Blockage detection device and blockage detection program

Abstract

To provide a detection device and a blockage detection program capable of issuing a highly accurate alarm regarding blockage of a liquid delivery tube.SOLUTION: A blockage detection device comprises: a detection unit which detects blockage of a liquid delivery tube by detecting a diameter change of a detection object part of the liquid delivery tube; a temperature adjustment unit which adjusts a temperature of the detection object part of the liquid delivery tube to a set temperature; an alarm unit which executes an alarm when the detection unit detects the blockage while the temperature of the detection object part of the liquid delivery tube is the set temperature; and a preliminary alarm unit which executes a preliminary alarm when the detection unit detects the blockage while the temperature of the detection object part of the liquid delivery tube is not the set temperature.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an occlusion detection device and an occlusion detection program. [Background technology]

[0002] There is known an occlusion detection device that detects a change in the diameter of a liquid supply tube to detect occlusion of the liquid supply tube and issue an alarm (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-254159 [Patent Document 2] Patent No. 3130658 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to provide a detection device and an occlusion detection program that can issue a highly accurate alarm regarding occlusion in a liquid delivery tube. [Means for solving the problem]

[0005] One aspect of the present disclosure is as follows.

[0006] [1] a detection unit that detects a change in diameter of a detection target portion of the liquid supply tube to detect a blockage of the liquid supply tube; a temperature adjusting unit that adjusts the temperature of the detection target portion of the liquid supply tube to a set temperature; an alarm unit that issues an alarm when the detection unit detects the blockage while the temperature of the detection target portion of the liquid supply tube is the set temperature; and a preliminary alarm unit that issues a preliminary alarm when the detection unit detects the blockage while the temperature of the detection target portion of the liquid supply tube is not at the set temperature.

[0007] [2] The obstruction detection device described in [1] has a drive unit that performs liquid delivery through the liquid delivery tube.

[0008] [3] The obstruction detection device described in [2], wherein the drive unit performs intermittent driving to repeatedly start and stop the liquid delivery through the liquid delivery tube.

[0009] [4] The blockage detection device described in [3], wherein the temperature adjustment unit repeatedly starts and stops adjusting the temperature in synchronization with the intermittent driving of the drive unit.

[0010] [5] The occlusion detection device described in [3] or [4], wherein the detection unit repeatedly performs and stops the occlusion detection in synchronization with the intermittent driving of the drive unit.

[0011] [6] The obstruction detection device described in any one of [2] to [5], wherein the drive unit performs reverse drive to perform reverse fluid transfer or emergency stop when the alarm is issued, but does not perform this when the preliminary alarm is issued.

[0012] [7] The detection unit a diameter change detection unit that detects a change in diameter of the detection target portion; a temperature detection unit that determines whether the temperature of the detection target unit is the set temperature; The blockage detection device according to any one of [1] to [6], further comprising a blockage determination unit that, when the temperature detection unit determines that the temperature of the detected portion is the set temperature, detects blockage based on the diameter change detected by the diameter change detection unit and a first blockage determination criterion, and, when the temperature detection unit determines that the temperature of the detected portion is not the set temperature, detects blockage based on the diameter change detected by the diameter change detection unit and a second blockage determination criterion different from the first blockage determination criterion.

[0013] [8] A computer that controls a blockage detection device having a detection unit, a temperature adjustment unit, an alarm unit, and a backup alarm unit, a detection step of detecting a change in diameter of a detection target portion of the liquid supply tube by the detection unit, thereby detecting a blockage of the liquid supply tube; a temperature adjusting step of adjusting the temperature of the detection target part to a set temperature by the temperature adjusting unit; an alarm step of issuing an alarm by the alarm unit when the blockage is detected in the detection step while the temperature of the detection target portion is the set temperature; a pre-alarm step of issuing a pre-alarm by the pre-alarm unit when the temperature of the detection target portion is not the set temperature in the detection step;

[0014] [9] The blockage detection device has a drive unit, The occlusion detection program described in [8] causes the computer to execute a driving step in which the drive unit sends liquid through the liquid delivery tube.

[0015]

[10] The obstruction detection program according to [9], wherein the driving step involves the driving unit performing intermittent driving to repeatedly start and stop the liquid delivery through the liquid delivery tube.

