Patent Description:
For example, an occurrence of a crack (for example, due to aging, or the like) in an endoscope device (scope) can cause a water leak or an air leak during use (procedure), leading to the possibility of entrance of bacteria through the leak (crack) and its adhesion to the inside of the endoscope device. Therefore, the endoscope device must ensure airtightness.

In order to confirm whether the airtightness of the endoscope device is ensured, an inspection using a leak tester is typically performed before the procedure. With the leak tester connected to an air supply port (test air supply port) of an endoscope device, air is supplied to set the pressure inside the endoscope device to a predetermined value, and the internal pressure is monitored using a pressure sensor, thereby inspecting whether an air leak (that is, water leak) has occurred. Air leak inspection involves two types of inspection states: a dry test and a wet test. The dry test is an inspection performed in the atmosphere, and the wet test is an inspection performed in the water.

<CIT> discloses a leak detector for lumened instruments such as endoscopes of the watertight type. <CIT> discloses a leak testing device for use with an endoscope having a leak test port. <CIT> discloses a leak testing device to perform leak test accurately on an existing endoscope by adding a temperature sensor to the endoscope without making the endoscope larger and more complicated. <CIT> discloses a water leakage detector for endoscopes dispensing with an exhaust valve.

In a case where a dry test is performed, the endoscope device and the leak tester are in the same environment (including all of temperature, pressure, and humidity). This enables acquisition of an appropriate inspection result. In contrast, in a case where a wet test is performed, extremely low water temperature would decrease the pressure inside the endoscope device in some cases even though no air leak has occurred in the endoscope device. The internal pressure can drop by a few kPa just because of low water temperature. This might lead to an occurrence of a phenomenon in which the internal pressure of the endoscope device would not rise at all even with attempts to raise the internal pressure. Such a phenomenon can easily occur even in hospitals, and it is necessary to appropriately detect the presence or absence of an air leak even when a wet test in low-temperature water has to be performed.

The present disclosure has been made in view of such a situation and aims to provide a method for appropriately performing a wet test even with low water temperatures (that would not make a judgment of an air leak (error) just because of low water temperature).

In order to solve the above problems, the present embodiment provides a leak tester for inspecting the presence or absence of an air leak in an endoscope device,
the leak tester including:.

Further features related to the present disclosure will become apparent from the description of the present specification and the accompanying drawings. The present disclosure is achieved and implemented by elements and combinations of various elements and by modes of the following detailed description and the appended claims.

It is to be understood that the description in this specification is merely exemplary and is not intended to limit the scope of the claims or the application in any way.

According to the method of the present disclosure, a wet test can be appropriately performed even in low water temperature. That is, it is possible to implement a leak tester that would not make a judgment of an air leak (error) just because of low water temperature low at the time of the wet test.

In the following, an endoscope system will be described as an exemplary embodiment of the present disclosure.

<FIG> is a view illustrating a use mode of a leak tester (leak inspection device) according to the present embodiment, illustrating a state where the leak tester is connected to an endoscope device.

In <FIG>, reference numeral <NUM> denotes an endoscope device, which includes a bending section 11a to be bent by remote control provided near a distal end of the flexible insertion portion <NUM>, and which includes a connector unit <NUM> to be connected to a video processor (not illustrated), provided at a distal end of a joint flexible tube <NUM> extending rearward from an operation unit <NUM> joined to a proximal end of the flexible insertion portion <NUM>.

The endoscope device <NUM> configured as described above is entirely connected internally in a continuous manner, and is completely airtightly shut from the outside by a partition so as to suppress entry of water or air from the outside to the inside of the endoscope device <NUM>. The connector unit <NUM> includes a ventilation cap <NUM> for communication between the inside and the outside of the endoscope device <NUM>.

The ventilation cap <NUM> can be implemented by a known product. Inside the ventilation cap <NUM>, a movable plug <NUM> that closes between the outside and the inside is disposed to be biased from inside to outside by a coil spring <NUM>. Pressing the movable plug <NUM> to be retracted inward against the biasing force of the coil spring <NUM> would allow communication between the inside and the outside of the endoscope device <NUM>.

