Test apparatus, test method, heating device, and heating method

Abstract

SOLUTION: In a test device 10, a test method, a heating device 47 and a heating method, a tip part 30 of a sensor 12 is placed in an internal space 50 of a first heat insulation member 36. An outer peripheral surface of an intermediate part 52 of the sensor 12, other than the tip part 30, is covered with a second heat insulation member 42. A second heater 44 is provided on an outer peripheral surface of the second heat insulation member 42. A first heater 38 heats the tip part 30 of the sensor 12. Heat from the second heater 44 is transferred to the sensor 12 through a heat transmitting member 46 in the second heat insulation member 42.EFFECT: The temperature of parts of a sensor other than a tip part is less affected by an ambient environment. This makes it possible to conduct a test on the sensor in a simulated environment that is close to temperature gradient that occurs inside the sensor when it is in actual use.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a test apparatus, a test method, a heating apparatus, and a heating method.

Background Art

[0002] Patent Document 1 discloses a test apparatus for a sensor.

[0003] The sensor is attached to an exhaust pipe of an automobile. The sensor is attached to the exhaust pipe such that the tip portion is disposed inside the exhaust pipe. Exhaust gas (gas to be measured) discharged from the engine of the automobile flows through the exhaust pipe. The exhaust gas is a relatively high-temperature gas. The sensor detects a predetermined gas component contained in the exhaust gas and outputs a detection signal according to the detection result.

[0004] The test apparatus evaluates the behavior of the detection signal depending on the temperature by simulating the environment inside the exhaust pipe. Specifically, the tip portion of the sensor is disposed in a chamber that simulates the exhaust pipe. An inspection gas that simulates high-temperature exhaust gas is introduced into the chamber. The inspection gas is heated to a predetermined temperature by a burner. As the inspection gas flows through the chamber, the tip portion of the sensor is heated. The entire sensor is heated by heat conduction from the tip portion. The sensor detects the components of the inspection gas and outputs a detection signal according to the detection result.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] When the sensor is attached to the exhaust pipe, among the sensors, the part other than the tip is arranged outside the exhaust pipe. Among the sensors, the part other than the tip is heated by the heat transmitted from the engine or the like through the outside air.

[0007] On the other hand, in the test apparatus of Patent Document 1, among the sensors, the part other than the tip is arranged at a location far from a heat source such as a burner. Therefore, among the sensors, the part other than the tip is less likely to receive heat from the heat source. As a result, among the sensors, the part other than the tip is easily affected by the surrounding environment.

[0008] An object of the present invention is to solve the above-described problems.

Means for Solving the Problems

[0009] A first aspect of the present invention is a test apparatus for observing the behavior of a detection signal detected by a sensor extending along a predetermined direction according to temperature, the test apparatus having an internal space, a first heat insulating member in which a tip portion of the sensor is arranged in the internal space, a first heater provided in the internal space in a state of being separated from the sensor, a second heat insulating member that covers an outer peripheral surface of an intermediate portion other than the tip portion of the sensor and supports the sensor, a second heater provided on an outer peripheral surface of the second heat insulating member, and a heat transfer member provided in the second heat insulating member and configured to transfer heat of the second heater to the sensor.

[0010] A second aspect of the present invention is a test method for observing the behavior of a detection signal detected by a sensor extending along a predetermined direction according to temperature, in the test method, with a first heater provided in an internal space of a first heat insulating member, arranging a tip portion of the sensor in the internal space in a state of being separated from the first heater, covering an outer peripheral surface of an intermediate portion other than the tip portion of the sensor with a second heat insulating member to support the sensor, providing a second heater on an outer peripheral surface of the second heat insulating member, heating the tip portion of the sensor with the first heater, and transferring heat of the second heater to the sensor through a heat transfer member provided in the second heat insulating member.

[0011] A third aspect of the present invention is a heating device attachable to a sensor inspection apparatus including a chamber in which a tip of a sensor extending along a predetermined direction is disposed, wherein a portion of the sensor other than the tip is exposed to the outside from the chamber, and the heating device covers an outer peripheral surface of an intermediate portion of the sensor other than the tip and includes a heat insulating member that supports the sensor, a heater provided on the outer peripheral surface of the heat insulating member, and a heat transfer member provided in the heat insulating member and configured to transfer heat of the heater to the sensor.