[0016]

[11] The blockage detection program according to

[10] , wherein the temperature adjustment step is performed by the temperature adjustment unit repeatedly executing and stopping the temperature adjustment in synchronization with the intermittent driving of the driving step.

[0017]

[12] The occlusion detection program according to

[10] or

[11] , wherein the detection step is performed by the detection unit repeatedly executing and stopping the detection of the occlusion in synchronization with the intermittent driving of the driving step.

[0018]

[13] The blockage detection program according to any one of [9] to

[12] , wherein the driving step performs reverse driving to perform reverse fluid transfer or emergency stop by the driving unit when the alarm is activated, but does not perform the reverse driving or emergency stop when the preliminary alarm is activated.

[0019]

[14] The detecting step a diameter change detection step of detecting the diameter change of the detection target portion by the detection unit; a temperature determination step in which the detection unit determines whether the temperature of the detection target unit is the set temperature; a first blockage determination step of detecting blockage by the detection unit based on the diameter change detected in the diameter change detection step and a first blockage determination criterion when it is determined in the temperature determination step that the temperature of the detection target portion is the set temperature; An occlusion detection program according to any one of [8] to

[13] , which has a second occlusion determination step in which, when it is determined in the temperature determination step that the temperature of the detected part is not the set temperature, the detection part detects occlusion based on the diameter change detected in the diameter change detection step and a second occlusion determination criterion different from the first occlusion determination criterion. [Effects of the Invention]

[0020] According to the present disclosure, it is possible to provide a detection device and an occlusion detection program that can provide a highly accurate alarm regarding occlusion of a liquid delivery tube. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic diagram illustrating a non-occluded state of a liquid delivery device having an occlusion detection device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic diagram showing a state in which the liquid delivery device shown in FIG. 1 is blocked. [Figure 3] FIG. 2 is a block diagram showing the configuration of the blockage detection device shown in FIG. 1. [Figure 4] 2 is a flow chart showing the operation of the blockage detection device shown in FIG. 1. [Figure 5] 1. FIG. 4 is a timing diagram showing an example of the operation of the blockage detection device shown in FIG. 1 when an alarm is issued without a preliminary alarm. [Figure 6] 1. FIG. 4 is a timing diagram showing an example of the operation of the blockage detection device shown in FIG. 1 when a warning is issued after a preliminary warning. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0023] As shown in Figures 1 to 6, an occlusion detection device 1 according to one embodiment of the present disclosure includes a detection unit 3 that detects occlusion in the liquid supply tube 2 by detecting a change in the diameter of the detectable portion 2a of the liquid supply tube 2, a temperature adjustment unit 4 that adjusts the temperature of the detectable portion 2a of the liquid supply tube 2 to a set temperature, an alarm unit 5 that issues an alarm when the detection unit 3 detects occlusion when the temperature of the detectable portion 2a of the liquid supply tube 2 is at the set temperature, and a preliminary alarm unit 6 that issues a preliminary alarm when the detection unit 3 detects occlusion when the temperature of the detectable portion 2a of the liquid supply tube 2 is not at the set temperature.

[0024] When liquid is delivered through the liquid delivery tube 2, if a blockage occurs in the liquid delivery tube 2, the pressure inside the liquid delivery tube 2 increases downstream of the drive unit 7 that delivers the liquid and upstream of the blockage (e.g., the portion blocked by the clamp 8 in Figure 2 ). This diameter change causes the liquid delivery tube 2 to expand. Therefore, the blockage of the liquid delivery tube 2 can be detected by detecting this diameter change. The diameter change of the liquid delivery tube 2 depends not only on the pressure inside the liquid delivery tube 2 but also on the ambient temperature. Therefore, by adjusting the temperature of the detection target portion 2a, where the diameter change of the liquid delivery tube 2 is detected, to a preset temperature using the temperature adjustment unit 4, the influence of the ambient temperature can be suppressed, thereby improving the accuracy of blockage detection by the detection unit 3. However, it is usually difficult to pre-adjust the temperature of the detection target portion 2a so that it always remains at the preset temperature. For example, if liquid delivery is initiated immediately after the power of the blockage detection device 1 is turned on, it takes some time for the temperature to reach the preset temperature. Although blockage detection is necessary during the time from the start of liquid delivery until the set temperature is reached, the accuracy of blockage detection during this time is not high. Therefore, by issuing a preliminary warning that is different from the normal warning issued after the set temperature is reached, a highly accurate warning can be issued according to the accuracy of blockage detection.