In the leak tester (leak inspection device) <NUM>, connecting a connection cap <NUM> attached to a distal end of a communication tube <NUM> extending from the leak tester <NUM> to the ventilation cap <NUM> would cause the movable plug <NUM> to be retracted inward so as to allow the communication tube <NUM> to communicate with the inside of the endoscope device <NUM>. Moreover, removing the connection cap <NUM> from the ventilation cap <NUM> in the leak tester <NUM> will close the ventilation cap <NUM> again. Thereafter, air is supplied into the endoscope device <NUM> by an air pump <NUM> provided inside the leak tester <NUM>, and the internal pressure change over time is monitored while increasing the internal pressure, thereby detecting whether an air leak due to a crack has occurred in the endoscope device <NUM>.

<FIG> is a diagram illustrating an internal configuration example of the leak tester <NUM> according to the present embodiment. In <FIG>, a solid line indicates a control signal line, and a dotted line indicates an air passage line.

The leak tester <NUM> includes a control unit <NUM>, an input unit <NUM>, an output unit <NUM>, an air pump <NUM>, a pressure sensor <NUM>, a solenoid valve <NUM>, and an air plug <NUM>.

The control unit <NUM> includes a processor such as a microprocessor or central processing unit (CPU), for example, and controls overall operation of the leak tester <NUM>, including control of a power supply circuit (not illustrated) and the air pump <NUM>, reading of output of the pressure sensor <NUM>, and display control.

The input unit <NUM> includes a push switch, for example, and is used by an operator to input leak test type information (dry test and wet test) and input an instruction to start the leak test. An instruction signal input by the input unit <NUM> is provided to the control unit <NUM>. The control unit <NUM> controls operation of the air pump <NUM>, the pressure sensor <NUM>, or the like, in response to the instruction signal.

The output unit <NUM> includes an LCD, an LED, and a buzzer, for example, and performs operation such as displaying a pressure target value, a current pressure value, elapsed time, and errors on the LCD, lighting or flashing a blue or red LED at leak discrimination or error occurrence, or sounding a buzzer at the time of operation switching, measurement completion (discrimination), error occurrence, or the like.

The air pump <NUM> has a function of supplying air into the endoscope device <NUM> to increase the pressure inside the endoscope device <NUM> (pressurizing function).

The pressure sensor <NUM> is implemented as a semiconductor piezo-type pressure sensor and has a function of detecting the pressure inside the endoscope device <NUM>.

The solenoid valve <NUM> has a function of maintaining the air pressure inside the endoscope device <NUM> or exhausting the air.

The air plug <NUM> is connected, at one attachment port, with an air pump <NUM>, a pressure sensor <NUM>, and a solenoid valve <NUM> and can be connected, at the other attachment port, with the communication tube <NUM>. Air is supplied from the air pump <NUM> to the inside of the endoscope device <NUM> via the air plug <NUM> and the communication tube <NUM> so as to be able to increase the pressure inside the endoscope device <NUM>.

<FIG> is a flowchart example illustrating operation of a leak tester according to the present embodiment.

An operator connects the communication tube <NUM> of the leak tester <NUM> to the endoscope device <NUM> and instructs the start of a dry test using the input unit <NUM> of the leak tester <NUM>. In response to this, an instruction signal (signal instructing the start of the dry test) is transmitted to control unit <NUM>. After receiving the instruction signal, the control unit <NUM> operates the air pump <NUM> to supply air into the endoscope device <NUM> through the air plug <NUM> and the communication tube <NUM> so as to increase the pressure inside the endoscope device <NUM> to a predetermined value (<NUM> kPa, for example). The control unit <NUM> monitors the internal pressure of the endoscope device <NUM> using the pressure sensor <NUM>, and stops the air supply from the air pump <NUM> when the pressure reaches <NUM> kPa.