[0012] A fourth aspect of the present invention is a heating method for heating a sensor extending along a predetermined direction. In the heating method, the tip is disposed in the chamber such that a portion of the sensor other than the tip is exposed to the outside from a chamber of a sensor inspection apparatus, an outer peripheral surface of an intermediate portion of the sensor other than the tip is covered with a heat insulating member to support the sensor, a heater is provided on the outer peripheral surface of the heat insulating member, and heat of the heater is transferred to the sensor through a heat transfer member provided in the heat insulating member.

Advantages of the Invention

[0013] According to the present invention, the temperature of a portion of the sensor other than the tip is less likely to be affected by the ambient environment. Thereby, it is possible to perform a test on the sensor in a state simulating an environment close to the temperature gradient generated inside the sensor during actual use.

[0014] Further, in the third and fourth aspects of the present invention, by externally attaching a heating device (heat insulating member, heater, and heat transfer member) to the sensor inspection apparatus, the above-described test can be performed on the sensor. That is, it is possible to perform the above-described test with a smaller equipment investment using existing equipment (such as a sensor inspection apparatus like a model gas apparatus).

Brief Description of the Drawings

[0015]

Figure 1

Best Mode for Carrying Out the Invention

[0016] FIG. 1 is a cross-sectional view of a test apparatus 10 according to the present embodiment. The test apparatus 10 is an apparatus for observing the behavior of the detection signal of the sensor 12 depending on the temperature.

[0017] The sensor 12 includes a sensor element 14, an outer cylinder 16, a fixing portion 18, a cover 20, and a sealing material 22.

[0018] The sensor element 14 has an elongated shape. The outer cylinder 16 covers the sensor element 14. The sensor element 14 is supported inside the outer cylinder 16 by a support member (not shown). The tip portion (the lower end portion in FIG. 1) of the sensor element 14 protrudes from the tip portion of the outer cylinder 16. The tip portion of the sensor element 14 is covered with the cover 20. The cover 20 is attached to the tip portion of the outer cylinder 16. By covering the tip portion of the sensor element 14 with the cover 20, an internal space (not shown) is formed around the tip portion of the sensor 12 inside the cover 20. The cover 20 is formed with a hole (not shown) that communicates the outside of the sensor 12 with the internal space of the cover 20.

[0019] A sealing material 22 such as a grommet is attached to the base end portion (the upper end portion in FIG. 1) of the outer cylinder 16. The inside of the outer cylinder 16 is sealed by the sealing material 22. A lead wire 24 passes through the sealing material 22. The lead wire 24 is connected to the sensor element 14. A fixing portion 18 is attached to the outer peripheral surface of the outer cylinder 16. The fixing portion 18 has a nut portion 26 and a bolt portion 28.

[0020] Among the sensor 12, the portion from the bolt portion 28 to the cover 20 is the tip portion 30 of the sensor 12. Among the sensor 12, the base end portion of the outer cylinder 16 is the base end portion 32 of the sensor 12.

[0021] The sensor 12 is attached to, for example, an exhaust pipe (not shown) of a vehicle. A screw hole is formed in the exhaust pipe. The sensor 12 is attached to the exhaust pipe by screwing the bolt portion 28 into the screw hole and bringing the nut portion 26 into contact with the outer peripheral surface of the exhaust pipe. As a result, the tip portion 30 of the sensor 12 is disposed inside the exhaust pipe. Among the sensor 12, portions other than the tip portion 30 are disposed outside the exhaust pipe.

[0022] During operation of the engine, relatively high-temperature exhaust gas is discharged from the engine to the exhaust pipe. The exhaust gas flows inside the exhaust pipe. The exhaust gas flows into the internal space of the sensor 12 through the holes. The tip portion 30 of the sensor 12 is heated by the heat of the exhaust gas. The sensor element 14 detects a predetermined gas component contained in the exhaust gas, which is the gas to be measured, and outputs a detection signal corresponding to the detection result. The detection signal is output from the sensor element 14 to the outside via the lead wire 24. Among the sensor 12, portions other than the tip portion 30 are heated by the heat transmitted through the outside air from the engine or the like.