[0025] In this embodiment, the clogging detection device 1 has a drive unit 7 that sends liquid through the liquid feed tube 2. The clogging detection device 1 also has a computer 9 that controls the clogging detection device 1. The preliminary alarm unit 6 is composed of the computer 9 and an alarm unit 10, such as a buzzer or monitor, that issues an alarm using sound or an image under the control of the computer 9. The alarm unit 5 is composed of the computer 9, the alarm unit 10, and the drive unit 7. The drive unit 7 has a pressing unit 7a that sends liquid by pressing the liquid feed tube 2 under the control of the computer 9. The temperature adjustment unit 4 is composed of the computer 9, a temperature detection unit 11, such as a thermometer, that detects the temperature of the detection target portion 2a under the control of the computer 9, and a temperature adjuster 4a that adjusts the temperature of the detection target portion 2a to a set temperature under the control of the computer 9. The temperature adjuster 4a may be, for example, a heating / cooling device such as a Peltier element that can heat and cool, a heater that can heat, or a cooler that can cool.

[0026] The drive unit 7 delivers fluid to the human body through the fluid delivery tube 2. That is, in this embodiment, the medical fluid delivery device 13 is configured as a medical pump by the occlusion detection device 1, the fluid delivery tube 2, the liquid container 12, and the clamp 8. The medical fluid delivery device 13 is configured as an infusion device capable of infusing fluid through the fluid delivery tube 2 for PCA (Patient Controlled Analgesia), etc., but is not limited to this. The occlusion detection device 1 as a medical pump is not limited to an infusion pump in which the drive unit 7 has a pressing unit 7a, and may be configured as, for example, a syringe pump in which the drive unit 7 presses the plunger of a syringe that supplies fluid to the fluid delivery tube 2. The occlusion detection device 1 of this embodiment is particularly suitable for configuration as a portable medical pump that requires low power consumption.

[0027] As shown in Figures 5 and 6, the drive unit 7 performs intermittent drive, repeatedly starting and stopping the delivery of liquid through the liquid delivery tube 2. With the above configuration, good low-flow rate liquid delivery can be achieved through intermittent drive. Note that Figure 5 shows an example of a case where an alarm is issued without a preliminary alarm, and Figure 6 shows an example of a case where an alarm is issued after a preliminary alarm. In Figures 5 and 6, the upper solid line indicates the time when the drive unit 7 is delivering liquid, the middle solid line indicates the time when the drive unit 7 is stopping the delivery of liquid, and the lower solid line indicates the time when the drive unit 7 is driving in the reverse direction. Also, in Figures 5 and 6, the time when the temperature adjustment unit 4 is adjusting the temperature is indicated by the solid line in the upper row, the time when the temperature adjustment unit 4 has stopped adjusting the temperature is indicated by the solid line in the lower row, the time when the detection unit 3 is detecting blockage is indicated by the solid line in the upper row, the time when the detection unit 3 has stopped detecting blockage is indicated by the solid line in the lower row, the time when the preliminary alarm unit 6 is issuing a preliminary alarm is indicated by the solid line in the upper row, the time when the preliminary alarm unit 6 is not issuing a preliminary alarm is indicated by the solid line in the lower row, the time when the alarm unit 5 is issuing an alarm is indicated by the solid line in the upper row, and the time when the alarm unit 5 is not issuing an alarm is indicated by the solid line in the lower row.

[0028] The temperature adjustment unit 4 repeatedly starts and stops adjusting the temperature in synchronization with the intermittent drive of the drive unit 7. With the above configuration, the power consumption by the temperature adjustment unit 4 can be reduced by intermittent temperature adjustment synchronized with the intermittent drive. As a result, the temperature adjustment unit 4a can be made smaller, and therefore the blockage detection device 1 can be made smaller. In particular, if the temperature adjustment unit 4a is made up of a Peltier element, a large heat dissipation structure is not required.