The control unit <NUM> monitors a pressure value inside the endoscope device <NUM> detected by the pressure sensor <NUM> and determines whether the pressure has dropped by a predetermined value (for example, <NUM> kPa) within a predetermined time (for example, one minute). That is, it is judged whether the internal pressure of the endoscope device <NUM> has dropped from <NUM> kPa to <NUM> kPa or less within a predetermined time. In a case where a pressure drop of <NUM> kPa or more is detected (YES in step <NUM>), the process proceeds to step <NUM>. In a case where the pressure drop of <NUM> kPa or more is not detected (NO in step <NUM>), the process proceeds to step <NUM>.

The control unit <NUM> makes a judgment of dry test fail and displays the inspection result on the output unit (LCD, for example) <NUM> (step <NUM>).

The control unit <NUM> makes a judgment of dry test pass and displays an instruction for the operator to prepare for the wet test on the output unit (LCD, for example) <NUM>. Subsequently, the operator immerses the endoscope device <NUM> in the water stored in a water tank and inputs an instruction to start the wet test using the input unit <NUM>. After receiving a wet test start instruction signal, the control unit <NUM> operates the air pump <NUM> to supply air into the endoscope device <NUM> through the air plug <NUM> and the communication tube <NUM> again so as to increase the pressure inside the endoscope device <NUM> to a predetermined value (<NUM> kPa, for example). Note that when the internal pressure of the endoscope device <NUM> remains at <NUM> kPa at the end of the dry test, the repetitive air supply operation by the air pump <NUM> may be omitted.

The control unit <NUM> monitors a temporal change of the pressure value detected by the pressure sensor <NUM>.

Step <NUM> is a process of judging the possibility of the influence of the temperature of the water contained in the water tank. The process such as in step <NUM> will be performed in the present embodiment because the present inventors have found that the internal pressure of the endoscope device <NUM> can drop in low water temperature.

In step <NUM>, the control unit <NUM> continues to monitor the pressure value inside the endoscope device <NUM> detected by the pressure sensor <NUM> and determines whether the pressure has dropped by a predetermined value (<NUM> kPa, for example) immediately after the start of the wet test (within <NUM> seconds).

In a case where a pressure drop of <NUM> kPa or more is detected (YES in step <NUM>), the process proceeds to step <NUM>. That is, it is judged at this time that the pressure drop could have been detected due to the influence of the low water temperature, and further judgment will be made in step <NUM> whether the pressure has further dropped. In a case where the pressure drop of <NUM> kPa or more is not detected (NO in step <NUM>), the process proceeds to step <NUM>.

In step <NUM>, it is judged whether there is a pressure drop factor other than the water temperature. Note that the operator may check the presence or absence of an air leak visually by bending or folding the joint flexible tube <NUM> of the endoscope device <NUM> in the water tank during execution of the process of step <NUM>.

The control unit <NUM> judges whether the internal pressure of the endoscope device <NUM> has further dropped (drop by <NUM> kPa, for example) within a predetermined time (<NUM> seconds, for example). In a case where the pressure has further dropped (YES in step <NUM>), the process proceeds to step <NUM>. In a case where the pressure has not further dropped (NO in step <NUM>), the process proceeds to step <NUM>.

The control unit <NUM> judges whether the internal pressure of the endoscope device <NUM> has dropped to a normal pressure (for example, <NUM> kPa) or less after a predetermined time (one minute) has elapsed. That is, it is judged whether the internal pressure drop of the endoscope device <NUM> has reached <NUM> kPa within a predetermined time (one minute).

In a case where the internal pressure of the endoscope device <NUM> has not dropped to the normal pressure (for example, <NUM> kPa) or less (NO in step <NUM>), the process proceeds to step <NUM>. In a case where the internal pressure of the endoscope device <NUM> has dropped to the normal pressure (for example, <NUM> kPa) or less (YES in step <NUM>), the process proceeds to step <NUM>.

The control unit <NUM> makes a judgment of wet test pass.

The control unit <NUM> makes a judgment of wet test fail.

The control unit <NUM> displays an inspection result (pass or fail) on the output unit (for example, LCD) <NUM>. The types of inspection results include dry test fail (wet test would not be performed in this case), dry test pass/wet test pass, or dry test pass/wet test fail.