[0023] The test device 10 observes the behavior of the detection signal depending on the temperature in a state simulating the environment of the sensor 12 attached to the exhaust pipe. The test device 10 includes a first chamber 34 (chamber), a first heat insulating member 36, a first heater 38, a second chamber 40, a second heat insulating member 42 (heat insulating member), a second heater 44 (heater), and a heat transfer member 46. In FIG. 1, the first chamber 34 and the second chamber 40 are schematically illustrated. Further, the second chamber 40, the second heat insulating member 42, the second heater 44, and the heat transfer member 46 constitute a heating device 47.

[0024] The first heat insulating member 36 and the first heater 38 are disposed inside the first chamber 34. The first heat insulating member 36 is a member having an internal space 50. In FIG. 1, a case where the first heat insulating member 36 is cylindrical is illustrated. Accordingly, the inside of the first heat insulating member 36 becomes the internal space 50. The internal space 50 simulates the inside of the exhaust pipe. The first heater 38 is disposed below the internal space 50. The first heater 38 is a coil heater.

[0025] The tip 30 of the sensor 12 is disposed in the internal space 50. Specifically, a screw hole (not shown) is formed in the upper wall 48 of the first chamber 34. The bolt portion 28 of the fixing portion 18 is screwed with the screw hole, and the nut portion 26 abuts against the upper wall 48 of the first chamber 34, whereby the sensor 12 is attached to the upper wall 48 of the first chamber 34. Thereby, the tip 30 of the sensor 12 is disposed inside the first chamber 34. In this case, in the internal space 50, the sensor 12 and the first heater 38 are disposed in a spaced-apart state from each other.

[0026] The second chamber 40 simulates the outside of the exhaust pipe. The second chamber 40 is disposed on the upper wall 48 of the first chamber 34. The second heater 44, the second heat insulating member 42, and the heat transfer member 46 are disposed inside the second chamber 40. Inside the second chamber 40, portions of the sensor 12 other than the tip 30 are disposed.

[0027] The second heat insulating member 42 covers the outer peripheral surface of the intermediate portion 52 between the tip 30 and the base end portion 32 of the sensor 12. Specifically, the second heat insulating member 42 covers portions of the outer cylinder 16 and the nut portion 26 other than the base end portion 32 of the sensor 12. The second heat insulating member 42 is a cylindrical member. The second heat insulating member 42 supports the sensor 12.

[0028] The second heater 44 is provided on the outer peripheral surface of the second heat insulating member 42. The second heater 44 is a cylindrical heater.

[0029] The heat transfer member 46 is provided inside the second heat insulating member 42. The heat transfer member 46 penetrates the second heat insulating member 42 and connects the second heater 44 and the outer cylinder 16. The heat transfer member 46 is a copper fixture.

[0030] Next, a method for testing the sensor 12 by the test apparatus 10 will be described.

[0031] First, place the first heat insulating member 36 and the first heater 38 inside the first chamber 34. In this case, arrange the first heat insulating member 36 so as to be substantially coaxial with the screw hole. Also, arrange the first heater 38 in the internal space 50 so as to be substantially coaxial with the screw hole.

[0032] Next, with the tip 30 of the sensor 12 inserted into the first chamber 34 through the screw hole, thread the bolt portion 28 of the fixing portion 18 with the screw hole. When the bolt portion 28 and the screw hole are threaded together and the nut portion 26 of the fixing portion 18 abuts against the upper wall 48 of the first chamber 34, the sensor 12 is attached to the upper wall 48 of the first chamber 34. As a result, the tip 30 of the sensor 12 is disposed in the internal space 50.

[0033] Next, arrange the second heat insulating member 42 on the upper wall 48 of the first chamber 34 so as to surround the portion (intermediate portion 52) of the sensor 12 that protrudes from the first chamber 34. Thereby, the heat transfer member 46 and the outer cylinder 16 are connected.