[0029] The detector 3 repeatedly starts and stops detecting blockage in synchronization with the intermittent driving of the driver 7. According to the above configuration, the power consumption of the detector 3 can be reduced by intermittently detecting blockage in synchronization with the intermittent driving.

[0030] The driving unit 7 alternates between a running period during which the liquid is delivered and a stopping period during which the liquid is stopped, and the detection unit 3 alternates between a running period during which the blockage detection is performed and a stopping period during which the blockage detection is stopped, so that at least at a predetermined timing, the running period of the driving unit 7 falls within the running period of the detection unit 3. With the above configuration, blockages that occur during the running period of the driving unit 7 can be quickly detected.

[0031] The temperature adjustment unit 4 alternates between an execution period during which temperature adjustment is performed and an interruption period during which temperature adjustment is stopped, and at least at a predetermined timing, the execution period of the detection unit 3 falls within the execution period of the temperature adjustment unit 4. With the above configuration, it is possible to improve the accuracy of blockage detection while reducing the power consumption of the temperature adjustment unit 4.

[0032] The drive unit 7 performs reverse drive to send fluid in the reverse direction or an emergency stop when an alarm is issued, but does not perform this when a preliminary alarm is issued. With the above configuration, the pressure inside the fluid delivery tube 2 that has risen due to a blockage can be alleviated by reverse drive in response to an alarm, or a further increase can be prevented by an emergency stop, while when a preliminary alarm is issued, unnecessary reverse drive or emergency stop that would interfere with treatment can be prevented.

[0033] The detection unit 3 includes a diameter change detection unit 3a that detects a change in the diameter of the detection target portion 2a, a temperature detection unit 3b that determines whether the temperature of the detection target portion 2a is at a set temperature, and a blockage determination unit 3c that detects a blockage based on the diameter change detected by the diameter change detection unit 3a and a first blockage determination criterion when the temperature detection unit 3b determines that the temperature of the detection target portion 2a is at the set temperature, and a blockage determination unit 3c that detects a blockage based on the diameter change detected by the diameter change detection unit 3a and a second blockage determination criterion different from the first blockage determination criterion when the temperature detection unit 3b determines that the temperature of the detection target portion 2a is not at the set temperature. By changing the criteria for detecting a blockage, i.e., for determining that a blockage has occurred, depending on whether the temperature of the detection target portion 2a is at the set temperature or not, relatively accurate blockage detection is possible. However, because the accuracy of blockage detection is lower when the temperature of the detection target portion 2a is not at the set temperature than when the temperature of the detection target portion 2a is at the set temperature, issuing a preliminary warning rather than an alarm allows for more appropriate notification. The set temperature may be a predetermined value (e.g., 20°C) as shown in Figures 5 and 6, or may be a range of values having predetermined upper and lower limits (e.g., 15°C to 25°C, preferably 17°C to 23°C).

[0034] The detection unit 3 is composed of a temperature detection unit 3b, a diameter change detection unit 3a, and an obstruction determination unit 3c. The temperature detection unit 3b is composed of a temperature detection unit 11 and a temperature determination unit 3b1. The diameter change detection unit 3a is composed of a sensor (for example, a contact displacement sensor that uses magnetism or the like to detect the amount of displacement of a member that is pushed and displaced by the liquid supply tube 2 in conjunction with a change in the diameter of the liquid supply tube 2) or a camera, and detects a change in the diameter of the detection target 2a under the control of the computer 9. The obstruction determination unit 3c is composed of the computer 9. The temperature determination unit 3b1 is composed of the computer 9, and determines whether the temperature of the detection target 2a is at a set temperature based on the temperature detected by the temperature detection unit 11.

[0035] The occlusion detection unit calculates a calculated pressure value, which is a calculated value of the pressure of the detection target portion 2a, based on the detected value of the diameter change of the detection target portion 2a, and detects occlusion by comparing the calculated pressure value with the threshold value, which is the pressure value of the detection target portion 2a actually measured during occlusion. In this case, as shown in Figures 5 to 6, the detection of occlusion based on the diameter change detected by the diameter change detection unit 3a and the first occlusion determination criterion may be performed by comparing the calculated pressure value with the first threshold value (the upper dashed line in Figures 5 to 6), and the detection of occlusion based on the diameter change detected by the diameter change detection unit 3a and the second occlusion determination criterion may be performed by comparing the calculated pressure value with a second threshold value (the lower dashed line in Figures 5 to 6) that is different from the first threshold value. Alternatively, the detection of blockage based on the diameter change detected by the diameter change detection unit 3a and the first blockage determination criterion may be performed by comparing the first pressure calculation value with a threshold value, and the detection of blockage based on the diameter change detected by the diameter change detection unit 3a and the second blockage determination criterion may be performed by comparing the second pressure calculation value obtained by a calculation algorithm different from the calculation algorithm for the first pressure calculation value with the threshold value.

