightness measurement is performed by applying a predetermined and constant pressure to the endoscope. If the pressure falls by a certain value within a predetermined period of time, this is interpreted as an indication of a leak.

US 2005/0056081 A1 shows another device for cleaning an endoscope. To test the tightness of the endoscope, including the connected connections, the system is pressurized and closed with the aid of a valve. The subsequently measured time-dependent differential pressure between the outlet pressure and the actual pressure within the closed system is evaluated. If a pressure drop occurs that exceeds a predetermined value, this indicates a leak.

DE 10 2008 026 445 A1 discloses a method for testing the patency of an endoscope channel in an endoscope washer. The endoscope channel is flooded with cleaning fluid, which is acted upon by a series of pressure pulses. Maximum and minimum values of fluid pressure at the entrance of the channel are determined. These give an indication of the permeability of the channel.

It is an object of the present invention to provide an efficient and resource-saving method for operating a cleaning machine from a longitudinal instrument having a channel, in particular an endoscope.

• – Zuführen von Druckluft zu dem Eingang des Kanals, wobei ein Zuführdruckniveau der Druckluft durch Zuschalten oder Abschalten einer Druckluftversorgung verändert wird,
• – Messen des Drucks vor dem Eingang oder im Eingang des Kanals über eine erste vorgebbare Zeit und
• – Bestimmen eines Durchlässigkeitsparameters des Kanals und/oder Bestimmen der Dichtigkeit des Kanals oder des Druckluftanschlusses an dem Kanal,

wobei das Verfahren dadurch fortgebildet ist, dass zur Bestimmung des Durchlässigkeitsparameters des Kanals und/oder der Dichtigkeit des Kanals oder des Druckluftanschlusses an dem Kanal eine Sprungantwort auf das Verändern des Zuführdruckniveaus gemessen und analysiert wird und die Analyse das Bestimmen einer Steigung und/oder das Bilden einer zweiten Ableitung des gemessenen Drucks nach der Zeit beinhaltet.This object is achieved by a method for operating a cleaning machine from a longitudinal instrument having a channel, in particular endoscope, the channel having an input and an output, wherein a compressed air connection is provided at the entrance of the channel, with the following method steps:

• Supplying compressed air to the inlet of the channel, wherein a supply pressure level of the compressed air is changed by connecting or disconnecting a compressed air supply,
• Measuring the pressure in front of the input or in the input of the channel for a first predeterminable time and
• Determining a permeability parameter of the channel and / or determining the tightness of the channel or of the compressed air connection on the channel,

the method being developed in that for determining the Transmission parameters of the duct and / or the tightness of the duct or compressed air port on the duct are measured and analyzed for a step response to changing the supply pressure level and the analysis involves determining a slope and / or forming a second derivative of the measured pressure with time.

In addition, the object is achieved by a generic method, which is developed in that for determining the permeability parameter of the channel and / or the tightness of the channel or the compressed air connection to the channel, a step response to changing the feed pressure level is measured and analyzed and the analysis of a Duration, amplitude and / or wavelength of a vibration of the measured pressure includes.

By the invention, the channel monitoring is not performed with a rinsing liquid, but by applying the channel or the channels with compressed air, which is often already available for drying in corresponding cleaning machines. The measured pressure or the compressed air level indicates whether the duct is correctly connected to the machine or not. Thus, in addition, an unconnected or blocked endoscope channel can already be detected parallel to an automatic leak test. Usually, in the prior art, a leak test is first carried out with compressed air in order subsequently to check with a rinsing liquid, for example water, whether the endoscope channel is continuous. Thus, according to the invention, the leak test and the patency test can be performed simultaneously. As a result, the time to error detection is significantly reduced, which optimizes the process flow in a hospital, for example. In addition, resources can be saved in the event of a fault, which would otherwise cause costs.

In particular, the method is also suitable for checking several channels simultaneously or in succession. For this purpose, for example, a connecting device may be provided which, for example, in 4 of the EP 0 709 056 B1 is shown. In this case, for example, six channels can be checked in parallel, ie at the same time, for blockages, ie for permeability and tightness.