[0034] Next, arrange the second heater 44 outside the second heat insulating member 42. Thereby, the second heater 44 and the heat transfer member 46 are connected.

[0035] Next, arrange the second chamber 40 on the upper wall 48 of the first chamber 34. In this case, arrange the second chamber 40 on the upper wall 48 of the first chamber 34 so as to cover the sensor 12, the second heater 44, the second heat insulating member 42, and the heat transfer member 46. At this time, the lead wire 24 is drawn out from the second chamber 40 to the outside.

[0036] Next, supply the gas to be measured into the first chamber 34 from the outside. Next, drive the first heater 38 and the second heater 44. At this time, the heating temperature of the first heater 38 is set higher than the heating temperature of the second heater 44.

[0037] The first heater 38 heats the gas to be measured in the internal space 50. The heated gas to be measured is introduced from the hole in the cover 20 into the internal space of the cover 20. Thereby, the tip 30 of the sensor 12 is heated. The sensor element 14 detects a predetermined gas component contained in the gas to be measured and outputs a detection signal according to the detection result. The detection signal is output to the outside via the lead wire 24.

[0038] The heat of the second heater 44 is transmitted to the outer cylinder 16 via the heat transfer member 46. When heat is transmitted to the outer cylinder 16, the portion of the sensor 12 other than the tip 30 is heated. Specifically, the outer cylinder 16 and the sealing material 22 are heated by the heat transmitted to the outer cylinder 16. A second heat insulating member 42 is disposed between the second heater 44 and the outer cylinder 16. Thereby, the heat of the second heater 44 can be heat-transferred pinpoint to the connection portion between the heat transfer member 46 and the outer cylinder 16.

[0039] Note that the present invention is not limited to the above-described embodiments, and various configurations can be adopted without departing from the gist of the present invention.

[0040] As described above, the test apparatus 10 simulates the situation of an actual vehicle. Therefore, the heating temperature of each of the first heater 38 and the second heater 44 and the shape of the heat transfer member 46 can be appropriately changed according to the environment of the vehicle on which the sensor 12 is mounted.

[0041] In addition, in FIG. 1, the test for one sensor 12 has been described. The test apparatus 10 may perform tests on a plurality of sensors 12. In this case, the plurality of sensors 12 are fixed to the upper wall 48 of the first chamber 34 at a predetermined interval. The second chamber 40 is disposed on the upper wall 48 of the first chamber 34 so as to cover the plurality of sensors 12. In the test apparatus 10, the first heat insulating member 36, the first heater 38, the second heat insulating member 42, the second heater 44, and the heat transfer member 46 are disposed for each sensor 12. Thereby, it is possible to suppress variations in the temperature of the sensor 12 depending on the mounting location of the sensor 12 in the test apparatus 10.

[0042] Further, the heating device 47 may be detachable from the test device 10. By externally attaching the heating device 47 to a sensor inspection device such as an existing model gas device, it becomes possible to perform the above test on the sensor 12 using the existing equipment. That is, the heating device 47 can be used as an independent device. Note that the sensor inspection device may include, for example, a first chamber 34, a first heat insulating member 36, and a first heater 38.

[0043] Specifically, in a sensor inspection device with an externally attached heating device 47, by partially changing the above test method, the following test on the sensor 12 can be performed. In the following description, for the content common to the above test method, the description will be simplified or omitted.

[0044] First, the tip portion 30 of the sensor 12 is disposed in the first chamber 34 so that the portion other than the tip portion 30 of the sensor 12 is exposed to the outside from the first chamber 34 of the sensor inspection device. Next, a second heat insulating member 42 is disposed so as to surround the intermediate portion 52 protruding from the first chamber 34 of the sensor 12. Next, a second heater 44 is disposed outside the second heat insulating member 42. Next, a second chamber 40 is disposed on the upper wall 48 of the first chamber 34 so as to cover the sensor 12, the second heater 44, the second heat insulating member 42, and the heat transfer member 46.