[0036] As shown in Figure 4, in this embodiment, the blockage detection program causes a computer 9 that controls an blockage detection device 1 having a detection unit 3, a temperature adjustment unit 4, an alarm unit 5, and a preliminary alarm unit 6 to execute the following steps: a detection step S1 in which the detection unit 3 detects a blockage in the liquid supply tube 2 by detecting a change in the diameter of the detectable portion 2a of the liquid supply tube 2; a temperature adjustment step S2 in which the temperature adjustment unit 4 adjusts the temperature of the detectable portion 2a to a set temperature; an alarm step S3 in which the alarm unit 5 issues an alarm if a blockage is detected in the detection step S1 when the temperature of the detectable portion 2a is at the set temperature; and a preliminary alarm step S4 in which the preliminary alarm unit 6 issues a preliminary alarm if a blockage is detected in the detection step S1 when the temperature of the detectable portion 2a is not at the set temperature.

[0037] The clogging detection device 1 has a drive unit 7, and the clogging detection program causes the computer 9 to execute a drive step S5 in which the drive unit 7 sends liquid through the liquid sending tube 2.

[0038] As shown in FIGS. 5 and 6, in the driving step S5, the driving unit 7 performs intermittent driving in which the liquid delivery through the liquid delivery tube 2 is repeatedly started and stopped.

[0039] In the temperature adjustment step S2, the temperature adjustment unit 4 repeatedly starts and stops adjusting the temperature in synchronization with the intermittent driving in the driving step S5.

[0040] In the detection step S1, the detection unit 3 repeatedly starts and stops detecting blockage in synchronization with the intermittent driving in the driving step S5.

[0041] In the driving step S5, the driving unit 7 performs reverse driving (see FIGS. 5 and 6) for sending the liquid in the reverse direction or performs an emergency stop when an alarm is issued, but does not perform the emergency stop when a preliminary alarm is issued.

[0042] The detection step S1 includes a diameter change detection step S1a in which the detection unit 3 detects a diameter change of the detection target portion 2a, a temperature determination step S1b in which the detection unit 3 determines whether the temperature of the detection target portion 2a is at a set temperature, a first blockage determination step S1c in which, when it is determined in the temperature determination step S1b that the temperature of the detection target portion 2a is at the set temperature, the detection unit 3 detects blockage based on the diameter change detected in the diameter change detection step S1a and a first blockage determination criterion, and a second blockage determination step S1d in which, when it is determined in the temperature determination step S1b that the temperature of the detection target portion 2a is not at the set temperature, the detection unit 3 detects blockage based on the diameter change detected in the diameter change detection step S1a and a second blockage determination criterion different from the first blockage determination criterion.

[0043] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and the above-described embodiments can be modified in various ways without departing from the gist of the present disclosure.

[0044] For example, the temperature adjustment step S2 may be configured to be executed before the start of the driving step S5. [Explanation of symbols]

[0045] 1. Blockage detection device 2. Liquid transfer tube 2a Detected part 3. Detection unit 3a Diameter change detector 3b Temperature detection part 3b1 Temperature judgment section 3c Occlusion determination section 4 Temperature control section 4a temperature controller 5 Alarm section 6. Preliminary Alarm Section 7 Drive unit 7a Pressing part 8. Klemme 9. Computer 10. Information Department 11 Temperature detection unit 12 Liquid containers 13 Medical fluid delivery device S1 Detection step S1a Diameter change detection step S1b Temperature determination step S1c First occlusion determination step S1d Second blockage determination step S2 Temperature adjustment step S3 Alarm step S4 Pre-alarm step S5 Drive Step

Claims

1. a detection unit that detects a change in diameter of a detection target portion of the liquid supply tube to detect a blockage of the liquid supply tube; a temperature adjusting unit that adjusts the temperature of the detection target portion of the liquid supply tube to a set temperature; an alarm unit that issues an alarm when the detection unit detects the blockage while the temperature of the detection target portion of the liquid supply tube is the set temperature; and a preliminary alarm unit that issues a preliminary alarm when the detection unit detects the blockage while the temperature of the detection target portion of the liquid supply tube is not at the set temperature.