Preferably, changing the supply pressure level is step-shaped. In this respect, for example, it is a step function of the pressure level over time. Changing the Zuführdruckniveaus done so especially abruptly. This can be achieved by, for example, turning on or off a pump providing the pressure level, or opening or closing a valve located downstream of the pump but upstream of the duct. When the compressed air supply is connected to the input of the channel with the connection, a corresponding air pressure for the time is provided as the compressed air supply is switched on. When switching off or switching off the compressed air supply, no additional compressed air is supplied. In particular, if the channel and the connection to the channel are sealed and, in addition, the output of the channel would be obstructed, this means that then the compressed air in the channel would remain at a constant level. In the context of the invention, however, the output of the channel is preferably kept open to allow a flow of compressed air.

The term "supply pressure level" is to be understood in particular as meaning that a pressure level which is at a constant level above the ambient pressure, for example at 1 bar or 1.25 bar above the ambient pressure, is provided at the inlet of the channel, in particular in steps. This can be achieved by turning on or off a pump. Alternatively, a valve can be easily opened or, if the pressure level is reduced stepwise, for example, the valve can be closed, so that the present downstream of the valve pressure level can be done only by flowing away the compressed air to the output or leaks.

To determine the transmission parameter of the channel and / or the tightness of the channel or the compressed air connection of the channel, according to the invention a step response to the changing of the supply pressure level is measured and analyzed. In this case, in particular, the step response is understood to be a positive step response or a negative step response. A positive step response is, in particular, the progression of the pressure over time due to the increase in the feed pressure level, in particular the stepwise increase of the feed pressure level, for example from 1 bar to 2.2 bar total pressure, ie from 0 bar to 1.2 bar differential pressure to the environment. In particular, a negative step response is the measured pressure over a period of time due to a decrease in the supply pressure level, particularly a stepwise decrease in the supply pressure level, for example from 2 bar to 1 bar. With a positive step response, a static pressure will set after a certain time and a settling of the pressure, which, if the connection to the channel is dense and the channel is dense and also no clogging, for example by foreign bodies, due to an expected flow resistance in the channel, which is essentially given by the diameter of the channel. If, for example, the channel is not tight or the connection to the channel is not tight, a lower pressure will set than expected due to the physical conditions of the channel in the nominal state. With a blockage or a narrowing of the channel, a higher static pressure will set after a certain time.

For this reason, the analysis preferably includes a comparison of a static pressure with a first value that can be specified for the channel. This is especially true for a positive step response.

The analysis preferably includes the formation of an integral of the measured pressure over a second predefinable time and a comparison with a second value predeterminable for the channel, in particular with a negative step response. Due to the integral of the measured pressure over the second predetermined time, a flow resistance of the channel can be determined and thus the presence of a blockage, the presence of a leaky connection and further information. In particular, this analysis is performed on a negative step response. The inventive method comprises determining a slope and / or forming a second derivative of the measured pressure over time. Namely, the steeper the drop in pressure at a negative step response, the lower the flow resistance of the channel. In this way, the flow resistance of the channel can also be determined on the basis of this value or these values, which are preferably determined, and compared with a predeterminable flow resistance.

Also according to the invention, a method is alternatively specified in which the analysis of a duration, amplitude and / or wavelength of a vibration of the measured pressure is performed. In particular, an oscillation exists at the beginning of the step response and can be used to detect, for example, the amplitude of the oscillation or the frequency of the oscillation, a blockage and even the approximate location of the blockage to indicate to the cleaning personnel where in the channel the obstruction or contamination prevails. About the frequency or the distance of the maxima and minima of the vibration can be determined by the speed of sound in the compressed air medium, the distance between the sensor and the foreign body. The speed of sound is determined, for example, by the formula

Here, c is the speed of sound, P the pressure and p the density of the compressed air.

By measuring the compressed air level or compressed air level in the not yet steady state, a very accurate analysis of the tightness or contamination of the channel or the connection to the channel can be performed.

The method steps are preferably carried out before a, in particular first, flushing of the channel with a liquid. Thus, the process steps are performed immediately after inserting the instrument in the cleaning machine before a first rinse takes place with a liquid. As a result, liquid is saved.

In the context of the invention, analysis or analysis of a step response also means the comparison of a measured curve of the pressure over time with predeterminable curves or stored curves. In particular, in a control device of the cleaning machine for various elongated instruments to be cleaned, in particular endoscopes, the corresponding parameters or first and second values or curves for different channels of an endoscope or different endoscopes are stored in order to enable a comparison with the corresponding values or curves , Limit values may also be provided for the respective channels or each different channel, which, if they are exceeded or undershot, detects an imperfection or lack of tightness of the channel, the connection of the channel and a corresponding blockage of the channel.