[0045] Next, in the sensor inspection device, the tip portion 30 of the sensor 12 is heated. Also, by driving the second heater 44, the heat of the second heater 44 is transmitted to the outer cylinder 16 via the heat transfer member 46, and the portion other than the tip portion 30 of the sensor 12 is heated.

[0046] The invention that can be grasped from the above embodiments will be described below.

[0047] A first aspect of the present invention is a test apparatus (10) for observing the temperature behavior of a detection signal detected by a sensor (12) extending along a predetermined direction, the test apparatus having an internal space (50), a first heat insulating member (36) in which a tip portion (30) of the sensor is disposed in the internal space, a first heater (38) provided in the internal space in a spaced-apart state from the sensor, a second heat insulating member (42) that covers an outer peripheral surface of an intermediate portion (52) of the sensor other than the tip portion and supports the sensor, a second heater (44) provided on an outer peripheral surface of the second heat insulating member, and a heat transfer member (46) provided in the second heat insulating member and configured to transfer heat of the second heater to the sensor.

[0048] According to the present invention, each part of the sensor is less affected by the surrounding environment. Thereby, it is possible to perform a test on the sensor in a state simulating an environment close to the temperature gradient generated inside the sensor during actual use.

[0049] In the first aspect of the present invention, the test apparatus further includes a first chamber (34) that houses the tip portion of the sensor, the first heat insulating member, and the first heater.

[0050] Thereby, the tip portion of the sensor is less affected by the surrounding environment. Also, the temperature adjustment of the tip portion of the sensor becomes easy.

[0051] In the first aspect of the present invention, the test apparatus further includes a second chamber (40) that houses the intermediate portion of the sensor, the second heat insulating member, and the second heater.

[0052] Thereby, a portion of the sensor other than the tip portion is less affected by the surrounding environment. Also, the temperature adjustment of a portion of the sensor other than the tip portion becomes easy.

[0053] In the first aspect of the present invention, the first heater and the second heater are set to different heating temperatures.

[0054] As a result, the sensor can be tested in an environment close to actual use. That is, the sensor can be tested in a state where an environment similar to the temperature gradient generated inside the sensor during actual use is simulated.

[0055] In the first aspect of the present invention, the heating temperature of the first heater is higher than the heating temperature of the second heater.

[0056] As a result, the sensor can be tested in an even closer environment to actual use. That is, the sensor can be tested in a state where an environment even closer to the temperature gradient generated inside the sensor during actual use is simulated.

[0057] In the first aspect of the present invention, the heat transfer member is a jig made of copper.

[0058] As a result, heat can be efficiently transferred from the second heater to the sensor.

[0059] The second aspect of the present invention is a test method for observing the behavior of a detection signal detected by a sensor extending along a predetermined direction according to temperature, the test method including disposing a tip portion of the sensor in the internal space in a state separated from the first heater while the first heater is provided in an internal space of a first heat insulating member, covering an outer peripheral surface of an intermediate portion other than the tip portion of the sensor with a second heat insulating member to support the sensor, providing a second heater on an outer peripheral surface of the second heat insulating member, heating the tip portion of the sensor with the first heater, and transferring heat of the second heater to the sensor via a heat transfer member provided in the second heat insulating member.

[0060] According to the present invention, the temperature of the portion of the sensor other than the tip portion is less likely to be affected by the surrounding environment. As a result, the sensor can be tested in a state where an environment similar to the temperature gradient generated inside the sensor during actual use is simulated.

[0061] A third aspect of the present invention is a heating device (47) attachable to a sensor inspection device including a chamber (34) in which a tip portion of a sensor extending along a predetermined direction is disposed. Among the sensors, portions other than the tip portion are exposed to the outside from the chamber, and the heating device covers an outer peripheral surface of an intermediate portion other than the tip portion of the sensor, and includes a heat insulating member (42) that supports the sensor, a heater (44) provided on the outer peripheral surface of the heat insulating member, and a heat transfer member provided in the heat insulating member and configured to transfer heat of the heater to the sensor.