2. The obstruction detection device according to claim 1 , further comprising a drive unit for driving the liquid through the liquid delivery tube.

3. The obstruction detection device according to claim 2 , wherein the drive unit performs intermittent driving to repeatedly start and stop the liquid delivery through the liquid delivery tube.

4. The obstruction detection device according to claim 3 , wherein the temperature adjustment unit repeatedly starts and stops adjusting the temperature in synchronization with the intermittent driving of the drive unit.

5. The obstruction detection device according to claim 3 , wherein the detector repeats execution and stopping of the obstruction detection in synchronization with the intermittent driving of the drive unit.

6. The obstruction detection device according to claim 2 , wherein the drive unit performs reverse drive for reversely feeding fluid or emergency stop when the alarm is issued, but does not perform the reverse drive when the preliminary alarm is issued.

7. The detection unit a diameter change detection unit that detects a change in diameter of the detection target portion; a temperature detection unit that determines whether the temperature of the detection target unit is the set temperature; 2. The clogging detection device according to claim 1, further comprising: a clogging determination unit that, when the temperature detection unit determines that the temperature of the detection target portion is the set temperature, detects clogging based on the diameter change detected by the diameter change detection unit and a first clogging determination criterion; and, when the temperature detection unit determines that the temperature of the detection target portion is not the set temperature, detects clogging based on the diameter change detected by the diameter change detection unit and a second clogging determination criterion different from the first clogging determination criterion.

8. A computer that controls a blockage detection device having a detection unit, a temperature adjustment unit, an alarm unit, and a backup alarm unit, a detection step of detecting a change in diameter of a detection target portion of the liquid supply tube by the detection unit, thereby detecting a blockage of the liquid supply tube; a temperature adjusting step of adjusting the temperature of the detection target part to a set temperature by the temperature adjusting unit; an alarm step of issuing an alarm by the alarm unit when the blockage is detected in the detection step while the temperature of the detection target portion is the set temperature; a pre-alarm step of issuing a pre-alarm by the pre-alarm unit when the temperature of the detection target portion is not the set temperature in the detection step;

9. The blockage detection device has a drive unit, The occlusion detection program according to claim 8 , wherein the occlusion detection program causes the computer to execute a driving step of causing the drive unit to feed liquid through the liquid feed tube.

10. The occlusion detection program according to claim 9 , wherein the driving step performs intermittent driving by the drive unit to repeatedly start and stop the liquid delivery through the liquid delivery tube.

11. The blockage detection program according to claim 10 , wherein the temperature adjusting step repeats execution and stop of the temperature adjustment by the temperature adjusting unit in synchronization with the intermittent driving of the driving step.

12. The occlusion detection program according to claim 10 , wherein the detection step causes the detection unit to repeatedly start and stop detecting the occlusion in synchronization with the intermittent driving of the driving step.

13. The obstruction detection program according to claim 9, wherein the driving step performs reverse driving or emergency stop by the driving unit to perform reverse fluid transfer when the alarm is issued, but does not perform the reverse driving or emergency stop when the preliminary alarm is issued.

14. The detecting step a diameter change detection step of detecting the diameter change of the detection target portion by the detection unit; a temperature determination step in which the detection unit determines whether the temperature of the detection target unit is the set temperature; a first blockage determination step of detecting blockage by the detection unit based on the diameter change detected in the diameter change detection step and a first blockage determination criterion when it is determined in the temperature determination step that the temperature of the detection target portion is the set temperature; 9. The blockage detection program according to claim 8, further comprising a second blockage determination step in which, when it is determined in the temperature determination step that the temperature of the detected portion is not the set temperature, the detection portion detects blockage based on the diameter change detected in the diameter change detection step and a second blockage determination criterion different from the first blockage determination criterion.

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