The functions of the present embodiment described above can also be implemented with software program codes. In this case, a storage medium recording the program code is provided to a system or a device, and then, a computer (or CPU, MPU, etc.) of the system or the device reads the program code stored in the storage medium. In this case, the program code read from the storage medium implements the functions of the above-described embodiments, and the program code and the storage medium storing the program code are configured to achieve the present disclosure. Examples of the storage medium applicable for supplying such a program code include a flexible disk, CD-ROM, DVD-ROM, hard disk, optical disk, magneto-optical disk, CD-R, magnetic tape, nonvolatile memory card, or ROM.

Moreover, it is allowable to have a configuration in which an operating system (OS) running on the computer performs part or all of actual processes on the basis of the instructions of the program code, and the functions of the above-described embodiments are implemented by the processes. Furthermore, it is also allowable to have a configuration in which the program code read from the storage medium is first written in the memory on the computer, and thereafter the computer CPU or the like performs part or all of the actual processes on the basis of the instruction of the program code, so as to implement the functions of the above-described embodiments by the processes.

Furthermore, it is also allowable to have a configuration in which the program code of the software for implementing the functions of the embodiment is distributed via a network, the program code is subsequently stored in a storage means such as a hard disk or memory of a system or device, or a storage medium such as a CD-RW or CD-R, and the computer (or CPU, MPU, etc.) of the system or device reads and executes the program code stored in the storage means or the storage medium at the time of use of the program code.

Finally, it should be understood that the processes and techniques described herein are not inherently related to any particular device, and can be implemented by any suitable combination of components. In addition, various types of general purpose devices can be used in accordance with the teaching described herein. It may prove useful to build a dedicated device to execute the steps in the method described herein. Various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiments. For example, some components may be deleted from all the components illustrated in the embodiment. Furthermore, components of different embodiments may be appropriately combined with each other. Although the present disclosure has been described with reference to specific examples, these are in all respects illustrative rather than restrictive. Those skilled in the art will recognize that there are numerous combinations of hardware, software, and firmware that are suitable to implement the present disclosure. For example, the software in description can be implemented in a wide range of programs or script languages such as assembler, C/C++, perl, Shell, PHP, Java (registered trademark).

Furthermore, in the above-described embodiment, control lines and information lines are considered to be necessary for explanation, and these are not necessarily illustrating control lines and information lines associated with the product. All the components may be connected to each other.

Claim 1:
A method for detecting an air leak in an endoscope device (<NUM>), comprising:
providing a leak tester (<NUM>) for inspecting presence or absence of an air leak in an endoscope device (<NUM>), comprising:
an air pump (<NUM>) for supplying air into the endoscope device (<NUM>);
a pressure sensor (<NUM>) that detects a pressure inside the endoscope device (<NUM>); and
a control unit (<NUM>) that controls operation of the air pump (<NUM>) and the pressure sensor (<NUM>) and judges the presence or absence of an air leak from the endoscope device (<NUM>),
executing, by the control unit:
operation of the air pump (<NUM>) to supply air into the endoscope device (<NUM>) to increase the pressure inside the endoscope device (<NUM>) to a predetermined value;
a first process of judging whether an internal pressure of the endoscope device (<NUM>) has dropped from said predetermined level, by a first pressure value within a first time span of within <NUM> seconds after start of a wet test, wherein at the start of the wet test an operator immerses the endoscope in water of a water tank;
a second process of judging whether the internal pressure has further dropped, by a second pressure value different from the first pressure value within a second time span different from the first time span in a case where the internal pressure has dropped, by the first pressure value in the first process;
a process of judging pass or fail in the wet test on the basis of a result of the second process; characterized in that the method further comprises
a third process of judging whether the internal pressure has further dropped, by a third pressure value different from the first pressure value within a third time span different from the first time span, in a case where the internal pressure has not dropped by the first pressure value in the first process, wherein the third process is conducted after one minute from the start of the wet test; and
a process of judging pass or fail in the wet test on the basis of a result of the third process.