[0062] In the present invention, the above test can be performed on the sensor by externally attaching a heating device (heat insulating member, heater, and heat transfer member) to the sensor inspection device. That is, it becomes possible to perform the above test with a smaller equipment investment by using existing equipment (such as a sensor inspection device like a model gas device).

[0063] A fourth aspect of the present invention is a heating method for heating a sensor extending along a predetermined direction. In the heating method, the tip portion is disposed in the chamber such that a portion other than the tip portion of the sensor is exposed to the outside from the chamber of the sensor inspection device, an outer peripheral surface of an intermediate portion other than the tip portion of the sensor is covered with a heat insulating member to support the sensor, a heater is provided on the outer peripheral surface of the heat insulating member, and heat of the heater is transferred to the sensor via a heat transfer member provided in the heat insulating member.

[0064] Also in the present invention, the above test can be performed on the sensor by externally attaching a heating device (heat insulating member, heater, and heat transfer member) to the sensor inspection device. That is, it becomes possible to perform the above test with a smaller equipment investment by using existing equipment (such as a sensor inspection device like a model gas device).

Description of Reference Numerals

[0065] 10…Test device 12…Sensor 30…Tip portion 34…First chamber (chamber) 36…First heat insulating member 38…First heater 42…Second heat insulation member (heat insulation member) 44…Second heater (heater) 46…Heat transfer member 47…Heating device 50…Internal space 52…Intermediate part

Claims

1. A test apparatus for observing the behavior of a detection signal detected by a sensor extending along a predetermined direction according to temperature, a first heat insulating member having an internal space and having a tip portion of the sensor disposed in the internal space; a first heater provided in the internal space in a state of being separated from the sensor; a second heat insulating member that covers an outer peripheral surface of an intermediate portion other than the tip portion of the sensor and supports the sensor; a second heater provided on an outer peripheral surface of the second heat insulating member; a heat transfer member provided in the second heat insulating member and configured to transfer heat of the second heater to the sensor; A test apparatus comprising:

2. The test apparatus according to claim 1, further comprising: a first chamber that houses the tip portion of the sensor, the first heat insulating member, and the first heater.

3. The test apparatus according to claim 1 or 2, further comprising: a second chamber that houses the intermediate portion of the sensor, the second heat insulating member, and the second heater.

4. The test apparatus according to any one of claims 1 to 3, wherein the first heater and the second heater are set to different heating temperatures.

5. The test apparatus according to claim 4, wherein a heating temperature of the first heater is higher than a heating temperature of the second heater.

6. The test apparatus according to any one of claims 1 to 5, wherein the heat transfer member is a copper jig.

7. A test method for observing the behavior of a detection signal detected by a sensor extending along a predetermined direction according to temperature, the method comprising: placing a tip portion of the sensor in the internal space in a state of being separated from the first heater while the first heater is provided in the internal space of the first heat insulating member; covering an outer peripheral surface of an intermediate portion other than the tip portion of the sensor with a second heat insulating member to support the sensor; providing a second heater on an outer peripheral surface of the second heat insulating member; heating the tip portion of the sensor with the first heater; and transferring heat of the second heater to the sensor via a heat transfer member provided in the second heat insulating member.

8. A heating device attachable to a sensor inspection device including a chamber in which a tip portion of a sensor extending along a predetermined direction is disposed, wherein a portion of the sensor other than the tip portion is exposed to the outside from the chamber, and the heating device is Among the sensors, a heat insulating member that covers the outer peripheral surface of an intermediate portion other than the tip portion and supports the sensor; A heater provided on the outer peripheral surface of the heat insulating member; A heat transfer member provided in the heat insulating member and transferring the heat of the heater to the sensor; A heating device comprising the above.

9. A heating method for heating a sensor extending along a predetermined direction, comprising: Placing the tip portion of the sensor in the chamber such that a portion other than the tip portion of the sensor is exposed to the outside from the chamber of the sensor inspection device; Covering the outer peripheral surface of an intermediate portion other than the tip portion of the sensor with a heat insulating member to support the sensor; Providing a heater on the outer peripheral surface of the heat insulating member; A heating method of transferring the heat of the heater to the sensor via a heat transfer member provided in the heat insulating member.

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