In the context of the invention, the measured pressure or set pressure is, in particular, a differential pressure to the environment.

Further features of the invention will become apparent from the description of embodiments according to the invention together with the claims and the accompanying drawings. Embodiments of the invention may satisfy individual features or a combination of several features.

The invention will be described below without limiting the general inventive idea by means of embodiments with reference to the drawings, reference being expressly made to the drawings with respect to all in the text unspecified details of the invention. Show it:

1 a schematic view of a cleaning machine,

2 a schematic representation of a pressure profile when switching a compressed air source and

3 a schematic pressure curve when switching off a compressed air source.

In the drawings, the same or similar elements and / or parts with the same Reference numerals provided so that is apart from a new idea.

1 schematically shows a cleaning machine 1 into which an endoscope 2 is introduced. The endoscope 2 has a channel to be cleaned 18 on, the first is to check for impurities or is to check whether the hose connection 16 properly with the connector 6 to the entrance 7 of the canal 18 connected.

To check the tightness of the channel 18 , the tightness of the connection to the channel 18 or to check the continuity of the channel 18 , ie if there is no contamination in the channel 18 present, compressed air is from the entrance 7 through the channel 18 to the exit 8th of the canal 18 directed. For this purpose, a compressed air source or a compressed air supply, comprising a pump 10 , a hose connection 15 at the connection 4 a distributor 3 is provided, and a valve 11 with the entrance 7 of the canal 18 connected. By means of the compressed air source is the channel 18 supplied with compressed air. The compressed air source generates a corresponding pressure level, for example a differential pressure of 1.0 or 1.2 bar or another differential pressure to the ambient air. This pressure level is at the outlet of the valve 11 , ie upstream of the entrance 7 and in this embodiment, also upstream of the manifold 3 arranged pressure sensor 12 , made available. Downstream of the pressure sensor 12 is at a connection 5 of the distributor 3 a hose connection 16 with the entrance 7 at a connection 6 connected. The sensor 12 can also be directly at the entrance or in the entrance 7 of the canal 18 be provided. 1 shows the apparatus structure very schematically. Typically, endoscopes have multiple channels that need to be rinsed and checked. For this the distributor has 3 then usually also several connections 5 and several valves 11 to supply the various channels with compressed air. It can then also several pressure sensors 12 be provided, preferably for each channel to be checked, a pressure sensor, either in the distributor 3 or immediately at the entrance of each channel 18 can be arranged in each case.

2 schematically shows a pressure curve in a positive step response 21 , A positive step response occurs when the feed pressure level 20 is set from, for example, a differential pressure of 0 to, for example, 1 bar, which is in the upper range of 2 is indicated in the step function shown there. The positive step response 21 On top of that you can see a transient area 24 before, after a certain time t in a static pressure 23 proceed. The amount of static pressure 23 depends largely on the flow resistance of the channel 18 from. For large channels, a smaller differential pressure, for example of 0.2 bar, and for smaller channels, a larger differential pressure, for example, 0.8 bar, a. At a set differential pressure of, for example, 1.25 bar as Zuführdruckniveau creates a differential pressure at smaller channels of 1 to 1.1 bar. For example, for a large channel 18 , in which usually has to be expected with a differential pressure of 0.2 bar at a Zuführdruckniveau of 1.25 bar, a larger differential pressure measured, after the transient region, ie at the prevailing static pressure 23 , this speaks that there is a contamination of the channel. At a smaller measured differential pressure, this indicates that either the duct or the port to the duct is leaking.

For more detailed information, the settling range can be 24 with regard to the amplitude of the oscillation, the frequency of the oscillation and the duration of the transient. By way of example, this information can be obtained at what point, ie at what distance from the compressed air source, there is an impurity or a leak.

Additionally or alternatively, also a negative step response 22 be analyzed for a shutdown of the feed pressure level. This is in 3 schematically a corresponding pressure curve at a negative step response 22 at the bottom of the 3 shown. In the upper area is shown that first of a state where a static pressure 23 has adjusted due to a corresponding Zuführdruckniveaus of, for example, 1.25 bar differential pressure. It then becomes the supply pressure level, for example by closing the valve 11 or switching off the pump 10 set in a step function to 0 bar differential pressure. In this case, it will get into the system, ie after the valve 11 Compressed air within a certain time to the output 8th , Because of this, the pressure on the sensor drops 12 according to the pressure curve of the negative step response 22 from. For example, by forming an integral over a predeterminable time in a range of, for example, t1 to t2 conclusions about the flow resistance can be made. Alternatively or additionally, the slope of this curve can be determined at a certain time or the second derivative can be formed after the time.

Particularly preferably, the method is applied so that at least two or more blasts of compressed air in the channel 18 be admitted. These blasts of compressed air, in addition to analyzing the permeability or leakage, may be used to remove foreign matter from the channel 18 blow. By analyzing the pressure profiles, it can also be determined whether contaminations or blockages could be eliminated. Then, a usual cleaning process can be carried out by means of rinsing with a cleaning liquid.

All mentioned features, including the drawings alone to be taken as well as individual features that are disclosed in combination with other features are considered alone and in combination as essential to the invention. Embodiments of the invention may be accomplished by individual features or a combination of several features.

LIST OF REFERENCE NUMBERS

1

cleaner

2

endoscope

3

distributor

4, 5, 6

connection

7

entrance

8th

output

10

pump

11

Valve

12

pressure sensor

15, 16

hose connection

18

channel

20

Zuführdruckniveau

21

positive step response

22

negative step response

23

static pressure

24

Einschwingbereich

t

Time

P

print

Claims (6)

Method for operating a cleaning machine ( 1 ) from a one channel ( 18 elongated instrument ( 2 ), in particular endoscope, wherein the channel ( 18 ) an entrance ( 7 ) and an output ( 8th ), wherein a compressed air connection ( 6 ) at the entrance ( 7 ) of the channel ( 18 ), comprising the following steps: - supplying compressed air to the inlet ( 7 ) of the channel ( 18 ), wherein a feed pressure level ( 20 ) of the compressed air by connecting or disconnecting a compressed air supply ( 10 . 11 . 15 ), - measuring the pressure in front of the entrance ( 7 ) or in the entrance ( 7 ) of the channel ( 18 ) over a first predeterminable time (t) and - determining a transmission parameter of the channel ( 18 ) and / or determining the tightness of the channel ( 18 ) or the compressed air connection ( 6 ) on the channel ( 18 ), characterized in that for determining the transmission parameter of the channel ( 18 ) and / or the tightness of the channel ( 18 ) or the compressed air connection ( 6 ) on the channel ( 18 ) a step response ( 21 . 22 ) on changing the supply pressure level ( 20 ) and the analysis includes determining a slope and / or forming a second derivative of the measured pressure (P) over time. Method for operating a cleaning machine ( 1 ) from a one channel ( 18 elongated instrument ( 2 ), in particular endoscope, wherein the channel ( 18 ) an entrance ( 7 ) and an output ( 8th ), wherein a compressed air connection ( 6 ) at the entrance ( 7 ) of the channel ( 18 ), comprising the following steps: - supplying compressed air to the inlet ( 7 ) of the channel ( 18 ), wherein a feed pressure level ( 20 ) of the compressed air by connecting or disconnecting a compressed air supply ( 10 . 11 . 15 ), - measuring the pressure in front of the entrance ( 7 ) or in the entrance ( 7 ) of the channel ( 18 ) over a first predeterminable time (t) and - determining a transmission parameter of the channel ( 18 ) and / or determining the tightness of the channel ( 18 ) or the compressed air connection ( 6 ) on the channel ( 18 ), characterized in that for determining the transmission parameter of the channel ( 18 ) and / or the tightness of the channel ( 18 ) or the compressed air connection ( 6 ) on the channel ( 18 ) a step response ( 21 . 22 ) on changing the supply pressure level ( 20 ) is measured and analyzed and the analysis determines a duration, amplitude and / or wavelength of a vibration ( 24 ) of the measured pressure (P). Method according to claim 1 or 2, characterized in that the changing of the feed pressure level ( 20 ) is stepped. Method according to one of claims 1 to 3, characterized in that the analysis is a comparison of a static pressure ( 23 ) with one for the channel ( 18 ) includes a predetermined first value. Method according to one of claims 1 to 4, characterized in that the analysis comprises the formation of an integral of the measured pressure (P) over a second predetermined time and a comparison with one for the channel ( 18 ) contains a prescribable second value. Method according to one of claims 1 to 5, characterized in that the method steps before rinsing the channel ( 18 ) with a liquid.

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